bluuebunny/crossref_metadata_2025_split huggingface dataset:
Steroid hormone receptors, matrix metalloproteinases, insulin‐like growth factor, and dystroglycans interactions in prostatic diseases in the elderly men
Authors: Hetzl A.C. , Fávaro W.J. , Billis A. , Ferreira U. , Cagnon V.H.A. 
Published: May 2012

AbstractOBJECTIVES: The aim of this study was to evaluate the reactivity of steroid hormone receptors (SHRs), dystroglycans (DGs), matrix metalloproteinases (MMPs), insulin‐like growth factor receptor (IGFR‐1), and laminin (Lam) in both prostatic stromal and epithelial compartments showing different diseases in elderly men. METHODS: Sixty prostatic samples were obtained from 60‐ to 90‐year‐old patients (mean 63 years) with and without prostatic lesions from Hospital of the School of Medicine, State University of Campinas (UNICAMP). The Samples were divided into standard (no lesions); high grade prostatic intraepithelial neoplasia (HGPIN); prostatic cancer (PC); and benign prostatic hyperplasia (BPH) groups. The samples were submitted to immunohistochemistry and Western blotting analyses. Research Ethics Committee of the School of Medicine, University of Campinas/UNICAMP (number 0094.0.146.000‐08). RESULTS: The results showed increased IGFR‐1 and MMPs protein levels in the PC and HGPIN groups. Decreased αDG and βDG protein levels were verified in the PC and HGPIN groups. Androgen receptor (AR) reactivity was similar among all groups. Estrogen receptor α (Erα) immunoreactivity was more intense in the epithelium in the PC and HGPIN groups. Estrogen receptor β (ERβ) immunoreactivity was weak in the epithelium of the HGPIN and PC groups. CONCLUSIONS: To conclude, there was an association among IGFR‐1, MMPs, and SHRs, indicating IGFR‐1 as a target molecule in prostate therapy, considering the IGF proliferative properties. Also, the distinct SHRs reactivities in the lesions in both prostatic compartments indicated different paracrine signals and pointed out the importance of estrogenic pathways in the activation of these disorders. Microsc. Res. Tech. 75:1197–1205, 2012. © 2012 Wiley Periodicals, Inc.
Microcavity plasmonics: strong coupling of photonic cavities and plasmons
Authors: Ameling Ralf , Giessen Harald 
Published: May 2012

AbstractThe understanding of light‐matter interactions at the nanoscale lays the groundwork for many future technologies, applications and materials. The scope of this article is the investigation of coupled photonic‐plasmonic systems consisting of a combination of photonic microcavities and metallic nanostructures. In such systems, it is possible to observe an exceptionally strong coupling between electromagnetic light modes of a resonator and collective electron oscillations (plasmons) in the metal. Furthermore, the results have shown that coupled photonic‐plasmonic structures possess a considerably higher sensitivity to changes in their environment than conventional localized plasmon sensors due to a plasmon excitation phase shift that depends on the environment.
Long‐Chain Polyacetals From Plant Oils
Authors: Chikkali Samir , Stempfle Florian , Mecking Stefan 
Published: May 2012

AbstractPlant oil‐derived α,ω‐diacetals are polycondensated to the novel polyacetals [OCH2O(CH2)y]n (y = 19 and 23) with molecular weight of ca. Mn = 2 × 104 g mol−1. The long methylene sequences provide substantial melt and crystallization temperatures (Tm = 88 °C and Tc = 68 °C for y = 23), and rates of hydrolytic degradation are dramatically lower for the long‐chain polyacetals versus a shorter chain analogue (y = 12) studied for comparison.
Macroscopic diffusivity in concrete determined by computational homogenization
Authors: Nilenius Filip , Larsson Fredrik , Lundgren Karin , Runesson Kenneth 
Published: May 2012

