bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Structure of Annealed Hafnium Bronze Subjected to Severe Plastic Deformation by High Pressure Torsion
Authors: Stolbovsky A , Popov V , Falahutdinov R 
Published: November 2020

Abstract
The structure and mechanical properties of low-alloyed hafnium bronze (Cu-0.78 wt. % Hf) under severe plastic deformation by high-pressure torsion (HPT) by 1, 3 and 5 revolutions of anvils at room temperature have been studied by electron microscopy and microhardness measurements. In the initial annealed state Hf is practically completely bonded in intermetallic compounds. The structure of bronze specimens deformed by HPT is stable and does not undergo any changes after unloading and long room temperature ageing. Under the deformation a dispersed submicrocrystalline structure gradient along specimen radius is formed. Average crystallite size in the radius middle is 200 nm after 1 revolution and 120 nm after 5 revolutions of anvils. It is demonstrated that in all the specimens studied including those deformed by 5 revolutions the structure is not uniform which is confirmed by microhardness measurements. Such behavior of hafnium bronze with Hf bonded in precipitates has much in common with the behavior of pure copper. However, the room temperature stability of the structures obtained by HPT demonstrates similar behavior with that of low-alloyed tin bronze.
Deformation Cone of Pilger Rolling for Forward and Reverse Motion
Authors: Koval G I , Karimova T G 
Published: November 2020

Abstract
Two mutually perpendicular pairs of rolls show the distinctive features of the existing pilger rolling processes from the pilger rolling process developed at SUSU. The peripheral velocity vectors of them are placed in different directions from the transition zone formation position from the initial billet to the finished profile (deformation cone). The change in the deformation cone shape with the billet free ends during the pilger rolling process by two mutually perpendicular pairs of rolls, circumferential velocity vectors placed in different directions, are considered. It is accepted that during forward rolling, the billet feed is equal to m, and during reverse rolling it is equal to mλ to ensure equality of displaceable feed volumes when describing the changes sequence in the deformation cone parameters. The gradual supply volumes flattening with a forward and reverse stroke to design values is shown. This was obtained by considering several cycles of pilger rolling by sequentially increasing the feed volumes during reverse rolling and reducing the feed volumes during forward rolling.
An Investigation of the Laser Welding Process for Dual-Phase Steel via Regression Analysis
Authors: Zhao Dawei , Ivanov Mikhail , Wang Yuanxun 
Published: November 2020

Abstract
Abstract In this work, a systematic investigation was undertaken to explore the effects of welding process parameters on the mechanical performances of the welding joints in the laser welding process for DP600. Welding experiments were arranged by a uniform experimental design method with four control factors (laser power, welding speed, focal point position, and side-blowing shield gas flow). The tensile strength of the welding joints was used to quantify the welding quality. A mathematical model based on stepwise regression analysis was employed to correlate the welding process parameters and the tensile strength. The effects of the welding process parameters on the welding quality were discussed. The genetic algorithm was then employed to select the optimum welding parameters. The verification test results proved that the method proposed in this paper could effectively evaluate and optimize the welding quality within the range of process parameters, which could enhance the welding performance in the laser welding process as feasibly and effectively as possible.
Dependence of Weld Penetration Shape on Energy Efficiency in Electron Beam Welding Process
Authors: Goncharov A L , Sliva A P , Kharitonov I A 
Published: November 2020

Abstract
Investigation of relation between parameters of weld penetration shape and energy efficiency of electron beam welding process was performed in the paper. Analysis of welds cross sections of 316 L(N) steel weld joints obtained by the electron beam welding in the wide range of welding regimes is carried out. It is shown that the dependences of the thermal efficiency on the penetration area at different welding speeds are linear. According to the results, the thermal efficiency coefficient may exceed the ultimate theoretical value for linear heat source. Beam sweep does not affect essentially on the rate of thermal efficiency coefficient, since sweep application leads to an insignificant change in the area of the boundary of the weld pool with the base metal, and therefore, the amount of energy removed through this boundary also changes insignificantly and the penetration area remains almost constant.
Effect of Temperature Field on Mechanical Properties of Direct Laser Deposited Ti-6Al-4V Alloy
Authors: Gushchina M O , Yu Ivanov S , Vildanov A M 
Published: November 2020

