bluuebunny/crossref_metadata_2025 huggingface dataset:
δ‐Catenin interacts with LEF‐1 and negatively regulates its transcriptional activity
Authors: He Yongfeng , Ki Hyunkyoung , Kim Hangun , Kim Kwonseop
Published: March 2015

δ‐Catenin and β‐catenin belong to different subfamilies of armadillo proteins but share some common binding partners, such as E‐cadherin. This is the first study that demonstrated a novel common binding partner for δ‐catenin and β‐catenin, lymphoid enhancer factor‐1 (LEF‐1). We found that the N‐terminus of δ‐catenin (amino acids 85–325) bound to the middle region of LEF‐1 unlike β‐catenin. Overexpressed δ‐catenin entered the nucleus and inhibited LEF‐1‐mediated transcriptional activity in Bosc23 and DLD‐1 cell lines. The current study provided novel insights that will provide a better understanding of the effects of δ‐catenin on Wnt/LEF‐1‐mediated transcriptional activity.
Importance of Myc‐related microRNAs in induced pluripotency
Authors: Çağlayan E. Sacide , Güran Şefik
Published: March 2015

Pluripotent stem cells (PSCs) have the capacity to differentiate into any cell type of the body. Therefore, induced pluripotent stem cells (iPSCs) are seen as a promising solution for patient‐specific cell therapies. However, the safety is major issue for in vitro methods that are used in induction of pluripotency and also in differentiation of PSCs toward specific cell types. In pioneer studies of iPSC generation, the role of c‐Myc has been highlighted as a possible master regulator of pluripotency, but direct c‐Myc overexpression is known to prompt drawbacks, especially in human cells. In recent studies, the role of non‐protein coding RNA molecules such as microRNAs (miRNAs) has been shown in enhanced reprogramming efficiency. In addition, new reprogramming methods have been ultimately improved by adding miRNAs, in the absence of previous factors. Cross interaction between miRNAs and c‐Myc has been also found in differentiation of iPSCs, as well as in reprogramming and self‐renewing the pluripotent state. Thence, miRNAs are promising solution for efficiency and safety of iPSC derivation and differentiation methods. The purpose of the present review is to evaluate interaction mechanisms of miRNAs with c‐Myc and in iPSC technology.
Advanced Oxygen Sensing for Accurate Gas Diffusivity Measurements in Fuel Cells
Authors: Lv Weiqiang , Feng Na , Huo Weirong , Niu Yinghua , Wang Siyuan , Wang Xiaoning , Liang Yachun , Zhu Gaolong , He Weidong
Published: March 2015

Impeded gas diffusion causes serious concentration polarization (CP) in fuel cells. The facile and accurate measurement of gas diffusivities in various electrodes facilitates the pre‐evaluation of two key parameters in fuel cells, that is, the limiting current density (LCD) and CP. However, previously reported electrochemical devices for this purpose only employ a single oxygen voltage sensor, which induces inevitable voltage errors, owing to the existing oxygen gradient across the measurement tube. In this report, the correlation of such voltage errors with the errors of diffusivity measurement as well as the errors in pre‐evaluating LCD and CP is analyzed quantitatively. A dual oxygen‐sensing device is then proposed for the first time to eliminate the voltage errors, allowing for accurate diffusivity measurements and reliable pre‐evaluation of LCD and CP in fuel cells with both bulk and thin nanostructured electrodes operated at different temperatures.
Covariances Simultaneous Component Analysis: a new method within a framework for modeling covariances
Authors: Smilde Age K. , Timmerman Marieke E. , Saccenti Edoardo , Jansen Jeroen J. , Hoefsloot Huub C. J.
Published: March 2015

In modern omics research, it is more rule than exception that multiple data sets are collected in a study pertaining to the same biological organism. In such cases, it is worthwhile to analyze all data tables simultaneously to arrive at global information of the biological system. This is the area of data fusion or multi‐set analysis, which is a lively research topic in chemometrics, bioinformatics, and biostatistics. Most methods of analyzing such complex data focus on group means, treatment effects, or time courses. There is also information present in the covariances among variables within a group, because this relates directly to individual differences, heterogeneity of responses, and changes of regulation in the biological system.

We present a framework for analyzing covariance matrices and a new method that fits nicely in this framework. This new method is based on combining covariance prototypes using simultaneous components and is, therefore, coined Covariances Simultaneous Component Analysis (COVSCA). We present the framework and our new method in mathematical terms, thereby explaining the (dis)similarities of the methods.

Systems biology models based on differential equations illustrate the type of variation generated in real‐life biological systems and how this type of variation can be modeled within the framework and with COVSCA. The method is subsequently applied to two real‐life data sets from human and plant metabolomics studies showing biologically meaningful results. Copyright © 2015 John Wiley & Sons, Ltd.
The Structural Influence of Graphene Oxide on Its Fragmentation during Laser Desorption/Ionization Mass Spectrometry for Efficient Small‐Molecule Analysis
Authors: Kim Young‐Kwan , Min Dal‐Hee
Published: March 2015

