bluuebunny/crossref_metadata_2025 huggingface dataset:
Zebrafish (Danio rerio) as a possible bioindicator of epigenetic factors present in drinking water that may affect reproductive function: is chorion an issue?
Authors: Martinez-Sales M. , García-Ximénez F. , Espinós FJ.
Published: March 2014

Emerging organic contaminants have been monitored in stream waters, raw and finished waters and wastewater effluents. Most of these contaminants, such as epigenetic substances, have been detected at very low levels. Unfortunately, their complete monitoring and/or removal are very difficult, given the increasing presence of new contaminants and due to analytical and economic considerations. For this reason, bioindicators are used as an alternative to monitor their presence. To this end, zebrafish is being used to assess certain contaminants in water quality studies.

As our long-term aim is to determine if zebrafish (Danio rerio) can be used to detect environmental epigenetic factors in drinking waters with effects on human reproduction, an initial question is whether the chorion could interfere with the possible action of epigenetic factors in two reproductive events: genital ridge formation and migration of the primordial germ cells (PGCs) to these genital ridges.

In the first experiment, we attempted to partially degrade the chorion of mid blastula transition (MBT) embryos with pronase, with acceptable survival rates at 5 days post fertilisation (dpf), with the group exposed for 15 min giving the best survival results. As denuded early embryos require a specific culture medium, in the next experiment embryo survival was evaluated when they were cultured up to 5 dpf in drinking waters from six different sources. Results showed a negative effect on embryo survival at 5 dpf from several waters but not in others, thus distorting the survival outcomes. These results suggest using embryos with the chorion intact from the outset when drinking waters from different sources are to be tested.
THE SOCIAL CONTEXT OF HOBBES'S POLITICAL THOUGHT
Authors: HAMILTON JAMES J.
Published: March 2014

The social context of Hobbes's political thought is ripe for reassessment in light of advances in the social history of seventeenth-century England in the past half-century. The evidence does not support C. B. Macpherson's claim that England had a “possessive market society” which became the social model for Hobbes's political theory, nor the case that Hobbes was a bourgeois ideologist. A new examination of his social theory, his social identity, his social prejudices and his understanding of what we today call social class instead produces a picture of an intellectual of the “middle sort” with strong aristocratic, pro-court sentiments. A clearer understanding of his social views would probably have prevented the current controversy over his political sentiments or channeled it in a different direction. The issues make a strong case for more social contextualization at the macro level of analysis in intellectual history.
Eine Einführung in Impulskontrollstörungen bei Morbus Parkinson
Authors: Heldmann Marcus , Al-Khaled Mohamed , Hagenah Johann , Münte Thomas F.
Published: March 2014

Impulskontrollstörungen werden bei Parkinson-Patienten vor allem im Zusammenhang mit der Medikation von Dopaminagonisten beobachtet und treten bei entsprechender Medikation in bis zu 17 % der Behandelten auf. Diese Störungen umfassen pathologisches Spielen, pathologisches Kaufen, Hypersexualität und die Binge-Eating Störung. Mit Hilfe bildgebender Verfahren konnte gezeigt werden, dass Dopaminagonisten zu einer Abschwächung der Reaktivität des Belohnungssystems auf Belohnungsreize führen. Ferner konnten bedeutsame Unterschiede in der Aktivität frontolimbischer Kontrollareale zwischen Parkinsonpatienten mit und ohne Impulskontrollstörungen festgestellt werden. Eine experimentell nachweisbare Konsequenz vermehrter Impulsivität bei Parkinson-Patienten ist eine stärkere Abwertung von in der Zukunft liegenden Gewinnen in so genannten intertemporal choice Aufgaben. Diese Übersicht schließt mit einer Diskussion der praktischen Konsequenzen für das Management von betroffenen Patienten.
Neuronal and Astrocytic Metabolism in a Transgenic Rat Model of Alzheimer's Disease
Authors: Nilsen Linn Hege , Witter Menno P , Sonnewald Ursula
Published: March 2014

Regional hypometabolism of glucose in the brain is a hallmark of Alzheimer's disease (AD). However, little is known about the specific alterations of neuronal and astrocytic metabolism involved in homeostasis of glutamate and GABA in AD. Here, we investigated the effects of amyloid β (Aβ) pathology on neuronal and astrocytic metabolism and glial-neuronal interactions in amino acid neurotransmitter homeostasis in the transgenic McGill-R-Thyl-APP rat model of AD compared with healthy controls at age 15 months. Rats were injected with [1-13C]glucose and [1,2-13C]acetate, and extracts of the hippocampal formation as well as several cortical regions were analyzed using 1H- and 13C nuclear magnetic resonance spectroscopy and high-performance liquid chromatography. Reduced tricarboxylic acid cycle turnover was evident for glutamatergic and GABAergic neurons in hippocampal formation and frontal cortex, and for astrocytes in frontal cortex. Pyruvate carboxylation, which is necessary for de novo synthesis of amino acids, was decreased and affected the level of glutamine in hippocampal formation and those of glutamate, glutamine, GABA, and aspartate in the retrosplenial/cingulate cortex. Metabolic alterations were also detected in the entorhinal cortex. Overall, perturbations in energy- and neurotransmitter homeostasis, mitochondrial astrocytic and neuronal metabolism, and aspects of the glutamate-glutamine cycle were found in McGill-R-Thy1-APP rats.
In vivo Assessment of Human Brainstem Cerebrovascular Function: A Multi-Inversion Time Pulsed Arterial Spin Labelling Study
Authors: Warnert Esther AH , Harris Ashley D , Murphy Kevin , Saxena Neeraj , Tailor Neeta , Jenkins Nigel S , Hall Judith E , Wise Richard G
Published: March 2014

