bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermodynamics of complex plasmas with two different sorts of macroions
Authors: Martynova I A , Iosilevskiy I L 
Published: July 2020

Abstract
Three-component electroneutral systems of finite-size classical macroions with two different charge numbers Z
1 ≫ 1 and Z
2 ≫ 1 and point-like oppositely charged microions are analyzed. Free energy of a mixture of two sorts of macroions is estimated within the Wigner–Seitz cells approximation. The non-linear screening effect is taken into account via the Poisson–Boltzmann approximation within the both cells. The equality of microions pressures at the boundary between the co-existing cells with the different sorts of macroions is used as an equilibrium condition. The difference between the total Helmholtz free energy in equilibrium is shown in comparison with the situation when the Wigner–Seitz cells with macroions with the different charges have the same volumes.
Electric field influence on dust particle dynamics in dust vortices
Authors: Izvekova Yu N , Popel S I 
Published: July 2020

Abstract
We study dust vortices called dust devils and dynamics of dust in this structures. Dust devils are well formed relatively short-lived vortices that can appear over well heated surfaces like deserts and are clearly visible due to large amount of dust raised. Dust particles rotating in a flow bump and scrape each other and as a result particles obtain electric charges. Space separation of particles with opposite charges leads to generation of macroscopic electric field. We simulate dust dynamics with taking into account the electric field of the vortex.
Relationship between the dust-acoustic soliton parameters and the Debye radius
Authors: Trukhachev F M , Petrov O F , Vasiliev M M , Tomov A V 
Published: July 2020

Abstract
Based on the analysis of the dusty-acoustic soliton properties, a simple technique for estimating the Debye radius is proposed. It is shown that the Debye radius is approximately equal to 1–1/3 of the width of the soliton density profile, which can be easily determined from the analysis of photographs of a dust cloud.
Dynamics of motion of particles with a modified surface in a dusty plasma monolayer
Authors: Vasiliev M M , Kononov E A , Arkar K , Petrov O F 
Published: July 2020

Abstract
The results of the analysis of the mean square displacement and the trajectories of moving polymer particles with a modified surface in a dusty plasma monolayer under the influence of laser radiation are presented. It has been revealed that the dynamics of particle motion in a monolayer consists of three modes: finite motion within confinement, Brownian motion, and combined directional chaotic motion. The results of the analysis of linear displacement along and across the direction of motion of dust particles at various values of the laser radiation power are presented too. It has been shown experimentally that polymer particles with a modified surface are active Brownian particles and their activity grows with increasing laser radiation power.
About the mechanism of modification of melamine formaldehyde particles in dusty plasmas
Authors: Karasev V Yu , Polischuk V A , Dzlieva E S , Pavlov S I , Gorbenko A P 
Published: July 2020

Abstract
The article presents the previously obtained results of the modification of spherical microparticles of melamine-formaldehyde injected as a dust component of complex plasma formed in stratified glow discharge in neon. Particular attention is paid to changing the particle size depending on the residence time in the plasma. A mechanism is proposed for heating particles by ion flow sustaining a stable charge of their surface. Calculations of the heat balance are presented, confirming the results obtained in the experiment.
Comparison of megaampere channel temperature value measured by different methods at its maximal contraction in high density hydrogen
Authors: Bogomaz A A , Pinchuk M E , Budin A V , Leks A G , Sakan N M 
Published: July 2020

Abstract
Comparison of discharge channel temperature in gaseous hydrogen of high density with current amplitude of ~ 1 MA at initial gas pressure of 5–7 MPa, determined by two methods, was done under stage of its maximal contraction. In the first case determination of the temperature value of 72–73 eV was made by intensity of soft x-ray radiation from the channel for experiments with current amplitude of 1.1–1.5 MA. The estimation of the temperature on the basis of the data received by magnetic probe method and specified electric characteristics of the channel was of ≈ 140 eV for experiment with initial gas pressure of 5 MPa at current amplitude of 0.93 MA. The temperature determination by the last procedure has small accuracy caused by the limitation of the magnetic probe technique in determination of the channel contraction ratio and some assumptions for near-electrode voltage drops calculations by this way. Apparently, the channel temperature in stage of maximal contraction is of ~ 100 eV.
Soft x-ray source based on the point Z-pinch for pulse radiography
Authors: Artyomov A P , Chaikovsky S A , Rousskikh A G , Fedunin A V 
Published: July 2020