The structural influence of graphene oxide (GO) on laser desorption/ionization mass spectrometry (LDI‐MS) analysis of small molecules was systematically investigated by using size‐fractionated GO. For fractionation of GO, pH‐assisted centrifugation, sequential vacuum filtration, and sonochemical cutting processes were employed and the size‐fractionated GO was thoroughly characterized to understand their size‐dependent optochemical properties. Then, the fractionated GO was applied to the analysis of various small molecules by LDI‐MS to investigate the relationship between their optochemical properties and LDI‐MS performance. We found that large GO sheets (>0.5 μm) were more prone to fragmentation under laser irradiation during LDI‐MS analysis than small GO sheets (<0.5 μm). In this regard, the LDI‐MS analysis efficiency of various small molecules was significantly improved by using nanosized GO (NGO) as a matrix without background interference. In particular, NGO was successfully applied to the sensitive detection of hydrophobic pollutant molecules without requiring any surface‐functionalization, enrichment, and separation process. Therefore, the present study could provide important basic information and be a practical tool for the development of simple and efficient LDI‐MS platforms by using GO derivatives.
The Acidity of the HBr/AlBr3 System: Stabilization of Crystalline Protonated Arenes and Their Acidity in Bromoaluminate Ionic Liquids
Authors: Scholz Franziska , Himmel Daniel , Eisele Lea , Unkrig Wiebke , Martens Arthur , Schlüter Peter , Krossing Ingo
Published: March 2015

Bulk protonated mesitylene, toluene, and benzene bromoaluminate salts were stabilized and characterized in the superacidic system HBr/n AlBr3 with NMR spectroscopy and X‐ray analysis of [HC6H3(CH3)3]+[AlBr4]− (1), [HC6H5(CH3)]+[AlBr4]− (2), and [C6H7]+[Al2Br7]−⋅C6H6 (3). Protonation attempts in bromoaluminate ILs led to a complete protonation of mesitylene, and a protonation degree of up to 15 % for toluene in the IL BMP+[Al2Br7]−. Benzene could only be protonated in the more acidic IL BMP+[Al3Br10]−, with a degree of 25 %. Protonation attempts on aromatics provide evidence that the bromoaluminate ILs tolerate superacidic environments. On the basis of the absolute Brønsted acidity scale, quantum chemical calculations confirmed the superacidic properties, and rank the acidities in ILs down to a pHabs value of 164 with an error of less than one pH unit compared with experimental findings. The neat AlBr3/HBr system even may reach acidities down to pHabs 163.
Valence Bond and Enzyme Catalysis: A Time To Break Down and a Time To Build Up
Authors: Sharir‐Ivry Avital , Varatharaj Rajapandian , Shurki Avital
Published: March 2015

Understanding enzyme catalysis and developing ability to control of it are two great challenges in biochemistry. A few successful examples of computational‐based enzyme design have proved the fantastic potential of computational approaches in this field, however, relatively modest rate enhancements have been reported and the further development of complementary methods is still required. Herein we propose a conceptually simple scheme to identify the specific role that each residue plays in catalysis. The scheme is based on a breakdown of the total catalytic effect into contributions of individual protein residues, which are further decomposed into chemically interpretable components by using valence bond theory. The scheme is shown to shed light on the origin of catalysis in wild‐type haloalkane dehalogenase (wt‐DhlA) and its mutants. Furthermore, the understanding gained through our scheme is shown to have great potential in facilitating the selection of non‐optimal sites for catalysis and suggesting effective mutations to enhance the enzymatic rate.
Development of Modifiable Bidentate Amino Oxazoline Directing Group for Pd‐Catalyzed Arylation of Secondary CH Bonds
Authors: Chen Kang , Li Zhao‐Wei , Shen Peng‐Xiang , Zhao Hong‐Wei , Shi Zhang‐Jie
Published: March 2015

A novel bidentate α‐amino oxazolinyl directing group has been developed. Different from previous directing groups, this newly designed directing group was easily prepared from amino acids and modified in structure. This auxiliary preferentially effects functionalization at secondary C(sp3)H bonds, rather than at aryl C(sp2)H bonds. The diastereoselectivity of direct arylation between geminal secondary C(sp3)H bonds in linear molecules has also been realized for the first time with a chiral directing group by remote chirality relay. Two diastereoisomers are produced with the same chiral source by changing the substituents of substrates and aryl halides.
Simulation of One‐Stage Dimethyl Ether Synthesis over a Core‐Shell Catalyst
Authors: Ding Wenjin , Klumpp Michael , Lee Seungcheol , Reuß Stephanie , Al‐Thabaiti Shaeel A. , Pfeifer Peter , Schwieger Wilhelm , Dittmeyer Roland
Published: March 2015

A spherical microsized core‐shell catalyst (CuO/ZnO/Al2O3@H‐ZSM‐5) was synthesized for direct dimethyl ether synthesis from syngas in a micro packed bed reactor. To assist in the preparation and optimization of the core‐shell catalyst, a 1D heterogeneous model was developed to simulate diffusion and reactions within the catalyst particles. Using the data obtained from the tubular reactor, kinetic parameters for the catalyst were determined first. Furthermore, simulation showed that thickness and activity of shell have significant effect on the catalytic performance of the core‐shell catalyst.
Effects of the dynein inhibitor ciliobrevin on the flagellar motility of sea urchin spermatozoa
Authors: Wada Yuuko , Baba Shoji A. , Kamimura Shinji
Published: March 2015

