bluuebunny/crossref_metadata_2025 huggingface dataset:
Resolving power beyond the diffraction limit demonstrated with composed pupils at microwave and THz frequencies
Authors: Cacciari I. , Mugnai D. , Ranfagni A.
Published: January 2019

In order to increase the resolving power of an optical system, the results obtained with super-gain antennas could be transferred to optics as proposed by Toraldo di Francia since 1952, with the adoption of special kinds of pupils consisting of concentric circular slits. Experimental work performed in the microwave range confirms the correctness of the theoretical predictions. In addition, experiments performed in the terahertz range give further evidence of the increased resolving power. The improvement of the resolving power results to be comparable with the maximum value predicted by the theoretical model: ∼1.9 for the pupils under test. In both cases, the adopted pupil consists of three circular zones, with the intermediate one made of a suitable dielectric, the thickness of which is about one wavelength. Apparent contradiction with the uncertainty principle can be interpreted in the framework of the “weak measurements” theory, thus supplying an alternative interpretation.
Comprehensive evaluation and parametric sensitivity of interatomic potential models for diffusion kinetics of Cr2O3 in molecular dynamics
Authors: Wang Jiaqi , Shin Dongwon , Shin Seungha
Published: January 2019

While molecular dynamics (MD) has proven to be a promising approach to investigate the diffusion properties, the grand challenge resides in evaluating potential model parameters to accurately replicate experimentally measured properties. The Buckingham potential model with Columbic interaction is widely employed in MD simulations of chromia (Cr2O3) systems, as it allows for reasonable computational cost and accuracy. However, considering the well-known limitation of classical potential models in simultaneous reproduction of various physical phenomena, further comprehensive evaluation of the potential is required for calculation of diffusion properties. In this study, we benchmark the performance of three different Buckingham models with the experimental data by calculating structural, thermodynamic, and mechanical properties of defect-free Cr2O3, and diffusion properties of Cr2O3 with vacancy defects. Available Buckingham models display limited accuracies, consolidating the necessity of retraining the potential parameters for all properties impacting the diffusion dynamics. Oversimplification in parameterization procedures is suggested to impede the universal performance in property reproduction. This research also demonstrates effective guidelines for choosing a proper parameter set of current Buckingham potential for MD simulation with Cr2O3 depending on properties and for potential reparameterization.
New idea of Atangana and Baleanu fractional derivatives to human blood flow in nanofluids
Authors: Khan Ilyas
Published: January 2019

Applications of fractional derivatives are rare for blood flow problems, more exactly in nanofluids. The old definitions published in the literature for fractional derivatives, such as Riemann-Liouville definition, are rarely used by the researchers now; instead, they like to use the new definition introduced by Atangana and Baleanu quite recently. Therefore, in this article, a new idea of Atangana and Baleanu for fractional derivatives possessing a non-local and non-singular kernel has been applied to blood of nanofluids. Blood is considered as a base fluid, and single-wall carbon nanotubes are suspended in blood as nanoparticles in order to make a nanofluid. The magnetic effect with Lorentz force is also taken. The modelled problem is first written in the dimensionless form and later on solved by using an integral transform of Laplace. The effects of embedded parameters are shown in various plots on blood flow and temperature. The heart transfer rate is computed numerically in a tabular form. The results showed that Atangana and Baleanu fractional parameter slow down the blood motion, whereas increasing nanoparticles’ volume fraction causes a significant increase in the heat transfer rate.
Gyrotron multistage depressed collector based on E × B drift concept using azimuthal electric field. II: Upgraded designs
Authors: Wu Chuanren , Pagonakis Ioannis Gr. , Albert David , Avramidis Konstantinos A. , Gantenbein Gerd , Illy Stefan , Thumm Manfred , Jelonnek John
Published: January 2019

Multistage Depressed Collectors (MDCs) are nontrivial for high-frequency gyrotrons. A basic conceptual design of an E×B MDC using azimuthal electric fields was proposed in Part I of this series. In the present work, several upgraded design proposals based on the basic one will be elaborated. These proposals will significantly reduce the back-stream of electrons, which was the main drawback of the basic design proposal. Another upgraded design proposal will shrink the length and maximal radius of the MDC to be only a fraction of its full-length version. A conceptual design of the final MDC proposal will be given at the end.
Non-photochemical laser-induced nucleation
Authors: Alexander Andrew J. , Camp Philip J.
Published: January 2019

Non-photochemical laser-induced nucleation (NPLIN) is the formation of a new phase from a metastable phase by the action of light on matter. Using millijoule, nanosecond laser pulses at visible and near-infrared wavelengths, it is possible to form the new phase localized in the volume of the beam. In the case of nucleating molecular solids, the laser polarization may have an effect on the particular polymorph that is formed. Despite the huge potential for applications of NPLIN, there is uncertainty regarding the molecular-scale mechanism, and various possible scenarios may well be relevant to nucleation in general and not just NPLIN. In this Perspective, the discovery and phenomenology of NPLIN are described, putative mechanisms are outlined, and some observations on the broader class of nucleation phenomena are given.
Wide range doping controllability of p-type GaN films prepared via pulsed sputtering
Authors: Fudetani Taiga , Ueno Kohei , Kobayashi Atsushi , Fujioka Hiroshi
Published: January 2019