SUMMARYEffective moisture and chloride ion diffusivity coefficients for concrete are determined by computational homogenization, where concrete is modeled on the mesoscale as a heterogenous three‐phase composite material. By imposing moisture and chloride ion gradients on a representative volume element, effective macroscale properties are obtained through finite element analysis. A parametric study of the effects of the ballast content was carried out. The numerical results correspond well with an estimate of the Hashin–Shtrikman type available in the literature. The computational homogenization strategy proposed here also includes the interfacial transition zone, and its influence on the effective diffusivity coefficients is assessed. Copyright © 2012 John Wiley & Sons, Ltd.
On the performance of high‐order finite elements with respect to maximum principles and the nonnegative constraint for diffusion‐type equations
Authors: Payette G.S. , Nakshatrala K.B. , Reddy J.N. 
Published: May 2012

SUMMARYThe main aim of this paper is to document the performance of p‐refinement with respect to maximum principles and the nonnegative constraint. The model problem is steady‐state anisotropic diffusion with decay (which is a second‐order elliptic partial differential equation). We consider the standard single‐field formulation based on the Galerkin formalism and two least squares‐based mixed formulations. We employ Lagrange polynomials with unequal‐spaced points, and polynomials of order p = 1 to p = 10 are used. It is shown that the violation of the nonnegative constraint cannot be overcome with p‐refinement alone for anisotropic diffusion. We shall illustrate the performance of p‐refinement by using several representative problems. The intended outcomes of the paper are twofold. First, this study will caution the users of high‐order approximations about their performance with respect to maximum principles and the nonnegative constraint. Second, this study will help researchers develop new methodologies for enforcing maximum principles and the nonnegative constraint under high‐order approximations. Copyright © 2012 John Wiley & Sons, Ltd.
Polyvinylidene fluoride/poly(ethylene terephthalate) conductive composites for proton exchange membrane fuel cell bipolar plates: Crystallization, structure, and through‐plane electrical resistivity
Authors: Song Jianbin , Mighri Frej , Ajji Abdellah , Lu Chunhua 
Published: May 2012

AbstractPolyvinylidene fluoride/poly(ethylene terephthalate) (PVDF/PET)‐based composites for proton exchange membrane fuel cell bipolar plates (BPs) were prepared at different crystallization temperatures and characterized by X‐ray diffraction, differential scanning calorimetry, and resistivity setup. Composite conductivity was made possible by using a mixture of carbon black (CB) and graphite (GR). To improve composite processability, its viscosity was reduced by adding a small amount of cyclic butylene terephthalate (c‐BT) oligomer and thermoplastic polyolefin elastomer. In the PVDF/PET‐based composite, it was found that PVDF phase could crystallize easily but PET crystallization was difficult. Because of the CB/GR additives, the formed crystals in PVDF/PET phases had a poor perfection degree and showed a lower melting temperature when compared with pure PVDF and PET. It was observed that PET nucleation was accelerated but not that of PVDF. According to through‐plane resistivity results, composite crystallization temperature range was divided into two parts (below/above 170°C), in which a different variation behavior of through‐plane resistivity was observed. It has been proved that the resistivity was mainly governed by the network of CB/GR developed inside the PET phase, and decreasing the crystallinity of PET led to a decrease of through‐plane resistivity, which is desirable for BPs. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Modification of styrene–ethylene/butylene–styrene copolymer microstructure by polystyrene homopolymer and evolution of a cocontinuous blend morphology
Authors: Raha Sumanta , Kao Nhol , Bhattacharya Sati N. 
Published: May 2012

