bluuebunny/crossref_metadata_2025 huggingface dataset:
Bioorthogonal Probes for Imaging Sterols in Cells
Authors: Jao Cindy Y. , Nedelcu Daniel , Lopez Lyle V. , Samarakoon Thilani N. , Welti Ruth , Salic Adrian
Published: February 2015

Cholesterol is a fundamental lipid component of eukaryotic membranes and a precursor of potent signaling molecules, such as oxysterols and steroid hormones. Cholesterol and oxysterols are also essential for Hedgehog signaling, a pathway critical in embryogenesis and cancer. Despite their importance, the use of imaging sterols in cells is currently very limited. We introduce a robust and versatile method for sterol microscopy based on C19 alkyne cholesterol and oxysterol analogues. These sterol analogues are fully functional; they rescue growth of cholesterol auxotrophic cells and faithfully recapitulate the multiple roles that sterols play in Hedgehog signal transduction. Alkyne sterol analogues incorporate efficiently into cellular membranes and can be imaged with high resolution after copper(I)‐catalyzed azide–alkyne cycloaddition reaction with fluorescent azides. We demonstrate the use of alkyne sterol probes for visualizing the subcellular distribution of cholesterol and for two‐color imaging of sterols and choline phospholipids. Our imaging strategy should be broadly applicable to studying the role of sterols in normal physiology and disease.
Hydrophobic Mesoporous Poly(ionic liquid)s towards Highly Efficient and Contamination‐Resistant Solid‐Base Catalysts
Authors: Wang Xiaochen , Li Jing , Chen Guojian , Guo Zengjing , Zhou Yu , Wang Jun
Published: February 2015

Mesoporous poly(ionic liquid)s were synthesized by radical copolymerization of the ionic liquid 1‐aminoethyl‐3‐vinylimidazolium bromide with divinylbenzene plus the ion exchange of bromide anions with hydroxyls. Characterizations revealed the high ionic liquid content, large surface area, and hydrophobicity for the sample prepared with equimolar amounts of ionic liquid and divinylbenzene, with good accessibility to organic compounds and resistance to CO2/H2O contamination. The mesoporous copolymer behaved as a superior and recyclable solid‐base catalyst for solvent‐free Knoevenagel condensation of benzaldehyde with ethyl cyanoacetate, giving the much higher turnover frequency of 304 h−1 (yield 99 %, 0.5 h) than those of the nonporous analogues, commercial strong basic resins, and even homogeneous NaOH. The high activity was confirmed by Knoevenagel condensation with various substrates and Claisen–Schmidt condensation. A possible synergistic Lewis–Brønsted dual‐base‐center mechanism is proposed for understanding the catalytic behavior.
Synthesis, Crystal Structure, and Colloidal Dispersions of Vanadium Tetrasulfide (VS4)
Authors: Kozlova Mariia N. , Mironov Yuri V. , Grayfer Ekaterina D. , Smolentsev Anton I. , Zaikovskii Vladimir I. , Nebogatikova Nadezhda A. , Podlipskaya Tatyana Yu. , Fedorov Vladimir E.
Published: February 2015

Although many of the layered metal chalcogenides, such as MoS2, are well‐studied, some other chalcogenides have received less attention by comparison. In particular, there has been an emerging interest in vanadium tetrasulfide (VS4), which displays useful properties as a component of hybrids. However, the synthetic methods and characteristics of individual VS4 are not yet well defined, and there is no report on its solution processability. Here we have synthesized VS4 by a simple and fast direct reaction between elements. Reinvestigation of the VS4 crystal structure yielded more precise atomic coordinates and interatomic distances, thereby confirming the crystallization of VS4 in the monoclinic C2/c group and its quasi‐1D chainlike structure. As the chains in VS4 are only bonded by weak van der Waals forces, we further demonstrate that bulk VS4 may be ultrasonically dispersed in appropriate solvents to form colloids, similarly to the layered chalcogenides. VS4 particles in colloids retain their phase identity and rod‐shaped morphology with lengths in the range of hundreds of nanometers. Isopropanol dispersion exhibited the highest concentration and stability, which was achieved owing to the repulsion caused by high negative charges on the edges of the particles.
Hydrogen Production on a Hybrid Photocatalytic System Composed of Ultrathin CdS Nanosheets and a Molecular Nickel Complex
Authors: Xu You , Yin Xuguang , Huang Yi , Du Pingwu , Zhang Bin
Published: February 2015

The production of clean and renewable hydrogen through water splitting by using solar energy has received much attention due to the increasing global energy demand. We report an economic and artificial photosynthetic system free of noble metals, consisting of ultrathin CdS nanosheets as a photosensitizer and nickel‐based complex as a molecular catalyst. Emission quenching and flash photolysis studies reveal that this hybrid system allows for effective electron transfer from the excited CdS nanosheets to the nickel‐based complex to generate reduced intermediate species for efficient hydrogen evolution. Notably, the unique morphological and structural features of the ultrathin CdS nanosheets contribute to the highly efficient photocatalytic performance. As a consequence, the resulting system shows exceptional activity and stability for photocatalytic hydrogen evolution in aqueous solution with a turnover number (TON) of about 28 000 versus catalyst and a lifetime of over 90 h under visible light irradiation.
Catalytic Asymmetric Crotylation of Aldehydes: Application in Total Synthesis of (−)‐Elisabethadione
Authors: O'Hora Paul S. , Incerti‐Pradillos Celia A. , Kabeshov Mikhail A. , Shipilovskikh Sergei A. , Rubtsov Aleksandr E. , Elsegood Mark R. J. , Malkov Andrei V.
Published: February 2015

