bluuebunny/crossref_metadata_2025 huggingface dataset:
First-principles study of electronic, optical and thermal transport properties of group III–VI monolayer MX (M = Ga, In; X = S, Se)
Authors: Wang Huimin , Qin Guangzhao , Yang Jiayue , Qin Zhenzhen , Yao Yagang , Wang Qiang , Hu Ming
Published: June 2019

Two-dimensional (2D) GaS, GaSe, and InSe were reported to be semiconductors and have been recently fabricated with potential applications in photoelectrics, where in-depth understanding from electronic structure is necessary. In addition, the thermal transport properties play a key role as to the thermal stability and the efficient heat dissipation for device operation, which are also necessary to be addressed. In this paper, we present a systematic first-principles study on the electronic, optical, and thermal transport properties for the representative group III–VI monolayer GaS, GaSe, and InSe. Our results indicate that monolayer GaS, GaSe, and InSe are semiconductors with an indirect bandgap. The predominant influence of interband transitions due to the large bandgap causes monolayer GaSe to possess the highest absorptivity along both “in-plane” and “out-of-plane” directions compared to the other two systems. Moreover, the lattice thermal conductivities (κL) of these materials are found to be inversely proportional to their average atomic mass, but the decrease in thermal conductivity from GaS to GaSe is negligible in comparison to that of GaSe to InSe with a nearly equivalent mass difference. It is found that the underlying mechanism lies in the larger phonon relaxation time of GaSe caused by weaker anharmonicity. Our study provides a comprehensive understanding of the inherent physical properties of monolayer GaS, GaSe, and InSe, which would benefit their future applications in photoelectrics.
Efficient construction of generalized master equation memory kernels for multi-state systems from nonadiabatic quantum-classical dynamics
Authors: Pfalzgraff William C. , Montoya-Castillo Andrés , Kelly Aaron , Markland Thomas E.
Published: June 2019

Methods derived from the generalized quantum master equation (GQME) framework have provided the basis for elucidating energy and charge transfer in systems ranging from molecular solids to photosynthetic complexes. Recently, the nonperturbative combination of the GQME with quantum-classical methods has resulted in approaches whose accuracy and efficiency exceed those of the original quantum-classical schemes while offering significant accuracy improvements over perturbative expansions of the GQME. Here, we show that, while the non-Markovian memory kernel required to propagate the GQME scales quartically with the number of subsystem states, the number of trajectories required scales at most quadratically when using quantum-classical methods to construct the kernel. We then present an algorithm that allows further acceleration of the quantum-classical GQME by providing a way to selectively sample the kernel matrix elements that are most important to the process of interest. We demonstrate the utility of these advances by applying the combination of Ehrenfest mean field theory with the GQME (MF-GQME) to models of the Fenna-Matthews-Olson (FMO) complex and the light harvesting complex II (LHCII), with 7 and 14 states, respectively. This allows us to show that the MF-GQME is able to accurately capture all the relevant dynamical time scales in LHCII: the initial nonequilibrium population transfer on the femtosecond time scale, the steady state-type trapping on the picosecond time scale, and the long time population relaxation. Remarkably, all of these physical effects spanning tens of picoseconds can be encoded in a memory kernel that decays only after ∼65 fs.
Piezoresistive behavior of amorphous carbon films for high performance MEMS force sensors
Authors: Ma Xin , Guo Peng , Tong Xiaoshan , Zhao Yulong , Zhang Qi , Ke Peiling , Wang Aiying
Published: June 2019

In this study, microelectromechanical systems (MEMS) force sensors based on H-free amorphous carbon (a-C) films with controlled piezoresistive behavior were fabricated by a facile magnetron sputtering technique. By adjusting the substrate bias voltage from 0 V (floating state) to –350 V, the gauge factor (GF) of the a-C film was modulated in the range of 1.4–12.1. Interestingly, the GF showed a strong dependence on the sp2 content and the sp2 cluster size of the film, which was consistent with the theory of thick film resistors. In addition, the sensitivity of a-C based MEMS force sensors reached 80.7 μV/V/N in the force range of 0–1.16 N, with a nonlinearity of approximately 1.3% full scale and good repeatability in over 5000 test cycles.
Scaling methods for accelerating kinetic Monte Carlo simulations of chemical reaction networks
Authors: Lin Yen Ting , Feng Song , Hlavacek William S.
Published: June 2019

Various kinetic Monte Carlo algorithms become inefficient when some of the population sizes in a system are large, which gives rise to a large number of reaction events per unit time. Here, we present a new acceleration algorithm based on adaptive and heterogeneous scaling of reaction rates and stoichiometric coefficients. The algorithm is conceptually related to the commonly used idea of accelerating a stochastic simulation by considering a subvolume λΩ (0 < λ < 1) within a system of interest, which reduces the number of reaction events per unit time occurring in a simulation by a factor 1/λ at the cost of greater error in unbiased estimates of first moments and biased overestimates of second moments. Our new approach offers two unique benefits. First, scaling is adaptive and heterogeneous, which eliminates the pitfall of overaggressive scaling. Second, there is no need for an a priori classification of populations as discrete or continuous (as in a hybrid method), which is problematic when discreteness of a chemical species changes during a simulation. The method requires specification of only a single algorithmic parameter, Nc, a global critical population size above which populations are effectively scaled down to increase simulation efficiency. The method, which we term partial scaling, is implemented in the open-source BioNetGen software package. We demonstrate that partial scaling can significantly accelerate simulations without significant loss of accuracy for several published models of biological systems. These models characterize activation of the mitogen-activated protein kinase ERK, prion protein aggregation, and T-cell receptor signaling.
Two single-reference approaches to singlet biradicaloid problems: Complex, restricted orbitals and approximate spin-projection combined with regularized orbital-optimized Møller-Plesset perturbation theory
Authors: Lee Joonho , Head-Gordon Martin
Published: June 2019

