bluuebunny/crossref_metadata_2025 huggingface dataset:
In situ synthesis of silver nanostructures on magnetic Fe3O4@organosilicon microparticles for rapid hydrogenation catalysis
Authors: Zhao Songfang , Gao Yongju , Li Jinhui , Zhang Guoping , Sun Rong , Wong Ching-Ping
Published: June 2015

A novel protocol for multifunctional magnetic Fe3O4@Si/Ag is developed, which shows excellent catalytic activity and recyclability in reducing diverse dyes.
Facilely tuning the bioactivity of an orthopedic implant surface based on nanostructured polypyrrole/glycosaminoglycans
Authors: Zhu Zhaojin , Wang Yongping , Liu Jingfeng , Chen Gang , Zhu Yuan , Xu Xiangyang
Published: June 2015

The wettability of nanostructured polypyrrole/glycosaminoglycans can be controlled in situ by electrical stimulus to tune the bioactivity of implants.
l-Cysteine tailored porous graphene aerogel for enhanced power generation in microbial fuel cells
Authors: Qiao Yan , Wen Guo-Yun , Wu Xiao-Shuai , Zou Long
Published: June 2015

l-Cysteine tailored porous graphene aerogel anode possesses three dimensional pore structures and biocompatibility surface for increased biocatalyst loading and thus achieves high power density inS. putrefaciensmicrobial fuel cells.
Cobalt(iii) acetylacetonate initiated RAFT polymerization of acrylonitrile and its application in removal of methyl orange after electrospinning
Authors: Xu Yuanyuan , Sun Jinming , Chen Hou , Bai Liangjiu
Published: June 2015

Electrostatic repulsion (ER) played a key role at low solution pH. Enhancement of hydrophobic attraction (HA) and hydrogen bond (HB) increased the adsorption capacity at higher solution pH.
Asymmetric transfer hydrogenation of α-amino β-keto ester hydrochlorides through dynamic kinetic resolution
Authors: Echeverria Pierre-Georges , Cornil Johan , Férard Charlène , Guérinot Amandine , Cossy Janine , Phansavath Phannarath , Ratovelomanana-Vidal Virginie
Published: June 2015

The development of Ru-catalyzed asymmetric transfer hydrogenation of α-amino β-keto ester hydrochlorides is described.
Bulk solvent extraction of biomass slurries using a lipid trap
Authors: Schoepp Nathan G. , Wong Wilson , Mayfield Stephen P. , Burkart Michael D.
Published: June 2015

Simple and rapid extraction of lipids and hydrophobic metabolites from unmodified microbial and plant aqueous slurries was accomplished at a scale larger than ever previously reported.
Enantioselective gold-catalyzed intermolecular [2+2] versus [4+2]-cycloadditions of 3-styrylindoles with N-allenamides: observation of interesting substituent effects
Authors: Wang Yidong , Zhang Peichao , Liu Yuan , Xia Fei , Zhang Junliang
Published: June 2015

The cycloaddition mode ([2+2] vs. [4+2]) can be unexpectedly switched by the simple modification of the N-substituent of the 3-styrylindoles.
A multilayer coating with optimized properties for corrosion protection of Al
Authors: Khelifa Farid , Ershov Sergey , Druart Marie-Eve , Habibi Youssef , Chicot Didier , Olivier Marie-Georges , Snyders Rony , Dubois Philippe
Published: June 2015

A barrier multilayer coating comprising of a plasma polymer film, a grafted layer and a mechanically reinforced acrylic layer is reported in this work.
Amorphous Co-doped MoS2 nanosheet coated metallic CoS2 nanocubes as an excellent electrocatalyst for hydrogen evolution
Authors: Zhang Haichuan , Li Yingjie , Xu Tianhao , Wang Jiabao , Huo Ziyang , Wan Pengbo , Sun Xiaoming
Published: June 2015

Amorphous Co-doped MoS2 nanosheet coated metallic CoS2 nanocubes with ultrahigh HER activity were prepared via one-pot hydrothermal synthesis.
Binding performance of pepsin surface-imprinted polymer particles in protein mixtures
Authors: Pluhar B. , Ziener U. , Mizaikoff B.
Published: June 2015

Surface-imprinted polymer particles were preparedviaminiemulsion polymerization. They provide high binding capacities, fast rebinding kinetics and selective rebinding of the target protein investigated by batch rebinding experiments.
Near‐zero dead zone phase frequency detector with wide input frequency difference
Authors: Strzelecki J. , Ren S.
Published: June 2015

An all‐digital phase frequency detector design capable of accepting an infinite range of input frequency differences and [0 2π] radians input phase difference is presented. The proposed phase frequency detector design minimises the dead zone, supresses unwanted output glitches, achieves a high maximum operating frequency, can drive high‐capacitive loads and avoids differential outputs. The proposed phase frequency detector takes advantage of a fast reset operation from modified tristate inverters acting as a D flip‐flop. Simulation results indicate that the design can detect input phase differences as small as 750 fs apart for all process corners at input operating frequencies of 38 kHz–2.5 GHz in 1.2 V, 90 nm CMOS technology.
Very low thermal drift precision virtual voltage reference
Authors: Crovetti P.S.
Published: June 2015

