bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increasing the Service Lifetime of a Working Elements of Mixer-Pneumosuperchargers for the Building Mixtures Preparation
Authors: Gabelchenko N I , Belov A A , Gabelchenko A I 
Published: November 2020

Abstract
Comparative studies of the blade’s materials for mixer-pneumosuperchargers operated under abrasive conditions were carried out. For this purpose in the production environment at the construction site the service lifetime of the blades offered by various manufacturers was measured on four “SO – 241” mixer-pneumosuperchargers. Production of building mixture in quantity declared by the manufacturer was used as a control period. It is shown that blades made of 110G13L steel retained their service properties almost until the completion of the control period. Also, the composition and technology for producing the working elements of mixer-pneumosuperchargers from wear-resistant white cast iron alloyed with chromium and manganese was developed. The test results showed that the blades made of the proposed material exceeded the service lifetime of the blades made of 110G13L steel.
On the Issue of Heat Balance of Molds for Injection Molding of Non-Ferrous Metal Alloys
Authors: Gavariev R V , Gavarieva K N 
Published: November 2020

Abstract
The article presents a study of the thermal balance of injection molding molds. The main components of the balance equation are indicated, as well as the factors that affect them. It is revealed that the most important factor affecting the thermal balance is the material of the mold. The use of coatings applied by the method of physical vapor deposition on the forming surfaces of molds is proposed. These coatings provide a reduction in friction between the forming surface and the poured melt at the time of filling, which reduces the temperature of the forming surface by 10-12°C. Among the considered options, the most optimal indicators were for titanium and molybdenum metal nitride (Ti, Mo) N.
Investigation of Lateral Surface Contour at Forging of Billets with Upsetting Ratio Above 2.5
Authors: Anishchenko O , Kukhar V , Klimov E 
Published: November 2020

Abstract
List of the most used functions (circle, parabola, ellipse, hyperbola, cosine, hyperbolic cosine), which are applied to approximate of billets contours at upsetting and pointed to the lack of a universal equation for these purposes, was analyzed. The advantages and disadvantages of each type of equations are pointed. The paper presents the results of upsetting of lead cylindrical specimens with a upsetting ratio 2.0-4.0. The experiment shows the stages of a “double barrel” forming on the lateral surface of a billet and its subsequent transition to a single one. The authors propose to use the “superformula” recently invented by Johan Gielis as a universal equation that allows to approximate the contour of the lateral surface of a billet at all stages of upsetting. The paper presents comparative initial data necessaries to determine upsetting force and pressure, taking into account the barrel-shape calculated by the superformula, and the coefficient of friction determined by Gubkin’s method. The equations coefficients have find, which give approximately the same results comparables to upsetting of specimens from lead, and these equations proposed for the calculation of the forming at upsetting from double-barrel to single-barrel workpiece.
Research of the Influence of the Rarefaction Degree on the Metal Protection Quality and Geometric Welding Parameters During Arc Welding in the Controlled Atmosphere
Authors: Sitnikov I V , Trushnikov D N , Permyakov G L 
Published: November 2020

Abstract
This article is devoted to the urgent issue of welding metals and alloys that are widely used in modern aerospace industry. The paper describes the effect of the degree of rarefaction of the controlled atmosphere on the quality of protection of the weld metal and the weld zone, as well as on the change in the geometric parameters of the weld during arc welding in a controlled atmosphere. The main advantages of arc welding in a controlled atmosphere of refractory, heat-resistant, heat-resistant, corrosion-resistant metals and their alloys are indicated. The welding modes used and the welds obtained with these modes are presented. The influence of the degree of rarefaction on the change in the quality of protection of the weld metal and the heat-affected zone is described. The degree of rarefaction of the controlled atmosphere ranged from 200 to 1000 mbar. Dependencies are obtained that describe the effect of the degree of rarefaction on the geometric parameters of welds.
Effect of Welding Speed on Electron Beam Welding Thermal Efficiency
Authors: Terentyev E V , Sliva A P , Santalova Yu V 
Published: November 2020

