bluuebunny/crossref_metadata_2025 huggingface dataset:
Outcomes of Craniofacial Open Surgery in Octogenarians
Authors: Ringel Barak , Carmel-Neiderman Narin , Ben-Ner Daniel , Pery Aviyah , Safadi Ahmad , Abergel Avraham , Margalit Nevo , Fliss Dan
Published: March 2018

Introduction The steady increase in average life expectancy has led to a rise in the number of referrals of elderly patients for major operations. It is not clear whether age itself is a risk factor for morbidity and mortality after skull base operations. We investigated a possible link among a cohort of patients older than 80 years of age who underwent those surgeries in our department.

Methods We conducted a retrospective analysis of all patients who underwent skull base surgery at the TASMC (Tel Aviv Sourasky Medical Center) between 2000 and 2016.

Results A total of 369 patients underwent open skull base surgeries in our institution, and 13 were patients older than 80 years. The median age of the octogenarians was 83.4 (range 80–89), and the male-to-female ratio was 7:6. Twelve patients had major systemic comorbidities. Four patients had major complications associated with surgery: three had early wound complications, and one each had early central nervous system complications, early and late systemic complications, and late orbital complications. This complication rate is comparable to that of our younger group of 356 patients. The overall survival rate was measured for 30 days, 1 year, and 3 years, and it was not significantly different between the octogenarians and that of the younger patients. Further comparison of the elderly group with 13 matched younger patients revealed no difference of morbidity and mortality between the two groups.

Conclusions Despite their systemic comorbidities, the morbidity and mortality rates associated with skull base surgery in octogenarians appear to be comparable to that of younger patients undergoing the same procedures.
Unusual Presentation of Childhood Reversible Angiopathy: Aphasia due to Acute Bilateral Paramedian Thalamic Infarct
Authors: Othman Makram , Massoud Leila , Kamoun Fatma , Triki Chahnez , Moalla Khadija
Published: March 2018

An 8-year-old right-handed girl manifested aphasia after bilateral thalamic infarcts. The features of thalamic aphasia are similar to that of previously reported patients with thalamic lesions. Paucity of speech, reduced voice volume, some paraphasia, and severe dysgraphia were present, but comprehension and repetition were preserved. Thalamic aphasia is usually associated with left thalamic lesions. Our patient also had spatial neglect and anosognosia probably due to right thalamic infarction. She had recovered near-normal speech after rehabilitation.
Similar Aquaporin9 and MAPK Expression Profiles in the Liver of Types 1 and 2 Diabetes Mellitus
Authors: Hou Jiaojiao , Li Yuan , Ren Xüxia , Gao Fei , Chen Yuqin , Yi Yaoxing , Kang Lili , Luo Yürui , Yang Mei
Published: March 2018

Aquaporin-9 (AQP9) is an aquaglyceroporin that biophysically conducts water, glycerol, and other small solutes. AQP9 is expressed in hepatocytes on the sinusoidal surfaces of hepatocyte plates in the liver, where it is considered responsible for the glycerol uptake in gluconeogenesis. However, limited information is available on the expression and regulating mechanism of AQP9 in different hyperglycemia models. Thus, this study examined the expression patterns of AQP9 and mitogen-activated protein kinase (MAPK) in Types 1 and 2 diabetes mellitus (DM) to clarify the roles and regulating mechanism of AQP9 in gluconeogenesis. Compared with the control group, the AQP9 expression significantly increased in both Types 1 and 2 DM, and the increased expression was associated with the activation of phosphorylated JNK (p-JNK) and the inhibition of phosphorylated p38 (p-p38). By contrast, phosphorylated ERK remained stable in the liver with Type 1 or 2 DM. These effects could be reversed by insulin treatment. That is, insulin downregulated AQP9 by inhibiting p-JNK and activating p-p38. The upregulation of AQP9 could be involved in gluconeogenesis and co-regulated by the JNK and p38 MAPK pathway in both Types 1 and 2 DM.
Leitlinie zur Diagnostik und Therapie von Patienten mit chronisch obstruktiver Bronchitis und Lungenemphysem (COPD)
Authors: Vogelmeier C. , Buhl R. , Burghuber O. , Criée C.-P. , Ewig S. , Godnic-Cvar J. , Hartl S. , Herth F. , Kardos P. , Kenn K. , Nowak D. , Rabe K. , Studnicka M. , Watz H. , Welte T. , Windisch W. , Worth H. ,   unter Mitwirkung der folgenden wissenschaftlichen Fachgesellschaften: Deutsche Gesellschaft für Arbeitsmedizin und Umweltmedizin e.V.,   Deutsche Gesellschaft für Rehabilitationswissenschaften e.V.
Published: March 2018

Das vorliegende Dokument ist eine Neufassung und Aktualisierung der Leitlinie zur Diagnostik und Therapie von Patienten mit COPD, die die bisherige Version aus dem Jahr 2007 ablöst. Die Fülle an neuen Erkenntnissen zu Risikofaktoren, Diagnostik, Schweregradeinschätzung, Prävention und medikamentösen sowie nicht medikamentösen Therapiemaßnahmen machten eine umfassende Überarbeitung erforderlich. Die neue Leitlinie baut auf das GOLD-Dokument unter Berücksichtigung von Besonderheiten in Deutschland und Österreich auf.
Effect of Vitamin K Supplementation on Glycemic Control: A Systematic Review and Meta-Analysis of Clinical Trials
Authors: Shahdadian Farnaz , Mohammadi Hamed , Rouhani Mohammad
Published: March 2018

