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The dynamic motions of ion-acoustic (IA) waves in plasma are studied by considering the Kappa-Cairns electron distribution. The effect of external periodic force is also considered, here. Using the reductive perturbation technique, a Korteweg-de Vries (K-dV) equation is obtained. The quasiperiodic motions of IA waves are investigated by considering two-dimensional phase portraits and time-series analysis. The effects of non-thermal parameters (i.e., κ, α) and the strength (f0) of the external periodic force on nonlinear travelling wave structures are also discussed. [ABSTRACT FROM AUTHOR]

Local distribution and orientation of anisotropic nanoparticles in microphase-separated symmetric diblock copolymers has been simulated using dissipative particle dynamics and analyzed with a molecular theory. It has been demonstrated that nanoparticles are characterized by a non-trivial orientational ordering in the lamellar phase due to their anisotropic interactions with isotropic monomer units. In the simulations, the maximum concentration and degree of ordering are attained for nonselective nanorods near the domain boundary. In this case, the nanorods have a certain tendency to align parallel to the interface in the boundary region and perpendicular to it inside the domains. Similar orientation ordering of nanoparticles located at the lamellar interface is predicted by the molecular theory which takes into account that the nanoparticles interact with monomer units via both isotropic and anisotropic potentials. Computer simulations enable one to study the effects of the nanorod concentration, length, stiffness, and selectivity of their interactions with the copolymer components on the phase stability and orientational order of nanoparticles. If the volume fraction of the nanorods is lower than 0.1, they have no effect on the copolymer transition from the disordered state into a lamellar microstructure. Increasing nanorod concentration or nanorod length results in clustering of the nanorods and eventually leads to a macrophase separation, whereas the copolymer preserves its lamellar morphology. Segregated nanorods of length close to the width of the diblock copolymer domains are stacked side by side into smectic layers that fill the domain space. Thus, spontaneous organization and orientation of nanorods leads to a spatial modulation of anisotropic composite properties which may be important for various applications. [ABSTRACT FROM AUTHOR]

This work presents an extensive directional paleomagnetic database of the Kiaman reversed superchron. It is composed of 1,459 paleomagnetic directions from igneous rocks corresponding to 91 data sets (or paleomagnetic poles). An almost constant behavior of more concentrated and circular distributions for latitudes higher than 10° was found, which contrasts strongly with predictions of the representative models for the past few million years. We searched for simplified and spatially covariant Giant Gaussian Process (GGP) models that best explain the directional distribution of the Kiaman database. We used the mean strength based on the mean of virtual dipole moment (VDM) results for the period drawn from the available databases. Among the tested models, the one that best explains the directional paleosecular variation of the Kiaman database is the covariant type. According to this model, the correlations between the Gaussian coefficients are valid for the last 10 Myr and the Kiaman superchron. The resulting GGP models have β parameters similar to the 0–10 Ma models, which indicates that the relation between symmetric and antisymmetric families appears unchanged in the geological past. The relative variability of the Kiaman field, as inferred from the ratio αg10¯ from GGP models, is lower than for the past 10 Myr. Thus, as well as the paleointensity, αg10¯ seems to be a proxy that can be used for evaluating the geomagnetic development along the geological time. Key Points: A new database of paleomagnetic directions of igneous Kiaman sitesThe distributions of the Kiaman directions reveal low paleosecular variationThe first Giant Gaussian Process models for ages older than the last 10 million years are presented [ABSTRACT FROM AUTHOR]

The article focuses on theoretical physicist J. Robert Oppenheimer who was introduced to theoretician Paul Dirac and mentions invention of the atom bomb directed by Oppenheimer. Topics discussed include philosophies in the form of dialogue between discussing corpuscularian systems, abuses of rhetoric in learning and natural sciences, and laboratorial facilities not acquired by Royal Society.

Abstract A Ca-containing Mg-4Zn-1MM(mischmetal)-0.1Ca (wt.%, ZEX4101) alloy sheet shows Index Erichsen value of 6.7 mm, which is better than commercial Mg alloy sheets. The good formability is attributed to its weakened basal texture, in which the intensity of the (0001) poles of the recrystallized grains spreads towards the transverse direction. By monitoring the microstructural evolution during the hot rolling and the solution treatment, we found that Ca addition hinders the formation of strong basal texture during the rolling. During the subsequent solution treatment, static recrystallization mainly proceeds by the growth of dynamically recrystallized grains, and then the weak texture feature of the dynamically recrystallized grains is maintained in the ZEX4101 alloy sheet. It is hypothesized that co-segregation of Zn and Ca atoms to the grain boundaries prevents the rotation of the (0001) poles of the dynamically recrystallized grains toward the sheet normal direction, resulting in the development of weak basal texture in the ZEX4101 alloy sheet. Highlights • Trace Ca addition weakens basal texture and increases room-temperature stretch formability in Mg-4Zn-1MM alloy sheet. • Ca-containing Mg-4Zn-1MM-0.1Ca alloy sheet causes co-segregation of Zn and Ca atoms to grain boundaries. • Co-segregation of Zn and Ca prevents formation of strong basal texture during hot-rolling. [ABSTRACT FROM AUTHOR]

