bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cyano‐Functionalized Triarylamines on Coinage Metal Surfaces: Interplay of Intermolecular and Molecule–Substrate Interactions
Authors: Müller Kathrin , Moreno‐López Juan Carlos , Gottardi Stefano , Meinhardt Ute , Yildirim Handan , Kara Abdelkader , Kivala Milan , Stöhr Meike 
Published: December 2015

AbstractThe self‐assembly of cyano‐functionalized triarylamine derivatives on Cu(111), Ag(111) and Au(111) was studied by means of scanning tunnelling microscopy, low‐energy electron diffraction, X‐ray photoelectron spectroscopy and density functional theory calculations. Different bonding motifs, such as antiparallel dipolar coupling, hydrogen bonding and metal coordination, were observed. Whereas on Ag(111) only one hexagonally close‐packed pattern stabilized by hydrogen bonding is observed, on Au(111) two different partially porous phases are present at submonolayer coverage, stabilized by dipolar coupling, hydrogen bonding and metal coordination. In contrast to the self‐assembly on Ag(111) and Au(111), for which large islands are formed, on Cu(111), only small patches of hexagonally close‐packed networks stabilized by metal coordination and areas of disordered molecules are found. The significant variety in the molecular self‐assembly of the cyano‐functionalized triarylamine derivatives on these coinage metal surfaces is explained by differences in molecular mobility and the subtle interplay between intermolecular and molecule–substrate interactions.
Shape‐Memory Platinum(II) Complexes: Intelligent Vapor‐History Sensor with ON–OFF Switching Function
Authors: Shigeta Yasuhiro , Kobayashi Atsushi , Ohba Tadashi , Yoshida Masaki , Matsumoto Takeshi , Chang Ho‐Chol , Kato Masako 
Published: December 2015

AbstractA novel platinum(II)–diimine complex, [Pt(CN)2(H2dcphen)] (1; H2dcphen=4,7‐dicarboxy‐1,10‐ phenanthroline), was synthesized and its vapochromic shape‐memory behavior was evaluated. The as‐synthesized amorphous purple solid, [Pt(CN)2(H2dcphen)]⋅2 H2O (1 P), exhibited vapochromic behavior in the presence of alcoholic vapors through transformation to a red, crystalline, porous, vapor‐adsorbed form, 1 R⊃vapor. The obtained 1 R⊃vapor complex released the adsorbed vapors upon heating without collapse of the porous structure. The vaporfree, porous 1 R⊃open could detect water or n‐hexane vapor, although these vapors could not induce 1 P‐to‐1 R⊃vapor transformation, and 1 R⊃open could easily be converted to the initial 1 P by manual grinding. These results indicate that 1 is a new shape‐memory material that functions through formation and collapse of the porous framework with an emission change upon vapor‐adsorption and grinding; this enables it to exhibit vapor history and ON–OFF switching sensing functions.
Expanding the Chemistry of Molecular U2+ Complexes: Synthesis, Characterization, and Reactivity of the {[C5H3(SiMe3)2]3U}− Anion
Authors: Windorff Cory J. , MacDonald Matthew R. , Meihaus Katie R. , Ziller Joseph W. , Long Jeffrey R. , Evans William J. 
Published: December 2015

AbstractThe synthesis of new molecular complexes of U2+ has been pursued to make comparisons in structure, physical properties, and reactivity with the first U2+ complex, [K(2.2.2‐cryptand)][Cp′3U], 1 (Cp′=C5H4SiMe3). Reduction of Cp′′3U [Cp′′=C5H3(SiMe3)2] with KC8 in the presence of 2.2.2‐cryptand or 18‐crown‐6 generates [K(2.2.2‐cryptand)][Cp′′3U], 2‐K(crypt), or [K(18‐crown‐6)(THF)2][Cp′′3U], 2‐K(18c6), respectively. The UV/Vis spectra of 2‐K and 1 are similar, and they are much more intense than those of U3+ analogues. Variable temperature magnetic susceptibility data for 1 and 2‐K(crypt) reveal lower room temperature χMT values relative to the experimental values for the 5f3 U3+ precursors. Stability studies monitored by UV/Vis spectroscopy show that 2‐K(crypt) and 2‐K(18c6) have t1/2 values of 20 and 15 h at room temperature, respectively, vs. 1.5 h for 1. Complex 2‐K(18c6) reacts with H2 or PhSiH3 to form the uranium hydride, [K(18‐crown‐6)(THF)2][Cp′′3UH], 3. Complexes 1 and 2‐K(18c6) both reduce cyclooctatetraene to form uranocene, (C8H8)2U, as well as the U3+ byproducts [K(2.2.2‐cryptand)][Cp′4U], 4, and Cp′′3U, respectively.
Photoswitchable “Turn‐on” Fluorescence Diarylethenes: Substituent Effects on Photochemical Properties and Electrochromism
Authors: Ai Qi , Pang Shichong , Ahn Kwang‐Hyun 
Published: December 2015

