bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Glutathione Peroxidase and KCNJ11 Gene Polymorphisms in Patients with New Onset Diabetes Mellitus After Renal Transplantation
Authors: Yalin Gulsah , Akgul Sebahat , Tanrikulu Seher , Purisa Sevim , Gul Nurdan , Uzum Ayse , Sarvan Fatma , Sever Mehmet , Satman Ilhan
Published: January 2017

Introduction Genetic mutations such as C599T polymorphism in glutathione peroxidase [GPX1] gene and polymorphisms in potassium channel (KCNJ11) genes have recently been proposed in the etiopathogenesis of new onset diabetes mellitus after renal transplantation (NODAT). We aimed to examine the association of GPX1 and KCNJ11 polymorphisms in NODAT.

Materials and Methods This is a monocenter case-control study with a total of 118 renal transplant recipients who were divided into 2 groups; NODAT and normal glucose tolerance. Relation of GPX1 and KCNJ11 polymorphisms were investigated between these groups. PCR-RFLP method was used for genotyping of polymorphisms in the GPX1 (rs1050450) and KCNJ11 (rs1805127) genes. Two alleles were visualized for each gene (C/T for GPX1 and A/G for KCNJ11).

Results NODAT was correlated with age at transplantation (p<0.001, r=0.380), post-transplant systolic blood pressure (BP) (p=0.02, r=0.211), post-transplant non-HDL cholesterol levels (p=0.01, r=0.803), degree of weight change at the end of the first year (p=0.01, r=0.471), presence of pre-transplant hypertension (HT) (p=0.02, r=0.201), family history of diabetes (p=0.01, r=0.29) and dyslipidemia (p=0.012, r=0.362). GPX1 polymorphism of TT (mutant) allele was significantly more frequent in patients with NODAT (p<0.001, r=0.396) independent from other diabetogenic risk factors. KCNJ11 polymorphisms were similar in both groups and did not show any significant association with NODAT (p=0.10).

Conclusions In addition to several diabetogenic risk factors, C599T polymorphisms in GPX1 gene might also contribute to the development of NODAT. Further studies on larger patient series are necessary in order to reach definitive suggestions.
How can mentoring support women in a male-dominated workplace? A case study of the UK police force
Authors: Jones Jenni
Published: January 2017

There is little academic research in relation to mentoring, learning and women, particularly in the male-dominated organizational context of the UK Police force. Currently, there is a Home Office drive to address inequality within the UK Police with a number of initiatives proposed including mentoring interventions, flexible working arrangements and positive-action recruitment initiatives. The purpose of this study is to investigate what policewomen mentees and mentors perceive they are learning through formal mentoring over time and how this makes a difference for them in the workplace. This will provide insights into whether Government investment in formal mentoring is the right intervention to help create a more gender-reflective, more equal workforce, in the Police. This study takes a critical realist position and an interpretivist theoretical perspective investigating a single case study organization. Key themes, spread across the four phases of the mentoring lifecycle were explored through 68 semi-structured interviews and four focus groups. Key findings are uncovered in relation to learning outcomes for these policewomen, both as mentees and mentors. It was found that mentoring added value across all four learning domains (cognitive, skills, affective-related and social networks) and that the largest number of responses over time, were in relation to the affective-related domain, particularly building self-confidence. These findings are significant as they demonstrate that formal mentoring programmes can support and empower women within the specific workplace of the UK Police. In conclusion, if women are being precluded from breaking the “glass labyrinth” because of lack of knowledge, opportunity and networks to progress within this context, then mentoring could be part of this solution. If the masculine organizational culture is also creating prejudice and obstacles for women in the workplace (the “concrete floor”), then mentoring might be one way towards breaking down these barriers. In addition, if all (or some) of these factors are contributing to women’s lower self-confidence levels and the “sticky floor” syndrome, then again the findings suggest that mentoring may be part of the solution towards empowering women beyond their current role. It is hoped that these insights will impact the emphasis put on the various Home Office recommendations and the initiatives offered by different Police forces. It is also hoped that these insights will have implications for other organizations that are considering investing in mentoring interventions, for similar groups or beyond. This article is published as part of a collection on the role of women in management and the workplace.
Colloidal transport by active filaments
Authors: Manna Raj Kumar , Kumar P. B. Sunil , Adhikari R.
Published: January 2017

Enhanced colloidal transport beyond the limit imposed by diffusion is usually achieved through external fields. Here, we demonstrate the ballistic transport of a colloidal sphere using internal sources of energy provided by an attached active filament. The latter is modeled as a chain of chemo-mechanically active beads connected by potentials that enforce semi-flexibility and self-avoidance. The fluid flow produced by the active beads and the forces they mediate are explicitly taken into account in the overdamped equations of motion describing the colloid-filament assembly. The speed and efficiency of transport depend on the dynamical conformational states of the filament. We characterize these states using filament writhe as an order parameter and identify ones yielding maxima in speed and efficiency of transport. The transport mechanism reported here has a remarkable resemblance to the flagellar propulsion of microorganisms which suggests its utility in biomimetic systems.
More room for microphase separation: An extended study on binary liquids confined in SBA-15 cylindrical pores
Authors: Mhanna Ramona , Abdel Hamid Abdel Razzak , Dutta Sujeet , Lefort Ronan , Noirez Laurence , Frick Bernhard , Morineau Denis
Published: January 2017

