bluuebunny/crossref_metadata_2025 huggingface dataset:
Higher-order cyclization reactions of alkenyl Fischer carbene complexes: a new selective all-carbon [8 + 2] cyclization with 8-methoxyheptafulvene and computational mechanistic analysis
Authors: García-Rodríguez Jaime , González Jairo , Santamaría Javier , Suárez-Sobrino Ángel L. , Rodríguez Miguel A.
Published: June 2016

A new all-carbon [8 +2] cycloaddition of alkenyl Fischer carbene complexes is described.
Small-molecule activation at Au(iii): metallacycle construction from ethylene, water, and acetonitrile
Authors: Holmsen Marte Sofie Martinsen , Nova Ainara , Balcells David , Langseth Eirin , Øien-Ødegaard Sigurd , Tråseth Eline Aasen , Heyn Richard H. , Tilset Mats
Published: June 2016

Incorporation of the simple, readily available, building blocks ethylene, water and acetonitrile into Au(tpy)(OCOCF3)2 (tpy = 2-(p-tolyl)pyridine) in a one-step reaction leads to high yields of a new 6-membered ring gold(iii) metallacycle complex.
Small, beautiful and magnetically exotic: {V4W2}- and {V4W4}-type polyoxometalates
Authors: Rasmussen Maren , Näther Christian , van Leusen Jan , Warzok Ulrike , Schalley Christoph A. , Kögerler Paul , Bensch Wolfgang
Published: June 2016

Vanadyl diene cations arrange around two- and four-nuclear polytungstate groups, effectively blocking further condensation and resulting in exceptionally small heterometal polyoxometalates.
Water oxidation catalysis – role of redox and structural dynamics in biological photosynthesis and inorganic manganese oxides
Authors: Zaharieva I. , González-Flores D. , Asfari B. , Pasquini C. , Mohammadi M. R. , Klingan K. , Zizak I. , Loos S. , Chernev P. , Dau H.
Published: June 2016

Water oxidation is pivotal in biological photosynthesis, where it is catalyzed by a protein-bound metal complex with a Mn4Ca-oxide core; related synthetic catalysts may become key components in non-fossil fuel technologies.
Hardwiring microbes via direct interspecies electron transfer: mechanisms and applications
Authors: Cheng Qiwen , Call Douglas F.
Published: June 2016

Direct interspecies electron transfer (DIET) has important implications for the design and operation of biological treatment processes.
The antiviral effects of acteoside and the underlying IFN-γ-inducing action
Authors: Song Xun , He Jiang , Xu Hong , Hu Xiao-Peng , Wu Xu-Li , Wu Hai-Qiang , Liu Li-Zhong , Liao Cheng-Hui , Zeng Yong , Li Yan , Hao Yue , Xu Chen-Shu , Fan Long , Zhang Jian , Zhang Hong-Jie , He Zhen-Dan
Published: June 2016

Acteoside, a natural phenylpropanoid glycoside from Kuding Tea, enhanced IFN-γ production in mouse lymphocytes in a dose-dependent manner, particularly in the CD4+ and CD8+ subsets of T lymphocytes.
Formic acid-mediated liquefaction of chitin
Authors: Zhang Jiaguang , Yan Ning
Published: June 2016

We report pure formic acid-mediated liquefaction of chitin for the first time.
Shrinking, growing, and bursting: microfluidic equilibrium control of water-in-water droplets
Authors: Moon Byeong-Ui , Hwang Dae Kun , Tsai Scott S. H.
Published: June 2016

We demonstrate a new microfluidic technique that controls the shrinking, growing, and bursting of aqueous two phase system (ATPS) droplets.
“DNA–Teflon” sequence-controlled polymers
Authors: de Rochambeau Donatien , Barłóg Maciej , Edwardson Thomas G. W. , Fakhoury Johans J. , Stein Robin S. , Bazzi Hassan S. , Sleiman Hanadi F.
Published: June 2016

Efficient automated synthesis of sequence-controlled “DNA–Teflon” polymers with potential drug delivery and bioimaging applications.
Fabrication of amphiphilic fluorescent nanoparticles with an AIE feature via a one-pot clickable mercaptoacetic acid locking imine reaction: synthesis, self-assembly and bioimaging
Authors: Wan Qing , Liu Meiying , Xu Dazhuang , Mao Liucheng , Huang Hongye , Gao Peng , Deng Fengjie , Zhang Xiaoyong , Wei Yen
Published: June 2016

Water dispersible and non-toxic AIE active fluorescent organic nanoparticles were fabricatedviaa one-pot clickable mercaptoacetic acid locking imine reaction.
The facile preparation of novel magnetic zirconia composites with the aid of carboxymethyl chitosan and their efficient removal of dye
Authors: Wu Taiheng , Shao Qian , Ge Shengsong , Bao Liwei , Liu Qingyun
Published: June 2016

The Fe3O4/ZrO2–CMCS composites exhibited high adsorption activity for sunset yellow. After eliminating the CMCS in the Fe3O4/ZrO2–CMCS, the as-obtained Fe3O4/ZrO2 showed enhanced photocatalytic activity in degrading Rh B under sunlight irradiation.
Three-dimensional potassium niobate nanoarray on vermiculite for high-performance photocatalyst fabricated by an in situ hydrothermal process
Authors: Wang Yuwei , Kong Xianggui , Tian Weiliang , Lei Deqiang , Lei Xiaodong
Published: June 2016