Abstract
The mechanical and service properties of Ti-6Al-4V alloy parts produced by direct laser deposition (DLD) depend on the thermal cycle parameters. The temperature field during deposition is significantly affected not only by the parameters of the process, but also by the interpass dwell time and length of the deposited layers. The aim of the article is to establish the relationship between mechanical properties of deposited Ti-6Al-4V samples and DLD thermal cycle parameters. Numerical simulation was used in order to establish relationship between temperature field parameter and the process parameters. The nonlinear three-dimensional heat conduction problem was solved by the finite element method. It is shown that an increase in the dwell time between passes from 5 to 10 seconds leads to a significant decrease in the inter-pass temperature and an increase in the cooling rate. This leads to the metastable structure formation of the deposited layers of Ti-6Al-4V that consists mainly of a nonequilibrium a’-phase which hardness is higher than 390 HV. Without dwell time an equilibrium a + (3 structure with hardness of 360 HV and higher elongation is formed.
Cold Spray Deposition of Copper/Tungsten Composite Coatings
Authors: Doubenskaia M , Latfulina Yu S , Samodurova M N 
Published: November 2020

AbstractThis work is devoted to the study of the microstructure and the properties of the Cu-W composite coatings deposited using cold spray technology. This process allows fabrication of high-quality coatings on large surfaces of different types of materials. The technology is widely used and investigated due to technological simplicity, wide range of sprayed materials and operating temperatures. However, there are some technological problems which appear when materials with low melting temperatures are sprayed. During softening, the particles adhere to the nozzle walls and block spraying. By the way, it is possible to solve the problem adding some ceramics particles to the spraying mixture of powders. As a result, the formed coating will have better mechanical properties and the technological problem will be solved. The analysis of the general results of the microstructure studies and experiments, and comparison with other coating methods are given. Moreover, the experimental procedure of samples preparation and used equipment are given. It is shown the microstructure before and after heat treatment of the samples sprayed, microhardness measurements, thermal conductivity measurements.
Improving the Performance Characteristics of the Drawing Machine Intermediate Block Working Surface by Additive Technologies
Authors: Radionova L V , Samodurova M N , Chaplygin B A 
Published: November 2020

Abstract
This paper presents the study results of the drawing machine intermediate block surface hardening treatment by the methods of additive technologies. Laser surfacing of powder material Fe-4,5Cr-4,5Mo-5,5 W-4V on the intermediate block working surface a wear-resistant layer with a hardness of 52-54 HRC with a thickness of more than 1.5 mm. The laser complex LaserClad 4 C R120 based on the industrial robotic manipulator KUKA KR-120 together with the positioner is able to melt powder material only on the working surface of the intermediate block, thereby significantly reducing its cost and labor intensity during its manufacture. The applying of detonation spraying with subsequent penetration for this type of product proved to be ineffective. The detonation coating itself with a powder material based on tungsten carbide turned out to be uniform and had a hardness in the range of 61 -65 HRC. But rather large pores and cracks appeared in it after penetration, which is associated with a significant difference in the coefficients of thermal linear expansion of steel 41Cr4 (14-10-6 1/K) and an alloy based on tungsten carbide (3,9-10-6 1/K).
The study of visible-light photocatalytic degradation activity of Ag doped g-C3N4 obtained by heating process
Authors: Liu Xiao , Tang Ru-Yi , Xia Xue-Min , Qin Yao-Yu , Zhang Xia 
Published: November 2020

Abstract
In this paper, Ag nanoparticles (Ag NPs) were loaded on pure g-C3N4 (CN) via two different methods of direct heating and indirect heating to form g-C3N4/Ag-DX and g-C3N4/Ag-IDX photocatalysts, respectively. Using methylene blue as the degradation dye, the photocatalytic performance of g-C3N4/Ag-DX and g-C3N4/Ag-IDX was studied through visible light photocatalysis experiments. The results demonstrated that the photocatalytic performance of g-C3N4/Ag-DX and g-C3N4/Ag-IDX both increases with the increase in content of Ag nanoparticles. It is obvious that g-C3N4/Ag-ID8 has the optimal photocatalytic activity. Meanwhile, the g-C3N4/Ag-ID8 has excellent stability and can be reused in photocatalysis experiments.
Fabrication and mechanical characterization of YAG ceramic-composite with alumina nanoparticles using slip casting and sintering process
Authors: Torki M , Movahedi B , Ghazanfari S , Milani M 
Published: November 2020

