bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical investigation of the interaction between a planar shock wave with square and triangular bubbles containing different gases
Authors: Igra Dan , Igra Ozer
Published: May 2018

The interaction between a planar shock wave and square and triangular bubbles containing either SF6, He, Ar, or CO2 is studied numerically. It is shown that, due to the existing large differences in the molecular weight, the specific heat ratio, and the acoustic impedance between these gases, different wave patterns and pressure distribution inside the bubbles are developed during the interaction process. In the case of heavy gases, the velocity of the shock wave propagating along the bubble inner surface is always less than that of the incident shock wave and higher than that of the transmitted shock wave. However, in the case of the light gas (He), the fastest one is the transmitted shock wave and the slowest one is the incident shock wave. The largest pressure jump is witnessed in the SF6 case, while the smallest pressure jump is seen in the helium case. There are also pronounced differences in the deformation of the investigated bubbles; while triangular bubbles filled with either Ar, CO2, or SF6 were deformed to a crescent shape, the helium bubble is deformed to a trapezoidal shape with three pairs of vortices emanating from its surface.
Room temperature ferromagnetism in BiFe1−xMnxO3 thin film induced by spin-structure manipulation
Authors: Shigematsu Kei , Asakura Takeshi , Yamamoto Hajime , Shimizu Keisuke , Katsumata Marin , Shimizu Haruki , Sakai Yuki , Hojo Hajime , Mibu Ko , Azuma Masaki
Published: May 2018

The evolution of crystal structure, spin structure, and macroscopic magnetization of manganese-substituted BiFeO3 (BiFe1−xMnxO3), a candidate for multiferroic materials, were investigated on bulk and epitaxial thin-film. Mn substitution for Fe induced collinear antiferromagnetic spin structure around room temperature by destabilizing the cycloidal spin modulation which prohibited the appearance of net magnetization generated by Dzyaloshinskii-Moriya interaction. For the bulk samples, however, no significant signal of ferromagnetism was observed because the direction of the ordered spins was close to parallel to the electric polarization so that spin-canting did not occur. On the contrary, BiFe1−xMnxO3 thin film on SrTiO3 (001) had a collinear spin structure with the spin direction perpendicular to the electric polarization at room temperature, where the appearance of spontaneous magnetization was expected. Indeed, ferromagnetic hysteresis behavior was observed for BiFe0.9Mn0.1O3 thin film.
Input signal shaping based on harmonic frequency response function for suppressing nonlinear optical frequency in frequency-scanning interferometry
Authors: Zhu Yu , Liu Zhigang , Deng Wen , Deng Zhongwen
Published: May 2018

Frequency-scanning interferometry (FSI) using an external cavity diode laser (ECDL) is essential for many applications of the absolute distance measurement. However, owing to the hysteresis and creep of the piezoelectric actuator inherent in the ECDL, the optical frequency scanning exhibits a nonlinearity that seriously affects the phase extraction accuracy of the interference signal and results in the reduction of the measurement accuracy. To suppress the optical frequency nonlinearity, a harmonic frequency synthesis method for shaping the desired input signal instead of the original triangular wave is presented. The effectiveness of the presented shaping method is demonstrated through the comparison of the experimental results. Compared with an incremental Renishaw interferometer, the standard deviation of the displacement measurement of the FSI system is less than 2.4 μm when driven by the shaped signal.
Three-dimensional particle-particle simulations: Dependence of relaxation time on plasma parameter
Authors: Zhao Yinjian
Published: May 2018

A particle-particle simulation model is applied to investigate the dependence of the relaxation time on the plasma parameter in a three-dimensional unmagnetized plasma. It is found that the relaxation time increases linearly as the plasma parameter increases within the range of the plasma parameter from 2 to 10; when the plasma parameter equals 2, the relaxation time is independent of the total number of particles, but when the plasma parameter equals 10, the relaxation time slightly increases as the total number of particles increases, which indicates the transition of a plasma from collisional to collisionless. In addition, ions with initial Maxwell-Boltzmann (MB) distribution are found to stay in the MB distribution during the whole simulation time, and the mass of ions does not significantly affect the relaxation time of electrons. This work also shows the feasibility of the particle-particle model when using GPU parallel computing techniques.
Two mechanisms of resonance overlapping in excitation of azimuthal surface waves by rotating relativistic electron beams
Authors: Girka Igor O. , Pavlenko Ivan V. , Thumm Manfred
Published: May 2018

Azimuthal surface waves are electromagnetic eigenwaves of cylindrical plasma-filled metallic waveguides with a stationary axial magnetic field. These waves with extraordinary polarization can effectively interact with relativistic electron beams rotating along large Larmor orbits in the gap, which separates the plasma column from the waveguide wall. Both widening the layer and increasing the beam particle density are demonstrated to cause resonance overlapping seen from the perspective of the growth rate dependence on the effective wave number.
Multi-directional emission and detection of spin waves propagating in yttrium iron garnet with wavelengths down to about 100 nm
Authors: Maendl Stefan , Grundler Dirk
Published: May 2018

