bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional contribution of two perennial grasses to enhance pasture production and drought resistance under a leaf regrowth stage defoliation criterion
Authors: García‐Favre Javier , López Ignacio F. , Cranston Lydia M. , Donaghy Daniel J. , Kemp Peter D. , Ordóñez Iván P.
Published: May 2022

Lolium perenne L. (Lp) is the main pasture species in New Zealand, but climate change increases the likelihood of drought during summer and consequently lowers its growth rates. Bromus valdivianus Phil. (Bv) tolerates better the summer soil water restriction, but its competitiveness in a diverse pasture relates to the defoliation management and soil moisture levels. The performance of both species in terms of production, persistence and feed quality across seasons under different defoliation regimens was evaluated when the species were mixed and in monoculture. The treatments were applied in a randomised complete block design with three blocks. Bromus valdivianus and Lp monocultures and the 50/50 mixture (Mx) were grazed at low and high defoliation frequencies (i.e. based on Bv and Lp optimal leaf regrowth stage [LS], respectively). Herbage mass production was 15% higher in the Mx, mainly due to an increase in production in spring and summer. In spring, there was complementarity growth between the species, while during summer/early autumn, the Mx production relayed in the higher participation of Bv. Root biomass at depth (31–70 cm) was 38% greater for Bv monoculture and the Mx compared with Lp monoculture, which demonstrated the contribution of Bv to a better production of the mixture during and following the dry periods. In addition, the maintenance of the Bv tiller population and the higher growth rate during dry periods demonstrated its better fitness to low soil water availabilities than Lp. Although herbage mass was not modified by the defoliation frequency, forage quality of Bv showed values at low defoliation frequency that could compromise animal production during spring. However, there was an increase in root biomass under low defoliation frequencies, which suggested that a flexible grazing management across seasons would increase the niche utilisation between species in the mixture. The defoliation frequency of the mixture could be based on Lp LS during spring and winter, and slowed down, following Bv criteria, during summer and autumn.
Does attachment anxiety accentuate the effect of perceived contract breach on counterproductive work behaviors?
Authors: Jahanzeb Sadia , Bouckenooghe Dave , Baig Muhammad Usman Anwar
Published: May 2022

Applying belongingness and attachment theories, we explore the association between employees' perception of psychological contract breach and counterproductive work behaviors, while also considering the mediating effect of workplace ostracism and the moderating role of attachment styles (i.e., attachment anxiety and attachment avoidance). Time‐lagged data from full‐time personnel working in telecommunications and transportation sectors in North America were collected at three different time points with an interval of 3 weeks between each wave. A total of 272 responses from the three measurement points were retained for our analysis. In support of what was hypothesized, our study's findings show that perception of contract breach fueled workplace deviance through the anticipated effect of workplace ostracism. Furthermore, and in line with what we assumed, the mediating effect of workplace ostracism was reinforced by employees' fear of rejection and abandonment in relationships (i.e., attachment anxiety). The role of attachment avoidance, however, was not found to moderate the indirect effect, contrary to our expectations. In conclusion, embedded in belongingness and attachment theorizing, this study offers empirical evidence of how workplace ostracism is a crucial mechanism that helps to explain the indirect effect through which psychological contract breach triggers counterproductive work behaviors. Furthermore, our findings illustrate how this relationship is conditional on attachment anxiety observed in employees.
Recent advances onDNAand omics‐based technology in Food testing and authentication: A review
Authors: Kumar Pramod , Rani Alka , Singh Shalini , Kumar Anuj
Published: May 2022

The authentication of food is an urgent concern owing to the increasing population and direct consequences of food on public health. Food authentication using DNA and omics‐based methods is gaining ground due to critical advantages notably in the areas of food adulteration in plant and animal‐based food and feed products and in determining the quality of food and food spoilage. Besides, there is greater demand for the detection of genetically modified foods (GMOs) and the detection of allergens, toxins, and carcinogens like tobacco in the food. The present review summarizes the advanced DNA and omics‐based methods (genomics, metabolomics, and proteomics) in the food industry. DNA‐based methods rely on specific markers known as reference genes for food authentication. Lactic acid bacteria such asStreptococcus thermophilesare being used as probiotics for treating infectious diseases and as an essential culture in the fermentation industry. Novel methods like CRISPR‐Cas have been recently introduced for the management of beneficial micro‐organisms relevant to food like probiotics and starter cultures by enhancing their production and restraining damaging pathogens. These methods can detect the source, presence of allergens, adulteration, and mislabeling in food products.
Pathways to polar adaptation in fishes revealed by long‐read sequencing
Authors: Hotaling Scott , Desvignes Thomas , Sproul John S. , Lins Luana S. F. , Kelley Joanna L.
Published: May 2022

