bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physico-mathematical model for bellows expansion joint efficiency by different manufacturing technologies
Authors: Novikov I A , Amirkhanov E I , Logunov V V 
Published: July 2019

Abstract
Increasing the reliability and improving of the technical characteristics of bellows and bellows expansion joints widely used in various fields of technology is a recent issue today. To solve this issue, a physico-mathematical model of functioning and measuring the reliability performance of bellows expansion joints is developed. The model includes two mechanisms of fatigue breakdown and wear: the Rehbinder effect and fretting. The developed model allows for calculating cyclic operation life for different bellows expansion joints. The model describes bellows expansion joints by three parameters: growth rate of a microcrack due to the Rehbinder effect, speed of fretting wear, and value of reversible period of microcracks formation. One can experimentally measure these parameters for different constructions and technologies of manufacturing of bellows expansion joints. Today, there are various technologies of bellows expansion joints manufacturing, including promising technologies of modification using fluoro-organic surfactants. The developed model is applied for assessment of different manufacturing technologies. Based on the analysis of the physico-mathematical model, the requirements for technologies are defined that lead to increasing of reliability of bellows expansion joints. The technologies of modification using fluoro-organic surfactants are theoretically proved to lead to increasing of the reliability performance of bellows expansion joints.
Diagnostics of an asynchronous motor powered from a self-commutated voltage inverter
Authors: Zhukovskiy Y L , Korolev N A , Koteleva N I 
Published: July 2019

Abstract
The presented research is focused on two issues. The first one is finding additional parameters that characterize the technical condition of an electric machine according to the current consumption. The second one is increasing of the informativeness of diagnostic methods in conditions of limited access to equipment and incomplete information. The paper discusses a method for diagnosing low and medium power asynchronous electric motors by electrical parameters. It is shown that asynchronous electric motors powered from a self-commutated voltage inverter have contained higher harmonic components in addition to the main harmonic. The non-sinusoidal voltage leads to the emerging of the highest current components in the stator winding of the motor. This is the reason for occurring of a pulsating component of the torque on the motor shaft. Therefore, there are two types of ripple: the one caused by the power supply from the self-commutated inverter and the one caused by defects. The moments’ coincidence of these ripples leads to increasing in the amplitude of oscillations. However, significant noise due to the presence of an autonomous inverter does not allow using the current spectrum to diagnose damage. Analysis of the hodographs of the Park’s vector of the stator current and voltage allows one to exclude harmonic components that were formed by the carrier frequency (and multiple of it). At the same time, analyzing the modulus of the Park’s vector and its spectrum, one can note pulsations of the amplitude values of the vector modulus corresponding to certain damage.
Prospects for the use of supercapacitors in railroad electric transport
Authors: Kuznetsov S M , Artemenko I V 
Published: July 2019

Abstract
In this article we considered a conversion device that ensures matching of the characteristics of the superconducting inductive (SPIN) energy sources and receivers of electric energy of the traditional performance in a power unit of autonomous perspective of the locomotive. Diesel-electric traction is a well-known and established technology for railways operators, but this alternative is non-ecological for the future because only electric traction has a considerable superiority. Besides, diesel-electric engines waste energy when resistive braking is used. This non-regenerative braking decreases the overall efficiency by 10-20%. With these premises, it is important to develop new strategies to increase the energy efficiency of diesel-electric haulage. To reach a better efficiency, a locomotive with energy storage (battery, super-capacitors) is theoretically proposed. Besides, the possibility of using a lower thermal engine with energy storage devices is considered too. This solution reduces diesel consumption and CO2 emissions while being economically viable. It supposes an efficient energy management because the diesel-electric locomotive could act as a dispersed mobile generation (DMG) unit when working under electric overhead lines, and it can be used as a distributed resource for this specific electric power system.
Magnetic lubricating oils based on organosilicon nanofluids
Authors: Bolotov A N , Novikov V V , Novikova O O 
Published: July 2019

Abstract
The results of studying tribotechnical and physicochemical properties of various liquids have proved applicability of a dispersion medium, which is based on organosilicon liquids, for producing new-generation magnetic lubricating oils. The paper gives recommendations for choosing a dispersed magnetic phase. There is an original approach to selecting surfactants for stabilization of a magnetic oil colloidal structure, taking into account their dielectric properties and the effect on friction. The paper describes technological features of the synthesis of lubricating oils based on polyethylsiloxane PES-5 and chlorphenylsiloxane KhS-2-1VV containing nanosized magnetite. It also investigates lubricating properties of magnetic oils based on oligodiethylsiloxane and oligomethyl(chlorophenyl)siloxane under various friction conditions and shows their specific features. It analyzes the influence of various additives and fillers on tribotechnical characteristics of magnetic oils. It also defines a different mechanism of additives effects on frictional contact properties. The results of magnetic oil tests determine the most promising compositions for practical use in tribounits. Finally, there are recommendations on practical application of optimal compositions of magnetic lubricating oils in traditional and perspective tribounits with various operational parameters.
Investigation of the microstructure of laser-deposited layers on cast-iron parts
Authors: Ivanov A , Kolmakova T 
Published: July 2019

