bluuebunny/crossref_metadata_2025 huggingface dataset:
A Bi2Te3@CoNiMo composite as a high performance bifunctional catalyst for hydrogen and oxygen evolution reactions
Authors: Yin K. , Cui Z. D. , Zheng X. R. , Yang X. J. , Zhu S. L. , Li Z. Y. , Liang Y. Q.
Published: September 2015

Renewable hydrogen generated by using solar energy has attracted increasing interest in energy conversion.
Magnetically driven Bi2O3/BiOCl-based hybrid microrobots for photocatalytic water remediation
Authors: Mushtaq Fajer , Guerrero Miguel , Sakar Mahmut Selman , Hoop Marcus , Lindo André M. , Sort Jordi , Chen Xiangzhong , Nelson Bradley J. , Pellicer Eva , Pané Salvador
Published: September 2015

Hybrid microstructures consisting of a CoNi segment for wireless magnetic manipulation coupled to a Bi2O3/BiOCl segment are utilized for water remediation.
Effect of pyrolysis pressure on activity of Fe–N–C catalysts for oxygen reduction
Authors: Gumeci Cenk , Leonard Nathaniel , Liu Yuanchao , McKinney Samuel , Halevi Barr , Barton Scott Calabrese
Published: September 2015

In the synthesis of Fe–N–C catalysts by high-pressure pyrolysis, higher precursor loading increases gas-phase pressure and enhances nitrogen retention, active site density and ORR activity.
Anion-effects on electrochemical properties of ionic liquid electrolytes for rechargeable aluminum batteries
Authors: Wang Huali , Gu Sichen , Bai Ying , Chen Shi , Zhu Na , Wu Chuan , Wu Feng
Published: September 2015

Anion-effects are embodied in: (1) halogen anions resulting from different halogenated imidazole salt species, which is the critical factor for electrochemical windows; (2) aluminum chloride anions resulting from different AlCl3/imidazole salt mole ratios, which is the determinant of electrochemical activities.
Dendrite growth in the recharging process of zinc–air batteries
Authors: Wang Keliang , Pei Pucheng , Ma Ze , Chen Huicui , Xu Huachi , Chen Dongfang , Wang Xizhong
Published: September 2015

Zinc dendrite growth is controlled by electrolyte flow at high current densities, effectively extending the cycle life of rechargeable zinc–air batteries.
Use of a protic salt for the formation of liquid-crystalline proton-conductive complexes with mesomorphic diols
Authors: Yamashita Akihiro , Yoshio Masafumi , Soberats Bartolome , Ohno Hiroyuki , Kato Takashi
Published: September 2015

Co-assembly of an imidazolium-based protic salt and wedge-shaped mesomorphic diols forms 1D and 2D proton transport pathways.
Shell-thickness dependent electron transfer and relaxation in type-II core–shell CdS/TiO2 structures with optimized photoelectrochemical performance
Authors: Han Sancan , Pu Ying-Chih , Zheng Lingxia , Zhang Jin Zhong , Fang Xiaosheng
Published: September 2015

Shell-thickness dependent charge carrier dynamics and enhanced photoelectrochemical performance were studied in uniform core–shell CdS/TiO2 composites.
A novel 3D ZnO/Cu2O nanowire photocathode material with highly efficient photoelectrocatalytic performance
Authors: Bai Jing , Li Yunpo , Wang Rui , Huang Ke , Zeng Qingyi , Li Jinhua , Zhou Baoxue
Published: September 2015

A 3D ZnO/Cu2O nanowire photocathode that largely improves photoelectrocatalytic performance was synthesized using a simple, cost-effective solution processed growth method.
The role of ligand–receptor interactions in visual detection of HepG2 cells using a liquid crystal microdroplet-based biosensor
Authors: Choi Yuri , Lee Kyubae , Gupta Kailash C. , Park Soo-Young , Kang Inn-Kyu
Published: September 2015

Optical (a) and polarized (b) micrographs showing orientational transition in a LC microdroplet on contacting with a HepG2 cell in PBS solution.
o-Carborane derivatives for probing molecular polarity effects on liquid crystal phase stability and dielectric behavior
Authors: Pecyna Jacek , Jankowiak Aleksandra , Pociecha Damian , Kaszyński Piotr
Published: September 2015

A series of mesogenic derivatives ofo-carborane was synthesized, their properties were analyzed by thermal, optical and XRD methods, and results were compared with those of isostructuralp-carborane and benzene analogues.
Amphotropic azobenzene derivatives with oligooxyethylene and glycerol based polar groups
Authors: Tan Xiaoping , Zhang Ruilin , Guo Chunxiang , Cheng Xiaohong , Gao Hongfei , Liu Feng , Bruckner Johanna R. , Giesselmann Frank , Prehm Marko , Tschierske Carsten
Published: September 2015

Amphiphilic azobenzenes self-assemble into double layer smectic and hexagonal columnar liquid crystalline phases, which are modified by protic solvents and light irradiation.
Formation and local conduction of nanopits in BiFeO3 epitaxial films
Authors: Zhao Yajuan , Yin Zhigang , Zhang Xingwang , Fu Zhen , Wu Jinliang
Published: September 2015

Nanopits are formed in BiFeO3 epilayers and enhanced conductance, governed by interface-regulated Poole–Frenkel emission, occurs at the nanopits.
Spatially optimized quaternary phosphine oxide host materials for high-efficiency blue phosphorescence and thermally activated delayed fluorescence organic light-emitting diodes
Authors: Ding Dongxue , Zhang Zhen , Wei Ying , Yan Pengfei , Xu Hui
Published: September 2015