Long‐read sequencing is driving a new reality for genome science in which highly contiguous assemblies can be produced efficiently with modest resources. Genome assemblies from long‐read sequences are particularly exciting for understanding the evolution of complex genomic regions that are often difficult to assemble. In this study, we utilized long‐read sequencing data to generate a high‐quality genome assembly for an Antarctic eelpout, Ophthalmolycus amberensis, the first for the globally distributed family Zoarcidae. We used this assembly to understand how O. amberensis has adapted to the harsh Southern Ocean and compared it to another group of Antarctic fishes: the notothenioids. We showed that selection has largely acted on different targets in eelpouts relative to notothenioids. However, we did find some overlap; in both groups, genes involved in membrane structure, thermal tolerance and vision have evidence of positive selection. We found evidence for historical shifts of transposable element activity in O. amberensis and other polar fishes, perhaps reflecting a response to environmental change. We were specifically interested in the evolution of two complex genomic loci known to underlie key adaptations to polar seas: haemoglobin and antifreeze proteins (AFPs). We observed unique evolution of the haemoglobin MN cluster in eelpouts and related fishes in the suborder Zoarcoidei relative to other Perciformes. For AFPs, we identified the first species in the suborder with no evidence of afpIII sequences (Cebidichthys violaceus) in the genomic region where they are found in all other Zoarcoidei, potentially reflecting a lineage‐specific loss of this cluster. Beyond polar fishes, our results highlight the power of long‐read sequencing to understand genome evolution.
On the large‐scale production of a new vaccine
Authors: Angelus Alexandar , Özer Özalp
Published: May 2022

Large‐scale production of a new vaccine, such as the COVID‐19 vaccine, is characterized by evolving demand and production yield uncertainties. Further, following its FDA approval for efficacy and safety, a vaccine may not even be manufacturable due to its low production yield and the resulting lack of profitability. To deal with those challenges in practice, a vaccine manufacturer can (stochastically) increase the uncertain yield of a vaccine prior to launching large‐scale production by learning through small‐scale, experimental production runs about manufacturing conditions that are conducive to raising that yield. After starting large‐scale production and receiving revenues from the sale of the vaccine, the manufacturer can continue to stochastically improve vaccine yield by acquiring knowledge from real‐time production data. The two key decisions faced by a vaccine manufacturer concern the optimal timing and capacity of the vaccine's large‐scale production. To determine the structure of vaccine manufacturer's optimal decisions, we formulate and solve a stochastic, multiperiod, sequential‐decision model, while incorporating the dynamic evolution of vaccine yield uncertainty under those two yield improvement strategies. We establish the optimality of a threshold stopping policy for the timing of the large‐scale vaccine production. This policy depends in a fundamental way on the relative stochastic rates of the two yield improvement strategies. We characterize the manufacturer's optimal capacity decision and identify conditions under which optimal capacity and production yield become substitutes. We analyze the implications of our results for rendering a new vaccine large‐scale manufacturable, and bringing it to the market sooner during a pandemic period.
When do group incentives for retail store managers work?
Authors: Lee Hyun Seok (Huck) , Kesavan Saravanan , Kuhnen Camelia
Published: May 2022

Retail stores are geographically dispersed as a part of a multiunit organization. In such a setting, store managers play an important role in driving store performance. To motivate them to exert effort, retailers have provided group incentives for store managers. Using data from 75 stores of a U.S.‐based retail chain that changed its incentive plan for store managers from being purely dependent on store performance to being dependent upon both store and corporate performance, we investigate the effect of this change on store performance. We also examine the moderating role of geographical proximity among stores and past performance of the focal store. To establish a causality, we identify a control group from a matched store of another retail chain in the same industry and perform a difference‐in‐differences analysis. We find that making managers' bonus dependent on corporate goals has resulted in overall worsening of store performance. However, such an effect is contingent upon both geographical proximity among stores and past performance of the focal store. The impact of the incentive change on store performance is positively moderated by the increase in stores within close geographical proximity, while it is negatively moderated by the past performance of the focal store. This paper broadens our understanding of how incentives work in practice, and more importantly, documents how firms can design more effective incentive schemes for managers by considering relevant conditions, such as stores' geographical networks and their past performance.
Approximation schemes for the joint inventory selection and online resource allocation problem
Authors: Chen Xingxing , Feldman Jacob , Jung Seung Hwan , Kouvelis Panos
Published: May 2022

In this paper, we introduce and study the joint inventory selection and online resource allocation problem, which is characterized by two sequential sets of decisions that are irrevocably linked. First, a decision maker (DM) must select starting inventory levels for a set of available resources. Subsequently, the DM must match arriving customers to available resources in an online fashion so as to maximize expected reward. We first study the problem in its most general form, before focusing on a specific version that arises at Anheuser Busch InBev (ABI). This particular application of our general setting is referred to as the ABI Trailer Problem, and it considers how ABI ships its beer to vendors via third‐party delivery trucks. In this problem, ABI must select the weights of preloaded trailers of beer, which are then matched in an online fashion to the arriving third‐party delivery trucks. For the general setting, we develop simple and easy‐to‐implement approaches that come with robust worst‐case performance guarantees. For the ABI setting, we reveal a simplifying structural property related to the optimal matching policy, which gives rise to a natural adaptation of our original approach. We test the efficacy of these policies through extensive numerical experiments, where we find that our approaches are either near‐optimal or improve upon state‐of‐the‐art benchmarks. In particular, using a data set from ABI, we are able to generate instances of the ABI Trailer Problem, on which our algorithm has the potential to yield revenue improvements in the range of millions of dollars per year.
Widening double dualisation? Labour market inequalities and national social policy responses in Western Europe during the first wave of the COVID‐19 pandemic
Authors: Natili Marcello , Negri Fedra , Ronchi Stefano
Published: May 2022