The brainstem (BS) is involved in critical physiologic processes, including control of cardiovascular and respiratory functions. This study implements a multi-inversion time pulsed arterial spin labelling (MTI PASL) imaging sequence that addresses the challenges of BS imaging and aims to measure normal and elevated BS perfusion in healthy volunteers. An initial experiment was performed to obtain the kinetic curve of the label in the BS and consequently to estimate the label arrival times and tissue perfusion in seven participants. A second experiment estimated the BS cerebral vascular reactivity (CVR) to hypercapnia in 10 participants. Images were acquired with a gradient-echo sequence with two spiral interleaves and short echo time (TE = 2.7 ms). Data were analyzed with a two-compartment model, including a tissue and arterial component. In both experiments, perfusion in the BS was significantly lower than in cortical gray matter (repeated measures analysis of variance (RM-ANOVA), P<0.05), which is as expected since the BS consists of gray and white matter, the latter typically showing lower perfusion. The BS CVR found here is comparable to previous reports obtained with positron emission tomography (PET) imaging. Multi-inversion time pulsed ASL in combination with a two-compartment signal model can be used to assess BS perfusion and CVR.
Population Pharmacokinetics of Azithromycin in Whole Blood, Peripheral Blood Mononuclear Cells, and Polymorphonuclear Cells in Healthy Adults
Authors: Sampson MR , Dumitrescu TP , Brouwer KLR , Schmith VD
Published: March 2014

Azithromycin's extensive distribution to proinflammatory cells, including peripheral blood mononuclear cells (PBMCs) and polymorphonuclear cells (PMNs), may be important to its antimicrobial and anti‐inflammatory properties. The need to simultaneously predict azithromycin concentrations in whole blood (“blood”), PBMCs, and PMNs motivated this investigation. A single‐dose study in 20 healthy adults was conducted, and nonlinear mixed effects modeling was used to simultaneously describe azithromycin concentrations in blood, PBMCs, and PMNs (simultaneous PK model). Data were well described by a four‐compartment mamillary model. Apparent central clearance and volume of distribution estimates were 67.3 l/hour and 336 l (interindividual variability of 114 and 122%, respectively). Bootstrapping and visual predictive checks showed adequate model performance. Azithromycin concentrations in blood, PBMCs, and PMNs from external studies of healthy adults and cystic fibrosis patients were within the 5th and 95th percentiles of model simulations. This novel empirical model can be used to predict azithromycin concentrations in blood, PBMCs, and PMNs with different dosing regimens.

CPT Pharmacometrics Syst. Pharmacol. (2014) 3, e103; doi: 10.1038/psp.2013.80; published online 5 March 2014
Hydrogel scaffolds asin vitromodels to study fibroblast activation in wound healing and disease
Authors: Smithmyer Megan E. , Sawicki Lisa A. , Kloxin April M.
Published: March 2014

Hydrogels offer controllable and well-definedin vitroplatforms to study the role of the fibroblast in wound healing and fibrosis.
The chemical origin and catalytic activity of coinage metals: from oxidation to dehydrogenation
Authors: Syu Cih-Ying , Yang Hao-Wen , Hsu Fu-Hsing , Wang Jeng-Han
Published: March 2014

Electronegative adspecies on inactive coinage metals can dramatically enhance their catalytic activity for oxidation as well as dehydrogenation reactions.
Effects of crystalline phase and morphology on the visible light photocatalytic H2-production activity of CdS nanocrystals
Authors: Lang Di , Xiang Quanjun , Qiu Guohong , Feng Xionghan , Liu Fan
Published: March 2014

Optimized multi-armed CdS nanorods with a high percentage of wurtzite, prepared by a simple solvothermal route, exhibited high visible-light photocatalytic H2-production performance.
The use of climatologies and Bayesian models to link observations to outcomes; an example from the Torres Strait
Authors: Bainbridge Scott , Berkelmans Ray
Published: March 2014

In response to coral bleaching in the Torres Strait in 2009–10 an ocean monitoring program was established. This included a bleaching early warning system that uses real time data, climatologies and Bayesian models to deliver risk indicators linked to management outcomes.
Strategies towards the synthesis of calyciphylline A-type Daphniphyllum alkaloids
Authors: Kang Baldip , Jakubec Pavol , Dixon Darren J.
Published: March 2014

The structurally unique calyciphylline A-type Daphniphyllum alkaloids have recently attracted the interest of natural product synthesis groups, due to the challenge posed by the complex structural framework. Recently, several noteworthy core syntheses were reported using a variety of novel synthetic strategies, which include intramolecular Michael addition, Pd-catalysis, cycloaddition and Mannich-type reactions.
Enantio- and chemoselective Brønsted-acid/Mg(nBu)2 catalysed reduction of α-keto esters with catecholborane
Authors: Enders Dieter , Stöckel Bianca A. , Rembiak Andreas
Published: March 2014

The first enantio- and chemoselective Brønsted-acid catalysed reduction of α-keto esters with catecholborane has been developed.
Electrohydrodynamic removal of non-specific colloidal adsorption at electrode interfaces
Authors: Rauf Sakandar , Shiddiky Muhammad J. A. , Trau Matt
Published: March 2014