Type 2 diabetes mellitus (T2DM) is one of the most important public health issues. Vitamin K supplementation might have favorable effect on risk factors of T2DM. The aim of this study was to perform a systematic review and meta-analysis of interventional studies to examine the effect of vitamin K supplementation on glycemic indices. A systematic search was performed in electronic databases including PubMed, Science Direct, ProQuest, Institute of Scientific Information Web of Science, and Google scholar up to July 2017. We used a random effects model to estimate pooled effect size of fasting blood sugar (FBS), 2-h oral glucose tolerance test (2-h OGTT), fasting insulin (FINS), and homeostasis model assessment-estimated insulin resistance (HOMA-IR). Five clinical trials (533 participants) fulfilled the eligibility criteria of the present meta-analysis. Overall, meta-analysis could not show any beneficial effect of vitamin K supplementation on FBS (–0.91 mg/dl, 95% CI: –2.57, 0.76, p=0.28), FINS (–0.35 μIU/ml, 95% CI: –1.70, 1.00, p=0.61), HOMA-IR (–0.06, 95% CI: –0.32, –0.19, p=0.63), and 2-h OGTT (–4.00 mg/dl, 95% CI: –20.00, 11.99, p=0.62). Sensitivity analysis showed that overall estimates were not affected by elimination of any study. We did not observe any evidence regarding publication bias. In conclusion, vitamin K supplementation had no signiﬁcant effect on glycemic control in healthy subjects. However, further studies should be performed on diabetic and pre-diabetic patients to determine the effect of vitamin K supplementation on impaired glycemic control.
Improvements to the ion Doppler spectrometer diagnostic on the HIT-SI experiments
Authors: Hossack Aaron , Chandra Rian , Everson Chris , Jarboe Tom
Published: March 2018

An ion Doppler spectrometer diagnostic system measuring impurity ion temperature and velocity on the HIT-SI and HIT-SI3 spheromak devices has been improved with higher spatiotemporal resolution and lower error than previously described devices. Hardware and software improvements to the established technique have resulted in a record of 6.9 μs temporal and ≤2.8 cm spatial resolution in the midplane of each device. These allow Ciii and Oii flow, displacement, and temperature profiles to be observed simultaneously. With 72 fused-silica fiber channels in two independent bundles, and an f/8.5 Czerny-Turner spectrometer coupled to a video camera, frame rates of up to ten times the imposed magnetic perturbation frequency of 14.5 kHz were achieved in HIT-SI, viewing the upper half of the midplane. In HIT-SI3, frame rates of up to eight times the perturbation frequency were achieved viewing both halves of the midplane. Biorthogonal decomposition is used as a novel filtering tool, reducing uncertainty in ion temperature from ≲13 to ≲5 eV (with an instrument temperature of 8-16 eV) and uncertainty in velocity from ≲2 to ≲1 km/s. Doppler shift and broadening are calculated via the Levenberg-Marquardt algorithm, after which the errors in velocity and temperature are uniquely specified. Axisymmetric temperature profiles on HIT-SI3 for Ciii peaked near the inboard current separatrix at ≈40 eV are observed. Axisymmetric plasma displacement profiles have been measured on HIT-SI3, peaking at ≈6 cm at the outboard separatrix. Both profiles agree with the upper half of the midplane observable by HIT-SI. With its complete midplane view, HIT-SI3 has unambiguously extracted axisymmetric, toroidal current dependent rotation of up to 3 km/s. Analysis of the temporal phase of the displacement uncovers a coherent structure, locked to the applied perturbation. Previously described diagnostic systems could not achieve such results.
Some new results for the one-loop mass correction to the compactified λϕ4 theory
Authors: Fucci Guglielmo , Kirsten Klaus
Published: March 2018

In this work, we consider the one-loop effective action of a self-interacting λϕ4 field propagating in a D dimensional Euclidean space endowed with d ≤ D compact dimensions. The main purpose of this paper is to compute the corrections to the mass of the field due to the presence of the compactified dimensions. Although the results of the one-loop correction to the mass of a λϕ4 field are very well known for compactified toroidal spaces, where the field obeys periodic boundary conditions, similar results do not appear to be readily available for cases in which the scalar field is subject to Dirichlet and Neumann boundary conditions. We apply the results of the one-loop mass correction to the study of the critical temperature in Ginzburg-Landau models.
Nonlinear saturation of the slab ITG instability and zonal flow generation with fully kinetic ions
Authors: Miecnikowski Matthew T. , Sturdevant Benjamin J. , Chen Yang , Parker Scott E.
Published: March 2018

Fully kinetic turbulence models are of interest for their potential to validate or replace gyrokinetic models in plasma regimes where the gyrokinetic expansion parameters are marginal. Here, we demonstrate fully kinetic ion capability by simulating the growth and nonlinear saturation of the ion-temperature-gradient instability in shearless slab geometry assuming adiabatic electrons and including zonal flow dynamics. The ion trajectories are integrated using the Lorentz force, and the cyclotron motion is fully resolved. Linear growth and nonlinear saturation characteristics show excellent agreement with analogous gyrokinetic simulations across a wide range of parameters. The fully kinetic simulation accurately reproduces the nonlinearly generated zonal flow. This work demonstrates nonlinear capability, resolution of weak gradient drive, and zonal flow physics, which are critical aspects of modeling plasma turbulence with full ion dynamics.
“Negative capacitance” in resistor-ferroelectric and ferroelectric-dielectric networks: Apparent or intrinsic?
Authors: Saha Atanu K. , Datta Suman , Gupta Sumeet K.
Published: March 2018