The growth of Mg-doped GaN over a wide doping range is demonstrated via pulsed sputtering deposition (PSD). All samples show p-type conductivity without any post-growth annealing, and their room temperature (RT) hole concentration can be controlled for as much as two orders of magnitude from 2.8 × 1016 cm−3 to 2.7 × 1018 cm−3. No apparent structural degradation is observed, even for the most heavily Mg-doped sample with an RT hole concentration of 2.7 × 1018 cm−3. The compensation ratio is lower than 10% for the heavily Mg-doped samples, which explains the high conductivity of PSD-grown p-type GaN. These results indicate the strong potential of PSD for the growth of high-quality p-type GaN and its application to p–n junction devices.
Stabilization of tearing modes by modulated electron cyclotron current drive
Authors: Zhang W. , Ma Z. W. , Zhang Y. , Zhu J.
Published: January 2019

The influence of modulated-ECCD on m/n=2/1 resistive tearing mode is investigated by a three-dimensional toroidal and non-reduced MHD code CLT. It is found that, after applying a modulated-ECCD, tearing mode instabilities are suppressed and magnetic islands are gradually reduced to a low level, then the width of the magnetic islands exhibit periodic oscillation with the time scale of ECCD modulation frequency. The minimum width of magnetic islands decreases with the decrease of ECCD modulation frequency and increases with the increase of the buildup time of the driven current.
High efficiency color-tunable organic light-emitting diodes with ultra-thin emissive layers in blue phosphor doped exciplex
Authors: Ying Shian , Wu Yibing , Sun Qian , Dai Yanfeng , Yang Dezhi , Qiao Xianfeng , Chen Jiangshan , Ma Dongge
Published: January 2019

High efficiency color-tunable organic light-emitting diodes (CT-OLEDs) have been demonstrated by combining non-doped ultra-thin red and green phosphorescent emitters with a blue phosphorescence-doped exciplex system. The resultant devices deliver a sunlight-style emission with a wide correlated color-temperature span from 2143 to 7563 K and achieve the maximum current efficiency, the power efficiency, and the external quantum efficiency of 34.4 cd A−1, 39.5 lm W−1, and 18.6%, respectively, without any out-coupling enhancements. Furthermore, the CT-OLEDs exhibit low efficiency roll-off that the external quantum efficiencies still remain 18.5% and 17.1% even at 1000 and 5000 cd m−2, respectively, which are more efficient than those of state-of-the-art CT-OLEDs.
High-order two-fluid plasma solver for direct numerical simulations of plasma flows with full transport phenomena
Authors: Li Z. , Livescu D.
Published: January 2019

The two-fluid plasma equations for a single ion species, with full transport terms, including temperature and magnetic field dependent ion and electron viscous stresses and heat fluxes, frictional drag force, and ohmic heating terms, have been implemented in the CFDNS code and solved by using sixth-order non-dissipative compact finite differences for plasma flows in several different regimes. In order to be able to fully resolve all the dynamically relevant time and length scales, while maintaining computational feasibility, the assumptions of infinite speed of light and negligible electron inertia have been made. Non-dimensional analysis of the two-fluid plasma equations shows that, by varying the characteristic/background number density, length scale, temperature, and magnetic strength, the corresponding Hall, resistive, and ideal magnetohydrodynamic equations can be recovered as limiting cases. The accuracy and robustness of this two-fluid plasma solver in handling plasma flows in different regimes have been validated against four canonical problems: Alfven and whistler dispersion relations, electromagnetic plasma shock, and magnetic reconnection. For all test cases, by using physical dissipation and diffusion, with negligible numerical dissipation/diffusion, fully converged Direct Numerical Simulation (DNS)-like solutions are obtained when the ion Reynolds number based on the grid size is smaller than a threshold value which is about 2.3 in this study. For the magnetic reconnection problem, the results show that the magnetic flux saturation time and value converge when the ion and magnetic Reynolds numbers are large enough. Thus, the DNS-like results become relevant to practical problems with much larger Reynolds numbers.
Low-temperature mechanical properties of fullerites: structure, elasticity, plasticity, strength
Authors: Lubenets S. V. , Fomenko L. S. , Natsik V. D. , Rusakova A. V.
Published: January 2019

The results of long-term studies on the physical-mechanical properties of C60 and C70 molecular crystals (fullerites) were systematized and described. These materials are the new allotropic form of carbon in which fullerenes (stable molecules consisting of 60 and 70 atoms) represent the elementary base units. Molecules are combined into crystalline structures mainly by dispersive (van der Waals) forces with a small contribution from covalent bonds. The anomalies of the fullerite crystal structures and features of the phase transitions occurring in them, which are caused by dispersive forces, orientation ordering, and dynamics of the molecules’ rotational degrees of freedom, were discussed. The most interesting transformations of fullerite lattice structures and orientation states were observed in the temperature range of 77 K ≲ Т ≲ 350 K. The majority of the experimental investigations were carried out at these temperatures. The experiments were concentrated on the effects that lattice-orientation phase transitions had on the mechanical properties of single crystals, polycrystalline solids, and compacts. Acoustical spectroscopy at low and high oscillation frequencies, micro- and nanoindentation and macrodeformation methods were used in the experimental research. The crystallogeometric aspects and dislocation mechanisms of plastic slip in fullerites, as well as the methods of observing dislocations and studying their mobility, are described in detail. Also the influence of different external factors, namely, illumination (photoplastic effect), pulsed magnetic field (magnetoplastic effect), and sample compaction pressure (baropolymerization effect) are discussed. The effects of saturating samples of different morphology with hydrogen, oxygen, and inert gas impurities on the fullerites’ mechanical properties were considered. The discussion of the experimental results is accompanied by a brief description of their theoretical interpretation based on analyzing the interaction of elastic and plastic deformations of the fullerite lattice with the processes of orientational ordering, rotation, and librational vibrations of molecules.
Dissipative motion of vortices in spatially inhomogeneous Bose-Einstein condensates
Authors: Zueva T. I.
Published: January 2019