Abstract
This article presents the study of the influence of the cathode material of a plasma injector on the parameters of the x-ray source of a point Z-pinch (PZ-pinch). The experiments were carried out on the compact pulse power radiograph PR-PZP-M1 (210 kA, 220 ns). The new type of the plasma injector based on a ceramic insulator and a composite cathode is developed and tested in the experiments. PZ-pinches based on tin, silver and gold were studied. It was shown that tin is the most applicable material to the PZ-pinch formation in terms of radiography. The PZ-pinch mass optimization has been carried out to obtain the brightest x-ray source with minimum sizes. The achieved x-ray source diameter is 12 ± 3 μm, height is 18 ± 5 μm in the spectral range hν = 1–3 keV.
Radiation energy losses in a single chamber three phase plasma torch with rod electrodes
Authors: Dudnik Yu D , Kovshechnikov V B , Safronov A A , Kuznetsov V E , Shiryaev V N , Vasilieva O B 
Published: July 2020

Abstract
The paper deals with the results of the study of the plasma energy loss in a chamber of the three phase alternating current arc plasma torch at pressures above atmospheric. It is shown that the loss due to radiation takes the main share. A time-averaged estimation of the radiation power per unit length of the arcs and its dependence on pressure was obtained based on the results of calorimetric measurements of the heat flux into the end part of the plasma torch. The dependence of the fraction of energy loss by radiation versus the total loss in the plasma torch chamber depending on the pressure and gas flow rate are presented. The dependence of the efficiency of the plasma torch versus the gas flow rate and pressure is also given. Studies were conducted on a plasma torch over the power range from 50 to 200 kW. The working gas was nitrogen.
Verification of experimental studies of pulsed plasma accelerators
Authors: Shurupov A V , Shurupov M A , Zavalova V E , Mashtakov A V , Kozlov A V , Kozlov A A , Gusev A N , Shurupova N P 
Published: July 2020

Abstract
Explosive-magnetic generators (EMGs) unlike capacitive storages (CSs), as a rule, have growing power. The effective operation of pulsed plasma loads, such as pulsed plasma accelerators (PPAs), plasma foci, plasma breakers, etc, can be provided at realization of the mentioned advantage of EMG as a power source. A technique of laboratory experiments with PPA is presented in this paper. The experiments with PPA powered by CS precede the explosive experiment with EMG. The dependencies of the load operation modes on the start parameters are determined by the analysis of the experimental data. They included the dynamics of the inductance and the position of the current shell inside the PPA. The technique allows reducing the number of expensive explosive experiments and supplements the database of nonlinear dependencies of the load parameters under various amplitudes of the current pulse that is important for mathematical modeling. The technique based on experiments together with the estimations allowed solving the problem of matching of non-linear loads type PPA with EMG. Thus, the productivity of experiments with EMG increases greatly. The developed technique can be adapted to a wide class of nonlinear loads.
Study of the discharge with a liquid cathode with organic impurities
Authors: Chistolinov A V , Yakushin R V , Sargsyan M A , Khromov M A , Perfilieva A V 
Published: July 2020

Abstract
Dynamics of the discharge with a liquid cathode was studied using the method of high-speed visualization. The video data was compared with the emission spectra of the discharge plasma. Electrical parameters of the discharge were measured. The effect of organic impurities in the solution on the discharge parameters was investigated.
Impacts of the Arctic-midlatitude teleconnection on wintertime seasonal climate forecasts
Authors: Jung Euihyun , Jeong Jee-Hoon , Woo Sung-Ho , Kim Baek-Min , Yoon Jin-Ho , Lim Gyu-Ho 
Published: July 2020