AbstractStyrene–ethylene/butylene–styrene (SEBS) copolymer was blended with the homopolymer polystyrene (hPS) in a counter‐rotating twin‐screw extruder to prepare hPS/SEBS blends. The morphology of the hPS/SEBS blends was studied by environmental scanning electron microscopy (ESEM) and by transmission electron microscopy (TEM). TEM imaging of pure SEBS revealed a microphase‐separated morphology, showing ordered regions or grains where the discrete styrene blocks formed hexagonally packed cylindrical structures within the ethylene/butylene matrix. Blending of small quantities of the homopolymer hPS showed an interesting result. The TEM images of the SEBS‐rich blends revealed that the added hPS was absorbed within the bulk of the SEBS phase resulting in a new SEBS‐rich phase, and the absorbed hPS was found to join the styrene cylinders of pure SEBS thereby modifying its original microstructure. As the hPS concentration in the blends was increased further, the ESEM and TEM images showed that the excess homopolymer hPS phase separated, forming a cocontinuous morphology with the hPS‐modified SEBS‐rich phases. Linear viscoelastic tests on the SEBS‐rich blends also revealed the existence of a synergistic effect, showing increased elastic behavior compared with that of pure SEBS. Small‐angle X‐ray scattering results showed an additional periodicity in the SEBS‐rich phase because of the modification of the SEBS microstructure by hPS. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Synthesis and characterization of Ti(Tbse)2 and its application as a catalyst for ROP of rac‐Lactide
Authors: Hu Chengbo , Wang Yuanliang , Xiang Hongzhao , Fu Ya , Fu Chunhua , Sun Jiaoxia , Xiang Yan , Ruan Changshun , Li Xiang 
Published: May 2012

AbstractA novel bis(3,5‐di‐ tert‐butylsalicylaldehyde‐co‐ethanolamine) titanium(IV) complex (Ti(Tbse)2) was synthesized and structurally characterized. The X‐ray diffraction results showed that the titanium ion was bonded with two 3,5‐di‐tert‐butylsalicylaldehyde‐co‐ethanolamine ligands (Tbse ligands) in O,N,O‐tridentate mode. Experimental results revealed that the Ti(Tbse)2 complex could efficiently catalyze the ring‐opening polymerization (ROP) of rac‐lactide and showed a well‐controlled manner at 160 °C, and the polymers obtained had a controlled molecular weight and low polydispersity indices. Kinetic studies showed that the polymerization reaction was second order in monomer concentration and first order in catalyst concentration, and the apparent activation energy (Ea = 77.0 kJ mol−1) and frequency factor (A = 3.3 × 1011) were obtained according to the Arrhenius equation. 13C nuclear magnetic resonance spectra and thermogravimetric and differential scanning calorimetry analysis indicated that the polylactide was essentially a heterotactic and thermally stable polymer. Copyright © 2012 Society of Chemical Industry
Degradable and chemically recyclable epoxy resins containing acetal linkages: Synthesis, properties, and application for carbon fiber‐reinforced plastics
Authors: Hashimoto Tamotsu , Meiji Hiroyuki , Urushisaki Michio , Sakaguchi Toshikazu , Kawabe Kazumasa , Tsuchida Chihiro , Kondo Keiichi 
Published: May 2012

AbstractFour sorts of epoxy resins containing degradable acetal linkages were synthesized by the reaction of bisphenol A (BA) or cresol novolak (CN) resin with vinyl ethers containing a glycidyl group [4‐vinlyoxybutyl glycidyl ether (VBGE) and cyclohexane dimethanol vinyl glycidyl ether (CHDMVG)] and cured with known typical amine‐curing agents. The thermal and mechanical properties of the cured resins were investigated. Among the four cured epoxy resins, the CN‐CHDMVG resin (derived from CN and CHDMVE) exhibited relatively high glass transition temperature (Tg = ca. 110 °C). The treatment of these cured epoxy resins with aqueous HCl in tetrahydrofuran (THF) at room temperature for 12 h generated BA and CN as degradation main products in high yield. Carbon fiber‐reinforced plastics (CFRPs) were prepared by heating the laminated prepreg sheets with BA‐CHDMVG (derived from BA and CHDMVE) and CN‐CHDMVG, in which strands of carbon fibers are impregnated with the epoxy resins containing conventional curing agents and curing accelerators. The obtained CFRPs showed good appearance and underwent smooth breakdown with the aqueous acid treatment in THF at room temperature for 24 h to produce strands of carbon fiber without damaging their surface conditions and tensile strength. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Synthesis and Photovoltaic Properties of Thieno[3,4‐c]pyrrole‐4,6‐dione‐based donor–acceptor Copolymers
Authors: Wen Shanpeng , Cheng Weidong , Li Pengfei , Yao Shiyu , Xu Bin , Li Hui , Gao Yajun , Wang Zilong , Tian Wenjing 
Published: May 2012