Abstract
The results of thermal efficiency evaluation during electron beam welding of alloys with different thermophysical properties in the range of welding speeds from 20 m/h to 120 m/h are presented. It was shown that the thermal efficiency increased in accordance with the rising welding speed. Also, the thermal efficiency greatly depends on the thermal conductivity: the lower the thermal conductivity, the higher the thermal efficiency. Thus, with an increase in welding speed from 20 m/h to 120 m/h, the thermal efficiency grew steadily for all three considered types of alloys: values for a titanium alloy 5 V went up from 54% to 67%, while for the steel 40Kh13 values rose from 46% to 63% and the most significant increment related to duralumin D16, the thermal efficiency for this alloy increased from 18% to 40%. The equation which established the ratio between the thermal efficiency, welding speed and thermal conductivity for electron beam welding with full penetration was derived.
A Method of Managing Technological Heredity in the Additive Growing of Objects from Cold-Resistant Materials on a Machine with Technology for Electric Arc Welding
Authors: Shatagin D , Kabaldin Y , Kolchin P 
Published: November 2020

Abstract
The article considers the issue of managing print parameters to minimize the impact of technological heredity on the layers of the formed object. An analysis of the stability of the 3D printing process was carried out using acoustic emission data. The fractal dimensions of the acoustic emission attractor for a stable and unstable 3D printing process have been obtained. A method for controlling process stability by tracking 3D printing modes and assessing their stability using an artificial neural network is proposed. The mechanical properties of printed samples were evaluated under normal conditions and at low temperatures in the Arctic and the far north.
Changes in the Structure and Properties of Nickel-Zinc Spinel Nanoferrites Series for 3D-Printing
Authors: Shamray I I , Yu Buz’ko V , Goryachko A I 
Published: November 2020

Abstract
The family of nickel-zinc nanoferrites with general formula NixZn1 – xFe2O4 for 3D printing were synthesized via pyrochemical urea-nitrate method and annealed at temperatures of up to 770 K. The ferrite powder microstructure was studied by SEM and XRD methods. Average nanocrystallite sizes of 21 to 32 nm and average nanoparticles sizes of 22 to 50 nm were determined. The DC electrical conductivity of NixZn1 – xFe2O4 clearly shows the change in conduction behavior of samples with increase in nickel content. The observed low electrical conductivity with values at 0.l-0.3 and 0.8-0.9 parts of nickel ion for NixZn1 – xFe2O4 is due to change in cation distribution in spinel structure. The microwave absorbing properties of ferrites at 9.15 GHz were analyzed by FMR and maximum microwave absorption is that of compositions NixZn1 – xFe2O4 with x = 0.15 – 0.30. Additive manufacturing FDM 3D-printing process with PLA-nanoferrite filament for fabricating magnetic components also was demonstrated.
Development of a Mathematical Model of an Arc Plasma Discharge in Vacuum, Describing the Joint Solution of the Navier-Stokes Equations, Heat Transfer, with Equations of Plasma Theory
Authors: Sitnikov I V , Trushnikov D N , Permyakov G L 
Published: November 2020

AbstractThis article is devoted to the description of arc processes in a vacuum, relevant today for the melting of wire materials in the implementation of hybrid technologies of layer-by-layer synthesis. The directions of using an electric arc as a source of heat in creating arc additive technologies are indicated. One of the most promising methods for creating an arc discharge in vacuum using a non-consumable thermoelectronic hollow cathode is presented. A two-dimensional model has been developed for studying a hollow-cathode arc discharge in vacuum, where argon was used as the plasma-forming gas. All calculations were carried out in an axisymmetric formulation. To obtain a numerical solution, the COMSOL Multiphysics application software package was used. The obtained simulation results showed a satisfactory agreement with the literature and experimental data.
Current challenges for unseen-epitope TCR interaction prediction and a new perspective derived from image classification
Authors: Moris Pieter , De Pauw Joey , Postovskaya Anna , Gielis Sofie , De Neuter Nicolas , Bittremieux Wout , Ogunjimi Benson , Laukens Kris , Meysman Pieter 
Published: November 2020