A dissipative model of vortex motion within a two-dimensional Gross-Pitaevskii equation is studied. With the asymptotic coordination method of solutions, a system of ordinary first-order differential equations describing vortex motion in rotating Bose-Einstein condensate was derived. The model takes into account the effect of various external factors: magnetic trap frequencies, number of particles in the condensate, angular rotational velocity of the condensate, dissipation parameter, etc. In special cases of dissipation-free motion, the results are coordinated with the known results of other authors. The addition of dissipation generalizes the known equations and makes it possible to see the vortex motion to the equilibrium points and to define the equilibrium configurations of any number of vortices. The model is illustrated by a large number of examples.
Spin-phonon interaction in transition-metal difluoride antiferromagnets: Theory and experiment
Authors: Cottam M. G. , Lockwood D. J.
Published: January 2019

An overall comparative study is made of the spin-phonon interactions in several rutile-structure transition-metal difluorides, specifically FeF2, MnF2, NiF2, and CoF2, in terms of recent developments obtained experimentally using inelastic light scattering spectroscopy and theoretically using a modified mean-field approach to estimate spin-pair correlation functions. New experimental data are presented here and interpreted within an extended and comprehensive theoretical treatment to yield estimates for the spin-phonon coupling coefficients and the relative magnitudes of the magneto-optical coupling coefficients.
Mechanisms of scattering of surface electrons in topological insulators
Authors: Toporov Yu. V. , Kordyuk A. A.
Published: January 2019

A unique feature of topological insulators is the presence of electronic topologically protected quasiparticle surface states that are exceptionally resistant to impurities; however, the scattering spectrum of these surface quasiparticles is poorly studied. The purpose of this study is to determine the structure of the surface state eigenenergy by analyzing photoemission spectra. In particular, the broadening of these states as a function of the binding energy in Bi2Se3 and Bi2Te2Se — the most extensively studied topological insulators, has been studied in detail. The revealed stepped structure of broadening allowed us to distinguish the contributions of elastic and inelastic interband scattering (surface–bulk) to the quasiparticle eigenenergy and to show that it is comparable with elastic intraband scattering.
Concentration maxima of the mobility of 2D electrons scattered by correlated impurity ions in thin doped layers
Authors: Mikheev V. M.
Published: January 2019

The concentration dependences of the mobility of 2D-electrons upon scattering by an equilibrium correlated distribution of impurity ions at fixed temperatures are theoretically studied in the example of the AlxGa1–xAs/GaAs heterostructure. It is shown that, in the case of significant correlations in the arrangement of impurity ions, the presence of the effect of “electron conduction inversion” leads to local maxima of the electron mobility.
Thermal expansion of organic superconductor α-(BEDT-TTF)2 NH4Hg(SCN)4
Authors: Dolbin A. V. , Khlistuck M. V. , Eselson V. B. , Gavrilko V. G. , Vinnikov N. A. , Basnukaeva R. M. , Konstantinov V. A. , Luchinskii K. R. , Nakazawa Y.
Published: January 2019

The temperature dependence of the linear thermal expansion coefficients (LTEC) of a single crystal of α-(BEDT-TTF)2NH4Hg(SCN)4 where BEDT-TTF is bis(ethylenedithio)tetrathiafulvalene was studied by the meth­od of precision capacitive dilatometry in the temperature range 2-250 K along the crystallographic direction b (per­pendicular to the crystal layers). Negative values of LTEC were found below 4 K. Probably it is due to charge fluc­tuations as the temperature approaches the temperature of transition to the superconducting state Tc. It has been suggested that the bends on temperature dependence of LTEC observed in the temperature range 25-45 K are relat­ed to order-disorder arrangement of NH4+ ions. Weak maximum of the LTEC, detected at a temperature of about 200-220 K, can be caused by the processes of charge redistribution and the associated intermolecular interaction fluctuations.
Time decay estimates for solutions of the Cauchy problem for the modified Kawahara equation
Authors: Naumkin P. I.
Published: January 2019

The large-time behaviour of solutions of the Cauchy problem for the modified Kawahara equationwhere, is investigated. Under the assumptions that the total mass of the initial datais nonzero and the initial dataare small in the norm ofit is proved that a global-in-time solution exists and estimates for its large-time decay are found.

Bibliography: 19 titles.
Admissible pairs vs Gieseker-Maruyama
Authors: Timofeeva N. V.
Published: January 2019

Morphisms between the moduli functor of admissible semistable pairs and the Gieseker-Maruyama moduli functor (of semistable coherent torsion-free sheaves) with the same Hilbert polynomial on the surface are constructed. It is shown that these functors are isomorphic, and the moduli scheme for semistable admissible pairs

is isomorphic to the Gieseker-Maruyama moduli scheme. All the components of moduli functors and corresponding moduli schemes which exist are looked at here.