The 3D KNbO3/VMT hierarchical architecture can be synthesized by a facile hydrothermal method, and shows high visible light photocatalytic activity.
Oxygen vacancy-related room temperature ferromagnetism in TiO2 nanohole arrays
Authors: Liu Yanping , Feng Shangshen , Li Zhigang , Zhang Li , Wang Guping , Chen Weiping , Wang Tianle , Zhong Wenwu
Published: June 2016

Room temperature ferromagnetism was observed in hole-like TiO2 nanostructure arrays prepared by a monolayer colloidal crystal template.
Development of a novel H2S and GSH detection cocktail for fluorescence imaging
Authors: Cheng Juan , Liu Meng , Shao Baihao , Zhang Shuai , Li Jia , Hu Yongzhou , Li Xin , Zang Yi
Published: June 2016

A highly sensitive fluorescent detection cocktail has been developed for the simultaneous imaging of H2S and GSH in live cells.
Fabrication and high radiation-resistant properties of functionalized carbon nanotube reinforced novolac epoxy resin nanocomposite coatings
Authors: Chang Shuquan , Li Jin , Han Wei , Zhang Zheng , Chang Ling , Chen Wei , Li Zheng , Dai Yaodong , Chen Da
Published: June 2016

Functionalized MWCNT/novolac epoxy nanocomposite coatings with high radiation resistance were successfully fabricated and studied.
Reversible encapsulation of silver nanoparticles into the helix of amylose (water soluble starch)
Authors: Zaheer Zoya , Aazam Elham Shafik , Hussain Shokit
Published: June 2016

Natural biodegradable polymeric starch capped Ag-nanoparticles (AgNPs) were prepared by using extract of Dioscorea deltoidea in the presence of starch.
Polarized Raman spectra of phosphorene in edge and top view measuring configurations
Authors: Baibarac M. , Nila A. , Baltog I.
Published: June 2016

We demonstrate the anisotropic features of the A1g, B2gand A2gvibrational Raman modes of phosphorene by performing for the first time a comparison of two orthogonal polarized Raman scattering studies in edge and top view measuring configurations.
Microwave-assisted methylation of dihydroxybenzene derivatives with dimethyl carbonate
Authors: Lui Matthew Y. , Lokare Kapil S. , Hemming Ellen , Stanley Jessica N. G. , Perosa Alvise , Selva Maurizio , Masters Anthony F. , Maschmeyer Thomas
Published: June 2016

Dihydroxybenzene derivatives were methylated with dimethyl carbonate to generate useful synthetic intermediates for wide range of applications.
Photocatalytic H2 evolution for α-, β-, γ-Ga2O3 and suppression of hydrolysis of γ-Ga2O3 by adjusting pH, adding a sacrificial agent or loading a cocatalyst
Authors: Li Liangju , Ma Biao , Xie Huan , Yue Mufei , Cong Rihong , Gao Wenliang , Yang Tao
Published: June 2016

γ-Ga2O3 exhibited the highest photocatalytic activity among studied photocatalysts, however, it suffered from slight hydrolysis, which can be efficiently suppressed by several methods.
Structural evolution induced preferential occupancy of designated cation sites by Eu2+ in M5(Si3O9)2 (M = Sr, Ba, Y, Mn) phosphors
Authors: Wei Yi. , Lin Chun Che , Quan Zewei , Molokeev Maxim S. , Atuchin Victor V. , Chan Ting-Shan , Liang Yujun , Lin Jun , Li Guogang
Published: June 2016

A schematic presentation for the unexpected blue-shifted luminescence of Eu2+ in M5(Si3O9)2 (M = Sr, Ba, Y, Eu, Mn) based on the preferential occupancy at the designated cation sites.
Synthesis of diatrizoic acid-modified LAPONITE® nanodisks for CT imaging applications
Authors: Mustafa Rania , Hu Yong , Yang Jia , Chen Jingwen , Wang Han , Zhang Guixiang , Shi Xiangyang
Published: June 2016

Nanoscale diatrizoic acid-modified LAPONITE® nanodisks can be synthesized for CT imaging of animal organs and tumors in vivo.
Hybrid nanostructures of TiO2 nanorod array/Cu2O with a CH3NH3PbI3 interlayer for enhanced photocatalytic activity and photoelectrochemical performance
Authors: Fu Ke , Huang Jinzhao , Yao Nannan , Deng Xiaolong , Xu Xijin , Li Lin
Published: June 2016

A novel composite photocatalyst constructed from TiO2 NRAs, CH3NH3PbI3 and Cu2O exhibits highly efficient visible light photocatalysis activity.
Palladium-catalyzed carbonylative coupling of aryl iodides with an organocopper reagent: a straightforward procedure for the synthesis of aryl trifluoromethyl ketones
Authors: Zhu Fengxiang , Yang Guangfu , Zhou Shaolin , Wu Xiao-Feng
Published: June 2016

A palladium-catalyzed carbonylative coupling of aryl iodides with a (trifluoromethyl)copper reagent has been developed.
Tin nanoparticles decorated copper oxide nanowires for selective electrochemical reduction of aqueous CO2to CO
Authors: Zhao Yong , Wang Caiyun , Wallace Gordon G.
Published: June 2016

A low-cost tin-nanoparticles-decorated copper oxide nanowire electrocatalyst is developed to selectively converse aqueous CO2to CO at modest overpotentials. This Cu–Sn hybrid catalyst exhibits excellent selectivity, activity and durability.
Functional magnetic Prussian blue nanoparticles for enhanced gene transfection and photothermal ablation of tumor cells
Authors: Xue Peng , Bao Jingnan , Zhang Lei , Xu Zhigang , Xu Chenjie , Zhang Yilei , Kang Yuejun
Published: June 2016

