bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, in vitro evaluation and DNA interaction studies of N-allyl naphthalimide analogues as anticancer agents
Authors: Verma Meenakshi , Luxami Vijay , Paul Kamaldeep
Published: May 2015

A novel series of 2-allyl-6-substituted-benzo[de]isquinoline-1,3-diones has been synthesized and evaluated for their in vitro antitumor activities and DNA intercalation.
Identifying MurI uncompetitive inhibitors by correlating decomposed binding energies with bioactivity
Authors: Le Xiu , Gu Qiong , Xu Jun
Published: April 2015

MurI uncompetitive inhibitors can be virtually identified by a new method that correlates decomposed binding free energies with the bioactivity.
Effect of heat treatment time on cycle performance of LiMn2O4with “Nano Inclusion” for lithium ion batteries
Authors: Esaki Shogo , Nishijima Motoaki , Takai Shigeomi , Yao Takeshi
Published: May 2015

The cycle performance of LiMn2O4with “Nano Inclusions” is higher than that of LiMn2O4without “Nano Inclusions” and the discharge capacity of LiMn2O4with “Nano Inclusions” heat-treated for 4 h surpassed that of LiMn2O4without it at over 31 cycles.
High-performance nickel manganese ferrite/oxidized graphene composites as flexible and binder-free anodes for Li-ion batteries
Authors: Zhang Zailei , Tan Qiangqiang , Zhong Ziyi , Su Fabing
Published: April 2015

The obtained binder-free and flexible free-standing Ni0.5Mn0.5Fe2O4/oxidized graphene (NMFO/OGP) and NMFO/OGP coated on polypropylene microporous film exhibited good electrochemical performance.
An effective template-free synthesis strategy for hierarchical titanium oxide hybrids: tailoring the solvent environment
Authors: Wang Sharon Y. , Soe Myo Tint , Guo Kevin T. , Zhang Xiao Li , Guo Zheng Xiao
Published: May 2015

Tailoring solvent composition and concentration in solvothermal treatment enables effective control of morphological evolution of hierarchical titanium-oxide hybrid materials.
Tribological behavior of TiAl matrix self-lubricating composites reinforced by multilayer graphene
Authors: Yang Kang , Shi Xiaoliang , Zhai Wenzheng , Chen Long , Zhang Ao , Zhang Qiaoxin
Published: April 2015

Anti-friction film with friction-reduction and anti-wear properties is formed under elastic deformation at the von Mises stress of 917 MPa (at 12 N).
Effect of intrinsic and extrinsic factors on the stability of the α-gel phase of a glyceryl monostearate–water system
Authors: Wang Fan C. , Marangoni Alejandro G.
Published: May 2015

The α-gel phase of glycerlyl monostearate was stabilized by using specific co-surfactants, by setting slowly from the Lα phase and by avoiding shear.
Mapping students' conceptual modes when thinking about chemical reactions used to make a desired product
Authors: Weinrich M. L. , Talanquer V.
Published: April 2015

The central goal of this qualitative research study was to uncover major implicit assumptions that students with different levels of training in the discipline apply when thinking and making decisions about chemical reactions used to make a desired product. In particular, we elicited different ways of conceptualizing why chemical reactions happen (chemical causality), how these processes occur (chemical mechanism), and how they can be controlled (chemical control). In each of these areas we characterized conceptual modes with different explanatory power and explored how they were applied by participants when facing different types of questions. Our findings suggest potential paths in the development of understanding about chemical reactions in the context of making specific substances. Our study also highlights the benefits of analyzing students' understanding not only by focusing on implicit cognitive elements, but by using disciplinary crosscutting concepts as lenses of analysis.
Solution structural characterization of an array of nanoscale aqueous inorganic Ga13−xInx (0 ≤ x ≤ 6) clusters by 1H-NMR and QM computations
Authors: Oliveri Anna F. , Wills Lindsay A. , Hazlett Caitlyn R. , Carnes Matthew E. , Chang I-Ya , Ha-Yeon Cheong Paul , Johnson Darren W.
Published: April 2015

Complete structural determination by 1H NMR spectroscopy and QM computations reveals a series of heterometallic Ga13−xInx(μ3-OH)6(μ2-OH)18(H2O)24](NO3)15 clusters persist in solution and can exist as an isomeric mixture.
Steric shielding vs. σ–π orbital interactions in triplet–triplet energy transfer
Authors: Andreu Inmaculada , Morera Isabel , Palumbo Fabrizio , Sastre German , Bosca Francisco , Miranda Miguel A.
Published: May 2015

Fine tuning of the benzoylthiophene triplet level through σ–π orbital interactions modifies the energy transfer rate constants to appropriate acceptors.
Revealing the thermodynamic driving force for ligand-based reductions in quinoids; conceptual rules for designing redox active and non-innocent ligands
Authors: Skara G. , Pinter B. , Geerlings P. , De Proft F.
Published: May 2015

The easy reduction of quinoid ligands is driven thermodynamically by superior M–L electrostatics and σ-bonding in the reduced form.
Statistics of non-affine defect precursors: tailoring defect densities in colloidal crystals using external fields
Authors: Ganguly Saswati , Sengupta Surajit , Sollich Peter
Published: May 2015

Coarse-graining atomic displacements in a solid produces local affine strains and “non-affine” fluctuations. Here we show how a subset of these thermally excited non-affine fluctuations act as defect precursors and suggest how defect probabilities may be altered by an experimentally realisable “external field” conjugate to the global non-affinity parameter..
From coffee rings to coffee eyes
Authors: Li Yanshen , Lv Cunjing , Li Zhaohan , Quéré David , Zheng Quanshui
Published: May 2015