The confinement of liquid mixtures in porous channels provides new insight into fluid ordering at the nanoscale. In this study, we address a phenomenon of microphase separation, which appears as a novel fascinating confinement effect for fully miscible binary liquids. We investigate the structure of tert-butanol-toluene mixtures confined in the straight and mono-dispersed cylindrical nanochannels of SBA-15 mesoporous silicates (D = 8.3 nm). Small angle neutron scattering experiments on samples with carefully designed isotopic compositions are performed to systematically vary the scattering length density of the different compounds and assess the radial concentration profile of the confined phases. The resulting modulation of the Bragg reflections of SBA-15 is compared with the predictions from different core-shell models, highlighting a molecular-scale phase-separated tubular structure with the tert-butanol forming a layer at the pore surface, surrounding a toluene-rich core. The present structural study suggests that the microphase separation phenomenon in confinement, which so far had only been reported for a smaller pore size (D = 3.65 nm) and a unique mixture composition, must be considered as a general phenomenon. It also highlights the strength of neutron scattering method with isotopic substitution, which is a unique experimental approach to reveal this phenomenon.
Effects of incident N atom kinetic energy on TiN/TiN(001) film growth dynamics: A molecular dynamics investigation
Authors: Edström D. , Sangiovanni D. G. , Hultman L. , Petrov I. , Greene J. E. , Chirita V.
Published: January 2017

Large-scale classical molecular dynamics simulations of epitaxial TiN/TiN(001) thin film growth at 1200 K, a temperature within the optimal range for epitaxial TiN growth, with an incident N-to-Ti flux ratio of four, are carried out using incident N energies EN = 2 and 10 eV and incident Ti energy ETi = 2 eV. To further highlight the effect of EN, we grow a bilayer film with EN = 2 eV initially and then switch to EN = 10 eV. As-deposited layers are analyzed as a function of composition, island-size distribution, island-edge orientation, and vacancy formation. Results show that growth with EN = 2 eV results in films that are globally overstoichiometric with islands bounded by N-terminated polar 110 edges, whereas films grown with EN = 10 eV are flatter and closer to stoichiometric. However, EN = 10 eV layers exhibit local N deficiency leading to the formation of isolated 111-oriented islands. Films grown by changing the incident energy from 2 to 10 eV during growth are more compact than those grown entirely with EN = 2 eV and exhibit greatly reduced concentrations of upper-layer adatoms, admolecules, and small clusters. Islands with 110 edges formed during growth with EN = 2 eV transform to islands with 100 edges as EN is switched to 10 eV.
Molecular collisions and reactive scattering in external fields: Are field-induced couplings important at short range?
Authors: Vieira D. , Krems R. V. , Tscherbul T. V.
Published: January 2017

We use accurate quantum scattering calculations to elucidate the role of short-range molecule-field interactions in atom-molecule inelastic collisions and abstraction chemical reactions at low temperatures. We consider two examples: elastic and inelastic scattering of NH(Σ3) molecules with Mg(S1) atoms in a magnetic field; reactive scattering LiF + H → Li + HF in an electric field. Our calculations suggest that, for non-reactive collision systems and abstraction chemical reactions, the molecule-field interactions cannot generally be neglected at short range because the atom-molecule potential passes through zero at short range. An important exception occurs for Zeeman transitions in atom-molecule collisions at magnetic fields ≲1000 G, for which the molecule-field couplings need only be included at large ρ outside the range of the atom-molecule interaction. Our results highlight the importance of an accurate description of ρ-dependent molecule-field interactions in quantum scattering calculations on molecular collisions and chemical reactions at low temperatures.
Extended defects in ZnO: Efficient sinks for point defects
Authors: Azarov Alexander , Rauwel Protima , Hallén Anders , Monakhov Edouard , Svensson Bengt G.
Published: January 2017

Dopant-defect reactions dominate the defect formation in mono-crystalline ZnO samples implanted with Ag and B ions. This is in contrast to most other ion species studied and results in an enhanced concentration of extended defects, such as stacking faults and defect clusters. Using a combination of B and Ag implants and diffusion of residual Li atoms as a tracer, we demonstrate that extended defects in ZnO act as efficient traps for highly mobile Zn interstitials. The results imply that dynamic annealing involving interaction of point defects with extended ones can play a key role in the disorder saturation observed for ZnO and other radiation-hard semiconductors implanted with high doses.
The volume of Gaussian states by information geometry
Authors: Felice Domenico , Quang Minh Hà , Mancini Stefano
Published: January 2017

We formulate the problem of determining the volume of the set of Gaussian physical states in the framework of information geometry. This is done by considering phase space probability distributions parametrized by their covariances and endowing the resulting statistical manifold with the Fisher-Rao metric. We then evaluate the volume of classical, quantum, and quantum entangled states for two-mode systems, showing chains of strict inclusions.
Superconducting properties of Ba(Fe1–xNix)2As2 thin films in high magnetic fields
Authors: Richter Stefan , Kurth Fritz , Iida Kazumasa , Pervakov Kirill , Pukenas Aurimas , Tarantini Chiara , Jaroszynski Jan , Hänisch Jens , Grinenko Vadim , Skrotzki Werner , Nielsch Kornelius , Hühne Ruben
Published: January 2017

