255 research outputs found

    Comparative Analysis of Heart Rate Variability Between Traditional Sets and Rest Redistribution

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    Resistance exercise methods have different effects on the cardiovascular system. During skeletal muscular contraction, heart rate increases while heart rate variability (HRV) decreases. HRV is thought to represent the complex interaction between the sympathetic and parasympathetic branches of the autonomic nervous system. PURPOSE: This study analyzed heart rate variability during two methods of resistance exercise, traditional sets (TS) and rest redistribution sets (RR), both containing the same volume and total rest time. METHODS: Twenty-five participants (Mean ± SD: Age= 22.4 ± 3.7 y.; height = 167.5 ± 9.7 cm; body mass = 72.7 ± 14.7 kg) completed 40 repetitions of the barbell squat with 65% 1RM load. Participants completed TS (4 sets of 10 repetitions, 3-minute rest) and RR (10 sets of 4 repetitions, 1-minute rest), in a randomized order on separate days. HRV was collected from each participant using a heart rate monitor. The HRV was analyzed using a specialized software. Average windows were developed to calculate the root mean square of successive differences (RMSSD) between normal heartbeats and stress index (SI) at rest, during the exercise session, and during recovery. Log transformation was performed in the case of a violation of the normality assumption. Paired t-tests were used to compare RMSSD and SI responses at initial rest, during exercise and recovery between TS and RR. RESULTS: During the initial rest period, there were no statistical differences between RR and TS in RMSSD (p=0.36; 7.85 ± 44.2 vs. 9.14 ± 6.63, respectively or SI (p=0.81; 3.50 ± 0.43 vs. 3.41 ±0.60, respectively). However, there were statistical significance for both RMSSD (pCONCLUSION: While the vagal response does not seem to be affected by training method during recovery, stress responses were higher during RR than TS exercise, as measured by HRV. Future studies can examine HRV behavior during exercise and establish its relationship to other physiological and perceptual markers

    UC-69 Team 10B BChain

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    BChain is a new P2P file sharing system that is fully private, anonymous, globally self-verifying, and utilizes an automatic peer-maintained network of trust in data, accomplished through new methods of routing content over the whole network, encrypted, rather than per torrent download. Verification is done by adding file metadata to a blockchain giving the network consistent knowledge of each file it can transfer, and how to verify file received against the network. This enables a policy of zero trust against peers. This system is implemented by an app that interfaces with the network using the protocol, using it for upload, download and file discovery. The interface is built using web technologies, which allows for flexible use across native platforms.Advisors(s): Prof. Ken HogansonTopic(s): IoT/Cloud/NetworkingCS 485

    Examining Stroke Volume Changes During Exercise in Healthy Young Adults

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    Cardiac output is determined by the combination of heart rate and stroke volume. While heart rate is primarily influenced by cardiac autonomic input, stroke volume\u27s behavior is more intricate due to the interplay between myocardial response to stretch (Frank-Starling law) and adrenergic changes in contractility. No consensus exist on its behavior during exercise despite extensive data. PURPOSE: The aim of this study was to assess how normalized stroke volume scores (SV) change in young, healthy adult males during a graded exercise test to exhaustion (GXT). METHODS: Participants (n=20; age=22.9±2.4; BMI=23.7±2.4) were instructed to abstain from engaging in vigorous exercise for a period of 24 hours before the study, ensure they were adequately hydrated, and maintain a fasting state. Participants completed a graded exercise test to exhaustion in the morning on an electromagnetically braked cycle ergometer. SV was recorded using trans-thoracic bioimpedance device and results were averaged and normalized into five epochs. To determine the effect of GXT epochs on SV score, SV was normalized to percentage of within- subject maximum SV, and mean SV was quantified across 10 equally spaced epochs (10% of trial duration each). A mixed model was used to compare epochs. Assumptions of residual normality and homoscedasticity were visually verified using q-q plots and model predicted scores vs. residuals plots, respectively. SV score was modeled using participant as a random effect, and GXT epochs as fixed effects. Follow-up pairwise comparisons utilized Holm sequential corrections. Alpha was set at 0.05. RESULTS: There were no significant differences (p\u3e.05) between epochs 1 (85.2%±5.7) and 2 (86.6%±5.4), epochs 2 and 3 (88.8%±4.1), or among epochs 3 through 10 (91.4%±3.5). There were significant differences (p\u3c0.01) between epochs 1 and 3-10. There were significant differences between epochs 2 and 4-10. CONCLUSION: SV exhibited a general increase throught the first 30% of test duration. However, beyond this point, there was no statistically significant increase in stroke volume, indicating a relatively stable pattern after the first 30% of the test. These results in agreement with previous data that have reported a plateau in stroke volume during progressive exercise to exhaustion

    La troponine T ultrasensible : un nouvel outil diagnostic pour le médecin sportif?

