bluuebunny/crossref_metadata_2025 huggingface dataset:
Decreased surface sialic acid content is a sensitive indicator of muscle damage
Authors: Iwata Yuko , Suzuki Osamu , Wakabayashi Shigeo
Published: August 2012

Introduction: The glycosylation state of the muscle sarcolemma is crucial for membrane strength and is thereby linked to pathologic conditions. No markers currently exist with sufficient sensitivity to detect muscle damage in biopsy samples. We aimed to determine whether surface sialic acid content is a useful criterion for estimating muscle injury. Methods: Sialic acid content was measured by comparing the fluorescence intensity of muscle sections stained with 2 types of lectins. One binds specifically to nonsialylated sugars, and the other binds to both sialylated and nonsialylated sugars. Results: Sialic acid levels were markedly reduced (60–80%) in muscles from dystrophin‐defective mice, δ‐sarcoglycan–deficient hamsters, merosin‐deficient mice, and patients with muscular dystrophy, when compared with their healthy counterparts. Conclusions: Testing for a marked decrease in sialic acid levels, which is caused by the release of trace amounts of sialidase from damaged muscles, is a sensitive detection method for muscle injury and could be commonly utilized for various subtypes of muscular dystrophy. Muscle Nerve 47:372‐378, 2013
Association between occupational stress and risk of overactive bladder and other lower urinary tract symptoms: A cross‐sectional study of female nurses in China
Authors: Zhang Chunfang , Hai Ting , Yu Luping , Liu Shijun , Li Qing , Zhang Xiaowei , Xu Tao , Wang Xiaofeng
Published: August 2012

Aims

To evaluate the prevalence of overactive bladder (OAB) and other lower urinary tract symptoms (LUTS), and their association with occupational stress in female nurses in China.

Methods

From September 2010 to March 2011, 1,135 registered female nurses with one or more years of nursing experience, were cluster‐sampled. The participants completed questionnaires on LUTS‐related symptoms and Occupational Stress Inventory‐Revised (OSI‐R) tests. Multiple logistic regressions were performed to evaluate the independent impact of perceived occupational stress on OAB and other LUTS, adjusting for age, body mass index (BMI), and history of childbearing and pelvic surgery.

Results

1,070 valid responses to questionnaires were obtained. The prevalence of OAB was 27.57% (95% CI: 24.89–30.25%). LUTS of any types occured in 89.63% of nurses, with 64.39% reporting urgency, 27.10% reporting increased daytime frequency, 17.88% reporting nocturia and 21.03% reporting urge incontinence. The occupational stress and psychological strain levels of nurses were higher than those of normative populations, while their coping resources were lower. Most of the sub‐scales of occupational stress and psychological strain showed higher results for nurses with OAB than for those OAB‐free, while coping resources were not found to make any statistically significant differences. After adjusting age, BMI, and childbearing and pelvic surgery history, each sub‐scale of OSI‐R was found to be associated with at least one type of LUTS.

Conclusions

The prevalence of OAB and other LUTS is high among female nurses in China, and occupational stress may be a contributing factor. Neurourol. Urodynam. 32: 254–260, 2013. © 2012 Wiley Periodicals, Inc.
Economic lot sizing with constant capacities and concave inventory costs
Authors: Ou Jinwen
Published: August 2012

This article studies the classical single‐item economic lot‐sizing problem with constant capacities, fixed‐plus‐linear order costs, and concave inventory costs, where backlogging is allowed. We propose an O(T3) optimal algorithm for the problem, which improves upon the O(T4) running time of the famous algorithm developed by Florian and Klein (Manage Sci18 (1971) 12–20). Instead of using the standard dynamic programming approach by predetermining the minimal cost for every possible subplan, we develop a backward dynamic programming algorithm to obtain a more efficient implementation. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012
Kana Tamata or Feasts of Men: An Interdisciplinary Approach for Identifying Cannibalism in Prehistoric Fiji
Authors: Jones S. , Walsh‐Haney H. , Quinn R.
Published: August 2012

By integrating osteological, taphonomic, archaeological and stable isotopic data, we test for cannibalism in the Lau Group, Fiji and discuss the potential underlying cause(s) and context(s) of this behaviour. First, we compare taphonomic and element representations of human skeletal material from two contexts in Fiji, examining human bone fragments from archaeological sites, including middens and burials in the Lau Island Group. Fourteen sites produced human remains. Only two of those sites included distinct human burial contexts, but in the remaining 12 sites, the human bone was recovered from middens or contexts where midden was mixed with possible secondary burials. A total of 262 number of identified specimens per species, representing an estimated 15 minimum number of individuals make up the Lau human assemblage. Second, we analysed bones contained in 20 individual human burials from four different sites that are housed at the Fiji Museum for comparative purposes. Third, we examine previously published stable isotopic (δ13C, δ15N) analysis of bone collagen to gauge protein consumption of likely cannibalised humans in midden contexts and potential cannibals from primary burials. We model a cannibalistic diet category within the context of isotopically measured Pacific Islands food groups and apply an isotopic mixing model to gauge plausible dietary contributions from six sources including human flesh. Isotopic mixing models of the Lauan samples illustrate a high diversity in reconstructed diets. The percent contribution of human flesh is low for all individual Lauans. We conclude that mortuary rituals evidenced by sharp‐force trauma may suggest non‐nutritive and non‐violent practices that may have included the consumption of small amounts of human flesh. Copyright © 2012 John Wiley & Sons, Ltd.
Laser processing of TiO2 films for dye solar cells: a thermal, sintering, throughput and embodied energy investigation
Authors: Mincuzzi G. , Schulz‐Ruhtenberg M. , Vesce L. , Reale A. , Di Carlo A. , Gillner A. , Brown T. M.
Published: August 2012