Functional magnetic Prussian blue nanoparticles as a gene carrier and photothermal agent for multi-modal cancer treatment under magnetic targeting.
Enhanced conformational sampling to visualize a free-energy landscape of protein complex formation
Authors: Iida Shinji , Nakamura Haruki , Higo Junichi
Published: June 2016

We introduce various, recently developed, generalized ensemble methods, which are useful to sample various molecular configurations emerging in the process of protein–protein or protein–ligand binding. The methods introduced here are those that have been or will be applied to biomolecular binding, where the biomolecules are treated as flexible molecules expressed by an all-atom model in an explicit solvent. Sampling produces an ensemble of conformations (snapshots) that are thermodynamically probable at room temperature. Then, projection of those conformations to an abstract low-dimensional space generates a free-energy landscape. As an example, we show a landscape of homo-dimer formation of an endothelin-1-like molecule computed using a generalized ensemble method. The lowest free-energy cluster at room temperature coincided precisely with the experimentally determined complex structure. Two minor clusters were also found in the landscape, which were largely different from the native complex form. Although those clusters were isolated at room temperature, with rising temperature a pathway emerged linking the lowest and second-lowest free-energy clusters, and a further temperature increment connected all the clusters. This exemplifies that the generalized ensemble method is a powerful tool for computing the free-energy landscape, by which one can discuss the thermodynamic stability of clusters and the temperature dependence of the cluster networks.
Coupled microstrip line Wilkinson power divider with open‐stubs for compensation
Authors: Wang X. , Ohira M. , Ma Z.
Published: June 2016

Coupled microstrip line section is a well‐known technology for various circuits miniaturisation. Because the phase velocity difference of coupled microstrip line section exists in practical circuit, compensation method is needed to maintain circuit performance. In this Letter, extra open‐stubs are newly inserted between coupled microstrip line section and two output ports for compensation. Compared with previous work, by using open‐stubs, a novel and flexible compensation method is newly presented, where, both Γev and Γod are adjusted for compensation at the same time, the proposed circuit not only provides simple structure and easy fabrication but also compensates arbitrary coupling strength without soldering parasitic effect in high frequency operation. Through even‐ and odd‐mode analysis, design equations are derived and discussed in Smith chart. In experiment, one circuit was fabricated, the measurement results showed good agreement with theoretical results.
A gas-dynamical approach to radiation pressure acceleration
Authors: Schmidt Peter , Boine-Frankenheim Oliver
Published: June 2016

The study of high intensity ion beams driven by high power pulsed lasers is an active field of research. Of particular interest is the radiation pressure acceleration, for which simulations predict narrow band ion energies up to GeV. We derive a laser-piston model by applying techniques for non-relativistic gas-dynamics. The model reveals a laser intensity limit, below which sufficient laser-piston acceleration is impossible. The relation between target thickness and piston velocity as a function of the laser pulse length yields an approximation for the permissible target thickness. We performed one-dimensional Particle-In-Cell simulations to confirm the predictions of the analytical model. These simulations also reveal the importance of electromagnetic energy transport. We find that this energy transport limits the achievable compression and rarefies the plasma.
Arbitrary amplitude fast electron-acoustic solitons in three-electron component space plasmas
Authors: Mbuli L. N. , Maharaj S. K. , Bharuthram R. , Singh S. V. , Lakhina G. S.
Published: June 2016

We examine the characteristics of fast electron-acoustic solitons in a four-component unmagnetised plasma model consisting of cool, warm, and hot electrons, and cool ions. We retain the inertia and pressure for all the plasma species by assuming adiabatic fluid behaviour for all the species. By using the Sagdeev pseudo-potential technique, the allowable Mach number ranges for fast electron-acoustic solitary waves are explored and discussed. It is found that the cool and warm electron number densities determine the polarity switch of the fast electron-acoustic solitons which are limited by either the occurrence of fast electron-acoustic double layers or warm and hot electron number density becoming unreal. For the first time in the study of solitons, we report on the coexistence of fast electron-acoustic solitons, in addition to the regular fast electron-acoustic solitons and double layers in our multi-species plasma model. Our results are applied to the generation of broadband electrostatic noise in the dayside auroral region.
Stimulated Raman spectroscopy and nanoscopy of molecules using near field photon induced forces without resonant electronic enhancement gain
Authors: Tamma Venkata Ananth , Huang Fei , Nowak Derek , Kumar Wickramasinghe H.
Published: June 2016

We report on stimulated Raman spectroscopy and nanoscopy of molecules, excited without resonant electronic enhancement gain, and recorded using near field photon induced forces. Photon-induced interaction forces between the sharp metal coated silicon tip of an Atomic Force Microscope (AFM) and a sample resulting from stimulated Raman excitation were detected. We controlled the tip to sample spacing using the higher order flexural eigenmodes of the AFM cantilever, enabling the tip to come very close to the sample. As a result, the detection sensitivity was increased compared with previous work on Raman force microscopy. Raman vibrational spectra of azobenzene thiol and l-phenylalanine were measured and found to agree well with published results. Near-field force detection eliminates the need for far-field optical spectrometer detection. Recorded images show spatial resolution far below the optical diffraction limit. Further optimization and use of ultrafast pulsed lasers could push the detection sensitivity towards the single molecule limit.
Modeling and experiment of the suspended seismometer concept for attenuating the contribution of tilt motion in horizontal measurements
Authors: Matichard F. , Evans M. , Mittleman R. , MacInnis M. , Biscans S. , Dooley K. L. , Sohier H. , Lauriero A. , Paris H. , Koch J. , Knothe P. , Carbajo A. , Dufort C.
Published: June 2016