A digital‐based, process‐supply‐and‐temperature independent voltage reference suitable to nanoscale CMOS technologies, which exploits the recently proposed ‘virtual reference’ concept to achieve a very low thermal drift, is presented. Its performance is assessed on the basis of simulations and experiments carried out on a microcontroller‐based, proof‐of‐concept prototype and is compared with state‐of‐the‐art integrated analogue and digital voltage references. A simulated (measured) thermal drift as low as 1 ppm/°C (5 ppm/°C) in the temperature range −40/+140°C (−10/+100°C) is reported.
Suppression of sublinearity of light–current curve in 850 nm quantum well laser with asymmetric barrier layers
Authors: Zubov F.I. , Maximov M.V. , Shernyakov Yu.M. , Kryzhanovskaya N.V. , Semenova E.S. , Yvind K. , Asryan L.V. , Zhukov A.E.
Published: June 2015

An AlGaAs/GaAs quantum well (QW) laser is fabricated with GaInP and AlGaInAs asymmetric barrier layers (ABLs) and its light–current characteristic (LCC) is compared with that of a reference conventional QW laser without ABLs. It was found that the use of the ABLs suppresses the sublinearity of the LCC at high current densities. As a result, the maximum lasing power of 9.2 W, being limited by catastrophic optical mirror damage, is achieved at a considerably lower operating current in the laser with ABLs as compared to the reference laser (12.5 against 20.2 A). The ABL effect is associated with the suppression of the parasitic recombination in the optical confinement layer, as confirmed by a decrease of the intensity of the spontaneous emission from the layer.
Efficient channel access scheme for multiuser parallel transmission under channel bonding in IEEE 802.11ac
Authors: Fang Juan , Lu I‐Tai
Published: June 2015

Channel bonding proposed in IEEE 802.11ac has the potential to multiply the physical data rate with wider bandwidths. However, the backward compatibility with legacy 802.11 devices makes the available frequency resource severely underutilised. Furthermore, the design that allocates the entire extended bandwidth to a single user is very inefficient when the frame size is very small. In this study, the authors propose a novel channel access scheme, which has successfully mitigated these two problems by scheduling multiuser parallel transmission in both downlink and uplink. Simulation results show that the proposed scheme can improve the spectral efficiency of 801.11ac dramatically. In addition, same as the scheme in the 802.11ac draft, the proposed scheme guarantees the backward compatibility with legacy 802.11 devices, remains distributed and contention based and has the capability to multiply the physical data rates for 802.11ac devices.
Enhanced fast compressive tracking based on adaptive measurement matrix
Authors: Gao Yun , Zhou Hao , Zhang Xuejie
Published: June 2015

Robust object tracking is a challenging task because of factors such as pose variation, illumination changes, abrupt motion and background clutter across the video sequence. With the introduction of the compressive sensing theory, researchers are provided with a new and effective way of real‐time object tracking. In this study, an enhanced fast compressive tracking based on an adaptive measurement matrix is presented, which the authors have named ‘adaptive fast compressive tracking’ (AFCT). The sparsity of the matrix and the number of columns are adaptively determined according to the dimension of the Haar‐like feature. This measurement matrix is fixed once it has been calculated when selecting a tracked rectangle region in the first frame. Unlike most of the existing compressive trackers, the proposed method adopts a different adaptive measurement matrix for a different targeting object. Compared with the fast compressive tracking (FCT), each measurement element contains more information for the original signal. As a result, stable object tracking is achieved by using fewer measurement elements. The proposed AFCT method can run in real time and outperforms FCT on many challenging video sequences in terms of efficiency, accuracy and robustness.
Improved centroid extraction algorithm for autonomous star sensor
Authors: Luo Liyan , Xu Luping , Zhang Hua
Published: June 2015

An improved centroid extraction algorithm for autonomous star sensor is proposed in this study, which focuses on the improvements of the location accuracy of stars and the speed of the centroid extraction. First, the coarse positioning of stars is carried out to achieve the dispersive regions of the stars quickly. Then the stars pixels are chosen by the automatic seeded region growing algorithm. Subsequently, in order to restrain the interference of noise, the grey values of the stars pixels are modified according to the characteristics of the star energy distribution. Finally, the fine positioning of the star can be achieved using the proposed centroid calculation formula. Experimental results show that the proposed algorithm has high‐positioning accuracy and good noise resistant ability compared with the other two centroid extraction algorithms. Moreover, the computational complexity of the proposed algorithm is lower than that of the other two algorithms.
Revised spectral matching algorithm for scenes with mutually inconsistent local transformations
Authors: Chen Peizhi , Li Xin
Published: June 2015

Spectral matching (SM) is an efficient and effective greedy algorithm for solving the graph matching problem in feature correspondence in computer vision and graphics. However, the classic SM algorithm cannot extract correspondences well when the affinity matrix is sparse and reducible (i.e. its corresponding graph is not connected). This case often happens when the geometric deformations consist of transformations with local inconsistency. The authors analyse this problem and show how the original SM could fail in this scenario. Then, the authors propose a revised two‐step pipeline to tackle this issue: (1) decompose the mutually inconsistent local deformations into several consistent transformations which can be solved by individual SM; (2) filter out incorrect correspondences through an automatic thresholding. The authors perform experiments to demonstrate that this modification can effectively handle the coarse correspondence computation in shape or image registration where the global transformation consists of multiple inconsistent local transformations.
Combination of contrast limited adaptive histogram equalisation and discrete wavelet transform for image enhancement
Authors: Lidong Huang , Wei Zhao , Jun Wang , Zebin Sun
Published: June 2015