Abstract
The prediction of epitope recognition by T-cell receptors (TCRs) has seen many advancements in recent years, with several methods now available that can predict recognition for a specific set of epitopes. However, the generic case of evaluating all possible TCR-epitope pairs remains challenging, mainly due to the high diversity of the interacting sequences and the limited amount of currently available training data. In this work, we provide an overview of the current state of this unsolved problem. First, we examine appropriate validation strategies to accurately assess the generalization performance of generic TCR-epitope recognition models when applied to both seen and unseen epitopes. In addition, we present a novel feature representation approach, which we call ImRex (interaction map recognition). This approach is based on the pairwise combination of physicochemical properties of the individual amino acids in the CDR3 and epitope sequences, which provides a convolutional neural network with the combined representation of both sequences. Lastly, we highlight various challenges that are specific to TCR-epitope data and that can adversely affect model performance. These include the issue of selecting negative data, the imbalanced epitope distribution of curated TCR-epitope datasets and the potential exchangeability of TCR alpha and beta chains. Our results indicate that while extrapolation to unseen epitopes remains a difficult challenge, ImRex makes this feasible for a subset of epitopes that are not too dissimilar from the training data. We show that appropriate feature engineering methods and rigorous benchmark standards are required to create and validate TCR-epitope predictive models.
DNA Methyltransferase 3A Is Involved in the Sustained Effects of Chronic Stress on Synaptic Functions and Behaviors
Authors: Wei Jing , Cheng Jia , Waddell Nicholas J , Wang Zi-Jun , Pang Xiaodong , Cao Qing , Liu Aiyi , Chitaman Javed M , Abreu Kristen , Jasrotia Rahul Singh , Duffney Lara J , Zhang Jinfeng , Dietz David M , Feng Jian , Yan Zhen 
Published: November 2020

Abstract
Emerging evidence suggests that epigenetic mechanisms regulate aberrant gene transcription in stress-associated mental disorders. However, it remains to be elucidated about the role of DNA methylation and its catalyzing enzymes, DNA methyltransferases (DNMTs), in this process. Here, we found that male rats exposed to chronic (2-week) unpredictable stress exhibited a substantial reduction of Dnmt3a after stress cessation in the prefrontal cortex (PFC), a key target region of stress. Treatment of unstressed control rats with DNMT inhibitors recapitulated the effect of chronic unpredictable stress on decreased AMPAR expression and function in PFC. In contrast, overexpression of Dnmt3a in PFC of stressed animals prevented the loss of glutamatergic responses. Moreover, the stress-induced behavioral abnormalities, including the impaired recognition memory, heightened aggression, and hyperlocomotion, were partially attenuated by Dnmt3a expression in PFC of stressed animals. Finally, we found that there were genome-wide DNA methylation changes and transcriptome alterations in PFC of stressed rats, both of which were enriched at several neural pathways, including glutamatergic synapse and microtubule-associated protein kinase signaling. These results have therefore recognized the potential role of DNA epigenetic modification in stress-induced disturbance of synaptic functions and cognitive and emotional processes.
Cost-effectiveness of a Novel Lipoarabinomannan Test for Tuberculosis in Patients With Human Immunodeficiency Virus
Authors: Reddy Krishna P , Denkinger Claudia M , Broger Tobias , McCann Nicole C , Gupta-Wright Ankur , Kerkhoff Andrew D , Pei Pamela P , Shebl Fatma M , Fielding Katherine L , Nicol Mark P , Horsburgh C Robert , Meintjes Graeme , Freedberg Kenneth A , Wood Robin , Walensky Rochelle P 
Published: November 2020

AbstractBackgroundA novel urine lipoarabinomannan assay (FujiLAM) has higher sensitivity and higher cost than the first-generation AlereLAM assay. We evaluated the cost-effectiveness of FujiLAM for tuberculosis testing among hospitalized people with human immunodeficiency virus (HIV), irrespective of symptoms.MethodsWe used a microsimulation model to project clinical and economic outcomes of 3 testing strategies: (1) sputum Xpert MTB/RIF (Xpert), (2) sputum Xpert plus urine AlereLAM (Xpert+AlereLAM), (3) sputum Xpert plus urine FujiLAM (Xpert+FujiLAM). The modeled cohort matched that of a 2-country clinical trial. We applied diagnostic yields from a retrospective study (yields for Xpert/Xpert+AlereLAM/Xpert+FujiLAM among those with CD4 &lt;200 cells/µL: 33%/62%/70%; among those with CD4 ≥200 cells/µL: 33%/35%/47%). Costs of Xpert/AlereLAM/FujiLAM were US$15/3/6 (South Africa) and $25/3/6 (Malawi). Xpert+FujiLAM was considered cost-effective if its incremental cost-effectiveness ratio (US$/year-of-life saved) was &lt;$940 (South Africa) and &lt;$750 (Malawi). We varied key parameters in sensitivity analysis and performed a budget impact analysis of implementing FujiLAM countrywide.ResultsCompared with Xpert+AlereLAM, Xpert+FujiLAM increased life expectancy by 0.2 years for those tested in South Africa and Malawi. Xpert+FujiLAM was cost-effective in both countries. Xpert+FujiLAM for all patients remained cost-effective compared with sequential testing and CD4-stratified testing strategies. FujiLAM use added 3.5% (South Africa) and 4.7% (Malawi) to 5-year healthcare costs of tested patients, primarily reflecting ongoing HIV treatment costs among survivors.ConclusionsFujiLAM with Xpert for tuberculosis testing in hospitalized people with HIV is likely to increase life expectancy and be cost-effective at the currently anticipated price in South Africa and Malawi. Additional studies should evaluate FujiLAM in clinical practice settings.
Letermovir and Maribavir for the Treatment and Prevention of Cytomegalovirus Infection in Solid Organ and Stem Cell Transplant Recipients
Authors: Imlay Hannah N , Kaul Daniel R 
Published: November 2020