Ciliobrevin has recently been found to be a membrane‐permeable inhibitor that is specific to AAA+ molecular motors such as cytoplasmic dyneins. In this study, we investigated how ciliobrevin inhibited the motility of sperm from sea urchins: Hemicentrotus pulcherrimus, Pseudocentrotus depressus, and Anthocidaris crassispina. After application of 100 μM of ciliobrevin A to live spermatozoa, swimming speed decreased gradually and flagellar motion stopped almost completely within 5 to 10 min. This inhibition was reversible and the frequency of flagellar beating was reduced in a concentration‐dependent manner. Ciliobrevin had similar inhibitory effects on the flagellar beating of demembranated and reactivated sperm and the sliding disintegration of trypsin‐treated axonemes. We also analyzed the curvature and shear angle of the beating flagella and found that the proximal region of the sperm flagellum was less sensitive to ciliobrevin compared with more distal regions, where bending motions were blocked completely. Interestingly, the shear angle analysis of flagellar motility showed that ciliobrevin induced highly asymmetric bends in the proximal region of the flagellum. These results suggest that there is heterogeneity in the inhibitory thresholds of dynein motors, which depend on the regions along the flagellar shaft (proximal or distal) and on the sites of doublets in the flagellar cross‐section (doublet numbers). We expect that it will be possible to map the functional differences in dynein subtypes along and/or around the cross‐sections of flagellar axonemes by analyzing the inhibitory effects of ciliobrevin. © 2015 Wiley Periodicals, Inc.
Actin–myosin network influences morphological response of neuronal cells to altered osmolarity
Authors: Bober Brian G. , Love James M. , Horton Steven M. , Sitnova Mariya , Shahamatdar Sina , Kannan Ajay , Shah Sameer B.
Published: March 2015

Acute osmotic fluctuations in the brain occur during a number of clinical conditions and can result in a variety of adverse neurological symptoms. Osmotic perturbation can cause changes in the volumes of intra‐ and extracellular fluid and, due to the rigidity of the skull, can alter intracranial pressure thus making it difficult to analyze purely osmotic effects in vivo. The present study aims to determine the effects of changes in osmolarity on SH‐SY5Y human neuroblastoma cells in vitro, and the role of the actin–myosin network in regulating this response. Cells were exposed to hyper‐ or hypoosmotic media and morphological and cytoskeletal responses were recorded. Hyperosmotic shock resulted in a drop in cell body volume and planar area, a persisting shape deformation, and increases in cellular translocation. Hypoosmotic shock did not significantly alter planar area, but caused a transient increase in cell body volume and an increase in cellular translocation via the development of small protrusions rich in actin. Disruption of the actin–myosin network with latrunculin and blebbistatin resulted in changes to volume and shape regulation, and a decrease in cellular translocation. In both osmotic perturbations, no apparent disruptions to cytoskeletal integrity were observed by light microscopy. Overall, because osmotically induced changes persisted even after volume regulation occurred, it is possible that osmotic stress may play a larger role in neurological dysfunction than currently believed. © 2015 Wiley Periodicals, Inc.
Polymorphism in New Thienothiophene–Thiazolothiazole Organic Semiconductors
Authors: Schneider Julia A. , Black Hayden , Lin Hua‐Ping , Perepichka Dmitrii F.
Published: March 2015

Charge transport in organic semiconductors is heavily influenced by their solid‐state packing. To separate intermolecular packing effects from molecular electronic effects, we have synthesized two polymorphs of crystalline thienothiophene–thiazolothiazole trimers and studied them by DFT calculations, optical spectroscopy, single‐crystal X‐ray diffraction and charge‐transport measurements in field‐effect transistors. One polymorph was found to be a p‐type semiconductor with a hole mobility of 3.3×10−3 cm2 V−1 s−1, while the other was insulating. The different charge‐transport behavior and optical properties of the two polymorphs are strongly related to the topology of their π‐stacks. Subtle differences between the polymorphs, including S⋅⋅⋅S close contacts and bond‐length alternation are also discussed for their possible effects on charge transport.
Oxidation of Organosilanes with Nanoporous Copper as a Sustainable Non‐Noble‐Metal Catalyst
Authors: Li Zhiwen , Xu Xiaohong , Zhang Xiaomei
Published: March 2015

Although many noble‐metal catalysts have been used for the oxidation of organosilanes, there has been less success with non‐noble‐metal catalysts. Here, unsupported nanoporous copper (np‐Cu) is used to catalyze the oxidation of organosilanes under mild conditions. It is the first time that this reaction has been achieved with a heterogeneous copper catalyst with high activity and selectivity. Both water and alcohols are used as oxidants and the corresponding organosilanols and organosilyl ethers are obtained in high yield. The possible mechanism was obtained by kinetic studies. The catalyst could be reused at least five times without evident loss of activity. As a novel green catalyst np‐Cu should play a unique role in organic synthesis.
Safety of antidiabetes medications: An update
Authors: Bailey CJ
Published: March 2015

Adverse iatrogenic effects of especial relevance for antidiabetes medications include hypoglycemic episodes, major adverse cardiovascular (CV) events, cancer, bone fractures, pancreatic effects, genital/urinary tract infections, and weight gain. Here, recent clinical studies addressing safety profiles of antidiabetes medications are reviewed. On balance, new prospective and population‐based studies continue to indicate that the benefits of improved glucose control outweigh the risks associated with antidiabetes medications in most patients with type 2 diabetes.
Cross‐Metathesis of Biosourced Fatty Acid Derivatives: A Step Further Toward Improved Reactivity
Authors: Vignon Paul , Vancompernolle Tom , Couturier Jean‐Luc , Dubois Jean‐Luc , Mortreux André , Gauvin Régis M.
Published: March 2015

