bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, characterization, and Pb2+ ion sensing application of hexa‐armed dansyl end‐capped poly(ε‐caprolactone) star polymer with phosphazene core
Authors: Gorur Mesut , Doganci Erdinc , Yilmaz Faruk , Isci Umit 
Published: May 2015

ABSTRACTNovel hexa‐armed dansyl end‐capped poly(ε‐caprolactone) (PCL) star polymer with phosphazene core (P2) was prepared via ring opening polymerization (ROP) and esterification reactions. P2 showed dual fluorescence emission when excited at 328 nm in acetonitrile : water (6 : 4) due to twisted intramolecular charge transfer (TICT) between dimethylamino and naphthalene units in the dansyl moiety. TICT emission band (A band) in the emission spectra red‐shifted with increasing solvent polarity. P2 responded to the addition of Pb2+, Hg2+, Co2+, Cd2+, Mn2+, and Zn2+ metal ions by decreasing TICT emission band with slight bathochromic shifts. The highest quenching efficiency was observed for Pb2+ ion with Stern–Volmer constant of 324.74M−1. The Stern–Volmer plot for Pb2+ was rather linear with the increasing concentration of the quencher, indicating a dynamic (collisional) quenching mechanism. Stern–Volmer constants for Hg2+, Co2+, Cd2+, Mn2+, and Zn2+ ions were found to be 212.33, 189.21, 36.24, 20.84, and 20.69, respectively. Besides, the highest quenching efficiency (94.24%) was attained in the presence of Pb2+, suggesting that P2 could be employed as a potential Pb2+ chemical probe. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42380.
Modification of surface properties of wool fabric with linde type a nano‐zeolite
Authors: Carran Richard S. , Ghosh Arun , Dyer Jolon M. 
Published: May 2015

ABSTRACTWool is a naturally occurring composite fiber consisting of keratin and keratin‐associated proteins as the key molecular components. The outermost surface of wool comprises a lipid layer that renders the surface hydrophobic, which hinders certain fabric processing steps and moisture management properties of wool fabrics. In this study, Linde Type A (LTA) nano‐zeolite (a Na+‐, Ca2+‐, and K+‐exchanged type A zeolite) was integrated onto the surface of wool using 3‐mercaptopropyl trimethoxy silane as a bridging agent. The resultant surface morphology, hydrophilicity, and mechanical performance of the treated wool fabrics were evaluated. Notably, the surface hydrophilicity of wool increased dramatically. When wool was treated with a dispersion of 1 wt % zeolite and 0.2 wt % silane, the water contact angle decreased from an average value of 148° to 50° over a period of approximately 5 min. Scanning electron microscopic imaging indicated good coverage of the wool surface with zeolite particles, and infrared spectroscopic evaluation demonstrated strong bonding of the zeolite to wool keratins. The zeolite application showed no adverse effects on the tensile and other mechanical properties of the fabric. This study indicates that zeolite‐based treatment is potentially an efficient approach to increasing the surface hydrophilicity and modifying other key surface properties such as softness of wool and wool fabrics. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42392.
Poly(ethylene oxide)‐g‐gellan polysaccharide nanocarriers for controlled gastrointestinal delivery of simvastatin
Authors: Sadhukhan Sayantan , Bakshi Paromita , Datta Rana , Maiti Sabyasachi 
Published: May 2015

ABSTRACTHerein, a novel gellan polysaccharide‐based amphiphilic copolymer was synthesized for the development of simvastatin‐loaded micellar nanoparticles. The nanoparticles were explored for their controlled drug release and improved pharmacodynamic potentials. The copolymer was characterized by Fourier transform infrared spectroscopy (FTIR) and elemental analysis. The onset of copolymer micellization was detected by fluorescence spectroscopy. Simvastatin was loaded into micellar particles by solvent evaporation method and the particles were then characterized by microscopic and light scattering techniques. The physical state of drug was studied by X‐ray diffraction analysis. Pharmacodynamic assessment of the micellar preparations was done on rabbit models. The copolymer formed micellar nanoparticles in water. Critical micellar concentration was 9.12mg/l. The micellar particles (426.8–912.6nm) entrapped a maximum of 18.86% drug. Higher negative zeta potential indicated physical stability of micellar systems. A simple diffusion mechanism was operative in the event of comparatively faster drug release in pH6.8 phosphate buffer solution. No significant drug‐copolymer interaction was traced by FTIR spectroscopy. The amorphization of drug into micellar particles reduced LDL‐cholesterol level by ∼45% in hyperlipidemic rabbits and this was about 2.5 times higher than pure drug dispersion. Copolymer micellar nanoparticles of simvastatin could control cholesterol level in hyperlipidemic rabbits and thus had potential in drug delivery applications. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42399.
Effects of raw and poly(propylene oxide) grafted nanosilica on the morphology and thermal and mechanical properties of polyurethane foam
Authors: Gao Xia , Chen Keping , Liang Shuen , Fan Chunchun , Huang Yigang , Jia Xiaorong , Tian Chunrong , Wang Jianhua 
Published: May 2015