Spatial optimization of host materials for highly efficient blue organic light-emitting diodes was rationally performed on the basis of a series of ternary and quaternary phosphine oxide materials.
Indene-1,3-dionemethylene-4H-pyran derivatives containing alkoxy chains of various lengths: aggregation-induced emission enhancement, mechanofluorochromic properties and solvent-induced emission changes
Authors: Liu Yanze , Lei Yunxiang , Li Fei , Chen Jiuxi , Liu Miaochang , Huang Xiaobo , Gao Wenxia , Wu Huayue , Ding Jinchang , Cheng Yixiang
Published: September 2015

Indene-1,3-dionemethylene-4H-pyran derivatives exhibiting alkoxy-chain-length-dependent optical properties.
A new level of regulation in gluconeogenesis: metabolic state modulates the intracellular localization of aldolase B and its interaction with liver fructose-1,6-bisphosphatase
Authors: Droppelmann Cristian A. , Sáez Doris E. , Asenjo Joel L. , Yáñez Alejandro J. , García-Rocha Mar , Concha Ilona I. , Grez Manuel , Guinovart Joan J. , Slebe Juan C.
Published: September 2015

Understanding how glucose metabolism is finely regulated at molecular and cellular levels in the liver is critical for knowing its relationship to related pathologies, such as diabetes. In order to gain insight into the regulation of glucose metabolism, we studied the liver-expressed isoforms aldolase B and fructose-1,6-bisphosphatase-1 (FBPase-1), key enzymes in gluconeogenesis, analysing their cellular localization in hepatocytes under different metabolic conditions and their protein–protein interaction in vitro and in vivo. We observed that glucose, insulin, glucagon and adrenaline differentially modulate the intracellular distribution of aldolase B and FBPase-1. Interestingly, the in vitro protein–protein interaction analysis between aldolase B and FBPase-1 showed a specific and regulable interaction between them, whereas aldolase A (muscle isozyme) and FBPase-1 showed no interaction. The affinity of the aldolase B and FBPase-1 complex was modulated by intermediate metabolites, but only in the presence of K+. We observed a decreased association constant in the presence of adenosine monophosphate, fructose-2,6-bisphosphate, fructose-6-phosphate and inhibitory concentrations of fructose-1,6-bisphosphate. Conversely, the association constant of the complex increased in the presence of dihydroxyacetone phosphate (DHAP) and non-inhibitory concentrations of fructose-1,6-bisphosphate. Notably, in vivo FRET studies confirmed the interaction between aldolase B and FBPase-1. Also, the co-expression of aldolase B and FBPase-1 in cultured cells suggested that FBPase-1 guides the cellular localization of aldolase B. Our results provide further evidence that metabolic conditions modulate aldolase B and FBPase-1 activity at the cellular level through the regulation of their interaction, suggesting that their association confers a catalytic advantage for both enzymes.
Two‐transformer‐based full‐bridge soft‐switching DC–DC converter with improved characteristics
Authors: Wu Hongfei , Chen Liqun , Xing Yan , Xiao Xi , Xu Peng
Published: September 2015

A novel two‐transformer‐based full‐bridge soft‐switching DC–DC converter is proposed. The primary‐windings of the two transformers are connected in series, while the two secondary windings of the two transformers are connected to the output through a semi‐active full‐bridge rectifier and a passive full‐bridge rectifier, respectively, in parallel. The voltage stress on the primary windings of the transformers is reduced, as well as the current stresses of the secondary windings of the transformers and the rectifying devices. Zero‐voltage‐switching is realised for the MOSFETs, while zero‐current switching is achieved for all the diodes by adopting the secondary side phase‐shift control. In comparison with existing topologies, the turn‐off current and loss of the secondary side MOSFETs are reduced, because only half of the output current flows through these switches. The circulating current is effectively suppressed, which leads to less conduction loss. The proposed converter also offers some advantages, such as smaller value and size of high‐frequency‐link inductor and reduced output current ripple. The converter can operate in the buck and boost modes to fulfil the application demands with wide input/output voltage ranges. The operating principle of the proposed converter is analysed in detail and verified with experimental results.
Cadaveric Spinal Surgery Simulation: A Comparison of Cadaver Types
Authors: Tomlinson James E. , Yiasemidou Marina , Watts Anna L. , Roberts Dave J. H. , Timothy Jake
Published: September 2015

Study Design

Single-blinded study.

Objective

To assess the suitability of three types of cadaver for simulating pedicle screw insertion and establish if there is an ideal.

Methods

Three types of cadaver—Thiel-embalmed, Crosado-embalmed, and formaldehyde-embalmed—were draped and the spines exposed. Experienced surgeons were asked to place pedicle screws in each cadaver and give written questionnaire feedback using a modified Likert scale. Soft tissue and bony properties were assessed, along with the role of simulation in spinal surgery training.

Results

The Thiel cadaver rated highest for soft tissue feel and appearance with a median score of 6 for both (range 2 to 7). The Crosado cadaver rated highest for bony feel, with a median score of 6 (range 2 to 7). The formaldehyde cadaver rated lowest for all categories with median scores of 2, 2.5, and 3.5, respectively. All surgeons felt pedicle screw insertion should be learned in a simulated setting using human cadavers.

