bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and technological aspects of functionally oriented technology of manufacturing the three-cone drill bits
Authors: Slipchuk A M , Jakym R S , Korendiy V M , Lytvyniak Y M
Published: March 2023

The quality and efficiency of the drilling process significantly depend on the design parameters and operational peculiarities of the drill bit cutter. The present paper is focused on developing the functionally oriented technology of manufacturing the three-cone drill bits. The research methodology involves the theoretical and experimental studies dedicated to analysing the main reasons for the loss of the cutters working capacity, and the technological factors that affect the strength and durability of the “tooth – cutter” press connection. The major scientific novelty consists in defining the relationships between the design parameters of the cutters, their kinematics, dynamics, and operational conditions. It has been established that the destruction of the rock by the three-cone drill bits is carried out by applying successive impacts of the tipped hard-alloyed teeth upon the rock. The rolling of the cutters (bits) along a face (stope) exerts a dynamic effect due to the alternate change of the contact of the teeth with the rock, and the axial load on the bit ensures that the striking part of the teeth is pressed into the rock. The character of wear and destruction of the tipped teeth also has an important influence. During the drilling process, the rock-destructing parts (teeth), as well as the working areas of the cutters, undergo intensive wear and failure. This leads to a significant decrease in the quality of the rock destruction process and a reduction in the drilling efficiency. The obtained results have a significant practical value and can be effectively used by designers, technologists and researchers while implementing the energy-efficient drilling technologies.
Development of the material homogeneity criterion for the analysis of processes of technological inheritability for quality parameters of machine parts
Authors: Kusyi Ya M , Onysko O R , Kuk A M , Zinko A V
Published: March 2023

The material homogeneity criterion and the indicators characterized by this criterion were developed due to the LM-hardness method. The research results were tried out during the manufacturing of steel shaft. The values of the Weibull homogeneity coefficient during shaft’s machining increase from 6.12-11.46 (for initial workpiece) to 198.23-344.59 (for finish part) during its manufacturing. Besides the constant of the material Am in the manufacturing chain “initial workpiece – finish part” changes from 0.814 to 0.966 for different necks of the shaft during its machining by cutting and abrasive methods. The elaborated method can be used when manufacturing and operation of different mechanical engineering parts for analysis of the change of their material homogeneity during machining, control and determining of their residual life.
Analytical study of heat transfer through friction overlay of band-pad brakes
Authors: Pazen O Y , Tatsiy R M , Ya Ropyak L , Vytvytskyi V S
Published: March 2023

The paper analyses the operating conditions of band-pad brakes of drilling winch, materials and coatings for strengthening the metal elements of friction pairs. Methods of researching the thermal and stress-strain state of elements of brake friction units are considered. The problem of the development and theoretical research of the properties of new polymer materials with gradient properties for the production of friction overlays of band-pad brakes with improved operational characteristics is singled out. A mathematical model heat transfer through friction overlays of band-pad brakes of drilling winches with a variable coefficient of thermal conductivity of the material based on the thickness of the specified overlays has been developed. According to the developed mathematical model, an analytical study of the process of heat transfer through the friction overlays of band-pad with variable coefficient of thermal conductivity of their polymer material according to the thickness of the friction overlays was carried out according to different laws. It was established that the highest intensity of heat removal from the friction zone of the brakes is ensured when the thermal conductivity coefficient changes according to the law described by a second-order polynomial.
To the question of mathematical modeling of the crushed wood particles movement in pneumatic transport and aspiration systems
Authors: Liashenyk A V , Udovytskyi O M , Dorundiak L M , Udovytska M V
Published: March 2023

Transport pneumatic systems (TPS) are widely used in various branches of industries. The transportation of crushed material in such systems is carried out due to the air flow. In the woodworking industry, there are technological processes that are often accompanied by the formation of dust and other small air pollutants. Studying the movement of particles in polluted air makes it possible to transport or separate such particles, while spending less energy. In this paper, the mathematical model of the movement of dusty air containing separate solid particles (production waste) was worked out, and based on it, solution will allow to separate and capture crushed wood particles and to reduce the cost of consumed electricity for transportation is proposed.
The influence of the design of the upper cover of the cyclone on its characteristics
Authors: Maistruk V V
Published: March 2023

An analysis of the works in which the designs of widespread dust-capturing devices are studied. It has been established that the prediction of the operation of dust-collecting devices in certain conditions is most effectively carried out by the methods of numerical modeling and simulation of the separation process, which are widely used for the research of devices of this type. With the help of numerical modeling methods, the structure of the gas flow in the cyclone for different designs of the top cover, the influence of the gas flow velocity in the inlet nozzle on the hydraulic resistance of the device and compared it with experimental data were determined.
Rational choice of torques distribution between the front and back electric motors of automobile wheels drive
Authors: Podryhalo M , Kaidalov R , Omelchenko V
Published: March 2023