We have analysed and optimised a laser process for the sintering of the TiO2 layers in dye solar cells (DSCs). Through a thermographic characterisation of the process, we show that it is possible to scale and process large areas uniformly (16 cm2). We fabricated DSCs with nanocrystalline (nc)‐TiO2 films sintered by using pulsed ultraviolet laser with an average output power P varying from 1 W to 7 W whilst mainting a constant power conversion efficiency η. The highest efficiency reached for a laser sintered DSC was 7%. The time required to sinter 1 m2 of nc‐TiO2 film was found to decrease hyperbolically with P, which is important for determining process takt times. We quantified the embodied energy (EE) required to sinter 1 m2 of the active TiO2 layer for a variety of different processes, and found that the EE for the laser sintering process with a system wall plug efficiency of 3.5% to be competitive with the more conventional oven and belt furnace treatments. We outline the main features required from a laser system to carry out an efficient, energetically favourable and industrially applicable automated process with competitive throughput. Copyright © 2012 John Wiley & Sons, Ltd.
Organic solvent‐free catalytic hydrogenation of diene‐based polymer nanoparticles in latex form. Part II. Kinetic analysis and mechanistic study
Authors: Wang Hui , Yang Lijuan , Scott Stephen , Pan Qinmin , Rempel Garry L.
Published: August 2012

The central challenge that has limited the development of catalytic hydrogenation of diene‐based polymer latex (i.e., latex hydrogenation) in large‐scale production pertains to how to accomplish the optimal interplay of accelerating the hydrogenation rate, decreasing the required quantity of catalyst, and eliminating the need for an organic solvent. Here, we attempt to overcome this dilemma through decreasing the dimensions of the polymer substrate (such as below 20 nm) used in the hydrogenation process. Very small diene‐based polymer nanoparticles were synthesized and then used as the substrates for the subsequent latex hydrogenation. The effects of particle size, temperature, and catalyst concentration on the hydrogenation rate were fully investigated. An apparent first‐order kinetic model was proposed to describe the rate of hydrogen uptake with respect to the concentration of the olefinic substrate (CC). Mass transfer of both the hydrogen and catalyst involved in this solid (polymer)–liquid (water)–gas (hydrogen) three‐phase latex system is discussed. The competitive coordination of the catalyst between the CC and acrylonitrile units within the copolymer was elucidated. It was found that (1) using very small diene‐based polymer nanoparticles as the substrate, the hydrogenation rate of polymer latex can be increased vastly to achieve a high conversion of 95% while a quite low level of catalyst loading is required; (2) this latex hydrogenation process was completely free of organic solvent and no cross‐linking was found; (3) the mass transfer of hydrogen is not a rate‐determining step in the present hydrogenation reactions; (4) the catalyst was dispersed homogeneously within the polymer nanoparticles; (5) for the reaction that has reached about 95 mol % conversion, the kinetic study shows that the reaction is chemically controlled with an apparent activation energy of 100–110 kJ/mol; (6) the strong coordination of C[tbond]N to the catalytically active species RhH2Cl(PPh3)2 imposed a negative effect on the hydrogenation activity. The present research provides a comprehensive study to appreciate the underlying chemistry of latex hydrogenation of diene‐based polymer nanoparticles and more importantly shows great promise toward the commercialization of a “green” catalytic hydrogenation operation of a diene‐based polymer latex in industry. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Synthesis of nitroxide‐containing block copolymers for the formation of organic cathodes
Authors: Hauffman Guillaume , Rolland Julien , Bourgeois Jean‐Pierre , Vlad Alexandru , Gohy Jean‐François
Published: August 2012

This contribution describes the polymerization of 2,2,6,6‐tetramethylpiperidin‐4‐yl methacrylate by atom transfer radical polymerization (ATRP). Different catalytic systems are compared. The CuCl/4,4′‐dinonyl‐2,2′‐dipyridyl catalytic system allows a good control over the polymerization and provides polymers with a polydispersity index below 1.2. The successful polymerization of styrene from PTMPM‐Cl macroinitiators by ATRP is then demonstrated. Successful quantitative oxidation of PTMPM‐b‐PS block copolymers leads to poly(2,2,6,6‐tetramethylpiperidinyloxy‐4‐yl‐methacrylate)‐b‐poly(styrene) (PTMA‐b‐PS). The cyclic voltammogram of PTMA‐b‐PS indicates a reversible redox reaction at 3.6 V (vs. Li+/Li). Such block copolymers open new opportunities for the formation of functional organic cathode materials. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Tuning photovoltaic performance of 9,9‐dioctylfluorene‐alt‐5,7‐bis(thiophen‐2‐yl)‐2,3‐biphenylthieno[3,4‐b]pyrazine copolymeric derivatives by attaching additional donor units in pendant phenyl ring
Authors: Li Jianmin , Deng Xianping , Zhang Zhiyong , Wang Yafei , Liu Yu , He Keqi , Huang Ying , Tao Qiang , Quan Lixia , Zhu Weiguo
Published: August 2012