Conclusion

Thiel and Crosado cadavers both offered lifelike simulation of pedicle screw insertion, with each having advantages depending on whether the focus is on soft tissue approach or technical aspects of bony screw insertion. Both cadaver types offer the advantage of long life span, unlike fresh frozen tissue, which means cadavers can be used multiple times, thus reducing the costs.
Moderately Degenerated Human Intervertebral Disks Exhibit a Less Geometrically Specific Collagen Fiber Orientation Distribution
Authors: Dittmar Roman , van Rijsbergen Marc M. , Ito Keita
Published: September 2015

Study Design

Collagen fiber orientation analysis in moderately degenerated human cadaveric annulus fibrosus (AF) tissue samples.

Objective

Little is known about the changes in tissue architecture during early degeneration of intervertebral disks (IVDs). As collagen organization strongly affects the disk function, the objective of this study was to quantify the AF collagen orientation and its spatial distribution in moderately degenerated IVDs (Pfirrmann grade III).

Methods

AF tissue samples were dissected from four circumferential (anterior, left and right lateral, and posterior) and two radial (outer and inner) locations. Cryosections were imaged using Second Harmonic Generation microscopy, and the collagen fiber orientations per location were determined utilizing a fiber-tracking image analysis algorithm. Also, the proportionality between the fibers aligned in the primary direction versus other oriented fibers was determined.

Results

Mean collagen fiber angles ranged between 21 and 31 degrees for outer and 15 to 19 degrees for inner AF samples. Mean collagen orientations at circumferential locations were only significantly different from each other at inner anterior and lateral location. Similarly, fiber angles between the outer and inner AF were not significantly different except at the posterior location. Fiber orientation proportionality did not show large variations. Except for a significant difference in outer AF proportionality between posterior and lateral positions, no other differences were observed.

Conclusion

The results of this study provide the first quantitative evidence that the collagen fiber orientation of moderately degenerated disks exhibits a spatial rather than homogeneous distribution and typical collagen orientation gradients characterizing healthy IVDs are only partially retained.
Patient and Procedural Factors that Influence Anesthetized, Nonoperative Time in Spine Surgery
Authors: Puffer Ross C. , Mallory Grant W. , Burrows Anthony M. , Curry Timothy B. , Clarke Michelle J.
Published: September 2015

Study Design

Retrospective study.

Objective

Efficient use of operating room time is important, as delays during induction or recovery increase time not spent operating while in the operating room. We identified factors that increase anesthetized, nonoperative time by utilizing a database of over 5,000 consecutive neurosurgical spine cases.

Methods

Surgical records were searched to identify all spine surgeries performed between January 2010 and July 2012. Anesthetized, nonoperative time was calculated from the anesthesia record and compared with both patient and procedure characteristics to determine any significant relationships

Results

There were 5,515 surgical cases with a mean age of 60.5 and mean body mass index (BMI) of 29.7; 3,226 (58%) were male subjects. There were 1,176 (21%) fusion cases, and level of pathology was predominantly lumbar (4,010 cases, 73%). Fusion cases had a significantly longer total anesthetized, nonoperative time (fusion: 98 minutes, nonfusion: 76 minutes, mean difference: 22 minutes, p < 0.0001). Significant factors affecting anesthetized, nonoperative time in nonfusion cases include age greater than 65 years (mean difference 5 minutes, p < 0.0001), American Society of Anesthesiologists (ASA) grade, and BMI (BMI < 25: 72 ± 1.2 minutes, BMI 25 to 29: 74 ± 0.6 minutes, BMI 30 to 39: 79 ± 0.6 minutes, BMI 40 + : 87 ± 1.8 minutes, p < 0.0001). Similarly, for fusion operations, age > 65 years significantly increased nonoperative time (mean difference 6 minutes, p < 0.01), as did increasing ASA (mean difference 9 minutes, p < 0.0001) and increasing BMI.

Conclusion

Patient and surgical factors, including ASA grade, BMI, level of pathology, and surgical approach, have noticeable effects on anesthetized, nonoperative times in spine surgery.
Analysis of charge-carrier diffusion in the photosensing films of HgCdTe infrared focal plane array photodetectors
Authors: Vishnyakov A. V. , Stuchinsky V. A. , Brunev D. V. , Zverev A. V. , Dvoretsky S. A.
Published: September 2015

The lateral diffusion of minority charge carriers in the photosensitive films of photovoltaic HgCdTe infrared focal plane array (IR FPA) detectors with a continuous (without mesa insulation of the diodes) absorber layer was experimentally studied and analyzed. The experimental study was performed using the spot-scan technique, implemented by scanning a narrow strip-shaped illumination spot with a selected FPA diode at various levels of diode photocurrents in the detector. The local diffusion lengths of the charge carriers in the film regions beneath and outside the FPA diodes were estimated. The values obtained for the bulk diffusion length of minority carriers in the HgCdTe material of the examined middle-wave and long-wave IR FPA detectors were found to be in good agreement with previously reported data. Moreover, the estimated local diffusion length of minority carriers in the film region beneath the back-biased photodiodes proved to be consistent with a theoretical estimate of this length.
Molecular simulation of homogeneous nucleation of crystals of an ionic liquid from the melt
Authors: He Xiaoxia , Shen Yan , Hung Francisco R. , Santiso Erik E.
Published: September 2015