The morphology of the deposit after evaporation of a suspension changes from a ring shape to an eye shape, that is, a combination of the central stain and the thinner ring, upon increasing the substrate temperature.
Pristine-state structure of lithium-ion-battery cathode material Li1.2Mn0.4Co0.4O2 derived from NMR bond pathway analysis
Authors: Iddir Hakim , Key Baris , Dogan Fulya , Russell John T. , Long Brandon R. , Bareño Javier , Croy Jason R. , Benedek Roy
Published: May 2015

Layered lithium ion battery cathode materials have been extensively investigated, of which layered–layered composites xLi2MnO3·(1 − x)LiMO2 (M = Mn, Co, Ni) are of particular interest, owing to their high energy density.
Effects of structural disorder and nitrogen content on the oxygen reduction activity of polyvinylpyrrolidone-derived multi-doped carbon
Authors: Sharma Raghunandan , Kar Kamal K.
Published: April 2015

The effects of pyrolysis temperature and acid-treatment on the oxygen reduction catalytic activity of N-, O- and Co-doped carbons have been studied.
A new Pb(iv)-based photocathode material Sr2PbO4with good light harvesting ability
Authors: Zhao Dan , Han Jing-Feng , Cui Jun-Yan , Zong Xu , Li Can
Published: April 2015

This work reported a new p-type photocathode material Sr2PbO4with visible light harvesting ability up to 710 nm.
Upconversion NaLuF4 fluorescent nanoprobes for jellyfish cell imaging and irritation assessment of organic dyes
Authors: Chen Zenghui , Wu Xiaofeng , Hu Shigang , Hu Pan , Yan Huanyuan , Tang Zhijun , Liu Yunxin
Published: May 2015

Upconversion NaLuF4 nanoprobes with intense visible fluorescence and good biocompatibility have been successfully constructed for assessing the irritation of trace organic molecules in jellyfish cells based on the LRET process.
Structure and luminescence properties of a novel yellow super long-lasting phosphate phosphor Ca6BaP4O17:Eu2+,Ho3+
Authors: Guo Haijie , Chen Wenbo , Zeng Wei , Li Gen , Wang Yuhua , Li Yanyan , Li Yang , Ding Xin
Published: May 2015

The brand new LLP material Ca6BaP4O17:Eu2+,Ho3+exhibits about 0.13 cd m−2initial LLP intensity and a 47 h afterglow.
Efficient intra‐mode decision algorithm skipping unnecessary depth‐modelling modes in 3D‐HEVC
Authors: Park Chun‐Su
Published: May 2015

The three‐dimensional (3D) extension of the high‐efficiency video coding (3D‐HEVC) standard adopts new depth‐modelling modes (DMMs) to provide an alternative prediction scheme for depth‐map intra‐coding. In 3D‐HEVC, although edges in depth maps can be accurately estimated by utilising the DMMs, testing the DMMs in the mode decision introduces a huge computational load to the encoder. A fast mode decision algorithm is proposed that can significantly reduce the computational overhead incurred by the DMMs. Experimental results indicate that the proposed algorithm reduces the encoding complexity by 33.89% on average without any penalty in coding efficiency.
Blue enhanced vertically stacked quad junction photodetector with opto window
Authors: Schidl S. , Enne R. , Zimmermann H.
Published: May 2015

A vertically stacked quad junction photodetector (PD) with an enhanced spectral responsivity for blue light is presented. This PD is implemented in a 0.35 µm high voltage complementary metal‐oxide semiconductor (CMOS) technology. In addition, an optical window, an antireflection coating and a modified p+ doping are used to attain the enhancement for blue light. The proposed PD is compared against other state of the art implementations and characterised for its spectral response.
237 Gbit/s unrolled hardware polar decoder
Authors: Giard P. , Sarkis G. , Thibeault C. , Gross W.J.
Published: May 2015

A new architecture for a polar decoder using a reduced complexity successive‐cancellation (SC) decoding algorithm is presented. This novel fully unrolled, deeply pipelined architecture is capable of achieving a coded throughput of over 237 Gbit/s for a (1024, 512) polar code implemented using a field‐programmable gate array. This decoder is two orders of magnitude faster than state‐of‐the‐art polar decoders.
Classification performance using 'RF‐DNA' fingerprinting of ultra‐wideband noise waveforms
Authors: Lukacs M. , Collins P. , Temple M.
Published: May 2015

Device classification is important in many applications such as industrial quality control, through‐wall imaging and network security. A novel approach has been proposed to use a digital noise radar (DNR) to actively interrogate microwave devices and classify defective units using ‘radio frequency distinct native attribute (RF‐DNA)’ fingerprinting and various classifier algorithms. RF‐DNA has previously demonstrated ‘serial number’ discrimination of numerous passive radio frequency signals, achieving classification accuracies above 80% using multiple discriminant analysis/maximum likelihood (MDA/ML) and generalised relevance learning vector quantisation‐improved (GRLVQI) classifiers. It has also demonstrated above 80% classification of limited active interrogation responses with a DNR signal using these classifiers. The performance capabilities of the two different classifiers, MDA/ML and GRLVQI, on RF‐DNA fingerprints produced from the ultra‐wideband noise radar correlation response is expanded.
Compact CPW‐fed triple‐band antenna for diversity applications
Authors: Wu Rui‐Zhi , Wang Peng , Zheng Qiang , Li Rui‐Peng
Published: May 2015

