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  (2,354,651)
Collection
Language
Years
  • 1
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Print ISSN: 0949-1775
    Electronic ISSN: 1432-0517
    Topics: Chemistry and Pharmacology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The production of reference materials (RMs) is a key activity for the improvement and maintenance of a worldwide coherent measurement system. General requirements for all types of RM production are set out in ISO 17034. These general requirements include the assessment of homogeneity and stability. Technical detail is, however, left entirely to other guides, of which ISO Guide 35 is the most general and comprehensive. This paper provides an overview of the provisions for stability and homogeneity assessment in ISO Guide 35:2017, with particular attention to changes from the 2006 edition. Important changes include new guidance on the need for experimental studies when substantial prior experience is available; a larger range of homogeneity study designs; improved guidance on the use of accelerated stability studies; additional, and more flexible, guidance on within-unit homogeneity assessment; greater attention to post-certification monitoring; and new provisions for end-user storage and repeated sampling from individual RM units.
    Print ISSN: 0949-1775
    Electronic ISSN: 1432-0517
    Topics: Chemistry and Pharmacology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Marine sediment certified reference material (CRM), IAEA-456 was recently produced by the Environment Laboratories of the International Atomic Energy Agency (IAEA) and certified for trace elements and methyl mercury (CH 3 Hg). This paper presents the sample preparation methodology, material homogeneity and stability studies, evaluation of results from the characterisation campaign, the assignment of property values and their associated uncertainty. The reference values and associated expanded uncertainty for nine trace elements (Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn) and CH 3 Hg in marine sediment sample are established. The new CRM can be used for the development and validation of analytical methods, for the determination of trace elements and methyl mercury in sediments and also for quality assurance/quality control purposes.
    Print ISSN: 0949-1775
    Electronic ISSN: 1432-0517
    Topics: Chemistry and Pharmacology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: A quality control material for inorganic constituents present in a phosphate-bearing rock used to manufacture phosphate fertilizers was produced and characterized according to the ISO Guide 80. The evaluation of the estimated minimum mass, homogeneity, and stability of the material was performed using microwave-assisted digestion and inductively coupled plasma optical emission spectrometry (ICP-OES) as an in-house validated technique for determination of Al, As, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, V, and Zn. Phosphorus mass fraction determination was done by laser-induced breakdown spectroscopy. The accuracy of the measurement results was confirmed by analyzing the certified phosphate rock and fertilizer certified reference materials according to NIST SRM 694 and SRM 695. One-way analysis of variance (ANOVA) was applied to the measurement data, and the homogeneity and stability of the material presented averages within the 95 % confidence interval. The results from the preparation and with collaborative trial allowed the calculation and estimation of the consensus value and its expanded measurement uncertainties, obtained by combining the uncertainty contributions from characterization ( u char ), between-bottle homogeneity ( u bb ), short-term stability ( u sts ), and long-term stability ( u lts ) for each evaluated analyte mass fraction.
    Print ISSN: 0949-1775
    Electronic ISSN: 1432-0517
    Topics: Chemistry and Pharmacology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Accreditation of calibration laboratories is a means for achieving competence recognition and assuring customers that their calibration services are accurate and reliable. Moreover, it is a powerful tool for a National Metrology Institute (NMI), enabling the formal acceptance of its measurement results. It could be especially useful when calibration activities are performed in well-developed laboratories, which have participated successfully in interlaboratory comparisons but have been awaiting the publication of Calibration and Measurement Capabilities in the BIPM Key comparison database. This paper describes establishment and implementation of a quality management system in the NMI of Montenegro called Bureau of Metrology (MBM) that complies with ISO/IEC 17025. We have presented the results of the first audit evaluation, corrective actions, preparation of quality management documentation, measurement traceability, as well as advantages of being accredited. Our experience of implementing ISO/IEC 17025 for the accreditation of national calibration laboratories established within the MBM shows that strategic planning, establishment of long-term objectives, as well as the commitment to fulfilling standard requirements are the basis for acceptable calibration results. International acceptance of confidence and reliability of calibration services and measurement results provided by the MBM laboratories represents a useful marketing tool for promoting the image of the institution.
    Print ISSN: 0949-1775
    Electronic ISSN: 1432-0517
    Topics: Chemistry and Pharmacology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Uncertainty in measurement is very important in the process of conformity assessment. As it is generally declared, based on the measured value of a property of an item, there is always the risk of incorrect decisions, which are of two types: an item accepted as “conforming” may actually be “non-conforming”, and an item rejected as “non-conforming” may actually be “conforming”. In order to reduce the risks associated with decision-making, it is required to reduce the measurement uncertainty to an acceptable level termed as “target uncertainty”. In order to reduce the uncertainty of a particular measurement, it would be necessary to focus on decreasing the uncertainties arising from the relevant components. There are always different solutions to reduce the uncertainties arising from each inclusive component. Each of these solutions imposes a different cost on the measurement system. Therefore, a solution should be selected, among several possible alternatives, to reduce the uncertainties arising from each relevant component and to impose the lowest cost to the measurement system to “target uncertainty”. Accordingly, in this paper through a case study, a model is presented that can reduce uncertainty with the lowest possible cost to the optimally needed level using a mathematical optimization technique. The mathematical model presented in this paper can be used in measurement uncertainty optimization in many laboratories, which require a reduction in uncertainty and the risks associated with decision-making based on measurement results. Furthermore, the use of the proposed model will help to reduce the unnecessary costs of analysis in different laboratory centers.
    Print ISSN: 0949-1775
    Electronic ISSN: 1432-0517
    Topics: Chemistry and Pharmacology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Sum parameters (otherwise known as composite parameters) describe similar chemical, physicochemical or biological characteristics of different substances, substance groups or mixtures of substances. These might contain the same chemical element. Such parameters are total organic carbon or total bound nitrogen. Chemical oxygen demand is a shared chemical characteristic—the oxidizability of constituents by dichromate. The focus of the paper is on the uncertainty estimation of the determination of chemical sum parameters in water samples from method validation derived data—total organic carbon, chemical oxygen demand, biochemical oxygen demand, total bound nitrogen and total suspended solids. The results for the measurement uncertainty estimations according to ISO 21748 and ISO 11352, as only applicable to the field of water analysis, are presented and compared. Based on the results obtained and the experimental design, the use of ISO 11352 for the measurement uncertainty estimation is recommended. This international standard employs fewer determinations (a minimum number of eight measurements are required, compared to fifteen), fewer working days (one compared to five) and easier measurement uncertainty components’ calculations and even gives opportunity for routine laboratories to use standard solutions over the more expensive certified reference materials for the measurement uncertainty estimation during the method validation in water analysis.
    Print ISSN: 0949-1775
    Electronic ISSN: 1432-0517
    Topics: Chemistry and Pharmacology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Purpose The detection rate and the metabolic behavior of 18F-FDG-PET/CT in splenic marginal zone lymphoma (SMZL) are not yet clear. Our aim was to investigate the metabolic behavior of SMZL and whether the tumor stage (acc. Ann Arbor) epidemiological (age, gender), histological (Ki-67 index, plasmacytic differentiation), and morphological (splenic diameter maximum) features might be related to 18F-FDG PET/CT results. Methods Fifty-one patients (34 male, 17 female; average age 70 years) with histologically confirmed SMZL who underwent a 18F-FDG PET/CT for initial staging were included: PET/CT images were analyzed visually and semi-quantitatively (SUVmax, lesion-to-liver SUVmax ratio, and lesion-to-blood pool SUVmax ratio). Splenic uptake was divided as diffuse or focal. Results Thirty-nine patients (76%) had FDG-avid SMZL (7 with focal splenic lesions and 32 with diffuse splenic uptake), while the remaining 12 had no increased splenic uptake. Among patients with FDG-avid lesions, average SUVmax was 4.3, lesion-to-liver SUVmax ratio 2.3, and lesion-to-blood pool SUVmax ratio 3. 18F-FDG avidity was significantly associated with Ki-67 index and not correlated with other features. Semiquantitative PET/CT parameters (SUVmax, lesion-to-liver SUVmax ratio, and lesion-to-blood pool SUVmax ratio) did not correlate significantly with any variable. Progression-free survival time was not influenced by FDG avidity of SMZL. Conclusions 18F-FDG avidity was noted in 76% of SMZL with diffuse splenic uptake as main pattern of presentation and is correlated with Ki-67 score only.
    Electronic ISSN: 1432-0509
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Purpose The purpose of the study was to retrospectively analyze whether double-echo gradient-echo (GRE) chemical shift imaging (CSI) can differentiate between pancreatic metastases from clear cell renal cell carcinoma (PM-ccRCC) and pancreatic neuroendocrine tumor (pNET). Methods Institutional review board approval and informed consent were waived. CSI, T2WI, DWI, and DCE magnetic resonance imaging (MRI) were performed in patients with PM-ccRCC and pNET. Eleven patients with PM-ccRCC and 24 patients with pNET were enrolled into this retrospective study. The signal intensity was measured in the pancreatic tumor and spleen on in-phase and opposed-phase images. The signal intensity index (SII) and tumor-to-spleen ratio (TSR) in PM-ccRCC and pNET were calculated and compared. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic accuracy of SII and TSR in the differentiation between PM-ccRCC and pNET. Results The SII between PM-ccRCC and pNET (20.3% ± 16.8% vs. − 3.2% ± 11.4%) was significantly different ( P  〈 0.001), as was the TSR (− 19.2% ± 16.6% vs. 6.0% ± 13.8%) ( P  〈 0.001). The area under the ROC curve was 0.917 for the SII and 0.902 for the TSR. Additionally, an SII threshold value of 8.1% permitted the differentiation of PM-ccRCC from pNET with a sensitivity of 90.9%, a specificity of 91.7%, a positive predictive value of 90.1%, a negative predictive value of 91.7%, and an accuracy of 91.4%. A TSR cut-off value of − 4.7% enabled the differentiation of the two groups with a sensitivity of 79.2%, a specificity of 90.9%, a positive predictive value of 90.9%, a negative predictive value of 79.2% and an accuracy of 82.9%. Conclusion Double-echo GRE chemical shift MR imaging can accurately differentiate between PM-ccRCC and pNET.
    Electronic ISSN: 1432-0509
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Purpose The purpose of this study is to assess the heterogeneity of tumor enhancement using fractal analysis on contrast-enhanced computed tomography (CE-CT) for predicting malignant potential of gastrointestinal stromal tumor (GIST). Methods We retrospectively identified 64 patients (36 M/28 W; median age: 65) with GISTs who received CE-CT and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) followed by curative surgery. Fractal analysis was applied to CE-CT image, and fractal dimension (FD) was measured. Diagnostic value of FD for malignant potential of GIST was compared with that of FDG-PET using the risk classification and Ki67 index. Results 14 patients were categorized as the high risk, and 50 patients were as the very low, low or intermediate risk. FD of high-risk group was significantly higher than that of the other-risk group ( p  〈 0.05). The areas under the ROC curves of FD and SUV max for prediction of high-risk group were 0.82 and 0.93 (accuracy: 84.4% and 98.5%). FD showed a significant positive correlation with Ki67 index ( p  = 0.01). Conclusion Diagnostic value of CT fractal analysis for prediction of high-risk GIST is comparable with FDG-PET. In terms of cost and availability, fractal analysis has a potential to be an optimal preoperative biomarker.
