bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Characterization of Sulfonated Poly‐(styrene‐co‐acrylic acid) for Applications as Pronton Exchange Membranes
Authors: Da Silva Luciano , Pedrosa Renato P. , Coelho Fernanda , Vieira Luana F. , Benavides Roberto , Dal‐Bó Alexandre G. , Frizon Tiago E. , Paula Marcos M. S. 
Published: September 2014

SummaryPolymeric membranes were prepared using the mass copolymerization of styrene/acrylic acid (St/AA) at 90/10, 92/8 and 94/6 ratios. Divinyl benzene (DVB) was also added at concentrations of 0.1 and 0.001% weight for each St/AA ratio. The obtained copolymers were sulfonated by treating the materials with concentrated sulfuric acid for 0, 30 and 85 minutes to enhance their ion exchange capacities. The materials were characterized by Fourier transform infrared spectroscopy (FTIR), thermal analysis by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), cross‐linking level by gel percentage and acidity through sodium hydroxide titration. The FTIR spectra of the membranes before sulfonation showed the existence of traditional bands that corresponded to the polymer components; some homopolymer main bands were lost, whereas two new bands appeared during the copolymerization reaction. The TGA analyses showed a higher decomposition temperature for the DVB cross‐linked membranes, while DSC did not provide much information due to the hygroscopic nature of the membranes. The gel percentage was effectively related to the DVB level. The membranes acidity increased with increasing acrylic acid content, sulfonation time and DVB percentage; however, the acidic values are highly dependent on the solubility of the materials.
Chemistry Modification of PMMA‐g‐PEG copolymer
Authors: Rosa Juliana dos Santos , Silveira Benila Maria , Novack Kátia Monteiro , dos Santos Viviane Martins Rebello , de Moraes Teixeira Leonardo César 
Published: September 2014

SummaryCopolymers are polymers consisting of different repeat units and their production is usually motivated by the changing of polymers properties. An important application are the transportation of drugs within the organism with the aim of controlling the release of the substance. The synthesis of these new copolymers is based on simple semi‐synthesis and low cost. The synthetic routes are based on the interaction of the graft copolymer (PMMA‐g‐PEG) with a variety of reagents such as acetic anhydride, acetic acid, methyl iodide, sulfuric acid and hydrochloric acid. The products from these reactions of esterification, methylation, acetylation and halogenation will be characterized by Fourier‐transforminfrared spectroscopy (FTIR). The use of this technique allowed us to detect the main absorption bands related to the CO bonds, C‐Cl, R‐COOR and CO, thus confirming the efficiency of modification reactions of the graft copolymer chain.
Characterization of Mechanical and Thermal Properties of Poly(ethylene‐co‐vinyl acetate) with Differents Bentonites
Authors: Morita Reinaldo Yoshio , Kloss Juliana Regina , Barbosa Ronilson Vasconcelos 
Published: September 2014

SummaryIn this study, poly(ethylene‐co‐vinyl acetate) (EVA) with different organophilic bentonites were prepared by melt‐blended and evaluated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and the tensile properties. The results showed that the modification of bentonite with the two different surfactants presented distinct thermal and tensile behaviors of the samples containing natural bentonite. Both modifiers acted on the compatibility of the filler with the polymer matrix, obtaining injected‐specimens that were visibly homogeneous. The samples containing the Cloisite® bentonite modified with ammonium salt‐free surfactant (eBI‐AM) presented a different behavior from the others, in that increased crystallinity, which was verified through DSC, due to the nucleating effect of the filler influenced the flexible character of the EVA materials, thus increasing the rigidity and decreasing elongation. Therefore, it was of utmost importance the use and the proposal of an ammonium salt‐free modifier due to the low thermal stability that are caused by them in polymer/organophilic bentonite, as it has already been reported in the literature.
Reduced alpha‐synuclein in cerebrospinal fluid in synucleinopathies: Evidence from a meta‐analysis
Authors: Sako Wataru , Murakami Nagahisa , Izumi Yuishin , Kaji Ryuji 
Published: September 2014

