# WILBERT

## Wildauer Bücher+E-Medien Recherche-Tool

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
• Springer  (2,353,329)
Collection
Keywords
Publisher
Language
Years
• 1
Online Resource
Wiesbaden : Springer Fachmedien Wiesbaden GmbH | Springer
Keywords: Immaterialgut ; Rechtsverletzung ; Wettbewerbsverstoß ; Verkehrssicherungspflicht ; Dritthaftung ; Beseitigungsanspruch ; Unterlassungsanspruch ; LA ; Gefahrengeneigte Geschäftsmodelle ; Intermediär ; Störerhaftung ; Teilnehmerhaftung ; Verkehrspflichten aus Ingerenz ; LA ; Hochschulschrift ; Immaterialgut ; Rechtsverletzung ; Wettbewerbsverstoß ; Verkehrssicherungspflicht ; Dritthaftung ; Beseitigungsanspruch ; Unterlassungsanspruch
Type of Medium: Online Resource
Pages: 1 Online-Ressource (XIII, 255 Seiten)
ISBN: 9783658251062
Series Statement: Juridicum - Schriften zum Unternehmens- und Wirtschaftsrecht
Language: German
Dissertation note: Dissertation Universität Konstanz 2018
Location Call Number Limitation Availability
Others were also interested in ...
• 2
Unknown
Springer
Publication Date: 2018-03-07
Description: Background Glenoid replacement in cases of severe glenoid retroversion (RV) or eccentric wear is challenging. The aim of this study was to evaluate different treatment methods under standardized conditions to assist surgeons in the decision-making process. Methods Three treatment options for severe glenoid RV (15°) were compared: (1) no RV correction; (2) complete RV correction; (3) no RV correction and implantation of a posterior augmented glenoid (PAG). A highly standardized implantation protocol using artificial glenoid bones (five per group) was chosen, and a physiologic shoulder movement was applied in a biomechanical setting. Micromotions (MM) between glenoid components and bone were quantified using an optical 3D measuring system. Results In the uncorrected retroversion group, three instances of subluxation of the prosthetic head occurred between 2000 and 4000 cycles. At 2000 cycles, significantly more MM were observed in the uncorrected RV group than in the corrected RV group ( p  〈 0.0001) or to the augmented group ( p  〈 0.0001). At 10|000 cycles, more MM were observed in the posterior augmented group than in the corrected RV group ( p  〈 0.0001). Conclusion If sufficient bone stock is available, retroversion correction should be favored. Posterior augmented glenoids seem to be a suitable treatment option if complete correction of the retroversion is not possible without compromising the glenoid vault. Without correction of the retroversion, high failure rates were observed.
Print ISSN: 0936-8051
Electronic ISSN: 1434-3916
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 3
Unknown
Springer
Publication Date: 2018-03-07
Description: Following the LAMOST Spectroscopic Survey and the Xuyi’s Photometric Survey of the Galactic Anti-center, we plan to carry out a time-domain survey of the Galactic Anti-center (TDS-GAC) to study variable stars by using the Nanshan 1-meter telescope. Before the beginning of TDS-GAC, a precursive sky survey (PSS) has been executed. The goal of the PSS is to optimize the observation strategy of TDS-GAC and to detect some strong transient events, as well as to find some short time-scale variable stars of different types. By observing a discontinuous sky area of $$15.03~\mbox{deg}^{2}$$ with the standard Johnson-Cousin-Bessel $$V$$ filter, 48 variable stars are found and the time series are analyzed. Based on the behaviors of the light curves, 28 eclipsing binary stars, 10 RR Lyraes, 3 periodic pulsating variables of other types have been classified. The rest 7 variables stay unclassified with deficient data. In addition, the observation strategy of TD-GAC is described, and the pipeline of data reduction is tested.
Print ISSN: 0004-640X
Electronic ISSN: 1572-946X
Topics: Physics
Location Call Number Limitation Availability
Others were also interested in ...
• 4
Unknown
Springer
In: Biologia
Publication Date: 2018-03-07
Description: Gene knockdown and gene-silencing pathways in eukaryotic organisms are associated with small RNAs 20 to 25 nucleotides in length, which include microRNAs (miRNAs) and small interfering RNAs (siRNAs). These small RNAs are recruited to repress gene expression upstream or downstream of the transcription pathway. RNA interference (RNAi) is a biological inhibitor of gene expression that results in the destruction of messenger RNAs (mRNAs), leading to the inhibition of protein production. Indeed, RNA silencing plays a key role in plant development in terms of the plant’s response to both biotic and abiotic stresses. Conversely, Viral Suppressors of RNA silencing (VSRs) are proteins that hamper antiviral RNAi activation in plants, lead to suppress plant RNA-silencing. These VSR proteins prevent the induction of the plant antiviral RNAi immune response. This review focuses on small RNAs in plants and their roles in the responses of plants to biotic and abiotic stresses.
Print ISSN: 0006-3088
Electronic ISSN: 1336-9563
Topics: Biology
Location Call Number Limitation Availability
Others were also interested in ...
• 5
Unknown
Springer
Publication Date: 2018-03-07
Description: Matthew Liao’s edited collection Moral Brains: The Neuroscience of Morality covers a wide range of issues in moral psychology. The collection should be of interest to philosophers, psychologist, and neuroscientists alike, particularly those interested in the relation between these disciplines. I give an overview of the content and major themes of the volume and draw some important lessons about the connection between moral neuroscience and normative ethics. In particular, I argue that moving beyond some of the dichotomies implicit in some of the debates advanced in the book makes the neuroscience of moral judgment much more useful in advancing normative ethics.
Print ISSN: 0169-3867
Electronic ISSN: 1572-8404
Topics: Biology , Philosophy
Location Call Number Limitation Availability
Others were also interested in ...
• 6
Unknown
Springer
Publication Date: 2018-03-07
Description: The factors affecting variation in the abundances of invasive mammal species have seldom been evaluated at large spatial scales. We used data collected in a large-scale biodiversity monitoring program to identify variables predicting abundances of common brushtail possums ( Trichosurus vulpecula ; ‘possum’), a marsupial folivore introduced to New Zealand in the 1800s. We sampled possum abundances, vegetation structure and composition, and abiotic variables at 395 spatially representative sites in natural forest on the North, South and Stewart islands. Records of possum control were obtained from management agencies. The large sample size enabled us to consider the relative importance of 27 variables for possum abundances. Twelve variables explained 80% of the contributions to the final boosted regression tree model. Control history had the largest contribution to the model, with sites subject to aerial 1080 poison baiting either once or more than once in the previous 7 years having possum abundances 64% and 74% lower, respectively, than sites without control. Possum abundances were also negatively related to humidity, stem density, tree cover density, slope, elevation and distance to pasture/crop. Abundances increased with increasing food plant species richness, Weinmannia racemosa (a preferred food tree) cover, and solar radiation. There was an interaction between longitude and control history. We conclude that invasive possum abundances in New Zealand’s natural forests are determined by multiple biotic and abiotic factors, sometimes in interaction. Recent control operations, however, have greatly reduced possum abundances. Increasing the spatial extent of aerial 1080 poison baiting will further reduce possum abundances in New Zealand forests.
Print ISSN: 1387-3547
Electronic ISSN: 1573-1464
Topics: Biology
Location Call Number Limitation Availability
Others were also interested in ...
• 7
Unknown
Springer
Publication Date: 2018-03-07
Description: The paper offers a partial vindication of Sterelny’s view on the role of error rates and reliability in his theory of decoupled representation based on modelling techniques borrowed from the biological literature on evolution in stochastic environments. In the case of a tight link between tracking states and behaviour, I argue that in its full generality Sterelny’s account instantiates the base-rate fallacy. With regard to non-tightly linked behaviour, I show that Sterelny’s account can be vindicated subject to an adequate evolutionary model and a suitable notion of reliability.
Print ISSN: 0169-3867
Electronic ISSN: 1572-8404
Topics: Biology , Philosophy
Location Call Number Limitation Availability
Others were also interested in ...
• 8
Unknown
Springer
Publication Date: 2018-03-06
Description: Background Periodontal disease (PD) and colorectal cancer (CRC) were associated with chronic inflammation. This retrospective cohort study examined the association between PD severity and CRC in a large-scale, population-based Chinese cohort. Methods A total of approximately 106,487 individuals with newly diagnosed PD and 106,487 age-matched and sex-matched patients without PD from 2000 to 2002 were identified from Taiwan’s National Health Insurance Research Database (NHIRD). Results The Kaplan–Meier analysis revealed that the cumulative incidence of CRC was significantly higher in patients with PD than in those without PD (log-rank test, P  〈 0.001). After adjustment for age, sex, and comorbidities, patients with PD were associated with a significantly higher risk of CRC compared with those without PD (adjusted HR = 1.64, 95% CI = 1.50–1.80). Further, the risk of CRC appeared to increase with increasing frequency of PD medical visits [adjusted HR (95% CI) was 1.78 (1.58–2.02) and 1.53 (1.35–1.74) for annual visits 〉 10 and 〈 4, respectively]. Conclusion Based on our study, PD severity was associated with an increase in the risk of CRC. Further mechanistic research is needed.
Print ISSN: 0179-1958
Electronic ISSN: 1432-1262
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 9
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Diverting ileostomies help prevent major complications related to anastomoses after colorectal resection but can cause metabolic derangement and hypovolemia, leading to readmission. This paper aims to determine whether angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) use increased the risk of readmission, or readmission specifically for dehydration after new ileostomy creation. Methods Retrospective analysis of patients undergoing diverting ileostomy at a tertiary-care hospital, 2009–2015. Primary outcome was 60-day readmission for dehydration; secondary outcomes included 60-day readmission for any cause, or for infection obstruction. Results Ninety-nine patients underwent diverting ileostomy creation, 59% with a primary diagnosis of colorectal cancer. The 60-day readmission rate was 36% ( n  = 36). Of readmitted patients, 39% ( n  = 14) were admitted for dehydration. Other readmission reasons were infection (33%) and obstruction (3%). The majority (64%, n  = 9) of patients readmitted for dehydration were taking either an ACEi or an ARB. Compared to patients not readmitted for dehydration, those who were readmitted for dehydration were more likely to be on an ACEi or an ARB (11/85, 13% vs. 9/14, 64%). After controlling for covariates, ACEi or ARB use was significantly associated with risk of readmission ( p  〈 0.0001, odds ratio = 13.56, 95% confidence interval 3.54–51.92,). No other diuretic agent was statistically associated with readmission for dehydration. Conclusions ACEi and ARB use is a significant risk factor for readmission for dehydration following diverting ileostomy creation. Consideration should be given to withholding these medications after ileostomy creation to reduce this risk.
Print ISSN: 0179-1958
Electronic ISSN: 1432-1262
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 10
Unknown
Springer
Publication Date: 2018-03-06
Description: Background An anastomotic leak is a fairly common and a potentially lethal complication in colorectal surgery. Objective methods to assess the viability and blood circulation of the anastomosis could help in preventing leaks. Intraoperative pulse oximetry is a cheap, easy to use, fast, and readily available method to assess tissue viability. Our aim was to study whether intraoperative pulse oximetry can predict the development of an anastomotic leak. Methods The study was a prospective single-arm study conducted between the years 2005 and 2011 in Helsinki University Hospital. Patient material consisted of 422 patients undergoing elective left-sided colorectal surgery. The patients were operated by one of the three surgeons. All of the operations were partial or total resections of the left side of the colon with a colorectal anastomosis. The intraoperative colonic oxygen saturation was measured with pulse oximetry from the colonic wall, and the values were analyzed with respect to post-operative complications. Results 2.3 times more operated anastomotic leaks occurred when the colonic StO 2 was ≤ 90% (11/129 vs 11/293). The mean colonic StO 2 was 91.1 in patients who developed an operated anastomotic leak and 93.0 in patients who did not. With logistic regression analysis, the risk of operated anastomotic leak was 4.2 times higher with StO 2 values ≤ 90%. Conclusions Low intraoperative colonic StO 2 values are associated with the occurrence of anastomotic leak. Despite its handicaps, the method seems to be useful in assessing anastomotic viability.
Print ISSN: 0179-1958
Electronic ISSN: 1432-1262
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 11
Unknown
Springer
Publication Date: 2018-03-06
Description: Background Although a few reports have suggested transanal drainage tube (TDT) can reduce the pressure in the anastomotic portion, it remains unclear whether TDT can prevent anastomotic leakage (AL). In addition, little is known about the relationship between AL and daily fecal volume through TDT. This study investigated the role of TDT for the prevention of AL following laparoscopic low anterior resection (LAR). Methods This is a retrospective analysis of a prospectively maintained database of 201 rectal cancer patients who underwent laparoscopic LAR. The relationship between AL and daily fecal volume through TDT was examined. Results AL occurred in 25 patients. Based on the TDT grouping, AL occurred in 10.7% (19/178) of the TDT group, whereas it occurred in 26.1% (6/23) of the non-TDT group ( P  = 0.046). In the 178 patients with TDT placement, the daily fecal volumes on postoperative days (PODs) 2–5 were significantly higher compared with those on POD 1 ( P  〈 0.05). The daily fecal volume was observed to be gradually increasing until POD 3 or 4 (median, 25 or 23 ml/day, respectively) and then significantly decreasing on POD 5 (10 ml/day) ( P  〈 0.05). The AL rate of the patients whose daily fecal volume exceeded 100 ml/day in two or more days was significantly higher than that of those in 0 or 1 day (26.9 vs. 7.9%; P  〈 0.01). Conclusions TDT could be efficient to prevent AL following laparoscopic LAR. Postoperative fecal volume may be a reliable predictor of AL.