Europe is witnessing a ‘double dualisation’ process, whereby inequalities have increased both between labour market insiders and outsiders, and between core and peripheral countries. We test the double dualisation hypothesis in the context of the first wave of the COVID‐19 pandemic. Did the COVID crisis exacerbate income inequalities between insiders and outsiders? Did cross‐country territorial divides also increase? Did national governments' emergency measures contribute to containing or widening double dualisation? We deploy a multi‐method research design that combines original survey data on seven old EU member states with three case studies on Germany, Italy, and the Netherlands. Results show that, in the short term, the COVID‐19 pandemic has been a catalyst of double dualisation: outsiders bore the greatest burden, especially in southern European countries. National emergency measures largely depended on the fiscal leeway available to governments and followed pre‐existing welfare trajectories, thus worsening cross‐country inequalities, with potentially severe consequences for the European integration process.
Increased contribution of KCa channels to muscle contraction induced vascular and blood flow responses in sedentary and exercise trained ZFDM rats
Authors: Sonobe Takashi , Tsuchimochi Hirotsugu , Maeda Hisashi , Pearson James T.
Published: May 2022

In resistance arteries, endothelium‐dependent hyperpolarization (EDH)‐mediated vasodilatation is depressed in diabetes. We hypothesized that downregulation of KCa channel derived EDH reduces exercise‐induced vasodilatation and blood flow redistribution in diabetes. To test this hypothesis, we evaluated vascular function in response to hindlimb muscle contraction, and the contribution of KCa channels in anaesthetised ZFDM, metabolic disease rats with type 2 diabetes. We also tested whether exercise training ameliorated the vascular response. Using in vivo microangiography, the hindlimb vasculature was visualized before and after rhythmic muscle contraction (0.5 s tetanus every 3 s, 20 times) evoked by sciatic nerve stimulation (40 Hz). Femoral blood flow of the contracting hindlimb was simultaneously measured by an ultrasonic flowmeter. The contribution of KCa channels was investigated in the presence and absence of apamin and charybdotoxin. We found that vascular and blood flow responses to muscle contraction were significantly impaired at the level of small artery segments in ZFDM fa/fa rats compared to its lean control fa/+ rats. The contribution of KCa channels was also smaller in fa/fa than in fa/+ rats. Low‐intensity exercise training for 12 weeks in fa/fa rats demonstrated minor changes in the vascular and blood flow response to muscle contraction. However, the KCa‐derived component in the response to muscle contraction was much greater in exercise trained than in sedentary fa/fa rats. These data suggest that exercise training increases the contribution of KCa channels among endothelium‐dependent vasodilatory mechanisms to maintain vascular and blood flow responses to muscle contraction in this metabolic disease rat model.

Key points

Microvascular dysfunction in type 2 diabetes impairs blood flow redistribution during exercise and limits the performance of skeletal muscle and may cause early fatigability.

Endothelium‐dependent hyperpolarization (EDH), which mediates vasodilatation in resistance arteries, is known to be depressed in animals with diabetes.

Here, we report that low‐intensity exercise training in ZFDM rats increased the KCa channel‐derived component in the vasodilator responses to muscle contraction compared to that in sedentary rats, partly as a result of the increase in KCNN3 expression.

These results suggest that low‐intensity exercise training improves blood flow redistribution in contracting skeletal muscle in metabolic disease with diabetes via upregulation of EDH.
Redes sociales virtuales y estrategias de afrontamiento en migrantes de Colombia, Panamá y Chile: Diferencias y relaciones
Authors: Layne Bernal Benilda , Cardona Isaza Arcadio Jesús , Alvarez Massi Pedro Ángel
Published: May 2022

Las redes sociales virtuales son un medio importante en las relaciones interpersonales de los migrantes en el país de origen y de destino. El objetivo de este estudio fue analizar las relaciones y diferencias en el uso de las redes sociales virtuales y las estrategias de afrontamiento en migrantes de diferentes países que viven en Colombia, Chile y Panamá. Se trata de un estudio transversal correlacional y comparativo. Participaron 125 migrantes (M = 30.63, DE = 9.79); 55.2 % eran mujeres. Se evaluaron las estrategias de afrontamiento y el uso de las redes sociales. Se realizaron análisis descriptivos y correlacionales. También se compararon las variables por países. Los resultados indican una relación entre las redes sociales virtuales y las estrategias de afrontamiento, así como diferencias en las estrategias de afrontamiento entre los migrantes de cada país, principalmente en la reevaluación positiva, la búsqueda de apoyo social y la evitación. Se concluye que las redes sociales virtuales son un medio que puede contribuir a la comunicación, la adaptación y el apoyo social. Sin embargo, se observa que las redes sociales virtuales también pueden ser utilizadas para la discriminación y la xenofobia.
Linear viscoelasticity of PP/PS/MWCNT composites with co-continuous morphology
Authors: Strugova Daria , David Éric , Demarquette Nicole R.
Published: May 2022

In this work, a study of the linear viscoelastic properties of co-continuous polypropylene/polystyrene blends filled with multiwall carbon nanotubes (MWCNTs) is presented. The YZZ rheological model [W. Yu et al., Polymer 51, 2091–2098 (2010)] is employed to correlate the rheological behavior of the blends with their microstructure and electrical properties. A test design involving a sequence of small amplitude oscillatory shear and a time sweep (simulating thermal annealing) is used to evaluate the morphology and evolution of electrical properties. It was shown that the YZZ rheological model could be successfully modified to be able to quantify a co-continuous morphology of filled composites. The calculated characteristic domain size was found to be in good agreement with the experimental data obtained via scanning electron microscopy. Furthermore, it is shown that the characteristic domain size slightly decreased after 30 min of thermal annealing. It was shown, as well, that thermal annealing promoted a reduction in the electrical percolation threshold (wt. % MWCNT) from 0.28 to 0.06.
Saving the Life of a National Sport Organization With Strategy and Governance
Authors: Parent Milena M.
Published: May 2022

