bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparing the drivers of medical student emigration intention across two African nations
Authors: Chaet Alexis , Fessehaie Nathaniel , Rajaguru Praveen R. , Alavi Jusabani Mubashir , Randaoharison Pierana , Samison Luc , Anderson Ursula , Ramanantoanina Prisca , Zafimar Mosa , Numfor Anchi , Hardaker W. Mack , Massawe Honest , Pallangyo Anthony , Temu Rogers , Winterton Matthew , Sheth Neil P. 
Published: May 2021

AbstractBackgroundSub‐Saharan Africa faces the highest relative need for health care workers in the world and the emigration of physicians significantly contributes to this deficit. Few studies have explored development of these patterns during medical education. This study investigates career aspirations of medical students in two African nations with similar Human Development Indices, but distinct differences in training structure to better inform retention strategies.MethodsA cross‐sectional survey was administered in 2018 to medical students in Madagascar (University of Antananarivo, University of Mahajanga) and Tanzania (Kilimanjaro Christian Medical College, KCMC). Outcomes included emigration/career intentions, and factors influencing these decisions. Analysis utilised chi‐square and Fisher's exact tests (α < 0.05, two‐tailed) for statistical differences, logistic regression and qualitative content analysis of free text data.ResultsA total of 439 students responded to the survey with a response rate of 12.9% from Antananarivo (n = 142/1097), 11.6% from Mahajanga (n = 43/370), and 60.0% from KCMC (n = 254/423). Significantly more Malagasy (49.7%, n = 90/181) than Tanzanian (25.2%, n = 54/214) students expressed emigration intent (P < .001). Malagasy students indicating research, possibility of working abroad, or work intensity as influencing career choice more frequently expressed a desire to emigrate. Satisfaction with computer/internet access was inversely correlated with a desire to work abroad. In comparison, Tanzanian students reporting income potential as influential in their career choice or attending a private high school were more likely to express a desire to work abroad. Qualitative content analysis of free text data demonstrated deficits in faculty availability, diversity of training locations and a particular emphasis on infrastructure challenges within Madagascar.InterpretationA significant number of students desire to work abroad. Emigration interests are influenced by access to postgraduate training, infrastructure and opportunities in academia, which differ across countries. Efforts to retain physicians should consider these country and institution‐specific factors that influence medical student desire to emigrate.
Adding guidance to deliberate reflection improves medical student’s diagnostic accuracy
Authors: Fernandes Rachel Aparecida Ferreira , Malloy‐Diniz Leandro Fernandes , de Vasconcellos Marcos Carvalho , Camargos Paulo Augusto Moreira , Ibiapina Cássio 
Published: May 2021

AbstractContextDiagnostic competence in students is a major medical education goal. Adding instructional guidelines to prompt deliberate reflection fosters medical students’ diagnostic proficiency. This study investigates the effects of this teaching strategy on diagnostic accuracy in solving clinical cases of different complexity levels by novice and senior students.MethodEighty third‐year and 62 sixth‐year medical students participated in this three‐phase experimental study. First, participants were randomly assigned to one of three experimental conditions (free reflection, cued reflection and worked example) to diagnose 12 clinical text‐based cases, following different levels of deliberate reflection. In an immediate test and a delayed test, the participants diagnosed varied sets of 12 cases, six involving the same diseases (four routine and two rare). The main outcomes were the diagnostic accuracy scores achieved for the cases assessed by repeated measures of analysis of variance for each category.ResultsThere was a signiﬁcant primary effect of experimental condition (P < .001), year of training (P < .001) and study phase (P < .001) on the diagnostic accuracy achieved. The use of deliberate reflection in addition to instructional guidelines resulted in improved results in the immediate test for all cases evaluated (P < .001), regardless of participants’ seniority. In the delayed test, this benefit was maintained for simple cases (P < .001). For complex cases, the benefit was maintained only for senior students (P < .001). The cued reflection and worked example groups did not differ in performance (P > .05), but both groups surpassed the free reflection group (P < .001), regardless of the students' learning stage and case complexity.
Plant genera Cannabis and Humulus share the same pair of well‐differentiated sex chromosomes
Authors: Prentout Djivan , Stajner Natasa , Cerenak Andreja , Tricou Theo , Brochier‐Armanet Celine , Jakse Jernej , Käfer Jos , Marais Gabriel A. B. 
Published: May 2021

Summary

We recently described, in Cannabis sativa, the oldest sex chromosome system documented so far in plants (12–28 Myr old). Based on the estimated age, we predicted that it should be shared by its sister genus Humulus, which is known also to possess XY chromosomes.