In this paper, we describe and analytically substantiate an alternate explanation for the negative capacitance (NC) effect in ferroelectrics (FE). We claim that the NC effect previously demonstrated in resistance-ferroelectric (R-FE) networks does not necessarily validate the existence of “S” shaped relation between polarization and voltage (according to Landau theory). In fact, the NC effect can be explained without invoking the “S”-shaped behavior of FE. We employ an analytical model for FE (Miller model) in which the steady state polarization strictly increases with the voltage across the FE and show that despite the inherent positive FE capacitance, reduction in FE voltage with the increase in its charge is possible in a R-FE network as well as in a ferroelectric-dielectric (FE-DE) stack. This can be attributed to a large increase in FE capacitance near the coercive voltage coupled with the polarization lag with respect to the electric field. Under certain conditions, these two factors yield transient NC effect. We analytically derive conditions for NC effect in R-FE and FE-DE networks. We couple our analysis with extensive simulations to explain the evolution of NC effect. We also compare the trends predicted by the aforementioned Miller model with Landau-Khalatnikov (L-K) model (static negative capacitance due to “S”-shape behaviour) and highlight the differences between the two approaches. First, with an increase in external resistance in the R-FE network, NC effect shows a non-monotonic behavior according to Miller model but increases according to L-K model. Second, with the increase in ramp-rate of applied voltage in the FE-DE stack, NC effect increases according to Miller model but decreases according to L-K model. These results unveil a possible way to experimentally validate the actual reason of NC effect in FE.
An intuitive two-fluid picture of spontaneous 2D collisionless magnetic reconnection and whistler wave generation
Authors: Yoon Young Dae , Bellan Paul M.
Published: March 2018

An intuitive and physical two-fluid picture of spontaneous 2D collisionless magnetic reconnection and whistler wave generation is presented in the framework of 3D electron-magnetohydrodynamics. In this regime, canonical circulation (Q=me∇×u+qeB) flux tubes can be defined in analogy to magnetic flux tubes in ideal magnetohydrodynamics. Following the 3D behavior of these Q flux tubes provides a new perspective on collisionless reconnection—a perspective that has been hard to perceive via examinations of 2D projections. This shows that even in a 2D geometry with an ignorable coordinate, a 3D examination is essential for a full comprehension of the process. Intuitive answers are given to three main questions in collisionless reconnection: why is reconnection spontaneous, why do particles accelerate extremely fast, and why are whistler waves generated? Possible extensions to other regimes are discussed.
Two-body Schrödinger wave functions in a plane-wave basis via separation of dimensions
Authors: Jerke Jonathan , Poirier Bill
Published: March 2018

Using a combination of ideas, the ground and several excited electronic states of the helium atom and the hydrogen molecule are computed to chemical accuracy—i.e., to within 1–2 mhartree or better. The basic strategy is very different from the standard electronic structure approach in that the full two-electron six-dimensional (6D) problem is tackled directly, rather than starting from a single-electron Hartree-Fock approximation. Electron correlation is thus treated exactly, even though computational requirements remain modest. The method also allows for exact wave functions to be computed, as well as energy levels. From the full-dimensional 6D wave functions computed here, radial distribution functions and radial correlation functions are extracted—as well as a 2D probability density function exhibiting antisymmetry for a single Cartesian component. These calculations support a more recent interpretation of Hund’s rule, which states that the lower energy of the higher spin-multiplicity states is actually due to reduced screening, rather than reduced electron-electron repulsion. Prospects for larger systems and/or electron dynamics applications appear promising.
Optimization of a high-yield, low-areal-density fusion product source at the National Ignition Facility with applications in nucleosynthesis experiments
Authors: Gatu Johnson M. , Casey D. T. , Hohenberger M. , Zylstra A. B. , Bacher A. , Brune C. R. , Bionta R. M. , Craxton R. S. , Ellison C. L. , Farrell M. , Frenje J. A. , Garbett W. , Garcia E. M. , Grim G. P. , Hartouni E. , Hatarik R. , Herrmann H. W. , Hohensee M. , Holunga D. M. , Hoppe M. , Jackson M. , Kabadi N. , Khan S. F. , Kilkenny J. D. , Kohut T. R. , Lahmann B. , Le H. P. , Li C. K. , Masse L. , McKenty P. W. , McNabb D. P. , Nikroo A. , Parham T. G. , Parker C. E. , Petrasso R. D. , Pino J. , Remington B. , Rice N. G. , Rinderknecht H. G. , Rosenberg M. J. , Sanchez J. , Sayre D. B. , Schoff M. E. , Shuldberg C. M. , Séguin F. H. , Sio H. , Walters Z. B. , Whitley H. D.
Published: March 2018

Polar-direct-drive exploding pushers are used as a high-yield, low-areal-density fusion product source at the National Ignition Facility with applications including diagnostic calibration, nuclear security, backlighting, electron-ion equilibration, and nucleosynthesis-relevant experiments. In this paper, two different paths to improving the performance of this platform are explored: (i) optimizing the laser drive, and (ii) optimizing the target. While the present study is specifically geared towards nucleosynthesis experiments, the results are generally applicable. Example data from T2/3He-gas-filled implosions with trace deuterium are used to show that yield and ion temperature (Tion) from 1.6 mm-outer-diameter thin-glass-shell capsule implosions are improved at a set laser energy by switching from a ramped to a square laser pulse shape, and that increased laser energy further improves yield and Tion, although by factors lower than predicted by 1 D simulations. Using data from D2/3He-gas-filled implosions, yield at a set Tion is experimentally verified to increase with capsule size. Uniform D3He-proton spectra from 3 mm-outer-diameter CH shell implosions demonstrate the utility of this platform for studying charged-particle-producing reactions relevant to stellar nucleosynthesis.
Transient chaos in the Lorenz-type map with periodic forcing
Authors: Maslennikov Oleg V. , Nekorkin Vladimir I. , Kurths Jürgen
Published: March 2018