Image enhancement has an important role in image processing applications. Contrast limited adaptive histogram equalisation (CLAHE) is an effective algorithm to enhance the local details of an image. However, it faces the contrast overstretching and noise enhancement problems. To solve these problems, this study presents a novel image enhancement method, named CLAHE‐discrete wavelet transform (DWT), which combines the CLAHE with DWT. The new method includes three main steps: First, the original image is decomposed into low‐frequency and high‐frequency components by DWT. Then, the authors enhance the low‐frequency coefficients using CLAHE and keep the high‐frequency coefficients unchanged to limit noise enhancement. This is because the high‐frequency component corresponds to the detail information and contains most noises of original image. Finally, reconstruct the image by taking inverse DWT of the new coefficients. To alleviate over‐enhancement, the reconstructed and original images are averaged using an originally proposed weighting factor. The weighting operation can control the enhancement levels of regions with different luminances in original image adaptively. This is important because bright parts of image are usually needless to be enhanced in comparison with the dark parts. Extensive experiments show that this method performs well in detail preservation and noise suppression.
Evaluation of a multi‐modal driver coaching function for electric vehicles
Authors: Jagiellowicz‐Kaufmann Monika , Hammer Thomas , Hanig Michael , Schmitz Marcus
Published: June 2015

Several different driver coaching approaches exist that aim at supporting eco‐friendly driving. Most of these approaches have been designed for vehicles with combustion engines and could therefore not be simply adapted to fully electric vehicles (FEVs) because of the different vehicle architecture. The study at hand outlines a driver coaching function that has been developed especially for FEVs. The function aims at promoting an efficient driving style and thus should support the driver optimise energy consumption and remaining range. The coaching function provides specific real‐time feedback via head‐up display addressing several different aspects of the driver behaviour. In addition, the coaching advice is also used to trigger an active accelerator pedal in order to address an additional feedback channel for the driver coaching. A driver coaching study was then conducted to evaluate the coaching concept and to compare it with two further common coaching approaches. The study results show a significant improvement of energy efficiency as well as the usefulness and high acceptance of the specific driver coaching function. The results could also show the potential of the active forced‐feedback pedal as a reasonable feedback channel for driver coaching.
Duty cycle‐based three‐level space‐vector pulse‐width modulation with overmodulation and neutral‐point balancing capabilities for three‐phase neutral‐point clamped inverters
Authors: Zhu Rongwu , Wu Xiaojie , Tang Yi
Published: June 2015

In this study, a duty cycle‐based space‐vector pulse‐width modulation (SVPWM) with overmodulation and capacitor voltage balance control for three‐phase three‐level neutral‐point clamped (NPC) inverters is presented. On the basis of simple linear calculations of three‐phase reference voltages, the proposed SVPWM can be derived, which avoids the trigonometry operation required by the conventional SVPWM. The modulation region can also be smoothly extended from the linear region to the overmodulation region through re‐synthesising the three‐phase reference voltages. This avoids the conventional non‐linear function and look‐up table. The neutral‐point voltage balancing control is achieved via changing the duty cycle of the redundant small vectors in each switching period, which can be easily embedded into the proposed duty cycle‐based SVPWM. The dynamic and steady‐state performances of the proposed SVPWM are eventually verified by both simulation and experimental results.
Carrierless pulse width modulation strategy for multilevel inverters
Authors: Thamizharasan Sandirasegarane , Sudha Latchumanan Usha , Baskaran Jeevarathinam , Ramkumar Subburam , Jeevananthan Seenithangam
Published: June 2015

This study develops a pulse width modulation (PWM) strategy with a view to achieve explicit control of voltage and accrue a minimum total harmonic distortion in a multilevel inverter (MLI) of any preferred level. The multi objective digital formulation tailors to facilitate discrimination of pulses for various levels and equalise the switching losses in all the power switches in the MLI. The philosophy of the method centres to calculate the pulses for the desired target fundamental output voltage based on equal area criteria. It excludes the need for a carrier in the generation of the PWM pulses through a process of matching the output level with the sectionalised dc levels and travels to determine the switching instants using mathematical relations. It includes simulation results from a MATLAB platform for a seven level MLI and avails the use of a field programmable gate array‐based prototype to validate the findings.
Non-Newtonian behavior and molecular structure of Cooee bitumen under shear flow: A non-equilibrium molecular dynamics study
Authors: Lemarchand Claire A. , Bailey Nicholas P. , Todd Billy D. , Daivis Peter J. , Hansen Jesper S.
Published: June 2015