AbstractA series of “turn‐on” fluorescence diarylethenes derived from 2,3‐bis(2‐methylbenzo[b]thiophen‐3‐yl)‐5,6‐dihydro‐4H‐thieno[2,3‐b]thiopyran‐4‐one (1) with alkyl and acetyl substituents were synthesized. The photochemical and photophysical properties of these derivatives, including the photoreaction of crystalline 1, were thoroughly investigated to reveal substituent effects on their properties. The results indicated that alkyl substituents did not significantly affect the absorption and emission spectra of the diarylethenes. However, large absorption and emission wavelength shifts were observed for the diarylethene with an acetyl substituent due to extension of π–π conjugation. Significantly, all of the fluorescent ring‐closed forms of the compounds isomerized to their ring‐open forms in the presence of Cu2+ in the dark. EPR results provide clear evidence for the formation of the compound 1 radical cation intermediate that might be generated in the reaction between c‐1 and Cu2+. DFT calculations found that the ground‐state activation energy for ring‐opening of 1.+ was approximately 9.2 kcal mol−1 lower than that of 1 without Cu2+, such that a Cu2+‐catalyzed oxidative cycloreversion reaction at room temperature might be possible.
Triphenylphosphine‐Mediated Deoxygenative Reduction of CF3SO2Na and Its Application for Trifluoromethylthiolation of Aryl Iodides
Authors: Yang Yi , Xu Long , Yu Siqi , Liu Xiaoqiang , Zhang Yu , Vicic David A. 
Published: December 2015

AbstractWe report herein a practical method for taming Langlois’ reagent CF3SO2Na to generate CuSCF3 by a triphenylphospine‐mediated deoxygenative reduction process. This chemistry highlights a novel utilization of the inherent CF3S skeleton of Langlois’ reagent as a CF3S feedstock under mild conditions. The CuSCF3 intermediate generated by this protocol can react with a wide array of supporting ligands to furnish several air‐stable [LCu(SCF3)] complexes as valuable trifluoromethylthiolating agents. In addition, the CuSCF3 intermediate can be directly employed for the trifluoromethylthiolation of (hetero)aryl iodides with operational simplicity and atomic efficiency.
Pyrimidine Triazole Thioether Derivatives as Toll‐Like Receptor 5 (TLR5)/Flagellin Complex Inhibitors
Authors: Yan Lei , Liang Jiaqi , Yao Chengbo , Wu Peiyao , Zeng Xianfeng , Cheng Kui , Yin Hang 
Published: December 2015

AbstractProtein–protein interactions have been regarded as “undruggable” despite their importance in many biological processes. The complex formed between host toll‐like receptor 5 (TLR5) and flagellin, a globular protein that is the main component of a bacterial flagellum, plays a vital role in a number of pathogen defenses, immunological diseases and cancers. Through high‐throughput screening, we identified two hits with a common pharmacophore, which were used to successfully develop a series of small‐molecule probes as novel inhibitors of flagellin binding to TLR5. In a multitude of assays, 4‐((4‐benzyl‐5‐(pyridin4yl)‐4H‐1,2,4‐triazol‐3‐yl)thio)pyrido[3′,2′:4,5]thieno[3,2‐d]pyrimidine (TH1020) was identified as a potent antagonist of TLR5 signaling with promising activity (IC50=0.85±0.12 μm) and specificity. Furthermore, TH1020 was shown to repress the expression of downstream TNF‐α signaling pathways mediated by the TLR5/flagellin complex formation. Based on molecular docking simulation, TH1020 is suggested to compete with flagellin and disrupt its association with TLR5. TH1020 provides a much‐needed molecular probe for studying this important protein–protein interaction and a lead compound for identifying novel therapeutics targeting TLR5.
Spectrum of epidemiological and clinical findings in patients with heart failure with preserved ejection fraction stratified by study design: a systematic review
Authors: Vaduganathan Muthiah , Michel Alexander , Hall Kathryn , Mulligan Claire , Nodari Savina , Shah Sanjiv J. , Senni Michele , Triggiani Marco , Butler Javed , Gheorghiade Mihai 
Published: December 2015

