bluuebunny/crossref_metadata_2025 huggingface dataset:
Centre for Applied Language Studies, University of Limerick, Ireland
Authors: Chambers Angela , Atkinson David , Farr Fiona
Published: March 2015

The Centre for Applied Language Studies (CALS), founded in 1997, brings together researchers and postgraduate students from several disciplines in language studies, and is structured in three research clusters: New learning environments; Discourse, society and identity; and Plurilingualism and language policy. There is a certain amount of overlapping between the clusters, and several researchers are active in more than one cluster. Thus research in language teacher education is present both in the New learning environments cluster and in Discourse, society and identity. Corpus-based methodologies are also prominent in both these clusters. Furthermore, discourse analysis is present as a methodology in all three. The following sections provide information on current research and selected research outcomes within the three research clusters from 2011 to 2013.
Determination of the initial conditions by solving boundary value problem method for period-one walking of a passive biped walking robots
Authors: Safartoobi Masoumeh , Dardel Morteza , Hassan Ghasemi Mohammad , Mohammadi Daniali Hamidreza
Published: March 2015

With regard to the small basin of attraction of the passive limit cycles, it is important to start from a proper initial condition for stable walking. The present study investigates the passive dynamic behaviors of two-dimensional bipedal walkers of a compass gait model with different foot shapes. In order to find proper initial conditions for stable and unstable period-one gait limit cycles, a method based on solving the nonlinear equations of motion is presented as a boundary value problem (BVP). An initial guess is required to solve the related BVP that is obtained by solving an initial value problem (IVP). For parametric analysis purposes, a continuation method is applied. Simulation results reveal two, period-one gait cycles and the effects of parameters variation for all models.
Analyzing Language Policy and Social Identification Across Heterogeneous Scales
Authors: Mortimer Katherine S. , Wortham Stanton
Published: March 2015

Attempts to improve education often change how language is used in schools. Many such efforts aim to include minoritized students by more fully including their languages. These are often met with resistance not so much about language but more about identity. Thus processes of social identification are implicated in efforts to change language in education. If we are to understand how identity and language policy interconnect, we must analyze how stability and change are produced in each. This requires attention to macro-level patterns and to micro-level practices. But a two-scale account—micro instantiation of macro categories and micro changes shaping macro structures—does not adequately explain identity and language policy. This article focuses on educational language policy implementation, how language use and social identification change in an evolving policy context. We argue that change and stability in language policy implementation must be explained with reference to heterogeneous resources from multiple timescales—beyond micro and macro—as these resources establish and change social identities. We review recent research using multiple timescales to understand social processes like identification and policy implementation, and we illustrate the use of such a scalar account to describe the social identification of one student in a sixth grade classroom in Paraguay in the midst of a major national educational language policy change. We show how a person's identification as a new kind of minority language speaker involved heterogeneous resources from various spatiotemporal scales. We argue that analysis of the heterogeneous resources involved in social identification is essential to understanding the role that these processes play in cultural, pedagogical, and language change.
Age Differences in Trade-off Decisions: Different Strategies but Similar Outcomes
Authors: Ma Xiaodong , Chen Yiwei
Published: March 2015

L'objectif principal de cette étude était d'examiner les différences conditionnées par l'âge dans le traitement des stratégies de décisions émotionnellement difficiles. En outre, l'étude a testé les contributions pertinentes des mécanismes cognitifs et émotionnels à des différences dans le traitement de ces stratégies conditionnées par l'âge. Quarante jeunes adultes et quarante adultes plus âgés, en tout, ont été assignés au hasard soit à un niveau élevé ou à un niveau bas de difficulté émotionnelle qu'implique la décision d'acheter une automobile. MouselabWEB logiciel a été utilisé pour tracer les stratégies de traitement des partici- pants. Les résultats ont montré que les personnes âgées étaient plus susceptibles d'utiliser des stratégies de traitement basées sur les attributs, tandis que les jeunes adultes étaient plus susceptibles d'utiliser des stratégies de traitement basées sur des solutions de rechange à l'état très émotive. D'autre part, les jeunes adultes et les adultes plus âgés ont préféré utiliser des stratégies de traitement fondées sur des alternatives dans des conditions d'émotion faible. De plus, les résultats suggèrent que la mesure cognitive (c'est à dire, programmation de chiffres-symboles) n'était pas corrélée avec les effets de l'âge sur les stratégies de traitement.
The challenges of treating women with recurrent urinary tract infections in primary care: a qualitative study of GPs’ experiences of conventional management and their attitudes towards possible herbal options
Authors: Flower Andrew , Winters David , Bishop Felicity L. , Lewith George
Published: March 2015

Aim

To explore GPs’ experiences of managing recurrent urinary tract infections (RUTIs) and their views on the use of herbal medicines for this condition.

Background

RUTIs are an important problem commonly managed in primary care. Antibiotic prophylaxis is an effective treatment for acute infections but growing microbial resistance, adverse effects, and the lack of sustained long-term benefits mean that novel treatments are required. There are a number of promising reports of herbal medicines being used to treat RUTIs.

Methods

A total of 15 GPs (seven female; aged 34–59 years; in practice from 3 to 31 years) were purposively sampled and took part in semi-structured face-to-face and telephone interviews. Interviews were digitally recorded, transcribed, and analysed using inductive thematic analysis. Data collection and analysis proceeded iteratively to allow emerging themes to inform subsequent interviews.

