bluuebunny/crossref_metadata_2025_split huggingface dataset:
Women's experience of termination of pregnancy for fetal anomaly: effects of socio‐political evolutions in France
Authors: Mirlesse Veronique , Perrotte Frederique , Kieffer François , Ville Isabelle 
Published: July 2011

AbstractObjectiveTo analyse the experiences of women facing a termination of pregnancy for fetal anomaly (TOPFA) in relation to decisional aspects, attitudes towards the fetus' body and the effects of postpartum depression. The method is based on a two‐stage questionnaire given to 120 women who underwent a TOPFA between 2005 and 2006 in a Parisian Prenatal Diagnosis Department and compared to a similar study carried out in 1999 in the same department.ResultsIn 2005, 68/120 women (57%) compared to 32/103 (32%) in 99 (p < 0.001) believed that the decision of pregnancy termination belongs to couples and doctors together. However, in advanced pregnancy or fetal pathology related to mental deficiency, a higher proportion of women believe that the decision should belong to the parents alone. In 2005, 66% of the women (78/118) compared to (42/103) 41% in 1999 (p < 0.001), chose to see their fetus after the termination. Postpartum depression score was positive in one third of the 2005 series and higher in younger women.ConclusionOur study suggests that women differentiate between various decision‐making actors depending on the type of pregnancy termination. The differences observed between 1999 and 2005 suggest a strong interaction between women's experiences, legislation and practices. Copyright © 2011 John Wiley & Sons, Ltd.
Risk of falls associated with antihypertensive medication: self‐controlled case series
Authors: Gribbin Jonathan , Hubbard Richard , Gladman John , Smith Chris , Lewis Sarah 
Published: July 2011

ABSTRACTPurposeTo quantify the possible role of confounding in our earlier estimates of the risk of falls amongst older people who have been prescribed antihypertensives.MethodsSelf‐controlled case series analysis of 9862 individuals older than 60 years of age with a first fall recorded between years 2003 and 2006 and at least 12 months of recorded history before the first fall, taken from 386 UK general practices contributing data to The Health Improvement Network primary care database. Conditional Poisson regression to estimate incidence rate ratios for periods of exposure and non‐exposure, adjusting for the effect of age.ResultsIncidence rate ratio of first fall in days 1–21 of the first episode of thiazide prescription is 2.80 (95%CI 1.7–4.57). For beta‐blockers, the rate ratio in day 22 onwards is 1.23 (95%CI 1.02–1.48) in the very first episode of medication and 1.21 (95%CI 1.02–1.42) in subsequent episodes but is not significant in other periods of exposure. The incidence rate of first falls in day 22 of any episode of calcium channel blocker prescription is 0.75 (95%CI 0.60–0.92).ConclusionsThe study provides evidence that at least some of our earlier estimates were subject to confounding. Nevertheless, thiazide prescription remains associated with an increased risk of first fall, and this effect is strongest in the first 3 weeks of prescription. Our study demonstrates that the case series method provides an effective way to assess the extent of residual confounding in case–control studies. Copyright © 2011 John Wiley & Sons, Ltd.
Preparation and characterization of epoxy resin modified with alkoxysilane‐ functionalized poly(urethane‐imide) by the sol–gel process
Authors: Song Jiangxuan , Chen Guangxin , Ding Yun , Shi Jianjun , Liu Ying , Li Qifang 
Published: July 2011

AbstractThe sol–gel process has been frequently employed for preparation of high performance silica/polymer composites. In this paper, novel sol–gel precursor triethoxysilane‐terminated poly(urethane‐imide) (PUI‐Si), combining the advantages of polyurethane (PU) and polyimide, was synthesized and characterized. Then PUI‐Si was incorporated into the epoxy resin matrix to prepare a series of EP/PUI‐Si organic‐inorganic hybrids through an in situ sol–gel process and crosslinking reactions. The thermal stability of EP/PUI‐Si hybrids was evaluated by thermogravimetric analysis and the results show that the PUI‐Si could significantly improve the thermal properties of epoxy resin. The initial decomposition temperature of composites with 50 wt% PUI‐Si reached 347.1 °C, 157.3 °C higher than that of neat epoxy resin. Furthermore, the tensile strength and breaking elongation can also be clearly improved by adding a suitable amount of PUI‐Si. Similarly, the water contact angle increased to 97.4° with 70 wt% PUI‐Si, showing a hydrophobic surface. The morphology was investigated by transmission electron microscopy and the results reveal that the silica particles are smaller than 20 nm and have a strong interaction with the epoxy resin matrix, resulting in the above‐mentioned high performance properties. Copyright © 2011 Society of Chemical Industry
Sequencing cyclic peptides by multistage mass spectrometry
Authors: Mohimani Hosein , Yang Yu‐Liang , Liu Wei‐Ting , Hsieh Pei‐Wen , Dorrestein Pieter C. , Pevzner Pavel A. 
Published: July 2011