Abstract The formation of solid solution alloy systems happens to two kinds of atoms with similar radii to comply with Hume-Rothery rules as a common feature. In recent years, as a useful tool, Machine Learning (ML) has been widely used in material science research to obtain useful information, including material preparation and process and so on. In this work, we use the method of Support Vector Machine (SVM) to predict solid solubility with a small dataset in order to provide evidence for the correctness of the Hume-Rothery rules and find factors of solid solubility. The results indicate that the main factors of solid solubility include three traditional Hume-Rothery factors. The solid solubility can also be evaluated by Support Vector Regression (SVR) with Radial basis function (RBF) kernel. Highlights • It proved the Hume-Rothery rules' three main factors with Support Vector Classification Machine Learning method. • This work can judge the relative importance of each factor in Hume-Rothery rules to the solid solubility. • It can be more accurate to judge whether any metal alloy is soluble if the more factors are extended. • When the six factors are used with Support Vector Regression, it can be known how many the solid solubility is. [ABSTRACT FROM AUTHOR]

Abstract The influence of global interactions between the static atomic structure and the valence electrons on structure formation in binary Al-(Ni,Cu,Zr), Zr-(Ni,Cu) and ternary Al-(Ni,Cu)-Zr metallic glasses is investigated over wide concentration ranges and discussed in terms of a Hume-Rothery-like theory by analysing and comparing data available in the literature. The results suggest that global interactions lead to an improvement of thermal stability and glass-forming ability. A complete understanding of structure formation in the considered alloys is assumed to be possible only by taking into account both local and global effects. • The effect of global interactions on thermal stability and glass-forming ability in Al-(Ni,Cu)-Zr metallic glasses is analysed. • A Hume-Rothery-like effect according to a mean valence of 1.5 electrons per atom plays a major role. • Local and global effects mutually support each other to yield the energetically most favorable structure. • Correlations with other properties are pointed out. [ABSTRACT FROM AUTHOR]

In addition to clarifying morphological structures of the Earth's radiation belts, it has also been a major achievement of the Van Allen Probes mission to understand more thoroughly how highly relativistic and ultrarelativistic electrons are accelerated deep inside the radiation belts. Prior studies have demonstrated that electrons up to energies of 10 megaelectron volts (MeV) can be produced over broad regions of the outer Van Allen zone on timescales of minutes to a few hours. It often is seen that geomagnetic activity driven by strong solar storms (i.e., coronal mass ejections, or CMEs) almost inexorably leads to relativistic electron production through the intermediary step of intense magnetospheric substorms. In this study, we report observations over the 6‐year period 1 September 2012 to 1 September 2018. We focus on data about the relativistic and ultrarelativistic electrons (E≥5 MeV) measured by the Relativistic Electron‐Proton Telescope sensors on board the Van Allen Probes spacecraft. This work portrays the radiation belt acceleration, transport, and loss characteristics over a wide range of geomagnetic events. We emphasize features seen repeatedly in the data (three‐belt structures, "impenetrable" barrier properties, and radial diffusion signatures) in the context of acceleration and loss mechanisms. We especially highlight solar wind forcing of the ultrarelativistic electron populations and extended periods when such electrons were absent. The analysis includes new display tools showing spatial features of the mission‐long time variability of the outer Van Allen belt emphasizing the remarkable dynamics of the system. Key Points: Essential factors are plentiful substorm "seed particles" and high‐speed (V > 500 km/s) solar wind forcingThe entire relativistic electron population can be wiped out in a few hours by shock wave impact but can rapidly be replenishedVery long intervals have been observed without multimegaelectron volt electrons in the outer belt due to low solar wind driving [ABSTRACT FROM AUTHOR]

Abstract The interaction between screw dislocations and oxygen interstitial atoms is studied with ab initio calculations in hexagonal close-packed titanium. Our calculations evidence a strong repulsion when the solute atoms are located in the dislocation glide plane, leading to spontaneous cross-slip, which allows the dislocation to bypass the atomic obstacle. This avoidance process explains several experimental observations in titanium in presence of oxygen: (1) a larger lattice friction against screw dislocation motion, (2) a reduction of the dislocation glide distance in prismatic planes and (3) an enhancement of cross-slip in pyramidal planes. Graphical Abstract [ABSTRACT FROM AUTHOR]

Abstract Using first-principles calculations, we have studied the energetics and local atomic structure of Sc, Y, La, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, As, Sb, and Bi in Be. We find Cr substitutes for one, V and Mo for three, La for five, and others for four Be atoms. Dissolution of Zr, Hf, Sc, and Y is exothermic, and they all tend to aggregate. Scandium has the weakest aggregation tendency and thus is expected to enhance more effectively the superplasticity of Be. These large atoms can trap self-interstitials and vacancies, improving the swelling resistance of Be under irradiation. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract The electronic and magnetic properties of Ag, Cu or Mg doped NiO are systematically studied in order to reveal the ferromagnetic half-metallic behavior by means of first-principle calculations. In the band structure and density of states (DOS), we find that impurity states crossing Fermi level are induced in the spin down channel, while band gap only appears in the Ni 31 XO 32 (X = Ag, Cu) systems in the spin up channel. The analysis of electron spin density and magnetic show that the dopant atoms (Ag or Cu) and its neighbor O atoms exhibit strong polarization as well as the resultant magnetic moments. However, Mg doping system do not exhibit similar phenomenon. These results indicate that the nonmagnetic dopants of Ag or Cu can introduce the ferromagnetic half-metallic properties in the Ni 31 AgO 32 or Ni 31 CuO 32 system. Highlights • The structure optimization shows the ferromagnetic sate is more stable than the nonmagnetic state for Ni 31 XO 32 (X = Ag, Cu, Mg). • The half-metallic property is only observed in the Ag-doped and Cu-doped system, but not in the Mg-doped system. • The broken of spin density symmetry is the mainly reason for the creation of half-metallic property due to the strong hybridization between the Ag or Cu atom and O atoms. [ABSTRACT FROM AUTHOR]

