bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modification of structural, thermal, and electrical properties of PVA by addition of silicon carbide nanocrystals
Authors: Saini Isha , Sharma Annu , Rozra Jyoti , Dhiman Rajnish , Aggarwal Sanjeev , Sharma Pawan K. 
Published: May 2015

ABSTRACTSiC‐PVA nanocomposite films, synthesized using solution‐casting technique were structurally characterized using X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. Morphological studies of the SiC‐PVA nanocomposite films were carried out using Transmission electron microscopy (TEM) and Scanning electron microscopy (SEM). TEM analysis confirms that the size of SiC nanocrystals present in PVA matrix are 23 ± 9 nm, which is consistent with size calculated using XRD. SiC‐PVA nanocomposite films were further characterized for their thermal and electrical properties. Thermogravimetric/differential thermal analysis (TG/DTA) indicates that the char yield of nanocomposite films containing 3 wt % SiC nanocrystal is ∼30% more than PVA. This increase in char yield is an indication of the potency of flame retardation of SiC‐PVA nanocomposite films. I‐V analysis reveals that Schottky mechanism is the dominant conduction mechanism which is responsible for the increase in conductivity of PVA with the addition of SiC nanocrystals. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42464.
Tackling Substandard and Falsified Medicines in the Mekong: National Responses and Regional Prospects
Authors: Lamy Marie , Liverani Marco 
Published: May 2015

AbstractThe wide circulation of substandard medicines in Southeast Asia is a serious public health concern. Substandard medicines may contain none, or inadequate quantities of the active ingredient, or may contain harmful ingredients. This poses a considerable threat to human lives and an obstacle to infectious disease control at the national, regional and global level, also due to the associated risk of antimicrobial resistance. As trade liberalisation in the region intensifies, moreover, there are concerns that reduced custom controls and higher mobility of people and goods may increase the illicit trade in falsified medicines. In this context, crucial is the ability of governments to develop adequate regulations and capacities as well as enforcement measures to tackle these issues. Given the transnational nature of the problem, the establishment of effective mechanisms for cross‐country surveillance, information exchange and coordinated action is also necessary. In this article, we provide an overview of national responses, reflecting on strengths and limitations of past interventions. We then examine existing institutional frameworks for regional health cooperation, particularly the Association of Southeast Asian Nations, and their potential to support enhanced capacities and cooperation to address this challenge.
Effects of solvent polarity on the absorption and fluorescence spectra of chlorogenic acid and caffeic acid compounds: determination of the dipole moments
Authors: Belay Abebe , Libnedengel Ermias , Kim Hyung Kook , Hwang Yoon‐Hwae 
Published: May 2015

AbstractThe effects of solvent polarity on absorption and fluorescence spectra of biologically active compounds (chlorogenic acid (CGA) and caffeic acids (CA)) have been investigated. In both spectra pronounced solvatochromic effects were observed with shift of emission peaks larger than the corresponding UV‐vis electronic absorption spectra. From solvatochromic theory the ground and excited‐state dipole moments were determined experimentally and theoretically. The differences between the excited and ground state dipole moment determined by Bakhshiev, Kawski–Chamma–Viallet and Reichardt equations are quite similar. The ground and excited‐state dipole moments were determined by theoretical quantum chemical calculation using density function theory (DFT) method (Gaussian 09) and were also similar to the experimental results. The HOMO‐LUMO energy band gaps for CGA and CFA were calculated and found to be 4.1119 and 1.8732 eV respectively. The results also indicated the CGA molecule is more stable than that of CFA. It was also observed that in both compounds the excited state possesses a higher dipole moment than that of the ground state. This confirms that the excited state of the hydroxycinnamic compounds is more polarized than that of the ground state and therefore is more sensitive to the solvent. Copyright © 2015 John Wiley & Sons, Ltd.
Synthesis and photoluminescence characteristics of (Y,Gd)BO3:RE (RE = Eu3+, Ce3+, Dy3+ and Tb3+) phosphors for blue chip and near‐UV white LEDs
Authors: Rangari V. V. , Singh V. , Dhoble S. J. 
Published: May 2015