Abstract
The impact of the Arctic on midlatitude weather and climate is still in scientific debate. The observation-based analysis, however, shows frequent concurrences of Arctic warming with extreme cold in the midlatitudes, and vice versa. This teleconnection could aid in seasonal climate forecasts for the midlatitudes. This study assessed the forecast skill of Arctic temperature and the Arctic-midlatitude teleconnection patterns in operational seasonal climate forecast models based on their wintertime forecast archives. Further, the impact of the Arctic-midlatitude teleconnection on the midlatitude forecast skill is evaluated. The results revealed that most climate forecast models have the capability to simulate the overall pattern of Arctic-midlatitude teleconnection for both the eastern Eurasian and North American regions. However, this is little converted to practical forecast skill in midlatitude likely due to poor capabilities in forecasting Arctic temperatures. Idealized analysis (assuming a perfect forecast of Arctic temperature) showed that considerable forecasting improvements could be achieved, and further improvements are possible with accurate simulations of the Arctic and its teleconnection patterns. These results highlight the importance of better predictions of the Arctic conditions in seasonal forecasts that are not just limited to their own region but extend to midlatitude weather and climate as well.
Mapping pervasive selective logging in the south-west Brazilian Amazon 2000–2019
Authors: Hethcoat M G , Carreiras J M B , Edwards DP , Bryant R G , Peres C A , Quegan S 
Published: July 2020

Abstract
Tropical forests harbour the highest biodiversity on the planet and are essential to human livelihoods and the global economy. However continued loss and degradation of forested landscapes, coupled with a rapidly rising global population, is placing incredible pressure on forests globally. The United Nations has developed the Reducing Emissions from Deforestation and forest Degradation (REDD +) programme in response to the challenges facing tropical forests and in recognition of the role they can play in climate mitigation. REDD + requires consistent and reliable monitoring of forests, however, national-level methodologies for measuring degradation are often bespoke and, because of an inability to track degradation effectively, the majority of countries combine reporting for deforestation and forest degradation into a single value. Here, we extend a recent analysis that enabled the detection of selective logging at the scale of a logging concession to a regional-scale estimation of selective logging activities. We utilized logging records from across Brazil to train a supervised classification algorithm for detecting logged pixels in Landsat imagery then predicted the extent of logging over a 20 year period throughout Rondônia, Brazil. Approximately one-quarter of the forested lands in Rondônia were cleared between 2000 and 2019. We estimate that 11.0% of the forest area present in 2000 had been selectively logged by 2019, comprising >11 500 km2 of forest. In general, rates of selective logging were twice as high in the first decade relative to the last decade of the period. Our approach is a considerable advance in developing an operationalized selective logging monitoring system capable of detecting subtle forest disturbances over large spatial scales.
Inferring ground-level nitrogen dioxide concentrations at fine spatial resolution applied to the TROPOMI satellite instrument
Authors: Cooper Matthew J , Martin Randall V , McLinden Chris A , Brook Jeffrey R 
Published: July 2020

Abstract
Satellite-based estimates of ground-level nitrogen dioxide (NO2) concentrations are useful for understanding links between air quality and health. A longstanding question has been why prior satellite-derived surface NO2 concentrations are biased low with respect to ground-based measurements. In this work we demonstrate that these biases are due to both the coarse resolution of previous satellite NO2 products and inaccuracies in vertical mixing assumptions used to convert satellite-observed tropospheric columns to surface concentrations. We develop an algorithm that now allows for different mixing assumptions to be used based on observed NO2 conditions. We then apply this algorithm to observations from the TROPOMI satellite instrument, which has been providing NO2 column observations at an unprecedented spatial resolution for over a year. This new product achieves estimates of ground-level NO2 with greater accuracy and higher resolution compared to previous satellite-based estimates from OMI. These comparisons also show that TROPOMI-inferred surface NO2 concentrations from our updated algorithm have higher correlation and lower bias than those found using TROPOMI and the prior algorithm. TROPOMI-inferred estimates of the population exposed to NO2 conditions exceeding health standards are at least three times higher than for OMI-inferred estimates. These developments provide an exciting opportunity for air quality monitoring.
Hydrogen evolution on non-metal oxide catalysts
Authors: Rhatigan Stephen , Michel Marie-Clara , Nolan Michael 
Published: July 2020