The rheology and molecular structure of a model bitumen (Cooee bitumen) under shear are investigated in the non-Newtonian regime using non-equilibrium molecular dynamics simulations. The shear viscosity, normal stress differences, and pressure of the bitumen mixture are computed at different shear rates and different temperatures. The model bitumen is shown to be a shear-thinning fluid at all temperatures. In addition, the Cooee model is able to reproduce experimental results showing the formation of nanoaggregates composed of stacks of flat aromatic molecules in bitumen. These nanoaggregates are immersed in a solvent of saturated hydrocarbon molecules. At a fixed temperature, the shear-shinning behavior is related not only to the inter- and intramolecular alignments of the solvent molecules but also to the decrease of the average size of the nanoaggregates at high shear rates. The variation of the viscosity with temperature at different shear rates is also related to the size and relative composition of the nanoaggregates. The slight anisotropy of the whole sample due to the nanoaggregates is considered and quantified. Finally, the position of bitumen mixtures in the broad literature of complex systems such as colloidal suspensions, polymer solutions, and associating polymer networks is discussed.
Effects of trapped electrons on ion reflection in an oblique shock wave
Authors: Toida Mieko , Inagaki Junya
Published: June 2015

A magnetosonic shock wave propagating obliquely to an external magnetic field can trap electrons and accelerate them to ultrarelativistic energies. The trapped electrons excite two-dimensional (2D) electromagnetic fluctuations with finite wavenumbers along the shock front. We study effects of the trapped electrons on ion motions through the 2D fluctuations. It is analytically shown that the fraction of ions reflected from the shock front is enhanced by the 2D fluctuations. This is confirmed by 2D (two space coordinates and three velocities) relativistic, electromagnetic particle simulations with full ion and electron dynamics and calculation of test ions in the electromagnetic fields averaged along the shock front. A comparison between 2D and one-dimensional electromagnetic particle simulations is also shown.
Two-band model interpretation of the p- to n-transition in ternary tetradymite topological insulators
Authors: Chasapis T. C. , Koumoulis D. , Leung B. , Calta N. P. , Lo S.-H. , Dravid V. P. , Bouchard L.-S. , Kanatzidis M. G.
Published: June 2015

The requirement for large bulk resistivity in topological insulators has led to the design of complex ternary and quaternary phases with balanced donor and acceptor levels. A common feature of the optimized phases is that they lie close to the p- to n-transition. The tetradymite Bi2Te3−xSex system exhibits minimum bulk conductance at the ordered composition Bi2Te2Se. By combining local and integral measurements of the density of states, we find that the point of minimum electrical conductivity at x = 1.0 where carriers change from hole-like to electron-like is characterized by conductivity of the mixed type. Our experimental findings, which are interpreted within the framework of a two-band model for the different carrier types, indicate that the mixed state originates from different types of native defects that strongly compensate at the crossover point.
Strong photoluminescence of the porous silicon with HfO2-filled microcavities
Authors: Jiang Ran , Wu Zhengran , Du Xianghao , Han Zuyin , Sun Weideng
Published: June 2015

Greatly enhanced blue emission was observed at room temperature in the single-crystal silicon with HfO2 filled into its microcavities. The broad blue band light was emitted from both the HfO2 dielectric and the porous Si. The ferroelectricity of HfO2 enhances the blue emission from Si by its filling into the microcaivities. At the same time, HfO2 contributes to the light emission for the transitions of the defect levels for oxygen vacancy. The observation of greatly enhanced blue light emission of the porous Si filled with HfO2 dielectric is remarkable as both HfO2 and Si are highly compatible with Si-based electronic industry.
Hydration state inside HeLa cell monolayer investigated with terahertz spectroscopy
Authors: Shiraga K. , Suzuki T. , Kondo N. , Tanaka K. , Ogawa Y.
Published: June 2015

The hydration state in living cells is believed to be associated with various cellular activities. Nevertheless, in vivo characterization of intracellular hydration state under physiological condition has not been well documented to date. In this study, the hydration state of an intact HeLa cell monolayer was investigated by terahertz time-domain attenuated total reflection spectroscopy. Combined with the extended theory of Onsager, we found 23.8 ± 7.4% of HeLa intracellular water was hydrated to biomolecules (corresponding to 1.25 g H2O/g solute); exhibiting slower relaxation dynamics than bulk water.
Cloning SU8 silicon masters using epoxy resins to increase feature replicability and production for cell culture devices
Authors: Kamande J. W. , Wang Y. , Taylor A. M.
Published: June 2015

In recent years, there has been a dramatic increase in the use of poly(dimethylsiloxane) (PDMS) devices for cell-based studies. Commonly, the negative tone photoresist, SU8, is used to pattern features onto silicon wafers to create masters (SU8-Si) for PDMS replica molding. However, the complexity in the fabrication process, low feature reproducibility (master-to-master variability), silane toxicity, and short life span of these masters have been deterrents for using SU8-Si masters for the production of cell culture based PDMS microfluidic devices. While other techniques have demonstrated the ability to generate multiple devices from a single master, they often do not match the high feature resolution (∼0.1 μm) and low surface roughness that soft lithography masters offer. In this work, we developed a method to fabricate epoxy-based masters that allows for the replication of features with high fidelity directly from SU8-Si masters via their PDMS replicas. By this method, we show that we could obtain many epoxy based masters with equivalent features to a single SU8-Si master with a low feature variance of 1.54%. Favorable feature transfer resolutions were also obtained by using an appropriate Tg epoxy based system to ensure minimal shrinkage of features ranging in size from ∼100 μm to <10 μm in height. We further show that surface coating epoxy masters with Cr/Au lead to effective demolding and yield PDMS chambers that are suitable for long-term culturing of sensitive primary hippocampal neurons. Finally, we incorporated pillars within the Au-epoxy masters to eliminate the process of punching media reservoirs and thereby reducing substantial artefacts and wastage.
Phenomenology and control of buckling dynamics in multicomponent colloidal droplets
Authors: Pathak Binita , Basu Saptarshi
Published: June 2015

