bluuebunny/crossref_metadata_2025 huggingface dataset:
A Portuguese exception to right-wing populism
Authors: Quintas da Silva Rodrigo
Published: January 2018

Many European countries have witnessed the rise of right-wing (nativist and authoritarian) populist parties over the last few years, which have gained significant votes and sometimes threatened the position of traditional parties. In Portugal, however, right-wing populism has failed to gain electoral support, and the populist discourse is scarcely found in Portuguese politics. In this comment, we offer four tentative hypotheses that explain why right-wing parties with a populist discourse are not present in Portugal: low levels of Eurospecticism, low immigration rates, lack of political space to develop, and lower engagement in communicating that same populism. We conclude that these dynamics create a special balance, and a rather specific political situation in Portugal that does not facilitate the spread of right-wing populism. This balance, we also argue, may be compromised if any of these dynamics suddenly change, potentially paving the way for right-wing populists in Portugal to achieve more political prominence.
Bi-layer plate-type acoustic metamaterials with Willis coupling
Authors: Ma Fuyin , Huang Meng , Xu Yicai , Wu Jiu Hui
Published: January 2018

Dynamic effective negative parameters are principal to the representation of the physical properties of metamaterials. In this paper, a bi-layer plate-type unit was proposed with both a negative mass density and a negative bulk modulus; moreover, through analysis of these bi-layer structures, some important problems about acoustic metamaterials were studied. First, dynamic effective mass densities and the bulk modulus of the bi-layer plate-type acoustic structure were clarified through both the direct and the retrieval methods, and, in addition, the intrinsic relationship between the sound transmission (absorption) characteristics and the effective parameters was analyzed. Furthermore, the properties of dynamic effective parameters for an asymmetric bi-layer acoustic structure were further considered through an analysis of experimental data, and the modified effective parameters were then obtained through consideration of the Willis coupling in the asymmetric passive system. In addition, by taking both the clamped and the periodic boundary conditions into consideration in the bi-layer plate-type acoustic system, new perspectives were presented for study on the effective parameters and sound insulation properties in the range below the cut-off frequency. The special acoustic properties established by these effective parameters could enrich our knowledge and provide guidance for the design and installation of acoustic metamaterial structures in future sound engineering practice.
Dispersion relation of quasi-static electromagnetic modes in relativistic plasmas
Authors: Medjkoune Y. C. , Bendib-Kalache K. , Bendib A.
Published: January 2018

Transverse quasi-static electromagnetic modes (ωkc≪1 , where ω and k are the mode frequency and the wavenumber, respectively, and c is the speed of light) are studied in laser heated relativistic plasmas, where the electron thermal energy could be comparable to or greater than the electron rest mass energy. A dispersion relation of these modes valid in the whole collisionality regime is derived with the use of the relativistic Vlasov-Landau and Maxwell equations. The dissipative part of the dispersion relation is calculated with the Maxwell-Boltzmann-Jüttner distribution function, as a function of the Knudsen number kλei, where λei is the electron mean-free-path. It is shown that the dissipative part exhibits a continuous transition from the collisional regime [∼kλei2] to the Landau collisionless one [∼kλei3]. The relativistic electrical conductivity is also deduced and compared with the results reported in the literature. Taking into account the anisotropy of the distribution function induced by the inverse bremsstrahlung absorption, the stability analysis of the electromagnetic modes is presented. It is found that for typical inertial confinement fusion plasmas, strong growing modes could be driven.
Spin injection in epitaxial MnGa(111)/GaN(0001) heterostructures
Authors: Zube Christian , Malindretos Joerg , Watschke Lars , Zamani Reza R. , Disterheft David , Ulbrich Rainer G. , Rizzi Angela , Iza Michael , Keller Stacia , DenBaars Steven P.
Published: January 2018

Ferromagnetic MnGa(111) layers were grown on GaN(0001) by molecular beam epitaxy. MnGa/GaN Schottky diodes with a doping level of around n = 7 × 1018 cm−3 were fabricated to achieve single step tunneling across the metal/semiconductor junction. Below the GaN layer, a thin InGaN quantum well served as optical spin detector (“spin-LED”). For electron spin injection from MnGa into GaN and subsequent spin transport through a 45 nm (70 nm) thick GaN layer, we observe a circular polarization of 0.3% (0.2%) in the electroluminescence at 80 K. Interface mixing, spin polarization losses during electrical transport in the GaN layer, and spin relaxation in the InGaN quantum well are discussed in relation with the low value of the optically detected spin polarization.
Universal aspects of sonolubrication in amorphous and crystalline materials
Authors: Pfahl V. , Ma C. , Arnold W. , Samwer K.
Published: January 2018

We studied sonolubricity, a phenomenon reducing the friction between two sliding surfaces by ultrasound. Friction force measurements were performed using an atomic force microscope (AFM) when the tip-surface contact was excited to out-of-plane oscillations by a transducer attached to the rear of the sample or by oscillating the AFM cantilever by the built-in piezoelectric element in the cantilever holder. Experiments were carried out near or at the first cantilever contact-resonance. We studied friction on crystalline and amorphous Pd77.5Cu6Si16.5 ribbons, on a silicon wafer at room temperature, and on a La0.6Sr0.4MnO3 (LSMO) thin film at different temperatures. Measurements were carried out varying the cantilever amplitude, the ultrasonic frequency, and the normal static load. The effect of sonolubrication is explained by the non-linear force-distance curve between the sample and the tip due to the local interaction potential. The reduction of friction in LSMO as a function temperature is due to the direct coupling of the tip's stress-field to the electrons.
Piezoresponse force and electrochemical strain microscopy in dual AC resonance tracking mode: Analysis of tracking errors
Authors: Bradler Stephan , Schirmeisen André , Roling Bernhard
Published: January 2018