Abstract The half-metallic behaviour, magnetic, mechanical and thermal properties of LiMgPdSn-type (Ni/Pd/Ru) ZrTiAl alloys were investigated by using ab initio calculations. The generalized gradient approximation in the form of PBE was utilized to treat the exchange-correlation energy for the entire calculations and GGA + U was utilized for strongly correlated electrons of ZZrTiAl (Z = Ni, Pd, Ru) compounds during electronic structure calculations. We used the values of U as 2eV for (Ni/Pd/Ru), 1eV for Zr and 1.5eV for Ti elements. The investigated lattice parameters and magnetic properties of the PdZrTiAl alloy are in close agreement with theoretical results. The estimated cohesive energy confirms the chemical structural stability of ZZrTiAl compounds. The total magnetic moments of (Ni/Pd/Ru) ZrTiAl alloys are 3.00, 3.01 and 1μ B /f.u., satisfying the SP rule. Within GGA + U, ZZrTiAl alloys show half-metallic nature with wide band gaps of 0.56 eV, 0.57eV and 0.78 eV respectively confirming applications in spintronic devices. The elastic constants reveal that the ZZrTiAl alloys are mechanically steady and the B/G ratio confirmed that the alloys considered are ductile in nature, which is consistent with Poisson's ratio. In addition, the Debye temperature, melting temperature and Grüneisen parameter were investigated by using average sound velocity and elastic symmetry. Highlights • The investigated (Ni/Pd/Ru) ZrTiAl alloys show half-metallic behaviour with wide energy band gaps. • The magnetic properties of (Ni/Pd/Ru) ZrTiAl alloys satisfied the Slater-Pauling rule. • The (Ni/Pd/Ru) ZrTiAl alloys are mechanically stable and ductile nature. • The Debye temperature of considered alloys are predicted by using calculated elastic constants. [ABSTRACT FROM AUTHOR]

Abstract The dynamic vacuum effect induced by the charge exchange beam loss will seriously limit the ion intensity and beam lifetime in the Booster Ring (BRing) of the High-Intensity Heavy Ion Accelerator Facility (HIAF). A dedicated collimation system has been designed to decrease the ion-induced gas desorption to suppress the dynamic vacuum effect. In order to reach 100% collimation efficiency, the optics lattice of BRing has been changed from original FODO to DBA structure. The distance between dipole and quadrupole in each lattice cell of BRing was optimized to maintain the high collimation efficiency. The hardware structure of the collimator was designed based on the simulation result and mechanical instrument control principle in the UHV vacuum system. The vacuum chamber and pump installment with collimators has been designed. A prototype collimator with vacuum chamber has been installed on the beamline to measure the gas desorption with beam and verify the availability and reliability of mechanical design. This prototype collimator has passed factory field tests and used to measure the gas desorption rate with the beam 112Sn 26 + at the energy 150 MeV/u successfully. [ABSTRACT FROM AUTHOR]

Cytochrome c oxidase (CcO) reduces dioxygen to water and harnesses the chemical energy to drive proton translocation across the inner mitochondrial membrane by an unresolved mechanism. By using time-resolved serial femtosecond crystallography, we identified a key oxygen intermediate of bovine CcO. It is assigned to the PR-intermediate, which is characterized by specific redox states of the metal centers and a distinct protein conformation. The heme a3 iron atom is in a ferryl (Fe4+ = O2-) configuration, and heme a and CuB are oxidized while CuA is reduced. A Helix-X segment is poised in an open conformational state; the heme a farnesyl sidechain is H-bonded to S382, and loop-I-II adopts a distinct structure. These data offer insights into the mechanism by which the oxygen chemistry is coupled to unidirectional proton translocation. [ABSTRACT FROM AUTHOR]

Graphical abstract In this article, we report an efficient approach to fabricating CdS nanoparticle decorated WO 3 inverse opal (CdS/WO 3 IO) nano-heterojunction photocatalyst. Three-dimensional ordered structure of CdS/WO 3 IO is beneficial to enhance light adsorption ability. The formation of a Z-scheme CdS-WO 3 photocatalyst leads to accelerated charge carrier transfer and efficient separation of photogenerated electron-hole pairs. This discovery provides new opportunities for the design and preparation of Z-scheme photocatalyst with excellent Rhodamine B degradation. Abstract A novel CdS nanoparticle decorated WO 3 inverse opal nano-heterojunction photocatalyst is successfully prepared for Rhodamine B degradation. Although WO 3 cannot be used for photocatalytic degradation of organic pollutants alone, it can significantly enhance photocatalytic efficiency through a Z-scheme photocatalytic system by coupling with CdS. The optimal pseudo-first-order reaction rate constant of C10 is estimated to be 0.03575 min−1 and 8.9 times as high as that of pure WO 3 IO. The formation of a Z-scheme CdS-WO 3 photocatalyst leads to accelerated charge carrier transfer and efficient separation of photogenerated electron-hole pairs. This discovery provides new opportunities for the design and preparation of Z-scheme photocatalyst with excellent Rhodamine B degradation. [ABSTRACT FROM AUTHOR]