We report on the electrical transport properties of epitaxial Ba(Fe1–xNix)2As2 thin films grown by pulsed laser deposition in static magnetic fields up to 35 T. The thin film shows a critical temperature of 17.2 K and a critical current density of 5.7 × 105 A/cm2 in self field at 4.2 K, while the pinning is dominated by elastic pinning at two-dimensional nonmagnetic defects. Compared to the single-crystal data, we find a higher slope of the upper critical field for the thin film at a similar doping level and a small anisotropy. Also, an unusual small vortex liquid phase was observed at low temperatures, which is a striking difference to Co-doped BaFe2As2 thin films.
Exploring the nonlinear cloud and rain equation
Authors: Koren Ilan , Tziperman Eli , Feingold Graham
Published: January 2017

Marine stratocumulus cloud decks are regarded as the reflectors of the climate system, returning back to space a significant part of the income solar radiation, thus cooling the atmosphere. Such clouds can exist in two stable modes, open and closed cells, for a wide range of environmental conditions. This emergent behavior of the system, and its sensitivity to aerosol and environmental properties, is captured by a set of nonlinear equations. Here, using linear stability analysis, we express the transition from steady to a limit-cycle state analytically, showing how it depends on the model parameters. We show that the control of the droplet concentration (N), the environmental carrying-capacity (H0), and the cloud recovery parameter (τ) can be linked by a single nondimensional parameter (μ=N/(ατH0)), suggesting that for deeper clouds the transition from open (oscillating) to closed (stable fixed point) cells will occur for higher droplet concentration (i.e., higher aerosol loading). The analytical calculations of the possible states, and how they are affected by changes in aerosol and the environmental variables, provide an enhanced understanding of the complex interactions of clouds and rain.
Efficient free energy calculations by combining two complementary tempering sampling methods
Authors: Xie Liangxu , Shen Lin , Chen Zhe-Ning , Yang Mingjun
Published: January 2017

Although energy barriers can be efficiently crossed in the reaction coordinate (RC) guided sampling, this type of method suffers from identification of the correct RCs or requirements of high dimensionality of the defined RCs for a given system. If only the approximate RCs with significant barriers are used in the simulations, hidden energy barriers with small to medium height would exist in other degrees of freedom (DOFs) relevant to the target process and consequently cause the problem of insufficient sampling. To address the sampling in this so-called hidden barrier situation, here we propose an effective approach to combine temperature accelerated molecular dynamics (TAMD), an efficient RC-guided sampling method, with the integrated tempering sampling (ITS), a generalized ensemble sampling method. In this combined ITS-TAMD method, the sampling along the major RCs with high energy barriers is guided by TAMD and the sampling of the rest of the DOFs with lower but not negligible barriers is enhanced by ITS. The performance of ITS-TAMD to three systems in the processes with hidden barriers has been examined. In comparison to the standalone TAMD or ITS approach, the present hybrid method shows three main improvements. (1) Sampling efficiency can be improved at least five times even if in the presence of hidden energy barriers. (2) The canonical distribution can be more accurately recovered, from which the thermodynamic properties along other collective variables can be computed correctly. (3) The robustness of the selection of major RCs suggests that the dimensionality of necessary RCs can be reduced. Our work shows more potential applications of the ITS-TAMD method as the efficient and powerful tool for the investigation of a broad range of interesting cases.
Fokker–Planck quantum master equation for mixed quantum–semiclassical dynamics
Authors: Ding Jin-Jin , Wang Yao , Zhang Hou-Dao , Xu Rui-Xue , Zheng Xiao , Yan YiJing
Published: January 2017

We revisit Caldeira–Leggett’s quantum master equation representing mixed quantum–classical theory, but with limited applications. Proposed is a Fokker–Planck quantum master equation theory, with a generic bi–exponential correlation function description on semiclassical Brownian oscillators’ environments. The new theory has caustic terms that bridge between the quantum description on primary systems and the semiclassical or quasi–classical description on environments. Various parametrization schemes, both analytical and numerical, for the generic bi–exponential environment bath correlation functions are proposed and scrutinized. The Fokker–Planck quantum master equation theory is of the same numerical cost as the original Caldeira–Leggett’s approach but acquires a significantly broadened validity and accuracy range, as illustrated against the exact dynamics on model systems in quantum Brownian oscillators’ environments, at moderately low temperatures.
Droplet growth during vapor-liquid transition in a 2D Lennard-Jones fluid
Authors: Midya Jiarul , Das Subir K.
Published: January 2017

Results for the kinetics of vapor-liquid phase transition have been presented from the molecular dynamics simulations of a single component two-dimensional Lennard-Jones fluid. The phase diagram for the model, primary prerequisite for this purpose, has been obtained via the Monte Carlo simulations. Our focus is on the region very close to the vapor branch of the coexistence curve. Quenches to such region provide morphology that consists of disconnected circular clusters in the vapor background. We identified that these clusters exhibit diffusive motion and grow via sticky collisions among them. The growth follows power-law behavior with time, exponent of which is found to be in nice agreement with a theoretical prediction.
Relationship between the structure and optical properties of lithium tantalate at the zero-birefringence point
Authors: Huband S. , Keeble D. S. , Zhang N. , Glazer A. M. , Bartasyte A. , Thomas P. A.
Published: January 2017