Endurance Canada is facing a dire situation. It must turn itself around or face bankruptcy. The problems are piling up for Endurance Canada’s Board of Directors. Over the last 20 years, the Board’s Chair, Bill Fitzpatrick, has seen his sport’s athletes go from winning Olympic medals to not having any medals internationally. Within Endurance Canada, he has seen high staff turnover and burnout, power struggles between the national and provincial/territorial levels, and their revenues have been hit hard. COVID-19 was the proverbial nail in the coffin. Something drastic needs to happen. So, Bill brings in Amanda Tsang, a strategy expert. She has 1 month to come up with a plan to bring Endurance Canada back to life. The case follows Amanda as she reviews the strategy, structure, and governance issues in the organization. This fictional case asks students to (a) develop a strategic plan for Endurance Canada, (b) show how structure and strategy are interrelated, and (c) reflect on governance issues in a multilevel governance system.
Daily Outdoor Cycling by Older Adults Preserves Reactive Balance Behavior: A Case-Control Study
Authors: Batcir Shani , Melzer Itshak
Published: May 2022

We examined whether older adults who cycle outdoors regularly have better reactive balance control than noncycling older adults. Sixteen cyclist older adults and 24 age-, sex-, and health-matched controls who did not cycle (noncyclists) were exposed to unannounced perturbations of increased magnitudes in standing. We evaluated the strategies and kinematics employed at each perturbation magnitude. We found that cyclists exhibited a significantly higher stepping threshold, lower probability of stepping at each perturbation magnitude, and lower number of trials in which the participant needed to make a step to retain their balance. Cyclists also tended to recover balance using unloaded leg strategies in the first recovery step rather than a loaded leg strategy; they showed faster swing phase duration in the first recovery step, better controlling the displacement of center of mass than noncyclists. Older adults who cycle regularly outdoors preserve their reactive balance functions, which may reduce fall risks.
Validation of Body-Worn Sensors for Gait Analysis During a 2-min Walk Test in Children
Authors: Shieh Vincent , Zampieri Cris , Sansare Ashwini , Collins John , Bulea Thomas C. , Jain Minal
Published: May 2022

Introduction: Instrumented gait mat systems have been regarded as one of the gold standard methods for measuring spatiotemporal gait parameters. However, their portable walkways confine walking to a restricted area and limit the number of gait cycles collected. Wearable inertial sensors are a potential alternative that allow more natural walking behavior and have fewer space restrictions. The objective of this pilot study was to establish the concurrent validity of body-worn sensors against the portable walkway system in older children. Methods: Twenty-one participants (10 males) 7–17 years old performed 2-min walk tests at a self-selected and fast pace in a 25-m-long hallway, while wearing three inertial sensors. Data collection were synchronized between devices and the portions of the walk when subjects passed on the walkway were used to compare gait speed, stride length, gait cycle duration, cadence, and double support time. Regression models and Bland–Altman analysis were completed to determine agreement between systems for the selected gait parameters. Results: Gait speed, cadence, gait cycle duration, and stride length as measured by inertial sensors demonstrated strong agreement overall. Double support time was found to have lower validity due to a combined bias of age, height, weight, and walking pace. Conclusion: These results support the validity of wearable inertial sensors in measuring gait speed, cadence, gait cycle duration, and stride length in children 7 years old and above during a 2-min walking test. Future studies are warranted with a broader age range to thoroughly represent the pediatric population.
Two-step diffusion in cellular hygroscopic (vascular plant-like) materials
Authors: Cocusse Marion , Rosales Matteo , Maillet Benjamin , Sidi-Boulenouar Rahima , Julien Elisa , Caré Sabine , Coussot Philippe
Published: May 2022

Vascular plants, a vast group including conifers, flowering plants, etc., are made of a cellular hygroscopic structure containing water in the form of either free (i.e., in a standard liquid state) or bound (i.e., absorbed in the cell walls) water. From nuclear magnetic resonance techniques, we distinguish the dynamics of bound water and free water in a typical material (softwood) with such a structure, under convective drying. We show that water extraction relies on two mechanisms of diffusion in two contiguous regions of the sample, in which respectively the material still contains free water or only contains bound water. However, in any case, the transport is ensured by bound water. This makes it possible to prolong free water storage despite dry external conditions and shows that it is possible to extract free water in depth (or from large heights) without continuity of the free water network.
Developmental dynamics of the neural crest–mesenchymal axis in creating the thymic microenvironment
Authors: Handel Adam E. , Cheuk Stanley , Dhalla Fatima , Maio Stefano , Hübscher Tania , Rota Ioanna , Deadman Mary E. , Ekwall Olov , Lütolf Matthias , Weinberg Kenneth , Holländer Georg
Published: May 2022