Tilt-horizontal coupling in inertial sensors limits the performance of active isolation systems such as those used in gravitational wave detectors. Inertial rotation sensors can be used to subtract the tilt component from the signal produced by horizontal inertial sensors, but such techniques are often limited by the sensor noise of the tilt measurement. A different approach is to mechanically filter the tilt transmitted to the horizontal inertial sensor, as discussed in this article. This technique does not require an auxiliary rotation sensor and can produce a lower noise measurement. The concept investigated uses a mechanical suspension to isolate the inertial sensor from input tilt. Modeling and simulations show that such a configuration can be used to adequately attenuate the tilt transmitted to the instrument, while maintaining translation sensitivity in the frequency band of interest. The analysis is supported by experimental results showing that this approach is a viable solution to overcome the tilt problem in the field of active inertial isolation.
Fluorinated graphene films with graphene quantum dots for electronic applications
Authors: Antonova I. V. , Nebogatikova N. A. , Prinz V. Ya.
Published: June 2016

This work analyzes carrier transport, the relaxation of non-equilibrium charge, and the electronic structure of fluorinated graphene (FG) films with graphene quantum dots (GQDs). The FG films with GQDs were fabricated by means of chemical functionalization in an aqueous solution of hydrofluoric acid. High fluctuations of potential relief inside the FG barriers have been detected in the range of up to 200 mV. A phenomenological expression that describes the dependence of the time of non-equilibrium charge emission from GQDs on quantum confinement levels and film thickness (potential barrier parameters between GQDs) is suggested. An increase in the degree of functionalization leads to a decrease in GQD size, the removal of the GQD effect on carrier transport, and the relaxation of non-equilibrium charge. The study of the electronic properties of FG films with GQDs has revealed a unipolar resistive switching effect in the films with a relatively high degree of fluorination and a high current modulation (up to ON/OFF ∼ 104–105) in transistor-like structures with a lower degree of fluorination. 2D films with GQDs are believed to have considerable potential for various electronic applications (nonvolatile memory, 2D connections with optical control and logic elements).
Variable coefficient Davey-Stewartson system with a Kac-Moody-Virasoro symmetry algebra
Authors: Güngör F. , Özemir C.
Published: June 2016

We study the symmetry group properties of the variable coefficient Davey-Stewartson (vcDS) system. The Lie point symmetry algebra with a Kac-Moody-Virasoro (KMV) structure is shown to be isomorphic to that of the usual (constant coefficient) DS system if and only if the coefficients satisfy some conditions. These conditions turn out to coincide with those for the vcDS system to be transformable to the DS system by a point transformation. The equivalence group of the vcDS system is applied to pick out the integrable subsystems from a class of non-integrable ones. Additionally, the full symmetry group of the DS system is derived explicitly without exponentiating its symmetry algebra. Lump solutions (rationally localized in all directions in ℝ2) introduced by Ozawa for the DS system are shown to hold even for the vcDS system precisely when the system belongs to the integrable class, i.e., equivalent to the DS system. These solutions can be used for establishing exact blow-up solutions in finite time in the space L2(ℝ2) in the focusing case.
Dependence of Brillouin frequency shift on water absorption ratio in polymer optical fibers
Authors: Minakawa Kazunari , Koike Kotaro , Hayashi Neisei , Koike Yasuhiro , Mizuno Yosuke , Nakamura Kentaro
Published: June 2016

We studied the dependence of the Brillouin frequency shift (BFS) on the water-absorption ratio in poly(methyl methacrylate)-based polymer optical fibers (POFs) to clarify the effect of the humidity on POF-based Brillouin sensors. The BFS, deduced indirectly using an ultrasonic pulse-echo technique, decreased monotonically as the water absorption ratio increased, mainly because of the decrease in the Young's modulus. For the same water absorption ratio, the BFS change was larger at a higher temperature. The maximal BFS changes (absolute values) at 40, 60, and 80 °C were 158, 285, and 510 MHz, respectively (corresponding to the temperature changes of ∼9 °C, ∼16 °C, and ∼30 °C). Thus, some countermeasure against the humidity is indispensable in implementing strain/temperature sensors based on Brillouin scattering in POFs, especially at a higher temperature. On the other hand, Brillouin-based distributed humidity sensors might be developed by exploiting the BFS dependence on water absorption in POFs.
Characteristics of toroidal rotation and ion temperature pedestals between ELM bursts in KSTAR H-mode plasmas
Authors: Ko S. H. , Kwon J. M. , Ko W. H. , Kim S. S. , Jhang H. , Terzolo L.
Published: June 2016

Steep pedestal profiles of ion temperature (Ti) and toroidal rotation (Vϕ) are routinely observed in neutral beam injection (NBI)-heated KSTAR H-mode plasmas [W. H. Ko et al., Nucl. Fusion 55, 083013 (2015)]. In this work, we report a result of detailed analysis of pedestal characteristics. By analyzing a set of data with different experimental conditions, we show that Ti and Vϕ pedestals are coupled to each other and correlation between them becomes stronger when NBI-torque is lower. This suggests the existence of intrinsic toroidal torque in the pedestal. Based on a 1D transport analysis, we find that the prevalence of residual micro-turbulences is necessary to explain momentum transport in the pedestal. The estimated strength of intrinsic torque is shown to be comparable to that from a 2.7 MW NBI source. Finally, we show that non-diffusive momentum flux is indispensable to explain momentum transport in the pedestal, and a residual stress model fits the observed momentum flux reasonably.
Verification of BOUT++ by the method of manufactured solutions
Authors: Dudson B. D. , Madsen J. , Omotani J. , Hill P. , Easy L. , Løiten M.
Published: June 2016

