bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics of suspended solids affect bifenthrin toxicity to the calanoid copepods Eurytemora affinis and Pseudodiaptomus forbesi
Authors: Parry Emily , Lesmeister Sarah , Teh Swee , Young Thomas M.
Published: May 2015

Bifenthrin is a pyrethroid pesticide that is highly toxic to aquatic invertebrates. The dissolved concentration is generally thought to be the best predictor of acute toxicity. However, for the filter-feeding calanoid copepods Eurytemora affinis and Pseudodiaptomus forbesi, ingestion of pesticide-bound particles could prove to be another route of exposure. The present study investigated bifenthrin toxicity to E. affinis and P. forbesi in the presence of suspended solids from municipal wastewater effluent and surface water of the San Francisco (CA, USA) Estuary. Suspended solids mitigated the toxicity of total bifenthrin to E. affinis and P. forbesi, but mortality was higher than what would be predicted from dissolved concentrations alone. The results indicate that the toxicity and bioavailability of particle-associated bifenthrin was significantly correlated with counts of 0.5-µm to 2-µm particle sizes. Potential explanations could include direct ingestion of bifenthrin-bound particles, changes in food consumption and feeding behavior, and physical contact with small particles. The complex interactions between pesticides and particles of different types and sizes demonstrate a need for future ecotoxicological studies to investigate the role of particle sizes on aquatic organisms. Environ Toxicol Chem 2015;34:2302–2309. © 2015 SETAC
Inefficiency in macromolecular transport of SCS‐based microcapsules affects viability of primary human mesenchymal stem cells but not of immortalized cells
Authors: Sanz‐Nogués Clara , Horan Jason , Thompson Kerry , Howard Linda , Ryan Gerard , Kassem Moustapha , O'Brien Timothy
Published: May 2015

Microcapsules made of sodium cellulose sulphate (SCS) and poly‐diallyl‐dimethyl‐ammonium chloride (pDADMAC) have been employed to encapsulate a wide range of established cell lines for several applications. However, little is known about the encapsulation of primary cells including human mesenchymal stem cells (hMSCs). Human MSCs are of interest in regenerative medicine applications due to pro‐angiogenic, anti‐inflammatory and immunomodulatory properties, which result from paracrine effects of this cell type. In the present work we have encapsulated primary hMSCs and hMSC‐TERT immortalized cells and compared their behavior and in vitro angiogenic potential. We found that, although both cell types were able to secret angiogenic factors such as VEGF, there was a marked reduction of primary hMSC viability compared to hMSC‐TERT cells when cultured in these microcapsules. Moreover, this applied to other primary cell cultures such as primary human fibroblasts but not to other cell lines such as human embryonic kidney 293 (HEK293) cells. We found that the microcapsule membrane had a molecular weight cut‐off below a critical size, which caused impairment in the diffusion of essential nutrients and had a more detrimental effect on the viability of primary cell cultures compared to cell lines and immortalized cells. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3676–3688, 2015.
Chondroprotective effect of zinc oxide nanoparticles in conjunction with hypoxia on bovine cartilage‐matrix synthesis
Authors: Mirza Eraj Humayun , Pan‐Pan Chong , Wan Ibrahim Wan Mohd Azhar Bin , Djordjevic Ivan , Pingguan‐Murphy Belinda
Published: May 2015

Articular cartilage is a tissue specifically adapted to a specific niche with a low oxygen tension (hypoxia), and the presence of such conditions is a key factor in regulating growth and survival of chondrocytes. Zinc deficiency has been linked to cartilage‐related disease, and presence of Zinc is known to provide antibacterial benefits, which makes its inclusion attractive in an in vitro system to reduce infection. Inclusion of 1% zinc oxide nanoparticles (ZnONP) in poly octanediol citrate (POC) polymer cultured in hypoxia has not been well determined. In this study we investigated the effects of ZnONP on chondrocyte proliferation and matrix synthesis cultured under normoxia (21% O2) and hypoxia (5% O2). We report an upregulation of chondrocyte proliferation and sulfated glycosaminoglycan (S‐GAG) in hypoxic culture. Results demonstrate a synergistic effect of oxygen concentration and 1% ZnONP in up‐regulation of anabolic gene expression (Type II collagen and aggrecan), and a down regulation of catabolic (MMP‐13) gene expression. Furthermore, production of transcription factor hypoxia‐inducible factor 1A (HIF‐1A) in response to hypoxic condition to regulate chondrocyte survival under hypoxia is not affected by the presence of 1% ZnONP. Presence of 1% ZnONP appears to act to preserve homeostasis of cartilage in its hypoxic environment. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3554–3563, 2015.
Cardiac‐Specific Disruption of Bin1 in Mice Enables a Model of Stress‐ and Age‐Associated Dilated Cardiomyopathy
Authors: Laury‐Kleintop Lisa D. , Mulgrew Jennifer R. , Heletz Ido , Nedelcoviciu Radu Alexandru , Chang Mee Young , Harris David M. , Koch Walter J. , Schneider Michael D. , Muller Alexander J. , Prendergast George C.
Published: May 2015

