bluuebunny/crossref_metadata_2025 huggingface dataset:
Hierarchically Mesostructured Polyisobutylene‐Based Ionic Liquids
Authors: Appiah Clement , Akbarzadeh Johanna , Stojanovic‐Marinow Anja , Peterlik Herwig , Binder Wolfgang H.
Published: March 2016

The formation and design of a hierarchically nanostructured poly(isobutylene)‐based ionic liquid (PIB‐ILs) is reported, displaying assembly into classical multiplets and an additional ordering of the aromatic counteranions. Three PIB‐ILs (Mn = 3600 and 8600 g mol−1), bearing imidazolium (1a), N‐methylpyrrolidinium (1b), and triethylammonium cations (1c) together with the aromatic 2‐(methylthio)benzoate anion are prepared via a combination of living carbocationic polymerization, “click” reactions and subsequent anion metathesis. The morphology of the novel PIB‐ILs as well as its temperature‐dependent behavior has been studied via small angle X‐ray scattering, displaying two different transition temperatures: one originating from ordering of micelles within a cylinder, and the second from cylinder–cylinder arrangement. Furthermore, the incorporation of an aromatic, rigid, and bulky 2‐(methylthio)benzoate anion into the PIB‐ILs effects the formation of an internal assembly consisting of stacked cylindrical structures, composed from the mesoscale ordering of ionic “multiplets” characteristic for classical ionomers and from the typical distance of the cylinders themselves.

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Effect of Overconfidence on Cournot Competition in the Presence of Yield Uncertainty
Authors: Pu Xujin , Jin Delong , Han Guanghua
Published: March 2016

This study investigates the effects of overconfidence on a Cournot competition subject to yield uncertainty. We consider one of two firms to be overconfident, whereas the other is completely rational and derive the Nash equilibrium to compare with that when both firms are completely rational. Through this comparison and analysis, we establish that (i) the relationship between a firm's overconfidence and the likelihood of that firm developing a monopoly in the market is positive; (ii) a rational firm always suffers a loss because of its competitor's overconfidence in a Cournot competition; and (iii) an overconfident firm does not benefit constantly from its overconfidence, although overconfidence results in permanent, increased, and more aggressive market sharing in competitions. Copyright © 2016 John Wiley & Sons, Ltd.
Relearning of Writing Skills in Parkinson's Disease After Intensive Amplitude Training
Authors: Nackaerts Evelien , Heremans Elke , Vervoort Griet , Smits‐Engelsman Bouwien C.M. , Swinnen Stephan P. , Vandenberghe Wim , Bergmans Bruno , Nieuwboer Alice
Published: March 2016

Background

Micrographia occurs in approximately 60% of people with Parkinson's disease (PD). Although handwriting is an important task in daily life, it is not clear whether relearning and consolidation (ie the solid storage in motor memory) of this skill is possible in PD. The objective was to conduct for the first time a controlled study into the effects of intensive motor learning to improve micrographia in PD.

Methods

In this placebo‐controlled study, 38 right‐handed people with PD were randomized into 2 groups, receiving 1 of 2 equally time‐intensive training programs (30 min/day, 5 days/week for 6 weeks). The experimental group (n = 18) performed amplitude training focused at improving writing size. The placebo group (n = 20) received stretch and relaxation exercises. Participants' writing skills were assessed using a touch‐sensitive writing tablet and a pen‐and‐paper test, pre‐ and posttraining, and after a 6‐week retention period. The primary outcome was change in amplitude during several tests of consolidation: (1) transfer, using trained and untrained sequences performed with and without target zones; and (2) automatization, using single‐ and dual‐task sequences.

Results

The group receiving amplitude training significantly improved in amplitude and variability of amplitude on the transfer and automatization task. Effect sizes varied between 7% and 17%, and these benefits were maintained after the 6‐week retention period. Moreover, there was transfer to daily life writing.

Conclusions

These results show automatization, transfer, and retention of increased writing size (diminished micrographia) after intensive amplitude training, indicating that consolidation of motor learning is possible in PD. © 2016 International Parkinson and Movement Disorder Society
Linkage and related analyses of Barrett's esophagus and its associated adenocarcinomas
Authors: Sun Xiangqing , Elston Robert , Falk Gary W. , Grady William M. , Faulx Ashley , Mittal Sumeet K. , Canto Marcia I. , Shaheen Nicholas J. , Wang Jean S. , Iyer Prasad G. , Abrams Julian A. , Willis Joseph E. , Guda Kishore , Markowitz Sanford , Barnholtz‐Sloan Jill S. , Chandar Apoorva , Brock Wendy , Chak Amitabh
Published: March 2016

Background

Familial aggregation and segregation analysis studies have provided evidence of a genetic basis for esophageal adenocarcinoma (EAC) and its premalignant precursor, Barrett's esophagus (BE). We aim to demonstrate the utility of linkage analysis to identify the genomic regions that might contain the genetic variants that predispose individuals to this complex trait (BE and EAC).

Methods

We genotyped 144 individuals in 42 multiplex pedigrees chosen from 1000 singly ascertained BE/EAC pedigrees, and performed both model‐based and model‐free linkage analyses, using S.A.G.E. and other software. Segregation models were fitted, from the data on both the 42 pedigrees and the 1000 pedigrees, to determine parameters for performing model‐based linkage analysis. Model‐based and model‐free linkage analyses were conducted in two sets of pedigrees: the 42 pedigrees and a subset of 18 pedigrees with female affected members that are expected to be more genetically homogeneous. Genome‐wide associations were also tested in these families.