We present a comprehensive study of two single-reference approaches to singlet biradicaloids. These two approaches are based on the recently developed regularized orbital-optimized Møller-Plesset method (κ-OOMP2). The first approach is to combine Yamaguchi’s approximate projection (AP) scheme and κ-OOMP2 with unrestricted (U) orbitals (κ-UOOMP2). By capturing only essential symmetry breaking, κ-UOOMP2 can serve as a suitable basis for AP. The second approach is κ-OOMP2 with complex, restricted (cR) orbitals (κ-cROOMP2). Although its applicability is more limited due to the comparative rarity of cR solutions, κ-cROOMP2 offers a simple framework for describing singlet biradicaloids with complex polarization while removing artificial spatial symmetry breaking. We compare the scope of these two methods with numerical studies. We show that AP+κ-UOOMP2 and κ-cROOMP2 can perform similarly well in the TS12 set, a dataset that includes 12 data points for triplet-singlet gaps of several atoms and diatomic molecules with a triplet ground state. This was also found to be true for the barrier height of a reaction involving attack on a cysteine ion by a singlet oxygen molecule. However, we also demonstrate that in highly symmetric systems like C30 (D5h), κ-cROOMP2 is more suitable as it conserves spatial symmetry. Finally, we present an organic biradicaloid that does not have a κ-cROOMP2 solution in which case only AP+κ-UOOMP2 is applicable. We recommend κ-cROOMP2 whenever complex polarization is essential and AP+κ-UOOMP2 for biradicaloids without essential complex polarization but with essential spin-polarization.
Optical and electrical properties of two-dimensional palladium diselenide
Authors: Zhang George , Amani Matin , Chaturvedi Apoorva , Tan Chaoliang , Bullock James , Song Xiaohui , Kim Hyungjin , Lien Der-Hsien , Scott Mary C. , Zhang Hua , Javey Ali
Published: June 2019

Two-dimensional (2D) noble-metal dichalcogenides exhibit exceptionally strong thickness-dependent bandgaps, which can be leveraged in a wide variety of device applications. A detailed study of their optical (e.g., optical bandgaps) and electrical properties (e.g., mobilities) is important in determining potential future applications of these materials. In this work, we perform detailed optical and electrical characterization of 2D PdSe2 nanoflakes mechanically exfoliated from a single-crystalline source. Layer-dependent bandgap analysis from optical absorption results indicates that this material is an indirect semiconductor with bandgaps of approximately 1.37 and 0.50 eV for the monolayer and bulk, respectively. Spectral photoresponse measurements further confirm these bandgap values. Moreover, temperature-dependent electrical measurements of a 6.8-nm-thick PdSe2 flake-based transistor show effective electron mobilities of 130 and 520 cm2 V−1 s−1 at 300 K and 77 K, respectively. Finally, we demonstrate that PdSe2 can be utilized for short-wave infrared photodetectors. A room-temperature specific detectivity (D*) of 1.8 × 1010 cm Hz1/2 W−1 at 1 μm with a band edge at 1.94 μm is achieved on a 6.8-nm-thick PdSe2 flake-based photodetector.
Zero temperature coefficient of sound velocity in vitreous silicon oxynitride thin films
Authors: Nagakubo A. , Tsuboi S. , Kabe Y. , Matsuda S. , Koreeda A. , Fujii Y. , Ogi H.
Published: June 2019

Vitreous silicon oxide (v-SiO2) shows anomalous phonon properties such as the positive temperature coefficient of velocity (TCV). Variation of the Si–O–Si bond angle between SiO4 tetrahedrons has been recognized to be the key, but the origin of TCV still remains unclear. In this study, we controlled the bond angle by doping nitrogen and measured TCV of vitreous silicon oxynitride thin films with various nitrogen concentrations using picosecond ultrasonics. TCV significantly decreases by adding a small amount of nitrogen, and it shows positive to negative values as the nitrogen concentration increases. We evaluated the bond-angle change by Fourier-transform infrared spectroscopy, which decreases with the increase in the nitrogen content. We also find that the temperature rise in nondoped v-SiO2 decreases the bond angle, leading to an increase in the sound velocity. We then reveal theoretically that the bond-angle change dominates the origin of the positive TCV. This study indicates the existence of a zero-TCV single material, and we discover that the specific content of v-SiO1.71N0.19 achieves this.
A quantum-mechanical tier model for phonon-driven vibrational relaxation dynamics of adsorbates at surfaces
Authors: Bouakline F. , Fischer E. W. , Saalfrank P.
Published: June 2019