Abstract
Until recently, available drugs for cytomegalovirus (CMV) prevention and treatment in transplant patients included (val)ganciclovir, foscarnet, and cidofovir. Use of these drugs is limited by toxicity and the development of resistance. The 2017 approval of letermovir for prevention of CMV after stem cell transplant marked the first approval of an anti-CMV agent since 2003. The role of letermovir in treatment of established CMV infection or disease remains largely unstudied, although early reports suggest that a low barrier to resistance will likely limit efficacy as primary therapy for patients with refractory or resistant disease. The investigational agent maribavir has shown promise as preemptive treatment; in patients with refractory or resistant disease the emergence of resistance while on treatment has been observed and ongoing studies will define efficacy in this population. Both agents have unique mechanisms of action limiting cross resistance, and neither exhibit myelotoxicity or nephrotoxicity.
Comparative Effectiveness of Influenza Vaccines Among US Medicare Beneficiaries Ages 65 Years and Older During the 2019–2020 Season
Authors: Izurieta Hector S , Lu Michael , Kelman Jeffrey , Lu Yun , Lindaas Arnstein , Loc Julie , Pratt Douglas , Wei Yuqin , Chillarige Yoganand , Wernecke Michael , MaCurdy Thomas E , Forshee Richard 
Published: November 2020

Abstract

Background
Approximately 50 000 influenza-associated deaths occur annually in the United States, overwhelmingly among individuals aged ≥65 years. Although vaccination is the primary prevention tool, investigations have shown low vaccine effectiveness (VE) in recent years, particularly among the elderly. We analyzed the relative VE (RVE) of all influenza vaccines among Medicare beneficiaries aged ≥65 years to prevent influenza hospital encounters during the 2019–2020 season.

Methods
Retrospective cohort study using Poisson regression and inverse probability of treatment weighting (IPTW). Exposures included egg-based high-dose trivalent (HD-IIV3), egg-based adjuvanted trivalent (aIIV3), egg-based standard dose (SD) quadrivalent (IIV4), cell-based SD quadrivalent (cIIV4), and recombinant quadrivalent (RIV4) influenza vaccines.

Results
We studied 12.7 million vaccinated beneficiaries. Following IPTW, cohorts were well balanced for all covariates and health-seeking behavior indicators. In the adjusted analysis, RIV4 (RVE, 13.3%; 95% CI, 7.4–18.9%), aIIV3 (RVE, 8.2%; 95% CI, 4.2–12.0%), and HD-IIV3 (RVE, 6.8%; 95% CI, 3.3–10.1%) were significantly more effective in preventing hospital encounters than the reference egg-based SD IIV4, while cIIV4 was not significantly more effective than IIV4 (RVE, 2.8%; 95% CI, −2.8%, 8.2%). Our results were consistent across all analyses.

Conclusions
In this influenza B-Victoria and A(H1N1)–dominated season, RIV4 was moderately more effective than other vaccines, while HD-IIV3 and aIIV3 were more effective than the IIV4 vaccines, highlighting the contributions of antigen amount and adjuvant use to VE. Egg adaptation likely did not substantially affect our RVE evaluation. Our findings, specific to the 2019–2020 season, should be evaluated in other studies using virological case confirmation.
Impact of Age on Outcome of Rifapentine-Based Weekly Therapy for Latent Tuberculosis Infection
Authors: Huang Hung-Ling , Lee Meng-Rui , Cheng Meng-Hsuan , Lu Po-Liang , Huang Chun-Kai , Sheu Chau-Chyun , Lai Ping-Chang , Chen Tun-Chieh , Wang Jann-Yuan , Chong Inn-Wen 
Published: November 2020

Abstract

Background
Weekly rifapentine and isoniazid (3HP) is gaining popularity for latent tuberculosis infection treatment because of its short course and high completion rate. Prior to widespread use, comprehensive 3HP treatment assessment covering an all-age population is essential.