    Electronic ISSN: 1432-0509
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 11
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Objective The purpose of this study was to compare the sensitivity and specificity of diffusion-weighted liver MRI alone with complete, multiphasic gadoteridol-enhanced MRI for the detection of hepatocellular carcinoma in cirrhotic patients before liver transplant. Materials and methods This single institution retrospective study was performed after IRB approval and was HIPAA compliant. MRI scans of 37 patients who underwent liver transplant were evaluated and findings correlated with liver explant (36) or biopsy (1). All MRI scans were obtained within six months of explant. MRI from 17 patients with liver lesions by report at imaging subsequently proven to be HCC at pathology and 20 controls without liver lesions by imaging and pathology were reviewed in random order on the radiology PACS by three independent readers blinded to the MRI reports and pathology reports in two separate sittings. First, only the diffusion-weighted images (DWI) were interpreted. Second, the complete multiphasic MRI exam with DWI was reviewed. A consensus read was obtained by two separate radiologists who had access to the patients’ explant data in order to map lesions. Reader-specific and pooled classification was assessed using sensitivity, specificity, positive predictive value, and negative predictive values and corresponding 95% confidence intervals (CI) for both DWI and complete MRI examination readings compared to pathology. McNemar’s test and Kappa coefficient were used to assess differences (agreement) in DWI and complete examination readings. Results A total of 37 patients have been studied (25M 12F age range 21–70). Averaged results of the three independent readers demonstrated a sensitivity of 78% (95% CI 65–89%) and specificity of 88% (95% CI 77–95%) for DWI alone for detection of liver lesions, with a positive predictive value of 85% (95% CI 72–94%) and a negative predictive value of 83% (95% CI 71–91%). Review of the complete MRI exam showed a sensitivity of 90% (95% CI 76–97%) and a specificity of 82% (95% CI 66–92%) with a positive predictive value of 83% (95% CI 69–93%) and a negative predictive value of 89% (95% CI 74–97%). McNemar’s agreement test revealed no significant difference between the DWI and complete multiphasic interpretations ( p  = 0.3458), with simple Kappa coefficient of 0.6716 (95% CI 0.5332–0.8110). Lesions identified on DWI ranged in size from 1.5 to 5 cm. Detection of lesions was decreased in the presence of artifact from motion, large ascites, and technical issues. Conclusion Diffusion-weighted MRI has NPV and PPV comparable to complete multiphasic MRI examination for liver lesion detection in cirrhotic patients and may have a role in screening.
    Electronic ISSN: 1432-0509
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 12
    facet.materialart.
    Unknown
    Springer
    In: 4OR
    Publication Date: 2018-03-05
    Print ISSN: 1619-4500
    Electronic ISSN: 1614-2411
    Topics: Mathematics
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 13
    facet.materialart.
    Unknown
    Springer
    In: 4OR
    Publication Date: 2018-03-05
    Print ISSN: 1619-4500
    Electronic ISSN: 1614-2411
    Topics: Mathematics
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 14
    facet.materialart.
    Unknown
    Springer
    In: 4OR
    Publication Date: 2018-03-05
    Description: This is the traditional triennial note used by the editors to give the readers of 4OR information on the state of the journal and its future. In the 3 years that have passed since the last editorial note (Liberti et al. in Q J Oper 13:1–13, 2015 ), three volumes (each containing four issues) of the journal have been published: vol. 13 (2015), vol. 14 (2016), and vol. 15 (2017).
    Print ISSN: 1619-4500
    Electronic ISSN: 1614-2411
    Topics: Mathematics
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 15
    facet.materialart.
    Unknown
    Springer
    In: 4OR
    Publication Date: 2018-03-05
    Description: In this paper, we study a vector scheduling problem with rejection on a single machine, in which each job is characterized by a d -dimension vector and a penalty, in the sense that, jobs can be either rejected by paying a certain penalty or assigned to the machine. The objective is to minimize the sum of the maximum load over all dimensions of the total vector of all accepted jobs, and the total penalty of rejected jobs. We prove that the problem is NP-hard and design two approximation algorithms running in polynomial time. When d is a fixed constant, we present a fully polynomial time approximation scheme.
    Print ISSN: 1619-4500
    Electronic ISSN: 1614-2411
    Topics: Mathematics
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 16
    facet.materialart.
    Unknown
    Springer
    In: 4OR
    Publication Date: 2018-03-05
    Description: In this paper we analyze an inter-temporal optimization problem of a representative firm that invests in horizontal and vertical innovations and that faces a constraint with respect to total R&D spending. We find that there can exist two different steady-states of the economy when the amount of research spending falls short of an endogenously determined threshold: one with higher productivities and less new technologies being developed, and the other with more technologies being created and lower productivities. But, for a higher amount of R&D spending the steady-state becomes unique and the firm produces the whole spectrum of available technologies. Thus, a lock-in effect may arise that, however, can be overcome by raising R&D spending sufficiently.
    Print ISSN: 1619-4500
    Electronic ISSN: 1614-2411
    Topics: Mathematics
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 17
    facet.materialart.
    Unknown
    Springer
    In: 4OR
    Publication Date: 2018-03-05
    Print ISSN: 1619-4500
    Electronic ISSN: 1614-2411
    Topics: Mathematics
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 18
    facet.materialart.
    Unknown
    Springer
    In: 4OR
    Publication Date: 2018-03-05
    Print ISSN: 1619-4500
    Electronic ISSN: 1614-2411
    Topics: Mathematics
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 19
    facet.materialart.
    Unknown
    Springer
    In: 4OR
    Publication Date: 2018-03-05
    Description: This paper investigates the coordination problem of a supply chain (SC) composed of a manufacturer exhibiting corporate social responsibility (CSR) and a retailer faced with random demand. The random demand is made up of the multiplication of price-dependent demand and random demand factor (RDF), plus the CSR-dependent demand. The centralized decision problem of the SC is an extension of the existing price setting newsvendor problem (PSNP). It is found that the sufficient condition for the quasi-concavity of expected profit (EP) on PSNP can not ensure the quasi-concavity of EP of the SC. Then, the concavity condition of EP related to the CSR effect factor is presented in the case of uniformly distributed RDF and linear demand in price, and the concavity of EP is proven under centralized decision. For decentralized decision under manufacturer’s Stackelberg game, the manufacturer determines wholesale price and its CSR investment, and then the retailer decides the order quantity and the retail price. The standard revenue-sharing (RS) contract is found not able to coordinate the SC, so a modified RS (MRS) contract is proposed to coordinate the SC. Finally, numerical examples illustrate the validity of the theoretical analysis and the coordination effectiveness of the MRS contract via Matlab.
    Print ISSN: 1619-4500
    Electronic ISSN: 1614-2411
    Topics: Mathematics
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 20
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background Full recovery is unlikely for severe cubital tunnel syndrome, and prognostic factors remain uncertain. We aimed to identify predictors of surgical outcome for these patients. Methods One hundred forty-six patients with McGowan grade III cubital tunnel syndrome were evaluated retrospectively with a minimum follow-up of 2 years. All patients underwent either in situ decompression or subcutaneous transposition. The primary outcome measure was postoperative McGowan grade. Predictors included age, sex, dominant hand, disease duration, diabetes mellitus, smoking, alcohol, surgical procedure, follow-up time and preoperative electrophysiological data. Spearman’s rank correlation and ordinal logistic regression model were used to assess the effect of independent variables on the postoperative McGowan grade. Results At the last follow-up, improvement by at least one McGowan grade was reached in 118 cases (80.8%), and complete recovery was achieved in 40 hands (27.4%), while 28 extremities (19.2%) remained at grade III. Older age [per 10-year increase, odds ratio (OR) 2.10; 95% confidence interval (95% CI) 1.55–2.84, p  〈 0.001], longer disease duration (per 1-year increase, OR 1.31; 95% CI 1.16–1.49, p  〈 0.001), absent sensory nerve conduction (OR 2.55; 95% CI 1.25–5.21, p  = 0.010) and shorter postoperative follow-up (per 1-year increase, OR 0.76; 95% CI 0.65–0.90, p  = 0.001) were associated with a higher postoperative McGowan grade. Conclusion Significant improvement but not complete recovery could be expected following in situ decompression or subcutaneous transposition for severe cubital tunnel syndrome. Older age, longer disease duration, absent sensory nerve conduction and shorter postoperative follow-up are independent predictors of worse outcomes.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 21
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background Perineural spread (PNS) of pelvic cancer along the lumbosacral plexus is an emerging explanation for neoplastic lumbosacral plexopathy (nLSP) and an underestimated source of patient morbidity and mortality. Despite the increased incidence of PNS, these patients are often times a clinical conundrum—to diagnose and to treat. Building on previous results in modeling glioblastoma multiforme (GBM), we present a mathematical model for predicting the course and extent of the PNS of recurrent tumors. Methods We created three-dimensional models of perineurally spreading tumor along the lumbosacral plexus from consecutive magnetic resonance imaging scans of two patients (one each with prostate cancer and cervical cancer). We adapted and applied a previously reported mathematical model of GBM to progression of tumor growth along the nerves on an anatomical model obtained from a healthy subject. Results We were able to successfully model and visualize perineurally spreading pelvic cancer in two patients; average growth rates were 60.7 mm/year for subject 1 and 129 mm/year for subject 2. The model correlated well with extent of PNS on MRI scans at given time points. Conclusions This is the first attempt to model perineural tumor spread and we believe that it provides a glimpse into the future of disease progression monitoring. Every tumor and every patient are different, and the possibility to report treatment response using a unified scale—as “days gained”—will be a necessity in the era of individualized medicine. We hope our work will serve as a springboard for future connections between mathematics and medicine.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 22
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background Wound healing impairment is a serious problem in surgical disciplines which may be associated with chronic morbidity, increased cost and patient discomfort. Here we aimed to investigate the relevance of bacterial colonisation on suture material using polymerase chain reaction (PCR) to detect and taxonomically classify bacterial DNA in patients with and without wound healing problems after routine neurosurgical procedures. Methods Repeat surgery was performed in 25 patients with wound healing impairment and in 38 patients with well-healed wounds. To determine the presence of bacteria, a 16S rDNA-based PCR detection method was applied. Fragments of 500 bp were amplified using universal primers which target hypervariable regions within the bacterial 16S rRNA gene. Amplicons were separated from each other by single-strand conformation polymorphism (SSCP) analysis, and finally classified using Sanger sequencing. Results PCR/SSCP detected DNA of various bacteria species on suture material in 10/38 patients with well-healed wounds and in 12/25 patients with wound healing impairment including Staphylococcus aureus , Staphylococcus epidermidis , Propionibacterium acnes and Escherichia coli . Microbiological cultures showed bacterial growth in almost all patients with wound healing impairment and positive results in PCR/SSCP (10/12), while this was the case in only one patient with a well-healed wound (1/10). Conclusions Colonisation of suture material with bacteria occurs in a relevant portion of patients with and without wound healing impairment after routine neurosurgical procedures. Suture material may provide a nidus for bacteria and subsequent biofilm formation. Most likely, however, such colonisation of sutures is not a general primer for subsequent wound infection.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 23
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background The aim of this study was to develop a minimal invasive complete spinal cord injury (SCI) minipig model for future research applications. The minipig is considered a translationally relevant model for SCI research. However, a standardized minimal invasive complete SCI model for pigs has not yet been established. Methods Adult Göttingen minipigs were anesthetized and placed in extended prone position. After initial computed tomography (CT) scan, the skin was incised, a needle placed in the epidural fatty tissue. Using the Seldinger technique, a guidewire and dilators were introduced to insert the balloon catheter to Th12. After confirmation of the level Th11/Th12, the balloon was inflated to 2 atm for 30 min. The severity of the lesion was followed by CT and by MRI, and by immunohistochemistry. Function was assessed at the motor and sensory level. Results Duration of procedure was about 60 min including the 30-min compression time. The balloon pressure of 2 atm was maintained without losses. The lesion site was clearly discernible and no intradural bleeding was observed by CT. Neurological assessments during the 4-month follow-up time showed consistent, predictable, and stable neurological deficits. Magnetic resonance imaging analyses at 6 h and 4 weeks post SCI with final immunohistochemical analyses of spinal cord tissue underlined the neurological outcomes and proved SCI completeness. Conclusions We have established a new, minimal invasive, highly standardized, CT-guided spinal cord injury procedure for minipigs. All risks of the open surgery can be excluded using this technique. This CT-guided SC compression is an excellent technique as it avoids long surgery and extensive trauma and allows a feasible inter-animal comparison.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 24
