5,285 research outputs found
Effects of Elevated H\u3csup\u3e+\u3c/sup\u3e And P\u3csub\u3ei\u3c/sub\u3e on The Contractile Mechanics of Skeletal Muscle Fibres From Young and Old Men: Implications for Muscle Fatigue in Humans
The present study aimed to identify the mechanisms responsible for the loss in muscle power and increased fatigability with ageing by integrating measures of wholeâmuscle function with single fibre contractile mechanics. After adjusting for the 22% smaller muscle mass in old (73â89 years, n = 6) compared to young men (20â29 years, n = 6), isometric torque and power output of the knee extensors were, respectively, 38% and 53% lower with age. Fatigability was âź2.7âfold greater with age and strongly associated with reductions in the electricallyâevoked contractile properties. To test whether crossâbridge mechanisms could explain ageârelated decrements in knee extensor function, we exposed myofibres (n = 254) from the vastus lateralis to conditions mimicking quiescent muscle and fatiguing levels of acidosis (H+) (pH 6.2) and inorganic phosphate (Pi) (30 mm). The fatigueâmimicking condition caused marked reductions in force, shortening velocity and power and inhibited the lowâ to highâforce state of the crossâbridge cycle, confirming findings from nonâhuman studies that these ions act synergistically to impair crossâbridge function. Other than severe ageârelated atrophy of fast fibres (â55%), contractile function and the depressive effects of the fatigueâmimicking condition did not differ in fibres from young and old men. The selective loss of fast myosin heavy chain II muscle was strongly associated with the ageârelated decrease in isometric torque (r = 0.785) and power (r = 0.861). These data suggest that the ageârelated loss in muscle strength and power are primarily determined by the atrophy of fast fibres, but the ageârelated increased fatigability cannot be explained by an increased sensitivity of the crossâbridge to H+ and Pi
On the nonlocal viscosity kernel of mixtures
In this report we investigate the multiscale hydrodynamical response of a
liquid as a function of mixture composition. This is done via a series of
molecular dynamics simulations where the wave vector dependent viscosity kernel
is computed for three mixtures each with 7-15 different compositions. We
observe that the nonlocal viscosity kernel is dependent on composition for
simple atomic mixtures for all the wave vectors studied here, however, for a
model polymer melt mixture the kernel is independent of composition for large
wave vectors. The deviation from ideal mixing is also studied. Here it is shown
that a Lennard-Jones mixture follows the ideal mixing rule surprisingly well
for a large range of wave vectors, whereas for both the Kob-Andersen mixture
and the polymer melt large deviations are found. Furthermore, for the polymer
melt the deviation is wave vector dependent such that there exists a critical
length scale at which the ideal mixing goes from under-estimating to
over-estimating the viscosity
Cost of inpatient rehabilitation care in the Department of Veterans Affairs
AbstractâWe investigated the determinants of inpatient rehabilitation costs in the Department of Veterans Affairs (VA) and examined the relationship between length of stay (LOS) and discharge costs using data from VA and community rehabilitation hospitals. We estimated regression models to identify patient characteristics associated with specialized inpatient rehabilitation costs. VA data included 3,535 patients discharged from 63 facilities in fiscal year 2001. We compared VA costs to community rehabilitation hospitals using a sample from the Uniform Data System for Medical Rehabilitation of 190,112 patients discharged in 1999 from 697 facilities. LOS was a strong predictor of cost for VA and non-VA hospitals. Functional status, measured by Functional Independence Measure (FIM) scores at admission, was statistically significant but added little explanatory value after controlling for LOS. Although FIM scores were associated with LOS, FIM scores accounted for little variance in cost after controlling for LOS. These results are most applicable to researchers conducting cost-effectiveness analyses.average costs, billing, charges, cost, health economics, micro-cost methods, reimbursement, rehabilitation, VA, veterans