The thymic stroma is composed of epithelial and nonepithelial cells providing separate microenvironments controlling homing, differentiation, and selection of hematopoietic precursor cells to functional T cells. Here, we explore at single-cell resolution the complex composition and dynamic changes of the nonepithelial stromal compartment across different developmental stages in the human and mouse thymus, and in an experimental model of the DiGeorge syndrome, the most common form of human thymic hypoplasia. The detected gene expression signatures identify previously unknown stromal subtypes and relate their individual molecular profiles to separate differentiation trajectories and functions, revealing an unprecedented heterogeneity of different cell types that emerge at discrete developmental stages and vary in their expression of key regulatory signaling circuits and extracellular matrix components. Together, these findings highlight the dynamic complexity of the nonepithelial thymus stroma and link this to separate instructive roles essential for normal thymus organogenesis and tissue maintenance.
Intracellular silicification by early-branching magnetotactic bacteria
Authors: Li Jinhua , Liu Peiyu , Menguy Nicolas , Zhang Xingliang , Wang Jian , Benzerara Karim , Feng Lianjun , Sun Lei , Zheng Yue , Meng Fanqi , Gu Lin , Leroy Eric , Hao Jialong , Chu Xuelei , Pan Yongxin
Published: May 2022

Biosilicification—the formation of biological structures composed of silica—has a wide distribution among eukaryotes; it plays a major role in global biogeochemical cycles, and has driven the decline of dissolved silicon in the oceans through geological time. While it has long been thought that eukaryotes are the only organisms appreciably affecting the biogeochemical cycling of Si, the recent discoveries of silica transporter genes and marked silicon accumulation in bacteria suggest that prokaryotes may play an underappreciated role in the Si cycle, particularly in ancient times. Here, we report a previously unidentified magnetotactic bacterium that forms intracellular, amorphous silica globules. This bacterium, phylogenetically affiliated with the phylum Nitrospirota, belongs to a deep-branching group of magnetotactic bacteria that also forms intracellular magnetite magnetosomes and sulfur inclusions. This contribution reveals intracellularly controlled silicification within prokaryotes and suggests a previously unrecognized influence on the biogeochemical Si cycle that was operational during early Earth history.
Detecting anti–SARS-CoV-2 antibodies in urine samples: A noninvasive and sensitive way to assay COVID-19 immune conversion
Authors: Ludolf Fernanda , Ramos Fernanda F. , Bagno Flávia F. , Oliveira-da-Silva João A. , Reis Thiago A. R. , Christodoulides Myron , Vassallo Paula F. , Ravetti Cecilia G. , Nobre Vandack , da Fonseca Flavio G. , Coelho Eduardo A. F.
Published: May 2022

Serum-based ELISA (enzyme-linked immunosorbent assay) has been widely used to detect anti–severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies. However, to date, no study has investigated patient urine as a biological sample to detect SARS-CoV-2 virus-specific antibodies. An in-house urine-based ELISA was developed using recombinant SARS-CoV-2 nucleocapsid protein. The presence of SARS-CoV-2 antibodies in urine was established, with 94% sensitivity and 100% specificity for the detection of anti–SARS-CoV-2 antibodies with the urine-based ELISA and 88% sensitivity and 100% specificity with a paired serum-based ELISA. The urine-based ELISA that detects anti–SARS-CoV-2 antibodies is a noninvasive method with potential application as a facile COVID-19 immunodiagnostic platform, which can be used to report the extent of exposure at the population level and/or to assess the risk of infection at the individual level.
Directionality of PYD filament growth determined by the transition of NLRP3 nucleation seeds to ASC elongation
Authors: Hochheiser Inga V. , Behrmann Heide , Hagelueken Gregor , Rodríguez-Alcázar Juan F. , Kopp Anja , Latz Eicke , Behrmann Elmar , Geyer Matthias
Published: May 2022

Inflammasomes sense intrinsic and extrinsic danger signals to trigger inflammatory responses and pyroptotic cell death. Homotypic pyrin domain (PYD) interactions of inflammasome forming nucleotide-binding oligomerization domain (NOD)–like receptors with the adaptor protein ASC (apoptosis-associated speck-like protein containing a CARD) mediate oligomerization into filamentous assemblies. We describe the cryo–electron microscopy (cryo-EM) structure of the human NLRP3
PYD
filament and identify a pattern of highly polar interface residues that form the homomeric interactions leading to characteristic filament ends designated as A- and B-ends. Coupling a titration polymerization assay to cryo-EM, we demonstrate that ASC adaptor protein elongation on NLRP3
PYD
nucleation seeds is unidirectional, associating exclusively to the B-end of the filament. Notably, NLRP3 and ASC PYD filaments exhibit the same symmetry in rotation and axial rise per subunit, allowing a continuous transition between NLRP3 and ASC. Integrating the directionality of filament growth, we present a molecular model of the ASC speck consisting of active NLRP3, ASC, and Caspase-1 proteins.
Modular super-assembly of hierarchical superstructures from monomicelle building blocks
Authors: Zhao Zaiwang , Zhao Yujuan , Lin Runfeng , Ma Yuzhu , Wang Lipeng , Liu Liangliang , Lan Kun , Zhang Jie , Chen Hanxing , Liu Mengli , Bu Fanxing , Zhang Pengfei , Peng Liang , Zhang Xingmiao , Liu Yupu , Hung Chin-Te , Dong Angang , Li Wei , Zhao Dongyuan
Published: May 2022

