633 research outputs found
FORTRAN program for computing coordinates of circular-arc, single and tandem, turbine and compressor, blade sections on a plane
Coordinates for circular arc blade section of aircraft high speed compressor gas turbines were computed using FORTRAN 4 program. Aerodynamic configurations studied include single segment airfoils, airfoils with slots, and mutiple segment tandem arranged airfoil
FORTRAN program for computing coordinates of circular arc single and tandem turbomachinery blade sections on a plane
FORTRAN program for computing coordinates of circular arc single and tandem turbomachinery blade sections on plan
Off-design correlation for losses due to part-span dampers on transonic rotors
Experimental data from 10 transonic fan rotors were used to correlate losses created by part-span dampers located near the midchord position on the rotor blades. The design tip speed of these rotors varied from 419 to 425 m/sec, and the design pressure ratio varied from 1.6 to 2.0. Additional loss caused by the dampers for operating conditions between 50 and 100 percent of design speed were correlated with relevant aerodynamic and geometric parameters. The resulting correlation predicts the variation of total-pressure-loss coefficient in the damper region to a good approximation
Microbial Decontamination and Weight of Carcass Beef as Affected by Automated Washing Pressure and Length of Time of Spray
Carcass beef has traditionally been washed by hand to remove foreign material such as hair, soil particles, and microbiological organisms that have contaminated the surfaces. These carcasses are inspected by the Food Safety Inspection Service (FSIS)to detect defects related to carcass cleanliness. Recent research and development of technology have emphasized automated machine washing.
At pressures above that normally used, it is conceivable that water could penetrate tissue surfaces and be absorbed by the carcasses. Also, longer wash periods may enhance water uptake by carcasses. According to the ASH RAE Handbook and Product Directory, the average shrinkage of carcass beef using good current practices was 1.3% at 20 hr postmortem. USDA meat inspection regulations required that carcasses sustain no net increase in weight due to absorption of water during the washing process. There is no available literature on the effects of various automated washing techniques on carcass weights after a 20-hr chill.
The objectives of the study reported presently were to determine the effects of nozzle pressure and length of time washed on the microflora and weights of carcass beef at 20 hr postmortem
Germ Plasm Evaluation Program- Progress Report No. 12
Breed differences in performance characteristics are an important genetic resource for improving efficiency of beef production. Diverse breeds are required to exploit heterosis and complementarity through crossbreeding and to match genetic potential with diverse markets, feed resources and climates. This report presents preliminary results from an ongoing study at the Roman L. Hruska U.S. Meat Animal Research Center to characterize breeds of cattle representing different biological types for traits that influence quantity and value of production.
Experimental Procedure:
The Germ Plasm Evaluation (GPE) program has been conducted in four cycles. Table 1 shows the mating plan for cycles I, II, III, and IV. Each cycle was initiated by mating Hereford and Angus cows by artificial insemination (AI) to sires of diverse breeds. Semen from the same Hereford and Angus bulls has been used throughout to produce control Hereford-Angus (original HAx, sires born 1968-70) reciprocal crosses in each cycle. In cycle IV, new samples of Hereford and Angus (current HAx, sires born 1982-84) bulls were added to evaluate genetic trends within these breeds. In cycle IV, semen from 14 original control Angus, 11 original control Hereford, 30 current Angus, 32 current Hereford (14 horned and 18 polled), 29 Longhorn, 24 Piedmontese, 31 Charolais, 29 Salers, 31 Galloway, 22 Nel1ore, and 26 Shorthorn bulls is being used by AI to produce about 200 calves per sire breed in five calf crops (1986-1990). Following an AI period of about 45 days, one or two bulls each of Angus, Hereford, Charolais, Gelbvieh, and Pinzgauer bulls are used each year by natural service in single-sire breeding pastures for about 21 days. These breeds are being used in clean-up matings to increase ties to previous cycles and facilitate eventual pooling of results over all four cycles
Breeding for Lean Beef (Germ Plasm Evaluation Program)