We performed broadband spin-wave spectroscopy on 200 nm thick yttrium iron garnet containing arrays of partially embedded magnetic nanodisks. Using integrated coplanar waveguides (CPWs), we studied the excitation and transmission of spin waves depending on the presence of nanomagnet arrays of different lateral extensions. By means of the grating coupler effect, we excited spin waves propagating in multiple lateral directions with wavelengths down to 111 nm. They exhibited group velocities of up to 1 km/s. Detection of such short-wavelength spin waves was possible only in symmetrically designed emitter/detector configurations, not with a bare CPW. We report spin waves propagating between grating couplers under oblique angles exhibiting a wave vector component parallel to the CPW. The effective propagation distance amounted to about 80 μm. Such transmission signals were not addressed before and substantiate the versatility of the grating coupler effect for implementing nanomagnonic circuits.
Autoignition of hydrogen in shear flows
Authors: Kalbhor Abhijit , Chaudhuri Swetaprovo , Chitilappilly Lazar
Published: May 2018

In this paper, we compare the autoignition characteristics of laminar, nitrogen-diluted hydrogen jets in two different oxidizer flow configurations: (a) co-flowing heated air and (b) wake of heated air, using two-dimensional numerical simulations coupled with detailed chemical kinetics. In both cases, autoignition is observed to initiate at locations with low scalar dissipation rates and high HO2 depletion rates. It is found that the induction stage prior to autoignition is primarily dominated by chemical kinetics and diffusion while the improved scalar mixing imparted by the large-scale flow structures controls the ignition progress in later stages. We further investigate the ignition transience and its connection with mixing by varying the initial wake conditions and fuel jet to oxidizer velocity ratios. These studies reveal that the autoignition delay times are independent of initial wake flow conditions. However, with increased jet velocity ratios, the later stages of ignition are accelerated, mainly due to enhanced mixing facilitated by the higher scalar dissipation rates. Furthermore, the sensitivity studies for the jet in wake configuration show a significant reduction in ignition delay even for about 0.14% (by volume) hydrogen dilution in the oxidizer. In addition, the detailed autoignition chemistry and the relative roles of certain radical species in the initiation of the autoignition process in these non-premixed jets are investigated by tracking the evolution of important chain reactions using a Lagrangian particle tracking approach. The reaction H2 + O2 ↔ HO2 + H is recognized to be the dominant chain initiation reaction that provides H radicals essential for the progress of subsequent elementary reactions during the pre-ignition stage.
Plasma-enhanced atomic layer deposition of highly transparent zinc oxy-sulfide thin films
Authors: Bugot C. , Schneider N. , Lincot D. , Donsanti F.
Published: May 2018

The potential of Plasma Enhanced Atomic Layer Deposition (PEALD) for the synthesis of zinc oxy-sulfide Zn(O,S) thin films was explored for the first time, using a supercycle strategy and DEZ, Ar/O2 plasma and H2S as precursors. The growth and the properties of the material were studied by varying the pulse ratio on the full range of composition and the process temperature from Tdep = 120 °C to 220 °C. PEALD-Zn(O,S) films could be grown from pure ZnO to pure ZnS compositions by varying the H2S/(O2 plasma + H2S) pulse ratio. Three distinct growth modes were identified depending on the nature of exchange mechanisms at the film surface during the growth. Films globally have an amorphous structure, except for the extremely sulfur-rich or sulfur-poor ones. High transmission values (up to 85% for Zn(O,S) for 500 < λ < 2500 nm) and optical band gaps (3.3–3.8 eV) have been obtained. The PEALD-Zn(O,S) process and the thin film properties were compared with ALD-Zn(O,S) to highlight the specificities, disadvantages and benefits of plasma enhancement for the synthesis of multi-element materials.
Microcavity enhanced single photon emission from two-dimensional WSe2
Authors: Flatten L. C. , Weng L. , Branny A. , Johnson S. , Dolan P. R. , Trichet A. A. P. , Gerardot B. D. , Smith J. M.
Published: May 2018

Atomically flat semiconducting materials such as monolayer WSe2 hold great promise for novel optoelectronic devices. Recently, quantum light emission has been observed from bound excitons in exfoliated WSe2. As part of developing optoelectronic devices, the control of the radiative properties of such emitters is an important step. Here, we report the coupling of a bound exciton in WSe2 to open microcavities. We use a range of radii of curvature in the plano-concave cavity geometry with mode volumes in the λ3 regime, giving Purcell factors of up to 8 while increasing the photon flux five-fold. Additionally, we determine the quantum efficiency of the single photon emitter to be η=0.46±0.03. Our findings pave the way to cavity-enhanced monolayer based single photon sources for a wide range of applications in nanophotonics and quantum information technologies.
Transient dynamics of NbOx threshold switches explained by Poole-Frenkel based thermal feedback mechanism
Authors: Wang Ziwen , Kumar Suhas , Nishi Yoshio , Wong H.-S. Philip
Published: May 2018

Niobium oxide (NbOx) two-terminal threshold switches are potential candidates as selector devices in crossbar memory arrays and as building blocks for neuromorphic systems. However, the physical mechanism of NbOx threshold switches is still under debate. In this paper, we show that a thermal feedback mechanism based on Poole-Frenkel conduction can explain both the quasi-static and the transient electrical characteristics that are experimentally observed for NbOx threshold switches, providing strong support for the validity of this mechanism. Furthermore, a clear picture of the transient dynamics during the thermal-feedback-induced threshold switching is presented, providing useful insights required to model nonlinear devices where thermal feedback is important.
Experiments on the effects of nanoparticles on subcooled nucleate pool boiling
Authors: Kangude Prasad , Bhatt Dhairya , Srivastava Atul
Published: May 2018