We present a quantum-mechanical tier model for vibrational relaxation of low-lying excited states of an adsorbate vibrational mode (system), coupled to surface phonons (bath), at zero temperature. The tier model, widely used in studies of intramolecular vibrational energy redistribution in polyatomics, is adapted here to adsorbate-surface systems with the help of an embedded cluster approach, using orthogonal coordinates for the system and bath modes, and a phononic expansion of their interaction. The key idea of the model is to organize the system-bath zeroth-order vibrational space into a hierarchical structure of vibrational tiers and keep therein only vibrational states that are sequentially generated from the system-bath initial vibrational state. Each tier is generated from the previous one by means of a successor operator, derived from the system-bath interaction Hamiltonian. This sequential procedure leads to a drastic reduction of the dimension of the system-bath vibrational space. We notably show that for harmonic vibrational motion of the system and linear system-bath couplings in the system coordinate, the dimension of the tier-model vibrational basis scales as ∼Nl×υ. Here, N is the number of bath modes, l is the highest-order of the phononic expansion, and υ is the size of the system vibrational basis. This polynomial scaling is computationally far superior to the exponential scaling of the original zeroth-order vibrational basis, ∼MN, with M being the number of basis functions per bath mode. In addition, since each tier is coupled only to its adjacent neighbors, the matrix representation of the system-bath Hamiltonian in this new vibrational basis has a symmetric block-tridiagonal form, with each block being very sparse. This favors the combination of the tier-model with iterative Krylov techniques, such as the Lanczos algorithm, to solve the time-dependent Schrödinger equation for the full Hamiltonian. To illustrate the method, we study vibrational relaxation of a D–Si bending mode, coupled via two- and (mainly) one-phonon interactions to a fully D-covered Si(100)-(2 × 1) surface, using a recent first-principles system-bath Hamiltonian. The results of the tier model are compared with those obtained by the Lindblad formalism of the reduced density matrix. We find that the tier model provides much more information and insight into mechanisms of vibration-phonon couplings at surfaces, and gives more reliable estimates of the adsorbate vibrational lifetimes. Moreover, the tier model might also serve as a benchmark for other approximate quantum-dynamics methods, such as multiconfiguration wavefunction approaches.
Segregation particles induced ultrahigh energy storage performances in BiMnO3 modified BaTiO3 films
Authors: Guo Fei , Jiang Ning , Yang Bo , Zhao Shifeng
Published: June 2019

Lead-free BiMnO3 modified BaTiO3 solid solution films are prepared by Sol-gel methods. An ultrahigh energy storage density of 94.1 J/cm3 and an efficiency of 84.51% are obtained, together with excellent frequency and thermal stability, in 0.92BaTiO3-0.08BiMnO3 solid solution films. The Jujube-Cake structure of the segregation particles in the films is suggested to improve the electric insulation, breakdown strength, and the maximum polarization, which are the key factors for energy storage performances in relaxor ferroelectrics. This work opens a route to improve the energy storage performances in solid solution films.
Amorphous and crystalline ices studied by dielectric spectroscopy
Authors: Plaga L. J. , Raidt A. , Fuentes Landete V. , Amann-Winkel K. , Massani B. , Gasser T. M. , Gainaru C. , Loerting T. , Böhmer R.
Published: June 2019

This work reports on frequency dependent ambient-pressure dielectric measurements of hyperquenched glassy water, ice IV, ice VI, as well as a CO2-filled clathrate hydrate, the latter featuring a chiral water network. The dipolar time scales and the spectral shapes of the loss spectra of these specimens are mapped out and compared with literature data on low-density and high-density amorphous ices as well as on amorphous solid water. There is a trend that the responses of the more highly dense amorphous ices are slightly more dynamically heterogeneous than those of the lower-density amorphous ices. Furthermore, practically all of the amorphous ices, for which broadband dielectric spectra are available, display a curved high-frequency wing. Conversely, the high-frequency flanks of the nominally pure ice crystals including ice V and ice XII can be characterized by an approximate power-law behavior. While the spectral shapes of the nominally pure ices thus yield some hints regarding their amorphicity or crystallinity, a comparison of their time scale appears less distinctive in this respect. In the accessible temperature range, the relaxation times of the crystalline ices are between those of low-density and high-density amorphous ice. Hence, with reference also to previous work, the application of suitable doping currently seems to be the best dielectric spectroscopy approach to distinguish amorphous from crystalline ices.
Effect of exciton transfer on recombination dynamics in vertically nonuniform GaAsSb epilayers
Authors: Zhang Bin , Qiu Weiyang , Chen Shula , Chen Pingping , Chen Weimin M , Buyanova Irina A. , Wang Xingjun
Published: June 2019

Low-temperature photoluminescence (PL), photoreflectance (PR), and temperature dependent time-resolved PL spectroscopies are employed to investigate optical emission processes and exciton dynamics in graded GaAsSb epilayers. The nonuniformity in the Sb composition along the growth direction is disclosed by low-temperature PL and PR measurements. Furthermore, significant differences in PL dynamics are found at low temperatures for the PL emissions originating from spatial regions with the low and high Sb compositions, with a fast decay and a slow rise at the early stage of the PL transient, respectively. This finding is attributed to exciton transfer from the low Sb region to the high Sb region. The obtained results are important for a general understanding of optical transitions and exciton/carrier dynamics in material systems with a graded alloy composition.
Guide to Crickets of Australia
Authors: Rentz David , Su You Ning
Published: June 2019