A new, highly efficient Lewis base catalyst for a practical enantio‐ and diastereoselective crotylation of unsaturated aldehydes with E‐ and Z‐crotyltrichlorosilanes has been developed. The method was employed as a key step in a novel asymmetric synthesis of bioactive serrulatane diterpene (−)‐elisabethadione. Other strategic reactions for setting up the stereogenic centers included anionic oxy‐Cope rearrangement and cationic cyclization. The synthetic route relies on simple, high yielding reactions and avoids use of protecting groups or chiral auxiliaries.
A Potent Anticancer Agent of Shikonin Derivative Targeting Tubulin
Authors: Baloch Shahla Karim , Ma Lin , Xu Guo‐Hua , Bai Li‐Fei , Zhao Hua , Tang Cheng‐Yi , Pang Yan‐Jun , Yang Rong‐Wu , Wang Xiao‐Ming , Lu Gui‐Hua , Yang Yong‐Hua
Published: February 2015

In this study, a shikonin ester derivative, compound 3g, was selected to evaluate its anticancer activities and we found that compound 3g exhibited better antitubulin activities against the human HepG2 cell line with an IC50 value of 1.097 μM. Furthermore, the inhibition of tubulin polymerization results indicated that compound 3g demonstrated the most potent antitubulin activity (IC50 = 13.88), which was compared with shikonin and colchicine as positive controls (IC50 = 25.28 μM and 22.56 μM), respectively. Compound 3g was simulated to have good binding site with tubulin and arrested the cell cycle at G2/M phase, which also induces apoptosis in HepG2 cells, in which P53 and members of Bcl‐2 protein family were both involved in the progress of apoptosis revealed by western blot. Confocal microscopy observations revealed compound 3g targeted tubulin and altered its polymerization by interfering with microtubule organization. Based on these results, compound 3g functions as a potent anticancer agent targeting tubulin. Chirality 27:274–280, 2015.. © 2015 Wiley Periodicals, Inc.
Rational macromodeling of 1D blood flow in the human cardiovascular system
Authors: Ferranti Francesco , Tamburrelli Vincenzopio , Antonini Giulio
Published: February 2015

In this paper, we present a novel rational macromodeling approach for the description of 1D blood flow in the human cardiovascular system, which is suitable for time‐domain simulations. Using the analogy of the blood flow propagation problem with transmission lines and considering the hypothesis of linearized Navier–Stokes equations, a frequency‐domain rational macromodel for each arterial segment has been built. The poles and the residues of each arterial segment macromodel have been calculated by means of the Vector Fitting technique. Finally, the rational macromodel of the whole cardiovascular system is obtained by properly combining the macromodels of the single arterial segments using an interconnect matrix. The rational form of the proposed cardiovascular model leads to a state‐space or electrical circuit model suitable for time‐domain analysis. The stability and passivity properties of the global cardiovascular model are discussed to guarantee stable time‐domain simulations. The proposed macromodeling approach has been validated by pertinent numerical results. Copyright © 2015 John Wiley & Sons, Ltd.
Synergistic Effects and Correlating Polarity Parameters in Binary Mixtures of Ionic Liquids
Authors: Beniwal Vijay , Kumar Anil
Published: February 2015

Understanding how a chemical reaction proceeds in solution requires precise knowledge of solute–solvent interactions. Certain issues involved in ionic liquid binary mixtures are still not clearly understood, including: 1) the effects of hydrogen‐bond‐acceptor basicity (β) of solvents on the “synergistic effects” found in ionic liquid–alcohol mixtures, 2) the interrelation between the polarity parameters in binary mixtures, and 3) the application of a model for the description of normalised electronic transition energy for all the binary mixtures. Here, a detailed analysis of polarity parameters in both hydrophilic and hydrophobic ionic liquids has been carried out. A three‐parameter model developed by Roses et al. [J. Chem. Soc. Perkin Trans. 2­ 1997, 1341—1348] was found to be applicable to all the binary mixtures, and synergistic effects are generated as a result of high β values of alcohols compared with those of the ionic liquids. A strong correlation was observed in the β values and hydrophobicities of pure ionic liquids, suggesting that β values can play a role in describing synergism.
New Potentiometric Sensors Based on Ionic Associates of Sodium Dodecylsulfate and Cationic Complexes of Copper(II) with some Organic Reagents
Authors: Makarova N. M. , Kulapina E. G.
Published: February 2015

New potentiometric sensors with polymeric plasticized membranes based on ionic associates of sodium dodecylsulfate (DDS) and cationic complexes of copper(II) with some organic reagents (1,10‐phenanthroline (Phen), N,N′‐bis(salicylidene)ethylenediamine (Salen), α,α′‐dipyridyl (Dipyr) were developed for quantitative determination of homologous sodium alkylsulfates in a wide concentration range 2.0×10−7 (5.0×10−7)–1.0×10−2 (5.0×10−4) M. The low detection limit of DDS was 1.0×10−7 M (28.8 μg/L). The electrodes demonstrated good and extremely stable response to sodium alkylsulfates and were successfully applied to determination of anionic surfactants in water solutions, technical raw preparations, detergents, cosmetic and cleaners.
Improving the Upper Detection Limit of Potentiometric Sensors
Authors: Woźnica Emilia , Wójcik Michał M. , Wojciechowski Marcin , Mieczkowski Józef , Bulska Ewa , Maksymiuk Krzysztof , Michalska Agata
Published: February 2015