Non‐compensated dilated cardiomyopathy (DCM) leading to death from heart failure is rising rapidly in developed countries due to aging demographics, and there is a need for informative preclinical models to guide the development of effective therapeutic strategies to prevent or delay disease onset. In this study, we describe a novel model of heart failure based on cardiac‐specific deletion of the prototypical mammalian BAR adapter‐encoding gene Bin1, a modifier of age‐associated disease. Bin1 deletion during embryonic development causes hypertrophic cardiomyopathy and neonatal lethality, but there is little information on how Bin1 affects cardiac function in adult animals. Here we report that cardiomyocyte‐specific loss of Bin1 causes age‐associated dilated cardiomyopathy (DCM) beginning by 8–10 months of age. Echocardiographic analysis showed that Bin1 loss caused a 45% reduction in ejection fraction during aging. Younger animals rapidly developed DCM if cardiac pressure overload was created by transverse aortic constriction. Heterozygotes exhibited an intermediate phenotype indicating Bin1 is haplo‐insufficient to sustain normal heart function. Bin1 loss increased left ventricle (LV) volume and diameter during aging, but it did not alter LV volume or diameter in hearts from heterozygous mice nor did it affect LV mass. Bin1 loss increased interstitial fibrosis and mislocalization of the voltage‐dependent calcium channel Cav1.2, and the lipid raft scaffold protein caveolin‐3, which normally complexes with Bin1 and Cav1.2 in cardiomyocyte membranes. Our findings show how cardiac deficiency in Bin1 function causes age‐ and stress‐associated heart failure, and they establish a new preclinical model of this terminal cardiac disease. J. Cell. Biochem. 116: 2541–2551, 2015. © 2015 Wiley Periodicals, Inc.
A Distinct Role for Interleukin‐6 as a Major Mediator of Cellular Adjustment to an Altered Culture Condition
Authors: Son Hwa‐Kyung , Park Iha , Kim Jue Young , Kim Do Kyeong , Illeperuma Rasika P. , Bae Jung Yoon , Lee Doo Young , Oh Eun‐Sang , Jung Da‐Woon , Williams Darren R. , Kim Jin
Published: May 2015

Tissue microenvironment adjusts biological properties of different cells by modulating signaling pathways and cell to cell interactions. This study showed that epithelial–mesenchymal transition (EMT)/ mesenchymal–epithelial transition (MET) can be modulated by altering culture conditions. HPV E6/E7‐transfected immortalized oral keratinocytes (IHOK) cultured in different media displayed reversible EMT/MET accompanied by changes in cell phenotype, proliferation, gene expression at transcriptional, and translational level, and migratory and invasive activities. Cholera toxin, a major supplement to culture medium, was responsible for inducing the morphological and biological changes of IHOK. Cholera toxin per se induced EMT by triggering the secretion of interleukin 6 (IL‐6) from IHOK. We found IL‐6 to be a central molecule that modulates the reversibility of EMT based not only on the mRNA level but also on the level of secretion. Taken together, our results demonstrate that IL‐6, a cytokine whose transcription is activated by alterations in culture conditions, is a key molecule for regulating reversible EMT/MET. This study will contribute to understand one way of cellular adjustment for surviving in unfamiliar conditions. J. Cell. Biochem. 116: 2552–2562, 2015. © 2015 The Authors.Journal of Cellular BiochemistryPublished by Wiley Periodicals, Inc.
Japanese encephalitis associated acute encephalitis syndrome cases in West Bengal, India: A sero‐molecular evaluation in relation to clinico‐pathological spectrum
Authors: Sarkar Arindam , Datta Somenath , Pathak Bani K. , Mukhopadhyay Subhra K. , Chatterjee Shyamalendu
Published: May 2015

Japanese encephalitis (JE) is a major public health problem in Asia and worldwide and it is responsible mainly for viral acute encephalitis syndrome (AES). The sole etiologic agent of JE is Japanese encephalitis virus (JEV). Although JE/AES cases have been regarded traditionally as a disease of children, a growing number of patients with JE/AES cases are also seen in the adult age group every year in the state of West Bengal, India in spite of vaccination. Therefore, a systematic study was performed to differentiate and characterize the clinico‐pathological parameters and viral diversity among the patients of different age groups. Viral diversity was also evaluated from the JE/AES cases, depending on their disease severity. A total of 441 JE/AES cases were included in this study. By MAC–ELISA, 111 samples were found JEV IgM positive and among the IgM negative cases, 26 samples were found RT–PCR positive against JEV infection. Neck rigidity, abnormal behavior, convulsion, protein in CSF, WBC in CSF, and aspartate transaminase in blood differed significantly among the patients of pediatric‐adolescent and adult group in both IgM positive and RT–PCR positive cases. Viral diversity was increased significantly in the pediatric‐adolescent group compared to adult patients. Interestingly, with the rise in disease severity the viral diversity was found to be increased among the patients, irrespective of their age distribution. Based on clinico‐pathological parameters and analysis of viral diversity, it can be concluded that viral diversity which occurs naturally is likely to affect disease severity, especially in the patients of pediatric‐adolescent group. J. Med. Virol. 87:1258–1267, 2015. © 2015 Wiley Periodicals, Inc.
Early osteoarthritis of the trapeziometacarpal joint is not associated with joint instability during typical isometric loading
Authors: Halilaj Eni , Moore Douglas C. , Patel Tarpit K. , Ladd Amy L. , Weiss Arnold‐Peter C. , Crisco Joseph J.
Published: May 2015