Bibliography: 16 titles.
Effect of heat load and dietary protein on oxygen pulse and energy cost for locomotion in heifers
Authors: Valente E. E. L. , Filipini V. T. , Araújo L. C. , Stahlhofer M. , Melo B. V. R. , Bantle E. L. , Pilz D. F. , Arndt S. N. S. , Damasceno M. L. , Barbizan M.
Published: January 2019

The objectives of the present study were to evaluate the effect of heat load, bodyweight and dietary protein on oxygen pulse of heifers, to obtain the energy cost of walking on flat and sloping terrain, and to compare the energy cost of heifers during continuous walking and intermittent walking. In Experiment 1, the correlations of oxygen consumption, heart rate and oxygen pulse (O2P) with bodyweight, black globe temperature and temperature and humidity index were examined. Moreover, the effect of dietary protein on O2P was evaluated. The temperature and humidity index and black globe temperature had a low positive correlation with O2P and oxygen consumption, and a low negative correlation with heart rate. However, weight had no correlation with O2P. There was a linear increase in O2P with a very low adjustment with an increasing dietary crude protein concentration. In Experiment 2, the energy cost of heifers walking continuously at a constant speed in a terrain with 0%, 6% and 12% gradient was measured. The energy expenditure was similar among the terrain gradients. The heifers walking had a 16.6% higher energy expenditure than when they were standing. In Experiment 3, a comparison of the energy cost was made among heifers standing, continuously walking and intermittently walking at a constant speed on flat ground. The energy cost for walking was similar between continuous and intermittent walking. The heat load, bodyweight and dietary protein concentration had a low effect on O2P in dairy heifers. Therefore, measurements over a short time (5–15 min) are a reliable estimator of O2P through the day. Both intermittent and continuous walking can be used to evaluate energy expenditure.
Influence of Surfactant on the Phase Transformation of Bi2O3 and its Photocatalytic Activity
Authors: Karthik Kasinathan , Devi K. R. Sunaja , Pinheiro Dephan , Sugunan Sankaran
Published: January 2019

Bismuth oxide with its unique narrow bandgap has gained significant attention in the field of photocatalysis. A new and efficient method to synthesise bismuth oxide with tuneable properties is proposed herein. A surfactant assisted modified sol–gel method is used to synthesise bismuth oxide with excellent photocatalytic activity for the degradation of Rhodamine B dye. Three different surfactants, namely polyethylene glycol-400, sodium lauryl sulfate, and cetyltrimethylammonium bromide (CTAB) have been used. The fabricated bismuth oxide nanoparticles were characterised by X-ray diffraction, IR, scanning electron microscopy, and UV-diffuse reflectance spectroscopy analysis. Evolution of both the α and β crystalline phases of bismuth oxide was observed. The bandgap of the synthesised bismuth oxides ranges from 2.03 to 2.37eV. The CTAB assisted synthesised bismuth oxide with a bandgap of 2.19eV showed the highest photocatalytic activity of 93.6% under visible light for the degradation of Rhodamine B. This bismuth oxide based catalyst opens a new avenue for efficient photocatalysis for environmental remediation.
Efficacy of lethal-trap devices to improve the welfare of trapped wild dogs
Authors: Meek Paul D. , Brown Stuart C. , Wishart Jason , Milne Heath , Aylett Paul , Humphrys Simon , Ballard Guy , Fleming Peter
Published: January 2019

Context Wildlife and pest managers and stakeholders should constantly aim to improve animal-welfare outcomes when foot-hold trapping pest animals. To minimise stress and trauma to trapped animals, traps should be checked at least once every 24h, normally as soon after sunrise as possible. If distance, time, environmental or geographical constraints prevent this, toxins such as strychnine can be fitted to trap jaws to induce euthanasia. However, strychnine is considered to have undesirable animal-welfare outcomes because animals are conscious while clinical signs of intoxication are present. A toxin considered more humane, para-aminopropiophenone (PAPP), is available to induce euthanasia in trapped animals but is untested for presentation and efficacy. Aim We tested the efficacy of two types of lethal trap device (LTD’s), each using a paste formulation of PAPP as the active toxin to replace the use of strychnine on foot-hold jaw traps. Methods Elastomer LTDs and PAPP-cloths were fitted to jaw traps set to capture wild dogs (Canis familiaris). Camera-trap data was used to record animal behaviours after capture and to determine the efficacy of both modalities. Key results Every trapped wild dog (n=117) gnawed at the elastomer LTD’s or PAPP-cloth attached to the trap jaws that restrained them; one dog failed to liberate the toxin. From the dogs caught in the main trial (n=56), a mortality rate of 84% and 87% was reported respectively. The mean time from trap-to-death for elastomer LTDs was 64min and 68min for PAPP-cloths. Conclusions Elastomer LTDs and PAPP cloths combined caused the mortality of 85% of captured dogs. This efficacy could be improved by adopting the recommendations discussed in the present study for deploying PAPP-based LTDs during trap deployment. Implications PAPP-based LTDs offer an alternative option to the use of strychnine and improve the welfare outcomes for trapped predators, especially where traps are not checked within the recommended 24-h period.
Green fluorescence from cnidarian hosts attracts symbiotic algae
Authors: Aihara Yusuke , Maruyama Shinichiro , Baird Andrew H. , Iguchi Akira , Takahashi Shunichi , Minagawa Jun
Published: January 2019

