bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel ratiometric dual-emission fluorescence magnetic nanohybrid for HIgG immunoassay
Authors: Xia Tingting , Ma Qiang , Li Yang , Yan Xu , Su Xingguang
Published: June 2016

The proposed ratiometric dual-emission (carbon dots and QDs) fluorescence magnetic nanohybrid displayed excellent analytical performance for the detection of HIgG.
Hydrothermal synthesis of two supramolecular inorganic–organic hybrid phosphomolybdates based on Ni(ii) and Co(ii) ions: structural diversity and heterogeneous catalytic activities
Authors: Paul Luna , Dolai Malay , Panja Anangamohan , Ali Mahammad
Published: June 2016

Two new compounds (NHEPH2)5[NiII(P4Mo6O31)2]·6H2O (1) and {(NHEPH2)2[CoII(H2O)6]}[P2Mo5O23]·2H2O (2) exhibited heterogeneous styrene oxidation by H2O2 under mild conditions.
Replacing a single atom accelerates the folding of a protein and increases its thermostability
Authors: Arnold Ulrich , Raines Ronald T.
Published: June 2016

The conformational attributes of proline can have a substantial effect on the folding of polypeptide chains into a native structure and on the stability of that structure.
Biaxially extended thiophene–isoindigo donor–acceptor conjugated polymers for high-performance flexible field-effect transistors
Authors: Wu Hung-Chin , Hong Chian-Wen , Chen Wen-Chang
Published: June 2016

Biaxially-extended thiophene–isoindigo donor–acceptor conjugated polymers were explored for high-performance flexible field-effect transistors. A charge carrier mobility of 1.0 cm2 V−1 s−1 was achieved under ambient atmosphere with stable electrical properties.
Correction: Fluorescent core–shell nanoparticles and nanocapsules using comb-like macromolecular RAFT agents: synthesis and functionalization thereof
Authors: Grazon Chloé , Rieger Jutta , Beaunier Patricia , Méallet-Renault Rachel , Clavier Gilles
Published: June 2016

Correction for ‘Fluorescent core–shell nanoparticles and nanocapsules using comb-like macromolecular RAFT agents: synthesis and functionalization thereof’ by Chloé Grazon, et al., Polym. Chem., 2016, DOI: 10.1039/c6py00646a.
Macroscopic porous MnO2 aerogels for supercapacitor electrodes
Authors: Xu Kongliang , Zhu Xuedong , She Ping , Shang Yinxing , Sun Hang , Liu Zhenning
Published: June 2016

Supercapacitor electrodes fabricated from macroscopic porous MnO2 aerogels have demonstrated enhanced specific capacitance, high rate capability and excellent cycling durability.
Full alignment of dispersed colloidal nanorods by alternating electric fields
Authors: Mohammadimasoudi M. , Hens Z. , Neyts K.
Published: June 2016

The parallel alignment of an ensemble of colloidal nanorods may unleash their application as the optically anisotropic constituent in polarized fluorescent sheets or polarization-selective detectors.
Synthesis of CuO/ZnO/Al2O3/ZrO2/CeO2 nanocatalysts via homogeneous precipitation and combustion methods used in methanol steam reforming for fuel cell grade hydrogen production
Authors: Talkhoncheh Saeed Khajeh , Haghighi Mohammad , Minaei Shahab , Ajamein Hossein , Abdollahifar Mozaffar
Published: June 2016

In this research the effects of synthesis method and CeO2 and ZrO2 promoters were studied in the steam reforming of methanol over a CuO/ZnO/Al2O3 nanocatalyst. Addition of ZrO2 and CeO2 reduces CO selectivity, while CeO2 is more effective.
Graphene–polyglycerol–curcumin hybrid as a near-infrared (NIR) laser stimuli-responsive system for chemo-photothermal cancer therapy
Authors: Bani Farhad , Adeli Mohsen , Movahedi Soodabeh , Sadeghizadeh Majid
Published: June 2016

The aim of this study is to develop a nano graphene–polyglycerol–curcumin hybrid capable of simultaneous co-delivery of chemotherapeutic drug and cytotoxic heat to cancer cells by near infrared (NIR) laser irradiation.
Blue-emitting and amphibious metal (Cu, Ni, Pt, Pd) nanodots prepared within supramolecular polymeric micellesfor cellular imaging applications
Authors: Shi Yunfeng , Zhao Junhong , Zhou Linzhu , Li Ting , Liu Mei , Liu Leilei
Published: June 2016

We propose a new method for the preparation of blue-emitting and amphibious metal (Cu, Ni, Pt, Pd) nanodots using supramolecular polymeric micelle nanoreactors ​for cellular imaging applications.
A hexameric peptide purified from Styela plicata protects against free radical-induced oxidative stress in cells and zebrafish model
Authors: Ko Seok-Chun , Kim Eun-A , Jung Won-Kyo , Kim Won-Suk , Lee Seung-Cheol , Son Kwang-Tae , Kim Jae-Il , Jeon You-Jin
Published: June 2016

To prepare antioxidative peptide from Styela plicata, nine proteases were employed for enzymatic hydrolysis, and the antioxidative activities of the hydrolysates were investigated using an electron spin resonance (ESR) spectrometer.
Bismuth sulfide nanoflowers as high performance near-infrared laser detectors and visible-light-driven photocatalysts
Authors: Chao Junfeng , Xing Shumin , Zhao Jianzhou , Qin Changhai , Duan Degong , Zhao Yuliang , He Qiang
Published: June 2016

Bi2S3 nanoflowers flexible laser detector.
Dimensional tailoring of nitrogen-doped graphene for high performance supercapacitors
Authors: Lee Seung Yong , Choi Chang Hyuck , Chung Min Wook , Chung Jae Hoon , Woo Seong Ihl
Published: June 2016