BOUT++ is a software package designed for solving plasma fluid models. It has been used to simulate a wide range of plasma phenomena ranging from linear stability analysis to 3D plasma turbulence and is capable of simulating a wide range of drift-reduced plasma fluid and gyro-fluid models. A verification exercise has been performed as part of a EUROfusion Enabling Research project, to rigorously test the correctness of the algorithms implemented in BOUT++, by testing order-of-accuracy convergence rates using the Method of Manufactured Solutions (MMS). We present tests of individual components including time-integration and advection schemes, non-orthogonal toroidal field-aligned coordinate systems and the shifted metric procedure which is used to handle highly sheared grids. The flux coordinate independent approach to differencing along magnetic field-lines has been implemented in BOUT++ and is here verified using the MMS in a sheared slab configuration. Finally, we show tests of three complete models: 2-field Hasegawa-Wakatani in 2D slab, 3-field reduced magnetohydrodynamics (MHD) in 3D field-aligned toroidal coordinates, and 5-field reduced MHD in slab geometry.
The general dielectric tensor for bi-kappa magnetized plasmas
Authors: Gaelzer R. , Ziebell L. F. , Meneses A. R.
Published: June 2016

In this paper, we derive the dielectric tensor for a plasma containing particles described by an anisotropic superthermal (bi-kappa) velocity distribution function. The tensor components are written in terms of the two-variables kappa plasma special functions, recently defined by Gaelzer and Ziebell [Phys. Plasmas 23, 022110 (2016)]. We also obtain various new mathematical properties for these functions, which are useful for the analytical treatment, numerical implementation, and evaluation of the functions and, consequently, of the dielectric tensor. The formalism developed here and in the previous paper provides a mathematical framework for the study of electromagnetic waves propagating at arbitrary angles and polarizations in a superthermal plasma.
Confinement time of electron plasma approaching magnetic pumping transport limit in small aspect ratio C-shaped torus
Authors: Lachhvani Lavkesh , Pahari Sambaran , Goswami Rajiv , Bajpai Manu , Yeole Yogesh , Chattopadhyay P. K.
Published: June 2016

A long confinement time of electron plasma, approaching magnetic pumping transport limit, has been observed in SMARTEX-C (a small aspect ratio partial torus with Ro/a∼1.59). Investigations of the growth rate reveal that they are governed by instabilities like resistive wall destabilization, ion driven instabilities, and electron-neutral collisions. Successful confinement of electron plasmas exceeding >1×105 poloidal E→×B→ rotations lasting for nearly 2.1±0.1 s is achieved by suppressing these instabilities. The confinement time has been estimated in two ways: (a) from the frequency scaling of the linear diocotron mode launched from sections of the wall that are also used as capacitive probes and (b) by dumping the plasma onto a charge collector at different hold times.
Line graphs for a multiplex network
Authors: Criado Regino , Flores Julio , García del Amo Alejandro , Romance Miguel , Barrena Eva , Mesa Juan A.
Published: June 2016

It is well known that line graphs offer a good summary of the graphs properties, which make them easier to analyze and highlight the desired properties. We extend the concept of line graph to multiplex networks in order to analyze multi-plexed and multi-layered networked systems. As these structures are very rich, different approaches to this notion are required to capture a variety of situations. Some relationships between these approaches are established. Finally, by means of some simulations, the potential utility of this concept is illustrated.
Generation of heavy ion beams using femtosecond laser pulses in the target normal sheath acceleration and radiation pressure acceleration regimes
Authors: Petrov G. M. , McGuffey C. , Thomas A. G. R. , Krushelnick K. , Beg F. N.
Published: June 2016

Theoretical study of heavy ion acceleration from sub-micron gold foils irradiated by a short pulse laser is presented. Using two dimensional particle-in-cell simulations, the time history of the laser pulse is examined in order to get insight into the laser energy deposition and ion acceleration process. For laser pulses with intensity 3×1021 W/cm2, duration 32 fs, focal spot size 5 μm, and energy 27 J, the calculated reflection, transmission, and coupling coefficients from a 20 nm foil are 80%, 5%, and 15%, respectively. The conversion efficiency into gold ions is 8%. Two highly collimated counter-propagating ion beams have been identified. The forward accelerated gold ions have average and maximum charge-to-mass ratio of 0.25 and 0.3, respectively, maximum normalized energy 25 MeV/nucleon, and flux 2×1011 ions/sr. An analytical model was used to determine a range of foil thicknesses suitable for acceleration of gold ions in the radiation pressure acceleration regime and the onset of the target normal sheath acceleration regime. The numerical simulations and analytical model point to at least four technical challenges hindering the heavy ion acceleration: low charge-to-mass ratio, limited number of ions amenable to acceleration, delayed acceleration, and high reflectivity of the plasma. Finally, a regime suitable for heavy ion acceleration has been identified in an alternative approach by analyzing the energy absorption and distribution among participating species and scaling of conversion efficiency, maximum energy, and flux with laser intensity.
Control of sawtooth via ECRH on EAST tokamak
Authors: Yuan Yi , Hu Liqun , Xu Liqing , Wang Xiaoguang , Wang Xiaojie , Xu Handong , Luo Zhengping , Chen Kaiyun , Lin Shiyao , Duan Yanmin , Chang Pengxiang , Zhao Hailin , He Kaiyang , Liang Yunfeng
Published: June 2016