The saddle‐shaped trapeziometacarpal (TMC) joint contributes importantly to the function of the human thumb. A balance between mobility and stability is essential in this joint, which experiences high loads and is prone to osteoarthritis (OA). Since instability is considered a risk factor for TMC OA, we assessed TMC joint instability during the execution of three isometric functional tasks (key pinch, jar grasp, and jar twist) in 76 patients with early TMC OA and 44 asymptomatic controls. Computed tomography images were acquired while subjects held their hands relaxed and while they applied 80% of their maximum effort for each task. Six degree‐of‐freedom rigid body kinematics of the metacarpal with respect to the trapezium from the unloaded to the loaded task positions were computed in terms of a TMC joint coordinate system. Joint instability was expressed as a function of the metacarpal translation and the applied force. We found that the TMC joint was more unstable during a key pinch task than during a jar grasp or a jar twist task. Sex, age, and early OA did not have an effect on TMC joint instability, suggesting that instability during these three tasks is not a predisposing factor in TMC OA. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1639–1645, 2015.
3‐D localization of non‐radioactive strontium in osteoarthritic bone: Role in the dynamic labeling of bone pathological changes
Authors: Panahifar Arash , Cooper David M.L. , Doschak Michael R.
Published: May 2015

The study objective was to visualize regions of bone that undergo pathological mineralization and/or remodeling during pathogenesis of osteoarthritis, by employing non‐radioactive strontium as a dynamic tracer of bone turnover. Post traumatic osteoarthritis was surgically induced in skeletally mature rats, followed by in vivo micro‐CT imaging for 12 weeks to assess bone micro‐structural changes. Rats either received strontium ranelate daily for the entire course of study or only last 10 days before euthanization. Distribution of strontium in bone was assessed in two and three dimensions, using electron probe micro‐analysis (EPMA) and synchrotron dual energy K‐edge subtraction micro‐CT (SRμCT), respectively. Considerable early formation of osteophytes around the collateral ligament attachments and margins of articulating surfaces were observed, followed by subchondral sclerosis at the later stages. Accordingly, strontium was heavily incorporated by mineralizing osteophytes at 4, 8, and 12 weeks post‐surgery, whereas subchondral bone only incorporated strontium between weeks 8–12.This study showed low dose stable strontium can effectively serve as a dynamic tracer of bone turnover to study pathological bone micro‐structural changes, at resolution higher than nuclear medicine. Co‐administration of strontium during therapeutic drug intervention may show enormous utility in assessing the efficacy of those compounds upon adaptive bone physiology. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1655–1662, 2015.
Genipin crosslinking of cartilage enhances resistance to biochemical degradation and mechanical wear
Authors: McGann Megan E. , Bonitsky Craig M. , Jackson Mariah L. , Ovaert Timothy C. , Trippel Stephen B. , Wagner Diane R.
Published: May 2015

Collagen crosslinking enhances many beneficial properties of articular cartilage, including resistance to chemical degradation and mechanical wear, but many crosslinking agents are cytotoxic. The purpose of this study was to evaluate the effectiveness of genipin, a crosslinking agent with favorable biocompatibility and cytotoxicity, as a potential treatment to prevent the degradation and wear of articular cartilage. First, the impact of genipin concentration and treatment duration on the viscoelastic properties of bovine articular cartilage was quantified. Next, two short‐term (15 min) genipin crosslinking treatments were chosen, and the change in collagenase digestion, cartilage wear, and the friction coefficient of the tissue with these treatments was measured. Finally, chondrocyte viability after exposure to these genipin treatments was assessed. Genipin treatment increased the stiffness of healthy, intact cartilage in a dose‐dependent manner. The 15‐min crosslinking treatments improved cartilage's resistance to both chemical degradation, particularly at the articular surface, and to damage due to mechanical wear. These enhancements were achieved without sacrificing the low coefficient of friction of the tissue and at a genipin dose that preserved chondrocyte viability. The results of this study suggest that collagen crosslinking via genipin may be a promising preventative treatment to slow the degradation of cartilage. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1571–1579, 2015.
Therapeutic opportunities to prevent post‐traumatic arthritis: Lessons from the natural history of arthritis after articular fracture
Authors: Olson Steven A. , Furman Bridgette D. , Kraus Virginia B. , Huebner Janet L. , Guilak Farshid
Published: May 2015

An estimated 12% of patients seeking surgical intervention for symptomatic arthritis have an etiology of post‐traumatic arthritis (PTA). The onset of PTA is rapid in the setting of articular fracture (AF). The investigation began with development of a murine model of a closed AF that develops PTA. In the process of characterizing this model a technique was developed for assessing quantitative synovial fluid biomarker concentrations. The work began with observations of the natural history of PTA development in the C57BL/6 strain of mice. A species of mice (MRL/MpJ) was found that is protected from PTA after AF. Further work identified key differences between mouse strains that did and did not develop PTA. This knowledge led to an intervention based on anti‐cytokine (interleukin 1 receptor antagonist, (IL‐1Ra) delivery in the C57BL/6 strain of mice that successfully prevented PTA following AF. This success in preventing PTA in the murine model has elucidated several important clinical implications: 1) Pro‐inflammatory cytokines play an important role in the development of PTA after joint injury, 2) Pharmacologic intervention can lessen the severity of PTA after an AF, and 3) The murine AF model of joint injury provides a novel means of studying mechanisms of PTA development. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1266–1277, 2015.
The fractionated dipole antenna: A new antenna for body imaging at 7 Tesla
Authors: Raaijmakers Alexander J.E. , Italiaander Michel , Voogt Ingmar J. , Luijten Peter R. , Hoogduin Johannes M. , Klomp Dennis W.J. , van den Berg Cornelis A.T.
Published: May 2015

Purpose

Dipole antennas in ultrahigh field MRI have demonstrated advantages over more conventional designs. In this study, the fractionated dipole antenna is presented: a dipole where the legs are split into segments that are interconnected by capacitors or inductors.