In supercapacitors, one dimensional graphene ribbons which form net-like porous structure demonstrate low mass transfer resistance at low frequency region and a consequent efficient charge transferability.
Effects of LAGP electrolyte on suppressing polysulfide shuttling in Li–S cells
Authors: Wu Xue-ling , Zong Jun , Xu Han , Wang Wei , Liu Xing-jiang
Published: June 2016

In this work, the solid electrolyte of Li1.5Al0.5Ge1.5(PO4)3 (LAGP) is used to suppress polysulfides shuttling in Li–S cells.
Flavans with cytotoxic activity from the stem and root bark of Daphne giraldii
Authors: Sun Qian , Li Fei-Fei , Wang Di , Wu Jie , Yao Guo-Dong , Li Xue , Li Ling-Zhi , Liu Qing-Bo , Huang Xiao-Xiao , Song Shao-Jiang
Published: June 2016

Thirteen new flavan compounds named daphnegiravans A–M (1–13) and eight known analogues (14–21) were isolated from the stem and root bark of Daphne giraldii. Further cytotoxicity investigation was conducted on 3 and 9–12.
Photophysical properties of di-Schiff bases: evaluating the synergistic effect of non-covalent interactions and alkyl spacers in enhanced emissions of solids
Authors: Das Moyna , Baig Fayaz , Sarkar Madhushree
Published: June 2016

Di-Schiff bases with alkyl spacer (ethyl, butyl and hexyl) showed enhanced light emitting properties in solid state, while quenching was observed for di-Schiff bases with hydrazine spacer. Packing of the molecules via non covalent interactions along with the flexible spacer played the role in dictating the emission properties.
Silicon dioxide molecular sieve with mono-layer carbon deposited in the channels and carbon nanotubes on the outside for lithium–sulfur batteries
Authors: Jia Lei , Li Huiyu , Zhu Wentao , Qiu Xinping
Published: June 2016

A novel sulfur host matrix prepared by the deposition of mono-layer carbon into silicon dioxide molecular sieve channels and carbon nanotubes on the molecular sieve surface is proposed as an electrode material for lithium sulfur batteries.
Preparation of a preferentially oriented SAPO-34 membrane by secondary growth under microwave irradiation
Authors: Bing Liancheng , Wang Guangjian , Wang Fang , Liu Xiufeng , Zhang Baoquan
Published: June 2016

A preferentially oriented SAPO-34 membrane with no large defects was prepared on an oriented SAPO-34 seed layer by secondary hydrothermal microwave growth.
A novel approach to the fabrication of bleached shellac by a totally chlorine-free (TCF) bleaching method
Authors: Li Kun , Zheng Hua , Zhang Hong , Zhang Wen-wen , Li Kai , Xu Juan
Published: June 2016

A novel approach to fabricate bleached shellac was established by totally chlorine-free (TCF) bleached process and a unique TCF bleached shellac, excellent material for food or medicine industry, was obtained firstly in alkaline condition.
Evolution of the reaction mechanism during the MTH induction period over the 2-dimensional FER zeolite
Authors: Qi Liang , Li Jinzhe , Xu Lei , Liu Zhongmin
Published: June 2016

During the MTH reaction over HZSM-35, the dual-cycle mechanism was found to evolve evidently as the induction reaction progressed.
Highly emissive, naked-eye solvatochromic probe based on styryl tetrahydrodibenzo[a,i]phenanthridine for acidochromic applications
Authors: Balijapalli Umamahesh , Manickam Saravanakumar , Thiyagarajan Manojkumar Dhanthalu , Iyer Sathiyanarayanan Kulathu
Published: June 2016

A new series of 5-styryl tetrahydrodibenzo[a,i]phenanthridines was readily synthesized from β-tetralone, ammonium acetate and cinnamaldehydes and successfully applied to quantitatively detect pH in biological fluids and acid impurities in solvents.
Molecular nanocapsule-decorated porous monolith: preparation and elimination of cationic dyes from water
Authors: Hu Ruoxi , Wan Decheng , Jin Ming
Published: June 2016

A reverse-micelle-like dendritic amphiphile can directly lead to a porous adsorbent with the pores carboxyl-functionalized.
α,β-Substituent effect of dialkylphosphinic acids on lanthanide extraction
Authors: Du Ruobing , Yu Donghai , An Huaying , Zhang Suhui , Lu Renjie , Zhao Gang , Xiao Ji-Chang
Published: June 2016

The calculational first stability equilibrium constants and experimental extraction equilibrium constants are similar in trend. And the simplified model was used to explore the metal–ligand interactions and effect of alkyl-substituent on extraction.
Optical-electric properties of poly(amic acid) composite films with a low content of thermotropic liquid crystals
Authors: Ding Ling , Zhang Yihe , Liu Leipeng , Hu Jianshe , Lv Fengzhu
Published: June 2016

Poly(amic acid) composite films with the thermotropic liquid crystal, 10-cholesteroxy-10-oxocaproic acid (COOA) were developed.
Liquid marble containing degradable polyperoxides for adhesion force-changeable pressure-sensitive adhesives
Authors: Sato Eriko , Yuri Michihiro , Fujii Syuji , Nishiyama Takashi , Nakamura Yoshinobu , Horibe Hideo
Published: June 2016

Non-stick liquid marbles containing a sticky polyperoxide ​provide a strong stick and dismantlability depending on external stimuli.
Zn-catalyzed hydrohydrazination of propargylamides with BocNHNH2: a novel entry into the 1,2,4-triazine core
Authors: Lukin Alexey , Vedekhina Tatiana , Tovpeko Dmitry , Zhurilo Nikolay , Krasavin Mikhail
Published: June 2016