The structure of lithium tantalate powders has been investigated using neutron diffraction between room temperature and 445 K, which includes the zero-birefringence point. As the temperature increases, the displacement of the Ta atom from the centre of the O octahedra and the tilt of the octahedra both decrease linearly in the range investigated. The measured structures form the basis of a range of density functional theory calculations utilizing the WIEN2 k code, with a focus on calculating the optical properties. These calculations are sensitive to the small structural changes measured in this temperature range; the calculated birefringence changes are consistent with the changes measured experimentally. Further, by investigating the effect of each atom in isolation, it can be shown that the birefringence of lithium tantalate mainly depends on the Ta displacement and the octahedral tilt, with the linear change in these as a function of temperature producing the change in birefringence with temperature, which results in it becoming zero-birefringent. This work demonstrates the unique material insights that can be obtained by combining density functional calculations with precise structural studies.
Study of graphene growth on copper foil by pulsed laser deposition at reduced temperature
Authors: Abd Elhamid Abd Elhamid M. , Hafez Mohamed A. , Aboulfotouh Abdelnaser M. , Azzouz Iftitan M.
Published: January 2017

Graphene has been successfully grown on commercial copper foil at low temperature of 500 °C by pulsed laser deposition (PLD). X-ray diffraction patterns showed that films have been grown in the presence of Cu(111) and Cu(200) facets. Raman spectroscopy was utilized to study the effects of temperature, surface structure, and cooling rate on the graphene growth. Raman spectra indicate that the synthesis of graphene layers rely on the surface quality of the Cu substrate together with the proper cooling profile coupled with graphene growth temperature. PLD-grown graphene film on Cu has been verified by transmission electron microscopy. Surface mediated growth of graphene on Cu foil substrate revealed to have a favorable catalytic effect. High growth rate of graphene and less defects can be derived using fast cooling rate.
Fermi-level pinning and intrinsic surface states of Al1−xInxN(101¯) surfaces
Authors: Portz V. , Schnedler M. , Lymperakis L. , Neugebauer J. , Eisele H. , Carlin J.-F. , Butté R. , Grandjean N. , Dunin-Borkowski R. E. , Ebert Ph.
Published: January 2017

The electronic structure of Al1−xInxN(101¯0) surfaces is investigated by cross-sectional scanning tunneling spectroscopy and density functional theory calculations. The surface exhibits empty Al and/or In-derived dangling bond states, which are calculated to be within the fundamental bulk band gap for In compositions smaller than 60%. The energy of the lowest empty In-derived surface state is extracted from the tunnel spectra for lattice-matched Al1–xInxN with In compositions of x = 0.19 and x = 0.20 to be EC − 1.82 ± 0.41 and EC − 1.80 ± 0.56 eV, respectively, in good agreement with the calculated energies. Under growth conditions, the Fermi level is hence pinned (unpinned) for In compositions smaller (larger) than 60%. The analysis of the tunnel spectra suggests an electron affinity of ∼3.5 eV for nonpolar lattice-matched Al1–xInxN cleavage surfaces, which is large compared to linearly interpolated values of polar AlN and InN (0001) surfaces.
All-optical switching via four-wave mixing Bragg scattering in a silicon platform
Authors: Zhao Yun , Lombardo David , Mathews Jay , Agha Imad
Published: January 2017

We employ the process of non-degenerate four-wave mixing Bragg scattering to demonstrate all-optical control in a silicon platform. In our configuration, a strong, non-information-carrying pump is mixed with a weak control pump and an input signal in a silicon-on-insulator waveguide. Through the optical nonlinearity of this highly confining waveguide, the weak pump controls the wavelength conversion process from the signal to an idler, leading to a controlled depletion of the signal. The strong pump, on the other hand, plays the role of a constant bias. In this work, we show experimentally that it is possible to implement this low-power switching technique as a first step towards universal optical logic gates, and test the performance with random binary data. Even at very low powers, where the signal and control pump levels are almost equal, the eye-diagrams remain open, indicating a successful operation of the logic gates.
Slow electrostatic fluctuations generated by beam-plasma interaction
Authors: Pommois Karen , Valentini Francesco , Pezzi Oreste , Veltri Pierluigi
Published: January 2017

Eulerian simulations of the Vlasov-Poisson equations have been employed to analyze the excitation of slow electrostatic fluctuations (with phase speed close to the electron thermal speed), due to a beam-plasma interaction, and their propagation in linear and nonlinear regimes. In 1968, O'Neil and Malmberg [Phys. Fluids 11, 1754 (1968)] dubbed these waves “beam modes.” In the present paper, previous analytical results on the beam modes in both linear and nonlinear regimes have been revisited numerically, pointing out that, when an electron beam is launched in a plasma of Maxwellian electrons and motionless protons and this initial equilibrium is perturbed by a monochromatic density disturbance, the electric field amplitude grows exponentially in time and then undergoes nonlinear saturation, associated with the kinetic effects of particle trapping and phase space vortex generation. Moreover, new numerical results give evidence that, when the initial density perturbation is setup in the form of a low amplitude random phase noise, the whole Fourier spectrum of wavenumbers is excited. As a result, the electric field profile appears as a train of isolated pulses, each of them being associated with a phase space vortex in the electron distribution function. At later times, these vortical structures tend to merge and, correspondingly, the electric pulses collapse, showing the tendency towards a time asymptotic configuration characterized by the appearance of electric soliton-like pulses. This dynamical evolution is driven by purely kinetic processes, possibly at work in many space and laboratory plasma environments.
Double antinode excited quartz-enhanced photoacoustic spectrophone
Authors: Zheng Huadan , Dong Lei , Patimisco Pietro , Wu Hongpeng , Sampaolo Angelo , Yin Xukun , Li Shangzhi , Ma Weiguang , Zhang Lei , Yin Wangbao , Xiao Liantuan , Spagnolo Vincenzo , Jia Suotang , Tittel Frank K.
Published: January 2017