ABSTRACTPoly(propylene oxide) (PPO)‐grafted nanosilica (NS)/polyurethane foam (PUF) composites were synthesized by a ring‐opening polymerization catalytic process and reaction‐molding technology. The raw NS and PPO–NS were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and transmission electron microscopy. Scanning electron microscopy, dynamic mechanical analysis, and compressive strength tests were used to compare the morphology and thermal and mechanical properties of the PPO–NS/PUF and raw NS/PUF composites with a series of filler contents. The PPO–NS/PUF composites generally exhibited better morphology, thermal and mechanical properties than raw NS/PUF composites. Moreover, the PPO–NS/PUF composites with lower contents (0.5, 1 php) of filler showed even higher mechanical reinforcement than that with higher contents (1.5, 2 php) of filler, which was caused by the interaction between additives and PUF matrix. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42400.
Characterization of intrinsic variability in time‐series metabolomic data of cultured mammalian cells
Authors: Le Huong , Jerums Matthew , Goudar Chetan T. 
Published: May 2015

ABSTRACTIn an attempt to rigorously characterize the intrinsic variability associated with Chinese Hamster Ovary (CHO) cell metabolomics studies, supernatant and intracellular samples taken at 5 time points from duplicate lab‐scale bioreactors were analyzed using a combination of gas chromatography (GC)‐ and liquid chromatography–mass spectrometry (LC–MS) based metabolomics. The intrinsic variability between them was quantified using the relative standard deviation (RSD), and the median RSD was 9.4% and 12.4% for supernatant and intracellular samples, respectively. When exploring metabolic changes between lab‐ and pilot‐scale bioreactors, a high number of metabolites (65–105) were significantly different when no corrections were made for this intrinsic variability. This distinction also extended to principal component and metabolic pathway analysis. However, when intrinsic variability was taken into account, the number of metabolite with significant changes reduced substantially (20–25) as did the separation in principal component and metabolic pathway analysis, suggesting a much smaller change in physiology across bioreactor scale. Our results also suggested the contribution of biological variability to the total variability across replicates (∼0.4%) was significantly lower than that from technical variability (∼9–12%). Our study highlights the need for understanding and accounting for intrinsic variability in CHO cell metabolomics studies. Failure to do so can result in incorrect biological interpretation of the observations which could ultimately lead to the identification of a suboptimal set of targets for genetic engineering or process development considerations. Biotechnol. Bioeng. 2015;112: 2276–2283. © 2015 Wiley Periodicals, Inc.
A comparative study on volatile metabolites profile of Dracaena cochinchinensis (Lour.) S.C. Chen xylem with and without resin using GC‐MS
Authors: Teng Zhongqiu , Zhang Mei , Meng Shiying , Dai Rongji , Meng Weiwei , Deng Yulin , Huang Luqi 
Published: May 2015

AbstractDragon's blood is a famous traditional Chinese medicine produced from source plants under bio‐ or abio‐stress. Dracaena cochinchinensis (Lour.) S.C. Chen xylem (DX) is one of the most important sources of the medicine. In this work, a GC‐MS method was developed for analysis of the n‐hexane extracts of DX with resin (DXR) and without resin (DXW). The repeatability of the method was also investigated for a metabolite comparative study of the different xylems. About 80 components were detected, 26 of which were identified in both DXR and DXN. Three sesquiterpenes (τ‐cadinol, τ‐muurolon and α‐cadinol) were first discovered in Dracaena cochinchinensis (Lour.) S.C. Chen. The chromatographs of the two plant materials were compared and differences of compounds were found. It showed that phytosterols showed a dramatic rise in content, and sesquiterpenes were found to be synthesized in DXR. Copyright © 2015 John Wiley & Sons, Ltd.
Immobilizing Systems Biocatalysis for the Selective Oxidation of Glycerol Coupled to In Situ Cofactor Recycling and Hydrogen Peroxide Elimination
Authors: Rocha‐Martin Javier , Acosta Andreína , Guisan Jose M. , López‐Gallego Fernando 
Published: May 2015