AbstractSome of the most effective antibiotics (e.g. Vancomycin and Daptomycin) are cyclic peptides produced by non‐ribosomal biosynthetic pathways. While hundreds of biomedically important cyclic peptides have been sequenced, the computational techniques for sequencing cyclic peptides are still in their infancy. Previous methods for sequencing peptide antibiotics and other cyclic peptides are based on Nuclear Magnetic Resonance spectroscopy, and require large amount (miligrams) of purified materials that, for most compounds, are not possible to obtain. Recently, development of MS‐based methods has provided some hope for accurate sequencing of cyclic peptides using picograms of materials. In this paper we develop a method for sequencing of cyclic peptides by multistage MS, and show its advantages over single‐stage MS. The method is tested on known and new cyclic peptides from Bacillus brevis, Dianthus superbus and Streptomyces griseus, as well as a new family of cyclic peptides produced by marine bacteria.
The proteome of Mycoplasma pneumoniae, a supposedly “simple” cell
Authors: Catrein Ina , Herrmann Richard 
Published: July 2011

AbstractThis review covers progress in proteome research on Mycoplasma pneumoniae made over the last 5 years. This bacterium is one of the smallest known self‐replicating bacteria. With fewer than 700 proposed proteins, it is well suited to a comprehensive proteome analysis. While all of the proposed genes are transcribed, thus far 620 proteins, about 90% of the predicted proteome, have been identified experimentally. To study the proteome organization of M. pneumoniae, 178 soluble protein complexes were isolated under non‐denaturing conditions by tandem affinity chromatography and their composition determined by SDS‐PAGE and mass spectrometry. The 62 homomultimeric and 116 heteromultimeric protein complexes could be classified according to 12 different COG functional categories. The complexes interacted with each other to some extent, forming larger assemblies. Protein complexes that were large enough and had specific structures (e.g. ribosomes or DNA‐dependent RNA polymerase) were visible and countable in their natural environment by cryo‐electron tomography. In addition to characterization of the soluble complexes, the analysis of the Triton X‐100 insoluble fraction has a major role in the elucidation of the cytoskeleton‐like structure, because by analogy with eukaryotic cells, almost all of the structural proteins involved in its formation, and enriched sub‐cellular structures, can be found in this fraction.
Discrete macromolecular constructs via the Diels–Alder “Click” reaction
Authors: Hizal Gurkan , Tunca Umit , Sanyal Amitav 
Published: July 2011

AbstractFunctional polymeric materials with desired properties can be designed by precise control of macromolecular architectures. Over the recent years, click reactions have enabled efficient synthesis of a variety of polymers with different topologies via efficient polymer–polymer conjugations. While the copper catalyzed Huisgen type (3+2) dipolar cycloaddition between azide and alkyne has been widely used toward this goal, the Diels–Alder (DA) reaction offers an alternative click reaction that allow efficient macromolecular conjugations, oftentimes without the need of any additional reagent or catalyst. This article highlights, with illustrative examples, the power of the DA “click” reaction to efficiently synthesize a variety of different well‐defined macromolecular constructs in a modular fashion. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Alumina additives for fast iron‐mediated AGET ATRP of MMA using onium salt as ligand
Authors: Bai Liangjiu , Zhang Lifen , Zhang Zhengbiao , Zhu Jian , Zhou Nianchen , Cheng Zhenping , Zhu Xiulin 
Published: July 2011

