bluuebunny/crossref_metadata_2025 huggingface dataset:
Hamiltonian fluid closures of the Vlasov-Ampère equations: From water-bags to N moment models
Authors: Perin M. , Chandre C. , Morrison P. J. , Tassi E.
Published: September 2015

Moment closures of the Vlasov-Ampère system, whereby higher moments are represented as functions of lower moments with the constraint that the resulting fluid system remains Hamiltonian, are investigated by using water-bag theory. The link between the water-bag formalism and fluid models that involve density, fluid velocity, pressure and higher moments is established by introducing suitable thermodynamic variables. The cases of one, two, and three water-bags are treated and their Hamiltonian structures are provided. In each case, we give the associated fluid closures and we discuss their Casimir invariants. We show how the method can be extended to an arbitrary number of fields, i.e., an arbitrary number of water-bags and associated moments. The thermodynamic interpretation of the resulting models is discussed. Finally, a general procedure to derive Hamiltonian N-field fluid models is proposed.
The calculation of thermophysical properties of nickel plasma
Authors: Apfelbaum E. M.
Published: September 2015

The thermophysical properties of Nickel plasma have been calculated for the temperatures 10–60 kK and densities less than 1 g/cm3. These properties are the pressure, internal energy, heat capacity, and the electronic transport coefficients (electrical conductivity, thermal conductivity, and thermal power). The thermodynamic values have been calculated by means of the chemical model, which also allows one to obtain the ionic composition of considered plasma. The composition has been used to calculate the electronic transport coefficients within the relaxation time approximation. The results of the present investigation have been compared with the calculations of other researchers and available data of measurements.
New methodology for the thermal characterization of thermoelectric liquids
Authors: Touati Karim , Depriester Michael , Kuriakose Maju , Hadj Sahraoui Abdelhak
Published: September 2015

A new and accurate method for the thermal characterization of thermoelectric liquids is proposed. The experiment is based on a self-generated voltage due to the Seebeck effect. This voltage is provided by the sample when one of its two faces is thermally excited using a modulated laser. The sample used is tetradodecylammonium nitrate salt/1-octanol mixture, with high Seebeck coefficient. The thermal properties of the used sample (thermal diffusivity, effusivity, and conductivity) are found and compared to those obtained by other photothermal techniques. In addition to this, a study of the electrolyte thermal parameters with the variation of tetradodecylammonium nitrate concentration was also carried out. This new method is promising due to its accuracy and its simplicity.
New sample carrier systems for thermogravimetric analysis under forced flow conditions and their influence on microkinetic results
Authors: Seibel C. , Fieback T. M.
Published: September 2015

For thermogravimetric analysis, it has been shown that, depending on the type of sample container, different kinetic results could be obtained despite regarding the same reaction under constant conditions. This is due to limiting macrokinetic effects which are strongly dependant on the type of sample carrying system. This prompted the need for sample containers which deliver results minimally limited by diffusive mass transport. In this way, two container systems were developed, both characterized by a forced flow stream through a solid, porous bed: one from bottom to top (counter-current flow) and one from top to bottom (co-current flow). Optical test measurements were performed, the results indicating that reaction proceedings are almost fully independent of the geometrical shape of the sample containers. The Boudouard reaction was investigated with a standard crucible and the new developed systems; the reaction rates determined differed significantly, up to a factor of 6.2 at 1373 K.
Simulation study of high-frequency energetic particle driven geodesic acoustic mode
Authors: Wang Hao , Todo Yasushi , Ido Takeshi , Osakabe Masaki
Published: September 2015

High-frequency energetic particle driven geodesic acoustic modes (EGAM) observed in the large helical device plasmas are investigated using a hybrid simulation code for energetic particles and magnetohydrodynamics (MHD). Energetic particle inertia is incorporated in the MHD momentum equation for the simulation where the beam ion density is comparable to the bulk plasma density. Bump-on-tail type beam ion velocity distribution created by slowing down and charge exchange is considered. It is demonstrated that EGAMs have frequencies higher than the geodesic acoustic modes and the dependence on bulk plasma temperature is weak if (1) energetic particle density is comparable to the bulk plasma density and (2) charge exchange time (τcx) is sufficiently shorter than the slowing down time (τs) to create a bump-on-tail type distribution. The frequency of high-frequency EGAM rises as the energetic particle pressure increases under the condition of high energetic particle pressure. The frequency also increases as the energetic particle pitch angle distribution shifts to higher transit frequency. It is found that there are two kinds of particles resonant with EGAM: (1) trapped particles and (2) passing particles with transit frequency close to the mode frequency. The EGAMs investigated in this work are destabilized primarily by the passing particles whose transit frequencies are close to the EGAM frequency.
Quantum funneling in blended multi-band gap core/shell colloidal quantum dot solar cells
Authors: Neo Darren C. J. , Stranks Samuel D. , Eperon Giles E. , Snaith Henry J. , Assender Hazel E. , Watt Andrew A. R.
Published: September 2015