Hydrohydrazination of propargylamides with BocNHNH2under Zn(OTf)2catalysis gave dihydro-1,2,4-triazines which can be efficiently aromatizedin situwith K3[Fe(CN)6]. This provides a new entry into the medicinally important 1,2,4-triazine core.
Back and forth invasion in the interaction of Turing and Hopf domains in a reactive microemulsion system
Authors: Berenstein Igal , Carballido-Landeira Jorge
Published: June 2016

Pattern formation is studied numerically for a reactive microemulsion when two parts of the system with different droplet fractions are initially put into contact.
Understanding problems of lithiated anodes in lithium oxygen full-cells
Authors: Kwak Won-Jin , Shin Hyeon-Ji , Reiter Jakub , Tsiouvaras Nikolaos , Hassoun Jusef , Passerini Stefano , Scrosati Bruno , Sun Yang-Kook
Published: June 2016

Ambiguously unsolved problems in lithium oxygen full-cells were intensively investigated. The formation of LiOH at the anode side causes continuous loss of the Li+ ions, and thus results in decreased potential and poor cycling of the Li–O2 full-cell.
Uncovering the prominent role of metal ions in octahedral versus tetrahedral sites of cobalt–zinc oxide catalysts for efficient oxidation of water
Authors: Menezes Prashanth W. , Indra Arindam , Bergmann Arno , Chernev Petko , Walter Carsten , Dau Holger , Strasser Peter , Driess Matthias
Published: June 2016

The tremendous impact of tetrahedralversusoctahedral metal sites on the superior electrocatalytic performance of ZnCo2O4for the oxygen evolution reaction has been elucidated through comprehensive analysis of bulk and near-surface structures.
Stretchable supercapacitor based on a cellular structure
Authors: He Sisi , Cao Jingyu , Xie Songlin , Deng Jue , Gao Qiang , Qiu Longbin , Zhang Jing , Wang Lie , Hu Yajie , Peng Huisheng
Published: June 2016

A new stretchable supercapacitor is discovered by designing the electrode in a cellular architecture mimicking nature.
Integrating cobalt phosphide and cobalt nitride-embedded nitrogen-rich nanocarbons: high-performance bifunctional electrocatalysts for oxygen reduction and evolution
Authors: Zhong Xing , Jiang Yu , Chen Xianlang , Wang Lei , Zhuang Guilin , Li Xiaonian , Wang Jian-guo
Published: June 2016

Co2P and CoxN nanoparticles embedded nitrogen-rich nanocarbons were fabricated, serving as high-performance bifunctional electrocatalysts for oxygen reduction and evolution.
Dual phosphorescent dinuclear transition metal complexes, and their application as triplet photosensitizers for TTA upconversion and photodynamic therapy
Authors: Wang Junsi , Lu Yue , McGoldrick Niamh , Zhang Caishun , Yang Wenbo , Zhao Jianzhang , Draper Sylvia M.
Published: June 2016

A long-lived dual phosphorescence triplet photosensitiser: for TTA upconversion and PDT.
Investigating the Impact of Flap Overdesign on Viability
Authors: Aherrera Andrew , Pincus David , Vernadakis Adam
Published: June 2016

Background Partial or complete flap necrosis is a detrimental outcome complicating reconstructive surgery. The purpose of this study was to evaluate the impact of flap overdesign on viability in the rat model.

Methods Forty Sprague-Dawley rats were equally divided into four groups receiving flaps of varying length-to-width ratios: 2:1, 3:1, 4:1, and 5:1. All animals had caudally based, modified McFarlane-style flap created. Areas of survival were assessed 14 days postoperatively and compared among groups using one-way analysis of variance.

Results The mean areas of flap survival were 8.0 ± 0.0 cm2, 7.8 ± 1.1 cm2, 8.3 ± 1.1 cm2, and 8.1 ± 1.5 cm2 for the 2:1, 3:1, 4:1, and 5:1 length-to-width ratio groups, respectively. There were no statistically significant differences in mean areas of flap survival among groups (p > 0.05).

Conclusion Flap overdesign does not increase the risk of flap necrosis in a random-pattern flap.
Low-threshold terahertz molecular laser optically pumped by a quantum cascade laser
Authors: Pagies A. , Ducournau G. , Lampin J.-F.
Published: June 2016

We demonstrate a low-threshold, compact, room temperature, and continuous-wave terahertz molecular laser optically pumped by a mid-infrared quantum cascade laser. These characteristics are obtained, thanks to large dipole transitions of the active medium: NH3 (ammonia) in gas state. The low-power (<60 mW) laser pumping excites the molecules, thanks to intense mid-infrared transitions around 10.3 μm. The molecules de-excite by stimulated emission on pure inversion “umbrella-mode” quantum transitions allowed by the tunnel effect. The tunability of the quantum cascade laser gives access to several pure inversion transitions with different rotation states: we demonstrate the continuous-wave generation of ten laser lines around 1 THz. At 1.07 THz, we measure a power of 34 μW with a very low-threshold of 2 mW and a high differential efficiency of 0.82 mW/W. The spectrum was measured showing that the linewidth is lower than 1 MHz. To our knowledge, this is the first THz molecular laser pumped by a solid-state source and this result opens the way for compact, simple, and efficient THz source at room temperature for imaging applications.
Invited Article: Broadband highly efficient dielectric metadevices for polarization control
Authors: Kruk Sergey , Hopkins Ben , Kravchenko Ivan I. , Miroshnichenko Andrey , Neshev Dragomir N. , Kivshar Yuri S.
Published: June 2016