AbstractThree kinds of alumina (acidic, neutral, and basic Al2O3) were effective as additives for the control and rate enhancement of iron‐mediated AGET (activators generated by electron transfer) ATRP (atom transfer radical polymerization) of methyl methacrylate (MMA) in the presence of limited amount of air, using FeCl3·6H2O as the catalyst, tetrabutylammonium bromide or tetra‐n‐butylphosphonium bromide as the ligand, ethyl 2‐bromoisobutyrate as the initiator, and ascorbic acid as the reducing agent. The conversion could be up to 83.9% in the case of basic Al2O3 and 75.3% with neutral Al2O3 only in 13 h, respectively, whereas no polymer could be obtained even in 50 h without additives. The polymers obtained with neutral and basic Al2O3 had controlled molecular weights and low Mw/Mn values (∼1.2). Tacticities of the as‐prepared PMMA in the presence of these three kinds of Al2O3 were consistent with that obtained from conventional free‐radical polymerization of MMA. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Polyisobutylene‐based polyurethanes with unprecedented properties and how they came about
Authors: Kang Jungmee , Erdodi Gabor , Kennedy Joseph P. 
Published: July 2011

AbstractThis highlight concerns the birth, development, and present status of unique polyurethanes consisting of polyisobutylene soft segments and conventional hard segments (PIB‐based PUs) exhibiting unprecedented combinations of mechanical properties and oxidative/hydrolytic/biological stability. Impetus for developments was to improve the rather poor chemical resistance of conventional polyurethanes by replacing their soft segments with polyisobutylene segments. Research started in the 1980s with the synthesis of α,ω‐polyisobutylene diols (HO‐PIB‐OH) by the inifer technique and preparation of PIB‐based PUs, which indeed exhibited outstanding stabilities, however, had poor mechanical properties. Because of cumbersome early techniques and expensive reagents, worldwide research and industrial interest waned and developments went into hibernation. Recent discoveries, including living isobutylene polymerization, improved end‐functionalizations, inexpensive ingredients, and new insight into PU morphology, lead to simple and less expensive synthesis strategies and, consequently, to resumption of fundamental and applied research. Presently, we can produce kilogram quantities of polyurethanes and polyureas with unprecedented combinations of excellent physical–mechanical–environmental–biological and processing properties. This highlight focuses on facts and insights, which occurred since the discovery and shaped developments. These events are worth reviewing and analyzing because they illustrate how contemporary academic research is driven by curiosity (fun) and economic considerations (money). © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Nanocomposites of polyamide‐11 and carbon nanostructures: Development of microstructure and ultimate properties following solution processing
Authors: Mago Gaurav , Kalyon Dilhan M. , Fisher Frank T. 
Published: July 2011

AbstractThere is growing interest in the incorporation of nanoparticles into engineering polymers to improve various functional properties. However, ultimate properties of nanocomposites are affected by a large number of factors including the microstructural distributions that are generated during processing. In this work, polyamide‐11 (PA‐11) (also known as nylon‐11) nanocomposites are generated with carbon nanostructures employing a solution crystallization technique at multiple polymer and nanoparticle concentrations, followed by drying, molding, uniaxial stretching and the analysis of the microstructural distributions and tensile properties of the nanocomposites. The morphology of crystals of PA‐11 encapsulating the nanoparticles changed from nano‐hybrid shish‐kebabs at low polymer concentration (0.02 wt % PA‐11 in solvent) to spherulites at high polymer concentration (10 wt % PA‐11 in solvent). The drawing down of nanocomposite films at draw ratios ranging from 2 to 5 at 100 °C resulted in a shift of the PA‐11 polymorph from the generally‐encountered α phase to the technologically interesting γ phase (which is the crystal phase attributed to the piezoelectric and pyroelectric properties of PA‐11). The drawing down also increased of the tensile modulus and yield stress of the nanocomposite films. In contrast, the α phase was conserved at a drawdown temperature of 150 °C, which was attributed to the resulting smaller normal force, i.e., the normal stress difference and the higher temperature allowing the partial relaxation of some of the macromolecules. These findings illustrate how PA‐11 can be structured in the presence of carbon nanotubes and nanofibers to achieve enhanced functionality, which could broaden the application areas and utility of this polymer. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1311–1321, 2011
Fluid Modeling of the Conversion of Methane into Higher Hydrocarbons in an Atmospheric Pressure Dielectric Barrier Discharge
Authors: De Bie Christophe , Verheyde Bert , Martens Tom , van Dijk Jan , Paulussen Sabine , Bogaerts Annemie 
Published: July 2011