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background Overall (OS) and progression-free survival (PFS) of patients undergoing spinal ependymoma resection has been frequently reported. Contrarily, OS and PFS of purely intramedullary ependymomas have not been clearly determined yet. Methods The data of 37 patients undergoing resection of an intramedullary ependymoma (IE) from January 2000 to December 2016 were analysed retrospectively. Results The mean age was 46 years. The male:female ratio was 24:13. The median duration of symptoms was 12 months. Sixty-two per cent of ependymomas were in the cervical, 24% in the thoracic, and 14% in the conus region in our series. The median volume was 1.3 ml. A syrinx was found in 49% and a cyst in 32%. GTR was achieved in 89%, STR in three (8%), and PR in one patient (3%). Median follow-up was 114 months. PFS was 87%, 82%, and 82% at 5, 10, and 15 years, respectively. OS was 97%, 88%, and 63% at 5, 10, and 15 years, respectively. There was a significant difference in PFS depending on the extent of resection and in OS depending on the pre-operative clinical status. There was no significant difference in OS and PFS regarding the other examined influencing factors. Conclusion GTR resection was the most important factor influencing PFS. According to our results OS of IEs is much worse than that of spinal ependymomas. Our analysis confirms that patients with good pre-operative (McCormick grade 1 and 2) clinical status have significantly better OS than patients with McCormick grade 3 and higher.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 25
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background Mycotic aneurysms, although well recognized, are relatively rare intracranial vascular pathology. These aneurysms are typically located in distal cortical vessels. When these aneurysms are located in eloquent cerebral territories, they may become challenging to treat. Eloquent location may necessitate intraoperative angiographic evaluation to verify complete aneurysmal occlusion/obliteration and preservation of normal adjacent vasculture. Recently, ICG videoangiography has become a widely used intra-operative adjunct and is an important tool used to assess complete occlusion and vessel patency at the conclusion of clip reconstruction. In this report, we outline the comprehensive and concurrent utilization of both vascular imaging modalities to ensure safe and complete occlusion of a mycotic aneurysm. Methods We describe our experience with a patient with left M4, Rolandic, enlarging mycotic aneurysm that was treated in a comprehensive fashion with microsurgery and intra-operative angiography (IA). Conclusions ICG videoangiography, in combination with concurrent intraoperative angiography in the setting of complex vascular lesions, may support intraoperative decision-making and provide demonstration of complete occlusion in an immediate fashion. A hybrid operative suite allows for high-quality imaging confirming complete resection.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 26
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: We have applied bipolar dual-lead spinal cord stimulation (SCS) between two cylinder-type electrodes placed on the ventral and dorsal sides of the spinal cord (dual-VD-SCS). A 36-year-old man suffered from burning pain from his right elbow down to his hand after brachial plexus avulsion. The areas with paresthesia induced by conventional SCS did not include the painful hand area. However, dual-VD-SCS completely induced paresthesia in the painful hand area. We speculate that dual-VD-SCS can be applied to stimulate deeper sites of the dorsal column and dorsal horn than conventional SCS and is useful for pain reduction.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 27
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background Ayub Ommaya proposed a surgical technique for subcutaneous reservoir and pump placement in 1963 to allow access to intraventricular cerebrospinal fluid (CSF). Currently, the most common indication for Ommaya reservoir insertion (ORI) in adults is for patients with hematologic or leptomeningeal disorders requiring repeated injection of chemotherapy into the CSF space. Historically, the intraventricular catheter has been inserted blindly based on anatomical landmarks. The purpose of this study was to examine short-term complication rates with ORI with image guidance (IG) and without image guidance (non-IG). Methods We retrospectively evaluated all operative cases of ORI from 2000 to 2014 by the senior author. Patient demographic data, surgical outcomes, and peri-operative complications were collected. Accurate placement and early (30-day) morbidity or mortality were considered primary outcomes. Results Fifty-five consecutive patients underwent ORI by the senior author over the study period (43.5 ± 16.6 years; 40.0% female). Indications for placement included acute lymphoblastic leukemia, diffuse large B-cell lymphoma, and leptomeningeal carcinomatosis. There were seven (12.7%) total complications: three (37.5%) with no-IG versus four (8.5%) with IG. Catheter malpositions were significantly higher in the non-IG group at 37.5% compared to 2.1%. Catheters were also more likely to require multiple passes with non-IG at 25% compare to 0% with IG. There were no early infections in either group. Conclusions We demonstrate improved accuracy and decreased complications using an image-guided approach compared with a traditional approach. Our results support routine use of intra-operative image guidance for proximal catheter insertion in elective ORI for intraventricular chemotherapy.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 28
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Idiopathic spinal cord herniation (ISCH) through an anterior dural defect is rare and the cause is uncertain. Recently, through interpreting imaging studies, disc herniation was proposed to be a major cause for ISCH. We describe the case of a 50-year-old woman with progressive myelopathy who was diagnosed with a thoracic spinal cord herniation. Microsurgical exploration revealed an anterior vertical dural defect and a small concomitant disc herniation, occult on the preoperative imaging, which caused the dural defect and led to ISCH. This intraoperative finding corroborates the emerging notion that disc herniation is the underlying cause of ISCH.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 29
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background Intraperitoneal pressure (IPP) counteracts the diversion of cerebrospinal fluid (CSF) from the cranial to the peritoneal compartment during ventriculoperitoneal shunting. Animal studies suggest that the intrinsic IPP exceeds the intraperitoneal hydrostatic pressure. The intrinsic IPP in mobile patients is relevant for shunt therapy, but data about it is not available. Methods The IPP was measured indirectly in 25 mobile subjects (13 female) by applying a standard intravesical pressure measurement technique. Measurements were carried out in reference to the navel (supine position) and the xiphoid (upright position). Results were adjusted for the intraperitoneal hydrostatic pressure and correlated afterward with general body measures. Results The corrected mean (SD) IPP measured in the supine position was 4.4 (4.5) cm H 2 O, and the mean (SD) upright IPP was 1.6 (7.8) cm H 2 O ( p  = 0.02). A positive correlation was found between the body mass index (BMI) and the IPP in the upright ( r  = 0.51) and supine ( r  = 0.65) body positions, and between the abdominal circumference and the IPP in the supine position ( r  = 0.63). Conclusions The intrinsic IPP in mobile subjects exceeds the intraperitoneal hydrostatic pressure. Thus, the intrinsic IPP counteracts the diversion of CSF into the peritoneal compartment. The intrinsic IPP is correlated with mobile patients’ general body measures.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 30
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background There are no uniform guidelines regarding when to operate for Lumbar Spinal Stenosis (LSS). As we apply findings from clinical research from one population to the next, elucidating similarities or differences provides important context for the validity of extrapolating clinical outcomes. The aim of this study was to compare the morphological severity of lumbar spinal stenosis on preoperative MRI in patients undergoing decompressive surgery in Boston, USA, and Trondheim, Norway. Methods In this observational retrospective study, we compared morphological severity on MRI before surgical treatment between two propensity score-matched patient populations with single or two-level symptomatic LSS. We assessed the radiographic severity of LSS utilizing the Schizas classification (grade A to D). Results Following propensity score matching, demographics are balanced. In the Trondheim cohort, two levels decompression were present in 36.2% of the patients vs. 41.9% in Boston, ( p  = 0.396). There was no significant difference in grades A to D concerning central stenosis ( p  = 0.075). When dichotomized in mild/moderate (A/B) and severe /extreme (C/D), there were no significant differences in the rate of levels operated for high-grade stenosis (C/D), 67.6% in the Boston group compare to 78.1% in the Trondheim group ( p  = 0.088). Conclusions Trondheim, Norway, and Boston, US, have similar radiographic thresholds of LSS for offering surgery.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 31
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Print ISSN: 0001-6322
    Electronic ISSN: 1432-0533
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 32
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Print ISSN: 0001-6322
    Electronic ISSN: 1432-0533
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 33
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Print ISSN: 0001-6322
    Electronic ISSN: 1432-0533
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 34
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The accuracy of reported sample results is contingent upon the quality of the assay calibration curve, and as such, calibration curves are critical components of ligand binding and other quantitative methods. Regulatory guidance and lead publications have defined many of the requirements for calibration curves which encompass design, acceptance criteria, and selection of a regression model. However, other important aspects such as preparation and editing guidelines have not been addressed by health authorities. The goal of this publication is to answer many of the commonly asked questions and to present a consensus and the shared views of members of the ligand binding assay (LBA) community on topics related to calibration curves with focus on providing recommendations for the preparation and editing of calibration curves.
    Electronic ISSN: 1550-7416
    Topics: Chemistry and Pharmacology
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 35
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Intranasal administration could be an attractive alternative route of administration for the delivery of drugs to the central nervous system (CNS). However, there are always doubts about the direct transport of therapeutics from nasal cavity to the CNS since there are only limited studies on the understanding of direct nose-to-brain transport. Therefore, this study aimed to (1) investigate the existence of nose-to-brain transport of intranasally administered HIV-1 replication inhibitor DB213 and (2) assess the direct nose-to-brain transport of unbound HIV-1 replication inhibitor DB213 quantitatively by a pharmacokinetic approach. Plasma samples were collected up to 6 h post-dosing after administration via intranasal or intravenous route at three bolus doses. In the brain-uptake study, the plasma, whole brain, and cerebrospinal fluid (CSF) were sampled between 15 min and 8 h post-dosing. All samples were analyzed with LC/MS/MS. Plasma, CSF, and brain concentration versus  time profiles were analyzed with nonlinear mixed-effect modeling. Structural model building was performed by NONMEM (version VII, level 2.0). Intranasal administration showed better potential to deliver HIV-1 replication inhibitor DB213 to the brain with 290-fold higher brain to plasma ratio compared with intravenous administration. Based on that, a model with two absorption compartments (nose-to-systemic circulation and nose-to-brain) was developed and demonstrated 72.4% of total absorbed unbound HIV-1 replication inhibitor DB213 after intranasal administration was transported directly into the brain through nose-to-brain pathway.
    Electronic ISSN: 1550-7416
    Topics: Chemistry and Pharmacology
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 36
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The American Association of Pharmaceutical Scientists (AAPS) biosimilar focus group on nonclinical and clinical assays has developed this manuscript to guide the industry on best practices and testing strategies when developing neutralizing antibody (NAb) assays for biosimilar programs. The immunogenicity assessment to biosimilar and originator drug products is one of the key aspects of clinical programs for biosimilars to demonstrate biosimilarity. Establishing that there are no clinically meaningful differences in immune response between a proposed product and the originator product is a key element in the demonstration of biosimilarity. It is critical to collect, evaluate, and compare the safety and immunogenicity data from the clinical pharmacology, safety, and/or efficacy studies especially when the originator drug product is known to have potential for immune-mediated toxicity. This manuscript aims to provide a comprehensive review and recommendations on assay formats, critical reagents, approaches to method development, and validation of the neutralizing antibody assays in extrapolation within the scope of biosimilar drug development programs. Even if there are multiple options on the development and validation of NAb assays for biosimilar programs, the type of drug and its MoA will help determine the assay format and technical platform for NAb assessment (e.g., cell-based or non-cell-based assay). We recommend to always perform a one-assay approach as it is better to confirm the biosimilarity using one-assay for NAb. If a one-assay approach is not feasible, then a two-assay format may be used. This manuscript will provide all the details necessary to develop NAb assays for biosimilars.