Contact-resonance atomic force microscopy allows the quantitative mapping of local viscoelastic and electromechanical properties. Excitation and amplification are generally described by the damped harmonic oscillator (DHO) model. The dual AC resonance tracking technique measures the amplitude and phase at two probing frequencies close to the resonance frequency and calculates the parameters of the DHO model from the amplitudes and phases. However, real systems show contact-resonance curves with slight deviations from the DHO model. In this work, we analyze how these deviations influence the obtained DHO parameters. We show that for a piezoelectric sample and for a mixed ion-electron conducting sample, the drive amplitude increases with increasing tracking error, while the opposite is observed for the amplification factor. Thus, in electrochemical strain microscopy experiments, the influence of the tracking error on the DHO parameters can be analyzed by calculating a tracking error image and studying correlations with the DHO parameter images.
Prediction the concentration of graphite direct exfoliation by liquid solution with solubility parameters map
Authors: Liang Ko-Yuan , Yang Wein-Duo
Published: January 2018

This study is to discuss solvent selection with graphene dispersion concentration of directly exfoliation graphite. That limiting boundaries of fractional cohesion parameters will be draw on the triangular diagram to prediction and estimate. It is based on the literature of data and check with experimental or other literature results, include organic solution, aqueous solution and ionic liquid. In this work, we found that estimated the graphene dispersion concentration by distance (Ra) of Hansen solubility parameters (HSP) between graphene and solvent, the lower Ra; the higher concentration, some case the lower Ra; the lower dispersion concentration (such as acetone). It is compatible with the graphene dispersion concentration on the Hansen space or Triangular fractional cohesion parameters dispersion diagram. From Triangular fractional cohesion parameters dispersion diagram, 2D maps are more convenient for researchers than 3D maps of Hansen space and quickly to find the appropriate combination of solvents for different application.
Quenching of exciton luminescence in SrF2 nanoparticles within a diffusion model
Authors: Chylii M. , Demkiv T. , Vistovskyy V. , Malyi T. , Vasil'ev A. , Voloshinovskii A.
Published: January 2018

Quenching processes of the self-trapped exciton luminescence were studied analyzing the shape of X-ray luminescence decay kinetics curves of SrF2 nanoparticles of different sizes. To describe the curves of luminescence decay kinetics, an equation was obtained which is based on the model which takes into account the diffusion of self-trapped excitons and which considers the case of strong surface quenching. The obtained relation was shown to describe the shape of the experimental curves of X-ray luminescence decay kinetics of SrF2 nanoparticles if their size distribution is bi-modal, i.e., a log-normal distribution about a mean size in the tens of nanometers range plus a distribution of particles larger than 130 nm. The presence of large particles is implied in this model by the single-exponential decay with time constant of 1.2 μs. From the fitting of kinetics curves using the proposed relation, the average diffusion length of self-trapped excitons in SrF2 was estimated to be (15 ± 2) nm.
CH3NH3Pb1−xMgxI3 perovskites as environmentally friendly photovoltaic materials
Authors: Zhang Y. D. , Feng J.
Published: January 2018

In an effort to reduce the toxicity of Pb in perovskite solar cells, the band structures, electron and hole effective masses, and electronic and optical properties of the novel perovskites CH3NH3Pb1−xMgxI3 were predicted using density functional theory with the scalar relativistic generalized gradient approximation. The calculation results indicated that the introduction of the Mg component caused the band gaps of the CH3NH3Pb1−xMgxI3 compounds to exceed that of CH3NH3PbI3. The calculated absorption coefficients of the CH3NH3PbI3 and CH3NH3Pb1−xMgxI3 perovskites revealed that substituting 12.5 mol % of the Pb in CH3NH3PbI3 with Mg had little effect on the absorption ability. Surprisingly, it was also found that CH3NH3Pb0.75Mg0.25I3 retained up to 83% of the absorption performance relative to CH3NH3PbI3. This indicates that the amount of toxic Pb used in perovskite solar cells could be reduced by a quarter while retaining over 80% of the light-absorbing ability. In general, these novel CH3NH3Pb1−xMgxI3 (x ≤ 0.25) perovskites represent promising candidates for environmentally friendly light-harvesting materials for use in solar cells.
Investigation of magnetization dynamics damping in Ni80Fe20/Nd-Cu bilayer at room temperature
Authors: Fan Wei , Fu Qiang , Qian Qian , Chen Qian , Liu Wanling , Zhou Xiaochao , Yuan Honglei , Yue Jinjin , Huang Zhaocong , Jiang Sheng , Kou Zhaoxia , Zhai Ya
Published: January 2018