Results

Linkage analyses on the 42 pedigrees identified several regions consistently suggestive of linkage by different linkage analysis methods on chromosomes 2q31, 12q23, and 4p14. A linkage on 15q26 is the only consistent linkage region identified in the 18 female‐affected pedigrees, in which the linkage signal is higher than in the 42 pedigrees. Other tentative linkage signals are also reported.

Conclusion

Our linkage study of BE/EAC pedigrees identified linkage regions on chromosomes 2, 4, 12, and 15, with some reported associations located within our linkage peaks. Our linkage results can help prioritize association tests to delineate the genetic determinants underlying susceptibility to BE and EAC.
Existence and global exponential stability of almost periodic solution for delayed competitive neural networks with discontinuous activations
Authors: Tan Yanxiang , Jing Ke
Published: March 2016

In this paper, we study a class of delayed competitive neural networks with discontinuous activations. Without assuming the boundedness and local Lipschizian on the activation functions, some new criteria ensuring the existence and global exponential stability of almost periodic solutions for the neural network model considered in this work are established by constructing some suitable Lyapunov functionals and employing the theory of nonsmooth analysis. Finally, we present some applications and numerical examples with simulations to show the effectiveness of our main results. Copyright © 2016 John Wiley & Sons, Ltd.
Infinitely many peak solutions for a biharmonic equation involving critical exponent
Authors: Liu Zhongyuan
Published: March 2016

In this paper, we study the following biharmonic equation

urn:x-wiley:mma:media:mma3792:mma3792-math-0001
where
, K(1) > 0,K′(1) > 0, B1(0) is the unit ball in
(N≥6). We show that the aforementioned problem has infinitely many peak solutions, whose energy can be made arbitrarily large. Copyright © 2016 John Wiley & Sons, Ltd.
Some remarks on quasilinear wave equations with null condition in 3‐D
Authors: Zha Dongbing
Published: March 2016

In this paper, we give an alternative proof to the global existence result, which is originally owing to the pioneering work of Klainerman and Christodoulou, for the Cauchy problem of quasilinear wave equations with null condition in three space dimensions. The proof can display the following three features simultaneously: the Lorentz boost operator is not employed in the generalized energy estimates; the generalized energy of the solution will be always small, which was first observed by Alinhac; and the initial data are not assumed to have a compact support. Copyright © 2016 John Wiley & Sons, Ltd.
Punicalagin attenuates palmitate‐induced lipotoxicity in HepG2 cells by activating the Keap1‐Nrf2 antioxidant defense system
Authors: Yan Chunhong , Sun Wenyan , Wang Xun , Long Jiangang , Liu Xuebo , Feng Zhihui , Liu Jiankang
Published: March 2016

Scope

Free fatty acids (FFA) could induce hepatocyte lipotoxicity, which plays an important role in the initiation of nonalcoholic fatty liver disease (NAFLD). Inhibition of FFA‐induced lipotoxicity is suggested as a potential treatment for nonalcoholic fatty liver disease. The aim of the current study is to explore the effect of punicalagin, a polyphenol abundant in pomegranate, on FFA‐induced hepatic lipotoxicity and its potential mechanisms.

Methods and results

HepG2 cells were exposed to 250 μM palmitate for 24 h with or without punicalagin pretreatment. Punicalagin pretreatment attenuated palmitate‐induced mitochondrial membrane potential lost, ATP depletion, and reactive oxygen species production. Punicalagin also increased hepatocyte viability by blocking mitochondria‐mediated caspase‐dependent apoptosis. The hepatoprotective effect was associated with an exaggerated phosphorylation of extracellular signal regulated kinase as well as significant nuclear factor erythroid 2‐related factor 2 (Nrf2) nuclear translocation and target genes induction. Blockage of extracellular signal regulated kinase by a pharmacological inhibitor abrogated the cytoprotective effect of punicalagin and its induction of Nrf2 pathway. Knockdown of Nrf2 by specific small interfering RNA also diminished the protective effects of punicalagin, while knockdown of Kelch‐like ECH‐associated protein 1 (Keap1) with small interfering RNA could promote Nrf2 nuclear translocation and exert similar protection as punicalagin treatment.

Conclusions

These findings suggest that punicalagin could effectively attenuate FFA‐induced lipotoxicity by activating Keap1‐Nrf2 cytoprotective signaling pathway.
Rhubarb extract prevents hepatic inflammation induced by acute alcohol intake, an effect related to the modulation of the gut microbiota
Authors: Neyrinck Audrey M. , Etxeberria Usune , Taminiau Bernard , Daube Georges , Van Hul Matthias , Everard Amandine , Cani Patrice D. , Bindels Laure B. , Delzenne Nathalie M.
Published: March 2016

Scope

Binge consumption of alcohol is an alarming global health problem. Acute ethanol intoxication is characterized by hepatic inflammation and oxidative stress, which could be promoted by gut barrier function alterations. In this study, we have tested the hypothesis of the hepatoprotective effect of rhubarb extract in a mouse model of binge drinking and we explored the contribution of the gut microbiota in the related metabolic effects.

Methods and results

Mice were fed a control diet supplemented with or without 0.3% rhubarb extract for 17 days and were necropsied 6 h after an alcohol challenge. Supplementation with rhubarb extract changed the microbial ecosystem (assessed by 16S rDNA pyrosequencing) in favor of Akkermansia muciniphila and Parabacteroides goldsteinii. Furthermore, it improved alcohol‐induced hepatic injury, downregulated key markers of both inflammatory and oxidative stresses in the liver tissue, without affecting significantly steatosis. In the gut, rhubarb supplementation increased crypt depth, tissue weight, and the expression of antimicrobial peptides.