Findings

Participants were aware of the disabling effect of RUTIs on women’s lives. GPs experienced significant challenges in their management of RUTIs with decisions about the provision of antibiotics being particularly complex. While some participants were open to the possibility of herbal treatment options they required more research into effectiveness and safety, better regulation of herbal practitioners, and assurance about herbal quality control and potential herb–drug interactions.
Achtsamkeitsbasierte Therapieverfahren bei der Aufmerksamkeitsdefizit-/ Hyperaktivitätsstörung (ADHS)
Authors: Schmiedeler Sandra
Published: March 2015

Es wird ein Überblick über den aktuellen Forschungsstand zu achtsamkeitsbasierten Ansätzen in der Therapie der Aufmerksamkeitsdefizit- und Hyperaktivitätsstörung (ADHS) gegeben. Achtsamkeit kann als eine Form der Aufmerksamkeit verstanden werden, die durch eine Bewusstheit der momentanen Erlebensvorgänge charakterisiert ist und üblicherweise durch die Praxis der Meditation vermittelt wird. Die Literaturrecherche zeigt, dass Achtsamkeitstrainings mit einer Verbesserung von Aufmerksamkeitsprozessen und Selbstregulationsfähigkeiten zusammenhängen und damit solche Fähigkeiten fördern, mit denen ADHS-Betroffene Schwierigkeiten haben. Auch wenn bislang nur wenige Wirksamkeitsstudien von Achtsamkeitstrainings bei ADHS existieren und viele Untersuchungen methodische Mängel aufweisen, legen die ersten Ergebnisse nahe, dass achtsamkeitsbasierte Ansätze bei der ADHS-Therapie hilfreich sind.
Prognostic significance of Cbx4 expression and its beneficial effect for transarterial chemoembolization in hepatocellular carcinoma
Authors: Jiao H-K , Xu Y , Li J , Wang W , Mei Z , Long X-D , Chen G-Q
Published: March 2015

Our recent investigations showed that polycomb chromobox 4 (Cbx4) promotes angiogenesis and metastasis of hepatocellular carcinoma (HCC) through its sumoylating action on hypoxia-inducible factor-1α protein. Here, we attempt to identify the prognostic significances of Cbx4 by a retrospective analyses in 727 cases of HCC patients with and without postoperative transarterial chemoembolization (TACE) or transarterial embolization (TAE). Binary logistic regression tests indicated that Cbx4 is correlated with histological grading, tumor-node-metastasis stage, microvessel density, distant metastasis and hematogenous metastasis of HCC. By univariate and multivariate analyses, we show that Cbx4 is an independent prognostic factor of HCC, and both TAE and TACE treatments have no effects on the overall survival in HCC patients with low Cbx4 expression. More intriguingly, TACE prolongs, while TAE shortens, the overall survival of HCC patients with high Cbx4 expression, indicating that Cbx4 is a good biomarker on decision-making to perform postoperative TACE in HCC patients. Moreover, Cbx4 overexpression enhances while Cbx4 silencing antagonizes doxorubicin-induced cell death of HCC cell lines. In conclusion, Cbx4 is an independent prognostic factor for HCC patients, and the patients with high Cbx4 expression should receive postoperative TACE treatment to improve their survival.
Sub-nanosecond signal propagation in anisotropy-engineered nanomagnetic logic chains
Authors: Gu Zheng , Nowakowski Mark E. , Carlton David B. , Storz Ralph , Im Mi-Young , Hong Jeongmin , Chao Weilun , Lambson Brian , Bennett Patrick , Alam Mohmmad T. , Marcus Matthew A. , Doran Andrew , Young Anthony , Scholl Andreas , Fischer Peter , Bokor Jeffrey
Published: March 2015

Energy efficient nanomagnetic logic (NML) computing architectures propagate binary information by relying on dipolar field coupling to reorient closely spaced nanoscale magnets. Signal propagation in nanomagnet chains has been previously characterized by static magnetic imaging experiments; however, the mechanisms that determine the final state and their reproducibility over millions of cycles in high-speed operation have yet to be experimentally investigated. Here we present a study of NML operation in a high-speed regime. We perform direct imaging of digital signal propagation in permalloy nanomagnet chains with varying degrees of shape-engineered biaxial anisotropy using full-field magnetic X-ray transmission microscopy and time-resolved photoemission electron microscopy after applying nanosecond magnetic field pulses. An intrinsic switching time of 100 ps per magnet is observed. These experiments, and accompanying macrospin and micromagnetic simulations, reveal the underlying physics of NML architectures repetitively operated on nanosecond timescales and identify relevant engineering parameters to optimize performance and reliability.
Translational diffusion of hydration water correlates with functional motions in folded and intrinsically disordered proteins
Authors: Schirò Giorgio , Fichou Yann , Gallat Francois-Xavier , Wood Kathleen , Gabel Frank , Moulin Martine , Härtlein Michael , Heyden Matthias , Colletier Jacques-Philippe , Orecchini Andrea , Paciaroni Alessandro , Wuttke Joachim , Tobias Douglas J. , Weik Martin
Published: March 2015

Hydration water is the natural matrix of biological macromolecules and is essential for their activity in cells. The coupling between water and protein dynamics has been intensively studied, yet it remains controversial. Here we combine protein perdeuteration, neutron scattering and molecular dynamics simulations to explore the nature of hydration water motions at temperatures between 200 and 300 K, across the so-called protein dynamical transition, in the intrinsically disordered human protein tau and the globular maltose binding protein. Quasi-elastic broadening is fitted with a model of translating, rotating and immobile water molecules. In both experiment and simulation, the translational component markedly increases at the protein dynamical transition (around 240 K), regardless of whether the protein is intrinsically disordered or folded. Thus, we generalize the notion that the translational diffusion of water molecules on a protein surface promotes the large-amplitude motions of proteins that are required for their biological activity.
Highly porous non-precious bimetallic electrocatalysts for efficient hydrogen evolution
Authors: Lu Qi , Hutchings Gregory S. , Yu Weiting , Zhou Yang , Forest Robert V. , Tao Runzhe , Rosen Jonathan , Yonemoto Bryan T. , Cao Zeyuan , Zheng Haimei , Xiao John Q. , Jiao Feng , Chen Jingguang G.
Published: March 2015