Multi-band gap heterojunction solar cells fabricated from a blend of 1.2 eV and 1.4 eV PbS colloidal quantum dots (CQDs) show poor device performance due to non-radiative recombination. To overcome this, a CdS shell is epitaxially formed around the PbS core using cation exchange. From steady state and transient photoluminescence measurements, we understand the nature of charge transfer between these quantum dots. Photoluminescence decay lifetimes are much longer in the PbS/CdS core/shell blend compared to PbS only, explained by a reduction in non-radiative recombination resulting from CdS surface passivation. PbS/CdS heterojunction devices sustain a higher open-circuit voltage and lower reverse saturation current as compared to PbS-only devices, implying lower recombination rates. Further device performance enhancement is attained by modifying the composition profile of the CQD species in the absorbing layer resulting in a three dimensional quantum cascade structure.
Broadband high-sensitivity current-sensing device utilizing nonlinear magnetoelectric medium and nanocrystalline flux concentrator
Authors: Zhang Jitao , He Wei , Zhang Ming , Zhao Hongmei , Yang Qian , Guo Shuting , Wang Xiaolei , Zheng Xiaowan , Cao Lingzhi
Published: September 2015

A broadband current-sensing device with frequency-conversion mechanism consisting of Terfenol-D/Pb(Zr.Ti)O3 (PZT)/Terfenol-D magnetoelectric laminate and Fe73.5Cu1Nb3Si13.5B9 nanocrystalline flux concentrator is fabricated and characterized. For the purpose of acquiring resonance-enhanced sensitivity within broad bandwidth, a frequency-modulation mechanism is introduced into the presented device through the nonlinearity of field-dependence giant magnetostrictive materials. The presented configuration provides a solution to monitor the weak currents and achieves resonance-enhanced sensitivity of 178.4 mV/A at power-line frequency, which exhibits ∼3.86 times higher than that of direct output at power-line frequency of 50 Hz. Experimental results demonstrate that a weak step-change input current of 1 mA can be clearly distinguished by the output amplitude or phase. This miniature current-sensing device provides a promising application in power-line weak current measurement.
Role of substrate temperature at graphene synthesis in an arc discharge
Authors: Fang Xiuqi , Shashurin Alexey , Keidar Michael
Published: September 2015

The substrate temperature required for synthesis of graphene in an arc discharge plasma was studied. It was shown that an increase of copper substrate temperature up to the melting point leads to an increase in the amount of graphene production and the quality of graphene sheets. Favorable range of substrate temperatures for arc-based graphene synthesis was determined, and it is in a relatively narrow range of about 1210–1340 K.
Random attractor of non-autonomous stochastic Boussinesq lattice system
Authors: Zhao Min , Zhou Shengfan
Published: September 2015

In this paper, we first consider the existence of tempered random attractor for second-order non-autonomous stochastic lattice dynamical system of nonlinear Boussinesq equations effected by time-dependent coupled coefficients and deterministic forces and multiplicative white noise. Then, we establish the upper semicontinuity of random attractors as the intensity of noise approaches zero.
Guiding and collimation of laser-accelerated proton beams using thin foils followed with a hollow plasma channel
Authors: Xiao K. D. , Zhou C. T. , Qiao B. , He X. T.
Published: September 2015

It is proposed that guided and collimated proton acceleration by intense lasers can be achieved using an advanced target—a thin foil followed by a hollow plasma channel. For the advanced target, the laser-accelerated hot electrons can be confined in the hollow channel at the foil rear side, which leads to the formation of transversely localized, Gaussian-distributed sheath electric field and resultantly guiding of proton acceleration. Further, due to the hot electron flow along the channel wall, a strong focusing transverse electric field is induced, taking the place of the original defocusing one driven by hot electron pressure in the case of a purely thin foil target, which results in collimation of proton beams. Two-dimensional particle-in-cell simulations show that collimated proton beams with energy about 20 MeV and nearly half-reduced divergence of 26° are produced at laser intensities 1020 W/cm2 by using the advanced target.
Braking of tearing mode rotation by ferromagnetic conducting walls in tokamaks
Authors: Fitzpatrick Richard
Published: September 2015

An in-depth investigation of the braking of tearing mode rotation in tokamak plasmas via eddy currents induced in external ferromagnetic conducting structures is performed. In general, there is a “forbidden band” of tearing mode rotation frequencies that separates a branch of high-frequency solutions from a branch of low-frequency solutions. When a high-frequency solution crosses the upper boundary of the forbidden band, there is a bifurcation to a low-frequency solution, and vice versa. The bifurcation thresholds predicted by simple torque-balance theory (which takes into account the electromagnetic braking torque acting on the plasma, as well as the plasma viscous restoring torque, but neglects plasma inertia) are found to be essentially the same as those predicted by more complicated time-dependent mode braking theory (which takes inertia into account). Significant ferromagnetism causes otherwise electromagnetically thin conducting structures to become electromagnetically thick and also markedly decreases the critical tearing mode amplitude above which the mode “locks” to the conducting structures (i.e., the high-frequency to low-frequency bifurcation is triggered). On the other hand, if the ferromagnetism becomes too large, then the forbidden band of mode rotation frequencies is suppressed, and the mode frequency consequently varies smoothly and reversibly with the mode amplitude.
Local order and the dependence of magnetization on Co content in V2O5 layered films
Authors: Cezar A. B. , Graff I. L. , Varalda J. , Schreiner W. H. , Mosca D. H.
Published: September 2015