Localized electron heating produced by electron cyclotron resonant heating (ECRH) system has been proven to be powerful tools for controlling sawtooth instabilities, because such system allows to directly modify the local plasma parameters that determine the evolution of sawtooth periods. In this paper, we present the experimental results carried out on experimental advanced superconducting tokamak (EAST) with regard to sawtooth period control via ECRH. The electron cyclotron heating system on EAST was capable of inject electron cyclotron wave toward certain locations inside or outside q = 1 magnetic surface on the poloidal cross section, which renders us able to investigate the evolution of sawtooth period against the ECRH deposition position. It is found that when ECRH deposition position is inside the q = 1 surface, the sawtooth oscillation is destabilized (characterized by reduced sawtooth period). So far, inside the q = 1 surface, there are not enough EAST experiment data that can reveal more detailed information about the relation between ECRH deposition position and sawtooth period. When ECRH deposition is outside the q = 1 surface, the sawtooth oscillation is stabilized (characterized by prolonged sawtooth period), and the sawtooth periods gradually decrease as ECRH deposition position sweeps away from q = 1 surface. The sawtooth periods reach maximum when ECRH deposition position falls around q = 1 surface. The magnetic shear at q = 1 surface is calculated to offer insights for the temporal evolution of sawtooth. The result has been found consistent with the Porcelli model.
Study of source access resistance at direct current quiescent points for AlGaN/GaN heterostructure field-effect transistors
Authors: Yang Ming , Lv Yuanjie , Feng Zhihong , Lin Wei , Cui Peng , Liu Yan , Fu Chen , Lin Zhaojun
Published: June 2016

The AlGaN/GaN heterostructure field-effect transistor (HFET) with 100 nm gate length was fabricated. An improved method is proposed to determine the value of the source access resistance corresponding to each direct current quiescent points in the saturation region of the current-voltage characteristics. The increase in the source access resistance with drain-source current has been studied, taking into account several main scattering mechanisms, including polarization Coulomb field (PCF) scattering, polar-optical-phonon scattering, piezoelectric scattering, and interface roughness scattering. It is found that PCF scattering plays a very important role in the source access resistance of AlGaN/GaN HFETs. The PCF scattering component of source access resistance decreases with the increase in drain-source current.
Morphological plasticity of bacteria—Open questions
Authors: Shen Jie-Pan , Chou Chia-Fu
Published: June 2016

Morphological plasticity of bacteria is a cryptic phenomenon, by which bacteria acquire adaptive benefits for coping with changing environments. Some environmental cues were identified to induce morphological plasticity, but the underlying molecular mechanisms remain largely unknown. Physical and chemical factors causing morphological changes in bacteria have been investigated and mostly associated with potential pathways linked to the cell wall synthetic machinery. These include starvation, oxidative stresses, predation effectors, antimicrobial agents, temperature stresses, osmotic shock, and mechanical constraints. In an extreme scenario of morphological plasticity, bacteria can be induced to be shapeshifters when the cell walls are defective or deficient. They follow distinct developmental pathways and transform into assorted morphological variants, and most of them would eventually revert to typical cell morphology. It is suggested that phenotypic heterogeneity might play a functional role in the development of morphological diversity and/or plasticity within an isogenic population. Accordingly, phenotypic heterogeneity and inherited morphological plasticity are found to be survival strategies adopted by bacteria in response to environmental stresses. Here, microfluidic and nanofabrication technology is considered to provide versatile solutions to induce morphological plasticity, sort and isolate morphological variants, and perform single-cell analysis including transcriptional and epigenetic profiling. Questions such as how morphogenesis network is modulated or rewired (if epigenetic controls of cell morphogenesis apply) to induce bacterial morphological plasticity could be resolved with the aid of micro-nanofluidic platforms and optimization algorithms, such as feedback system control.
Optical transitions in GaNAs quantum wells with variable nitrogen content embedded in AlGaAs
Authors: Elborg M. , Noda T. , Mano T. , Sakuma Y.
Published: June 2016

We investigate the optical transitions of GaNxAs1−x quantum wells (QWs) embedded in wider band gap AlGaAs. A combination of absorption and emission spectroscopic techniques is employed to systematically investigate the properties of GaNAs QWs with N concentrations ranging from 0 – 3%. From measurement of the photocurrent spectra, we find that besides QW ground state and first excited transition, distinct increases in photocurrent generation are observed. Their origin can be explained by N-induced modifications in the density of states at higher energies above the QW ground state. Photoluminescence experiments reveal that peak position dependence with temperature changes with N concentration. The characteristic S-shaped dependence for low N concentrations of 0.5% changes with increasing N concentration where the low temperature red-shift of the S-shape gradually disappears. This change indicates a gradual transition from impurity picture, where localized N induced energy states are present, to alloying picture, where an impurity-band is formed. In the highest-N sample, photoluminescence emission shows remarkable temperature stability. This phenomenon is explained by the interplay of N-induced energy states and QW confined states.
The screening effects of the screened exchange hybrid functional in surface systems: A case study on the CO/Pt(111) problem
Authors: Li H. , Gillen R. , Robertson J.
Published: June 2016