The homogeneous nucleation of crystals of the ionic liquid [dmim+][Cl−] from its supercooled liquid phase in the bulk (P = 1 bar, T = 340 K, representing a supercooling of 58 K) was studied using molecular simulations. The string method in collective variables [Maragliano et al., J. Chem. Phys. 125, 024106 (2006)] was used in combination with Markovian milestoning with Voronoi tessellations [Maragliano et al., J. Chem. Theory Comput. 5, 2589–2594 (2009)] and order parameters for molecular crystals [E. E. Santiso and B. L. Trout, J. Chem. Phys. 134, 064109 (2011)] to sketch a minimum free energy path connecting the supercooled liquid and the monoclinic crystal phases, and to determine the free energy and the rates involved in the homogeneous nucleation process. The physical significance of the configurations found along this minimum free energy path is discussed with the help of calculations based on classical nucleation theory and with additional simulation results obtained for a larger system. Our results indicate that, at a supercooling of 58 K, the liquid has to overcome a free energy barrier of the order of 60 kcal/mol and to form a critical nucleus with an average size of about 3.6 nm, before it reaches the thermodynamically stable crystal phase. A simulated homogeneous nucleation rate of 5.0 × 1010 cm−3 s−1 was obtained for our system, which is in reasonable agreement with experimental and simulation rates for homogeneous nucleation of ice at similar degrees of supercooling. This study represents our first step in a series of studies aimed at understanding the nucleation and growth of crystals of organic salts near surfaces and inside nanopores.
Molecular dynamics simulations of the structure and single-particle dynamics of mixtures of divalent salts and ionic liquids
Authors: Gómez-González Víctor , Docampo-Álvarez Borja , Cabeza Oscar , Fedorov Maxim , Lynden-Bell Ruth M. , Gallego Luis J. , Varela Luis M.
Published: September 2015

We report a molecular dynamics study of the structure and single-particle dynamics of mixtures of a protic (ethylammonium nitrate) and an aprotic (1-butyl-3-methylimidazolium hexaflurophosphate [BMIM][PF6]) room-temperature ionic liquids doped with magnesium and calcium salts with a common anion at 298.15 K and 1 atm. The solvation of these divalent cations in dense ionic environments is analyzed by means of apparent molar volumes of the mixtures, radial distribution functions, and coordination numbers. For the protic mixtures, the effect of salt concentration on the network of hydrogen bonds is also considered. Moreover, single-particle dynamics of the salt cations is studied by means of their velocity autocorrelation functions and vibrational densities of states, explicitly analyzing the influence of salt concentration, and cation charge and mass on these magnitudes. The effect of the valency of the salt cation on these properties is considered comparing the results with those for the corresponding mixtures with lithium salts. We found that the main structural and dynamic features of the local solvation of divalent cations in ionic liquids are similar to those of monovalent salts, with cations being localized in the polar nanoregions of the bulk mixture coordinated in monodentate and bidentate coordination modes by the [NO3]− and [PF6]− anions. However, stronger electrostatic correlations of these polar nanoregions than in mixtures with salts with monovalent cations are found. The vibrational modes of the ionic liquid (IL) are seen to be scarcely affected by the addition of the salt, and the effect of mass and charge on the vibrational densities of states of the dissolved cations is reported. Cation mass is seen to exert a deeper influence than charge on the low-frequency vibrational spectra, giving a red shift of the vibrational modes and a virtual suppression of the higher energy vibrational modes for the heavier Ca2+ cations. No qualitative difference with monovalent cations was found in what solvation is concerned, which suggests that no enhanced reduction of the mobility of these cations and their complexes in ILs respective to those of monovalent cations is to be expected.
Generation of silicon nanocrystals by damage free continuous wave laser annealing of substrate-bound SiOx films
Authors: Fricke-Begemann T. , Wang N. , Peretzki P. , Seibt M. , Ihlemann J.
Published: September 2015

Silicon nanocrystals have been generated by laser induced phase separation in SiOx films. A continuous wave laser emitting at 405 nm is focused to a 6 μm diameter spot on 530 nm thick SiOx films deposited on fused silica substrates. Irradiation of lines is accomplished by focus scanning. The samples are investigated by atomic force microscopy, TEM, Raman spectroscopy, and photoluminescence measurements. At a laser power of 35 mW corresponding to an irradiance of about 1.2 × 105 W/cm2, the formation of Si-nanocrystals in the film without any deterioration of the surface is observed. At higher laser power, the central irradiated region is oxidized to SiO2 and exhibits some porous character, while the surface remains optically smooth, and nanocrystals are observed beside and beneath this oxidized region. Amorphous Si-nanoclusters are formed at lower laser power and around the lines written at high power.
Morphology of gas cavities on patterned hydrophobic surfaces under reduced pressure
Authors: Xue Yahui , Lv Pengyu , Liu Ying , Shi Yipeng , Lin Hao , Duan Huiling
Published: September 2015

Gas cavities trapped on structured hydrophobic surfaces play important roles in realizing functionalities such as superhydrophobicity, drag reduction, and surface cleaning. The morphology of the cavities exhibits strong dependence on system parameters which impact the performance of these surfaces. In this work, a complete theoretical analysis is presented to predict cavity morphological change under reduced liquid pressure, on a submerged hydrophobic surface patterned with cylindrical pores. Equilibrium solutions are derived for five different phases, namely, (I) pinned recession, (II) depinned recession, (III) Cassie-Baxter, (IV) expansion, and (V) coalescence; their stabilities are also analyzed. A phase map is developed outlining the different regimes with respect to the gas amount and liquid pressure. Importantly, phase (IV) exhibits a complex stability behavior that leads to two possible routes to coalescence, which lends two different mechanisms of cavitation. Accordingly, the threshold pressure for cavitation can be calculated. The theoretical model is supported by direct experimental measurements via confocal microscopy and demonstrates good quantitative accuracy. This work provides a predictive tool for the design of functional structured hydrophobic surfaces.
Performance of positive ion based high power ion source of EAST neutral beam injector
Authors: Hu Chundong , Xie Yahong , Xie Yuanlai , Liu Sheng , Xu Yongjian , Liang Lizhen , Jiang Caichao , Li Jun , Liu Zhimin
Published: September 2015