The effect of nanoparticles on a single bubble-based nucleate pool boiling phenomenon under subcooled conditions has been studied. Water (as the base fluid) and two different concentrations of water-silica nanofluids (0.005% and 0.01% V/V) have been employed as the working fluids. The boiling experiments have been conducted in a specially designed chamber, wherein an ITO-coated heater substrate has been used to induce single bubble nucleation. Measurements have been performed in a completely non-intrusive manner using one of the refractive index-based diagnostics techniques, namely, rainbow schlieren deflectometry. Thus, the thermal gradients prevailing in the boiling chamber have directly been mapped as a two-dimensional distribution of hue values that are recorded in the form of rainbow schlieren images. The schlieren-based measurements clearly revealed the plausible influence of nanoparticles on the strength of temperature gradients prevailing in the boiling chamber. As compared to the base fluid, the experiments with dilute nanofluids showed that the suspended nanoparticles tend to diffuse (homogenize) the strength of temperature gradients, both in the vicinity of the heated substrate and in the thermal boundary layer enveloping the vapor bubble. An overall reduction in the bubble volume and dynamic contact angle was seen with increasing concentrations of dilute nanofluids. In addition, the vapor bubble was found to assume a more spherical shape at higher concentrations of dilute nanofluids in comparison to its shape with water-based experiments. Clear oscillations of the vapor bubble in the subcooled pool of liquids (water and/or nanofluids) were observed, the frequency of which was found to be significantly reduced as the nanoparticle concentration was increased from 0% (water) to 0.01% (V/V). A force balance analysis has been performed to elucidate the plausible mechanisms explaining the observed trends of the oscillation frequencies of the vapor bubble.
Ultrafast active control of UV light with plasmonic resonance on aluminum nanostripes
Authors: Wang Kuidong , Li Runze , Hsiao Hui-Hsin , Chen Long , Zhang Haijuan , Chen Jie
Published: May 2018

Ultrafast active control of UV light with aluminum may become an efficient way for high-speed active UV devices. However, the nonlinear optical response of aluminum in the UV region is extremely small, which impedes the realization of the promising modulation depth on ultrafast control. Here, by using the surface plasmon resonance effect, we have achieved a 55-times enhancement in the modulation depth, as well as a short switching time of several picoseconds. Further investigation showed that such an enhancement mainly resulted from a two-order-of-magnitude boost in the response of the signal light to the lattice thermal variation at the plasmonic resonance condition. This improvement in the probing sensitivity could serve as an effective approach to resolve the dynamics of lattice vibrations in metals.
Gyrokinetic simulation study of magnetic island effects on neoclassical physics and micro-instabilities in a realistic KSTAR plasma
Authors: Kwon Jae-Min , Ku S. , Choi M. J. , Chang C. S. , Hager R. , Yoon E. S. , Lee H. H. , Kim H. S.
Published: May 2018

We perform gyrokinetic simulations to study the effects of a stationary magnetic island on neoclassical flow and micro-instability in a realistic KSTAR plasma condition. Through the simulations, we aim to analyze a recent KSTAR experiment, which was to measure the details of poloidal flow and fluctuation around a stationary (2, 1) magnetic island [M. J. Choi et al., Nucl. Fusion 57, 126058 (2017)]. From the simulations, it is found that the magnetic island can significantly enhance the equilibrium E × B flow. The corresponding flow shearing is strong enough to suppress a substantial portion of ambient micro-instabilities, particularly ∇Te-driven trapped electron modes. This implies that the enhanced E × B flow can sustain a quasi-internal transport barrier for Te in an inner region neighboring the magnetic island. The enhanced E × B flow has a (2, 1) mode structure with a finite phase shift from the mode structure of the magnetic island. It is shown that the flow shear and the fluctuation suppression patterns implied from the simulations are consistent with the observations on the KSTAR experiment.
Absorption coefficients of silicon: A theoretical treatment
Authors: Tsai Chin-Yi
Published: May 2018

A theoretical model with explicit formulas for calculating the optical absorption and gain coefficients of silicon is presented. It incorporates direct and indirect interband transitions and considers the effects of occupied/unoccupied carrier states. The indirect interband transition is calculated from the second-order time-independent perturbation theory of quantum mechanics by incorporating all eight possible routes of absorption or emission of photons and phonons. Absorption coefficients of silicon are calculated from these formulas. The agreements and discrepancies among the calculated results, the Rajkanan-Singh-Shewchun (RSS) formula, and Green's data are investigated and discussed. For example, the RSS formula tends to overestimate the contributions of indirect transitions for cases with high photon energy. The results show that the state occupied/unoccupied effect is almost negligible for silicon absorption coefficients up to the onset of the optical gain condition where the energy separation of Quasi-Femi levels between electrons and holes is larger than the band-gap energy. The usefulness of using the physics-based formulas, rather than semi-empirical fitting ones, for absorption coefficients in theoretical studies of photovoltaic devices is also discussed.
Eigenstates and dynamics of Hooke’s atom: Exact results and path integral simulations
Authors: Gholizadehkalkhoran Hossein , Ruokosenmäki Ilkka , Rantala Tapio T.
Published: May 2018