In this work the problem of upper detection limit of potentiometric sensors is addressed. Due to deviation of potentiometric plots from cationic Nernstian responses determination of analytes like silver cations in concentrations above 10−2 M is hardly possible, especially in the presence of background electrolyte containing lipophilic anions. Herein proposed approach applied classical complexing ligand, dithizone, attached to gold nanoparticles as ionophore. Immobilization on gold nanoparticles surface effectively anchores ligand molecules within the membrane phase. Thus obtained sensors are characterized with stable, Nernstian, potentiometric responses and selectivity comparable with classical membrane compositions. Moreover, due to lower formation constant of Ag+ with dithizone based ligand, herein reported sensors offer linear, Nernstian responses also in the range of high activity of AgNO3 solutions.
Microstructural, Impedance Spectroscopic and Potentiometric Analysis of Ta2O5 Electrochemical Thick Film pH Sensors
Authors: Manjakkal Libu , Cvejin Katarina , Bajac Branimir , Kulawik Jan , Zaraska Krzysztof , Szwagierczak Dorota
Published: February 2015

Two types of pH sensors based on Ta2O5 thick films, interdigitated conductimetric and potentiometric ones, were screen printed on an alumina substrate. Their properties were characterized by X‐ray diffraction, Raman spectroscopy, scanning electron microscopy, energy dispersive X‐ray spectroscopy, electrochemical impedance spectroscopy and potentiometry. The impedance spectroscopic studies of the fabricated thick film sensors were carried out in the frequency range of 10 Hz–2 MHz in test solutions of pH 3–12. The conductance, capacitance and impedance of the fabricated conductimetric Ta2O5 sensor were found to be distinctly pH‐dependent at low frequencies. For potentiometric sensors, a sub‐Nernstian behavior was obtained.
Potential Cycling Stability of Composite Films of Graphene Derivatives and Poly(3,4‐ethylenedioxythiophene)
Authors: Lindfors Tom
Published: February 2015

The potential cycling stability is compared for poly(3,4‐ethylenedioxythiophene) (PEDOT) composite films prepared either with graphene oxide (GO), reduced GO (RGO) or poly(styrenesulfonate) (PSS). It is shown that PEDOT‐GO had reversible redox behavior and fast charging/discharging with at least equal electrochemical properties to PEDOT‐PSS. 10 000 potential cycles between −0.5–0.5 V in the three‐electrode cell decreased the anodic charge of PEDOT‐GO with 6.2 %. In the two‐electrode cell, the decrease was only 5.4 % between 0–0.7 V. The potential cycling stability of PEDOT‐GO and PEDOT‐RGO prepared electrochemically without other additives than GO has not been previously reported.
Development of Lab‐to‐Fab Production Equipment Across Several Length Scales for Printed Energy Technologies, Including Solar Cells
Authors: Hösel Markus , Dam Henrik F. , Krebs Frederik C.
Published: February 2015

We describe and review how the scaling of printed energy technologies not only requires scaling of the input materials but also the machinery used in the processes. The general consensus that ultrafast processing of technologies with large energy capacity can only be realized using roll‐to‐roll methods is taken as a premise, and thus the progression from a highly successful laboratory technique (i.e., spin coating) to large‐scale roll‐to‐roll equipment is described in terms of all of the intermediate steps that must be available to make the transfer possible. Spin coating is compatible with materials availability on the small scale and efficient scaling of equipment is a demanding task that must be performed in parallel with increasing materials availability. We outline that 3–5 processing platforms are necessary to efficiently take the laboratory technology to a version that represents the lower end of the industrial scale. The machinery bridges the gap through firstly achieving improved ink efficiency without surface contact, followed by better ink efficiency at higher speeds, and finally large‐area processing at high speed with very high ink efficiency.
Gravure‐Printed ZnO in Fully Roll‐to‐Roll Printed Inverted Organic Solar Cells: Optimization of Adhesion and Performance
Authors: Vilkman Marja , Apilo Pälvi , Välimäki Marja , Ylikunnari Mari , Bernardi Andrea , Po Riccardo , Corso Gianni , Hast Jukka
Published: February 2015

We present a gravure printing process for zinc oxide (ZnO) nanoparticle ink to be used as a hole‐blocking layer in inverted organic solar cells, enabling the production of patterned devices with freedom of design. The printability of the ink is optimized in a pilot‐scale roll‐to‐roll (R2R) process, leading to smooth layers having a thickness of few tens of nanometers. The properties of the printed ZnO film are further optimized using R2R post‐printing plasma treatment, which leads to increased adhesion and power conversion efficiency (PCE). The functionality of the printed ZnO layer is demonstrated in fully R2R‐printed inverted solar cells showing high performance (2.9 % mean PCE).
Rational Design of Mesoporous Carbon Electrodes with High Mass Loading for Binder‐Free Supercapacitors
Authors: Zhang Xiang‐Qian , Dong Wei , Lu An‐Hui , Li Wen‐Cui
Published: February 2015

A three‐dimensional mesoporous carbon/nickel foam hybrid material has been prepared using an in situ solution growth approach, and its energy storage as a binder‐free supercapacitor electrode is explored. The nickel foam is chosen as an electrically conducting scaffold and also as a porous substrate for the growth of poly(benzoxazine‐co‐resol). After carbonization, tightly packed carbon layers are uniformly coated on the skeleton of the nickel foam. Such carbons show hierarchical porosity (micro‐, meso‐, macroporosity), a high surface area of 811 m2 g−1, and graphitic domains. These features allow easy access, rapid diffusion, and a high loading of ions, producing a material in which ion diffusion is faster than in bulk carbon and which is highly efficient in producing an increased double‐layer capacitance. The obtained electrodes exhibit an excellent capacitive behavior in KOH solutions, that is, low contact resistance, high specific capacitance (192 F g−1), and good rate performance. Furthermore, the three‐dimensional porous substrates facilitate a high mass loading of active materials, up to 21 mg cm−2, and per‐area capacitance of 1.18 F cm−2. This synthesis strategy is scalable and potentially usable for large‐scale production.
Gene‐Gene Interaction Among WNT Genes for Oral Cleft in Trios
Authors: Li Qing , Kim Yoonhee , Suktitipat Bhoom , Hetmanski Jacqueline B. , Marazita Mary L. , Duggal Priya , Beaty Terri H. , Bailey‐Wilson Joan E.
Published: February 2015