BackgroundHeart failure with preserved ejection fraction (HFpEF) represents a major global and economic burden, but its epidemiological, clinical, and outcome data have varied according to study design.Methods and resultsWe conducted a systematic review of published HFpEF clinical trials and observational studies (community‐based studies and registries) from August 1998 to July 2013 using PubMed and EMBASE databases. Two independent investigators manually screened and extracted relevant data. We included 62 articles (19 describing clinical trials, 12 describing community‐based observational studies, and 31 describing registries). The ejection fraction (EF) cut‐off values ranged widely for HFpEF from >40% to >55%. However, differences in EF cut‐offs were not clearly associated with incidence and prevalence data across studies. Of all patients with heart failure in community studies, 33–84% had HFpEF, which tended to be higher than reported in registries. The HFpEF patients in included studies were primarily older, white (>70%) patients with hypertension (∼50–90%) and coronary artery disease (up to 60%). All‐cause mortality and all‐cause hospitalizations ranged from 13% to 23% (26–50 months follow‐up) and 55% to 67% (37–50 months follow‐up), respectively, in clinical trials; cardiovascular causes accounted for 70% of both outcomes. All‐cause mortality tended to be higher in registries than in clinical trials and community‐based observational studies up to 5 years into follow‐up.ConclusionsImportant differences in EF thresholds, epidemiological indices, clinical profiles, treatment patterns, and outcomes exist across contemporary HFpEF clinical trials, observational studies, and registries. Precision in definition and inclusion of more uniform populations may facilitate improved profiling of HFpEF patients.
Examining the Relationships Between Bone Tissue Composition, Compositional Heterogeneity, and Fragility Fracture: A Matched Case-Controlled FTIRI Study
Authors: Boskey Adele L , Donnelly Eve , Boskey Elizabeth , Spevak Lyudmila , Ma Yan , Zhang Wei , Lappe Joan , Recker Robert R 
Published: December 2015

ABSTRACT

Fourier transform infrared imaging (FTIRI) provides information on spatial distribution of the chemical composition of thin tissue specimens at ∼7 µm spatial resolution. This study of 120 age- and bone mineral density (BMD)-matched patients was designed to investigate the association of FTIRI variables, measured in iliac crest biopsies, with fragility fractures at any site. An earlier study of 54 women found hip BMD to be a significant explanatory variable of fracture risk for cortical bone but not for cancellous bone. In the current study, where age and BMD were controlled through matching, no such association was observed, validating the pairing scheme. Our first study of unmatched iliac crest biopsies found increases in collagen maturity (cancellous and cortical bone) and mineral crystal size (cortical bone only) to be a significant explanatory variable of fracture when combined with other covariates. The ratio for collagen maturity has been correlated to the amount of enzymatic collagen cross-links. To assess the impact of other FTIRI variables (acid phosphate substitution, carbonate-to-phosphate ratio, and the pixel distribution [heterogeneity] of all relevant FTIRI variables), we examined biopsies from a matched case-controlled study, in which 60 women with fractures were each paired with an age- and BMD-matched female control. With the matched data set of 120 women, conditional logistic regression analyses revealed that significant explanatory variables of fracture were decreased carbonate-to-phosphate ratio in both cancellous (odds ratio [OR] = 0.580, 95% confidence interval [CI] 0.37–0.909, p = 0.0176) and cortical bone (OR = 0.519, 95% CI 0.325–0.829, p = 0.0061), and increased heterogeneity (broadened pixel distribution) of collagen maturity for cancellous bone (OR = 1.549, 95% CI 1.002–2.396, p = 0.0491). The observation that collagen maturity was no longer linked to fracture in age- and BMD-matched samples suggests that age-dependent variation in collagen maturity may be a more important contributory factor to fragility fractures than previously thought. © 2015 American Society for Bone and Mineral Research.
Mitigating the Effects of Nonadherence in Clinical Trials
Authors: Shiovitz Thomas M. , Bain Earle E. , McCann David J. , Skolnick Phil , Laughren Thomas , Hanina Adam , Burch Daniel 
Published: December 2015