A class of the 9,9‐dioctylfluorene‐alt‐5,7‐bis(thiophen‐2‐yl)‐2,3‐biphenylthieno [3,4‐b]pyrazine copolymeric derivatives (PFO‐3ThPz‐D) attaching additional donor (D) units in the pendant phenyl ring with a D‐A
D structure was synthesized and investigated, where the additional D unit is a substituent group of fluorene, carbazole, and triphenylamine (Tpa). Their photovoltaic properties were significantly tuned by these pending donor units. Among these copolymers, the PFO‐3ThPz‐Tpa exhibited the best photovoltaic properties in the bulk heterojunction polymeric solar cells (BHJ‐PSC). The maximum power conversion efficiency (PCE) of 2.09% and the highest circuit current density (Jsc) of 7.91 mA/cm2 were obtained in the cell using a blend of PFO‐3ThPz‐Tpa and PC60BM (1:3, w/w) as active layer, which are 2.5 and 1.8 times higher than those corresponding levels in the other cell using the parent PFO‐3ThPz‐Ph copolymer instead of PFO‐3ThPz‐Tpa as donor, respectively. While PC60BM was replaced by PC70BM, the PFO‐3ThPz‐Tpa‐based BHJ‐PSC exhibited better photovoltaic properties with PCE of 3.08% and Jsc of 10.3 mA/cm2. This work demonstrated that attaching donor units into the D‐A‐based copolymeric side‐chain is a simple and effective method to improve the photovoltaic properties for the resulting copolymers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Facile synthesis of ABCDE‐type H‐shaped quintopolymers by combination of ATRP, ROP, and click chemistry and their potential applications as drug carriers
Authors: Liu Huanhuan , Li Shixian , Zhang Meijing , Shao Wei , Zhao Youliang
Published: August 2012

A facile approach to synthesis of ABCDE‐type H‐shaped quintopolymer comprising polystyrene (PSt, C) main chain and poly(ethylene glycol) (PEG, A), poly(ε‐caprolactone) (PCL, B), poly(L‐lactide) (PLLA, D), and poly(acrylic acid) (PAA, E) side chains was described, and physicochemical properties and potential applications as drug carriers of copolymers obtained were investigated. Azide‐alkyne cycloaddition reaction and hydrolysis were used to synthesize well‐defined H‐shaped quintopolymer. Cytotoxicity studies revealed H‐shaped copolymer aggregates were nontoxic and biocompatible, and drug loading and release properties were affected by macromolecular architecture, chemical composition, and pH value. The release rate of doxorubicin from copolymer aggregates at pH 7.4 was decreased in the order PAA‐b‐PLLA > H‐shaped copolymer > PEG‐PCL‐PSt star, and the release kinetics at lower pH was faster. The H‐shaped copolymer aggregates have a potential as controlled delivery vehicles due to their excellent storage stability, satisfactory drug loading capacity, and pH‐sensitive release rate of doxorubicin. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Alternating copolymers of hexafluoroisobutylene with vinyl trifluoroacetate and vinyl pentafluorobenzoate
Authors: Mikes Frantisek , Teng Hongxiang , Koike Yasuhiro , Okamoto Yoshiyuki
Published: August 2012

Copolymerizations of hexafluoroisobutylene (HFIB) with vinyl pentafluorobenzoate (VPFB) and vinyl trifluoroacetate (VTFA) were carried out in bulk using perfluorodibenzoyl peroxide as the radical initiator. The copolymers obtained were characterized by proton and fluorine NMR spectroscopy. The monomer reactivity ratios in the polymerization of HFIB with VPFB were r1 (HFIB) = 0, r2 (VPFB) = 0.373, and r1r2 = 0. The results indicated that these copolymers have alternating structures. Similarly, the copolymers of HFIB and VTFA also showed alternating structures. The films of HFIB‐co‐VPFB were prepared by casting THF solution of polymers. Films obtained were flexible and transparent. The refractive indices of copolymers were 1.4549, 1.4490, and 1.4438 at 532, 633, and 839 nm, respectively. The average Tgs of HFIB‐co‐VTFA and HFIB‐co‐VPFB were 52 and 71 °C, respectively. From these results, the Tg of the hypothetical HFIB homopolymer is postulated to be in between 70 and 90 °C, which may be useful in the assessment of Tgs of HFIB copolymers with other vinyl monomers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Synthesis, structural characterization, and olefin polymerization behavior of vanadium(III) complexes bearing bidentate phenoxy‐phosphine ligands
Authors: Zhang Sen‐Wang , Lu Ling‐Pan , Li Bai‐Xiang , Li Yue‐Sheng
Published: August 2012