A robust and efficient non-precious metal catalyst for hydrogen evolution reaction is one of the key components for carbon dioxide-free hydrogen production. Here we report that a hierarchical nanoporous copper-titanium bimetallic electrocatalyst is able to produce hydrogen from water under a mild overpotential at more than twice the rate of state-of-the-art carbon-supported platinum catalyst. Although both copper and titanium are known to be poor hydrogen evolution catalysts, the combination of these two elements creates unique copper-copper-titanium hollow sites, which have a hydrogen-binding energy very similar to that of platinum, resulting in an exceptional hydrogen evolution activity. In addition, the hierarchical porosity of the nanoporous copper-titanium catalyst also contributes to its high hydrogen evolution activity, because it provides a large-surface area for electrocatalytic hydrogen evolution, and improves the mass transport properties. Moreover, the catalyst is self-supported, eliminating the overpotential associated with the catalyst/support interface.
Coherent quantum depletion of an interacting atom condensate
Authors: Kira M.
Published: March 2015

Sufficiently strong interactions promote coherent quantum transitions in spite of thermalization and losses, which are the adversaries of delicate effects such as reversibility and correlations. In atomic Bose–Einstein condensates (BECs), strong atom–atom interactions can eject atoms from the BEC to the normal component, yielding quantum depletion instead of temperature depletion. A recent experiment has already been verified to overcome losses. Here I show that it also achieves coherent quantum-depletion dynamics in a BEC swept fast enough from weak to strong atom–atom interactions. The elementary coherent process first excites the normal component into a liquid state that evolves into a spherical shell state, where the atom occupation peaks at a finite momentum to shield 50% of the BEC atoms from annihilation. The identified coherent processes resemble ultrafast semiconductor excitations expanding the scope of BEC explorations to many-body non-equilibrium studies.
Hardy-Weinberg equilibrium revisited for inferences on genotypes featuring allele and copy-number variations
Authors: Recke Andreas , Recke Klaus-Günther , Ibrahim Saleh , Möller Steffen , Vonthein Reinhard
Published: March 2015

Copy number variations represent a substantial source of genetic variation and are associated with a plethora of physiological and pathophysiological conditions. Joint copy number and allelic variations (CNAVs) are difficult to analyze and require new strategies to unravel the properties of genotype distributions. We developed a Bayesian hidden Markov model (HMM) approach that allows dissecting intrinsic properties and metastructures of the distribution of CNAVs within populations, in particular haplotype phases of genes with varying copy numbers. As a key feature, this approach incorporates an extension of the Hardy-Weinberg equilibrium, allowing both a comprehensive and parsimonious model design. We demonstrate the quality of performance and applicability of the HMM approach with a real data set describing the Fcγ receptor (FcγR) gene region. Our concept, using a dynamic process to analyze a static distribution, establishes the basis for a novel understanding of complex genomic data sets.
Biosynthesis of soluble carotenoid holoproteins in Escherichia coli
Authors: de Carbon Céline Bourcier , Thurotte Adrien , Wilson Adjélé , Perreau François , Kirilovsky Diana
Published: March 2015

Carotenoids are widely distributed natural pigments that are excellent antioxidants acting in photoprotection. They are typically solubilized in membranes or attached to proteins. In cyanobacteria, the photoactive soluble Orange Carotenoid Protein (OCP) is involved in photoprotective mechanisms as a highly active singlet oxygen and excitation energy quencher. Here we describe a method for producing large amounts of holo-OCP in E.coli. The six different genes involved in the synthesis of holo-OCP were introduced into E. coli using three different plasmids. The choice of promoters and the order of gene induction were important: the induction of genes involved in carotenoid synthesis must precede the induction of the ocp gene in order to obtain holo-OCPs. Active holo-OCPs with primary structures derived from several cyanobacterial strains and containing different carotenoids were isolated. This approach for rapid heterologous synthesis of large quantities of carotenoproteins is a fundamental advance in the production of antioxidants of great interest to the pharmaceutical and cosmetic industries.
A new model of tethered cord syndrome produced by slow traction
Authors: Huang Sheng-Li , Peng Jun , Yuan Guo-Lian , Ding Xiao-Yan , He Xi-Jing , Lan Bin-Shang
Published: March 2015

The development of a suitable animal model is important for clarifying the pathogenesis of tethered cord syndrome (TCS). This study was undertaken to develop a new animal model for investigating the pathogenesis and therapeutic strategies for TCS. A traction device, a filum terminale tractor, was designed exclusively for this experiment. A TCS model was produced in cats using the tractor to fixate the filum terminale to the dorsal aspect of the second sacrum. The responses to tethering were evaluated by electron microscopy and electromyography for detection of somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) at designated time points. Progressive swaying gait and lameness in clinical performance were observed with cord traction. Histopathological examination revealed an association between the increasing traction in the spinal cord and the increase in impaired nerve cells. No changes of SEPs and MEPs were detected in the untethered cats, while the latencies of SEPs and MEPs significantly increased in the tethered cats. The TCS model established in this study is simple and reproducible, in which varying degrees of tension could be applied to the neural elements.
Late-responding normal tissue cells benefit from high-precision radiotherapy with prolonged fraction delivery times via enhanced autophagy
Authors: Yao Qiwei , Zheng Rong , Xie Guozhu , Liao Guixiang , Du Shasha , Ren Chen , Li Rong , Lin Xiaoshan , Hu Daokun , Yuan Yawei
Published: March 2015