Two-axle all-wheel drive automobiles and the procedure for determining the torques between the front and back driving wheels are considered. The influence of the distribution of torques between the front and back driving wheels of all-wheel drive two-axle automobiles on their controllability, stability and energy efficiency is analyzed. A study was conducted to improve the energy efficiency of two-axle automobiles by rationally choosing the torque distribution coefficient between the front and back wheels. A mathematical model of the efficiency ratio of the wheel drive of a two-axle automobile was obtained, which makes it possible to determine the ratio of the rational distribution of torques between the front and back wheels through its optimization. It has been proven that the use of electric automobiles and automobiles with a combined power unit will allow to control the distribution of torques between their front and back wheels controlled by electric motors. The proposed rational choice of the distribution of torques between the front and rear electric motors of the wheel drive will allow to increase the efficiency of the wheel drive and improve the energy efficiency not only of single electric automobiles and hybrid automobiles, but also of road trains that use a combined electromechanical drive of the driving wheels.
Modeling of three-link road trains
Authors: Zinko R , Lanets O , Skvarok Y
Published: March 2023

It is proposed to use graphs for developing the mathematical model of multi-link road trains with coupling devices of different designs. The calculation scheme is formed on the basis of the structure graph of the multi-link road train construction scheme. Next, the structure graph of the mathematical model generalized coordinates levels is written. This allows to develop the mathematical model of appropriate complexity depending on the research objectives. The developed mathematical motion model of a multi-link road train with an elastic-damping joints of their main elements was represented by a system of nonlinear inhomogeneous ordinary differential equations of the second order. The acceleration process for three-link road train with pneumatic coupling devices between train links was modeled.
Mathematical model of agricultural aggregate movement based on the Autotractor
Authors: Adamchuk V V , Pohoriliy S P , Prysiazhnyi V G , Yu Mirnyi V
Published: March 2023

The paper presents theoretical studies of the movement of the agricultural unit on the basis of the MEZ-330 «Autotractor». An equivalent dynamic model of an agricultural unit on the basis of MEZ-330 «Autotractor» is presented. A system of differential equations has been compiled, which makes it possible to describe the interrelation of the main structural parameters of the unit and its operating modes. The results of modeling the motion of the MEZ-330 «Autotractor» on the implementation of technological operations are given. According to the simulation results, the dependences describing the influence of the mass of the MEZ-330 «Autotractor» on the coefficient of slipping of its wheels were established. It is established that the obtained theoretical dependences are adequate and correlate with experimental data with a 95% confidence probability.
Comparative assessment of the efficiency of some car drives
Authors: Rudyk Y , Gavryliyk A , Kuts V , Yatsuk V , Vinogradov S
Published: March 2023

The fundamental basis for the scientific progress is the cheaper technology. Systems analysis and engineering, decision-making systems are based on data completeness and their validation. The study aims to provide the following grounds for a systematic comparison of economic and environmental performance of vehicles with different fuel drives. The issue of logistical attractiveness and compatibility for Ukraine is especially relevant today. Thus, specific fuel consumption is calculated by determining the cost of electricity that goes to charge the traction battery from the mains and is equivalently converted into the cost of fuel. The paper presents a method of calculating the equivalent fuel consumption for electric vehicles according to European (l per 100 km) and American standards (miles per 1 gallon). According to the results of fuel efficiency studies, it is established that the equivalent fuel consumption on the territory of Ukraine of the studied electric vehicles is 8-10 times lower than the fuel consumption of cars of the same class with internal combustion engines.
Computation of Tense-Deformed State of the Die Mold Matrix
Authors: Velyka O.T. , Bojko M. V. , Velykyj N.-T. I.
Published: March 2023

A method of computation of the tense-deformed state of the die mold matrix is described in the given article. Using the criterion of the same durability an algorithm of minimization of its weight is built after the structural parameters. The stress-strain state of the matrix was calculated in the AUTODESK INVENTOR . Research and analysis of the stress-strain state of the matrix was carried out and its optimal parameters were determined. As a result, it makes it possible to optimize the structure of the matrix in terms of stiffness and stability and ensure its optimal performance
Study of microclimate parameters in the bus driver’s cabin in the warm season
Authors: Voichyshyn Yurii , Holenko Kostyantyn , Roman Dmytro , Horbai Orest
Published: March 2023

Work describes an approach to complex thermal analysis of buses salons starting from engine heat radiation and with its further distribution along the internal bus volume. Provided workflow chain in the article could be used as the base for any bus type climate and thermal investigation with the next optimization events. Heat analysis with materials thermal conductivity parameters was proceeded using Ansys Fluent and Ansys Steady State Thermal addons. Based on the obtained results, it is possible to draw conclusions about the impact of different parameters (temperature, heat radiation, humidity, etc) on the buses salons microclimate. Presented work could be much actual in practical plane like methodology used for efficient bus bodies development by engineers who could apply suggested materials for calculating the distribution of heat from the engine in the passenger compartment of the bus and studying the microclimate in different operating conditions. That could be especially valuable at the stage of the new bus models design and modelling.
Graphdiyne (C
n
H2n−2) based S-scheme heterojunction to promote carrier transfer for efficiently photocatalytic hydrogen evolution
Authors: Jin Zhiliang , Wang Xuanpu , Wu Youlin , Li Teng
Published: March 2023