AbstractA series of Eu3+‐, Ce3+‐, Dy3+‐ and Tb3+‐doped (Y,Gd)BO3 phosphors was synthesized by a solid‐state diffusion method. X‐Ray diffraction confirmed their hexagonal structure and the scanning electron microscopy results showed crystalline particles. The excitation spectra revealed that (Y,Gd)BO3 phosphors doped with Eu3+, Ce3+ , Dy3+ and Tb3+ are effectively excited with near UV‐light of 395 nm/blue light, 364, 351 and 314 nm, respectively. Photoluminescence spectra of Eu3+‐, Ce3+‐ and Tb3+/Dy3+‐doped phosphor showed intense emission of reddish orange, blue and white light, respectively. The phosphor Y0.60Gd0.38BO3:Ce0.02 showed CIE 1931 color coordinates of (0.158, 0.031) and better color purity compared with commercially available blue BAM:Eu2+ phosphor. The phosphor (Y,Gd)BO3 doped with Eu3+, Dy3+ and Tb3+ showed CIE 1931 color coordinates of (0.667, 0.332), (0.251, 0.299) and (0.333, 0.391) respectively. Significant photoluminescence characteristics of the prepared phosphors indicate that they might serve as potential candidates for blue chip and near‐UV white light‐emitting diode applications. Copyright © 2015 John Wiley & Sons, Ltd.
Impact of thymine glycol damage on DNA duplex energetics: Correlations with lesion‐induced biochemical and structural consequences
Authors: Minetti Conceição A. S. A. , Remeta David P. , Iden Charles R. , Johnson Francis , Grollman Arthur P. , Breslauer Kenneth J. 
Published: May 2015

ABSTRACTThe magnitude and nature of lesion‐induced energetic perturbations empirically correlate with mutagenicity/cytotoxicity profiles and can be predictive of lesion outcomes during polymerase‐mediated replication in vitro. In this study, we assess the sequence and counterbase‐dependent energetic impact of the Thymine glycol (Tg) lesion on a family of deoxyoligonucleotide duplexes. Tg damage arises from thymine and methyl‐cytosine exposure to oxidizing agents or radiation‐generated free‐radicals. The Tg lesion blocks polymerase‐mediated DNA replication in vitro and the unrepaired site elicits cytotoxic lethal consequences in vivo. Our combined calorimetric and spectroscopic characterization correlates Tg‐induced energetic perturbations with biological and structural properties. Specifically, we incorporate a 5R‐Tg isomer centered within the tridecanucleotide sequence 5′‐GCGTACXCATGCG‐3′ (X = Tg or T) which is hybridized with the corresponding complementary sequence 5′‐CGCATGNGTACGC‐3′ (N = A, G, T, C) to generate families of Tg‐damaged (Tg·N) and lesion‐free (T·N) duplexes. We demonstrate that the magnitude and nature of the Tg destabilizing impact is dependent on counterbase identity (i.e., A ∼ G < T < C). The observation that a Tg lesion is less destabilizing when positioned opposite purines suggests that favorable counterbase stacking interactions may partially compensate lesion‐induced perturbations. Moreover, the destabilizing energies of Tg·N duplexes parallel their respective lesion‐free T·N mismatch counterparts (i.e., G < T < C). Elucidation of Tg‐induced destabilization relative to the corresponding undamaged mismatch energetics allows resolution of lesion‐specific and sequence‐dependent impacts. The Tg‐induced energetic perturbations are consistent with its replication blocking properties and may serve as differential recognition elements for discrimination by the cellular repair machinery. © 2015 Wiley Periodicals, Inc. Biopolymers 103: 491–508, 2015.
Multi‐omic profiling ­of EPO‐producing Chinese hamster ovary cell panel reveals metabolic adaptation to heterologous protein production
Authors: Ley Daniel , Seresht Ali Kazemi , Engmark Mikael , Magdenoska Olivera , Nielsen Kristian Fog , Kildegaard Helene Faustrup , Andersen Mikael Rørdam 
Published: May 2015