Local order, electronic structure, and magnetic properties of Co-doped VOx films electrochemically grown onto Si are investigated. The films are studied by means of X-ray absorption spectroscopy (XAS) and magnetic measurements. Freshly made films have V2O5·n(H2O) structure with vanadium valence close to +5. XAS data show that insertion of Co in the films does not affect the close environment around V, when compared to the undoped sample, even varying the concentration of Co by ten times. The site symmetry of Co dopant atoms in the films is consistent with an octahedral coordination where Co is surrounded by six oxygen atoms, as supported by X-ray absorption near-edge structure simulations. Furthermore, there is no evidence of the presence of metallic cobalt (Co0) in the films. The incorporation of small amounts of Co turns ferromagnetic undoped samples into paramagnetic ones. The net magnetic moment per unit volume initially decreases with the incorporation of Co and enhances for higher concentrations. Such behavior is consistent with an O vacancy reduction process driven by the insertion of Co in the films.
Cooling field tuned magnetic phase transition and exchange bias-like effect in Y0.9Pr0.1CrO3
Authors: Deng Dongmei , Zheng Jiashun , Yu Dehong , Wang Baomin , Sun Dehui , Avdeev Maxim , Feng Zhenjie , Jing Chao , Lu Bo , Ren Wei , Cao Shixun , Zhang Jincang
Published: September 2015

Cooling magnetic field dependence of magnetic phase transition has been observed in Y0.9Pr0.1CrO3. GzFx order (spin structure of PrCrO3) is dominant after zero field cooling (ZFC), whereas GxFz order (spin structure of YCrO3) is dominant after cooling under a field higher than 100 Oe. Positive/negative exchange bias-like effect, with large vertical shift and small horizontal shift, has been observed after FC/ZFC process. The vertical shift can be attributed to the frozen ordered Pr3+ and Cr3+ spins in magnetic domains, because of the strong coupling between Pr3+ and Cr3+ sublattices; while the horizontal shift is a result of the pinning of spins at the interfaces. The frozen structure is generated by the field used for the measurement of the initial magnetization curve of M(H) for the ZFC cooled sample, while it is generated by the cooling field for the sample cooled under a cooling field higher than 100 Oe.
Demonstration of phosphor-free polarized white light emission from monolithically integrated semipolar InGaN quantum wells
Authors: Kowsz S. J. , Pynn C. D. , Oh S. H. , Farrell R. M. , Speck J. S. , DenBaars S. P. , Nakamura S.
Published: September 2015

We report a device design that monolithically integrates an electrically injected blue light-emitting diode grown on the (202¯1¯) face of a bulk GaN substrate and yellow emitting optically pumped InGaN quantum wells (QWs) grown on the (202¯1) face. Emission peaks are observed at 440 nm and 560 nm from the electrically injected and optically pumped QWs, respectively. The ratio of blue to yellow light can be optimized to result in polarized white light emission from this phosphor-free device. We demonstrate emission with Commission Internationale de l'Eclairage x- and y-chromaticity coordinates of (0.28, 0.29) and an optical polarization ratio of 0.40.
Polycrystalline VO2 film characterization by quantum capacitance measurement
Authors: Wu Zhe , Knighton Talbot , Tarquini Vinicio , Torres David , Wang Tongyu , Sepúlveda Nelson , Huang Jian
Published: September 2015

Capacitance measurement is performed using a home-built bridge on quasi two-dimensional vanadium dioxide films grown on silicon-dioxide/p-doped silicon substrates. Correlated effects appearing in the quantum capacitance are obtained as a function of temperature at low frequencies. The thermodynamic density of states reveals the opening band gap in the insulating monoclinic phase.
Anomalous refraction of light through slanted-nanoaperture arrays on metal surface
Authors: Kim Myungji , Jung Yun Suk , Xi Yonggang , Kim Hong Koo
Published: September 2015

We report a nanoapertured metal surface that demonstrates anomalous refraction of light for a wide range of incident angles. A nanoslit aperture is designed to serve as a tilted vertical-dipole whose radiation pattern orients to a glancing angle direction to substrate. An array of such slanted nanoslits formed in a metal film redirects an incident beam into the direction of negative refraction angle: the aperture-transmitted wave makes a far-field propagation to the tilt-oriented direction of radiation pattern. The thus-designed nanoaperture array demonstrates the −1st order diffraction (i.e., to the negative refraction-angle direction) with well-suppressed background transmission (the zero-order direct transmission and other higher-order diffractions). Engineering the radiation pattern of nanoaperture offers an approach to overcoming the limits of conventional diffractive/refractive optics and complementing metasurface-based nano-optics.
Electrical spin injection in modulation-doped GaAs from an in situ grown Fe/MgO layer
Authors: Shim Seong Hoon , Kim Hyung-jun , Koo Hyun Cheol , Lee Yun-Hi , Chang Joonyeon
Published: September 2015

We study spin accumulation in n-doped GaAs that were electrically injected from Fe via MgO using three-terminal Hanle measurement. The Fe/MgO/GaAs structures were prepared in a cluster molecular beam epitaxy that did not require the breaking of the vacuum. We found the crystal orientation relationship of epitaxial structures Fe[100]//MgO[110]//GaAs[110] without evident defects at the interface. Control of depletion width and interface resistance by means of modulation doping improves spin injection, leading to enhanced spin voltage (ΔV) of 6.3 mV at 10 K and 0.8 mV even at 400 K. The extracted spin lifetime and spin diffusion length of GaAs are 220 ps and 0.77 μm, respectively, at 200 K. MgO tunnel barrier grown in situ with modulation doping at the interface appears to be promising for spin injection into GaAs.
Meta-lens design with low permittivity dielectric materials through smart transformation optics
Authors: Kim Junhyun , Shin Dongheok , Choi Seungjae , Yoo Do-Sik , Seo Ilsung , Kim Kyoungsik
Published: September 2015