    Electronic ISSN: 1550-7416
    Topics: Chemistry and Pharmacology
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 37
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Despite the improvements in drug screening, high levels of drug attrition persist. Although high-throughput screening platforms permit the testing of compound libraries, poor compound efficacy or unexpected organ toxicity are major causes of attrition. Part of the reason for drug failure resides in the models employed, most of which are not representative of normal organ biology. This same problem affects all the major organs during drug development. Hepatotoxicity and cardiotoxicity are two interesting examples of organ disease and can present in the late stages of drug development, resulting in major cost and increased risk to the patient. Currently, cell-based systems used within industry rely on immortalized or primary cell lines from donated tissue. These models possess significant advantages and disadvantages, but in general display limited relevance to the organ of interest. Recently, stem cell technology has shown promise in drug development and has been proposed as an alternative to current industrial systems. These offerings will provide the field with exciting new models to study human organ biology at scale and in detail. We believe that the recent advances in production of stem cell-derived hepatocytes and cardiomyocytes combined with cutting-edge engineering technologies make them an attractive alternative to current screening models for drug discovery. This will lead to fast failing of poor drugs earlier in the process, delivering safer and more efficacious medicines for the patient.
    Electronic ISSN: 1550-7416
    Topics: Chemistry and Pharmacology
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 38
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: ABSTRACT The drug of abuse γ-hydroxybutyric acid (GHB) demonstrates complex toxicokinetics with dose-dependent metabolic and renal clearance. GHB is a substrate of monocarboxylate transporters (MCTs) which are responsible for the saturable renal reabsorption of GHB. MCT expression is observed in many tissues and therefore may impact the tissue distribution of GHB. The objective of the present study was to evaluate the tissue distribution kinetics of GHB at supratherapeutic doses. GHB (400, 600, and 800 mg/kg iv) or GHB 600 mg/kg plus l -lactate (330 mg/kg iv bolus followed by 121 mg/kg/h infusion) was administered to rats and blood and tissues were collected for up to 330 min post-dose. K p values for GHB varied in both a tissue- and dose-dependent manner and were less than 0.5 (except in the kidney). Nonlinear partitioning was observed in the liver (0.06 at 400 mg/kg to 0.30 at 800 mg/kg), kidney (0.62 at 400 mg/kg to 0.98 at 800 mg/kg), and heart (0.15 at 400 mg/kg to 0.29 at 800 mg/kg), with K p values increasing with dose consistent with saturation of transporter-mediated efflux. In contrast, lung partitioning decreased in a dose-dependent manner (0.43 at 400 mg/kg to 0.25 at 800 mg/kg) suggesting saturation of active uptake. l -lactate administration decreased K p values in liver, striatum, and hippocampus and increased K p values in lung and spleen. GHB demonstrates tissue-specific nonlinear distribution consistent with the involvement of monocarboxylate transporters. These observed complexities are likely due to the involvement of MCT1 and 4 with different affinities and directionality for GHB transport.
    Electronic ISSN: 1550-7416
    Topics: Chemistry and Pharmacology
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 39
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: According to the National Center of Health Statistics, cancer was the culprit of nearly 600,000 deaths in 2016 in the USA. It is by far one of the most heterogeneous diseases to treat. Treatment for metastasized cancers remains a challenge despite modern diagnostics and treatment regimens. For this reason, alternative approaches are needed. Chemoprevention using dietary phytochemicals such as triterpenoids, isothiocyanates, and curcumin in the prevention of initiation and/or progression of cancer poses a promising alternative strategy. However, significant challenges exist in the extrapolation of in vitro cell culture data to in vivo efficacy in animal models and to humans. In this review, the dose at which these phytochemicals elicit a response in vitro and in vivo of a multitude of cellular signaling pathways will be reviewed highlighting Nrf2-mediated antioxidative stress, anti-inflammation, epigenetics, cytoprotection, differentiation, and growth inhibition. The in vitro - in vivo dose response of phytochemicals can vary due, in part, to the cell line/animal model used, the assay system of the biomarker used for the readout, chemical structure of the functional analog of the phytochemical, and the source of compounds used for the treatment study. While the dose response varies across different experimental designs, the chemopreventive efficacy appears to remain and demonstrate the therapeutic potential of triterpenoids, isothiocyanates, and curcumin in cancer prevention and in health in general.
    Electronic ISSN: 1550-7416
    Topics: Chemistry and Pharmacology
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 40
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Multiple sclerosis (MS) is a highly heterogeneous disease with large inter-individual differences in disease course. MS lesion pathology shows considerable heterogeneity in localization, cellular content and degree of demyelination between patients. In this study, we investigated pathological correlates of disease course in MS using the autopsy cohort of the Netherlands Brain Bank (NBB), containing 182 MS brain donors. Using a standardized autopsy procedure including systematic dissection from standard locations, 3188 tissue blocks containing 7562 MS lesions were dissected. Unbiased measurements of lesion load were made using the tissue from standard locations. Lesion demyelinating and innate inflammatory activity were visualized by immunohistochemistry for proteolipid protein and human leukocyte antigen. Lesions were classified into active, mixed active/inactive (also known as chronic active), inactive or remyelinated, while microglia/macrophage morphology was classified as ramified, amoeboid or foamy. The severity score was calculated from the time from first symptoms to EDSS-6. Lesion type prevalence and microglia/macrophage morphology were analyzed in relation to clinical course, disease severity, lesion load and sex, and in relation to each other. This analysis shows for the first time that (1) in progressive MS, with a mean disease duration of 28.6 ± 13.3 years (mean ± SD), there is substantial inflammatory lesion activity at time to death. 57% of all lesions were either active or mixed active/inactive and 78% of all patients had a mixed active/inactive lesion present; (2) patients that had a more severe disease course show a higher proportion of mixed active/inactive lesions ( p  = 6e−06) and a higher lesion load ( p  = 2e−04) at the time of death, (3) patients with a progressive disease course show a higher lesion load ( p  = 0.001), and a lower proportion of remyelinated lesions ( p  = 0.03) compared to patients with a relapsing disease course, (4) males have a higher incidence of cortical grey matter lesions ( p  = 0.027) and a higher proportion of mixed active/inactive lesions compared to females across the whole cohort ( p  = 0.007). We confirm that there is a higher proportion of mixed active/inactive lesions ( p  = 0.006) in progressive MS compared to relapsing disease. Identification of mixed active/inactive lesions on MRI is necessary to determine whether they can be used as a prognostic tool in living MS patients.
    Print ISSN: 0001-6322
    Electronic ISSN: 1432-0533
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 41
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The condensate and bunker oil leaked from the Sanchi collision would cause a persistent impact on marine ecosystems in the surrounding areas. The long-term prediction for the distribution of the oil-polluted water and the information for the most affected regions would provide valuable information for the oceanic environment protection and pollution assessment. Based on the operational forecast system developed by the First Institute of Oceanography, State Oceanic Administration, we precisely predicted the drifting path of the oil tanker Sanchi after its collision. Trajectories of virtual oil particles show that the oil leaked from the Sanchi after it sank is mainly transported to the northeastern part of the sink location, and quickly goes to the open ocean along with the Kuroshio. Risk probability analysis based on the outcomes from the operational forecast system for years 2009 to 2017 shows that the most affected area is at the northeast of the sink location.
    Print ISSN: 0253-505X
    Electronic ISSN: 1869-1099
    Topics: Geosciences , Physics
    Published by Springer on behalf of The Chinese Society of Oceanography.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 42
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: An axisymmetric lower bound limit analysis technique in combination with the finite elements has been used to investigate the effect of considering a non-associated flow rule on the stability number ( γH / c ) for a vertical circular unsupported excavation in a general cohesive–frictional soil medium, where (1) H is the excavation height, (2) γ defines the unit weight of the soil mass, and (3) c indicates the cohesion of the soil mass. The results are derived for different magnitudes of dilative coefficient ( η ), friction angle ( ϕ ), and normalized excavation height ( H / b ), where b  = the radius of the excavation. The results clearly indicate the increase in γH / c with an increase in η value. It is expected that the charts provided in this note will be quite helpful for the practicing engineers.
    Print ISSN: 1861-1125
    Electronic ISSN: 1861-1133
    Topics: Geosciences
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 43
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The presence of underground voids has an adverse influence on the performance of shallow foundations. In this study, the bearing capacity and failure mechanism of footings placed on cohesive-frictional soils with voids are evaluated using discontinuity layout optimization. By introducing a reduction coefficient, a set of design charts that can be directly applied to the classical bearing capacity formulation is presented. The results indicate that the undrained bearing capacity with voids is sensitive to soil weight and cohesion, as both the bearing capacity and stability issues exist in the problem. The failure mechanism is directly related to a variety of soil properties, the locations of single voids, and the horizontal distance between two voids. The presence of voids has a more dominant effect on c – φ soils compared to that on undrained soil. An interpretation of the critical and adverse locations for single-void and dual-void cases with various soil strengths is presented.
    Print ISSN: 1861-1125
    Electronic ISSN: 1861-1133
    Topics: Geosciences
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 44
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The solutions of stress and displacement of a circular opening excavated in brittle and strain-softening rock mass incorporating rockbolts effectiveness and seepage force are presented in this study. The evolution equation is reconstructed for the strength parameters that incorporate these factors. Based on the evolution equation, an improved numerical method and stepwise procedure are presented which are compatible with the Mohr–Coulomb (M–C) and the generalized Hoek–Brown (H–B) failure criteria, respectively. Then given three interaction mechanisms between rockbolts and surrounding rock, solutions for stress and displacement are proposed in line with the improved numerical method and numerical stepwise procedure. The proposed approach can be reduced to Fahimifar and Soroush’s (Tunn Undergr Space Technol 20:333–343, 2005 ) solutions for special cases. The proposed method was validated by field monitoring data and FLAC results of Yanzidong tunnel. Examples under the M–C and generalized H–B failure criteria for rock mass are generated through MATLAB programming. Moreover, parametric studies are conducted to highlight the influence of rockbolts effectiveness in combination with seepage force on the stress and displacement of very good, average, and very poor surrounding rock. Results show that in this case, stress confinement is higher and tunnel convergences are lower than the corresponding stresses and displacements obtained in non-reinforced tunnels. Displacement and plastic radius are also higher than those without considering seepage force.
    Print ISSN: 1861-1125
    Electronic ISSN: 1861-1133
    Topics: Geosciences
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 45
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The focus of this paper is on quantitative evaluation of four different methods that use closed-form equations to calculate the nominal load in steel grid-reinforced soil walls under operational (end of construction) conditions. The four methods are the Coherent Gravity Method used in the UK, the AASHTO Simplified Method (USA), the PWRC Method used in Japan and the Simplified Stiffness Method. The accuracy of the methods is quantified based on analysis of bias statistics where bias is the ratio of measured to predicted (nominal) load. A large database of 113 measured reinforcement loads collected from 11 instrumented field walls is used in the study. For walls constructed with frictional soils, the Coherent Gravity Method and PWRC Method were the least accurate. The AASHTO Simplified Method demonstrated better accuracy and the Simplified Stiffness Method was the most accurate of all methods examined. The Coherent Gravity Method and the updated Simplified Stiffness Method for steel grid walls in the current study have the advantage that they can be used with soils that have a dependable soil cohesive strength component. However, the accuracy of the Simplified Stiffness Method was much better for all soil types based on bias analyses.
    Print ISSN: 1861-1125
    Electronic ISSN: 1861-1133
    Topics: Geosciences
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 46
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: This paper introduces X-ray tomography as an experimental method that allows grain-scale measurements for both porosity and degree of saturation. A whole configuration and set-up were developed specifically for the study of unsaturated Hostun sand and its water retention behaviour, using X-ray CT. A “step-by-step” protocol to obtain reconstructed volumes of sufficient quality where the three phases of the specimen can be clearly distinguished (i.e., grain, water and air) was also presented. A post-processing of the images helped the visualization and the characterization of the three phases within the specimen. A region growing separation tool was used to obtain trinarized volumes, allowing a qualitative/quantitative analysis to be performed. A qualitative interpretation of the resulting images has been done focusing on the water retention domains, where images of each different domain were retrieved for different suction values. Later, local measurements of relevant soil variables were conducted for a chosen subvolume of ≈ 3 ×  D 50 . This helped to build a map of measurement that covers the entire specimen field. Finally, water retention curve of Hostun sand was plotted and compared to a reference one. An investigation about the relation between the state variables: porosity and degree of saturation, for a constant suction, was performed. A noteworthy trend between porosity and degree of saturation was identified and discussed. The analysis presented in this study could be adapted for other granular materials, combined with pore size distribution and pore shape description, in order to understand the local relation between water retention behaviour characteristics and build a model that covers the whole retention behaviour of unsaturated granular materials.