Metadevices based on dielectric nanostructured surfaces with both electric and magnetic Mie-type resonances have resulted in the best efficiency to date for functional flat optics with only one disadvantage: a narrow operational bandwidth. Here we experimentally demonstrate broadband transparent all-dielectric metasurfaces for highly efficient polarization manipulation. We utilize the generalized Huygens principle, with a superposition of the scattering contributions from several electric and magnetic multipolar modes of the constituent meta-atoms, to achieve destructive interference in reflection over a large spectral bandwidth. By employing this novel concept, we demonstrate reflectionless (∼90% transmission) half-wave plates, quarter-wave plates, and vector beam q-plates that can operate across multiple telecom bands with ∼99% polarization conversion efficiency.
Switching 70Pb(Mg1/3Nb2/3)O3-0.30PbTiO3 single crystal by 3 MHz bipolar field
Authors: Li Shiyang , Chen Zhaojiang , Cao Wenwu
Published: June 2016

Polarization switching and associated electromechanical property changes at 3.0 MHz were investigated with and without a direct current (dc) bias for [001]c poled 0.70Pb(Mg1/3Nb2/3)O3-0.30PbTiO3 single crystal. The results showed that the coercive field under a bipolar pulse at 3.0 MHz is 2.75 times as large as conventional defined Ec (2.58 kV/cm at 0.1 Hz), and a dc bias can further enlarge the driving field. Our results point to an innovative transducer operating mechanism at high frequencies since one could drive the crystal under much larger fields at high frequencies to produce much stronger signals from a small array element for deeper penetration imaging.
Investigation of ablation of thin foil aluminum ribbon array at 1.5 MA
Authors: Ye Fan , Li Zhenghong , Chen Faxin , Xue Feibiao , Meng Shijian , Ning Jiamin , Qin Yi , Hu Qingyuan , Jiang Shuqing , Li Linbo , Chu Yanyun , Yang Jianlun , Xu Rongkun , Xu Zeping
Published: June 2016

We present experimental studies of initiation and ablation of a thin foil aluminum ribbon array at the 1.5 MA current level. In contrast to the previous work, we employ ribbon arrays with different ribbon gap parameters to investigate how this affects plasma initiation and foil ablation. Gated narrowband ultraviolet imaging indicated that the current was disorderly distributed at early period of discharge. But later on, it became axially stable and azimuthally symmetrical even for load with a gap as small as 0.1 mm. Using magnetic field probes installed inside and outside the array, we also observed that precursor current at positions with a distance of less than 2.7 mm to the central axis for 4-mm-radius arrays decreased when ribbon gap became small. Results of 0.2 mm gap ribbon array showed an evidence that ribbons can be merged. These observations imply that thin foil ribbon arrays may have potential applications in z-pinch experiments on large scale pulsed power facilities.
Derivation of the Hall and extended magnetohydrodynamics brackets
Authors: D'Avignon Eric C. , Morrison Philip J. , Lingam Manasvi
Published: June 2016

There are several plasma models intermediate in complexity between ideal magnetohydrodynamics (MHD) and two-fluid theory, with Hall and Extended MHD being two important examples. In this paper, we investigate several aspects of these theories, with the ultimate goal of deriving the noncanonical Poisson brackets used in their Hamiltonian formulations. We present fully Lagrangian actions for each, as opposed to the fully Eulerian, or mixed Eulerian-Lagrangian, actions that have appeared previously. As an important step in this process, we exhibit each theory's two advected fluxes (in analogy to ideal MHD's advected magnetic flux), discovering also that with the correct choice of gauge they have corresponding Lie-dragged potentials resembling the electromagnetic vector potential, and associated conserved helicities. Finally, using the Euler-Lagrange map, we show how to derive the noncanonical Eulerian brackets from canonical Lagrangian ones.
Lineshape spectroscopy with a very high resolution, very high signal-to-noise crystal spectrometer
Authors: Beiersdorfer P. , Magee E. W. , Brown G. V. , Chen H. , Emig J. , Hell N. , Bitter M. , Hill K. W. , Allan P. , Brown C. R. D. , Hill M. P. , Hoarty D. J. , Hobbs L. M. R. , James S. F.
Published: June 2016

We have developed a high-resolution x-ray spectrometer for measuring the shapes of spectral lines produced from laser-irradiated targets on the Orion laser facility. The instrument utilizes a spherically bent crystal geometry to spatially focus and spectrally analyze photons from foil or microdot targets. The high photon collection efficiency resulting from its imaging properties allows the instrument to be mounted outside the Orion chamber, where it is far less sensitive to particles, hard x-rays, or electromagnetic pulses than instruments housed close to the target chamber center in ten-inch manipulators. Moreover, Bragg angles above 50° are possible, which provide greatly improved spectral resolution compared to radially viewing, near grazing-incidence crystal spectrometers. These properties make the new instrument an ideal lineshape diagnostic for determining plasma temperature and density. We describe its calibration on the Livermore electron beam ion trap facility and present spectral data of the K-shell emission from highly charged sulfur produced by long-pulse as well as short-pulse beams on the Orion laser in the United Kingdom.
Nonlinear electromagnetic formulation for particle-in-cell simulation of lower hybrid waves in toroidal geometry
Authors: Bao J. , Lin Z. , Kuley A. , Wang Z. X.
Published: June 2016

An electromagnetic particle simulation model has been formulated and verified for nonlinear processes of lower hybrid (LH) waves in fusion plasmas. Electron dynamics are described by the drift kinetic equation using either kinetic momentum or canonical momentum. Ion dynamics are treated as the fluid system or by the Vlasov equation. Compressible magnetic perturbation is retained to simulate both the fast and slow LH waves. Numerical properties are greatly improved by using the electron continuity equation to enforce the consistency between electrostatic potential and vector potential, and by using the importance sampling scheme. The simulation model has been implemented in the gyrokinetic toroidal code (GTC), and verified for the dispersion relation and nonlinear particle trapping of the electromagnetic LH waves.
Theoretical study of alignment dynamics of magnetic oblate spheroids in rotating magnetic fields
Authors: Tan Mingyang , Song Han , Dhagat Pallavi , Jander Albrecht , Walker Travis W.
Published: June 2016

