bluuebunny/crossref_metadata_2025_split huggingface dataset:
Semilunar valve growth and function 10 years after infant heart transplantation: Predicting long‐term outcomes of partial heart transplants
Authors: Rajab Taufiek K. , Abdelrahman Mohamed , Schwartzenburg Elridge J. , Aykut Berk , Turek Joseph W. , McVadon Deani H. 
Published: April 2024

AbstractIntroductionPartial heart transplants are a new type of pediatric transplant that replace defective heart valves with the parts of matched donor hearts containing the necessary valves. Short‐term outcomes of partial heart transplants are excellent, but long‐term outcomes are unknown. In order to predict the long‐term outcomes of partial heart transplants, we evaluated long‐term growth and function of semilunar heart valves transplanted in infancy as part of a heart transplant.MethodsAll children who underwent infant heart transplantation at a single center from 1997 to 2014 were included in this study. Children in whom echocardiograms after heart transplantation and after 10 years were not available for review were excluded. The echocardiograms were reviewed by two authors to analyze semilunar valve annulus diameters, Z‐scores, peak valve gradients, and valve regurgitation. Statistical difference was determined using two‐tailed, paired sample t‐tests with Bonferroni correction for multiple comparisons.ResultsData from 15 patients were analyzed. The aortic valve annulus averaged 1.3 cm (range 0.7–1.8 cm) immediately after transplantation and grew to an average of 1.7 cm (range 1.4–2.3 cm) after 10 years (p < .001). After 10 years, the aortic valve peak gradient avereraged 5.1 mmHg (range 2.1–15.5 mmHg) and none of the valves had more than trivial regurgitation. The pulmonary valve annulus averaged 1.5 cm (range 1.1–2.5 cm) immediately after transplantation and grew to an average of 2.1 cm (range 1.0–2.9 cm) after 10 years (p < .001). After 10 years, the pulmonary valve peak gradient averaged 4.3 mmHg (range 1.1–13.8 mmHg), and 7% of valves had moderate regurgitation.DiscussionSemilunar heart valves transplanted in infancy as part of a heart transplant demonstrate statistically significant growth and excellent function after 10 years. This predicts excellent long‐term outcomes of partial heart transplants.
AnDREB5.1, a A5 group DREB gene from desert shrub Ammopiptanthus nanus, confers osmotic and cold stress tolerances in transgenic tobacco
Authors: Zhu Ming , Zheng Lamei , Cao Shilin , Liu Qi , Wei Shanjun , Zhou Yijun , Gao Fei 
Published: April 2024

AbstractThe Dehydration‐Responsive Element Binding (DREB) subfamily of transcription factors plays crucial roles in plant abiotic stress response. Ammopiptanthus nanus (A. nanus) is an eremophyte exhibiting remarkable tolerance to environmental stress and DREB proteins may contribute to its tolerance to water deficit and low‐temperature stress. In the present study, an A. nanus DREB A5 group transcription factor gene, AnDREB5.1, was isolated and characterized in terms of structure and function in abiotic stress tolerance. AnDREB5.1 protein is distributed in the nucleus, possesses transactivation capacity, and is capable of binding to DRE core cis‐acting element. The transcription of AnDREB5.1 was induced under osmotic and cold stress. Tobacco seedlings overexpressing AnDREB5.1 displayed higher tolerance to cold stress, osmotic stress, and oxidative stress compared to wild‐type tobacco (WT). Under osmotic and cold stress, overexpression of AnDREB5.1 increased antioxidant enzyme activity in tobacco leaves, inhibiting excessive elevation of ROS levels. Transcriptome sequencing analysis showed that overexpression of AnDREB5.1 raised the tolerance of transgenic tobacco seedlings to abiotic stress by regulating multiple genes, including antioxidant enzymes, transcription factors, and stress‐tolerant related functional genes like NtCOR413 and NtLEA14. This study provides new evidence for understanding the potential roles of the DREB A5 subgroup members in plants.
Feedback regulation of the isoprenoid pathway by SsdTPS overexpression has the potential to enhance plant tolerance to drought stress
Authors: Yao Xiangyu , Li Rui , Liu Yanan , Song Peng , Wu Ziyi , Yan Meilin , Luo Jinmei , Fan Fenggui , Wang Yingjuan 
Published: April 2024