AbstractThree donor–acceptor (D–A) 1,3‐di(thien‐2‐yl)thieno [3,4‐c]pyrrole‐4,6‐dione‐based copolymers, poly{9,9‐dioctylfluorene‐2,7‐diyl‐alt‐1,3‐bis(4‐hexylthien‐2‐yl)‐5‐octylthieno[3,4‐c]pyrrole‐4,6‐dione}, poly{N‐(1‐octylnonyl)carbazole‐2,7‐diyl‐alt‐1,3‐bis(4‐hexylthien‐2‐yl)‐5‐octylthieno[3,4‐c]pyrrole‐4,6‐dione}, and poly {4,8‐bis(2‐ethylhexyloxyl) benzo[1,2‐b:3,4‐b′]dithiophene‐alt‐1,3‐bis(4‐hexylthien‐2‐yl)‐5‐octylthieno[3,4‐c] pyrrole‐4,6‐dione} were synthesized by Suzuki or Stille coupling reaction. By changing the donor segment, the bandgaps and energy levels of these copolymers could be finely tuned. Cyclic voltammetric study shows that the highest occupied molecular orbital (HOMO) energy levels of the three copolymers are deep‐lying, which implies that these copolymers have good stability in the air and the relatively low HOMO energy level assures a higher open‐circuit potential when they are used in photovoltaic cells. Bulk‐heterojunction photovoltaic cells were fabricated with these polymers as the donors and PC71BM as the acceptor. The cells based on the three copolymers exhibited power conversion efficiencies of 0.22, 0.74, and 3.11% with large open‐circuit potential of 1.01, 0.99, and 0.90 V under one sun of AM 1.5 solar simulator illumination (100 mW/cm2). © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Solvent‐free polymerization of citric acid and hexamethylenediamine for novel carboxylated polyamides
Authors: Jiang Man , Chen Wei , Fang Ping , Chen Shangli , Bai Junxiao , Huang Yanfei , Han Miaowei , Lu Ping , Dong Jian 
Published: May 2012

AbstractCopolymers of tributyl citrate (TBC) and hexamethylenediamine (HMDA) were synthesized with a solvent‐free condensation method with molar ratios of TBC to HMDA varying from 2:1 to 1:2. The reaction led to poly(succinimide‐co‐citramide) copolymers which were characterized by infrared and Raman spectroscopies, X‐ray diffraction, and thermal analyses. Hydrolysis of the copolymers resulted in water soluble polycitramides with number averaged molecular weights ranging from 1.16 × 104 to 5.00 × 103 as determined by gel permeation chromatography. 1H, 13C, and 13C‐1H‐heteronuclear single quantum coherence NMR spectroscopy has confirmed that the hydrolyzed polycitramides with COOH side chains and amide backbones are structurally similar to biodegradable poly(aspartic acid) (PASP). Interestingly, the polycitramides showed Ca2+ and Pb2+ ion chelating capabilities higher than PASP, citric acid–sorbitol copolymers, or conventional resins. Thus, the polycitramides offer promise as a totally new class of metal sequesters and renewable substitutes for PASP and poly(acrylic acid). © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Unoriented D‐brane instantons
Authors: Bianchi M. , Inverso G. 
Published: May 2012

AbstractWe give a pedagogical introduction to D‐brane instanton effects in vacuum configurations with open and unoriented strings. We focus on quiver gauge theories for unoriented D‐branes at orbifold singularities and describe in some detail the ℤ3 case, where both ‘gauge’ and ‘exotic’ instantons can generate non‐perturbative super potentials, and the ℤ5 case, where supersymmetry breaking may arise from the combined effect of ‘gauge’ instantons and a FI D‐term.
Computational methods for scaffold hopping
Authors: Schuffenhauer Ansgar 
Published: May 2012