High-precision radiotherapy (HPR) has established its important role in the treatment of tumors due to its precise dose distribution. Given its more complicated delivery process, HPR commonly requires more fraction delivery time (FDT). However, it is unknown whether it has an identical response of prolonged FDT on different normal tissues. Our results showed that fractionated irradiation with prolonged FDTs (15, 36 and 50 minutes) enhanced cell surviving fractions for normal tissue cells compared with irradiation with an FDT of 2 minutes. However, the late-responding normal cell line HEI-OC1 was more responsive to prolonged FDTs and demonstrated higher surviving fractions and significantly decreased apoptosis and DNA damage compared to the acute-responding normal cell line HaCaT. Increased autophagy mediated via the ATM-AMPK pathway was observed in HEI-OC1 cells compared with HaCaT cells when irradiated with prolonged FDTs. Furthermore, treatment with the autophagy inhibitor 3-MA or ATM inhibitor KU55933 resulted in enhanced ROS accumulation and attenuation of the effect of prolonged FDT-mediated protection on irradiated HEI-OC1 cells. Our results indicated that late-responding normal tissue cells benefitted more from prolonged FDTs compared with acute-responding tissue cells, which was mainly attributed to enhanced cytoprotective autophagy mediated via the ATM/AMPK signaling pathway.
Plasmon-Assisted Audio Recording
Authors: Chen Hao , Bhuiya Abdul M. , Ding Qing , Toussaint Kimani C.
Published: March 2015

We present the first demonstration of the recording of optically encoded audio onto a plasmonic nanostructure. Analogous to the “optical sound” approach used in the early twentieth century to store sound on photographic film, we show that arrays of gold, pillar-supported bowtie nanoantennas could be used in a similar fashion to store sound information that is transferred via an amplitude modulated optical signal to the near field of an optical microscope. Retrieval of the audio information is achieved using standard imaging optics. We demonstrate that the sound information can be stored either as time-varying waveforms or in the frequency domain as the corresponding amplitude and phase spectra. A “plasmonic musical keyboard” comprising of 8 basic musical notes is constructed and used to play a short song. For comparison, we employ the correlation coefficient, which reveals that original and retrieved sound files are similar with maximum and minimum values of 0.995 and 0.342, respectively. We also show that the pBNAs could be used for basic signal processing by ablating unwanted frequency components on the nanostructure thereby enabling physical notch filtering of these components. Our work introduces a new application domain for plasmonic nanoantennas and experimentally verifies their potential for information processing.
Novel Type II and Monomeric NAD+ Specific Isocitrate Dehydrogenases: Phylogenetic Affinity, Enzymatic Characterization and Evolutionary Implication
Authors: Wang Peng , Lv Changqi , Zhu Guoping
Published: March 2015

NAD+ use is an ancestral trait of isocitrate dehydrogenase (IDH) and the NADP+ phenotype arose through evolution as an ancient adaptation event. However, no NAD+-specific IDHs have been found among type II IDHs and monomeric IDHs. In this study, novel type II homodimeric NAD-IDHs from Ostreococcus lucimarinus CCE9901 IDH (OlIDH) and Micromonas sp. RCC299 (MiIDH) and novel monomeric NAD-IDHs from Campylobacter sp. FOBRC14 IDH (CaIDH) and Campylobacter curvus (CcIDH) were reported for the first time. The homodimeric OlIDH and monomeric CaIDH were determined by size exclusion chromatography and MALDI-TOF/TOF mass spectrometry. All the four IDHs were demonstrated to be NAD+-specific, since OlIDH, MiIDH, CaIDH and CcIDH displayed 99-fold, 224-fold, 61-fold and 37-fold preferences for NAD+ over NADP+, respectively. The putative coenzyme discriminating amino acids (Asp326/Met327 in OlIDH, Leu584/Asp595 in CaIDH) were evaluated and the coenzyme specificities of the two mutants, OlIDH R326H327 and CaIDH H584R595, were completely reversed from NAD+ to NADP+. The detailed biochemical properties, including optimal reaction pH and temperature, thermostability and metal ion effects, of OlIDH and CaIDH were further investigated. The evolutionary connections among OlIDH, CaIDH and all the other forms of IDHs were described and discussed thoroughly.
Stabilization of a highly porous metal–organic framework utilizing a carborane-based linker
Authors: Clingerman Daniel J. , Morris William , Mondloch Joseph E. , Kennedy Robert D. , Sarjeant Amy A. , Stern Charlotte , Hupp Joseph T. , Farha Omar K. , Mirkin Chad A.
Published: March 2015

The first tritopic carborane-based linker, H3BCA (C15B24O6H30), based on closo-1,10-C2B8H10, has been synthesized and incorporated into a metal–organic framework (MOF), NU-700 (Cu3(BCA)2).
Conformational steering in dicarboxy acids: the native structure of succinic acid
Authors: Jahn Michaela K. , Méndez Estibaliz , Rajappan Nair K. P. , Godfrey Peter D. , McNaughton Don , Écija Patricia , Basterretxea Francisco J. , Cocinero Emilio J. , Grabow Jens-Uwe
Published: March 2015