A compact coplanar waveguide (CPW)‐fed triple‐band monopole antenna with high‐band isolation for various wireless applications is presented. The proposed antenna is composed of a CPW‐fed structure and a hexagon‐shaped patch on which a hexagon‐shaped slot is etched for covering the wireless local area network (WLAN) band (2.4/5.2/5.8 GHz), and occupies a very compact size of 26 × 25 mm2. By introducing a half‐hexagon‐shaped stub, additional bands can be realised covering the worldwide interoperability for microwave access (WIMAX) band (2.5/3.5/5.5 GHz). The proposed antenna has been fabricated and measured; results show a higher isolation between adjacent bands, good radiation pattern characteristics and stable gains in the operating bands. The simple feeding structure, compact size and uniplanar design make it easy to be integrated within portable devices for wireless communication.
Pose‐invariant gender classification based on 3D face reconstruction and synthesis from single 2D image
Authors: Moeini A. , Moeini H.
Published: May 2015

A novel method is proposed for pose‐invariant gender classification based on three‐dimensional (3D) face reconstruction from only 2D frontal images. A 3D face model is reconstructed from only a single 2D frontal image. Then, for each two‐class of gender in the database, a feature library matrix (FLM) is created from yaw face poses by rotating the 3D reconstructed models and extracting features in the rotated face. Each FLM is subsequently rendered based on the yaw angles of face poses. Then, an array of the FLM is selected based on the estimated yaw angles for each class of gender. Finally, the selected arrays from FLMs are compared with target image features by support vector machine classification. Promising results are acquired to handle pose in gender classification on the available compared with the state‐of‐the‐art methods.
Design of Ku‐band transformer‐based cross‐coupled complementary LC‐VCO
Authors: Jalalifar M. , Byun G.‐S.
Published: May 2015

A transformer‐based cross‐coupled complementary LC voltage‐controlled oscillator (VCO) is investigated which is capable of operating at the Ku‐band frequency range with low power consumption. The VCO simultaneously achieves low phase noise and low power consumption. The VCO demonstrates a measured tuning range of 12.1–13.1 GHz and a phase noise of −116.4 dBc/Hz at 1 MHz at a centre frequency of 12.4 GHz. The VCO consumes 0.96 mW from a 0.45 V supply voltage with a figure of merit of 198.4. It is implemented in a standard 0.13 µm CMOS process with an area of 0.23 mm2.
Access control based on gait analysis and face recognition
Authors: Derbel A. , Vivet D. , Emile B.
Published: May 2015

According to a new market research report, electronic access control system is expected to be worth $16.3 billion by 2017. Vision‐based biometric authentication systems have received much attention with increasing demands for long distance surveillance applications and access control to the security area. Such visual application is mainly focused on face recognition. Nevertheless, small size or poor quality images with varying poses, illumination, expressions, glasses or hats and so on can perturb the recognition. To deal with such problems, the fusing of both face recognition and gait analysis is proposed. Gait has recently become one of the most emerging biometrics for non‐intrusive person identification. A system is proposed in which information provided by face recognition and gait analysis is fused to identify people. Such a system has direct industrial applications since it is a non‐intrusive security system that is reliable, easily deployable and just needs an inexpensive camera.
Impacts of renewables generation and demand patterns on net transfer capacity: implications for effectiveness of market splitting in Germany
Authors: Bucksteeg Michael , Trepper Katrin , Weber Christoph
Published: May 2015

For the further development of an integrated European electricity market, congestion management mechanisms are one of the major market design issues. Against the background of increasing generation from renewables and resulting congestions, an efficient management of network congestions is gaining importance especially in Germany. Introducing nodal pricing as the first best mechanism is not considered to be realistic for Germany in the nearby future. Yet the splitting of the German electricity market into several market zones will also improve congestion management. A key issue in the so‐called market splitting is the determination of the net transfer capacity (NTC) between the market zones as it determines the effectiveness of market splitting as congestion management mechanism. The authors therefore propose an integrated approach to incorporate the effects of renewables feed‐in, load patterns and cross‐border flows on NTCs. On the basis of results of a European power market model they specify typical hours using a clustering approach. Subsequently, a DC security constrained optimal power flow model is used to calculate situation‐dependent NTCs. They conclude that the obtained NTCs strongly depend on renewables feed‐in and that this effect has to be considered when modelling alternative congestion management mechanisms such as market splitting.
Wide‐area damping control for inter‐area oscillations using inverse filtering technique
Authors: Goldoost‐Soloot Reza , Mishra Yateendra , Ledwich Gerard
Published: May 2015

In this study, a non‐linear excitation controller using inverse filtering is proposed to damp inter‐area oscillations. The proposed controller is based on determining generator flux value for the next sampling time which is obtained by maximising reduction rate of kinetic energy of the system after the fault. The desired flux for the next time interval is obtained using wide‐area measurements and the equivalent area rotor angles and velocities are predicted using a non‐linear Kalman filter. A supplementary control input for the excitation system, using inverse filtering approach, to track the desired flux is implemented. The inverse filtering approach ensures that the non‐linearity introduced because of saturation is well compensated. The efficacy of the proposed controller with and without communication time delay is evaluated on different IEEE benchmark systems including Kundur's two area, Western System Coordinating Council three‐area and 16‐machine, 68‐bus test systems.
Perspective: Stimulated Raman adiabatic passage: The status after 25 years
Authors: Bergmann Klaas , Vitanov Nikolay V. , Shore Bruce W.
Published: May 2015