AbstractAccounting for subject nonadherence and eliminating inappropriate subjects in clinical trials are critical elements of a successful study. Nonadherence can increase variance, lower study power, and reduce the magnitude of treatment effects. Inappropriate subjects (including those who do not have the illness under study, fail to report exclusionary conditions, falsely report medication adherence, or participate in concurrent trials) confound safety and efficacy signals. This paper, a product of the International Society for CNS Clinical Trial Methodology (ISCTM) Working Group on Nonadherence in Clinical Trials, explores and models nonadherence in clinical trials and puts forth specific recommendations to identify and mitigate its negative effects. These include statistical analyses of nonadherence data, novel protocol design, and the use of biomarkers, subject registries, and/or medication adherence technologies.
Light‐Controlled Radical Polymerization of Functional Methacrylates Prepared by Enzymatic Transacylation
Authors: Mommer Stefan , Köhler Jens , Keul Helmut , Möller Martin 
Published: December 2015

Well‐defined homo and block copolymers are prepared with methyl methacrylate, pentyl methacrylate, 3‐phenylpropyl methacrylate, and 6‐thiobenzoylhexyl methacrylate using Ir(ppy)3 as a catalyst. It is shown that the advantages of the light‐controlled radical polymerization can be exploited also for these special monomers as prepared by enzymatic transacylation without time‐consuming labor‐intensive removal of side products. Furthermore, it is shown that the polymerization is significantly affected even by small variations in the irradiation and therefore also by choice of the light source. In contrast to our recent report we therefore recommend removal of the heterogeneous supported enzyme by filtration before polymerization. Because of the sensitivity of the polymerization process to the irradiation, turbidity caused by the bead‐supported enzyme can affect the reproducibility of the polymer preparation. Results obtained with methyl methacrylate as monomer could only be transferred to the above‐mentioned functional monomers by proper choice of the light source. On the basis of kinetic investigations, the effect of the irradiation source, the catalyst concentration, and the alcohol residue on the methacrylate used are discussed. Finally, the optimized experimental conditions are applied for the preparation of different block copolymers.
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Microstructure and property of Ni60A/WC composite coating fabricated by fiber laser cladding
Authors: Wang K.‐M. , Fu H.‐G. , Lei Y.‐P. , Yang Y.‐W. , Li Q.‐T. , Su Z.‐Q. 
Published: December 2015

Laser clad Ni60A/WC composite coating was fabricated on the surface of Q235 steel by using 6 kW fiber laser. The morphology, composition, and microhardness of composite coating were studied by using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X‐ray diffraction (XRD), and micro‐hardness tester. The results show that in the process of fiber laser cladding Ni60A/WC composite coating, residual WC particles partially dissolve and react with other elements to form eutectics, which exists in the shape of lumpy, strip and spherical. The main structures of laser cladding are γ‐Ni, WC, W2C, M7C3, M23C6 etc. From the hardness analysis, the average hardness of the composite coating is four times of the substrate.
Nonlinear optical responses in hydrogenated graphene structures
Authors: Zapata‐Peña Reinaldo , Anderson Sean M. , Mendoza Bernardo S. , Shkrebtii Anatoli I. 
Published: December 2015

AbstractAbstractauthoren We present a theoretical study of the optical spin injection, optical current injection, and second harmonic generation of two 50% hydrogenated graphene structures: CH‐alt and CH‐up. Optical spin injection, under the incidence of circularly polarized light onto nonmagnetic semiconductors, creates spin‐polarized electrons in the conduction bands. Optical current injection and second‐harmonic generation are nonlinear second‐order effects that are allowed in materials without inversion symmetry. The results are calculated in a full electronic band structure scheme within DFT in the LDA approximation. Our results show an anisotropic behavior in the optical responses of the spin, the current injection, and second harmonic generation. We obtained maximum absolute magnitudes of the degree of spin polarization of 61 and 64% for thealtandupstructures, respectively, and it is also possible to optically generate an injection current coming mainly from the carbon layer on bothaltandupsystems. Besides, we found that both structures are excellent candidates for second harmonic generation.
Design and implementation of a block‐backstepping based tracking control for nonholonomic wheeled mobile robot
Authors: Rudra Shubhobrata , Barai Ranjit Kumar , Maitra Madhubanti 
Published: December 2015