Methods

A parameter study has been performed on dipole antenna length using numerical simulations. A subsequent simulation study investigates the optimal intersegment capacitor/inductor value. The resulting optimal design has been constructed and compared to a previous design, the single‐side adapted dipole (SSAD) by simulations and measurements. An array of eight elements has been constructed for prostate imaging on four subjects (body mass index 20–27.5) using 8 × 2 kW amplifiers.

Results

For prostate imaging at 7T, lowest peak local specific‐absorption rate (SAR) levels are achieved if the antenna is 30 cm or longer. A fractionated dipole antenna design with inductors between segments has been chosen to achieve even lower SAR levels and more homogeneous receive sensitivities.

Conclusion

With the new design, good quality prostate images are acquired. SAR levels are reduced by 41% to 63% in comparison to the SSAD. Coupling levels are moderate (average nearest neighbor: −14.6 dB) for each subject and prostate
levels range from 12 to 18 μT. Magn Reson Med 75:1366–1374, 2016. © 2015 Wiley Periodicals, Inc.
Influence of water and fat heterogeneity on fat‐referenced MR thermometry
Authors: Baron Paul , Deckers Roel , Bouwman Job G. , Bakker Chris J. G. , de Greef Martijn , Viergever Max A. , Moonen Chrit T. W. , Bartels Lambertus W.
Published: May 2015

Purpose

To investigate the effect of the aqueous and fatty tissue magnetic susceptibility distribution on absolute and relative temperature measurements as obtained directly from the water/fat (w/f) frequency difference.

Methods

Absolute thermometry was investigated using spherical phantoms filled with pork and margarine, which were scanned in three orthogonal orientations. To evaluate relative fat referencing, multigradient echo scans were acquired before and after heating pork tissue via high‐intensity focused ultrasound (HIFU). Simulations were performed to estimate the errors that can be expected in human breast tissue.

Results

The sphere experiment showed susceptibility‐related errors of 8.4°C and 0.2°C for pork and margarine, respectively. For relative fat referencing measurements, fat showed pronounced phase changes of opposite polarity to aqueous tissue. The apparent mean temperature for a numerical breast model assumed to be 37°C was 47.2 ± 21.6°C. Simulations of relative fat referencing for a HIFU sonication (ΔT = 29.7°C) yielded a maximum temperature error of 6.6°C compared with 2.5°C without fat referencing.

Conclusion

Variations in the observed frequency difference between water and fat are largely due to variations in the w/f spatial distribution. This effect may lead to considerable errors in absolute MR thermometry. Additionally, fat referencing may exacerbate rather than correct for proton resonance frequency shift–temperature measurement errors. Magn Reson Med 75:1187–1197, 2016. © 2015 Wiley Periodicals, Inc.
Velocity‐selective magnetization‐prepared non‐contrast‐enhanced cerebral MR angiography at 3 Tesla: Improved immunity to B0/B1 inhomogeneity
Authors: Qin Qin , Shin Taehoon , Schär Michael , Guo Hua , Chen Hanwei , Qiao Ye
Published: May 2015

Purpose

To develop a Fourier‐transform based velocity‐selective (VS) pulse train that offers improved robustness to B0/B1 inhomogeneity for non‐contrast‐enhanced cerebral MR angiography (MRA) at 3 Tesla (T).

Methods

VS pulse train I and II with different saturation bands are proposed to incorporate paired and phase cycled refocusing pulses. Their sensitivity to B0/B1 inhomogeneity was estimated through simulation and compared with a single refocused VS pulse train. The implementation was compared to standard time of flight (TOF) among eight healthy subjects.

Results

In contrast to single refocused VS pulse train, the simulated VS profiles from proposed pulse trains indicate much improved immunity to field inhomogeneity in the brain at 3T. Successive application of two identical VS pulse trains yields a better suppression of static tissue at the cost of 20∼30% signal loss within large vessels. Average relative contrast ratios of major cerebral arterial segments applying both pulse train I and II with two preparations are 0.81 ± 0.06 and 0.81 ± 0.05, respectively, significantly higher than 0.67 ± 0.07 of TOF‐MRA. VS MRA, in particular, the pulse train II with the narrower saturation band, depicts more small vessels with slower flow.

Conclusion

VS magnetization‐prepared cerebral MRA was demonstrated among normal subjects on a 3T scanner. Magn Reson Med 75:1232–1241, 2016. © 2015 Wiley Periodicals, Inc.
Effect of mixed size particles reinforcing on the thermal and dynamic mechanical properties of Al2O3/PPS composites
Authors: Çoban Onur , Bora Mustafa Özgür , Sinmazçelik Tamer
Published: May 2015