ABSTRACTChinese hamster ovary (CHO) cells are the preferred production host for many therapeutic proteins. The production of heterologous proteins in CHO cells imposes a burden on the host cell metabolism and impact cellular physiology on a global scale. In this work, a multi‐omics approach was applied to study the production of erythropoietin (EPO) in a panel of CHO‐K1 cells under growth‐limited and unlimited conditions in batch and chemostat cultures. Physiological characterization of the EPO‐producing cells included global transcriptome analysis, targeted metabolome analysis, including intracellular pools of glycolytic intermediates, NAD(P)H/NAD(P)+, adenine nucleotide phosphates (ANP), and extracellular concentrations of sugars, organic acids, and amino acids. Potential impact of EPO expression on the protein secretory pathway was assessed at multiple stages using quantitative PCR (qPCR), reverse transcription PCR (qRT‐PCR), Western blots (WB), and global gene expression analysis to assess EPO gene copy numbers, EPO gene expression, intracellular EPO retention, and differentially expressed genes functionally related to secretory protein processing, respectively. We found no evidence supporting the existence of production bottlenecks in energy metabolism (i.e., glycolytic metabolites, NAD(P)H/NAD(P)+ and ANPs) in batch culture or in the secretory protein production pathway (i.e., gene dosage, transcription and post‐translational processing of EPO) in chemostat culture at specific productivities up to 5 pg/cell/day. Time‐course analysis of high‐ and low‐producing clones in chemostat culture revealed rapid adaptation of transcription levels of amino acid catabolic genes in favor of EPO production within nine generations. Interestingly, the adaptation was followed by an increase in specific EPO productivity. Biotechnol. Bioeng. 2015;112: 2373–2387. © 2015 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.
Silks as scaffolds for skin reconstruction
Authors: Reimers Kerstin , Liebsch Christina , Radtke Christine , Kuhbier Jörn W. , Vogt Peter M. 
Published: May 2015

ABSTRACTIn this short review, we describe the use of high molecular weight proteins produced in the glands of several arthropods—commonly called silks—for the purpose to enhance human skin wound healing. To this end an extensive literature search has been performed, the publications have been categorized concerning silk preparation and application and summarized accordingly: Scaffolds to promote wound healing were prepared by processing the silks in different ways including solubilization of the protein fibers followed by casting or electrospinning. The silk scaffolds were additionally modified by coating or blending with the intention of further functionalization. In several approaches, the scaffolds were also vitalized with skin cells or stem cells. In vitro and in vivo models were implied to test for safety and efficiency. We conclude that silk scaffolds are characterized by an advantageous biocompatibility as well as an impressive versatility rendering them ideally suited for application in wounds. Nevertheless, further investigation is needed to exploit the full capacity of silk in different wound models and to achieve clinical transfer in time. Biotechnol. Bioeng. 2015;112: 2201–2205. © 2015 Wiley Periodicals, Inc.
Evaluating endoglucanase Cel7B‐lignin interaction mechanisms and kinetics using quartz crystal microgravimetry
Authors: Pfeiffer Katherine A. , Sorek Hagit , Roche Christine M. , Strobel Kathryn L. , Blanch Harvey W. , Clark Douglas S. 
Published: May 2015

ABSTRACTThe kinetics and mechanisms of protein interactions with solid surfaces are important to fields as diverse as industrial biocatalysis, biomedical engineering, food science, and cell biology. The nonproductive adsorption of cellulase enzymes to lignin, a plant cell wall polymer, reduces their effectiveness in saccharifying biomass. Cellulase has been shown to interact with lignin, but the heterogeneity of lignin surfaces, challenges in measuring irreversible components of these interactions, and fast adsorption rates make quantifying the reaction kinetics difficult. This work employs quartz crystal microgravimetry with dissipation monitoring (QCM‐D) for real‐time measurement of adsorbed mass on a flat lignin surface. We have developed a method for casting homogeneous lignin films that are chemically similar to lignin found in pretreated biomass, and used QCM‐D to compare three models of reversible‐irreversible binding behavior: a single‐site transition model, a transition model with changing adsorbate footprint, and a two‐site transition model. Of the three models tested, the two‐site transition model provides the only kinetic mechanism able to describe the behavior of Cel7B binding to lignin. While the direct implications of lignin‐cellulase interactions may be limited to biomass deconstruction for renewable energy and green chemistry, the analytical and experimental methods demonstrated in this work are relevant to any system in which the kinetics and reaction mechanism of reversible and irreversible protein adsorption at a solid‐liquid interface are important. Biotechnol. Bioeng. 2015;112: 2256–2266. © 2015 Wiley Periodicals, Inc.
Investigating the in vitro stereoselective metabolism of m‐nisoldipine enantiomers: characterization of metabolites and cytochrome P450 isoforms involved
Authors: Sun Yupeng , Jia Peipei , Yuan Lin , Liu Yanyan , Zhang Zhiyong , Du Yumin , Zhang Lantong 
Published: May 2015