Focusing on the Ni80Fe20 (Py)/Nd-Cu bilayers, the magnetization dynamic damping from spin pumping effect is investigated systematically by doping itinerant Cu in rear earth metal Nd. Various Ta/Py/Nd1-xCux/Ta/Si films with x = 0%, 16%, 38%, 46% and 58% are prepared by magnetron sputtering. For every content of Cu, the thickness of Nd-Cu layer is changed from 1 nm to 32 nm. The damping coefficient increases with increasing the thickness of Nd-Cu layer, which shows the trend of the spin pumping behavior. Also, with increasing Cu concentration in the Nd-Cu layer, the damping coefficient decreases, implying that the spin-orbit coupling in Nd-Cu layer is indeed cut down by high itinerant of Cu dopants. It is interesting that the spin diffusion length (λSD) in the Nd-Cu layer for different Cu dopants is not found to increase monotonously.
Magnetostrictive energy generator for harvesting the rotation of human knee joint
Authors: Yan Baiping , Zhang Chengming , Li Liyi
Published: January 2018

This paper presents the design and fabrication of a rotary-impact magnetostrictive energy generator, used to harvest the rotation of human knee joint. The harvester consists of twelve movable Terfenol-D rods, surrounded by the picked up coils respectively, and alternate permanent magnet (PM) array sandwiched in each part of the shell. Rotational electromagnetic power generating effect and impacted magnetostrictive power generating effect are designed in the harvester. Modeling and simulation are used to validate the concept. Then, magnetic field and leakage of the harvester are analyzed, electromagnetic force in the harvester is simulated. A prototype of harvester is fabricated, and subjected to the experimental characterization. It can be concluded that huge induced voltage generated in the short-time impact situation and that induced voltage in the harvester can reach up to 60-80 volts at 0.91Hz low frequency rotation. Also, the presented harvester has good harvesting effects at low frequency human walking and periodic swing crus situation, which are suitable to be used for future researches of wearable knee joint applications.
Iron-rich (Fe1-x-yNixCoy)88Zr7B4Cu1 nanocrystalline magnetic materials for high temperature applications with minimal magnetostriction
Authors: Martone Anthony , Dong Bowen , Lan Song , Willard Matthew A.
Published: January 2018

As inductor technology advances, greater efficiency and smaller components demand new core materials. With recent developments of nanocrystalline magnetic materials, soft magnetic properties of these cores can be greatly improved. FeCo-based nanocrystalline magnetic alloys have resulted in good soft magnetic properties and high Curie temperatures; however, magnetoelastic anisotropies persist as a main source of losses. This investigation focuses on the design of a new Fe-based (Fe,Ni,Co)88Zr7B4Cu1 alloy with reduced magnetostriction and potential for operation at elevated temperatures. The alloys have been processed by arc melting, melt spinning, and annealing in a protective atmosphere to produce nanocrystalline ribbons. These ribbons have been analyzed for structure, hysteresis, and magnetostriction using X-Ray diffraction, vibrating sample magnetometry (VSM), and a home-built magnetostriction system, respectively. In addition, Curie temperatures of the amorphous phase were analyzed to determine the best performing, high-temperature material. Our best result was found for a Fe77Ni8.25Co2.75Zr7B4Cu1 alloy with a 12 nm average crystallite size (determined from Scherrer broadening) and a 2.873 Å lattice parameter determined from the Nelson-Riley function. This nanocrystalline alloy possesses a coercivity of 10 A/m, magnetostrictive coefficient of 4.8 ppm, and amorphous phase Curie temperature of 218°C.
Rotating magnetizations in electrical machines: Measurements and modeling
Authors: Thul Andreas , Steentjes Simon , Schauerte Benedikt , Klimczyk Piotr , Denke Patrick , Hameyer Kay
Published: January 2018

This paper studies the magnetization process in electrical steel sheets for rotational magnetizations as they occur in the magnetic circuit of electrical machines. A four-pole rotational single sheet tester is used to generate the rotating magnetic flux inside the sample. A field-oriented control scheme is implemented to improve the control performance. The magnetization process of different non-oriented materials is analyzed and compared.
Magnetic phase change in Mn-doped ZnSnAs2 thin films depending on Mn concentration
Authors: Uchitomi Naotaka , Hidaka Shiro , Saito Shin , Asubar Joel T. , Toyota Hideyuki
Published: January 2018

The relationship between Mn concentration and Curie temperature (TC) is studied for Mn-doped ZnSnAs2 ferromagnetic semiconductors, epitaxially grown on InP substrates by molecular beam epitaxy. In the ferromagnetic phase, Mn distributions in a (Zn,Mn,Sn)As2 thin film with 7.2 cation percent (cat. %) Mn are investigated using three-dimensional atom probe tomography. The results indicate an inhomogeneous distribution which spreads to a relatively high Mn concentration of 9.0 at. % (at. %). In the paramagnetic phase, it is found that the paramagnetic to ferromagnetic transition takes place sharply with a TC of 334 K when the Mn doping concentration increases to about 4 cat. % Mn, which corresponds to a magnetic percolation threshold for ferromagnetism in (Zn,Mn,Sn)As2. An effective Curie temperature ⟨TC⟩ is considered to bridge the Curie temperatures obtained experimentally to those calculated theoretically in inhomogeneous magnetic semiconductors. The behavior of magnetism in Mn-doped ZnSnAs2 can be explained by three different phases within the present framework.
Hydrogen collisions with transition metal surfaces: Universal electronically nonadiabatic adsorption
Authors: Dorenkamp Yvonne , Jiang Hongyan , Köckert Hansjochen , Hertl Nils , Kammler Marvin , Janke Svenja M. , Kandratsenka Alexander , Wodtke Alec M. , Bünermann Oliver
Published: January 2018