Magnetic composites containing anisotropic magnetic particles can achieve properties not possible in corresponding bulk or thin films of the magnetic material. In this work, we discuss how planar magnetic anisotropy may be achieved in a composite by aligning disk-shaped particles in an in-plane rotating magnetic field. Previous efforts have reported a simple model of aligning particles in a high-frequency rotating magnetic field. However, no complete analytic solution was proposed. Here, we provide a full analytic solution that describes the alignment dynamics of microdisks in a rotating field that covers the entire frequency range. We also provide simplified solutions at both high-frequency and low-frequency limits through asymptotic expansions for easy implementation into industrial settings. The analytic solution is confirmed by numerical simulation and shows agreement with experiments.
Spike-like solitary waves in incompressible boundary layers driven by a travelling wave
Authors: Feng Peihua , Zhang Jiazhong , Wang Wei
Published: June 2016

Nonlinear waves produced in an incompressible boundary layer driven by a travelling wave are investigated, with damping considered as well. As one of the typical nonlinear waves, the spike-like wave is governed by the driven-damped Benjamin–Ono equation. The wave field enters a completely irregular state beyond a critical time, increasing the amplitude of the driving wave continuously. On the other hand, the number of spikes of solitary waves increases through multiplication of the wave pattern. The wave energy grows in a sequence of sharp steps, and hysteresis loops are found in the system. The wave energy jumps to different levels with multiplication of the wave, which is described by winding number bifurcation of phase trajectories. Also, the phenomenon of multiplication and hysteresis steps is found when varying the speed of driving wave as well. Moreover, the nature of the change of wave pattern and its energy is the stability loss of the wave caused by saddle-node bifurcation.
Analysis of radial and longitudinal field of plasma wakefield generated by a Laguerre-Gauss laser pulse
Authors: Firouzjaei Ali Shekari , Shokri Babak
Published: June 2016

In the present paper, we study the wakes known as the donut wake which is generated by Laguerre-Gauss (LG) laser pulses. Effects of the special spatial profile of a LG pulse on the radial and longitudinal wakefields are presented via an analytical model in a weakly non-linear regime in two dimensions. Different aspects of the donut-shaped wakefields have been analyzed and compared with Gaussian-driven wakes. There is also some discussion about the accelerating-focusing phase of the donut wake. Variations of longitudinal and radial wakes with laser amplitude, pulse length, and pulse spot size have been presented and discussed. Finally, we present the optimum pulse duration for such wakes.
Laser pulse driven terahertz generation via resonant transition radiation in inhomogeneous plasmas
Authors: Miao Chenlong , Palastro John P. , Antonsen Thomas M.
Published: June 2016

An intense, short laser pulse propagating across a plasma boundary ponderomotively drives THz radiation. Full format PIC simulations and theoretical analysis are conducted to investigate the properties of this radiation. Simulation results which show the THz emission originates in regions of varying density and covers a broad spectrum with maximum frequency close to the maximum plasma frequency. In the case of a sharp vacuum-plasma boundary, the radiation is generated symmetrically at the plasma entrance and exit, and its properties are independent of plasma density when the density exceeds a characteristic value determined by the product of the plasma frequency and the laser pulse duration. For a diffuse vacuum-plasma boundary, the emission from the plasma entrance and exit is asymmetric: increasing and decreasing density ramps enhance and diminish the radiated energy, respectively. Enhancements by a factor of 50 are found and simulations show that a 1.66 J, 50 fs driver pulse can generate ∼400 μJ of THz radiation in a 1.2 mm increasing density ramp. We present a model that attributes this effect to a plasma resonance process in the density ramp. The results from the model match those of the simulations for ramp lengths less than 600 μm. For longer ramps for which simulations are too time consuming, the model shows that the amount of radiation reaches a maximum at a ramp length determined by collisional absorption.
Properties of a large volume glow discharge helium plasma by measuring the broadband microwave phase shift in different pressures
Authors: Gao Ruilin , Yuan Chengxun , Liu Sha , Yue Feng , Jia Jieshu , Zhou Zhong-xiang , Wu Jian , Li Hui
Published: June 2016

A novel type of large cylindrical glow discharge helium plasma with a 50 cm diameter and a 40 cm thickness is presented, which is powered by dual reticular electrodes under an AC source with frequency 20 kHz. Microwave characteristics are studied using vector network analyzer with two broadband antennae ranging from 2 GHz to 18 GHz to measure the phase shift. The phase shift under varying gas pressure is used to calculate the electron density ne, which varies from 2.36 × 1016 m−3 to 11.2 × 1016 m−3 under different discharge conditions. The measured results provide a method to diagnose helium plasma with large volume, high pressure, and high collision rate, especially for the condition which the probe is not suitable.
Development of the radial neutron camera system for the HL-2A tokamak
Authors: Zhang Y. P. , Yang J. W. , Liu Yi , Fan T. S. , Luo X. B. , Yuan G. L. , Zhang P. F. , Xie X. F. , Song X. Y. , Chen W. , Ji X. Q. , Li X. , Du T. F. , Ge L. J. , Fu B. Z. , Isobe M. , Song X. M. , Shi Z. B. , Yang Q. W. , Duan X. R.
Published: June 2016