Abstract
The aim of this study was to fabricate a YAG/Al2O3 ceramic composite with different alumina nanoparticles using slip casting and the atmospheric sintering process. In addition, some mechanical properties such as hardness and elastic modules of this ceramic were evaluated using the nanoindention technique. The results showed that the rheological behavior of the slurry was optimized to the solid loading of 55 wt%; also, the relative density of the green body was enhanced up to 65%. Relative density was increased to 99.5% after sintering at 1700 °C for 12 h; further, the pore size (150 nm) was reduced to half of that of powder particles. It should be, however, noted that the optimum amount of alumina nanoparticles as a reinforcing agent in the matrix was less than 5%wt and the composite hardness was increased to 7.3%, as compared to the pure YAG ceramic.
Thermal behavior and combustion performance of Al/MoO3 nanothermites with addition of poly (vinylidene fluorine) using electrospraying
Authors: Chen Jialin , Guo Tao , Yao Miao , Song Jiaxing , Ding Wen , Mao Yiming , Li Shi , Zhu Rui 
Published: November 2020

Abstract
To investigate the effect of the addition of poly (vinylidene fluoride) (PVDF) on nanothermites, Al/MoO3/PVDF energetic nanocomposites were prepared using electrospraying method. As a control group, Al/MoO3 was also designed. Then, both samples were tested by FE-SEM, XRD and TG-DSC. TG-DSC results showed that the Al/MoO3/PVDF energetic nanocomposites released more than 934.0 J g−1 with two obvious exothermic peaks. Compared with the control group of 800.7 J g−1 heat, it changed the thermal performance to some extent. There were Mo2C among the residues products after the reaction via XRD. The activation energy (Ea) was analyzed using the Kissinger method under different heating rates by DSC. The addition of PVDF reduced the Ea of the thermites. To explore the combustion performance, a preliminary experiment was designed. The Al/MoO3/PVDF energetic nanocomposites were easier to ignite and the burning was more durable, which was significant in solid propulsion and applications requiring extended combustion time.
Optimization of the recursive least squares algorithm for capacitive strain sensing
Authors: Bohnker Jillian , Breuer Kenneth 
Published: November 2020

Abstract
The use of dielectric elastomers as integrated actuators and strain sensors offers a simple approach for closed-loop control in a wide range of applications. While a number of approaches for self-sensing have been proposed, the adaptive online algorithm offers an appealing combination of high accuracy and low computational cost. In this work, the recursive least squares algorithm will be applied to capacitive deformation sensing of dielectric elastomers. With the goal of minimizing sampling rate while achieving a set accuracy over a desired range of deformation frequencies, the probe frequency, sampling frequency, and forgetting factor will be optimized. It will be shown that the accuracy is primarily determined by a nondimensionalized variable,

W

¯

, which defines the proportion of a hypothetical deformation cycle that is weighted more heavily by the algorithm. Ultimately, this optimized algorithm will be validated by variably inflating a dielectric elastomer membrane and comparing the algorithm output to membrane deformation measured by video.
Clinical profile and predictors of in-hospital mortality among older patients hospitalised for COVID-19
Authors: Becerra-Muñoz Víctor Manuel , Núñez-Gil Iván J , Eid Charbel Maroun , García Aguado Marcos , Romero Rodolfo , Huang Jia , Mulet Alba , Ugo Fabrizio , Rametta Francesco , Liebetrau Christoph , Aparisi Alvaro , Fernández-Rozas Inmaculada , Viana-Llamas María C , Feltes Gisela , Pepe Martino , Moreno-Rondón Luis A , Cerrato Enrico , Raposeiras-Roubín Sergio , Alfonso Emilio , Carrero-Fernández Ana , Buzón-Martín Luis , Abumayyaleh Mohammad , Gonzalez Adelina , Fernández Ortiz Antonio , Macaya Carlos , Estrada Vicente , Fernández-Pérez Cristina , Gómez-Doblas Juan José 
Published: November 2020

Abstract

Background
the coronavirus disease 2019 (COVID-19) is characterized by poor outcomes and mortality, particularly in older patients.