Inelastic scattering of H and D atoms from the (111) surfaces of six fcc transition metals (Au, Pt, Ag, Pd, Cu, and Ni) was investigated, and in each case, excitation of electron-hole pairs dominates the inelasticity. The results are very similar for all six metals. Differences in the average kinetic energy losses between metals can mainly be attributed to different efficiencies in the coupling to phonons due to the different masses of the metal atoms. The experimental observations can be reproduced by molecular dynamics simulations based on full-dimensional potential energy surfaces and including electronic excitations by using electronic friction in the local density friction approximation. The determining factors for the energy loss are the electron density at the surface, which is similar for all six metals, and the mass ratio between the impinging atoms and the surface atoms. Details of the electronic structure of the metal do not play a significant role. The experimentally validated simulations are used to explore sticking over a wide range of incidence conditions. We find that the sticking probability increases for H and D collisions near normal incidence—consistent with a previously reported penetration-resurfacing mechanism. The sticking probability for H or D on any of these metals may be represented as a simple function of the incidence energy, Ein, metal atom mass, M, and incidence angle, 𝜗in. S=(S0+a⋅Ein+b⋅M)*(1−h(𝜗in−c)(1−cos(𝜗in−c)d⋅h(Ein−e)(Ein−e))), where h is the Heaviside step function and for H, S0 = 1.081, a = −0.125 eV−1, b=−8.40⋅10−4 u−1, c = 28.88°, d = 1.166 eV−1, and e = 0.442 eV; whereas for D, S0 = 1.120, a = −0.124 eV−1, b=−1.20⋅10−3 u−1, c = 28.62°, d = 1.196 eV−1, and e = 0.474 eV.
On the feasibility of p-type Ga2O3
Authors: Kyrtsos Alexandros , Matsubara Masahiko , Bellotti Enrico
Published: January 2018

We investigate the various cation substitutional dopants in Ga2O3 for the possibility of p–type conductivity using density functional theory. Our calculations include both standard density functional theory and hybrid functional calculations. We demonstrate that all the investigated dopants result in deep acceptor levels, not able to contribute to the p–type conductivity of Ga2O3. In light of these results, we compare our findings with other wide bandgap oxides and reexamine previous experiments on zinc doping in Ga2O3.
An investigation into the effective surface passivation of quantum dots by a photo-assisted chemical method
Authors: Joo So-Yeong , Park Hyun-Su , Kim Do-yeon , Kim Bum-Sung , Lee Chan Gi , Kim Woo-Byoung
Published: January 2018

In this study, we have developed an effective amino passivation process for quantum dots (QDs) at room temperature and have investigated a passivation mechanism using a photo-assisted chemical method. As a result of the reverse reaction of the H2O molecules, the etching kinetics of the photo-assisted chemical method increased upon increasing the 3-amino-1-propanol (APOL)/H2O ratio of the etching solution. Photon-excited electron-hole pairs lead to strong bonding between the organic and surface atoms of the QDs, and results in an increase of the quantum yield (QY%). This passivation method is also applicable to CdSe/ZnSe core/shell structures of QDs, due to the passivation of mid-gap defects states at the interface. The QY% of the as-synthesized CdSe QDs is dramatically enhanced by the amino passivation from 37% to 75% and the QY% of the CdSe/ZnSe core/shell QDs is also improved by ∼28%.
Blocking of deuterium diffusion in poly-Si/Al2O3/HfxSi1−xO2/SiO2 high-k stacks as evidenced by atom probe tomography
Authors: Tu Y. , Han B. , Shimizu Y. , Kunimune Y. , Shimada Y. , Katayama T. , Ide T. , Inoue M. , Yano F. , Inoue K. , Nagai Y.
Published: January 2018

Hydrogen (H) plays an important role in determining the reliability and performance of HfO2- and Al2O3-based high-k dielectric electronic devices. In order to understand H behavior, deuterium (D), an isotope of H, was introduced into the poly-Si cap of Al2O3/HfxSi1−xO2/SiO2 high-k stacks by ion implantation. Atom probe tomography was used to image the D distribution in samples annealed under different conditions. The results clearly demonstrated that the D atoms were trapped at the interface of poly-Si and Al2O3 after annealing at 900 K for 10 min. Thus, it is possible that Al2O3 blocks the H atoms at the surface, preventing them from diffusing into the high-k dielectrics during the H2 annealing process in current fabrication technology. The current work also exhibits an example of investigating H behavior in semiconductors by atom probe tomography.
The underlying micro-mechanism of performance enhancement of non-polar n-ZnO/p-AlGaN ultraviolet light emitting diode with i-ZnO inserted layer
Authors: Jiang Fan , Chen Jingwen , Bi Han , Li Luying , Jing Wenkui , Zhang Jun , Dai Jiangnan , Che Renchao , Chen Changqing , Gao Yihua
Published: January 2018