The positive ion based source with a hot cathode based arc chamber and a tetrode accelerator was employed for a neutral beam injector on the experimental advanced superconducting tokamak (EAST). Four ion sources were developed and each ion source has produced 4 MW @ 80 keV hydrogen beam on the test bed. 100 s long pulse operation with modulated beam has also been tested on the test bed. The accelerator was upgraded from circular shaped to diamond shaped in the latest two ion sources. In the latest campaign of EAST experiment, four ion sources injected more than 4 MW deuterium beam with beam energy of 60 keV into EAST.
A comprehensive physics-based model encompassing variable surface resistance and underlying physics of ionic polymer-metal composite actuators
Authors: Shen Qi , Palmre Viljar , Stalbaum Tyler , Kim Kwang J.
Published: September 2015

The ionic polymer-metal composite (IPMC) is an emerging smart material in actuation and sensing applications, such as artificial muscles, underwater actuators, and advanced medical devices. However, the effect of the change in surface electrode properties on the actuating of IPMC has not been well studied. To address this problem, we theoretically predict and experimentally investigate the dynamic electro-mechanical response of the IPMC thin-strip actuator. A model of the IPMC actuator is proposed based on the Poisson-Nernst-Planck equations for ion transport and charge dynamics in the polymer membrane, while a physical model for the change of surface resistance of the electrodes of the IPMC due to deformation is also incorporated. By incorporating these two models, a complete, dynamic, physics-based model for IPMC actuators is presented. To verify the model, IPMC samples were prepared and experiments were conducted. The results show that the theoretical model can accurately predict the actuating performance of IPMC actuators over a range of dynamic conditions. Additionally, the charge dynamics inside the polymer during the oscillation of the IPMC is presented. It is also shown that the charge at the boundary mainly affects the induced stress of the IPMC. The current study is beneficial for the comprehensive understanding of the surface electrode effect on the performance of IPMC actuators.
Large apparent slip at a moving contact line
Authors: Qian Bian , Park Joonsik , Breuer Kenneth S.
Published: September 2015

Two different particle tracking velocimetry techniques are used to measure the fluid velocities close to the substrate in the vicinity of both receding and advancing contact lines. The slip velocity is found to be as much as 60% of the substrate speed near the contact line and persists as far as 10 μm from the liquid-gas interface. The estimated slip length near the contact line singularity requires a measurement of the shear rate close the substrate which depends strongly on the spatial resolution of the measurement technique. The slip length is found to be approximately 5 μm when flood illumination is used and approximately 500 nm when total internal reflection fluorescence illumination is used.
Structure, stability, and superconductivity of new Xe–H compounds under high pressure
Authors: Yan Xiaozhen , Chen Yangmei , Kuang Xiaoyu , Xiang Shikai
Published: September 2015

Application of high pressure can substantially enhance the chemical reactivity of xenon and has recently extended the Xe-compounds to unexpected elements such as Fe and H. Using unbiased structure searching techniques combined with first-principles calculations, we predict novel compounds of stable XeH2 and XeH4, and metastable XeH, XeH3, XeH5, XeH6, XeH7, and XeH8 under high pressure. Rather than van der Waals complexes, these are weakly covalent or ionic compounds stabilized by a pressure-induced increase in charge transfer from Xe to H atoms. The calculated electronic structures with hybrid exchange-correlation functionals reveal that only XeH and XeH2 are metalized under 300 GPa. For the metallic XeH and XeH2 at certain pressures, the superconducting critical temperatures are finally studied, by using Allen-Dynes modified McMillan equation combined with the calculated electron-phonon coupling parameter.
Osmotically driven drug delivery through remote-controlled magnetic nanocomposite membranes
Authors: Zaher A. , Li S. , Wolf K. T. , Pirmoradi F. N. , Yassine O. , Lin L. , Khashab N. M. , Kosel J.
Published: September 2015

Implantable drug delivery systems can provide long-term reliability, controllability, and biocompatibility, and have been used in many applications, including cancer pain and non-malignant pain treatment. However, many of the available systems are limited to zero-order, inconsistent, or single burst event drug release. To address these limitations, we demonstrate prototypes of a remotely operated drug delivery device that offers controllability of drug release profiles, using osmotic pumping as a pressure source and magnetically triggered membranes as switchable on-demand valves. The membranes are made of either ethyl cellulose, or the proposed stronger cellulose acetate polymer, mixed with thermosensitive poly(N-isopropylacrylamide) hydrogel and superparamagnetic iron oxide particles. The prototype devices' drug diffusion rates are on the order of 0.5–2 μg/h for higher release rate designs, and 12–40 ng/h for lower release rates, with maximum release ratios of 4.2 and 3.2, respectively. The devices exhibit increased drug delivery rates with higher osmotic pumping rates or with magnetically increased membrane porosity. Furthermore, by vapor deposition of a cyanoacrylate layer, a drastic reduction of the drug delivery rate from micrograms down to tens of nanograms per hour is achieved. By utilizing magnetic membranes as the valve-control mechanism, triggered remotely by means of induction heating, the demonstrated drug delivery devices benefit from having the power source external to the system, eliminating the need for a battery. These designs multiply the potential approaches towards increasing the on-demand controllability and customizability of drug delivery profiles in the expanding field of implantable drug delivery systems, with the future possibility of remotely controlling the pressure source.
Power combiner with high power capacity and high combination efficiency for two phase-locked relativistic backward wave oscillators
Authors: Xiao Renzhen , Deng Yuqun , Wang Yue , Song Zhimin , Li Jiawei , Sun Jun , Chen Changhua
Published: September 2015