We report here a design method based on smart transformation optics (STO) to control the range of the permittivity values of the materials required to manufacture transformation optics devices. In particular, we show that it is possible to reduce the maximum electric permittivity value required to realize a STO device with certain functionality by means of a simple conceptual elastic stretching process. We illustrate the design procedure with two types of collimator meta-lens designs, which we call warping space collimator meta-lens and half fisheye collimator meta-lens, respectively. We provide design examples of these two types of lenses with the help of COMSOL Multiphysics software. These two design examples are fabricated with commonly available dielectric materials by means of 3D printing technology. For the functional verification of these two collimator lenses, we provide measurement results obtained with transverse electric waves of frequency range 7–13GHz.
Brittle-to-ductile transition of lithiated silicon electrodes: Crazing to stable nanopore growth
Authors: Wang Haoran , Wang Xueju , Xia Shuman , Chew Huck Beng
Published: September 2015

Using first principle calculations, we uncover the underlying mechanisms explaining the brittle-to-ductile transition of LixSi electrodes in lithium ion batteries with increasing Li content. We show that plasticity initiates at x = ∼ 0.5 with the formation of a craze-like network of nanopores separated by Si–Si bonds, while subsequent failure is still brittle-like with the breaking of Si–Si bonds. Transition to ductile behavior occurs at x ⩾ 1 due to the increased density of highly stretchable Li–Li bonds, which delays nanopore formation and stabilizes nanopore growth. Collapse of the nanopores during unloading of the LixSi alloys leads to significant strain recovery.
Communication: Rate coefficients of the H + CH4 → H2 + CH3 reaction from ring polymer molecular dynamics on a highly accurate potential energy surface
Authors: Meng Qingyong , Chen Jun , Zhang Dong H.
Published: September 2015

The ring polymer molecular dynamics (RPMD) calculations are performed to calculate rate constants for the title reaction on the recently constructed potential energy surface based on permutation invariant polynomial (PIP) neural-network (NN) fitting [J. Li et al., J. Chem. Phys. 142, 204302 (2015)]. By inspecting convergence, 16 beads are used in computing free-energy barriers at 300 K ≤ T ≤ 1000 K, while different numbers of beads are used for transmission coefficients. The present RPMD rates are in excellent agreement with quantum rates computed on the same potential energy surface, as well as with the experimental measurements, demonstrating further that the RPMD is capable of producing accurate rates for polyatomic chemical reactions even at rather low temperatures.
Microfluidic point-of-care blood panel based on a novel technique: Reversible electroosmotic flow
Authors: Mohammadi Mahdi , Madadi Hojjat , Casals-Terré Jasmina
Published: September 2015

A wide range of diseases and conditions are monitored or diagnosed from blood plasma, but the ability to analyze a whole blood sample with the requirements for a point-of-care device, such as robustness, user-friendliness, and simple handling, remains unmet. Microfluidics technology offers the possibility not only to work fresh thumb-pricked whole blood but also to maximize the amount of the obtained plasma from the initial sample and therefore the possibility to implement multiple tests in a single cartridge. The microfluidic design presented in this paper is a combination of cross-flow filtration with a reversible electroosmotic flow that prevents clogging at the filter entrance and maximizes the amount of separated plasma. The main advantage of this design is its efficiency, since from a small amount of sample (a single droplet ∼10 μl) almost 10% of this (approx 1 μl) is extracted and collected with high purity (more than 99%) in a reasonable time (5–8 min). To validate the quality and quantity of the separated plasma and to show its potential as a clinical tool, the microfluidic chip has been combined with lateral flow immunochromatography technology to perform a qualitative detection of the thyroid-stimulating hormone and a blood panel for measuring cardiac Troponin and Creatine Kinase MB. The results from the microfluidic system are comparable to previous commercial lateral flow assays that required more sample for implementing fewer tests.
Band alignment of HfO2/multilayer MoS2 interface determined by x-ray photoelectron spectroscopy: Effect of CHF3 treatment
Authors: Liu Xinke , He Jiazhu , Liu Qiang , Tang Dan , Jia Fang , Wen Jiao , Lu Youming , Yu Wenjie , Zhu Deliang , Liu Wenjun , Cao Peijiang , Han Sun , Pan Jisheng , He Zhubing , Ang Kah-Wee
Published: September 2015