Non-polar a-plane n-ZnO/p-AlGaN and n-ZnO/i-ZnO/p-AlGaN heterojunction film light-emitting diodes (LEDs) are fabricated with good crystalline quality. The optical measurements show obvious performance enhancement with i-ZnO layer insertion. Off-axis electron holography reveals a potential drop of ∼1.5 V across the heterojunctions with typical p-n junction characteristics. It is found that the electrostatic potentials are inclined and the corresponding electrostatic fields are opposite to each other in n-ZnO and p-AlGaN regions. The electrostatic fields are mainly attributed to strain induced piezoelectric polarizations. After an insertion of an i-ZnO layer into the p-n heterojunction, comparatively flat electrostatic potential generates in the intrinsic ZnO region and contributes to faster movements of the injected electrons and holes, making the i-ZnO layer more conductive to the radiative recombination with enhanced exciton recombination possibilities and at last the LED performance enhancement.
Analysis of the anomalous mean-field like properties of Gaussian core model in terms of entropy
Authors: Nandi Manoj Kumar , Maitra Bhattacharyya Sarika
Published: January 2018

Studies of the Gaussian core model (GCM) have shown that it behaves like a mean-field model and the properties are quite different from standard glass former. In this work, we investigate the entropies, namely, the excess entropy (Sex) and the configurational entropy (Sc) and their different components to address these anomalies. Our study corroborates most of the earlier observations and also sheds new light on the high and low temperature dynamics. We find that unlike in standard glass former where high temperature dynamics is dominated by two-body correlation and low temperature by many-body correlations, in the GCM both high and low temperature dynamics are dominated by many-body correlations. We also find that the many-body entropy which is usually positive at low temperatures and is associated with activated dynamics is negative in the GCM suggesting suppression of activation. Interestingly despite the suppression of activation, the Adam-Gibbs (AG) relation that describes activated dynamics holds in the GCM, thus suggesting a non-activated contribution in AG relation. We also find an overlap between the AG relation and mode coupling power law regime leading to a power law behavior of Sc. From our analysis of this power law behavior, we predict that in the GCM the high temperature dynamics will disappear at dynamical transition temperature and below that there will be a transition to the activated regime. Our study further reveals that the activated regime in the GCM is quite narrow.
Jet behaviors and ejection mode recognition of electrohydrodynamic direct-write
Authors: Zheng Jianyi , Zhang Kai , Jiang Jiaxin , Wang Xiang , Li Wenwang , Liu Yifang , Liu Juan , Zheng Gaofeng
Published: January 2018

By introducing image recognition and micro-current testing, jet behavior research was conducted, in which the real-time recognition of ejection mode was realized. To study the factors influencing ejection modes and the current variation trends under different modes, an Electrohydrodynamic Direct-Write (EDW) system with functions of current detection and ejection mode recognition was firstly built. Then a program was developed to recognize the jet modes. As the voltage applied to the metal tip increased, four jet ejection modes in EDW occurred: droplet ejection mode, Taylor cone ejection mode, retractive ejection mode and forked ejection mode. In this work, the corresponding relationship between the ejection modes and the effect on fiber deposition as well as current was studied. The real-time identification of ejection mode and detection of electrospinning current was realized. The results in this paper are contributed to enhancing the ejection stability, providing a good technical basis to produce continuous uniform nanofibers controllably.
Prediction of large gap flat Chern band in a two-dimensional metal-organic framework
Authors: Su Ninghai , Jiang Wei , Wang Zhengfei , Liu Feng
Published: January 2018

Systems with a flat Chern band have been extensively studied for their potential to realize high-temperature fractional quantum Hall states. To experimentally observe the quantum transport properties, a sizable topological gap is highly necessary. Here, taking advantage of the high tunability of two-dimensional (2D) metal-organic frameworks (MOFs), whose crystal structures can be easily tuned using different metal atoms and molecular ligands, we propose a design of a 2D MOF [Tl2(C6H4)3, Tl2Ph3] showing nontrivial topological states with an extremely large gap in both the nearly flat Chern band and the Dirac bands. By coordinating π-conjugated thallium ions and benzene rings, crystalline Tl2Ph3 can be formed with Tl and Ph constructing honeycomb and kagome lattices, respectively. The px,y orbitals of Tl on the honeycomb lattice form ideal pxy four-bands, through which a flat Chern band with a spin-orbit coupling (SOC) gap around 140 meV evolves below the Fermi level. This is the largest SOC gap among all the theoretically proposed organic topological insulators so far.
Transitions between patterned discharges and diffuse discharges in atmospheric helium under applied voltages far below the discharge inception voltage
Authors: Hao Yanpeng , Han Yuying , Huang Zhiming , Yang Lin , Dai Dong , Li Licheng
Published: January 2018

A diffuse glow discharge was generated in atmospheric helium with a background air pressure of 40 Pa. When the applied voltage was slowly decreased to lower ones than the discharge inception voltage, the diffuse discharge showed transitions to a patterned one with a central column, then a patterned one with double circles, including one central column and seven or eight nearby columns in a circle, followed by a pattern with three circles, and finally a partial diffuse discharge under an applied voltage of about 66% of the discharge inception voltage.
Injection angle plays a major role in swirl flow dynamics
Authors: Majors J. H.
Published: January 2018