To realize power combination of two phase-locked relativistic backward wave oscillators (RBWOs), a compact power combiner is designed and investigated by 3-D particle-in-cell (PIC) simulation and experiment. The power combiner consists of two TM01-TE11 serpentine mode converters with a common output. When the two incident ports are fed with TM01 modes with a relative phase of 180° and power of 2.5 GW at each port, the conversion efficiency from the incident TM01 modes to the combined TE11 mode is 95.2% at 9.3 GHz, and the maximum electric field in the combiner is 714 kV/cm. The PIC simulation shows that the output power from the common port is 4.2 GW when the power combiner is connected to the two RBWOs with input signals, both producing 2.2 GW microwave, corresponding to a combination efficiency of 95.4%. In the high power microwave test, a method is proposed to obtain the combination efficiency without breaking the vacuum, which is 94.1% when the two phase-locked RBWOs output 1.8 GW and 2.2 GW. The power capacity of multi-gigawatts has been demonstrated.
Electric-field induced nonlinear ferromagnetic resonance in a CoFeB/MgO magnetic tunnel junction
Authors: Hirayama E. , Kanai S. , Ohe J. , Sato H. , Matsukura F. , Ohno H.
Published: September 2015

We investigate the rf power dependence of homodyne-detected ferromagnetic resonance (FMR) spectra of a nanoscale CoFeB/MgO magnetic tunnel junction, in which the FMR is induced by the electric-field modulation of the magnetic anisotropy. The increase of the rf power changes the spectral lineshape and decreases characteristic frequency, at which drastic change in spectrum is observed. The behavior is consistent with nonlinear magnetization precession with a large precessional angle at high powers. From the rf power dependence of FMR spectra, we determine electric-field modulation ratio of magnetic anisotropy energy density to be 78 fJ/Vm, which is in agreement with the reported values.
Fabrication of Pt nanowires with a diffraction-unlimited feature size by high-threshold lithography
Authors: Li Li , Wang Zuobin , Li Wenjun , Peng Kuiqing , Zhang Ziang , Yu Miao , Song Zhengxun , Weng Zhankun , Wang Dapeng , Zhao Le
Published: September 2015

Although the nanoscale world can already be observed at a diffraction-unlimited resolution using far-field optical microscopy, to make the step from microscopy to lithography still requires a suitable photoresist material system. In this letter, we consider the threshold to be a region with a width characterized by the extreme feature size obtained using a Gaussian beam spot. By narrowing such a region through improvement of the threshold sensitization to intensity in a high-threshold material system, the minimal feature size becomes smaller. By using platinum as the negative photoresist, we demonstrate that high-threshold lithography can be used to fabricate nanowire arrays with a scalable resolution along the axial direction of the linewidth from the micro- to the nanoscale using a nanosecond-pulsed laser source with a wavelength λ0 = 1064 nm. The minimal feature size is only several nanometers (sub λ0/100). Compared with conventional polymer resist lithography, the advantages of high-threshold lithography are sharper pinpoints of laser intensity triggering the threshold response and also higher robustness allowing for large area exposure by a less-expensive nanosecond-pulsed laser.
Unexpected magnetic behavior in amorphous Co90Sc10 alloy
Authors: Ghafari M. , Sakurai Y. , Peng G. , Fang Y. N. , Feng T. , Hahn H. , Gleiter H. , Itou M. , Kamali S.
Published: September 2015

An amorphous alloy Co90Sc10 has been prepared by rapid quenching from the melt. The results of magnetization measurements show that this alloy has the highest Curie temperature reported for any amorphous transition metal based alloys. Furthermore, for a Co based amorphous alloy, the magnetic moment is remarkably high. Moreover, the alloy exhibits soft magnetic properties. Based on the findings, amorphous Co90Sc10 appears to be an attractive candidate for applications as a soft magnetic material. The temperature dependence of the reduced magnetization can be described by the Bloch power law. The results show that the B coefficient of the amorphous Co90Sc10 alloy, which is a measure of the rigidity of spin waves, exhibits the lowest value observed until now for any amorphous alloy and is comparable to crystalline alloys. It is found that the Sc atoms in the Co90Sc10 alloy lead to an increase of the itinerant spin moment of Co atoms, and, in contrast to this behaviour, to a decrease of the local 3d-electrons of Co.
Efficient frequency conversion by stimulated Raman scattering in a sodium nitrate aqueous solution
Authors: Ganot Yuval , Bar Ilana
Published: September 2015