The system of two interacting electrons in one-dimensional harmonic potential or Hooke’s atom is considered, again. On one hand, it appears as a model for quantum dots in a strong confinement regime, and on the other hand, it provides us with a hard test bench for new methods with the “space splitting” arising from the one-dimensional Coulomb potential. Here, we complete the numerous previous studies of the ground state of Hooke’s atom by including the excited states and dynamics, not considered earlier. With the perturbation theory, we reach essentially exact eigenstate energies and wave functions for the strong confinement regime as novel results. We also consider external perturbation induced quantum dynamics in a simple separable case. Finally, we test our novel numerical approach based on real-time path integrals (RTPIs) in reproducing the above. The RTPI turns out to be a straightforward approach with exact account of electronic correlations for solving the eigenstates and dynamics without the conventional restrictions of electronic structure methods.
Resonant intersubband polariton-LO phonon scattering in an optically pumped polaritonic device
Authors: Manceau J.-M. , Tran N.-L. , Biasiol G. , Laurent T. , Sagnes I. , Beaudoin G. , De Liberato S. , Carusotto I. , Colombelli R.
Published: May 2018

We report experimental evidence of longitudinal optical (LO) phonon-intersubband polariton scattering processes under resonant injection of light. The scattering process is resonant with both the initial (upper polariton) and final (lower polariton) states and is induced by the interaction of confined electrons with longitudinal optical phonons. The system is optically pumped with a mid-IR laser tuned between 1094 cm−1 and 1134 cm−1 (λ = 9.14 μm and λ = 8.82 μm). The demonstration is provided for both GaAs/AlGaAs and InGaAs/AlInAs doped quantum well systems whose intersubband plasmon lies at a wavelength of ≈10 μm. In addition to elucidating the microscopic mechanism of the polariton-phonon scattering, it is found to differ substantially from the standard single particle electron-LO phonon scattering mechanism, and this work constitutes an important step towards the hopefully forthcoming demonstration of an intersubband polariton laser.
Metabolic control of T cell immune response through glycans in inflammatory bowel disease
Authors: Dias Ana M. , Correia Alexandra , Pereira Márcia S. , Almeida Catarina R. , Alves Inês , Pinto Vanda , Catarino Telmo A. , Mendes Nuno , Leander Magdalena , Oliva-Teles M. Teresa , Maia Luís , Delerue-Matos Cristina , Taniguchi Naoyuki , Lima Margarida , Pedroto Isabel , Marcos-Pinto Ricardo , Lago Paula , Reis Celso A. , Vilanova Manuel , Pinho Salomé S.
Published: May 2018

Significance

Our findings demonstrate that metabolic supplementation of mucosal T cells, isolated from patients with active ulcerative colitis (UC), with
N
-acetylglucosamine (GlcNAc) leads to the enhancement of branched N-glycosylation on the T cell receptor, which was associated with the control of T cell activation and function. These results were validated in “glycoengineered” mouse models with severe colitis. Overall, our results open new avenues for a targeted-specific therapy in inflammatory bowel disease (IBD). The therapeutic use of GlcNAc (either alone or in combination with other antiinflammatory therapies) represents a simple immunomodulatory strategy in IBD, with absence of side effects, low costs, and the possibility of being used as a simple rescue therapy to avoid unnecessary toxic effects and step-up therapies in IBD.
Plant acclimation to long-term high nitrogen deposition in an N-rich tropical forest
Authors: Lu Xiankai , Vitousek Peter M. , Mao Qinggong , Gilliam Frank S. , Luo Yiqi , Zhou Guoyi , Zou Xiaoming , Bai Edith , Scanlon Todd M. , Hou Enqing , Mo Jiangming
Published: May 2018

Significance

Elevated atmospheric N deposition threatens ecosystem health through eutrophication in terrestrial ecosystems, but little is known about consequences of N deposition in N-rich tropical ecosystems. We added several levels of N to an N-rich tropical forest and monitored plant growth dynamics, forest nutrient status, plant water use, and water losses from the ecosystem for a decade. We found that plants can acclimate and maintain nutrient balance by altering hydrological cycling. These results demonstrate that while elevated N deposition to already N-rich tropical forests may have minor effects on forest growth, it can exert a detectable influence on hydrological dynamics. Reduced runoff may threaten water supply in rapidly developing tropical regions.
Lipidomic profiling reveals soluble epoxide hydrolase as a therapeutic target of obesity-induced colonic inflammation
Authors: Wang Weicang , Yang Jun , Zhang Jianan , Wang Yuxin , Hwang Sung Hee , Qi Weipeng , Wan Debin , Kim Daeyoung , Sun Jia , Sanidad Katherine Z. , Yang Haixia , Park Yeonhwa , Liu Jun-Yan , Zhao Xinfeng , Zheng Xiaohui , Liu Zhenhua , Hammock Bruce D. , Zhang Guodong
Published: May 2018

Significance

Obesity is associated with enhanced colonic inflammation, which is a major risk factor for colorectal cancer. To date, the mechanisms by which obesity increases colonic inflammation are not well-understood, and there are few effective strategies for controlling obesity-induced colonic inflammation and associated diseases. Here, using LC-MS/MS–based metabolomics, we report that soluble epoxide hydrolase (sEH) could be a novel therapeutic target for obesity-induced colonic inflammation. This could lead to rapid human translation, as pharmacological inhibitors of sEH are being evaluated in human clinical trials targeting multiple disorders.
Roughness-dependent tribology effects on discontinuous shear thickening
Authors: Hsu Chiao-Peng , Ramakrishna Shivaprakash N. , Zanini Michele , Spencer Nicholas D. , Isa Lucio
Published: May 2018