Vanadium(III) complexes bearing phenoxy‐phosphine ligands (2a–g) (2‐R1‐4‐R2‐6‐PPh2‐C6H2O)VCl2(THF)2 (2a: R1 = R2 = H; 2b: R1 = F, R2 = H; 2c: R1 = Ph, R2 = H; 2d: R1 = tBu, R2 = H; 2e: R1 = R2 = Me; 2f: R1 = R2 = tBu; 2g: R1 = R2 = CMe2Ph) were prepared from VCl3(THF)3 by treating with 1.0 equiv of the ligand in tetrahydrofuran (THF) in the presence of excess triethylamine (TEA). The reaction of VCl3(THF)3 with 2.0 equiv of the ligand in THF in the presence of excess TEA afforded vanadium(III) complexes bearing two phenoxy‐phosphine ligands (3c–f). These complexes were characterized by FTIR and mass spectrum as well as elemental analyses. Structures of 2f and 3c were further confirmed by X‐ray crystallographic analyses. Complexes 2a–g and 3c–f were employed as the catalysts for ethylene polymerization under various reaction conditions. On activation with Et2AlCl, these complexes exhibited high catalytic activities (up to 41.3 kg PE/mmolV·h·bar) even at high temperature (70°C), and produced high molecular weight polymer with unimodal molecular weight distributions, indicating the polymerization took place in a single‐site nature. Complexes 3c–f displayed better thermal stability than the corresponding complexes 2a–g under similar conditions. In addition, copolymerizations of ethylene and 1‐hexene with precatalysts 2a–g were also explored in the presence of Et2AlCl. Catalytic activity, comonomer incorporation, and properties of the resultant polymers can be controlled over a wide range by tuning catalyst structures and reaction parameters.© 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Single‐pulse pulsed laser polymerization–electron paramagnetic resonance investigations into the termination kinetics of n‐butyl acrylate macromonomers
Authors: Barth Johannes , Buback Michael , Barner‐Kowollik Christopher , Junkers Tanja , Russell Gregory T.
Published: August 2012

The termination of model mid‐chain radicals (MCRs), which mimic radicals that occur in acrylate polymerization over a broad range of reaction conditions, has been studied by single‐pulse pulsed laser polymerization (SP‐PLP) in conjunction with electron paramagnetic resonance spectroscopy. The model radicals were generated by initiator‐fragment addition to acrylic macromonomers that were preformed prior to the kinetic experiments, thus enabling separation of termination from the propagation reaction, for these model radicals propagate sparingly, if at all, on the timescale of SP‐PLP experiments. Termination rate coefficients of the MCRs were determined in the temperature range of 0–60°C in acetonitrile and butyl propionate solution as well as in bulk macromonomer over the range of 0–100 °C. Termination rate coefficients slightly below those of the corresponding secondary radicals were deduced, demonstrating the relatively high termination activity of this species, even when undergoing MCR–MCR termination. For chain length of 10, a reduction by a factor of 6 is observed. Unusually high activation energies were found for the termination rate coefficient in these systems, with 35 kJ mol−1 being determined for bulk macromonomer. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Isomeric effect of sulfonated poly(arylene ether)s comprising dihydroxynaphthalene on properties for polymer electrolyte membranes
Authors: Sakaguchi Yoshimitsu , Kitamura Kota , Takase Satoshi
Published: August 2012

Polymer electrolyte membranes (PEMs) made of sulfonated poly(arylene ether)s consisted of 3,3′‐disulfo‐4,4′‐dichlorodiphenylsulfone disodium salt, 2,6‐dichlorobenzonitrile, and one of three dihydroxynaphthalene isomers (2,6‐, 2,7‐, and 1,5‐dihydroxynaphthalene, abbreviated as 2,6‐N, 2,7‐N, and 1,5‐N, respectively) were prepared with similar level of inherent viscosity and ion exchange capacity, and structural effect of the catenation in dihydroxynaphthalene isomers on membrane properties was compared. In the case of membranes for PEM fuel cell application with relatively high ion exchange capacity around 2.1 mequiv/g, three copolymers showed almost the same proton conductivity; however, swelling in water increased with the following order: 1,5‐N < 2,6‐N < 2,7N. In the case of direct methanol fuel cell membranes with lower ion exchange capacity around 1.5 mequiv/g, no remarkable difference in proton conductivity was also observed in three isomeric copolymers and swelling property and methanol permeability were lower in 1,5‐N and 2,6‐N copolymers than 2,7‐N copolymer. These tendencies show that higher rigidity or energy barrier for conformational change of polymer chain gives better performance of PEM for fuel cells with superior dimensional stability. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Synthesis of networked polymer based on ring‐opening addition reaction of 1,3‐benzoxazine with resorcinol
Authors: Oie Hiroaki , Mori Atsushi , Sudo Atsushi , Endo Takeshi
Published: August 2012

A highly efficient ring‐opening addition reaction of benzoxazine at ambient temperature has been developed with 2‐methylresorcinol as a nucleophilic reagent. In this reaction, 2‐methylresorcinol reacted with two equivalent amount of benzoxazine to give the corresponding 1:2 adduct, demonstrating its potential as a bifunctional nucleophile. Based on this reaction, a new crosslinking system consisting of a polymer bearing benzoxazine moieties in the side chains and 2‐methylresorcinol as a crosslinker has been performed to obtain the corresponding networked polymer. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Synthesis of stable aqueous dispersion of graphene/polyaniline composite mediated by polystyrene sulfonic acid
Authors: Luo Jing , Jiang Sisi , Wu Yong , Chen Meiling , Liu Xiaoya
Published: August 2012

A facile method of producing stable aqueous dispersion of graphene/polyaniline (PANI) composite is described, which involves the in situ polymerization of aniline on the surface of graphene with the aid of polystyrene sulfonic acid (PSS). The prepared aqueous graphene/PANI composite dispersion was very stable and no aggregation or precipitation was observed for several weeks. The excellent aqueous dispersibility and stability of the graphene/PANI composite is attributed to the cooperative interactions of π stacking interaction between PSS, PANI, and the graphene basal planes, and the electrostatic repulsions between negatively charged PSS bound on graphene/PANI composite. Fourier transform‐infrared spectrometry (FTIR), ultraviolet‐visible spectra (UV–vis), and Raman spectra confirmed the interaction of PANI and graphene in the composite, which effectively delocalize the electrons. In addition, the composite showed three orders of magnitude of conductivity increase compared with pure PANI. This new approach is simple, fast, and straightforward, representing a significant improvement in the processing of graphene/PANI composites. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Stanford R. Ovshinsky Prize for Excellence in Amorphous Chalcogenides
Authors: Popescu Mihai
Published: August 2012