Invited for the cover of this issue is the group of Régis Gauvin at the Unit for Catalysis and Solid State Chemistry, Université Lille Nord de France. The image shows how cross‐metathesis of bio‐sourced fatty esters can be efficiently performed using internal functionalized olefins. The Communication itself is available at 10.1002/cssc.201403170.
Push applications and dynamic content generation over content‐centric networking
Authors: Virgilio Matteo , Marchetto Guido , Sisto Riccardo
Published: March 2015

Content‐Centric Networking (CCN) represents an established candidate for the future Internet, proposing a routing architecture designed to elevate content to first class entity. Starting from the fact that the network usage has dramatically evolved towards content retrieval, CCN relies on an on‐demand pull based mechanism to transfer data from the different sources to the heterogeneous consumers. This paradigm enhances the network in a number of ways, ranging from the newly introduced in‐network caching capabilities to the benefits provided by the symmetric data routing adopted by CCN. In this renewed network scenario, we place our attention to those applications that do not perfectly fit the pull paradigm, stating that they need to be supported as well and proposing an effective way to achieve scalability on large scale push applications. We provide the following contributions: (i) we identify the functions that a data‐centric architecture should support; (ii) propose and compare our solution with the state of the art framework designed for the specific problem of pushing data to content requesters; and (iii) evaluate their performance in terms of traffic generated and scalability achieved by simulating a real Internet Service Provider (ISP) topology and the realistic workload of a generic social network application. Copyright © 2015 John Wiley & Sons, Ltd.
The influence of adolescent eating disorders or disordered eating behaviors on socioeconomic achievement in early adulthood
Authors: Tabler Jennifer , Utz Rebecca L.
Published: March 2015

Objective

Much research documents the etiology and health consequences of adolescent eating disorders (ED), but very little is known about the long‐term effects of EDs on the transition to adulthood. This study explores gender differences in the influence of EDs or disordered eating behaviors (DEB) on measures of socioeconomic independence in early adulthood.

Method

Using the National Longitudinal Study of Adolescent Health (Add Health), this study compares individuals who self‐identified as have been diagnosed with an ED or engaged in DEBs in late adolescence to those without ED or DEB on three measures of socioeconomic independence during early adulthood, including educational attainment, income, and likelihood of owning a home. This study uses multiple regression techniques and attempts to account for early‐life conditions and health outcomes associated with EDs and DEBs.

Results

For females, ED or DEB in late adolescence had a statistically significant, negative association with educational attainment (coefficient = −0.20, p = .05), personal income (coefficient = −0.12, p < .05) and odds of owning a home (odds ratio = 0.73, p < .02) in early adulthood. For males, ED or DEB was not associated with socioeconomic attainment.

Discussion

Our findings suggest that EDs and DEBs are negatively associated with socioeconomic achievement during early adulthood for females, but not for males. EDs or DEBs during adolescence may set individuals on a different trajectory whereby they do not have the same life chances or opportunities for success in adulthood. These results confirm the public health message that EDs or DEBs have lasting negative consequences for women. © 2015 Wiley Periodicals, Inc. (Int J Eat Disord 2015; 48:622–632)
Household Energy Use and Carbon Emissions in China: A decomposition analysis
Authors: Zhu Qin , Wei Taoyuan
Published: March 2015

Although its per‐capita carbon emissions are still relatively low, China's aggregated carbon emissions have grown nearly four‐fold in the last three decades, and now it is the biggest CO2 emitter in the world. There are many reasons for this emissions growth, and much emphasis has been placed on industrial development, but previous research has estimated that 40% of the growth in Chinese CO2 emissions over the 15 years to 2007 can be attributed to household energy consumption. Here we conduct a decomposition analysis to show that in the period from 1978 to 2008 nearly 60% of the growth in Chinese household emissions can be attributed to the increasing number of households and 40% to increasing emissions per household. We also show that over this period emissions growth in urban households has been six times that of rural households. These results have important implications for policy‐makers seeking to promote reductions in China's CO2 emissions, relating for example to family planning and urbanization. Copyright © 2015 John Wiley & Sons, Ltd and ERP Environment
Electrochemical Sensors Using Two‐Dimensional Layered Nanomaterials
Authors: Su Shao , Chao Jie , Pan Dun , Wang Lianhui , Fan Chunhai
Published: March 2015

Two‐dimensional (2D) layered nanomaterials, e.g. graphene and molybdenum disulfide (MoS2), have rapidly emerged in material sciences due to their unique physical, chemical and mechanical properties. In the meanwhile, there is a growing interest in constructing electrochemical sensors for a wide range of chemical and biological molecules by using these 2D nanomaterials. In this review, we summarize recent advances on using graphene and MoS2 for the development of electrochemical sensors for small molecules, proteins, nucleic acids and cells detection. We also provide our perspectives in this rapidly developing field.
Preparation, Characterization and Electrochemical Application of ZnO‐CuO Nanoplates for Voltammetric Determination of Captopril and Tryptophan Using Modified Carbon Paste Electrode
Authors: Beitollahi Hadi , Ghofrani Ivari Susan , Alizadeh Reza , Hosseinzadeh Rahman
Published: March 2015