Frequency conversion of laser beams, based on stimulated Raman scattering (SRS) is an appealing technique for generating radiation at new wavelengths. Here, we investigated experimentally the SRS due to a single pass of a collimated frequency-doubled Nd:YAG laser beam (532 nm) through a saturated aqueous solution of sodium nitrate (NaNO3), filling a 50 cm long cell. These experiments resulted in simultaneous generation of 1st (564 nm) and 2nd (599 nm) Stokes beams, corresponding to the symmetric stretching mode of the nitrate ion, ν1(NO3−), with 40 and 12 mJ/pulse maximal converted energies, equivalent to 12% and 4% efficiencies, respectively, for a 340 mJ/pulse pump energy. The results indicate that the pump and SRS beams were thermally defocused and that four-wave mixing was responsible for the second order Stokes process onset.
Three-terminal graphene single-electron transistor fabricated using feedback-controlled electroburning
Authors: Puczkarski Paweł , Gehring Pascal , Lau Chit S. , Liu Junjie , Ardavan Arzhang , Warner Jamie H. , Briggs G. Andrew D. , Mol Jan A.
Published: September 2015

We report room-temperature Coulomb blockade in a single layer graphene three-terminal single-electron transistor fabricated using feedback-controlled electroburning. The small separation between the side gate electrode and the graphene quantum dot results in a gate coupling up to 3 times larger compared to the value found for the back gate electrode. This allows for an effective tuning between the conductive and Coulomb blocked state using a small side gate voltage of about 1 V. The technique can potentially be used in the future to fabricate all-graphene based room temperature single-electron transistors or three terminal single molecule transistors with enhanced gate coupling.
Molecular versus crystallite PCBM diffusion in P3HT:PCBM blends
Authors: Berriman Garth A. , Holdsworth John L. , Zhou Xiaojing , Belcher Warwick J. , Dastoor Paul C.
Published: September 2015

The diffusion of PCBM in P3HT:PCBM blend films has been investigated using multi-wavelength scanning absorption microscopy (MWSAM). By studying the depletion of PCBM in the vicinity of the phase segregated PCBM-rich regions that form upon thermal annealing, we are able to measure the diffusion constant and activation energy for PCBM diffusion in P3HT:PCBM blend films. The measured kinetic parameters are consistent with the diffusion of nanoscale PCBM crystallites rather than molecular PCBM. We show that the presence of two distinct diffusion processes in these blend materials provides an explanation for the large differences that have been reported for PCBM diffusion in P3HT:PCBM blends. This insight allows us to develop a unified model for PCBM mass transport in these materials.
Administration of thimerosal-containing vaccines to infant rhesus macaques does not result in autism-like behavior or neuropathology
Authors: Gadad Bharathi S. , Li Wenhao , Yazdani Umar , Grady Stephen , Johnson Trevor , Hammond Jacob , Gunn Howard , Curtis Britni , English Chris , Yutuc Vernon , Ferrier Clayton , Sackett Gene P. , Marti C. Nathan , Young Keith , Hewitson Laura , German Dwight C.
Published: September 2015

Significance

Autism is a childhood neurodevelopmental disorder affecting approximately 1 in 70 children in the United States. Some parents believe that thimerosal-containing vaccines and/or the measles, mumps, rubella (MMR) vaccine are involved in the etiology of autism. Here we gave nonhuman primate infants similar vaccines given to human infants to determine whether the animals exhibited behavioral and/or neuropathological changes characteristic of autism. No behavioral changes were observed in the vaccinated animals, nor were there neuropathological changes in the cerebellum, hippocampus, or amygdala. This study does not support the hypothesis that thimerosal-containing vaccines and/or the MMR vaccine play a role in the etiology of autism.
The TWD40-2 protein and the AP2 complex cooperate in the clathrin-mediated endocytosis of cellulose synthase to regulate cellulose biosynthesis
Authors: Bashline Logan , Li Shundai , Zhu Xiaoyu , Gu Ying
Published: September 2015

Significance

Our study advances the understanding of how plants make cellulose, a critical constituent of the plant cell wall and the most abundant organic polymer in the terrestrial biosphere. Cellulose is synthesized at the plasma membrane by cellulose synthase (CESA) complexes. Here we highlight the importance of regulated CESA endocytosis in cellulose biosynthesis in
Arabidopsis
. Furthermore, we show that the TWD40-2 protein, a putative member of the TPLATE complex, functions in clathrin-mediated endocytosis (CME) in ways that are both distinct from and cooperative with the functionally conserved CME adaptor protein 2 (AP2) complex. Because the TPLATE complex of plants is not conserved in animals, our characterization of TWD40-2 offers the opportunity to provide insight into the evolution of eukaryotic trafficking machinery.
Noninvasive brain cancer imaging with a bispecific antibody fragment, generated via click chemistry
Authors: Luo Haiming , Hernandez Reinier , Hong Hao , Graves Stephen A. , Yang Yunan , England Christopher G. , Theuer Charles P. , Nickles Robert J. , Cai Weibo
Published: September 2015

Significance

Given the success of combination therapies for the treatment of cancer, the use of bispecific antibodies targeting multiple cancerous molecular pathways is an attractive strategy to enhance the efficacy of current therapeutic paradigms. However, parallel development of companion diagnostic tools is essential for patient identification, stratification, and the early assessment of treatment efficacies. Herein, we describe the generation of a bispecific construct for noninvasive PET imaging of glioblastoma via bioorthogonal click chemistry. The excellent tumor-homing properties displayed by our bispecific probe, which features two antibody fragments simultaneously targeting epidermal growth factor receptor and CD105, demonstrated that our approach is a simple and effective method to generate multispecific targeting agents for noninvasive molecular imaging.
New roles for DNA cytosine modification, eRNA, anchors, and superanchors in developing B cell progenitors
Authors: Benner Christopher , Isoda Takeshi , Murre Cornelis
Published: September 2015