Conclusions

These findings suggest that some bacterial genders involved in gut barrier function, are promoted by phytochemicals present in rhubarb extract, and could therefore be involved in the modulation of the susceptibility to hepatic diseases linked to acute alcohol consumption.
Cyanidin‐3‐glucoside and its phenolic acid metabolites attenuate visible light‐induced retinal degeneration in vivo via activation of Nrf2/HO‐1 pathway and NF‐κB suppression
Authors: Wang Yong , Huo Yazhen , Zhao Liang , Lu Feng , Wang Ou , Yang Xue , Ji Baoping , Zhou Feng
Published: March 2016

Scope

Cyanidin‐3‐glucoside (C3G) is a major anthocyanin in berries and a potential nutritional supplement for preventing retinal degeneration. However, the protective mechanism of C3G and its metabolites, protocatechuic acid (PCA) and ferulic acid (FA), remain unclear. The molecular mechanisms of C3G and its metabolites against retinal photooxidative damage in vivo are investigated.

Methods and results

Pigmented rabbits were orally administered C3G, PCA, and FA (0.11 mmol/kg/day) for 3 weeks. Electroretinography, histological analysis, and TUNEL assay showed that C3G and its metabolites attenuated retinal cell apoptosis. The expression of oxidative stress markers were upregulated after light exposure but attenuated by C3G and FA, which may be attributed to the elevated secretion and expression of heme oxygenase (HO‐1) and nuclear factor erythroid‐2 related factor 2 (Nrf2). C3G, PCA, and FA attenuated the secretion or expression of inflammation‐related genes; FA suppressed nuclear factor kappa B (NF‐κB) activation. The treatments attenuated the light‐induced changes on certain apoptotic proteins and angiogenesis‐related cytokines.

Conclusion

C3G and FA reduced light‐induced retinal oxidative stress by activating the Nrf2/HO‐1 antioxidant pathway. FA attenuated the light‐induced retinal inflammation by suppressing NF‐κB activation. C3G and its metabolites attenuated the photooxidation‐induced apoptosis and angiogenesis in the retina.
Modeling the Radical Batch Homopolymerization of Acrylamide in Aqueous Solution
Authors: Preusser Calista , Chovancová Anna , Lacík Igor , Hutchinson Robin A.
Published: March 2016

A kinetic model for the radical homopolymerization of acrylamide in aqueous solution is developed, incorporating propagation and termination rate coefficients as functions of monomer concentration and including the formation and reaction of midchain radicals based on the insights and measured rate coefficients from recent pulsed‐laser studies. The model successfully represents the batch conversion profiles measured using an in situ NMR technique between 40 and 70 °C with initial monomer concentrations of 5 to 40 wt%, as well as the associated polymer molar mass distributions. In particular, the model captures the decreased rate that occurs at lowered monomer concentrations as a result of the formation of less‐active midchain radicals by backbiting. Previous literature data are also well represented by the model.

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Least‐squares method for the Oseen equation
Authors: Cai Zhiqiang , Chen Binghe
Published: March 2016

This article studies the least‐squares finite element method for the linearized, stationary Navier–Stokes equation based on the stress‐velocity‐pressure formulation in d dimensions (d = 2 or 3). The least‐squares functional is simply defined as the sum of the squares of the L2 norm of the residuals. It is shown that the homogeneous least‐squares functional is elliptic and continuous in the
norm. This immediately implies that the a priori error estimate of the conforming least‐squares finite element approximation is optimal in the energy norm. The L2 norm error estimate for the velocity is also established through a refined duality argument. Moreover, when the right‐hand side f belongs only to
, we derive an a priori error bound in a weaker norm, that is, the
norm. © 2016 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 32: 1289–1303, 2016
Optimal control for a singularly perturbed linear stochastic system with multiplicative white noise perturbations and Markovian jumping
Authors: Dragan Vasile , Mukaidani Hiroaki
Published: March 2016

In this study, we investigate the optimal control of a class of singularly perturbed linear stochastic systems with Markovian jumping parameters. After establishing an asymptotic structure for the stabilizing solution of the coupled stochastic algebraic Riccati equations, a parameter‐independent composite controller is derived. Furthermore, the cost degradation in a reduced‐order controller is discussed. Thus, the exactness of the proposed approximate control is discussed for the first time. As an additional important contribution, a numerical algorithm for solving the coupled stochastic algebraic Riccati equations is proposed, and the feature of the resulting higher‐order controller is shown. Finally, a simple example is presented to demonstrate the validity of the proposed method. Copyright © 2016 John Wiley & Sons, Ltd.
Polymeric microtubes for water filtration by co‐axial electrospinning technique
Authors: Halaui Rafi , Zussman Eyal , Khalfin Rafail , Semiat Raphael , Cohen Yachin
Published: March 2016