Significance

Reef-building corals cannot survive without symbiotic algae,
Symbiodinium
, on which they depend for most of their energy. Most coral species gain symbionts from the environment early in life, and possibly after bleaching (i.e., the loss of symbionts in response to stress). However,
Symbiodinium
density on coral reefs is very low. Although it has long been hypothesized that corals must be able to attract free-living
Symbiodinium
, such a mechanism has yet to be identified. Here, we use a series of experiments to demonstrate that corals attract
Symbiodinium
using their endogenous GFP-related green fluorescence, revealing a biological signaling mechanism that underlies the success of this symbioses that is the building block of coral reef ecosystems.
Ice is born in low-mobility regions of supercooled liquid water
Authors: Fitzner Martin , Sosso Gabriele C. , Cox Stephen J. , Michaelides Angelos
Published: January 2019

Significance

From intracellular freezing to cloud formation, the crystallization of water is ubiquitous and shapes life as we know it. A full comprehension of the ice nucleation process at the molecular scale remains elusive and we cannot predict where nucleation will occur. Using computational techniques we show that homogeneous nucleation in supercooled water happens in immobile liquid regions that emerge from heterogeneous dynamics. With this we link the topics of nucleation and dynamical heterogeneity and open ways to understand and control heterogeneous nucleation in solution, in confinement, or at interfaces via understanding their effects on liquid dynamics.
Cul4 ubiquitin ligase cofactor DCAF12 promotes neurotransmitter release and homeostatic plasticity
Authors: Patrón Lilian A. , Nagatomo Kei , Eves David Tyler , Imad Mays , Young Kimberly , Torvund Meaghan , Guo Xiufang , Rogers Gregory C. , Zinsmaier Konrad E.
Published: January 2019

We genetically characterized the synaptic role of the Drosophila homologue of human DCAF12, a putative cofactor of Cullin4 (Cul4) ubiquitin ligase complexes. Deletion of Drosophila DCAF12 impairs larval locomotion and arrests development. At larval neuromuscular junctions (NMJs), DCAF12 is expressed presynaptically in synaptic boutons, axons, and nuclei of motor neurons. Postsynaptically, DCAF12 is expressed in muscle nuclei and facilitates Cul4-dependent ubiquitination. Genetic experiments identified several mechanistically independent functions of DCAF12 at larval NMJs. First, presynaptic DCAF12 promotes evoked neurotransmitter release. Second, postsynaptic DCAF12 negatively controls the synaptic levels of the glutamate receptor subunits GluRIIA, GluRIIC, and GluRIID. The down-regulation of synaptic GluRIIA subunits by nuclear DCAF12 requires Cul4. Third, presynaptic DCAF12 is required for the expression of synaptic homeostatic potentiation. We suggest that DCAF12 and Cul4 are critical for normal synaptic function and plasticity at larval NMJs.
Comparison of ion transport determinants between a TMEM16 chloride channel and phospholipid scramblase
Authors: Nguyen Dung M. , Chen Louisa S. , Yu Wei-Ping , Chen Tsung-Yu
Published: January 2019

Two TMEM16 family members, TMEM16A and TMEM16F, have different ion transport properties. Upon activation by intracellular Ca2+, TMEM16A—a Ca2+-activated Cl− channel—is more selective for anions than cations, whereas TMEM16F—a phospholipid scramblase—appears to transport both cations and anions. Under saturating Ca2+ conditions, the current–voltage (I-V) relationships of these two proteins also differ; the I-V curve of TMEM16A is linear, while that of TMEM16F is outwardly rectifying. We previously found that mutating a positively charged lysine residue (K584) in the ion transport pathway to glutamine converted the linear I-V curve of TMEM16A to an outwardly rectifying curve. Interestingly, the corresponding residue in the outwardly rectifying TMEM16F is also a glutamine (Q559). Here, we examine the ion transport functions of TMEM16 molecules and compare the roles of K584 of TMEM16A and Q559 of TMEM16F in controlling the rectification of their respective I-V curves. We find that rectification of TMEM16A is regulated electrostatically by the side-chain charge on the residue at position 584, whereas the charge on residue 559 in TMEM16F has little effect. Unexpectedly, mutation of Q559 to aromatic amino acid residues significantly alters outward rectification in TMEM16F. These same mutants show reduced Ca2+-induced current rundown (or desensitization) compared with wild-type TMEM16F. A mutant that removes the rundown of TMEM16F could facilitate the study of ion transport mechanisms in this phospholipid scramblase in the same way that a CLC-0 mutant in which inactivation (or closure of the slow gate) is suppressed was used in our previous studies.
Performance enhancement of a proposed solar cell microstructure based on heavily doped silicon wafers
Authors: Salem Marwa S , Zekry A , Shaker A , Abouelatta M , Abdolkader Tarek M
Published: January 2019