Numeric analysis of flow in a cylindrical chamber reveals an important relationship between injection angle and swirl flow characteristics, indicating predictable behavior.
Solution structure of sperm lysin yields novel insights into molecular dynamics of rapid protein evolution
Authors: Wilburn Damien B. , Tuttle Lisa M. , Klevit Rachel E. , Swanson Willie J.
Published: January 2018

Protein evolution is driven by the sum of different physiochemical and genetic processes that usually results in strong purifying selection to maintain biochemical functions. However, proteins that are part of systems under arms race dynamics often evolve at unparalleled rates that can produce atypical biochemical properties. In the marine mollusk abalone, lysin and vitelline envelope receptor for lysin (VERL) are a pair of rapidly coevolving proteins that are essential for species-specific interactions between sperm and egg. Despite extensive biochemical characterization of lysin—including crystal structures of multiple orthologs—it was unclear how sites under positive selection may facilitate recognition of VERL. Using a combination of targeted mutagenesis and multidimensional NMR, we present a high-definition solution structure of sperm lysin from red abalone (
Haliotis rufescens
). Unapparent from the crystallography data, multiple NMR-based analyses conducted in solution reveal clustering of the N and C termini to form a nexus of 13 positively selected sites that constitute a VERL binding interface. Evolutionary rate was found to be a significant predictor of backbone flexibility, which may be critical for lysin bioactivity and/or accelerated evolution. Flexible, rapidly evolving segments that constitute the VERL binding interface were also the most distorted regions of the crystal structure relative to what was observed in solution. While lysin has been the subject of extensive biochemical and evolutionary analyses for more than 30 years, this study highlights the enhanced insights gained from applying NMR approaches to rapidly evolving proteins.
Learning to make external sensory stimulus predictions using internal correlations in populations of neurons
Authors: Sederberg Audrey J. , MacLean Jason N. , Palmer Stephanie E.
Published: January 2018

To compensate for sensory processing delays, the visual system must make predictions to ensure timely and appropriate behaviors. Recent work has found predictive information about the stimulus in neural populations early in vision processing, starting in the retina. However, to utilize this information, cells downstream must be able to read out the predictive information from the spiking activity of retinal ganglion cells. Here we investigate whether a downstream cell could learn efficient encoding of predictive information in its inputs from the correlations in the inputs themselves, in the absence of other instructive signals. We simulate learning driven by spiking activity recorded in salamander retina. We model a downstream cell as a binary neuron receiving a small group of weighted inputs and quantify the predictive information between activity in the binary neuron and future input. Input weights change according to spike timing–dependent learning rules during a training period. We characterize the readouts learned under spike timing–dependent synaptic update rules, finding that although the fixed points of learning dynamics are not associated with absolute optimal readouts they convey nearly all of the information conveyed by the optimal readout. Moreover, we find that learned perceptrons transmit position and velocity information of a moving-bar stimulus nearly as efficiently as optimal perceptrons. We conclude that predictive information is, in principle, readable from the perspective of downstream neurons in the absence of other inputs. This suggests an important role for feedforward prediction in sensory encoding.
Tumor suppressor APC is an attenuator of spindle-pulling forces during
C. elegans
asymmetric cell division
Authors: Sugioka Kenji , Fielmich Lars-Eric , Mizumoto Kota , Bowerman Bruce , van den Heuvel Sander , Kimura Akatsuki , Sawa Hitoshi
Published: January 2018

Significance

Adenomatous polyposis coli (APC) is a Wnt signaling component as well as a microtubule-associated protein, and its mutations are frequently associated with colorectal cancers in humans. Although APC stabilizes microtubules, its mechanical role during cell division is largely unknown. Here we show that APC is an attenuator of forces acting on the mitotic spindle during asymmetric cell division of the
Caenorhabditis elegans
zygote. We performed live imaging, laser microsurgery, and numerical simulation to show how APC suppresses spindle-pulling force generation by stabilizing microtubule plus-ends and reducing microtubule catastrophe frequency at the cell cortex. Our study documents a mechanical role for the APC protein and provides a physical basis for spindle-pulling force attenuation.
Analysis and simulation of a new multi-component two-phase flow model with phase transitions and chemical reactions
Authors: Hantke Maren , Müller Siegfried
Published: January 2018

A class-II-model for multi-component mixtures recently introduced in D. Bothe and W. Dreyer, Continuum thermodynamics of chemically reacting fluid mixtures, Acta Mech., 226 (2015), 1757–1805, is investigated for simple mixtures. Bothe and Dreyer were aiming at deriving physically admissible closure conditions. Here the focus is on mathematical properties of this model. In particular, hyperbolicity of the inviscid flux Jacobian is verified for non-resonance states. Although the eigenvalues cannot be determined explicitly but have to be computed numerically an eigenvector basis is constructed depending on the eigenvalues. This basis is helpful to apply standard numerical solvers for the discretization of the model. This is verified by numerical computations for two- and three-component mixtures with and without phase transition and chemical reactions.
Sequanix: a dynamic graphical interface for Snakemake workflows
Authors: Desvillechabrol Dimitri , Legendre Rachel , Rioualen Claire , Bouchier Christiane , van Helden Jacques , Kennedy Sean , Cokelaer Thomas
Published: January 2018

We designed a PyQt graphical user interface—Sequanix—aimed at democratizing the use of Snakemake pipelines in the NGS space and beyond. By default, Sequanix includes Sequana NGS pipelines (Snakemake format) (http://sequana.readthedocs.io), and is also capable of loading any external Snakemake pipeline. New users can easily, visually, edit configuration files of expert-validated pipelines and can interactively execute these production-ready workflows. Sequanix will be useful to both Snakemake developers in exposing their pipelines and to a wide audience of users.

