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Presents a study which analyzed the piezoresistive response of annealed manganin stress gauges in terms of an elastoplastic model which was used to describe the behavior of nonannealed gauges. Measurements of the calibration curve for gauges; Description of the yield strength of the annealed materials.

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Burgeoning interest in marathons necessitates an understanding of performance determinants. Research has highlighted the importance of diet, training and sleep, yet relations of circadian preference and sleep inertia with marathon performance remain largely unexplored. Because marathons generally start early-to-mid morning, these characteristics may have relevant impact. This study investigates relationships of circadian preference, sleep inertia and their interaction with marathon completion time. Consenting participants in a 2016 large mass-participation city marathon completed self-report questionnaires capturing circadian preference and sleep inertia, along with demographics and other characteristics. Circadian preference and sleep inertia were described across subgroups. Analyses examined the associations and interactions of circadian preference and sleep inertia with marathon completion times, with adjusted analyses accounting for age, sex and sleep health. Participants were marathon finishers (n = 936; 64.5% male; 66.3% young-adults), with a majority reporting morningness tendencies (60.8%). Results supported a linear association between increasing eveningness preference with slower marathon times (p = 0.003; p adjusted  = 0.002), while some support was provided for a linear relationship between greater sleep inertia and slower marathon times (p = 0.04; p adjusted  = 0.07). A significant interaction was observed (p = 0.02; p adjusted  = 0.01), with the directionality suggesting that the circadian preference relationship weakened when sleep inertia severity increased, and vice-versa. Our results suggest deleterious associations of increasing eveningness preference and greater sleep inertia with marathon completion time. These features may aid identifying marathoners who could be at a disadvantage, while also serving as modifiable targets for personalized training regimens preceding competition., (© 2024 The Author(s). Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.)

Blood oxygen level-dependent functional magnetic resonance imaging (BOLD fMRI) arises from a physiological and physical cascade of events taking place at the level of the cortical microvasculature which constitutes a medium with complex geometry. Several analytical models of the BOLD contrast have been developed, but these have not been compared directly against detailed bottom-up modeling methods. Using a 3D modeling method based on experimentally measured images of mice microvasculature and Monte Carlo simulations, we quantified the accuracy of two analytical models to predict the amplitude of the BOLD response from 1.5 to 7 T, for different echo time (TE) and for both gradient echo and spin echo acquisition protocols. We also showed that accounting for the tridimensional structure of the microvasculature results in more accurate prediction of the BOLD amplitude, even if the values for SO 2 were averaged across individual vascular compartments. A secondary finding is that modeling the venous compartment as two individual compartments results in more accurate prediction of the BOLD amplitude compared with standard homogenous venous modeling, arising from the bimodal distribution of venous SO 2 across the microvasculature in our data., (© 2024 John Wiley & Sons Ltd.)

Abstract: McClean, ZJ, Pasanen, K, Lun, V, Charest, J, Herzog, W, Werthner, P, Black, A, Vleuten, RV, Lacoste, E, and Jordan, MJ. A biopsychosocial model for understanding training load, fatigue, and musculoskeletal sport injury in university athletes: A scoping review. J Strength Cond Res 38(6): 1177-1188, 2024-The impact of musculoskeletal (MSK) injury on athlete health and performance has been studied extensively in youth sport and elite sport. Current research examining the relationship between training load, injury, and fatigue in university athletes is sparse. Furthermore, a range of contextual factors that influence the training load-fatigue-injury relationship exist, necessitating an integrative biopsychosocial model to address primary and secondary injury prevention research. The objectives of this review were (a) to review the scientific literature examining the relationship between training load, fatigue, and MSK injury in university athletes and (b) to use this review in conjunction with a transdisciplinary research team to identify biopsychosocial factors that influence MSK injury and develop an updated, holistic biopsychosocial model to inform injury prevention research and practice in university sport. Ten articles were identified for inclusion in this review. Key findings were an absence of injury surveillance methodology and contextual factors that can influence the training load-fatigue-MSK injury relationship. We highlight the inclusion of academic load, social load, and mental health load as key variables contributing to a multifactorial, gendered environmental, scientific inquiry on sport injury and reinjury in university sport. An integrative biopsychosocial model for MSK injury in university sport is presented that can be used to study the biological, psychological, and social factors that modulate injury and reinjury risk in university athletes. Finally, we provide an example of how causal inference can be used to maximize the utility of longitudinally collected observational data that is characteristic of sport performance research in university sport., (Copyright © 2024 National Strength and Conditioning Association.)