    Print ISSN: 1861-1125
    Electronic ISSN: 1861-1133
    Topics: Geosciences
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 47
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: It is a well-known fact that addressing hydromechanical problems in saturated soils with the finite element method and equal-order interpolation formulations in displacements and pore pressures produces unstable results. Classically, stabilization has been achieved by increasing the interpolation degree of displacement with respect to pore pressure, hence fulfilling the Babuska–Brezzi condition. However, the use of quadratic elements involves high computational costs. From that point of view, the use of stabilized low-order elements is a more desirable option. Much research has been carried out in different directions in the stabilization of low-order formulations for saturated soils in quasistatic conditions, among others with the technique based on strain field enhancement through internal degrees of freedom. This article presents an alternative displacement–pore pressure formulation for saturated soil dynamics based on the enhancement of the displacement field through incompatible modes.
    Print ISSN: 1861-1125
    Electronic ISSN: 1861-1133
    Topics: Geosciences
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 48
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Hydraulic fracturing in permeable rock is a complicated process which might be influenced by various factors including the operational parameters (e.g., fluid viscosity, injection rate and borehole diameter) and the in situ conditions (e.g., in situ stress states and initial pore pressure level). To elucidate the effects of these variables, simulations are performed on hollow-squared samples at laboratory scale using fully coupled discrete element method. The model is first validated by comparing the stress around the borehole wall measured numerically with that calculated theoretically. Systematic parametric studies are then conducted. Modeling results reveal that the breakdown pressure and time to fracture stay constant when the viscosity is lower than 0.002 Pa s or higher than 0.2 Pa s but increases significantly when it is between 0.002 and 0.2 Pa s. Raising the injection rate can shorten the time to fracture but dramatically increase the breakdown pressure. Larger borehole diameter leads to the increase in the time to fracture and the reduction in the breakdown pressure. Higher in situ stress requires a longer injection time and higher breakdown pressure. The initial pore pressure, on the other hand, reduces the breakdown pressure as well as the time to fracture. The increase in breakdown pressure with viscosity or injection rate can be attributed to the size effect of greater tensile strength of samples with smaller infiltrated regions.
    Print ISSN: 1861-1125
    Electronic ISSN: 1861-1133
    Topics: Geosciences
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 49
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Wettability is a fundamental property controlling the extent of wetting in flat and granular solids. In natural soils, wettability affects a wide variety of processes including infiltration, preferential flow and surface runoff. In mineral processing, wettability is paramount in enhancing the efficiency of separation of minerals from gangue. The manipulation of surface wettability is equally crucial in many industrial applications. For instance, superhydrophobic surfaces are those on which water drops roll off easily and as such are used for self-cleaning applications. Therefore, while wettability is strongly cross-disciplinary, its evolution has been discipline-specific with a direct extrapolation or transfer of concepts, approaches, and methods to ground engineering unlikely to remain valid. This paper synthesizes relevant aspects from surface chemistry, materials science, mining engineering, and soil science, and discusses their implications within the context of new granular materials that resist wetting, for use in barriers or ground improvement and, in unsaturated soils, where the effects of wettability have been documented.
    Print ISSN: 1861-1125
    Electronic ISSN: 1861-1133
    Topics: Geosciences
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 50
    facet.materialart.
    Unknown
    Springer
    In: 4OR
    Publication Date: 2018-03-05
    Print ISSN: 1619-4500
    Electronic ISSN: 1614-2411
    Topics: Mathematics
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 51
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: An extensive field experiment for measurement of physical and chemical properties of aerosols was conducted at an urban site in the Chinese Academy of Meteorological Sciences (CAMS) in Beijing and at a rural site in Gucheng (GC), Hebei Province in December 2016. This paper compares the number size distribution of submicron particle matter (PM1, diameter 〈 1 μm) between the two sites. The results show that the mean PM1 number concentration at GC was twice that at CAMS, and the mass concentration was three times the amount at CAMS. It is found that the accumulation mode (100–850 nm) particles constituted the largest fraction of PM1 at GC, which was significantly correlated with the local coal combustion, as confirmed by a significant relationship between the accumulation mode and the absorption coefficient of soot particles. The high PM1 concentration at GC prevented the occurrence of new particle formation (NPF) events, while eight such events were observed at CAMS. During the NPF events, the mass fraction of sulfate increased significantly, indicating that sulfate played an important role in NPF. The contribution of regional transport to PM1 mass concentration was approximately 50% at both sites, same as that of the local emission. However, during the red-alert period when emission control took place, the contribution of regional transport was notably higher.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 52
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: We investigated the acidity and concentrations of water-soluble ions in PM 2.5 aerosol samples collected from an urban site in Beijing and a rural site in Gucheng, Hebei Province from November 2016 to January 2017 to gain an insight into the formation of secondary inorganic species. The average SO 4 2– , NO 3 – , and NH 4 + concentrations were 8.3, 12.5, and 14.1 μg m –3 , respectively, at the urban site and 14.0, 14.2, and 24.2 μg m –3 , respectively, at the rural site. The nitrogen and sulfur oxidation ratios in urban Beijing were correlated with relative humidity (with correlation coefficient r = 0.79 and 0.67, respectively) and the aerosol loadings. Based on a parameterization model, we found that the rate constant of the heterogeneous reactions for SO 2 on polluted days was about 10 times higher than that on clear days, suggesting that the heterogeneous reactions in the aerosol water played an essential role in haze events. The ISORROPIA II model was used to predict the aerosol pH, which had a mean (range) of 5.0 (4.9–5.2) and 5.3 (4.6–6.3) at the urban and rural site, respectively. Under the conditions with this predicted pH value, oxidation by dissolved NO 2 and the hydrolysis of N 2 O 5 may be the major heterogeneous reactions forming SO 4 2– and NO 3 – in haze. We also analyzed the sensitivity of the aerosol pH to changes in the concentrations of SO 4 2– , NO 3 – , and NH 4 + under haze conditions. The aerosol pH was more sensitive to the SO 4 2– and NH 4 + concentrations with opposing trends, than to the NO 3 – concentrations. The sensitivity of the pH was relatively weak overall, which was attributed to the buffering effect of NH 3 partitioning.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 53
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: We present mobile vehicle lidar observations in Tianjin, China during the spring, summer, and winter of 2016. Mobile observations were carried out along the city border road of Tianjin to obtain the vertical distribution characteristics of PM 2.5 . Hygroscopic growth was not considered since relative humidity was less than 60% during the observation experiments. PM 2.5 profile was obtained with the linear regression equation between the particle extinction coefficient and PM 2.5 mass concentration. In spring, the vertical distribution of PM 2.5 exhibited a hierarchical structure. In addition to a layer of particles that gathered near the ground, a portion of particles floated at 0.6–2.5-km height. In summer and winter, the fine particles basically gathered below 1 km near the ground. In spring and summer, the concentration of fine particles in the south was higher than that in the north because of the influence of south wind. In winter, the distribution of fine particles was opposite to that measured during spring and summer. High concentrations of PM 2.5 were observed in the rural areas of North Tianjin with a maximum of 350 μg m –3 on 13 December 2016. It is shown that industrial and ship emissions in spring and summer and coal combustion in winter were the major sources of fine particles that polluted Tianjin. The results provide insights into the mechanisms of haze formation and the effects of meteorological conditions during haze–fog pollution episodes in the Tianjin area.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 54
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Air pollution is a current global concern. The heavy air pollution episodes (HPEs) in Beijing in December 2016 severely influenced visibility and public health. This study aims to survey the chemical compositions, sources, and formation processes of the HPEs. An aerodyne quadruple aerosol mass spectrometer (Q-AMS) was utilized to measure the non-refractory PM1 (NR-PM1) mass concentration and size distributions of the main chemical components including organics, sulfate, nitrate, ammonium, and chloride in situ during 15–23 December 2016. The NR-PM1 mass concentration was found to increase from 6 to 188 μg m –3 within 5 days. During the most serious polluted episode, the PM1 mass concentration was about 2.6 times that during the first pollution stage and even 40 times that of the clean days. The formation rates of PM 2.5 in the five pollution stages were 26, 22, 22, 32, and 67 μg m –3 h –1 , respectively. Organics and nitrate occupied the largest proportion in the polluted episodes, whereas organics and sulfate dominated the submicron aerosol during the clean days. The size distribution of organics is always broader than those of other species, especially in the clean episodes. The peak sizes of the interested species grew gradually during different HPEs. Aqueous reaction might be important in forming sulfate and chloride, and nitrate was formed via oxidization and condensation processes. PMF (positive matrix factorization) analysis on AMS mass spectra was employed to separate the organics into different subtypes. Two types of secondary organic aerosol with different degrees of oxidation consisted of 43% of total organics. By contrast, primary organics from cooking, coal combustion, and traffic emissions comprised 57% of the organic aerosols during the HPEs.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 55
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The optical and radiative properties of aerosols during a severe haze episode from 15 to 22 December 2016 over Beijing, Shijiazhuang, and Jiaozuo in the North China Plain were analyzed based on the ground-based and satellite data, meteorological observations, and atmospheric environmental monitoring data. The aerosol optical depth at 500 nm was 〈 0.30 and increased to 〉 1.4 as the haze pollution developed. The Ångström exponent was 〉 0.80 for most of the study period. The daily single-scattering albedo was 〉 0.85 over all of the North China Plain on the most polluted days and was 〉 0.97 on some particular days. The volumes of fine and coarse mode particles during the haze event were approximately 0.05–0.21 and 0.01–0.43 μm 3 , respectively—that is, larger than those in the time without haze. The daily absorption aerosol optical depth was about 0.01–0.11 in Beijing, 0.01–0.13 in Shijiazhuang, and 0.01–0.04 in Jiaozuo, and the average absorption Ångström exponent varied between 0.6 and 2.0. The aerosol radiative forcing at the bottom of the atmosphere varied from –23 to –227,–34 to –199, and –29 to –191 W m –2 for the whole haze period, while the aerosol radiative forcing at the top of the atmosphere varied from –4 to –98, –10 to –51, and –21 to –143 W m –2 in Beijing, Shijiazhuang, and Jiaozuo, respectively. Satellite observations showed that smoke, polluted dust, and polluted continental components of aerosols may aggravate air pollution during haze episodes. The analysis of the potential source contribution function and concentration-weighted trajectory showed that the contribution from local emissions and pollutants transport from upstream areas were 190–450 and 100–410 μg m –3 , respectively.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 56