Here, we used transcriptome sequencing of an F1 family of H. lupulus to identify and study the sex chromosomes in this species using the probabilistic method SEX‐DETector.

We identified 265 sex‐linked genes in H. lupulus, which preferentially mapped to the C. sativa X chromosome. Using phylogenies of sex‐linked genes, we showed that a region of the sex chromosomes had already stopped recombining in an ancestor of both species. Furthermore, as in C. sativa, Y‐linked gene expression reduction is correlated to the position on the X chromosome, and highly Y degenerated genes showed dosage compensation.

We report, for the first time in Angiosperms, a sex chromosome system that is shared by two different genera. Thus, recombination suppression started at least 21–25 Myr ago, and then (either gradually or step‐wise) spread to a large part of the sex chromosomes (c. 70%), leading to a degenerated Y chromosome.
A new P450 involved in the furanocoumarin pathway underlies a recent case of convergent evolution
Authors: Villard Cloé , Munakata Ryosuke , Kitajima Sakihito , van Velzen Robin , Schranz Michael Eric , Larbat Romain , Hehn Alain 
Published: May 2021

SummaryFuranocoumarins are phytoalexins often cited as an example to illustrate the arms race between plants and herbivorous insects. They are distributed in a limited number of phylogenetically distant plant lineages, but synthesized through a similar pathway, which raised the question of a unique or multiple emergence in higher plants.The furanocoumarin pathway was investigated in the fig tree (Ficus carica, Moraceae). Transcriptomic and metabolomic approaches led to the identification of CYP76F112, a cytochrome P450 catalyzing an original reaction. CYP76F112 emergence was inquired using phylogenetics combined within silicomodeling and site‐directed mutagenesis.CYP76F112 was found to convert demethylsuberosin into marmesin with a very high affinity. This atypical cyclization reaction represents a key step within the polyphenol biosynthesis pathway. CYP76F112 evolutionary patterns suggests that the marmesin synthase activity appeared recently in the Moraceae family, through a lineage‐specific expansion and diversification.The characterization of CYP76F112 as the first known marmesin synthase opens new prospects for the use of the furanocoumarin pathway. It also supports the multiple acquisition of furanocoumarin in angiosperms by convergent evolution, and opens new perspectives regarding the ability of cytochromes P450 to evolve new functions related to plant adaptation to their environment.
Electromagnetic interference from left ventricular assist device in patients with transvenous implantable cardioverter‐defibrillator
Authors: Khetarpal Banveet Kaur , Lee Justin Z. , Javaid Awad I. , Mi Lanyu , Venepally Nithin Rao , Narasimhan Bharat , Hardaway Brian W. , Cha Yong‐Mei , Kusumoto Fred , Mulpuru Siva K. , Srivathsan Komandoor 
Published: May 2021

AbstractBackgroundMany advanced heart failure patients have both a left ventricular assist device (LVAD) and an implantable cardioverter‐defibrillator (ICD). This study examines incidence, clinical impact, and management of LVAD‐related EMI.MethodsWe performed a three‐center retrospective analysis of transvenous ICD implanted patients with LVAD implanted between January 1, 2005 and December 31, 2020. The primary outcome was EMI after LVAD implantation, categorized as LVAD‐related noise or telemetry interference.ResultsThe rate of LVAD‐related EMI among the 737 patients (mean age 58.6 ± 12.8 years) studied was 5.0%. Telemetry interference (1.5%) compromised ICD interrogation in all patients. This was resolved successfully with use of a metal shield, encased wand, radiofrequency tower, different ICD programmer or by increasing distance between ICD programmer and LVAD (n = 6). ICD replacement was required to reestablish successful communication in three patients. LVAD‐related noise (3.5%) led to oversensing (n = 4), inappropriate mode switches (n = 4), noise reversion (n = 3), inhibition of pacing (n = 2), inappropriate detection as atrial fibrillation (AF) (n = 2) and inappropriate detection as ventricular tachycardia (VT) and/or ventricular fibrillation (VF) (n = 2). This noise interference persisted (n = 3), resolved spontaneously (n = 16), resolved with programming change (n = 6) or required lead revision (n = 1).ConclusionsEMI from LVAD impacts ICD function, although, the incidence rate is low. Physicians implanting both, LVAD in patients with ICD (more common) or ICD in patients with LVAD, should be aware of possible interferences. Telemetry failure not resolved by metal shielding was overcome by ICD generator replacement to a different manufacturer. In most cases, LVAD‐related noise resolves spontaneously.
Occurrence of two races of Puccinia kuehnii causing orange rust of sugarcane in Florida
Authors: Sanjel Santosh , Hincapie Martha , Wang Yunwen , Todd James , Chaulagain Bhim , Sood Sushma , Comstock Jack C. , Raid Richard N. , Rott Philippe 
Published: May 2021

