1,178 research outputs found
Effects of a Dynamic Arm Stabilizer on Varus Elbow Torque, Arm Speed, and Velocity in Collegiate Baseball Players: A Pilot Study
Purpose: The purpose of this study was to assess the effect a dynamic arm stabilizer had on varus elbow torque, arm speed, and throw velocity during baseball throwing. Methods: 8 collegiate baseball players (age= 20 ± 1 years, height= 183.5 ± 6.5 cm, weight= 85.6 ± 7.7 kg) participated in this study. Participants were randomly assigned to throw their first set of 25 throws at 90 feet wearing a dynamic arm stabilizer or throw their second set of 25 throws at 90 feet not wearing a dynamic arm stabilizer. After completing the first set of throws, the participants threw a second set of 25 throws at 90 feet in the opposite condition. Elbow varus torque and arm speed were measured using a wearable inertial measurement unit, and throwing velocity was measured in miles per hour using a handheld radar gun. Pearson’s correlations were performed to determine relationships between varus torque, arm speed, and velocity during activity with and without the dynamic arm stabilizer. Then, paired samples t-tests were performed to determine differences between varus torque, arm speed, and velocity with and without the dynamic arm stabilizer. Results: Significant correlations were found between varus torque and arm speed, varus torque and velocity, and arm speed and velocity when wearing the dynamic arm stabilizer. Other correlations found were between varus torque and velocity, and arm speed and velocity when not wearing the dynamic arm stabilizer. Significant differences were found between throwing with the dynamic arm stabilizer and not wearing the dynamic arm stabilizer in varus torque (stabilizer = 45.80 ± 8.12 Nm, no stabilizer = 51.85 ± 8.87 Nm, p \u3c .001), arm speed (stabilizer = 857.39 ± 59.64 degrees per second, no stabilizer = 876.58 ± 82.74 degrees per second, p \u3c .001), and throwing velocity (stabilizer = 70.95 ± 5.21 mph, no stabilizer = 71.77 ± 5.68 mph, p \u3c .001). Conclusions: Use of a dynamic arm stabilizer results in a decrease in varus elbow torque when throwing on flat ground at 90 feet. The dynamic arm stabilizer also resulted in a decrease in arm speed and throwing velocity when compared to throwing without a dynamic arm stabilizer. Further research is needed to determine the clinical meaningfulness of these findings in order to determine the best application for a dynamic arm stabilizer in baseball players
Spatio-temporal patterns in the Diel Vertical Migration of the Copepod Metridia lucens in the Northeast Atlantic derived from the Continuous Plankton Recorder Survey
The archived data set collected over a 45-yr period (1948-1992) by Continuous Plankton Recorders (CPRs) towed in near-surface waters was used to investigate the diel vertical migration of the copepod Metridia lucens in the northeast Atlantic (47-63?N and 10-30?W). Although the CPR sampling intensity was uniform during the day and the night, M. lucens was caught predominantly in samples collected at night, consistent with a normal diel vertical migration pattern involving movement from greater depth during the day to shallower depths at night. The length of time spent near the surface varied seasonally and was closely correlated (r2 = 0.80) with seasonal change in length of night. The residual variation in length of time spent at the surface was nonrandom, with more time being spent at the surface in spring before the onset of the spring bloom, and less time being spent at the surface in autumn, than that predicted from the length of night at these periods. The timing of this enhanced near-surface occupation in spring varied with latitude, occurring a mean of 3.4 d later per degree of latitude
Quantitative proteomics reveals tissue-specific, infection-induced and species-specific neutrophil protein signatures
Neutrophils are one of the first responders to infection and are a key component of the innate immune system through their ability to phagocytose and kill invading pathogens, secrete antimicrobial molecules and produce extracellular traps. Neutrophils are produced in the bone marrow, circulate within the blood and upon immune challenge migrate to the site of infection. We wanted to understand whether this transition shapes the mouse neutrophil protein landscape, how the mouse neutrophil proteome is impacted by systemic infection and perform a comparative analysis of human and mouse neutrophils. Using quantitative mass spectrometry we reveal tissue-specific, infection-induced and species-specific neutrophil protein signatures. We show a high degree of proteomic conservation between mouse bone marrow, blood and peritoneal neutrophils, but also identify key differences in the molecules that these cells express for sensing and responding to their environment. Systemic infection triggers a change in the bone marrow neutrophil population with considerable impact on the core machinery for protein synthesis and DNA replication along with environmental sensors. We also reveal profound differences in mouse and human blood neutrophils, particularly their granule contents. Our proteomics data provides a valuable resource for understanding neutrophil function and phenotypes across species and model systems.</p
Quantitative proteomics reveals tissue-specific, infection-induced and species-specific neutrophil protein signatures
Neutrophils are one of the first responders to infection and are a key component of the innate immune system through their ability to phagocytose and kill invading pathogens, secrete antimicrobial molecules and produce extracellular traps. Neutrophils are produced in the bone marrow, circulate within the blood and upon immune challenge migrate to the site of infection. We wanted to understand whether this transition shapes the mouse neutrophil protein landscape, how the mouse neutrophil proteome is impacted by systemic infection and perform a comparative analysis of human and mouse neutrophils. Using quantitative mass spectrometry we reveal tissue-specific, infection-induced and species-specific neutrophil protein signatures. We show a high degree of proteomic conservation between mouse bone marrow, blood and peritoneal neutrophils, but also identify key differences in the molecules that these cells express for sensing and responding to their environment. Systemic infection triggers a change in the bone marrow neutrophil population with considerable impact on the core machinery for protein synthesis and DNA replication along with environmental sensors. We also reveal profound differences in mouse and human blood neutrophils, particularly their granule contents. Our proteomics data provides a valuable resource for understanding neutrophil function and phenotypes across species and model systems.</p
The Oxford Common File Layout: A common approach to digital preservation
The Oxford Common File Layout describes a shared approach to filesystem layouts for institutional and preservation repositories, providing recommendations for how digital repository systems should structure and store files on disk or in object stores. The authors represent institutions where digital preservation practices have been established and proven over time or where significant work has been done to flesh out digital preservation practices. A community of practitioners is surfacing and is assessing successful preservation approaches designed to address a spectrum of use cases. With this context as a background, the Oxford Common File Layout (OCFL) will be described as the culmination of over two decades of experience with existing standards and practices
Electron spin coherence in metallofullerenes: Y, Sc and La@C82
Endohedral fullerenes encapsulating a spin-active atom or ion within a carbon
cage offer a route to self-assembled arrays such as spin chains. In the case of
metallofullerenes the charge transfer between the atom and the fullerene cage
has been thought to limit the electron spin phase coherence time (T2) to the
order of a few microseconds. We study electron spin relaxation in several
species of metallofullerene as a function of temperature and solvent
environment, yielding a maximum T2 in deuterated o-terphenyl greater than 200
microseconds for Y, Sc and La@C82. The mechanisms governing relaxation (T1, T2)
arise from metal-cage vibrational modes, spin-orbit coupling and the nuclear
spin environment. The T2 times are over 2 orders of magnitude longer than
previously reported and consequently make metallofullerenes of interest in
areas such as spin-labelling, spintronics and quantum computing.Comment: 5 pages, 4 figure
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