Abstract
The gas-powder laser surfacing process of the cast-iron parts’ surfaces with the aim of increasing the wear resistance is investigated. Obtaining a coating with specified parameters (chemical composition, dimensions and quality of the rollers being deposited) depends on the irradiation regimes: power, processing speed, dimensions of the focal spot, powder consumption and the method of its delivery. St3 steel was used as a base material. Self-fluxing powders PG-C3R2, PG-PBH-6-2 and PG-US25-20Fe and their mixtures were used as a material for surfacing. The powders had a particle size of 50-160 microns. During laser heating, the structure is refined: the size of graphite plates is reduced from 150–200 µm to 20–40 µm in the melted zone, then their depth increases to the initial value. In the melted zone, graphite partially dissolves, partially burns out, forming pores. In the areas with the most complete dissolution of graphite plates, an austenite-martensitic structure with a hardness of up to 8.0–9.5 GPa is formed. In areas with a lower degree of dissolution of graphite, a martensite-sorbitol structure is formed with a hardness of 6.5–7.0 GPa. In the area of laser exposure, the hardness of the cast-iron welded parts increases by 3-4 times, which provides a significant increase in wear resistance.
The use of nanomaterials to improve the wear resistance of machine parts under fretting corrosion conditions
Authors: Krasnyy V A 
Published: July 2019

Abstract
The use of nanomaterials in different branches of machinery manufacturing has been studied. Nanomaterials application for improving working properties of machine parts has been described. Fullerene С60 friction properties have been studied; the works of some authors on improving metal resistance with fullerene С60 coating have been analyzed. It has been determined that there is little information about fullerene tribological properties and they are mostly about fullerene С60 as a thin film and additive to lubricating materials in sliding friction with minor normal loads. The test results on fullerene С60 impact as low-friction coating and additive to lubricating oil for reducing steel and brass samples wear in fretting corrosion are given.
Prospects for the use of martensites in the manufacture of adaptive anti-slipping spikes
Authors: Voiku I P , Sergeeva T V , Strikunov A V 
Published: July 2019

Abstract
The article substantiates the relevance of the development of an innovative device, namely an adaptive anti-slipping spike, and the prospects for the use of martensites in its manufacture. The device belongs to the automotive industry, specifically to the anti-slipping spikes. Tire treads of vehicles are equipped with these spikes to increase their adhesion to the roadway. The use of traditional anti-slipping spikes does not allow solving two problems at the same time: to ensure maximum adhesion of the vehicle’s wheel to the road surface and to minimize the destructive effect of anti-slipping spikes on the road surface. These tasks are solved by the fact that the proposed device is made according to the shape and size of traditional anti-slipping spikes but contains a retractable pin. The pin can be operated either by the substances with a negative coefficient of thermal expansion or martensitic materials. The article describes the prospects and features of their use.
Structure of digital and smart factories of the Industry 4.0
Authors: Zakoldaev D A , Shukalov A V , Zharinov I O , Zharinov O O 
Published: July 2019

Abstract
The current task of creating digital factories of the Industry 4.0 through the example of digital factories and smart factories engaged in the item designing is considered. The scheme of competences for the Industry 4.0 company is presented, based on the experience and the performance of the existing companies of the Industry 3.0. The digital factory scheme with project components and its informative support is presented. The smart factory scheme with production components is also given. Based on the results of the analysis of the digital design and manufacturing processes, the set of unique components providing information support to the project and production activity of enterprises is proposed. Implementing general components in the form of ready-to-use services deployed in the community cloud is proposed. Unification of the cloud services components is efficient for the Industry 4.0 companies which are parts of one virtual factory.
Informant-based hearing difficulties and the risk for mild cognitive impairment and dementia
Authors: Vassilaki Maria , Aakre Jeremiah A , Knopman David S , Kremers Walter K , Mielke Michelle M , Geda Yonas E , Machulda Mary M , Al Fakir Razan , Undavalli Chaitanya , Roberts Rosebud O , Petersen Ronald C 
Published: July 2019