AbstractOrange rust of sugarcane caused by Puccinia kuehnii was first reported in Florida in 2007. Since then, several sugarcane cultivars that were resistant during the initial epidemics became susceptible within a few years. These shifts in resistance were attributed to the evolution of the pathogen and appearance of new races. To study the variation in virulence of P. kuehnii, healthy leaf pieces of sugarcane cultivars susceptible to orange rust were brush inoculated with isolates of P. kuehnii collected from susceptible cultivars in the field. After inoculation, leaf pieces were placed in an incubator and disease severity based on the number of rust uredinia was determined 2 weeks postinoculation. Isolates of P. kuehnii collected from sugarcane cultivar CP 89‐2143, which only showed severe symptoms of orange rust starting in 2011–2012, produced 300%–500% more uredinia on CP 89‐2143 than the isolates collected from cultivar CL 85‐1040 that has been susceptible since 2007. Sugarcane cultivar CL 85‐1040 exhibited high and equivalent numbers of uredinia regardless of the inoculated isolate of the pathogen. These data support the occurrence of pathogenic specialization within P. kuehnii and the existence of at least two races of this pathogen in Florida. Analysis of amplified fragment‐length polymorphism among isolates of P. kuehnii from cultivars CP 89‐2143 and CL 85‐1040 differing in resistance to orange rust revealed genetic variation among rust uredinia. However, this variation was not associated with a specific sugarcane cultivar, suggesting that pathogenic variation was not linked to major, but rather to small genetic changes within the genome of P. kuehnii.
Larvae of longhorned beetles (Coleoptera; Cerambycidae) have evolved a diverse and phylogenetically conserved array of plant cell wall degrading enzymes
Authors: Shin Na Ra , Shin Seunggwan , Okamura Yu , Kirsch Roy , Lombard Vincent , Svacha Petr , Denux Olivier , Augustin Sylvie , Henrissat Bernard , McKenna Duane D. , Pauchet Yannick 
Published: May 2021

AbstractLonghorned beetles (Cerambycidae) are the most diverse group of predominantly wood‐feeding (xylophagous) insects on Earth. Larvae of most species feed within tissues of plants made up of large amounts of plant cell wall (PCW), which is notoriously difficult to digest. To efficiently access nutrients from their food source, cerambycid larvae have to deconstruct PCW polysaccharides – such as cellulose, hemicelluloses and pectin – requiring them to possess a diversity of plant cell wall degrading enzymes (PCWDEs) in their digestive tract. Genomic data for Cerambycidae are mostly limited to notorious forest pests and are lacking for most of the taxonomic groups. Consequently, our understanding of the distribution and evolution of cerambycid PCWDEs is quite limited. We addressed the numbers, kinds and evolution of cerambycid PCWDEs by surveying larval midgut transcriptomes from 23 species representing six of the eight recognized subfamilies of Cerambycidae and each with very diverse host types (i.e., gymnosperms, angiosperms, xylem, phloem, fresh or dead plant tissues). Using these data, we identified 340 new putative PCWDEs belonging to ten carbohydrate active enzyme families, including two gene families (GH7 and GH53) not previously reported from insects. The remarkably wide range of PCWDEs expressed by Cerambycidae should allow them to break down most PCW polysaccharides. Moreover, the observed distribution of PCWDEs encoded in cerambycid genomes agreed more with phylogenetic relationship of the species studied than with the taxonomic origin or quality of the host plant tissues.
High dose valaciclovir to prevent cytomegalovirus infection in allogeneic haematopoietic stem cell transplant recipients
Authors: Lam Stephanie , Boan Peter , Polistena Paola , Cannell Paul , Cooney Julian , Wright Matthew , Purtill Duncan 
Published: May 2021