Graphdiyne (GDY) is a new carbon allotrope with excellent properties due to its unique structure and highly conjugated system. In this work, GDY/CuMoO4 (CMO)/CuO tandem S-scheme heterojunction was constructed using the cross-coupling method. Among them, CuI is not only used as a coupling catalyst to obtain easily collected GDY, but also as a precursor for more active composite catalysts. 2D GDY provides a substrate for the loading of CMO and CuO, while the highly conjugated system and excellent electrical conductivity allow the composites to form a unique system with strong charge distribution and transport. The step-by-step progressive S-scheme heterojunctions constructed based on the one-step calcination strategy have stronger reducing activity and carrier transfer capability. The intrinsic charge transfer mechanism of the catalyst was investigated by photoelectrochemical characterization and in situ x-ray photoelectron spectroscopy analysis, and the mechanism of the photocatalytic hydrogen production reaction was proposed. This work provides a viable approach for the development of GDY in photocatalysis and the design of S-scheme heterojunctions.
A robust estimator of mutual information for deep learning interpretability
Authors: Piras Davide , Peiris Hiranya V , Pontzen Andrew , Lucie-Smith Luisa , Guo Ningyuan , Nord Brian
Published: March 2023

We develop the use of mutual information (MI), a well-established metric in information theory, to interpret the inner workings of deep learning (DL) models. To accurately estimate MI from a finite number of samples, we present GMM-MI (pronounced ‘Jimmie’), an algorithm based on Gaussian mixture models that can be applied to both discrete and continuous settings. GMM-MI is computationally efficient, robust to the choice of hyperparameters and provides the uncertainty on the MI estimate due to the finite sample size. We extensively validate GMM-MI on toy data for which the ground truth MI is known, comparing its performance against established MI estimators. We then demonstrate the use of our MI estimator in the context of representation learning, working with synthetic data and physical datasets describing highly non-linear processes. We train DL models to encode high-dimensional data within a meaningful compressed (latent) representation, and use GMM-MI to quantify both the level of disentanglement between the latent variables, and their association with relevant physical quantities, thus unlocking the interpretability of the latent representation. We make GMM-MI publicly available in this GitHub repository.
Comparison of Microfat, Nanofat, and Extracellular Matrix/Stromal Vascular Fraction Gel for Skin Rejuvenation: Basic Animal Research
Authors: Yang Zhibin , Dong Liangyan , Jin Shengyang , Han Xuefeng , Li Facheng
Published: March 2023

Background

Although stromal vascular fraction (SVF) cells and adipose-derived stem cells have well-defined antiaging effects on skin, certain disadvantages have limited their clinical application.

Objectives

The aim of this study was to evaluate the effects of microfat, nanofat, and SVF-gel in improving ultraviolet (UV)-induced photoaged skin injury in nude mice.

Methods

After successfully establishing a photoaging model by UVA and UVB irradiation in nude mice, the back of each mouse was divided into 2 regions and randomly injected under the dermis with 0.5 mL of microfat, nanofat, SVF-gel, and phosphate-buffered saline. Inflammatory infiltration, dermis thickness, hydroxyproline content, Type I/Type III collagen ratio, elastic fiber morphology, skin cell proliferation, and adipocyte viability were measured. The overall structure of the skin was also observed by scanning electron microscopy.

Results

In the microfat group, the grafts survived well, with intact structure and viable adipocytes and little infiltration of inflammatory cells. Microfat promoted skin cell proliferation, collagen content increased, the ratio of Type I and III collagen reversed, and new oxytalan fibers formed, which to some extent improved the photoaging skin. In the nanofat and SVF-gel groups, a large amount of inflammatory cell infiltration and foam cell deposition in the grafts and dermis led to fibrosis and proliferation of skin tissue. Although the skin thickness and collagen content were also increased, these factors did not improve the photoaging skin.

Conclusions

Microfat survives well, and improves photoaged skin injury in nude mice by promoting skin tissue regeneration and supplementing the capacity of subcutaneous adipose tissue.
Battle for space: statecraft, diplomacy and defence strategy
Authors: Smith James
Published: March 2023

James W. E. Smith considers the changing perspectives on the role of space for the military
vaRHC: an R package for semi-automation of variant classification in hereditary cancer genes according to ACMG/AMP and gene-specific ClinGen guidelines
Authors: Munté Elisabet , Feliubadaló Lidia , Pineda Marta , Tornero Eva , Gonzalez Maribel , Moreno-Cabrera José Marcos , Roca Carla , Bales Rubio Joan , Arnaldo Laura , Capellá Gabriel , Mosquera Jose Luis , Lázaro Conxi
Published: March 2023

Motivation

Germline variant classification allows accurate genetic diagnosis and risk assessment. However, it is a tedious iterative process integrating information from several sources and types of evidence. It should follow gene-specific (if available) or general updated international guidelines. Thus, it is the main burden of the incorporation of next-generation sequencing into the clinical setting.

Results

We created the vaRiants in HC (vaRHC) R package to assist the process of variant classification in hereditary cancer by: (i) collecting information from diverse databases; (ii) assigning or denying different types of evidence according to updated American College of Molecular Genetics and Genomics/Association of Molecular Pathologist gene-specific criteria for ATM, CDH1, CHEK2, MLH1, MSH2, MSH6, PMS2, PTEN, and TP53 and general criteria for other genes; (iii) providing an automated classification of variants using a Bayesian metastructure and considering CanVIG-UK recommendations; and (iv) optionally printing the output to an .xlsx file. A validation using 659 classified variants demonstrated the robustness of vaRHC, presenting a better criteria assignment than Cancer SIGVAR, an available similar tool.