Genome‐wide association studies (GWAS) for nonsyndromic cleft lip with or without cleft palate (CL/P) have identified multiple genes as important in the etiology of this common birth defect. We performed a candidate gene/pathway analysis explicitly considering gene‐gene (G × G) interaction to further explore the etiology of CL/P. Animal models have shown the WNT signaling pathway plays an important role in mid‐facial development, and various genes in this pathway have been associated with nonsyndromic CL/P in previous studies. We propose a combined approach to search for possible G × G interactions using machine learning and regression‐based methods to test for interactions between genes in the WNT family, and between these genes and other genes identified by GWAS in case‐parent trios. Using this combined approach of regression‐based and machine learning methods in CL/P case‐parent trios, we found robust evidence of G × G interaction between markers in WNT5B and MAFB (empiric P‐values = 0.0076 among Asian trios and P‐values = 0.018 among European trios). Additional evidence for epistatic interaction between markers in WNT5A, IRF6, and C1orf107 was seen among Asian trios, and markers in the 8q24 region and WNT5B among European trios.
Emotional social support and access to care among older people living with HIV in rural China
Authors: Lin Chunqing , Li Li , Ji Guoping , Jie Wu
Published: February 2015

Objectives

Globally, the number of older people living with HIV (PLH) is growing. Additionally, older PLH are facing particular challenges related to accessing health care. The objective of this study is to investigate the older PLH's access to care and its relationship to emotional and tangible social support.

Methods

A cross‐sectional study was conducted among 225 PLH who were 50 years of age or older in Anhui, China. A computer‐assisted personal interview was used to collect the participants' demographic characteristics, perceived health status, and access to care. The following two dimensions of social support were measured: emotional support and tangible support. The association between emotional/tangible support and access to care was calculated using Pearson's/point‐biserial correlations and with multiple linear regression.

Results

Higher tangible support was reported by the participants who were married or living with a partner, those who had higher annual income levels, and those with better perceived health status. Emotional support was correlated with higher education, higher income, and better perceived health status. Multiple regression analyses showed that access to care was significantly associated with emotional support (β = 0.2807, p < 0.0001) but not with tangible support (β = −0.0183, p = 0.7922).

Conclusions

The study findings point to the importance of providing emotional support for older PLH. It is suggested that emotional support should be provided for older PLH in addition to tangible assistance, in order to engage them in treatment and care. Copyright © 2015 John Wiley & Sons, Ltd.
Development and testing of a European Union-wide farm-level carbon calculator
Authors: Tuomisto Hanna L , De Camillis Camillo , Leip Adrian , Nisini Luigi , Pelletier Nathan , Haastrup Palle
Published: February 2015

Direct greenhouse gas (GHG) emissions from agriculture accounted for approximately 10% of total European Union (EU) emissions in 2010. To reduce farming-related GHG emissions, appropriate policy measures and supporting tools for promoting low-C farming practices may be efficacious. This article presents the methodology and testing results of a new EU-wide, farm-level C footprint calculator. The Carbon Calculator quantifies GHG emissions based on international standards and technical specifications on Life Cycle Assessment (LCA) and C footprinting. The tool delivers its results both at the farm level and as allocated to up to 5 main products of the farm. In addition to the quantification of GHG emissions, the calculator proposes mitigation options and sequestration actions that may be suitable for individual farms. The results obtained during a survey made on 54 farms from 8 EU Member States are presented. These farms were selected in view of representing the diversity of farm types across different environmental zones in the EU. The results of the C footprint of products in the data set show wide range of variation between minimum and maximum values. The results of the mitigation actions showed that the tool can help identify practices that can lead to substantial emission reductions. To avoid burden-shifting from climate change to other environmental issues, the future improvements of the tool should include incorporation of other environmental impact categories in place of solely focusing on GHG emissions. Integr Environ Assess Manag 2015;11:404–416. © 2015 The Authors. Published by Wiley Periodicals, Inc. on behalf of SETAC.

Key Points

The methodology and testing results of a new European Union-wide, farm-level carbon calculator are presented. The Carbon Calculator reports life cycle assessment-based greenhouse gas emissions at farm and product levels and recommends farm- specific mitigation actions. Based on the results obtained from testing the tool in 54 farms in 8 European countries, it was found that the product-level carbon footprint results are comparable with those of other studies focusing on similar products. The results of the mitigation actions showed that the tool can help identify practices that can lead to substantial emission reductions.
Synergistic effects of atmospheric pressure plasma‐emitted components on DNA oligomers: a Raman spectroscopic study
Authors: Edengeiser Eugen , Lackmann Jan‐Wilm , Bründermann Erik , Schneider Simon , Benedikt Jan , Bandow Julia E. , Havenith Martina
Published: February 2015

Cold atmospheric‐pressure plasmas have become of increasing importance in sterilization processes especially with the growing prevalence of multi‐resistant bacteria. Albeit the potential for technological application is obvious, much less is known about the molecular mechanisms underlying bacterial inactivation. X‐jet technology separates plasma‐generated reactive particles and photons, thus allowing the investigation of their individual and joint effects on DNA. Raman spectroscopy shows that particles and photons cause different modifications in DNA single and double strands. The treatment with the combination of particles and photons does not only result in cumulative, but in synergistic effects. Profilometry confirms that etching is a minor contributor to the observed DNA damage in vitro.

