1,314 research outputs found
A Case Study Of Muscle Activity In Giant Slalom Skiing
Speed of movement respresents the ability essential for successful performance of a sportsman in many branches of sport. This is especially important in ski-jumping where the skier must develop optimum vertical velocity corresponding to the correct ski-jumping technique in extremely complex and demanding inertial environment. The objective of this investigation was to establish the size of the attained vertical velocity measured both in the field and laboratory conditions; its stability and relation to the jump length. The results of the investigation will be, above all, useful to experts in developing the take-off techniqueElectromyography (EMG) and video data from a single female US. Ski Team
member were acquired during giant slalom (GS) skiing at Beaver Creek, Colorado. The purpose of the testing was to examine muscle activity relative to the skiing motion. Muscles on the right side of the body, consisting of the lower leg (anterior tibialis (AT) and lateral gastrocnemius (LG», thigh (vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF), semitendinosus (ST), gracilis (Gr), and gluteus maximus (GM», and trunk (rectus abdominis . (RA), external oblique (EO), and erector spinae (ES» were monitored.
Maximal voluntary contractions (MVC) were performed pre- and post-skiing to provide a relative reference for the amplitude of muscle activity (%MVC).
EMG during skiing was monitored via a four channel telemetry unit. The eleven muscles were partitioned into three sets. Three skiing trials of a seven gate GS course were completed for each set. Peak amplitude (uv) and time measures (ms) were digitized and averaged across trials for each gate. In six of the eleven muscles, the peak activity occurred when the right leg was the outside leg in a turn (turns 1, 3, 5, 7). The exception to this pattern was for the ES muscles of the lower back. %MVC ranged from 27% (EO at gate 4) to 206% (Gr at gate 5). The coeffcients of variation (CV) ranged from 2.3 (VM at gate 4) to 130% (EO at gate 4), indicating a large amount of variation in arnplitude for several muscle groups. The mean duration of muscle activity across all three muscle sets was consistent, ranging from 1.08 to 1.56 s. Roughly two-thirds of the CV's were less than 14%, indicating that the timing was more consistent than the peak EMG. This case study of EMG activity in GS skiing revealed substantial muscle activity at large percentages of MVC with considerable variation. A large amount of cocontraction between opposing muscles and relatively long duration of muscle activity suggest a quasi static nature of muscle activity during a GS turn. These findings have implications for dryland training of GS skiers. of ski jumpers, and in building a model of performance in ski jumping
Pap Smear Readability on Google: An Analysis of Online Articles Regarding One of the Most Routine Medical Screening Tests
Background: The Papanicolaou smear (Pap smear, Pap test) is one of the most routine screening tests performed in medicine. The development and widespread use of this test has brought a considerable decrease in the incidence of cervical cancer. Unfortunately, this disease process continues to convey significant morbidity and mortality. These persistent phenomena may be the result of inadequate compliance with routine Pap smear screening, in which limited education is thought to play a role, particularly among ethnic minority groups.
Methods: A Google search using the phrase âpap smearâ was performed and the first fourteen web addresses were analyzed using four standardized readability indices: the Flesh-Kinkaid Grade Level, the Simple Measure of Gobbledygook, the Gunning Fog Index and the Automated Readability Index. The average grade level readability was then compared to the American Medical Association recommendation that health care information should be written at a 5th or 6th-grade reading level (i.e., ages 10-12 years).
Results: The average grade-level readability values of the fourteen analyzed sites using the four aforementioned indices were 8.9, 8.8, 11.9, and 8.4, respectively. The mean readability of all four indices was 9.5.