AbstractAlpha‐synuclein plays a key role in the pathology of synucleinopathies including Parkinson's disease (PD) and multiple system atrophy (MSA). However, whether alpha‐synuclein level in cerebrospinal fluid (CSF) could distinguish synucleinopathies from progressive supranuclear palsy (PSP) is still a contentious issue. A comprehensive literature search yielded nine eligible studies. We expressed the between‐group difference of the concentration of alpha‐synuclein in CSF as the standardized mean difference. The proportion of variation attributable to heterogeneity was computed and expressed as I2. Nine studies involved 537 controls, 843 PD, 130 MSA, and 98 PSP patients. The overall effect of PD on alpha‐synuclein in CSF was significantly different from normal control or disease control (standardized mean difference = –0.67, P < 0.00001). These studies were heterogeneous (I2 = 40%). Alpha‐synuclein in CSF in MSA was significantly reduced relative to controls with heterogeneous studies (standardized mean difference = –0.75, P < 0.0001; I2 = 62%). In contrast, no significant difference of alpha‐synuclein in CSF was observed between PSP and controls with heterogeneous studies (standardized mean difference = –0.28, P = 0.13; I2 = 53%). Alpha‐synuclein in CSF was significantly reduced in synucleinopathies compared with PSP (“PD vs. PSP”: standardized mean difference = –0.38, P = 0.001; “MSA vs. PSP”: standardized mean difference = –0.66, P < 0.00001). The included studies were homogeneous (I2 = 0%). Our study showed that alpha‐synuclein levels in CSF in synucleinopathies was significantly lower than in PSP. This finding provides insights into the pathophysiological difference between synucleinopathies and PSP as well as possibility of development of a tool for differential diagnosis between MSA and PSP using enzyme‐linked immunosorbent assay (ELISA) and similar methods. © 2014 International Parkinson and Movement Disorder Society
The increasing incidence of foetal echogenic congenital lung malformations: an observational study
Authors: Stocker Linden J. , Wellesley Diana G. , Stanton Michael P. , Parasuraman Rajeswari , Howe David T. 
Published: September 2014

AbstractObjectivesThe aim of this study was to investigate the incidence of congenital lung malformations over the past 19 years. Congenital lung malformations (CLM) are a heterogeneous group of lung abnormalities. The antenatal diagnosis is important for foetal and neonatal management but there have been no studies examining whether the reported incidence of this abnormality is constant.MethodsA retrospective cross‐sectional study of cases identified from the Wessex Antenatally Detected Anomalies (WANDA) register 1994–2012.ResultsOne hundred and thirty‐three cases of CLM in 524 372 live and stillbirths were identified. All but seven were identified on antenatal ultrasound.During the early registry (1994–1998) the average incidence of CLM was 1.27 per 10 000 births. By the last 4 years (2008–2012) this had risen to 4.15 per 10 000 births, with a progressive increase during the intervening years.ConclusionThere was over a three‐fold increase in the antenatally detected CLM in the Wessex region 1994–2012. Comparison with the antenatal detection of diaphragmatic hernia suggests that this is a true rise in incidence rather than an artefactual increase due to increased antenatal recognition secondary to improved ultrasound resolution and operator experience. These results have clinical and cost implications for practitioners of foetal medicine, neonatology and paediatric surgery services. © 2014 John Wiley & Sons, Ltd.
Use of solution crystallization analysis by laser light scattering for studying the solution crystallization of various Ziegler–Natta‐catalysed polypropylenes
Authors: Amer Ismael , van Reenen Albert , Brand Margaretha 
Published: September 2014

AbstractSolution crystallization analysis by laser light scattering (SCALLS) involves the observation of the scattering of diode mercury laser lamp light after it passes through a polymer solution. An increase in turbidity occurs when the hot polymer solution is cooled and the polymer starts to crystallize out of solution. This causes a decrease in the amount of laser light that can pass through the solution and an increase in the amount of scattered light. The reverse of this process leads to the turbidity decreasing with an increase in temperature. According to this concept, it is possible to follow the solution crystallization of various polypropylenes under controlled cooling. In this study, SCALLS was able to differentiate between different isotactic and syndiotactic polypropylenes with similar chemical structures, but different tacticity and molecular weights. Furthermore, SCALLS provided good crystallization information that is similar to that from crystallization analysis fractionation and temperature rising elution fractionation. In addition, SCALLS can be used as a quantitative tool for the measurement of weight fractions during dissolution. © 2014 Society of Chemical Industry
An Evaluation of the Stream Simulation Culvert Design Method in Washington State
Authors: Barnard R. J. , Yokers S. , Nagygyor A. , Quinn T. 
Published: September 2014