Significance

Shear thickening is a ubiquitous rheological phenomenon whereby dense suspensions of particles in a fluid exhibit a viscosity increase at high shear, which can turn into a viscosity divergence [discontinuous shear thickening (DST)]. Although macroscopically well characterized, the microscopic origin of DST is still debated, especially in connection to particle surface properties, e.g., roughness and friction. We elucidate here the mechanisms underpinning DST by carrying out nanotribological measurements of the interparticle contacts of model rough colloids. We demonstrate that rough particles exhibit DST over a broader range of shear rates and for volume fractions much lower than for smooth colloids, due to interlocking of surface asperities, showing that taking an engineering-tribology approach is a powerful way to tune DST.
Divergent drivers of leaf trait variation within species, among species, and among functional groups
Authors: Osnas Jeanne L. D. , Katabuchi Masatoshi , Kitajima Kaoru , Wright S. Joseph , Reich Peter B. , Van Bael Sunshine A. , Kraft Nathan J. B. , Samaniego Mirna J. , Pacala Stephen W. , Lichstein Jeremy W.
Published: May 2018

Significance

Leaf traits, such as photosynthetic capacity, nitrogen concentration, and leaf mass per area, strongly affect plant growth and nutrient cycles. Understanding relationships among leaf traits is, therefore, a fundamental challenge in plant biology, crop science, and ecology. Different groups of leaves exhibit distinct relationships among pairs of traits. For example, photosynthetic capacity per unit leaf area increases strongly with leaf mass per area from sun to shade within species, but these same traits are only weakly related across global species. Our analysis suggests that divergent trait relationships can be understood by partitioning leaf mass into photosynthetic and structural support components. Our paper clarifies the causes of relationships among traits and why those relationships differ among different groups of plants.
Evolution of increased competitive ability and shifting defence hypotheses.
Authors: Müller C.
Published: May 2018

This chapter focuses on two of the various hypotheses that take into account the role of biotic interactions in invasion biology, namely the evolution of increased competitive ability (EICA) hypothesis and the shifting defence hypothesis (SDH). Both hypotheses mainly consider changes in concentrations of chemical defences in plant individuals from native vs exotic populations and are studied independently of the novelty of the chemical metabolite in the invasive range. The EICA hypothesis predicts that chemical defences should be lower in plants of invasive populations because enemy pressure is reduced in the exotic range. The SDH predicts a shift in chemical defences by discriminating between qualitative and quantitative defences. Qualitative defences (toxins) are cheaper to produce and expected to increase in invasive populations because they are needed as defence against generalists, whereas expensive quantitative defences (digestibility reducers) may be reduced in plants of the invasive range owing to the overall lower enemy pressure. Methodological issues are pointed out that should be considered when testing the differences in plant traits between native and invasive populations. A literature review on qualitative and quantitative defence traits, which were compared between plants of native and invasive origin grown under standardized common-garden conditions, revealed 37 studies, comprising 22 plant species. The results of the review infrequently support predictions for defence distributions of the EICA hypothesis, whereas predictions of the SDH are supported by somewhat more traits. The definition of qualitative vs quantitative defences has shortcomings, however. In particular, actual costs of these defences are difficult to estimate but should be investigated in future studies. Furthermore, instead of focusing on individual defences, multiple defences should be considered in plant species that are invasive to gain a more complete understanding of resource-allocation patterns.
Numerical modelling and experimental investigation of thermal and material flow in probeless friction stir spot welding process of Al 2198-T8
Authors: Yang Xiawei , Feng Wuyuan , Li Wenya , Xu Yaxin , Chu Qiang , Ma Tiejun , Wang Weibing
Published: May 2018

A finite element model based on software Abaqus/Explicit and experimentation was established to describe the probeless friction stir spot welding process of 2198-T8 aluminium alloy. An Arbitrary Lagrangian–Eulerian method was adopted in this model in which the Johnson–Cook equation was used to describe the flow stress depending on temperature, plastic strain and strain rate. The experimental results revealed the representative microstructure of the joint which has three typical zones: stir zone, thermo mechanically affected zone and heat affected zone. The relationship between the temperature field and dwell time was investigated based on the accurate description of temperature field. A model of the material flow was developed based on the numerical and experimental results.
Analytic treatment of the thermoelectric properties for two coupled
quantum dots threaded by magnetic fields
Authors: Menichetti G , Grosso G , Parravicini G Pastori
Published: May 2018

Coupled double quantum dots (c-2QD) connected to leads have been widely adopted
as prototype model systems to verify interference effects on quantum transport
at the nanoscale. We provide here an analytic study of the thermoelectric
properties of c-2QD systems pierced by a uniform magnetic field. Fully analytic
and easy-to-use expressions are derived for all the kinetic functionals of
interest. Within the Green’s function formalism, our
results allow a simple inexpensive procedure for the theoretical description of
the thermoelectric phenomena for different chemical potentials and temperatures
of the reservoirs, different threading magnetic fluxes, dot energies and
interdot interactions; moreover they provide an intuitive guide to parametrize
the system Hamiltonian for the design of best performing realistic devices. We
have found that the thermopower S can be enhanced by more than
ten times and the figure of merit ZT by more than hundred times
by the presence of a threading magnetic field. Most important, we show that the
magnetic flux increases also the performance of the device under maximum power
output conditions.
The Contribution of Genetic Variation of Streptococcus pneumoniae to the Clinical Manifestation of Invasive Pneumococcal Disease
Authors: Cremers Amelieke J H , Mobegi Fredrick M , van der Gaast–de Jongh Christa , van Weert Michelle , van Opzeeland Fred J , Vehkala Minna , Knol Mirjam J , Bootsma Hester J , Välimäki Niko , Croucher Nicholas J , Meis Jacques F , Bentley Stephen , van Hijum Sacha A F T , Corander Jukka , Zomer Aldert L , Ferwerda Gerben , de Jonge Marien I
Published: May 2018

Background

Different clinical manifestations of invasive pneumococcal disease (IPD) have thus far mainly been explained by patient characteristics. Here we studied the contribution of pneumococcal genetic variation to IPD phenotype.