Print ISSN: 0179-1958
Electronic ISSN: 1432-1262
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 12
Unknown
Springer
Publication Date: 2018-03-06
Description: Background In order to improve the surgical treatment of rectal cancer, robot-assisted laparoscopy has been introduced. The robot has gained widespread use; however, the scientific basis for treatment of rectal cancer is still unclear. The aim of this study was to investigate whether robot-assisted laparoscopic rectal resection cause less perioperative pain than standard laparoscopic resection measured by the numerical rating scale (NRS score) as well as morphine consumption. Methods Fifty-one patients were randomized to either laparoscopic or robot-assisted rectal resection at the Department of Surgery at Aarhus University Hospital in Denmark. The intra-operative analgetic consumption was recorded prospectively and registered in patient records. Likewise all postoperative medicine administration including analgesia was recorded prospectively at the hospital medical charts. All morphine analogues were converted into equivalent oral morphine by a converter. Postoperative pain where measured by numeric rating scale (NRS) every hour at the postoperative care unit and three times a day at the ward. Results Opioid consumption during operation was significantly lower during robotic-assisted surgery than during laparoscopic surgery ( p =0.0001). However, there were no differences in opioid consumption or NRS in the period of recovery. We found no differences in length of surgery between the two groups; however, ten patients from the laparoscopic group underwent conversion to open surgery compared to one from the robotic group ( p =0.005). No significant difference between groups with respect to complications where found. Conclusions In the present study, we found that patients who underwent rectal cancer resection by robotic technique needed less analgetics during surgery than patients operated laparoscopically. We did, however, not find any difference in postoperative pain score or morphine consumption postoperatively between the robotic and laparoscopic group.
Print ISSN: 0179-1958
Electronic ISSN: 1432-1262
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 13
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Surgery is one of the riskiest and most important medical acts that are performed today. The need to improve patient outcomes and surgeon training, and to reduce the costs of surgery, has motivated the equipment of operating rooms with sensors that record surgical interventions. The richness and complexity of the data that are collected call for new methods to support computer-assisted surgery. The aim of this paper is to support the monitoring of junior surgeons learning their surgical skill sets. Methods Our method is fully automatic and takes as input a series of surgical interventions each represented by a low-level recording of all activities performed by the surgeon during the intervention (e.g., cut the skin with a scalpel). Our method produces a curve describing the process of standardization of the behavior of junior surgeons. Given the fact that junior surgeons receive constant feedback from senior surgeons during surgery, these curves can be directly interpreted as learning curves. Results Our method is assessed using the behavior of a junior surgeon in anterior cervical discectomy and fusion surgery over his first three years after residency. They revealed the ability of the method to accurately represent the surgical skill evolution. We also showed that the learning curves can be computed by phases allowing a finer evaluation of the skill progression. Conclusion Preliminary results suggest that our approach constitutes a useful addition to surgical training monitoring.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 14
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose We propose a framework for automatic and accurate detection of steeply inserted needles in 2D ultrasound data using convolution neural networks. We demonstrate its application in needle trajectory estimation and tip localization. Methods Our approach consists of a unified network, comprising a fully convolutional network (FCN) and a fast region-based convolutional neural network (R-CNN). The FCN proposes candidate regions, which are then fed to a fast R-CNN for finer needle detection. We leverage a transfer learning paradigm, where the network weights are initialized by training with non-medical images, and fine-tuned with ex vivo ultrasound scans collected during insertion of a 17G epidural needle into freshly excised porcine and bovine tissue at depth settings up to 9 cm and $$40^{\circ }$$ – $$75^{\circ }$$ insertion angles. Needle detection results are used to accurately estimate needle trajectory from intensity invariant needle features and perform needle tip localization from an intensity search along the needle trajectory. Results Our needle detection model was trained and validated on 2500 ex vivo ultrasound scans. The detection system has a frame rate of 25 fps on a GPU and achieves 99.6% precision, 99.78% recall rate and an $${F}_{1}$$ score of 0.99. Validation for needle localization was performed on 400 scans collected using a different imaging platform, over a bovine/porcine lumbosacral spine phantom. Shaft localization error of $$0.82^{\circ }\pm 0.4^{\circ }$$ , tip localization error of $$0.23\pm 0.05$$ mm, and a total processing time of 0.58 s were achieved. Conclusion The proposed method is fully automatic and provides robust needle localization results in challenging scanning conditions. The accurate and robust results coupled with real-time detection and sub-second total processing make the proposed method promising in applications for needle detection and localization during challenging minimally invasive ultrasound-guided procedures.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 15
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose It is controversial whether patients fare better with conservative or surgical treatment in certain stages of acute diverticulitis (AD), in particular when phlegmonous inflammation or covered micro- or macro-perforation are present. The aim of this study was to determine long-term quality of life (QoL) for AD patients who received either surgery or conservative treatment in different stages. Methods We included patients treated for AD at the University Hospital Grosshadern, Munich, Germany, between January 1, 2000, and December 31, 2010. Patients were classified by the Hansen and Stock (HS) classification, the modified Hinchey classification, and the German classification of diverticular disease (CDD). Pre-therapeutic staging was based on multidetector computed tomography. Long-term QoL was assessed by the Cleveland Global Quality of Life (CGQL) questionnaire, the Short Form 36 (SF-36), and the Gastrointestinal Quality of Life Index (GIQLI). Data are mean ± SEM. Results Patients with phlegmonous AD (HS type 2a, Hinchey Ia and CDD 1b, respectively) had a better long-term QoL on the GIQLI when they were operated (78.5 ± 2.5 vs. 70.7 ± 2.1; p  〈 0.05). Patients with micro-abscess (CDD 2a) had a better long-term QoL on the GIQLI, CGQL, and the “Role Physical” scale of the SF-36 when they were not operated (GIQLI 86.9 ± 2.1 vs. 76.8 ± 1.0; p  = 0.10; CGQL 82.8 ± 5.1 vs. 65.3 ± 11.0; p  = 0.08; SF-36/Role Physical 100 ± 0.0 vs. 41.7 ± 13.9; p  〈 0.001). Patients with macro-abscess (CDD 2b) had a better long-term QoL when they were operated (GIQLI 89.3 ± 1.4 vs. 69.5 ± 4.5; p  〈 0.01; CGQL 80.3 ± 7.6 vs. 60.5 ± 5.8; p  〈 0.05; SF-36/Role Physical 95.8 ± 4.2 vs. 47.9 ± 13.6; p  〈 0.001). Conclusion Considering long-term QoL, phlegmonous AD (HS type 2a, Hinchey Ia and CDD 1b, respectively) should be treated conservatively. In patients with covered perforation, abscess size should guide the decision on whether to perform surgery later on or not. In the light of long-term quality of life, patients fare better after elective sigmoid colectomy when abscess size exceeds 1 cm.
Print ISSN: 0179-1958
Electronic ISSN: 1432-1262
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 16
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Interventions at the otobasis operate in the narrow region of the temporal bone where several highly sensitive organs define obstacles with minimal clearance for surgical instruments. Nonlinear trajectories for potential minimally invasive interventions can provide larger distances to risk structures and optimized orientations of surgical instruments, thus improving clinical outcomes when compared to existing linear approaches. In this paper, we present fast and accurate planning methods for such nonlinear access paths. Methods We define a specific motion planning problem in $$\mathrm{SE}(3)=\mathbb {R}^3\times \mathrm{SO(3)}$$  with notable constraints in computation time and goal pose that reflect the requirements of temporal bone surgery. We then present $$\kappa$$ -RRT-Connect: two suitable motion planners based on bidirectional Rapidly exploring Random Tree (RRT) to solve this problem efficiently. Results The benefits of $$\kappa$$ -RRT-Connect are demonstrated on real CT data of patients. Their general performance is shown on a large set of realistic synthetic anatomies. We also show that these new algorithms outperform state-of-the-art methods based on circular arcs or Bézier–Splines when applied to this specific problem. Conclusion With this work, we demonstrate that preoperative and intra-operative planning of nonlinear access paths is possible for minimally invasive surgeries at the otobasis.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 17
Unknown
Springer
Publication Date: 2018-03-06
Description: The author would like to include grant number of NSERC Discovery grant in the acknowledgement section of the original article.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 18
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Ultrasound acquisitions are typically affected by deformations due to the pressure applied onto the contact surface. While a certain amount of pressure is necessary to ensure good acoustic coupling and visibility of the anatomy under examination, the caused deformations hinder accurate localization and geometric analysis of anatomical structures. These complications have even greater impact in case of 3D ultrasound scans as they limit the correct reconstruction of acquired volumes. Methods In this work, we propose a method to estimate and correct the induced deformation based solely on the tracked ultrasound images and information about the applied force. This is achieved by modeling estimated displacement fields of individual image sequences using the measured force information. By representing the computed displacement fields using a graph-based approach, we are able to recover a deformation-less 3D volume. Results Validation is performed on 30 in vivo human datasets acquired using a robotic ultrasound framework. Compared to ground truth, the presented deformation correction shows errors of $$3.39 \, \pm \, 1.86\,\hbox {mm}$$ for an applied force of 5 N at a penetration depth of 55 mm. Conclusion The proposed technique allows for the correction of deformations induced by the transducer pressure in entire 3D ultrasound volumes. Our technique does not require biomechanical models, patient-specific assumptions or information about the tissue properties; it can be employed based on the information from readily available robotic ultrasound platforms.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 19
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose This study describes a method for measuring the accuracy of the virtual impression. Methods In vitro measurements according to a metrological approach were based on (1) use of an opto-mechanical coordinate measuring machine to acquire 3D points from a master model, (2) the mathematical reconstruction of regular geometric features (planes, cylinders, points) from 3D points or an STL file, and (3) consistent definition and evaluation of position and distance errors describing scanning inaccuracies. Two expert and two inexpert operators each made five impressions. The 3D position error, with its relevant X , Y , and Z components, the mean 3D position error of each scanbody, and the intra-scanbody distance error were measured using the analysis of variance and the Sheffe’s test for multiple comparison. Results Statistically significant differences in the accuracy of the impression were observed among the operators for each scanbody, despite the good reliability (Cronbach’s $$\alpha$$ = 0.897). The mean 3D position error of the digital impression was between 0.041 ± 0.023 mm and 0.082 ± 0.030 mm. Conclusions Within the limitations of this in vitro study, which was performed using a single commercial system for preparing digital impressions and one test configuration, the data showed that the digital impressions had a level of accuracy comparable to that reported in other studies, and which was acceptable for clinical and technological applications. The distance between the individual positions (#36 to #46) of the scanbody influenced the magnitude of the error. The position error generated by the intraoral scanner was dependent on the length of the arch scanned. Operator skill and experience may influence the accuracy of the impression.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 20
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Technical advancements have been part of modern medical solutions as they promote better surgical alternatives that serve to the benefit of patients. Particularly with cardiovascular surgeries, robotic surgical systems enable surgeons to perform delicate procedures on a beating heart, avoiding the complications of cardiac arrest. This advantage comes with the price of having to deal with a dynamic target which presents technical challenges for the surgical system. In this work, we propose a solution for cardiac motion estimation. Methods Our estimation approach uses a variational framework that guarantees preservation of the complex anatomy of the heart. An advantage of our approach is that it takes into account different disturbances, such as specular reflections and occlusion events. This is achieved by performing a preprocessing step that eliminates the specular highlights and a predicting step, based on a conditional restricted Boltzmann machine, that recovers missing information caused by partial occlusions. Results We carried out exhaustive experimentations on two datasets, one from a phantom and the other from an in vivo procedure. The results show that our visual approach reaches an average minima in the order of magnitude of $$10^{-7}$$ while preserving the heart’s anatomical structure and providing stable values for the Jacobian determinant ranging from 0.917 to 1.015. We also show that our specular elimination approach reaches an accuracy of 99% compared to a ground truth. In terms of prediction, our approach compared favorably against two well-known predictors, NARX and EKF, giving the lowest average RMSE of 0.071. Conclusion Our approach avoids the risks of using mechanical stabilizers and can also be effective for acquiring the motion of organs other than the heart, such as the lung or other deformable objects.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 21
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Currently, intraoperative ultrasound in brain tumor surgery is a rapidly propagating option in imaging technology. We examined the accuracy and resolution limits of different ultrasound probes and the influence of 3D-reconstruction in a phantom and compared these results to MRI in an intraoperative setting (iMRI). Methods An agarose gel phantom with predefined gel targets was examined with iMRI, a sector (SUS) and a linear (LUS) array probe with two-dimensional images. Additionally, 3D-reconstructed sweeps in perpendicular directions were made of every target with both probes, resulting in 392 measurements. Statistical calculations were performed, and comparative boxplots were generated. Results Every measurement of iMRI and LUS was more precise than SUS, while there was no apparent difference in height of iMRI and 3D-reconstructed LUS. Measurements with 3D-reconstructed LUS were always more accurate than in 2D-LUS, while 3D-reconstruction of SUS showed nearly no differences to 2D-SUS in some measurements. We found correlations of 3D-reconstructed SUS and LUS length and width measurements with 2D results in the same image orientation. Conclusions LUS provides an accuracy and resolution comparable to iMRI, while SUS is less exact than LUS and iMRI. 3D-reconstruction showed the potential to distinctly improve accuracy and resolution of ultrasound images, although there is a strong correlation with the sweep direction during data acquisition.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 22
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose To develop a method for intra-patient registration of pre- and post-contrast abdominal MR images with large local deformations and large intensity variations. Method A hybrid method is proposed to deal with this problem. It consists of two coupled techniques: (1) descriptor matching (DM) at the original resolution using a discrete optimization strategy to avoid getting trapped in a local minimum; (2) continuous optimization to refine the registration outcome based on autocorrelation of local image structure (ALOST). Our method—called DM-ALOST—has become insensitive to the local uptake of contrast agent by exploiting the mean phase and the phase congruency extracted from the multi-scale monogenic signal. The method was extensively tested on abdominal MR data of 30 patients with Crohn’s disease. Results DM-ALOST produced significantly larger mean Dice coefficients than two state-of-the-art methods $$({p}〈0.05)$$ . Conclusion Both qualitative and quantitative tests demonstrated improved registration using the proposed method compared to the state-of-the-art. The DM-ALOST method facilitates measurement of corresponding features from different abdominal MR images, which can aid to assess certain diseases, particularly Crohn’s disease.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 23
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose The target registration error (TRE) is a crucial parameter to estimate the potential usefulness of computer-assisted navigation intraoperatively. Both image-to-patient registration on base of rigid-body registration and TRE prediction methods are available for spatially isotropic and anisotropic data. This study presents a thorough validation of data obtained in an experimental operating room setting with CT images. Methods Optical tracking was used to register a plastic skull, an anatomic specimen, and a volunteer to their respective CT images. Plastic skull and anatomic specimen had implanted bone fiducials for registration; the volunteer was registered with anatomic landmarks. Fiducial localization error, fiducial registration error, and total target error (TTE) were measured; the TTE was compared to isotropic and anisotropic error prediction models. Numerical simulations of the experiment were done additionally. Results The user localization error and the TTE were measured and calculated using predictions, both leading to results as expected for anatomic landmarks and screws used as fiducials. TRE/TTE is submillimetric for the plastic skull and the anatomic specimen. In the experimental data a medium correlation was found between TRE and target localization error (TLE). Most of the predictions of the application accuracy (TRE) fall in the 68% confidence interval of the measured TTE. For the numerically simulated data, a prediction of TTE was not possible; TRE and TTE show a negligible correlation. Conclusion Experimental application accuracy of computer-assisted navigation could be predicted satisfactorily with adequate models in an experimental setup with paired-point registration of CT images to a patient. The experimental findings suggest that it is possible to run navigation and prediction of navigation application accuracy basically defined by the spatial resolution/precision of the 3D tracker used.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 24