Cricket song is a sound of the Australian bush. Even in cities, the rasping calls signify Australia’s remarkable cricket biodiversity. Crickets are notable for a variety of reasons. When their population booms, some of these species become agricultural pests and destroy crop pastures. Some introduced species are of biosecurity concern. Other crickets are important food sources for native birds, reptiles and mammals, as well as domestic pets. Soon you might even put them in your cake or stir-fry, as there is a rapidly growing industry for cricket products for human consumption.
Featuring keys, distribution maps, illustrations and detailed colour photographs from CSIRO’s Australian National Insect Collection, A Guide to Crickets of Australia allows readers to reliably identify all 92 described genera and many species from the Grylloidea (true crickets) and Gryllotalpoidea (mole crickets and ant crickets) superfamilies. Not included are the Raspy Crickets (Gryllacrididae), King Crickets (Anostostomatidae) or the so-called ‘Pygmy Mole Crickets’ (Caelifera), which despite their common names are not related to true crickets. Natural history enthusiasts and professionals will find this an essential guide.
Soil carbon pools and enzyme activities in aggregate size fractions after seven years of conservation agriculture in a rice–wheat system
Authors: Sharma Sandeep , Vashisht Monika , Singh Yadvinder , Thind H. S.
Published: June 2019

Decline in soil organic carbon (SOC) due to intensive tillage and removal or burning of crop residues is considered a major threat to maintaining soil quality and meeting future challenges of food production at national and global scales. Adoption of conservation-agriculture practices (no till and residue retention) is necessary to promote soil structural stability and increases in SOC content and enzyme activities. We evaluated the impact of tillage and residue-management practices on yield, soil labile-C pools, aggregate stability and soil enzyme activities after seven cycles of a rice (Oryza sativa L.)–wheat (Triticum aestivum L.) system on the Indo-Gangetic Plain of India. Treatments included four combinations of tillage and crop establishment in rice (main plots), and three combinations of tillage and residue management in wheat (subplots). Irrespective of rice-establishment method, mean grain yield of no-till wheat with rice-residue mulch (NTW+RR) was 9% and 22% higher, respectively, than of conventional-till (CTW) or no-till wheat with no rice-residue mulch. Soil C pools (very labile, labile, less-labile and non-labile) were significantly higher under a no-till dry-seeded rice (NTDSR)–NTW+RR cycle than conventional-till puddled transplanted rice–CTW. Macro-aggregates (>0.25 mm) had higher labile C pools, glomalin content and enzyme activities than micro-aggregates. NTW+RR significantly increased soil C pools within both macro- and micro-aggregates. Compared with CTW, NTW+RR increased soil dehydrogenase, cellulase and alkaline phosphatase activities by 23%, 34% and 14%, and water-soluble organic C by 31%, and increased water-stable aggregates and mean-weight-diameter. NTDSR–NTW+RR increased SOC, enzyme activity, aggregate stability and wheat grain yield. Results indicated that soil labile-C pools across aggregate fractions were the most sensitive indicators of soil quality when determining the effects of changes in management practices. Furthermore, adoption of no till and residue retention may improve sustainability in rice–wheat systems of the Indo-Gangetic Plain.
Using the genetic characteristics of Neisseria gonorrhoeae strains with decreased susceptibility to cefixime to develop a molecular assay to predict cefixime susceptibility
Authors: Deng Xiaomeng , Allan-Blitz Lao-Tzu , Klausner Jeffrey D.
Published: June 2019

Background: In the last two decades, gonococcal strains with decreased cefixime susceptibility and cases of clinical treatment failure have been reported worldwide. Gonococcal strains with a cefixime minimum inhibitory concentration (MIC) ≥0.12 µg mL−1 are significantly more likely to fail cefixime treatment than strains with an MIC <0.12 µg mL−1. Various researchers have described the molecular characteristics of gonococcal strains with reduced cefixime susceptibility, and many have proposed critical molecular alterations that contribute to this decreased susceptibility. Methods: A systematic review of all published articles in PubMed through 1 November 2018 was conducted that report findings on the molecular characteristics and potential mechanisms of resistance for gonococcal strains with decreased cefixime susceptibility. The findings were summarised and suggestions were made for the development of a molecular-based cefixime susceptibility assay. Results: The penicillin-binding protein 2 (PBP2) encoded by the penA gene is the primary target of cefixime antimicrobial activity. Decreased cefixime susceptibility is conferred by altered penA genes with mosaic substitute sequences from other Neisseria (N.) species (identifiable by alterations at amino acid position 375–377) or by non-mosaic penA genes with at least one of the critical amino acid substitutions at positions 501, 542 and 551. Based on this review of 415 international cefixime decreased susceptible N. gonorrhoeae isolates, the estimated sensitivity for an assay detecting the aforementioned amino acid alterations would be 99.5% (413/415). Conclusions: Targeting mosaic penA and critical amino acid substitutions in non-mosaic penA are necessary and may be sufficient to produce a robust, universal molecular assay to predict cefixime susceptibility.
Decoding team and individual impact in science and invention
Authors: Ahmadpoor Mohammad , Jones Benjamin F.
Published: June 2019