AbstractStream simulation has become an increasingly common culvert design method around the world. It is based on the assumption that geologic and hydraulic conditions in natural channels define passage characteristics for migrating fish and that water crossing structures that imitate these conditions can then achieve those same passage characteristics. This study expands on an initial evaluation of 19 culverts in 2003 to 50 culverts and includes methods and analyses comparing hydraulic characteristics based on cross sections, profile variation, and bed texture between each culvert and its paired reference reach situated in an adjacent section of the natural channel of each stream. Taken as a group, these culverts simulate bed texture, 100‐year recurrence interval flood velocity and 2‐year flood width but did not simulate thalweg complexity or other hydraulic metrics. Culvert span, relative to the bankfull width of the stream, does not by itself determine whether the culvert simulates the reference reach. Of the 50 culverts, many of which experienced record floods, only one showed significant bed degradation. Copyright © 2014 John Wiley & Sons, Ltd.
Application‐specific hybrid symmetric design of key pre‐distribution for wireless sensor networks
Authors: Dargahi Tooska , Javadi Hamid H. S. , Hosseinzadeh Mehdi 
Published: September 2014

AbstractWireless sensor networks have been established for a wide range of applications in adversarial environments, which makes secure communication between sensor nodes a challenging issue. To achieve high level of security, each pair of nodes must share a secret key in order to communicate with each other. Because of the random deployment of sensors, a set of keys must be pre‐distributed, so that each sensor node is assigned a set of keys from a key pool before the deployment. The keys stored in each node must be carefully selected to increase the probability of key share between two neighboring nodes. In this paper, we consider a hybrid key pre‐distribution scheme based on the balanced incomplete block design. We present a new approach for choosing key pool in the hybrid symmetric design that improves the connectivity and scalability of the network. We also introduce an extension to the proposed approach to detract memory usage and improve resilience. Experimental results verify the performance and applicability of our approach. Copyright © 2014 John Wiley & Sons, Ltd.
The influence of Argonaute proteins on alternative RNA splicing
Authors: Batsché Eric , Ameyar‐Zazoua Maya 
Published: September 2014

Alternative splicing of precursor RNAs is an important process in multicellular species because it impacts several aspects of gene expression: from the increase of protein repertoire to the level of expression. A large body of evidences demonstrates that factors regulating chromatin and transcription impact the outcomes of alternative splicing. Argonaute (AGO) proteins were known to play key roles in the regulation of gene expression at the post‐transcriptional level. More recently, their role in the nucleus of human somatic cells has emerged. Here, we will discuss some of the nuclear functions of AGO, with special emphasis on alternative splicing. The AGO‐mediated modulation of alternative splicing is based on several properties of these proteins: their binding to transcripts on chromatin and their interactions with many proteins, especially histone tail‐modifying enzymes, HP1γ and splicing factors. AGO proteins may favor a decrease in the RNA‐polymerase II kinetics at actively transcribed genes leading to the modulation of alternative splicing decisions. They could also influence alternative splicing through their interaction with core components of the splicing machinery and several splicing factors. We will discuss the modes of AGO recruitment on chromatin at active genes. We suggest that long intragenic antisense transcripts (lincRNA) might be an important feature of genes containing splicing events regulated by AGO. WIREs RNA 2015, 6:141–156. doi: 10.1002/wrna.1264This article is categorized under:

RNA Processing > Splicing Regulation/Alternative Splicing
Regulatory RNAs/RNAi/Riboswitches > RNAi: Mechanisms of Action
Expansion wave diffraction over a 90 degree corner
Authors: Mahomed Irshaad , Skews Beric W. 
Published: September 2014