SummaryThis paper presents formulation of a novel block‐backstepping based control algorithm to overcome the challenges posed by the tracking and the stabilization problem for a differential drive wheeled mobile robot (WMR). At first, a two‐dimensional output vector for the WMR has been defined in such a manner that it would decouple the two control inputs and, thereby, allow the designer to formulate the control laws for the two inputs one at a time. Actually, the decoupling has been carried out in a way to convert the system into block‐strict feedback form. Thereafter, block‐backstepping control algorithm has been utilized to derive the expressions of the control inputs for the WMR system. The proposed block‐backstepping technique has further been enriched by incorporating an integral action for enhancing the steady state performance of the overall system. Global asymptotic stability of the overall system has been analyzed using Lyapunov stability criteria. Finally, the proposed control algorithm has been implemented on a laboratory scale differential drive WMR to verify the effectiveness of the proposed control law in real‐time environment. Indeed, the proposed design approach is novel in the sense that it has judiciously exploited the nonholonomic constraint of the WMR to result in a reduced order block‐backstepping controller for the WMR, and thereby, it has eventually yielded a compact expression of the control law that is amenable to real‐time implementation. Copyright © 2015 John Wiley & Sons, Ltd.
Stochastic consensus control with finite frequency specification for Markov jump networks
Authors: Luan Xiaoli , Zhou Chaojie , Ding Zhengtao , Liu Fei 
Published: December 2015

SummaryA stochastic finite frequency consensus protocol for directed networks with Markov jump topologies and external disturbances is proposed in this paper. By introducing the frequency band information into consensus control design, the disagreement dynamics of interconnected networks asymptotically converge to zero with an improved level of disturbance attenuation in the specific frequency band. In addition, the new model transformation approach is presented by exploring certain features of Laplacian matrix in real Jordan form, which leads to more generality of the designed protocol. A numerical example validates the potential of the developed results. Copyright © 2015 John Wiley & Sons, Ltd.
Widening with thresholds via binary search
Authors: Kim Sol , Heo Kihong , Oh Hakjoo , Yi Kwangkeun 
Published: December 2015

SummaryIn this paper, we present a useful technique for implementing practical static program analyzers that use widening. Our technique aims to improve the efficiency of the conventional widening‐with‐thresholds technique at a small precision compromise. In static analysis, widening is used to accelerate (or converge) fixed point iterations. Unfortunately, this acceleration often comes with a significant loss in analysis precision. A standard method to improve the precision is to apply the widening with a set of thresholds. However, this technique may significantly slow down the analysis, because in practice it is commonplace to use a large set of thresholds. In worst case, the technique increases the analysis cost by the sizeNof the threshold set. In this paper, we propose a technique to reduce the worst case by, by employing a binary search in the process of applying threshold values. We formalize the technique in the abstract interpretation framework and show that, by experiments with a realistic static analyzer for C, our technique considerably improves the efficiency (by 81.5%) of the existing method with a small compromise (20.9%) on the analysis precision. Copyright © 2015 John Wiley & Sons, Ltd.
Wind‐induced inter‐story drift analysis and equivalent static wind load for multiple targets of tall buildings
Authors: Fu J. Y. , Zheng Q. X. , Wu J. R. , Huang Y. Q. 
Published: December 2015

SummaryIn super high‐rise buildings with varying story heights, the wind‐induced inter‐story drifts might violate the specified limit. However, these effects have seldom been concerned in wind‐induced response analysis. The theory and application of equivalent static wind load (ESWL) for wind‐induced inter‐story drifts of super high‐rise buildings were studied in this paper. A spectral decomposition method suitable for multi‐point excitation problems was firstly proposed. The formula of ESWL targeting for largest inter‐story drift was derived. For more reasonable structural design, the ESWL for multiple targets including displacement atop of building and inter‐story drifts at all story levels is put forward, in which the dominant modal inertial forces are adopted as the based load vectors. The presented methods were finally verified by its application for the wind‐induced response analysis for a tallest super tall building in Guangzhou. The researched results showed that the proposed spectral decomposition method not only has the same precision as the complete quadratic combination method but also possesses higher computation efficiency. The ESWL for multiple targets produces the same static responses for all the specified wind‐induced response, so it is much more rational for wind‐resistant structural design. Meanwhile, it is more reasonable to select the wind‐induced responses in the same direction simultaneously as the targeted values for obtaining the required ESWLs; however, the ESWL targeting for the wind‐induced responses in all degrees of freedom would generate more queer and unrealistic ESWLs distribution. Copyright © 2015 John Wiley & Sons, Ltd.