Scientists and inventors increasingly work in teams, raising fundamental questions about the nature of team production and making individual assessment increasingly difficult. Here we present a method for describing individual and team citation impact that both is computationally feasible and can be applied in standard, wide-scale databases. We track individuals across collaboration networks to define an individual citation index and examine outcomes when each individual works alone or in teams. Studying 24 million research articles and 3.9 million US patents, we find a substantial impact advantage of teamwork over solo work. However, this advantage declines as differences between the team members’ individual citation indices grow. Team impact is predicted more by the lower-citation rather than the higher-citation team members, typically centering near the harmonic average of the individual citation indices. Consistent with this finding, teams tend to assemble among individuals with similar citation impact in all fields of science and patenting. In assessing individuals, our index, which accounts for each coauthor, is shown to have substantial advantages over existing measures. First, it more accurately predicts out-of-sample paper and patent outcomes. Second, it more accurately characterizes which scholars are elected to the National Academy of Sciences. Overall, the methodology uncovers universal regularities that inform team organization while also providing a tool for individual evaluation in the team production era.
The energetic basis for hydroxyapatite mineralization by amelogenin variants provides insights into the origin of
amelogenesis imperfecta
Authors: Tao Jinhui , Shin Yongsoon , Jayasinha Rajith , Buchko Garry W. , Burton Sarah D. , Dohnalkova Alice C. , Wang Zheming , Shaw Wendy J. , Tarasevich Barbara J.
Published: June 2019

Significance

Protein binding is important to many biological processes such as biomineralization, cell signaling, and enzyme interactions. We found that protein binding is key in explaining how single amino acid changes in amelogenin can lead to adverse effects on the biomineralization of hydroxyapatite (HAP) in tooth enamel. A normal amount of protein adsorption resulted in HAP formation and the enzymatic removal of protein from HAP surfaces by MMP20 for the wild-type amelogenin, rpM179. Excessive protein binding, however, inhibited HAP formation and slowed the removal of protein by MMP20 for T21I, P41T, and P71T single amino acid variants. Excessive protein binding may be an important factor in explaining how single amino acid variants cause the
amelogenesis imperfecta
phenotype in vivo.
Learning to predict the cosmological structure formation
Authors: He Siyu , Li Yin , Feng Yu , Ho Shirley , Ravanbakhsh Siamak , Chen Wei , Póczos Barnabás
Published: June 2019

Matter evolved under the influence of gravity from minuscule density fluctuations. Nonperturbative structure formed hierarchically over all scales and developed non-Gaussian features in the Universe, known as the cosmic web. To fully understand the structure formation of the Universe is one of the holy grails of modern astrophysics. Astrophysicists survey large volumes of the Universe and use a large ensemble of computer simulations to compare with the observed data to extract the full information of our own Universe. However, to evolve billions of particles over billions of years, even with the simplest physics, is a daunting task. We build a deep neural network, the Deep Density Displacement Model (

D

3

M

), which learns from a set of prerun numerical simulations, to predict the nonlinear large-scale structure of the Universe with the Zel’dovich Approximation (ZA), an analytical approximation based on perturbation theory, as the input. Our extensive analysis demonstrates that

D

3

M

outperforms the second-order perturbation theory (2LPT), the commonly used fast-approximate simulation method, in predicting cosmic structure in the nonlinear regime. We also show that

D

3

M

is able to accurately extrapolate far beyond its training data and predict structure formation for significantly different cosmological parameters. Our study proves that deep learning is a practical and accurate alternative to approximate 3D simulations of the gravitational structure formation of the Universe.
Cochlear partition anatomy and motion in humans differ from the classic view of mammals
Authors: Raufer Stefan , Guinan John J. , Nakajima Hideko Heidi
Published: June 2019

Significance

Basic properties of hearing such as its sensitivity and frequency tuning arise from the mechanical responses in the cochlea. Such responses have been measured extensively in the cochlear base of laboratory mammals, and our understanding of human cochlear mechanics is largely founded on the assumption that cochlear mechanics is similar in all mammals. Here we show that the anatomy and motion of the human cochlear partition differ in crucial ways from the generalized classic view of mammalian cochlear mechanics. Our results call into question this classic view. Establishing the features of human cochlear anatomy and function is important for understanding human hearing and for comparison with results from laboratory animals.
Nogo-A targeted therapy promotes vascular repair and functional recovery following stroke
Authors: Rust Ruslan , Grönnert Lisa , Gantner Christina , Enzler Alinda , Mulders Geertje , Weber Rebecca Z. , Siewert Arthur , Limasale Yanuar D. P. , Meinhardt Andrea , Maurer Michael A. , Sartori Andrea M. , Hofer Anna-Sophie , Werner Carsten , Schwab Martin E.
Published: June 2019

Significance

Patients suffering from ischemic strokes have limited therapeutic options and are often left with considerable disabilities. To promote neurological recovery, angiogenesis has been proposed as a promising therapeutic target. So far, experimental efforts to enhance vessel growth have almost exclusively focused on vascular growth factor supplementation; this approach has been shown not to be clinically viable due to hemorrhagic risks. Here, we pursued an alternative approach by targeting the guidance molecule Nogo-A, which has been recently shown to inhibit developmental central nervous system angiogenesis. Blockage of the Nogo-A pathway results in restoration of a mature vascular bed within the periinfarct zone. Moreover, we observe enhanced recovery-associated tissue responses and regain of motor functions that strongly correlate with vascular growth.
Atlastin-mediated membrane tethering is critical for cargo mobility and exit from the endoplasmic reticulum
Authors: Niu Liling , Ma Tianji , Yang Feng , Yan Bing , Tang Xiao , Yin Haidi , Wu Qian , Huang Yan , Yao Zhong-Ping , Wang Jifeng , Guo Yusong , Hu Junjie
Published: June 2019