This communication reports the use of an electrohydrodynamic surface shear force to selectively manipulate colloid–surface interactions. We demonstrate the selection of strongly (specifically) bound biomolecular-functionalized colloidal beads over more weakly (non-specifically) bound beads.
Electron transport characteristics in nanosegregated columnar phases of perylene tetracarboxylic bisimide derivatives bearing oligosiloxane chains
Authors: Funahashi Masahiro , Sonoda Akinari
Published: March 2014

An electron transport process in columnar phases of perylene tetracarboxylic bisimide derivatives is analyzed based on the one-dimensional Gaussian disorder model.
Self-assembly and optical properties of a porphyrin-based amphiphile
Authors: Dong Ruijiao , Bo Yang , Tong Gangsheng , Zhou Yongfeng , Zhu Xinyuan , Lu Yunfeng
Published: March 2014

A porphyrin-based amphiphile exhibits various self-assembled morphologies and distinct optical properties in different solvents.
Hierarchical MoS2 nanosheet/active carbon fiber cloth as a binder-free and free-standing anode for lithium-ion batteries
Authors: Wang Chao , Wan Wang , Huang Yunhui , Chen Jitao , Zhou Heng Hui , Zhang Xin Xiang
Published: March 2014

The hierarchical MoS2 nanosheet/ACF cloth is used as a binder-free and free-standing anode for lithium-ion batteries and shows excellent electrochemical performance.
Peptide-templated gold nanoclusters as a novel label-free biosensor for the detection of protease activity
Authors: Gu Yi , Wen Qian , Kuang Yongqing , Tang Lijuan , Jiang Jianhui
Published: March 2014

A novel label-free fluorescent biosensor platform has been developed for protease activity assay using peptide-templated gold nanoclusters (AuNCs).
Morphology, mechanical and dielectric properties, and rheological behavior of EAGMA toughened microcellular PEI–EAGMA foam
Authors: Lei Yajie , Liu Tao , Chen Zhenglei , Lu Ai , Wang Xianzhong , Zhao Xiuli
Published: March 2014

EAGMA plays an important role in the microcellular structure formation and had an excellent toughening effect on the PEI–EAGMA system.
New rearranged limonoids from Walsura cochinchinensis
Authors: Han Mei-Ling , Shen Yu , Leng Ying , Zhang Hua , Yue Jian-Min
Published: March 2014

This paper describes the discovery of a rare class of rearranged limonoids from Walsura cochinchinensis.
Saddle-splay screening and chiral symmetry breaking in toroidal nematics
Authors: Koning Vinzenz , van Zuiden Benjamin C. , Kamien Randall D. , Vitelli Vincenzo
Published: March 2014

A structural transition between achiral (a) and chiral (b and c) nematic toroids occurs upon changing their slenderness or elastic constants.
Band-gap tuning of lead halide perovskites using a sequential deposition process
Authors: Kulkarni Sneha A. , Baikie Tom , Boix Pablo P. , Yantara Natalia , Mathews Nripan , Mhaisalkar Subodh
Published: March 2014

Demonstration of band-gap tuning of mixed anion lead halide perovskites (MAPb(I1−xBrx)2 (0 ≤ x ≤ 1)) by means of a sequential deposition process.
Double junction polymer solar cells
Authors: Adebanjo Olusegun , Vaagensmith Bjorn , Qiao Qiquan
Published: March 2014

Tandem polymer solar cells can achieve significantly higher efficiencies by reducing the absorption and thermalization loss.
Photochromic LC–polymer composites containing azobenzene chromophores with thermally stable Z-isomers
Authors: Bobrovsky Alexey , Shibaev Valery , Cigl Martin , Hamplová Vĕra , Hampl František , Elyashevitch Galina
Published: March 2014

LC composites with photoswitchable dichroism and birefringence, based on porous polyethylene filled with an LC mixture containing azobenzene chromophores, were elaborated.
Structure and fluorescence properties of ternary aluminosilicate glasses doped with samarium and europium
Authors: Herrmann Andreas , Kuhn Stefan , Tiegel Mirko , Rüssel Christian , Körner Jörg , Klöpfel Diethard , Hein Joachim , Kaluza Malte C.
Published: March 2014

A red fluorescent Sm3+-doped aluminosilicate glass under UV excitation. Inset: Dependence of the Sm3+fluorescence lifetime on the refractive indexne(upper left) and the influence of the network modifier on the glass structure (lower left).
Numerical study on a canonized Hamiltonian system representing reduced magnetohydrodynamics and its comparison with two-dimensional Euler system
Authors: Kaneko Yuta , Yoshida Zensho
Published: March 2014

Introducing a Clebsch-like parameterization, we have formulated a canonical Hamiltonian system on a symplectic leaf of reduced magnetohydrodynamics. An interesting structure of the equations is in that the Lorentz-force, which is a quadratic nonlinear term in the conventional formulation, appears as a linear term −ΔQ, just representing the current density (Q is a Clebsch variable, and Δ is the two-dimensional Laplacian); omitting this term reduces the system into the two-dimensional Euler vorticity equation of a neutral fluid. A heuristic estimate shows that current sheets grow exponentially (even in a fully nonlinear regime) together with the action variable P that is conjugate to Q. By numerical simulation, the predicted behavior of the canonical variables, yielding exponential growth of current sheets, has been demonstrated.
Lift and wakes of flying snakes
Authors: Krishnan Anush , Socha John J. , Vlachos Pavlos P. , Barba L. A.
Published: March 2014