The torsional freedom of the carbon backbone and hydroxyl groups induces numerous plausible conformers. Rotational spectroscopy supported by quantum chemical methods evidences that the “folding of methylene unit” is favoured.
Synthesis and aggregation behaviour of luminescent mesomorphic zinc(ii) complexes with ‘salen’ type asymmetric Schiff base ligands
Authors: Chakraborty Sutapa , Bhattacharjee Chira R. , Mondal Paritosh , Prasad S. Krishna , Rao D. S. Shankar
Published: March 2015

Mesomorphism and solvent dependent aggregation behaviour of a new series of photoluminescent Zn(ii)-salen type asymmetric Schiff base complexes have been investigated.
Imaging of drug loading distributions in individual microspheres of calcium silicate hydrate – an X-ray spectromicroscopy study
Authors: Guo Xiaoxuan , Wang Zhiqiang , Wu Jin , Wang Jian , Zhu Ying-Jie , Sham Tsun-Kong
Published: March 2015

Ibuprofen distributions in individual CSH microspheres are being mapped in thickness via scanning transmission X-ray microscopy.
Predictive of the quantum capacitance effect on the excitation of plasma waves in graphene transistors with scaling limit
Authors: Wang Lin , Chen Xiaoshuang , Hu Yibin , Wang Shao-Wei , Lu Wei
Published: March 2015

We study the excitations and propagation properties of plasma waves in nanometric graphene FETs down to the scaling limit. This study reveals the key feature of plasma waves in decorated/nanometric graphene FETs, and paves the way to tailor plasma band-engineering.
Regio- and stereoselective synthesis of α-hydroxy-β-azido tetrazoles
Authors: Quinodoz Pierre , Lo Cheikh , Kletskii Mikhail , Burov Oleg , Marrot Jérôme , Couty François
Published: March 2015

Unreported α-hydroxy-β-azido tetrazoles are prepared in a single step and mild conditions from readily available epoxy nitriles.
The chemical stability of phosphonium-based ionic liquids under gamma irradiation
Authors: Morco Ryan P. , Joseph Jiju M. , Wren J. Clara
Published: March 2015

Photographs of irradiated [P14666][dca] and the corresponding UV-vis and Raman spectra, and conductivities as a function of irradiation time. Black, blue and red lines are for 0, 96 and 192 h of irradiation, respectively.
Highly active 4-aminoquinoline–pyrimidine based molecular hybrids as potential next generation antimalarial agents
Authors: Manohar Sunny , Satya Pavan V. , Taylor Dale , Kumar Deepak , Ponnan Prija , Wiesner Lubbe , Rawat Diwan S.
Published: March 2015

Novel 4-aminoquinoline–pyrimidine based antimalarial hybrids were discovered to show potent activity against NF54 and Dd2 strains ofP. falciparum.
Synergistic enhancement of nitrogen and sulfur co-doped graphene with carbon nanosphere insertion for the electrocatalytic oxygen reduction reaction
Authors: Wu Min , Wang Jie , Wu Zexing , Xin Huolin L. , Wang Deli
Published: March 2015

A nitrogen and sulfur co-doped graphene/carbon black nanocomposite with high electrocatalytic activity for the oxygen reduction reaction and superior long-term stability and methanol tolerance compared to commercial Pt/C.
Mesoporous KIT-6 silica–polydimethylsiloxane (PDMS) mixed matrix membranes for gas separation
Authors: Wang Junhui , Li Yang , Zhang Zhongshen , Hao Zhengping
Published: March 2015

The incorporation of a low percentage of KIT-6 into PDMS membranes can greatly increase the C4H10permeability and C4H10/N2selectivity simultaneously.
A sequence-based two-level method for the prediction of type I secreted RTX proteins
Authors: Luo Jiesi , Li Wenling , Liu Zhongyu , Guo Yanzhi , Pu Xuemei , Li Menglong
Published: March 2015

A two-level method was proposed for accurately identifying the secreted proteins of the type I system based on protein sequence information.
Manganese catalyzed C–H functionalization of indoles with alkynes to synthesize bis/trisubstituted indolylalkenes and carbazoles: the acid is the key to control selectivity
Authors: Shi Lijun , Zhong Xiang , She Houde , Lei Ziqiang , Li Fuwei
Published: March 2015

The Mn-catalyzed C–H alkenylations of indole with terminal- and/or internal-alkynes have been developed to selectively yield indolylalkene and carbazole.
Laser cooling of BH and GaF: insights from an ab initio study
Authors: Gao Yu-feng , Gao Tao
Published: March 2015

The feasibility of laser cooling BH and GaF is investigated usingab initioquantum chemistry.
Functionalization of a GaSe monolayer by vacancy and chemical element doping
Authors: Ao L. , Xiao H. Y. , Xiang X. , Li S. , Liu K. Z. , Huang H. , Zu X. T.
Published: March 2015

The electronic and magnetic properties of the GaSe monolayer can be modified and manipulated through vacancy and chemical element doping.
Lipophilicity-dependent ruthenium N-heterocyclic carbene complexes as potential anticancer agents
Authors: Lv Gaochao , Guo Liubin , Qiu Ling , Yang Hui , Wang Tengfei , Liu Hong , Lin Jianguo
Published: March 2015

Five novel Ru(ii)–N-heterocyclic carbenes (NHC) were synthesized and biologically evaluated, one of which showed superior activity against PC-3 cell lines and 6 fold more activity than cisplatin.
[UO2(NH3)5]Br2·NH3: synthesis, crystal structure, and speciation in liquid ammonia solution by first-principles molecular dynamics simulations
Authors: Woidy Patrick , Bühl Michael , Kraus Florian
Published: March 2015

