bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrical percolation behavior and electromagnetic shielding effectiveness of polyimide nanocomposites filled with carbon nanofibers
Authors: Nayak Lalatendu , Chaki Tapan K. , Khastgir Dipak 
Published: May 2014

ABSTRACTThe objective of present study is to prepare conductive polyimide (PI)–carbon nanofibers (CNFs) composite at very low percolation threshold. The combined advantage of in situ polymerization of PI in the presence of highly graphitized CNFs and continuous probe type sonication throughout the polymerization provide electrically conductive PI composites with a significantly lower percolation threshold than previously reported. The electrical conductivity and electromagnetic interference shielding effectiveness (EMI SE) of the nanocomposite with different weight percentages of CNFs (0.25–5 wt %) were investigated at room temperature. The measurement of EMI SE was carried out using thin film of composites in a frequency range of 8.2–12.4 GHz (X‐band). The direct current conductivity of composites follows the percolation scaling law with a very low percolation threshold (CNF, 0.5 wt %). The electrical conductivity of the PI composite increases by more than 10 decades of magnitude, from 5.8 × 10−16 to 2.03 × 10−6 mho cm−1 owing to the addition of 0.5 wt % of CNF. An increase in dielectric permittivity and decrease in alternating current impedance with increasing concentration of CNF are observed. The conduction mechanism in composites is explained in the light of power law‐dependent current (I)–voltage (V) characteristics. The composite of 0.07‐mm thickness shows EMI SE of above 12 decibel (dB) at 5 wt % of CNF loading. The experimental data suggest that the prepared composites can be used for the dissipation of electrostatic charge and EMI shielding purpose. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40914.
SPC methods for nonstationary correlated count data with application to network surveillance
Authors: Fu Yingzhuo , Jeske Daniel R. 
Published: May 2014

AbstractNetwork surveillance methods are becoming increasingly important as the ability to monitor a wide variety of data is rapidly expanding. Network traffic metrics are usually correlated count data that display a nonstationary pattern in their mean structures. We propose to model traffic counts using a generalized linear mixed model to capture these features. We then develop three tracking statistics proposed for anomaly detection. Two of the statistics are derived variants of a Bartlett‐type likelihood ratio, which itself is not computationally tractable. The first of these variants is based on an approximation to the integrated likelihood while the second is based on the concept of h‐likelihood. We also consider a tracking statistic that is an exponentially weighted moving average. We compare the properties of the three tracking statistics from the point of view of FAR and detection power and contrast the proposed tracking statistics with current literature. Our comparisons show that the two generalized likelihood ratio variants are preferred choices as statistical process control tools for network surveillance. Computational aspects of the three procedures are also discussed. While our application focus is network surveillance, our proposed methods apply to other applications that have similar data characteristics. Copyright © 2014 John Wiley & Sons, Ltd.
Characterization and cancer cell targeted imaging properties of human antivascular endothelial growth factor monoclonal antibody conjugated CdTe/ZnS quantum dots
Authors: Pang Lili , Xu Jian , Shu Chang , Guo Jin , Ma Xiaona , Liu Yu , Zhong Wenying 
Published: May 2014

ABSTRACTHigh luminescence quantum yield water‐soluble CdTe/ZnS core/shell quantum dots (QDs) stabilized with thioglycolic acid were synthesized. QDs were chemically coupled to fully humanized antivascular endothelial growth factor165 monoclonal antibodies to produce fluorescent probes. These probes can be used to assay the biological affinity of the antibody. The properties of QDs conjugated to an antibody were characterized by ultraviolet and visible spectrophotometry, fluorescent spectrophotometry, sodium dodecyl sulfate–polyacrylamide gel electrophoresis, transmission electron microscopy and fluorescence microscopy. Cell‐targeted imaging was performed in human breast cancer cell lines. The cytotoxicity of bare QDs and fluorescent probes was evaluated in the MCF‐7 cells with an MTT viability assay. The results proved that CdTe/ZnS QD–monoclonal antibody nanoprobes had been successfully prepared with excellent spectral properties in target detections. Surface modification by ZnS shell could mitigate the cytotoxicity of cadmium‐based QDs. The therapeutic effects of antivascular endothelial growth factor antibodies towards cultured human cancer cells were confirmed by MTT assay. Copyright © 2014 John Wiley & Sons, Ltd.
Influence of body mass index on mortality after surgery for perforated peptic ulcer
Authors: Buck D L , Møller M H 
Published: May 2014

Abstract

Background
Body mass index (BMI) is a strong predictor of mortality in the general population. In spite of the medical hazards of obesity, a protective effect on mortality has been suggested in surgical patients: the obesity paradox. The aim of the present nationwide cohort study was to examine the association between BMI and mortality in patients treated surgically for perforated peptic ulcer (PPU).