Schematics of DNA oligomer treatment with cold atmospheric‐pressure plasma.

magnified image

Schematics of DNA oligomer treatment with cold atmospheric‐pressure plasma.
Reduction in Torsional Stiffness and Strength at the Proximal Tibia as a Function of Time Since Spinal Cord Injury
Authors: Edwards W Brent , Simonian Narina , Troy Karen L , Schnitzer Thomas J
Published: February 2015

Spinal cord injury (SCI) is characterized by marked bone loss and a high rate of low-energy fracture around regions of the knee. Changes in the mechanical integrity of bone after SCI are poorly defined, and a better understanding may inform approaches to prevent fractures. The purpose of this study was to quantify reductions in torsional stiffness and strength at the proximal tibia as a function of time since SCI. Sixty adults with SCI ranging from 0 to 50 years of duration and a reference group of 10 able-bodied controls received a CT scan of the proximal tibia. Measures of integral bone mineral were calculated for the total proximal tibia, and localized measures of cortical and trabecular bone mineral were calculated for the epiphysis, metaphysis, and diaphysis. Torsional stiffness (K) and strength (Tult) for the total proximal tibia were quantified using validated subject-specific finite element models. Total proximal tibia measures of integral bone mineral, K, and Tult decreased exponentially (r2 = 0.52 to 0.70) and reached a new steady state within 2.1 to 2.7 years after SCI. Whereas new steady-state values for integral bone mineral and K were 52% to 56% (p < 0.001) lower than the reference group, the new steady state for Tult was 69% (p < 0.001) lower than the reference group. Reductions in total proximal tibia measures occurred through a combination of trabecular and endocortical resorption, leaving a bone comprised primarily of marrow fat rather than hydroxyapatite. These findings illustrate that a short therapeutic window exists early (ie, 2 years) after SCI, during which bone-specific intervention may attenuate reductions in mechanical integrity and ultimately prevent SCI-related fragility fracture. © 2015 American Society for Bone and Mineral Research.
Association of Fetuin-A With Incident Fractures in Community-Dwelling Older Adults: The Cardiovascular Health Study
Authors: Fink Howard A , Bůžková Petra , Garimella Pranav S , Mukamal Kenneth J , Cauley Jane A , Kizer Jorge R , Barzilay Joshua I , Jalal Diana I , Ix Joachim H
Published: February 2015

Fetuin-A, a serum protein that regulates calcium mineralization, has been associated with bone mineral density (BMD) in several cross-sectional human studies, suggesting a possible beneficial effect on clinically important measures of bone health. Fetuin-A and incidence of subsequent fracture was assessed in 4714 men and women ≥65 years of age. Proportional hazards models were used to estimate risk of incident hip (hospital discharge ICD-9 codes) and composite fracture (hip, pelvis, humerus, or proximal forearm; hospital discharge ICD-9 codes and Medicare claims data). A total of 576 participants had an incident hip fracture (median follow-up 11.2 years) and 768 had an incident composite fracture (median follow-up 6.9 years). In unadjusted analyses, there was no association between fetuin-A (per SD increase) and risk of hip fracture (hazard ratio [HR], 0.96; 95% CI, 0.88 to 1.05) or composite fracture (HR, 0.99; 95% CI, 0.92 to 1.06). Results were not significantly changed after adjustment for potential confounding variables. Analyses modeling fetuin-A in quartiles or within a subset with available BMD measures also showed no statistically significant association with risk of hip or composite fracture. Though fetuin-A was positively associated with areal BMD in partially adjusted models (total hip: β, 0.013 g/cm2; 95% CI, 0.005 to 0.021; femoral neck: β, 0.011 g/cm2; 95% CI, 0.004 to 0.018; and lumbar spine: β, 0.007 g/cm2; 95% CI, 0.001 to 0.028), these associations were no longer significant after further adjustment for BMI and in final multivariate models. In this large sample of community-dwelling older adults, a small positive association between fetuin-A and areal BMD appeared attributable to confounding variables and we found no evidence of an association between fetuin-A and risk of clinical fracture. © 2015 American Society for Bone and Mineral Research © 2015 American Society for Bone and Mineral Research.
A novel CRTH2 antagonist: Single‐ and multiple‐dose tolerability, pharmacokinetics, and pharmacodynamics of ACT‐453859 in healthy subjects
Authors: Géhin Martine , Strasser Daniel S. , Zisowsky Jochen , Farine Hervé , Groenen Peter M.A. , Dingemanse Jasper , Sidharta Patricia N.
Published: February 2015