Significance

B cells are destined to produce a wide spectrum of antibodies or immunoglobulins in response to the invading pathogens. Here, we found that the onset of B-cell development was accompanied by large-scale changes in DNA cytosine modifications associated with DNA elements that control gene expression and the folding patterns of genomes. We identify novel DNA elements that function as superanchors and/or superinsulators. A prominent super-anchor is located in the immunoglobulin heavy chain locus where it acts to facilitate the interactions among variable, diversity, and joining DNA segments. We propose that changes in DNA cytosine modifications at regulatory DNA elements orchestrate a B cell-specific transcription signature and genome structure to enable the production of a diverse antibody repertoire.
Experimental test of the viscous anisotropy hypothesis for partially molten rocks
Authors: Qi Chao , Kohlstedt David L. , Katz Richard F. , Takei Yasuko
Published: September 2015

Significance

Partially molten regions of Earth link mantle convection with surface volcanism. We present laboratory experiments and theory that are at the heart of understanding the connection between these interior and surface processes. The theory proposes that the presence of melt fundamentally changes the style of deformation, making it anisotropic with leading-order, testable consequences. The laboratory results are in agreement with theoretical predictions. These results are novel at a foundational level and profoundly surprising. Together they make the case that the creep rheology of partially molten rocks is more than the sum of its parts. Moreover, this article sets forth a framework that will guide a broad swath of future research in rock mechanics and mantle flow.
No barrier to emergence of bathyal king crabs on the Antarctic shelf
Authors: Aronson Richard B. , Smith Kathryn E. , Vos Stephanie C. , McClintock James B. , Amsler Margaret O. , Moksnes Per-Olav , Ellis Daniel S. , Kaeli Jeffrey , Singh Hanumant , Bailey John W. , Schiferl Jessica C. , van Woesik Robert , Martin Michael A. , Steffel Brittan V. , Deal Michelle E. , Lazarus Steven M. , Havenhand Jonathan N. , Swalethorp Rasmus , Kjellerup Sanne , Thatje Sven
Published: September 2015

Significance

For tens of millions of years, cold conditions have excluded shell-crushing fish and crustaceans from the continental shelf surrounding Antarctica. Rapid warming is now allowing predatory crustaceans to return. Our study of the continental slope off the western Antarctic Peninsula showed that abundant, predatory king crabs comprise a reproductively viable population at 841- to 2,266-m depth. Depth profiles of temperature, salinity, habitat structure, food availability, and predators indicate that there are no barriers to prevent king crabs from moving upward onto the outer shelf at 400–550 m. A cold-water barrier above 200 m could be breached within the next few decades. Emergence of king crabs on the shelf could have catastrophic consequences for the unique seafloor communities of Antarctica.
Dark matter universe
Authors: Bahcall Neta A.
Published: September 2015

Most of the mass in the universe is in the form of dark matter—a new type of nonbaryonic particle not yet detected in the laboratory or in other detection experiments. The evidence for the existence of dark matter through its gravitational impact is clear in astronomical observations—from the early observations of the large motions of galaxies in clusters and the motions of stars and gas in galaxies, to observations of the large-scale structure in the universe, gravitational lensing, and the cosmic microwave background. The extensive data consistently show the dominance of dark matter and quantify its amount and distribution, assuming general relativity is valid. The data inform us that the dark matter is nonbaryonic, is “cold” (i.e., moves nonrelativistically in the early universe), and interacts only weakly with matter other than by gravity. The current Lambda cold dark matter cosmology—a simple (but strange) flat cold dark matter model dominated by a cosmological constant Lambda, with only six basic parameters (including the density of matter and of baryons, the initial mass fluctuations amplitude and its scale dependence, and the age of the universe and of the first stars)—fits remarkably well all the accumulated data. However, what is the dark matter? This is one of the most fundamental open questions in cosmology and particle physics. Its existence requires an extension of our current understanding of particle physics or otherwise point to a modification of gravity on cosmological scales. The exploration and ultimate detection of dark matter are led by experiments for direct and indirect detection of this yet mysterious particle.
Italian anti-Fascism in London, 1922–1934
Authors: Rampello Stefania
Published: September 2015

Between the end of the Great War and the start of the Second World War, various Italians living in London, who for the most part had migrated there around the start of the twentieth century, started their own particular determined opposition to Fascism. Their initial aim was to counter Fascist monopolisation of London's Italian community, contesting control of the community's main associations, institutes and cultural bodies by the Fascio, which had been established in London in 1921. Subsequently, these anti-Fascists also sought contacts outside London's Little Italy, on the one hand with British political bodies and the British press, and on the other with anti-Fascists in other countries. While strong links were formed with the latter, British society showed only a muted interest. This is in part explained by the positive response to the Fascist experience by the Conservative press and various eminent British politicians, at least until the mid-1930s.
Nonrenewable resources, institutions and foreign direct investments in developing countries
Authors: Ibrahim-Shwilima Amos James
Published: September 2015

In this paper we examine the impact of institutions on attracting foreign direct investment (FDI) in the resource-rich developing countries and compare to the non-resource rich countries. We followed the empirical approach on data from 104 countries covering the period 1995–2010. In this study the institutions are measured by using the indexes of democracy and the rule of law. When these indexes are tested simultaneously we find that the improvement in the quality of democracy promotes FDI to both resource-rich and non-resource rich countries. However, improvement of the rule of law promotes FDI only if the share of nonrenewable resources in total exports is below a certain critical value. Also our findings suggest that resource-rich countries keep attracting FDI regardless of the quality of their institutions. This may explain why some resource-rich countries stay non-democratic and delay in improving the quality in the rule of law.