Encouraged by the evidence for Z = 6 magic number in neutron-rich carbon isotopes, we have performed relativistic mean-field plus BCS calculations to investigate ground state properties of entire chains of isotopes (isotones) with Z (N) = 6 including even and odd mass nuclei. Our calculations include deformation, binding energy, separation energy, single particle energy, root mean squared radii, along with charge and neutron density profile, etc., and are found to be an excellent match with latest experimental results demonstrating Z = 6 as a strong magic number. N = 6 is also found to have a similar kind of strong magic character. [ABSTRACT FROM AUTHOR]

Abstract Electroencephalography (EEG) is a non-invasive brain imaging technique that describes neural electrical activation with good temporal resolution. Source localization is required for clinical and functional interpretations of EEG signals, and most commonly is achieved via the dipole model; however, the number of dipoles in the brain should be determined for a reasonably accurate interpretation. In this paper, we propose a dipole source localization (DSL) method that adaptively estimates the dipole number by using a novel information criterion. Since the particle filtering process is nonparametric, it is not clear whether conventional information criteria such as Akaike's information criterion (AIC) and Bayesian information criterion (BIC) can be applied. In the proposed method, multiple particle filters run in parallel, each of which respectively estimates the dipole locations and moments, with the assumption that the dipole number is known and fixed; at every time step, the most predictive particle filter is selected by using an information criterion tailored for particle filters. We tested the proposed information criterion first through experiments on artificial datasets; these experiments supported the hypothesis that the proposed information criterion would outperform both AIC and BIC. We then analyzed real human EEG datasets collected during an auditory short-term memory task using the proposed method. We found that the alpha-band dipoles were localized to the right and left auditory areas during the auditory short-term memory task, which is consistent with previous physiological findings. These analyses suggest the proposed information criterion can work well in both model and real-world situations. [ABSTRACT FROM AUTHOR]

The article focuses on the controversy between Former Yugoslav Republic of Macedonia (FYROM) and Greece over the former's constitutional name, for the cities of Athens and Skopje. Topics discussed include historical background of the dispute, evaluation of Greek government its resolution, and FYROM's prospects for entering the European Union and the North Atlantic Treaty Organization.

Abstract Several experiments of neutron generation using high intensity laser sources, with a power exceeding 1019W/cm 2 via TNSA (Target Normal Sheath Acceleration) or other similar methods, have been performed in the past years in different laboratories. However, so far there is no one running neutron source based on such a technology. In the framework of the Conceptual Report Design of a new accelerator in the Eupraxia project (Walker et al., 2017, [ 1 ]) we are studying the possibility to have a laser-based neutron source, not only by TNSA but also from self-injection schemes. We focus our attention on the applications in cultural heritage studies as well also on the complementary role that such a source can have in the framework of large facilities devoted to radiation production. [ABSTRACT FROM AUTHOR]

Abstract The statistical model with exact conservation of baryon number, electric charge, and strangeness – the Canonical Statistical Model (CSM) – is used to analyze the dependence of yields of light nuclei at midrapidity on charged pion multiplicity at the LHC. The CSM calculations are performed assuming baryon-symmetric matter, using the recently developed Thermal-FIST package. The light nuclei-to-proton yield ratios show a monotonic increase with charged pion multiplicity, with a saturation at the corresponding grand-canonical values in the high-multiplicity limit, in good qualitative agreement with the experimental data measured by the ALICE collaboration in pp and Pb–Pb collisions at different centralities and energies. Comparison with experimental data at low multiplicities shows that exact conservation of charges across more than one unit of rapidity and/or a chemical freeze-out temperature which decreases with the charged pion multiplicity improves agreement with the data. [ABSTRACT FROM AUTHOR]

The Horizon Quantum Mechanics is an approach that allows one to analyse the gravitational radius of spherically symmetric systems and compute the probability that a given quantum state is a black hole. We first review the (global) formalism and show how it reproduces a gravitationally inspired GUP relation. This results leads to unacceptably large fluctuations in the horizon size of astrophysical black holes if one insists in describing them as (smeared) central singularities. On the other hand, if they are extended systems, like in the corpuscular models, no such issue arises and one can in fact extend the formalism to include asymptotic mass and angular momentum with the harmonic model of rotating corpuscular black holes. The Horizon Quantum Mechanics then shows that, in simple configurations, the appearance of the inner horizon is suppressed and extremal (macroscopic) geometries seem disfavoured. [ABSTRACT FROM AUTHOR]

Background: Vitamin B12 deficiency, which may cause serious neuropsychiatric damage, is common in the elderly. The non-specific clinical features of B12 deficiency and unreliable serum parameters make diagnosis difficult. We aimed to evaluate the value of oral “beefy red” patches as a clinical marker of B12 deficiency. Methods: A diagnostic study was conducted in patients complaining of oral soreness, burning sensation, or severe recurrent oral ulcers. Patients underwent clinical examination and laboratory investigations, including complete blood count and estimation of serum B12, folate, iron, and ferritin levels. Resolution of clinical signs and symptoms after 1 month of B12 supplement was regarded as the diagnostic gold standard. Results: Of 136 patients, 70 had B12 deficiency. Among these patients, the oral “beefy red” patch was observed in 61, abnormal mean corpuscular volume (MCV) was noted in 30, and serum cobalamin levels [ABSTRACT FROM AUTHOR]