Self-assembly of nano sized particles during natural drying causes agglomeration and shell formation at the surface of micron sized droplets. The shell undergoes sol-gel transition leading to buckling at the weakest point on the surface and produces different types of structures. Manipulation of the buckling rate with inclusion of surfactant (sodium dodecyl sulphate, SDS) and salt (anilinium hydrochloride, AHC) to the nano-sized particle dispersion (nanosilica) is reported here in an acoustically levitated single droplet. Buckling in levitated droplets is a cumulative, complicated function of acoustic streaming, chemistry, agglomeration rate, porosity, radius of curvature, and elastic energy of shell. We put forward our hypothesis on how buckling occurs and can be suppressed during natural drying of the droplets. Global precipitation of aggregates due to slow drying of surfactant-added droplets (no added salts) enhances the rigidity of the shell formed and hence reduces the buckling probability of the shell. On the contrary, adsorption of SDS aggregates on salt ions facilitates the buckling phenomenon with an addition of minute concentration of the aniline salt to the dispersion. Variation in the concentration of the added particles (SDS/AHC) also leads to starkly different morphologies and transient behaviour of buckling (buckling modes like paraboloid, ellipsoid, and buckling rates). Tuning of the buckling rate causes a transition in the final morphology from ring and bowl shapes to cocoon type of structure.
Assessing the thermoelectric properties of CuxO (x = 1 to 2) thin films as a function of composition
Authors: Hartung D. , Gather F. , Hering P. , Kandzia C. , Reppin D. , Polity A. , Meyer B. K. , Klar P. J.
Published: June 2015

Series of CuxO thin-films in the entire range of compositions 1≤x≤2 were obtained by varying the oxygen flux in an rf-sputter deposition process. Growth windows for three crystalline phases, i.e., the thermodynamically stable cuprous oxide Cu2O and cupric oxide CuO as well as the metastable paramelaconite Cu4O3, were observed. The crystalline phases persist non-stoichiometrically over a wide range of compositions. These flux-range windows are separated by ranges where highly disordered, almost amorphous material is obtained. All samples were analysed with respect to their thermoelectric properties, i.e., Seebeck coefficient, electrical, and thermal conductivity. Clear trends of these transport parameters were found and used to determine the thermoelectric figure of merit ZT. The ZT-values at room temperature are highest for the two thermodynamically stable crystalline phases CuO and Cu2O.
Detection of in-depth helical spin structures by planar Hall effect
Authors: Basaran Ali C. , Morales R. , Guénon S. , Schuller Ivan K.
Published: June 2015

We developed a method to determine the magnetic helicity and to study reversal mechanisms in exchange biased nanostructures using Planar Hall Effect (PHE). As a test case, we use an in-depth helical spin configuration that occurs during magnetization reversal in exchange coupled Ni/FeF2 heterostructures. We show the way to induce and determine the sign of the helicity from PHE measurements on a lithographically patterned cross. The helicity sign can be controlled by the angle between the externally applied magnetic field and a well-defined unidirectional anisotropy axis. Furthermore, the PHE signal reveals complex reversal features due to small deviations of the local unidirectional anisotropy axes from the crystallographic easy axis. The simulations using an incomplete domain wall model are in excellent agreement with the experimental data. These studies show that helical spin formations in nanomagnetic systems can be studied using laboratory-based magnetotransport.
Enhanced memory consolidation in mice lacking the circadian modulators Sharp1 and -2 caused by elevated Igf2 signaling in the cortex
Authors: Shahmoradi Ali , Radyushkin Konstantin , Rossner Moritz J.
Published: June 2015

Significance

SHARP1 and SHARP2 transcription factors are modulators of the sleep/wake homeostasis. Sleep is thought to be important for efficient memory consolidation by gradual stabilization of hippocampus-dependent memory traces in stable cortical modules. Here, SHARP1 and SHARP2 single and double null mutant mice were investigated in cognitive processing. SHARP1 and SHARP2 double null mutants show enhanced cortex-dependent remote fear memory formation, although hippocampus-dependent recent fear memory formation is not changed. Molecular analyses revealed that insulin-related growth factor 2 (IGF2)/MAPK signaling is elevated in the cortex of double mutants and that IGF2 overexpression in the anterior cingulate cortex is sufficient to enhance fear memory consolidation. Our analyses provide evidence that the control of sleep and memory consolidation may share common molecular mechanisms.
Structural dynamics and energetics underlying allosteric inactivation of the cannabinoid receptor CB
1
Authors: Fay Jonathan F. , Farrens David L.
Published: June 2015