X-Ray diffraction and Car–Parrinello molecular dynamics simulations furnish insights into the speciation of uranyl(vi) in liquid ammonia, calling special attention to the effect of solvation on the U–N bond length and bond strength.
Catalytic aerobic oxidation of phenols to ortho-quinones with air-stable copper precatalysts
Authors: Askari M. S. , Rodríguez-Solano L. A. , Proppe A. , McAllister B. , Lumb J.-P. , Ottenwaelder X.
Published: March 2015

Air-stable Cu(ii) species are competent precatalysts in the aerobic oxygenation of phenols into ortho-quinones.
Excited-state deactivation mechanisms of protonated and neutral phenylalanine: a theoretical study
Authors: Omidyan Reza , Ataelahi Mitra , Azimi Gholamhassan
Published: March 2015

Minimum energy paths (MEPs) of protonated phenylalanine (PheH+) at the electronic ground and S1 (1ππ*) excited states along the Cα–Cβ bond stretching coordinate, following proton transfer to the aromatic chromophore.
Reduction-induced surface amorphization enhances the oxygen evolution activity in Co3O4
Authors: Leng Xue , Zeng Qingcong , Wu Kuang-Hsu , Gentle Ian R. , Wang Da-Wei
Published: March 2015

Modifying crystalline Co3O4by thermal H2annealing and air exposure produced an amorphous surface layer consisting of mixed hydrated cobalt hydroxide/carbonate species and remarkably enhanced the oxygen evolution activity.
Stabilization of η3-indenyl compounds by sterically demanding N,N-chelating ligands in the molybdenum coordination sphere
Authors: Lodinský Jakub , Vinklárek Jaromír , Dostál Libor , Růžičková Zdeňka , Honzíček Jan
Published: March 2015

A series of η3-indenyl molybdenum compounds, isostructural with the well-known η3-allyl compounds, was synthesized from the recently established synthon [{(η5-4,7-Me2C9H5)Mo(CO)2(μ-Cl)}2].
Structural evolution of OBC/carbon nanotube bundle nanocomposites under uniaxial deformation
Authors: Wu Siduo , Huang Guangsu , Wu Jinrong , Tian Feng , Li Hui
Published: March 2015

A regulated morphology of multi-walled CNT bundles in an olefin block copolymer matrix is achievedviasolution blending after sonication. We observed an unexpected inverse evolution trend of long period in nanocomposites compared to that in neat matrix.
1D hacksaw chain bipyridine–sulfonate Schiff base-dicopper(ii) as a host for variable solvent guests
Authors: Hazra Susanta , Guedes da Silva M. Fátima C. , Karmakar Anirban , Pombeiro Armando J. L.
Published: March 2015

The current study related to five solvatomorphs containing the 1D hacksaw chain of bipyridine–sulfonate Schiff base-dicopper(ii) as a host provides the first example of a polymeric copper(ii) system with five interconvertible solvatomorphic forms.
Reaction routes in catalytic reforming of poly(3-hydroxybutyrate) into renewable hydrocarbon oil
Authors: Kang Shimin , Yu Jian
Published: March 2015

Crotonic acid is a major monomeric intermediate in the H3PO4 catalytic poly(3-hydroxybutyrate) decomposition. Propylene and 2,3-dimethyl-2-cyclopenten-1-one are two key intermediates for formation of the main aromatic products.
A mild and efficient Zn-catalyzed C-glycosylation: synthesis of C(2)–C(3) unsaturated C-linked glycopyranosides
Authors: Reddy Thurpu Raghavender , Rao Dodla Sivanageswara , Kashyap Sudhir
Published: March 2015

A mild and efficient protocol for theC-glycosylation from glycals is described by using Zn-catalysis.
Insight into the role of Li2S2 in Li–S batteries: a first-principles study
Authors: Yang Guochun , Shi Shaoqing , Yang Jinghai , Ma Yanming
Published: March 2015

Li2S2 acts as an intermediate product and spontaneously disproportionates into Li2S plus S in a Li–S battery.
How does the silicon element perform in JD-dyes: a theoretical investigation
Authors: Yang Li-Na , Chen Shi-Lu , Li Ze-Sheng
Published: March 2015

A dithienosilole-containing silicon-core JD analogue (Y2) displays remarkable light-harvesting capability, favorable thermodynamic properties, good kinetic parameters, and high stability for Y2/(TiO2)38.
High-performance hole-transporting layer-free conventional perovskite/fullerene heterojunction thin-film solar cells
Authors: Tsai Kai-Wei , Chueh Chu-Chen , Williams Spencer T. , Wen Ten-Chin , Jen Alex K. Y.
Published: March 2015

MAPbI3 perovskite was found to be able to modify the work function of ITO, leading to sufficient charge extraction efficiency at the ITO/perovskite interface. A device with a high power conversion efficiency of >11% was obtained.
Temporal Processing Deficits in Middle Age
Authors: Grose John H. , Mamo Sara K. , Buss Emily , Hall Joseph W.
Published: March 2015

Purpose

The purpose of this brief report is to provide a synopsis of recent work, primarily from the authors' laboratory, that points to the emergence of temporal processing deficits relatively early in the aging process.

Method

The approach taken was to provide a descriptive summary of selected published and current experiments focusing on the processing of temporal envelopes and fine structure.