A double antinode excited quartz-enhanced photoacoustic spectroscopy (DAE-QEPAS) spectrophone, employing a custom-made quartz tuning fork (QTF) and operating at the 1stt overtone resonance mode is reported. The signal phase variation along the QTF prong was investigated, and a piezoelectric transducer was introduced to compensate the phase shift between two QTF separated 1st overtone antinode points. Two sets of acoustic micro-resonators were optimized and assembled at two antinode points to improve the spectrophone performance. With the two antinodes excited by one laser source, the DAE-QEPAS spectrophone attained a sensitivity gain factor of ∼100 times and ∼3 times with respect to the 1st overtone resonances of a bare custom QTF and a standard on-beam QEPAS spectrophone, respectively. H2O was selected as the target analyte and a detection limit of ∼230 ppb was obtained by the DAE-QEPAS spectrophone for a 1 s integration time, corresponding to a normalized noise equivalent absorption coefficient of 1.73 × 10-9 cm−1·W·Hz−1/2.
Tuning of perovskite solar cell performance via low-temperature brookite scaffolds surface modifications
Authors: Singh Trilok , Udagawa Yosuke , Ikegami Masashi , Kunugita Hideyuki , Ema Kazuhiro , Miyasaka Tsutomu
Published: January 2017

The nature of metal oxide scaffold played a pivotal role for the growth of high quality perovskites and subsequently facilitates efficient photovoltaics devices. We demonstrate an effective way to fabricate a low-temperature TiO2 brookite scaffold layer with a uniform and pinhole-free layer for enhancing photovoltaic properties of perovskite solar cells. Various concentrations of TiCl4 were used to modify brookite TiO2 for efficient charge generation and fast charge extraction. We observed that the brookite layer with an appropriate TiCl4 treatment possesses a smooth surface with full coverage of the substrates, whereas TiCl4 treatment further improves the contact of the TiO2/perovskite interface which facilitates charge extraction and drastically influenced charge recombination. The surface treated brookite scaffolds perovskite devices showed an improved performance with an average power conversion efficiency more than 17%. The time resolved photoluminescence showed that the treated samples have obvious effect on the charge carrier dynamics. The striking observation of this study was very low appearance of hysteresis and high reproducibility in the treated samples, which opens up the possibilities for the fabrication of high efficient devices at relatively low temperatures with negligible hysteresis via facile surface modifications.
Origin of variation of shift field via annealing at 400°C in a perpendicular-anisotropy magnetic tunnel junction with [Co/Pt]-multilayers based synthetic ferrimagnetic reference layer
Authors: Honjo H. , Ikeda S. , Sato H. , Watanebe T. , Miura S. , Nasuno T. , Noguchi Y. , Yasuhira M. , Tanigawa T. , Koike H. , Muraguchi M. , Niwa M. , Ito K. , Ohno H. , Endoh T.
Published: January 2017

We investigated properties of perpendicular-anisotropy magnetic tunnel junctions (p-MTJs) with [Co/Pt]-multilayer based synthetic ferrimagnetic reference (SyF) layer at elevated annealing temperature Ta from 350°C to 400°C. Shift field HS defined as center field of minor resistance versus magnetic field curve of the MTJs increased with increase of Ta from 350°C to 400°C. The variation of HS is attributed to the variation of saturation magnetic moment in the SyF reference layer. Cross sectional energy dispersive X-ray spectroscopy analysis revealed that Fe element of CoFeB in the reference layer diffuses to Co/Pt multilayers in the SyF reference layer.
Superior characteristics of microscale light emitting diodes through tightly lateral oxide-confined scheme
Authors: Huang Shen-Che , Li Heng , Zhang Zhe-Han , Chen Hsiang , Wang Shing-Chung , Lu Tien-Chang
Published: January 2017

We report on the design of the geometry and chip size–controlled structures of microscale light-emitting diodes (micro-LEDs) with a shallow-etched oxide-refilled current aperture and their performance. The proposed structure, which combines an indium-tin-oxide layer and an oxide-confined aperture, exhibited not only uniform current distribution but also remarkably tight current confinement. An extremely high injection level of more than 90 kA/cm2 was achieved in the micro-LED with a 5-μm aperture. Current spreading and the droop mechanism in the investigated devices were characterized through electroluminescence measurements, optical microscopy, and beam-view imaging. Furthermore, we utilized the β-model and S-model to elucidate current crowding and the efficiency droop phenomenon in the investigated micro-LEDs. The luminescence results evidenced the highly favorable performance of the fabricated micro-LEDs, which is a result of their more uniform current spreading and lower junction temperature relative to conventional LEDs. Moreover, the maximum endured current density could be further increased by reducing the aperture size of the micro-LEDs. The proposed design, which is expected to be beneficial for the development of high-performance array-based micro-LEDs, is practicable through current state-of-the-art processing techniques.
Localized tail state distribution and hopping transport in ultrathin zinc-tin-oxide thin film transistor
Authors: Li Jeng-Ting , Liu Li-Chih , Chen Jen-Sue , Jeng Jiann-Shing , Liao Po-Yung , Chiang Hsiao-Cheng , Chang Ting-Chang , Nugraha Mohamad Insan , Loi Maria Antonietta
Published: January 2017