Abstract: Gas‐phase activation of CO2 by chloride tagged metal atoms, [ClM]− (M=Mg, Zn), has been investigated by mass spectrometry and high‐level quantum chemistry. Both metals activate CO2 with significant bending of the CO2 moiety to form complexes with the general formula [ClM,CO2]−. The structure of the metal–CO2 complex depends on the method of formation, and the energy landscapes and reaction dynamics have been probed by collisional induced dissociation and thermal ion molecule reactions with isotopically labeled species. Having established these structural relationships, the gas‐phase reactivity of [ClM(κ2‐O2C)]− with acetaldehyde (here considered a carbohydrate mimic) was then studied. Formation of lactate and enolate‐pyruvate complexes are observed, showing that CO2 fixation by C−C bond formation takes place. For M=Zn, even formation of free pyruvate ([C3H3O3]−) is observed. Implications of the observed CO2 reactivity for the electrochemical conversion of carbon dioxide, and to biochemical and artificial photosynthesis is briefly discussed. Detailed potential energy diagrams obtained by the quantum chemical calculations offer models consistent with experimental observation. [ABSTRACT FROM AUTHOR]

Through first-principles calculations, we investigate the electronic structures, formation energy and transition level of the selected group V and VII impurities in the two-dimensional ZrSe 2 monolayer. Our results indicate that group V and VII atoms substituting Se atom can be easier under Zr-rich experiment conditions. Moreover, group V element substituting doping can induce p- type carrier due to their negative formation energy and shallow transition level, while group VII doping can not be effective to induce the n- type impurities. In particular, N substituting Se exhibits the lowest formation energy and shallowest transition level, which indicates that N impurities can offer effective p -type carriers in the ZrSe 2 monolayer. [ABSTRACT FROM AUTHOR]

Mass spectrometry was used to identify the decomposition products of two typical photoresist polymers, Novolak and polymethylmethacrylate, by H atoms produced on hot wire surfaces. The production of CH 4 and CO was confirmed for both polymers. Other possible products are C 3 H 8 , C 4 H 10 or C 4 H 8 , and some esters such as CH 3 COOC 2 H 5 . The production of CO 2 , C 2 H 4 , C 2 H 6 , alcohols, and aromatics are minor. The possible decomposition mechanisms are discussed on the basis of density functional calculations of the energetics. [ABSTRACT FROM AUTHOR]

Metal wires, such as W, Mo, and Ta, can be boronized to become sinks of B atoms by heating them in the presence of a mixture of H 2 and H 3 NBH 3 or (BH) 3 (NH) 3 . These boronized wires behave as sources of B atoms when heated in vacuum. The density of B atoms released to the gas phase increases with the addition of H 2 and can be > 10 11 cm − 3 , which is enough for surface doping. The release is stable and continues for more than several hours when boronized for 1 h. Since the metal wires are not nitrided, contamination by N atoms is not expected. H 3 NBH 3 and (BH) 3 (NH) 3 are not explosive, and wires boronized by these species can be used as safe and contamination-free sources of B atoms for surface doping. [ABSTRACT FROM AUTHOR]

In this paper, we assess the ability of descriptors defined within the framework of the quantum theory of atoms-in-molecules to retrieve trans and cis structural effects in 42 d octahedral carbonyl organometallic complexes involving cobalt and rhodium atoms. More specifically, correlations between bond lengths in trans or cis position with respect to common orienting ligands and both local (such as molecular electrostatic potential values or the properties of critical points of the electron density Laplacian field) and integrated (over the metal atomic basin, such as multipolar moments, various energy contributions, condensed conceptual DFT quantities) properties are investigated, casting some light on the physicochemical features that drive this fundamental structural effect. [ABSTRACT FROM AUTHOR]

Experimentally, Ca-doped β-GaO was found to increase photocatalytic activity by about three times compared with undoped photocatalyst. However, the same host doped with La had minor influence on photocatalytic performance. Doping with Ti leaded to very low H and O evolution rate. In this work, effects of different metal dopants on photocatalytic performance of β-GaO-based photocatalyst have been explored using first-principles density functional theory calculations. Our calculated results suggest that energy states introduced by dopant Ca in the bandgap of β-GaO are close to the valence band maximum. New states allow for efficient electron replenishment and thus reduce the probability of trapping electrons from the conduction band. In contrast, impurity states introduced by dopant Ti are significantly higher than the valence band maximum, which may become an isolated recombination center and thus badly decrease the rate of water-splitting reaction. Adding La had no effect on the electronic structure of β-GaO, which has seldom influence on photocatalytic activity. [ABSTRACT FROM AUTHOR]

The electron-impact ionization of inert gases for asymmetric final state energy sharing conditions has been studied in detail. However, there have been relatively few studies examining equal energy final state electrons. We report in this communication the results of triple differential cross sections (TDCSs) for electron impact ionization of Ar (3 p) for equal energy sharing of the outgoing electrons. We calculate TDCS in the modified distorted wave Born approximation (DWBA) formalism including post collision interaction (PCI) and polarization potential. We compare the results of our calculation with available measurements [Phys. Rev. A 87, 022712 (2013)]. We study the effect of PCI, target polarization on the trends of TDCS for the single ionization of Ar (3 p) targets. Graphical abstract: [ABSTRACT FROM AUTHOR]

In a series of previous papers we proved an accurate connection between quantum and classical equations in the case of electrodynamic systems. We have used this connection to elaborate simplified models for systems composed of very intense laser beams and electrons or atoms. These models are in good agreement with numerous experimental data from literature. In this paper we develop the above approach for the new field of interactions between ultraintense laser beams, having intensities in the range 10 − 10 W/cm, and electron plasmas. We show that in this case new effects take place, such as the fact that the variation of the phase of the field at the point where the electron is situated, decreases when the intensity of the field increases, due to a strong relativistic behavior. This effect leads to an aperiodic behavior of the radiations generated by above interactions, and to a possible new method for solitary waves generation. Graphical abstract: [ABSTRACT FROM AUTHOR]