AbstractThe diffraction of an initially one-dimensional plane expansion wave over a 90° corner was explored using experiment and numerical simulation. Unlike studies of shock diffraction, expansion wave diffraction has hardly been documented previously. The planar expansion wave was produced in a shock tube by bursting a diaphragm. Two independent parameters were identified for study: (i) the initial diaphragm shock tube pressure ratio, which determines the strength (pressure ratio) of the expansion, and (ii) the position of the diaphragm from the apex of the 90° corner, which determines the width of the wave. The experimentation only considered variation in the shock tube pressure ratio whereas the simulation varied both parameters. A Navier–Stokes solver with Menter’s shear stress transport$\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}k\mbox{--}\omega $turbulence model was found to adequately model the overall flow field. A number of major flow features were identified occurring in the vicinity of the corner. These were: a shear layer that originated by flow separation at the apex of the corner; a vortex within a separation bubble that remained attached to the wall, in sharp contrast to what happens in the shock wave diffraction case, where the vortex convects downstream; and a reflected compression wave arising from perturbation signals generated by the diffraction. For a narrow-width expansion wave existing prior to diffraction, the reflected compression wave steepens into an outwardly propagating, weak cylindrical shock wave. Regions of supersonic flow are identified surrounding the bubble and can extend downstream depending on the pressure ratio. Another major flow feature identified in some cases was an oblique shock located near the separation bubble. A large wake region is evident immediately downstream of the bubble and appears to consist of two distinct layers. The experimental results showed large-scale turbulent structures within the separation bubble, and shear layer instability and vortex shedding from the separation bubble were also evident.
The Mesozoic–Cenozoic tectonic evolution of the New Siberian Islands, NE Russia
Authors: BRANDES CHRISTIAN , PIEPJOHN KARSTEN , FRANKE DIETER , SOBOLEV NIKOLAY , GAEDICKE CHRISTOPH 
Published: September 2014

AbstractOn the New Siberian Islands the rocks of the east Russian Arctic shelf are exposed and allow an assessment of the structural evolution of the region. Tectonic fabrics provide evidence of three palaeo-shortening directions (NE–SW, WNW–ESE and NNW–SSE to NNE–SSW) and one set of palaeo-extension directions revealed a NE–SW to NNE–SSW direction. The contractional deformation is most likely the expression of the Cretaceous formation of the South Anyui fold–thrust belt. The NE–SW shortening is the most prominent tectonic phase in the study area. The WNW–ESE and NNW–SSE to NNE–SSW-oriented palaeo-shortening directions are also most likely related to fold belt formation; the latter might also have resulted from a bend in the suture zone. The younger Cenozoic NE–SW to NNE–SSW extensional direction is interpreted as a consequence of rifting in the Laptev Sea.
Universality in numerical computations with random data
Authors: Deift Percy A. , Menon Govind , Olver Sheehan , Trogdon Thomas 
Published: September 2014

SignificanceUniversal fluctuations are shown to exist when well-known and widely used numerical algorithms are applied with random data. Similar universal behavior is shown in stochastic algorithms and also in an algorithm that models neural computation. The question of whether universality is present in all, or nearly all, computation is raised.
Structural insights into the role of iron–histidine bond cleavage in nitric oxide-induced activation of H-NOX gas sensor proteins
Authors: Herzik Mark A. , Jonnalagadda Rohan , Kuriyan John , Marletta Michael A. 
Published: September 2014

Significance
Nitric oxide (NO) influences diverse biological processes, ranging from vasodilation in mammals to communal behavior in bacteria. Heme-nitric oxide/oxygen (H-NOX) binding domains, a recently discovered family of heme-based gas sensor proteins, have been implicated as regulators of these processes. Crucial to NO-dependent activation of H-NOX proteins is rupture of the heme–histidine bond and formation of a five-coordinate NO complex. To delineate the molecular details of NO binding, high-resolution crystal structures of a bacterial H-NOX protein in the unligated and intermediate six- and five-coordinate NO-bound states are reported. From these structures, it is evident that NO-induced scission of the heme–histidine bond elicits a pronounced conformational change in the protein as a result of structural rearrangements in the heme pocket.
Crystal structure of class III chitinase from pomegranate provides the insight into its metal storage capacity
Authors: Masuda Taro , Zhao Guanghua , Mikami Bunzo 
Published: September 2014