The energy band alignment between HfO2/multilayer (ML)-MoS2 was characterized using high-resolution x-ray photoelectron spectroscopy. The HfO2 was deposited using an atomic layer deposition tool, and ML-MoS2 was grown by chemical vapor deposition. A valence band offset (VBO) of 1.98 eV and a conduction band offset (CBO) of 2.72 eV were obtained for the HfO2/ML-MoS2 interface without any treatment. With CHF3 plasma treatment, a VBO and a CBO across the HfO2/ML-MoS2 interface were found to be 2.47 eV and 2.23 eV, respectively. The band alignment difference is believed to be dominated by the down-shift in the core level of Hf 4d and up-shift in the core level of Mo 3d, or the interface dipoles, which caused by the interfacial layer in rich of F.
Combined effect of protein and oxygen on reactive oxygen and nitrogen species in the plasma treatment of tissue
Authors: Gaur Nishtha , Szili Endre J. , Oh Jun-Seok , Hong Sung-Ha , Michelmore Andrew , Graves David B. , Hatta Akimitsu , Short Robert D.
Published: September 2015

The influence of protein and molecular, ground state oxygen (O2) on the plasma generation, and transport of reactive oxygen and nitrogen species (RONS) in tissue are investigated. A tissue target, comprising a 1 mm thick gelatin film (a surrogate for real tissue), is placed on top of a 96-well plate; each well is filled with phosphate buffered saline (PBS, pH 7.4) containing one fluorescent or colorimetric reporter that is specific for one of three RONS (i.e., H2O2, NO2−, or OH•) or a broad spectrum reactive oxygen species reporter (2,7-dichlorodihydrofluorescein). A helium cold atmospheric plasma (CAP) jet contacts the top of the gelatin surface, and the concentrations of RONS generated in PBS are measured on a microplate reader. The data show that H2O2, NO2−, or OH• are generated in PBS underneath the target. Independently, measurements are made of the O2 concentration in the PBS with and without the gelatin target. Adding bovine serum albumin protein to the PBS or gelatin shows that protein either raises or inhibits RONS depending upon the O2 concentration. Our results are discussed in the context of plasma-soft tissue interactions that are important in the development of CAP technology for medicine, biology, and food manufacturing.
Secondary resonance magnetic force microscopy using an external magnetic field for characterization of magnetic thin films
Authors: Liu Dongzi , Mo Kangxin , Ding Xidong , Zhao Liangbing , Lin Guocong , Zhang Yueli , Chen Dihu
Published: September 2015

A bimodal magnetic force microscopy (MFM) that uses an external magnetic field for the detection and imaging of magnetic thin films is developed. By applying the external modulation magnetic field, the vibration of a cantilever probe is excited by its magnetic tip at its higher eigenmode. Using magnetic nanoparticle samples, the capacity of the technique which allows single-pass imaging of topography and magnetic forces is demonstrated. For the detection of magnetic properties of thin film materials, its signal-to-noise ratio and sensitivity are demonstrated to be superior to conventional MFM in lift mode. The secondary resonance MFM technique provides a promising tool for the characterization of nanoscale magnetic properties of various materials, especially of magnetic thin films with weak magnetism.
Design and optimization of Ag-dielectric core-shell nanostructures for silicon solar cells
Authors: Chen Feng-Xiang , Wang Xi-Cheng , Xia Dong-Lin , Wang Li-Sheng
Published: September 2015

Metal-dielectric core-shell nanostructures have been proposed as a light trapping scheme for enhancing the optical absorption of silicon solar cells. As a potential application of such enhanced effects, the scattering efficiencies of three core-shell structures (Ag@SiO2, Ag@TiO2, and Ag@ZrO2) are discussed using the Mie Scattering theory. For compatibility with experiment results, the core diameter and shell thickness are limited to 100 and 30 nm, respectively, and a weighted scattering efficiency is introduced to evaluate the scattering abilities of different nanoparticles under the solar spectrum AM 1.5. The simulated results indicate that the shell material and thickness are two key parameters affecting the weighted scattering efficiency. The SiO2 is found to be an unsuitable shell medium because of its low refractive index. However, using the high refractive index mediumTiO2 in Ag@TiO2 nanoparticles, only the thicker shell (30 nm) is more beneficial for light scattering. The ZrO2 is an intermediate refractive index material, so Ag@ZrO2 nanoparticles are the most effective core-shell nanostructures in these silicon solar cells applications.
Water-processed carbon nanotube/graphene hybrids with enhanced field emission properties
Authors: Song Meng , Xu Peng , Song Yenan , Wang Xu , Li Zhenhua , Shang Xuefu , Wu Huizhen , Zhao Pei , Wang Miao
Published: September 2015

Integrating carbon nanotubes (CNTs) and graphene into hybrid structures provides a novel approach to three dimensional (3D) materials with advantageous properties. Here we present a water-processing method to create integrated CNT/graphene hybrids and test their field emission properties. With an optimized mass ratio of CNTs to graphene, the hybrid shows a significantly enhanced field emission performance, such as turn-on electric field of 0.79 V/μm, threshold electric field of 1.05 V/μm, maximum current density of 0.1 mA/cm2, and field enhancement factor of ∼1.3 × 104. The optimized mass ratio for field emission emphasizes the importance of both CNTs and graphene in the hybrid. We also hypothesize a possible mechanism for this enhanced field emission performance from the CNT/graphene hybrid. During the solution treatment, graphene oxide behaves as surfactant sheets for CNTs to form a well dispersed solution, which leads to a better organized 3D structure with more conducting channels for electron transport.
A method to determine the number of nanoparticles in a cluster using conventional optical microscopes
Authors: Kang Hyeonggon , Attota Ravikiran , Tondare Vipin , Vladár András E. , Kavuri Premsagar
Published: September 2015