Conclusion

Deficits in both temporal envelope and temporal fine structure processing are evident during middle age even while audiometric hearing sensitivity remains normal.
Quantifying the Robustness of the English Sibilant Fricative Contrast in Children
Authors: Holliday Jeffrey J. , Reidy Patrick F. , Beckman Mary E. , Edwards Jan
Published: March 2015

Purpose

Four measures of children's developing robustness of phonological contrast were compared to see how they correlated with age, vocabulary size, and adult listeners' correctness ratings.

Method

Word-initial sibilant fricative productions from eighty-one 2- to 5-year-old children and 20 adults were phonetically transcribed and acoustically analyzed. Four measures of robustness of contrast were calculated for each speaker on the basis of the centroid frequency measured from each fricative token. Productions that were transcribed as correct from different children were then used as stimuli in a perception experiment in which adult listeners rated the goodness of each production.

Results

Results showed that the degree of category overlap, quantified as the percentage of a child's productions whose category could be correctly predicted from the output of a mixed-effects logistic regression model, was the measure that correlated best with listeners' goodness judgments.

Conclusions

Even when children's productions have been transcribed as correct, adult listeners are sensitive to within-category variation quantified by the child's degree of category overlap. Further research is needed to explore the relationship between the age of a child and adults' sensitivity to different types of within-category variation in children's speech.
Band excitation Kelvin probe force microscopy utilizing photothermal excitation
Authors: Collins Liam , Jesse Stephen , Balke Nina , Rodriguez Brian J. , Kalinin Sergei , Li Qian
Published: March 2015

A multifrequency open loop Kelvin probe force microscopy (KPFM) approach utilizing photothermal as opposed to electrical excitation is developed. Photothermal band excitation (PthBE)-KPFM is implemented here in a grid mode on a model test sample comprising a metal-insulator junction with local charge-patterned regions. Unlike the previously described open loop BE-KPFM, which relies on capacitive actuation of the cantilever, photothermal actuation is shown to be highly sensitive to the electrostatic force gradient even at biases close to the contact potential difference (CPD). PthBE-KPFM is further shown to provide a more localized measurement of true CPD in comparison to the gold standard ambient KPFM approach, amplitude modulated KPFM. Finally, PthBE-KPFM data contain information relating to local dielectric properties and electronic dissipation between tip and sample unattainable using conventional single frequency KPFM approaches.
Impact of implementing the Meyer-Neldel behavior of carrier emission pre-factors in solar cell and optical detector modeling
Authors: Rubinelli Francisco A. , Ramirez Helena
Published: March 2015

The Meyer-Neldel behavior reported for the emission probabilities of electrons and holes was included in our code, replacing the gap state capture cross sections of the Shockley-Read-Hall formalisms with capture cross sections containing an exponential function of the trap energy depth. The Meyer-Neldel energies for electrons and holes are the slopes of these exponentials. Our results indicate that emission probabilities of neutral states no deeper than approximately 0.45 eV and 0.37 eV from the conduction and valence band edges, respectively, can show a Meyer-Neldel behavior only, while on the other hand, its implementation in deeper gap states makes the replication of experimental J-V curves of p-i-n solar cells and detectors impossible. The Meyer-Neldel behavior can be included in all neutral capture cross sections of acceptor-like tail states without affecting the J-V characteristics, while it cannot be included in all capture cross sections of neutral donor-like tail states and/or defect states without predicting device performances below the experimental figures, that become even lower when it is also included in charged capture cross sections. The implementation of the anti Meyer-Neldel behavior at tail states gives rise to slightly better and reasonable device performances.
Matrix Painlevé systems
Authors: Kawakami Hiroshi
Published: March 2015

We study a class of the isomonodromic deformation equations, which we call matrix Painlevé systems. They can be written in Hamiltonian form. The Hamiltonian is written as the trace of the Hamiltonian of the sixth Painlevé equation with canonical variables replaced by matrices. We also derive the matrix version of the fifth, fourth, third, and second Painlevé equation from the sixth matrix Painlevé system by the degeneration.
Demonstration of a high-performance pulsed optically pumped Rb clock based on a compact magnetron-type microwave cavity
Authors: Kang S. , Gharavipour M. , Affolderbach C. , Gruet F. , Mileti G.
Published: March 2015

We demonstrate a high-performance pulsed optically pumped (POP) Rb vapor-cell clock based on a magnetron-type microwave cavity of only 44 cm3 external volume. Using optical detection, an unprecedented 35% contrast of the Ramsey signal has been obtained. Both the signal-to-noise ratio (of 30 000) and the estimated shot-noise limit of 1.7 × 10−14 τ−1/2 are at the same level as those found with a bigger cylindrical TE011 cavity (100 cm3 inner volume) and are sufficient for achieving excellent clock stability. Rabi oscillations are measured and indicate a sufficiently uniform microwave magnetic field distribution inside the cavity. The instability sources for the POP clock's performance are analyzed. A short-term stability of 2.1 × 10−13 τ−1/2 is demonstrated which is consistent with the noise budget.
Reconstruction of apparent orthotropic conductivity tensor image using magnetic resonance electrical impedance tomography
Authors: Sajib Saurav Z. K. , Kim Ji Eun , Jeong Woo Chul , Kim Hyung Joong , Kwon Oh In , Woo Eung Je
Published: March 2015