The role of nitrogen doping on the stability and memory window of resistive state switching in N-doped Ta2O5 deposited by atomic layer deposition is elucidated. Nitrogen incorporation increases the stability of resistive memory states which is attributed to neutralization of electronic defect levels associated with oxygen vacancies. The density functional simulations with the screened exchange hybrid functional approximation show that the incorporation of nitrogen dopant atoms in the oxide network removes the O vacancy midgap defect states, thus nullifying excess defects and eliminating alternative conductive paths. By effectively reducing the density of vacancy-induced defect states through N doping, 3-bit multilevel cell switching is demonstrated, consisting of eight distinctive resistive memory states achieved by either controlling the set current compliance or the maximum voltage during reset. Nitrogen doping has a threefold effect: widening the switching memory window to accommodate the more intermediate states, improving the stability of states, and providing a gradual reset for multi-level cell switching during reset. The N-doped Ta2O5 devices have relatively small set and reset voltages (<1V) with reduced variability due to doping. [ABSTRACT FROM AUTHOR]

The hematological parameters and metallothionein (MT) levels in the liver, kidney and muscles were measured in bullfrog tadpoles, Lithobates catesbeianus , following exposures to 1 μg L −1 of zinc (Zn), copper (Cu) and cadmium (Cd) alone or in combination (1:1 and 1:1:1) for 2 and 16 days. Metal accumulation occurred in all organs, with the highest values found in the kidney, followed by the muscles and liver. After exposure to isolated metals, the accumulation was in the following order: Cd > Zn > Cu in the liver and muscles and Cd > Cu > Zn in the kidney. Exposure to combined metals (Zn + Cu, Zn + Cd, Cu + Cd and Zn + Cu + Cd) revealed complex responses, such as metal accumulation increased or decreased over the exposure periods, suggesting possible competion at the uptake sites and/or metabolization and elimination processes in each organ. The MT concentration increased in the organs of tadpoles following metal exposure alone, mainly in the liver, for both periods. After the combined exposures, the MT levels were higher in the liver and muscles at 16 days, suggesting that the interaction between metals was additive, and the level was decreased in the kidney after 2 and 16 days of exposure. The whole blood hemoglobin content (Hb), red blood cell count (RBCs) and mean corpuscular hemoglobin (MCH) differed from the control groups after 2 and 16 days of exposure, showing changes in the improvement of oxygen transport. The number of lymphocytes increased, and the levels of neutrophils, eosinophils, basophils and monocytes were reduced after exposure to the metals. The changes in blood cells suggested that tadpoles have a mechanism to improve oxygen transport probably because of the increased oxygen demand and a general reduction in defense cells. The exposure of L. catesbeianus to metals during the larval phase can generate long-term dysfunction to a degree, which could lead to alterations in their health status. [ABSTRACT FROM AUTHOR]

In this work we present unique signatures manifested by the local electronic properties of the topological surface state in Bi2Te3 nanostructures as the spatial limit is approached. We concentrate on the pure nanoscale limit (nanoplatelets) with spatial electronic resolution down to 1 nm. The highlights include strong dependencies on nanoplatelet size: (1) observation of a phase separation of Dirac electrons whose length scale decreases as the spatial limit is approached, and (2) the evolution from heavily n-type to lightly n-type surface doping as nanoplatelet thickness increases. Our results show a new approach to tune the Dirac point together with reduction of electronic disorder in topological insulator (TI) nanostructured systems. We expect our work will provide a new route for application of these nanostructured Dirac systems in electronic devices. [ABSTRACT FROM AUTHOR]

A 60-day experiment was carried out to delineate the role of dietary pyridoxine (DP) in Labeo rohita fingerlings in modulating immunity and prevention of fungal infection. Two hundred and seventy fingerlings were randomly distributed into three treatments in triplicates. Three iso-caloric and iso-nitrogenous purified diets were prepared with graded levels of pyridoxine. Three experimental groups were C (0.0% DP), T1 (0.01% DP) and T2 (0.02% DP). The role of dietary pyridoxine in modulating immunity and prevention of fungal infection was assessed by haemato-immunological parameters like erythrocyte counts (EC), leucocyte counts (LC), haemoglobulin (Hb), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), nitro-blue tetrazolium (NBT), phagocytic activity, albumin, globulin, total plasma protein, albumin/globulin and by challenge study with Saprolegnia parasitica , where relative percentage survival (RPS) were recorded. Hb, PCV, MCV, MCH, NBT, total plasma protein, albumin, globulin contents, lysozyme and phagocytic activity was significantly (P < 0.05) higher in DP fed group. Significantly (P < 0.05) higher RPS was recorded from T2 group fed with 0.02% DP for 45 days. Hence, DP has the capacity to stimulate nonspecific immunity and increase resistance to S. parasitica infection in L. rohita fingerlings. [ABSTRACT FROM AUTHOR]