Abstract
Water splitting to produce hydrogen gas, using renewably produced electricity (electrocatalysis) or by direct conversion of solar energy (photocatalysis), is a strategy that addresses key environmental and energy challenges. The overall water splitting reaction proceeds as two half reactions, namely the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), each of which require catalysts specifically tailored to maximize efficiency. The benchmark catalysts for the HER are noble metals. However, their expense and rarity makes them economically unfeasible for large-scale H2 production from water. Consequently, there are considerable efforts to find cheap, abundant materials that can efficiently catalyze the HER. Over the last decade, metal chalcogenides and phosphides have emerged as promising candidates for HER. In this review article, we discuss a selection of the multitude of studies and materials in these two classes of catalyst to give a flavor of the relevant developments and properties of these materials. In addition to the selection of catalyst materials, preparation and structuring are playing a strong role in enhancing HER and overcoming fundamental challenges. The role of modeling in the performance of HER catalysts is also discussed and we end with a short perspective on the key attributes of a good HER catalyst.
RecBic: a fast and accurate algorithm recognizing trend-preserving biclusters
Authors: Liu Xiangyu , Li Di , Liu Juntao , Su Zhengchang , Li Guojun 
Published: July 2020

Abstract

Motivation
Biclustering has emerged as a powerful approach to identifying functional patterns in complex biological data. However, existing tools are limited by their accuracy and efficiency to recognize various kinds of complex biclusters submerged in ever large datasets. We introduce a novel fast and highly accurate algorithm RecBic to identify various forms of complex biclusters in gene expression datasets.

Results
We designed RecBic to identify various trend-preserving biclusters, particularly, those with narrow shapes, i.e. clusters where the number of genes is larger than the number of conditions/samples. Given a gene expression matrix, RecBic starts with a column seed, and grows it into a full-sized bicluster by simply repetitively comparing real numbers. When tested on simulated datasets in which the elements of implanted trend-preserving biclusters and those of the background matrix have the same distribution, RecBic was able to identify the implanted biclusters in a nearly perfect manner, outperforming all the compared salient tools in terms of accuracy and robustness to noise and overlaps between the clusters. Moreover, RecBic also showed superiority in identifying functionally related genes in real gene expression datasets.

Availability and implementation
Code, sample input data and usage instructions are available at the following websites. Code: https://github.com/holyzews/RecBic/tree/master/RecBic/. Data: http://doi.org/10.5281/zenodo.3842717.

Supplementary information
Supplementary data are available at Bioinformatics online.
TE-greedy-nester: structure-based detection of LTR retrotransposons and their nesting
Authors: Lexa Matej , Jedlicka Pavel , Vanat Ivan , Cervenansky Michal , Kejnovsky Eduard 
Published: July 2020

Abstract

Motivation
Transposable elements (TEs) in eukaryotes often get inserted into one another, forming sequences that become a complex mixture of full-length elements and their fragments. The reconstruction of full-length elements and the order in which they have been inserted is important for genome and transposon evolution studies. However, the accumulation of mutations and genome rearrangements over evolutionary time makes this process error-prone and decreases the efficiency of software aiming to recover all nested full-length TEs.

Results
We created software that uses a greedy recursive algorithm to mine increasingly fragmented copies of full-length LTR retrotransposons in assembled genomes and other sequence data. The software called TE-greedy-nester considers not only sequence similarity but also the structure of elements. This new tool was tested on a set of natural and synthetic sequences and its accuracy was compared to similar software. We found TE-greedy-nester to be superior in a number of parameters, namely computation time and full-length TE recovery in highly nested regions.

Availability and implementation
http://gitlab.fi.muni.cz/lexa/nested.