The first presentation of the STIRAP (stimulated Raman adiabatic passage) technique with proper theoretical foundation and convincing experimental data appeared 25 years ago, in the May 1st, 1990 issue of The Journal of Chemical Physics. By now, the STIRAP concept has been successfully applied in many different fields of physics, chemistry, and beyond. In this article, we comment briefly on the initial motivation of the work, namely, the study of reaction dynamics of vibrationally excited small molecules, and how this initial idea led to the documented success. We proceed by providing a brief discussion of the physics of STIRAP and how the method was developed over the years, before discussing a few examples from the amazingly wide range of applications which STIRAP now enjoys, with the aim to stimulate further use of the concept. Finally, we mention some promising future directions.
Anisotropy of resistivity in Bi93.99Mn6Fe0.01
Authors: Svetlov V. N. , Terekhov A. V. , Stepanov V. B. , Solovjov A. L. , Khristenko E. V. , Ivasishin O. M. , Shevchenko A. D. , Kovalyuk Z. D.
Published: May 2015

For the first time the longitudinal and transverse magneto-resistive effect in textured polycrystalline Bi93.99Mn6Fe0.01 was studied. The ρ(T) dependences were measured in a wide temperature range from 4.2 K up to 300 K, both with no magnetic field applied and in a dc magnetic field of 6 T. Positive magnetoresistance as well as crystallographic and magnetic anisotropies of resistivity were revealed.
2D heterodyne-detected sum frequency generation study on the ultrafast vibrational dynamics of H2O and HOD water at charged interfaces
Authors: Inoue Ken-ichi , Nihonyanagi Satoshi , Singh Prashant C. , Yamaguchi Shoichi , Tahara Tahei
Published: April 2015

Two-dimensional heterodyne-detected vibrational sum-frequency generation (2D HD-VSFG) spectroscopy is applied to study the ultrafast vibrational dynamics of water at positively charged aqueous interfaces, and 2D HD-VSFG spectra of cetyltrimethylammonium bromide (CTAB)/water interfaces in the whole hydrogen-bonded OH stretch region (3000 cm−1 ≤ ωpump ≤ 3600 cm−1) are measured. 2D HD-VSFG spectrum of the CTAB/isotopically diluted water (HOD-D2O) interface exhibits a diagonally elongated bleaching lobe immediately after excitation, which becomes round with a time constant of ∼0.3 ps due to spectral diffusion. In contrast, 2D HD-VSFG spectrum of the CTAB/H2O interface at 0.0 ps clearly shows two diagonal peaks and their cross peaks in the bleaching region, corresponding to the double peaks observed at 3230 cm−1 and 3420 cm−1 in the steady-state HD-VSFG spectrum. Horizontal slices of the 2D spectrum show that the relative intensity of the two peaks of the bleaching at the CTAB/H2O interface gradually change with the change of the pump frequency. We simulate the pump-frequency dependence of the bleaching feature using a model that takes account of the Fermi resonance and inhomogeneity of the OH stretch vibration, and the simulated spectra reproduce the essential features of the 2D HD-VSFG spectra of the CTAB/H2O interface. The present study demonstrates that heterodyne detection of the time-resolved VSFG is critically important for studying the ultrafast dynamics of water interfaces and for unveiling the underlying mechanism.
Comment on “The ion kinetic D'Angelo mode” [Phys. Plasmas 18, 102105 (2011)]
Authors: Aman-ur-Rehman  , Shan Shaukat Ali , Saleem Hamid
Published: April 2015

It is pointed out that the analysis of the shear flow and its different limiting cases presented in the paper, Phys. Plasmas 18, 102105 (2011), using kinetic approach is misleading.
Response to “Comment on ‘The ion-kinetic D'Angelo mode’” [Phys. Plasmas 22, 044703 (2015)]
Authors: Chibisov D. V. , Mikhailenko V. S.
Published: April 2015

A response to “Comment on ‘The ion-kinetic D'Angelo mode’” by Aman-ur-Rehman, Shaukat Ali Shan, and Hamid Saleem is given. We find that all Comments are grounded on the misinterpretations of the results of our paper “The ion-kinetic D'Angelo mode” and are erroneous.
Imaging polychromator for density measurements of polystyrene pellet cloud on the Large Helical Device
Authors: Sharov I. A. , Sergeev V. Yu. , Miroshnikov I. V. , Tamura N. , Kuteev B. V. , Sudo S.
Published: April 2015

Experimental data on spatial distributions of a pellet cloud electron density are necessary for the development of many applications of pellet injection, namely, plasma fuelling, discharge control, and plasma diagnostics. An improved approach of electron density measurements inside the cloud of a polystyrene pellet ablating in hot plasma of the large helical device is described. Density values of (1-30) × 1016 cm−3 depending on the background plasma parameters and distance from the solid pellet were measured.
Magnetotransport in p-type Ge quantum well narrow wire arrays
Authors: Newton P. J. , Llandro J. , Mansell R. , Holmes S. N. , Morrison C. , Foronda J. , Myronov M. , Leadley D. R. , Barnes C. H. W.
Published: April 2015

We report magnetotransport measurements of a SiGe heterostructure containing a 20 nm p-Ge quantum well with a mobility of 800 000 cm2 V−1 s−1. By dry etching arrays of wires with widths between 1.0 μm and 3.0 μm, we were able to measure the lateral depletion thickness, built-in potential, and the phase coherence length of the quantum well. Fourier analysis does not show any Rashba related spin-splitting despite clearly defined Shubnikov-de Haas oscillations being observed up to a filling factor of ν = 22. Exchange-enhanced spin-splitting is observed for filling factors below ν = 9. An analysis of boundary scattering effects indicates lateral depletion of the hole gas by 0.5 ± 0.1 μm from the etched germanium surface. The built-in potential is found to be 0.25 ± 0.04 V, presenting an energy barrier for lateral transport greater than the hole confinement energy. A large phase coherence length of 3.5 ± 0.5 μm is obtained in these wires at 1.7 K.
Optimization of a thermomagnetic motor
Authors: Trapanese Marco , Cipriani Giovanni , Di Dio Vincenzo , Franzitta Vincenzo , Viola Alessia
Published: April 2015