Thermal and dynamic mechanical properties of polyphenylene sulfide (PPS) composites that were reinforced with different sized alumina (Al2O3) particles were studied. These composites were manufactured with two different sizes of Al2O3 particles 1 and 63 µm, using microcompounding and injection molding. Monosized Al2O3 particles reinforced up to 25 wt% loading content and mixed size Al2O3 particles reinforced at 15 wt% loading content as following particle weight proportions: 75% × 63 μm + 25% × 1 μm, 50% × 63 μm + 50% × 1 μm, 25% × 63 μm + 75% × 1 μm. Particle distribution investigations were performed by microcomputerized tomography (micro‐CT). Thermal properties were analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) methods and also dynamic mechanical properties were investigated by dynamic mechanical thermal analysis (DMTA) method. The results showed that mixed size Al2O3 particle reinforced composites showed a great enhancement in dynamic mechanical properties without significant change in thermal properties. It was concluded that mixed size particles showed a great synergy to give better results compared with monosized particle reinforced composites. POLYM. COMPOS., 37:3219–3227, 2016. © 2015 Society of Plastics Engineers
Mechanical, dynamic mechanical, and thermal characterization of fly ash and nanostructured fly ash‐waste polyethylene/high‐density polyethylene blend composites
Authors: Satapathy Sukanya , Bihari Nando Golok
Published: May 2015

Disposal of polyethylene used as carry bags is the greatest challenge increasing day by day. Composite materials were prepared by mixing Fly ash (FA) and nanostructured fly ash (NFA) from thermal power station as filler and blends of Waste polyethylene (WPE)(carry bags) collected from municipal solid waste (MSW) with virgin high‐density polyethylene (HDPE) as matrix. Different modifications were induced to improve the overall properties of these composites. At first, the WPE/HDPE blend matrix was modified by grafting with maleic anhydride (MA) and the composite prepared with FA/NFA. Then, the WPE/HDPE‐FA/NFA composite as a whole was treated with electron beam irradiation at 250 kGy radiation dose and finally the FA/NFA filler was treated with radiation dose of 250 kGy and the composite prepared. Significant enhancement in tensile strength, flexural strength, flexural modulus, and hardness are observed for MA modified and irradiated composites, the increase being more prominent in irradiated composites. Furthermore, an increase in storage/loss moduli with enhanced thermal stability was observed with the addition of FA/NFA and upon modifications. The analysis of the tensile fractured surfaces by scanning electron microscopy was in well correlation with the mechanical properties obtained. In summary, after analyzing the effects of the three different modifications on mechanical, dynamic mechanical and thermal properties, the irradiation on to the WPE/HDPE‐FA/NFA composites investigated was selected as the most appropriate for future applications. POLYM. COMPOS., 37:3256–3268, 2016. © 2015 Society of Plastics Engineers
Thermomechanical properties of styrene‐butyl acrylate/organo‐silica nanocomposite films prepared by seed emulsion polymerization
Authors: Ahmed Abd El‐Shafey I. , Hussain Ahmed I. , El‐Masry Ahmed M. , Saleh Ahmed
Published: May 2015

Organo‐silica nanoparticles were prepared by sol–gel technique of triethoxyvinylsilane (VTES) in aqueous solution. The vinyl groups located on the surface of organo‐silica were used to induce the polymerization process and the encapsulation into styrene‐butyl acrylate copolymer emulsion. The prepared latex samples were characterized using FTIR, 1HNMR, UV–visible, thermal analysis, field emission‐SEM and TEM. Results of TGA revealed that nanosilica has retarded the decomposition of nanocomposite polymers with at least 10°C higher than that of pure emulsions. DSC has shown an increase in the nanosilica ratio up to 5% which leads to a dramatic decrease in the glass transition (Tg) of nanocomposite polymer due to the formation of silica nanoparticles homopolymer. DMTA results indicated that the storage modulus of pure polymer is less than nanocomposite, which proves the reinforcing role of nanosilica in the matrix of polymer. Water resistance and UV‐blocking ability have improved by introducing the nanosilica into the matrix of prepared polymer. POLYM. COMPOS., 38:61–67, 2017. © 2015 Society of Plastics Engineers
Enhanced toughness of multilayer graphene‐filled poly(VInyl chloride) composites prepared using melt‐mixing method
Authors: Wang Han , Xie Guiyuan , Yang Cheng , Zheng Yaxuan , Ying Zhe , Ren Wencai , Zeng You
Published: May 2015

In order to improve toughness of rigid poly(vinyl chloride) (PVC), we prepared multilayer graphene (MLG) filled PVC composites through conventional melt‐mixing methods by taking advantages of easy dispersion and high flexibility of graphene. Microstructure, static, and dynamic mechanical properties of the MLG/PVC composites were investigated in details. We found that a small amount of MLG loadings (0.36 wt%) could greatly increase tensile fracture toughness and impact strength of the MLG/PVC composites, which is mainly attributed to high flexibility of the crumpled MLG throughout PVC matrix. Moreover, the presence of MLG can weaken intermolecular interactions and improve segmental motion of PVC chains, consequently resulting in low glass transition temperature and high toughness of the MLG/PVC composites. By virtue of its enhanced toughness and easy operation, the MLG/PVC composites show great potential to be used as high‐performance composites in many fields. POLYM. COMPOS., 38:138–146, 2017. © 2015 Society of Plastics Engineers
Fritz Haber und der “Krieg der Chemiker”
Authors: Friedrich Bretislav
Published: May 2015