Availability and implementation

The source code can be consulted in the GitHub repository (https://github.com/emunte/vaRHC) Additionally, it will be submitted to CRAN soon.
Prediction and curation of missing biomedical identifier mappings with Biomappings
Authors: Hoyt Charles Tapley , Hoyt Amelia L , Gyori Benjamin M
Published: March 2023

Motivation

Biomedical identifier resources (such as ontologies, taxonomies, and controlled vocabularies) commonly overlap in scope and contain equivalent entries under different identifiers. Maintaining mappings between these entries is crucial for interoperability and the integration of data and knowledge. However, there are substantial gaps in available mappings motivating their semi-automated curation.

Results

Biomappings implements a curation workflow for missing mappings which combines automated prediction with human-in-the-loop curation. It supports multiple prediction approaches and provides a web-based user interface for reviewing predicted mappings for correctness, combined with automated consistency checking. Predicted and curated mappings are made available in public, version-controlled resource files on GitHub. Biomappings currently makes available 9274 curated mappings and 40 691 predicted ones, providing previously missing mappings between widely used identifier resources covering small molecules, cell lines, diseases, and other concepts. We demonstrate the value of Biomappings on case studies involving predicting and curating missing mappings among cancer cell lines as well as small molecules tested in clinical trials. We also present how previously missing mappings curated using Biomappings were contributed back to multiple widely used community ontologies.

Availability and implementation

The data and code are available under the CC0 and MIT licenses at https://github.com/biopragmatics/biomappings.
Early blood neurofilament light chain and myelin oligodendrocyte glycoprotein antibody levels associate with different disease courses of myelin oligodendrocyte glycoprotein-associated disease in children
Authors: Horellou Philippe , Flet-Berliac Lorraine , Leroy Carole , Giorgi Laetitia , Joly Candie , Desjardins Delphine , Chrétien Pascale , Hacein-Bey-Abina Salima , Le Grand Roger , Deiva Kumaran
Published: March 2023

Acquired demyelinating syndrome associated with myelin oligodendrocyte glycoprotein antibodies, named recently myelin oligodendrocyte glycoprotein-associated disease, represents >27% of this paediatric syndrome. Relapses occur in 40% of them, which may be associated with severe outcomes. Aiming to identify biomarker allowing to predict relapse, we measured both myelin oligodendrocyte glycoprotein antibodies and neurofilament light chain levels in blood samples of patients that are known to reflect axonal injuries in neurological diseases including demyelinating autoimmune disorders. Three groups of patients were selected: relapsing myelin oligodendrocyte glycoprotein-associated disease (n = 8), non-relapsing myelin oligodendrocyte glycoprotein-associated disease (n = 7) and control patients with non-inflammatory neurological diseases (n = 12). Neurofilament light chain concentrations were measured in plasma of these three groups of patients using the high-sensitivity single-molecule array method at onset of the disease and 6 months later. At onset of the disease, we found that levels of neurofilament light chain in blood of non-relapsing patients were significantly higher than in control patients (means: 98.36 ± 22.66 versus 12.47 ± 2.47 pg/mL, **P < 0.01, Kruskal–Wallis test). The mean neurofilament light chain value in relapsing patients (82.16 ± 38.41 pg/mL) was not significantly different from that in non-relapsing and in control patients. Plasma myelin oligodendrocyte glycoprotein antibody levels were 2.5-fold higher in relapsing than in non-relapsing patients without reaching significance (means: 15.26 ± 4.87 versus 5.96 ± 1.13; two-tailed Mann–Whitney U-test P = 0.119). Plasma neurofilament light chain correlated significantly with myelin oligodendrocyte glycoprotein antibody levels in relapsing (two-tailed Spearman r = 0.8, P = 0.0218) but not in non-relapsing (two-tailed Spearman r = 0.17, P = 0.71). Interestingly, the ratio of neurofilament light chain-to-myelin oligodendrocyte glycoprotein antibodies was significantly lower in relapsing than in non-relapsing patients (means: 5.19 ± 1.61 versus 21.87 ± 6.13; two-tailed Mann–Whitney U-test P = 0.014). These findings suggest that measuring both neurofilament light chain and myelin oligodendrocyte glycoprotein antibody levels in patients at onset of demyelinating disease could predict relapse of myelin oligodendrocyte glycoprotein-associated disease.
Searching in the maze: sodium–glucose cotransporter-2 inhibitors in kidney transplant recipients to improve survival
Authors: Oliveras Laia , Montero Núria , Cruzado Josep M
Published: March 2023

Sodium–glucose cotransporter-2 inhibitors (SGLT2is) improve cardiovascular and renal outcomes in chronic kidney disease patients with and without diabetes. Kidney transplant recipients have been excluded from landmark trials using SGLT2is and literature on safety and efficacy are scarce. Recent studies suggest that the SGLT2i use in kidney transplant recipients with diabetes is safe, paving the way to investigate whether SGLT2is could also reduce cardiovascular events and kidney function deterioration in kidney allograft recipients.
AFTM: a database of transmembrane regions in the human proteome predicted by AlphaFold
Authors: Pei Jimin , Cong Qian
Published: March 2023