Carrier transport properties of solution processed ultra thin (4 nm) zinc-tin oxide (ZTO) thin film transistor are investigated based on its transfer characteristics measured at the temperature ranging from 310 K to 77 K. As temperature decreases, the transfer curves show a parellel shift toward more postive voltages. The conduction mechanism of ultra-thin ZTO film and its connection to the density of band tail states have been substantiated by two approaches, including fitting logarithm drain current (log ID) to T−1/3 at 310 K to 77 K according to the two-dimensional Mott variable range hopping theory and the extraction of density of localized tail states through the energy distribution of trapped carrier density. The linear dependency of log ID vs. T−1/3 indicates that the dominant carrier transport mechanism in ZTO is the variable range hopping. The extracted value of density of tail states at the conduction band minimum is 4.75 × 1020 cm−3 eV−1 through the energy distribution of trapped carrier density. The high density of localized tail states in the ultra thin ZTO film is the key factor leading to the room-temperature hopping transport of carriers among localized tail states.
Materials growth and band offset determination of Al2O3/In0.15Ga0.85Sb/GaSb/GaAs heterostructure grown by metalorganic chemical vapor deposition
Authors: Huynh Sa Hoang , Ha Minh Thien Huu , Do Huy Binh , Nguyen Tuan Anh , Luc Quang Ho , Chang Edward Yi
Published: January 2017

The ternary InxGa1-xSb epilayers grown on GaAs substrates by metalorganic chemical vapor deposition using a GaSb buffer layer have been demonstrated. High–resolution transmission electron microscopy micrographs illustrate an entirely relaxed GaSb buffer grown by the interfacial misfit dislocation growth mode. A high quality In0.15Ga0.85Sb epilayer was obtained on the GaSb surface with the very low threading dislocation densities (∼8.0 × 106 cm−2) and the surface roughness was 0.87 nm. The indium content of the InxGa1-xSb epilayer depends significantly on the growth temperature and approaches to a saturated value of 15% when the growth temperature was above 580 °C. Based on the X-ray photoelectron spectroscopy analyses, the valence band offset and the conduction band offset of Al2O3 with the In0.15Ga0.85Sb/GaSb/GaAs heterostructure are 3.26 eV and 2.91 eV, respectively. In addition, from the O1s energy-loss spectrum analysis, the band gap of Al2O3 is found to be ∼6.78 ± 0.05 eV.
Tailoring perpendicular magnetic coupling by XMCD
Authors: Idzerda Y. U. , Snow R. , Bhatkar H. , N’Diaye A. T. , Arenholz E. A.
Published: January 2017

The elemental perpendicular magnetic anisotropy constants of both elements of a 20 nm bcc Co88Mn12 alloy film grown on MgO(001) and capped with Al, have been determined. By fitting a Stoner-Wohlfarth astroid model to the measured Co and Mn L3 XMCD peak intensities as a function of incidence photon angle with the magnetic field applied co-axially with the photon propagation direction, the elemental perpendicular anisotropy constants were found to be −6.46 x 105 J/m3 and −6.68 x 105 J/m3, respectively. The modeling of the Co and Mn data both result in nearly the same anisotropy constant as expected for a single alloy film.
The magnetically driven plasma jet produces a pressure of 33 GPa on PTS
Authors: Xu Qiang , Dan Jiakun , Wang Guilin , Guo Shuai , Zhang Siqun , Cai Hongchun , Ren Xiao , Wang Kunlun , Zhou Shaotong , Zhang Zhaohui , Huang Xianbin
Published: January 2017

We report on experiments in which a magnetically driven plasma jet was used to hit a 500 μm thick planar aluminum target. The plasma jet was produced by using a 50 μm thick aluminum radial foil, which was subjected to 4 MA, 90 ns rising time current on the primary test stand pulsed power facility. The subsequent magnetic bubbles propagate with radial velocity reaching 200 km/s and an axial velocity of 230 km/s. After the plasma knocks onto the target, a shock forms in the target. When the shock gets to the backside of the target, we measure the velocity of the moving surface using dual laser heterodyne velocimetry. By using the Hugoniot relations, we know that the plasma jet produced a pressure of 33 GPa. According to the measured pressure and the velocity of the plasma jet, the density of the jet can be also roughly estimated.
Transmission and refractive index sensing based on Fano resonance in MIM waveguide-coupled trapezoid cavity
Authors: Zhou Jinli , Chen Huibin , Zhang Zhidong , Tang Jun , Cui Jiangong , Xue Chenyang , Yan Shubin
Published: January 2017

A metal–insulator–metal (MIM) waveguide-coupled trapezoid cavity is presented, and the transmission properties are investigated by finite-element method. Results show that an asymmetric Fano profile emerged in the transmission spectrum, which was caused by the asymmetrical break of the MIM waveguide-coupled trapezoid cavity system. A refractive index sensitivity, Q-factor and FOM of approximately 750nm/RIU, 68.3 and 65.2 were measured based on the Fano resonance. The effect of the structural parameters on the transmission properties is also investigated. The results provide a new possibility for designing high-performance plasmonic devices.
Acetylation promotes TyrRS nuclear translocation to prevent oxidative damage
Authors: Cao Xuanye , Li Chaoqun , Xiao Siyu , Tang Yunlan , Huang Jing , Zhao Shuan , Li Xueyu , Li Jixi , Zhang Ruilin , Yu Wei
Published: January 2017