Co‐axial electrospinning technique has proved to be a reliable way of producing thin and small hollow fibers with a symmetric or asymmetric structure that may be useful for water treatment. All the hollow fibers produced had an inner diameter of up to 4 µm and average wall thickness of 600 nm. Poly(vinylidene fluoride‐co‐hexa fluoro propylene) hollow fibers exhibited a dense structure while the addition of poly(ethylene glycol) changed its structure to an asymmetric one, with a dense layer on both inner and outer sides. The semicrystalline copolylmer fibers exhibited a fibrillar structure. Hollow fibers made of the homopolymer poly(vinylidene fluoride) exhibited an asymmetric structure, while polysulfone or poly(ether imide) hollow fibers exhibited a symmetric porous structure. Copyright © 2016 John Wiley & Sons, Ltd.
Cooperative effects of nucleation agent and plasticizer on crystallization properties of stereocomplex‐type poly(lactide acid)
Authors: Cui Li , Wang Yahui , Guo Yi , Liu Yun , Zhao Jinchao , Zhang Chuanjie , Zhu Ping
Published: March 2016

An investigation of the cooperative effects of plasticizer (PEG) and nucleation agent (TMC‐306) on stereocomplex‐type poly(lactide acid) formation and crystallization behaviors between poly(L‐lactide acid) (PLLA) and poly(D‐lactide acid) (PDLA) was conducted. Wide‐angle X‐ray diffraction (WAXD) and differential scanning calorimetry (DSC) analysis indicated that exclusive stereocomplex‐type poly(lactide acid) (sc‐PLA) crystallites without any homocrystallites poly(lactide acid) (hc‐PLA) did form by incorporation of PEG, TMC‐306, or both at a processing temperature higher than the melting temperature of sc‐PLA (around 230°C). The non‐isothermal and isothermal crystallization kinetics showed that PEG and TMC‐306 could independently accelerate the crystallization rate of sc‐PLA. The crystallization peak temperature and crystallization rate of sc‐PLA were significantly improved by the presence of PEG and TMC‐306. The influence of PEG and TMC‐306 on the morphologies of sc‐PLA was also investigated using polarized optical microscopy (POM). Copyright © 2016 John Wiley & Sons, Ltd.
Mechanical property evaluation of glass–jute fiber reinforced polymer composites
Authors: Rafiquzzaman Md. , Islam Maksudul , Rahman Habibur , Talukdar Saniat , Hasan Nahid
Published: March 2016

The natural fibers such as jute, coir, hemp, sisal etc. are randomly used as reinforcements for composite materials because of its various advantages such as low cost, low densities, low energy consumption over conventional fibers. In addition, they are renewable as well as biodegradable, and indeed wide varieties of fibers are locally available. In this study, glass–jute fiber reinforced polymer composite is fabricated, and the mechanical properties such as tensile, flexural and impact behavior are investigated. The materials selected for the studies were jute fiber and glass fiber as the reinforcement and epoxy resin as the matrix. The hand lay‐out technique was used to fabricate these composites. Fractured surface were comprehensively examined in scanning electron microscope (SEM) to determine the microscopic fracture mode. A numerical procedure based on the finite element method was then applied to evaluate the overall behavior of this composite using the experimentally applied load. Results showed that by incorporating the optimum amount of jute fibers, the overall strength of glass fiber reinforced composite can be increased and cost saving of more than 30% can be achieved. It can thus be inferred that jute fiber can be a very potential candidate in making of composites, especially for partial replacement of high‐cost glass fibers for low load bearing applications. Copyright © 2016 John Wiley & Sons, Ltd.
Nonlinear vibration and instability of rotating piezoelectric nanocomposite sandwich cylindrical shells containing axially flowing and rotating fluid–particle mixture
Authors: Arani Ali Ghorbanpour , Karimi Mohammad Saeed , Bidgoli Mahmood Rabani
Published: March 2016

Axially flowing and rotating fluid‐particle mixture‐induced vibration and instability of a sandwich cylindrical shell are the main contribution of this work. The sandwich structure is made from a functionally graded carbon nanotube‐reinforced composite (CNTRC) cylindrical shell integrated with piezoelectric sensor and actuator layers. In this regard, the perturbation velocity potential is introduced and the pressure exerted by a fluid is obtained by the linearized Bernoulli formula. The actuator layer is subjected to an applied voltage in thickness direction which operates in control of vibration and stability. Based on Mindlin shell theory, the motion equations are derived and solved by the differential quadrature method (DQM). A detailed parametric study is conducted to elucidate the influences of the vibrational modes, distribution type and volume fractions of single‐walled carbon nanotubes (SWCNTs), boundary conditions, volume percent of particles and applied voltage on the vibration and instability of the structure. Results indicate that the system becomes unstable in the form of flutter in the cases of angular rotation of the shell or fluid as well as axial flow and angular rotation of the fluid while in the case of the rotating shell containing a corotating fluid, the loss of stability does not occur. POLYM. COMPOS., 38:E577–E596, 2017. © 2016 Society of Plastics Engineers
Outcomes of stage I TTTS or liquor discordant twins: a single‐centre review
Authors: Hinch Ellen , Henry Amanda , Wilson Isabella , Welsh Alec W.
Published: March 2016

Objectives

To investigate rates of progression, regression and stabilisation and outcomes for stage I twin–twin transfusion syndrome (TTTS) and significant liquor discordant (LD) monochorionic diamniotic (MCDA) twins referred to the New South Wales Fetal Therapy Centre between June 2007 and May 2013.

Methods

Retrospective cohort study of 329 monochorionic referrals, of whom 47 had LD and 28 had stage I TTTS at presentation; 43 were stage I or higher at any time during surveillance. Clinical progression, rates of therapy, survival and associated complications were evaluated.

Results

Of stage I cases, 64% (18/28) remained stable or regressed, with 60% (6/10) of those progressing becoming at least stage II within 2 weeks. Of LD cases, 7/47 (15%) progressed to stage I TTTS, 8/47 (17%) to stage II or higher and 3/47 (6%) to selective intrauterine growth restriction (38% total).