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Identifying the elbow flexion–extension (F–E) movement axis is important for placing a hinged elbow external fixator. An X-ray fluoroscopy-based method is widely used in clinical practice, exposing the patient and surgeons to high doses of radiation. Additionally, the accuracy and repeatability of the fluoroscopy-based method are very low and affected by subjective factors. Methods To solve this problem, an X-ray-free method based on kinematics analysis was proposed to identify the elbow F–E movement axis, and a navigation system was built to guide the placement of the elbow external fixator. Results Our X-ray-free navigation method is more repeatable than the current X-ray fluoroscopy method used clinically. Both our algorithm and the NIST (National Institute of Standards and Technology) algorithm showed high accuracy and repeatability to identify the axis. Conclusions The method proposed in this study is very promising to avoid a large dose of X-ray radiation and increases the repeatability and performance of identifying the elbow F–E movement axis for the placement of the hinged elbow external fixator.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 25
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Complete resection of diseased lesions reduces the recurrence of cancer, making it critical for surgical treatment. However, precisely resecting residual tumors is a challenge during operation. A novel integrated spectral-domain optical-coherence-tomography (SD-OCT) and laser-ablation therapy system for soft-biological-tissue resection is proposed. This is a prototype optical integrated diagnosis and therapeutic system as well as an optical theranostics system. Methods We develop an optical theranostics system, which integrates SD-OCT, a laser-ablation unit, and an automatic scanning platform. The SD-OCT image of biological tissue provides an intuitive and clear view for intraoperative diagnosis and monitoring in real time. The effect of laser ablation is analyzed using a quantitative mathematical model. The automatic endoscopic scanning platform combines an endoscopic probe and an SD-OCT sample arm to provide optical theranostic scanning motion. An optical fiber and a charge-coupled device camera are integrated into the endoscopic probe, allowing detection and coupling of the OCT-aiming beam and laser spots. Results The integrated diagnostic and therapeutic system combines SD-OCT imaging and laser-ablation modules with an automatic scanning platform. OCT imaging, laser-ablation treatment, and the integration and control of diagnostic and therapeutic procedures were evaluated by performing phantom experiments. Furthermore, SD-OCT-guided laser ablation provided precision laser ablation and resection for the malignant lesions in soft-biological-tissue-lesion surgery. The results demonstrated that the appropriate laser-radiation power and duration time were 10 W and 10 s, respectively. In the laser-ablation evaluation experiment, the error reached approximately 0.1 mm. Another validation experiment was performed to obtain OCT images of the pre- and post-ablated craters of ex vivo porcine brainstem. Conclusion We propose an optical integrated diagnosis and therapeutic system. The primary experimental results show the high efficiency and feasibility of our theranostics system, which is promising for realizing accurate resection of tumors in vivo and in situ in the future.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 26
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose We propose a novel framework for enhancement and localization of steeply inserted hand-held needles under in-plane 2D ultrasound guidance. Methods Depth-dependent attenuation and non-axial specular reflection hinder visibility of steeply inserted needles. Here, we model signal transmission maps representative of the attenuation probability within the image domain. The maps are employed in a contextual regularization framework to recover needle shaft and tip information. The needle tip is automatically localized by line-fitting along the local-phase-directed trajectory, followed by statistical optimization. Results The proposed method was tested on 300 ex vivo ultrasound scans collected during insertion of an epidural needle into freshly excised porcine and bovine tissue. A tip localization accuracy of $$0.55\pm 0.06\,\hbox {mm}$$ was achieved. Conclusion The proposed method could be useful in challenging procedures where needle shaft and tip are inconspicuous. Improved needle localization results compared to previously proposed methods suggest that the proposed method is promising for further clinical evaluation.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 27
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Complications in wound healing after neurosurgical operations occur often due to scarred dehiscence with skin blood perfusion disturbance. The standard imaging method for intraoperative skin perfusion assessment is the invasive indocyanine green video angiography (ICGA). The noninvasive dynamic infrared thermography (DIRT) is a promising alternative modality that was evaluated by comparison with ICGA. Methods The study was carried out in two parts: (1) investigation of technical conditions for intraoperative use of DIRT for its comparison with ICGA, and (2) visual and quantitative comparison of both modalities in a proof of concept on nine patients. Time–temperature curves in DIRT and time–intensity curves in ICGA for defined regions of interest were analyzed. New perfusion parameters were defined in DIRT and compared with the usual perfusion parameters in ICGA. Results The visual observation of the image data in DIRT and ICGA showed that operation material, anatomical structures and skin perfusion are represented similarly in both modalities. Although the analysis of the curves and perfusion parameter values showed differences between patients, no complications were observed clinically. These differences were represented in DIRT and ICGA equivalently. Conclusions DIRT has shown a great potential for intraoperative use, with several advantages over ICGA. The technique is passive, contactless and noninvasive. The practicability of the intraoperative recording of the same operation field section with ICGA and DIRT has been demonstrated. The promising results of this proof of concept provide a basis for a trial with a larger number of patients.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 28
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose Basic surgical skills of suturing and knot tying are an essential part of medical training. Having an automated system for surgical skills assessment could help save experts time and improve training efficiency. There have been some recent attempts at automated surgical skills assessment using either video analysis or acceleration data. In this paper, we present a novel approach for automated assessment of OSATS-like surgical skills and provide an analysis of different features on multi-modal data (video and accelerometer data). Methods We conduct a large study for basic surgical skill assessment on a dataset that contained video and accelerometer data for suturing and knot-tying tasks. We introduce “ entropy-based ” features— approximate entropy and cross-approximate entropy , which quantify the amount of predictability and regularity of fluctuations in time series data. The proposed features are compared to existing methods of Sequential Motion Texture, Discrete Cosine Transform and Discrete Fourier Transform , for surgical skills assessment. Results We report average performance of different features across all applicable OSATS-like criteria for suturing and knot-tying tasks. Our analysis shows that the proposed entropy-based features outperform previous state-of-the-art methods using video data, achieving average classification accuracies of 95.1 and 92.2% for suturing and knot tying, respectively. For accelerometer data, our method performs better for suturing achieving 86.8% average accuracy. We also show that fusion of video and acceleration features can improve overall performance for skill assessment. Conclusion Automated surgical skills assessment can be achieved with high accuracy using the proposed entropy features. Such a system can significantly improve the efficiency of surgical training in medical schools and teaching hospitals.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 29
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose A personalized estimation of the cochlear shape can be used to create computational anatomical models to aid cochlear implant (CI) surgery and CI audio processor programming ultimately resulting in improved hearing restoration. The purpose of this work is to develop and test a method for estimation of the detailed patient-specific cochlear shape from CT images. Methods From a collection of temporal bone $$\mu$$ CT images, we build a cochlear statistical deformation model (SDM), which is a description of how a human cochlea deforms to represent the observed anatomical variability. The model is used for regularization of a non-rigid image registration procedure between a patient CT scan and a $$\mu$$ CT image, allowing us to estimate the detailed patient-specific cochlear shape. Results We test the accuracy and precision of the predicted cochlear shape using both $$\mu$$ CT and CT images. The evaluation is based on classic generic metrics, where we achieve competitive accuracy with the state-of-the-art methods for the task. Additionally, we expand the evaluation with a few anatomically specific scores. Conclusions The paper presents the process of building and using the SDM of the cochlea. Compared to current best practice, we demonstrate competitive performance and some useful properties of our method.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 30
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose This work aims to develop a unified methodology for the false positives reduction in lung nodules computer-aided detection schemes. Methods The 3D region of each detected nodule candidate is first reconstructed using the sparse field method for accurately segmenting the objects. This technique enhances the level set modeling by restricting the computations to a narrow band near the evolving curve. Then, a set of 2D and 3D relevant features are extracted for each segmented candidate. Subsequently, a hybrid undersampling/boosting algorithm called RUSBoost is applied to analyze the features and discriminate real nodules from non-nodules. Results The performance of the proposed scheme was evaluated by using 70 CT images, randomly selected from the Lung Image Database Consortium and containing 198 nodules. Applying RUSBoost classifier exhibited a better performance than some commonly used classifiers. It effectively reduced the average number of FPs to only 3.9 per scan based on a fivefold cross-validation. Conclusion The practical implementation, applicability for different nodule types and adaptability in handling the imbalanced data classification insure the improvement in lung nodules detection by utilizing this new approach.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 31
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose In brain tumor surgeries, maximum removal of cancerous tissue without compromising normal brain functions can improve the patient’s survival rate and therapeutic benefits. To achieve this, diffusion MRI and intra-operative ultrasound (iUS) can be highly instrumental. While diffusion MRI allows the visualization of white matter tracts and helps define the resection plan to best preserve the eloquent areas, iUS can effectively track the brain shift after craniotomy that often renders the pre-surgical plan invalid, ensuring the accuracy and safety of the intervention. Unfortunately, brain shift correction using iUS and automatic registration has never been shown for brain tractography so far despite its rising significance in brain tumor resection. Methods We employed a correlation-ratio-based nonlinear registration algorithm to account for brain shift through MRI–iUS registration and used the recovered deformations to warp both the brain anatomy and tractography seen in pre-surgical plans. The overall technique was demonstrated retrospectively on four patients who underwent iUS-guided low-grade brain gliomas resection. Results Through qualitative and quantitative evaluations, the preoperative MRI and iUS scans were well realigned after nonlinear registration, and the deformed brain tumor volumes and white matter tracts showed large displacements away from the pre-surgical plans. Conclusions We are the first to demonstrate the technique to track nonlinear deformation of brain tractography using real clinical MRI and iUS data, and the results confirm the need for updating white matter tracts due to tissue shift during surgery.
Print ISSN: 1861-6410
Electronic ISSN: 1861-6429
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 32
Unknown
Springer
Publication Date: 2018-03-06
Description: The NW–SE trending Zagros orogenic belt was initiated during the convergence of the Afro–Arabian continent and the Iranian microcontinent in the Late Cretaceous. Ongoing convergence is confirmed by intense seismicity related to compressional stresses collision-related in the Zagros orogenic belt by reactivation of an early extensional faulting to latter compressional segmented strike–slip and dip–slip faulting. These activities are strongly related either to the deep-seated basement fault activities (deep-seated earthquakes) underlies the sedimentary cover or gently dipping shallow-seated décollement horizon of the rheological weak rocks of the infra-Cambrian Hormuz salt. The compressional stress regimes in the different units play an important role in controlling the stress conditions between the different units within the sedimentary cover and basement. A significant set of nearly N–S trending right-lateral strike–slip faults exists throughout the study area in the Fars area in the Zagros Foreland Folded Belt. Fault–slip and focal mechanism data were analyzed using the stress inversion method to reconstruct the paleo and recent stress conditions. The results suggest that the current direction of maximum principal stress averages N19°E, with N38°E that for the past from Cretaceous to Tertiary (although a few sites on the Kar-e-Bass fault yield a different direction). The results are consistent with the collision of the Afro–Arabian continent and the Iranian microcontinent. The difference between the current and paleo-stress directions indicates an anticlockwise rotation in the maximum principle stress direction over time. This difference resulted from changes in the continental convergence path, but was also influenced by the local structural evolution, including the lateral propagation of folds and the presence of several local décollement horizons that facilitated decoupling of the deformation between the basement and the sedimentary cover. The obliquity of the maximum compressional stress into the fault trends reveals a typical stress partitioning of thrust and strike–slip motion in the Kazerun, Kar-e-Bass, Sabz-Pushan, and Sarvestan fault zones that caused these fault zones behave as segmented strike–slip and dip–slip faults.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 33
Unknown
Springer
Publication Date: 2018-03-06
Description: The Zhunsujihua porphyry molybdenum deposit, located in northern Inner Mongolia of China that belongs to Central-Asian Orogenic Belt (CAOB), is the only Mo deposit formed in the late Carboniferous in this area so far. Its mineralization is mainly restricted to the Zhunsujihua granitoid intrusions, which are composed of the main granodiorite (GD) and crosscutting, virtually coeval minor syn-ore leucogranite (LG) and diorite porphyry (DP) dykes. LA-ICP-MS zircon U–Pb dating yields crystallization ages of 300.0 ± 2.0, 299.3 ± 2.0, and 299.0 ± 2.6 Ma for the GD, LG, and DP, respectively. The major and trace element lithogeochemical data show that the GD and LG are metaluminous to weakly peraluminous, high-K calc-alkaline series with I-type granite characteristics, strongly oxidized, with low concentrations of Ba, Nb, Sr, P, and Ti and elevated K and Rb contents, indicating typical arc magmatic features. The LG is a product derived by extensive fractional crystallization of a parental magma similar to the GD as evident from the lower Eu/Eu*, Nb/Ta, Zr/Hf, and T Zr . The moderately altered DP exhibits high concentrations of K, Rb, Cs, LREE, Y, and low Sr/Y, with a positive ε Nd (300 Ma), which indicates a mantle or juvenile source associated with an arc setting. The Sr–Nd–Hf isotope data show low I Sr (0.70406–0.70461) and moderate ε Nd (300 Ma) (−0.9 to 1.5) for the GD and LG, and relatively high ε Hf (300 Ma) values (−3.6 to +11.2) for the GD, suggesting the magma mainly originated from the juvenile lower crust that was derived from depleted mantle, with a minor component of ancient continental crust. Lead isotope data have characteristics of a lower crust source with minor contamination by upper crustal material. Combined with previous research, the Zhunsujihua granitoid intrusions developed in an intracontinental volcanic arc (Uliastai) associated with northward subduction of the Paleo-Asian Ocean plate during late Carboniferous to early Permian; this suggests that the subduction of Paleo Asian Ocean may have continued to late Carboniferous, and the Hengenshan basin is probably closed during the early Permian. Fractional crystallization is the main evolutionary process of the felsic magma, which has played an important role in the Mo mineralization. The coeval DP may have provided additional heat for the extended evolution of the crystallizing felsic magma chamber.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 34
Unknown
Springer
Publication Date: 2018-03-06
Description: The Mesozoic orogeny in Central Qiangtang Metamorphic Belt, northern Tibet, provides important insights into the geological evolution of the Paleo-Tethys Ocean. However, the Triassic–early Jurassic tectonics, particularly those associated with the continental collisionstage, remains poorly constrained. Here we present results from geological mapping, structural analysis, P–T data, and Ar–Ar geochronology of the Mayer Kangri metamorphic complex. Our data reveal an E–W-trending, ~2 km wide dome-like structure associated with four successive tectonic events during the Middle Triassic and Early Jurassic. Field observations indicate that amphibolite and phengite schist complexes in this complex are separated from the overlying lower greenschist mélange by normal faulting with an evident dextral shearing component. Open antiform-like S 2 foliation of the footwall phengite schist truncates the approximately north-dipping structures of the overlying mélange. Microtextures and mineral chemistry of amphibole reveal three stages of growth: Geothermobarometric estimates yield temperatures and pressures of 524 °C and 0.88 GPa for pargasite cores, 386 °C and 0.34 GPa for actinolite mantles, and ~404 °C and 0.76 GPa for winchite rims. Peak blueschist metamorphism in the phengite schist occurred at ~0.7–1.1 GPa and ~400 °C. Our Ar–Ar dating of amphibole reveals rim-ward decreasing in age bands, including ~242.4–241.2 Ma, ≥202.6–196.8, and 192.9–189.8 Ma. The results provide evidence for four distinct phases of Mesozoic tectonic evolution in Central Qiangtang: (1) northward oceanic subduction beneath North Qiangtang (~244–220 Ma); (2) syn-collisional slab-break off (223–202 Ma); (3) early collisional extension driven by buoyant extrusion flow from depth (~202.6–197 Ma); and (4) post-collision contraction and reburial (195.6–188.7 Ma).