AbstractThe combination of three different enzymes immobilized rationally on the same heterofunctional carrier allowed the selective oxidation of glycerol to 1,3‐dihydroxyacetone (DHA) coupled to in situ redox‐cofactor recycling and H2O2 elimination. In this cascade, engineered glycerol dehydrogenase with reduced product inhibition oxidized glycerol selectively to DHA with the concomitant reduction of NAD+ to NADH. NADH oxidase regenerated the NAD+ pool by oxidizing NADH to NAD+ to form H2O2 as the byproduct. Finally, catalase eliminated H2O2 to yield water and O2 as innocuous products, which avoided the spontaneous DHA oxidation triggered by H2O2. The co‐immobilization of the three enzymes on the same porous carrier allowed the in situ recycling and disproportionation of the redox cofactor and H2O2, respectively, to produce up to 9.5 mM DHA, which is 18‐ and 6‐fold higher than glycerol dehydrogenase itself and a soluble multienzyme system, respectively.
Increased Transforming Growth Factor‐β Levels Associated With Cardiac Adverse Events in Hypertrophic Cardiomyopathy
Authors: Ayça Burak , Sahin Irfan , Kucuk Suat Hayri , Akin Fatih , Kafadar Didem , Avşar Murat , Avci Ilker Ilhan , Gungor Barış , Okuyan Ertugrul , Dinckal Mustafa Hakan 
Published: May 2015

ABSTRACTBackgroundHypertrophic cardiomyopathy (HCM) is a common genetic heart disease characterized by ventricular hypertrophy, myocardial fibrosis, and impaired ventricular relaxation. The exact mechanisms by which fibrosis is caused remain unknown.HypothesisCirculating TGF‐β is related to poor prognosis in HCM.MethodsWe compared TGF‐β levels of 49 HCM patients with those of 40 non‐HCM patients. We followed the patients with HCM for 18 months and divided them into 2 groups: low TGF‐β (≤4877 pg/mL) and high TGF‐β (>4877 pg/mL). We compared the 2 groups in terms of brain natriuretic peptide (BNP), echocardiographic parameters, and clinical outcomes including myocardial infarction, arrhythmias, implantable cardioverter‐defibrillator implantation, hospitalization, New York Heart Association (NYHA) class, acute heart failure, and mortality.ResultsThe HCM patients had higher TGF‐β levels than those in the control group (P = 0.005). In the follow‐up, those in the high TGF‐β group had higher BNP levels, larger left‐atrial size, thicker interventricular septum, NYHA class, more hospitalizations, and a greater number of clinical adverse events (P < 0.001, P = 0.01, P < 0.001, P = 0.002, P < 0.001 and P = 0.003, respectively). TGF‐β level of >4877 pg/mL can predict adverse events with a specificity of 75% and a sensitivity of 72% (P = 0.014). In multivariate regression analysis, TGF‐β, BNP, and interventricular septum thickness were significantly associated with adverse events (P = 0.028, P = 0.030, and P = 0.034, respectively).ConclusionsThe TGF‐β level is higher in HCM patients and associated with a poor prognosis in HCM.
Male‐female patient differences in the association between end‐of‐life discussions and receipt of intensive care near death
Authors: Sharma Rashmi K. , Prigerson Holly G. , Penedo Frank J. , Maciejewski Paul K. 
Published: May 2015

BACKGROUNDPatient gender plays a significant role in patient‐physician communication, patients’ understanding of illness, and the aggressiveness of end‐of‐life (EoL) care. However, little is known about the extent to which gender differences in the effects of EoL discussions on EoL care contribute to gender differences in EoL care. The current study was aimed at determining whether gender differences exist in the receipt of intensive care unit (ICU) care near death and in the association between EoL discussions and the receipt of EoL ICU care.METHODSThis was a multisite, prospective cohort study of patients (n = 353) with metastatic cancers who were identified as terminally ill at study enrollment and were interviewed at a median of 4.1 months before their deaths. Postmortem chart reviews and caregiver interviews documented ICU stays in the last week of life.RESULTSPatients who received ICU care at the EoL were more likely to be male than those who did not (73% vs 52%, P = .02). After adjustments for potential confounders, male patients reporting an EoL discussion were less likely to have an ICU stay in the last week of life than male patients with no EoL discussion (adjusted odds ratio, 0.26, 95% confidence interval, 0.07‐0.91; P = .04). There was no association between EoL discussions and ICU stays near death among female patients.CONCLUSIONSMen with advanced cancers are more likely than women to receive aggressive, nonbeneficial ICU care near death. Gender differences in the effects of EoL discussions on EoL care likely contribute to and may even explain gender differences in the receipt of ICU care in the last week of life. Cancer 2015;121:2814‐2820. © 2015 American Cancer Society
Detection of minimal residual disease in B lymphoblastic leukemia using viSNE
Authors: DiGiuseppe Joseph A. , Tadmor Michelle D. , Pe'er Dana 
Published: May 2015