Significance

G protein-coupled receptors (GPCRs) are a major pharmaceutical target. Traditionally, they were thought to lead a binary existence, adopting either an off (inactive) or on (active) state. However, recent evidence suggests GPCRs can adopt multiple conformations and these might explain biased signaling—the phenomena where different drugs binding to the same orthosteric site on the receptor can cause activation of different signaling pathways, such as β-arrestin signaling. We show a previously unidentified structure is induced in the marijuana receptor CB
1
by an unusual allosteric ligand that blocks G-protein signaling but increases agonist binding and elicits biased signaling. We propose that a common structural state may exist for β-arrestin biased signaling, one that can also be attained by allosteric ligand binding.
Effect of salt on the H-bond symmetrization in ice
Authors: Bove Livia Eleonora , Gaal Richard , Raza Zamaan , Ludl Adriaan-Alexander , Klotz Stefan , Saitta Antonino Marco , Goncharov Alexander F. , Gillet Philippe
Published: June 2015

Significance

Ice-VII and ice-X phases are the most stable forms of ice at high temperature and extreme pressures, typical of the interiors of satellites and planets. The phase transition between them is a prototypical case of quantum-driven phenomenon, as it can be described as a quantum delocalization of protons in the middle of O–O distances. In this study, we investigate the effect of ions on such quantum effects. We show that the presence of ions significantly modifies the fundamental H-bond properties of water ices. This finding could challenge our present description of the physics of ice bodies, essentially based on the assumption of the properties of pure ice under high pressure.
Pathways to dewetting in hydrophobic confinement
Authors: Remsing Richard C. , Xi Erte , Vembanur Srivathsan , Sharma Sumit , Debenedetti Pablo G. , Garde Shekhar , Patel Amish J.
Published: June 2015

Significance

Dewetting in hydrophobic confinement plays an important role in diverse phenomena, ranging from protein folding and assembly, to the heterogeneous nucleation of vapor bubbles and superhydrophobicity. Using molecular simulations, we find that dewetting proceeds through the formation of isolated cavities adjacent to one of the confining surfaces. These isolated cavities are stabilized by enhanced water density fluctuations, and their growth is uphill in free energy. Upon growing to a certain size, the isolated cavities transition abruptly into supercritical vapor tubes that span the confined region, and grow spontaneously. Consequently, this nonclassical pathway results in lower free energy barriers than anticipated by macroscopic theory, with important implications for the kinetics of dewetting and hence for water-mediated self-assembly.
Even with nonnative interactions, the updated folding transition states of the homologs Proteins G & L are extensive and similar
Authors: Baxa Michael C. , Yu Wookyung , Adhikari Aashish N. , Ge Liang , Xia Zhen , Zhou Ruhong , Freed Karl F. , Sosnick Tobin R.
Published: June 2015

Significance

An outstanding issue in protein science is identifying the relationship between sequence and folding, e.g., do sequences having similar structures have similar folding pathways? The homologs Proteins G & L have been cited as a primary example where sequence variations dramatically affect folding dynamics. However, our new results indicate that the homologs have similar folding behavior. At the highest point on the reaction surface, the pathways converge to similar ensembles. These findings are distinct from descriptions based on the widely used mutational ϕ analysis, partly due to nonnative behavior. Our study emphasizes that significant challenges remain both in characterizing and predicting transition state ensembles even for relatively simple proteins whose folding behavior is believed to be well understood.
Statistical learning and selective inference
Authors: Taylor Jonathan , Tibshirani Robert J.
Published: June 2015

Significance

Most statistical analyses involve some kind of ‟selection”—searching through the data for the strongest associations. Measuring the strength of the resulting associations is a challenging task, because one must account for the effects of the selection. There are some new tools in selective inference for this task, and we illustrate their use in forward stepwise regression, the lasso, and principal components analysis.
Genetic and epigenetic architecture of sex-biased expression in the jewel wasps
Nasonia vitripennis
and
giraulti
Authors: Wang Xu , Werren John H. , Clark Andrew G.
Published: June 2015

Significance

This paper provides a comprehensive analysis of sex differential gene expression in haplodiploid jewel wasps. Between two closely related species, 75% of genes display differential expression, despite males having half the genetic complement of females, with no sex chromosomes. These differences are not directly mediated by sex-specific methylation because almost no sex differences in methylation were observed. Genes with sex-specific expression show low frequency of methylation. However, the majority of female-biased genes are methylated (in both sexes), whereas male-biased ones are mostly nonmethylated in either sex. We conclude that female-biased genes are more likely to be recruited from conserved methylated genes over evolutionary time, whereas most male-biased genes are from genes after recent duplication events that are not methylated.
Language and identity of migrants
Authors: Ladilova Anna
Published: June 2015

Collective identity construction as a discursive action is highly dependent on language use. Migration settings offer a wide range of linguistic repertoires to fall back upon in order to mark identity. While the ‘majority’ language is usually neutral in this sense, the use of the ‘minority’ or the heritage language, defined as a language “other than the dominant language (or languages) in a given social context” (Kelleher 2010, 1), can act as a specific means of identity construction. Moreover, the heritage language acts as a vehicle for transmission of collective memory which is also central in the process and will thus be discussed in this paper. These questions will be analysed by drawing on the results of an empirical study carried out in 2010 in Volga German communities in Argentina.
Intonation unit boundaries and the storage of bigrams
Authors: Wahl Alexander
Published: June 2015