2‐chlorobenzoyl ferrocene, was synthesized and used to construct a modified ZnO‐CuO nanoplates modified carbon paste electrode. The electrooxidation of captopril at the surface of the modified electrode was studied. Under the optimized conditions, the square wave voltammetric (SWV) peak current of captopril increased linearly with captopril concentration in the range of 5.0×10−7 to 9.0×10−4 M and detection limit of 90.0 nM was obtained for captopril. The diffusion coefficient and kinetic parameters (such as electron transfer coefficient and the heterogeneous rate constant) for captopril oxidation were also determined. The prepared modified electrode exhibits a very good resolution between the voltammetric peaks of captopril and tryptophan which makes it suitable for the detection of captopril in the presence of tryptophan in real samples.
A portable and integrated instrument for cell manipulation by dielectrophoresis
Authors: Burgarella Sarah , Bari Marco Di
Published: March 2015

The physical manipulation of biological cells is a key point in the development of miniaturized systems for point‐of‐care analyses. Dielectrophoresis (DEP) has been reported by several laboratories as a promising method in biomedical research for label‐free cell manipulation without physical contact, by exploiting the dielectric properties of cells suspended in a microfluidic sample, under the action of high‐gradient electric fields. In view of a more extended use of DEP phenomena in lab‐on‐chip devices for point‐of‐care settings, we have developed a portable instrument, integrating on the same device the microfluidic biochip for cell manipulation and all the laboratory functions (i.e., DEP electric signal generation, microscopic observation of the biological sample under test and image acquisition) that are normally obtained by combining different nonportable standard laboratory instruments. The nonuniform electric field for cell manipulation on the biochip is generated by microelectrodes, patterned on the silicon substrate of microfluidic channels, using standard microfabrication techniques. Numerical modeling was performed to simulate the electric field distribution, quantify the DEP force, and optimize the geometry of the microelectrodes. The developed instrument includes an electronic board, which allows the control of the electric signal applied to electrodes necessary for DEP, and a miniaturized optical microscope system that allows visual inspection and eventually cell counting, as well as image and video recording. The system also includes the control software. The portable and integrated platform described in this work therefore represents a complete and innovative solution of applied research, suitable for many biological applications.
Exploratory ensemble designs for environmental models using k‐extended Latin Hypercubes
Authors: Williamson D.
Published: March 2015

In this paper we present a novel, flexible, and multi‐purpose class of designs for initial exploration of the parameter spaces of computer models, such as those used to study many features of the environment. The idea applies existing technology aimed at expanding a Latin Hypercube (LHC) in order to generate initial LHC designs that are composed of many smaller LHCs. The resulting design and its component parts are designed so that each is approximately orthogonal and maximises a measure of coverage of the parameter space. Designs of the type advocated for in this paper are particularly useful when we want to simultaneously quantify parametric uncertainty and any uncertainty due to the initial conditions, boundary conditions, or forcing functions required to run the model. This makes the class of designs particularly suited to environmental models, such as climate models that contain all of these features. The proposed designs are particularly suited to initial exploratory ensembles whose goal is to guide the design of further ensembles aimed at, for example, calibrating the model. We introduce a new emulator diagnostic that exploits the structure of the advocated ensemble designs and allows for the assessment of structural weaknesses in the statistical modelling. We provide illustrations of the method through a simple example and describe a 400 member ensemble of the Nucleus for European Modelling of the Ocean (NEMO) ocean model designed using the method. We build an emulator for NEMO using the created design to illustrate the use of our emulator diagnostic test. © 2015 The Authors.Environmetricspublished by John Wiley & Sons Ltd.
Photochemical and microbial transformation of emerging flame retardants: Cause for concern?
Authors: Chen Da , Hale Robert C. , Letcher Robert J.
Published: March 2015

Among anthropogenic chemicals, flame retardants have attracted mounting environmental concerns. In recent years, an increasing number of studies have been conducted worldwide to investigate flame-retardant sources, environmental distribution, wildlife and human exposure, and toxicity. Data generated have demonstrated that some flame-retardant substances such as polybrominated diphenyl ethers (PBDE) are persistent, bioaccumulative, and toxic to exposed organisms. However, comparatively much less attention has been paid to the mechanisms and products of environmental transformation of flame retardants. This lack of information undermines our understanding of the environmental behavior and fate of flame retardants, as well as the associated risks to environmental and human health. Photochemical and microbial transformation of flame retardants in various matrices and environmental compartments can elevate the toxicological significance of flame retardant exposure, via the formation of, for example, lesser halogenated but more bioaccumulative degradation products and toxic radicals. Such pathways raise concerns related to the environmental safety of some alternative flame retardants that are presumably safe and used to replace PBDEs. To fully assess the environmental risks, more research is needed to investigate the environmental transformation potential of emerging flame retardants including polymeric flame retardants. Enhanced analytical efforts are needed to better characterize transformation products and transient radicals. Additional mesocosm and field studies are needed to elucidate transformation kinetics and consequences under environmentally relevant conditions. Environ Toxicol Chem 2015;34:687–699. © 2015 SETAC
On the approximate zeroth and first‐order consistency in the presence of 2‐D irregular boundaries in SPH obtained by the virtual boundary particle methods
Authors: Fourtakas Georgios , Vacondio Renato , Rogers Benedict D.
Published: March 2015