We consider a case study of perturbing a system with a boundary crisis of a chaotic attractor by periodic forcing. In the static case, the system exhibits persistent chaos below the critical value of the control parameter but transient chaos above the critical value. We discuss what happens to the system and particularly to the transient chaotic dynamics if the control parameter periodically oscillates. We find a non-exponential decaying behavior of the survival probability function, study the impact of the forcing frequency and amplitude on the escape rate, analyze the phase-space image of the observed dynamics, and investigate the influence of initial conditions.
Theoretical investigation of the structural, electronic, and thermodynamic properties of CdS1-xSex alloys
Authors: Long Debing , Li Mingkai , Meng Dongxue , Ahuja Rajeev , He Yunbin
Published: March 2018

In this work, the structural, electronic, and thermodynamic properties of wurtzite (WZ) and zincblende (ZB) CdS1-xSex alloys are investigated using the density functional theory (DFT) and the cluster expansion method. A special quasirandom structure containing 16 atoms is constructed to calculate the band structures of random alloys. The band gaps of CdS1-xSex alloys are direct and decrease as the Se content increases. The delta self-consistent-field method is applied to correct band gaps that are underestimated by DFT. The band offsets clearly reflect the variation in valence band maxima and conduction band minima, thus providing information useful to the design of relevant quantum well structures. The positive formation enthalpies of both phases imply that CdS1-xSex is an immiscible system and tends to phase separate. The influence of lattice vibrations on the phase diagram is investigated by calculating the phonon density of states. Lattice vibration effects can reduce the critical temperature Tc and increase alloy solid solubilities. This influence is especially significant in the ZB structure. When only chemical interactions are present, the Tc values for WZ- and ZB-CdS1-xSex are 260 K and 249 K, respectively. The lattice vibration enthalpy and entropy lower the Tc to 255 K and 233 K, respectively.
High quality Al2O3/(100) oxygen-terminated diamond interface for MOSFETs fabrication
Authors: Pham T. T. , Gutiérrez M. , Masante C. , Rouger N. , Eon D. , Gheeraert E. , Araùjo D. , Pernot J.
Published: March 2018

In this letter, we report on the improvement of gate controlled Al2O3/(100) boron doped (B-doped) oxygen-terminated diamond (O-diamond) Metal Oxide Semiconductor Capacitors using 40 nm thick Al2O3 deposited by Atomic Layer Deposition at 380 °C and then annealed at 500 °C in vacuum conditions. The high quality of Al2O3 and an Al2O3/diamond interface is verified thanks to electrical measurements and Transmission Electron Microscopy (TEM) measurements. A density of interface states lower than 1012 eV−1 cm−2 is measured from the flat-band regime to the depletion regime. The shift of the flat-band voltage and the leakage current through the oxide are significantly reduced in good agreement with the mono-crystalline character of the Al2O3 layer revealed by TEM.
Interaction of a shock wave with multiple spheres suspended in different arrangements
Authors: Zhang Li-Te , Sui Zhen-Zhen , Shi Hong-Hui
Published: March 2018

In this study, the unsteady drag force, Fd, drag coefficient, Cd, and the relevant dynamic behaviors of waves caused by the interaction between a planar incident shock wave and a multi-sphere model are investigated by using imbedded accelerometers and a high-speed Schlieren system. The shock wave is produced in a horizontal 200 mm inner diameter circular shock tube with a 2000 mm × 200 mm × 200 mm transparent test section. The time history of Cd is obtained based on band-block and low-pass Fast Fourier Transformation filtering combined with Savitzky-Golay polynomial smoothing for the measured acceleration. The effects of shock Mach number, Ms, geometry of multi-sphere model, nondimensional distance between sphere centers, H, and channel blockage are analyzed. We find that all time histories of Cd have a similar double-peak shaped main structure. It is due to wave reflection, diffraction, interference, and convergence at different positions of the spheres. The peak Fd increases, whereas the peak Cd decreases monotonically with increasing Ms. The increase of shock strength due to shock focusing by upstream spheres increases the peak Fd of downstream spheres. Both the increase in sphere number and the decrease in distance between spheres promote wave interference between neighboring spheres. As long as the wave interference times are shorter than the peak times, the peak Fd and Cd are higher compared to a single sphere.
Equations of state for the fully flexible WCA chains in the fluid and solid phases based on Wertheims-TPT2
Authors: Mirzaeinia Ali , Feyzi Farzaneh , Hashemianzadeh Seyed Majid
Published: March 2018