AbstractBackground: hearing loss has been associated with mild cognitive impairment (MCI) and dementia. Studies have not assessed whether hearing difficulties (HD) that interfere with daily activities as reported by partners can be a marker for increased risk for cognitive decline and impairment.Objective: to assess the cross-sectional and longitudinal associations between informant-based HD, which interfere with daily activities and the risk for MCI and dementia.Methods: the study included 4812 participants without dementia, enrolled in the Mayo Clinic Study of Aging (mean age (SD) 73.7 (9.6) years) with cognitive evaluation and informant-based report on participant’s HD that interfere significantly with daily activities at baseline and for every 15 months. Cox proportional hazards models (utilising time-dependent HD status and age as the time scale) were used to examine HD and the risk for MCI or dementia, and mixed-effects models (allowing for random subject-specific intercepts and slopes) were used to examine the relationship between HD and cognitive decline.Results: about, 981 participants had HD and 612 (12.7%) had prevalent MCI at baseline; 759 participants developed incident MCI and 273 developed incident dementia. In cognitively unimpaired participants at baseline, those with HD had higher risk for MCI (hazard ratio [HR] = 1.29, 95% confidence interval [CI] (1.10, 1.51), P = 0.002; adjusting for sex, years of education). In participants without dementia, those with HD had higher risk for dementia (HR: 1.39, 95% CI, (1.08–1.79), P = 0.011; adjusting sex and education). In individuals with MCI, HD was associated with modestly greater cognitive decline.Conclusions: informant-based HD was associated with increased risk for MCI and dementia.
Foraging ecology influences the number of vertebrae in hydrophiine sea snakes
Authors: Hampton Paul M 
Published: July 2019

Abstract
The number of vertebrae in snakes is highly variable both within and among species. Across ophidian taxa, the number of vertebrae has been linked to many aspects of ecology and performance. Herein, I test the hypothesis that variation in the number of vertebrae and the length of the anterior region of sea snakes are associated with foraging ecology. I predicted that sea snakes that invade burrows and crevices for prey would have relatively longer anterior regions as a result of a greater number of vertebrae. Using radiographs, I counted the number of vertebrae between the head and atria and between the atria and cloaca for 22 species of hydrophiine sea snakes. The length between the cranium and atria was positively associated with the frequency of burrowing prey consumed. The number of vertebrae in the pre-atrial region showed a positive association with diet, although the analysis only approached statistical significance. No association was observed between diet and the number of vertebrae between the atria and cloaca, indicating that heart position is constrained with respect to the cloaca. These data indicate that sea snakes specializing on burrowing prey have adapted elongated, anterior regions of the body through an increased number of vertebrae.
Patterns of retrograde axonal degeneration in the visual system
Authors: de Vries-Knoppert Willemien A , Baaijen Johannes C , Petzold Axel 
Published: July 2019

Abstract
Conclusive evidence for existence of acquired retrograde axonal degeneration that is truly trans-synaptic (RTD) has not yet been provided for the human visual system. Convincing data rely on experimental data of lesions to the posterior visual pathways. This study aimed to overcome the limitations of previous human studies, namely pathology to the anterior visual pathways and neurodegenerative co-morbidity. In this prospective, longitudinal cohort retinal optical coherence tomography scans were acquired before and after elective partial temporal lobe resection in 25 patients for intractable epilepsy. Newly developed region of interest-specific, retinotopic areas substantially improved on conventional reported early treatment diabetic retinopathy study (ETDRS) grid-based optical coherence tomography data. Significant inner retinal layer atrophy separated patients with normal visual fields from those who developed a visual field defect. Acquired RTD affected the retinal nerve fibre layer, ganglion cell and inner plexiform layer and stopped at the level of the inner nuclear layer. There were significant correlations between the resected brain tissue volume and the ganglion cell layer region of interest (R = −0.78, P < 0.0001) and ganglion cell inner plexiform layer region of interest (R = −0.65, P = 0.0007). In one patient, damage to the anterior visual pathway resulted in occurrence of microcystic macular oedema as recognized from experimental data. In the remaining 24 patients with true RTD, atrophy rates in the first 3 months were strongly correlated with time from surgery for the ganglion cell layer region of interest (R = −0.74, P < 0.0001) and the ganglion cell inner plexiform layer region of interest (R = −0.51, P < 0.0001). The different time course of atrophy rates observed relate to brain tissue volume resection and suggest that three distinct patterns of retrograde axonal degeneration exist: (i) direct retrograde axonal degeneration; (ii) rapid and self-terminating RTD; and (iii) prolonged RTD representing a ‘penumbra’, which slowly succumbs to molecularly governed spatial cellular stoichiometric relationships. We speculate that the latter could be a promising target for neuroprotection.
Social Mixing and Clinical Features Linked With Transmission in a Network of Extensively Drug-resistant Tuberculosis Cases in KwaZulu-Natal, South Africa
Authors: Nelson Kristin N , Jenness Samuel M , Mathema Barun , Lopman Benjamin A , Auld Sara C , Shah N Sarita , Brust James C M , Ismail Nazir , Omar Shaheed Vally , Brown Tyler S , Allana Salim , Campbell Angie , Moodley Pravi , Mlisana Koleka , Gandhi Neel R 
Published: July 2019

Abstract

Background
Tuberculosis (TB) is the leading infectious cause of death globally, and drug-resistant TB strains pose a serious threat to controlling the global TB epidemic. The clinical features, locations, and social factors driving transmission in settings with high incidences of drug-resistant TB are poorly understood.