Der Physikochemiker Fritz Haber (1868–1934) ging für sein Ammoniak‐Syntheseverfahren zur Herstellung von künstlichem Dünger (“Brot aus der Luft”) in die Geschichte ein. Das Haber‐Bosch‐Verfahren wurde aber ebenso wichtig für die Erzeugung von Schießpulver. Während des ersten Weltkriegs entwickelte Haber Giftgaswaffen für die deutschen Truppen und wurde deswegen auch als “Vater des Gaskrieges” bekannt. Der erste Weltkrieg wird auch als “Krieg der Chemiker” bezeichnet. 1933 weigerte sich Haber, die Rassengesetze der Nazis auszuführen und trat aus Protest zurück. Er verlies Deutschland und starb wenige Monate später in der Schweiz.
Photoionization of cobalt impurities in zinc oxide
Authors: Ivanov Vitalii Yu. , Godlewski Marek , Dejneka Alexander
Published: May 2015

Electron Spin Resonance investigations allow to attribute a broad absorption band below the band‐to‐band transition of ZnO:Co to photoionization transitions of Co‐ions. This absorption, with the onset at about 2.4–2.6 eV, is due to cobalt recharging, as concluded from the photo‐ESR and pulsed ESR experiments. In these experiments light sensitive ESR signals of Co2+ and shallow donor are observed. Their response to light favors cobalt 2+ to 3+ photoionization.
Strong and Conductive Dry Carbon Nanotube Films by Microcombing
Authors: Zhang Liwen , Wang Xin , Xu Weizong , Zhang Yongyi , Li Qingwen , Bradford Philip D. , Zhu Yuntian
Published: May 2015

In order to maximize the carbon nanotube (CNT) buckypaper properties, it is critical to improve their alignment and reduce their waviness. In this paper, a novel approach, microcombing, is reported to fabricate aligned CNT films with a uniform structure. High level of nanotube alignment and straightness was achieved using sharp surgical blades with microsized features at the blade edges to comb single layer of CNT sheet. These microcombs also reduced structural defects within the film and enhanced the nanotube packing density. Following the microcombing approach, the as‐produced CNT films demonstrated a tensile strength of up to 3.2 GPa, Young's modulus of up to 172 GPa, and electrical conductivity of up to 1.8 × 105 S m−1, which are much superior to previously reported CNT films or buckypapers. More importantly, this novel technique requires less rigorous process control and can construct CNT films with reproducible properties.
Designing a digital teaching resource to explain phases of the moon: A case study of preservice elementary teachers making a slowmation
Authors: Nielsen Wendy , Hoban Garry
Published: May 2015

This research studied a group of three preservice elementary teachers creating a narrated stop‐motion animation (Slowmation) from start to finish in 3 hours to explain the challenging concept of “phases of the moon” to elementary school children. The research questions investigated the preservice teachers' learning before and after the construction as well as how the preservice teachers designed the slowmation as a teaching resource. Data collection involved individual interviews immediately before and after the construction in conjunction with analysis of video and audio data collected during the construction process. Before the animation construction, the participants had little understanding of the causes of moon phases and one held an alternative conception. After creating the slowmation all three preservice teachers demonstrated more “elements” of the concept and appeared to resolve an alternative conception. There are two findings from this research: (i) creating a slowmation enabled the preservice teachers to develop more elements to contribute to their understanding of moon phases; (ii) the design of the slowmation was based on breaking the concept into a sequence of sub‐concepts that were represented digitally. Designing a digital teaching resource such as a slowmation to explain a concept involves preservice teachers breaking a concept down into coherent parts or “chunks” and representing the concept in multiple ways. This can be done within a science method class and is also a good way for the them to negotiate meanings about a difficult concept. © 2015 Wiley Periodicals, Inc. J Res Sci Teach 52: 1207–1233, 2015.
Preservice elementary teachers' emotional connections and disconnections to climate change in a science course
Authors: Hufnagel Elizabeth
Published: May 2015

Due to emotions' evaluative nature, they provide a lens for understanding personal and urgent engagement with events and experiences. Grounding this work in ethnography and sociolinguistics, I utilized discourse analysis to study the emotions of 30 preservice elementary teachers expressed about climate change in a science course. I describe the emotional connections and disconnections within and across the three aspects of climate change that students engaged with most deeply: the impacts, lack of action, and causes of climate change. These emotional connections and disconnections provide new ways to understand preservice elementary teachers' emotional sense‐making of this scientific issue. Implications for examining features of emotions to make salient emotional sense‐making of climate change are discussed. This emotional engagement differs from other findings in which people typically distance themselves from climate change. In addition, the value of analyzing all emotional expressions (“positive” and “negative”) in science learning settings is explained. © 2015 Wiley Periodicals, Inc. J Res Sci Teach 52: 1296–1324, 2015.
Interacting with a suite of educative features: Elementary science teachers' use of educative curriculum materials
Authors: Arias Anna Maria , Bismack Amber Schultz , Davis Elizabeth A. , Palincsar Annemarie Sullivan
Published: May 2015

New reform documents underscore the importance of learning both the practices and content of science. This integration of practices and content requires sophisticated teaching that does not often happen in elementary classrooms. Educative curriculum materials—materials explicitly designed to support teacher and student learning—have been posited as a way to support teachers to achieve these ambitious goals, yet little is known about how elementary teachers actually use educative curriculum materials in their interactions with students. To address this gap, we used qualitative case study methods drawing mainly on videorecords of the enactments of lessons and teacher interviews to investigate how two fourth‐grade teachers enacted a curriculum unit enhanced with educative features. Evidence of language and teaching moves promoted by the educative features was observed in the teachers' enactments. Findings suggest that variation existed in the teacher–curriculum interactions within and across teachers and across the suite of educative features. The teachers drew on educative features that contained representations of teacher and student work to envision possibilities for teaching the lesson while they used other features for identifying main ideas for the lesson. Implications for curriculum developers and teacher educators are discussed based on the patterns found in the teachers' use of the educative curriculum materials. © 2015 Wiley Periodicals, Inc. J Res Sci Teach 53: 422–449, 2016
Between Tradition and Modernity: Marriage Dynamics in Kyrgyzstan
Authors: Nedoluzhko Lesia , Agadjanian Victor
Published: May 2015