AbstractA one‐dimensional fluid model for a dielectric barrier discharge in methane, used as a chemical reactor for gas conversion, is developed. The model describes the gas phase chemistry governing the conversion process of methane to higher hydrocarbons. The spatially averaged densities of the various plasma species as a function of time are discussed. Besides, the conversion of methane and the yields of the reaction products as a function of the residence time in the reactor are shown and compared with experimental data. Higher hydrocarbons (C2Hy and C3Hy) and hydrogen gas are typically found to be important reaction products. Furthermore, the main underlying reaction pathways are determined.magnified image
Atmospheric Plasma Enhances Wettability and Osteoblast Spreading on Dentin In Vitro: Proof‐of‐Principle
Authors: Koban Ina , Duske Kathrin , Jablonowski Lukasz , Schröder Karsten , Nebe Barbara , Sietmann Rabea , Weltmann Klaus‐Dieter , Hübner Nils‐Olaf , Kramer Axel , Kocher Thomas 
Published: July 2011

AbstractThe medical background of these investigations is periodontal disease which involves progressive loss of the connective tissue and alveolar bone around the teeth. Increased wettability of dentin or bone replacement materials (hydroxyapatite) may be supportive for successful periodontal regeneration. In this in vitro study, we investigated if an atmospheric pressure, non‐thermal plasma process is able to enhance wettability of dentin and hydroxyapatite as well as if increased wettability translates into a higher spreading capacity of osteoblasts. Surface modification was performed with an atmospheric pressure plasma jet on hydroxyapatite, mammoth ivory and human dentin discs. We used three different plasma gas compositions (argon/+0.2%oxygen/+1% oxygen) with 30, 60 or 120 s application time. Water contact angles and cell spreading of MG‐63 osteoblasts were measured before and after plasma treatment. Contact angles of the three investigated materials (dentin, hydroxyapatite and mammoth ivory: 52.00°, 36.00° and 71.00°, respectively) were significantly reduced after 120 s plasma application (13.90° ± 1.70, 0.00° ± 0.00 and 0.00° ± 0.00, respectively). The most effective contact angle reduction was observed after 60 or 120 s application of Ar + 1%O2 plasma. The cell area of osteoblasts grown on dentin treated with Ar + 1%O2 plasma was larger than on untreated dentin surfaces (p < 0.05). The application of atmospheric plasma reduces the contact angle; the altered surface chemistry translates into a superior spreading of osteoblasts on dentin. These results may offer an additional approach to optimise periodontal regeneration.magnified image
Serum‐autoantibodies for discovery of prostate cancer specific biomarkers
Authors: Massoner Petra , Lueking Angelika , Goehler Heike , Höpfner Annabel , Kowald Axel , Kugler Karl G. , Amersdorfer Peter , Horninger Wolfgang , Bartsch Georg , Schulz‐Knappe Peter , Klocker Helmut 
Published: July 2011

AbstractBACKGROUNDThe currently used prostate cancer serum marker has a low cancer specificity and improved diagnostics are needed. Here we evaluated whether autoantibodies are present in sera of prostate cancer patients and whether they are useful diagnostic markers for prostate cancer.METHODSSera from 20 prostate cancer patients and 20 healthy controls were incubated on expression clone arrays containing more than 37,000 recombinant human proteins. Functional annotation clustering of the identified autoantigens was performed using the DAVID database. Autoantigens identified in the prostate cancer group were validated on microarrays using sera of 40 prostate cancer patients, 40 patients with elevated PSA levels but prostate cancer negative biopsies (benign disease), and 40 healthy controls.RESULTSWe detected autoantibodies against 408 different antigens in sera of prostate cancer patients. One hundred seventy‐four of these were exclusively detected in the cancer group compared to the healthy control group. Functional annotation clustering revealed an enrichment of RNA‐associated, cytoskeleton, and nuclear proteins. The autoantibody panel was validated in serum samples of independent prostate cancer patients. Autoantibody profiles discriminated between prostate cancer patients and benign disease patients with an ROC curve AUC of 0.71. TTLL12, a protein recently described to be over‐expressed in prostate cancer, was the highest ranked discrimination autoantigen.CONCLUSIONA variety of autoantibodies were identified in sera of prostate cancer patients and provide a first step towards autoantibody diagnostics. Serum autoantibodies reflect the disease and represent valuable tools not only for prostate cancer, but also for other diseases affecting the immune response. Prostate 72:427–436, 2012. © 2011 Wiley Periodicals, Inc.
Ionic strength dependence of F‐actin and glycolytic enzyme associations: A Brownian dynamics simulations approach
Authors: Forlemu Neville Y. , Njabon Eric N. , Carlson Kristine L. , Schmidt Elizabeth S. , Waingeh Victor F. , Thomasson Kathryn A. 
Published: July 2011