AbstractIn order to maintain the dynamic physiological balance, plants are compelled to adjust their energy metabolism and signal transduction to cope with the abiotic stresses caused by complex and changeable environments. The diterpenoid natural compound and secondary metabolites, sclareol, derived from Salvia sclarea, has gained significant attention owing to its economic value as a spice material and diverse physiological activities. Here, we focused on the roles and regulatory mechanisms of the sclareol diterpene synthase gene SsdTPS in the resistance of S. sclarea to abiotic stresses. Our results suggested that abiotic stresses could induce the response and upregulation of SsdTPS expression and isoprenoid pathway in S. sclarea. Ectopic expression of SsdTPS conferred drought tolerance in transgenic Arabidopsis, compared with wild‐type. Overexpression of SsdTPS enhanced the transcription of ABA signal transduction synthetic regulators and induced the positive feedback upregulating key regulatory genes in the MEP pathway, thereby promoting the increase of ABA content and improving drought tolerance in transgenic plants. In addition, SsdTPS‐overexpressed transgenic Arabidopsis improved the responses of stomatal regulatory genes and ROS scavenging enzyme activities and gene expression to drought stress. This promoted the stomatal closure and ROS reduction, thus enhancing water retention capacity and reducing oxidative stress damage. These findings unveil the potentially positive role of SsdTPS in orchestrating multiple regulatory mechanisms and maintaining homeostasis for improved abiotic stress resistance in S. sclarea, providing a novel insight into strategies for promoting drought resistance and cultivating highly tolerant plants.
Predicting the cryotolerance of boar sperm through antioxidant stress
Authors: Wang Shih‐Chung , Wu Yi‐Ying , Chen Ming‐Cheng 
Published: April 2024

AbstractHigh sperm cryotolerance is crucial to the successful cryopreservation of boar sperm. Evaluating the cryotolerance of boar sperm by using a rapid and convenient technique can enhance the commercial viability of these sperm. This study investigated the correlation between sperm parameters for three sample subsets—fresh sperm, sperm with H2O2‐induced oxidative damage (hereinafter referred to as H2O2‐induced sperm), and frozen‐thawed sperm—to identify the potential of these correlations to predict cryotolerance. A total of 64 sperm samples were obtained from 64 Duroc boars. The sperm parameters of the three subsets, where the frozen‐thawed sperm were analysed at 30 or 180 min after thawing, were determined, and the coefficients of correlation between these parameters were calculated. The results indicated that H2O2‐induced oxidative stress resulted in decreases in various sperm parameters—including total motility (TM), viability (VIA), mitochondrial membrane potential (MMP), and live sperm with MMP (LMP)—but increased their coefficients of variation. Receiver operating characteristic (ROC) curve analysis revealed that the kinematic parameters of the H2O2‐induced sperm effectively predicted those of the frozen‐thawed boar sperm at 30 min after thawing; the corresponding area under the ROC curve (AUC) was 0.8667 for TM and 0.8733 for progressive motility in the H2O2‐induced sperm. For measurement at 180 min after thawing, the sperm membrane and mitochondrial parameters of the H2O2‐induced sperm effectively predicted the LMP of the frozen‐thawed boar sperm; the corresponding AUC was 0.8489 for VIA, 0.8289 for MMP, and 0.8444 for LMP. To our knowledge, this is the first study to directly establish a strong correlation between post‐thaw boar sperm quality and H2O2‐induced oxidative stress before freezing. Our proposed technique can serve as a valuable reference for the development of practical applications aimed at enhancing techniques for cryopreserving boar sperm.
Chemical diversity in angiosperms − monoterpene synthases control complex reactions that provide the precursors for ecologically and commercially important monoterpenoids
Authors: Srividya Narayanan , Kim Hoshin , Simone Raugei , Lange Bernd Markus 
Published: April 2024