The short history of the Ovshinsky Prize conferred for Excellence in Amorphous Chalcogenides is presented.
Relation between photodarkening and photoexpansion in As2S3 glass
Authors: Tanaka Keiji
Published: August 2012

We study comparatively some characteristics of photodarkening and photoexpansion in chalcogenide glasses. In thicker samples, both grow more slowly, but the thickness variations are different. The feature can be understood with an idea that the two phenomena originate from a common atomic displacement, while the expansion in thick films suffers marked delays, due to viscous transfer of photogenerated internal stress to sample surfaces. Densities of the common atomic site are estimated at 0.5–1 at.%, the situation corresponding to single isolated (uncorrelated) centres in medium‐range structures, which provides the quasi‐stability of illuminated states. We also discuss relations between the darkening, the expansion (density reduction), and a refractive‐index increase.
Memories of a visiting scientist
Authors: Mytilineou Eugenia
Published: August 2012

Stan Ovshinsky, the man who practically started the field of amorphous semiconductors in the West, is 90 years old this year. He always keeps the enthusiasm of a teenager and the slim and tall figure of a cypress tree. Stan's personality actually reminds me of these characteristic trees of the Mediterranean landscape; with their narrow tall figures pointing towards the sky and popping out of any green background surrounding them. Stan feels and behaves as a young man; even at the age of 85, following his old dream for changing the world, he founded a new company. I first met Stan and Iris in 1977. Since then, I have spent several sabbatical leaves in Energy Conversion Devices (ECD), from 1984 to 2004. In the following, our scientific collaboration and the build up of a very deep and sincere friendship will be described.
Emerging topological insulating phase in GeSbTe compounds
Authors: Kim Jeongwoo , Jhi Seung‐Hoon
Published: August 2012

The electronic property of GeSbTe compounds is studied within the notion of their topological insulating phase. We show that these compounds, as pseudo‐binary alloys of GeTe and Sb2Te3, in their crystalline phase with well‐ordered layer stacking have imbedded surface‐like states originating from topological insulating Sb2Te3 at interfaces between GeTe and Sb2Te3 layers. We demonstrate that these conducting states can significantly affect the electrical conduction of the compounds and are sensitive to Ge migration. Using first‐principles methods, we show that the topological insulating phase of GeSbTe compounds can be manipulated by controlling the composition and/or layer thickness. It is found that the interaction between the surface‐like states intervened by insulating GeTe layers creates an inversion gap to turn the compounds into topological insulating phase. We anticipate that the topological insulating property of GeSbTe can provide new insight into understanding the underlying physics in structural transitions of the compounds and a perspective of utilizing phase change materials as spin‐control devices as well as non‐volatile memory devices.
Phase‐change processors, memristors and memflectors
Authors: Wright C. David , Wang Lei , Aziz Mustafa M. , Diosdado Jorge A. Vazquez , Ashwin Peter
Published: August 2012

Phase‐change materials exhibit some remarkable properties. They can be crystallized in picoseconds and amorphized in femtoseconds, but remain stable against spontaneous crystallization for many years. They exhibit huge differences in optical and electrical properties between the amorphous and crystalline phases. Such properties have led, over the last four decades, to the successful development of both optical and electrical non‐volatile phase‐change memories. However, such binary memories only ‘scratch the surface’ in terms the remarkable potential applications of phase‐change materials and devices, which extend to arithmetic, logical and bio‐inspired (or neuromorphic) processing. In this paper we introduce and explain some of this remarkable functionality inherent to phase‐change systems. Phase‐change device operating in accumulation mode. This provides the basic mechanism for providing arithmetic, logic and neuronal type processing.

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Short range order and Ag diffusion threshold in Agx(Ge0.25Se0.75)100−x glasses
Authors: Piarristeguy A. A. , Cuello G. J. , Fernández‐Martínez A. , Cristiglio V. , Johnson M. , Ribes M. , Pradel A.
Published: August 2012

A structural investigation of Agx(Ge0.25Se0.75)100 − x glasses with x = 5, 15, and 25 at.% has been carried out by neutron diffraction and ab initio molecular dynamics (AIMD) simulation. A structural model for the glasses has been proposed: the Ge(Se1/2)4 tetrahedra would remain the fundamental structural units in all samples. The introduction of Ag in the Ge0.25Se0.75 network would lead to a decrease in homopolar SeSe bonds and appearance of GeGe bonds. A strong evolution in the AgAg correlations upon introduction of Ag was observed with the AgAg correlation distances changing from 4.4 Å for the Ag‐poor glass to 3.0 Å for the Ag‐rich ones. Such information was used to discuss the evolution of conductivity with Ag content in these glasses.
Alloy solid solution strengthening of Mg alloys: Valence effect
Authors: Chen Kuiying , Boyle Kevin P.
Published: August 2012