Significance

Aminoacyl-tRNA synthetases (AARSs) comprise a family of 20 enzymes that catalyze the first step of protein synthesis by esterifying specific amino acids to the 3′ ends of their cognate tRNAs. Protein acetylation, an evolutionarily conserved posttranslational modification, has recently been extensively investigated to regulate diverse cellular processes. This work provides the molecular evidence that one of the aminoacyl-tRNA synthetases is modulated by reversible acetylation. This study not only reveals a regulatory mechanism for the tRNA synthetase tyrosyl-tRNA synthetase (TyrRS) due to a posttranslational modification but also enriches knowledge of the regulatory pathway between p300/CBP-associated factor (PCAF)/sirtuin 1 (SIRT1) and the DNA damage/repair response.
Centuries of thermal sea-level rise due to anthropogenic emissions of short-lived greenhouse gases
Authors: Zickfeld Kirsten , Solomon Susan , Gilford Daniel M.
Published: January 2017

Significance

Human activities such as fossil-fuel burning have increased emissions of greenhouse gases (GHGs), which have warmed the Earth’s atmosphere and ocean and caused sea levels to rise. Some of these GHGs (e.g., methane) have atmospheric lifetimes of decades or less, whereas others (e.g., carbon dioxide) persist for centuries to millennia. As policy seeks to reduce climate changes, it is important to understand how mitigation of different gases each contributes to this goal. Our study shows that short-lived GHGs contribute to thermal expansion of the ocean over much longer time scales than their atmospheric lifetimes. Actions taken to reduce emissions of short-lived gases could mitigate centuries of additional future sea-level rise.
C-type lectin receptor DCIR modulates immunity to tuberculosis by sustaining type I interferon signaling in dendritic cells
Authors: Troegeler Anthony , Mercier Ingrid , Cougoule Céline , Pietretti Danilo , Colom André , Duval Carine , Vu Manh Thien-Phong , Capilla Florence , Poincloux Renaud , Pingris Karine , Nigou Jérôme , Rademann Jörg , Dalod Marc , Verreck Frank A. W. , Al Saati Talal , Lugo-Villarino Geanncarlo , Lepenies Bernd , Hudrisier Denis , Neyrolles Olivier
Published: January 2017

Significance

Tuberculosis (TB) is an immunopathology, mostly of the lung, due to an overexuberant immune response to the bacterial pathogenMycobacterium tuberculosis. Here, we demonstrate in vitro and in vivo that dendritic cell (DC) immunoreceptor (DCIR), a C-type lectin receptor expressed by DCs, modulates immunity to TB by sustaining type I IFN signaling in DCs. These findings were generalized beyond TB, in a model of in vivo antigen-presentation assay unrelated toM. tuberculosis, suggesting that they may extend to other pathologies, such as viral infections or autoimmune disorders. Thus, modulating DCIR activity may help to develop type I IFN-targeting therapies for a large repertoire of inflammatory disorders, including TB.
Steroid signaling in mature follicles is important for
Drosophila
ovulation
Authors: Knapp Elizabeth , Sun Jianjun
Published: January 2017

Significance

Ovulation is thought to be divergent from insects to mammals. In the latter case, ovulation is regulated by luteinizing hormone and the steroid hormone progesterone, neither of which is found in insects so far. This paper reports a role of ecdysteroids in
Drosophila
ovulation. Similar to the action of progesterone in mammals, 20-hydroxyecdysone produced in
Drosophila
follicle cells activates one of its receptors, EcR.B2, to allow proper activation of matrix metalloproteinase and follicle rupture. The conservation of steroid signaling in ovulation makes
Drosophila
a simple model to define the mechanism of steroid action in ovulation.
Crystal structure and mechanistic basis of a functional homolog of the antigen transporter TAP
Authors: Nöll Anne , Thomas Christoph , Herbring Valentina , Zollmann Tina , Barth Katja , Mehdipour Ahmad Reza , Tomasiak Thomas M. , Brüchert Stefan , Joseph Benesh , Abele Rupert , Oliéric Vincent , Wang Meitian , Diederichs Kay , Hummer Gerhard , Stroud Robert M. , Pos Klaas M. , Tampé Robert
Published: January 2017

Significance

ABC transporters shuttle chemically diverse substances across membranes in an energy-dependent manner. They mediate multidrug resistance in microorganisms and cancer cells and can cause human pathologies when dysfunctional. Although important insights into ABC transporters have been gained in recent years, fundamental questions concerning their mechanism remain open. Here, we identify the protein complex TmrAB as a functional homolog of the antigenic peptide transporter TAP and present its high-resolution structure. The structure adopts an asymmetric conformational state and is characterized by C-terminal zipper helices that are essential for efficient substrate translocation. The structure, together with functional studies, enables us to outline the general conformational dynamics of heterodimeric ABC transporters and to establish TmrAB as a model system for TAP.
Resistance to type 1 interferons is a major determinant of HIV-1 transmission fitness
Authors: Iyer Shilpa S. , Bibollet-Ruche Frederic , Sherrill-Mix Scott , Learn Gerald H. , Plenderleith Lindsey , Smith Andrew G. , Barbian Hannah J. , Russell Ronnie M. , Gondim Marcos V. P. , Bahari Catherine Y. , Shaw Christiana M. , Li Yingying , Decker Timothy , Haynes Barton F. , Shaw George M. , Sharp Paul M. , Borrow Persephone , Hahn Beatrice H.
Published: January 2017