AbstractCytomegalovirus (CMV) infection causes morbidity and mortality after allogeneic haematopoietic stem cell transplantation (HSCT). We investigated whether prophylaxis with high dose valaciclovir is effective at reducing the incidence of clinically significant CMV infection (csCMVi) within six months of allogeneic HSCT.Consecutive allogeneic HSCT recipients who received 2g valaciclovir orally four times daily from transplant until day 100 (prophylaxis group) were compared to subsequent patients who received no CMV prophylaxis (control group).Forty‐nine patients in the prophylaxis group and 59 in the control group were included. The cumulative incidence of csCMVi at 6 months was 20% (95% confidence interval (CI): 9%‐27%) in the prophylaxis group and 39% (95% CI: 26%‐47%) in the control group (P = .009). There was no CMV disease in the prophylaxis group and three cases in the control group. There was no difference in time to neutrophil or platelet recovery nor graft failure between groups. On multivariable analysis, lack of high dose valaciclovir prophylaxis, positive recipient CMV IgG and age were associated with greater likelihood of csCMVi. There was no significant difference in acute graft versus host disease, non‐relapse mortality or overall survival between groups.In this retrospective cohort study, high dose valaciclovir prophylaxis resulted in a lower incidence of csCMVi within six months of HSCT.
Nuclear transport factor GmNTF2B‐1 enhances soybean drought tolerance by interacting with oxidoreductase GmOXR17 to reduce reactive oxygen species content
Authors: Chen Kai , Su Chen , Tang Wensi , Zhou Yongbin , Xu Zhaoshi , Chen Jun , Li Haiyan , Chen Ming , Ma Youzhi 
Published: May 2021

SUMMARYDrought is a critical abiotic stressor that modulates soybean yield. Drought stress drastically enhances reactive oxygen species (ROS) formation, and maintaining ROS content above a cytostatic level but below a cytotoxic level is essential for normal biology processes in plants. At present, most of the known ROS‐scavenging systems are in the cytoplasm, and the mechanism of ROS regulation in the nucleus remains unclear. GmNTF2B‐1 is a member of the IV subgroup in the nucleus transporter family. Its expression is localized to the roots and is stimulated by drought stress. In this study, the overexpression of GmNTF2B‐1 was found to improve the drought tolerance of transgenic soybean by influencing the ROS content in plants. An oxidoreductase, GmOXR17, was identified to interact with GmNTF2B‐1 in the nucleus through the yeast two‐hybrid, coimmunoprecipitation and bimolecular fluorescence complementation assays. The drought tolerance of GmOXR17 transgenic soybean was similar to that of GmNTF2B‐1. GmNTF2B‐1 was expressed in both cytoplasm and nucleus, and GmOXR17 transferred from the cytoplasm to the nucleus under drought stress. The overexpression of GmNTF2B‐1 enhanced the nuclear entry of GmOXR17, and the overexpression of GmNTF2B‐1 or GmOXR17 could decrease the H2O2 content and oxidation level in the nucleus. In conclusion, the interaction between GmNTF2B‐1 and GmOXR17 may enhance the nuclear entry of GmOXR17, thereby enhancing nuclear ROS scavenging to improve the drought resistance of soybean.
Theoretical Leakage Equations Towards Liquid-Phase Flow in the Straight-Through Labyrinth Seal
Authors: Han Lingsheng , Wang Yongqing , Liu Kuo , Ban Ziyou , Qin Bo , Liu Haibo , Dai Minghua 
Published: May 2021

AbstractLabyrinth seals are widely applied in turbomachinery for gas and liquid sealing. A series of labyrinth seal leakage equations so far have been proposed for compressible gas and few equations for incompressible liquid. Based on the flow conserving governing equations, this paper originally presents semi-empirical analytic equations of the leakage flow rate and tooth-clearance pressure for liquid-phase flow in the straight-through labyrinth seal. The equations indicate that the leakage and pressure are closely related to the inlet pressure, outlet pressure, seal geometrical parameters, and four empirical coefficients, while no relation to the temperature and compressibility effects compared to the common gas equations. The empirical coefficients include the velocity compensation coefficient, friction coefficient, jet contraction coefficient, and resistance coefficient. Particularly, the velocity compensation coefficient is determined through an optimization by the genetic algorithm, while others are referred from previous research. Ultimately, taking the sealing of deeply subcooled liquid nitrogen within the spindle of the cryogenic cooling machine tool as a case, the accuracy of proposed equations is evaluated under various pressure ratios and geometry conditions using the numerical approach, whose numerical model has been validated by the experimental data in the literature. The results show that errors between calculation and simulation are generally within the limit of ±5%, except for the pressure values at the first two teeth. This work provides a theoretical basis for further studies on the liquid leakage equations in other labyrinth seal types.
Experimental Study on the Coefficient of Friction of the Ball Screw
Authors: Zhang Lu-Chao , Zhou Chang-Guang 
Published: May 2021