Transmembrane proteins (TMPs), with diverse cellular functions, are difficult targets for structural determination. Predictions of TMPs and the locations of transmembrane segments using computational methods could be unreliable due to the potential for false positives and false negatives and show inconsistencies across different programs. Recent advances in protein structure prediction methods have made it possible to identify TMPs and their membrane-spanning regions using high-quality structural models. We developed the AlphaFold Transmembrane proteins (AFTM) database of candidate human TMPs by identifying transmembrane regions in AlphaFold structural models of human proteins and their domains using the positioning of proteins in membranes, version 3 program, followed by automatic corrections inspired by manual analysis of the results. We compared our results to annotations from the UniProt database and the Human Transmembrane Proteome (HTP) database. While AFTM did not identify transmembrane regions in some single-pass TMPs, it identified more transmembrane regions for multipass TMPs than UniProt and HTP. AFTM also showed more consistent results with experimental structures, as benchmarked against the Protein Data Bank Transmembrane proteins (PDBTM) database. In addition, some proteins previously annotated as TMPs were suggested to be non-TMPs by AFTM. We report the results of AFTM together with those of UniProt, HTP, TmAlphaFold, PDBTM and Membranome in the online AFTM database compiled as a comprehensive resource of candidate human TMPs with structural models.

Database URL http://conglab.swmed.edu/AFTM
Diastolic delta best predicts paravalvular regurgitation after transcatheter aortic valve replacement as assessed by cardiac magnetic resonance: the APPOSE trial
Authors: Rooijakkers Maxim J P , Stens Niels A , van Wely Marleen H , van der Wulp Kees , Rodwell Laura , Gehlmann Helmut , van Garsse Leen A F M , Geuzebroek Guillaume S C , Verkroost Michel W A , Habets Jesse , El Messaoudi Saloua , Thijssen Dick H J , Nijveldt Robin , van Royen Niels
Published: March 2023

Aims

Paravalvular regurgitation (PVR) is a common complication after transcatheter aortic valve replacement (TAVR) that poses an increased risk of rehospitalization for heart failure and mortality. The aim of this study was to assess the accuracy of haemodynamic indices to predict relevant PVR.

Methods and results

In this prospective single-centre clinical trial, four haemodynamic indices of PVR measured during TAVR were assessed for their correlation with gold standard cardiac magnetic resonance (CMR)-derived regurgitant fraction (CMR-RF) at 1 month follow-up: diastolic delta (DD), heart rate-adjusted diastolic delta (HR-DD), aortic regurgitation index (ARI), and aortic regurgitation index ratio (ARI ratio). These haemodynamic indices were analysed for their ability to predict relevant PVR (defined as CMR-RF > 20%) using receiver operating characteristic (ROC) curves with corresponding area under the ROC curves (AUCs). A total of 77 patients were included and had CMR performed 41 ± 14 days after TAVR. Mean CMR-RF was 12.4 ± 9.3%. Fifteen (19.5%) patients had CMR-RF > 20%. DD had the best correlation with CMR-RF and the highest AUC to predict relevant PVR (0.82; 95% CI, 0.72–0.92), followed by HR-DD (AUC 0.78; 95% CI, 0.67–0.89), ARI (AUC 0.78; 95% CI, 0.66–0.89), and ARI ratio (AUC 0.65; 95% CI, 0.49–0.81). The optimal cut-off value for DD was 32 mmHg, with sensitivity of 69% and specificity of 77% in predicting relevant PVR.

Conclusion

DD measured during TAVR best predicts relevant PVR. Correction for heart rate (HR-DD) or systolic blood pressure (ARI, ARI ratio) did not improve this predictive value.
Extracellular volume fraction (ECV) derived from pre-operative computed tomography predicts prognosis in patients undergoing transcatheter aortic valve implantation (TAVI)
Authors: Vignale Davide , Palmisano Anna , Gnasso Chiara , Margonato Davide , Romagnolo Davide , Barbieri Simone , Ingallina Giacomo , Stella Stefano , Ancona Marco Bruno , Montorfano Matteo , Maisano Francesco , Agricola Eustachio , Esposito Antonio
Published: March 2023

Aims

Transcatheter aortic valve implantation (TAVI) is the treatment of choice for high-risk patients with severe aortic stenosis (AS). A portion of TAVI recipients has no long-term clinical benefit, and myocardial fibrosis may contribute to unfavourable outcomes. We aimed to assess the prognostic value of an interstitial fibrosis marker, extracellular volume fraction (ECV), measured at planning computed tomography (CT) before TAVI.

Methods and results

From October 2020 to July 2021, 159 consecutive patients undergoing TAVI planning CT were prospectively enroled. ECV was calculated as the ratio of myocardium and blood pool differential attenuations before and 5 min after contrast administration, pondered for haematocrit. A composite endpoint including heart failure hospitalization (HFH) and death was collected by telehealth or in-person follow-up visits in the 113 patients constituting the final study population. Cox proportional hazards model was used to assess association between ECV and the composite endpoint.

Median follow-up was 13 (11–15) months. The composite endpoint occurred in 23/113 (20%) patients. These patients had lower aortic valve mean pressure gradient [39 (29–48) vs. 46 (40–54) mmHg, P = 0.002] and left ventricular and right ventricular ejection fraction [51 (37–69) vs. 66 (54–74)%, P = 0.014; 45 (31–53) vs. 49 (44–55)%, P = 0.010] and higher ECV [31.5 (26.9–34.3) vs. 27.8 (25.3–30.2)%, P = 0.006]. At multivariable Cox analysis, ECV higher than 31.3% was associated to increased risk of death or HFH at follow-up (hazard ratio = 5.92, 95% confidence interval 2.37–14.75, P < 0.001).