Methods
This was a national prospective cohort study of all Danish patients treated surgically for PPU between 1 February 2003 and 31 August 2009, for whom BMI was registered. Non-surgically treated patients and those with malignant ulcers were excluded. The primary outcome measure was 90-day mortality. The association between BMI and mortality was calculated as crude and adjusted relative risks (RRs) with 95 per cent confidence intervals (c.i.).

Results
Of 2668 patients who underwent surgical treatment for PPU, 1699 (63·7 per cent) had BMI recorded. Median age was 69·4 (range 17·6–100·9) years and 53·7 per cent of the patients were women. Some 1126 patients (66·3 per cent) had at least one of six co-morbid diseases; 728 (42·8 per cent) had an American Society of Anesthesiologists grade of III or more. A total of 471 patients (27·7 per cent) died within 90 days of surgery. Being underweight was associated with a more than twofold increased risk of death following surgery for PPU (adjusted RR 2·26, 95 per cent c.i. 1·37 to 3·71). No statistically significant association was found between obesity and mortality.

Conclusion
Being underweight was associated with increased mortality in patients with PPU, whereas being overweight or obese was neither protective nor an adverse prognostic factor.
Trends in surgery for screen-detected and interval breast cancers in a national screening programme
Authors: Nederend J , Duijm L E M , Louwman M W J , Roumen R M H , Jansen F H , Voogd A C 
Published: May 2014

Abstract

Background
This population-based study aimed to evaluate trends in surgical approach for screen-detected cancer versus interval breast cancer, and to determine the factors associated with positive resection margins.

Methods
Screening mammograms of women aged 50–75 years, who underwent biennial screening in a Dutch breast-screening region between 1997 and 2011, were included. Patient and tumour characteristics were compared between women who underwent mastectomy or breast-conserving surgery (BCS) for screen-detected or interval cancer, and women with a negative or positive resection margin after BCS.

Results
Some 417 013 consecutive screening mammograms were included. A total of 2224 screen-detected and 825 interval cancers were diagnosed. The BCS rate remained stable (mean 6·1 per 1000 screened women; P = 0·099), whereas mastectomy rates increased significantly during the study from 0·9 (1997–1998) to 1·9 (2009–2010) per 1000 screened women (P &lt; 0·001). The proportion of positive resection margins for invasive cancer was 19·6 and 7·6 per cent in 1997–1998 and 2009–2010 respectively (P &lt; 0·001), with significant variation between hospitals. Dense breasts, preoperative magnetic resonance imaging, microcalcifications, architectural distortion, tumour size over 20 mm, axillary lymph node metastasis and treating hospital were independent risk factors for mastectomy. Interval cancer, image-guided tumour localization, microcalcifications, breast parenchyma asymmetry, tumour size greater than 20 mm, lobular tumour histology, low tumour grade, extensive invasive component and treating hospital were independent risk factors for positive resection margins.

Conclusion
Mastectomy rates doubled during a 14-year period of screening mammography and the proportion of positive resection margins decreased, with variation among hospitals. The latter observation stresses the importance of quality control programmes for hospitals treating women with breast cancer.
Screening of allergic components mediated by H1R in homoharringtonine injection through H1R/CMC‐HPLC/MS
Authors: Guo Ying , Han Shengli , Cao Jingjing , Liu Qi , Zhang Tao 
Published: May 2014