BackgroundMinimal residual disease (MRD) following treatment is a robust prognostic marker in B lymphoblastic leukemia. However, the detection of MRD by flow cytometric immunophenotyping is technically challenging, and an automated method to detect MRD is therefore desirable. viSNE, a recently developed computational tool based on the t‐Distributed Stochastic Neighbor Embedding (t‐SNE) algorithm, has been shown to be capable of detecting synthetic “MRD‐like” populations of leukemic cells created in vitro, but whether viSNE can facilitate the immunophenotypic detection of MRD in clinical samples has not been evaluated.MethodsWe applied viSNE retrospectively to 8‐color flow cytometric immunophenotyping data from normal bone marrow samples, and samples from B lymphoblastic leukemia patients with or without suspected MRD on the basis of conventional manual gating.ResultsIn each of 14 bone marrow specimens containing MRD or suspected MRD, viSNE identified a putative MRD population; an abnormal composite immunophenotype was confirmed for the putative MRD in each case. MRD populations were not identified by viSNE in control bone marrow samples from patients with increased normal B‐cell precursors, or in post‐treatment samples from B lymphoblastic leukemia patients who did not have detectable MRD by manual gating.ConclusionviSNE shows promise as an automated method to facilitate immunophenotypic MRD detection in patients treated for B lymphoblastic leukemia. © 2015 International Clinical Cytometry Society
Toward accurate molecular identification of species in complex environmental samples: testing the performance of sequence filtering and clustering methods
Authors: Flynn Jullien M. , Brown Emily A. , Chain Frédéric J. J. , MacIsaac Hugh J. , Cristescu Melania E. 
Published: May 2015

AbstractMetabarcoding has the potential to become a rapid, sensitive, and effective approach for identifying species in complex environmental samples. Accurate molecular identification of species depends on the ability to generate operational taxonomic units (OTUs) that correspond to biological species. Due to the sometimes enormous estimates of biodiversity using this method, there is a great need to test the efficacy of data analysis methods used to derive OTUs. Here, we evaluate the performance of various methods for clustering length variable 18S amplicons from complex samples into OTUs using a mock community and a natural community of zooplankton species. We compare analytic procedures consisting of a combination of (1) stringent and relaxed data filtering, (2) singleton sequences included and removed, (3) three commonly used clustering algorithms (mothur, UCLUST, and UPARSE), and (4) three methods of treating alignment gaps when calculating sequence divergence. Depending on the combination of methods used, the number of OTUs varied by nearly two orders of magnitude for the mock community (60–5068 OTUs) and three orders of magnitude for the natural community (22–22191 OTUs). The use of relaxed filtering and the inclusion of singletons greatly inflated OTU numbers without increasing the ability to recover species. Our results also suggest that the method used to treat gaps when calculating sequence divergence can have a great impact on the number of OTUs. Our findings are particularly relevant to studies that cover taxonomically diverse species and employ markers such as rRNA genes in which length variation is extensive.
4′‐O‐Methylnorbelladine feeding enhances galanthamine and lycorine production by Leucojum aestivum L. shoot cultures
Authors: Saliba Sahar , Ptak Agata , Laurain‐Mattar Dominique 
Published: May 2015