Methods

The index cohort consisted of 349 patients admitted to 2 Dutch hospitals between 2000–2011 with pneumococcal bacteremia. We performed genome-wide association studies to identify pneumococcal lineages, genes, and allelic variants associated with 23 clinical IPD phenotypes. The identified associations were validated in a nationwide (n = 482) and a post–pneumococcal vaccination cohort (n = 121). The contribution of confirmed pneumococcal genotypes to the clinical IPD phenotype, relative to known clinical predictors, was tested by regression analysis.

Results

Among IPD patients, the presence of pneumococcal gene slaA was a nationwide confirmed independent predictor of meningitis (odds ratio [OR], 10.5; P = .001), as was sequence cluster 9 (serotype 7F: OR, 3.68; P = .057). A set of 4 pneumococcal genes co-located on a prophage was a confirmed independent predictor of 30-day mortality (OR, 3.4; P = .003). We could detect the pneumococcal variants of concern in these patients’ blood samples.

Conclusions

In this study, knowledge of pneumococcal genotypic variants improved the clinical risk assessment for detrimental manifestations of IPD. This provides us with novel opportunities to target, anticipate, or avert the pathogenic effects related to particular pneumococcal variants, and indicates that information on pneumococcal genotype is important for the diagnostic and treatment strategy in IPD. Ongoing surveillance is warranted to monitor the clinical value of information on pneumococcal variants in dynamic microbial and susceptible host populations.
Assessing Dependency in a Multiethnic Community Cohort of Individuals With Alzheimer’s Disease
Authors: Meinerding Maria , DeFeis Brittany , Sunderaraman Preeti , Azar Martina , Lawless Siobhan , Perez-Vivaldo Carlos , Gu Yian , Stern Yaakov , Cosentino Stephanie
Published: May 2018

Background and Objectives

Clinic-based studies of patients with Alzheimer’s disease (AD) have demonstrated the value of assessing dependence when characterizing patients’ functional status. The Dependence Scale, a validated tool to assess level of caregiving needs, is associated with markers of disease severity, cost, and progression, while offering independent functional information about patients. This study examines whether such associations between the Dependence Scale and markers of disease severity demonstrated in clinical cohorts are similarly exhibited in a multiethnic community population of individuals with AD.

Research Design and Methods

One hundred fifty four elders with AD enrolled in the Predictors 3 cohort were assessed with the Dependence Scale, modified Mini-Mental State Examination (mMMS), instrumental (IADL) and basic (BADL) activities of daily living, and Clinical Dementia Rating (CDR) Scale, and were assigned an Equivalent Institutional Care (EIC) rating. Cross-sectional associations were examined using bivariate correlations and one-way analysis of variance analyses. Fisher-z tests examined differences in strengths of associations across previous clinic and current community cohorts.

Results

Dependence Scale scores were associated with CDR (r = .20, p = .013), mMMS (r = −.23, p = .005), IADL (r = .39, p < .001), BADL (r = .65, p < .001), and EIC (r = .51, p < .001). Dependence was unassociated with ethnicity (F[3,144] = 1.027, p = .3822), age (r = .120, p = .145), and education (r = −.053, p = .519). The strength of the correlations was comparable across cohorts except that BADLs were more strongly associated with dependence (z = −4.60, p < .001) in the community cohort, and living arrangement was not associated with dependence (r = .13, p = .130).

Discussion and Implications

Associations between the Dependence Scale and markers of disease severity in a clinic-based cohort of AD patients are similar to associations in a multiethnic community cohort of individuals diagnosed with AD. The Dependence Scale relates to markers of disease severity rather than demographic factors, and may offer an unbiased assessment of care required in multiethnic and community populations.
Optimized distributed systems achieve significant performance improvement on sorted merging of massive VCF files
Authors: Sun Xiaobo , Gao Jingjing , Jin Peng , Eng Celeste , Burchard Esteban G , Beaty Terri H , Ruczinski Ingo , Mathias Rasika A , Barnes Kathleen , Wang Fusheng , Qin Zhaohui S ,   CAAPA consortium
Published: May 2018

Background

Sorted merging of genomic data is a common data operation necessary in many sequencing-based studies. It involves sorting and merging genomic data from different subjects by their genomic locations. In particular, merging a large number of variant call format (VCF) files is frequently required in large-scale whole-genome sequencing or whole-exome sequencing projects. Traditional single-machine based methods become increasingly inefficient when processing large numbers of files due to the excessive computation time and Input/Output bottleneck. Distributed systems and more recent cloud-based systems offer an attractive solution. However, carefully designed and optimized workflow patterns and execution plans (schemas) are required to take full advantage of the increased computing power while overcoming bottlenecks to achieve high performance.