Methods
We measured a network of genomic links using Mycobacterium tuberculosis whole-genome sequences.

Results
Patients with 2–3 months of cough or who spent time in urban locations were more likely to be linked in the network, while patients with sputum smear–positive disease were less likely to be linked than those with smear-negative disease. Associations persisted using different thresholds to define genomic links and irrespective of assumptions about the direction of transmission.

Conclusions
Identifying factors that lead to many transmissions, including contact with urban areas, can suggest settings instrumental in transmission and indicate optimal locations and groups to target with interventions.
Outcomes of Immunocompromised Adults Hospitalized With Laboratory-confirmed Influenza in the United States, 2011–2015
Authors: Collins Jennifer P , Campbell Angela P , Openo Kyle , Farley Monica M , Cummings Charisse Nitura , Hill Mary , Schaffner William , Lindegren Mary Lou , Thomas Ann , Billing Laurie , Bennett Nancy , Spina Nancy , Bargsten Marisa , Lynfield Ruth , Eckel Seth , Ryan Patricia , Yousey-Hindes Kimberly , Herlihy Rachel , Kirley Pam Daily , Garg Shikha , Anderson Evan J 
Published: July 2019

Abstract

Background
Hospitalized immunocompromised (IC) adults with influenza may have worse outcomes than hospitalized non-IC adults.

Methods
We identified adults hospitalized with laboratory-confirmed influenza during 2011–2015 seasons through CDC’s Influenza Hospitalization Surveillance Network. IC patients had human immunodefiency virus (HIV)/AIDS, cancer, stem cell or organ transplantation, nonsteroid immunosuppressive therapy, immunoglobulin deficiency, asplenia, and/or other rare conditions. We compared demographic and clinical characteristics of IC and non-IC adults using descriptive statistics. Multivariable logistic regression and Cox proportional hazards models controlled for confounding by patient demographic characteristics, pre-existing medical conditions, influenza vaccination, and other factors.

Results
Among 35 348 adults, 3633 (10%) were IC; cancer (44%), nonsteroid immunosuppressive therapy (44%), and HIV (18%) were most common. IC patients were more likely than non-IC patients to have received influenza vaccination (53% vs 46%; P &lt; .001), and ~85% of both groups received antivirals. In multivariable analysis, IC adults had higher mortality (adjusted odds ratio [aOR], 1.46; 95% confidence interval [CI], 1.20–1.76). Intensive care was more likely among IC patients 65–79 years (aOR, 1.25; 95% CI, 1.06–1.48) and those &gt;80 years (aOR, 1.35; 95% CI, 1.06–1.73) compared with non-IC patients in those age groups. IC patients were hospitalized longer (adjusted hazard ratio of discharge, 0.86; 95% CI, .83–.88) and more likely to require mechanical ventilation (aOR, 1.19; 95% CI, 1.05–1.36).

Conclusions
Substantial morbidity and mortality occurred among IC adults hospitalized with influenza. Influenza vaccination and antiviral administration could be increased in both IC and non-IC adults.
New opportunities for targeting redox dysregulation in cardiovascular disease
Authors: Bubb Kristen J , Drummond Grant R , Figtree Gemma A 
Published: July 2019

Abstract
Despite substantial promise, the use of antioxidant therapy to improve cardiovascular outcomes has been disappointing. Whilst the fundamental biology supporting their use continues to build, the challenge now is to differentially target dysregulated redox signalling domains and to identify new ways to deliver antioxidant substances. Looking further afield to other disciplines, there is an emerging ‘tool-kit’ containing sophisticated molecular and drug delivery applications. Applying these to the cardiovascular redox field could prove a successful strategy to combat the increasing disease burden. Excessive reactive oxygen species production and protein modifications in the mitochondria has been the target of successful drug development with several positive outcomes emerging in the cardiovascular space, harnessing both improved delivery mechanisms and enhanced understanding of the biological abnormalities. Using this as a blueprint, similar strategies could be applied and expanded upon in other redox-hot-spots, such as the caveolae sub-cellular region, which houses many of the key cardiovascular redox proteins such as NADPH oxidase, endothelial nitric oxide synthase, angiotensin II receptors, and beta adrenoceptors. The expanded tool kit of drug development, including gene and miRNA therapies, nanoparticle technology and micropeptide targeting, can be applied to target dysregulated redox signalling in subcellular compartments of cardiovascular cells. In this review, we consider the opportunities for improving cardiovascular outcomes by utilizing new technology platforms to target subcellular ‘bonfires’ generated by dysregulated redox pathways, to improve clinical outcomes.