We present a method that uses conventional optical microscopes to determine the number of nanoparticles in a cluster, which is typically not possible using traditional image-based optical methods due to the diffraction limit. The method, called through-focus scanning optical microscopy (TSOM), uses a series of optical images taken at varying focus levels to achieve this. The optical images cannot directly resolve the individual nanoparticles, but contain information related to the number of particles. The TSOM method makes use of this information to determine the number of nanoparticles in a cluster. Initial good agreement between the simulations and the measurements is also presented. The TSOM method can be applied to fluorescent and non-fluorescent as well as metallic and non-metallic nano-scale materials, including soft materials, making it attractive for tag-less, high-speed, optical analysis of nanoparticles down to 45 nm diameter.
Made-in-Canada Humour
Authors: Rasporich Beverly J.
Published: September 2015

Made-in-Canada-Humour is an interdisciplinary survey and analysis of Canadian humour and humorists in the nineteenth and twentieth centuries. The book focuses on a variety of genres. It includes celebrated Canadian writers and poets with ironic and satiric perspectives; oral storytellers of tall tales in the country and the city; newspaper print humorists; representative national and regional cartoonists; and comedians of stage, radio and television. The humour gives voice to Canadian values and experiences, and consequently, techniques and styles of humour particular to the country. While a persistent comic theme has been joking at the expense of the United States, both countries have influenced one another’s humour. Canada’s unique humorous tradition also reflects its emergence from a colonial country to a postcolonial and postmodern nation with contemporary humour that addresses gender and racial issues.
Discovery of an intermolecular disulfide bond required for the thermostability of a heterodimeric protein from the thermophile Hydrogenobacter thermophilus
Authors: Kim Keug Tae , Chiba Yoko , Arai Hiroyuki , Ishii Masaharu
Published: September 2015

Factors that increase protein thermostability are of considerable interest in both scientific and industrial fields. Disulfide bonds are one of such factors that increase thermostability, but are rarely found in intracellular proteins because of the reducing environment of the cytosol. Here, we report the first example of an intermolecular disulfide bond between heteromeric subunits of a novel-type phosphoserine phosphatase from a thermophilic bacterium Hydrogenobacter thermophilus, which contributes to the protein thermostability at the physiological temperature. Comparison of remaining soluble proteins between wild-type and cysteine-deleted mutant using SDS-PAGE revealed that the disulfide bond increases the thermostability of the whole protein by tightly connecting a subunit with low solubility to the partner with higher solubility. Furthermore, it was strongly suggested that the disulfide bond is formed and contributes to the stability in vivo. This finding will open new avenues for the design of proteins with increased thermostability.
Vocal fundamental and formant frequencies affect perceptions of speaker cooperativeness
Authors: Knowles Kristen K. , Little Anthony C.
Published: September 2015

In recent years, the perception of social traits in faces and voices has received much attention. Facial and vocal masculinity are linked to perceptions of trustworthiness; however, while feminine faces are generally considered to be trustworthy, vocal trustworthiness is associated with masculinized vocal features. Vocal traits such as pitch and formants have previously been associated with perceived social traits such as trustworthiness and dominance, but the link between these measurements and perceptions of cooperativeness have yet to be examined. In Experiment 1, cooperativeness ratings of male and female voices were examined against four vocal measurements: fundamental frequency ( F0), pitch variation ( F0−SD), formant dispersion ( Df), and formant position ( Pf). Feminine pitch traits ( F0 and F0−SD) and masculine formant traits ( Df and Pf) were associated with higher cooperativeness ratings. In Experiment 2, manipulated voices with feminized F0 were found to be more cooperative than voices with masculinized F0, among both male and female speakers, confirming our results from Experiment 1. Feminine pitch qualities may indicate an individual who is friendly and non-threatening, while masculine formant qualities may reflect an individual that is socially dominant or prestigious, and the perception of these associated traits may influence the perceived cooperativeness of the speakers.
Political reform attempts in Saudi Arabia
Authors: Al-Zaidi Mufeed
Published: September 2015

There have been reform movements and various attempts at reform in Saudi Arabia since the early 1990s. This study attempts to put forward and discuss the hypothesis that may be summarized as the impact of political reform measures on the kingdom in achieving harmony between the state and society to guarantee stability and security in the present and for future generations. The study analyzes proposals for political reform in the country and the scope of the government’s response to these during the past years. This is especially relevant in view of the Arab movement for change in the Gulf region and the Arab world in general, and the repercussions of global terrorism in Syria and Iraq and its intensification that is threatening the borders of the Gulf Cooperation Council (GCC) countries, including Saudi Arabia.
How Valuable Are Chances?
Authors: Stefánsson H. Orri , Bradley Richard
Published: September 2015

Chance Neutrality is the thesis that, conditional on some proposition being true (or being false), its chance of being true should be a matter of practical indifference. The aim of this article is to examine whether Chance Neutrality is a requirement of rationality. We prove that given Chance Neutrality, the Principal Principle entails a thesis called Linearity; the centerpiece of von Neumann and Morgenstern’s expected utility theory. With this in mind, we argue that the Principal Principle is a requirement of practical rationality but that Linearity is not and, hence, that Chance Neutrality is not rationally required.
On the quenching behavior of the MEMS with fringing field
Authors: Luo Xue , Yau Stephen
Published: September 2015