Background: Sleep as a biological phenomenon is effective in the performance and recovery of athletes. Questionnaires can be used as a cost-effective initial assessment tool for sleep. The Athlete Sleep Screening Questionnaire (ASSQ) demonstrated a clinically valid instrument for screening relevant sleep issues in athletic populations. Due to the lack of validated tools for adequate screening for sleep difficulties in the Iranian athlete population, the present study was conducted to evaluate the validity and reliability of the Persian version of the ASSQ., Materials and Methods: The translation process was performed using instructions by Beaton et al . Content validity was assessed by a panel of experts. Exploratory and confirmatory factor analysis was performed for two 5-item sleep difficulty scores (SDS) and a 4-item chronotype score. Internal consistency based on Cronbach's alpha and McDonald's omega and stability reliability were used to evaluate reliability., Results: The ASSQ achieved conceptual and semantic equivalence with the original scale. The item-level content validity index (I-CVI) of each item ranged from 0.87 to 1, and the averaging scale-level CVI/average was 0.95. In factor analysis, one factor for SDS and one factor for chronotype score were identified and confirmed. The internal consistency of the SDS scale (α =0.77, Ω =0.83) and chronotype (α =0.74, Ω =0.77) was acceptable. Stability reliability was confirmed for SDS scale (intra-class correlation [ICC] =0.87) and for chronotype (ICC = 0.83)., Conclusion: Persian ASSQ has acceptable psychometric measurement properties as a screening tool to assess sleep in Iranian athletes., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Journal of Research in Medical Sciences.)

Despite sleep health being critically important for athlete performance and well-being, sleep health in marathoners is understudied. This foundational study explored relations between sleep health, individual characteristics, lifestyle factors, and marathon completion time. Data were obtained from the 2016 London Marathon participants. Participants completed the Athlete Sleep Screening Questionnaire (ASSQ) along with a brief survey capturing individual characteristics and lifestyle factors. Sleep health focused on the ASSQ sleep difficulty score (SDS) and its components. Linear regression computed relations among sleep, individual, lifestyle, and marathon variables. The analytic sample (N = 943) was mostly male (64.5%) and young adults (66.5%). A total of 23.5% of the sample reported sleep difficulties (SDS ≥ 8) at a severity warranting follow-up with a trained sleep provider. Middle-aged adults generally reported significantly worse sleep health characteristics, relative to young adults, except young adults reported significantly longer sleep onset latency (SOL). Sleep tracker users reported worse sleep satisfaction. Pre-bedtime electronic device use was associated with longer SOL and longer marathon completion time, while increasing SOL was also associated with longer marathon completion. Our results suggest a deleterious influence of pre-bedtime electronic device use and sleep tracker use on sleep health in marathoners. Orthosomnia may be a relevant factor in the relationship between sleep tracking and sleep health for marathoners.

The intestinal epithelium comprises diverse cell types and executes many specialized functions as the primary interface between luminal contents and internal organs. A key function provided by the epithelium is maintenance of a barrier that protects the individual from pathogens, irritating luminal contents, and the microbiota. Disruption of this barrier can lead to inflammatory disease within the intestinal mucosa, and, in more severe cases, to sepsis. Animal models to study intestinal permeability are costly and not entirely predictive of human biology. Here we present a model of human colon barrier function that integrates primary human colon stem cells into Draper's PREDICT96 microfluidic organ-on-chip platform to yield a high-throughput system appropriate to predict damage and healing of the human colon epithelial barrier. We have demonstrated pharmacologically induced barrier damage measured by both a high throughput molecular permeability assay and transepithelial resistance. Using these assays, we developed an Inflammatory Bowel Disease-relevant model through cytokine induced damage that can support studies of disease mechanisms and putative therapeutics., (© 2023. The Author(s).)