AbstractIt is not uncommon in drug discovery that the core fragment, typically called scaffold, of a molecule with an interesting biological activity cannot be developed further because of issues related to intellectual property, physicochemical properties, metabolic stability, or toxicity, to name only a few reasons. In this situation, it is desirable to replace this molecule with another having a different chemical connectivity, but similar shape and pharmacophore features enabling it to interact in the same way with the target as the original molecule. Such a replacement is called scaffold hopping. Several ligand‐based virtual screening and scoring methods supporting the identification of novel ligands starting from known ligands and, if known, their bound conformation, are available. Scaffold hopping capability has been demonstrated for pharmacophore searches, field‐ and shape‐based similarity searches, alignment free similarity searches using three‐dimensional (3D)‐ or connectivity‐based descriptors, and fragment‐based methods. Although for many methods successful prospective uses have been reported, rigorous systematic benchmarking of scaffold hopping is still challenging due to the lacking consensus in the definition of a scaffold. Despite their drawbacks, computational scaffold extraction methods have been frequently used in approximate benchmarks for scaffold hopping. In many systematic retrospective studies, connectivity‐based methods were shown to be at least equally effective as 3D methods, especially when the conformations of the reference structures were generated with a conformer generator. However, in prospective comparison studies, especially when a hypothesis of the 3D binding conformation was available and used, often 3D methods were found to give superior results. © 2012 John Wiley & Sons, Ltd.This article is categorized under:

Computer and Information Science > Chemoinformatics
Synthesis, Crystal Structures, and Catalytic Properties of Silver(I) and Cobalt(II) Coordination Polymers Based on Flexible Bis(benzimidazole) with Pyridine‐2, 6‐Dicarboxylate
Authors: Geng Jian‐Chen , Qin Li , Du Xu , Xiao Shu‐Lin , Cui Guang‐Hua 
Published: May 2012

AbstractTwo coordination polymers, [Ag2(pydca)(bbbi)2]n (1) and [Co2(pydca)2(bbbi)3]n·nH2O (2) [pydca = pyridine‐2, 6‐dicarboxylate, bbbi = 1, 1′‐(1, 4‐butylene)bis‐1H‐benzimidazole)] were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, TG, PXRD, and single‐crystal X‐ray diffraction. Compound 1 features a one‐dimensional helical chain structure bridged by bbbi ligand, and further assembled into a 2D supramolecular architecture through three kinds of intermolecular π–π stacking interactions. Compound 2 displays an undulated 2D (6, 3) layer structure, in which each [Co(pydca)] unit is connected by three bbbi bridge ligands. Moreover, 1 and 2 have a remarkable activity for degradation of methyl orange in a photo‐assisted Fenton‐like process.
Systematic Investigation of Porous Inorganic‐Organic Hybrid Compounds with Photo‐Switchable Properties
Authors: Modrow Antje , Feyand Mark , Zargarani Dordaneh , Herges Rainer , Stock Norbert 
Published: May 2012

AbstractFour new compounds [Co2(NDC)2(AzBIPY)] (1), [Cu2(NDC)2(AzBIPY)] (2), [Zn2(BPDC)2(AzBIPY)] (3) and [Zn2(CCA)2(AzBIPY)] (4) (with H2NDC: 2, 6‐naphthalenedicarboxylic acid, AzBIPY: 3‐azo‐phenyl‐4, 4′‐bipyridine, H2BPDC: 4, 4′‐biphenyl‐dicarboxylic acid and H2CCA: 4‐carboxy‐cinnamic acid) were synthesized and characterized. All compounds have paddle‐wheel units and photo switchable linker molecules in common. In all four compounds the azo group of the AzBIPY linker molecule protrudes into the pores. For compound 1 and 2 isomerization can be accomplished upon irradiation with UV light (λ = 365 nm) to switch the thermodynamically stable trans‐isomer into the cis‐isomer. Back switching can be achieved thermally or by irradiation with visible light (λ = 455 nm).
Synthesis and Structural Characterization of ACu9Tt4 (A = Ca, Sr, Ba, Eu; Tt = Si, Ge, Sn) – Tetragonally Distorted Ternary Variants of the Cubic NaZn13 Structure Type. Improved Structure Refinement of SrCu2Ge2
Authors: Schäfer Marion C. , Yamasaki Yuki , Fritsch Veronika , Bobev Svilen 
Published: May 2012