In this paper, a new method to impose 2‐D solid wall boundary conditions in smoothed particle hydrodynamics is presented. The wall is discretised by means of a set of virtual particles and is simulated by a local point symmetry approach. The extension of a previously published modified virtual boundary particle (MVBP) method guarantees that arbitrarily complex domains can be readily discretised guaranteeing approximate zeroth and first‐order consistency. To achieve this, three important new modifications are introduced: (i) the complete support is ensured not only for particles within one smoothing length distance, h, from the boundary but also for particles located at a distance greater than h but still within the support of the kernel; (ii) for a non‐uniform fluid particle distribution, the fictitious particles are generated with a uniform stencil (unlike the previous algorithms) that can maintain a uniform shear stress on a particle‐moving parallel to the wall in a steady flow; and (iii) the particle properties (density, mass and velocity) are defined using a local point of symmetry to satisfy the hydrostatic conditions and the Cauchy boundary condition for pressure. The extended MVBP model is demonstrated for cases including hydrostatic conditions for still water in a tank with a wedge and for curved boundaries, where significant improved behaviour is obtained in comparison with the conventional boundary techniques. Finally, the capability of the numerical scheme to simulate a dam break simulation is also shown. Copyright © 2015 John Wiley & Sons, Ltd.
A boundary element method for the solution of finite mobility ratio immiscible displacement in a Hele‐Shaw cell
Authors: Jackson S. J. , Stevens D. , Power H. , Giddings D.
Published: March 2015

In this paper, the interaction between two immiscible fluids with a finite mobility ratio is investigated numerically within a Hele‐Shaw cell. Fingering instabilities initiated at the interface between a low‐viscosity fluid and a high‐viscosity fluid are analysed at varying capillary numbers and mobility ratios using a finite mobility ratio model.

The present work is motivated by the possible development of interfacial instabilities that can occur in porous media during the process of CO2 sequestration but does not pretend to analyse this complex problem. Instead, we present a detailed study of the analogous problem occurring in a Hele‐Shaw cell, giving indications of possible plume patterns that can develop during the CO2 injection.

The numerical scheme utilises a boundary element method in which the normal velocity at the interface of the two fluids is directly computed through the evaluation of a hypersingular integral. The boundary integral equation is solved using a Neumann convergent series with cubic B‐Spline boundary discretisation, exhibiting sixth‐order spatial convergence. The convergent series allows the long‐term nonlinear dynamics of growing viscous fingers to be explored accurately and efficiently.

Simulations in low‐mobility ratio regimes reveal large differences in fingering patterns compared with those predicted by previous high‐mobility ratio models. Most significantly, classical finger shielding between competing fingers is inhibited. Secondary fingers can possess significant velocity, allowing greater interaction with primary fingers compared with high‐mobility ratio flows. Eventually, this interaction can lead to base thinning and the breaking of fingers into separate bubbles. Copyright © 2015 John Wiley & Sons, Ltd.
Late Wenlock carbon isotope excursions and associated conodont fauna in the Podlasie Depression, eastern Poland: a not‐so‐big crisis?
Authors: Jarochowska Emilia , Munnecke Axel
Published: March 2015

The middle Silurian ‘big crisis’ refers to a graptolite extinction event and faunal turnover at the onset of a double‐peaked positive carbon isotope excursion. The crisis has been proposed to affect conodonts, giving rise to a sophisticated palaeoecological model of their stepwise extinction, known as the Mulde Event. However, the impact of the event on conodont faunas outside Gotland and the Silurian Baltic Basin remains unknown. Here, it is examined in the Widowo IG‐1 core (E Poland). The middle Silurian succession in this core represents foreshoal, shoal, and lagoonal settings on a tropical carbonate ramp on the shelf of the Eastern European Craton. Three positive δ13Ccarb excursions have been identified; the two upper excursions correlate with the Mulde isotope anomaly and with two global eustatic regressions. Conodont species proposed to be affected by the extinction event either were not observed or ranged through the extinction interval. Changes in their frequencies are best explained by the sequence stratigraphic architecture of the late Wenlock strata in the Widowo IG‐1 core. The little impact of the ‘big crisis’ may reflect facies homogeneity across the studied interval, supporting the hypothesis that the late Wenlock conodont turnover in epicontinental settings was primarily driven by eustatically controlled facies shifts. Copyright © 2015 John Wiley & Sons, Ltd.
The clinical utility of serum anti‐Müllerian hormone in the follow‐up of ovarian adult‐type granulosa cell tumors—A comparative study with inhibin B
Authors: Färkkilä Anniina , Koskela Sanna , Bryk Saara , Alfthan Henrik , Bützow Ralf , Leminen Arto , Puistola Ulla , Tapanainen Juha S. , Heikinheimo Markku , Anttonen Mikko , Unkila‐Kallio Leila
Published: March 2015