Conclusion

In this prospective observational cohort study, ECV measured at TAVI planning CT predicts the composite endpoint (HFH or death) in high-risk severe AS patients.
A Highly Contiguous and Annotated Genome Assembly of the Lesser Prairie-Chicken (Tympanuchus pallidicinctus)
Authors: Black Andrew N , Bondo Kristin J , Mularo Andrew , Hernandez Alvaro , Yu Yachi , Stein Carleigh M , Gregory Andy , Fricke Kent A , Prendergast Jeff , Sullins Dan , Haukos David , Whitson Michael , Grisham Blake , Lowe Zach , DeWoody J Andrew
Published: March 2023

The Lesser Prairie-Chicken (Tympanuchus pallidicinctus; LEPC) is an iconic North American prairie grouse, renowned for ornate and spectacular breeding season displays. Unfortunately, the species has disappeared across much of its historical range, with corresponding precipitous declines in contemporary population abundance, largely due to climatic and anthropogenic factors. These declines led to a 2022 US Fish and Wildlife decision to identify and list two distinct population segments (DPSs; i.e., northern and southern DPSs) as threatened or endangered under the 1973 Endangered Species Act. Herein, we describe an annotated reference genome that was generated from a LEPC sample collected from the southern DPS. We chose a representative from the southern DPS because of the potential for introgression in the northern DPS, where some populations hybridize with the Greater Prairie-Chicken (Tympanuchus cupido). This new LEPC reference assembly consists of 206 scaffolds, an N50 of 45 Mb, and 15,563 predicted protein-coding genes. We demonstrate the utility of this new genome assembly by estimating genome-wide heterozygosity in a representative LEPC and in related species. Heterozygosity in a LEPC sample was 0.0024, near the middle of the range (0.0003–0.0050) of related species. Overall, this new assembly provides a valuable resource that will enhance evolutionary and conservation genetic research in prairie grouse.
Telecaregiving for Dementia: A Mapping Review of Technological and Nontechnological Interventions
Authors: Hill Jordan R , Min Elissa E , Abebe Ephrem , Holden Richard J
Published: March 2023

Background and Objectives

Informal (or family) caregivers to older adults with Alzheimer’s disease or other related dementias (ADRD) could greatly benefit from innovative telecaregiving systems that support caregiving from a distance. The objective of this review is to better understand (a) who is involved in telecaregiving and their experiences; (b) the interventions currently available to support ADRD telecaregiving; and (c) the outcomes measured to assess the effects of ADRD telecaregiving interventions.

Research Design and Methods

A mapping review was conducted by systematically searching MEDLINE, CINAHL, Embase, and PsycINFO for all works published in English from 2002 to 2022. References of included publications were searched to identify additional empirical publications for inclusion.

Results

Sixty-one publications (describing 48 studies and 5 nonstudy sources) were included in the review. Currently available information on the demographics, experiences, challenges, and benefits of ADRD telecaregivers is summarized. We found that interventions to support telecaregiving could be classified into 7 categories of technological interventions and 3 categories of nontechnological interventions. Empirical studies on ADRD telecaregiving interventions investigated a variety of outcomes, the most prevalent being user experience.

Discussion and Implications

We conclude that (a) the paucity of literature on telecaregiving does not allow for a comprehensive understanding of the needs and day-to-day activities of ADRD telecaregivers; (b) interventions developed to support ADRD telecaregiving may not fully meet the needs of caregivers or care recipients; and (c) there is insufficient rigorous research establishing the effects of telecaregiving interventions on key ADRD-related outcomes.
Construction of a new chromosome-scale, long-read reference genome assembly for the Syrian hamster, Mesocricetus auratus
Authors: Harris R Alan , Raveendran Muthuswamy , Lyfoung Dustin T , Sedlazeck Fritz J , Mahmoud Medhat , Prall Trent M , Karl Julie A , Doddapaneni Harshavardhan , Meng Qingchang , Han Yi , Muzny Donna , Wiseman Roger W , O'Connor David H , Rogers Jeffrey
Published: March 2023

Background

The Syrian hamster (Mesocricetus auratus) has been suggested as a useful mammalian model for a variety of diseases and infections, including infection with respiratory viruses such as SARS-CoV-2. The MesAur1.0 genome assembly was generated in 2013 using whole-genome shotgun sequencing with short-read sequence data. Current more advanced sequencing technologies and assembly methods now permit the generation of near-complete genome assemblies with higher quality and greater continuity.

Findings

Here, we report an improved assembly of the M. auratus genome (BCM_Maur_2.0) using Oxford Nanopore Technologies long-read sequencing to produce a chromosome-scale assembly. The total length of the new assembly is 2.46 Gb, similar to the 2.50-Gb length of a previous assembly of this genome, MesAur1.0. BCM_Maur_2.0 exhibits significantly improved continuity, with a scaffold N50 that is 6.7 times greater than MesAur1.0. Furthermore, 21,616 protein-coding genes and 10,459 noncoding genes are annotated in BCM_Maur_2.0 compared to 20,495 protein-coding genes and 4,168 noncoding genes in MesAur1.0. This new assembly also improves the unresolved regions as measured by nucleotide ambiguities, where ∼17.11% of bases in MesAur1.0 were unresolved compared to BCM_Maur_2.0, in which the number of unresolved bases is reduced to 3.00%.

