1,053 research outputs found
A comparison of methods to estimate anaerobic capacity: Accumulated oxygen deficit and W' during constant and all-out work-rate profiles.
This document is the Pre-Print version of an article first published by Taylor & Francis Group in Journal of Sports Sciences, on December 2016, available online at:http://www.tandfonline.com/doi/full/10.1080/02640414.2016.1267386. The Accepted Manuscript version is under embargo. Embargo end date: 26 June 2018.This study investigated (i) whether the accumulated oxygen deficit (AOD) and curvature constant of the power-duration relationship (W') are different during constant work-rate to exhaustion (CWR) and 3-min all-out (3MT) tests and (ii) the relationship between AOD and W' during CWR and 3MT. Twenty-one male cyclists (age: 40 ± 6 years; maximal oxygen uptake [V̇O2max]: 58 ± 7 ml · kg-1 · min-1) completed preliminary tests to determine the V̇O2-power output relationship and V̇O2max. Subsequently, AOD and W' were determined as the difference between oxygen demand and oxygen uptake and work completed above critical power, respectively, in CWR and 3MT. There were no differences between tests for duration, work, or average power output (P ≥ 0.05). AOD was greater in the CWR test (4.18 ± 0.95 vs. 3.68 ± 0.98 L; P = 0.004), whereas W' was greater in 3MT (9.55 ± 4.00 vs. 11.37 ± 3.84 kJ; P = 0.010). AOD and W' were significantly correlated in both CWR (P < 0.001, r = 0.654) and 3MT (P < 0.001, r = 0.654). In conclusion, despite positive correlations between AOD and W' in CWR and 3MT, between-test differences in the magnitude of AOD and W', suggest that both measures have different underpinning mechanisms.Peer reviewe
The Continuing Burden of Short-Sighted Nuclear Waste Policy. Dominion Res., Inc. v. United States
InP shallow-homojunction solar cells
Indium phosphide solar cells with very thin n-type emitters have been made by both ion implantation and metalorganic chemical vapor deposition. Air mass zero efficiencies as high as 18.8 percent (NASA measurement) have been achieved. Although calculations show that, as is the case with GaAs, a heterostructure is expected to be required for the highest efficiencies attainable, the material properties of InP give the shallow-homojunction structure a greater potential than in the case of GaAs. The best cells, which were those made by ion implantation, show open-circuit voltage (V sub oc) of 873 mV, short-circuit current of 357 A/sq m (35.7 mA/sq cm), and fill factor of 0.829. Improvements are anticipated in all three of these parameters. Internal quantum efficiency peaks at over 90 percent in the red end of the spectrum, but drops to 54 percent in the blue end. Other cells have achieved 74 percent in the blue end. Detailed modeling of the data indicates that a high front surface recombination velocity is responsible for the low blue response, that the carrier lifetime is high enough to allow good carrier collection from both the base and the emitter, and that the voltage is base-limited
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Built With Paint
My current body of work is a group of paintings dealing specifically with a support material along with a structural arrangement and paint, itself, as the integral components whose sum total comprises the form and content of my work. The paintings are divided into three groups; canvas, lattice, and corners. All are interrelated by the fact that they are all paintings about painting, dealing with the basic formal elements of shape, color, space, texture, scale, and second level elements of composition, unity, and proportion.
It is very important to me to keep making additions to my work with new materials and ideas, while keeping them within the context of painting about painting. The paint added to the total structure is not in any sense flat, nor does it simply contain color but the color functions to enhance spacial qualities. Secondary colors add effective small accents in their subordinate place and help to keep assertive colors under control. The color I use in the lines is used with maximum intensity to make the line more dynamic. The areas of shape are formed by the use of dominant colors and line. These shapes are put together to give the illusion of movement and space in a static design. The use of the intense color, line, illusion, and simple shape, helps one become more involved with the contemplation of the paintings within a sort of hypnotic presense.