The singular parabolic problem

u
t

−
△
u
=
λ

1
+
δ

|

∇
u

|

2

(
1
−
u

)
2

u_t-\triangle u=\lambda {\frac {1+\delta |\nabla u|^2}{(1-u)^2}}

on a bounded domain

Ω
\Omega

of

R

n

\mathbb {R}^n

with Dirichlet boundary condition models the microelectromechanical systems (MEMS) device with fringing field. In this paper, we focus on the quenching behavior of the solution to this equation. We first show that there exists a critical value

λ
δ
∗

>
0

\lambda _\delta ^*>0

such that if

0
>
λ
>

λ
δ
∗

0>\lambda >\lambda _\delta ^*

, all solutions exist globally, while for

λ
>

λ
δ
∗

\lambda >\lambda _\delta ^*

, all the solutions will quench in finite time. The estimate of the quenching time in terms of large voltage

λ
\lambda

is investigated. Furthermore, the quenching set is a compact subset of

Ω
\Omega

, provided

Ω
\Omega

is a convex bounded domain in

R

n

\mathbb {R}^n

. In particular, if the domain

Ω
\Omega

is radially symmetric, then the origin is the only quenching point. We not only derive the one-side estimate of the quenching rate, but also further study the refined asymptotic behavior of the finite quenching solution.
On the Cucker-Smale flocking with alternating leaders
Authors: Li Zhuchun , Ha Seung-Yeal
Published: September 2015

We discuss the emergent flocking behavior in a group of Cucker-Smale flocking agents under rooted leadership with alternating leaders. It is well known that the network topology regulates the emergent behaviors of flocks. All existing results on the Cucker-Smale model with leader-follower topologies assume a fixed leader during the temporal evolution process. The rooted leadership is the most general topology taking a leadership. Motivated by collective behaviors observed in the flocks of birds, swarming fishes and potential engineering applications, we consider the rooted leadership with alternating leaders; that is, at each time slice there is a leader, but it can be switched among the agents from time to time. We provide several sufficient conditions leading to the asymptotic flocking among the Cucker-Smale agents under rooted leadership with alternating leaders.
Cas-Designer: a web-based tool for choice of CRISPR-Cas9 target sites
Authors: Park Jeongbin , Bae Sangsu , Kim Jin-Soo
Published: September 2015

Summary: We present Cas-Designer, a user-friendly program to aid researchers in choosing appropriate target sites in a gene of interest for type II CRISPR/Cas-derived RNA-guided endonucleases, which are now widely used for biomedical research and biotechnology. Cas-Designer rapidly provides the list of all possible guide RNA sequences in a given input DNA sequence and their potential off-target sites including bulge-type sites in a genome of choice. In addition, the program assigns an out-of-frame score to each target site to help users choose appropriate sites for gene knockout. Cas-Designer shows the results in an interactive table and provides user-friendly filter functions.

Availability and implementation: Free access at http://rgenome.net/cas-designer/.

Contact:  sangsubae@hanyang.ac.kr or jskim01@snu.ac.kr

Supplementary information:  Supplementary data are available at Bioinformatics online.
Pushing Idealism Beyond its Limits
Authors: Arnold Dan
Published: September 2015

Arguing that progress toward enlightenment requires gradually developing specific cognitive achievements, the Buddhist philosopher Kamalaśīla alternately appeals to scripture and reasoning in ways that typify the always hermeneutical context for the development of Indian Buddhist philosophy. This context did not preclude great originality; his distinctive appeal to both of the Mahāyāna tradition’s main streams of thought (Yogācāra and Madhyamaka) creatively appropriates a famous Yogācāra argument for idealism—an argument against the coherence of any account of atoms—in service of a conclusion that finally undermines the idealism the argument originally supported. The best argument for Madhyamaka, Kamalaśīla thus urges, consists in pressing an argument for idealism against itself. In developing this line of argument, Kamalaśīla well exemplifies the scholastic character of his tradition.
Reflexive Awareness and No-Self
Authors: Chadha Monima
Published: September 2015

This chapter discusses the Yogācāra doctrine of reflexive self-awareness (svasaṃvedana) as introduced by Dignāga and defended by Dharmakīrti against Hindu opponents as well as later Buddhist Mādhyamikas. It explains the doctrine of reflexive awareness and the arguments offered by Dignāga and Dharmakīrti. It appears that the doctrine of reflexive awareness is in conflict with other central commitments of Buddhist philosophers: the no-self theory and the theory of momentariness. The distinctive contribution of this chapter is to explicate a constitutive role for reflexive awareness in the account of conscious experience and point toward a resolution of the apparent conflict.
Markets/Marketization
Authors: Marchand Marianne H. , del Carmen Osorno Velázquez Rocio
Published: September 2015