A new radial neutron camera system has been developed and operated recently in the HL-2A tokamak to measure the spatial and time resolved 2.5 MeV D-D fusion neutron, enhancing the understanding of the energetic-ion physics. The camera mainly consists of a multichannel collimator, liquid-scintillation detectors, shielding systems, and a data acquisition system. Measurements of the D-D fusion neutrons using the camera have been successfully performed during the 2015 HL-2A experiment campaign. The measurements show that the distribution of the fusion neutrons in the HL-2A plasma has a peaked profile, suggesting that the neutral beam injection beam ions in the plasma have a peaked distribution. It also suggests that the neutrons are primarily produced from beam-target reactions in the plasma core region. The measurement results from the neutron camera are well consistent with the results of both a standard 235U fission chamber and NUBEAM neutron calculations. In this paper, the new radial neutron camera system on HL-2A and the first experimental results are described.
Ferroelectric BiFeO3 thin-film optical modulators
Authors: Zhu Minmin , Du Zehui , Liu Qing , Chen Bensong , Tsang Siu Hon , Teo Edwin Hang Tong
Published: June 2016

High quality epitaxial BiFeO3 (BFO) thin films have been grown on (001) SrTiO3 substrate by magnetron sputtering. Both a-axis and c-axis BFO orientations were studied. Prism coupler results reveal that the c-axis and a-axis refractive indices of the BFO thin films were 2.721 and 2.653 at 632.8 nm; the corresponding propagation losses were 4.3 and 4.6 dB/cm, respectively. An electro-optic (EO) modulator based on such BFO film has been demonstrated with a fast switching time t = 3.8 μs at 632.8 nm for the a-axis orientation and t = 3.4 μs for the c-axis orientation. Moreover, these BFO films gave the Pockels coefficient reff = 19.3 pm/V for the c-axis orientation and reff = 15.9 pm/V for the a-axis orientation at 632.8 nm. Such an anisotropic refractive index and linear EO behaviors are attributed to the epitaxial strain and stripe domain structure in the BFO thin films with mixed phases. This study illustrates the suitability of the BFO thin films for EO modulators and optical switches beyond their current extensive spintronic and memory applications.
Spin Seebeck effect in a weak ferromagnet
Authors: Arboleda Juan David , Arnache Olmos Oscar , Aguirre Myriam Haydee , Ramos Rafael , Anadon Alberto , Ibarra Manuel Ricardo
Published: June 2016

We report the observation of room temperature spin Seebeck effect (SSE) in a weak ferromagnetic normal spinel Zinc Ferrite (ZFO). Despite the weak ferromagnetic behavior, the measurements of the SSE in ZFO show a thermoelectric voltage response comparable with the reported values for other ferromagnetic materials. Our results suggest that SSE might possibly originate from the surface magnetization of the ZFO.
Composite media for high density heat assisted magnetic recording
Authors: Liu Zengyuan , Jiao Yipeng , Victora R. H.
Published: June 2016

A heat assisted magnetic recording composite media with a superparamagnetic writing layer is proposed. The recording process is initiated in the write layer that is magnetically softer than the long term storage layer. Upon cooling, the composite structure copies the information from the writing layer to the lower Curie temperature (Tc) storage layer, e.g., doped FePt. The advantages include insensitivity to Tc variance in the storage layer, and thus the opportunity to significantly lower the FePt Tc without the resulting Tc distribution adversely affecting the performance. The composite structure has a small jitter within 0.1 nm of the grain size limit owing to the sharp transition width of the optimized superparamagnetic writing layer. The user density of the composite structure can reach 4.7  Tb/in.2 for a Gaussian heat spot with a full-width-at-half-maximum of 30 nm, a 12 nm reader width, and an optimized bit length of 6 nm.
Impact of layer and substrate properties on the surface acoustic wave velocity in scandium doped aluminum nitride based SAW devices on sapphire
Authors: Gillinger M. , Shaposhnikov K. , Knobloch T. , Schneider M. , Kaltenbacher M. , Schmid U.
Published: June 2016

This paper investigates the performance of surface acoustic wave (SAW) devices consisting of reactively sputter deposited scandium doped aluminum nitride (ScxAl1-xN) thin films as piezoelectric layers on sapphire substrates for wireless sensor or for RF-MEMS applications. To investigate the influence of piezoelectric film thickness on the device properties, samples with thickness ranging from 500 nm up to 3000 nm are fabricated. S21 measurements and simulations demonstrate that the phase velocity is predominantly influenced by the mass density of the electrode material rather than by the thickness of the piezoelectric film. Additionally, the wave propagation direction is varied by rotating the interdigital transducer structures with respect to the crystal orientation of the substrate. The phase velocity is about 2.5% higher for a-direction compared to m-direction of the sapphire substrate, which is in excellent agreement with the difference in the anisotropic Young's modulus of the substrate corresponding to these directions.
Superiority of terahertz over infrared transmission through bandages and burn wound ointments
Authors: Suen Jonathan Y. , Padilla Willie J.
Published: June 2016

Terahertz electromagnetic waves have long been proposed to be ideal for spectroscopy and imaging through non-polar dielectric materials that contain no water. Terahertz radiation may thus be useful for monitoring burn and wound injury recovery, as common care treatments involve application of both a clinical dressing and topical ointment. Here, we investigate the optical properties of typical care treatments in the millimeter wave (150–300 GHz), terahertz (0.3–3 THz), and infrared (14.5–0.67 μm) ranges of the electromagnetic spectrum. We find that THz radiation realizes low absorption coefficients and high levels of transmission compared to infrared wavelengths, which were strongly attenuated. Terahertz imaging can enable safe, non-ionizing, noninvasive monitoring of the healing process directly through clinical dressings and recovery ointments, minimizing the frequency of dressing changes and thus increasing the rate of the healing process.
Dynamics of electroforming and electrically driven insulator-metal transition in NbOx selector
Authors: Park Jaehyuk , Cha Euijun , Karpov Ilya , Hwang Hyunsang
Published: June 2016