This paper aims to present a proposed npn solar cell microstructure based on low cost heavily doped Silicon wafers. The physical perception of the proposed structure is based on the idea of vertical generation and lateral collection of light generated carriers. It should be mentioned that our structure can be utilized whenever the diffusion length of photogenerated electron hole pairs is smaller than the penetration depth of the solar radiation. The enhancement in the structure performance is attained by the optimization of the structure technological and geometrical parameters and based on practical considerations. This enhancement enables achieving the maximum possible structure conversion efficiency. Moreover, the optical performance, in terms of the spectral response and external quantum efficiency, is presented. The optimization is carried out using SILVACO TCAD process and device simulators. The main parameters used in optimization include the thickness and doping of the top n
+ layer as well as the sidewall emitter. Additionally, the structure base width along with the notch depth are considered. Finally, back surface treatment is introduced. The structure conversion efficiency in the initial step before optimization was 10.7%. As a result of the optimization process, the structure conversion efficiency is improved to about 15% above the initial case study by 4%.
Are clusterings of multiple data views independent?
Authors: Gao Lucy L , Bien Jacob , Witten Daniela
Published: January 2019

In the Pioneer 100 (P100) Wellness Project, multiple types of data are collected on a single set of healthy participants at multiple timepoints in order to characterize and optimize wellness. One way to do this is to identify clusters, or subgroups, among the participants, and then to tailor personalized health recommendations to each subgroup. It is tempting to cluster the participants using all of the data types and timepoints, in order to fully exploit the available information. However, clustering the participants based on multiple data views implicitly assumes that a single underlying clustering of the participants is shared across all data views. If this assumption does not hold, then clustering the participants using multiple data views may lead to spurious results. In this article, we seek to evaluate the assumption that there is some underlying relationship among the clusterings from the different data views, by asking the question: are the clusters within each data view dependent or independent? We develop a new test for answering this question, which we then apply to clinical, proteomic, and metabolomic data, across two distinct timepoints, from the P100 study. We find that while the subgroups of the participants defined with respect to any single data type seem to be dependent across time, the clustering among the participants based on one data type (e.g. proteomic data) appears not to be associated with the clustering based on another data type (e.g. clinical data).
Gemykibivirus Genome in Lower Respiratory Tract of Elderly Woman With Unexplained Acute Respiratory Distress Syndrome
Authors: Wang Jian , Li Yanpeng , He Xi , Ma Jinmin , Hong Wenxin , Hu Fengyu , Zhao Lingzhai , Li Qiongfang , Zhang Jianhui , Zhang Chiyu , Zhang Fuchun
Published: January 2019

Using metagenomics analysis, we are the first to identify the presence of a small, circular, single-stranded Gemykibivirus (GkV) genome from the respiratory tract of an elderly woman with severe acute respiratory distress syndrome. Our results suggest that further studies on whether GkVs infect humans and cause respiratory disease are needed.
Normal values of aortic dimensions assessed by multidetector computed tomography in the Copenhagen General Population Study
Authors: Pham Michael H C , Ballegaard Christian , de Knegt Martina C , Sigvardsen Per E , Sørgaard Mathias H , Fuchs Andreas , Kühl Jørgen T , Taudorf Mikkel , Nordestgaard Børge G , Køber Lars V , Kofoed Klaus F
Published: January 2019

Aims

Accurate assessment of aortic dimensions can be achieved using contrast-enhanced computed tomography. The aim of this study was to define normal values and determinants of aortic dimensions throughout multiple key anatomical landmarks of the aorta in healthy individuals from the Copenhagen General Population Study.

Methods and results

The study group consisted of 902 healthy subjects selected from 3000 adults undergoing cardiovascular thoracic and abdominal computed tomography-angiography (CTA), where systematic measurements of aortic dimensions were performed retrospectively. Individuals included were without any of the following predefined cardiovascular risk factors: (i) self-reported angina pectoris; (ii) hypertension; (iii) hypercholesterolaemia; (iv) taking cardiovascular prescribed medication including diuretics, statins, or aspirin; (v) overweight (defined as body mass index ≥30 kg/m2); (vi) diabetes mellitus (self-reported or blood glucose >8 mmol/L); and (vii) chronic obstructive pulmonary disease. Maximal aortic diameters were measured at seven aortic regions: sinuses of Valsalva, sinotubular junction, ascending aorta, mid-descending aorta, abdominal aorta at the diaphragm, abdominal aorta at the coeliac trunk, and infrarenal abdominal aorta. Median age was 52 years, and 396 (40%) were men. Men had significantly larger aortic diameters at all levels compared with women (P < 0.001). Multivariable analysis revealed that sex, age, and body surface area were associated with increasing aortic dimensions.

Conclusion

Normal values of maximal aortic dimensions at key aortic anatomical locations by contrast-enhanced CTA have been defined. Age, sex, and body surface area were significantly associated with these measures at all levels of aorta. Aortic dimensions follow an almost identical pattern throughout the vessel regardless of sex.
Communication’s role in overcoming challenges for obesity prevention partnerships
Authors: Werder Olaf , Holland Kate , Munro Jay
Published: January 2019

With obesity rates growing worldwide calls have increased to coordinate efforts in nationwide partnership models. Yet, the necessity for professional partnerships has brought into sharper focus a problem in jointly communicating obesity and its prevention. Following a social representation framework and using episodic interviewing of members from different professions directly or indirectly involved in obesity prevention, this report critically analysed concepts and communicative approaches held by those professional areas. Key findings included different perspectives about communication orientations, namely distribution of responsibility, control and communication goals. This suggests that the profession-specific world-views prevented respondents from communicating with members from other professions. We conclude that health communication experts bring unique skills to bring together professional teams to not only develop a common language and conceptual framework but also facilitate a sense of inclusion and personal accomplishment.
TXS 0506+056, the first cosmic neutrino source, is not a BL Lac
Authors: Padovani P , Oikonomou F , Petropoulou M , Giommi P , Resconi E
Published: January 2019