Abstractm‐Nisoldipine, as a novel 1,4‐dihydropyridine calcium ion antagonist, was presented as a couple of enantiomers [(−), (+)‐m‐nisoldipine]. In this report, the in vitro metabolism of m‐nisoldipine enantiomers was investigated in rat liver microsomes (RLM) by the combination of two liquid chromatography mass spectrometric techniques for the first time. The metabolites were separated and assayed by ultra‐high performance liquid chromatography coupled to quadrupole time‐of‐flight mass spectrometry and further identified by comparison of their mass and chromatographic behaviors with reference substances. A total of 18 metabolites of (−)‐m‐nisoldipine and 16 metabolites of (+)‐m‐nisoldipine were detected, respectively, which demonstrated that (+)‐m‐nisoldipine is more metabolically stable than (−)‐m‐nisoldipine. In addition, the identified metabolic pathways of m‐nisoldipine enantiomers were involved in dehydrogenation, oxidation and ester hydrolysis. Afterwards, based on high‐performance liquid chromatography coupled to triple quadrupole linear ion trap mass spectrometry, various selective cytochrome P450 (CYP) enzyme inhibitors were employed to evaluate CYP isoforms. The results indicated that the inhibitors of CYP1A1/2, CYP2B1/2, 2D and 2C11 had no obvious inhibitory effects, yet the inhibitor of CYP 3A had a significant inhibitory effect on metabolism of m‐nisoldipine enantiomers. This showed that CYP 3A might primarily metabolize m‐nisoldipine in RLM. Copyright © 2015 John Wiley & Sons, Ltd.
Treatment patterns and outcomes in BRAF V600E‐mutant melanoma patients with brain metastases receiving vemurafenib in the real‐world setting
Authors: Gibney Geoffrey T. , Gauthier Geneviève , Ayas Charles , Galebach Philip , Wu Eric Q. , Abhyankar Sarang , Reyes Carolina , Guérin Annie , Yim Yeun Mi 
Published: May 2015

AbstractBrain metastases are a common and serious complication among patients with metastatic melanoma. The selective BRAF inhibitor vemurafenib has demonstrated clinical efficacy in patients with BRAF V600E‐mutant melanoma brain metastases (MBM). We examined the real‐world application and clinical outcomes of vemurafenib in this patient population. Demographic, treatment patterns, response, and survival data were collected from medical charts. Clinical data on 283 patients with active BRAF V600E‐mutant MBM treated with vemurafenib were provided by 70 US oncologists. Mean age was 57.2 years, 60.8% were male, 67.5% had ECOG performance status of 0–1, and 43.1% used corticosteroids at vemurafenib initiation. Median follow‐up was 5.7 months. Following vemurafenib initiation, 48.1% of patients experienced intracranial response and 45.6% experienced extracranial response. The Kaplan–Meier estimate for overall survival was 59% at 12 months. Multivariate analyses showed associations between intracranial response and both corticosteroid use and vemurafenib as initial therapy after MBM diagnosis. Larger size (5–10 mm vs. <5 mm) and number of brain metastases (≥5 vs. <2) and progressive extracranial disease at treatment initiation were associated with decreased intracranial response and increased risk of disease progression. Multiple extracranial sites (2 vs. <2) and the absence of local treatments were also associated with increased risk of progression. Increased risk of death was associated with ≥2 extracranial disease sites, progressive extracranial disease, and ≥5 brain metastases. Subgroups of MBM patients may derive more benefit with vemurafenib, warranting prospective investigation.
Chirality of Single‐Handed Twisted Titania Tubular Nanoribbons Prepared Through Sol‐gel Transcription
Authors: Wang Sibing , Zhang Chuanyong , Li Yi , Li Baozong , Yang Yonggang 
Published: May 2015