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The traditional method for computing the mean displacement in latitude–longitude coordinates is a spherical meridional–zonal resultant displacement method (MRDM), which regards the displacement as the resultant vector of the meridional and zonal displacement components. However, there are inhomogeneity and singularity in the computation error of the MRDM, especially at high latitudes. Using the NCEP/NCAR long-term monthly mean wind and idealized wind fields, the inhomogeneity in the MRDM was accessed by using a great circle displacement computing method (GCDM) for non-iterative cases. The MRDM and GCDM were also compared for iteration cases by taking the trajectories from a three-time level reference method as the real trajectories. In the horizontal direction, the GCDM assumes that an air particle moves along its locating great circle and that the magnitude of the displacement equals the arc length of the great circle. The inhomogeneity of the MRDM is evaluated in terms of the horizontal distance error from the products of wind speed, lapse time, and angle difference from the GCDM displacement orient. The non-iterative results show that the mean horizontal displacement computed through the MRDM has both computational and analytical errors. The displacement error of the MRDM depends on the wind speed, wind direction, and the departure latitude of the air particle. It increases with the wind speed and the departure latitude. The displacement magnitude error has a four-wave pattern and the displacement direction error has a two-wave feature in the definition range of the wind direction. The iterative result shows that the displacement magnitude error and angle error of the MRDM and GCDM with respect to the reference method increase with the lapse time and have similar distribution patterns. The mean magnitude error and the angle error of the MRDM are nearly twice as large as those of the GCDM.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 57
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Based on summer precipitation hindcasts for 1991–2013 produced by the Beijing Climate Center Climate System Model (BCC_CSM), the relationship between precipitation prediction error in northeastern China (NEC) and global sea surface temperature is analyzed, and dynamic–analogue prediction is carried out to improve the summer precipitation prediction skill of BCC_CSM, through taking care of model historical analogue prediction error in the real-time output. Seven correction schemes such as the systematic bias correction, pure statistical correction, dynamic–analogue correction, and so on, are designed and compared. Independent hindcast results show that the 5-yr average anomaly correlation coefficient (ACC) of summer precipitation is respectively improved from –0.13/0.15 to 0.16/0.24 for 2009–13/1991–95 when using the equally weighted dynamic–analogue correction in the BCC_CSM prediction, which takes the arithmetical mean of the correction based on regional average error and that on grid point error. In addition, probabilistic prediction using the results from the multiple correction schemes is also performed and it leads to further improved 5-yr average prediction accuracy.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 58
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: This study aims to detect the primary precursors and impact mechanisms for January surface temperature anomaly (JSTA) events in China against the background of global warming, by comparing the causes of two extreme JSTA events occurring in 2008 and 2011 with the common mechanisms inferred from all typical episodes during 1979–2008. The results show that these two extreme events exhibit atmospheric circulation patterns in the mid–high latitudes of Eurasia, with a positive anomaly center over the Ural Mountains and a negative one to the south of Lake Baikal (UMLB), which is a pattern quite similar to that for all the typical events. However, the Eurasian teleconnection patterns in the 2011 event, which are accompanied by a negative phase of the North Atlantic Oscillation, are different to those of the typical events and the 2008 event. We further find that a common anomalous signal appearing in early summer over the tropical Indian Ocean may be responsible for the following late-winter Eurasian teleconnections and the associated JSTA events in China. We show that sea surface temperature anomalies (SSTAs) in the preceding summer over the western Indian Ocean (WIO) are intimately related to the UMLB-like circulation pattern in the following January. Positive WIOSSTAs in early summer tend to induce strong UMLB-like circulation anomalies in January, which may result in anomalously or extremely cold events in China, which can also be successfully reproduced in model experiments. Our results suggest that the WIOSSTAs may be a useful precursor for predicting JSTA events in China.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 59
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The western North Pacific anomalous anticyclone (WNPAC) is an important atmospheric circulation system that conveys El Niño impact on East Asian climate. In this review paper, various theories on the formation and maintenance of the WNPAC, including warm pool atmosphere–ocean interaction, Indian Ocean capacitor, a combination mode that emphasizes nonlinear interaction between ENSO and annual cycle, moist enthalpy advection/Rossby wave modulation, and central Pacific SST forcing, are discussed. It is concluded that local atmosphere–ocean interaction and moist enthalpy advection/Rossby wave modulation mechanisms are essential for the initial development and maintenance of the WNPAC during El Niño mature winter and subsequent spring. The Indian Ocean capacitor mechanism does not contribute to the earlier development but helps maintain the WNPAC in El Niño decaying summer. The cold SST anomaly in the western North Pacific, although damped in the summer, also plays a role. An interbasin atmosphere–ocean interaction across the Indo-Pacific warm pool emerges as a new mechanism in summer. In addition, the central Pacific cold SST anomaly may induce the WNPAC during rapid El Niño decaying/La Niña developing or La Niña persisting summer. The near-annual periods predicted by the combination mode theory are hardly detected from observations and thus do not contribute to the formation of the WNPAC. The tropical Atlantic may have a capacitor effect similar to the tropical Indian Ocean.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 60
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Urban microclimate peculiarities in two Arctic cities in northwestern Russia—Kirovsk (67.62°N, 33.67°E) and Apatity (67.57°N, 33.38°E)—were investigated by using mobile temperature records. The experiment was carried out in and around Apatity and Kirovsk in February 2014 and December 2016. The DS18B20 digital thermometer was installed on the roof of a car (height: approximately 1.2 m) to measure and record temperature variations automatically. In addition to the digital thermometer, the car was also equipped with an onboard global positioning system, allowing every temperature measurement to be referenced with an altitude and a latitude/longitude position. The possibility of urban heat island formation in these polar cities, above the Arctic Circle, was studied. Our analysis indicated that on 11 February 2014, the temperature varied in accordance with the background environmental lapse rate (–0.0045°C m –1 ), and nearly corresponded to it (–0.0165°C m –1 ) on 12 February 2014. On 6 December 2016, a strong local temperature inversion with a positive value of 0.032°C m –1 was detected, seemingly caused by the formation of a cold air pool in the valley near Kirovsk. It was found that the temperature variations within and outside these cities are strongly influenced by local topographic effects and the physical conditions of the atmospheric boundary layer.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 61
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background This study aims to assess surgical outcome in brain tumor surgery using patient reported outcome measures (PROMs) and to compare their results with traditional clinical outcome measurements. Method Neuro-oncological patients undergoing surgical removal for the lesion were enrolled; MOCA test, PROMs (EUROHIS-QoL, PGWB-S, WHODAS-12), and the clinical scale Karnofsky Performance Status (KPS) were administered to evaluate respectively cognitive status, quality of life, well-being, disability, and functional status before surgery and at 3-month follow-up. Wilcoxon test was performed to evaluate the longitudinal change of test scores, the smallest detectable difference to classify the change of patients in PROMs, the Cohen kappa to investigate the concordance between KPS and PROMs in classifying the patients’ change, and Mann-Whitney U test to compare patients with complications and no complications. Results A total of 101 patients were enrolled (54 woman, mean age 50.2 ± 14.1, range 20–85): psychological well-being improved at follow-up; 95 patients (94.1%) were improved/unchanged and 6 (5.9%) were worsened according to PROMs; functional status measured with KPS had a slight agreement with quality of life and disability and no agreement with psychological well-being questionnaires; patients with complications had a greater worsening in KPS. Conclusions According to PROMs measuring QoL, disability, and psychological well-being, most of the patients were improved/unchanged after surgery. Since PROMs and KPS detect different aspects of the patients’ health status, PROMs should be integrated in surgical outcome evaluation. Furthermore, their association with complications and with other clinical and subjective variables that could influence patient’s perception of health status should be investigated.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 62
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Background Brain metastases from hepatocellular carcinoma (HCC) are rare, but their incidence is increasing because of developments in recent therapeutic advances. The purpose of this study was to investigate the characteristics of brain metastases from HCC, to evaluate the predictive factors, and to assess the efficacy of gamma knife surgery (GKS). Method A retrospective study was performed on patients with brain metastases from HCC who were treated at Tokyo Gamma Unit Center from 2005 to 2014. Results Nineteen patients were identified. The median age at diagnosis of brain metastases was 67.0 years. Fifteen patients were male and four patients were female. Six patients were infected with hepatitis B virus (HBV). Two patients were infected with hepatitis C virus (HCV). Eleven patients were not infected with HBV or HCV. The median interval from the diagnosis of HCC to brain metastases was 32.0 months. The median number of brain metastases was two. The median Karnofsky performance score at first GKS was 70. The median survival time following brain metastases was 21.0 weeks. Six-month and 1-year survival rates were 41.2 and 0%, respectively. One month after GKS, no tumor showed progressive disease. The HBV infection (positive vs. negative) was significantly associated with survival according to univariate analysis ( p  = 0.002). Conclusions The patients having brain metastases from HCC had poor prognosis and low performance state. Therefore, GKS is an acceptable option for controlling brain metastases from HCC because GKS is noninvasive remedy and local control is reasonable.
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 63
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Black carbon (BC) is a component of fine particulate matter (PM 2.5 ), associated with climate, weather, air quality, and people’s health. However, studies on temporal variation of atmospheric BC concentration at background stations in China and its source area identification are lacking. In this paper, we use 2-yr BC observations from two background stations, Lin’an (LAN) and Longfengshan (LFS), to perform the investigation. The results show that the mean diurnal variation of BC has two significant peaks at LAN while different characteristics are found in the BC variation at LFS, which are probably caused by the difference in emission source contributions. Seasonal variation of monthly BC shows double peaks at LAN but a single peak at LFS. The annual mean concentrations of BC at LAN and LFS decrease by 1.63 and 0.26 μg m –3 from 2009 to 2010, respectively. The annual background concentration of BC at LAN is twice higher than that at LFS. The major source of the LAN BC is industrial emission while the source of the LFS BC is residential emission. Based on transport climatology on a 7-day timescale, LAN and LFS stations are sensitive to surface emissions respectively in belt or approximately circular area, which are dominated by summer monsoon or colder land air flows in Northwest China. In addition, we statistically analyze the BC source regions by using BC observation and FLEXible PARTicle dispersion model (FLEXPART) simulation. In summer, the source regions of BC are distributed in the northwest and south of LAN and the southwest of LFS. Low BC concentration is closely related to air mass from the sea. In winter, the source regions of BC are concentrated in the west and south of LAN and the northeast of the threshold area of s tot at LFS. The cold air mass in the northwest plays an important role in the purification of atmospheric BC. On a yearly scale, sources of BC are approximately from five provinces in the northwest/southeast of LAN and the west of LFS. These findings are helpful in reducing BC emission and controlling air pollution.