Conclusions

Access to a more complete reference genome with improved accuracy and continuity will facilitate more detailed, comprehensive, and meaningful research results for a wide variety of future studies using Syrian hamsters as models.
The first chromosome-level Fallopia multiflora genome assembly provides insights into stilbene biosynthesis
Authors: Zhao Yujiao , Yang Zhengyang , Zhang Zhongren , Yin Minzhen , Chu Shanshan , Tong Zhenzhen , Qin Yuejian , Zha Liangping , Fang Qingying , Yuan Yuan , Huang Luqi , Peng Huasheng
Published: March 2023

Fallopia multiflora (Thunb.) Harald, a vine belonging to the Polygonaceae family, is used in traditional medicine. The stilbenes contained in it have significant pharmacological activities in anti-oxidation and anti-aging. This study describes the assembly of the F. multiflora genome and presents its chromosome-level genome sequence containing 1.46 gigabases of data (with a contig N50 of 1.97 megabases), 1.44 gigabases of which was assigned to 11 pseudochromosomes. Comparative genomics confirmed that F. multiflora shared a whole-genome duplication event with Tartary buckwheat and then underwent different transposon evolution after separation. Combining genomics, transcriptomics, and metabolomics data to map a network of associated genes and metabolites, we identified two FmRS genes responsible for the catalysis of one molecule of p-coumaroyl-CoA and three molecules of malonyl-CoA to resveratrol in F. multiflora. These findings not only serve as the basis for revealing the stilbene biosynthetic pathway but will also contribute to the development of tools for increasing the production of bioactive stilbenes through molecular breeding in plants or metabolic engineering in microbes. Moreover, the reference genome of F. multiflora is a useful addition to the genomes of the Polygonaceae family.
Individual-level and neighborhood-level shifts in mortality patterns among drug poisoning deaths in a high-density Asian city: a territory-wide, case-only analysis
Authors: Ho Hung Chak , Wong Stanley Sau-Ching , Cheung Chi Wai
Published: March 2023

Background

The shifts in individual-level and neighborhood-level patterns of drug poisoning deaths in a high-density Asian city over time have been underestimated, although they provide essential information for community-based surveillance and interventions.

Methods

A case-only analysis with a 16-y, territory-wide, population-based registry in Hong Kong was applied to compare drug poisoning deaths from 2001 to 2010 with 2011 to 2016. Drug poisoning deaths, deaths from heroin and deaths from other opioids (codeine or morphine) were extracted (ICD codes: T36-T50, T40.1, T40.2). Binomial regressions were used to estimate the shifts in mortality patterns.

Results

Among 3069 drug poisoning deaths, a significant shift in mortality patterns was found despite a decreasing mortality trend in Hong Kong. Overall, drug poisoning deaths shifted towards middle-aged/young-old, widowed/divorced, economically active, white collar and non-local born. Since 2011, more deaths from heroin were in older ages and non-local born, but less were never married and economically inactive. More deaths from other opioids were middle-aged, young-old and divorced. In particular, most decedents shifted towards young-old, especially deaths from other opioids. Compared with deaths during 2001–2010, there were 3.72- and 6.50-fold more deaths from heroin and deaths from other opioids in those aged ≥60 y since 2021 (ORs: 3.72 [2.37, 5.86], 6.50 [3.97, 10.65]), respectively. Additionally, drug poisoning deaths shifted towards areas with less neighborhood deprivation (more high-education individuals and a mix of private/public housing residents), especially deaths from other opioids.

Conclusion

Misuse of registered drugs (e.g. opioid pain relievers) could be a rising trend among vulnerable subpopulations in Hong Kong other than illegal drug use (heroin). Health officials should provide more advice and support on drug information. Specifically, an improved health system with education regarding the appropriate use of registered drugs for medical treatments should be provided to mid-/high-income and local-born individuals.
Phylogenomics reveals within species diversification but incongruence with color phenotypes in widespread orchid bees (Hymenoptera: Apidae: Euglossini)
Authors: Sandoval-Arango Stephania , Branstetter Michael G , Cardoso Carolina F , López-Uribe Margarita M
Published: March 2023

Coloration is an important phenotypic trait for taxonomic studies and has been widely used for identifying insect species and populations. However, coloration can be a poor diagnostic character for insect species that exhibit high polymorphism in this trait, which can lead to over-splitting of taxonomic units. In orchid bees, color variation has been interpreted by different taxonomists as either polymorphism associated with Müllerian mimicry complexes or diagnostic traits for species identification. Despite this uncertainty, integrative approaches that incorporate multiple independent datasets to test the validity of hair coloration as a character that identifies independent evolutionary units have not been used. Here, we use phylogenomic data from Ultraconserved Elements (UCEs) to explore whether color phenotypes in the widespread orchid bee species complexes Eulaema meriana and Eulaema bombiformis (Hymenoptera: Apidae: Euglossini) correspond to independent lineages or polymorphic trait variation within species. We find that lineages within both species are structured according to geography and that color morphs are generally unassociated with evolutionarily independent groups except for populations located in the Atlantic Forest of Brazil. We conclude that there is compelling evidence that E. atleticana and E. niveofasciata are subspecies of E. meriana and E. bombiformis, respectively, and not different species as previously suggested. Therefore, we recognize Eulaema meriana atleticanacomb. n. and Eulaema bombiformis niveofasciatacomb. n. and discuss their morphological characteristics. We make recommendations on the use of color traits for orchid bee taxonomy and discuss the significance of subspecies as evolutionary units relevant for conservation efforts.
Extreme differences in SARS-CoV-2 viral loads among respiratory specimen types during presumed pre-infectious and infectious periods
Authors: Viloria Winnett Alexander , Akana Reid , Shelby Natasha , Davich Hannah , Caldera Saharai , Yamada Taikun , Reyna John Raymond B , Romano Anna E , Carter Alyssa M , Kim Mi Kyung , Thomson Matt , Tognazzini Colten , Feaster Matthew , Goh Ying-Ying , Chew Yap Ching , Ismagilov Rustem F
Published: March 2023