Supplementary information
Supplementary data are available at Bioinformatics online.
Improving Decision Making in Empiric Antibiotic Selection (IDEAS) for Gram-negative Bacteremia: A Prospective Clinical Implementation Study
Authors: Elligsen Marion , Pinto Ruxandra , Leis Jerome A , Walker Sandra A N , Daneman Nick , MacFadden Derek R 
Published: July 2020

Abstract

Background
Timely selection of adequate empiric antibiotics has become increasingly difficult due to rising resistance rates and the competing desire to apply antimicrobial stewardship (AMS) principles. Individualized clinical prediction models offer the promise of reducing broad-spectrum antibiotic use and preserving/improving adequacy of treatment, but few have been validated in the clinical setting.

Methods
Multivariable models were used to predict the probability of susceptibility for gram-negative (GN) bacteria in bloodstream infections (bacteremia) to ceftriaxone, ciprofloxacin, ceftazidime, piperacillin-tazobactam, and meropenem. The models were combined with existing resistance-prediction methods to generate optimized and individualized suggestions for empiric therapy that were provided to prescribers by an AMS pharmacist. De-escalation of empiric antibiotics and adequacy of therapy were analyzed using a quasi-experimental design comparing two 9-month periods (pre- and postintervention) at a large academic tertiary care institution.

Results
Episodes of bacteremia (n = 182) were identified in the preintervention and postintervention (n = 201) periods. Patients who received the intervention were more likely to have their therapy de-escalated (29 vs 21%; aOR = 1.77; 95% CI, 1.09–2.87; P = .02). The intervention also increased the proportion of patients who were on the narrowest adequate therapy at the time of culture finalization (44% in the control and 55% in the intervention group; aOR = 2.04; 95% CI, 1.27–3.27; P = .003). Time to adequate therapy was similar in the intervention and control groups (5 vs 4 hours; P = .95).

Conclusions
An AMS intervention, based on individualized predictive models for resistance, can influence empiric antibiotic selections for GN bacteremia to facilitate early de-escalation of therapy without compromising adequacy of antibiotic coverage.
Severe Acute Respiratory Syndrome Coronavirus 2 Antibody Prevalence in Blood in a Large School Community Subject to a Coronavirus Disease 2019 Outbreak: A Cross-sectional Study
Authors: Torres Juan Pablo , Piñera Cecilia , De La Maza Verónica , Lagomarcino Anne J , Simian Daniela , Torres Bárbara , Urquidi Cinthya , Valenzuela María Teresa , O’Ryan Miguel 
Published: July 2020

AbstractBackgroundA severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak affecting 52 people from a large school community in Santiago, Chile, was identified (12 March) 9 days after the first case in the country. We assessed the magnitude of the outbreak and the role students and staff played using self-administered antibody detection tests and a self-administered survey.MethodsThe school was closed on 13 March, and the entire community was placed under quarantine. We implemented a home-delivery, self-administered, immunoglobin (Ig) G/IgM antibody test and survey to a classroom-stratified sample of students and all staff from 4–19 May. We aimed to determine the overall seroprevalence rates by age group, reported symptoms, and contact exposure, and to explore the dynamics of transmission.ResultsThe antibody positivity rates were 9.9% (95% confidence interval [CI], 8.2–11.8) for 1009 students and 16.6% (95% CI, 12.1–21.9) for 235 staff. Among students, positivity was associated with a younger age (P = .01), a lower grade level (P = .05), prior real-time polymerase chain reaction (RT-PCR) positivity (P = .03), and a history of contact with a confirmed case (P &lt; .001). Among staff, positivity was higher in teachers (P = .01) and in those previously RT-PCR positive (P &lt; .001). Excluding RT-PCR–positive individuals, antibody positivity was associated with fever in adults and children (P = .02 and P = .002, respectively), abdominal pain in children (P = .001), and chest pain in adults (P = .02). Within antibody-positive individuals, 40% of students and 18% of staff reported no symptoms (P = .01).ConclusionsTeachers were more affected during the outbreak and younger children were at a higher risk for infection, likely because index case(s) were teachers and/or parents from the preschool. Self-administered antibody testing, supervised remotely, proved to be a suitable and rapid tool. Our study provides useful information for school reopenings.