Based on Wertheim’s second order thermodynamic perturbation theory (TPT2), equations of state (EOSs) are presented for the fluid and solid phases of tangent, freely jointed spheres. It is considered that the spheres interact with each other through the Weeks-Chandler-Anderson (WCA) potential. The developed TPT2 EOS is the sum of a monomeric reference term and a perturbation contribution due to bonding. MC NVT simulations are performed to determine the structural properties of the reference system in the reduced temperature range of 0.6 ≤ T* ≤ 4.0 and the packing fraction range of 0.1 ≤ η ≤ 0.72. Mathematical functions are fitted to the simulation results of the reference system and employed in the framework of Wertheim’s theory to develop TPT2 EOSs for the fluid and solid phases. The extended EOSs are compared to the MC NPT simulation results of the compressibility factor and internal energy of the fully flexible chain systems. Simulations are performed for the WCA chain system for chain lengths of up to 15 at T* = 1.0, 1.5, 2.0, 3.0. Across all the reduced temperatures, the agreement between the results of the TPT2 EOS and MC simulations is remarkable. Overall Average Absolute Relative Percent Deviation at T* = 1.0 for the compressibility factor in the entire chain lengths we covered is 0.51 and 0.77 for the solid and fluid phases, respectively. Similar features are observed in the case of residual internal energy.
Bulk dynamics of Brownian hard disks: Dynamical density functional theory versus experiments on two-dimensional colloidal hard spheres
Authors: Stopper Daniel , Thorneywork Alice L. , Dullens Roel P. A. , Roth Roland
Published: March 2018

Using dynamical density functional theory (DDFT), we theoretically study Brownian self-diffusion and structural relaxation of hard disks and compare to experimental results on quasi two-dimensional colloidal hard spheres. To this end, we calculate the self-van Hove correlation function and distinct van Hove correlation function by extending a recently proposed DDFT-approach for three-dimensional systems to two dimensions. We find that the theoretical results for both self-part and distinct part of the van Hove function are in very good quantitative agreement with the experiments up to relatively high fluid packing fractions of roughly 0.60. However, at even higher densities, deviations between the experiment and the theoretical approach become clearly visible. Upon increasing packing fraction, in experiments, the short-time self-diffusive behavior is strongly affected by hydrodynamic effects and leads to a significant decrease in the respective mean-squared displacement. By contrast, and in accordance with previous simulation studies, the present DDFT, which neglects hydrodynamic effects, shows no dependence on the particle density for this quantity.
Zonal structure effect on the nonlinear saturation of reverse shear Alfven eigenmodes
Authors: Chen Y. , Fu G. Y. , Collins C. , Taimourzadeh S. , Parker S. E.
Published: March 2018

A gyrokinetic ion/fluid electron hybrid model is used to study the nonlinear evolution of reverse shear Alfven eigenmodes (RSAE) driven by energetic particles. When only the energetic particle nonlinear effects are included, the saturation amplitude of a single-n RSAE follows the trapping scaling, δB/B∼(γ/ω)2. When the nonlinear effects of thermal ions and electrons are included, zonal structures are force generated but do not affect the saturation amplitude for γ/ω≤0.03. No spontaneous generation of zonal structures is observed, in contrast to ion-temperature-gradient-driven modes. At larger energetic particle drive, the effects of zonal structures cause a significant reduction in the RSAE saturation amplitude. The reduction is not caused by the zonal flow shearing of the RSAE, but by the force-generated n = 0 component in the thermal ion distribution function and the electron density. These n = 0 perturbations lead to nonlinear evolution of the RSAE mode structure and enhance damping.
Asymmetric and partial injection locking of a three-terminal spin-torque oscillator
Authors: Jué Emilie , Pufall Matthew R. , Rippard William H.
Published: March 2018

We measure the injection locking of a three-terminal spin-torque oscillator (STO) excited by spin-orbit torque. The device consists of a magnetic tunnel junction on top of a Pt wire. A DC and an AC current are applied through the Pt wire to induce the oscillations and injection lock the STO, respectively. The injection locking is studied at fMW ≈ f0 or at fMW ≈ 2f0, where fMW is the microwave frequency and f0 is the free running frequency of the STO. The frequency response is qualitatively different from the injection locking in STOs generally reported experimentally and theoretically. Whereas typical phase-locking behavior is observed at fMW ≈ 2f0, the injection locking at fMW ≈ f0 is only partial and exhibits a strongly asymmetric frequency response. Defining the frequency deviation range as the frequency range where the STO differs from its free running frequency, we show that the asymmetric interaction is characterized by a pulling effect present on only one side of the frequency deviation range, the presence of a sideband inside the frequency deviation range, and an interaction of the STO with the microwave current that is wider than the frequency deviation range.
Rubidium distribution at atomic scale in high efficient Cu(In,Ga)Se2 thin-film solar cells
Authors: Vilalta-Clemente Arantxa , Raghuwanshi Mohit , Duguay Sébastien , Castro Celia , Cadel Emmanuel , Pareige Philippe , Jackson Philip , Wuerz Roland , Hariskos Dimitrios , Witte Wolfram
Published: March 2018

The introduction of a rubidium fluoride post deposition treatment (RbF-PDT) for Cu(In,Ga)Se2 (CIGS) absorber layers has led to a record efficiency up to 22.6% for thin-film solar cell technology. In the present work, high efficiency CIGS samples with RbF-PDT have been investigated by atom probe tomography (APT) to reveal the atomic distribution of all alkali elements present in CIGS layers and compared with non-treated samples. A Scanning Electron Microscopy Dual beam station (Focused Ion Beam–Gas Injection System) as well as Transmission Kikuchi diffraction is used for atom probe sample preparation and localization of the grain boundaries (GBs) in the area of interest. The analysis of the 3D atomic scale APT reconstructions of CIGS samples with RbF-PDT shows that inside grains, Rb is under the detection limit, but the Na concentration is enhanced as compared to the reference sample without Rb. At the GBs, a high concentration of Rb reaching 1.5 at. % was found, and Na and K (diffusing from the glass substrate) are also segregated at GBs but at lower concentrations as compared to Rb. The intentional introduction of Rb leads to significant changes in the chemical composition of CIGS matrix and at GBs, which might contribute to improve device efficiency.
Role of quantum-confined stark effect on bias dependent photoluminescence of N-polar GaN/InGaN multi-quantum disk amber light emitting diodes
Authors: Tangi Malleswararao , Mishra Pawan , Janjua Bilal , Prabaswara Aditya , Zhao Chao , Priante Davide , Min Jung-Wook , Ng Tien Khee , Ooi Boon S.
Published: March 2018