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    peer reviewedIntroduction : Le risque d’accidents cardiaques ou de mort subite après effort physique intense est bien connu. Ces évènements indésirables se produisent souvent chez des sujets présentant une maladie coronarienne asymptomatique et ignorée. Néanmoins, vu ce risque, l’American Heart Association recommande de réaliser un screening cardiovasculaire chez les athlètes de tout âge. Dans cette optique, le dosage de marqueurs cardiaques de nouvelle génération, plus sensibles, comme la troponine T ultrasensible (hsTnT) peut certainement apporter des informations très intéressantes par la détection de dommages myocardiques mêmes mineurs. Matériels et méthodes : Des 20 sujets masculins volontaires âgés de 22.36±2.02 années, sédentaires, 8 ont dû être exclus (abandon, malaise à l’effort...). La VO2max a été préalablement déterminée lors d’un test à l’effort sur cycloergomètre une semaine avant le test afin de ne pas interférer avec les résultats de l’effort physique intense (EPI) pour lequel les sujets ont couru sur tapis roulant durant 1 heure à 75% de la VO2max. Quatre échantillons sanguins de 5 ml (tube hépariné-lithium) ont été prélevés : juste avant (T1), directement après (T2), 4 heures après (T3) et 24 heures après l’EPI (T4). Le dosage de hsTnT (Modular de Roche Diagnostic®) est réalisé sur du plasma par une technique d’électrocheminiluminescence. Résultats : Une augmentation statistiquement significative des résultats à T3 (p<0.01) est observée. L’élévation de la hsTnT est progressive pour atteindre un pic maximum à T3 et revenir dans les normes à T4. Le seuil critique de 0.03 ng/mL a été retenu et 75% des sujets présentent un taux supérieur à ce dernier à T3 (moyenne : 0.053 ng/mL), alors que 100% des sujets se trouvent en dessous de ce seuil à T1 (0.0041 ng/mL). Discussion - Conclusions : Ces résultats, extrêmement intéressants, suggèrent que la libération de hsTnT serait due soit à un processus physiologique de remodelage, soit à un processus irréversible de lésions au niveau des cardiomyocytes (nécrose). Il est également possible que cette élévation des troponines soit due à une libération à partir du pool cytosolique mais aussi elle peut être la conséquence de dommages membranaires potentiellement induits par le stress oxydatif. A l’issue de cette étude, nous démontrons que la hsTnT peut être un nouvel outil diagnostic dans le domaine de la cardiologie du sport

    A novel neutralization sensitive and subdominant RAP-1-related antigen (RRA) is expressed by Babesia bovis merozoites

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    Objective. The Babesia bovis genome encodes a rap-1 related gene denominated RAP-1 related antigen (RRA). In this study, we analysed the pattern of expression, immunogenicity and functional relevance of RRA. Methods. Phylogenetic analysis was performed using the program Phylip. Expression of rra was analysed by Northern blots, RT-PCR, immunoprecipitation, Western blots and immunofluorescence. RRA antigenicity was tested by T-cell proliferation and Western blot analysis, and functional relevance was determined in an in vitro neutralization assay. Results. RRA is more closely related to RAP-1b of Babesia bigemina than to B. bovis RAP-1, and it is highly conserved among distinct strains. Transcriptional analysis suggests lower numbers of rra transcripts compared to rap-1. Immunoprecipitation of metabolically labelled B. bovis proteins with antibodies against synthetic peptides representing predicted antigenic regions of RRA confirmed the expression of a ∼43 kDa RRA in cultured merozoites. Antibodies present in B. bovis hyperimmune sera, but not in field-infected cattle sera, reacted weakly with recombinant RRA, and no significant stimulation was obtained using recombinant RRA as antigen in T-cell proliferation assays, indicating that RRA is a subdominant antigen. Antibodies against RRA synthetic peptides reacted with merozoites using immunofluorescence, and were able to significantly inhibit erythrocyte invasion in in vitro neutralization tests, suggesting functional relevance for parasite survival. Conclusion. B. bovis express a novel subdominant RAP-1-like molecule that may contribute to erythrocyte invasion and/or egression by the parasite.Fil: Suarez, Carlos E.. United States Department of Agriculture. Agriculture Research Service; Estados Unidos. Washington State University; Estados UnidosFil: Laughery, Jacob M.. Washington State University; Estados UnidosFil: Bastos, Reginaldo G.. Washington State University; Estados UnidosFil: Johnson, Wendell C.. United States Department of Agriculture. Agriculture Research Service; Estados UnidosFil: Norimine, Junzo. Washington State University; Estados UnidosFil: Asenzo, Gustavo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Brown, Wendy C.. Washington State University; Estados UnidosFil: Jacobsen, Monica Ofelia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Goff, Will L.. United States Department of Agriculture. Agriculture Research Service; Estados Unido

    Cell lineage transport: a mechanism for molecular gradient formation

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    Gradient formation is a fundamental patterning mechanism during embryo development, commonly related to secreted proteins that move along an existing field of cells. Here, we mathematically address the feasibility of gradients of mRNAs and non-secreted proteins. We show that these gradients can arise in growing tissues whereby cells dilute and transport their molecular content as they divide and grow, a mechanism we termed ‘cell lineage transport.' We provide an experimental test by unveiling a distal-to-proximal gradient of Hoxd13 in the vertebrate developing limb bud driven by cell lineage transport, corroborating our model. Our study indicates that gradients of non-secreted molecules exhibit a power-law profile and can arise for a wide range of biologically relevant parameter values. Dilution and nonlinear growth confer robustness to the spatial gradient under changes in the cell cycle period, but at the expense of sensitivity in the timing of gradient formation. We expect that gradient formation driven by cell lineage transport will provide future insights into understanding the coordination between growth and patterning during embryonic development

    The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

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    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected
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