The screened exchange (sX) hybrid functional has been widely used in computational material science. Although it has widely been studied in bulk systems, less is known about its functional behavior in surface systems which are crucial to many technologies such as materials synthesis and nano-electronic devices. Assessing the screening dependent functional behaviors in the surface systems is therefore important for its application in such systems. In this work, we investigate the screening effects of the sX in CO adsorption on Pt(111) surface. The differences between the sX and Heyd-Scuseria-Ernzerhof (HSE06) hybrid functionals, and the effects of screening parameters are studied. The screening has two effects: first, the HOMO-LUMO gap is screening dependent. This affects the site preference most significantly. In this work, atop adsorption of CO/Pt(111) is predicted by the hybrid functionals with screened exchange potential. The sX(1.44) gives the largest HOMO-LUMO gap for the isolated CO molecule. The adsorption energy difference between the atop and fcc site is also the largest by the sX(1.44) which is explained by the reduced metal d states to the CO 2π* state back-donation, with stronger effect for the fcc adsorption than for the atop adsorption; second, the adsorption energy is screening dependent. This can be seen by comparing the sX(2.38) and HSE06 which have different screening strengths. They show similar surface band structures for the CO adsorption but different adsorption energies, which is explained by the stronger CO 5σ state to the metal d states donation or the effectively screened Pauli repulsion. This work underlines the screening strength as a main difference between sX and HSE06, as well as an important hybrid functional parameter for surface calculation.
Tuning the electronic properties at the surface of BaBiO3 thin films
Authors: Ferreyra C. , Guller F. , Marchini F. , Lüders U. , Albornoz C. , Leyva A. G. , Williams F. J. , Llois A. M. , Vildosola V. , Rubi D.
Published: June 2016

The presence of 2D electron gases at surfaces or interfaces in oxide thin films remains a hot topic in condensed matter physics. In particular, BaBiO3 appears as a very interesting system as it was theoretically proposed that its (001) surface should become metallic if a Bi-termination is achieved (Vildosola et al., PRL 110, 206805 (2013)). Here we report on the preparation by pulsed laser deposition and characterization of BaBiO3 thin films on silicon. We show that the texture of the films can be tuned by controlling the growth conditions, being possible to stabilize strongly (100)-textured films. We find significant differences on the spectroscopic and transport properties between (100)-textured and non-textured films. We rationalize these experimental results by performing first principles calculations, which indicate the existence of electron doping at the (100) surface. This stabilizes Bi ions in a 3+ state, shortens Bi-O bonds and reduces the electronic band gap, increasing the surface conductivity. Our results emphasize the importance of surface effects on the electronic properties of perovskites, and provide strategies to design novel oxide heterostructures with potential interface-related 2D electron gases.
Generic technique to grow III-V semiconductor nanowires in a closed glass vessel
Authors: Li Kan , Xing Yingjie , Xu H. Q.
Published: June 2016

Crystalline III-V semiconductor nanowires have great potential in fabrication of nanodevices for applications in nanoelectronics and optoelectronics, and for studies of novel physical phenomena. Sophisticated epitaxy techniques with precisely controlled growth conditions are often used to prepare high quality III-V nanowires. The growth process and cost of these experiments are therefore dedicated and very high. Here, we report a simple but generic method to synthesize III-V nanowires with high crystal quality. The technique employs a closed evacuated tube vessel with a small tube carrier containing a solid source of materials and another small tube carrier containing a growth substrate inside. The growth of nanowires is achieved after heating the closed vessel in a furnace to a preset high temperature and then cooling it down naturally to room temperature. The technique has been employed to grow InAs, GaAs, and GaSb nanowires on Si/SiO2 substrates. The as-grown nanowires are analyzed by SEM, TEM and Raman spectroscopy and the results show that the nanowires are high quality zincblende single crystals. No particular condition needs to be adjusted and controlled in the experiments. This technique provides a convenient way of synthesis of III-V semiconductor nanowires with high material quality for a wide range of applications.
Elastic-plastic analysis near the crack surface region on a mode III crack under a pair of point forces
Authors: Huang Feng , Yi Zhijian , Gu Jianyi , He Xiaobing , Zhao Chaohua , Li Ya
Published: June 2016

The crack line analysis method is used to obtain the near-crack-surface stress field of a mode III crack loaded by a pair of anti-plane point forces in an elastic-perfectly plastic material, which expands the research method from the crack line region to the crack surface region. The stresses in the plastic region, the length of the plastic region, and the geometry of the elastic-plastic boundary near the surface area of the crack are obtained analytically. Further, the maximum value of size of the plastic region along the surface of the crack is obtained. The results are sufficiently precise near the surface area of the crack, as the usual small-scale yielding condition has been given up in the analysis.
Observation of strong reflection of electron waves exiting a ballistic channel at low energy
Authors: Vaz Canute I. , Liu Changze , Campbell Jason P. , Ryan Jason T. , Southwick Richard G. , Gundlach David , Oates Anthony S. , Huang Ru , Cheung Kin. P.
Published: June 2016

Wave scattering by a potential step is a ubiquitous concept. Thus, it is surprising that theoretical treatments of ballistic transport in nanoscale devices, from quantum point contacts to ballistic transistors, assume no reflection even when the potential step is encountered upon exiting the device. Experiments so far seem to support this even if it is not clear why. Here we report clear evidence of coherent reflection when electron wave exits the channel of a nanoscale transistor and when the electron energy is low. The observed behavior is well described by a simple rectangular potential barrier model which the Schrodinger’s equation can be solved exactly. We can explain why reflection is not observed in most situations but cannot be ignored in some important situations. Our experiment also represents a direct measurement of electron injection velocity - a critical quantity in nanoscale transistors that is widely considered not measurable.
Major Histocompatibility Complex Class II in the red-tailed phascogale (Phascogale calura)
Authors: Hermsen Eden M. , Young Lauren J. , Old Julie M.
Published: June 2016