Much recent work on language and cognition has examined the psychological status of collocations/formulas/multi-word expressions as mentally stored units. These studies have used a variety of statistical metrics to quantify the degree of strength or association of these sequences, and then they have correlated these strengths with particular behavioral effects that evidence mental storage. However, the relationship between intonational prosody and storage of collocations has received little attention. Through a corpus-based approach, this study examines the hypothesis that boundaries between successive intonation units avoid splitting word bigrams that exhibit high statistical association, with such high association taken to be an index of mental storage of these bigrams. Conversely, bigrams exhibiting lower statistical association ought to be more likely to be split by intonation unit boundaries under this hypothesis.
Family poultry and food and nutrition security.
Authors: Bruyn J. de , Wong J. , Bagnol B. , Pengelly B. , Alders R.
Published: June 2015

Family poultry production, which encompasses both extensive and small-scale intensive management systems, is practiced by many households in low-income food-deficit countries. Despite low production levels and potentially high losses due to disease, predation and theft, scavenging systems offer the advantage of requiring minimal land, labour and capital inputs. Human undernutrition remains a major public health challenge globally, contributing to over 3 million preventable maternal and child deaths each year. Animal source foods, including poultry (meat and organs) and eggs, can provide high-quality protein and micronutrients in bioavailable forms which, even in small quantities, substantially increase the nutrient adequacy of traditional diets based on staple crops. Women are recognized as key players in family poultry production systems and successful engagement with this sector should incorporate gender-sensitive approaches. It has been shown that agricultural interventions which target women are more likely to lead to positive nutritional outcomes. A multi-disciplinary research approach, multi-sectoral involvement within government institutions and the implementation of policies which target smallholder farmers is needed in order to maximize the potential impact of improvements to family poultry systems on food and nutritional security.
Identification of phenotypically and functionally heterogeneous mouse mucosal-associated invariant T cells using MR1 tetramers
Authors: Rahimpour Azad , Koay Hui Fern , Enders Anselm , Clanchy Rhiannon , Eckle Sidonia B.G. , Meehan Bronwyn , Chen Zhenjun , Whittle Belinda , Liu Ligong , Fairlie David P. , Goodnow Chris C. , McCluskey James , Rossjohn Jamie , Uldrich Adam P. , Pellicci Daniel G. , Godfrey Dale I.
Published: June 2015

Studies on the biology of mucosal-associated invariant T cells (MAIT cells) in mice have been hampered by a lack of specific reagents. Using MR1-antigen (Ag) tetramers that specifically bind to the MR1-restricted MAIT T cell receptors (TCRs), we demonstrate that MAIT cells are detectable in a broad range of tissues in C57BL/6 and BALB/c mice. These cells include CD4−CD8−, CD4−CD8+, and CD4+CD8− subsets, and their frequency varies in a tissue- and strain-specific manner. Mouse MAIT cells have a CD44hiCD62Llo memory phenotype and produce high levels of IL-17A, whereas other cytokines, including IFN-γ, IL-4, IL-10, IL-13, and GM-CSF, are produced at low to moderate levels. Consistent with high IL-17A production, most MAIT cells express high levels of retinoic acid–related orphan receptor γt (RORγt), whereas RORγtlo MAIT cells predominantly express T-bet and produce IFN-γ. Most MAIT cells express the promyelocytic leukemia zinc finger (PLZF) transcription factor, and their development is largely PLZF dependent. These observations contrast with previous reports that MAIT cells from Vα19 TCR transgenic mice are PLZF− and express a naive CD44lo phenotype. Accordingly, MAIT cells from normal mice more closely resemble human MAIT cells than previously appreciated, and this provides the foundation for further investigations of these cells in health and disease.
Endothelial CD99 signals through soluble adenylyl cyclase and PKA to regulate leukocyte transendothelial migration
Authors: Watson Richard L. , Buck Jochen , Levin Lonny R. , Winger Ryan C. , Wang Jing , Arase Hisashi , Muller William A.
Published: June 2015

CD99 is a critical regulator of leukocyte transendothelial migration (TEM). How CD99 signals during this process remains unknown. We show that during TEM, endothelial cell (EC) CD99 activates protein kinase A (PKA) via a signaling complex formed with the lysine-rich juxtamembrane cytoplasmic tail of CD99, the A-kinase anchoring protein ezrin, and soluble adenylyl cyclase (sAC). PKA then stimulates membrane trafficking from the lateral border recycling compartment to sites of TEM, facilitating the passage of leukocytes across the endothelium. Pharmacologic or genetic inhibition of EC sAC or PKA, like CD99 blockade, arrests neutrophils and monocytes partway through EC junctions, in vitro and in vivo, without affecting leukocyte adhesion or the expression of relevant cellular adhesion molecules. This is the first description of the CD99 signaling pathway in TEM as well as the first demonstration of a role for sAC in leukocyte TEM.
Bandage: interactive visualization of de novo genome assemblies
Authors: Wick Ryan R. , Schultz Mark B. , Zobel Justin , Holt Kathryn E.
Published: June 2015

Summary: Although de novo assembly graphs contain assembled contigs (nodes), the connections between those contigs (edges) are difficult for users to access. Bandage (a Bioinformatics Application for Navigating De novo Assembly Graphs Easily) is a tool for visualizing assembly graphs with connections. Users can zoom in to specific areas of the graph and interact with it by moving nodes, adding labels, changing colors and extracting sequences. BLAST searches can be performed within the Bandage graphical user interface and the hits are displayed as highlights in the graph. By displaying connections between contigs, Bandage presents new possibilities for analyzing de novo assemblies that are not possible through investigation of contigs alone.