Methods
Participants receiving ≥1 3HP dose from September 2014 to December 2019 were stratified into elderly (≥65 years), middle-aged (&gt;35 & &lt;65 years), and younger (≤35 years) age groups. This study investigated the impact of age on treatment outcome, particularly systemic drug reactions (SDRs) and 3HP discontinuation.

Results
Overall, 134 of 579 (23.1%) participants were elderly. The completion rate was 83.1% overall and was highest and lowest in the younger group (94.5%) and elderly (73.9%) group, respectively. However, the 3HP discontinuation rate was not significantly different among the 3 groups in multivariate logistic regression analysis. In total, 362 (62.5%) participants experienced 1 or more adverse drug reactions (ADRs), of which 38 (10.5%) and 98 (27.1%) required temporary and permanent treatment interruption, respectively. The SDR risk was 11.2% in overall and 17.1% in the middle-aged group, 3.04-fold higher than that in the elderly group (P = .025). This finding was consistently observed in different clinical settings. Hypertensive events accompanied with flu-like symptoms occurred in 11.2% of elderly participants, and accounted for 50% of grade ≥3 ADRs.

Conclusions
With proper medical support and programmatic follow-up, the 3HP completion rate is &gt;70% even in elderly participants. In middle-aged and elderly individuals, 3HP should be employed with caution because of risk of SDRs and hypertensive events, respectively.
Summary: Under programmatic medical support, widespread use of weekly rifapentine and isoniazid (3HP) for latent tuberculosis treatment is possible for its high completion rate. 3HP should be employed with caution for risk of systemic drug reactions and hypertensive events in middle-aged and elderly individuals, respectively.
Biomarkers for Risk Assessment in Atrial Fibrillation
Authors: Berg David D , Ruff Christian T , Morrow David A 
Published: November 2020

Abstract

Background
Atrial fibrillation (AF) is associated with an increased risk of thromboembolism, which can be significantly reduced with anticoagulant treatment. Key goals in the clinical management of AF are the identification of patients at high risk for developing AF and accurate stratification of the risk of stroke and systemic embolic events (S/SEE) as well as treatment-related major bleeding.

Content
In this review, we describe the expanding evidence regarding the use of circulating biomarkers for predicting the risks of both incident AF and its clinically important complications of S/SEE and treatment-related major bleeding. We also review emerging biomarker-based scores for assessing these risks.

Summary
Patients with AF undergo progressive cardiac structural remodeling, which may precede the onset of the arrhythmia. Abnormal concentrations of circulating biomarkers reflecting the underlying pathophysiologic mechanisms of hemodynamic stress (i.e., natriuretic peptides), inflammation (i.e., C-reactive protein), and myocardial fibrosis identify patients at higher risk of developing AF. Circulating biomarkers can also be used to identify patients with AF who are at greatest risk for developing S/SEE or major bleeding. In particular, biomarkers of hemodynamic stress, myocardial injury (i.e., cardiac troponin), and coagulation activity (i.e., D-dimer) are key indicators of thromboembolic risk, and cardiac troponin and growth-differentiation factor-15 are strongly associated with risk of anticoagulant-related major bleeding. The biomarker-based age, biomarker, clinical history (ABC)-stroke and ABC-bleeding risk scores improve risk stratification for S/SEE and major bleeding, respectively, when compared with traditional clinical risk scores like the CHA2DS2-VASc and HAS-BLED scores.
School choice during a period of radical school reform. Evidence from academy conversion in England
Authors: Bertoni Marco , Gibbons Stephen , Silva Olmo 
Published: November 2020

SUMMARY
We study how demand responds to the rebranding of existing state schools as autonomous ‘academies’ in the context of a radical and large-scale reform to the English education system. The academy programme encouraged schools to opt out of local state control and funding, but provided parents and students with limited information on the expected benefits. We use administrative data on school applications for three cohorts of students to estimate whether this rebranding changes schools’ relative popularity. We find that families – particularly higher income, White British – are more likely to rank converted schools above non-converted schools on their applications. We also find that it is mainly schools that are high-performing, popular and proximate to families’ homes that attract extra demand after conversion. Overall, the patterns we document suggest that families read academy conversion as a signal of future quality gains – although this signal is in part misleading as we find limited evidence that conversion causes improved performance.