The demographic literature on union formation in post-communist Europe typically documents retreat from marriage and increase in cohabitation. However, sociological and anthropological studies of post-Soviet Central Asia often point to a resurgence of various traditional norms and practices, including those surrounding marriage, that were suppressed under Soviet rule. We engage these two perspectives on union formation by analyzing transition to first marriage in Kyrgyzstan both before and after the collapse of the USSR. We use uniquely detailed marriage histories from a nationally representative survey conducted in the period 2011–2012 to examine the dynamics of traditional marital practices among that country’s two main ethnic groups—Kyrgyz and Uzbeks—focusing on trends in arranged marriages and in marriages involving bride kidnapping. The analysis reveals instructive ethnic and period differences but also indicates an overall decline in the risks of both types of traditional marriage practices in the post-Soviet era. In fact, although the decline has characterized all marriage types, it was more substantial for traditional marriages. We interpret these trends as evidence of continuing modernization of nuptiality behavior in the region.
Multimodal prediction of conversion to Alzheimer's disease based on incomplete biomarkers∗
Authors: Ritter Kerstin , Schumacher Julia , Weygandt Martin , Buchert Ralph , Allefeld Carsten , Haynes John‐Dylan ,   Alzheimer's Disease Neuroimaging Initiative
Published: May 2015

Background

This study investigates the prediction of mild cognitive impairment‐to‐Alzheimer's disease (MCI‐to‐AD) conversion based on extensive multimodal data with varying degrees of missing values.

Methods

Based on Alzheimer's Disease Neuroimaging Initiative data from MCI‐patients including all available modalities, we predicted the conversion to AD within 3 years. Different ways of replacing missing data in combination with different classification algorithms are compared. The performance was evaluated on features prioritized by experts and automatically selected features.

Results

The conversion to AD could be predicted with a maximal accuracy of 73% using support vector machines and features chosen by experts. Among data modalities, neuropsychological, magnetic resonance imaging, and positron emission tomography data were most informative. The best single feature was the functional activities questionnaire.

Conclusion

Extensive multimodal and incomplete data can be adequately handled by a combination of missing data substitution, feature selection, and classification.
Post-crisis Belarus: Marxism and the lender of last resort
Authors: Bell Heather , Bell Robin
Published: May 2015

Existing literature has examined the predictions and proscriptions of Karl Marx in response to the 2008 global financial crisis. However, the suggestions put forth by the Marxist-leaning literature never took hold and state-level banking and finance policies have remained largely unchanged. While many criticisms of Marxism exist, this paper examines Belarus, a ‘neo-communist’ or ‘market-socialist’ state, to provide a new perspective on the continuation of capitalism in the United States and Europe. In the case of Belarus, the International Monetary Fund and the Eurasian Economic Community's Anti-Crisis Fund provided both the critical liquidity needed to temporarily quell the effects of the financial crisis. Their demands meant that Belarus agreed to speed its move away from the Soviet-era finance and banking policies and more towards its western capitalist neighbors. Its failure to implement these policies further hurt its recovery. Examining Belarus’ path to and out of its financial crisis makes apparent that the role of the international lender of last resort (LOLR). The LOLR acts as a key element in protecting states embroiled in the financial crisis from facing the possibility of making the difficult policy changes put forth by the Marxist literature. By ignoring its promises under the loan conditions from its LOLRs, Belarus moved further from the recovery promised by the Marxist suggestions.
Differential regulation of Connexin50 and Connexin46 by PI3K signaling
Authors: Martinez Jennifer M. , Wang Hong-Zhan , Lin Richard Z. , Brink Peter R. , White Thomas W.
Published: May 2015

Gap junction channels can modify their activity in response to cell signaling pathways. Here, we demonstrate that Connexin50 (Cx50) coupling, but not Connexin46 (Cx46), increased when co‐expressed with a constitutively active p110α subunit of PI3K in Xenopus oocytes. In addition, inhibition of PI3K signaling by blocking p110α, or Akt, significantly decreased gap junctional conductance in Cx50 transfected HeLa cells, with no effect on Cx46. Alterations in coupling levels were not a result of reduced Cx50 unitary conductance, suggesting that changes in the number of active channels were responsible. These data indicate that Cx50 is specifically regulated by the PI3K signaling pathway.
Biosensor‐based affinities and binding kinetics of small molecule antagonists to the adenosine A2A receptor reconstituted in HDL like particles
Authors: Segala Elena , Errey James C. , Fiez-Vandal Cédric , Zhukov Andrei , Cooke Robert M.
Published: May 2015