Conclusion

While a stable clinical picture was the most common outcome in stage I/LD presentations, progression to stage ≥ II TTTS occurred in 36 and 17% respectively, indicating that LD is not a benign finding. Rapid progression in the majority of progressive cases and modest overall survival rates support close surveillance of these pregnancies and investigation of laser therapy as a first‐line treatment of stage I TTTS. © 2016 John Wiley & Sons, Ltd.
Predictors of prevalent statin use among older adults identified as statin initiators based on Medicare claims data
Authors: Young Jessica C. , Stürmer Til , Lund Jennifer L. , Funk Michele Jonsson
Published: March 2016

Purpose

Few studies have evaluated the degree to which prescription drug initiators are correctly identified using claims data. We examine the prevalence and predictors of recent statin possession in statin initiators identified using claims data.

Methods

Among Medicare Current Beneficiary Survey (MCBS) respondents, we used Medicare Part D claims from 2006 to 2011 to identify statin initiators using a 12‐month baseline period of no prior statin claims. Using MCBS interview data, we identified those with self‐reported statins obtained during the baseline period. We used log‐binomial regression to estimate adjusted prevalence ratios (adjPR) and 95% confidence intervals (CI) for predictors of recent statin possession.

Results

Among 766 statin initiators identified in prescription claims, 155 (20%) reported recent statin possession during baseline. Beneficiaries with no Part D claims in the past 30 days (adjPR = 1.49, 95%CI: 1.13, 1.96), those with no inpatient, outpatient or physician visits in the past 30 days (adjPR = 1.50, 95%CI: 1.11, 2.03), those with a brand name statin index claim (adjPR = 1.55, 95%CI: 1.19, 2.02), and those with an index claim in January or February (adjPR = 1.50, 95%CI: 1.00, 2.26) had an increased probability of recent statin possession.

Conclusions

In a cohort of statin initiators identified using prescription claims, 20% had evidence of statin possession during the baseline period. Pharmacoepidemiologic new user studies may benefit from including sensitivity analyses within subgroups less likely to include prevalent users to assess the robustness of key findings to misidentification of the time of treatment initiation. Copyright © 2016 John Wiley & Sons, Ltd.
Microwave‐crosslinked bio‐based starch/clay aerogels
Authors: Wang Liang , Sánchez‐Soto Miguel , Abt Tobias , Maspoch Maria Lluisa , Santana Orlando O
Published: March 2016

Foam‐like robust starch/sodium montmorillonite (Na+‐MMT) aerogels were fabricated through a freeze‐drying process. Glutaraldehyde (GL) was used to crosslink the starch aerogels with the assistance of radiation supplied by a domestic microwave oven. The chemical reaction between GL and starch was analysed using Fourier transform infrared spectroscopy and water swelling tests. The microstructures and mechanical properties of the resultant crosslinked starch aerogels changed with GL concentration. By incorporating 5% (w/w) GL, the specific compressive modulus and absorbed energy increased by 2.4 and 3.3 times, respectively. In regard to starch/clay aerogel composites, Na+‐MMT clay played the role of reinforcement. Moreover, clay addition created more porous structures and hence decreased the thermal conductivity of the aerogels. The biodegradability of the aerogels was studied using a homemade micro‐respirometer. The starch aerogels exhibited higher biodegradability than poly(vinyl alcohol)‐based ones and their corresponding films. © 2016 Society of Chemical Industry
Fluorescent vapochromism in synthetic polymers
Authors: Minei Pierpaolo , Pucci Andrea
Published: March 2016

The detection of volatile organic compounds (VOCs) by means polymeric materials through fluorescence variations has attracted considerable interest over the past 10 years. The detection of VOCs is of great concern because of their undesirable impact on both the environment and human health. Moreover, the sensing of vapours of organic compounds such as explosives is one pressing issue in anti‐terrorism and homeland security. In this mini‐review, the current state of knowledge concerning the preparation of fluorescent polymers with vapochromic features is summarized. Two types of procedures are illustrated and thoroughly discussed along with their respective structure–property relationships: the first resides on the covalent insertion of chromophoric units into the macromolecule backbone or side chains; the second involves the physical dispersion of the fluorophore in a preformed polymer matrix. Herein we review the simplicity of the preparative routes available, and their influence over the properties of the resulting fluorophore–polymer systems, by focusing on the most illustrative examples described in the literature. Finally, conclusive remarks and future perspectives are presented and discussed. © 2016 Society of Chemical Industry
Novel poly(3‐hydroxybutyrate) composite films containing bioactive glass nanoparticles for wound healing applications
Authors: Francis Lydia , Meng Decheng , Locke Ian C , Knowles Jonathan C , Mordan Nicola , Salih Vehid , Boccaccini Aldo R , Roy Ipsita
Published: March 2016