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 35
Unknown
Springer
Publication Date: 2018-03-06
Description: Here we present detrital apatite fission track (AFT), zircon fission track (ZFT) and a few apatite (U–Th)/He (AHe) data of Middle Pleistocene to modern Rhine, Meuse and Elbe river sediments in order to resolve processes that control detrital age distributions (provenance, erosion and mineral fertility). We used a modelling approach to compare observed with theoretically predicted age distributions from an interpolated in situ AFT and ZFT age map. In situ cooling ages do show large differences in the Rhine drainage basin, facilitating the differentiation between different source regions. Inconsistencies between observed and theoretical age distributions of the Meuse and Elbe samples can be explained by mixing and reworking of sediments with different provenances (Meuse Middle Pleistocene terrace sediment) and a yet unexplored source region with old AFT ages (Elbe samples). Overall, the results show that detrital thermochronology is capable of identifying the provenance of Middle Pleistocene to modern sediments. The AFT age distributions of Rhine sediments are dominated (~70%) by AFT ages representing the Alps. A possible explanation is higher erosion rates in the Alps as compared to areas outside the Alps. A Late Pleistocene sample from the Upper Rhine Graben contains apatite grains from the Molasse and Hegau volcanics, which we explain with a shift of the headwaters of the Rhine to the north as a result of intense Middle Pleistocene Riss glaciation. Contrary to the observed dominance of Alpine-derived AFT ages in Rhine sediments, the relative contribution of zircon ages with sources in the Alps is lower and significantly decreases downstream, suggesting a major source of zircons outside the Alps. This can be explained by increased zircon fertility of sediments derived from the Rhenish massif. Therefore, we conclude that erosion and mineral fertility are the main processes controlling detrital AFT and ZFT age distributions of the sampled river sediment. In case of the Rhine samples, AFT age distributions are mainly controlled by differences in erosion rates, whereas this impact is completely balanced by differences in mineral fertility for the ZFT data.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 36
Unknown
Springer
Publication Date: 2018-03-06
Description: This paper presents precise zircon U–Pb, bulk-rock geochemical, and Sr–Nd–Pb isotopic data for metagabbro, quartz diorite, and granite units within the Tengchong Block of SW China, which forms the southeastern extension of the Himalayan orogeny and the southwestern section of the Sanjiang orogenic belt, a key region for furthering our understanding of the evolution of the eastern Paleo-Tethys. These data reveal four groups of zircon U–Pb ages that range from the late Paleozoic to the early Mesozoic, including a 263.6 ± 3.6 Ma quartz diorite, a 218.5 ± 5.4 Ma two-mica granite, a 205.7 ± 3.1 Ma metagabbroic unit, and a 195.5 ± 2.2 Ma biotite granite. The quartz diorite in this area contains low concentrations of SiO 2 (60.71–64.32 wt%), is sodium-rich, and is metaluminous, indicating formation from magmas generated by a mixed source of metamafic rocks with a significant metapelitic sedimentary material within lower arc crust. The two-mica granites contain high concentrations of SiO 2 (73.2–74.3 wt%), are strongly peraluminous, and have evolved Sr–Nd–Pb isotopic compositions, all of which are indicative of a crustal source, most probably from the partial melting of felsic pelite and metagreywacke/psammite material. The metagabbros contain low concentrations of SiO 2 (50.17–50.96 wt%), are sodium-rich, contain high concentrations of Fe 2 O 3 T (9.79–10.06 wt%) and CaO (6.88–7.12 wt%), and are significantly enriched in the Sr (869–894 ppm) and LREE (198.14–464.60 ppm), indicative of derivation from magmas generated by a metasomatized mantle wedge modified by the sedimentary-derived component. The biotite granites are weakly peraluminous and formed from magmas generated by melting of metasedimentary sources dominated by metagreywacke/psammite material. Combining the petrology and geochemistry of these units with the regional geology of the Indosinian orogenic belt provides evidence for two stages of magmatism: an initial stage that generated magmas during partial melting of mantle-derived material associated with late Permian-to-Early Triassic subduction of the Paleo-Tethys, and a second stage that generated granitoid magmas by the partial melting of crustal-derived sources during the Late Triassic collision between the Lhasa and Tengchong blocks and the northern margin of the Australian continent. These rocks, therefore, provide evidence of a systematic late Permian-to-Late Triassic transition from a pre-collision/volcanic arc setting through a collisional setting to a final within-plate phase of magmatism. The previous research involving bulk-rock Sr–Nd analyses of units from the southern Sanjiang orogenic belt and zircon Hf isotopic analyses of units from the Tengchong Block suggests that these areas may record similar magmatic evolutionary trends from mantle- to crustal-derived sources during the evolution of the eastern Paleo-Tethys.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 37
Unknown
Springer
Publication Date: 2018-03-06
Description: Background This study aimed to investigate the efficacy of docetaxel in castration-resistant prostate cancer (CRPC) patients with intraductal carcinoma of the prostate (IDC-P). Patients and methods We retrospectively identified 79 CRPC patients with distant metastasis at initial diagnosis from June 2002 to January 2014. All patients received initial androgen deprivation therapy and 46 received docetaxel chemotherapy after progressing to CRPC. The primary outcome of interest was cancer-specific survival (CSS) from the time of CRPC diagnosis. The Cox regression model was used to confirm whether IDC-P and docetaxel would act as independent factors for prognosis. Results IDC-P was found in 62 of 79 patients. The median CSS in the IDC-P-present group was 18.2 versus 45.6 months in the IDC-P-absent group (HR 2.67; 95% CI 1.18 to 6.06; P  = 0.019). Docetaxel was administered to 36 patients with IDC-P and 10 patients without IDC-P, with a median CSS of 20.5 versus 53.2 months, respectively (HR 2.98; 95% CI 1.02 to 8.64; P  = 0.044). Multivariate analysis demonstrated that the presence of IDC-P and docetaxel were independent prognostic factors for CSS ( P  = 0.026 and 0.005, respectively) and overall survival (OS) ( P  = 0.029 and 0.001, respectively). Conclusion The presence of IDC-P is an independent prognostic factor in CRPC patients with distant metastases and IDC-P in needle biopsies at the time of initial diagnosis. Docetaxel may prolong CSS and OS in CRPC patients with distant metastases and IDC-P in needle biopsies at the time of initial diagnosis.
Print ISSN: 1341-9625
Electronic ISSN: 1437-7772
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 38
Unknown
Springer
Publication Date: 2018-03-06
Description: Background This study was performed to assess the efficacy and feasibility of definitive chemoradiotherapy consisting of weekly doses of combined paclitaxel and carboplatin concurrent with radiation therapy, followed by 2 cycles of consolidation chemotherapy for advanced esophageal carcinoma. Methods Eligibility criteria included local, advanced, newly diagnosed and postoperative local regional lymph node metastasis; Eastern Cooperative Oncology Group (ECOG) score ≤ 2; and adequate organ function. Patients received concurrent chemoradiation therapy consisting of radiotherapy (50.4 Gy/28 Fx or 61.2 Gy/34 Fx) and concurrent paclitaxel (50 mg/m 2 ) and carboplatin (area under the curve, AUC = 2) on days 1, 8, 15, 22 and 29. The two-cycle consolidation chemotherapy protocol was paclitaxel (175 mg/m 2 ) plus carboplatin (AUC = 5) administered on days 57 and 85, after concurrent chemoradiotherapy. Results Between August 2013 and February 2015, 65 patients with oesophageal carcinoma were enrolled in the study; 34 (52.3%) were newly diagnosed and 31 (47.6%) had postoperative local regional lymph node metastasis. The median overall survival time was 21.7 months (95% confidence interval [CI] 16.7–26.6), and the median progression-free survival time was 12.1 months (95% CI 9.0–15.3). A total of 96.9% (63/65) and 67.6% (44/65) patients completed ≥5 cycles and all 7 cycles of chemotherapy, respectively. A total of 93.8% (61/65) patients completed radiation therapy. The 1- and 2-year overall survival rates were 73.7 and 42.0%, respectively. The 1- and 2-year progression-free survival rates were 50.6 and 31.1%, respectively. Grade 3–4 toxicity during chemoradiotherapy included neutropenia (24.5%), thrombocytopenia (4.6%), fatigue (1.5%), anaemia (1.5%), radiation dermatitis (1.5%), pneumonitis (1.5%), oesophagitis (4.6%) and vomiting (1.5%). Conclusions In patients with locally advanced oesophageal cancer, the combination of weekly doses of paclitaxel and carboplatin was well tolerated and produced comparable results. A three-arm randomised phase III trial (NCT02459457) comparing paclitaxel in combination with cisplatin, carboplatin or 5-fluorouracil with concurrent radiotherapy is on-going at our hospital.
Print ISSN: 1341-9625
Electronic ISSN: 1437-7772
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 39
Unknown
Springer
Publication Date: 2018-03-06
Description: Background The aim of this study was to investigate the prognostic significance of multiple preoperative laboratory abnormalities in upper urinary tract urothelial carcinoma (UUTUC) patients. Methods This study included a total of 135 consecutive patients with clinically localized UUTUC who underwent radical nephroureterectomy (RNU). The impact of several preoperative blood-based markers in addition to conventional clinical factors on extravesical recurrence-free survival (eRFS) in these patients was retrospectively evaluated. Results Despite the lack of a significant correlation between conventional clinical factors and any of the postoperative pathologic parameters, preoperative laboratory abnormalities were shown to have a significant impact on some pathological factors reflecting an aggressive phenotype as follows—C-reactive protein (CRP) level on pathological stage, De Ritis (aspartate transaminase/alanine transaminase) ratio on nodal involvement, and neutrophil−lymphocyte ratio (NLR) on pathological stage. During the observation period of this study (median 36.1 months), extravesical disease recurrence was detected in 44 (32.6%) of the 135 patients with a 5-year eRFS rate of 62.1%. Of several factors examined, the CRP level, De Ritis ratio, and NRL were significantly correlated with eRFS on univariate analysis. Of these significant factors, the De Ritis ratio and NRL were identified as independent predictors of eRFS on multivariate analysis. Moreover, there were significant differences in eRFS according to the positive numbers of these two independent risk factors. Conclusions These findings suggest that it is important to consider laboratory abnormalities, particularly the De Ritis ratio and NLR, to predict disease recurrence following RNU in patients with clinically localized UUTUC.
Print ISSN: 1341-9625
Electronic ISSN: 1437-7772
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 40
Unknown
Springer
Publication Date: 2018-03-06
Description: Background The prognostic implications of preoperative serum total cholesterol (TC) level in patients with renal cell carcinoma (RCC) remain poorly understood. We investigated the prognostic role of preoperative serum TC in patients with surgically treated RCC from a large, multi-institutional Korean collaboration. Patients and methods A database of 3064 patients with RCC who underwent radical or partial nephrectomy between 1999 and 2011 at eight academic centers was analyzed. Preoperative serum TC levels were measured in fasting blood samples. Results Low preoperative serum TC level was associated with aggressive tumor characteristics, including large tumor size, advanced stage, high nuclear grade, lymph node involvement, and sarcomatous differentiation (all P  〈 0.001). Low TC level was associated with poor recurrence-free or cancer-specific survival (CSS) in the entire cohort, whereas the significance of the association changed after stratification by disease stage and histologic subtype. Multivariate Cox regression analysis showed that preoperative TC, as a continuous or categorical variable, was an independent predictor of CSS. Conclusions Preoperative low serum TC level was associated with aggressive tumor characteristics and poor CSS in patients with surgically treated RCC. Preoperative TC may provide additional guidance regarding the choice of therapeutic strategies to improve prognosis.
