106 research outputs found
Preliminary Solar Sail Design and Fabrication Assessment: Spinning Sail Blade, Square Sail Sheet
Blade design aspects most affecting producibility and means of measurement and control of length, scallop, fullness and straightness requirements and tolerances were extensively considered. Alternate designs of the panel seams and edge reinforcing members are believed to offer advantages of seam integrity, producibility, reliability, cost and weight. Approaches to and requirements for highly specialized metalizing methods, processes and equipment were studied and identified. Alternate methods of sail blade fabrication and related special machinery, tooling, fixtures and trade offs were examined. A preferred and recommended approach is also described. Quality control plans, inspection procedures, flow charts and special test equipment associated with the preferred manufacturing method were analyzed and are discussed
Tag retention, wound healing, and subsequent reproductive history of southern right whales following satellite-tagging
This paper presents data from 48 resightings of 16 southern right whales that
were satellite-tagged on the South African coast in September 2001, up to and
including 2012. Tag performance in terms of number of days with locations received
was significantly higher in males than females, and lowest in cows with calves, and
attributed to behavioral differences leading to variable degrees of antenna damage.
Resightings occurred from 4 to 4,054 d after tagging: tags were retained in all
whales seen within 27 mo, but were apparently shed in all but one individual seen
within 36 mo of tagging. The exception was a whale that still had the tag present
11 yr after tagging. Healing at the tag site occurred gradually and within 5 yr of
tagging (and 2 yr after tag shedding). No significant difference in the subsequent
frequency of calving was detected between 12 tagged and 382 untagged females
photographed contemporaneously, and although statistical power was low, a 21% or
greater reduction in calving rate in tagged females would seem incompatible with
the observations. The death of one female 3 yr after tagging was more likely attributable
to a ship strike on an animal debilitated by a prolapsed uterus.U.S. National Marine Fisheries Service, Office of Naval Research and gifts from donors to the Oregon State University Marine Mammal Program.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1748-76922016-04-30hb201
Coastal, offshore, and migratory movements of South African right whales revealed by satellite telemetry
In September 2001, 21 satellite-monitored radio tags were deployed on southern right
whales in South African waters, 15 of which transmitted for 25-161 d. Most coastwise
movement on the south coast occurred in a westerly direction with cow-calf pairs
moving slowest. Three whales tagged on the west coast and one tagged on the south
coast moved north into St Helena Bay, a probable feeding ground, where residence
times were 36-100 d. Five animals tracked after leaving the coast maintained a
bearing of 201-220o before branching out over the southeast Atlantic from 37-60o S
and between 13o W and 16o E, travelling 3800-8200 km over the ensuing 53-110 d
before transmissions ceased. Their locations were categorized as migrating or nonmigrating
based on the relative orientation of the track and net speed. An average of
42% of non-migrating locations were between 37-45o S and 53% south of 52o S,
possibly associated with the Sub Tropical Convergence and Antarctic Polar Front
respectively. Whaling data suggest right whales fed largely on copepods at the former
and euphausiids at the latter. If the non-migrating locations represented feeding at
these frontal zones, switching between them would seem to have obvious cost-benefit
implications.P. B. B. acknowledges the support of the
National Research Foundation of South Africa (GUN number 2047517). B. R. M. acknowledges
the support of the National Oceanic and Atmospheric Administration through the
Northeast Consortium, based at the University of New Hampshire (Grant #NA16FL1324),
the U.S. Office of Naval Research, and donors to the Oregon State University Endowed Marine
Mammal Program.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1748-7692ab201
The Effects of Palm Cooling on Repeat Sprint Performance Following Fatigue in Collegiate Female Athletes
Determination of the Proton Spin Structure Functions for 0.05 \u3c Q\u3csup\u3e2\u3c/sup\u3e \u3c5GEV\u3csup\u3e2\u3c/sup\u3e Using CLAS
We present the results of our final analysis of the full data set of gp1 Q2, the spin structure function of the proton, collected using CLAS at Jefferson Laboratory in 2000-2001. Polarized electrons with energies of 1.6, 2.5, 4.2, and 5.7 GeV were scattered from proton targets 15NH3 dynamically polarized along the beam direction) and detected with CLAS. From the measured double spin asymmetries, we extracted virtual photon asymmetries Ap1 and Ap2 and spin structure functions g p1 and gp2 over a wide kinematic range (0.05 GeV2 \u3c Q2 \u3c 5 GeV2 and 1.08 GeV\u3c W \u3c 3 GeV) and calculated moments of gp1. We compare our final results with various theoretical models and expectations, as well as with parametrizations of the world data. Our data, with their precision and dense kinematic coverage, are able to constrain fits of polarized parton distributions, test pQCD predictions for quark polarizations at large x, offer a better understanding of quark-hadron duality, and provide more precise values of higher twist matrix elements in the framework of the operator product expansion
A multi-region assessment of population rates of cardiac catheterization and yield of high-risk coronary artery disease