Bioactive glass is considered an ideal material for haemostasis as it releases Ca2+ ions upon hydration, which is required to support thrombosis. In this study the effects of the presence of nanoscaled bioactive glass (n‐BG) in poly(3‐hydroxybutyrate) (P(3HB)) microsphere films on the structural properties, thermal properties and biocompatibility of the films were studied. The n‐BG with a high surface area was also tested for its in vitro haemostatic efficacy and was found to be able to successfully reduce clot detection time. In an effort to study the effect of the roughness induced by the formation of hydroxyapatite on cellular functions such as cell adhesion, cell mobility and cell differentiation, the composite films were immersed in simulated body fluid for periods of 1, 3 and 7 days. From scanning electron microscopy images, the surface of the P(3HB)/n‐BG composite microsphere films appeared fairly uniform and smooth on day 1; however on day 3 and day 7 a rough and uneven surface was observed. The presence of hydroxyapatite on the composite microsphere films on day 3 and day 7 influenced the surface roughness of the films. However, when the P(3HB)/n‐BG composite microsphere films with enhanced surface roughness were tested for biocompatibility, reduced amounts of protein adsorption and cell adhesion were observed. This study thus revealed that there is an optimal surface roughness for the P(3HB) microsphere films for increased cell adhesion, beyond which it could be deleterious for cell adhesion and differentiation. © 2016 Society of Chemical Industry
MALDI‐TOF and nESI Orbitrap MS/MS identify orthogonal parts of the phosphoproteome
Authors: Ruprecht Benjamin , Roesli Christoph , Lemeer Simone , Kuster Bernhard
Published: March 2016

Phosphorylation is a reversible posttranslational protein modification which plays a pivotal role in intracellular signaling. Despite extensive efforts, phosphorylation site mapping of proteomes is still incomplete motivating the exploration of alternative methods that complement existing workflows. In this study, we compared tandem mass spectrometry (MS/MS) on matrix assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) and nano‐electrospray ionization (nESI) Orbitrap instruments with respect to their ability to identify phosphopeptides from complex proteome digests. Phosphopeptides were enriched from tryptic digests of cell lines using Fe‐IMAC column chromatography and subjected to LC‐MS/MS analysis. We found that the two analytical workflows exhibited considerable orthogonality. For instance, MALDI‐TOF MS/MS favored the identification of phosphopeptides encompassing clear motif signatures for acidic residue directed kinases. The extent of orthogonality of the two LC‐MS/MS systems was comparable to that of using alternative proteases such as Asp‐N, Arg‐C, chymotrypsin, Glu‐C and Lys‐C on just one LC‐MS/MS instrument. Notably, MALDI‐TOF MS/MS identified an unexpectedly high number and percentage of phosphotyrosine sites (∼20% of all sites), possibly as a direct consequence of more efficient ionization. The data clearly show that LC‐MALDI MS/MS can be a useful complement to LC‐nESI MS/MS for phosphoproteome mapping and particularly so for acidic and phosphotyrosine containing peptides.
Visible‐light‐sensitive photoredox catalysis by iron complexes: Applications in cationic and radical polymerization reactions
Authors: Zhang Jing , Campolo Damien , Dumur Frederic , Xiao Pu , Fouassier Jean Pierre , Gigmes Didier , Lalevée Jacques
Published: March 2016

The development of iron complexes for the photoredox catalysis is a huge challenge. Indeed, Iron complexes can be ideal candidates due to their potential visible light absorption and redox properties but also because they are less toxic, inexpensive and environmentally friendly compared to other catalysts. In the present paper, a series of novel iron complexes have been synthesized and utilized to initiate the free radical promoted cationic polymerization of epoxides or the free radical polymerization of acrylates through photoredox catalysis processes upon exposure to near UV (385 nm) or visible violet (405 nm) light emitting diodes (LEDs). When combined with an iodonium salt and N‐vinylcarbazole, the iron complex‐based photoinitiating systems are able to generate radicals, cations, and radical cations. The initiation efficiency is investigated through real‐time Fourier transform infrared spectroscopy and a satisfactory initiating ability is found. The mechanisms for the generation of the reactive initiating species through photoredox catalysis are studied by different methods (steady state photolysis, cyclic voltammetry and electron spin resonance spin trapping techniques) and discussed in detail. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2247–2253
Plasticization and cocrystallization in LLDPE/wax blends
Authors: Gumede Thandi P. , Luyt Adriaan S. , Pérez‐Camargo Ricardo A. , Iturrospe Amaia , Arbe Arantxa , Zubitur Manuela , Mugica Agurtzane , Müller Alejandro J.
Published: March 2016

The structure and thermal properties of linear low‐density polyethylene (LLDPE)/medium soft paraffin wax blends, prepared by melt mixing, were investigated by differential scanning calorimetry (DSC) and small‐ and wide‐angle X‐ray scattering (SAXS and WAXS). The blends form a single phase in the melt as determined by SAXS. Upon cooling from the melt, two crystalline phases develop for blends with more than 10 wt % wax characterized by widely different melting points. The wax acts as an effective plasticizer for LLDPE, decreasing both its crystallization and melting temperature. The higher melting point crystalline phase is formed by less branched LLDPE fractions. On the other hand, the lower melting point crystalline phase is a wax‐rich phase constituted by cocrystals of extended chain wax and short linear sequences of highly branched LLDPE chains. The presence of cocrystals was evidenced by standard DSC results, successive self‐nucleation and annealing (SSA) thermal fractionation and by the detection of a new SAXS signal attributed to the lamellar long period of the cocrystals. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 1469–1482
Tidal volume measurements in infants: Opto‐electronic plethysmography versus pneumotachograph
Authors: Reinaux Cyda Maria Albuquerque , Aliverti Andrea , da Silva Lívia Gabriely Melo , da Silva Rafael Justino , Gonçalves Juliane Neves , Noronha Jessica Brito , Filho José Eulálio Cabral , de Andrade Armèle Dornelas , de Amorim Britto Murilo Carlos
Published: March 2016