Galanthamine and lycorine are Amaryllidaceae alkaloids that exhibit a wide range of pharmacological activities. Organic synthesis and plant extraction are the two main commercial sources of galanthamine. Since total organic synthesis is low yielding and complex, and the harvesting of plant biomass is causing wild plant depletion, in vitro cultures offer an alternative approach. Amaryllidaceae alkaloids can be regarded as derivatives of the common precursor 4′‐O‐methylnorbelladine via intramolecular oxidative phenol coupling. The aim of this work was to enhance the biosynthetic pathway of these alkaloids using in vitro techniques. The precursor 4′‐O‐methylnorbelladine was incorporated into the liquid medium of Leucojum aestivum shoot cultures at different concentrations (0, 0.05, 0.1, or 0.2 g/L). The cultures were conducted for various periods of time (15, 30, and 40 days). After alkaloid extraction and according to LC‐ESI‐MS analysis, the precursor highly stimulated the biosynthesis of both galanthamine (0.5 mg/g dry weight [DW], V/S 0.01 mg/g DW in the control sample, i.e. without precursor) and lycorine (0.2 mg/g DW, V/S 0.04 mg/g DW in the control sample) after its biotransformation by the shoot cultures. The optimal culture conditions for the production of both alkaloids were 0.1 g/L of precursor and 15 days of culture.
Body‐related Sport and Exercise Motives and Disturbed Eating Attitudes and Behaviours in Adolescents
Authors: Maïano Christophe , Morin Alexandre J. S. , Lanfranchi Marie‐Christine , Therme Pierre 
Published: May 2015

AbstractMotives underlying sport and exercise involvement have recently been hypothesized as potential factors influencing the positive association between sports/exercises involvement and disturbed eating attitudes and behaviours (DEAB) among adolescents. Nevertheless, very few studies have examined this hypothesis or the moderating role of gender, context of practice, performance levels and sport type on these relationships. In this study, these questions were addressed among 168 male and 167 female French adolescents involved in various types, contexts and performance levels of sport and exercise. Participants were asked to indicate their main motives for involvement in sport practice and to self‐report DEAB (generic DEAB, vomiting–purging behaviours, and eating‐related control) on a French adaptation of the Eating Attitudes Test‐26. The results shared positive associations between body‐related sport and exercise motives and most of the DEAB subscales. Furthermore, they show that the relationship between body‐related sport and exercise motives and Vomiting–Purging Behaviours differs according to involvement in individual and competitive sports and exercises. Copyright ©2015 John Wiley & Sons, Ltd and Eating Disorders Association.
Performance analysis of spatial OFDM for pixelated optical wireless systems
Authors: Mondal M. Rubaiyat H. , Panta Kusha 
Published: May 2015

AbstractPixelated optical wireless systems can transmit at high speed by encoding data in transmitted images using spatial orthogonal frequency division multiplexing (spatial OFDM) but are susceptible to a number of limiting factors including defocus, linear fractional misalignment (LFM) and vignetting. This paper investigates the effects of these impairments on the performance of both forms of spatial OFDM: spatial DC‐biased optical OFDM (SDCO‐OFDM) and spatial asymmetrically clipped optical OFDM (SACO‐OFDM). The novelty of this paper is in the theoretical analysis of the effect of defocus on a spatial OFDM based pixelated system. The theoretical results for defocus are found to be in agreement with the simulation results reported in the literature. Furthermore, the joint effects of defocus, LFM and vignetting are mathematically described. Analytical and simulation results show that these three factors are largely independent of each other. Simulation results indicate that these impairments and their associated mitigation techniques influence the optimum choice of DC bias for SDCO‐OFDM. Finally, it is shown that for the case of the joint impairments and for a given data rate, the bit error rate performance of SDCO‐OFDM with the optimum bias is slightly better than that of SACO‐OFDM. Copyright © 2015 John Wiley & Sons, Ltd.
A hybrid kinetic WENO scheme for inviscid and viscous flows
Authors: Liu Hongwei 
Published: May 2015

SummaryIn this paper, we propose a high‐order finite volume hybrid kinetic Weighted Essentially Non‐Oscillatory (WENO) scheme for inviscid and viscous flows. Based on the WENO reconstruction technique, a hybrid kinetic numerical flux is introduced for the present method, which includes the mechanisms of both the free transfer and the collision of gas molecules. The collisionless free transfer part of the hybrid numerical flux is constructed from the conventional kinetic flux vector splitting treatment, and the collision contribution is considered by constructing an equilibrium gas state and calculating the corresponding numerical flux at the cell interface. The total variation diminishing Runge–Kutta methods are used for the temporal integration. The high‐order accuracy and good shock‐capturing capability of the proposed hybrid kinetic WENO scheme are validated by many numerical examples in one‐dimensional and two‐dimensional cases. Copyright © 2015 John Wiley & Sons, Ltd.