The chemoattractant receptor‐homologous molecule expressed on T‐helper 2 cells (CRTH2) is a G‐protein‐coupled receptor for prostaglandin D2, a key mediator in inflammatory disorders. In this randomized, double‐blind, placebo‐controlled study we investigated the single‐ and multiple‐dose tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) up to a dose of 800 mg once a day of ACT‐453859, a potent and selective CRTH2 antagonist. ACT‐453859 was moderately rapidly absorbed and followed a biphasic elimination pattern, with an elimination half‐life between 11 and 20 hours. Steady‐state conditions were reached after 1 day, and ACT‐453859 did not accumulate. Urinary excretion of unchanged ACT‐453859 did not exceed 1.4% of the administered dose. Administration of ACT‐453859 resulted in a dose‐dependent blockadeof CRTH2 on the surface of eosinophils. The maximum PD effect of ACT‐453859 was reached about 2.0 hours after dosing, which corresponded to the highest concentration at which PD were assessed. At steady state, 100 and 800 mg ACT‐453859 once a day resulted in blockade of CRTH2 over 24 hours. In this entry‐into‐humans study, ACT‐453859 showed good tolerability at all doses and a PK and PD profile compatible with once‐daily dosing.
Network spot‐checking games: Theory and application to toll enforcing in transportation networks
Authors: Borndörfer Ralf , Buwaya Julia , Sagnol Guillaume , Swarat Elmar
Published: February 2015

We introduce the class of spot‐checking games (SC games). These games model problems where the goal is to distribute fare inspectors over a toll network. In an SC game, the pure strategies of network users correspond to paths in a graph, and the pure strategies of the inspectors are subset of arcs to be controlled. Although SC games are not zero‐sum, we show that a Nash equilibrium can be computed by linear programming. The computation of a strong Stackelberg equilibrium (SSE) is more relevant for this problem and we give a mixed integer programming (MIP) formulation for this problem. We show that the computation of such an equilibrium is NP‐hard. More generally, we prove that it is NP‐hard to compute a SSE in a polymatrix game, even if the game is pairwise zero‐sum. Then, we give some bounds on the price of spite, which measures how the payoff of the inspector degrades when committing to a Nash equilibrium. Finally, we report computational experiments on instances constructed from real data, for an application to the enforcement of a truck toll in Germany. These numerical results show the efficiency of the proposed methods, as well as the quality of the bounds derived in this article. © 2015 Wiley Periodicals, Inc. NETWORKS, Vol. 65(4), 312–328 2015
Fast enclosure for the minimum norm least squares solution of the matrix equation AXB = C
Authors: Miyajima Shinya
Published: February 2015

Fast algorithms for enclosing the minimum norm least squares solution of the matrix equation AXB = C are proposed. To develop these algorithms, theories for obtaining error bounds of numerical solutions are established. The error bounds obtained by these algorithms are verified in the sense that all the possible rounding errors have been taken into account. Techniques for accelerating the enclosure and obtaining smaller error bounds are introduced. Numerical results show the properties of the proposed algorithms. Copyright © 2015 John Wiley & Sons, Ltd.
Cationic copolymerization of L,L‐lactide with hydroxyl substituted cyclic ethers
Authors: Basko Malgorzata , Bednarek Melania , Kubisa Przemyslaw
Published: February 2015

Cyclic ethers with 3‐, 4‐ and 5‐atoms in the ring containing hydroxymethyl substituents, acting as latent AB2 monomers, were copolymerized with L,L‐lactide by cationic mechanism with the aim of obtaining branched polylactide with multiple hydroxyl end‐groups. Hydroxymethyloxirane (glycidol) (three‐membered ring) was quite effective in introducing branching, resulting medium molecular weight polymers were characterized by GPC, NMR, MALDI‐TOF and thermal analysis methods. Hydroxymethyloxetane (three‐membered ring) also gave branched polymers although this comonomer was less effective in introducing branching than glycidol. Hydroxymethyloxolane (five‐membered ring) did not copolymerize, acting only as initiator of lactide polymerization; thus, resulting product was lactide homopolymer containing tetrahydrofuran moiety as head‐group. Copyright © 2015 John Wiley & Sons, Ltd.
Biodegradable and stimuli sensitive amphiphilic graft copolymers and their sol–gel phase transition behavior
Authors: Tamer Yasemin , Yıldırım Hüseyin
Published: February 2015

pH and temperature‐sensitive biodegradable poly(β‐aminoester)‐graft‐poly(ε‐caprolactone)‐block‐methoxy poly(ethylene glycol) (PBAE‐g‐PCL‐b‐mPEG) amphiphilic graft copolymers with different molecular weights were synthesized. The structure of these copolymers was adjusted by varying the feed ratios of ε‐caprolactone to methoxy poly(ethylene glycol)s (mPEG), amine and diacrylate monomer amounts and the molecular weight of mPEG. Aqueous solutions of these copolymers formed micelles at lower concentrations; however, the concentrated solutions showed a reversible sol–gel transition property depending on both pH and temperature changes under representative physiological conditions (pH 7.4, 37°C). The effects of the molecular weight of pH‐sensitive poly(β‐aminoester) block and mPEG group, the hydrophobic to hydrophilic block ratio (PCL/mPEG) and the concentration of the copolymer on the sol–gel transition were investigated. Proton nuclear magnetic resonance (1H NMR) and gel permeation chromatography measurements were used to characterize the structure of the synthesized copolymers. The self‐assemble behavior and critical micelle concentration of the amphiphilic copolymers were estimated in phosphate buffer solution using fluorescence spectroscopy. The gelling behavior was measured by using tube inversion method. At pH 7.4, all copolymer solutions prepared 20 wt% concentration indicated sol–gel transition with increasing temperature. In vitro degradation experiments displayed that the synthesized graft copolymers mostly degraded hydrolytically within 20 days under physiological conditions. In order to investigate the potential application of synthesized hydrogels in drug delivery, Methylene Blue was used and approximately 70% of the loaded amount was released in 120 hr. The findings indicate that obtained graft copolymers can be used as injectable biodegradable carriers for pharmaceutical drugs. Copyright © 2015 John Wiley & Sons, Ltd.
Photo‐responsive amphiphilic poly(α‐hydroxy acids) with pendent o‐nitrobenzyl ester constructed via copper‐catalyzed azide‐alkyne cycloaddition reaction
Authors: Liu Xiangyu , He Jingwen , Niu Yile , Li Yefei , Hu Ding , Xia Xinnian , Lu Yanbing , Xu Weijian
Published: February 2015