Tidal breathing measurements by Opto‐Electronic Plethysmography (OEP) has been reported for infants limited to protocols with two chest wall compartments. Standard protocol for the analysis of adults, with three compartments of chest wall, has been unavailable for analysis of infants. We aimed to study the agreement of simultaneous measurements of tidal volume by OEP (VT,OEP) and a heated pneumotachograph (PNT) (VT,PNT) performed during sleeping in 20 infants (gestational age 35.1 ± 4.6 weeks) at 3–4 months postconceptual age with a three compartment protocol. From PNT and OEP measurements, tidal volume corrected (VT,PNT) for ambient conditions were calculated with a total number of 200 breaths. The two methods were in good agreement with tidal volume mean difference of 0.02 ml and limit of agreement −4.11 to 4.08 ml (95%CI), no relationship was found between differences and means of OEP and PNT measurements. Pulmonary rib cage, abdominal rib cage and abdomen contributed by 12.4 ± 9.7%, 5.2 ± 5.1%, and 82.4 ± 11.4% to VT,OEP, respectively. The OEP experimental protocol based on 52 markers and a three‐compartment model of the chest wall could be used in spontaneously sleeping infants. Pediatr Pulmonol. 2016;51:850–857. © 2016 Wiley Periodicals, Inc.
The massless spectrum of heterotic compactifications
Authors: de la Ossa Xenia , Hardy Edward , Svanes Eirik Eik
Published: March 2016

We discuss the four‐dimensional massless spectrum of supersymmetric Minkowski compactifications of ten‐dimensional heterotic supergravity, including the anomaly cancelation condition. This can be calculated from restrictions arising from F‐term conditions in a four dimensional effective theory. The results agree with computations of the infinitesimal moduli space recently performed from a ten‐dimensional perspective. The paper is based on a talk given by Eirik Eik Svanes in Leuven for the workshop on 'The String Theory Universe'.
AdS (in)stability: an analytic approach
Authors: Craps Ben , Evnin Oleg
Published: March 2016

We briefly review the topic of AdS (in)stability, mainly focusing on a recently introduced analytic approach and its interplay with numerical results.
Lessons in process safety management learned in the Kaohsiung gas explosion accident in Taiwan
Authors: Liaw Horng‐Jang
Published: March 2016

A series of explosions attributed to leakage of propylene from an underground pipeline resulted in 32 fatalities and 321 injuries in Kaohsiung, Taiwan, in 2014. An analysis of this gas explosion indicated that such an accident could have been prevented, or the consequences might not have been as severe if certain elements of process safety management (PSM) had been applied. Proper execution of PSM, including management of change, mechanical integrity, process hazard analysis (PHA), process safety information (PSI), and training, can prevent the occurrence of such explosion accidents. The impact of this explosion could have been reduced had these PSM elements, particularly PHA, operating procedures, training, PSI, and emergency planning and response, been executed. © 2016 American Institute of Chemical Engineers Process Saf Prog 35: 228–232, 2016
Create a firm process safety foundation for your new facilities
Authors: Edwards Victor H.
Published: March 2016

Documented here is the acceptance speech of the 2015 Norton H. Walton‐Russell L. Miller Award of the Safety and Health Division of AIChE. The award was presented to Dr. Victor H. Edwards at the annual division banquet at the Global Congress on Process Safety in Austin, TX on April 28, 2015. The speech emphasizes the crucial role that process safety should play in the concept, siting, and design of process plants. © 2016 American Institute of Chemical Engineers Process Saf Prog 35: 258–259, 2016
Reliability aspects of hydrogen‐doped indium oxide
Authors: Jost Gabrielle C. E. , Hamri Alexander N. , Köhler Florian , Hüpkes Jürgen
Published: March 2016

We demonstrate an alternative route to reliably prepare hydrogen‐doped indium oxide (In2O3:H). The common hydrogen source, water vapor, was substituted in our process by hydrogen and oxygen gas. The resulting films showed similar optical and electrical properties. Nevertheless, the process using gaseous hydrogen led to a simplification of the deposition process. By replacing the hydrogen source we increased the reproducibility of the electrical film properties significantly, thus, paving the way for a reliable device implementation of the material. Furthermore, we investigated the degradation behavior of In2O3:H under damp heat conditions as preliminary test for long‐term durability in photovoltaic devices. The results revealed a degradation of the electrical properties that differs in detail regarding the amorphous and polycrystalline material. In the amorphous material, the main degradation is caused by loss of charge carriers, whereas in the polycrystalline material a drop of the charge carrier mobility causes a significant rise of the resistivity. However, we show that the relative degradation of the In2O3:H films is similar to other transparent contacts that are implemented in solar cells. Finally, we demonstrate that the degradation of the charge carrier mobility in the polycrystalline In2O3:H films is completely reversible by vacuum annealing at 200 °C.
Photoluminescence of microcrystalline silicon at low temperatures
Authors: Burdorf Sven , Brüggemann Rudolf
Published: March 2016

Abstractauthoren Photoluminescence (PL) from semiconductors can be related with the quasi‐Fermi level splitting of the electron‐hole‐ensemble from which the radiation originates. For the interpretation of the temperature‐dependent c‐Si:H PL Planck's generalized law is extended and applied to describe the radiative recombination via band‐tail states. This substantial refinement of existing approaches allows for the modeling of temperature‐dependent spectra over the entire measured temperature range and furthermore provides access to the quasi‐Fermi level splitting (qFL) of electron‐hole ensembles in the thin film and furthermore yields quantitative information on band‐tail energies. In crystalline silicon, an increase in the quasi‐Fermi level splitting causes only an increase in the overall PL‐intensity, while the spectral shape of the spectrum is unaffected. In contrast, the PL‐spectra of c‐Si:H differ with varying qFL‐splitting both in intensity and shape. Only by introducing variations of qFL‐splitting and constructing an overall PL‐spectrum that is a superposition from excitation states with different qFL‐splittings, the experimental temperature‐dependent PL spectra from c‐Si:H can be reconstructed for the entire temperature range.