In this paper, an approach towards the optimization of the Curie motor is presented. The approach is based on a thermal-magnetic coupled dynamic model of the motor, which is obtained by assuming the use of a ferromagnetic material working at temperatures near the Curie point. An analytical expression of the generated torque, which links this quantity to the magnetic, thermal, and geometrical parameters of the generated torque, is given. The expressions of speed and torque are derived and related to the thermal properties of the machine and are used as optimization indexes in an optimization procedure. The aim of the optimization process is to obtain a machine able to rotate constantly at the maximum achievable power. A design of a machine, based on this theory, is proposed and the related performances are numerically simulated. A preliminary experimental verification of the performances is reported.
Effects of molecular structure on microscopic heat transport in chain polymer liquids
Authors: Matsubara Hiroki , Kikugawa Gota , Bessho Takeshi , Yamashita Seiji , Ohara Taku
Published: April 2015

In this paper, we discuss the molecular mechanism of the heat conduction in a liquid, based on nonequilibrium molecular dynamics simulations of a systematic series of linear- and branched alkane liquids, as a continuation of our previous study on linear alkane [T. Ohara et al., J. Chem. Phys. 135, 034507 (2011)]. The thermal conductivities for these alkanes in a saturated liquid state at the same reduced temperature (0.7Tc) obtained from the simulations are compared in relation to the structural difference of the liquids. In order to connect the thermal energy transport characteristics with molecular structures, we introduce the new concept of the interatomic path of heat transfer (atomistic heat path, AHP), which is defined for each type of inter- and intramolecular interaction. It is found that the efficiency of intermolecular AHP is sensitive to the structure of the first neighbor shell, whereas that of intramolecular AHP is similar for different alkane species. The dependence of thermal conductivity on different lengths of the main and side chain can be understood from the natures of these inter- and intramolecular AHPs.
Phase-coherent transport and spin relaxation in InAs nanowires grown by molecule beam epitaxy
Authors: Wang L. B. , Guo J. K. , Kang N. , Pan Dong , Li Sen , Fan Dingxun , Zhao Jianhua , Xu H. Q.
Published: April 2015

We report low-temperature magnetotransport studies of individual InAs nanowires grown by molecule beam epitaxy. At low magnetic fields, the magnetoconductance characteristics exhibit a crossover between weak antilocalization and weak localization by changing either the gate voltage or the temperature. The observed crossover behavior can be well described in terms of relative scales of the transport characteristic lengths extracted based on the quasi-one-dimensional theory of weak localization in the presence of spin-orbit interaction. The spin relaxation length extracted from the magnetoconductance data is found to be in the range of 80–100 nm, indicating the presence of strong spin-orbit coupling in the InAs nanowires. Moreover, the amplitude of universal conductance fluctuations in the nanowires is found to be suppressed at low temperatures due to the presence of strong spin-orbit scattering.
Understanding the role of buried interface charges in a metal-oxide-semiconductor stack of Ti/Al2O3/Si using hard x-ray photoelectron spectroscopy
Authors: Church J. R. , Weiland C. , Opila R. L.
Published: April 2015

Hard X-ray photoelectron spectroscopy (HAXPES) analyses were carried out on metal-oxide-semiconductor (MOS) samples consisting of Si, thick and thin Al2O3, and a Ti metal cap. Using Si 1s and C 1s core levels for an energy reference, the Al 1s and Si 1s spectra were analyzed to reveal information about the location and roles of charges throughout the MOS layers. With different oxide thicknesses (2 nm and 23 nm), the depth sensitivity of HAXPES is exploited to probe different regions in the MOS structure. Post Ti deposition results indicated unexpected band alignment values between the thin and thick films, which are explained by the behavior of mobile charge within the Al2O3 layer.
Elastocaloric effect in ferroelectric ceramics
Authors: Chauhan Aditya , Patel Satyanarayan , Vaish Rahul
Published: April 2015

Elastocaloric effect has been experimentally demonstrated in bulk (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 polycrystalline ferroelectric material. Predictions were made using Maxwell's relationship for elastocaloric effect. A maximum elastocaloric effect of 1.55 K was observed for an initial material temperature of 340 K and applied compressive stress of 0–250 MPa (under a constant electric field of 2 MV m−1). The reported value is several times larger than the peak electrocaloric effect for the same material. The results indicate that ferroelectric materials possess a huge potential for elastocaloric refrigeration.
Chalcogen vacancies in monolayer transition metal dichalcogenides and Fermi level pinning at contacts
Authors: Guo Y. , Liu D. , Robertson J.
Published: April 2015

It is predicted that Schottky barriers of the transition metal dichalcogenides MoSe2, MoTe2, WS2, WSe2, and WTe2 will suffer less from Fermi level pinning by chalcogen vacancies than does MoS2, because their vacancy formation energies are larger. The reduction in vacancy numbers will allow a greater degree of Schottky barrier height tuning by varying metal work function of the contacts in these compounds. The vacancy levels of WS2, WSe2 and MoSe2, and MoTe2 are also calculated to lie nearer midgap, so that ambipolar conduction will be easier in these compounds than in MoS2.
Optical pulling of airborne absorbing particles and smut spores over a meter-scale distance with negative photophoretic force
Authors: Lin Jinda , Hart Adam G. , Li Yong-qing
Published: April 2015