Magnetic resonance electrical impedance tomography visualizes current density and/or conductivity distributions inside an electrically conductive object. Injecting currents into the imaging object along at least two different directions, induced magnetic flux density data can be measured using a magnetic resonance imaging scanner. Without rotating the object inside the scanner, we can measure only one component of the magnetic flux density denoted as Bz. Since the biological tissues such as skeletal muscle and brain white matter show strong anisotropic properties, the reconstruction of anisotropic conductivity tensor is indispensable for the accurate observations in the biological systems. In this paper, we propose a direct method to reconstruct an axial apparent orthotropic conductivity tensor by using multiple Bz data subject to multiple injection currents. To investigate the anisotropic conductivity properties, we first recover the internal current density from the measured Bz data. From the recovered internal current density and the curl-free condition of the electric field, we derive an over-determined matrix system for determining the internal absolute orthotropic conductivity tensor. The over-determined matrix system is designed to use a combination of two loops around each pixel. Numerical simulations and phantom experimental results demonstrate that the proposed algorithm stably determines the orthotropic conductivity tensor.
Nano-needle structured, ambipolar high electrical conductivity SnOx (x ≤ 1) thin films for infrared optoelectronics
Authors: Wong Andrew , Wang Xiaoxin , Liu Jifeng
Published: March 2015

SnO has become an important earth-abundant transparent conductive oxide (TCO) with applications not only in photovoltaics but also in electrodes for energy storage. For optoelectronic applications, low fabrication temperature, high electrical conductivity, and low optical losses are highly desirable. This study presents self-assembled, ambipolar (i.e., n and p-type) nano-needle structured SnOx (x ≤ 1) thin films with high electrical conductivity, low infrared (IR) optical losses, and potentials for effective light trapping. These nano-needle structured SnOx films are fabricated through non-reactive co-sputtering of Sn and SnO2 followed by crystallization annealing at low temperatures <250 °C. The crystallization of SnOx thin films occurred rapidly above 210 °C, resulting in SnO nano-needles with average dimensions of 1 μm long, 0.1 μm wide, and 0.15 μm thick that are interspersed with Sn nanocrystals. The optical scattering from these nanostructures can be utilized for light trapping in thin film absorbers. We also found that laser pre-patterning enabled control over nano-needle crystal size and growth directions. The electrical conductivity of 1500–2000 S/cm is comparable to state-of-the-art SnO2:F TCOs while the fabrication temperature is reduced by ∼200 °C, enabling a broader range of applications, such as optoelectronics on flexible substrates. Hall effect measurements show an intriguing ambipolar behavior depending on the annealing ambient. Especially, a strong p-type conductivity with a hole concentration of p ∼ 5 × 1021 cm−3 and mobility μp ∼ 2 cm2 V−1 s−1 is obtained in a weak oxidizing ambient. Such a high p-type conductivity is particularly rare in TCOs, and it offers potential applications in bipolar oxide semiconductor devices. Optical measurements showed a low absorption loss of <3% in a broad IR wavelength regime of λ = 1100–2500 nm for p-type SnOx, suggesting that these nano-needle structured SnOx TCOs can be engineered to enhance low-loss optical scattering/light trapping in thin film thermophotovoltaic cells and IR photodetectors.
Magnetic resonance imaging without field cycling at less than earth's magnetic field
Authors: Lee Seong-Joo , Shim Jeong Hyun , Kim Kiwoong , Yu Kwon Kyu , Hwang Seong-min
Published: March 2015

A strong pre-polarization field, usually tenths of a milli-tesla in magnitude, is used to increase the signal-to-noise ratio in ordinary superconducting quantum interference device-based nuclear magnetic resonance/magnetic resonance imaging experiments. Here, we introduce an experimental approach using two techniques to remove the need for the pre-polarization field. A dynamic nuclear polarization (DNP) technique enables us to measure an enhanced resonance signal. In combination with a π/2 pulse to avoid the Bloch-Siegert effect in a micro-tesla field, we obtained an enhanced magnetic resonance image by using DNP technique with a 34.5 μT static external magnetic field without field cycling. In this approach, the problems of eddy current and flux trapping in the superconducting pickup coil, both due to the strong pre-polarization field, become negligible.
Formation of collisional sheath in electronegative plasma with two species of positive ions
Authors: Moulick R. , Goswami K. S.
Published: March 2015

Sheath formation is investigated for electronegative plasma in presence of two species of positive ions in collisional environment. The gas under consideration is a mixture of oxygen and argon. Argon is the considered as having fixed volume and impact of collision is studied with increasing pressure of oxygen. Fluid equations are solved for three species namely, the two positive ions and a negative ion. Electrons are considered to follow Boltzmann distribution. Collision is modeled by constant mean free path model and has been used as a parameter. It has been found that collision enhances the sheath formation. The negative ion core is nearly unaffected by the presence of collision and is governed by the electric potential. The negative flux field is, however, affected by the presence of collision and shows a steady behavior in front of the wall. The two positive ions are heavily affected by the presence of collision and the modeling is such that their equilibrium densities can be estimated by solving simultaneous cubic equations.
Structural properties of Ge on SrTiO3 (001) surface and Ge/SrTiO3 interface
Authors: Pu Long , Wang Jianli , Tang Gang , Zhang Junting
Published: March 2015

Germanium−perovskite oxide heterostructures have a strong potential for next-generation low-voltage and low-leakage metal-oxide semiconductor field-effect transistors. We investigated the atomic structure and electronic properties of Ge on perfect and defective (001) SrTiO3 by first-principle calculations. The specific adsorption sites at the initial growth stage and the atomic structure of Ge on the SrTiO3 (001) substrate have been systematically investigated. The surface grand potential was calculated and compared as a function of the relative chemical potential. The complete surface phase diagram was presented. The energetically favorable interfaces were pointed out among the atomic arrangements of the Ge/SrTiO3 (001) interfaces. The atomic structure and electronic properties of the intrinsic point defects were calculated and analyzed for the Ge/SrTiO3 (001) interfaces.