Print ISSN: 1341-9625
Electronic ISSN: 1437-7772
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 41
Unknown
Springer
Publication Date: 2018-03-06
Description: Background The therapeutic significance of neoadjuvant chemotherapy (NAC) followed by radiation therapy (RT) was negated during the early 1990s. Here, we compared post-NAC RT to surgery for chemo-sensitive cervical squamous cell carcinoma (SCC). Methods This study included 79 consecutive patients with cervical SCC who were treated by NAC followed by surgery ( n  = 49) or by definitive RT ( n  = 30). We compared characteristics and survival outcomes between the surgery and RT groups by their responses to NAC. Results Of the 79 patients, 70 (89%) had stage II–IV disease and 41 (52%) had radiological pelvic lymph node enlargement. The 5-year disease-specific survival (DSS) rate of the entire cohort was 66.4% (median follow-up 54 months). Fifty-five patients (70%) achieved sufficient (complete or partial) responses to NAC. Among patients with insufficient NAC responses, the 5-year DSS rate of the surgery group (55.6%) was significantly higher than the RT group (20.0%; P  = 0.044). However, among patients with sufficient responses to NAC, 5-year DSS rates did not significantly differ between the surgery and RT groups (82.3 vs 78.6%; P  = 0.79) even though the RT group had many more unfavorable prognostic factors and received fewer subsequent treatments than the surgery group. Conclusions Post-NAC survival outcomes among patients with chemo-sensitive cervical SCC who then underwent RT were not inferior to those treated with surgery, and NAC did not detract from the efficacy of subsequent RT. Among selected patients who respond favorably to NAC, RT could be a less invasive substitute for surgery without compromising treatment outcomes.
Print ISSN: 1341-9625
Electronic ISSN: 1437-7772
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 42
Unknown
Springer
Publication Date: 2018-03-06
Description: A coupled thermo-mechanical bond-based peridynamical (TM-BB-PD) method is developed to simulate thermal cracking processes in rocks. The coupled thermo-mechanical model consists of two parts. In the first part, temperature distribution of the system is modeled based on the heat conduction equation. In the second part, the mechanical deformation caused by temperature change is calculated to investigate thermal fracture problems. The multi-rate explicit time integration scheme is proposed to overcome the multi-scale time problem in coupled thermo-mechanical systems. Two benchmark examples, i.e., steady-state heat conduction and transient heat conduction with deformation problem, are performed to illustrate the correctness and accuracy of the proposed coupled numerical method in dealing with thermo-mechanical problems. Moreover, two kinds of numerical convergence for peridynamics, i.e., m - and $$\delta$$ -convergences, are tested. The thermal cracking behaviors in rocks are also investigated using the proposed coupled numerical method. The present numerical results are in good agreement with the previous numerical and experimental data. Effects of PD material point distributions and nonlocal ratios on thermal cracking patterns are also studied. It can be found from the numerical results that thermal crack growth paths do not increases with changes of PD material point spacing when the nonlocal ratio is larger than 4. The present numerical results also indicate that thermal crack growth paths are slightly affected by the arrangements of PD material points. Moreover, influences of thermal expansion coefficients and inhomogeneous properties on thermal cracking patterns are investigated, and the corresponding thermal fracture mechanism is analyzed in simulations. Finally, a LdB granite specimen with a borehole in the heated experiment is taken as an application example to examine applicability and usefulness of the proposed numerical method. Numerical results are in good agreement with the previous experimental and numerical results. Meanwhile, it can be found from the numerical results that the coupled TM-BB-PD has the capacity to capture phenomena of temperature jumps across cracks, which cannot be captured in the previous numerical simulations.
Print ISSN: 0376-9429
Electronic ISSN: 1573-2673
Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Location Call Number Limitation Availability
Others were also interested in ...
• 43
Unknown
Springer
Publication Date: 2018-03-06
Description: Numerical simulation of void growth from thousands of randomly distributed particles is used to assess the functional dependence of the Gurson model. Shock loading of the model region followed by a ramped pressure release creates a smoothly varying velocity field in which the void growth is inertially stabilized. The pressure, effective stress, and void fraction are obtained from the simulation for comparison with the Gurson model. The results show that the pressure-void fraction relation from the model reasonably follows the simulation data, but the numerical data exhibit significantly greater void fraction dependence on the effective stress than the Gurson model.
Print ISSN: 0376-9429
Electronic ISSN: 1573-2673
Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Location Call Number Limitation Availability
Others were also interested in ...
• 44
Unknown
Springer
Publication Date: 2018-03-06
Description: RiskScape is a free multi-hazard risk assessment software programme jointly developed by GNS Science and the National Institute of Water and Atmospheric Research (NIWA) in New Zealand. RiskScape has a modular structure, with hazard layers, assets, and loss functions prepared separately. While RiskScape was originally developed for New Zealand, given suitable hazard and exposed asset information, RiskScape can be run anywhere in the world. Volcanic hazards are among the many hazards considered by RiskScape. We first present RiskScape’s framework for all hazards, and then describe in more detail the five volcanic hazards – tephra deposition, pyroclastic density currents, lava flows, lahars, and edifice construction/excavation. We describe how loss functions were selected and developed. We use a scenario example to illustrate not only how RiskScape’s volcanic module works but also how RiskScape can be used to compare across natural hazards.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 45
Unknown
Springer
Publication Date: 2018-03-06
Description: Global Synthetic Aperture Radar (SAR) measurements made over the past decades provide insights into the lateral extent of magmatic domains, and capture volcanic process on scales useful for volcano monitoring. Satellite-based SAR imagery has great potential for monitoring topographic change, the distribution of eruptive products and surface displacements (InSAR) at subaerial volcanoes. However, there are challenges in applying it routinely, as would be required for the reliable operational assessment of hazard. The deformation detectable depends upon satellite repeat time and swath widths, relative to the spatial and temporal scales of volcanological processes. We describe the characteristics of InSAR-measured volcano deformation over the past two decades, highlighting both the technique’s capabilities and its limitations as a monitoring tool. To achieve this, we draw on two global datasets of volcano deformation: the Smithsonian Institution Volcanoes of the World database and the Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics volcano deformation catalogue, as well as compiling some measurement characteristics and interpretations from the primary literature. We find that a higher proportion of InSAR observations capture non-eruptive and non-magmatic processes than those from ground-based instrument networks, and that both transient (〈 month) and long-duration (〉 5 years) deformation episodes are under-represented. However, satellite radar is already used to assess the development of extended periods of unrest and long-lasting eruptions, and improved spatial resolution and coverage have resulted in the detection of previously unrecognised deformation at both ends of the spatial scale (~ 10 to 〉 1000 km 2 ). ‘Baseline’ records of past InSAR measurements, including ‘null’ results, are fundamental for any future interpretation of interferograms in terms of hazard‚ both by providing information about past deformation at an individual volcano, and for assessing the characteristics of deformation that are likely to be detectable (and undetectable) using InSAR. More than half of all InSAR deformation signals attributed to magmatic processes have sources in the shallow crust (〈 5 km depth). While the depth distribution of InSAR-derived deformation sources is affected by measurement limitations, their lateral distribution provides information about the extent of active magmatic domains. Deformation is common (24% of all potentially magmatic events) at loci ≥5 km away from the nearest active volcanic vent. This demonstrates that laterally extensive active magmatic domains are not exceptional, but can comprise the shallowest part of trans-crustal magmatic systems in a range of volcanic settings.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 46
Unknown
Springer
Publication Date: 2018-03-06
Description: Accurately predicting lava flow path behavior is critical for active crisis management operations. The advance and emplacement of pāhoehoe flows modifies and inverts pre-existing topography, prompting the need for rapid and accurate updates to the topographic models used to forecast flow paths. The evolution and velocity of pāhoehoe flows are dependent on macro and micro topography, the slope of the descent path, effusion rate, and rheology. During the 2014–2015 Pāhoa crisis on the island of Hawai‘i, we used a low-altitude unmanned aerial system (UAS) to quickly and repeatedly image the active front of a slowly advancing pāhoehoe lava flow. This imagery was used to generate a series of 1 m resolution bare-earth digital elevation models (DEMs) and associated paths of steepest descent over the study area. The spatial resolution and timeliness of these UAS-derived models are an improvement over the existing topographic data used by managers during the crisis. Results from a stepwise resampling experiment suggest that the optimum DEM resolution for generating accurate pāhoehoe flow paths through lowland tropical forest environments is between 1 and 3 m. Our updated models show that future flows in this area will likely be deflected by these newly emplaced flows, possibly threatening communities not directly impacted by the original 2014–2015 lava flow. We demonstrate the value of deploying UAS during a dynamic volcanic crisis and suggest that this technology can fill critical monitoring gaps for Kīlauea and other active volcanoes worldwide.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 47
Unknown
Springer
Publication Date: 2018-03-06
Description: Volcanoes can produce far-reaching hazards that extend distances of tens or hundreds of kilometres in large eruptions, or in certain conditions for smaller eruptions. About a tenth of the world’s population lives within the potential footprint of volcanic hazards and lives are regularly lost through volcanic activity: volcanic fatalities were recorded in 18 of the last 20 years. This paper identifies the distance and distribution of fatalities around volcanoes and the activities of the victims at the time of impact, sourced from an extensive search of academic and grey literature, including media and official reports. We update and expand a volcano fatality database to include all data from 1500 AD to 2017. This database contains 635 records of 278,368 fatalities. Each record contains information on the number of fatalities, fatal cause, incident date and the fatality location in terms of distance from the volcano. Distance data were previously available in just 5% of fatal incidents: these data have been significantly increased to 72% (456/635) of fatal incidents, with fatalities recorded from inside the crater to more than 100 km from the summit. Local residents are the most frequently killed, but tourists, volcanologists and members of the media are also identified as common victims. These latter groups and residents of small islands dominate the proximal fatality record up to 5 km from the volcano. Though normally accounting for small numbers of fatalities, ballistics are the most common cause of fatal incidents at this distance. Pyroclastic density currents are the dominant fatal cause at 5 to 15 km. Lahars, tsunami and tephra dominate the record after about 15 km. The new location data are used to characterise volcanic threat with distance, as a function of eruption size and hazard type, and to understand how certain activities increase exposure and the likelihood of death. These findings support assessment of volcanic threat, population exposure and vulnerabilities related to occupation or activity.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 48
Unknown
Springer
Publication Date: 2018-03-06
Description: Surface transportation networks are critical infrastructure that are frequently affected by volcanic ash fall. Disruption to surface transportation from volcanic ash is often complex with the severity of impacts influenced by a vast array of parameters including, among others, ash properties such as particle size and deposit thickness, meteorological conditions, pavement characteristics, and mitigation actions. Fragility functions are used in volcanic risk assessments to express the conditional probability that an impact or loss state will be reached or exceeded for a given hazard intensity. Most existing fragility functions for volcanic ash adopt ash thickness as the sole hazard intensity metric that determines thresholds for functional loss. However, the selection of appropriate hazard intensity metrics has been highlighted as a crucial factor for fragility function development and recent empirical evidence suggests that ash thickness is not always the most appropriate metric. We review thresholds of functional loss for existing published surface transportation (i.e. road rail, maritime and airport) fragility functions that use ash thickness. We then refine these existing functions through the application of results from a series of recent laboratory experiments, which investigate the impacts of volcanic ash on surface transportation. We also establish new fragility thresholds and functions, which applies ash-settling rate as a hazard intensity metric. The relative importance of alternative hazard intensity metrics to surface transportation disruption is assessed with a suggested approach to account for these in existing fragility functions. Our work demonstrates the importance of considering ash-settling rate, in addition to ash thickness, as critical hazard intensity metrics for surface transportation, but highlights that other metrics, especially particle size, are also important for transportation. Empirical datasets, obtained from both post-eruption field studies and additional laboratory experimentation, will provide future opportunities to refine fragility functions. Our findings also justify the need for rapid and active monitoring and modelling of various ash characteristics (i.e. not ash thickness alone) during volcanic eruptions, particularly as potential disruption to surface transportation can occur with only ~ 0.1 mm of ash accumulation.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 49
Unknown
Springer
Publication Date: 2018-03-06
Description: Volcanologists make hazard forecasts in order to contribute to volcanic risk assessments and decision-making, in areas where volcanic phenomena have the potential to impact societal assets. Present-day forecasts related to the potential occurrence of an eruption mostly take the form of alert levels, that are established by volcano scientists with the aim of communicating the state of a volcano and its possible short-term evolution. Here I analyse current alert level systems and their role in decision-making processes. I show that the use of such systems implies predictive capabilities not supported by corresponding levels of confidence in the knowledge of the volcano. Their use also implies an assumption of volcano scientist responsibility for decisions that goes beyond the expertise of the scientist, and which, in most countries, is not granted by a corresponding societal mandate. A rational volcanic hazard forecast system accepts instead the uncertain nature of volcanic processes and the consequent limited predictive capabilities; forecasts expressed as probabilities, or better as probability distributions, reflect a rational attitude by scientists and assure clear roles that reflect both expertise and societal mandate to any group involved in the management of a volcanic crisis. Exceptions where the use of volcanic alert levels may lead to efficient management are also discussed.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 50
Unknown
Springer
Publication Date: 2018-03-06