Availability and implementation: Source code and binaries are freely available at https://github.com/rrwick/Bandage. Bandage is implemented in C++ and supported on Linux, OS X and Windows. A full feature list and screenshots are available at http://rrwick.github.io/Bandage.

Contact:  rrwick@gmail.com

Supplementary information  :  Supplementary data are available at Bioinformatics online.
French Visions of Empire: Contesting British Power in India after the Seven Years War
Authors: Margerison Kenneth
Published: June 2015

Britain’s decisive victory in the Seven Years War destroyed much of the French empire in North America and seriously weakened the French position in India, resulting in the demise of the authority of the Compagnie des Indes in 1769. Despite the devastating results of defeat, the French royal government began laying plans to challenge Britain’s global power. The French position in India, however, was quite weak. Pondichéry, the principal French establishment, had been destroyed during the war, and France had only a small armed force on the subcontinent after 1763. However, the colonial officials in India assured the ministry that many important Indian princes chafed under the tyrannical authority of the British East India Company and would eagerly join—and, some argued, even pay for—a French invasion force in order to weaken or destroy that power. The prospect of a colonial uprising in North America added to the French hopes of success. The governor, Jean Law de Lauriston, insisted that France increase its military force and rebuild the fortifications at Pondichéry to demonstrate French power to the Indian rulers. The ministry, however, did not bolster its military presence in India, preferring to believe that the princes would bear the brunt of the expenses and fighting in India while France devoted its resources to the North American conflict. In the end this vision of a restored French presence in India failed to materialise because the Indian rulers saw little evidence that France would undertake a meaningful attack against British authority in India.
The Association of Demodex with Chalazia: A Histopathologic Study of the Eyelid
Authors: Schear Matthew J. , Milman Tatyana , Steiner Tehilla , Shih Carolyn , Udell Ira J. , Steiner Anne
Published: June 2015

Purpose:

To investigate the association of Demodex with chalazia and to describe the associated histopathologic changes in the eyelid tissue.

Methods:

In a retrospective histopathologic case–control study, 78 ectropion/entropion repair eyelid wedge resections were examined. Serial sections were obtained on formalin-fixed, paraffin-embedded tissues, stained with hematoxylin-eosin and studied by light microscopy. Thirty-eight patient specimens had evidence of chalazia and 40 did not. The main outcome measures included quantification of total eyelid hair follicles, meibomian glands, Demodex folliculorum and Demodex brevis; determining the presence of lipogranulomatous and non-lipogranulomatous inflammation, hair follicle and meibomian gland duct dilatation and hyperkeratinization, and meibomian gland acinar dilation, keratinization, and atrophy.

Results:

There was a significantly greater mean number of D. folliculorum in biopsies with chalazia, when compared with biopsies without chalazia (5.55 vs. 2.68, p = 0.044). The presence of D. folliculorum was strongly associated with hair follicle duct dilatation and hyperkeratinization and with perifollicular nongranulomatous inflammation (p = 0.00). Hair follicle duct dilatation, hyperkeratinization, and perifollicular inflammation were also independently associated with chalazia (p = 0.040 and 0.031, respectively). D. brevis was observed only in meibomian glands with chalazia (mean = 0.342), but this finding did not reach statistical significance; p= 0.068.

Conclusion:

While the authors cannot establish causality between Demodex and chalazia, these findings suggest that D. folliculorum indirectly may be involved in the pathogenesis of chalazia via its effect on the anterior eyelid margin.
The Relationships Among Perceived Patients' Safety Culture, Intention to Report Errors, and Leader Coaching Behavior of Nurses in Korea: A Pilot Study
Authors: Ko YuKyung , Yu Soyoung
Published: June 2015

Objectives

This study was undertaken to explore the correlations among nurses' perceptions of patient safety culture, their intention to report errors, and leader coaching behaviors.

Methods

The participants (N = 289) were nurses from 5 Korean hospitals with approximately 300 to 500 beds each. Sociodemographic variables, patient safety culture, intention to report errors, and coaching behavior were measured using self-report instruments. Data were analyzed using descriptive statistics, Pearson correlation coefficient, the t test, and the Mann-Whitney U test.

Results

Nurses' perceptions of patient safety culture and their intention to report errors showed significant differences between groups of nurses who rated their leaders as high-performing or low-performing coaches. Perceived coaching behavior showed a significant, positive correlation with patient safety culture and intention to report errors, i.e., as nurses' perceptions of coaching behaviors increased, so did their ratings of patient safety culture and error reporting.

Conclusions

There is a need in health care settings for coaching by nurse managers to provide quality nursing care and thus improve patient safety. Programs that are systematically developed and implemented to enhance the coaching behaviors of nurse managers are crucial to the improvement of patient safety and nursing care. Moreover, a systematic analysis of the causes of malpractice, as opposed to a focus on the punitive consequences of errors, could increase error reporting and therefore promote a culture in which a higher level of patient safety can thrive.