Ovarian adult‐type granulosa cell tumors (AGCTs) require prolonged follow‐up, but evidence regarding the optimal follow‐up marker is lacking. The objective of our study was to validate the clinical usefulness of serum anti‐Müllerian hormone (AMH) and the current marker inhibin B as single and combined markers of AGCTs. We conducted a longitudinal, partially prospective cohort study of 123 premenopausal and postmenopausal AGCT patients with a median follow‐up time of 10.5 years (range 0.3–50.0 years). Serum AMH and inhibin B levels were measured from 560 pretreatment and follow‐up serum samples by using immunoenzymometric assays. We found that serum AMH and inhibin B levels were significantly elevated in patients with primary or recurrent AGCTs. The levels of both markers positively correlated to tumor size (p < 0.05). AMH and inhibin B performed similarly in receiving operator characteristic analyses; area under the curve (AUC) values were 0.92 [95% confidence interval (CI) 0.88–0.95] for AMH, and 0.94 (95% CI 0.90–0.96) for inhibin B. AMH was highly sensitive (92%) and specific (81%) in detecting a macroscopic AGCT. However, in AUC comparison analyses, the combination of the markers was superior to inhibin B alone. In conclusion, serum AMH is a sensitive and specific marker of AGCT, and either AMH or inhibin B can be monitored during follow‐up. However, combining AMH and inhibin B in AGCT patient follow‐up improves the detection of recurrent disease.
The Function of Twisted Gastrulation in Regulating Osteoclast Differentiation is Dependent on BMP Binding
Authors: Huntley Raphael , Davydova Julia , Petryk Anna , Billington Charles J. , Jensen Eric D. , Mansky Kim C. , Gopalakrishnan Rajaram
Published: March 2015

Proper regulation of osteoclast (OCL) function is critical for normal bone homeostasis. Bone morphogenetic protein (BMP) signaling and its regulation have been shown to have direct effects on OCL differentiation and activity. One of the major modulators of BMP signaling in the extracellular space is the secreted protein twisted gastrulation (TWSG1), which can inhibit BMP signaling and OCL differentiation. In this study we examine specific N‐terminal regions of TWSG1 protein that have been previously proposed as BMP binding sites to determine whether TWSG1 binding to BMPs is required for its inhibitory effects on OCLs. We demonstrate that overexpression of wild type TWSG1 suppresses osteoclastogenesis, while overexpression of mutant TWSG1 proteins (W66A and N80Q/N146Q mutants), which cannot bind BMPs, leads to increased BMP signaling, enhanced osteoclastogenesis, increased resorptive activity, and expression of OCL‐specific genes. Our results show that BMP binding is required for TWSG1‐mediated inhibition of OCL formation and function, and validate the critical functional regions within the TWSG1 protein for these interactions. J. Cell. Biochem. 116: 2239–2246, 2015. © 2015 Wiley Periodicals, Inc.
Silver oxide‐containing hydroxyapatite coating supports osteoblast function and enhances implant anchorage strength in rat femur
Authors: Eto Shuichi , Miyamoto Hiroshi , Shobuike Takeo , Noda Iwao , Akiyama Takayuki , Tsukamoto Masatsugu , Ueno Masaya , Someya Shinsuke , Kawano Shunsuke , Sonohata Motoki , Mawatari Masaaki
Published: March 2015

Antibacterial silver with hydroxyapatite (Ag–HA) is a promising coating material for imparting antibacterial properties to implants. We previously reported that 3% (w/w) silver with HA (3% Ag–HA) has both antibacterial activity and osteoconductivity. In this study, we investigated the effects of Ag–HA on the in vitro osteoblast function and the in vivo anchorage strength and osteoconductivity of implants. Production of the osteoblast marker alkaline phosphatase, but not cytotoxicity, was observed in cells of the osteoblast cell line MC3T3‐E1 cultured on the 3% Ag–HA‐coated surface. These results were similar to those observed with silver‐free HA coating. In contrast, a significant high level of cytotoxicity was observed when the cells were cultured on a 50% Ag–HA‐coated surface. The anchorage strength of implants inserted into the femur of Sprague–Dawley (SD) rats was enhanced by coating the implants with 3% Ag–HA. On the 3% Ag–HA‐coated surface, both metaphyseal and diaphyseal areas were largely covered with new bone and had adequate osteoconductivity. These results suggest that 3% Ag–HA, like conventional HA, promotes osteogenesis by supporting osteoblast viability and function and thereby contributes to sufficient anchorage strength of implants. Application of 3% Ag–HA, which combines the osteoconductivity of HA and the antibacterial activity of silver, to prosthetic joints will help prevent postoperative infections. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1391–1397, 2015.
Combined free flaps with arteriovenous loops for reconstruction of extensive thoracic defects after sternal osteomyelitis
Authors: Taeger Christian D. , Horch Raymund E. , Arkudas Andreas , Schmitz Marweh , Stübinger Axel , Lang Werner , Meyer Alexander , Seitz Timo , Weyand Michael , Beier Justus P.
Published: March 2015

Background

Various local flaps have been described for patients suffering from sternal osteomyelitis and are regarded as a standard procedure for defect reconstruction. In contrast, the use of microsurgical free flaps has been reported anecdotally only. We present our experiences with the combination of an arteriovenous loop and a free flap transfer in defects larger than half of the sternum.

Methods

Between January 2012 and October 2014, eight patients with a mean age of 68 years who suffered from extensive deep sternal osteomyelitis were operated in a consecutive series. After radical surgical debridement, the defect size comprised all three thirds of the sternum. Defect reconstruction was achieved by means of free flap transplantation using the vastus lateralis myocutaneous flap, rectus abdominis, and bipedicled latissimus dorsi/parascapular flap. As local recipient vessels were depleted in all patients, the pedicle of the flap was anastomosed to a high‐flow and short‐length subclavian arteriovenous loop as recipient vessel in all cases.

Results

The immediate postoperative course in all patients was uneventful despite one axonal injury to the femoral nerve at the donor site. There was no partial or total flap loss. During a mean follow‐up of 9 months, one patient suffered from a local infection at the donor site. In all patients, a successful defect reconstruction could be achieved.