Methods
post hoc analysis of the international, multicentre, ‘real-world’ HOPE COVID-19 registry. All patients aged ≥65 years hospitalised for COVID-19 were selected. Epidemiological, clinical, analytical and outcome data were obtained. A comparative study between two age subgroups, 65–74 and ≥75 years, was performed. The primary endpoint was all cause in-hospital mortality.

Results
about, 1,520 patients aged ≥65 years (60.3% male, median age of 76 [IQR 71–83] years) were included. Comorbidities such as hypertension (69.2%), dyslipidaemia (48.6%), cardiovascular diseases (any chronic heart disease in 38.4% and cerebrovascular disease in 12.5%), and chronic lung disease (25.3%) were prevalent, and 49.6% were on ACEI/ARBs. Patients aged 75 years and older suffered more in-hospital complications (respiratory failure, heart failure, renal failure, sepsis) and a significantly higher mortality (18.4 vs. 48.2%, P &lt; 0.001), but fewer admissions to intensive care units (11.2 vs. 4.8%). In the overall cohort, multivariable analysis demonstrated age ≥75 (OR 3.54), chronic kidney disease (OR 3.36), dementia (OR 8.06), peripheral oxygen saturation at admission &lt;92% (OR 5.85), severe lymphopenia (&lt;500/mm3) (OR 3.36) and qSOFA (Quick Sequential Organ Failure Assessment Score) &gt;1 (OR 8.31) to be independent predictors of mortality.

Conclusion
patients aged ≥65 years hospitalised for COVID-19 had high rates of in-hospital complications and mortality, especially among patients 75 years or older. Age ≥75 years, dementia, peripheral oxygen saturation &lt;92%, severe lymphopenia and qSOFA scale &gt;1 were independent predictors of mortality in this population.
Optimizing digitalization effort in morphometrics
Authors: Evin Allowen , Bonhomme Vincent , Claude Julien 
Published: November 2020

Abstract
Quantifying phenotypes is a common practice for addressing questions regarding morphological variation. The time dedicated to data acquisition can vary greatly depending on methods and on the required quantity of information. Optimizing digitization effort can be done either by pooling datasets among users, by automatizing data collection, or by reducing the number of measurements. Pooling datasets among users is not without risk since potential errors arising from multiple operators in data acquisition prevent combining morphometric datasets. We present an analytical workflow to estimate within and among operator biases and to assess whether morphometric datasets can be pooled. We show that pooling and sharing data requires careful examination of the errors occurring during data acquisition, that the choice of morphometric approach influences amount of error, and that in some cases pooling data should be avoided. The demonstration is based on a worked example (Sus scrofa teeth) using a combinations of 18 morphometric approaches and datasets for which we identified and quantified several potential sources of errors in the workflow. We show that it is possible to estimate the analytical power of a study using a small subset of data to select the best morphometric protocol and to optimize the number of variables necessary for analysis. In particular, we focus on semi-landmarks, which often produce an inflation of variables in contrast to the number of available observations use in statistical testing. We show how the workflow can be used for optimizing digitization efforts and provide recommendations for best practices in error management.
Factors Associated with Attitudes and Knowledge of First-Semester College Students toward Climate Change
Authors: Harrod Sara E , Rolland Virginie 
Published: November 2020

AbstractDespite scientific consensus and educational efforts, approximately 25% of Americans remain unconvinced of anthropogenic climate change (ACC), and significant misconceptions remain. Many studies have assessed adults’ views, but it is important to also understand the perceptions of younger individuals who will deal with the future impacts of ACC. In this study, we aimed to determine first-semester college students’ attitudes toward and knowledge of ACC, which factors are associated with these measures, and whether knowledge scores differ among audience segments. We issued surveys at 19 American universities and received 2355 responses. The surveys contained sections assessing attitudes, knowledge, and demographics. We analyzed the attitudes and knowledge in ordinal and beta regressions. Most (73.6%) of the students were very concerned about ACC, and their average knowledge scores were high (0.89, standard error = 0.003). Attitude and knowledge were associated with a combination of personal and environmental factors. The concerned students had higher scores, suggesting education may be an important mitigation tool.
The contradictory role of androgens in cutaneous and major burn wound healing
Authors: Shi Huaikai , Cheer Kenny , Simanainen Ulla , Lesmana Brian , Ma Duncan , Hew Jonathan J , Parungao Roxanne J , Li Zhe , Cooper Mark S , Handelsman David J , Maitz Peter K , Wang Yiwei 
Published: November 2020