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Quantitative acoustic analysis of the vocal repertoire of the golden rocket frog (\u3ci\u3eAnomaloglossus beebei\u3c/i\u3e)
This study describes the vocal repertoire of the Guyanan golden rocket frog, Anomaloglossus beebei, a bromeliad specialist with biparental care. Using multivariate analyses of nine call properties, as well as the occurrence of nonlinear phenomena, three signal types were distinguished—advertisement, courtship, and aggressive calls. Although all three call types were composed of a short series of rapidly repeated pulses, advertisement calls were produced at higher amplitudes and had longer pulse durations than both courtship calls and aggressive calls. Courtship calls exhibited lower dominant frequencies than both advertisement and aggressive calls, which had similar dominant frequencies. Aggressive calls had more pulses per call, had longer intervals between calls, and occasionally contained one or two introductory pulses preceding the pulsed call. Several acoustic properties predicted aspects of the signaler\u27s body size and condition. Our study demonstrates the reliability of human observers to differentiate the multiple call types of A. beebei based on hearing calls and observing the social context in which they are produced under field conditions
A Critical Role for Natural Killer T Cells in Immunosurveillance of Methylcholanthrene-induced Sarcomas
Natural killer (NK) T cells initiate potent antitumor responses when stimulated by exogenous factors such as interleukin (IL)-12 or α-galactosylceramide (α-GalCer), however, it is not clear whether this reflects a physiological role for these cells in tumor immunity. Through adoptive transfer of NK T cells from wild-type to NK T cell–deficient (T cell receptor [TCR] Jα281−/−) mice, we demonstrate a critical role for NK T cells in immunosurveillance of methylcholanthrene (MCA)-induced fibrosarcomas, in the absence of exogenous stimulatory factors. Using the same approach with gene-targeted and/or antibody-depleted donor or recipient mice, we have shown that this effect depends on CD1d recognition and requires the additional involvement of both NK and CD8+ T cells. Interferon-γ production by both NK T cells and downstream, non-NK T cells, is essential for protection, and perforin production by effector cells, but not NK T cells, is also critical. The protective mechanisms in this more physiologically relevant system are distinct from those associated with α-GalCer–induced, NK T cell–mediated, tumor rejection. This study demonstrates that, in addition to their importance in tumor immunotherapy induced by IL-12 or α-GalCer, NK T cells can play a critical role in tumor immunosurveillance, at least against MCA-induced sarcomas, in the absence of exogenous stimulation
Foreword
Little information exists about the loss of all one’s teeth (edentulism) among older adults in low- and middle-income countries. This study examines the prevalence of edentulism and associated factors among older adults in a cross-sectional study across six such countries. Data from the World Health Organization (WHO’s) Study on global AGEing and adult health (SAGE) Wave 1 was used for this study with adults aged 50-plus from China (N = 13,367), Ghana (N = 4724), India (N = 7150), Mexico (N = 2315), Russian Federation (N = 3938) and South Africa (N = 3840). Multivariate regression was used to assess predictors of edentulism. The overall prevalence of edentulism was 11.7% in the six countries, with India, Mexico, and Russia has higher prevalence rates (16.3%–21.7%) than China, Ghana, and South Africa (3.0%–9.0%). In multivariate logistic analysis sociodemographic factors (older age, lower education), chronic conditions (arthritis, asthma), health risk behaviour (former daily tobacco use, inadequate fruits and vegetable consumption) and other health related variables (functional disability and low social cohesion) were associated with edentulism. The national estimates and identified factors associated with edentulism among older adults across the six countries helps to identify areas for further exploration and targets for intervention
A survey of X-ray emission from 100 kpc radio jets
We have completed a Chandra snapshot survey of 54 radio jets that are
extended on arcsec scales. These are associated with flat spectrum radio
quasars spanning a redshift range z=0.3 to 2.1. X-ray emission is detected from
the jet of approximately 60% of the sample objects. We assume minimum energy
and apply conditions consistent with the original Felten-Morrison calculations
in order to estimate the Lorentz factors and the apparent Doppler factors. This
allows estimates of the enthalpy fluxes, which turn out to be comparable to the
radiative luminosities.Comment: Conference Proceedings IAU Symposium No. 313, Extragalactic jets from
every angle, pp. 219-224, 4 figure
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