Ab initio density functional theory (DFT) calculations were carried out to investigate alloy solid solution strengthening of hexagonal close packed (HCP) Mg. The binary solid solution Mg–X base alloys (X = Gd, Nd, Ce, Bi, In, and Sn) were examined to identify a possible valence effect on the solution strengthening in terms of electronic density of states (DOS) and electron localized function (ELF). An addition of rare earth (RE) elements Gd, Nd, and Ce in Mg results in a hybridization between the localized f electrons of RE elements and the p electrons of Mg. The hybridization is primarily responsible for the formation of covalent bonds between RE elements and Mg. This electronic structure was then validated by the calculated ELF, illustrating a distribution of localized electrons between Mg and RE atoms. This peculiar chemical bonding characteristic successfully explains the experimentally observed solid solution strengthening induced by Gd, Nd, and Ce additions. An addition of sp‐elements of Bi, In, and Sn in Mg, however, leads to the formation of typical ionic bonds, which are not capable of inducing solid solution strengthening in Mg alloys. A discussion was made on a possible relationship between the chemical bonds and solid solution strengthening in Mg alloys.
Retracted: Antiproliferative Efficacy of Hesperetin (Citrus Flavanoid) in 1,2‐Dimethylhydrazine‐Induced Colon Cancer
Authors: Aranganathan Selvaraj , Nalini Namasivayam
Published: August 2012

Cancer is the second leading cause of death worldwide and is increasing at an alarming rate. The present study was to evaluate the antiproliferative effcts of hesperetin, a flavonoid commonly found in many herbal medicines and foods, on aberrant crypt foci (ACF), argyrophylic nucleolar organizer regions (AgNORs) and proliferating cell nuclear antigen (PCNA) in 1,2‐dimethylhydrazine (DMH)‐induced colon carcinogenesis in rats. Rats were given subcutaneous injections of DMH (20 mg/kg body weight) weekly for 15 weeks to induce carcinogenesis, and hesperetin was administered orally at the dose of 20 mg/kg body weight. DMH exposure alone produced a high incidence of ACF and showed positive staining for PCNA and AgNORs in colonic tissues. Supplementation with hesperetin lowered the PCNA labeling index and suppressed the formation of ACF in the rats with colon cancer. These results clearly reveal that dietary hesperetin possesses antiproliferative ability against chemically induced colon tumourigenesis. Copyright © 2012 John Wiley & Sons, Ltd.
Testing for white noise against locally stationary alternatives
Authors: Goerg Georg M.
Published: August 2012

Many real‐world systems have dynamics that evolve over time, yet stationary models still remain a popular choice in empirical time series studies. In this work, I show that one reason for seemingly correct stationary fits is a very low power of classic white noise tests against locally varying dynamics. In particular, if autocorrelations change over time but on average equal zero, standard white noise tests cannot detect this deviation from the null hypothesis due to their fundamental design. Here I introduce a moving‐window version of the Ljung–Box statistic with an asymptotic\documentclass{article}\usepackage{amsmath}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{amsfonts}\pagestyle{empty}\begin{document}$\chi^{2}$ \end{document}distribution under the null and much larger power facing processes with time‐varying autocorrelations. Simulations and a case study of tree‐ring data demonstrate the importance of the new test for applied time series studies. © 2012 Wiley Periodicals, Inc. Statistical Analysis and Data Mining, 2012
Screening as an application of decision theory
Authors: Longford Nicholas T.
Published: August 2012

We develop a decision‐theoretical approach to setting the threshold for a screening procedure that declares each examined subject as a positive or a negative. It is fundamentally different from maximising the Youden index. The method incorporates the consequences of the two kinds of bad decisions (false positives and false negatives) by means of a set of plausible loss functions elicited from a subject‐matter expert or committee. We present details for several classes of loss functions and within‐group distributions of the outcomes. We outline extensions related to mixture distributions and compositions of loss functions. We illustrate the method on simulated examples and apply it to real datasets. Copyright © 2012 John Wiley & Sons, Ltd.
Time trends and forecasts of body mass index from repeated cross‐sectional data: a different approach
Authors: Majer Istvan M. , Mackenbach Johan P. , van Baal Pieter H.M.
Published: August 2012

In this paper, we report a case study on a technical generalization of the Lee–Carter model, originally developed to project mortality, to forecast body mass index (BMI, kg/m 2). We present the method on an annually repeated cross‐sectional data set, the Dutch Health Survey, covering years between 1981 and 2008. We applied generalized additive models for location, scale and shape semi‐parametric regression models to estimate the probability distribution of BMI for each combination of age, gender and year assuming that BMI follows a Box–Cox power exponential distribution. We modelled and extrapolated the distribution parameters as a function of age and calendar time using the Lee–Carter model. The projected parameters defined future BMI distributions from which we derived the prevalence of normal weight, overweight and obesity. Our analysis showed that important changes occurred not only in the location and scale of the BMI distribution but also in the shape of it. The BMI distribution became flatter and more shifted to the right. Assuming that past trends in the distribution of BMI will continue in the future, we predicted a stable or slow increase in the prevalence of overweight until 2020 among men and women. We conclude that our adaptation of the Lee–Carter model provides an insightful and flexible way of forecasting BMI and that ignoring changes in the shape of the BMI distribution would likely result in biased forecasts. Copyright © 2012 John Wiley & Sons, Ltd.
The evaluation of biosimilarity index based on reproducibility probability for assessing follow‐on biologics
Authors: Hsieh Tsung‐Cheng , Chow Shein‐Chung , Yang Lan‐Yan , Chi Eric
Published: August 2012