Flying snakes use a unique method of aerial locomotion: they jump from tree branches, flatten their bodies, and undulate through the air to produce a glide. The shape of their body cross-section during the glide plays an important role in generating lift. This paper presents a computational investigation of the aerodynamics of the cross-sectional shape. Two-dimensional simulations of incompressible flow past the anatomically correct cross-section of the species Chrysopelea paradisi show that a significant enhancement in lift appears at a 35° angle of attack, above Reynolds numbers 2000. Previous experiments on physical models also obtained an increased lift, at the same angle of attack. The flow is inherently three-dimensional in physical experiments, due to fluid instabilities, and it is thus intriguing that the enhanced lift also appears in the two-dimensional simulations. The simulations point to the lift enhancement arising from the early separation of the boundary layer on the dorsal surface of the snake profile, without stall. The separated shear layer rolls up and interacts with secondary vorticity in the near-wake, inducing the primary vortex to remain closer to the body and thus cause enhanced suction, resulting in higher lift.
Nanopipette combined with quartz tuning fork-atomic force microscope for force spectroscopy/microscopy and liquid delivery-based nanofabrication
Authors: An Sangmin , Lee Kunyoung , Kim Bongsu , Noh Haneol , Kim Jongwoo , Kwon Soyoung , Lee Manhee , Hong Mun-Heon , Jhe Wonho
Published: March 2014

This paper introduces a nanopipette combined with a quartz tuning fork-atomic force microscope system (nanopipette/QTF-AFM), and describes experimental and theoretical investigations of the nanoscale materials used. The system offers several advantages over conventional cantilever-based AFM and QTF-AFM systems, including simple control of the quality factor based on the contact position of the QTF, easy variation of the effective tip diameter, electrical detection, on-demand delivery and patterning of various solutions, and in situ surface characterization after patterning. This tool enables nanoscale liquid delivery and nanofabrication processes without damaging the apex of the tip in various environments, and also offers force spectroscopy and microscopy capabilities.
A microscopic model of the Tian-Calvet microcalorimeter, cell design for a faster response, and measurement by a continuous procedure
Authors: Kobayashi Y. , Wang F. , Li Q. X. , Wang D. Z.
Published: March 2014

The transient heat conduction equation was used as the microscopic model of the Tian-Calvet microcalorimeter. It was verified by comparing simulated and experimental calorimetric curves and used to guide sample cell design for a faster response time, for which it gave the guidelines to minimize the heat flow distance and use a heat flux that is uniform and onto the whole face of the thermopile sensor. The resulting sample cell was disc-shaped with the sample powder placed in it as a thin 0.2 mm layer on a stainless steel base with a wall thickness of 0.5 mm that covered the whole face of the thermopile on which it was placed. The rise time of the heat response curve to a step change in sample temperature, which is the response time for measuring the differential heat released, was 45 s. The response curve from a gas dose returned to the baseline within 400 s, which is the time needed to measure the integrated heat in a pulsed dosage. The accuracy of the heats measured by the calorimeter was verified by comparison with data in the literature on the adsorption of ethanol and ammonia on HZSM-5 and adsorption of methanol and ammonia on SAPO-34. The differential heat of methanol adsorption on SAPO-34 at 333 K and ammonia adsorption on HZSM-5 at 423 K were measured by both the conventional discontinuous procedure and a new continuous procedure. In the continuous procedure, gas was continuously dosed at a very slow flow rate that was kept slow enough for the gas and adsorbate to reach quasi-equilibrium. The continuous procedure has the advantages of high resolution results and a simpler experimental procedure, and a calorimetric curve could be measured within 3 h.
Self-interaction corrections in density functional theory
Authors: Tsuneda Takao , Hirao Kimihiko
Published: March 2014

Self-interaction corrections for Kohn-Sham density functional theory are reviewed for their physical meanings, formulations, and applications. The self-interaction corrections get rid of the self-interaction error, which is the sum of the Coulomb and exchange self-interactions that remains because of the use of an approximate exchange functional. The most frequently used self-interaction correction is the Perdew-Zunger correction. However, this correction leads to instabilities in the electronic state calculations of molecules. To avoid these instabilities, several self-interaction corrections have been developed on the basis of the characteristic behaviors of self-interacting electrons, which have no two-electron interactions. These include the von Weizsäcker kinetic energy and long-range (far-from-nucleus) asymptotic correction. Applications of self-interaction corrections have shown that the self-interaction error has a serious effect on the states of core electrons, but it has a smaller than expected effect on valence electrons. This finding is supported by the fact that the distribution of self-interacting electrons indicates that they are near atomic nuclei rather than in chemical bonds.
Orientation dependent electro-optic properties of K0.95Li0.05Ta0.41Nb0.59O3 single crystal: Experiment and simulation
Authors: Li J. , Li Y. , Zhou Z. Z. , Guo R. Y. , Bhalla A. S.
Published: March 2014