Classification and Management of Upland, Riparian, and Wetland Sites of USDI Bureau of Land Managementâs Miles City Field Office, Eastern Montana USA
A system is presented for the classification and management of uplands, riparian, and wetland sites within the USDI Bureau of Land Managementâs Miles City Field Office in eastern Montana. The Miles City Field of the USDI Bureau of Land Management lies within the northern Great Plains and occupies approximately the eastern 1/3 of Montana. The concepts and terminology used in this document are consistent with usage proposed by Daubenmire (1952, 1968, 1978), and are used in numerous other vegetation-based ecological site classifications for North America. A dichotomous key utilizing indicator plant species is provided for field identification of the habitat types and major seral plant communities (for example community types) that are stable for time frames relevant to land management decisions. The habitat types (for example ecological site types) are identified first in the key. If this is not possible, the key then identifies the major seral community types. Within the description of each community type is a discussion of possible habitat types for the site. Each âtypeâ includes detailed information for managing a particular site. The work utilized 1,126 sample plots resulting in a total of 96 different plant communities identified to either the habitat type (and phase) or community type level. There were 62 identified riparian/wetland types and 28 upland types. In addition, six types are types that can occur in both riparian/wetland and upland situations. There were a total of 663 unique species recorded for the 1,126 sampled stands. Of the 663 species, 551 (83 percent) were native, and 112 (17 percent) were introduced or contain an introduced element. The document can be downloaded from www.ecologicalsolutionsgroup.com
Agricultural Water Management in the Missippi Delta Region of Arkansas
Agriculture is the largest use of soil and water resources in eastern Arkansas. This bulletin summarized the recent historical use of soil and water by agriculture and the impact of irrigation on yields of rice, soybeans and cotton. The experiments conducted in the field to quantitatively schedule irrigations of crops are summarized. The results show the close relationship between the irrigation of crops and the extraction of water from the Alluvial Aquifer. The implications of this relationaship for the future are discussed
The Ursinus Weekly, October 27, 1947
Thespians to stage New York success ⢠Sophs plan dances, class doggie roast ⢠Gen. Arnold makes demand for greater accent on sciences in college curricula ⢠AVC appoints leaders; starts campus clean-up ⢠Ye good olde days in prospect again as school spirit re-appears on campus ⢠Legal society fetes new members; Vice-president Helfferich speaks ⢠May queen to be selected early this semester, Nov. 6 ⢠Gym construction near end; plans for interior finished ⢠Beardwood chemical group elects Pfeiffer president ⢠Reporters added to staff; Lois Cain new sports assistant ⢠Y commission slate opens with discussions, address ⢠New Spanish Club elects officers ⢠Dorms vote to fill WSGA berths ⢠Pre-meds to hear psychiatrist ⢠Aid for Europe? ⢠Grizzlies to play host to victory-hungry PMC ⢠Soccer team bows to Rutgers \u2711\u27, 6-2 ⢠Three teams tied for first in campus football league ⢠Swarthmore interception sets up tally; first frame score gives Garnet 7-0 win ⢠JV hockey team tops Moravian ⢠JV booters thump Hill School ⢠Snell\u27s belles win third straight, 6-1 ⢠Dr. Child addresses English Club ⢠German Club organizes for 1947 ⢠French Club plans activities ⢠New FTA members to be inductedhttps://digitalcommons.ursinus.edu/weekly/1624/thumbnail.jp
Probability estimates for the unique childhood leukemia cluster in Fallon, Nevada, and risks near other U.S. Military aviation facilities.