We study the impact of quantum-confined stark effect (QCSE) on bias dependent micro-photoluminescence emission of the quantum disk (Q-disk) based nanowires light emitting diodes (NWs-LED) exhibiting the amber colored emission. The NWs are found to be nitrogen polar (N-polar) verified using KOH wet chemical etching and valence band spectrum analysis of high-resolution X-ray photoelectron spectroscopy. The crystal structure and quality of the NWs were investigated by high-angle annular dark field - scanning transmission electron microscopy. The LEDs were fabricated to acquire the bias dependent micro-photoluminescence spectra. We observe a redshift and a blueshift of the μPL peak in the forward and reverse bias conditions, respectively, with reference to zero bias, which is in contrast to the metal-polar InGaN well-based LEDs in the literature. Such opposite shifts of μPL peak emission observed for N-polar NWs-LEDs, in our study, are due to the change in the direction of the internal piezoelectric field. The quenching of PL intensity, under the reverse bias conditions, is ascribed to the reduction of electron-hole overlap. Furthermore, the blueshift of μPL emission with increasing excitation power reveals the suppression of QCSE resulting from the photo-generated carriers. Thereby, our study confirms the presence of QCSE for NWs-LEDs from both bias and power dependent μPL measurements. Thus, this study serves to understand the QCSE in N-polar InGaN Q-disk NWs-LEDs and other related wide-bandgap nitride nanowires, in general.
A novel numerical scheme for nonlinear electron plasma oscillations
Authors: Verma Prabal Singh
Published: March 2018

In this work, we suggest an easy-to-code higher-order finite volume semi-discrete scheme to analyze the nonlinear behavior of the electron-plasma oscillations by the direct numerical simulation of electron fluid equations. The present method employs a fourth-order accurate centrally weighted essentially nonoscillatory reconstruction polynomial for estimating the numerical flux at the grid-cell interfaces, and a fourth-order Runge-Kutta method for the time integration. The numerical implementation is validated by reproducing earlier results for both non-dissipative and dissipative cold plasmas. The stability of the present scheme is illustrated by evolving the nonlinear electron plasma oscillations in a cold non-dissipative plasma for hundred plasma periods, which also display a negligible numerical dissipation. Moreover, the fourth-order accuracy of the existing approach is confirmed by evaluating the convergence of errors for nonlinear electron plasma oscillations in a cold non-dissipative plasma.
Stochastically pumped adaptation and directional motion of molecular machines
Authors: Astumian R. Dean
Published: March 2018

Recent developments in synthetic molecular motors and pumps have sprung from a remarkable confluence of experiment and theory. Synthetic accomplishments have facilitated the ability to design and create molecules, many of them featuring mechanically bonded components, to carry out specific functions in their environment—walking along a polymeric track, unidirectional circling of one ring about another, synthesizing stereoisomers according to an external protocol, or pumping rings onto a long rod-like molecule to form and maintain high-energy, complex, nonequilibrium structures from simpler antecedents. Progress in the theory of nanoscale stochastic thermodynamics, specifically the generalization and extension of the principle of microscopic reversibility to the single-molecule regime, has enhanced the understanding of the design requirements for achieving strong unidirectional motion and high efficiency of these synthetic molecular machines for harnessing energy from external fluctuations to carry out mechanical and/or chemical functions in their environment. A key insight is that the interaction between the fluctuations and the transition state energies plays a central role in determining the steady-state concentrations. Kinetic asymmetry, a requirement for stochastic adaptation, occurs when there is an imbalance in the effect of the fluctuations on the forward and reverse rate constants. Because of strong viscosity, the motions of the machine can be viewed as mechanical equilibrium processes where mechanical resonances are simply impossible but where the probability distributions for the state occupancies and trajectories are very different from those that would be expected at thermodynamic equilibrium.
Structure and mechanism of the deformation of Grade 2 titanium in plastometric studies
Authors: Bańczerowski Jakub , Jeleńkowski Jerzy , Skalski Konstanty , Sawicki Sylwester , Wachowski Marcin
Published: March 2018

In this paper, the results of plastometric and material studies on grade 2 titanium are presented. Cylindrical titanium samples were compressed at elevated temperatures on a Gleeble thermo-mechanical simulator. The process was captured in the form of stress-strain diagrams. Then, for the chosen-deformed samples, structural studies were performed on a digital light microscope. On the basis of the results, it was possible to determine the plastometric processing conditions that are most suitable for the fragmentation of the grains of the tested titanium. In order to find optimal processing parameters, it was also important to describe the plastometric process through the appropriate constitutive equations. Material constants in this equation were determined on the basis of a hyperbolic sinusoidal equation.