A capacitive detection of liquid ethanol using reactive, thermally oxidized films constructed from electrochemically synthesized porous silicon (PSi) is demonstrated. The sensor elements are fabricated as meso-PSi (pore sizes <50 nm, pore thickness ∼7 μm), with Ag metallic contacts made exclusively at the backside of bulk silicon, and ethanol sensing is achieved by measurement of the real-time capacitance and conductance. The thermally oxidized sensor displays excellent infiltration-evaporation behavior with a tremendous reversible capacitance change towards ethanol. The capacitance increased by forty-fold more than its margin which is the greatest capacitance response ever recorded compared to previously investigated devices. The control device of non-porous Si showed no response, while the sensor response using the original hydrophobic PSi surface exhibited almost a half sensitivity of the thermal oxide sensor. The response to water is achieved only at the oxidized surface and found to be ∼one quarter of the ethanol sensitivity, dependent on parameters such as vapor pressure and surface tension. The capacitance response retains ∼92% of its initial value after continuous nine cyclic runs and the sensors presumably keep long-term stability after three weeks storage, demonstrating excellent durability and storage stability. The observed behavior in current system is likely explained by the interface interaction due to dipole moment effect. The results suggest that the current sensor structure and design can be easily made to produce notably higher sensitivities for reversible detection of various analytes. [ABSTRACT FROM AUTHOR]

An isotropic component of high energy γ -ray spectrum measured by Fermi LAT constrains the proton component of UHECR. The strongest restriction comes from the highest, ( 580 − 820 ) GeV, energy bin. One more constraint on the proton component is provided by the IceCube upper bound on ultrahigh energy cosmogenic neutrino flux. We study the influence of these restrictions on the source properties, such as evolution and distribution of sources, their energy spectrum and admixture of nuclei. We also study the sensitivity of restrictions to various Fermi LAT galactic foreground models (model B being less restrictive), to the choice of extragalactic background light model and to overall normalization of the energy spectrum. We claim that the γ -ray-cascade constraints are stronger than the neutrino ones, and that however many proton models are viable. The basic parameters of such models are relatively large γ g and not very large z max  . The allowance for H e 4 admixture also relaxes the restrictions. However we foresee that future CTA measurements of γ -ray spectrum at E γ ≃ ( 600 − 800 ) GeV, as well as resolving of more individual γ -ray sources, may rule out the proton-dominated cosmic ray models. [ABSTRACT FROM AUTHOR]

We propose an explanation for the origin of n-type electrical conductivity in SnO2 based on the results obtained from the DFT+U simulations. Two competitive intrinsic point defects, namely oxygen vacancy and hydrogen impurity, have been considered at different positions within the crystalline lattice in order to find out the equilibrium configurations and to analyze corresponding density of states (DOS) patterns along with the electron localization function (ELF). It has been demonstrated that hydrogen could be solely responsible for the n-type conductivity whereas the oxygen vacancy appears to have not a notable influence upon it. The computational analysis is backed up by some experimental data for undoped tin dioxide. [ABSTRACT FROM AUTHOR]

Deep proton writing (DPW) is a fabrication technology developed for the rapid prototyping of polymer microstructures. We use polymethylmethacrylate (PMMA) substrates, which act as a positive resist, for irradiation with a collimated 12-MeV energy proton beam. Using 12 MeV enables the irradiation of increasingly thick PMMA substrates with less conicity of the sidewalls compared to the lower energies used in previous work. A microhole of 47.7 µm diameter over a depth of 1 mm is achieved, leading to a maximum aspect ratio of 21:1. The sidewalls of the irradiated structures show a slightly conical shape and their root-mean-square surface roughness is lower than 50 nm averaged over 72 measured areas of 56 µm × 44 µm. This means that DPW components have optical surface quality sidewalls for wavelengths larger than 400 nm. Based on the trade-off among the sidewall roughness, conicity, and the development time, we determine that the optimal proton fluence for 12-MeV DPW in PMMA is 7.75 × 106 µm-2. Finally, we discuss some high aspect ratio microstructures with optical surface quality that were created with DPW to be used for a myriad of applications, such as micromirrors, microlenses, optofluidic devices, and high-precision alignment structures for single-mode optical fiber connectors. [ABSTRACT FROM AUTHOR]

This paper proposes a multi-level video representation by stacking the activations of motion features, atoms, and phrases (MoFAP). Motion features refer to those low-level local descriptors, while motion atoms and phrases can be viewed as mid-level 'temporal parts'. Motion atom is defined as an atomic part of action, and captures the motion information of video in a short temporal scale. Motion phrase is a temporal composite of multiple motion atoms defined with an AND/OR structure. It further enhances the discriminative capacity of motion atoms by incorporating temporal structure in a longer temporal scale. Specifically, we first design a discriminative clustering method to automatically discover a set of representative motion atoms. Then, we mine effective motion phrases with high discriminative and representative capacity in a bottom-up manner. Based on these basic units of motion features, atoms, and phrases, we construct a MoFAP network by stacking them layer by layer. This MoFAP network enables us to extract the effective representation of video data from different levels and scales. The separate representations from motion features, motion atoms, and motion phrases are concatenated as a whole one, called Activation of MoFAP. The effectiveness of this representation is demonstrated on four challenging datasets: Olympic Sports, UCF50, HMDB51, and UCF101. Experimental results show that our representation achieves the state-of-the-art performance on these datasets. [ABSTRACT FROM AUTHOR]

Dielectrophoresis for bio-particle manipulation has been drawing much attention in recent years. The equivalent dipole moment has been widely used to calculate dielectrophoretic forces on a particle, but this method falls short to describe the interaction between neighboring particles. The Maxwell stress tensor method (MST) is theoretically rigorous for particle interaction, but it will cost huge computing resource. In this paper, an iterative dipole moment method (IDM) is presented to investigate the interaction between multiple dielectrophoretic particles in a two-dimensional electric field. Without any cumbersome numerical computation, the inter-particle forces and the particle trajectories calculated by the IDM method are found to be in good agreement with those by the MST method for some published results. Furthermore, it is found that the final stable particle chain patterns strongly depend on the initial configuration of the particle distribution. An arbitrary small disturbance to the particle locations may lead to dramatically different motion trajectories and final particle chains. [ABSTRACT FROM AUTHOR]