Description: Volcanic risk assessment using probabilistic models is increasingly desired for risk management, particularly for loss forecasting, critical infrastructure management, land-use planning and evacuation planning. Over the past decades this has motivated the development of comprehensive probabilistic hazard models. However, volcanic vulnerability models of equivalent sophistication have lagged behind hazard modelling because of the lack of evidence, data and, until recently, minimal demand. There is an increasingly urgent need for development of quantitative volcanic vulnerability models, including vulnerability and fragility functions, which provide robust quantitative relationships between volcanic impact (damage and disruption) and hazard intensity. The functions available to date predominantly quantify tephra fall impacts to buildings, driven by life safety concerns. We present a framework for establishing quantitative relationships between volcanic impact and hazard intensity, specifically through the derivation of vulnerability and fragility functions. We use tephra thickness and impacts to key infrastructure sectors as examples to demonstrate our framework. Our framework incorporates impact data sources, different impact intensity scales, preparation and fitting of data, uncertainty analysis and documentation. The primary data sources are post-eruption impact assessments, supplemented by laboratory experiments and expert judgment, with the latter drawing upon a wealth of semi-quantitative and qualitative studies. Different data processing and function fitting techniques can be used to derive functions; however, due to the small datasets currently available, simplified approaches are discussed. We stress that documentation of data processing, assumptions and limitations is the most important aspect of function derivation; documentation provides transparency and allows others to update functions more easily. Following our standardised approach, a volcanic risk scientist can derive a fragility or vulnerability function, which then can be easily compared to existing functions and updated as new data become available. To demonstrate how to apply our framework, we derive fragility and vulnerability functions for discrete tephra fall impacts to electricity supply, water supply, wastewater and transport networks. These functions present the probability of an infrastructure site or network component equalling or exceeding one of four impact states as a function of tephra thickness.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 51
Unknown
Springer
Publication Date: 2018-03-06
Description: Many active European volcanoes and volcano observatories are island-based and located far from their administrative “mainland”. Consequently, Governments have developed multisite approaches, in which monitoring is performed by a network of individuals distributed across several national research centers. At a transnational level, multinational networks are also progressively emerging. Piton de la Fournaise (La Réunion Island, France) is one such example. Piton de la Fournaise is one of the most active volcanoes of the World, and is located at the greatest distance from its “mainland” than any other vulnerable “overseas” site, the observatory being 9365 km from its governing body in Paris. Effusive risk is high, so that a well-coordinated and rapid response involving near-real time delivery of trusted, validated and operational product for hazard assessment is critical. Here we review how near-real time assessments of lava flow propagation were developed using rapid provision, and update, of key source terms through a dynamic and open integration of near-real time remote sensing, modeling and measurement capabilities on both the national and international level. The multi-national system evolved during the five effusive crises of 2014–2015, and is now mature for Piton de la Fournaise. This review allows us to identify strong and weak points in an extended observatory system, and demonstrates that enhanced multi-national integration can have fundamental implications in scientific hazard assessment and response during an on-going effusive crisis.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 52
Unknown
Springer
Publication Date: 2018-03-06
Description: Mount Etna is Europe’s largest and most active volcano. In recent years, it has displayed enhanced explosive activity, causing concern amongst local inhabitants who frequently have to live with, and clean up, substantial ashfall. Basaltic volcanic ash is generally considered unlikely to be a respiratory health hazard due to its often coarse nature (with few particles sub-10 μm diameter) and lack of crystalline silica. However, a previous study by the authors showed the capability of basaltic ash to generate the hydroxyl radical, a highly-reactive species which may cause cell damage. That study investigated a single sample of Etna ash, amongst others, with data giving an early indication that the Etnean ash may be uniquely reactive. In this study, we analyse a suite of Etnean samples from recent and historical eruptions. Deposits indicate that Etna’s past history was much more explosive than current activity, with frequent sub-plinian to plinian events. Given the recent increase in explosivity of Etna, the potential hazard of similarly, or more-explosive, eruptions should be assessed. A suite of physicochemical analyses were conducted which showed recent ash, from 2001 and 2002 explosive phases, to be of similar composition to the historical deposits (trachy-basaltic) but rather coarser (〈 2.4 c.v.% sub-10 μm material and 〈11.5 c.v.% sub-10 μm material, respectively), but the potential for post-depositional fragmentation by wind and vehicles should not be ignored. One recent sample contained a moderate number of fibre-like particles, but all other samples were typical of fine-grained ash (blocky, angular with electrostatic or chemical aggregation of finer particles on larger ones). The surface reactivity analyses (Fenton chemistry, on samples from recent eruptions only) showed that Etnean ash is more reactive in hydroxyl radical generation than other basaltic ash, and samples of intermediate composition. This high reactivity suggests that Etnean ash could promote oxidative stress in exposed cells. Therefore, further investigation of the potential toxicity, through cellular tests, is now warranted in order to provide a comprehensive health hazard assessment.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 53
Unknown
Springer
Publication Date: 2018-03-06
Description: The preservation of thin (〈300 mm thick) tephra falls was investigated at four sites in Papua New Guinea (PNG), Alaska and Washington, USA. Measurements of the variations in the thickness of: (i) Tibito Tephra 150 km downwind from the source, Long Island (PNG) erupted mid-seventeenth century; (ii) St Helens W tephra (erupted 1479–80 A.D.) on the slopes of the adjacent Mt. Rainier in Washington State; (iii) Novarupta (1912) tephra preserved on Kodiak Island (Alaska, USA); and (iv) an experimentally placed tephra at a site near Mt. Hagen (PNG) allow tentative conclusions to be drawn about the relative importance to tephra preservation of slope gradients, vegetation cover and soil faunal activity. Results for the experimental tephra suggest that compaction occurs rapidly post-deposition and that estimates of tephra thickness and bulk density need to indicate how long after deposition thickness measurements were made. These studies show that erosional reworking of thin tephra is not rapid even on steeper slopes in high rainfall environments. In Papua New Guinea a 350-year old tephra is rarely present under forest but is well-preserved under alpine grasslands. On Mt. Rainier 500-year old tephra is readily preserved under forest but absent under grasslands as a result of gopher activity. Despite the poor relationship between tephra thickness and slope steepness the thickness of thin tephras is highly variable. On Kodiak Island thickness variability across a few metres is similar to that observed across the whole northeast of the island. The measured variability reported here indicates large sample sizes are necessary to adequately estimate the mean thickness of these thin tephra. These results have implications for the preparation of isopach maps, estimation of tephra volumes and elaboration of the potential consequences of tephra falls.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 54
Unknown
Springer
Publication Date: 2018-03-06
Description: Probabilistic quantification of lahar hazard is an important component of lahar risk assessment and mitigation. Here we propose a new approach to probabilistic lahar hazard assessment through coupling a lahar susceptibility model with a shallow-layer lahar flow model. Initial lahar volumes and their probabilities are quantified using the lahar susceptibility model which establishes a relationship between the volume of mobilised sediment and exceedance probabilities from rainfall intensity-frequency-duration curves. Rainfall-triggered lahar hazard zones can then be delineated probabilistically by using the mobilised volumes as an input into lahar flow models. While the applicability of this model is limited to rain-triggered lahars, this approach is able to reduce the reliance on historic and empirical estimates of lahar hazard and creates an opportunity for the generation of purely quantitative probabilistic lahar hazard maps. The new approach is demonstrated through the generation of probabilistic hazard maps for lahars originating from the Mangatoetoenui Glacier, Ruapehu volcano, New Zealand.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 55
Unknown
Springer
Publication Date: 2018-03-06
Description: Numerical simulations of lava flow emplacement are valuable for assessing lava flow hazards, forecasting active flows, designing flow mitigation measures, interpreting past eruptions, and understanding the controls on lava flow behavior. Existing lava flow models vary in simplifying assumptions, physics, dimensionality, and the degree to which they have been validated against analytical solutions, experiments, and natural observations. In order to assess existing models and guide the development of new codes, we conduct a benchmarking study of computational fluid dynamics (CFD) models for lava flow emplacement, including VolcFlow, OpenFOAM, FLOW-3D, COMSOL, and MOLASSES. We model viscous, cooling, and solidifying flows over horizontal planes, sloping surfaces, and into topographic obstacles. We compare model results to physical observations made during well-controlled analogue and molten basalt experiments, and to analytical theory when available. Overall, the models accurately simulate viscous flow with some variability in flow thickness where flows intersect obstacles. OpenFOAM, COMSOL, and FLOW-3D can each reproduce experimental measurements of cooling viscous flows, and OpenFOAM and FLOW-3D simulations with temperature-dependent rheology match results from molten basalt experiments. We assess the goodness-of-fit of the simulation results and the computational cost. Our results guide the selection of numerical simulation codes for different applications, including inferring emplacement conditions of past lava flows, modeling the temporal evolution of ongoing flows during eruption, and probabilistic assessment of lava flow hazard prior to eruption. Finally, we outline potential experiments and desired key observational data from future flows that would extend existing benchmarking data sets.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 56
Unknown
Springer
Publication Date: 2018-03-06
Description: We investigate whether the disproportionate contribution of individual volcanoes in the Large Magnitude Explosive Volcanic Eruption database (LaMEVE) potentially compromises the treatment of LaMEVE as a globally representative database of volcanic activity. We find that 41% of volcanoes which contribute at least one eruption to LaMEVE only contribute one eruption (10% of all eruptions), and the six most prolific volcanoes contribute 11% of eruptions. However, there is no systematic bias with respect to the eruption magnitude or date for volcanoes contributing one eruption. Also, no bias can be discerned for when the smallest or largest eruption at a volcano occurs in its eruptive record. Half of the volcanoes contributing one or more eruptions to the LaMEVE database had their first eruption prior to 36.4 ka. We find LaMEVE is representative – while there are well-known issues of eruption under-reporting, LaMEVE is not overly biased by the activity of a few volcanoes.
Electronic ISSN: 2191-5040
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 57
Unknown
Springer
Publication Date: 2018-03-06
Description: APEC blue was coined to describe the impact of short-term curbs on air pollution during the Asian-Pacific Economic Cooperation (APEC) Summit organized in Beijing in November 2014 and has been a hot topic among both general public and scientific sector in China. The consensus that gaseous agents NO 2 and SO 2 are greatly reduced in response to the control and restriction strategies implemented during the Summit period is shared by earlier literature. However, the re-examination of APEC blue conducted in the present study comes to a more contrasted conclusion. The remarkable drop in NO 2 abundances is confirmed in terms of both surface concentration and vertical column, whereas corresponding SO 2 changes are found to be marginal and not statistically significant, indicating that the decline of SO 2 was more tied to natural or random variability rather than externally forced. To explain the contrasted responses of NO 2 and SO 2 during the APEC summit, short-term variations of these species are further placed in the context of a longer term perspective, which reveals a striking contrast in the pathways of the secular tendency in NO 2 and SO 2 emissions and corresponding measured abundances of both pollutants. On the one hand, NO 2 emissions exhibit a sharp rise by 30–50% from 2006-2010 to 2011–2014; on the other hand, SO 2 emissions have undergone a gradual decrease in the last decade and have currently returned to their pre-2000 level. Therefore, short-term control measures are expected to be more effective in reducing the levels of NO 2 than SO 2 .
Print ISSN: 0167-7764
Electronic ISSN: 1573-0662
Topics: Chemistry and Pharmacology , Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 58
Unknown
Springer
Publication Date: 2018-03-06
Description: Ambient concentrations of organic carbon (OC), elemental carbon (EC) and water soluble inorganic ionic components (WSIC) of PM 10 were studied at Giridih, Jharkhand, a sub-urban site near the Indo Gangatic Plain (IGP) of India during two consecutive winter seasons (November 2011–February 2012 and November 2012–February 2013). The abundance of carbonaceous and water soluble inorganic species of PM 10 was recorded at the study site of Giridih. During winter 2011–12, the average concentrations of PM 10 , OC, EC and WSIC were 180.2 ± 46.4; 37.2 ± 6.2; 15.2 ± 5.4 and 18.0 ± 5.1 μg m −3 , respectively. Similar concentrations of PM 10 , OC, EC and WSIC were also recorded during winter 2012–13. In the present case, a positive linear trend is observed between OC and EC at sampling site of Giridih indicates the coal burning, as well as dispersed coal powder and vehicular emissions may be the source of carbonaceous aerosols. The principal components analysis (PCA) also identifies the contribution of coal burning  + soil dust, vehicular emissions + biomass burning and seconday aerosol to PM 10 mass concentration at the study site. Backward trajectoy and potential source contributing function (PSCF) analysis indicated that the aerosols being transported to Giridih from upwind IGP (Punjab, Haryana, Uttar Pradesh and Bihar) and surrounding region.
Print ISSN: 0167-7764
Electronic ISSN: 1573-0662
Topics: Chemistry and Pharmacology , Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 59
Unknown
Springer
Publication Date: 2018-03-06
Print ISSN: 0167-7764
Electronic ISSN: 1573-0662
Topics: Chemistry and Pharmacology , Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 60
Unknown
Springer
Publication Date: 2018-03-06
Description: Three online coupled chemical transport model simulations were analyzed for three summer months of 2015 in Poland. One of them was run with default emission inventory, the other two with NO x and VOC emissions reduced by 30%, respectively. Obtained ozone concentrations were evaluated with data from air quality measurement stations and ozone sensitivity to precursor emissions was estimated by ozone concentration differences between simulations and with the use of indicator ratios. They were calculated based on modeled mixing ratios of ozone, total reactive nitrogen and its components, nitric acid and hydrogen peroxide. The results show that the model overestimates ozone concentrations with the largest errors in the morning and evening, which is primarily related to the way vertical mixing is resolved by the model. Better model performance for ozone is achieved in rural than urban environment, as PBL and mixing mechanisms play more significant role in urban areas. Modeled ozone shows mixed sensitivity to precursor concentrations, similarly to other European regions, but indicator ratios have different values than are found in literature, particularly H 2 O 2 /HNO 3 is larger than in southern Europe. However, indicator ratios often differ between locations and transition values need to be established individually for a given region.