SUMMARYMonoterpene synthases (MTSs) catalyze the first committed step in the biosynthesis of monoterpenoids, a class of specialized metabolites with particularly high chemical diversity in angiosperms. In addition to accomplishing a rate enhancement, these enzymes manage the formation and turnover of highly reactive carbocation intermediates formed from a prenyl diphosphate substrate. At each step along the reaction path, a cationic intermediate can be subject to cyclization, migration of a proton, hydride, or alkyl group, or quenching to terminate the sequence. However, enzymatic control of ligand folding, stabilization of specific intermediates, and defined quenching chemistry can maintain the specificity for forming a signature product. This review article will discuss our current understanding of how angiosperm MTSs control the reaction environment. Such knowledge allows inferences about the origin and regulation of chemical diversity, which is pertinent for appreciating the role of monoterpenoids in plant ecology but also for aiding commercial efforts that harness the accumulation of these specialized metabolites for the food, cosmetic, and pharmaceutical industries.
A corpus‐based analysis of adjective amplification in Hong Kong, Indian and Philippine English
Authors: Schweinberger Martin 
Published: April 2024

AbstractThis study considers a corpus‐based approach for analysing adjective amplifier systems (very, really, so, etc.) in Hong Kong English (HKE), Indian Englsih (IndE) and Philippine English (PhiE) based on data from the International Corpus of English. The current study adds to existing research by providing insights into the understudied adjective amplifier systems of Asian Englishes. The study describes the amplifier systems in HKE, IndE and PhiE, and it ascertains if these amplifier systems are undergoing change. In the latter context, the analysis assesses if really or so is replacing very as the dominant adjective amplifier in these varieties—a trend shown to be at work in Inner Circle varieties of English. The results of Conditional Inference Trees show that the amplifier systems of HKE and IndE are very stable and amplifier choice in these varieties is determined predominately by intra‐linguistics factors (adjective type, syntactic context and semantic category). In contrast, the amplifier system of PhiE shows notable signs of ongoing change, which is driven predominately by social factors (age and gender of speakers). The results indicate that during stasis and initial stages of change, language‐internal factors determine amplifier choice, while social factors become more important once changes have reached the midrange. The paper argues that once certain variants (really and so) gain social meaning, it is this social meaning (the association with specific social groups) that drives and accelerates change as speakers want to associate with social groups that carry covert prestige.
A network analysis of the local pig supply chain in a repeated outbreak area of human streptococcosis in Thailand
Authors: Tungwongjulaniam Chanatda , Klinman Kitipong , Theerawat Ratana , Wiratsudakul Anuwat 
Published: April 2024

AbstractAimsThe present study employed a network analysis approach to scrutinize a pig supply chain in a repeated outbreak province for human streptococcosis in Thailand and identified important actors that should be focused on for tailoring appropriate interventions.Methods and ResultsNakhon Sawan province was chosen as the study site as the cases of human streptococcosis have been consecutively reported since 2014, with the number of cases ranging from 21 to 63. A questionnaire survey was used to collect data from actors along the pig supply chain, including pig farms, slaughterhouses, pork sellers, restaurants and customers. A one‐mode‐directed network was then constructed. Degree and betweenness centrality values were measured. We found that the supply chain of pork products comprised 314 nodes and 296 directed ties. A retailer got the highest overall degree, out‐degree and betweenness centrality values at 35, 34, and 65.3, respectively. For in‐degree centrality, the highest was identified in a customer at 9. Interestingly, this customer bought pork products from nine different mobile groceries.ConclusionsBoth public health and veterinary authorities should extend their surveillance activities to cover all actors in the supply chain to strengthen overall disease prevention and control for streptococcosis.
Motor learning changes the axon initial segment of the spinal motoneuron
Authors: Wang Yu , Chen Yi , Chen Lu , Herron Bruce J. , Chen Xiang Yang , Wolpaw Jonathan R. 
Published: April 2024