Photo‐responsive block copolymer mPEG‐b‐poly(Tyr)‐g‐NB was prepared by introduction of o‐nitrobenzyl ester group into the side chain of amphiphilic poly(ethylene glycol)‐b‐poly(α‐hydroxy acids) (mPEG‐b‐poly(Tyr)) containing pendent alkynyl group via copper‐catalyzed azide‐alkyne cycloaddition reaction. The amphiphilic mPEG‐b‐poly(Tyr) was synthesized via the ring‐opening polymerization of O‐carboxyanhydrides, with monomethoxy poly(ethylene glycol) (mPEG) as macroinitiator. The molecular structure, self‐assembly, and photo‐controlled release of the obtained mPEG‐b‐poly(Tyr)‐g‐NB were thoroughly investigated. mPEG‐b‐poly(Tyr)‐g‐NB could self‐assemble into spherical micelles in water and showed disassembly under UV light irradiation, which was demonstrated by means of UV‐vis spectroscopy, scan electron microscopes, and dynamic light scattering measurement. Fluorescence emission measurements demonstrated that Nile red, encapsulated by micelles, can be released upon UV irradiation. This study provides a convenient way to construct smart poly(α‐hydroxy acids)‐based nanocarriers for controlled release of hydrophobic drugs. Copyright © 2015 John Wiley & Sons, Ltd.
Waterborne polyurethane/NiAl‐LDH/ZnO composites with high antibacterial activity
Authors: Xiong Liang , Zhang Wei‐De , Shi Qing‐Shan , Mai Ai‐Ping
Published: February 2015

Novel waterborne polyurethane (WPU) composites based on NiAl‐LDH and ZnO were successfully synthesized by in‐situ polymerization. The nanostructured NiAl‐LDH/ZnO was first grafted by isophorone diisocyanate (IPDI), forming the NiAl‐LDH/ZnO‐NCO complex with ―NCO group on the surface, which promotes its homogeneous dispersion in WPU matrix. The microstructure and particle distribution of the composites were characterized. The mechanical properties and the water resistance of the composites were improved. Furthermore, the composites also exhibit significant antibacterial activity towards G(−) Escherichia coli and G(+) Staphylococcus aureus. Copyright © 2015 John Wiley & Sons, Ltd.
HOMEWORK MANAGEMENT SCALE: CONFIRMING THE FACTOR STRUCTURE WITH MIDDLE SCHOOL STUDENTS IN CHINA
Authors: Xu Jianzhong , Fan Xitao , Du Jianxia
Published: February 2015

This study presents a psychometric evaluation of the Homework Management Scale (HMS) for mathematics, consisting of five subscales for measuring ' homework management strategies. Confirmatory factor analyses were conducted with a sample of middle school students (N = 796). Results indicated that the factor structure of the Chinese version of the HMS for mathematics was consistent with the original one developed in the United States. Furthermore, the HMS and its subscales were correlated with related measures (i.e., homework purpose, homework behaviors, and learning strategies) in the theoretically expected directions. These findings suggest that Chinese version of the HMS is a valid multidimensional measure for mathematics homework at the middle school level. In addition, these findings strengthen the validity of the HMS, as China and United States represent two countries in East and West that differ with regard to their education system in general, and with homework practices in particular.
VALIDATION OF THE SOCIAL AND EMOTIONAL HEALTH SURVEY FOR FIVE SOCIOCULTURAL GROUPS: MULTIGROUP INVARIANCE AND LATENT MEAN ANALYSES
Authors: You Sukkyung , Furlong Michael , Felix Erika , O'Malley Meagan
Published: February 2015

Social‐emotional health influences youth developmental trajectories and there is growing interest among educators to measure the social‐emotional health of the students they serve. This study replicated the psychometric characteristics of the Social Emotional Health Survey (SEHS) with a diverse sample of high school students (Grades 9–12; N = 14,171), and determined whether the factor structure was invariant across sociocultural and gender groups. A confirmatory factor analysis (CFA) tested the fit of the previously known factor structure, and then structural equation modeling was used to test invariance across sociocultural and gender groups through multigroup CFAs. Results supported the SEHS measurement model, with full invariance of the SEHS higher‐order structure for all five sociocultural groups. There were no moderate effect size or higher group differences on the overall index for sociocultural or gender groups, which lends support to the eventual development of common norms and universal interpretation guidelines.
Identification of new phosphorylation sites of AMPA receptors in the rat hippocampus—A resource for neuroscience research
Authors: Ghafari Maryam , Keihan Falsafi Soheil , Höger Harald , Bennett Keiryn L. , Lubec Gert
Published: February 2015

Purpose

AMPA (alpha‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionic acid) receptors (AMPARs) are glutamate‐gated ion channels that mediate the majority of fast excitatory synaptic transmissions in the mammalian brain. A series of phosphorylation sites have been predicted or identified and knowledge on phosphorylations is mandatory for understanding receptor biology and functions.

Experimental design

Immunoprecipitation from extracted hippocampal rat proteins was carried out using an antibody against the AMPAR GluA1 subunit, followed by identification of GluA1 and binding partners by MS. Bands from SDS‐PAGE were picked, peptides were generated by trypsin and chymotrypsin digestion and identified by MS/MS (LTQ Orbitrap Velos).