Conclusion: The grade-level readability of commonly accessed internet information regarding Pap smears is above the recommendation of the American Medical Association. Health care providers and website authors should be cognizant of this, as it may impact compliance. This is particularly important given that this routine healthcare test is recommended for nearly fifty percent of the worldâs population at various points throughout their lifetime
Registration of Great Northern Common Bean Cultivar âCoyneâ with Enhanced Disease Resistance to Common Bacterial Blight and Bean Rust
Great northern common bean (Phaseolus vulgaris L.) âCoyneâ (Reg. No. CV-287, PI 655574) was developed by the dry bean breeding program at the University of Nebraska Agricultural Research Division and released in 2008. It was bred specifically for adaptation to Nebraska growing conditions and for enhanced resistance to common bacterial blight (CBB), a major disease of common bean caused by the seed-borne bacterium Xanthomonas campestris pv. phaseoli (Smith) Dye, and bean common rust Uromyces appendiculatus (Pers.:Pers) Unger. Coyne is a great northern F7:8 line derived from a three-way cross (G95023/Weihing//BelMiNeb-RMR-11). The first cross was made in winter 2003. The F7:8 was tested in advanced yield trials at Scottsbluff and Mitchell, NE, and in growersâ fields in Nebraska. Yield of Coyne was only 47 kg haâ1 lower than âMarquisâ in Morrill and Scotts Bluff, NE, counties. Reaction of Coyne to CBB under field conditions was consistent across 3 yr at the West Central Research and Extension Center, North Platte, NE, where fi eld disease ratings of 3.2, 3.5, and 4.4 were recorded in 2005, 2006, and 2007, respectively. Coyne has the Ur-3 and Ur-6 genes for resistance to common bean rust and carries the single dominant hypersensitive I gene that provides resistance to all non-necrotic strains of Bean common mosaic virus. Coyne has bright white seed, blooms 44 d after planting, and is a midseason bean, maturing 91 d after planting
Properties and performance of goat fibre : a review and interpretation of existing research results
Social participation and heat-related behavior in older adults during heat waves and on other days
A detailed investigation of the onion structure of exchanged coupled magnetic Fe3-dO4@CoFe2O4@Fe3-dO4 nanoparticles
Nanoparticles that combine several magnetic phases offer wide perspectives for cutting edge applications because of the high modularity of their magnetic properties. Besides the addition of the magnetic characteristics intrinsic to each phase, the interface that results from core-shell and, further, from onion structures leads to synergistic properties such as magnetic exchange coupling. Such a phenomenon is of high interest to overcome the superparamagnetic limit of iron oxide nanoparticles which hampers potential applications such as data storage or sensors. In this manuscript, we report on the design of nanoparticles with an onion-like structure which has been scarcely reported yet. These nanoparticles consist of a Fe3-dO4 core covered by a first shell of CoFe2O4 and a second shell of Fe3-dO4, e.g., a Fe3-dO4@CoFe2O4@Fe3-dO4 onion-like structure. They were synthesized through a multistep seed-mediated growth approach which consists consists in performing three successive thermal decomposition of metal complexes in a high-boiling-point solvent (about 300 °C). Although TEM micrographs clearly show the growth of each shell from the iron oxide core, core sizes and shell thicknesses markedly differ from what is suggested by the size increasing. We investigated very precisely the structure of nanoparticles in performing high resolution (scanning) TEM imaging and geometrical phase analysis (GPA). The chemical composition and spatial distribution of atoms were studied by electron energy loss spectroscopy (EELS) mapping and spectroscopy. The chemical environment and oxidation state of cations were investigated by 57Fe Mössbauer spectrometry, soft X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD). The combination of these techniques allowed us to estimate the increase of Fe2+ content in the iron oxide core of the core@shell structure and the increase of the cobalt ferrite shell thickness in the core@shell@shell one, whereas the iron oxide shell appears to be much thinner than expected. Thus, the modification of the chemical composition as well as the size of the Fe3-dO4 core and the thickness of the cobalt ferrite shell have a high impact on the magnetic properties. Furthermore, the growth of the iron oxide shell also markedly modifies the magnetic properties of the core-shell nanoparticles, thus demonstrating the high potential of onion-like nanoparticles to accurately tune the magnetic properties of nanoparticles according to the desired applications. © 2021 American Chemical Society
The Charge Form Factor of the Neutron at Low Momentum Transfer from the Reaction
We report new measurements of the neutron charge form factor at low momentum
transfer using quasielastic electrodisintegration of the deuteron.
Longitudinally polarized electrons at an energy of 850 MeV were scattered from
an isotopically pure, highly polarized deuterium gas target. The scattered
electrons and coincident neutrons were measured by the Bates Large Acceptance
Spectrometer Toroid (BLAST) detector. The neutron form factor ratio
was extracted from the beam-target vector asymmetry
at four-momentum transfers , 0.20, 0.29 and 0.42
(GeV/c).Comment: 5 pages, 3 figures, submitted to Phys. Rev. Let
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