ABSTRACTIt has been reported that the histamine H1 receptor (H1R) gene is up‐regulated in patients with allergic rhinitis and H1R expression level strongly correlates with the severity of allergy symptoms. Drugs for therapy should avoid allergy symptoms, especially for patients with over‐expressed H1R. Therefore, screening of the components which could induce H1R activation is urgently needed for drug safety evaluation. Homoharringtonine injection is a preparation for acute nonlymphocytic leukemia, which is approved by China Food and Drug Administration (CFDA) and US Food and Drug Administration. However, severely adverse reactions often occur with intravenous injection of the preparation. In present study, an H1R/CMC model was applied for capturing membrane retained components which could induce H1R activation. Retention components were enriched and analyzed by H1R/CMC‐HPLC/MS. Homoharringtonine was recognized, separated and identified in homoharringtonine injection. Ca2+ flux assay and p‐IP3R expression founded that homoharringtonine retained by the H1R/CMC model increased phosphorylation of IP3R and promoted cytosolic free Ca2+ elevation in a dose‐dependent manner which further verified the activity of homoharringtonine in activating the H1R. In conclusion, homoharringtonine was screened and identified as a potential allergic factor. This provides an indication that a patient with over‐expressed H1R should be aware of possible allergic reaction when applying homoharringtonine injection. Copyright © 2014 John Wiley & Sons, Ltd.
An LC‐MS/MS method for the simultaneous determination and pharmacokinetic studies of bergenin, chlorogenic acid and four flavonoids in rat plasma after oral administration of a QingGanSanJie decotion extract
Authors: Zhao Liang , Qian Xian , Li Wuhong , Lv Lei , Zhang Hai , Chai Yifeng , Zhang Guoqing 
Published: May 2014

ABSTRACTA rapid, simple and sensitive, liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method was developed and validated for simultaneous determination of bergenin, chlorogenic acid and four flavonoids in a QingGanSanJie preparation in rat plasma. Puerarin was selected as the internal standard (IS). Plasma samples were precipitated with methanol and separated with a reverse phase Agilent Poroshell 120 EC‐C18 column using a gradient mobile phase of methanol–water containing 0.1% formic acid (v/v). A triple quadruple mass spectrometer was used for quantification (limit of detection 0.36–5.55 ng/mL). Intra‐day and inter‐day precisions were within 15% and the average extraction recoveries ranged from 85 to 115% for each analyte. The method allowed simultaneous quantification for the first time of the pharmacokinetics of bergenin, chlorogenic acid and four flavonoids after intragastric administration of a QingGanSanJie extract in Sprague–Dawley rats. It was found that bergenin and chlorogenic acid had typical extravascular administration concentration–time curves; flavonoids had a bimodal distribution improving bioavailability and extending the pharmacodynamics period. Copyright © 2014 John Wiley & Sons, Ltd.
Liquid chromatography mass spectrometry simultaneous determination of vindoline and catharanthine in rat plasma and its application to a pharmacokinetic study
Authors: Lin Chongliang , Cai Jinzhang , Yang Xuezhi , Hu Lufeng , Lin Guanyang 
Published: May 2014

ABSTRACTVinblastine and vincristine, both of which are bisindole alkaloids derived from vindoline and catharanthine, have been used for cancer chemotherapy; their monomeric precursor molecules are vindoline and catharanthine. A simple and selective liquid chromatography mass spectrometry method for simultaneous determination of vindoline and catharanthine in rat plasma was developed. Chromatographic separation was achieved on a C18 (2.1 × 50 mm, 3.5 µm) column with acetonitrile–0.1% formic acid in water as mobile phase with gradient elution. The flow rate was set at 0.4 mL/min. An electrospray ionization source was applied and operated in positive ion mode; selective ion monitoring mode was used for quantification. Mean recoveries were in the range of 87.3–92.6% for vindoline in rat plasma and 88.5–96.5% for catharanthine. Matrix effects for vindoline and catharanthine were measured to be between 95.3 and 104.7%. Coefficients of variation of intra‐day and inter‐day precision were both <15%. The accuracy of the method ranged from 93.8 to 108.1%. The method was successfully applied in a pharmacokinetic study of vindoline and catharanthine in rats. The bioavailability of vindoline and catharanthine were 5.4 and 4.7%, respectively. Copyright © 2014 John Wiley & Sons, Ltd.
Real‐time depth‐of‐field rendering using single‐layer composition
Authors: Fang Xiaoxin , Sheng Bin , Wu Wen , Fan Zengzhi , Ma Lizhuang 
Published: May 2014