Large low frequency linear electro-optic responses of K0.95Li0.05Ta0.41Nb0.59O3 single crystal were determined at the laser wavelength of 632.8 nm: γ33 = 223.7 pm/V, γ13 = −35.2 pm/V, and γ51 = 11060 pm/V by using the autoscanning Mach-Zehnder interferometer technique and modified AC modulating method, respectively. Crystal orientation dependent electro-optic properties have been simulated based on the non-zero matrix of experimental measured electro-optic coefficients. The simulation results demonstrate the maximum electro-optic coefficient occurred at 54.53° away [001] direction is 8548.3 pm/V. In addition to the high ferroelectric phase transition temperature (∼430 K), good piezoelectric properties and high optical crystal quality, the ultrahigh electro-optic performance of K0.95Li0.05Ta0.41Nb0.59O3 single crystal forecasts its outstanding potential in various electro-mechanical-optical coupled applications.
Particle-in-cell simulation for parametric decays of a circularly polarized Alfvén wave in relativistic thermal electron-positron plasma
Authors: López Rodrigo A. , Muñoz Víctor , Viñas Adolfo F. , Alejandro Valdivia J.
Published: March 2014

Parametric decays of a left-handed circularly polarized Alfvén wave propagating along a constant background magnetic field in a relativistic thermal electron-positron plasma are studied by means of a one dimensional relativistic particle-in-cell simulation. Relativistic effects are included in the Lorentz equation for the momentum of the particles and in their thermal motion, by considering a Maxwell-Jüttner velocity distribution function for the initial condition. In the linear stage of the simulation, we find many instabilities that match the predictions of relativistic fluid theory. In general, the growth rates of the instabilities increase as the pump wave amplitude is increased, and decrease with a raise in the plasma temperatures. We have confirmed that for very high temperatures the Alfvén branch is suppressed, consistent with analytical calculations.
Self-aligned Ni-GaSb source/drain junctions for GaSb p-channel metal-oxide-semiconductor field-effect transistors
Authors: Yokoyama Masafumi , Nishi Koichi , Kim Sanghyeon , Yokoyama Haruki , Takenaka Mitsuru , Takagi Shinichi
Published: March 2014

We demonstrate self-aligned Ni-GaSb alloy source/drain (S/D) junctions for GaSb p-channel metal-oxide-semiconductor field-effect transistors (p-MOSFETs). Ni-GaSb alloys are used as self-aligned S/D junctions for GaSb p-MOSFETs formed with low-temperature annealing at 250 °C. Low-temperature process is preferred to avoid temperature-induced problems, because GaSb MOS gate stacks can show better MOS interface properties with lowering process temperature. This low-temperature S/D formation allowed us to realize the normal transistor operation of GaSb p-MOSFETs. Ni-GaSb alloy junctions can show the low contact resistivity with shallow junction depth. Self-aligned Ni-GaSb alloy S/D junctions can be an appropriate S/D junction technology for GaSb p-MOSFETs.
Intracavity quartz-enhanced photoacoustic sensor
Authors: Borri S. , Patimisco P. , Galli I. , Mazzotti D. , Giusfredi G. , Akikusa N. , Yamanishi M. , Scamarcio G. , De Natale P. , Spagnolo V.
Published: March 2014

We report on a spectroscopic technique named intracavity quartz-enhanced photoacoustic spectroscopy (I-QEPAS) employed for sensitive trace-gas detection in the mid-infrared spectral region. It is based on a combination of QEPAS with a buildup optical cavity. The sensor includes a distributed feedback quantum cascade laser emitting at 4.33 μm. We achieved a laser optical power buildup factor of ∼500, which corresponds to an intracavity laser power of ∼0.75 W. CO2 has been selected as the target molecule for the I-QEPAS demonstration. We achieved a detection sensitivity of 300 parts per trillion for 4 s integration time, corresponding to a noise equivalent absorption coefficient of 1.4 × 10−8 cm−1 and a normalized noise-equivalent absorption of 3.2 × 10−10 W cm−1 Hz−1/2.
Control of the magnetic in-plane anisotropy in off-stoichiometric NiMnSb
Authors: Gerhard F. , Schumacher C. , Gould C. , Molenkamp L. W.
Published: March 2014

NiMnSb is a ferromagnetic half-metal which, because of its rich anisotropy and very low Gilbert damping, is a promising candidate for applications in information technologies. We have investigated the in-plane anisotropy properties of thin, molecular beam epitaxy-grown NiMnSb films as a function of their Mn concentration. Using ferromagnetic resonance to determine the uniaxial and four-fold anisotropy fields, 2KUMs and 2K1Ms, we find that a variation in composition can change the strength of the four-fold anisotropy by more than an order of magnitude and cause a complete 90° rotation of the uniaxial anisotropy. This provides valuable flexibility in designing new device geometries.
Thin SiGe virtual substrates for Ge heterostructures integration on silicon
Authors: Cecchi S. , Gatti E. , Chrastina D. , Frigerio J. , Müller Gubler E. , Paul D. J. , Guzzi M. , Isella G.
Published: March 2014