AbstractWe are studying the mechanisms of H‐reflex operant conditioning, a simple form of learning. Modelling studies in the literature and our previous data suggested that changes in the axon initial segment (AIS) might contribute. To explore this, we used blinded quantitative histological and immunohistochemical methods to study in adult rats the impact of H‐reflex conditioning on the AIS of the spinal motoneuron that produces the reflex. Successful, but not unsuccessful, H‐reflex up‐conditioning was associated with greater AIS length and distance from soma; greater length correlated with greater H‐reflex increase. Modelling studies in the literature suggest that these increases may increase motoneuron excitability, supporting the hypothesis that they may contribute to H‐reflex increase. Up‐conditioning did not affect AIS ankyrin G (AnkG) immunoreactivity (IR), p‐p38 protein kinase IR, or GABAergic terminals. Successful, but not unsuccessful, H‐reflex down‐conditioning was associated with more GABAergic terminals on the AIS, weaker AnkG‐IR, and stronger p‐p38‐IR. More GABAergic terminals and weaker AnkG‐IR correlated with greater H‐reflex decrease. These changes might potentially contribute to the positive shift in motoneuron firing threshold underlying H‐reflex decrease; they are consistent with modelling suggesting that sodium channel change may be responsible. H‐reflex down‐conditioning did not affect AIS dimensions. This evidence that AIS plasticity is associated with and might contribute to H‐reflex conditioning adds to evidence that motor learning involves both spinal and brain plasticity, and both neuronal and synaptic plasticity. AIS properties of spinal motoneurons are likely to reflect the combined influence of all the motor skills that share these motoneurons.
imageKey points
Neuronal action potentials normally begin in the axon initial segment (AIS). AIS plasticity affects neuronal excitability in development and disease. Whether it does so in learning is unknown.
Operant conditioning of a spinal reflex, a simple learning model, changes the rat spinal motoneuron AIS. Successful, but not unsuccessful, H‐reflex up‐conditioning is associated with greater AIS length and distance from soma. Successful, but not unsuccessful, down‐conditioning is associated with more AIS GABAergic terminals, less ankyrin G, and more p‐p38 protein kinase.
The associations between AIS plasticity and successful H‐reflex conditioning are consistent with those between AIS plasticity and functional changes in development and disease, and with those predicted by modelling studies in the literature.
Motor learning changes neurons and synapses in spinal cord and brain. Because spinal motoneurons are the final common pathway for behaviour, their AIS properties probably reflect the combined impact of all the behaviours that use these motoneurons.
Reducing the Constrained Multibody Dynamics Problem to the Solution of a System of Ordinary Differential Equations Via Velocity Partitioning and Lie Group Integration
Authors: Kissel Alexandra , Bakke Luning , Negrut Dan 
Published: April 2024

Abstract
In multibody dynamics, formulating the equations of motion in absolute Cartesian coordinates results in a set of index-3 differential algebraic equations (DAEs). In this work, we present an approach that bypasses the DAE problem by partitioning the velocities in the system into dependent and independent coordinates, thereby reducing the task of producing the time evolution of the mechanical system to one of solving a set of ordinary differential equations (ODEs). In this approach, the independent coordinates are integrated directly, while the dependent coordinates are recovered through the kinematic constraint equations at the position and velocity levels. Notably, Lie group integration is employed to directly obtain the orientation matrix A at each time-step of the simulation. This eliminates the need to choose generalized coordinates to capture the orientation of a body, as the matrix A is a by-product of the solution algorithm. Herein, we outline the new approach and demonstrate it in conjunction with four mechanisms: a single pendulum, a double pendulum, a four-link mechanism, and a slider crank. We report on the convergence order behavior of the proposed method and compare its performance with an established method that combines coordinate partitioning with an Euler parameter formulation. The Python code developed to generate the reported results is open-source and available in a public repository for reproducibility studies.
Design and Analysis of a Symmetric Overconstrained Compliant Tilt/Tip Stage Based on a Hybrid Transmission Ratio Model
Authors: Yang Jian , Yan Peng 
Published: April 2024

Abstract
Developing a compliant mechanism that have potential in parasitism suppression and cross-axis decoupling is a major challenge to meet the requirement of spatial micro-/nano positioning. This work introduces a compliant tilt/tip stage design with a symmetric and overconstrained configuration that is equipped with four reverse bridge notch flexure amplifiers (RBNFAs) and five revolute notch flexure hinges as multiaxis decoupled structures. A hybrid transmission ratio model is developed to describe the mechanical behavior of this stage using elastic beam and pseudo-rigid-body theories. Finite element analysis (FEA) confirmed the analytical model results. A comprehensive study is performed based on FEA model to validate the influence of a particular configuration on parasitic motion and decoupling effect. A prototype stage is 3D printed and experimentally tested, which confirmed the predictions of the analytical hybrid model. In addition, further analysis was conducted to examine the static mechanical characteristics and parasitic behavior of the stage.
Particle Bounce Stick Behavior in the Rotating Frame of Reference
Authors: Gaskell Jack G. , McGilvray Matthew , Gillespie David R. H. , Irving John 
Published: April 2024