Availability and implementation

Source on http://github.com/sequana/sequana, bio-containers on http://bioconda.github.io and Singularity hub (http://singularity-hub.org).

Supplementary information

Supplementary data are available at Bioinformatics online.
Corrections of fish school area and mean volume backscattering strength by simulation of an omnidirectional multi-beam sonar
Authors: Trygonis Vasilis , Kapelonis Zacharias
Published: January 2018

Fish school descriptors extracted from omnidirectional multi-beam data are biased due to beam width-related effects, and echotraces are distorted in a range-dependent manner that is a function of transducer intrinsic properties, as well as fish school characteristics. This work investigates a simulation approach that models the three-dimensional insonification of fish schools by an omnidirectional fishery sonar in order to assess the bias in measuring two key morphometric and energetic descriptors, namely the horizontal cross-sectional area of schools and their mean volume backscattering strength. Simulated fish schools of different sizes and backscattering properties were insonified at various ranges from the multi-beam transducer, outputting volume backscattering strength echograms. The simulated data were used to develop empirical models that correct the examined descriptors using only information extracted from the observed echotraces. Depending on the difference between the observed mean volume backscattering strength of a school and the echogram processing threshold, mean absolute percentage errors in measured area and volume backscatter reduced from 100.7% and 79.5% to 5.2% and 6.4%, respectively. The mean volume backscattering strength of a school is a key parameter for obtaining fish density estimates, and the results highlight the need for descriptor corrections to better interpret the multi-beam data.
Diary Methods
Authors: Hyers Lauri
Published: January 2018

This book provides an overview of diary research history, design, data collection, data analysis, report writing, evaluation, and ethics. In use for about 100 years now in the social sciences, diary research methods are distinct in the qualitative canon for their mode of data collection. Diary research methods are as flexible as other qualitative methods and can be adapted to suit a variety of epistemological assumptions and research questions, types of diarists and data formats, and styles of analysis. Although diary research can seem daunting, many qualitative researchers have had great success in working with diaries as their primary data source. In this volume, the diary will first be explored historically, from its emergence as a popular cultural phenomenon to its eventual use by social science researchers. Attention will then turn to the use of archival and solicited diaries in qualitative research designs. Next, the basics of designing, analyzing, and writing qualitative diary studies will be reviewed. The volume concludes with a discussion of the strengths, weaknesses, and ethical considerations of qualitative diary research.
Citizenship Education for a Segregated Nation
Authors: McRae Elizabeth Gillespie
Published: January 2018

In the 1920s from Athens, Georgia, Mildred Lewis Rutherford called on white southerners to ensure that the public school maintained racial segregation and the curriculum provided a white supremacist citizenship education. She encouraged white women, the United Daughters of the Confederacy, and the United Confederate Veterans to monitor public education and to make public schools a site for the reproduction of white supremacy. If Jim Crow represented the wisdom of the age, then educators were the political nurturers of the system, and children were the repositories of their efforts. White women did their job. They censored textbooks, promoted Confederate-friendly interpretations of the Civil War, conducted essay contests, offered programs to public schoolteachers, and lobbied state textbook selection committees. They also joined Margaret Robinson and other anti-radical women across the nation to promote Americanization. White segregationist women guaranteed that white children learned the lessons of Jim Crow citizenship.
Campaigning for a Jim Crow South
Authors: McRae Elizabeth Gillespie
Published: January 2018

In the interwar period, Florence Sillers Ogden, Mary Dawson Cain, and Cornelia Dabney Tucker, segregationists in the Deep South, capitalized on their enfranchisement to mobilize voters to shape the system of Jim Crow at the polls. They encouraged women to uphold segregation through political parties, but their politics were as varied as the Jim Crow order they sought to serve. Ogden supported President Franklin Roosevelt and the New Deal for helping out Mississippians and for following the dictates of racial segregation. Cain opposed the Roosevelt’s expansion of social services and worked against the national party as a Jeffersonian Democrat. After Roosevelt’s proposal to re-organize the Supreme Court, Tucker organized a national anti–court-packing campaign, became a Republican, and lobbied for a secret ballot in South Carolina. These women criticized state-level officials for sacrificing conservative political principles for political gain and nourished the seeds of partisan dissent in the Solid South.
The Principle of Legality at the Crossroads of Human Rights and International Criminal Law
Authors: Darcy Shane
Published: January 2018