The possibility to reduce the thickness of the SiGe virtual substrate, required for the integration of Ge heterostructures on Si, without heavily affecting the crystal quality is becoming fundamental in several applications. In this work, we present 1 μm thick Si1−xGex buffers (with x > 0.7) having different designs which could be suitable for applications requiring a thin virtual substrate. The rationale is to reduce the lattice mismatch at the interface with the Si substrate by introducing composition steps and/or partial grading. The relatively low growth temperature (475 °C) makes this approach appealing for complementary metal-oxide-semiconductor integration. For all the investigated designs, a reduction of the threading dislocation density compared to constant composition Si1−xGex layers was observed. The best buffer in terms of defects reduction was used as a virtual substrate for the deposition of a Ge/SiGe multiple quantum well structure. Room temperature optical absorption and photoluminescence analysis performed on nominally identical quantum wells grown on both a thick graded virtual substrate and the selected thin buffer demonstrates a comparable optical quality, confirming the effectiveness of the proposed approach.
Structural, optical, and magnetic properties of (Co, Cu)-codoped ZnO films with different Co concentrations
Authors: Xu M. , Yuan H. , You B. , Zhou P. F. , Dong C. J. , Duan M. Y.
Published: March 2014

Zn0.99-xCoxCu0.01O films with different Co concentrations from 0% to 20% were fabricated by a sol-gel method. Moderate Co doping is found to improve the surface uniformity and crystal quality of the films, and causes a redshift of the band edge of Zn(Co,Cu) films. X-ray photoelectron spectroscopy reveals that the introduction of Co ions causes the valence state of Cu to change from +2 to +1; while at Co concentrations lower than 10%, the Co exists in the +2 valence state. Strong blue emission at ∼420 and 440 nm are observed, decreasing with increasing Co concentration, but becoming strong again as the concentration is increased to 20%. Enhanced room-temperature ferromagnetism is observed for the (Co, Cu)-codoped ZnO films at Co concentrations lower than 10%. These interesting magnetic properties are explained based on charge transfer, together with the defect-related model for ferromagnetism.
Transient crystalline superlattice generated by a photoacoustic transducer
Authors: Loether A. , Gao Y. , Chen Z. , DeCamp M. F. , Dufresne E. M. , Walko D. A. , Wen H.
Published: March 2014

Designing an efficient and simple method for modulating the intensity of x-ray radiation on a picosecond time-scale has the potential to produce ultrafast pulses of hard x-rays. In this work, we generate a tunable transient superlattice, in an otherwise perfect crystal, by photoexciting a metal film on a crystalline substrate. The resulting transient strain has amplitudes approaching 1%, wavevectors greater than 0.002 Å−1, and lifetimes approaching 1 ns. This method has the potential to generate isolated picosecond x-ray bursts with scattering efficiencies in excess of 10%.
High non-linear magnetoelectric coefficient in Metglas/PMN-PT laminate composites under zero direct current magnetic bias
Authors: Shen Ying , Gao Junqi , Wang Yaojin , Li Jiefang , Viehland D.
Published: March 2014

The non-linear magnetoelectric (ME) response of Metglas/PMN-PT based sandwiched ME laminate composites has been studied for various thicknesses of the magnetostrictive layer. A significant increase in the non-linear ME coefficient under zero direct current bias was observed with a decreased Metglas thickness ratio for a fixed number of Metglas layers of n = 2. The non-linear ME effect was further improved by driving the laminate at the electromagnetic resonant frequency. The approach offers the potential to modulate low frequency magnetic signals to higher frequencies, where the noise floor is much lower and the signal to noise ratio higher.
Structure of screw dislocation core in Ta at high pressure
Authors: Wang Shaofeng , Jiang Na , Wang Rui , Zhou Ying
Published: March 2014

The core structure and Peierls stress of the 12⟨111⟩{110} screw dislocation in Ta have been investigated theoretically using the modified Peierls–Nabarro theory that takes into account the discreteness effect of crystal. The lattice constants, the elastic properties, and the generalized-stacking-fault energy(γ-surface) under the different pressures have been calculated from the electron density functional theory. The core structure of dislocation is determined by the modified Peierls equation, and the Peierls stress is evaluated from the dislocation energy that varies periodically as dislocation moves. The results show the core width and Peierls stress in Ta are weakly dependent of the pressure up to 100 GPa when the length and stress are measured separately by the Burgers vector b and shear modulus μ. This indicates that core structure is approximately scaling invariant for the screw dislocation in Ta. The scaled plasticity of Ta changes little in high pressure environment.
Deducing critical coupling condition to achieve perfect absorption for thin-film absorbers and identifying key characteristics of absorbing materials needed for perfect absorption
Authors: Long Yongbing , Su Runmei , Wang Qiwen , Shen Liang , Li Bowen , Zheng Wenhao
Published: March 2014

Equations are deduced to describe the critical coupling condition to achieve perfect absorption for the thin-film absorbers of absorbing layer/spacer layer/substrate. By numerically solving these equations, a linear inequality is obtained to describe key characteristics of the absorbing layer needed for perfect absorption at a given wavelength. Guided by this finding, various materials including metals and semiconductors are identified as the absorbing layer to achieve perfect absorption at a randomly chosen wavelength within the visible wavelength range of 400–800 nm. Finally, it is found that absorption in an ultrathin absorbing layer can approach 100% with the use of highly reflective substrate.
Coherent acoustic phonon generation in GaAs1−xBix
Authors: Joshya R. S. , Ptak A. J. , France R. , Mascarenhas A. , Kini R. N.
Published: March 2014