Abstract
The coefficient of friction (COF) is a key factor to estimate the performance of ball screws. Pieces of research focus on the experimental study of the COF, leading to the COF chosen empirically in many studies. To acquire the COF of the ball screw, a measuring system is conducted to detect the friction torque under different preloads and rotational speeds and the effects of the applied axial load and rotational speed on the COF are analyzed. By the curve fitting method, the Stribeck curve of the ball screw is obtained. The experimental results show that the lubricating state can be divided into two categories: the mixed lubrication state and the elastohydrodynamic lubrication state. This study is beneficial to choose a suitable working condition for a different performance of the ball screw.
Finite-State Automata-Based Representation of Device States for Function Modeling of Multimodal Devices
Authors: Chowdhury Ahmed , Venkatanarasimhan Lakshmi N.A. , Sen Chiradeep 
Published: May 2021

Abstract
Graph-based function models used in early-stage systems design usually represent only one operational mode of the system. Currently, there is a need, but no rigorous formalism to model multiple possible modes in the model and logically predict the behavior of the system as it transitions between the modes. This paper presents a representation of operational modes and states of technical devices and systems based on automata theory for both discrete and continuous state transitions. It then presents formal definitions of three signal-processing verbs that actuate or regulate energy flows: Actuate_E, Regulate_E_Discrete, and Regulate_E_Continuous. The graphical templates, definitions, and application of each verb in modeling are illustrated. Finally, a system-level model is used to illustrate the verbs’ modeling and reasoning ability, in terms of cause-and-effect propagation and the systems’ transition between operational modes.
Immediate temperature response in northern Iberia to last deglacial changes in the North Atlantic
Authors: Bernal-Wormull J.L. , Moreno A. , Pérez-Mejías C. , Bartolomé M. , Aranburu A. , Arriolabengoa M. , Iriarte E. , Cacho I. , Spötl C. , Edwards R.L. , Cheng H. 
Published: May 2021

AbstractMajor disruptions in the North Atlantic circulation during the last deglaciation triggered a series of climate feedbacks that influenced the course of Termination I, suggesting an almost synchronous response in the ocean-atmosphere system. We present a replicated δ18O stalagmite record from Ostolo cave in the northern Iberian Peninsula with a robust chronological framework that continuously covers the last deglaciation (18.5–10.5 kyr B.P.). The Ostolo δ18O record, unlike other speleothem records in the region that were related to humidity changes, closely tracks the well-known high-latitude temperature evolution, offering important insights into the structure of the last deglaciation in the Northern Hemisphere. In addition, this new record is accompanied by a clear signal of the expected cooling events associated with the deglacial disruptions in North Atlantic deep convection during Heinrich event 1.
Widespread glacial erosion on the Scandinavian passive margin
Authors: Pedersen Vivi K. , Knutsen Åsne Rosseland , Pallisgaard-Olesen Gustav , Andersen Jane Lund , Moucha Robert , Huismans Ritske S. 
Published: May 2021

AbstractThe topography in Scandinavia features enigmatic high-elevation low-relief plateau regions dissected by deep valleys and fjords. These plateau regions have long been interpreted as relict landforms of a preglacial origin, whereas recent studies suggest they have been modified significantly by glacial and periglacial denudation. We used late Pliocene–Quaternary source-to-sink analyses to untangle this scientific conundrum. We compared glacier-derived offshore sediment volumes with estimates of erosion in onshore valleys and fjords and on the inner shelf. Our results suggest that onshore valley and fjord erosion falls 61%–66% short of the offshore sink volume. Erosion on the inner shelf cannot accommodate this mismatch, implying that the entire Scandinavian landscape and adjacent shelf have experienced significant glacial erosion.