This paper is part of a thematic issue on Titanium.
Damping performance of YSZ coating prepared by different EB-PVD parameters
Authors: Du Guangyu , Li Zhuolong , Tan Zhen , Li Guohao , Lin Zeng , Ba Dechun
Published: March 2018

A yttrium-stabilised zirconia (YSZ) coating was prepared on Ti–6Al–4 substrates by electron beam physical vapour deposition (EB-PVD). The effect of substrate temperature and beam intensity on the microstructure of the coating was researched. Damping characteristics of the coatings under different processing parameters were compared. The microstructure and crystal structure were determined with scanning electron microscope (SEM) and X-Ray Diffraction (XRD), respectively. The damping properties of the coating were measured by dynamic mechanical analyzer (DMA). The decrease in the substrate temperature leads to diminution of the grain size of coating, which increases the loss factor ( Q−1). The crystal defects and micro-cracks of the coating are also the main reasons for the improvement of the damping performance.
Establishment of plasmid vector and allelic exchange mutagenesis systems in a mycobacterial strain that is able to degrade polycyclic aromatic hydrocarbon
Authors: Kishida Kouhei , Ogawa Natsumi , Ichihashi Eikichi , Kato Hiromi , Nagata Yuji , Ohtsubo Yoshiyuki , Tsuda Masataka
Published: March 2018

Plasmid vector and allelic exchange mutagenesis systems were established for the genetic analysis of a phenanthrene-degrading mycobacterial strain, Mycobacterium sp. EPa45. Successful application of these systems revealed the necessity of the EPa45 phdI gene for the degradation of 1-hydroxy-2-naphthoate, which has been proposed to be an intermediate product in the degradation pathway of phenanthrene.
Signaling function of PRC2 is essential for TCR-driven T cell responses
Authors: Dobenecker Marc-Werner , Park Joon Seok , Marcello Jonas , McCabe Michael T. , Gregory Richard , Knight Steven D. , Rioja Inmaculada , Bassil Anna K. , Prinjha Rabinder K. , Tarakhovsky Alexander
Published: March 2018

Differentiation and activation of T cells require the activity of numerous histone lysine methyltransferases (HMT) that control the transcriptional T cell output. One of the most potent regulators of T cell differentiation is the HMT Ezh2. Ezh2 is a key enzymatic component of polycomb repressive complex 2 (PRC2), which silences gene expression by histone H3 di/tri-methylation at lysine 27. Surprisingly, in many cell types, including T cells, Ezh2 is localized in both the nucleus and the cytosol. Here we show the presence of a nuclear-like PRC2 complex in T cell cytosol and demonstrate a role of cytosolic PRC2 in T cell antigen receptor (TCR)–mediated signaling. We show that short-term suppression of PRC2 precludes TCR-driven T cell activation in vitro. We also demonstrate that pharmacological inhibition of PRC2 in vivo greatly attenuates the severe T cell–driven autoimmunity caused by regulatory T cell depletion. Our data reveal cytoplasmic PRC2 is one of the most potent regulators of T cell activation and point toward the therapeutic potential of PRC2 inhibitors for the treatment of T cell–driven autoimmune diseases.
The Pivot Point between Problem Presentation and Advice in a Health Helpline Service
Authors: Bloch Steven , Antaki Charles
Published: March 2018

This article examines interactions between callers to a health helpline and specialist nurses. Helpline call-takers must judge the appropriate moment to move from listening to the caller's problem to offering them the appropriate service. In a study of Parkinson's UK nurse call-takers, we find that the pivot is the point at which the caller reports the upshot of their trouble in terms of an impact on their daily life. Indeed, if the caller seems likely not to produce this upshot report, it is generated by the call-taker. Using the method of conversation analysis, we analyse how these upshot formulations are reached, and how the call-taker subsequently edits them to deliver a service that stays within their institutional guidelines. The findings contribute to sociological and clinical understandings about how health problems are framed and managed interactionally to reach a deliverable outcome for both participants in a helpline environment.
Disruptive sexual selection on male body size in the polyphenic black scavenger fly Sepsis thoracica
Authors: Busso Juan Pablo , Blanckenhorn Wolf U
Published: March 2018

Sexual selection has 2 main components, female preference and male–male competition, which can lead males to adopt alternative reproductive tactics to optimize their reproductive success. Two traits that significantly influence reproductive success are body size and coloration, as they can facilitate access to females through male contests or as female attractors. We investigated whether, and if so which mechanism of sexual selection contributes to the maintenance, and possibly even the establishment, of 2 almost discrete male morphs in the polyphenic black scavenger fly Sepsis thoracica (Diptera: Sepsidae): small and black, or large and amber. We performed 2 complementary laboratory experiments to evaluate the mating success of the different male morphs and the behaviors (of both males and females) presumably mediating their mating success. We found evidence for intraspecific disruptive sexual selection on male body size that is mediated by male–male interactions, and significant positive directional selection on body size that interacted with (directional) selection on coloration, likely contributing to the origin and/or maintenance of the threshold relationship between the 2 traits in this species. The simultaneous occurrence of disruptive selection and polyphenism in S. thoracica supports the role of sexual selection in the intraspecific diversification of coupled traits (here body size and coloration), which could be a speciation starting point.
Acetaminophen as a Renoprotective Adjunctive Treatment in Patients With Severe and Moderately Severe Falciparum Malaria: A Randomized, Controlled, Open-Label Trial
Authors: Plewes Katherine , Kingston Hugh W F , Ghose Aniruddha , Wattanakul Thanaporn , Hassan Md Mahtab Uddin , Haider Md Shafiul , Dutta Prodip K , Islam Md Akhterul , Alam Shamsul , Jahangir Selim Md , Zahed A S M , Sattar Md Abdus , Chowdhury M A Hassan , Herdman M Trent , Leopold Stije J , Ishioka Haruhiko , Piera Kim A , Charunwatthana Prakaykaew , Silamut Kamolrat , Yeo Tsin W , Lee Sue J , Mukaka Mavuto , Maude Richard J , Turner Gareth D H , Faiz Md Abul , Tarning Joel , Oates John A , Anstey Nicholas M , White Nicholas J , Day Nicholas P J , Hossain Md Amir , Roberts II L Jackson , Dondorp Arjen M
Published: March 2018