We demonstrate optical pulling of single light-absorbing particles and smut spores in air over a meter-scale distance using a single collimated laser beam based on negative photophoretic force. The micron-sized particles are pulled towards the light source at a constant speed of 1–10 cm/s in the optical pulling pipeline while undergoing transverse rotation at 0.2–10 kHz. The pulled particles can be manipulated and precisely positioned on the entrance window with an accuracy of ∼20 μm, and their chemical compositions can be characterized with micro-Raman spectroscopy.
Optically confined polarized resonance Raman studies in identifying crystalline orientation of sub-diffraction limited AlGaN nanostructure
Authors: Sivadasan A. K. , Patsha Avinash , Dhara Sandip
Published: April 2015

An optical characterization tool of Raman spectroscopy with extremely weak scattering cross section tool is not popular to analyze scattered signal from a single nanostructure in the sub-diffraction regime. In this regard, plasmonic assisted characterization tools are only relevant in spectroscopic studies of nanoscale object in the sub-diffraction limit. We have reported polarized resonance Raman spectroscopic (RRS) studies with strong electron-phonon coupling to understand the crystalline orientation of a single AlGaN nanowire of diameter ∼100 nm. AlGaN nanowire is grown by chemical vapor deposition technique using the catalyst assisted vapor-liquid-solid process. The results are compared with the high resolution transmission electron microscopic analysis. As a matter of fact, optical confinement effect due to the dielectric contrast of nanowire with respect to that of surrounding media assisted with electron-phonon coupling of RRS is useful for the spectroscopic analysis in the sub-diffraction limit of 325 nm (λ/2N.A.) using an excitation wavelength (λ) of 325 nm and near ultraviolet 40× far field objective with a numerical aperture (N.A.) value of 0.50.
Large optical anisotropy for terahertz light of stacked graphene ribbons with slight asymmetry
Authors: Suzuki Satoru , Hibino Hiroki
Published: May 2015

The optical properties of stacked graphene microribbons in the terahertz region were simulated by the finite element method. The microribbons, which couple with terahertz light through the excitation of plasmons, were stacked with micrometer-scale vertical spacing (∼0.1λ or larger). Reflection and absorption spectra were found to strongly depend on the direction of incident light (forward or backward incidence), when the stacking structure was made slightly asymmetric by changing the ribbon width or the chemical potentials in each layer. At a certain frequency, light reflection is almost completely suppressed only for one incidence direction. The high directivity is considered to be due to the phasing effects of electromagnetic waves emitted from each layer like in a Yagi-Uda antenna.
Electrical performance of multilayer MoS2 transistors on high-κ Al2O3 coated Si substrates
Authors: Li Tao , Wan Bensong , Du Gang , Zhang Baoshun , Zeng Zhongming
Published: May 2015

The electrical performance of MoS2 can be engineered by introducing high-κ dielectrics, while the interactions between high-κ dielectrics and MoS2 need to be studied. In this study, multilayer MoS2 field-effect transistors (FETs) with a back-gated configuration were fabricated on high-κ Al2O3 coated Si substrates. Compared with MoS2 FETs on SiO2, the field-effect mobility (μFE) and subthreshold swing (SS) were remarkably improved in MoS2/Al2O3/Si. The improved μFE was thought to result from the dielectric screening effect from high-κ Al2O3. When a HfO2 passivation layer was introduced on the top of MoS2/Al2O3/Si, the field-effect mobility was further enhanced, which was thought to be concerned with the decreased contact resistance between the metal and MoS2. Meanwhile, the interface trap density increased from 2.4×1012 eV−1cm−2 to 6.3×1012 eV−1cm−2. The increase of the off-state current and the negative shift of the threshold voltage may be related to the increase of interface traps.
A stellar source of lithium is caught in the act
Authors: Miller Johanna L.
Published: May 2015

To explain the observed abundance of the light metallic element, astrophysical modelers have concluded that much of it was produced in stars. But direct evidence has been lacking until now.
Record-energy collisions coming soon at the LHC
Authors: Feder Toni
Published: May 2015

The machine that discovered the Higgs boson is flexing its muscles again. The results could be stunning new findings or striking new mysteries.
Foundations join forces to raise funds for basic research
Authors: Matthews Jermey N. A.
Published: May 2015

With federal funding in decline, philanthropists are stepping up to back risky projects, early-career researchers, and expensive scientific equipment.
Oximes in the Isoxazolone, Pyrazolone, and 1,2,3-Triazolone Series: Experimental and Computational Investigation of Energies and Structures of E/Z Isomers of α-Oxo-Oximes in the Gas Phase and in Solution
Authors: Koch Rainer , Wollweber Hans-Joachim , Wentrup Curt
Published: April 2015

The structures of a series of heterocyclic α-oxo-oximes, viz. 4-oximinoisoxazolone-5(4H)-ones 1 and 2,4-oximino-5(4H)-pyrazolones 3–5, and 4-oximino-1-phenyl-1,2,3-triazol-5(4H)-one 6, were investigated experimentally and computationally. Whereas the intramolecularly H-bonded ZZ isomers of these oximes are usually the most stable in the gas phase, this preference is overcome by intermolecular H-bonding to a solvent or another molecule. For 1,3-dimethyl-4-oximino-5(4H)-pyrazolone 3b a turnaround is seen when going from the solid (predominantly Z isomer) to DMSO solution (predominantly E isomer), which can be ascribed to an intermolecular H-bond between the oxime OH function and a DMSO molecule. Such isomerization is not seen in CDCl3, where intermolecular H-bonding is unimportant. The Z/E-isomerization in DMSO solution is accelerated by photolysis. Calculations of the energies of different conformers, and of 13C NMR data at the GIAO-ωb97xD/6-31G(d)//M06-2X/6-311++G(d,p) level permit a clear-cut correlation of conformer structures with observed 13C NMR spectra.
Use of the gonadotrophin-releasing hormone antagonist azaline B to control the oestrous cycle in the koala (Phascolarctos cinereus)
Authors: Ballantyne K. , Anderson S. T. , Pyne M. , Nicolson V. , Mucci A. , Lisle A. , Johnston S. D.
Published: May 2015