Significance

Effective prevention strategies are urgently needed to control the spread of HIV-1. A critical barrier to developing such strategies is the lack of understanding of the host antiviral defenses that control HIV-1 replication in the mucosa at the site of entry. Here, we characterized viruses from matched donor and recipient pairs to determine whether transmitted HIV-1 strains exhibit traits that increase their transmission fitness. Characterizing 300 limiting dilution-derived isolates, we identified several properties that enhance virus replication in the face of a vigorous innate immune response, of which resistance to type 1 IFNs is the most important. These results provide new insights into the HIV-1 transmission process and define possible new targets for AIDS prevention and therapy.
Soluble klotho binds monosialoganglioside to regulate membrane microdomains and growth factor signaling
Authors: Dalton George , An Sung-Wan , Al-Juboori Saif I. , Nischan Nicole , Yoon Joonho , Dobrinskikh Evgenia , Hilgemann Donald W. , Xie Jian , Luby-Phelps Kate , Kohler Jennifer J. , Birnbaumer Lutz , Huang Chou-Long
Published: January 2017

Significance

Soluble klotho is the shed ectodomain of the antiaging membrane protein α-klotho that exhibits pleiotropic actions, including down-regulation of growth factor-driven PI3K signaling, contributing to lifespan prolongation, cardioprotection, and tumor inhibition. Whether membrane receptors exist for soluble klotho is unknown. We identify lipid rafts as receptors for soluble klotho. We show klotho binds specific sialic acid residues of gangliosides highly enriched in the outer leaflet of lipid rafts. Klotho binding to gangliosides modulates lipid organization and inhibits lipid raft-dependent PI3K signaling. In vivo, klotho-deficient mouse hearts have heightened raft-dependent PI3K signaling vs. wild-type hearts. We reveal a novel physiological regulator of lipid raft structure and function, and open new research to understand pleiotropic effects of klotho in cell signaling and metabolism.
Conformal tilings I: foundations, theory, and practice
Authors: Bowers Philip , Stephenson Kenneth
Published: January 2017

This paper opens a new chapter in the study of planar tilings by introducing conformal tilings. These are similar to traditional tilings in that they realize abstract patterns of combinatorial polygons as concrete patterns of geometric shapes, the tiles. In the conformal case, however, these geometric tiles carry prescribed conformal rather than prescribed euclidean structure. The authors develop the topic from the ground up: definitions and terminology, basic theory on existence, uniqueness and properties, numerous experiments and examples, comparisons to traditional tilings, patterns unique to conformal tiling, and details on computability through circle packing. Special attention is placed on aperiodic hierarchical tilings and on connections between abstract combinatorics on one hand and their geometric realizations on the other. Many of the motivations for studying tilings remain unchanged, not least being the pure beauty and intricacy of the patterns.
Facklamia Species as an Underrecognized Pathogen
Authors: Rahmati Elham , Martin Vanessa , Wong Darren , Sattler Fred , Petterson Jonas , Ward Pamela , Butler-Wu Susan M. , She Rosemary C.
Published: January 2017

Facklamia species are a rarely reported etiology of clinical infection with few cases described in literature. However, the prevalence of infection may be underestimated due to challenges in species identification. We describe 3 cases of Facklamia species bacteremia and the unique microbiologic aspects inherent to this genus that make it particularly challenging to identify. In addition, given the unique susceptibility profile of Facklamia species, we discuss the importance of fully identifying this organism when it is a suspected as a pathogen, to optimize therapy based on its distinct antibiotic resistance profile.
Relationship of Sacral Fractures to Nerve Injury: Is the Denis Classification Still Accurate?
Authors: Khan Jannat M. , Marquez-Lara Alejandro , Miller Anna N.
Published: January 2017

Objective:

Use modern computed tomographic imaging to reassess neurological injury risks associated with zone I–III sacral fractures as originally described by Denis et al.

Design:

Retrospective case–control study.

Setting:

University Level I Trauma Center.

Patients/Participants:

One thousand five hundred seven consecutive patients who presented with sacral fractures between January 2000 and August 2012.

Main Outcome Measurements:

Patients were stratified based on the diagnosis of acute neurological injury. The risk of severe and complex sacral fractures based on the presence of nerve injury was assessed.

Results:

The rate of nerve injury was significantly lower compared with historic data (3.5% vs. 21.6%,P< 0.001). Acute nerve injury was a significant risk factor for displaced (odds ratio [OR]: 8.4, 95% confidence interval [CI], 1.4–51.9) and comminuted (OR: 5.2, 95% CI, 1.7–16.3) sacral fractures as well as zone II (OR: 3.4, 95% CI, 1.1–10.1) and III (OR: 3.9, 95% CI, 1.0–16.4) fractures.

Conclusions:

The incidence of nerve injuries associated with sacral fractures is significantly lower than originally published by Denis et al. Patients with a nerve injury were highly correlated with having a displaced, comminuted, or zone III fracture, or spinopelvic dissociation; the authors recommend a fine cut computerized tomography for further investigation if these findings are not apparent on initial radiographic imaging.

Level of Evidence:

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.