ABSTRACTIn this paper, we propose a single‐layer post‐processing method for real‐time depth‐of‐field rendering that uses single‐layer composition. In the proposed method, blurring is achieved by gathering background pixels and scattering foreground pixels. Major artifacts in post‐filtering techniques such as intensity leakage and blurring discontinuity are reduced by using two different blurring functions and the controllable parameter in the gathering process. The method can be entirely implemented in GPU parallelization to achieve the real‐time performance required for virtual reality. The results of comparisons of our method with recent post‐processing methods in terms of rendering quality and rendering performance indicate that our method generates realistic natural images and is also the fastest in terms of frames per second. Copyright © 2014 John Wiley & Sons, Ltd.
Understanding Photochirogenesis: Solvent Effects on Circular Dichroism and Anisotropy Spectroscopy
Authors: Bredehöft Jan Hendrik , Jones Nykola C. , Meinert Cornelia , Evans Amanda C. , Hoffmann Søren V. , Meierhenrich Uwe J. 
Published: May 2014

ABSTRACTThe basic units that constitute essential biopolymers (proteins and nucleic acids) are enantiomerically biased. Proteins are constructed from L‐amino acids and nucleic acids possess a backbone composed exclusively of D‐sugars. Photochirogenesis has been postulated to be the source of this homochirality of biomolecules: Asymmetric photochemical reactions were catalyzed by circularly polarized light (cpl) in interstellar environments and generated the first chiral prebiotic precursors. Enantiomers absorb cpl differently and this difference can dictate the kinetics of asymmetric photochemical reactions. These differences in absorption can be studied using circular dichroism (CD) and anisotropy spectroscopy. Rather than measuring the CD spectrum alone, the anisotropy factor g is recorded (CD divided by absorption). This factor g is directly related to the maximum achievable enantiomeric excess. We now report on the substantial influence of solvent and molecular surroundings on CD and anisotropy spectroscopy. This shows for the first time that CD and anisotropy signals depend just as much on the molecular surroundings of a molecule as on the nature of the molecule itself. CD and g spectra of amino acids in different solvents and in the solid state are presented here and the influence of these different surroundings on the spectra is discussed. Chirality 26:373–378, 2014. © 2014 Wiley Periodicals, Inc.
The impact of significant input of fine sediment on benthic fauna at tributary junctions: a case study of the Bermejo–Paraguay River confluence, Argentina
Authors: Blettler Martín C. M. , Amsler Mario L. , Ezcurra de Drago Inés , Espinola Luis A. , Eberle Eliana , Paira Aldo , Best James L. , Parsons Daniel R. , Drago Edmundo E. 
Published: May 2014

AbstractThis study examines the morphological features, suspended sediment inputs and hydraulic conditions within a large river in association with ecological patterns before and after a tributary confluence. In order to examine these effects, the macroinvertebrate distributions from three reaches of the Paraguay and Bermejo Rivers (Paraguay–Argentina) are investigated. The Bermejo River is a tributary that supplies significant quantities of fine sediment to the Paraguay River, primarily in suspension. Two reaches were examined on the Paraguay River, upstream and downstream of the Bermejo River junction, with the third study reach located on the Bermejo River, upstream of the confluence with the Paraguay River. The results provide clear evidence that a significantly increased loading of fine sediment at a river confluence has effects on the distribution and potential movement of benthic invertebrates in the lotic environment by representing physical barriers at affected sites. These effects may be important at both local and regional scales, and such increases in suspended sediment (especially associated with anthropogenic change) may thus pose a major threat to ecosystem integrity that has been historically underestimated. Copyright © 2014 John Wiley & Sons, Ltd.
Gamma delta T cells in non‐immune patients during primary schistosomal infection
Authors: Schwartz Eli , Rosenthal Etti , Bank Ilan 
Published: May 2014