In this research, we investigate an electroforming and electrically driven insulator-metal transition (E-IMT) characteristic of the NbOx film that follows the framework of nucleation theory. First, we carry out the electroforming process to form the crystalline NbO2 phase, and it separated to nucleation and grain-growth according to external electric field degree. During the electroforming process, we also study the field-induced nucleation that occurred selectively according to the crystallinity of films. We conclude that the E-IMT process was the result of Peierls transition between the tetragonal and the rutile NbO2 phases, and we experimentally deduce the minimum energy pathway for transition.
Polarization gating of high harmonic generation in the water window
Authors: Li Jie , Ren Xiaoming , Yin Yanchun , Cheng Yan , Cunningham Eric , Wu Yi , Chang Zenghu
Published: June 2016

We implement the polarization gating (PG) technique with a two-cycle, 1.7 μm driving field to generate an attosecond supercontinuum extending to the water window spectral region. The ellipticity dependence of the high harmonic yield over a photon energy range much broader than previous work is measured and compared with a semi-classical model. When PG is applied, the carrier-envelope phase (CEP) is swept to study its influence on the continuum generation. PG with one-cycle (5.7 fs) and two-cycle (11.3 fs) delay are tested, and both give continuous spectra spanning from 50 to 450 eV under certain CEP values, strongly indicating the generation of isolated attosecond pulses in the water window region.
Impact of vicinal GaAs(001) substrates on Bi incorporation and photoluminescence in molecular beam epitaxy-grown GaAs1−xBix
Authors: Li Jincheng , Collar Kristen , Jiao Wenyuan , Kong Wei , Kuech Thomas F. , Babcock Susan E. , Brown April
Published: June 2016

The controlled incorporation of Bi into GaAs is a key challenge to synthesizing dilute Bi materials. This work reveals the importance of the surface step density and direction on Bi incorporation. Steps in the [110] direction are demonstrated to enhance Bi incorporation, but at the cost of reduced photoluminescence intensity at a red-shifted peak position, while steps in the [1¯10] direction yield the opposite behavior. A qualitative model based on the competitive incorporation of As and Bi at different step edges is used to rationalize the observed differences in Bi incorporation.
Depicting how Eucalyptus globulus survives drought: involvement of redox and DNA methylation events
Authors: Correia Barbara , Valledor Luis , Hancock Robert D. , Jesus Cláudia , Amaral Joana , Meijón Mónica , Pinto Glória
Published: June 2016

Eucalyptus globulus Labill. is widely cultivated and used by industry but its productivity is currently restricted by drought events, so research focussing on supporting programs to breed adapted germplasm is needed. In the present work we monitored severity of acute drought stress (7 and 11 days after water withholding) and relief (2h and 3 days after rewatering) by quantifying several biochemical markers of oxidative stress and DNA methylation patterns in leaves. Water withholding imposed a mild oxidative stress as estimated by redox shifts in the major antioxidant pools and increased lipid peroxidation. At the DNA level, global 5-methylcytosine distribution increased over the dehydration period especially in vascular tissue as estimated by immunolocalisation. Using methylation-sensitive RAPD analysis, which discriminates methylation changes occurring in specific DNA sequences, we found a high number of specific demethylation events also taking place. Immunolocalisation indicated a rapid reduction in global DNA methylation 2h after rehydration; however, a large number of de novo methylation events were still detected by methylation-sensitive RAPD. These events were associated with decreased lipid peroxidation and high cellular GSH pools relative to unstressed plants. Our results indicate the parallel induction of redox and complex DNA methylation changes occurring during stress imposition and relief.
Pedogenic and lithogenic gravels as indicators of soil polygenesis in the Brazilian Cerrado
Authors: Zinn Yuri L. , Bigham Jerry M.
Published: June 2016

Although particles >2 mm are not considered soil material, gravels composed of resistant secondary minerals can be useful records of past soil environments. We investigated gravels (2–8 mm) from a Plinthic Haplustox in central Brazil in order to assess their composition, fabric and genesis. Gravels were initially grouped into six macromorphological types, and investigated by mineralogical, micromorphological and microprobe analyses. The results suggest that gravels can be classified as pedogenic or lithopedogenic. Pedogenic gravels comprise indurated soil materials and include black magnetic gravels, black non-magnetic gravels and red earthy gravels. Magnetic gravels contained mostly quartz, hematite and magnetite–maghemite and were poor in kaolinite, gibbsite and goethite, whereas non-magnetic and red earthy gravels had the same minerals as in the surrounding soil. Lithopedogenic gravels are fragments of resistant rocks impregnated by iron (Fe), aluminium (Al) and manganese (Mn) oxides, including platy shales, quartzites and coarse quartz. The latter two showed oxide impregnations around internal pores, whereas the shale fragments included considerable mica, which contributed illite and potassium to the soil clays and, thus, the pedogenic gravels. These results point to multiple cycles of formation and incorporation of cemented materials into the soil, as well as their later impregnation by Fe, Mn and Al oxides. Thus, the conventional classification of all such gravels as ‘ironstone’ is questionable, and their potential role as indicators of past and present soil environments is demonstrated, which deserves further investigation.
The repeated spherical indentation test: an efficient way to evaluate the adhesion of hard coatings
Authors: Qiu L. , Zhu X. , He G. , Xu K.
Published: June 2016

Fatigue failure of hard coatings usually occurs at much lower loads than failure under static loading. Hence one way to evaluate coating adhesion should be cyclic loading close to service conditions. In this study, a new method of adhesion measurement for hard coatings is introduced based on interfacial fatigue under repeated indentation. Mono- and multi-layered coatings with different interfacial states are evaluated by a repeated-indentation test. Detachment of the coatings occurs initially at the rim of the indenter imprint, apparently as a result of adhesive failure. In contrast to monolayer coatings, peeling of multilayer coatings depends on the lowest strength of the interfaces. This study also demonstrates that the adhesion determined by the repeated-indentation test is sensitive to the interfacial state, allowing an optimised or weakened interface to be clearly revealed.
Body politics and legitimacy: towards a feminist epistemology of the Egyptian revolution
Authors: Sorbera Lucia
Published: June 2016