The options for investigating solubilised G protein‐coupled receptors (GPCRs) by biophysical techniques have long been hampered by their instability. A thermostabilised adenosine A2A receptor expressed in insect cells, purified in detergent and reconstituted into high‐density lipoprotein (HDL) particles was immobilised onto a Surface Plasmon Resonance sensor chip. This allowed measurement of affinities and kinetics for A2A antagonists with affinities ranging from 50 pM to almost 2 μM. Compared with other formats, reproduction of affinities, and dissociation and association rate constants are good, reasonable and poor respectively, indicating stabilised receptors in HDL particles are useful for investigating specific aspects of GPCR‐ligand interactions.
Enhanced expression and phosphorylation of the MET oncoprotein by glioma‐specific PTPRZ1–MET fusions
Authors: Chen Hui-Min , Yu Kai , Tang Xiao-yan , Bao Zhao-shi , Jiang Tao , Fan Xiao-Long , Chen Xiao-Wei , Su Xiao-Dong
Published: May 2015

PTPRZ1–MET (ZM) proteins are a group of fusion proteins identified in human gliomas by high‐throughput transcriptome sequencing. ZM fusions are associated with poor prognosis in afflicted glioma patients and mediate oncogenic effects in assays. In this study, we show that ZM‐carrying patients have increased hepatocyte growth factor receptor (MET) mRNA expression levels induced by fusion with receptor‐type tyrosine‐protein phosphatase zeta (PTPRZ1). Furthermore, ZM fusions preserve fundamental properties of wild‐type MET with respect to processing and dimerization, and enhance phosphorylation in an hepatocyte growth factor (HGF)‐dependent and independent manner. Our findings suggest that ZM induces gliomas through elevated expression and phosphorylation of the MET oncoprotein.
Phosphomimicking within the transit peptide of pHCF136 leads to reduced photosystem II accumulation in vivo
Authors: Nickel Catharina , Soll Jürgen , Schwenkert Serena
Published: May 2015

Most chloroplast resident proteins are equipped with N‐terminal transit peptides to ensure targeting from the cytosol to the organelle. Import rates can be modulated by phosphorylation and 14‐3‐3 binding within the transit peptides. Using the phosphorylatable preprotein pHCF136, a photosystem II assembly factor, we investigated the function of preprotein phosphorylation in vivo by complementing the seedling lethal hcf136 mutant. HCF136 constructs containing mutations within the 14‐3‐3 binding site were generated, either abolishing or mimicking phosphorylation. Interestingly, phosphomimicking reduced the import rate and the hcf136 phenotype could only be partially rescued, as shown by hampered photosystem II complex accumulation, which was most prominently observed in cotyledons.
RSRC1 SUMOylation enhances SUMOylation and inhibits transcriptional activity of estrogen receptor β
Authors: Chen Lihan , Li Weini , Qiu Weiyi , Ren Wen , Li Qincao , Han Baiyu , Zhou Lei , Cheng Long , Zhang Hao , Ye Qinong
Published: May 2015

The transcription factor estrogen receptor β (ERβ) plays roles in the central nervous, endocrine, cardiovascular, and immune systems. ERβ can be SUMOylated. However, the underlying mechanism remains unclear. Here, we show that RSRC1/SRrp53 interacts with ERβ and SUMOylation of RSRC1 is required for regulation of PIAS1‐mediated ERβ SUMOylation. RSRC1 promotes ERβ SUMOylation through enhanced interaction between ERβ and PIAS1. RSRC1 represses ERβ transcriptional activity through regulation of ERβ SUMOylation. By establishing RSRC1 as a novel cofactor for SUMOylation, our data provide insight into regulation of ERβ SUMOylation and indicate that SUMOylation of one protein can regulate another protein SUMOylation.
Mechanisms of RNA loading into exosomes
Authors: Janas Teresa , Janas Maja M. , Sapoń Karolina , Janas Tadeusz
Published: May 2015

Upon fusion of multivesicular bodies (MVBs) with the plasma membrane, intraluminal vesicles (ILVs) are released into the extracellular space as exosomes. Since the lipid composition of the exosomal membrane resembles that of raft microdomains, the inward budding process involves the raft‐like region of the MVB limiting membrane. Although published research suggests that cellular RNAs may be selectively sorted into exosomes, the molecular mechanisms remain elusive. In this review, we suggest that there is a continuous interaction of cellular RNAs with the outer (cytoplasmic) surface of MVBs and that the selection for incorporation of these RNAs into ILVs is based on their affinity to the raft‐like region in the outer layer of the MVB membrane.
The synaptotagmin juxtamembrane domain is involved in neuroexocytosis
Authors: Caccin Paola , Scorzeto Michele , Damiano Nunzio , Marin Oriano , Megighian Aram , Montecucco Cesare
Published: May 2015

Synaptotagmin is a synaptic vesicle membrane protein which changes conformation upon Ca2+ binding and triggers the fast neuroexocytosis that takes place at synapses. We have synthesized a series of peptides corresponding to the sequence of the cytosolic juxtamembrane domain of synaptotagmin, which is highly conserved among different isoforms and animal species, with or without either a hexyl hydrophobic chain or the hexyl group plus a fluorescein moiety. We show that these peptides inhibit neurotransmitter release, that they localize on the presynaptic membrane of the motor axon terminal at the neuromuscular junction and that they bind monophosphoinositides in a Ca2+‐independent manner. Based on these findings, we propose that the juxtamembrane cytosolic domain of synaptotagmin binds the cytosolic layer of the presynaptic membrane at rest. This binding brings synaptic vesicles and plasma membrane in a very close apposition, favouring the formation of hemifusion intermediates that enable rapid vesicle fusion.