We have used femtosecond laser pulses to generate coherent acoustic phonons in the dilute Bismide alloy, GaAs1−xBix. The observed oscillation periods match well with the oscillation periods calculated using the propagating strain pulse model. We attribute the generation process predominantly to electronic stress due to the absorption of the laser pulse at the surface of the GaAs1−xBix layer. Our initial estimates suggest that the incorporation of Bi in GaAs causes an enhancement of the hydrostatic deformation potential because of the resonant state in the valence band due to isolated Bi impurities.
Grain feeding increases core body temperature of beef cattle
Authors: Jacob R. H. , Surridge V. S. M. , Beatty D. T. , Gardner G. E. , Warner R. D.
Published: March 2014

The core body temperature and post slaughter loin temperatures of steers fed on grass pasture was compared with those of steers fed a grain-based feedlot diet. The feeding treatments were grass for 300 days (Grass), grass for 150 days then feedlot for 150 days (Short Feedlot) and feedlot for 300 days (Long Feedlot). Temperature telemeters were inserted under the peritoneum of the steers and temperature measured at intervals of 1 h for the 300 days, and then at intervals of 1 min for the 48-h period before slaughter. The pH and temperature decline post mortem was also measured. The carcasses of the feedlot steers were heavier and fatter than those from the Grass-fed steers. The core body temperature of the steers from the feedlot treatments was 0.3–0.4°C higher than for the Grass treatment at the time of slaughter. The loin temperature was higher in the feedlot treatments than the Grass treatment at all times measured post mortem as was the temperature at pH 6. Feedlotting can increase the likelihood of ‘high rigor temperature’ conditions of high temperature and low pH occurring in beef carcasses, due to an increase in core body temperature before slaughter, a decrease in the rate of cooling and an increase in the rate of pH decline post mortem. These effects are possibly due to a combination of a direct effect of feed type on body temperature as well as indirect effects on bodyweight and condition score.
Quality improvement initiatives in a case management service: case study
Authors: Davies Deborah J.
Published: March 2014

This article explores the importance of quality practices in underpinning the person-centred approach at a Community Options Program (COP) case management service in northern NSW. The NSW community care sector does not have a statutory excellence body to identify, promote and support improved practices and quality and safety across community services, and therefore the COP provider decided to establish a dedicated role to focus on the quality improvement of its service. The subsequent quality improvement initiatives have included mapping the clients’ journey through the service, identifying areas to standardise practice, and creating service pathways. The clients’ journey was used as the framework to identify where standardised practice was required, and a robust process was implemented to develop over 25 good practice guidelines and tools that addressed the variations in practice and enabled the service pathways to be developed. Prior to trialling the guidelines and tools, staff received education sessions on the anticipated changes to practice, and the practicality and applicability of the guidelines were evaluated at the end of the trials. This information was reviewed and the guidelines were amended accordingly before being rolled out. The guidelines have been in use for over 12 months and have provided the benchmark against which to audit practice, and have resulted in key performance improvements such as an increase in client review rates and a rise in the feedback response rate from clients, with a noticeable shift in the comments about the brokered support worker to acknowledging the role of their case manager. Formalising informal supports for those clients that lived alone also increased, which means these people are less reliant on services and there is a reduced risk of social isolation.
Duality of the murine CD8 compartment
Authors: Genolet Raphaël , Leignadier Julie , Østerås Magne , Farinelli Laurent , Stevenson Brian J. , Luescher Immanuel F.
Published: March 2014

Significance

CD8αβ is expressed on CD8+T cells and can govern their thymic selection, differentiation, and effector functions by inducing Ca2+and nuclear factor of activated T cells (NFAT)-dependent signaling. Conversely, we showed that CD8-independent T cells are signaled in a Ca2+-independent, PI3K-dependent manner. By assessing the physical and functional affinities, signaling, and TCR repertoires of CD8-dependent and -independent T cells, we uncovered correlates between effector functions, their triggering, and the TCR repertoires. We suggest that the docking orientations of TCR–MHC complexes may influence CD8+T-cell signaling and hence their functions. Together, these data argue that signaling events rather than affinity determine CD8 dependency and that the duality of the CD8 compartment may provide the organisms with broader protective immunity.
Anabaptist Approaches to Economics
Authors: Halteman Jim
Published: March 2014

Anabaptists have moved from a position of separatism to a call for faithful interaction with the world even if ambiguities lead to some compromises. Anabaptists can improve the secular order on the margins by joining with non-Christians who share some of their values and by providing in their businesses and consumer practices an alternative model of what faithful stewardship might look like for the Christian. For some, this is movement down a slippery slope to worldliness and for others this increased involvement in existing social institutions is light and salt to the world. This chapter examines the origins of Anabaptist social thought and then follows the trend toward constructive engagement with the social order by examining the work of key Anabaptist thinkers and practitioners from the last century. There is not a unified theoretical approach to economic systems in recent Anabaptist thought, but the historical contextual methodology of American institutionalism may be the most appealing economic school of thought for Anabaptism today.
Interface and Integration in Christian Economics
Authors: Richardson J. David
Published: March 2014

The sad and lonely profile of late twentieth-century Christian scholarship in economics has enjoyed a refreshing makeover in the past two decades. Encouraging new research on the overlapping interface of faith and discipline has attained critical mass and fruitful momentum. This interface includes contributions under the umbrella term “economics of religion,” and somewhat-less-often cited contributions to “positional” and conflict economics, and to institutional mechanism design in law and economics. Beyond interface lies scholarly “integration of faith and discipline” that alters and cross-leavens the foundational frames for analysis in both economics and careful Christian thinking about divine and human nature and society. Such integrative scholarship is still in its infancy. But some of it—in the ethical underpinnings of national economic growth and flourishing, and in the economics of identity and social identification—is attracting noteworthy scholarly attention, as measured by the citation counts used recurrently in this survey.
The Economics of Religious Schism and Switching
Authors: Beard T. Randolph , Ekelund, Jr. Robert B. , Ford George S. , Tollison Robert D.
Published: March 2014