Sleep improves the cognitive and physical performance of athletes. A detailed questionnaire that detects sleep disruptions is required to identify sleep-deprived athletes. This study evaluates the translated Athlete Sleep Screening Questionnaire (ASSQ), a tool suggested by the International Olympic Committee, among Arabic-speaking athletes. The ASSQ was translated into Arabic and examined for floor or ceiling effects, internal consistency, and validity among Arabic-speaking athletes. The Arabic Pittsburgh Sleep Quality Index (PSQI) was employed to assess convergent validity. Ninety athletes (28.9% women) participated and completed this study's questionnaires. The Cronbach's alpha for the ASSQ-Sleep Difficulty Score (SDS) was 0.435, and that of the ASSQ-chronotype was 0.632. The SDS and chronotype subset of the ASSQ demonstrated excellent test-retest reliability, with intraclass correlation coefficients of 0.84 and 0.938, respectively. The ASSQ-SDS correlated positively with the PSQI (0.734, p = 0.001). The ASSQ-chronotype was inversely associated with the PSQI ( p = 0.001). This study's findings can assist clinicians in assessing sleep disorders in sports. The Arabic version of the ASSQ has satisfactory psychometric qualities and can identify clinically relevant sleep problems in athletes.

Background: Due to the rising concern of inadequate sleep, critical analysis is needed for the presence of sleep problems in diverse populations. Research has shown that college athletes may be one such population at risk for sleep disturbances. Poor sleep may lead to physiological, psychological, and cognitive deficits that can impact college athletes academically and athletically. This investigation was performed to examine the relationship of age, sex, and history of concussion on sleep disturbance in college athletes., Methods: A total of 191 collegiate athletes between the ages of 18-26 from a single academic NCAA institution in the Rocky Mountain region of the USA, consented to participate in the study. Participants completed a demographic questionnaire and the Athlete Sleep Screening Questionnaire (ASSQ). Results were analyzed using SPSS Version 27., Results: Primary results revealed that female athletes reported higher sleep disturbance scores when compared to males (U=3643.0, P=0.016). Self-reported sleep disturbances when traveling for sport were higher for females (X(1) = 23.800, P<0.001). Males were also less likely to report daytime dysfunction when traveling for sport (X(1) =22.988, P<0.001). Sleep disturbance had a significant association with age (X(1) =4.145, P=0.042), with older participants (20+ years of age) reporting greater sleep disturbance. Concussion history did not associate with sleep disturbance in the present study., Conclusions: Results suggest that sophomore or older female may be at higher risk for sleep disturbances. Clarifying sex-specific sleep health and understanding the role of age and academic class is crucial to enhance and personalize interventions.

The South Saskatchewan River Basin (SSRB) is considered one of the most intensively farmed regions in Canada, with high densities of livestock and expansive areas of irrigated cropland. We measured concentrations of seven veterinary antimicrobials (VAs) in 114 surface water samples from feedlot environs and 219 samples from irrigation conveyances in the SSRB. Overall, detection frequencies in feedlot environs were 100% for chlortetracycline (CTC) and tetracycline (TC), 94% for monensin (MON), 84% for tylosin (TYL), 72% for lincomycin (LIN), 66% for erythromycin (ERY), and 23% for sulfamethazine (SMZ). For irrigation conveyances, detection frequencies for CTC and TC remained high (94-100%), but dropped to 18% for ERY, 15% for TYL, 10% for MON, and 4% for SMZ. Lincomycin was not detected in irrigation conveyance water. Maximum concentrations of VAs ranged from 1384 µg L -1 (TC) to 17 ng L -1 (SMZ) in feedlot environs while those in irrigation conveyances were 155 ng L -1 (TC) to 29 ng L -1 (ERY). High detection frequencies and median concentrations of VAs in both feedlot environs and irrigation conveyances were associated with high amounts of precipitation. However, an irrigation district (ID) with high livestock density (Lethbridge Northern) did not exhibit higher concentrations of VAs compared to IDs with less livestock, while levels of VAs in irrigation conveyances were less influenced by the degree of surface runoff. The ubiquity of CTC and TC in our study is likely a reflection of its widespread use in intensive livestock operations. Additional investigation is required to link environmental concentrations of VAs with livestock densities and increase our understanding of potential antimicrobial resistance in high-intensity agroecosystems., (© 2022. Crown.)