Abstract
Chitinase hydrolyzes the β-1,4-glycosidic bond in chitin. In higher plants, this enzyme has been regarded as a pathogenesis-related protein. Recently, we identified a class III chitinase, which functions as a calcium storage protein in pomegranate (Punica granatum) seed (PSC, pomegranate seed chitinase). Here, we solved a crystal structure of PSC at 1.6 Å resolution. Although its overall structure, including the structure of catalytic site and non-proline cis-peptides, was closely similar to those of other class III chitinases, PSC had some unique structural characteristics. First, there were some metal-binding sites with coordinated water molecules on the surface of PSC. Second, many unconserved aspartate residues were present in the PSC sequence which rendered the surface of PSC negatively charged. This acidic electrostatic property is in contrast to that of hevamine, well-characterized plant class III chitinase, which has rather a positively charged surface. Thus, the crystal structure provides a clue for metal association property of PSC.
Stereoselective syntheses of cryptocarya diacetate and all its stereoisomers in optically pure forms
Authors: Yamauchi Satoshi , Nishimura Hiroki , Nishiwaki Hisashi 
Published: September 2014

Abstract
Cryptocarya diacetate and each of its stereoisomers were stereoselectively synthesized in 8–16 steps. One of the three chiral carbons was converted from the chiral center of a yeast-reduction product. The other two chiral carbons were constructed by employing stereoselective allylation and syn-and anti-1,3-reductions. The enantiomeric excesses of the synthesized cryptocarya diacetate and its stereoisomers were determined to be more than 99%ee using a chiral column.
PHI-DAC: protein homology database through dihedral angle conservation
Authors: Maatuk Noa , Glantz-Gashai Yitav , Rotman Maya , Baydany Meirav , Fonar Gennadiy , Shechvitz Amir , Shemer Karin , Peleg Aviva , Reuveni Eli , Samson Abraham O. 
Published: September 2014

Abstract
Finding related conformations in the Protein Data Bank is essential in many areas of bioscience. To assist this task, we designed a dihedral angle database for searching protein segment homologs. The search engine relies on encoding of the protein coordinates into text characters representing amino acid sequence, φ and ψ dihedral angles. The search engine is advantageous owing to its high speed and interactive nature and is expected to assist scientists in discovering conformation homologs and evolutionary kinship. The search engine is fast, with query times lasting a few seconds, and freely available at http://tarshish.md.biu.ac.il/∼samsona
Contact: avraham.samson@biu.ac.il
Supplementary information: Supplementary data are available at Bioinformatics online.
METAINTER: meta-analysis of multiple regression models in genome-wide association studies
Authors: Vaitsiakhovich Tatsiana , Drichel Dmitriy , Herold Christine , Lacour André , Becker Tim 
Published: September 2014

AbstractMotivation : Meta-analysis of summary statistics is an essential approach to guarantee the success of genome-wide association studies (GWAS). Application of the fixed or random effects model to single-marker association tests is a standard practice. More complex methods of meta-analysis involving multiple parameters have not been used frequently, a gap that could be explained by the lack of a respective meta-analysis pipeline. Meta-analysis based on combining p -values can be applied to any association test. However, to be powerful, meta-analysis methods for high-dimensional models should incorporate additional information such as study-specific properties of parameter estimates, their effect directions, standard errors and covariance structure.Results : We modified ‘method for the synthesis of linear regression slopes’ recently proposed in the educational sciences to the case of multiple logistic regression, and implemented it in a meta-analysis tool called METAINTER. The software handles models with an arbitrary number of parameters, and can directly be applied to analyze the results of single-SNP tests, global haplotype tests, tests for and under gene–gene or gene–environment interaction. Via simulations for two-single nucleotide polymorphisms (SNP) models we have shown that the proposed meta-analysis method has correct type I error rate. Moreover, power estimates come close to that of the joint analysis of the entire sample. We conducted a real data analysis of six GWAS of type 2 diabetes, available from dbGaP ( http://www.ncbi.nlm.nih.gov/gap ). For each study, a genome-wide interaction analysis of all SNP pairs was performed by logistic regression tests. The results were then meta-analyzed with METAINTER.Availability : The software is freely available and distributed under the conditions specified on http://metainter.meb.uni-bonn.deContact : vait@imbie.meb.uni-bonn.deSupplementary information: Supplementary data are available at Bioinformatics online.