Findings

In this study, we custom-design optimized schemas for three Apache big data platforms, Hadoop (MapReduce), HBase, and Spark, to perform sorted merging of a large number of VCF files. These schemas all adopt the divide-and-conquer strategy to split the merging job into sequential phases/stages consisting of subtasks that are conquered in an ordered, parallel, and bottleneck-free way. In two illustrating examples, we test the performance of our schemas on merging multiple VCF files into either a single TPED or a single VCF file, which are benchmarked with the traditional single/parallel multiway-merge methods, message passing interface (MPI)–based high-performance computing (HPC) implementation, and the popular VCFTools.

Conclusions

Our experiments suggest all three schemas either deliver a significant improvement in efficiency or render much better strong and weak scalabilities over traditional methods. Our findings provide generalized scalable schemas for performing sorted merging on genetics and genomics data using these Apache distributed systems.
Assessment of rosacea symptom severity by genome-wide association study and expression analysis highlights immuno-inflammatory and skin pigmentation genes
Authors: Aponte Jennifer L , Chiano Mathias N , Yerges-Armstrong Laura M , Hinds David A , Tian Chao , Gupta Akanksha , Guo Cong , Fraser Dana J , Freudenberg Johannes M , Rajpal Deepak K , Ehm Margaret G , Waterworth Dawn M
Published: May 2018

Rosacea is a common, chronic skin disease of variable severity with limited treatment options. The cause of rosacea is unknown, but it is believed to be due to a combination of hereditary and environmental factors. Little is known about the genetics of the disease. We performed a genome-wide association study (GWAS) of rosacea symptom severity with data from 73 265 research participants of European ancestry from the 23andMe customer base. Seven loci had variants associated with rosacea at the genome-wide significance level (P < 5 × 10−8). Further analyses highlighted likely gene regions or effector genes including IRF4 (P = 1.5 × 10−17), a human leukocyte antigen (HLA) region flanked by PSMB9 and HLA-DMB (P = 2.2 × 10−15), HERC2-OCA2 (P = 4.2 × 10−12), SLC45A2 (P = 1.7 × 10−10), IL13 (P = 2.8 × 10−9), a region flanked by NRXN3 and DIO2 (P = 4.1 × 10−9), and a region flanked by OVOL1and SNX32 (P = 1.2 × 10−8). All associations with rosacea were novel except for the HLA locus. Two of these loci (HERC-OCA2 and SLC45A2) and another precedented variant (rs1805007 in melanocortin 1 receptor) with an association P value just below the significance threshold (P = 1.3 × 10−7) have been previously associated with skin phenotypes and pigmentation, two of these loci are linked to immuno-inflammation phenotypes (IL13 and PSMB9-HLA-DMA) and one has been associated with both categories (IRF4). Genes within three loci (PSMB9-HLA-DMA, HERC-OCA2 and NRX3-DIO2) were differentially expressed in a previously published clinical rosacea transcriptomics study that compared lesional to non-lesional samples. The identified loci provide specificity of inflammatory mechanisms in rosacea, and identify potential pathways for therapeutic intervention.
Comparing Negative Attitudes Toward the Unemployed Across European Countries in 2008 and 2016: The Role of the Unemployment Rate and Job Insecurity
Authors: Buffel Veerle , Van de Velde Sarah
Published: May 2018

We explore how negative attitudes toward the unemployed are related to countries’ overall and long-term (LT) unemployment rate. Insights from the risk attribution and position theory are combined with the in-group–out-group conflict model, derived from migration literature. Multilevel analyses are performed on two waves (2008 and 2016) of the European Social Survey. Negative attitudes toward the unemployed are measured via the item “most unemployed people do not really try to find a job.” Results show that in countries with a high LT unemployment rate and/or an increase in this rate, people are more likely to hold negative attitudes toward the unemployed. Moreover, this is more pronounced among people in secure job conditions (those with a permanent contract and/or perceiving job security).
Accuracy of the medication list in the electronic health record—implications for care, research, and improvement
Authors: Walsh Kathleen E , Marsolo Keith A , Davis Cori , Todd Theresa , Martineau Bernadette , Arbaugh Carlie , Verly Frederique , Samson Charles , Margolis Peter
Published: May 2018

Objective

Electronic medication lists may be useful in clinical decision support and research, but their accuracy is not well described. Our aim was to assess the completeness of the medication list compared to the clinical narrative in the electronic health record.

Methods

We reviewed charts of 30 patients with inflammatory bowel disease (IBD) from each of 6 gastroenterology centers. Centers compared IBD medications from the medication list to the clinical narrative.

Results

We reviewed 379 IBD medications among 180 patients. There was variation by center, from 90% patients with complete agreement between the medication list and clinical narrative to 50% agreement.

Conclusions

There was a range in the accuracy of the medication list compared to the clinical narrative. This information may be helpful for sites seeking to improve data quality and those seeking to use medication list data for research or clinical decision support.
CE: Understanding the Nurse's Role in Managing Gaucher Disease
Authors: Vucko Erika R.
Published: May 2018

Lysosomal storage disorders (LSDs) are a group of inherited metabolic conditions, the overall incidence of which is estimated to range from one in 5,000 to one in 7,000 live births. Gaucher disease, the most common LSD, is of autosomal recessive inheritance. It results from a deficiency of acid β-glucocerebrosidase and can affect the spleen, liver, bone, bone marrow, and central nervous system. Gaucher disease is clinically classified into one of three phenotypes, depending on the absence or presence of neurodegenerative disease and the rate of disease progression. Although there is no cure for Gaucher disease, it may be treated with enzyme replacement and substrate reduction therapy. With the development of enzyme testing through dried blood spots, Gaucher disease may now be detected at birth through newborn screening. The purpose of this article is to review the epidemiology and pathophysiology of Gaucher disease, update nurses on advances in newborn screening, diagnosis, and management of this genetic disorder, and highlight the role of nurses in the diagnosis and care of patients with Gaucher disease.
Family history of substance use disorder and chronic pain management
Authors: Pestka Elizabeth L. , Evans Michele
Published: May 2018