Manipulating the super-assembly of polymeric building blocks still remains a great challenge due to their thermodynamic instability. Here, we report on a type of three-dimensional hierarchical core-satellite SiO
2
@monomicelle spherical superstructures via a previously unexplored monomicelle interfacial super-assembly route. Notably, in this superstructure, an ultrathin single layer of monomicelle subunits (~18 nm) appears in a typically hexagon-like regular discontinuous distribution (adjacent micelle distance of ~30 nm) on solid spherical interfaces (SiO
2
), which is difficult to achieve by conventional super-assembled methods. Besides, the number of the monomicelles on colloidal SiO
2
interfaces can be quantitatively controlled (from 76 to 180). This quantitative control can be precisely manipulated by tuning the interparticle electrostatic interactions (the intermicellar electrostatic repulsion and electrostatic attractions between the monomicelle units and the SiO
2
substrate). This monomicelle interfacial super-assembly strategy will enable a controllable way for building multiscale hierarchical regular micro- and/or macroscale materials and devices.
The butterfly effect: improving brain cone-beam CT image artifacts for stroke assessment using a novel dual-axis trajectory
Authors: Cancelliere Nicole Mariantonia , Hummel Eric , van Nijnatten Fred , van de Haar Peter , Withagen Paul , van Vlimmeren Marijke , Hallacoglu Bertan , Agid Ronit , Nicholson Patrick , Mendes Pereira Vitor
Published: May 2022

Background

Cone-beam computed tomography (CBCT) imaging of the brain can be performed in the angiography suite to support various neurovascular procedures. Relying on CBCT brain imaging solely, however, still lacks full diagnostic confidence due to the inferior image quality compared with CT and various imaging artifacts that persist even with modern CBCT.

Objective

To perform a detailed evaluation of image artifact improvement using a new CBCT protocol which implements a novel dual-axis ‘butterfly’ trajectory.

Methods

Our study included 94 scans from 47 patients who received CBCT imaging for assessment of either ischemia or hemorrhage during a neurovascular procedure. Both a traditional uni-axis ‘circular’ and novel dual-axis ‘butterfly’ protocol were performed on each patient (same-patient control). Each brain scan was divided into six regions and scored out of 3 based on six artifacts originating from various physics-based and patient-based sources.

Results

The dual-axis trajectory produces CBCT images with significantly fewer image artifacts than the traditional circular scan (whole brain average artifact score, AS: 0.20 vs 0.33), with the greatest improvement in bone beam hardening (AS: 0.13 vs 0.78) and cone-beam artifacts (AS: 0.04 vs 0.55).

Conclusions

Recent developments in CBCT imaging protocols have significantly improved image artifacts, which has improved diagnostic confidence for stroke and supports a direct-to-angiography suite transfer approach for patients with acute ischemic stroke.
Travel time and distance for bypass and non-bypass routing of stroke patients in the USA
Authors: Yu Cathy Y , Panagos Peter D , Kansagra Akash P
Published: May 2022

Background

Endovascular thrombectomy is not available at all hospitals that offer intravenous thrombolysis, prompting debate regarding the preferred transport destination for acute ischemic stroke. This study aimed to quantify real-world travel time and distance of bypass and non-bypass transport models for large-vessel occlusion (LVO) and non-LVO stroke.

Methods

This cross-sectional study included population data of census tracts in the contiguous USA from the 2014–2018 United States Census Bureau’s American Community Survey, stroke (thrombolysis-capable) and thrombectomy-capable centers certified by a state or national body, and road network data from a mapping service. Census tracts were categorized by urbanization level. Data were retrieved from March to November 2020. Travel times and distances were calculated for each census tract to each of the following: nearest stroke center (nearest), nearest thrombectomy-capable center (bypass), and nearest stroke center then to the nearest thrombectomy-capable center (transfer). Population-weighted median and IQR were calculated nationally and by urbanization.

Results

72 538 census tracts, 2388 stroke hospitals, and 371 thrombectomy-capable centers were included. Nationally, population-weighted median travel time for nearest and bypass routing was 11.7 min (IQR 7.7–19.3) and 26.4 min (14.8–55.1), respectively. For transfer routing, the population-weighted median travel times with 60 min, 90 min, and 120 min door-in-door-out times were 94.1 min (78.5–127.7), 124.1 min (108.5–157.7), and 154.1 min (138.4–187.6), respectively.

Conclusions

Bypass routing offers modest travel time benefits for LVO patients and incurs modest penalties for non-LVO patients. Differences are greatest in rural areas. A majority of Americans live in areas for which current guidelines recommend bypass.
Occupation, work-related contact and SARS-CoV-2 anti-nucleocapsid serological status: findings from the Virus Watch prospective cohort study
Authors: Beale Sarah , Patel Parth , Rodger Alison , Braithwaite Isobel , Byrne Thomas , Fong Wing Lam Erica , Fragaszy Ellen , Geismar Cyril , Kovar Jana , Navaratnam Annalan , Nguyen Vincent , Shrotri Madhumita , Aryee Anna , Aldridge Robert , Hayward Andrew
Published: May 2022

Objectives

Risk of SARS-CoV-2 infection varies across occupations; however, investigation into factors underlying differential risk is limited. We aimed to estimate the total effect of occupation on SARS-CoV-2 serological status, whether this is mediated by workplace close contact, and how exposure to poorly ventilated workplaces varied across occupations.

Methods

We used data from a subcohort (n=3775) of adults in the UK-based Virus Watch cohort study who were tested for SARS-CoV-2 anti-nucleocapsid antibodies (indicating natural infection). We used logistic decomposition to investigate the relationship between occupation, contact and seropositivity, and logistic regression to investigate exposure to poorly ventilated workplaces.