In this essay, I discuss political legitimacy from a feminist perspective, analysing the experience of women political activists in Egypt. Building on Linda Alcoff's work on memory, testimony and decolonizing epistemology, my analysis focusses on two intertwined issues: women's political representation and the public debate about sexual harassment. Data collected by Egyptian feminist organizations reveal that, after one century of women's political participation and 60 years after universal suffrage, the gender gap remains wide. Furthermore, both feminist and human rights organizations denounce that authoritarian regimes use sexual harassment to intimidate democratic activists. Although the right to equal political participation has been a main concern for the Egyptian feminists since 1923, the achievement of universal suffrage in 1956 did not provide a viable solution to the gender gap in Egypt, and women are still fighting to find a way out from the binary co-optation/exclusion. Significantly, as I discuss in this essay, women political activists are the main targets of harassment. In addition, women in general and discourses about sexual violence and sexual morality remain highly controversial in Egypt.
Tapping out a mechanical code for T cell triggering
Authors: Dustin Michael L. , Kam Lance C.
Published: June 2016

Mechanical forces play increasingly recognized roles in T cell receptor (TCR) signal transduction. Hu and Butte (2016. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201511053) demonstrate that actin is required for T cells to generate forces at the TCR and that exogenous application of force can emulate these cytoskeletal forces and trigger T cell activation.
Stem-cell research and regenerative medicine in China
Authors: Qiu Jane
Published: June 2016

For stem-cell researchers around the world, 2015 was a roller-coaster year. In April, Junjiu Huang, a biologist at the Sun Yat-sen University in Guangzhou, published the first paper on gene editing in human embryos with CRISPR-cas9. This sparked a global controversy—with many Western media using this as an example of China's lack of ethical standards. Subsequent discussions, which culminated in the summit in Washington, DC, last December, have eased the anxieties to some extent over this study and similar studies have now been proposed or approved in the UK and Sweden. Surprisingly, according to Nature magazine (the same magazine publishing some of the news reports on this study), Huang was one of the 10 scientists in the world that made a difference last year.

In a forum chaired by National Science Review's Executive Associate Editor Mu-ming Poo, stem-cell researchers and a bioethicist discussed how they see last year's furore over gene editing, why China should streamline its oversight and regulatory processes, and where the future of the country's stem-cell research and regenerative medicine lies.

Duanqing Pei

Stem-cell researcher and Director General of Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, in Guangzhou

Xiaomei Zhai

Bioethicist and Executive Director of the Centre for Bioethics, Peking Union Medical College, in Beijing

Qi Zhou

Stem-cell researcher at the Institute of Zoology, Chinese Academy of Sciences, in Beijing

Jianhong Zhu

Neurosurgeon and neuroscientist at Huashan Hospital, Fudan University, in Shanghai

Mu-ming Poo (Chair)

Neuroscientist and Director of the Institute of Neuroscience, Chinese Academy of Sciences, in Shanghai
Composition of Proteins Extracted from Two Species of Leguminous Bauhinia Grains
Authors: Siwela Muthulisi , Amonsou Eric O.
Published: June 2016

There is a growing demand for alternative protein sources for industrial applications. Bauhinia are underutilized protein‐rich oilseed legumes primarily grown as ornamental plants. In this study, the composition and structure of proteins extracted from two Bauhinia species, B. galpinii and B. petersiana, were determined in comparison with soya bean. Albumin and globulin (75%) were the major storage proteins of Bauhinia. Albumin content of B. galpinii was substantially high (28%), about twice those of soya and B. petersiana. Bauhinia grains were good sources of lysine (approximately 4 g/100 g of protein). By SDS‐PAGE, Bauhinia proteins showed three major protein bands ranging from 17,000 to 76,000 for both species. Only one subunit (17,000) of the basic glycinin (11S) seemed to be present in Bauhinia compared with soya. Bauhinia proteins had more β‐sheet conformation (42%) than α‐helix (22%). Bauhinia grains may provide a new opportunity of protein for industrial applications.
Arabidopsis Proline Dehydrogenase Contributes to Flagellin-Mediated PAMP-Triggered Immunity by Affecting RBOHD
Authors: Fabro Georgina , Rizzi Yanina Soledad , Alvarez María Elena
Published: June 2016

Plants activate different defense systems to counteract the attack of microbial pathogens. Among them, the recognition of conserved microbial- or pathogen-associated molecular patterns (MAMPs or PAMPs) by pattern-recognition receptors stimulates MAMP- or PAMP-triggered immunity (PTI). In recent years, the elicitors, receptors, and signaling pathways leading to PTI have been extensively studied. However, the contribution of organelles to this program deserves further characterization. Here, we studied how processes altering the mitochondrial electron transport chain (mETC) influence PTI establishment. With particular emphasis, we evaluated the effect of proline dehydrogenase (ProDH), an enzyme that can load electrons into the mETC and regulate the cellular redox state. We found that mETC uncouplers (antimycin or rotenone) and manganese superoxide dismutase deficiency impair flg22-induced responses such as accumulation of reactive oxygen species (ROS) and bacterial growth limitation. ProDH mutants also reduce these defenses, decreasing callose deposition as well. Using ProDH inhibitors and ProDH inducers (exogenous Pro treatment), we showed that this enzyme modulates the generation of ROS by the plasma membrane respiratory burst NADPH oxidase homolog D. In this way, we contribute to the understanding of mitochondrial activities influencing early and late PTI responses and the coordination of the redox-associated mitochondrial enzyme ProDH with defense events initiated at the plasma membrane.