Unlike small molecule drug products, biological products are therapeutic agents producted using of a living system or organism. Thus, the development of biologic products is a very different and complicated process that is sensitive to environmental factors such as light and temperature. Therefore, the therapeutic effect of follow‐on biologic products may not be equivalent to the innovative products even though the average biosimilarity has been established. Thus, Chow et al. suggested that the assessment of biosimilarity between biologic products should be conducted on the basis of variability in 2010. In this article, we propose a biosimilar index that is derived on the basis of estimated reproducibility probability approach and Bayesian approach, respectively. We conducted simulation studies to empirically investigate the relationship of reproducibility probability under various parameter combinations. The simulation results demonstrate that the proposed method based on biosimilar index can reflect the characteristics and impact of variability on the therapeutic effect of biologic products. Copyright © 2012 John Wiley & Sons, Ltd.
Decoupling market incumbency from organizational prehistory: Locating the real sources of competitive advantage in R&D for radical innovation
Authors: Lourdes Sosa M.
Published: August 2012

The creative destruction literature has argued that differences in R&D performance of incumbent vs. entrant firms can be explained through organizational change theories about established vs. de novo firms. A disconnect exists between these theories and the available empirical evidence because often the best performing firms are established firms as well. I propose to resolve this disconnect by distinguishing between market incumbency (presence in a market prior to a discontinuity) and organizational prehistory (organizational experience prior to a transition, whether between technologies or between markets). Doing so allows me to contrast incumbent vs. entrant and de alio vs. de novo studies, and to suggest more robust future research designs. I illustrate my proposition using qualitative data from the anticancer and AIDS‐treatment drug markets. Copyright © 2012 John Wiley & Sons, Ltd.
Reverse engineering of gene regulatory networks from biological data
Authors: Liu Li‐Zhi , Wu Fang‐Xiang , Zhang Wen‐Jun
Published: August 2012

Reverse engineering of gene regulatory networks (GRNs) is one of the most challenging tasks in systems biology and bioinformatics. It aims at revealing network topologies and regulation relationships between components from biological data. Owing to the development of biotechnologies, various types of biological data are collected from experiments. With the availability of these data, many methods have been developed to infer GRNs. This paper firstly provides an introduction to the basic biological background and the general idea of GRN inferences. Then, different methods are surveyed from two aspects: models that those methods are based on and inference algorithms that those methods use. The advantages and disadvantages of these models and algorithms are discussed. © 2012 Wiley Periodicals, Inc.

This article is categorized under:

Algorithmic Development > Biological Data Mining
Flocculation of microfibrillated cellulose in shear flow
Authors: Karppinen Anni , Saarinen Tapio , Salmela Juha , Laukkanen Antti , Nuopponen Markus , Seppälä Jukka
Published: August 2012

In this work, the rheological properties of microfibrillated cellulose suspensions under stepped flow and constant shear were studied using a combination of rotational dynamic rheometer and digital imaging. During each rheological measurement, the structure of the suspension was monitored through a transparent outer cylinder with a digital camera. This enabled simultaneous analysis of the suspension floc size distribution and traditional rheological characterization. In stepped flow conditions, a good correlation between suspension floc structure and flow curve measurement was found. At constant shear, the suspension structure was dependent on the shear rate and concentration of the suspension. A low shear rate resulted in heterogeneous floc structure, which was also detected by an increase in the ratio of the viscous component to elastic component in the rheological measurement. At low concentrations and 0.5 s−1shear rate, flow induced a formation of floc cylinders between the rotating cylinder and stationary cup surface.
“Grasping the Grey”: Patient Understanding and Interpretation of an Intermediate Allele Predictive Test Result for Huntington Disease
Authors: Semaka A. , Balneaves L. G. , Hayden M. R.
Published: August 2012

Since the discovery of the genetic mutation underlying Huntington disease (HD) and the development of predictive testing, the genetics of HD has generally been described as straightforward; an individual receives either mutation‐positive or negative predictive test results. However, in actuality, the genetics of HD is complex and a small proportion of individuals receive an unusual predictive test result called an intermediate allele (IA). Unlike mutation‐positive or negative results, IAs confer uncertain clinical implications. While individuals with an IA will usually not develop HD, there remains an unknown risk for their children and future generations to develop the disorder. The purpose of this study was to explore how individuals understood and interpreted their IA result. Interviews were conducted with 29 individuals who received an IA result and 8 medical genetics service providers. Interviews were analyzed using the constant comparative method and the coding procedures of grounded theory. Many participants had difficulty “Grasping the Grey” (i.e. understanding and interpreting their IA results) and their family experience, beliefs, expectations, and genetic counseling influenced the degree of this struggle. The theoretical model developed informs clinical practice regarding IAs, ensuring that this unique subset of patients received appropriate education, support, and counseling.
Predicted Changes in Fatty Acid Intakes, Plasma Lipids, and Cardiovascular Disease Risk Following Replacement of trans Fatty Acid‐Containing Soybean Oil with Application‐Appropriate Alternatives
Authors: Lefevre Michael , Mensink Ronald P. , Kris‐Etherton Penny M. , Petersen Barbara , Smith Kim , Flickinger Brent D.
Published: August 2012