Print ISSN: 0167-7764
Electronic ISSN: 1573-0662
Topics: Chemistry and Pharmacology , Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 61
Unknown
Springer
Publication Date: 2018-03-06
Description: Nitrogen-containing organic compounds (NOC) formed from secondary organic aerosols (SOA) age via reaction with reduced nitrogen species are a vital class of brown carbon compounds. NOC compounds from ammonia (NH 3 ) gas-aging of benzene SOA were investigated in present study, and the experiments were performed by irradiating benzene/CH 3 ONO/NO/NH 3 air mixtures in a home-made smog chamber. The particulate NOC products of aged benzene SOA in the presence of NH 3 were measured by UV-Vis spectrophotometer, attenuated total reflectance-Fourier transform infrared (ATR-FTIR), and aerosol laser time-of-flight mass spectrometer (ALTOFMS) coupled with Fuzzy C-Means (FCM) clustering algorithm, respectively. Experimental results demonstrated that NH 3 has significant promotion effect on benzene SOA formation. Organic ammonium salts, such as ammonium glyoxylate, ammonium 6-oxo-2,4-hexadienoiclate, which are formed from NH 3 reactions with gaseous organic acids were detected as the major particulate NOC products of NH 3 -aged benzene SOA. 1H–imidazole, 1H–imidazole-2-carbaldehyde and other imidazole products via the heterogeneous reactions between NH 3 and dialdehydes of benzene SOA were successfully detected as important brown carbon constituents. The formation of imidazole products suggests that some ambient particles contained organonitrogen compounds may be come from this mechanism. The results of this study may provide valuable information for discussing NH 3 deposition and SOA aging mechanisms.
Print ISSN: 0167-7764
Electronic ISSN: 1573-0662
Topics: Chemistry and Pharmacology , Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 62
Unknown
Springer
Publication Date: 2018-03-06
Description: Based on high-resolution seismic and well datasets, this paper examines the evolution and drowning history of a Paleocene–Eocene carbonate platform in the Offshore Indus Basin of Pakistan. This study uses the internal seismic architecture, well log data as well as the microfauna to reconstruct factors that governed the carbonate platform growth and demise. Carbonates dominated by larger benthic foraminifera assemblages permit constraining the ages of the major evolutionary steps and show that the depositional environment was tropical within oligotrophic conditions. With the aid of seismic stratigraphy, the carbonate platform edifice is resolved into seven seismic units which in turn are grouped into three packages that reflect its evolution from platform initiation, aggradation with escarpment formation and platform drowning. The carbonate factory initiated as mounds and patches on a Cretaceous–Paleocene volcanic complex. Further, the growth history of the platform includes distinct phases of intraplatform progradation, aggradation, backstepping and partial drownings. The youngest succession as late-stage buildup records a shift from benthic to pelagic deposition and marks the final drowning in the Early Eocene. The depositional trend of the platform, controlled by the continuing thermal subsidence associated with the cooling of volcanic margin lithosphere, was the major contributor of the accommodation space which supported the vertical accumulation of shallow water carbonate succession. Other factors such as eustatic changes and changes in the carbonate producers as a response to the Paleogene climatic perturbations played secondary roles in the development and drowning of these buildups.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 63
Unknown
Springer
Publication Date: 2018-03-06
Description: The Middle Miocene Upper Freshwater Molasse sediments represent the last cycle of clastic sedimentation during the evolution of the North Alpine Foreland Basin. They are characterized by small-scale lateral and temporal facies changes that make intra-basin stratigraphic correlations at regional scale difficult. This study provides new U–Pb zircon ages as well as revised 40 Ar/ 39 Ar data of volcanic ash horizons in the Upper Freshwater Molasse sediments from southern Germany and Switzerland. In a first and preliminary attempt, we propose their possible correlation to other European tephra deposits. The U–Pb zircon data of one Swiss (Bischofszell) and seven southern German (Zahling, Hachelstuhl, Laimering, Unterneul, Krumbad, Ponholz) tuff horizons indicate eruption ages between roughly 13.0 and 15.5 Ma. The stratigraphic position of the Unterneul and Laimering tuffs, bracketing the ejecta of the Ries impact (Brockhorizon), suggests that the Ries impact occurred between 14.93 and 15.00 Ma, thus assigning the event to the reversed chron C5Bn1r (15.032–14.870 Ma) which is in accordance with paleomagnetic evidence. We combine our data with published ages of tuff horizons from Italy, Switzerland, Bavaria, Styria, Hungary, and Romania to derive a preliminary tephrochronological scheme for the Middle Miocene in Central Europe in the age window from 13.2 to 15.5 Ma. The scheme is based on the current state of knowledge that the Carpathian–Pannonian volcanic field was the only area in the region producing explosive calc-alkaline felsic volcanism. This preliminary scheme will require verification by more high-quality ages complemented by isotopic, geochemical and paleomagnetic data.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 64
Unknown
Springer
Publication Date: 2018-03-06
Description: The Alborz range in northern Iran stretches along the southern coast of the Caspian Sea and finally runs northeast and merges into the Pamir mountains in Afghanistan. Alborz mountain belt is a doubly vergent orogen formed along the northern edge of the Iranian plateau in response to the closure of the Neo-Tethys ocean and continental collision between Arabia and Eurasia. The south Caspian depression—the Alborz basin of Mesozoic age (with W–E trend) in northern Iran—inverted in response to the Arabia–Eurasia collision. Pre-existing extensional faults of the south Caspian–Alborz system preferentially reactivated as contractional faults because of tectonic inversion. These contractional structures tend to run parallel to the trends of pre-existing extensional faults and acquire W and WNW–ESE orientations across the previous accommodation zones that were imposed by the reactivation of adjacent extensional faults with different directions. The NNE to N dipping faults show evidences of reactivation. The Deylaman fault is one of the important faults of western Alborz in Iran and is an example of inversion tectonic style of deformation in the western Alborz mountain range. The Deylaman fault, with an E–W trend, contains three discontinuous fault segments in the area under investigation. These fault segments have evidence of oblique right-lateral reverse motion and links eastward to the dextral Kandavan thrust. The importance of this fault is due to its effect on sedimentation of several rock units from the Jurassic to Neogene in western Alborz; the rock facies on each side of this fault are very different and illustrate different parts of tectonic history.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 65
Unknown
Springer
Publication Date: 2018-03-06
Description: The Tournaisian–Visean carbonate successions of the Esfahan–Sirjan Basin (ESB) from Sanandaj–Sirjan Zone, Iran, have been used to generate a sequence stratigraphic model that enhances facies characterization and improves paleoenvironmental interpretation of shallow marine successions deposited along the southern margin of the Paleotethys. Detailed facies analysis allowed to differentiate seven facies, which, in order of decreasing abundance, are: (1) shaly and marly, F1; (2) peloidal mudstones/wackestones, F2; (3) peloidal/bioclastic packstones, F3; (4) intraclastic/bioclastic packstones/grainstones, F4; (5) oolitic/bioclastic packstone/grainstone, F5; (6) sandy intraclastic/bioclastic grainstones, F6; (7) sandy oolitic/bioclastic grainstones, F7. The different facies can be grouped into three facies associations that correspond to different environments of a carbonate platform with ramp geometry (homoclinal), from outer ramp (F1 and F2), mid-ramp (F3, F4 and F6) to inner ramp areas (F5 and F7). Meter-scale cycles are the basic building blocks of shallow marine carbonate successions of the Tournaisian–Viséan ramp of the ESB. Small-scale cycles are stacked into medium-scale cycles that in turn are building blocks of large-scale cycles. According to the recognized facies and the stacking pattern of high-frequency cycles across the ramp, five large-scale cycles in the southeastern outcrops (Tournaisian–Viséan) and three large-scale cycles in the northwest outcrops (Viséan) related to eustatic sea-level changes can be recognized. The overall retrogradational nature of the carbonate ramp, illustrated by both vertical facies relationships and the stacking patterns of high-frequency cycles within the third-order cycles, implies that the deposition of the Tournaisian–Viséan successions mainly took place under a long-term transgressive sea-level trend. The stratigraphic architectural style of the sequences, characterized by the lack of lowstand deposits and exposure surfaces, associated with the evidence of progressive increase in the proportion of backstepping of facies belts across bounding surfaces and predominant subtidal characteristics, is in accordance with the long-term transgressive sea-level trend and greenhouse conditions during the Tournaisian–Viséan. The continued transgression on this broad shelfal platform could lead to the shutdown of the shallow water carbonate factory, reduction in sediment supply or sediment transport towards the offshore setting and the development of give-up sequences. The association of transgressive events with the deposition of thick open-marine marls/shales is a common feature in Tournaisian to Viséan times of the southern margin of the Paleotethys.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 66
Unknown
Springer
Publication Date: 2018-03-06
Description: The Agost Basin is characterized by a Miocene–Quaternary shallow marine and continental infilling controlled by the evolution of several curvilinear faults involving salt tectonics derived from Triassic rocks. From the Serravallian on, the area experienced a horizontal maximum compression with a rotation of the maximum stress axis from E–W to N–S. The resulting deformation gave rise to a strike-slip fault whose evolution is characterized progressively by three stages: (1) stepover/releasing bend with a dextral motion of blocks; (2) very close to pure horizontal compression; and (3) restraining bend with a sinistral movement of blocks. In particular, after an incipient fracturing stage, faults generated a pull-apart basin with terraced sidewall fault and graben subzones developed in the context of a dextral stepover during the lower part of late Miocene p.p . The occurrence of Triassic shales and evaporites played a fundamental role in the tectonic evolution of the study area. The salty material flowed along faults during this stage generating salt walls in root zones and salt push-up structures at the surface. During the purely compressive stage (middle part of late Miocene p.p .) the salt walls were squeezed to form extrusive mushroom-like structures. The large amount of clayish and salty material that surfaced was rapidly eroded and deposited into the basin, generating prograding fan clinoforms. The occurrence of shales and evaporites (both in the margins of the basin and in the proper infilling) favored folding of basin deposits, faulting, and the formation of rising blocks. Later, in the last stage (upper part of late Miocene p.p .), the area was affected by sinistral restraining conditions and faults must have bent to their current shape. The progressive folding of the basin and deformation of margins changed the supply points and finally caused the end of deposition and the beginning of the current erosive systems. On the basis of the interdisciplinary results, the Agost Basin can be considered a key case of the interference between salt tectonics and the evolution of strike-slip fault zones. The reconstructed model has been compared with several scaled sandbox analogical models and with some natural pull-apart basins.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 67
Unknown
Springer
Publication Date: 2018-03-06
Description: The ultimate, possibly geodynamic control and potential impact of changes in circulation activity and salt discharge of Mediterranean outflow waters (MOW) on Atlantic meridional overturning circulation have formed long-standing objectives in paleoceanography. Late Pliocene changes in the distal advection of MOW were reconstructed on orbital timescales for northeast Atlantic DSDP/ODP sites 548 and 982 off Brittany and on Rockall Plateau, supplemented by a proximal record from Site U1389 west off Gibraltar, and compared to Western Mediterranean surface and deep-water records of Alboran Sea Site 978. From ~3.43 to 3.3 Ma, MOW temperatures and salinities form a prominent rise by 2–4 °C and ~3 psu, induced by a preceding and coeval rise in sea surface and deep-water salinity and increased summer aridity in the Mediterranean Sea. We speculate that these changes triggered an increased MOW flow and were ultimately induced by a persistent 2.5 °C cooling of Indonesian Through-Flow waters. The temperature drop resulted from the northward drift of Australia that crossed a threshold value near 3.6–3.3 Ma and led to a large-scale cooling of the eastern subtropical Indian Ocean and in turn, to a reduction of African monsoon rains. Vice versa, we show that the distinct rise in Mediterranean salt export after ~3.4 Ma induced a unique long-term rise in the formation of Upper North Atlantic Deep Water, that followed with a phase lag of ~100 ky. In summary, we present evidence for an interhemispheric teleconnection of processes in the Indonesian Gateways, the Mediterranean and Labrador Seas, jointly affecting Pliocene climate.
Print ISSN: 1437-3254
Electronic ISSN: 1437-3262
Topics: Geosciences
Location Call Number Limitation Availability
Others were also interested in ...
• 68
Unknown
Springer
Publication Date: 2018-03-06
Description: The differentiation of blood and menstrual fluid is especially important in cases of alleged sexual assault. While the identification of blood is relatively straightforward, the identification of menstrual fluid in trace evidence has been shown to be more challenging. This may be due to the complex nature of menstrual fluid that leads to intra- and inter-individual differences in composition. Nevertheless, recent advances in DNA methylation profiling have revealed promising markers for the differentiation of the two body fluids and furthermore, markers to distinguish menstrual fluid from vaginal fluid. A literature study was performed and in total, 11 markers were evaluated in this study of which seven could be validated for menstrual fluid and blood identification purposes. Marker “BLU2” (chr16:29757334) was identified as most suitable for differentiation of blood and menstrual fluid.
Electronic ISSN: 1437-1596
Topics: Medicine , Law
Location Call Number Limitation Availability
Others were also interested in ...
• 69
Unknown
Springer
Publication Date: 2018-03-06
Description: The EX27 System is a 6-dye (i.e., FAM, HEX, TAMAR, ROX, VIG, and SIZ-500) kit that combines the 24 autosomal STR loci (i.e., D3S1358, D13S317, D7S820, D16S539, D1S1656, Penta E, TPOX, TH01, D2S1338, CSF1PO, Penta D, D10S1248, D19S433, vWA, D21S11, D18S51, D6S1043, D8S1179, D5S818, D12S391, FGA, D22S1045, D2S441, SE33) with a Y-STR locus (DYS391), an Indel site (YIndel) and Amelogenin, which is designed to amplify DNA from extracts as well as direct amplification from substrates. The new system contains most of the widely used autosomal STR loci around the world and is sensitive to the male component in mixtures and is more accurate in gender determination owing to the DYS391 and YIndel. To demonstrate the suitability for personal identification and parentage testing, the system was validated for sensitivity of detection, species specificity, inhibitor tolerance, DNA mixtures, reproducibility study, and concordance studies based on the SWGDAM developmental validation guidelines. In view of the results, the EX27 System is a robust and reliable amplification kit which can be used for human identification testing.
Electronic ISSN: 1437-1596
Topics: Medicine , Law
Location Call Number Limitation Availability
Others were also interested in ...