This chapter explores the treatment of the principle of legality in international criminal law, in particular the rule against ex post facto application of criminal laws, as enshrined in human rights law. It demonstrates that a broadly liberal interpretation of nullum crimen has facilitated judicial creativity and the development of international criminal law by international courts and tribunals. The chapter begins with a general discussion of the principle of legality under international law, before turning to a consideration of the treatment of the principle at Nuremberg and the ad hoc international criminal tribunals for Rwanda and the former Yugoslavia. The final section of the chapter turns to the European Court of Human Rights and examines how it has addressed the rule of non-retroactivity in the context of national prosecutions of international crimes, in particular in Kononov v. Latvia.
Underground Warfare
Authors: Richemond-Barak Daphné
Published: January 2018

This chapter builds on the past to learn about the future: How does today’s use of tunnels differ from yesterday’s? What will tomorrow’s underground warfare look like? These questions are answered through the historical narrative and a database of over 40 years of New York Times reports on the use of tunnels in conflict. The NYT data fills some of the holes left by the absence of literature and helps shape the first typology of tunnels. This chapter offers conceptual and analytical tools for understanding and contending with tunnel warfare. It also encapsulates one of the book’s major arguments that, absent a major technological breakthrough, underground warfare is likely to intensify and continue its rapid diffusion in the coming years, following a pattern resembling that of suicide terrorism.
Misconceptions about Giftedness and the Diagnosis of ADHD and Other Mental Health Disorders
Authors: Lovecky Deirdre V.
Published: January 2018

In the field of gifted education, it commonly thought that behaviors such as inattention, hyperactivity, and impulsivity are common in gifted children, and, therefore, due to these behaviors, they are often being misdiagnosed as having attention deficit hyperactivity disorder (ADHD). The overexcitabilities (OEs), particularly psychomotor OE, are one source of the issue. Gifted children, due to psychomotor OE, are seen as having a high level of ADHD-like behaviors that are mistaken for ADHD. This chapter explores the literature to determine the validity of these ideas. This chapter also describes the risk for gifted children of developing any mental disorder. Finally, best practices to be used in conducting comprehensive evaluations of gifted children to determine both strengths and weaknesses for academic, social, and emotional planning are delineated.
Alcohol Use and Consequences Across Developmental Transitions During College and Beyond
Authors: Ashenhurst James R. , Fromme Kim
Published: January 2018

Alcohol use generally peaks during emerging adulthood, which resides between adolescence and adulthood. For many, this period is also marked by participation in higher education, and college campuses are well-known environments of high-risk drinking. This chapter highlights trajectory groups of heavy episodic drinking and reviews well-studied risk factors for and consequences of alcohol use. Risk factors highlighted include demographics, peer norms, parental awareness and caring, academic motives, personality, and subjective response to alcohol. Those at greatest risk are men, those with greater family wealth, sexual minorities, and Caucasian students. Greater sensation seeking or impulsive personality, low parental awareness, greater stimulation response, and higher peer drinking norms are significant correlates of risky drinking. The consequences of alcohol use examined are aggression, drinking and driving, and alcohol-induced blackouts. The chapter describes findings about special events during which extreme drinking is relatively common: 21st birthdays and football games or other sporting events.
Personality Processes Related to the Development and Resolution of Alcohol Use Disorders
Authors: Sher Kenneth J. , Littlefield Andrew , Lee Matthew
Published: January 2018

This chapter discusses relations between personality and alcohol use disorder (AUD). After reviewing basic terms and concepts in personality research, two major areas of contemporary research are discussed. The first area concerns how personality traits are implicated in etiologic pathways to AUD. This highlights the centrality of personality to conceptualizing AUD and related psychopathology. The second area is research emphasizing movement beyond a static view of personality, recognizing that personality traits are dynamic and change as a function of human development and life transitions. In particular, whereas past research on “maturing out” of AUD emphasized salutary effects of young adult role transitions, recent evidence reveals normative patterns of developmental personality maturation and supports these as additional influences on maturing out. The chapter discusses ways that contextual role effects and personality maturation can perhaps be integrated into a broader model of maturing out of AUD. Implications for future investigation are presented.
Montaigne and the Tolerance of Politics
Authors: Thompson Douglas I.
Published: January 2018

Montaigne and the Tolerance of Politics provides a new interpretation of Michel de Montaigne’s Essais in the context of his activity as a political negotiator between combatant parties during the French Wars of Religion. At the heart of the Essais lies a political conception of tolerance that is rarely considered today. Tolerance is usually conceived as an individual ethical disposition or a moral principle of public law. For Montaigne, tolerance is instead a political capacity: the power and ability to negotiate relationships of basic trust and civil peace with one’s opponents in political conflict. Contemporary thinkers often argue that what matters most for tolerance is how one talks to one’s political opponents: with respect, reasonableness, and civility. For Montaigne, what matters most is not how, but rather that opponents talk to each other across lines of disagreement. Using his own experience negotiating between Catholic and Huguenot parties as a model, Montaigne investigates and prescribes a set of skills and capacities that might help his readers become the kinds of people who can initiate and sustain dialogue with the “other side” to achieve public goods—even when respect, reasonableness, and civility are not yet assured. Montaigne and the Tolerance of Politics argues that this dimension of tolerance is worth recovering and reconsidering in contemporary democratic societies, in which partisan “sorting” and multidimensional polarization have evidently rendered political leaders and ordinary citizens less and less able to talk to each other to resolve political conflicts and to work for shared public goods.