Abstract
Wound healing is a complex process involving four overlapping phases: haemostasis, inflammation, cell recruitment and matrix remodeling. In mouse models, surgical, pharmacological and genetic approaches targeting androgen actions in skin have shown that androgens increase interleukin-6 and tumor necrosis factor-α production and reduce wound re-epithelization and matrix deposition, retarding cutaneous wound healing. Similarly, clinical studies have shown that cutaneous wound healing is slower in men compared to women. However, in major burn injury, which triggers not only local wound-healing processes but also systemic hypermetabolism, the role of androgens is poorly understood. Recent studies have claimed that a synthetic androgen, oxandrolone, increases protein synthesis, improves lean body mass and shortens length of hospital stay. However, the possible mechanisms by which oxandrolone regulates major burn injury have not been reported. In this review, we summarize the current findings on the roles of androgens in cutaneous and major burn wound healing, as well as androgens as a potential therapeutic treatment option for patients with major burn injuries.
A Connectomic Hypothesis for the Hominization of the Brain
Authors: Changeux Jean-Pierre , Goulas Alexandros , Hilgetag Claus C 
Published: November 2020

AbstractCognitive abilities of the human brain, including language, have expanded dramatically in the course of our recent evolution from nonhuman primates, despite only minor apparent changes at the gene level. The hypothesis we propose for this paradox relies upon fundamental features of human brain connectivity, which contribute to a characteristic anatomical, functional, and computational neural phenotype, offering a parsimonious framework for connectomic changes taking place upon the human-specific evolution of the genome. Many human connectomic features might be accounted for by substantially increased brain size within the global neural architecture of the primate brain, resulting in a larger number of neurons and areas and the sparsification, increased modularity, and laminar differentiation of cortical connections. The combination of these features with the developmental expansion of upper cortical layers, prolonged postnatal brain development, and multiplied nongenetic interactions with the physical, social, and cultural environment gives rise to categorically human-specific cognitive abilities including the recursivity of language. Thus, a small set of genetic regulatory events affecting quantitative gene expression may plausibly account for the origins of human brain connectivity and cognition.
Should Therapeutic Drug Monitoring Based on the Vancomycin Area Under the Concentration-Time Curve Be Standard for Serious Methicillin-Resistant Staphylococcus aureus Infections?—No
Authors: Jorgensen Sarah C J , Spellberg Brad , Shorr Andrew F , Wright William F 
Published: November 2020

Abstract
In this counterpoint we critically appraise the evidence supporting therapeutic drug monitoring based on the vancomycin 24-hour area under the concentration-time curve (AUC24) for serious methicillin-resistant Staphylococcus aureus infections. We reveal methodologically weaknesses and inconsistencies in the data and suggest that, in the absence of clear and convincing evidence of benefit compared with modestly reducing trough targets, alternative strategies are more likely to result in superior safety and efficacy. These include focusing on fundamental antibiotic stewardship to limit vancomycin exposure overall, achieving earlier and more complete source control, and establishing alternative therapeutic options to vancomycin. Implementation of AUC24-based therapeutic drug monitoring will take resources away from these more promising, alternative solutions.
Bayesian inference of network structure from unreliable data
Authors: Young Jean-Gabriel , Cantwell George T , Newman M E J 
Published: November 2020

Abstract
Most empirical studies of complex networks do not return direct, error-free measurements of network structure. Instead, they typically rely on indirect measurements that are often error prone and unreliable. A fundamental problem in empirical network science is how to make the best possible estimates of network structure given such unreliable data. In this article, we describe a fully Bayesian method for reconstructing networks from observational data in any format, even when the data contain substantial measurement error and when the nature and magnitude of that error is unknown. The method is introduced through pedagogical case studies using real-world example networks, and specifically tailored to allow straightforward, computationally efficient implementation with a minimum of technical input. Computer code implementing the method is publicly available.