SARS-CoV-2 viral-load measurements from a single-specimen type are used to establish diagnostic strategies, interpret clinical-trial results for vaccines and therapeutics, model viral transmission, and understand virus–host interactions. However, measurements from a single-specimen type are implicitly assumed to be representative of other specimen types. We quantified viral-load timecourses from individuals who began daily self-sampling of saliva, anterior-nares (nasal), and oropharyngeal (throat) swabs before or at the incidence of infection with the Omicron variant. Viral loads in different specimen types from the same person at the same timepoint exhibited extreme differences, up to 109 copies/mL. These differences were not due to variation in sample self-collection, which was consistent. For most individuals, longitudinal viral-load timecourses in different specimen types did not correlate. Throat-swab and saliva viral loads began to rise as many as 7 days earlier than nasal-swab viral loads in most individuals, leading to very low clinical sensitivity of nasal swabs during the first days of infection. Individuals frequently exhibited presumably infectious viral loads in one specimen type while viral loads were low or undetectable in other specimen types. Therefore, defining an individual as infectious based on assessment of a single-specimen type underestimates the infectious period, and overestimates the ability of that specimen type to detect infectious individuals. For diagnostic COVID-19 testing, these three single-specimen types have low clinical sensitivity, whereas a combined throat–nasal swab, and assays with high analytical sensitivity, was inferred to have significantly better clinical sensitivity to detect presumed pre-infectious and infectious individuals.
The Cumulative Effects of Colorism: Race, Wealth, and Skin Tone
Authors: Adames Alexander
Published: March 2023

Researchers have long documented a persistent Black–White gap in wealth. These studies, however, often treat race as a discrete category, eluding its socially constructed nature. As a result, these studies assume that the “effect of race” is consistent across all individuals racialized as Black. Studies that make this assumption potentially obscure heterogeneity in the size of the Black–White wealth gap. Research on skin color stratification suggests that it is possible that the Black–White wealth gap varies by the extent to which a racial subgroup is deemed to fit the broader racial umbrella. In turn, I adopt a more complex operationalization of race that is based on both racial and skin tone appraisals. Drawing on data from the National Longitudinal Survey of Youth 1997, I find that the Black–White wealth gap does vary by the Black skin tone subgroup. Generally, the Black–White gap in assets is smallest when focusing on lighter-skin Black people and largest when focusing on darker-skin Black people. These differences are not only the result of initial disadvantage but also cumulative disadvantage in the rate of wealth accumulation. Lastly, the findings suggest that the Black–White wealth gaps grow at a faster rate than the skin tone wealth gaps. I found that differences were robust to adjustments for parental socioeconomic status, childhood background, and interviewer characteristics. I conclude by discussing the theoretical implications for our understanding of the mechanisms undergirding Black–White disparities in wealth attainment.
Sleep restriction effects on sleep spindles in adolescents and relation of these effects to subsequent daytime sleepiness and cognition
Authors: Campbell Ian G , Zhang Zoey Y , Grimm Kevin J
Published: March 2023

Study Objectives

Limiting spindle activity via sleep restriction could explain some of the negative cognitive effects of sleep loss in adolescents. The current study evaluates how sleep restriction affects sleep spindle number, incidence, amplitude, duration, and wave frequency and tests whether sleep restriction effects on spindles change across the years of adolescence. The study determines whether sleep restriction effects on daytime sleepiness, vigilance, and cognition are related to changes in sleep spindles.

Methods

In each year of this 3-year longitudinal study, 77 participants, ranging in age from 10 to 16 years, each completed three different time in bed (TIB) schedules: 7, 8.5, or 10 hours in bed for 4 consecutive nights. A computer algorithm detected and analyzed sleep spindles in night four central and frontal electroencephalogram. Objective and self-reported daytime sleepiness and cognition were evaluated on the day following the 4th night.

Results

For 7 versus 10 hours TIB average all-night frontal and central spindle counts were reduced by 35% and 32%, respectively. Reducing TIB also significantly decreased spindle incidence in the first 5 hours of non-rapid eye movement sleep, produced small but significant reductions in spindle amplitude, and had little to no effect on spindle duration and spindle wave frequency. Sleep restriction effects did not change with age. The reductions in spindle count and incidence were related to daytime sleepiness on the following day but were not related to working memory.

Conclusions

The sleep loss effects on daytime functioning in adolescents are partially mediated by reduced sleep spindles impacting daytime sleepiness.