Schism and switching are important in religious markets when strict monopoly or force is not involved. The Protestant Reformation is an important case and may be seen as entry of a new firm into a previously monopolized market. This was essentially rent dissipation. Other cases may involve religious consumers switching to firms that better match their religious preferences. Firms in such a setting make strategic decisions about doctrine and costs imposed on consumers in order to capture segments of the market. Models of schism predict that it will be less prevalent in hierarchical churches where costs are higher, and this appears borne out by data. Models of switching suggest it will be common when brands of churches are numerous and similar, again borne out by data.
Human Nature, Identity, and Motivation
Authors: Menzies Gordon , Hay Donald
Published: March 2014

The question of human nature and identity is not a common preoccupation of economists. The reasons for this are investigated, and the ways in which a theological understanding of human nature might alter economic analysis are explored. The analysis focuses on: preserving a meaning for the term “selfish”; allowing forms of mutual care which are not “gift exchange”; allowing for a personal identity which values altruistic acts of love; modeling the outcome of the conversion experience; and, using the doctrine of creation to place humans over the natural world as stewards but alongside the natural world as fellow-creatures. The Christian account of human nature, identity, and motivation is not only consistent with some recent empirical work, but gives rise to a picture of human persons which other frameworks must presuppose, sometimes without a clear justification.
The allometry between secondary sexual traits and body size is nonlinear among cervids
Authors: Lemaître J. F. , Vanpé C. , Plard F. , Gaillard J. M.
Published: March 2014

Allometric relationships between sexually selected traits and body size have been extensively studied in recent decades. While sexually selected traits generally display positive allometry, a few recent reports have suggested that allometric relationships are not always linear. In male cervids, having both long antlers and large size provides benefits in terms of increased mating success. However, such attributes are costly to grow and maintain, and these costs might constrain antler length from increasing at the same rate as body mass in larger species if the quantity of energy that males can extract from their environment is limiting. We tested for possible nonlinearity in the relationship between antler size and body mass (on a log–log scale) among 31 cervids and found clear deviation from linearity in the allometry of antler length. Antler length increased linearly until a male body mass threshold at approximately 110 kg. Beyond this threshold, antler length did not change with increasing mass. We discuss this evidence of nonlinear allometry in the light of life-history theory and stress the importance of testing for nonlinearity when studying allometric relationships.
Evidence for the circadian gene
period
as a proximate mechanism of protandry in a pollinating fig wasp
Authors: Gu Hai-Feng , Xiao Jin-Hua , Dunn Derek W. , Niu Li-Ming , Wang Bo , Jia Ling-Yi , Huang Da-Wei
Published: March 2014

Protandry in insects is the tendency for adult males to emerge before females and usually results from intra-sexual selection. However, the genetic basis of this common phenomenon is poorly understood. Pollinating fig wasp (Agaonidae) larvae develop in galled flowers within the enclosed inflorescences (‘figs’) of fig trees. Upon emergence, males locate and mate with the still galled females. After mating, males release females from their galls to enable dispersal. Females cannot exit galls or disperse from a fig without male assistance. We sampled male and female
Ceratosolen solmsi
(the pollinator of
Ficus hispida
) every 3 h over a 24 h emergence period, and then measured the expression of five circadian genes:
period
(
per
),
clock
(
clk
),
cycle
(
cyc
),
pigment-dispersing factor
(
pdf
) and
clockwork orange
(
cwo
). We found significant male-biased sexual dimorphism in the expression of all five genes.
per
showed the greatest divergence between the sexes and was the only gene rhythmically expressed. Expression of
per
correlated closely with emergence rates at specific time intervals in both male and female wasps. We suggest that this rhythmical expression of
per
may be a proximate mechanism of protandry in this species.
Cretaceous park of sex determination: sex chromosomes are conserved across iguanas
Authors: Rovatsos Michail , Pokorná Martina , Altmanová Marie , Kratochvíl Lukáš
Published: March 2014

Many poikilothermic vertebrate lineages, especially among amphibians and fishes, possess a rapid turnover of sex chromosomes, while in endotherms there is a notable stability of sex chromosomes. Reptiles in general exhibit variability in sex-determining systems; as typical poikilotherms, they might be expected to have a rapid turnover of sex chromosomes. However, molecular data which would enable the testing of the stability of sex chromosomes are lacking in most lineages. Here, we provide molecular evidence that sex chromosomes are highly conserved across iguanas, one of the most species-rich clade of reptiles. We demonstrate that members of the New World families Iguanidae, Tropiduridae, Leiocephalidae, Phrynosomatidae, Dactyloidae and Crotaphytidae, as well as of the family Opluridae which is restricted to Madagascar, all share homologous sex chromosomes. As our sampling represents the majority of the phylogenetic diversity of iguanas, the origin of iguana sex chromosomes can be traced back in history to the basal splitting of this group which occurred during the Cretaceous period. Iguanas thus show a stability of sex chromosomes comparable to mammals and birds and represent the group with the oldest sex chromosomes currently known among amniotic poikilothermic vertebrates.