A modified expression for the Andreev reflection coefficient is derived taking into account strong electronphonon interactions. A dependence of the superconducting order parameter ∆ is numerically modeled for magnesium diboride. The current-voltage characteristics and the dI/dV spectra of the dynamic conductivity of superconductor-normal metal-superconductor (SNS) contacts based on strongly coupled superconductors are calculated for the Averin-Bardas model using the modified Andreev reflection coefficient (on an example of magnesium diboride). Calculations are performed for the mode of high transparency (0.9-0.98). The special features of the SNS contacts based on strongly coupled superconductors are shown. [ABSTRACT FROM AUTHOR]

Results of experimental investigations of amplitude-temporal and spectral characteristics of radiation of a pulse-periodic discharge plasma initiated in nitrogen by runaway electrons are presented. The discharge was initiated by high-voltage nanosecond voltage pulses with repetition frequency of 60 Hz in a sharply inhomogeneous electric field in a gap between the conic potential cathode and the planar grounded aluminum anode. It is established that intensive lines of Al I atoms and Al II atomic ions, lines of N I atoms and N II ions, bands of the first (1) and second positive (2) nitrogen systems, as well as bands of cyanogen CN are observed in the emission spectrum of the discharge plasma under the given excitation conditions. [ABSTRACT FROM AUTHOR]

The article focuses on the ability of physicists to visualize condensed-matter systems' accommodation of dipole moment competing interactions through magnetic structure fabrication into nanoscale arrays. Topics discussed include the fabrication of magnetic structure, the thermalization of energy, and the development of geometries in revealing the emergent behavior from thermalized system.

The term “superalkali” (SA) refers to the species with the ionization energy lower than alkali metals (M). Such species possess an excess electron, which is responsible for their high reducing capacity, enhanced electro-optical properties and tendency to form a variety of charge transfer salts. Utilizing second order Møller–Plesset (MP2) perturbation theory we examine the interaction of SA species (SA = FLi2, OLi3, and NLi4) with M atoms (M = Li, Na, and K), which results in the formation of stable hyperalkalized SA–M species. We have analyzed their structures, bonding and stability. The effect of the size of SA species and the atomic number of M on the electronic properties of SA–M species has also been explored. The ionization energies (IEs) and HOMO–LUMO gaps of SA–M decrease with the decrease in the IE of M (Li ＞ Na ＞K) and/or increase in the size of SA (FLi2 ＜ OLi3 ＜ NLi4). In contrast, their mean polarizability (αo) and first order static hyperpolarizability (βo) increase. For instance, the βo values of OLi3–M range from 0 (M = Li) to 2.8 × 104 a.u. (M = K), which reach 3.6 × 104 a.u. for NLi4–Na. These values are large enough to establish the significant nonlinear optical (NLO) properties of SA–M species. Our CIS calculations show that these larger βo values result due to lower excitation energies, larger transition dipole moments and oscillator strengths for the crucial excited states of SA–M species. These findings may guide the design of potential NLO materials and a new series of alkalides, the species with negatively charged alkali atoms. [ABSTRACT FROM AUTHOR]

A new hybrid kinetic electron model is developed for electrostatic full- f gyrokinetic simulations of the ion temperature gradient driven trapped electron mode (ITG-TEM) turbulence at the ion scale. In the model, a full kinetic electron model is applied to the full- f gyrokinetic equation, the multi-species linear Fokker–Planck collision operator, and an axisymmetric part of the gyrokinetic Poisson equation, while in a non-axisymmetric part of the gyrokinetic Poisson equation, turbulent fluctuations are determined only by kinetic trapped electrons responses. By using this approach, the so-called ω H mode is avoided with keeping important physics such as the ITG-TEM, the neoclassical transport, the ambipolar condition, and particle trapping and detrapping processes. The model enables full- f gyrokinetic simulations of ITG-TEM turbulence with a reasonable computational cost. Comparisons between flux driven ITG turbulence simulations with kinetic and adiabatic electrons are presented. Although the similar ion temperature gradients with nonlinear upshift from linear critical gradients are sustained in quasi-steady states, parallel flows and radial electric fields are qualitatively different with kinetic electrons. [ABSTRACT FROM AUTHOR]

The elastic collision between two ortho-positronium (e.g. S = 1) atoms is studied using an ab-initio static exchange model (SEM) in the centre of mass (CM) frame by considering the system as a four-body Coulomb problem where all the Coulomb interaction terms in the direct and exchange channels are treated exactly. A coupled channel methodology in momentum space is used to solve Lippman-Schwinger equation following the integral approach. A new SEM code is developed in which the Born-Oppenheimer (BO) scattering amplitude acts as input to derive the SEM amplitude adapting the partial wave analysis. The s-, p- and d-wave elastic phase shifts and the corresponding partial cross-sections for the spin alignment S = 0, i.e., singlet (+) and S = 2, i.e., triplet (−) states are studied. An augmented Born approximation is used to include the contribution of higher partial waves more accurately to determine the total/integrated elastic cross-section ( σ), the quenching cross-section ( σ ) and ortho-to-para conversion ratio ( σ/ σ ). The effective range theory is used to determine the scattering lengths and effective ranges in the s-wave elastic scattering. The theory includes the non-adiabatic short-range effects due to exchange. [ABSTRACT FROM AUTHOR]