AbstractInvestigations in the Cu‐rich parts of the ternary systems A–Cu–Tt (A = Ca, Sr, Ba, Eu, Yb; Tt = Si, Ge, Sn) were carried out using the molten flux method. The results indicate that using tin as a flux, several stannides with a general formula ACu9Sn4 (A = Ca, Sr, Ba, and Eu) can be readily synthesized. Their structures (space group I4/mcm, Pearson symbol tI56) are ordered ternary variants of the cubic NaZn13 structure type. In the corresponding germanium and silicon systems, only the solid solutions BaCu9–xGe4+x and BaCu9–xSi4+x (x ≈ 0.5) can be obtained from eutectic Cu:Tt mixtures with compositions approximately 2:1. Their structures are formally isotypic with the CeNi8.5Si4.5 structure type, a partially ordered variant of the same NaZn13 structure. In the remaining systems A–Cu–Tt (A = Ca, Sr, Eu, Yb; Tt = Si, Ge), the known ACu2Tt2 phases (space group I4/mmm, Pearson symbol tI10) with the ThCr2Si2 structure type were found to be the most frequently observed products. In this article we discuss the subtleties of each structure with regard to the synthetic route; the similarities and the differences in the syntheses, and the structure refinements among the studied compounds are compared and contrasted. The structure of SrCu2Ge2 was also re‐assessed.
N‐Methyl‐2, 2'‐Dipicolylamine Complexes as Potential Models for Metal‐Mediated Base Pairs
Authors: Seubert Kristof , Böhme Dominik , Kösters Jutta , Shen Wei‐Zheng , Freisinger Eva , Müller Jens 
Published: May 2012

AbstractMetal‐mediated base pairs can be used to insert metal ions into nucleic acids at precisely defined positions. As structural data on the resulting metal‐modified DNA are scarce, appropriate model complexes need to be synthesized and structurally characterized. Accordingly, the molecular structures of nine transition metal complexes of N‐methyl‐2, 2'‐dipicolylamine (dipic) are reported. In combination with an azole‐containing artificial nucleoside, this tridentate ligand had recently been used to generate metal‐mediated base pairs (Chem. Commun. 2011, 47, 11041–11043). The PdII and PtII complexes reported here confirm that the formation of planar complexes (as required for a metal‐mediated base pair) comprising N‐methyl‐2, 2'‐dipicolylamine is possible. Two HgII complexes with differing stoichiometry indicate that a planar structure might also be formed with this metal ion, even though it is not favored. In the complex [Ag2(dipic)2](ClO4)2, the two AgI ions are located close to one another with an Ag···Ag distance of 2.9152(3) Å, suggesting the presence of a strong argentophilic interaction.
Constraints on the pMSSM from searches for squarks and gluinos by ATLAS
Authors: Strübig Antonia , Caron Sascha , Rammensee Michael 
Published: May 2012

Abstract

We study the impact of the jets and missing transverse momentum SUSY anal- yses of the ATLAS experiment on the phenomenological MSSM (pMSSM). We investigate sets of SUSY models with a flat and logarithmic prior in the SUSY mass scale and a mass range up to 1 and 3 TeV, respectively. These models were found previously in the study ’Supersymmetry without Prejudice’. Removing models with long-lived SUSY particles, we show that 99 % of 20000 randomly generated pMSSM model points with a flat prior and 85 % for a logarithmic prior are excluded by the ATLAS results. For models with squarks and gluinos below 600 GeV all models of the pMSSM grid are excluded. We identify SUSY spectra where the current ATLAS search strategy is less sensitive and propose extensions to the inclusive jets search channel.