We present evidence that TXS 0506+056, the first plausible non-stellar neutrino source, despite appearances, is not a blazar of the BL Lac type but is instead a masquerading BL Lac, i.e. intrinsically a flat-spectrum radio quasar with hidden broad lines and a standard accretion disc. This reclassification is based on: (1) its radio and $\rm {O \,{\small {II}}}$ luminosities; (2) its emission line ratios; (3) its Eddington ratio. We also point out that the synchrotron peak frequency of TXS 0506+056 is more than two orders of magnitude larger than expected by the so-called ‘blazar sequence’, a scenario which has been assumed by some theoretical models predicting neutrino (and cosmic ray) emission from blazars. Finally, we comment on the theoretical implications this reclassification has on the location of the γ-ray emitting region and our understanding of neutrino emission in blazars.
The Role of Homology and Orthology in the Phylogenomic Analysis of Metazoan Gene Content
Authors: Pett Walker , Adamski Marcin , Adamska Maja , Francis Warren R , Eitel Michael , Pisani Davide , Wörheide Gert
Published: January 2019

Resolving the relationships of animals (Metazoa) is crucial to our understanding of the origin of key traits such as muscles, guts, and nerves. However, a broadly accepted metazoan consensus phylogeny has yet to emerge. In part, this is because the genomes of deeply diverging and fast-evolving lineages may undergo significant gene turnover, reducing the number of orthologs shared with related phyla. This can limit the usefulness of traditional phylogenetic methods that rely on alignments of orthologous sequences. Phylogenetic analysis of gene content has the potential to circumvent this orthology requirement, with binary presence/absence of homologous gene families representing a source of phylogenetically informative characters. Applying binary substitution models to the gene content of 26 complete animal genomes, we demonstrate that patterns of gene conservation differ markedly depending on whether gene families are defined by orthology or homology, that is, whether paralogs are excluded or included. We conclude that the placement of some deeply diverging lineages may exceed the limit of resolution afforded by the current methods based on comparisons of orthologous protein sequences, and novel approaches are required to fully capture the evolutionary signal from genes within genomes.
What Triggers an LBP Flare? A Content Analysis of Individuals’ Perspectives
Authors: Costa Nathalia , Hodges Paul W , Ferreira Manuela L , Makovey Joanna , Setchell Jenny
Published: January 2019

Objective

For many, low back pain (LBP) is a lifelong condition with symptoms varying over time. Previous studies have investigated long-term risk factors and triggers for onset of LBP. No study has examined causes for less distinct fluctuations of symptoms, such as “flares,” which individuals with LBP identify as a significant and worrisome part of LBP. As little is known about what triggers this type of fluctuation, we aimed to investigate individuals’ perspectives on LBP flare triggers.

Methods

We conducted an online survey of 130 people with LBP, asking what they think triggers their flares. Data were qualitatively examined using content analysis.

Results

Most participants identified biomedical (84.8%) triggers, endorsing physical/biological factors to explain the flare occurrence. Themes included active movements (35% of participants), static postures (28.1%), overdoing a task (5.3%), biomechanical dysfunction (4.4%), comorbidities (4%), lack of exercise (3.3%), work (1.8%), and medications (1.5%). Nonbiomedical triggers were reported by 15.2% and included psychosocial and contextual factors, including psychological state (6%), weather (5%), sleep (2%), diet (1.2%), and fatigue (1%). These results indicate that individuals consider biomedical factors to be the main triggers of LBP flares, but some acknowledge nonbiomedical triggers.

Conclusions

Study findings contrast with current pain theories, which suggest that there is a need for a reduced emphasis on biomedical causes of LBP pain, especially when persistent. Recognition of patients’ views on causes of LBP flares is crucial to better guide clinical practice and inform further research. The validity of triggers identified by LBP patients requires further investigation.
Ecological specificity of the metagenome in a set of lower termite species supports contribution of the microbiome to adaptation of the host
Authors: Waidele Lena , Korb Judith , Voolstra Christian R , Dedeine Franck , Staubach Fabian
Published: January 2019

Background

Elucidating the interplay between hosts and their microbiomes in ecological adaptation has become a central theme in evolutionary biology. A textbook example of microbiome-mediated adaptation is the adaptation of lower termites to a wood-based diet, as they depend on their gut microbiome to digest wood. Lower termites have further adapted to different life types. Termites of the wood-dwelling life type never leave their nests and feed on a uniform diet. Termites of the foraging life type forage for food outside the nest and have access to other nutrients. Here we sought to investigate whether the microbiome that is involved in food substrate breakdown and nutrient acquisition might contribute to adaptation to these ecological differences. We reasoned that this should leave ecological imprints on the microbiome.

Results

We investigated the protist and bacterial microbiomes of a total of 29 replicate colonies from five termite species, covering both life types, using metagenomic shotgun sequencing. The microbiome of wood-dwelling species with a uniform wood diet was enriched for genes involved in lignocellulose degradation. Furthermore, metagenomic patterns suggest that the microbiome of wood-dwelling species relied primarily on direct fixation of atmospheric nitrogen, while the microbiome of foraging species entailed the necessary pathways to utilize nitrogen in the form of nitrate for example from soil.