• 70
Unknown
Springer
Publication Date: 2018-03-06
Description: Diagnosis of traumatic subarachnoid hemorrhage (SAH), although relatively rare, is important in forensic medicine. It is mostly associated with rupture of the vertebrobasilar artery. Traumatic aneurysm of the intracranial part of the internal carotid artery (ICA) is also rare but has been reported in several studies. It is thought that the intracranial ICA is injured by blunt force to the head, neck, and chest. However, traumatic SAH with fatal acute course resulting from rupture of the ICA is especially uncommon: only two fatal cases without an associated aneurysm have been reported in the English-language literature. Although detecting the arterial lesion is required to make a precise diagnosis, this is sometimes impossible by macroscopic examination at autopsy or by investigation after formalin-fixation according to the position of the lesion. We report a rare case of fatal traumatic SAH associated with intracranial ICA rupture. Postmortem computed tomography angiography was useful to confirm the lesion.
Electronic ISSN: 1437-1596
Topics: Medicine , Law
Location Call Number Limitation Availability
Others were also interested in ...
• 71
Unknown
Springer
Publication Date: 2018-03-06
Description: Diabetic ketoacidosis (DKA) is a metabolic complication of diabetes mellitus that takes a lethal course if untreated. In this way relevant to forensic medicine, secure diagnosis of DKA usually involves the evidence of elevated levels of glucose and the ketone bodies acetone, acetoacetate, and β-hydroxybutyrate in corpse fluids. We conducted a postmortem hydrogen proton magnetic resonance spectroscopy ( 1 H-MRS) in a case of lethal DKA. Distinctive resonances of all three ketone bodies as well as glucose were visible in spectra of cerebrospinal fluid, vitreous humor, and white matter. Estimated concentrations of ketone bodies and glucose supported the findings both of autopsy and biochemical analysis. Advantages of human postmortem 1 H-MRS are the lack of movement and flow artifacts as well as lesser limitations of scan duration. Postmortem 1 H-MRS is able to non-invasively measure concentrations of glucose and ketone bodies in small volumes of various regions of the brain. It may thus become a diagnostic tool for forensic investigations by quick determination of pathological metabolite concentrations in addition to conventional autopsy.
Electronic ISSN: 1437-1596
Topics: Medicine , Law
Location Call Number Limitation Availability
Others were also interested in ...
• 72
Unknown
Springer
Publication Date: 2018-03-06
Description: Three-dimensional (3D) measurement techniques are gaining importance in many areas. The latest developments brought more cost-effective, user-friendly, and faster technologies onto the market. Which 3D techniques are suitable in the field of forensic medicine and what are their advantages and disadvantages? This wide-ranging study evaluated and validated various 3D measurement techniques for the forensic requirements. High-tech methods as well as low-budget systems have been tested and compared in terms of accuracy, ease of use, expenditure of time, mobility, cost, necessary knowhow, and their limitations. Within this study, various commercial measuring systems of the different techniques were tested. Based on the first results, one measuring system was selected for each technique, which appeared to be the most suitable for the forensic application or is already established in forensic medicine. A body of a deceased, a face and an injury of a living person, and a shoe sole were recorded by 11 people with different professions and previous knowledge using the selected systems. The results were assessed and the personal experiences were evaluated using a questionnaire. In addition, precision investigations were carried out using test objects. The study shows that the hand-held scanner and photogrammetry are very suitable for the 3D documentation of forensic medical findings. Their moderate acquisition costs and easy operation could lead to more frequent application in forensic medicine in the future. For special applications, the stripe-light scanner still has its justification due to its high precision, the flexible application area, and the high reliability. The results show that, thanks to the technological advances, the 3D measurement technology will have more and more impact on the routine of the forensic medical examination.
Electronic ISSN: 1437-1596
Topics: Medicine , Law
Location Call Number Limitation Availability
Others were also interested in ...
• 73
Unknown
Springer
Publication Date: 2018-03-06
Description: The purpose of the present research is to study the radiographic visibility of the periodontal ligament in third molars from a northern Chinese population to determine if this methodology could be used for the 18-year threshold. A total of 1300 conventional orthopantomograms from 650 males and 650 females of northern Chinese subjects aged between 15 and 40 years were analyzed. The radiographic visibility of the periodontal membrane of fully mineralized third molars was assessed using the stages described by Olze et al. (2010). Stage 0 first appeared at the age of 17.05 years in males and at the age of 18.76 years in females. Stage 1 was first detected at 18.52 years in males and 19.59 years in females. Stage 2 was first achieved by males at the age of 22.33 years and by females at the age of 21.37 years. The earliest appearance of stage 3 was 26.85 years in males and 24.92 years in females. If stage 1 is determined, it is possible to prove that an individual has already attained the age of 18 years. Stages 2 and 3 can be used to determine that a person is over 21 years of age. However, it should also be noted that in 271 cases of tooth 38 and 255 cases of tooth 48, the visibility stage could not be reliably assessed because of fused roots or narrowed furcations. Therefore, this method seems to be of limited value for age estimation in the Chinese population.
Electronic ISSN: 1437-1596
Topics: Medicine , Law
Location Call Number Limitation Availability
Others were also interested in ...
• 74
Unknown
Springer
Publication Date: 2018-03-06
Description: Decomposition of the human body and human face is influenced, among other things, by environmental conditions. The early decomposition changes that modify the appearance of the face may hamper the recognition and identification of the deceased. Quantitative assessment of those changes may provide important information for forensic identification. This report presents a pilot 3D quantitative approach of tracking early decomposition changes of a single cadaver in controlled environmental conditions by summarizing the change with weekly morphological descriptions. The root mean square (RMS) value was used to evaluate the changes of the face after death. The results showed a high correlation ( r  = 0.863) between the measured RMS and the time since death. RMS values of each scan are presented, as well as the average weekly RMS values. The quantification of decomposition changes could improve the accuracy of antemortem facial approximation and potentially could allow the direct comparisons of antemortem and postmortem 3D scans.
Electronic ISSN: 1437-1596
Topics: Medicine , Law
Location Call Number Limitation Availability
Others were also interested in ...
• 75
Unknown
Springer
Publication Date: 2018-03-06
Print ISSN: 0948-3349
Electronic ISSN: 1614-7502
Topics: Energy, Environment Protection, Nuclear Power Engineering , Economics
Location Call Number Limitation Availability
Others were also interested in ...
• 76
Unknown
Springer
Publication Date: 2018-03-06
Description: Age estimation based on aspartic acid racemization (AAR) in dentine is one of the most precise methods in adult age. Caries induces protein degradation and may have an impact on the kinetics of AAR in dentine. We systematically examined standardized prepared dentine samples from caries-affected teeth to clarify the question, if caries-affected teeth should not be used for age estimation based on AAR at all, or if the analysis of dentine samples from such teeth may be useful after removal of the caries-affected tissue according to clinical standards. Our results suggest that caries may lead to an extensive protein degradation even in macroscopically healthy-appearing dentine samples from caries-affected teeth and may significantly affect the precision of age estimation. To ensure the quality of age estimation based on AAR in forensic practice, we recommend using dentine samples from healthy teeth. If only caries-affected teeth are available, dentine samples from at least two teeth from the same individual should be analyzed as it seems unlikely that caries-induced protein degradation occurred with identical kinetics in two different teeth. In any case, results of the analysis of caries-affected teeth must be interpreted with caution.
Electronic ISSN: 1437-1596
Topics: Medicine , Law
Location Call Number Limitation Availability
Others were also interested in ...
• 77
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose The article aims to test indicators for assessing the environmental and social impacts of biorefineries. Testing environmental and social impact categories and indicators, and selecting the most suitable ones, will simultaneously contribute to the further development of social life cycle assessment (S-LCA) methodologies while assessing several dimensions of sustainability at biorefineries. Methods The work applies two methodologies, environmental LCA (E-LCA) and social LCA (S-LCA), to two hypothetical production processes of second-generation bioethanol and biochemical in two alternative locations (Norway and the USA). Five impact categories were chosen for the E-LCA. The S-LCA was performed in two stages: a generic assessment (top-down approach) using the social hotspot database (SHDB 2013 ) to screen for potential social issues in the stakeholder group Worker in Norway and the USA and a specific assessment (bottom-up approach) for collecting data and confirming or refuting the SHDB results in the Norwegian case only. Results and discussion Bioethanol produced in the Norwegian biorefinery would perform relatively well in relation to climate change targets, with emissions of approximately 11 g CO 2 -eq/MJ. The same production process located in the USA would produce emissions of approximately 29 g CO 2 -eq/MJ. Other biorefinery products are difficult to compare because of a lack of clear alternatives. Bioethanol and biochemicals produced in the hypothetical USA production process have higher burdens than those from the Norwegian production process in all environmental categories assessed. For both production processes, the main social risks were in the category Health and safety followed by Labor rights and decent work . More detailed investigations in an existing Norwegian biorefinery value chain confirmed some of the risk issues but discarded others, demonstrating the necessity of providing specific data and results for the social dimension. Conclusions E-LCA and S-LCA make it possible to highlight the main environmental and social challenges when producing biochemicals. The SHDB has potential as a social screening tool although social indicators are not yet well established. Hence, specific assessment is necessary for validating the results in the social dimension. S-LCA is still in its infancy and needs to be applied in order to develop the best practice. The two methodologies addressed bioethanol and biochemical production performance in two different dimensions (environmental and social), and their combination makes it possible to achieve results that integrate the product-oriented approach with the more location-specific approach.
Print ISSN: 0948-3349
Electronic ISSN: 1614-7502
Topics: Energy, Environment Protection, Nuclear Power Engineering , Economics
Location Call Number Limitation Availability
Others were also interested in ...
• 78
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose The purpose of this paper was to assess the impact of survivorship care plan (SCP) provision and moderating factors on health care use following endometrial cancer treatment. Methods Women newly diagnosed with endometrial cancer were included in a pragmatic cluster randomized trial at 12 hospitals in the Netherlands and were randomly assigned to SCP or usual care ( n  = 221; 75% response). The SCP was generated using the web-based Registrationsystem Oncological GYnecology (ROGY) and provided tailored information regarding disease, treatment, and possible late-effects. Cancer-related use of general practitioner, specialist, and additional health care was collected through questionnaires after diagnosis and at 6-, 12-, and 24-month follow-up and compared using linear multilevel regression analyses. Results Women who received an SCP had more cancer-related primary care visits compared to the usual care arm during the first year after diagnosis (β = 0.7, p  〈 0.01). At 6-month follow-up, women in the SCP group used more additional health care compared to women receiving usual care (24 vs. 11%, p  = 0.04). Women with anxious symptoms ( p  = 0.03) and women who received radiotherapy ( p  = 0.01) had a higher primary care use within the first year after treatment, when receiving an SCP. Conclusions The SCP increases primary health care consumption the first year after treatment, particularly in women treated with radiotherapy and women with anxious symptoms. Implications for cancer survivors These findings imply that the SCP enables women in need of supportive care to seek relevant care at an early stage after treatment. Whether this results in improved patient-reported outcomes in the long-term needs to be further studied.
Print ISSN: 1932-2259
Electronic ISSN: 1932-2267
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 79
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose We examined the degree of over- and under-reporting of cardiovascular diseases (CVDs) among female breast cancer survivors comparing self-reports to diagnostic codes from the Danish National Patient Register (NPR). Methods The study comprised 357 Danish breast cancer patients from the WECARE study who completed a telephone interview concerning CVDs. Disease diagnoses for these women were obtained from the NPR. Agreement was calculated as the number of diagnoses that were both self-reported and in the NPR divided by (1) number of self-reported diagnoses (over-reporting) or (2) number of diagnoses in the NPR (under-reporting). Results In total, 68 women reported 96 specific cardiovascular outcomes of which 56 (58%) were found in the NPR. Ninety cardiovascular diagnoses were found in the NPR of which 56 (62%) were specifically reported at the interview. There was 80% agreement as to the occurrence of a cardiovascular diagnosis overall. Of 289 women reporting no CVD, 273 (94%) had no diagnoses in the NPR. Conclusions Breast cancer survivors seem to report absence of CVD accurately, but they both over-report and under-report specific cardiovascular diagnoses. Using a broader definition of CVDs improves the agreement between self-reported and NPR data. Implications for cancer survivors Determining how cancer treatments affect the risk of cardiovascular morbidities is essential, and the development of high-quality methods for collecting such data is critical. While self-reported data are adequate for assessing the presence of any CVD condition, medical record review will yield higher quality data on specific CVD conditions.
Print ISSN: 1932-2259
Electronic ISSN: 1932-2267
Topics: Medicine
Location Call Number Limitation Availability
Others were also interested in ...
• 80
Unknown
Springer
Publication Date: 2018-03-06
Description: Purpose With increasing cancer care costs and greater patient cost-sharing in the USA, understanding access to medical care among cancer survivors is imperative. This study aims to identify financial, psychosocial, and cancer-related barriers to the receipt of medical care, tests, or treatments deemed necessary by the doctor or patient for cancer among cancer survivors age 〈 65 years. Methods We used data on 4321 cancer survivors aged 18–64 years who completed the 2012 LIVESTRONG Survey. Multivariable logistic regression was used to identify risk factors associated with the receipt of necessary medical care, including sociodemographic, financial hardship, debt amount, caregiver status, and cancer-related variables. Results Approximately 28% of cancer survivors were within 1 year, and 43% between 1 and 5 years, since their last treatment at the time of survey. Nearly 9% of cancer survivors reported not receiving necessary medical care. Compared to survivors without financial hardship, the likelihood of not receiving necessary medical care significantly increased as the amount of debt increased among those with financial hardship (RR Financial hardship w/〈 $10,000 debt = 1.94, 95% CI 1.55–2.42, and RR RR Financial hardship w/≥$10,000 debt  = 3.41, 95% CI 2.69–4.33, p  〈 0.001). Survivors who reported lack of a caregiver, being uninsured, and not receiving help understanding medical bills were significantly more likely to not receive necessary medical care. Conclusion We identified key financial and insurance risk factors that may serve as significant barriers to the receipt of necessary medical care among cancer survivors age 〈 65 in the USA Implications for cancer survivors The majority of cancer survivors reported receiving medical care either they or their doctors deemed necessary. However, identifying potentially modifiable barriers to receipt of necessary medical cancer care among cancer survivors age 〈 65 is imperative for developing interventions to ensure equitable access to care and reducing cancer disparities.
Print ISSN: 1932-2259
Electronic ISSN: 1932-2267
Topics: Medicine