Significance

In the early secretory pathway, newly synthesized proteins undergo folding and modifications and then leave the ER through COPII-coated vesicles. How these processes are coordinated and maintained are important but mostly unclear. We show here that ATL, a GTPase that connects ER tubules, controls ER protein mobility and regulates cargo packaging and coat assembly of COPII vesicles. The tethering and fusion activity by ATL likely maintains tension and other necessary parameters for COPII formation in ER membranes. These findings reveal a role of ER shaping in the early secretory pathway and provide insight into behaviors of ER exportation.
Creating the conditions for human division and structural inequality
Authors: Talib Nadira
Published: June 2019

While Singapore’s education system claims to implement meritocratic ideals, official statistics indicate that Malay students in Singapore have been underperforming when compared to other ethnic groups (MOE 2012). This statistical representation raises the possibility of a politically induced, systemic inequality as a point of investigation. To investigate this seeming contradiction between the rhetoric and practice of equal educational opportunity, this paper proposes a philosophical and analytical synthesis for examining the 1979 policy report that provides the fundamental basis for Singapore’s streaming education system. In examining this policy development, the analysis draws upon a combination of Foucault’s archaeological method and Critical Discourse Analysis as a way of understanding conditions that made possible the continuous re-construction of new but unequal representation of learners. The findings suggest that complex relations between capability identification, justice, and ethics set the conditions for the appearance and transformation of subject positions necessary to legitimise unequal structural access.
The detection of nitro compounds vapor using sensors based on MIS-structures manufactured by laser deposition
Authors: Etrekova M O , Litvinov A V , Mikhailov A A
Published: June 2019

The conditions of the detection of nitro compounds vapors was investigated using the trinitrotoluene as an example. The detection method consists of pyrolysis and later registration by the MIS-sensor of gaseous products of thermal decomposition . It was shown that the offered method allows to achieve the detection limit of 1·10-12 g/cm3 (particles – 1 ng) with respect to the vapors of trinitrotoluene.
Hydrodynamic processes in fused quartz under the action of laser radiation
Authors: Efremov V P , Kiverin A D , Yakovenko I S
Published: June 2019

The paper analyzes numerically the hydrodynamic processes developing inside the fused quartz under the action of intense laser impulses. Depending on laser intensity two basic regimes are obtained and described in details. At low intensities, the slow regime driven by the heat transfer is observed. Herewith, the fracture took place in the heated region before the phase transition. At higher intensities, the high-speed propagation regime is established characterized by the fracture events exactly at the interfacial boundary between the hot plasma and condensed phase. The propagation of absorption wave coupled with the fracture wave is limited by the value of sound speed in the hot plasma, which determines the expansion of plasma into the spallation region ahead of the absorption front. The proposed model of the process agrees well with the recent experimental data, in particular with the characteristic velocity scales.
Analysis of Influence of Seismic Oscillations on Precision Laser Plants’ Work
Authors: Gubskiy K , Sorokin S , Reshetova M , Reshetov V
Published: June 2019

The seismic situation in a number of rooms of the NRNU MEPhI, including the Laboratory Building, where the construction of the multifunctional laser complex ELF is planned, is studied. Estimations of seismic and vibrational noise at the main and isolated parts of the basement of the room that hosts the laser complex are obtained.
Unified discrete mechanics II: The space and time symmetric hyperincursive discrete Klein-Gordon equation bifurcates to the 4 incursive discrete Majorana real 4-spinors equations
Authors: Dubois Daniel M
Published: June 2019

This paper begins with the formalization of the second order hyperincursive discrete Klein-Gordon equation. The temporal second order hyperincursive discrete Klein-Gordon equation is similar to the time-symmetric hyperincursive discrete harmonic oscillator and so bifurcates into a group of 4 incursive discrete real equations of first order. In this group, two equations are the discrete time reverse of the two other equations, giving an oscillator and an anti-oscillator. Firstly, the discrete Klein-Gordon equation, with one space dimension (1D), bifurcates to 4 first order incursive discrete equations that we called the Dubois-Ord-Mann real 4-spinors equations because Ord and Mann obtained the same equations from a stochastic method. Secondly, we generalize to three spatial dimensions (3D) these discrete Dubois-Ord-Mann equations. These 4 discrete equations are then transformed to real partial differential equations which can be written under the generic form of the Dirac quantum 4-spinors equation. Thirdly, we consider a change in the order of space variables and a change of indexes of the functions of the Dubois-Ord-Mann equations. With these changes we obtain the original real 4-Spinors Majorana partial differential equations. Also we obtain the 4 incursive discrete Majorana real equations.
Unified discrete mechanics III: the hyperincursive discrete Klein-Gordon equation bifurcates to the 4 incursive discrete Majorana and Dirac equations and to the 16 Proca equations
Authors: Dubois Daniel M
Published: June 2019