Conclusion

Depletion of local recipient vessels as an obstacle for free flap reconstruction can be overcome by creating an arteriovenous loop. Even extensive defects are adequate for defect reconstruction using a single or, in extreme cases, bipedicled free flap. © 2015 Wiley Periodicals, Inc. Microsurgery 36:121–127, 2016.
Simultaneous quasi‐optimal convergence rates in FEM‐BEM coupling
Authors: Melenk J. M. , Praetorius D. , Wohlmuth B.
Published: March 2015

S. Nicaise We consider the symmetric finite element–boundary element coupling that connects two linear elliptic second‐order partial differential equations posed in a bounded domain Ω and its complement, where the exterior problem is restated as an integral equation on the coupling boundary Γ = ∂Ω. Under the assumption that the corresponding transmission problem admits a shift theorem for data in H−1 + s,s∈[0,s0],s0>1/2, we analyze the discretization by piecewise polynomials of degree k for the domain variable and piecewise polynomials of degree k − 1 for the flux variable on the coupling boundary. Given sufficient regularity, we show that (up to logarithmic factors) the optimal convergence O(hk + 1/2) in the H−1/2(Γ)‐norm is obtained for the flux variable, whereas classical arguments by Céa‐type quasi‐optimality and standard approximation results provide only O(hk) for the overall error in the natural product norm on H1(Ω) × H−1/2(Γ). Copyright © 2015 John Wiley & Sons, Ltd.
Analysis of spatial/polarization diversity using a broadband slot‐coupled patch antenna for the WLAN 802.11A/B/G/N access point
Authors: Yeom Insu , Kim Hyungrak , Jung Jihak , Jung Chang Won
Published: March 2015

A broad dual‐band slot‐coupled patch antenna is proposed for the wireless local area network band. The basic antenna element consists of two radiators on three layers. To enhance the bandwidth, a coupled feeding was used in the first radiator, and a parasitic patch was used in the second radiator. The peak gain of the single antenna element was more than 6 dBi at 2.4 GHz and more than 8 dBi at 5 GHz. We simulated and measured the extended antenna to four elements using a common reflector, and the spatial and polarization diversity of the proposed antenna were analyzed according to the isolation and the diversity gain. The isolation is below −15 dB at the operating frequency when the distance between the proposed antennas is more than 0.67λ (80 mm). The orthogonal polarization of the proposed antenna obviously improves the performance of the diversity antenna system. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1042–1048, 2015
Acrylic substrate based low profile wearable button antenna with FSS layer for WLAN and Wi‐Fi applications
Authors: Mandal Bappaditya , Chatterjee Ayan , Parui Susanta Kumar
Published: March 2015

In this letter, a low profile circularly polarized wearable antenna with the appearance of a button on clothing for Wi‐Fi and WLAN applications is presented. The radiating elements of the antenna are made of copper sheet while a transparent acrylic fiber sheet material is used as substrate and fed by a coaxial line through the ground plane. The proposed antenna is simulated by Ansoft high frequency structure synthesis finite element method‐based (HFSS FEM)‐based EM simulator and has been optimized to operate within the Wi‐Fi and WLAN frequency bands (5250–5850 MHz) with center frequency of 5.25 GHz. A split ring‐shaped slot‐based frequency selective surface (FSS) is designed to enhance the gain of the proposed antenna. The peak gain of the antenna is found to increase from the conventional antenna gain of 2.1 to 5.1 dBi with the superstrate along with a bandwidth enhancement of 290 MHz. The composite FSS antenna is fabricated and the maximum measured gain of 5.1 dBi matches well with theoretical value. The antenna gets miniaturized around 34% by the slits with its circular polarization characteristic well maintained. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1033–1038, 2015
Tri‐band HIS backed spiral antenna for wireless LAN applications
Authors: Mohamad Sarah , Cahill Robert , Fusco Vincent
Published: March 2015

This study reports the performance of an Archimedean spiral antenna, which exhibits unidirectional circularly polarized radiation patterns with a peak gain >8 dBic in the lower (2.4–2.485 GHz) and upper (5.15–5.35 and 5.725–5.875 GHz) Wireless local area network frequency bands. The required backlobe suppression and impedance match are obtained by placing a multiresonant high impedance surface (HIS) in close proximity to the radiating aperture. Simulated and measured radiation patterns are shown at the center frequency of all three channels and a comparison of the key performance metrics is made with free space and metal backed antenna arrangements to demonstrate the enhancements which are attributed to the HIS reflector. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1116–1121, 2015
A new multipassband filter with multiple transmission zeros based on quarter‐wavelength resonators in wireless communication systems
Authors: Cao Xin , Tang Zongxi , Wang Fei , Wu Yunqiu , Zhang Biao
Published: March 2015

In this article, a new multipassband filter with multiple transmission zeros (TZs) based on quarter‐wavelength resonators (QWRs) is proposed. Three pairs of QWRs are utilized to produce three passbands and three TZs, and the center frequencies of the passbands can be flexibly controlled by changing the length and width of the corresponding resonators without major influence on the other passbands. It is proved from the simulated and measured results that the proposed filter has some excellent properties such as low in‐band insertion loss, great out‐band rejection and compact size. The designed filter has the working frequencies of 1.9 GHz (Global System for Mobile Communication), 2.6 GHz (4G Communication), and 5.2 GHz (Worldwide Interoperability for Microwave Access) and can be applied in the multiprotocol wireless communication systems. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1105–1107, 2015