Diversity in major histocompatibility complex (MHC) genes can be correlated with the level of immunological fitness of an individual or group of individuals. This study tested published primer sets designed to amplify fragments of the MHC Class II DAB and DBB genes to amplify the equivalent gene fragments in red-tailed phascogales (Phascogale calura). Seventeen genomic DNA samples extracted from phascogale muscle tissue were used to amplify the initial DAB and DBB fragments; however, only DAB PCR proved successful. The fragments were 172 bp in length between the primers and had a high level of identity to other known marsupial MHC Class II DAB gene sequences (89–98%), including those of the koala (Phascolarctos cinereus), Tasmanian devil (Sarcophilus harrisii), common brushtail possum (Trichosurus vulpecula) and several wallaby species. Multiple sequence alignment revealed limited variability of MHC Class II genes between the individuals, but eight individual sequences in total. Genomic DNA was subsequently extracted from three fresh red-tailed phascogale scat samples and DAB fragments successfully amplified. The technique will allow for red-tailed phascogales to be sampled non-invasively in the wild and to determine the level of MHC diversity among individuals in the population.
Molecular Electrostatic Potential-Based Atoms in Molecules: Shielding Effects and Reactivity Patterns
Authors: Kumar Anmol , Gadre Shridhar R.
Published: June 2016

The Atoms in Molecules (AIM) concept based on the zero-flux surface (ZFS) of the gradient of molecular electrostatic potential (MESP) has been recently proposed by the present authors. The nature of MESP-based atomic basins brings out the asymmetric electronic distribution in a molecule. An electron-rich atom among the two bonded atoms is seen to possess a completely closed MESP-based atomic basin. The present article illustrates the nature of atomic basins for a variety of molecules such as BF, BH3, AlCl3, B2H6, and Al2Cl6, and a Lewis acid–base pair, viz. NH3BH3 wherein the electronic distribution is not merely guided by difference in the electronegativity of the atoms. The study also explores some transition metal complexes, viz. Ni(CO)4, Fe(CO)5, Cr(CO)6, Mn2(CO)10, Co2(CO)8, Fe(η5-C5H5)2, Co(η3-C3H5), and Co(η3-C3H5)(CO)3, which show a similar phenomenon of intricate charge transfer among the ligands and the metal centre. The present article employs MESP-based AIM for a qualitative explanation of the shielding or deshielding effects revealed by NMR data as well as susceptibility of an atomic region towards an electrophilic or nucleophilic attack. Because the topographical features of MESP and thus the nature of atomic basins are not very sensitive to the level of theory and basis set, the present article demonstrates the capability of MESP as a consistent and simple tool for the portrayal of asymmetry in molecular charge distribution.
Aproximaciones desde la ética en la interpretación en casos de violencia de género
Authors: Valero-Garcés Carmen
Published: June 2016

A 2011 Gender Violence Macrosurvey carried out by the Centro de Investigaciones Sociológicas (CIS, Spanish Centre for Sociological Research) in collaboration with the Spanish Government alerts The Macro on Gender Violence conducted by the Sociological Research Centre (CIS) gives significant figures on gender-based violence (GBV) suffered by foreign women in Spain. Based on the specificity of care for foreign women in issues of gender based violence (GBV) and taking as its starting point previous investigations by FITISPOs, the recommendations and work carried out within the European project SOS VICS and my own experience, the main aim of this article is twofold: first, to draw attention to qualitative aspects of the interactions between service providers, interpreters and foreign victims of gender based violence ( GBV), and secondly, to, investigate what happens when some ethical dilemmas come up between the different professionals that take care of GBV.
Understanding translation universals
Authors: Zasiekin Serhii
Published: June 2016

Translation S- and T-universals have been widely discussed in Translation Studies and their psycholinguistic study has been among the priority topics today. The article is focused on the study of translation ‘S- universals’ (Chesterman 2004) and is based both on the psycholinguistic model of literary translation, which combines today’s neuroscience theories of cognitivism and connectionism, and on the experimental data that demonstrate its validity. The model is resulted in a series of experiments held with undergraduate students of translation department.
The results of the study proved the idea of existing specific procedural and discursive S-universals in literary translation. As the empirical data showed, these universals maintain the status of common strategies depending on translator’s cognitive style (analytical or synthetic) and his dominant channel (visual, auditory, kinesthetic) of source text perception.
Somatic embryogenesis and direct as well as indirect organogenesis inLilium pumilumDC. Fisch., an endangered ornamental and medicinal plant
Authors: Zhang Jing , Gai MeiZhu , Li XueYan , Li TianLai , Sun HongMei
Published: June 2016

Somatic embryogenesis and organogenesis in Lilium pumilum were successfully regulated by picloram, α-naphthaleneacetic acid (NAA), and 6-benzyladenine (BA). In organogenesis, the highest shoot regeneration frequency (92.5%) was obtained directly from bulb scales on Murashige and Skoog (MS) medium containing 2.0 mg L−1 BA and 0.2 mg L−1 NAA, while organogenic callus (OC) formed from leaves on MS medium supplemented with 1.0 mg L−1 BA and 0.5 mg L−1 NAA. Following subculture, 76.7% of OC regenerated shoots. In somatic embryogenesis, the combination of picloram and NAA increased the amount of embryogenic callus (EC) that formed with a maximum on 90.7% of all explants which formed 11 somatic embryos (SEs) per explant. Differences between EC and OC in cellular morphology and cell differentiation fate were easily observed. SEs initially formed via an exogenous or an endogenous origin. The appearance of a protoderm in heart-shaped SE and the bipolar shoot–root development in oval-shaped SE indicated true somatic embryogenesis. This protocol provides a new and detailed regulation and histological examination of regeneration pattern in L. pumilum.