Feminists from a range of disciplines and perspectives theorized the basic androcentric bias in neoliberal (or neoclassical) economic theory. This chapter analyzes the market as a gendered spatial and conceptual construction and shows how marketization—the encroachment of the market upon noneconomic spheres—involves gendered practices that are embedded in and constitutive of, and transformative of unequal power relations of gender, race, ethnicity, class, sexuality, age, national origin, and geopolitical locations. It traces how neoliberal global restructuring has affected women’s participation in productive, reproductive, and virtual economies, including agribusiness, industrial production, the service sector, transnational care work, and sex work, and in the area of affective labor. And it demonstrates how the financialization of noneconomic spheres of the global economy insert women from the global North and the global South into the global financial sector through microfinancing schemes, which subject them to the disciplinary and regulatory power of global finance.
Food as a Means for Female Power Struggles
Authors: De Backer Charlotte , Hudders Liselot , Fisher Maryanne L.
Published: September 2015

Food often brings to mind diet and health, but it also has important social functions. Food is about so much more than just caloric intake and providing nourishment to oneself and others under one’s care. It signals, for example, care about oneself and others by means of careful planning, preparation, and consumption. After reviewing several perspectives on the social dynamics of food, this chapter connects food to women’s intrasexual competition. Specifically, it addresses how cooking and food intake are self-promotion strategies, not only due to one’s demonstration of an excellent domestic ability to a potential audience but also by boosting one’s physical attractiveness via controlling food intake. While there exists little direct, empirical evidence on the relationship between interpersonal competition and food preparation and consumption, research from a wide array of topics offers support. The chapter closes with numerous directions for future research in the area of food studies.
Evolution of Artistic and Aesthetic Propensities through Female Competitive Ornamentation
Authors: Varella Marco A. C. , Varella Valentova Jaroslava , Fernández Ana María
Published: September 2015

This chapter highlights and discusses the role of women’s competitive ornamentation as one of the relevant, and so far overlooked, ancestral selective pressures in the evolution of artistic propensities. The authors critically discuss how and why sex differences and sexual selection processes acting on women have been disregarded for more than a decade. The authors review available convergent evidence about sex differences in aesthetics and artistic propensities showing that, overall, women outnumber men. Then the authors propose and show evidence that higher women’s inclination toward artistic domains, including ornamentation of body, behavior, and objects/places, can serve as a social arena for attracting/maintaining mates and dealing with rivals, primarily through self-promotion via competitive ornamentation. The chapter concludes by developing connections with related theories that broaden the scope of the field and highlight predictions for future research.
Female Heights and Economic Development
Authors: Oxley Deborah
Published: September 2015

Female heights matter. They matter for girls’ and women’s health and productivity, as a measure of inequality, and—significantly—as a bridge transferring welfare across generations. This chapter examines some of the early historiography on female stature and summarizes the historical evidence. The focus then shifts to how we understand the growth of girls versus boys and the methods used to measure historical populations. The chapter then outlines some of the risks of being stunted, identified in a set of empirical relationships among height, weight, morbidity, and mortality that are a function of both age and sex. The chapter then looks at the unique role of mothers and the way their stature not only records the accumulated experience of their own nutrition and welfare history, but how it intimately shapes the generations to come, critically influencing future economic performance.
Height and Wages
Authors: Hübler Olaf
Published: September 2015

This chapter discusses the relationship between height and wages under a theoretical and empirical perspective. Many channels explain why height and wage are positively correlated. A major strand is based on unobserved cognitive and physical abilities that are connected with height and that influence wages. Further indirect links are possible via schooling, health, and risk aversion. Finally, discrimination and satisfaction are possible potential causes that a statistical association is well-founded. Most empirical investigations only analyze a direct linear relationship and find a positive height premium roughly between less than 1% and 10% due to an increase of 10 cm in height. The applied methods can partially explain the differences. Measurement errors, unobserved heterogeneity, endogeneity, and nonlinearities are methodological problems that should be considered. Moreover, the height premium varies with the specification. The incorporation of nutrition, health, education, leadership, physical capacity, age, weight, and, especially, gender influence estimation results.
Global BMI Trends
Authors: Kromeyer-Hauschild Katrin , Moss Anja , Wabitsch Martin
Published: September 2015

This chapter reviews the current prevalence of overweight and obesity and trends over time in body mass index (BMI) and in the distribution of BMI worldwide. During the past three decades, a consistent increase in the prevalence of overweight and obesity in children and adults has been documented worldwide, with substantial differences between countries and regions. Evidence shows that the BMI increase began among those born early in the 20th century, with considerable variation over time. Simultaneously, the distribution of BMI has shifted in a skewed fashion, with marked changes in the upper BMI range indicating that the heaviest people have become even heavier whereas lean people have shown only small changes. Rates of the prevalence of underweight children are falling in developing countries with parallel increases in the rates of overweight children as a result of globalization. Underweight, overweight, and obesity still represent a significant health issue.
Racial Differences in Health in the United States
Authors: Boustan Leah , Margo Robert A.
Published: September 2015

The United States has a long and ongoing history of racial inequality. This chapter surveys the literature on one aspect of that history: long-run trends in racial differences in health. We focus on standard measures such as infant mortality and life expectancy but also consider available data on specific diseases and chronic conditions. Our basic conclusion is that large improvements have occurred in the average health of African Americans during the 20th century, both in absolute terms and relative to whites. These health advancements occurred steadily throughout the 20th century, with the peak period of improvement between 1920 and 1945 (infant mortality) and 1940 and 1960 (overall life expectancy). We attribute the improvements to successful efforts to fight specific diseases, improvements in public health, and narrowing of racial gaps in education and income. Although racial inequality in health outcomes has fallen in the long term, significant disparities remain today.