Conclusion

Our findings are consistent with the notion that the microbiome of wood-dwelling species bears an imprint of its specialization on degrading a uniform wood diet, while the microbiome of the foraging species might reflect its adaption to access growth limiting nutrients from more diverse sources. This supports the idea that specific subsets of functions encoded by the microbiome can contribute to host adaptation.
Convergent inactivation of the skin-specific C-C motif chemokine ligand 27 in mammalian evolution
Authors: Lopes-Marques Monica , Alves Luis Q. , Fonseca Miguel , Secci-Petretto Giulia , Machado Andre M. , Ruivo Raquel , Castro Filipe
Published: January 2019

The appearance of mammalian-specific skin features was a key evolutionary event contributing for the elaboration of physiological processes such as thermoregulation, adequate hydration, locomotion and inflammation. Skin inflammatory and autoimmune processes engage a population of skin-infiltrating T cells expressing a specific C-C chemokine receptor (CCR10), which interacts with an epidermal CC chemokine, the skin-specific C-C motif chemokine ligand 27 (CCL27). CCL27 is selectively produced in the skin by keratinocytes, particularly upon inflammation, mediating the adhesion and homing of skin-infiltrating T cells. Here, we examined the evolution and coding condition of Ccl27 in 112 placental mammalian species. Our findings reveal that a number of open reading frame inactivation events such as insertions, deletions, start and stop codon mutations, independently occurred in Cetacea, Pholidota, Sirenia, Chiroptera, and Rodentia, totalizing 18 species. The diverse habitat settings and life-styles of Ccl27-eroded lineages probably implied distinct evolutionary triggers rendering this gene unessential. For example, in Cetacea the rapid renewal of skin layers minimizes the need for an elaborate inflammatory mechanism, mirrored by the absence of epidermal scabs. Our findings suggest that the convergent and independent loss of Ccl27 in mammalian evolution concurred with unique adaptive roads for skin physiology.
Association between premorbid body mass index and amyotrophic lateral sclerosis: causal inference through genetic approaches
Authors: Zeng Ping , Yu Xinghao , Xu Haibo
Published: January 2019

Background: Inverse association between premorbid body mass index (BMI) and amyotrophic lateral sclerosis (ALS) has been discovered in observational studies; however, whether this association is causal remains largely unknown.
Methods: We employed a two-sample Mendelian randomization approach to evaluate the causal relationship of genetically increased BMI with the risk of ALS. The analyses were implemented using summary statistics obtained for the independent instruments identified from large-scale genome-wide association studies of BMI (up to ~770,000 individuals) and ALS (up to ~81,000 individuals). The causal relationship between BMI and ALS was estimated using inverse-variance weighted methods and was further validated through extensive complementary and sensitivity analyses.
Findings: Using 1,031 instruments strongly related to BMI, the causal effect of per one standard deviation increase of BMI was estimated to be 1.04 (95% CI 0.97~1.11, p=0.275) in the European population. The null association between BMI and ALS discovered in the European population also held in the East Asian population and was robust against various modeling assumptions and outlier biases. Additionally, the Egger-regression and MR-PRESSO ruled out the possibility of horizontal pleiotropic effects of instruments.
Interpretation: Our results do not support the causal role of genetically increased or decreased BMI on the risk of ALS.
Platelet-neutrophil aggregates promote skin pathology in psoriasis
Authors: Herster Franziska , Bittner Zsofia , Cordrea Marius Cosmin , Archer Nate , Heister Martin , Löffler Markus W. , Heumos Simon , Wegner Joanna , Businger Ramona , Schindler Michael , Stegner David , Schäkel Knut , Grabbe Stephan , Ghoreschi Kamran , Miller Lloyd , Weber Alexander N.R.
Published: January 2019

Psoriasis is a frequent systemic inflammatory autoimmune disease characterized primarily by skin lesions with massive infiltration of leukocytes but frequently also presents with cardiovascular comorbidities. Especially polymorphonuclear neutrophils (PMNs) abundantly infiltrate psoriatic skin but the cues that prompt PMNs to home to the skin are not well defined. To identify PMN surface receptors that may explain PMN skin homing in psoriasis patients, we screened 332 surface antigens on primary human blood PMNs from healthy donors and psoriasis patients. We identified platelet surface antigens as a defining feature of psoriasis PMNs, due to a significantly increased aggregation of neutrophils and platelets in the blood of psoriasis patients. Similarly, in the imiquimod-induced experimental in vivo model of psoriasis, disease induction promoted PMN-platelet aggregate formation. In psoriasis patients, disease directly correlated with blood platelet counts and platelets were detected in direct contact with PMNs in psoriatic but not healthy skin. Importantly, depletion of circulating platelets in vivo ameliorated disease severity significantly, indicating that the intimate relationship of PMNs and platelets may be relevant for psoriasis pathology and disease severity, and potentially for psoriasis-associated cardiovascular comorbidities.

Key points

Human neutrophils in psoriasis patient blood show a distinct ‘platelet signature’ of surface antigens

Platelets congregate with neutrophils in psoriatic skin lesions

Circulating platelets contribute to psoriasis skin pathology