This randomized, controlled trial shows that acetaminophen reduces kidney dysfunction and risk of developing acute kidney injury, particularly in severe malaria patients who present with high plasma hemoglobin, supporting the hypothesis that acetaminophen inhibits cell-free hemoglobin-mediated renal tubular oxidative damage.
A Wake-up Call for Human Immunodeficiency Virus (HIV) Providers: Obstructive Sleep Apnea in People Living With HIV
Authors: Owens Robert L , Hicks Charles B
Published: March 2018

Obstructive sleep apnea (OSA) is defined by repetitive collapse of the upper airway during sleep leading to transient hypoxemia and arousals from sleep. Surges in sympathetic activity, repeated oxygen desaturation, and sleep fragmentation can lead to cardiovascular (eg, myocardial infarction) and neurocognitive (eg, excessive daytime sleepiness) consequences. Emerging data suggest that OSA is common in people living with human immunodeficiency virus (PLWH) and that traditional risk factors for OSA, such as obesity, are not highly predictive of OSA in PLWH. Untreated OSA is associated with increased fatigue and levels of inflammation. Despite these data, most PLWH with OSA remain undiagnosed and untreated. Improved awareness of OSA among healthcare providers and greater use of OSA diagnostic approaches have the potential to substantially improve quality of life and outcomes in PLWH.
Featured Article: Interpersonal Stressors and Resources as Predictors of Adolescent Adjustment Following Traumatic Brain Injury
Authors: Lantagne Ann , Peterson Robin L , Kirkwood Michael W , Taylor H Gerry , Stancin Terry , Yeates Keith Owen , Wade Shari L
Published: March 2018

Objective

The present study sought to examine adolescents’ perceptions of their interpersonal stressors and resources across parent, sibling, friend, and school relationships, and the longitudinal associations with self-reported adjustment after traumatic brain injury (TBI) over a 12-month period.

Methods

We examined the main effects of stressors and resources on internalizing and externalizing symptoms in 152 adolescents who had sustained complicated mild-to-severe TBI. We also investigated the conjoint effects of stressors and resources and the moderating effects of TBI severity with stressors and resources on outcomes.

Results

High stressors consistently predicted worse adjustment. High resources were generally only associated with fewer internalizing symptoms. Main effects were qualified by interactions between school stressors and resources in predicting externalizing symptoms and between friend stressors and resources in predicting internalizing and externalizing symptoms. For school stressors, the effects of resources on externalizing symptoms functioned as a buffer. In comparison, the buffering effects of friend resources on internalizing and externalizing symptoms disappeared at moderate-to-high levels of friend stress. Moderating effects of TBI severity were also observed, such that as family resources increased, only adolescents with complicated mild-to-moderate TBI, but not those with severe TBI, experienced decreases in internalizing and eternalizing symptoms.

Conclusion

Interpersonal stressors and social support have important implications for adolescent adjustment after TBI. Adolescents with low levels of school resources, with high levels of friend stress, and who sustain severe TBI are at greatest risk for difficulties with adjustment.
Military Preventive Medicine and Medical Surveillance in the Post-Cold War Era
Authors: Brundage John F.
Published: March 2018

In response to the end of the cold war, the United States developed new foreign policy and national security strategies. As a result, many medical support concepts that were operative during the cold war were invalidated. Recently, the Chairman of the Joint Chiefs of Staff provided direction and guidance for long-range strategic planning (Joint Vision 2010). Medical support doctrine that is being developed within the framework of Joint Vision 2010 relies on currently unavailable preventive medicine and medical surveillance capabilities. This report analyzes the relevance and roles of military preventive medicine and medical surveillance in the context of post-cold war resource constraints and military medical support needs, presents the rationale for and objectives of a demand-reduction medical support strategy, and outlines the roles, responsibilities, and characteristics of a defense medical surveillance system.
Use of Medical Specialties in Medical Operations other than War: Lessons from Saudi Arabia
Authors: Newmark Jonathan , France Larry O.
Published: March 2018

From the experience of a U.S. Army Air Defense Artillery “battalion-plus” task force serving a 6-month rotation in the Kingdom of Saudi Arabia, we compiled the requirements for specialty consultations on deployed personnel in the predeployment screening phase, during deployment (including both inpatient hospitalizations and medical evacuations), and immediately upon return to home station. We required a wide variety of specialty expertise. In every phase of the operation, we consulted orthopedic surgery most often. Nonsurgical and surgical specialists were consulted in roughly equal numbers. Almost every field of adult medicine was represented in our sample. The distribution of consultations across specialties differs from what would be expected in combat but is similar to that seen in the few other studies of comparable populations. Excellent host nation support allowed us to use specialty expertise to an almost ideal extent. These data represent the most complete “snapshot” that has been taken of the requirements for specialty medical consultations in a military operation other than war (MOOTW). They demonstrate that under MOOTW conditions, even a healthy Army population requires the assistance of a full panel of medical specialties. They should serve as a benchmark for planners estimating the medical specialty needs that the Army must provide. Military medicine must provide access to essentially all medical specialties for personnel deployed under MOOTW conditions, whether through host nation support, telemedicine, or medical evacuation.