The present study examined the effectiveness of the gonadotrophin-releasing hormone (GnRH) antagonist azaline B to suppress plasma LH and 17β-oestradiol concentrations in koalas and its potential application for oestrous synchronisation. In Experiment 1, single subcutaneous injections of azaline B successfully blocked the LH response to exogenous mammalian (m) GnRH in a dose-dependent manner; specifically, 0 mg (n = 4) did not suppress the LH response, 1 mg azaline B (n = 6) suppressed the LH response for 24 h (P < 0.05), 3.3 mg azaline B (n = 8) suppressed the LH response significantly in all animals only for 3 h (P < 0.05), although in half the animals LH remained suppressed for up to 3 days, and 10 mg azaline B (n = 4) suppressed the LH response for 7 days (P < 0.05). In Experiment 2, daily 1 mg, s.c., injections of azaline B over a 10-day period during seasonal anoestrus (June–July; n = 6) suppressed (P < 0.01) the LH response to mGnRH consecutively over the 10-day treatment period and, 4 days after cessation of treatment, the LH response had not recovered. Experiment 3 was designed to test the efficacy of daily 1 mg, s.c., azaline B over 10 days to suppress plasma LH and 17β-oestradiol concentrations and ultimately synchronise timed return to oestrus during the breeding season. Although azaline B treatment did not suppress basal LH or 17β-oestradiol, oestrus was delayed in all treated females by 24.2 days, but with high variability (range 9–39 days). Overall, the present study demonstrates that the GnRH antagonist azaline B is able to inhibit the LH response in koalas to exogenous mGnRH and successfully delay the return to oestrus. However, although azaline B clearly disrupts folliculogenesis, it has not been able to effectively synchronise return to oestrus in the koala.
Genetically encoded sensors of protein hydrodynamics and molecular proximity
Authors: Hoepker Alexander C. , Wang Ariel , Le Marois Alix , Suhling Klaus , Yan Yuling , Marriott Gerard
Published: May 2015

Significance

The lumazine binding protein (LUMP) emits a cyan-colored fluorescence and has the longest average fluorescence lifetime of any genetically encoded fluorescent protein complex. Coupled with a small mass of 20 kDa, LUMP and its fusion with capture sequences are exploited as unique sensors of protein hydrodynamics and are shown to enable quantitative fluorescence anisotropy imaging of specific target proteins in vitro and in vivo. Moreover, the surface location of the lumazine probe is shown to improve the efficiency of Förster resonance energy transfer (FRET) with the Venus acceptor protein compared with CFP, which is used in the development of a new class of FRET-based sensor.
Structural details of the OxyR peroxide-sensing mechanism
Authors: Jo Inseong , Chung In-Young , Bae Hee-Won , Kim Jin-Sik , Song Saemee , Cho You-Hee , Ha Nam-Chul
Published: May 2015

Significance

In gram-negative bacteria, OxyR is the master peroxide sensor that regulates the transcription of defense genes in response to a low level of cellular H
2
O
2
via a rapid kinetic reaction. In this study, we present the first, to our knowledge, full-length structures of peroxide-sensing transcription regulator OxyR together with an oxidation intermediate-mimicking structure. The structures show all of the structural features describing the tetrameric assembly and a bound H
2
O
2
molecule near the conserved cysteine. Combining the structural results, we reveal a step-by-step molecular mechanism for OxyR from H
2
O
2
sensing to structural changes for transcriptional activation. Our study provides a structural basis for potentially answering key questions about the role of the cysteine residue in other Cys-based sensors, even mammalian ones, in response to various oxidants.
Making sense of sensory perceptions across languages and cultures
Authors: Caballero Rosario , Paradis Carita
Published: May 2015

This article has two aims: (i) to give an overview of research on sensory perceptions in different disciplines with different aims, and on the basis of that (ii) to encourage new research based on a balanced socio-sensory-cognitive approach. It emphasizes the need to study sensory meanings in human communication, both in Language with a capital L, focusing on universal phenomena, and across different languages, and within Culture with a capital C, such as parts of the world and political regions, and across different cultures, such as markets, production areas and aesthetic activities, in order to stimulate work resulting in more sophisticated, theoretically informed analyses of language use in general, and meaning-making of sensory perceptions in particular.
‘Flatten plus’: a recent implementation in WSxM for biological research
Authors: Gimeno Alejandro , Ares Pablo , Horcas Ignacio , Gil Adriana , Gómez-Rodríguez José M. , Colchero Jaime , Gómez-Herrero Julio
Published: May 2015

Summary: Scanning probe microscopy (SPM) is already a relevant tool in biological research at the nanoscale. We present ‘Flatten plus’, a recent and helpful implementation in the well-known WSxM free software package. ‘Flatten plus’ allows reducing low-frequency noise in SPM images in a semi-automated way preventing the appearance of typical artifacts associated with such filters.

Availability and implementation: WSxM is a free software implemented in C++ supported on MS Windows, but it can also be run under Mac or Linux using emulators such as Wine or Parallels. WSxM can be downloaded from http://www.wsxmsolutions.com/.

Contact:  ignacio.horcas@wsxmsolutions.com
Intraoperative Mean Arterial Pressure Variability and 30-day Mortality in Patients Having Noncardiac Surgery
Authors: Mascha Edward J. , Yang Dongsheng , Weiss Stephanie , Sessler Daniel I.
Published: May 2015

AbstractAbstract

Average mean arterial pressure and mean pressure variability were nonlinearly related to 30-day mortality in noncardiac surgical patients. After adjusting for time-weighted average mean arterial pressure and other important covariables, low blood pressure variability as measured by an improved formula was still associated with higher 30-day mortality, but the differences were not clinically important. Anesthesiologists might thus pay more attention to overall trends in the mean blood pressure for a case than in the minute-to-minute variation.