This paper presents the second order hyperincursive discrete Klein-Gordon equation in three spatial dimensions. This discrete Klein-Gordon equation bifurcates to 4 incursive discrete equations. We present the 4 incursive discrete Dubois-Ord-Mann real equations and the corresponding first order partial differential equations. In three spatial dimensions, the two oscillators given by these equations are now entangled with one spatial dimension, so the 4 equations form a whole. Then, we deduce the 4 incursive discrete Dubois-Majorana real equations and the corresponding first order partial differential equations. Next, these Dubois-Majorana real equations are presented in the generic form of the Dirac 4-spinors equation. In making a change in the indexes of the 4 functions in the Dubois-Majorana equations, the 4 first order partial differential equations become identical to the Majorana real 4-spinors equations. Then, we demonstrate that the Majorana equations bifurcate to the 8 real Dirac first order partial differential equations that are transformed to the original Dirac 4-spinors equations. Then, we give the 4 incursive discrete Dirac 4-spinors equations. Finally, we show that there are 16 discrete functions associated to the space and time symmetric discrete Klein-Gordon equation. This is in agreement with the Proca thesis on the 16 components of the Dirac wave function in 4 groups of 4 equations. In this paper, we restricted our derivation of the Majorana and Dirac equations to the first group of 4 equations depending on 4 functions.
Wildfire suppression technology: Exploration for a directed energy beam (DEB) attenuating electron transfer by cyclical vacuum subduction of dioxygen dication species, O2
2+
Authors: Amoroso Richard L , Giandinoto Salvatore , Karam Sabah E
Published: June 2019

Modeling wildfire suppression technology, inspired by Einstein’s long quest for a final theory, is based on a Unified Field Mechanical (UFM) Ontological-Phase Topological Field Theory (OPTFT) derived from modified M-theory, parameters of the Wheeler-Feynman-Cramer Transactional Interpretation, with combined extensions of a de Broglie-Bohm Implicate Order super-quantum potential as a unified field force of coherence control factor. The device is multiphasic. Operationally, O2 electron transfer attenuation occurs by nonlocal matter-wave phase adduction/subduction interference nodes in dynamic-static Casimir-Polder resonant interactions pertinent to bumps and holes within a covariant polarized Dirac vacuum as the most salient feature of dioxygen dication, O2
2+ coupling to mirror symmetric nonlocal antispace (vacuum), rather than neutral molecular species in local 3-space as demonstrated in experimental studies of dioxygen dication, O2
2+. Additionally, beam emission requires a new dual class of nonlocal OCHRE (Oscillation Coupled Helicoid Resonance Emission) in tandem with localized OCRET (Optically Controlled Resonance Energy Transfer) to produce ballistic-like conduction of vacuum energy by the summation of cyclical resonant incursive oscillations within the structure of cellular Least Units tessellating spacetime as a means of mediating the additional dimensionality (XD) of brane topological phase transitions in the Bulk. Finally, device operation requires an M-theoretic form of scalable universal quantum computing (UQC), a paradigm shift beyond confines of the locality-unitarity basis of presently standard Copenhagen quantum theory.
A new quantum - relativistic model of tachyons
Authors: Caligiuri Luigi Maxmilian
Published: June 2019

The possible existence of tachyons, namely hypothetical particles always moving faster than light in vacuum, is still controversial due to the common belief they would violate the principle of macroscopic causality, despite their existence is not forbidden, in principle, by the Einstein’s Special Theory of Relativity. Indeed, the main difficulties with tachyons are rather related to other two questions: their expected imaginary rest mass and the lack of a physical mechanism able to explain their existence especially from the standpoint of quantum theory. In this paper we discuss a novel physical mechanism, based on QED coherence in matter and on a reformulation of Special Theory of Relativity in the space-like region, able to explain a possible origin of tachyons as well as their real-value rest mass, ultimately related to the coherent dynamics of quantum vacuum.
Review of the time-symmetric hyperincursive discrete harmonic oscillator separable into two incursive harmonic oscillators with the conservation of the constant of motion
Authors: Dubois Daniel M
Published: June 2019

This paper deals with a review of the properties of the hyperincursive discrete harmonic oscillator separable into two incursive discrete harmonic oscillators. We begin with a presentation step by step of the second order discrete harmonic oscillator. Then the 4 incursive discrete equations of the hyperincursive discrete harmonic oscillator are presented. The constants of motion of the two incursive discrete harmonic oscillators are analyzed. After that, we give a numerical simulation of the incursive discrete harmonic oscillator. The numerical values correspond exactly to the analytical solutions. Then we present the hyperincursive discrete harmonic oscillator. And we give also a numerical simulation of the hyperincursive discrete harmonic oscillator. The numerical values correspond also to the analytical solutions. Finally, we demonstrate that a rotation on the position and velocity variables of the incursive discrete harmonic oscillators gives rise to a pure quadratic expression of the constant of motion which is an ellipse. This result is fundamental because it gives an explanation of the effect of the discretization of the time in discrete physics. The information obtained from the incursive and hyperincursive discrete equations is richer than the information obtained by continuous physics. In conclusion, we have shown the temporal discretization of the harmonic oscillator produces a rotation similarly to the formalism of the special relativity dealing with rotations.
Magnetic monopole as the shadow side of the electric charge
Authors: Krasnoholovets Volodymyr
Published: June 2019