Temperature‐dependent PL spectra of c‐Si:H silicon (symbols) and fits according to our proposed model (lines).
Theoretical investigation of the stability of defect complexes in silicon
Authors: Abgaryan Karine , Mutigullin Ilya
Published: March 2016

In this work theoretical investigation of the stability of various defect complexes including vacancies, self‐interstitials and their clusters was performed by means of ab initio as well as molecular dynamic calculations. Meta‐stable defect configurations similar to those observed earlier experimentally were found. Also the software for the molecular dynamic calculations and for the visualization of calculation results was developed. The results of the first‐principles calculations were used for the parametrical fitting of Tersoff potential of silicon. Obtained potential was used to perform molecular dynamic calculations of the various configurations of defects in silicon. This approach allowed us to study the dynamics of the atomic system over time and temperature range. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic spectrum of Bi‐related defects in crystalline CdTe
Authors: Krivobok Vladimir , Nikolaev Sergey , Onischenko Evgeny , Pruchkina Anna , Kolosov Sergey , Klevkov Yuri , Bagaev Victor
Published: March 2016

Using measurements of conductivity and low‐temperature photoluminescence, we have studied electronic levels in the band gap of CdTe:Bi and CdTe:Bi,Cl single crystals grown by the modified Bridgman technique. Three type of deep levels (EV+0.29 eV, EV+0.4 eV, EV+0.72 eV) and Bi‐related shallow acceptor have been observed depending on the doping conditions. Energy spectrum of a shallow Bi‐related acceptor has been measured and its low symmetry has been established. The tentative interpretation for all the levels observed has been proposed. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural, optical and magnetic characteristics of II‐VI semiconductor nanocrystal‐graphene hybrid nanostructures
Authors: Savchuk Andriy I. , Stolyarchuk Ihor D. , Savchuk Serhii A. , Sheregij Eugeniusz M. , Polit Jacek
Published: March 2016

CdS, CdTe, ZnO, and ZnO:Co nanocrystals and related hybrid nanostructures, in which the nanoparticles combined with graphene, have been studied. Different chemical approaches for synthesis of II‐VI semiconductor nanocrystal‐graphene hybrids have been applied depending on chemical composition. Transmission electron microscopy characterizations proved the formation of graphene based hybrid nanostructures. Absorption spectra near band‐gap edge have shown changes due to the interaction of the nanocrystals with graphene. The revealed photoluminescence quenching effect in II‐VI semiconductor nanocrystal‐graphene hybrids can be served as evidence for electron transfer from the nanoparticles to graphene. Results of Faraday rotation measurements in doped ZnO:Co nanocrystals and their hybrids at room temperature demonstrated paramagnetic behaviour for both kinds of samples. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The efficiency droop impact of GaN‐based LEDs on the performance of OFDM visible light communication system
Authors: Lu Huimin , Yu Tongjun , Jia Chuanyu , Zhang Yini , Wang Jianping , Zhang Guoyi
Published: March 2016

The physical mechanism in efficiency droop of GaN‐based LEDs fabricated by metal organic chemical vapor deposition (MOCVD) was investigated by experiment and calculation. On this basis, the efficiency droop impact on the performance of orthogonal frequency division multiplexing (OFDM) visible‐light communication (VLC) system was analyzed. The numerical results show that the VLC system performance decreases obviously under the impact of the LED efficiency droop. And, the performance deterioration of OFDM VLC system aggravates as FFT sampling rate increase due to signal dynamic range enlargement. Furthermore, the efficiency droop impact on the VLC performance can be alleviated by adjusting the LED operating condition. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Corrosion and tribocorrosion behaviour of super‐thick diamond‐like carbon films deposited on stainless steel in NaCl solution
Authors: Pu Jibin , Wang Junjun , He Dongqing , Wan Shanhong
Published: March 2016

Super‐thick diamond‐like carbon (DLC) film is a potential protective coating in corrosive environments. In the present work, three kinds of DLC films whose thickness and modulation periods are 4 µm and 3, 21 µm and 17 and 21 µm and 7, respectively, were fabricated on stainless steel. The effect of different thickness and modulation periods on corrosion and tribocorrosion behaviour of the DLC‐coating stainless steel was investigated in 3.5 wt% NaCl aqueous solution by a ball‐on‐flat tribometer equipped with a three‐electrode electrochemical cell. The DLC‐coating stainless steel served as a working electrode, and its OCP and potentiodynamic polarization were monitored before and during rubbing. The wear–corrosion mechanism of the DLC films was investigated by SEM. The results showed that the increasing thickness can prolong significantly lifetime of DLC films in NaCl aqueous solution. In particular, the modulation period has a significant impact on the tribocorrosion resistance of the DLC super‐thick films. The study suggested that the increasing thickness of compressive stress layer could suppress film damage by reducing crack propagation rate. Thus, the super‐thick DLC film with thickness of 21 µm and 7 periods presented the best tribocorrosion resistance among all studied films. Copyright © 2016 John Wiley & Sons, Ltd.