AbstractThe association of glycolytic enzymes with F‐actin is proposed to be one mechanism by which these enzymes are compartmentalized, and, as a result, may possibly play important roles for: regulation of the glycolytic pathway, potential substrate channeling, and increasing glycolytic flux. Historically, in vitro experiments have shown that many enzyme/actin interactions are dependent on ionic strength. Herein, Brownian dynamics (BD) examines how ionic strength impacts the energetics of the association of F‐actin with the glycolytic enzymes: lactate dehydrogenase (LDH), glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), fructose‐1,6‐bisphosphate aldolase (aldolase), and triose phosphate isomerase (TPI). The BD simulations are steered by electrostatics calculated by Poisson‐Boltzmann theory. The BD results confirm experimental observations that the degree of association diminishes as ionic strength increases but also suggest that these interactions are significant, at physiological ionic strengths. Furthermore, BD agrees with experiments that muscle LDH, aldolase, and GAPDH interact significantly with F‐actin whereas TPI does not. BD indicates similarities in binding regions for aldolase and LDH among the different species investigated. Furthermore, the residues responsible for salt bridge formation in stable complexes persist as ionic strength increases. This suggests the importance of the residues determined for these binary complexes and specificity of the interactions. That these interactions are conserved across species, and there appears to be a general trend among the enzymes, support the importance of these enzyme‐F‐actin interactions in creating initial complexes critical for compartmentation. Proteins 2011; © 2011 Wiley‐Liss, Inc.
PackHelix: A tool for helix‐sheet packing during protein structure prediction
Authors: Hu Chengcheng , Koehl Patrice , Max Nelson 
Published: July 2011

AbstractThe three‐dimensional structure of a protein is organized around the packing of its secondary structure elements. Predicting the topology and constructing the geometry of structural motifs involving α‐helices and/or β‐strands are therefore key steps for accurate prediction of protein structure. While many efforts have focused on how to pack helices and on how to sample exhaustively the topologies and geometries of multiple strands forming a β‐sheet in a protein, there has been little progress on generating native‐like packings of helices on sheets. We describe a method that can generate the packing of multiple helices on a given β‐sheet for αβα sandwich type protein folds. This method mines the results of a statistical analysis of the conformations of αβ2 motifs in protein structures to provide input values for the geometric attributes of the packing of a helix on a sheet. It then proceeds with a geometric builder that generates multiple arrangements of the helices on the sheet of interest by sampling through these values and performing consistency checks that guarantee proper loop geometry between the helices and the strands, minimal number of collisions between the helices, and proper formation of a hydrophobic core. The method is implemented as a module of ProteinShop. Our results show that it produces structures that are within 4–6 Å RMSD of the native one, regardless of the number of helices that need to be packed, though this number may increase if the protein has several helices between two consecutive strands in the sequence that pack on the sheet formed by these two strands. Proteins 2011; Published 2011 Wiley‐Liss, Inc.
Vacancy growth and migration dynamics in atomically thin hexagonal boron nitride under electron beam irradiation
Authors: Alem Nasim , Erni Rolf , Kisielowski Christian , Rossell Marta D. , Hartel Peter , Jiang Bin , Gannett Will , Zettl A. 
Published: July 2011

AbstractAtomically thin hexagonal boron nitride (h‐BN) is investigated using aberration‐corrected ultra‐high resolution electron microscopy under 80 kV electron beam. This study focuses on the in situ formation, growth and migration of vacancies in h‐BN. This study also reveals interaction dynamics of edges and vacancies with adatoms and molecules under the electron beam. According to this investigation, boron monovacancies migrate through their second neighbor to reduce the surface energy of the membrane. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)