A unique cluster of childhood leukemia has recently occurred around the city of Fallon in Churchill County, Nevada. From 1999 to 2001, 11 cases were diagnosed in this county of 23,982 people. Exposures related to a nearby naval air station such as jet fuel or an infectious agent carried by naval aviators have been hypothesized as potential causes. The possibility that the cluster could be attributed to chance was also considered. We used data from the Surveillance, Epidemiology, and End Results Program (SEER) to examine the likelihood that chance could explain this cluster. We also used SEER and California Cancer Registry data to evaluate rates of childhood leukemia in other U.S. counties with military aviation facilities. The age-standardized rate ratio (RR) in Churchill County was 12.0 [95% confidence interval (CI), 6.0-21.4; p = 4.3 times symbol 10(-9)]. A cluster of this magnitude would be expected to occur in the United States by chance about once every 22,000 years. The age-standardized RR for the five cases diagnosed after the cluster was first reported was 11.2 (95% CI, 3.6-26.3). In contrast, the incidence rate was not increased in all other U.S. counties with military aviation bases (RR = 1.04; 95% CI, 0.97-1.12) or in the subset of rural counties with military aviation bases (RR = 0.72; 95% CI, 0.48-1.08). These findings suggest that the Churchill County cluster was unlikely due to chance, but no general increase in childhood leukemia was found in other U.S. counties with military aviation bases
The Ursinus Weekly, October 13, 1947
Bears chalk up second straight win, defeat Haverford 6-0: Blydenburg takes pass for touchdown; Gridders maintain unscored-upon pace ⢠General Arnold visits Ursinus for Founders\u27 Day ceremony ⢠Leroy Grayson heads new inter-frat council ⢠Nite game bus tickets available ⢠Swarthmore man guest at AVC meeting tonite ⢠Indian will address forum, Y, on relief ⢠Annex student directs new campus orchestra ⢠Dance and pep rally boost morale on eve before game ⢠Curtain Club holds reception; New members admitted to ranks ⢠Beaver students in food-saving plan similar to Ursinus\u27 ⢠Philosophy student discovers panacea for all problems after two-week study ⢠Hohlfeld to discuss problems of education in British Guiana ⢠Campus briefs: Recorded concerts; Zeta Chi meeting; Inter-frat Council ⢠Annex-dotes ⢠Alumni-society notes ⢠Radium expert enlivens address with experiments, illustrations ⢠Bears to face heavy Moravian 11 Friday ⢠Soccer team bows to Lafayette, 4-1, in opening contest ⢠Campus football resumes, Luther Wilt heads league ⢠Bearettes win practice match ⢠Brotherhood to lead services ⢠Player of the week ⢠Speakers obtained by pre-legal group ⢠Debates start next month ⢠Former Army nurse returns to campus after extensive service in Europe, Asia ⢠Betsy Greene heads English Clubhttps://digitalcommons.ursinus.edu/weekly/3123/thumbnail.jp
Application of Transmission Line Models to Backpanel Plated Through-Hole Via Design
This paper introduces an approach of using a plated through-hole (PTH) via transmission-line model in the design of a thick printed circuit board, such as a backpanel. Full wave FEM modeling of a section of backpanel containing a differential via pair was compared with a transmission model. Computed values of the differential transmission loss agreed within an acceptable range for engineering studies, yet the transmission line model results required less than 2% of the computation time that the full wave model required. Effects of via spacing, via diameter and trace thickness were also examined
Structure and activity of DmmA, a marine haloalkane dehalogenase
DmmA is a haloalkane dehalogenase (HLD) identified and characterized from the metagenomic DNA of a marine microbial consortium. Dehalogenase activity was detected with 1,3âdibromopropane as substrate, with steadyâstate kinetic parameters typical of HLDs ( K m = 0.24 Âą 0.05 mM, k cat = 2.4 Âą 0.1 s â1 ). The 2.2âĂ
crystal structure of DmmA revealed a fold and active site similar to other HLDs, but with a substantially larger active site binding pocket, suggestive of an ability to act on bulky substrates. This enhanced cavity was shown to accept a range of linear and cyclic substrates, suggesting that DmmA will contribute to the expanding industrial applications of HLDs. PDB Code(s): 3U1TPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90241/1/PRO_2009_sm_suppinfo.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/90241/2/2009_ftp.pd
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