Abstract
Particle deposition is a major damage mechanism for gas turbine components, especially in the secondary air system. Predicting the transport and deposition of ingested atmospheric contaminants is of great interest in component-level simulations. Bounce stick models predict deposition upon collision with a wall during Lagrangian particle tracking; they consider a range of physical phenomena, including van der Waals forces and plastic deformation. The effect of the rotating frame of reference on particle collision physics has thus far been neglected in the literature despite the significant centrifugal (CF) loads experienced by many components of interest for deposition studies, for example, turbine blades. The collision physics of the rotating frame are discussed here using low-order models and Monte Carlo style simulations. The present work aims to provide a conceptual framework for the inclusion of CF forces in collision physics. No significant effect was found on the rebound velocities of particles experiencing “worst case” CF forces. However, differences were observed in the sticking probability between concave and convex rotating surfaces, where the CF forces act in opposing directions to either push the particle into the surface or detach it. A force-based analogy of the popular critical velocity model was developed to study the phenomenon. It was used in a Monte Carlo style simulation of a rotor disk, finding that the variation of critical velocity due to CF forces was likely to bias deposition toward concave surfaces. The collision physics of the rotating frame were found to be unintuitive, with complex implications for modeling deposition in gas turbine components. However, they were consequential in determining the distribution of deposition through the system, hence should be included in particle deposition simulations in computational fluid dynamics (CFD).
Using Fluid Curtains to Improve Sealing Performance in Turbomachinery Applications
Authors: MacCalman J. A. , Williams R. J. , Ingram G. L. , Hogg S. I. 
Published: April 2024

Abstract
The results from an investigation into the physics of how fluid curtains can be applied to improve the aerodynamic performance of conventional turbomachinery shaft and rotor seals are described in this paper. Computational fluid dynamics and testing on two experimental facilities are used in the study. In the first part of the work, computational fluid dynamics simulations validated against experimental test data demonstrate the fundamental mechanism by which the presence of the curtain can act to reduce leakage flow through conventional seals. These results are consolidated into a single performance carpet map, showing how the leakage reduction performance and the curtain supply pressure needed to achieve it vary with changes in values of key geometrical parameters. In the second part of the work the effect of swirl in the seal inlet flow, as is often encountered in turbomachinery applications, on the performance of the fluid curtain is investigated experimentally. Test results show that if the swirl momentum in the inlet flow is greater than the momentum of the curtain flow, the performance benefit from applying the curtain is greatly diminished. Overall, the results provide some fundamental design rules for applying fluid curtains to enhance turbomachinery sealing performance for the general type of leakage path geometry (cylindrical channel, 45-deg jet angle, curtain upstream of a conventional seal) and working fluid type and conditions (air, ambient temperature, subsonic leakage channel flow) used in the study.
Understanding the Tribocorrosion Synergism of Laser Shock Peened Steel Deposited by Cold-Spray Additive Manufacturing
Authors: Ralls Alessandro M. , Frizell Jacob , Menezes Pradeep L. 
Published: April 2024

Abstract
In this work, laser shock peening (LSP) was utilized as a surface-processing technique to modify the tribocorrosion characteristics of cold-spray (CS) 316L SS. Results indicate that with the influence of LSP, the degree of wear–corrosion synergism was effectively decreased. Particularly, the degree of wear loss being accelerated by electrochemical degradation was effectively reduced due to the cumulative effects of refined crystallinity, increased surface hardness, closure of surface pores, and decrease in wettability. Consequentially, the wear mechanism transitioned from being an abrasive type with cracking and delamination to an abrasive type free of any defects. From these findings, it can be inferred that LSP is indeed a viable method to improve the tribocorrosion characteristics of CS 316L SS.