    Print ISSN: 0894-0525
    Topics: Geosciences
    Published by Springer on behalf of The Chinese Meteorological Society.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 64
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 65
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Print ISSN: 0001-6268
    Electronic ISSN: 0942-0940
    Topics: Medicine
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 66
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The biotic (bacteria, fungi, pollen grains, algae) and abiotic (dust mites) factors present in the atmosphere are responsible for the common allergic reactions in humans. Fungi are one of the major biotic factors resulting in allergic conditions and sometimes lead to fatal diseases affecting vital organs. A detailed survey was carried out for 2 years (from May 2014 to April 2016) to assess the seasonal distribution and comparative diversity of aeromycoflora present in the urban and rural areas of Bilaspur, Chhattisgarh (India). During the survey, a marked variation in the types of fungal isolates and their colonies were observed in the samples collected at study sites. The maximum number of fungal colonies was obtained in the month of October and November during the first and second year, respectively. Among the isolates, Aspergillus and Curvularia sp. were found with the highest percent frequency and percent contribution. The predominant fungal species observed during the survey were Aspergillus fumigatus, Aspergillus niger, Aspergillus flavus, Penicillium sp. and Alternaria alternata which are known to cause different types of diseases including allergy in human beings, suggesting the possibility of occurrence of fungal allergy in the human population of Bilaspur.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 67
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: In this study, a Tauber pollen trap was used in the urban area of Shijiazhuang to monitor continuously the outdoor air pollen from 2007 to 2011. The trap was emptied at regular intervals (typically 15 days). The results show that airborne pollen assemblages are generally similar each year among 2007–2011 and are responsive to the flowering times of plants, being dominated by pollen from woody plants in the spring and by pollen from herbaceous plants in summer and autumn. Two peak pollen influx periods, especially for the main allergenic pollen taxa, are seen, one between early March to early June and a second between late August to early October. During the four seasons, the main pollen taxa are Juglans , Artemisia , Platanus , Populus , Chenopodiaceae, Urtica  +  Humulus , Rosaceae, Pinus , Poaceae, Cereals, Quercus, and Betula , and all taxa other than Rosaceae were confirmed by relevant studies to be allergenic pollen taxa. RDA analysis of pollen influx and meteorological factors shows that in spring, temperature and humidity have significant effects on the pollen influx of woody plants; in summer, humidity and precipitation have significant negative effects on pollen influx of herbaceous plants; in autumn, temperature, water vapor pressure, and precipitation have a significant positive influence on herbaceous pollen influx; in winter, there were no significant correlations between airborne pollen influx and meteorological factors. The results reveal the dispersion patterns of airborne pollen and provide an important reference to appropriate construction of urban green systems and the reliable reduction in regional pollinosis.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 68
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Members of Cupressaceae and Taxaceae are known to release large amounts of highly allergenic pollen grains into the atmosphere, which are responsible for the onset of pollinosis in many countries throughout the world. In addition to pollen grains, their pollen sacs produce orbicules, which are submicron particles reported to carry allergens and which are potentially able to reach much further down the respiratory tract than pollen grains. Previous research has postulated the presence of orbicules in the atmosphere; however, direct observations have not yet been reported. The aim of this research was to provide the first direct evidence that Cupressaceae orbicules are released into the atmosphere by detecting them in daily aerobiological samples. We observed pollen sacs, pollen grains, and orbicules of nine species of Cupressaceae using scanning electron microscope (SEM). We then used a light and confocal microscope, to examine daily aerobiological samples. Under SEM, we measured the orbicule size (0.494–0.777 µm) and detected unknown nanometric particles (130–200 nm). Under the light microscope, aerobiological samples showed clusters of stained dots surrounding the pollen grains of Cupressaceae. Under the confocal microscope, the same clusters were resolved into submicron particles with the same autofluorescence as the pollen grains. These features enabled us to identify them as orbicules. We believe that our findings help to explain the onset of pollinosis and allergic asthma related to Cupressaceae pollen grains in many countries, even before pollen grains are actually detected or after they are no longer observed in aerobiological monitoring samples.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 69
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Relationships between meteorological factors and airborne pollen concentrations at high altitudes are virtually unknown. We used cross-correlation analyses to test the relationships between daily variation in meteorological factors (i.e. temperature, humidity and wind speed) and airborne pollen concentration, diversity (number of families and Shannon and Simpson diversity indices) and evenness (Pielou index) in an Apennine high-altitude site (Gran Sasso Massif, 2117 m elevation). In contrast to patterns observed at low altitudes, the temperature had a negative correlation with pollen abundance and diversity, whereas humidity had a positive correlation. The unexpected negative correlations with temperature can be explained with the particular position of our sampling site. Wind speed was positively correlated with pollen diversity and abundance in the short term, which can be explained by the fact that higher wind speed promotes both primary emission of pollen from the anthers and subsequent re-suspension. Evenness and wind speed were negatively correlated in the short term because of the different response of different species to meteorological conditions. In the longer term, the average concentrations of the various taxa tend to reach similar values, leading to increased values of diversity. Our finding of a decrease in pollen emission with increasing temperature has important implications for the study of the impacts of global change on high-altitude plant communities. We also detected a high abundance of Cupressaceae/Taxaceae pollen, a reflection of the expansion of thermophilic species, such as Juniperus, due to climate change.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 70
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Numerous studies have focused on occupational and indoor environments because people spend more than 90% of their time in them. Nevertheless, air is the main source of bacteria in indoors, and outdoor exposure is also crucial. Worldwide studies have indicated that bacterial concentrations vary among different types of outdoor environments, with considerable seasonal variations as well. Conducting comprehensive monitoring of atmospheric aerosol concentrations is very important not only for environmental management but also for the assessment of the health impacts of air pollution. To our knowledge, this is the first study to present outdoor and seasonal changes of bioaerosol data regarding an urban area of Poland. This study aimed to characterize culturable bacteria populations present in outdoor air in Gliwice, Upper Silesia Region, Poland, over the course of four seasons (spring, summer, autumn and winter) through quantification and identification procedures. In this study, the samples of bioaerosol were collected using a six-stage Andersen cascade impactor (with aerodynamic cut-off diameters of 7.0, 4.7, 3.3, 2.1, 1.1 and 0.65 μm). Results showed that the concentration of airborne bacteria ranged from 4 CFU m −3 , measured on one winter day, to a maximum equal to 669 CFU m −3 on a spring day. The average size of culturable bacterial aerosol over the study period was 199 CFU m −3 . The maximal seasonally averaged concentration was found in the spring season and reached 306 CFU m −3 , and the minimal seasonally averaged concentration was found in the winter 49 CFU m −3 . The most prevalent bacteria found outdoors were gram-positive rods that form endospores. Statistically, the most important meteorological factors related to the viability of airborne bacteria were temperature and UV radiation. These results may contribute to the promotion and implementation of preventative public health programmes and the formulation of recommendations aimed at providing healthier outdoor environments.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 71
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The management of fungal contaminants inside libraries and archives has become a big challenge for librarians, restorers and scientists. Several disinfection treatments have been developed in recent years, using both chemical and physical approaches on book collections and indoor environments. However, there is a lack of knowledge about the temporal efficiency of these cleanings, especially in relation with the preservation environments. The aim of this study was to determine the long-term effect of a chemical disinfection that interested a previous-contaminated book collection inside a University library. The monitoring after 6 months and 1 year from the cleaning confirmed any fungal growth on the disinfected books and the reduction of 90% of the airborne fungal load, highlighting anyway the presence of high fungal diversity. Sixty-eight different airborne fungal entities were isolated, in particular Aspergillus vitricola, Bulleromyces albus, Cladosporium cladosporioides, Cladosporium pseudocladosporioides, Cladosporium sphaerospermum, Penicillium brevicompactum , Rodothorula mugillaginosa and Sporodiobolus pararoseus. Several fungal species were sampled from the disinfected books, in particular Aspergillus penicillioides and Penicillium chrysogenum . The presence of these fungi both as airborne and as settled particles highlights the importance to maintain clean the preservation environments in order to prevent further microbial contaminations.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 72
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Introduction Fungal spores constitute an important fraction of bioaerosols in the atmosphere. Objectives To analyse the content of Alternaria and Cladosporium spores in the atmosphere of Beja and the effect of meteorological conditions on their concentrations. Methodology The daily and hourly data of Alternaria and Cladosporium fungal spores concentration in the atmosphere of Beja were monitored from April 12, 2012 to July 30, 2014, based on the Portuguese Aerobiology Network methodology. The influence of meteorological conditions on the studied types of fungal spore concentrations was assessed through Spearman’s correlation analysis. Results During the study period, 20,741 Alternaria spores and 320,862 Cladosporium spores were counted. In 2013, there were 5,822 Alternaria spores and 123,864 Cladosporium spores. The absolute maximum concentrations of Alternaria and Cladosporium spores were recorded on November 8, 2013, with 211 and 1301 spores/m 3 , respectively. Temperature, insolation and wind direction parameters showed a positive correlation with Alternaria and Cladosporium spore levels, while relative humidity and precipitation presented a negative correlation, which is statistically significant. Wind speed only showed a statistically significant positive correlation in terms of Alternaria spore levels. Conclusion Alternaria and Cladosporium spores are present in the atmospheric air of Beja throughout the year, with the highest concentration period occurring during spring and autumn. There was a clear effect of meteorological parameters on airborne concentrations of these fungal spores.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 73
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Fungal spores are normal components of external environments. They have been reported to be associated with human, animal and plant diseases causing primary and opportunistic infections. Cladosporium is commonly the most frequently isolated genus from air samples, and its species are considered mainly saprophytic, but there is a wide variety of taxa that can cause adverse effects on human and animal health and also on plants. In this work, we aimed to record Cladosporium spores frequency of isolation in northern Argentinean Patagonia and to perform a molecular characterization based on actin gene complemented with EF1α and ITS genes. The ability of the pathogens to cause disease in pip fruits of Packham’s Triumph and Abate Fetel pears and red delicious apples was determined. Results confirmed Cladosporium spores as the main genera isolated from air samples, and the molecular characterization revealed the existence of 11 species in this region grouped in C. cladosporioides and C. herbarum complexes. Pathogenicity tests revealed that Cladosporium sp. cause disease on fruit. Abate Fetel was the most susceptible to infection. These results compose the first study in Argentina in respect of identification at species level of airborne Cladosporium spores, and furthermore, it is the first report in northern Patagonia and the high valley of Río Negro productive region. This knowledge can help farmers to take preventive measures in order to avoid biological damage.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 74
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The composition of fungal biota and air quality of five traditional subterranean wine cellars and one store building of a modern wine production facility were examined in the Tokaj wine region (northeastern Hungary). Air samples were collected with SAS IAQ sampler onto PDA, MEA and RBA. Strains representing morphotypes were isolated from colonies formed on agar plates from either air or surface samples. The internal transcribed spacer (ITS) region of the rRNA gene cluster was amplified with primers ITS1 and ITS4. Altogether 90 morphotypes were isolated, 48 and 12 strains (43 species) from the air and surfaces, respectively. The number of spore-forming species generated high diversity of indoor fungi and differences between the cellars’ fungal compositions; however, their dominant species were proved to be the same. Among the isolated strains Penicillium spp. were the most frequent. The walls of cellars were covered by colonies of Zasmidium ( Cladosporium ) cellare often referred to as a noble mold. Even so, this mold has been found only at a small concentration in the air samples (10–30 CFU/m 3 ). The walls of the modern store were free of molds. Diversity of fungi of the examined wine cellars was influenced by environmental conditions to a certain degree, such as elevation (height above sea level), age, reconstruction time of cellars, indoor ethanol concentration and the number of chimneys. The location of cellars poorly influenced the concentration of fungi of the air inside cellars, contrary to outdoors where the air of the municipal area contained more CFUs than that of rural spaces.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 75
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: This paper analyses long-term (1960–2015) onset of flowering in 16 native terrestrial plants (11 of them produce important allergens) recorded in different parts of the Czech Republic (southern, central and northern part) in relation to the North Atlantic Oscillation (NAO) index of the preceding winter and thermal data—growing degree-days (GDD) and soil temperature. Flowering occurred significantly earlier following positive winter NAO phases (causing spring to be warmer than normal in Central Europe) in nearly all early-flowering (February, March, April) species; high Pearson correlation values were recorded in, e.g. wood anemone, common snowdrop, goat willow, common hazel and common alder. There was found a difference between the southern and northern part of the country, e.g. in silver birch and pedunculate oak. Out of the later-flowering (May–July) plant species, black elder and meadow foxtail also significantly correlated with the winter NAO index, lime tree correlated less markedly. The best results of a threshold for calculation of GDD to onset of beginning of flowering were found in lime tree—it was 5 °C at all three stations. Results of other taxa were more variable (e.g. 4–7 °C in goat willow; 6–10 °C in silver birch). Pearson correlation coefficients between NAO index and GDD were negative in lime tree at all thresholds (5, 6, 7, 8, 9, 10 °C), while goat willow and silver birch were not so uniform (both positive and negative values). Correlation coefficients between phenophase onset and soil temperature (10 cm depth) had the highest values in silver birch, European larch and wood anemone. Stations situated at higher elevation showed negative correlation coefficient with soil temperature in common snowdrop, pedunculate oak, meadow foxtail and lime tree; other values were positive.