Results

Seropositivity was 17.1% among workers with daily close contact vs 10.0% for those with no work-related close contact. Compared with other professional occupations, healthcare, indoor trade/process/plant, leisure/personal service, and transport/mobile machine workers had elevated adjusted total odds of seropositivity (1.80 (1.03 to 3.14) − 2.46 (1.82 to 3.33)). Work-related contact accounted for a variable part of increased odds across occupations (1.04 (1.01 to 1.08) − 1.23 (1.09 to 1.40)). Occupations with raised odds of infection after accounting for work-related contact also had greater exposure to poorly ventilated workplaces.

Conclusions

Work-related close contact appears to contribute to occupational variation in seropositivity. Reducing contact in workplaces is an important COVID-19 control measure.
Evaluating the role of transthoracic echocardiography in hospitalised patients with COVID-19 infection
Authors: Babu Aswin , Meng Zhaoyi , Eden Nadia , Lamb Daniel , Nouza Jan , Bhatia Raghav , Chis Ster Irina , Bennett Jonathan , Voon Victor
Published: May 2022

Objective

To identify the most common transthoracic echocardiogram (TTE) parameters in patients hospitalised with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2/COVID-19) and their association with myocardial injury and outcomes.

Methods

A retrospective, single-centre, observational, exploratory cohort study was performed at the height of the COVID-19 pandemic. All SARS-CoV-2 polymerase chain reaction (PCR) positive patients who underwent a TTE during their inpatient admission between 1 March 2020 and 31 October 2020 were analysed. The most frequent cardiovascular risk factor profile and echocardiographic features were investigated.

Results

A total of 87 patients met the eligibility criteria. A salient 41.4% (n=36) of our cohort succumbed to this devastating virus. More than half of our hospital population (58.6%) were admitted to the intensive care unit (ITU) and this was significantly associated with inpatient mortality (OR: 7.14, CI 2.53 to 20.19, p<0.001). Hypertension was the most common cardiovascular risk factor (51.7%) with no additional prominence in non-survivors (OR: 2.33, CI 0.97 to 5.61, p=0.059). Remarkably, 90.8% of our cohort demonstrated a preserved left ventricular ejection fraction, although 69.1% had elevated troponin levels. Only 1 patient (1.1%) was given a diagnostic label of myocarditis. A raised pulmonary artery systolic pressure (36.8%) andright ventricle (RV) dysfunction (26.4%) were the most common echocardiographic features. In particular, the presence of RV dysfunction was significantly related to adverse outcomes (OR: 2.97, CI 1.11 to 7.94, p<0.03).

Conclusions

In this cohort of extremely unwell patients hospitalised with COVID-19 pneumonitis, the presence of RV dysfunction or admission to ITU was significantly associated with inpatient case fatality ratio. Moreover, COVID-19-induced myocarditis remains extremely rare.
Clinical presentations leading to arrhythmogenic left ventricular cardiomyopathy
Authors: Graziosi Maddalena , Ditaranto Raffaello , Rapezzi Claudio , Pasquale Ferdinando , Lovato Luigi , Leone Ornella , Parisi Vanda , Potena Luciano , Ferrara Valentina , Minnucci Matteo , Caponetti Angelo Giuseppe , Chiti Chiara , Ferlini Alessandra , Gualandi Francesca , Rossi Cesare , Berardini Alessandra , Tini Giacomo , Bertini Matteo , Ziacchi Matteo , Biffi Mauro , Galie Nazzareno , Olivotto Iacopo , Biagini Elena
Published: May 2022

Objectives

To describe a cohort of patients with arrhythmogenic left ventricular cardiomyopathy (ALVC), focusing on the spectrum of the clinical presentations.

Methods

Patients were retrospectively evaluated between January 2012 and June 2020. Diagnosis was based on (1) ≥3 contiguous segments with subepicardial/midwall late gadolinium enhancement in the left ventricle (LV) at cardiac magnetic resonanceplusa likely pathogenic/pathogenic arrhythmogenic cardiomyopathy (AC) associated genetic mutationand/orfamilial history of ACand/orred flags for ALVC (ie, negative T waves in V4-6/aVL, low voltages in limb leads, right bundle branch block like ventricular tachycardia) or (2) pathology examination of explanted hearts or autoptic cases suffering sudden cardiac death (SCD). Significant right ventricular involvement was an exclusion criterion.

Results

Fifty-two patients (63% males, age 45 years (31–53)) composed the study cohort. Twenty-one (41%) had normal echocardiogram, 13 (25%) a hypokinetic non-dilated cardiomyopathy (HNDC) and 17 (33%) a dilated cardiomyopathy (DCM). Of 47 tested patients, 29 (62%) were carriers of a pathogenic/likely pathogenic DNA variant. Clinical contexts leading to diagnosis were SCD in 3 (6%), ventricular arrhythmias in 15 (29%), chest pain in 8 (15%), heart failure in 6 (12%) and familial screening in 20 (38%). Thirty patients (57%) had previously received a diagnosis other than ALVC with a diagnostic delay of 6 years (IQR 1–7).