The use of family history of substance use disorder information as part of a comprehensive assessment of chronic pain can provide important data for treatment. This case example illustrates assessment, patient education, and brief motivational interviewing with referral to appropriate resources.
Ultrasound-guided Pulsed Radiofrequency in the Management of Thoracic Postherpetic Neuralgia
Authors: Makharita Mohamed Y. , El Bendary Hanaa M. , Sonbul Zainab M. , Ahmed Salma E.S. , Latif Mahmoud A.
Published: May 2018

Objectives:

This study was designed to evaluate the efficacy and safety of ultrasound-guided pulsed radiofrequency (PRF) for the intercostal nerves (ICNs) in the management of thoracic postherpetic neuralgia.

Methods:

After 2 weeks of treatment by pregabalin 150 mg/12 hours, patients were randomly allocated into 2 groups. The PRF group, after ultrasound-guided localization of the ICN of the affected thoracic dermatome, sensory stimulation of the ICN was tested. Thereafter, the patient received 2 cycles PRF at 42°C temperature, for 120 seconds. The sham group, after stimulation, the same time was spent to mimic PRF. The same procedures were repeated to the upper and lower adjacent ICNs. Pain intensity using Visual Analogue Scale (VAS), and total analgesics consumption were assessed at the baseline, every 2 weeks for 6 months then after 9 and 12 months. The duration of effective pain relief was recorded. Quality of life was evaluated using self-evaluation questionnaires (SF-36) at baseline then after 1, 3, 6, and 12 months.

Results:

PRF group expressed a significant decrease on the VAS throughout the study period. VAS<30 was reported in the PRF group until the 22nd week. Pregabalin and acetaminophen consumption was significantly lower in the PRF group. The 8 domains of the SF-36 revealed a significant improvement in the PRF group when compared with the sham group throughout the study period except for the physical role which displayed nonsignificant improvement.

Conclusions:

Ultrasound-guided PRF for ICNs in combination with pharmacotherapy seems to be a safe and effective treatment modality for postherpetic neuralgia.
Utilizing T-cell Activation Signals 1, 2, and 3 for Tumor-infiltrating Lymphocytes (TIL) Expansion: The Advantage Over the Sole Use of Interleukin-2 in Cutaneous and Uveal Melanoma
Authors: Tavera René J. , Forget Marie-Andrée , Kim Young Uk , Sakellariou-Thompson Donastas , Creasy Caitlin A. , Bhatta Ankit , Fulbright Orenthial J. , Ramachandran Renjith , Thorsen Shawne T. , Flores Esteban , Wahl Arely , Gonzalez Audrey M. , Toth Christopher , Wardell Seth , Mansaray Rahmatu , Radvanyi Laszlo G. , Gombos Dan S. , Patel Sapna P. , Hwu Patrick , Amaria Rodabe N. , Bernatchez Chantale , Haymaker Cara
Published: May 2018

In this study, we address one of the major critiques for tumor-infiltrating lymphocyte (TIL) therapy—the time needed for proper expansion of a suitable product. We postulated that T-cell receptor activation in the first phase of expansion combined with an agonistic stimulation of CD137/4-1BB and interleukin-2 would favor preferential expansion of CD8+ TIL. Indeed, this novel 3-signal approach for optimal T-cell activation resulted in faster and more consistent expansion of CD8+CD3+ TIL. This new method allowed for successful expansion of TIL from cutaneous and uveal melanoma tumors in 100% of the cultures in <3 weeks. Finally, providing the 3 signals attributed to optimal T-cell activation led to expansion of TIL capable of recognizing their tumor counterpart in cutaneous and uveal melanoma. This new methodology for the initial phase of TIL expansion brings a new opportunity for translation of TIL therapy in challenging malignancies such as uveal melanoma.
Classification of Foreign Body Reactions due to Industrial Silicone Injection
Authors: Harlim Ago , Kanoko Mpu , Aisah Siti
Published: May 2018

BACKGROUND

A foreign body reaction (FBR) is a typical tissue response to a biomaterial that has been injected or implanted in human body tissue. There has been a lack of data on the classification of foreign body reaction to silicone injection, which can describe the pattern of body tissue responses to silicone.

OBJECTIVE

Determine the foreign body reaction to silicone injection.

METHOD

We modified the classification proposed by Duranti and colleagues, which has categorized a FBR to hyaluronic acid injection into a new classification of an FBR to silicone injection. A cohort study of 31 women suffering from silicone-induced granulomas on their chin was conducted. Granulomatous tissue and submental skin were stained with hematoxylin–eosin and evaluated.

RESULTS

Our data revealed that there were at least 7 categories of FBRs to silicone injection that could be developed. Categories 1 to 4 showed inflammatory activity, and categories 5 to 8 showed tissue repair by fibrosis.

CONCLUSION

Using histopathological staining, we are able to sequence the steps of body reactions to silicone injection. Initial inflammatory reaction is then replaced by fibrosis process repairing the damaged tissues. The process depends on the host immune tolerance.