Background:

Little is known about the relationship between intraoperative blood pressure variability and mortality after noncardiac surgery. Therefore, the authors tested the hypothesis that blood pressure variability, independent from absolute blood pressure, is associated with increased 30-day mortality.

Methods:

Baseline and intraoperative variables plus 30-day mortality were obtained for 104,401 adults having noncardiac surgery lasting 60 min or longer. In confounder-adjusted models, the authors evaluated the associations between 30-day mortality and both time-weighted average intraoperative mean arterial pressure (TWA-MAP) and measures of intraoperative MAP variability—including generalized average real variability of MAP (ARV-MAP) and SD of MAP (SD-MAP).

Results:

Mean ± SD TWA-MAP was 84 ± 10 mmHg, and ARV-MAP was 2.5 ± 1.3 mmHg/min. TWA-MAP was strongly related to 30-day mortality, which more than tripled as TWA-MAP decreased from 80 to 50 mmHg. ARV-MAP was only marginally related to 30-day mortality (P = 0.033) after adjusting for TWA-MAP. Compared with median ARV-MAP, odds ratio (95% CI) for 30-day mortality was 1.14 (1.03 to 1.25) for low ARV-MAP (first quartile) and 0.94 (0.88 to 0.99) for high ARV-MAP (third quartile). Odds of 30-day mortality decreased as five-level categorized ARV-MAP increased (0.92; 0.87 to 0.99 for one category increase; P = 0.015). Secondarily, cumulative duration of MAP less than 50, 55, 60, 70, and 80 mmHg was associated with increased odds of 30-day mortality (all P < 0.001).

Conclusion:

Although lower mean arterial pressure is strongly associated with mortality, lower intraoperative blood pressure variability per se is only mildly associated with postoperative mortality after noncardiac surgery.
Mycophenolate-Induced Posterior Reversible Encephalopathy Syndrome
Authors: Khajuria Bhavik , Khajuria Mansi , Agrawal Yashwant
Published: May 2015

A 29-year-old woman presented with diffuse anasarca and shortness of breath. Workup revealed a creatinine of 3.3 and a glomerular filtration rate of 17. The patient was also found to be pancytopenic with evidence of hemolytic anemia. A renal biopsy showed evidence of stage IV lupus nephritis with rapidly progressive glomerulonephritis. Her lupus was further classified as ANA negative and anti-dsDNA positive. Mycophenolate and triweekly hemodialysis were started along with a steroid burst of methylprednisolone 1 g for 3 days followed by prednisone 60 mg daily. Four days after discharge, the patient represented with a witnessed 3-minute seizure involving bowel incontinence, altered mental status, and tongue biting. She was given 2 mg intravenous lorazepam and loaded with 1000 mg levetiracetam for seizure prophylaxis. Magnetic resonance imaging of the head revealed bilateral posterior hemispheric subcortical edema, and the diagnosis of posterior reversible encephalopathy syndrome was made. Mycophenolate was immediately discontinued and replaced with cyclophosphamide. Strict blood pressure control below 140/90 mm Hg was maintained initially with intravenous nicardipine drip and then transitioned to oral nifedipine, clonidine, losartan, and minoxidil. A repeat head magnetic resonance imaging 8 days later showed resolved subcortical edema consistent with the patient's improved mental status. No permanent neurologic sequelae were recorded as a result of this hospital episode.
Selection for Intermediate Genotypes Enables a Key Innovation in Phage Lambda
Authors: Burmeister Alita R. , Lenski Richard E. , Meyer Justin R.
Published: April 2015

The evolution of qualitatively new functions is fundamental for shaping the diversity of life. Such innovations are rare because they require multiple coordinated changes. We sought to understand the evolutionary processes involved in a particular key innovation, whereby phage λ evolved the ability to exploit a novel receptor, OmpF, on the surface ofEscherichia colicells. Previous work has shown that this transition repeatedly evolves in the laboratory, despite requiring four mutations in specific regions of a single gene. Here we examine how this innovation evolved by studying six intermediate genotypes that arose during independent transitions to use OmpF. In particular, we tested whether these genotypes were favored by selection, and how a coevolved change in the hosts influenced the fitness of the phage genotypes. To do so, we measured the fitness of the intermediate types relative to the ancestral λ when competing for either ancestral or coevolved host cells. All six intermediates had improved fitness on at least one host, and four had higher fitness on the coevolved host than on the ancestral host. These results show that the evolution of the phage’s new ability to use OmpF was repeatable because the intermediate genotypes were adaptive and, in many cases, because coevolution of the host favored their emergence.
Climatic niches in phylogenetic comparative studies: a review of challenges and approaches
Authors: Budic Lara , Dormann Carsten
Published: May 2015

Studying the evolution of climatic niches through time in a phylogenetic comparative framework combines species distribution modeling with phylogenies. Phylogenetic comparative studies aid the understanding of the evolution of species' environmental preferences by revealing the underlying evolutionary processes and causes, detecting the differences among groups of species or relative to evolutionary pattern of other phenotypic traits, but also act as a yardstick to gauge the adaptational potential under climate change. Because several alternatives exist on how to compute and represent the climatic niche, we here review and discuss the current state of the art and propose a best practice to use in comparative studies. Moreover we outline the common evolutionary models and available model-fitting methods and describe the procedure for ancestral niche reconstruction with the intention to give a broad overview and highlight the most advanced approaches for optimal niche-related comparative studies.