AbstractThe mevalonate pathway is critical for the survival of Schistosoma. γδ T cells, a small subset of peripheral blood (PB) T cells, recognize low molecular weight phosphorylated antigens in the mevalonate pathway, which drive their expansion to exert protective and immunoregulatory effects. To evaluate their role in schistosomiasis, we measured γδ T cells in the PB of non‐immune travelers who contracted Schistosoma hematobium or Schistosoma mansoni in Africa. The maximal level of γδ T‐cells following infection was 5.78 ± 2.19% of the total T cells, versus 3.72 ± 3.15% in 16 healthy controls [P = 0.09] with no difference between S. hematobium and S. mansoni in this regard. However, among the nine patients in the cohort who presented with acute schistosomiasis syndrome (AS), the level (3.5 ± 1.9%) was significantly lower than in those who did not (8.6 ± 6.4%, P < 0.05), both before and after therapy. Furthermore, γδ T cells increased significantly in response to praziquantel therapy. In a patient with marked expansion of γδ T cells, most expressed the Vδ2 gene segment, a hallmark of cells responding to cognate antigens in the mevalonate pathways of the parasite or the human host. These results suggest an immunoregulatory role of antigen responsive γδ T cells in the clinical manifestations of early schistosomal infection.
MIXED‐FREQUENCY STRUCTURAL MODELS: IDENTIFICATION, ESTIMATION, AND POLICY ANALYSIS
Authors: Foroni Claudia , Marcellino Massimiliano 
Published: May 2014

SUMMARYThe mismatch between the timescale of DSGE (dynamic stochastic general equilibrium) models and the data used in their estimation translates into identification problems, estimation bias, and distortions in policy analysis. We propose an estimation strategy based on mixed‐frequency data to alleviate these shortcomings. The virtues of our approach are explored for two monetary policy models. Copyright © 2014 John Wiley & Sons, Ltd.
Enhancement of adhesion and promotion of osteogenic differentiation of human adipose stem cells by poled electroactive poly(vinylidene fluoride)
Authors: Pärssinen Jenita , Hammarén Henrik , Rahikainen Rolle , Sencadas Vitor , Ribeiro Clarisse , Vanhatupa Sari , Miettinen Susanna , Lanceros‐Méndez Senentxu , Hytönen Vesa P. 
Published: May 2014

AbstractPoly(vinylidene fluoride) (PVDF) is a biocompatible material with excellent electroactive properties. Nonelectroactive α‐PVDF and electroactive β‐PVDF were used to investigate the substrate polarization and polarity influence on the focal adhesion (FA) size and number as well as on human adipose stem cells (hASCs) differentiation. hASCs were cultured on different PVDF surfaces adsorbed with fibronectin and FA size and number, total adhesion area, cell size, cell aspect ratio and FA density were estimated using cells expressing vinculin fused to enhanced green fluorescent protein. Osteogenic differentiation was also determined using a quantitative alkaline phosphatase assay. The surface charge of the poled PVDF films (positive or negative) influenced the hydrophobicity of the samples, leading to variations in the conformation of adsorbed extracellular matrix proteins, which ultimately modulated the stem cell adhesion on the films and induced their osteogenic differentiation. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 919–928, 2015.
Facile synthesis and in situ magnetization of carbon‐decorated lignocellulose fiber for highly efficient removal of methylene blue
Authors: Li Meng , Wang Shi , Luo Wenjun , Xia Hua , Gao Qiang , Zhou Chenggang 
Published: May 2014

ABSTRACTBACKGROUNDMagnetic adsorption is currently a popular way to remove chemical pollutants from water. The present work reported highly efficient removal of methylene blue (MB) by magnetically retrievable carbon‐decorated lignocellulose fiber (mC@LCF).RESULTSCarbon‐decorated lignocellulose fiber (C@LCF) was successfully synthesized via the hydrothermal carbonization process using a low‐cost and environment‐friendly lignocellulose fiber (LCF) as raw material. Further, the C@LCF was in situ magnetized by simply adding it and magnetic nanoparticle (MNP) into methylene blue (MB) solution taking advantage of the spontaneous behavior of MNP adherence to the surface of C@LCF. During this period, MB was efficiently removed, and the maximum removal capacity was 232.3 mg g−1 at 303.15 K. Kinetic and thermodynamic investigations as well as isotherm analysis were also undertaken. Reusability of mC@LCF was evaluated, and results showed that removal of MB exceeded 90% after seven consecutive cycles.CONCLUSIONSThe mC@LCF has obvious advantages including ease of production, low production costs, environmental friendliness, magnetic retrievability, and high efficiency for MB adsorption. Thus mC@LCF is a promising adsorbent for the purification of dye‐containing wastewater. © 2014 Society of Chemical Industry