Conclusions

ALVC is hidden in different clinical scenarios with a phenotypic spectrum ranging from normal LV to HNDC and DCM. Ventricular arrhythmias, chest pain, heart failure and SCD are the main clinical presentations, being familial screening essential for the affected relatives’ identification.
Cardiac and obstetric outcomes in pregnant women with heart disease: appraisal of the 2018 mWHO classification
Authors: Ornaghi Sara , Bellante Nicolo' , Abbamondi Alessandra , Maini Marzia , Cesana Francesca , Trabucchi Margherita , Corsi Davide , Arosio Viola , Mariani Silvana , Scian Antonietta , Colciago Elisabetta , Lettino Maddalena , Vergani Patrizia
Published: May 2022

Objective

To appraise the application of the 2018 European Society of Cardiology-adapted modified WHO (mWHO) classification to pregnant women with heart disease managed at our maternal–fetal medicine referral centre and to assess whether the lack of a multidisciplinary Pregnancy Heart team has influenced their outcomes.

Methods

A retrospective cohort study including all pregnancies with heart disease managed at our centre between June 2011 and December 2020. Cardiac conditions were categorised in five classes according to the mWHO classification. An additional class, named X, was created for conditions not included in this classification. Outcomes were compared among all classes and factors potentially associated to cardiac complications were assessed.

Results

We identified 162 women with 197 pregnancies, for a prevalence of 0.7%. Thirty-eight (19.3%) gestations were included in class X. Caesarean section was performed in 64.9% pregnancies in class X, a rate similar to that of class II, II-III, and III/IV, and mostly for obstetric indications; in turn, it was more commonly performed for cardiology reasons in class II–III and III/IV. Cardiac complications occurred in 10.7%, with class X and II pregnancies showing the highest number of events (n=30.8% and 34.6%, respectively). Multiple gestation and urgent caesarean section associated with a 5-fold and 6.5-fold increase in complication rates.

Conclusions

Even in a maternal–fetal medicine referral centre, the lack of a multidisciplinary team approach to women with heart disease may negatively impact their outcomes.
National examination for medical residency admission: academic performance in a high-stakes test and the need for continuing education
Authors: Gaxiola-García Miguel Angel , Villalpando-Casas José de Jesús , García-Minjares Manuel , Martínez-González Adrián
Published: May 2022

Introduction

Performance and selection rate of non-newly graduated physicians in a medical residency admission test as an indicator for the need of continuing education.

Methods

A database comprising 153 654 physicians who took a residency admission test in the period 2014–2018 was analysed. Performance and selection rates were assessed in relation to year of graduation and performance in medical school.

Results

The whole sample scored at a mean of 62.3 (SD ±8.9; range 1.11–91.11). Examinees who took the test in their year of graduation performed better (66.10) than those who took the test after their year of graduation (61.84); p<0.001.

Selection rates differed accordingly; 33.9% for newly graduated physicians compared with 24.8% in those who took the test at least 1 year after graduation; p<0.001. An association between selection test performance and medical school grades was established using Pearson’s correlation: r=0.40 for newly graduated physicians and r=0.30 for non-newly graduated physicians. There were statistically significant differences in selection rates for every ranking group of grades in medical school based on the χ2 test (p<0.001). The selection rates are decreased years after graduation even for candidates with high grades in medical school.

Discussion

There is an association between performance in a medical residency admission test and academic variables of the candidates: medical school grades and time elapsed from graduation to test taking. The evidence of decrease in retention of medical knowledge since graduation highlights the pertinence of continuing education interventions.
Differential attainment in higher surgical training: scoping pan-specialty spectra
Authors: Luton Oliver William , Mellor Katie , Robinson David Bryan Thomas , Barber Zoe , James Osian Penri , Powell Arfon Gethyn Morgan Tregellis , Hemington-Gorse Sarah , Walsh Leona , Egan Richard John , Lewis Wyn Griffith
Published: May 2022

Introduction

This study aimed to evaluate differential attainment during higher surgical training (HST; all specialties) related to three ethnic cohorts: White UK (WUKG), Black and Minority Ethnic UK Graduates (BMEUKG), and International Medical Graduates (IMG).

Method

Anonymised records of 266 HSTs (126 WUKG, 65 BMEUKG, 75 IMG; 7 years) in a single UK Statutory Education Body were examined. Primary effect measures were Annual Record of Competency Progression Outcome (ARCPO) and Fellowship of the Royal College of Surgeons (FRCS) pass.

Results

ARCPOs related to ethnicity and specialty were similar with the exception of general surgery (GS) trainees, four of whom received ARCPO 4 (GS 4.9% (75% BME; p=0.025) vs all other 0%). ARCPO 3 was commoner in women (22/76, (28.9%) than men 27/190 (14.2%), OR 2.46, p=0.006). FRCS pass rates (WUKG vs BMEUKG vs IMG) were 76.9%, 52.9% and 53.9% respectively (p=0.064) but unrelated to gender (M 70.4% vs F 64.3%). On multivariable analyses: ARCPO 3 was associated with Female gender and Maternity Leave (OR 8.05, p=0.001); FRCS pass with ethnicity (OR 0.21, p=0.028) and Hirsch Indices of ≥5 (OR 11.17, p=0.001).

Conclusion

Differential attainment was plain with BMEUKG FRCS performance almost a third poorer than WUKG, and women twofold more likely to receive adverse ARCPOs, with return from statutory leave independently associated with training extension. Focused counter measures targeted at non-operative technical skills (including academic reach), Keeping in Touch, Return to Work, and re-induction programmed support are urgently needed for trainees at risk.

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