The varied functional requirements satisfied by trans fatty acid (TFA)—containing oils constrains the selection of alternative fats and oils for use as potential replacements in specific food applications. We aimed to model the effects of replacing TFA‐containing partially hydrogenated soybean oil (PHSBO) with application‐appropriate alternatives on population fatty acid intakes, plasma lipids, and cardiovascular disease (CVD) risk. Using the National Health and Nutrition Examination Survey 24‐hour dietary recalls for 1999–2002, we selected 25 food categories, accounting for 86 % of soybean oil (SBO) and 79 % of TFA intake for replacement modeling. Before modeling, those in the middle quintile had a mean PHSBO TFA intake of 1.2 % of energy. PHSBO replacement in applications requiring thermal stability by either low‐linolenic acid SBO or mid‐oleic, low‐linolenic acid SBO decreased TFA intake by 0.3 % of energy and predicted CVD risk by 0.7–0.8 %. PHSBO replacement in applications requiring functional properties with palm‐based oils reduced TFA intake by 0.8 % of energy, increased palmitic acid intake by 1.0 % of energy, and reduced predicted CVD risk by 0.4 %, whereas replacement with fully hydrogenated interesterified SBO reduced TFA intake by 0.7 % of energy, increased stearic acid intake by 1.0 % of energy, and decreased predicted CVD risk by 1.2 %. PHSBO replacement in both thermal and functional applications reduced TFA intake by 1.0 % of energy and predicted CVD risk by 1.5 %. Based solely on changes in plasma lipids and lipoproteins, all PHSBO replacement models reduced estimated CVD risk, albeit less than previously reported using simpler replacement models.
Aguaribay and Cedron Essential Oils as Natural Antioxidants in Oil‐Roasted and Salted Peanuts
Authors: Olmedo Rubén H. , Nepote Valeria , Grosso Nelson R.
Published: August 2012

The study objective was to evaluate the antioxidant effect of aguaribay and cedron essential oils on oil‐roasted and salted peanuts. Fried‐salted peanuts (FP), fried‐salted peanuts with addition of BHT (FP‐BHT) aguaribay (FP‐A) and cedron (FP‐C) essential oils were prepared. Peroxide (PV) and p‐anisidine (AV) values, conjugated dienes (CD) and sensory descriptive attributes were analyzed on the products during storage. The major compounds detected were 25.6 % spathulenol and 24.4 % geranial and 27.3 % neral in cedron essential oils and 12.7 % elemol, 11.7 % α‐pinene, 9.3 % β‐pinene, 8.3 % limonene and 8.2 % α‐phellandrene in aguaribay essential oil. PV, AV and CD were lower in FP‐BHT during storage. At storage day 112, PVs were 94.86, 82.74, 76.29, and 63.89 mequiv O2 kg−1 in FP, FP‐A, FP‐C and FP‐BHT, respectively. FP‐C and FP‐A had lipid oxidation values between FP and FP‐BHT. The intensity ratings of oxidized and cardboard flavors increased more in the control sample (FP) than the other samples. At storage day 112, FP‐A, FP‐BHT and FP‐C exhibited oxidized intensity ratings of 24.13, 24.9 and 26.1, respectively, lower than FP (35.83). Aguaribay and cedron essential oils showed protective effect against lipid oxidation in fried‐salted peanuts. However, these essential oils could affect the sensory profile and consumer acceptance of this product.
A Review of Undergraduate Evolution Education in U.S. Universities: Building a Unifying Framework
Authors: Lloyd-Strovas Jenny D. , Bernal Ximena E.
Published: August 2012

Despite a considerable amount of scientific evidence, evolution is still a highly controversial issue in American education. This review analyzes studies that investigate the relationship between evolution education, the nature of science, and religious beliefs in U.S. universities. We performed a comprehensive literature search focusing on publications that analyzed and compared at least two of the following constructs: understanding of evolutionary theory (ET), acceptance of ET, instruction in ET, prior exposure to ET, religious beliefs, understanding the nature of science, and understanding of scientific theories. Here, we examine publications for consistent relationships among constructs across studies and discuss the most commonly cited education strategies for teaching evolution in higher education. Based on the literature, we find that instruction has a significant and positive effect on acceptance and understanding of ET; acceptance and understanding, however, are not directly related. We also find that the relationship between acceptance of ET and religious beliefs is unclear and needs further research. Through reviewing 15 published studies, we find that the primary problems associated with undergraduate evolution education research are: small sample size, varying methodologies, lack of statistical analysis, inappropriate use of constructs, and lack of continuity among studies. This review exposes the need for a unifying framework and development of experts in this field to investigate and understand the factors that affect evolution education at U.S. universities.
Baulandpotenzialanalyse als Instrument zur Umsetzung nachhaltiger Siedlungsentwicklung – das Fallbeispiel Biosphärenpark Wienerwald
Authors: Musil Robert , Pindur Peter
Published: August 2012

This paper introduces a land suitability analysis, based on the Dutch “ABC location planning”. Two criteria are applied in this process: Firstly, the accessibility of high-ranking local public transport locations as well as town centres, and secondly, the density of the surrounding urban fabric. The aim of the paper is not only to employ this method as a technical assessment instrument for planners, but to use its transparency and traceability for the purpose of introducing a “mediation and communication tool” into discussion processes at the local level. The underlying case study involved the assessment of the building land reserves of Lower Austrian municipalities belonging to the Biosphere Reserve Wienerwald. These are characterised both by a significant degree of suburbanisation radiating from Vienna, the capital of Austria, and also by the considerable heterogeneity of the settlement structure. The method described not only serves to operationalize the process of sustainability within local spatial planning, but also to make planning processes accessible to larger groups of actors in terms of a governance strategy, thus triggering broader discussion processes at the local level, about when settlement development can be seen as “good” or “bad”.