Results

Using Mascot as a search engine, phosphorylation sites S506, S645, S720, S849, S863, S895, T858, Y228, Y419, and T734 were found on GluA1; S357, S513, S656, S727, T243, T420, T741, Y 143, Y301,Y426 on GluA2; S301, S516, S657, S732, T222, and T746 were observed on GluA3; and S514, S653 was phosphorylated on GluA4.

Conclusions and clinical relevance

A series of additional protein modifications were observed and in particular, tyrosine and tryptophan nitrations on GluA1 were detected that may raise questions on additional regulation mechanisms for AMPARs in addition to phosphorylations. The findings are relevant for interpretation of previous work and design of future studies using AMPAR serving as a resource for neuroscience research and indeed, phosphorylations and PTMs per se would have to be respected when neuropathological and neurological disorders are being studied.
Ballistic conduction in macroscopic non‐periodic lattices
Authors: Wang Chumin , Ramírez Carlos , Sánchez Fernando , Sánchez Vicenta
Published: February 2015

In this paper, the dc electronic transport at zero temperature in aperiodic systems with macroscopic length is studied by using a real‐space renormalization plus convolution method developed for the Kubo–Greenwood formula within the tight‐binding formalism. We analytically prove the existence of transparent states in several generalized Fibonacci lattices, as well as in segmented linear chains, where they always appear if the number of bonds in each segment is even, regardless the ordering of segments. For two‐dimensional square‐lattice tapes with a periodic or non‐periodic Fano‐impurity plane, we found a novel ballistic transport state in the dc conductance spectra.
A regression tree approach to identifying subgroups with differential treatment effects
Authors: Loh Wei‐Yin , He Xu , Man Michael
Published: February 2015

In the fight against hard‐to‐treat diseases such as cancer, it is often difficult to discover new treatments that benefit all subjects. For regulatory agency approval, it is more practical to identify subgroups of subjects for whom the treatment has an enhanced effect. Regression trees are natural for this task because they partition the data space. We briefly review existing regression tree algorithms. Then, we introduce three new ones that are practically free of selection bias and are applicable to data from randomized trials with two or more treatments, censored response variables, and missing values in the predictor variables. The algorithms extend the generalized unbiased interaction detection and estimation (GUIDE) approach by using three key ideas: (i) treatment as a linear predictor, (ii) chi‐squared tests to detect residual patterns and lack of fit, and (iii) proportional hazards modeling via Poisson regression. Importance scores with thresholds for identifying influential variables are obtained as by‐products. A bootstrap technique is used to construct confidence intervals for the treatment effects in each node. The methods are compared using real and simulated data. Copyright © 2015 John Wiley & Sons, Ltd.
Position‐based adaptive quantization for target location estimation in wireless sensor networks using one‐bit data
Authors: Liu Guiyun , Liu Hua , Chen Hongbin , Zhou Chao , Shu Lei
Published: February 2015

The problem of target location estimation in a wireless sensor network is considered, where due to the bandwidth and power constraints, each sensor only transmits one‐bit information to its fusion center. To improve the performance of estimation, a position‐based adaptive quantization scheme for target location estimation in wireless sensor networks is proposed to make a good choice of quantizer' thresholds. By the proposed scheme, each sensor node dynamically adjusts its quantization threshold according to a kind of position‐based information sequences and then sends its one‐bit quantized version of the original observation to a fusion center. The signal intensity received at local sensors is modeled as an isotropic signal intensity attenuation model. The position‐based maximum likelihood estimator as well as its corresponding position‐based Cramér–Rao lower bound are derived. Numerical results show that the position‐based maximum likelihood estimator is more accurate than the classical fixed‐quantization maximum likelihood estimator and the position‐based Cramér–Rao lower bound is less than its fixed‐quantization Cramér‐Rao lower bound. Copyright © 2015 John Wiley & Sons, Ltd.
Exploring hypertension genome‐wide association studies findings and impact on pathophysiology, pathways, and pharmacogenetics
Authors: Cabrera Claudia P , Ng Fu Liang , Warren Helen R , Barnes Michael R , Munroe Patricia B , Caulfield Mark J
Published: February 2015

Hypertension is a major risk factor for global mortality. Recent genome‐wide association studies (GWAS) have led to successful identification of many genetic loci influencing blood pressure, although these studies account for less than 5% of heritability. While genetic discovery efforts continue, it is timely to pause and reflect on what information has been gained to date from reported loci. Knowledge from GWAS findings inform our understanding of the pathways and pleiotropy underpinning hypertension and aid in the identification of potential druggable targets. By reviewing blood pressure loci we aim to determine how much potential the current observations have for future clinical utility. WIREs Syst Biol Med 2015, 7:73–90. doi: 10.1002/wsbm.1290

This article is categorized under:

Translational, Genomic, and Systems Medicine > Translational Medicine
Synthesis and Photoluminescence Properties of the Red‐Emitting Phosphor Mg3(BN2)N Doped with Eu2+
Authors: Schölch Jessica , Dierkes Tobias , Enseling David , Ströbele Markus , Jüstel Thomas , Meyer H.‐Jürgen
Published: February 2015

Mg3(BN2)N was prepared by solid state metathesis reactions and several europium (Eu2+) doped samples were prepared to discover novel red‐emitting photoluminescent (PL) materials. It turned out that the undoped and doped samples showed very broad deep‐red photoluminescence ranging from about 500 nm into the near infrared. Due to the similar spectra of the undoped and doped samples and unusually high FWHM values of about 5780 cm–1 we conclude that the luminescence process originates from defect sites. This was confirmed by decay measurements which show that the decay constants for all samples were in the range of several milliseconds.