AbstractSingle‐handed twisted titania tubular nanoribbons were prepared through sol‐gel transcription using a pair of enantiomers. Handedness was controlled by that of the template. The obtained samples were characterized using field‐emission electron microscopy, transmission electron microscopy, diffuse reflectance circular dichroism (DRCD), and X‐ray diffraction. The DRCD spectra indicated that the titania nanotubes exhibit optical activity. Although the tubular structure was destroyed after being calcined at 700 °C for 2.0 h, DRCD signals were still identified. However, the DRCD signals disappeared after being calcined at 1000 °C for 2.0 h. The optical activity of titania was proposed to be due to chiral defects. Previous results showed that straight titania tubes could be used as asymmetric autocatalysts, indicating that titania exhibit chirality at the angstrom level. Herein, it was found that they also exhibit DRCD signals, indicating that there are no obvious relationships between morphology at the nano level and chirality at the angstrom level. The nanotube chirality should originate from the chiral defects on the nanotube inner surface. The Fourier transform infrared spectra indicated that the chirality of the titania was transferred from the gelators through the hydrogen bonding between N‐H and Ti‐OH. Chirality 27:543–550, 2015. © 2015 Wiley Periodicals, Inc.
Effectiveness of fecal immunochemical testing in reducing colorectal cancer mortality from the One Million Taiwanese Screening Program
Authors: Chiu Han‐Mo , Chen Sam Li‐Sheng , Yen Amy Ming‐Fang , Chiu Sherry Yueh‐Hsia , Fann Jean Ching‐Yuan , Lee Yi‐Chia , Pan Shin‐Liang , Wu Ming‐Shiang , Liao Chao‐Sheng , Chen Hsiu‐Hsi , Koong Shin‐Lan , Chiou Shu‐Ti 
Published: May 2015

BACKGROUNDThe effectiveness of fecal immunochemical testing (FIT) in reducing colorectal cancer (CRC) mortality has not yet been fully assessed in a large, population‐based service screening program.METHODSA prospective cohort study of the follow‐up of approximately 5 million Taiwanese from 2004 to 2009 was conducted to compare CRC mortality for an exposed (screened) group and an unexposed (unscreened) group in a population‐based CRC screening service targeting community residents of Taiwan who were 50 to 69 years old. Given clinical capacity, this nationwide screening program was first rolled out in 2004. In all, 1,160,895 eligible subjects who were 50 to 69 years old (ie, 21.4% of the 5,417,699 subjects of the underlying population) participated in the biennial nationwide screening program by 2009.RESULTSThe actual effectiveness in reducing CRC mortality attributed to the FIT screening was 62% (relative rate for the screened group vs the unscreened group, 0.38; 95% confidence interval, 0.35‐0.42) with a maximum follow‐up of 6 years. The 21.4% coverage of the population receiving FIT led to a significant 10% reduction in CRC mortality (relative rate, 0.90; 95% confidence interval, 0.84‐0.95) after adjustments for a self‐selection bias.CONCLUSIONSThis large, prospective Taiwanese cohort undergoing population‐based FIT screening for CRC had the statistical power to demonstrate a significant CRC mortality reduction, although the follow‐up time was short. Although such findings are informative for health decision makers, continued follow‐up of this large cohort will be required to estimate the long‐term impact of FIT screening if the covered population is expanded. Cancer 2015;121:3221–3229. © 2015 American Cancer Society.
Experiences in autotuning matrix multiplication for energy minimization on GPUs
Authors: Anzt Hartwig , Haugen Blake , Kurzak Jakub , Luszczek Piotr , Dongarra Jack 
Published: May 2015

SummaryIn this paper, we report extensive results and analysis of autotuning the computationally intensive graphics processing units kernel for dense matrix–matrix multiplication in double precision. In contrast to traditional autotuning and/or optimization for runtime performance only, we also take the energy efficiency into account. For kernels achieving equal performance, we show significant differences in their energy balance. We also identify the memory throughput as the most influential metric that trades off performance and energy efficiency. As a result, the performance optimal case ends up not being the most efficient kernel in overall resource use. Copyright © 2015 John Wiley & Sons, Ltd.
A platform to deploy customized scientific virtual infrastructures on the cloud
Authors: Caballer Miguel , Segrelles Damián , Moltó Germán , Blanquer Ignacio 
Published: May 2015

SummaryThis paper presents a software platform to dynamically deploy complex scientific virtual computing infrastructures, on top of Infrastructure as a Service Clouds. The platform orchestrates different services to provision the virtual computing resources. It dynamically installs the appropriate software to satisfy the requirements of a researcher, both on public and on‐premise Clouds. The platform provides a web interface to enable the users to easily manage the life cycle of virtual infrastructures. It enables users to define infrastructures, share them with other users, deploy and relinquish them, add or remove resources dynamically, create and share application recipes, and so on. The paper also describes three case studies to deploy complex infrastructures, namely, a Hadoop cluster, a single‐node to perform Next Generation Sequencing and a gateway for users to access the European Grid Infrastructure. This platform promotes a better use of on‐premise hardware resources of a research center by allocating the computing resources just‐in‐time to the specific life time of the virtual infrastructures as well as the deployment of the very same infrastructures on a public Cloud. Copyright © 2015 John Wiley & Sons, Ltd.