It is shown that a magnetic monopole appears as the tension state of the primary electric charge at its motion through each section of the path equal to the particle’s de Broglie wavelength. This conclusion is followed from a submicroscopic consideration of particles and their motion in the framework of the theory of physical space in the form of a tessellattice developed by Michel Bounias and the author. The periodical change of the particle’s charged state to its monopole state can easily be introduced in the conventional Maxwell equations and the magnetic monopole automatically shows up in the structure of Maxwell’s equations. The monopole is also presented in any quark system as a quark obeys dynamics that are also characterized by the appropriate de Broglie wavelength and hence the electric charge changes periodically to the magnetic monopole. A (anti)neutrino emerges as the typical electron’s monopole. When the charged particle becomes the monopole, it also loses its mass (the mass passes to the particle’s inerton cloud) and thus the neutrino is a massless particle, or more correctly massless monopole.
LIGO: The hypothesis of photons with non-zero rest mass
Authors: Marchal Christian
Published: June 2019

This study is done under the following assumptions: A) The results presented in the two relativistic works of Henri Poincaré “Sur la dynamique de l’électron” [1,2] are true. B) the “second principle” of Einstein, the constancy of the velocity of light, in “Zür Elektrodynamik der bewegten Körper” [4)], is not necessarily true and the photons can have an extremely small but non-zero rest mass mo. Of course all photons will be considered as identical, an already common assumption for electrons, for protons and for all particles. In these conditions are analyzed the small modifications of the aberration of stars, of the Doppler-Fizeau effect, of the Maxwell equations for the propagation of electromagnetic fields, etc. Some test observations and experiments are proposed. The photon-photon interaction is analyzed. It may have very large consequences in astronomy and cosmology.
Lorentz violation and quantum mechanics
Authors: Petrucci Andrea.
Published: June 2019

We report and discuss the results of double-slit-like experiments in the infrared range, which evidence an anomalous behaviour of photon systems under particular (energy and space) constraints. These outcomes apparently disagree both with standard quantum mechanics (Copenhagen interpretation) and with classical and quantum electrodynamics. Possible interpretations can be given in terms of either the existence of de Broglie–Bohm pilot waves associated to photons, and/or the violation of local Lorentz invariance (LLI). We put forward an intriguing hypothesis about the possible connection between these seemingly unrelated points of view by assuming that the pilot wave of a photon is, in the framework of LLI violation, a local deformation of the flat Minkowski spacetime.
A first step in evolving quantum cosmology
Authors: Seshavatharam U. V. S. , Lakshminarayana S.
Published: June 2019

Implementing Mach’s principle and Planck scale simultaneously in entire cosmic evolution can be considered as a first step in quantum cosmology. In this context, we propose a simple model of quantum cosmology without dark energy. Our assumptions are: 1) Universe is a quantum gravitational object. 2) Planck scale and Mach’s principle play a combined role in entire cosmic evolution. 3) Cosmic thermal wavelength is inversely proportional to ordinary matter density ratio. 4) Ordinary matter density ratio and dark matter density ratio play a combined role in estimating cosmic expansion velocity. 5) Critical energy density and dark energy density are equal in magnitude and physically there exists no dark energy.
Quantum particle, light clock or heavy beat box?
Authors: Mark Martin B van der
Published: June 2019

A standing wave of light inside a cavity, while observed from a moving frame, is seen to have a spatial beat of precisely the same nature as that of the de Broglie wave of a quantum particle. The structural forces that hold together the cavity against the internal radiation pressure are compared to the so-called Poincaré stresses inside an elementary particle, as are required for the particle’s stability. This seems to work best if the cavity is non-rigid and hence is itself oscillating, coupled to the radiation inside.
A new linear theory of light and matter
Authors: Williamson John G.
Published: June 2019

A new theory is proposed with similar form and mechanics to the Dirac equation, but where the rest-mass is introduced in a more fundamental way. The new theory proves to encompass and extend classical electromagnetism, and reduce to it exactly in the field only case. A sharpening of the principle of relativity allows fully relativistic field only solutions, which take on some of the properties more usually associated with quantised states. The extended theory has four new solutions which exhibit a non-zero electric field divergence and a double-covering symmetry. These are necessarily charged, essentially fermionic states, two with positive and two with negative charge, differing by an inner spin symmetry. The new configurations are identified with the spin “up” and spin “down” electron and positron.
Arctic protective materials based on complex oxides of titanium
Authors: Sologubova I A , Kotvanova M K , Pavlova S S
Published: June 2019

This paper presents the components and method for obtaining an effective protective coating. The coating has chemical and thermal stability in a wide range of temperatures, and has good mechanical characteristics. It was found that one of the important factors determining the properties of the coating is the degree of dispersion of powders of the starting materials. The optimal average particle size is 60 nm.
Carbohydrate-deficient transferrin: utility of HPLC in handling atypical samples uninterpretable by capillary electrophoresis
Authors: Veronesi Agnese , Cariani Elisabetta , Trenti Tommaso , Rota Cristina
Published: June 2019

HPLC retesting allowed to resolve about half of the most common CDT patterns uninterpretable by CE. The usefulness of this approach should be evaluated in the specific context of each laboratory.