<p>Abstract</p> <p>Background</p> <p>There is variation in cardiac catheterization utilization across jurisdictions. Previous work from Alberta, Canada, showed no evidence of a plateau in the yield of high-risk disease at cardiac catheterization rates as high as 600 per 100,000 population suggesting that the optimal rate is higher. This work aims 1) To determine if a previously demonstrated linear relationship between the yield of high-risk coronary disease and cardiac catheterization rates persists with contemporary data and 2) to explore whether the linear relationship exists in other jurisdictions.</p> <p>Methods</p> <p>Detailed clinical information on all patients undergoing cardiac catheterization in 3 Canadian provinces was available through the Alberta Provincial Project for Outcomes Assessment in Coronary Heart (APPROACH) disease and partner initiatives in British Columbia and Nova Scotia. Population rates of catheterization and high-risk coronary disease detection for each health region in these three provinces, and age-adjusted rates produced using direct standardization. A mixed effects regression analysis was performed to assess the relationship between catheterization rate and high-risk coronary disease detection.</p> <p>Results</p> <p>In the contemporary Alberta data, we found a linear relationship between the population catheterization rate and the high-risk yield. Although the yield was slightly less in time period 2 (2002-2006) than in time period 1(1995-2001), there was no statistical evidence of a plateau. The linear relationship between catheterization rate and high-risk yield was similarly demonstrated in British Columbia and Nova Scotia and appears to extend, without a plateau in yield, to rates over 800 procedures per 100,000 population.</p> <p>Conclusions</p> <p>Our study demonstrates a consistent finding, over time and across jurisdictions, of linearly increasing detection of high-risk CAD as population rates of cardiac catheterization increase. This internationally-relevant finding can inform country-level planning of invasive cardiac care services.</p
Does Diving Limit Brain Size in Cetaceans?
We test the longstanding hypothesis, known as the dive constraint hypothesis, that the oxygenation demands of diving pose a constraint on aquatic mammal brain size.Using a sample of 23 cetacean species we examine the relationship among six different measures of relative brain size, body size, and maximum diving duration. Unlike previous tests we include body size as a covariate and perform independent contrast analyses to control for phylogeny. We show that diving does not limit brain size in cetaceans and therefore provide no support for the dive constraint hypothesis. Instead, body size is the main predictor of maximum diving duration in cetaceans. Furthermore, our findings show that it is important to conduct robust tests of evolutionary hypotheses by employing a variety of measures of the dependent variable, in this case, relative brain size
Estrogen receptor-α is required for the osteogenic response to mechanical loading in a ligand-independent manner involving its activation function 1 but not 2
Estrogen receptor‐α (ERα) is crucial for the adaptive response of bone to loading but the role of endogenous estradiol (E2) for this response is unclear. To determine in vivo the ligand dependency and relative roles of different ERα domains for the osteogenic response to mechanical loading, gene‐targeted mouse models with (1) a complete ERα inactivation (ERα−/−), (2) specific inactivation of activation function 1 (AF‐1) in ERα (ERαAF‐10), or (3) specific inactivation of ERαAF‐2 (ERαAF‐20) were subjected to axial loading of tibia, in the presence or absence (ovariectomy [ovx]) of endogenous E2. Loading increased the cortical bone area in the tibia mainly as a result of an increased periosteal bone formation rate (BFR) and this osteogenic response was similar in gonadal intact and ovx mice, demonstrating that E2 (ligand) is not required for this response. Female ERα−/− mice displayed a severely reduced osteogenic response to loading with changes in cortical area (−78% ± 15%, p < 0.01) and periosteal BFR (−81% ± 9%, p < 0.01) being significantly lower than in wild‐type (WT) mice. ERαAF‐10 mice also displayed a reduced response to mechanical loading compared with WT mice (cortical area −40% ± 11%, p < 0.05 and periosteal BFR −41% ± 8%, p < 0.01), whereas the periosteal osteogenic response to loading was unaffected in ERαAF‐20 mice. Mechanical loading of transgenic estrogen response element (ERE)‐luciferase reporter mice did not increase luciferase expression in cortical bone, suggesting that the loading response does not involve classical genomic ERE‐mediated pathways. In conclusion, ERα is required for the osteogenic response to mechanical loading in a ligand‐independent manner involving AF‐1 but not AF‐2
First Measurement of Electroproduction off Nuclei in the Current and Target Fragmentation Regions
We report results of hyperon production in semi-inclusive
deep-inelastic scattering off deuterium, carbon, iron, and lead targets
obtained with the CLAS detector and the Continuous Electron Beam Accelerator
Facility 5.014~GeV electron beam. These results represent the first
measurements of the multiplicity ratio and transverse momentum
broadening as a function of the energy fraction~() in the current and target
fragmentation regions. The multiplicity ratio exhibits a strong suppression at
high~~and~an enhancement at~low~. The measured transverse momentum
broadening is an order of magnitude greater than that seen for light mesons.
This indicates that the propagating entity interacts very strongly with the
nuclear medium, which suggests that propagation of diquark configurations in
the nuclear medium takes place at least part of the time, even at high~. The
trends of these results are qualitatively described by the Giessen
Boltzmann-Uehling-Uhlenbeck transport model, particularly for the multiplicity
ratios. These observations will potentially open a new era of studies of the
structure of the nucleon as well as of strange baryons.Comment: 14 pages, 6 figure
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