    Print ISSN: 0393-5965
    Electronic ISSN: 1573-3025
    Topics: Biology
    Published by Springer
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 76
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The application of numerical weather prediction (NWP) products is increasing dramatically. Existing reports indicate that ensemble predictions have better skill than deterministic forecasts. In this study, numerical ensemble precipitation forecasts in the TIGGE database were evaluated using deterministic, dichotomous (yes/no), and probabilistic techniques over Iran for the period 2008–16. Thirteen rain gauges spread over eight homogeneous precipitation regimes were selected for evaluation. The Inverse Distance Weighting and Kriging methods were adopted for interpolation of the prediction values, downscaled to the stations at lead times of one to three days. To enhance the forecast quality, NWP values were post-processed via Bayesian Model Averaging. The results showed that ECMWF had better scores than other products. However, products of all centers underestimated precipitation in high precipitation regions while overestimating precipitation in other regions. This points to a systematic bias in forecasts and demands application of bias correction techniques. Based on dichotomous evaluation, NCEP did better at most stations, although all centers overpredicted the number of precipitation events. Compared to those of ECMWF and NCEP, UKMO yielded higher scores in mountainous regions, but performed poorly at other selected stations. Furthermore, the evaluations showed that all centers had better skill in wet than in dry seasons. The quality of post-processed predictions was better than those of the raw predictions. In conclusion, the accuracy of the NWP predictions made by the selected centers could be classified as medium over Iran, while post-processing of predictions is recommended to improve the quality.
    Print ISSN: 0256-1530
    Electronic ISSN: 1861-9533
    Topics: Physics
    Published by Springer on behalf of Science Press.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 77
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The “summer prediction barrier” (SPB) of SST anomalies (SSTA) over the Kuroshio–Oyashio Extension (KOE) refers to the phenomenon that prediction errors of KOE-SSTA tend to increase rapidly during boreal summer, resulting in large prediction uncertainties. The fast error growth associated with the SPB occurs in the mature-to-decaying transition phase, which is usually during the August–September–October (ASO) season, of the KOE-SSTA events to be predicted. Thus, the role of KOE-SSTA evolutionary characteristics in the transition phase in inducing the SPB is explored by performing perfect model predictability experiments in a coupled model, indicating that the SSTA events with larger mature-to-decaying transition rates (Category-1) favor a greater possibility of yielding a more significant SPB than those events with smaller transition rates (Category-2). The KOE-SSTA events in Category-1 tend to have more significant anomalous Ekman pumping in their transition phase, resulting in larger prediction errors of vertical oceanic temperature advection associated with the SSTA events. Consequently, Category-1 events possess faster error growth and larger prediction errors. In addition, the anomalous Ekman upwelling (downwelling) in the ASO season also causes SSTA cooling (warming), accelerating the transition rates of warm (cold) KOE-SSTA events. Therefore, the SSTA transition rate and error growth rate are both related with the anomalous Ekman pumping of the SSTA events to be predicted in their transition phase. This may explain why the SSTA events transferring more rapidly from the mature to decaying phase tend to have a greater possibility of yielding a more significant SPB.
    Print ISSN: 0256-1530
    Electronic ISSN: 1861-9533
    Topics: Physics
    Published by Springer on behalf of Science Press.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 78
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: Variations in the high-frequency oscillations of tropical cyclones (TCs) over the western North Pacific (WNP) are studied in numerical model simulations. Power spectrum analysis of maximum wind speeds at 10 m (MWS 10 ) from an ensemble of 15 simulated TCs shows that oscillations are significant for all TCs. The magnitudes of oscillations in MWS 10 are similar in the WNP and South China Sea (SCS); however, the mean of the averaged significant periods in the SCS (1.93 h) is shorter than that in the open water of the WNP (2.83 h). The shorter period in the SCS is examined through an ensemble of simulations, and a case simulation as well as a sensitivity experiment in which the continent is replaced by ocean for Typhoon Hagupit (2008). The analysis of the convergence efficiency within the boundary layer suggests that the shorter periods in the SCS are possibly due to the stronger terrain effect, which intensifies convergence through greater friction. The enhanced convergence strengthens the disturbance of the gradient and thermal wind balances, and then contributes to the shorter oscillation periods in the SCS.
    Print ISSN: 0256-1530
    Electronic ISSN: 1861-9533
    Topics: Physics
    Published by Springer on behalf of Science Press.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 79
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Print ISSN: 0256-1530
    Electronic ISSN: 1861-9533
    Topics: Physics
    Published by Springer on behalf of Science Press.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 80
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The chromosomes of spinyhead croaker Collichthys lucidus (Richardson, 1844) were characterized for the first time by fluorescence staining, self genomic in situ hybridization (self-GISH), and multicolor fluorescence in situ hybridization (FISH) with 18S rDNA, 5S rDNA and telomeric sequence probes. The female karyotype has exclusively 24 pairs of acrocentric chromosomes (2n=48a, NF=48), while the male one consists of 22 pairs of acrocentric chromosomes, 2 monosomic acrocentric chromosomes and a metacentric chromosome (2n=1m+46a, NF=48). The difference between female and male karyotypes indicates the presence of a sex chromosome of X 1 X 1 X 2 X 2 /X 1 X 2 Y type, where Y is the unique metacentric chromosome in the male karyotype. As revealed by FISH, 5S rDNA and 18S rDNA sites were mapped at syntenic position of the largest acrocentric chromosome (X 1 ), and the short arms of the Y chromosome as well. An X 1 -chromosome specific interstitial telomeric signal (ITS) was detected overlapping the 5S rDNA sites. In addition, self-GISH revealed that the repetitive DNAs accumulated on all the putative sex chromosome. Chromosome fusion accompanied by a partial deletion in the ancestral karyotype (2n=48a) is hypothesized for the origin of such multiple sex chromosome system. The present study, as the first description of differentiated sex chromosome in family Sciaenidae, will give clues to the studies on the sex chromosome of other Sciaenids.
    Print ISSN: 0253-505X
    Electronic ISSN: 1869-1099
    Topics: Geosciences , Physics
    Published by Springer on behalf of The Chinese Society of Oceanography.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 81
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: A new method to determine wave directions from nautical X-band images is proposed. The signatures of ocean waves show obvious scale and directional characteristics in nautical X-band radar images. Curvelet transform (CT) possesses very high scale and directional sensitivities. Therefore, it has good capability to analyze ocean wave fields. The radar images are decomposed at different scales, in different directions, and at different positions by CT, and curvelet coefficients are obtained. Given to the scale and directional characteristics of surface waves, the information of ocean waves is centralized in the curvelet coefficients of certain directions and at certain scales. Therefore, the wave orientations can be determined. The 180 ambiguity is removed by calculating crosscorrelation coefficients (CCCs) between continuous collected images. The proposed method is verified by the dataset collected on the Northwest coast of the Zhangzi Island in the Yellow Sea of China from March to April 2009.
    Print ISSN: 0253-505X
    Electronic ISSN: 1869-1099
    Topics: Geosciences , Physics
    Published by Springer on behalf of The Chinese Society of Oceanography.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 82
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-05
    Description: The natural gas generation process is simulated by heating source rocks of the Yacheng Formation, including the onshore-offshore mudstone and coal with kerogens of Type II2-III in the Qiongdongnan Basin. The aim is to quantify the natural gas generation from the Yacheng Formation and to evaluate the geological prediction and kinetic parameters using an optimization procedure based on the basin modeling of the shallow-water area. For this, the hydrocarbons produced have been grouped into four classes (C 1 C 2 C 3 and C 4-6 ). The results show that the onset temperature of methane generation is predicted to occur at 110°C during the thermal history of sediments since 5.3 Ma by using data extrapolation. The hydrocarbon potential for ethane, propane and heavy gaseous hydrocarbons (C 4-6 ) is found to be almost exhausted at geological temperature of 200°C when the transformation ratio (TR) is over 0.8, but for which methane is determined to be about 0.5 in the shallow-water area. In contrast, the end temperature of the methane generation in the deep-water area was over 300°C with a TR over 0.8. It plays an important role in the natural gas exploration of the deep-water basin and other basins in the broad ocean areas of China. Therefore, the natural gas exploration for the deep-water area in the Qiongdongnan Basin shall first aim at the structural traps in the Ledong, Lingshui and Beijiao sags, and in the forward direction of the structure around the sags, and then gradually develop toward the non-structural trap in the deep-water area basin of the broad ocean areas of China.
    Print ISSN: 0253-505X
    Electronic ISSN: 1869-1099
    Topics: Geosciences , Physics
    Published by Springer on behalf of The Chinese Society of Oceanography.
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 83
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-06
    Description: Urban farming, especially on rooftops, is a popular and growing topic in both the media and the scientific literature, providing a genuine opportunity to meet some of the challenges linked to urban development worldwide. However, relatively little attention has been paid to date to the growing medium of green roofs, i.e., Technosols. A better understanding of the influence of Technosols and the link with ecosystem services is required in order to maximize the environmental benefits of urban rooftop farming. Between March 2013 and March 2015, a pilot project called T4P (Parisian Productive rooftoP, Pilot Experiment) was conducted on the rooftop of AgroParisTech University. Urban organic waste was used, and results were compared with those obtained using a commercial potting soil, based on yield and trace metal concentrations, substrate characterization, and the amount of leaching. An assessment of the ecosystem services expected from the Technosols was undertaken in terms of the output of food (food production and quality), regulation of water runoff (quantity and quality), and the recycling of organic waste. Indicators of these ecosystem services (e.g., yield, annual loss of mass of mineral nitrogen) were identified, measured, and compared with reference cases (asphalt roof, green roof, and cropland). Measured yields were almost equivalent to those obtained from horticultural sources in the same area, and the Technosols also retained 74–84% of the incoming rainfall water. This is the first quantitative analysis of ecosystem services delivered by urban garden rooftops developed on organic wastes, and demonstrates their multifunctional character, as well as allowing the identification of trade-offs. An ecosystem services approach is proposed for the design of soil-based green infrastructure of this kind and more generally for the design of sustainable urban agriculture.
    Print ISSN: 1774-0746
    Electronic ISSN: 1773-0155
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 84
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-06
    Description: The integration of crop and livestock systems has been recognized for its potential to reduce the environmental impacts associated with agriculture and improve farmer livelihoods. However, to date, most research has focused on the integration of cattle into crop and pasture systems. Here, we examine the integration of sheep into vineyards and assess farmers’ perceived benefits and costs of the practice. Viticulture expansion has led to significant land use change in recent years and new environmental challenges, particularly with respect to herbicide use. Sheep integration into vineyards offers the potential to utilize the synergies of both systems to reduce external inputs, promote soil health, and increase farmer profit. Our study focuses in New Zealand, the world’s 15th largest wine producer, particularly in Marlborough, which produces 75% of the country’s wine. As a result, the case study is an excellent representation of New Zealand viticulture, while also providing unique insights into a novel practice. Using a semi-structured interview and survey, we interviewed fifteen farmers representing 5% of total New Zealand wine production to examine ecological and economic benefits of sheep integration in viticulture systems. We find that seasonal integration of sheep during vine dormancy is common, while integration during the growing season is rare. Overall, farmers perceive significantly more benefits than challenges with the integration of sheep into vineyards, particularly reduced mowing (100% of farmers) and herbicide use (66% of farmers). On average, farmers reported 1.3 fewer herbicide applications annually, saving US$56 per hectare. As well, farmers indicated they were doing 2.2 fewer mows annually saving US$64 per hectare. These results suggest that wide-scale adoption of seasonal integration of sheep and viticulture can provide large ecological benefits and higher profitability vis-à-vis conventional viticulture practices; however, further integration of the two systems may provide even greater benefits not currently realized.
    Print ISSN: 1774-0746
    Electronic ISSN: 1773-0155
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 85
    facet.materialart.
    Unknown
    Springer
    Publication Date: 2018-03-06
    Description: We show how to select an item with the majority color from n two-colored items, given access to the items only through an oracle that returns the discrepancy of subsets of k items (the absolute value of the difference between the numbers of items with each color). We use \(n/\lfloor \tfrac{k}{2}\rfloor +O(k)\) queries, improving a previous method by De Marco and Kranakis that used \(n-k+k^2/2\) queries. We also prove a lower bound of \(n/(k-1)-O (n^{1/3})\) on the number of queries needed, both for discrepancy queries and to queries that return the partition of items into monochromatic subsets. This improves a lower bound of \(\lfloor n/k\rfloor \) by De Marco and Kranakis.
    Print ISSN: 0178-4617
    Electronic ISSN: 1432-0541