Historically, when steers were finished on pasture, ability to finish at a young age was desirable, particularly when market requirements for fatness were great. However, ability to fatten became a handicap as we shifted to increased use of concentrate feeds in diets of growing-finishing cattle. Consequently, yield grades were added to the USDA grading system to reflect variation in carcass value associated with differences in yield of retail product. Recently, consumer pressure to reduce caloric and fat content of beef and other red meats has intensified because coronary heart disease is believed to be associated with elevated blood-cholesterol levels. Cholesterol levels are, in turn, associated with dietary intake of saturated fat. Dietary control of the type and amount of fat consumed is strongly recommended by members of the medical profession in an attempt to regulate blood-cholesterol levels. The purpose of this paper is to examine genetic variation among and within breeds in the amount and distribution of fat and lean in beef carcasses and to evaluate opportunities to genetically change fat and caloric content of retail product in cattle
Characteristics of Diverse Breeds in Cycle IV of the Cattle Germ Plasm Evaluation Program at the U.S. Meat Animal Research Center
Breed differences in performance characteristics are an important genetic resource for improving efficiency of beef production. Diverse breeds are required to exploit heterosis and complementarity through crossbreeding and new composite breeds and to match genetic potential with diverse markets, feed resources and climates. This report presents preliminary results from an ongoing study at the Roman L. Hruska U.S. Meat Animal Research Center (MARC) to characterize breeds of cattle representing diverse biological types for traits that influence quantity and value of production
Genetic relationships between sex-specific traits in beef cattle: Mature weight, weight adjusted for body condition score, height and body condition score of cows, and carcass traits of their steer relatives
Data from the first four cycles of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center (USMARC) were used to investigate genetic relationships between mature weight (MW, n = 37,710), mature weight adjusted for body condition score (AMW, n = 37,676), mature height (HT, n = 37,123), and BCS (n = 37,676) from 4- to 8-yr old cows (n = 1,800) and carcass traits (n = 4,027) measured on their crossbred paternal half-sib steers. Covariance components among traits were estimated using REML. Carcass traits were adjusted for age at slaughter. Estimates of heritability for hot carcass weight (HCWT); percentage of retail product; percentage of fat; percentage of bone; longissimus muscle area; fat thickness adjusted visually; estimated kidney, pelvic, and heart fat percentage; marbling score; Warner-Bratzler shear force; and taste panel tenderness measured on steers were moderate to high (0.26 to 0.65), suggesting that selection for carcass and meat traits could be effective. Estimates of heritability for taste panel flavor and taste panel juiciness were low and negligible (0.05 and 0.01, respectively). Estimates of heritability from cow data over all ages and seasons were high for MW, AMW, and HT (0.52, 0.57, 0.71; respectively) and relatively low for BCS (0.16). Pair-wise analyses for each female mature trait with each carcass trait were done with bivariate animal models. Estimates of genetic correlations between cow mature size and carcass composition or meat quality traits, with the exception of HCWT, were relatively low. Selection for cow mature size (weight and/or height) could be effective and would not be expected to result in much, if any, correlated changes in carcass and meat composition traits. However, genetic correlations of cow traits, with the possible exception of BCS, with HCWT may be too large to ignore. Selection for steers with greater HCWT would lead to larger cows
RECOVERY OF FISSION PRODUCTS FROM WASTE SOLUTIONS BY SOLVENT EXTRACTION
Increasing industrial, military, and space requirements for certain fission products place emphasis on large-scale methods for their recovery from waste liquors produced by the fuel recovery processes. With development of organic extractants for separating and recovering these fission products, solvent extraction offers a versatile alternative to ion-exchange, precipitation, and crystallization procedures heretofore used for small-scale recoveries. A process flowsheet was developed for the recovery of strontium and mixed rare earths from adjusted Purex 1WW solution by the use of di(2-ethylhexyl)phosphoric acid (D2EHPA). After adding tartrate t complex the iron and caustic to adjust the pH to 6, strontium and rare earths are co-extracted and then co-stripped with nitric acid in the first cycle. In additional D2EHPA extraction cycles, they are isolated as concentrated fractions. The mixed rare earths from this process can be treated by tributyl phosphate (TBP) extraction to separate the individual rare earth elements of which promethium and cerium are of greatest interest. Zirconium--niobium also may be recovered with D2EHPA from acidic waste liquors. An amine pretreatment extraction process was developed for removing nitric acid, iron sulfate, zirconium-- niobium, and ruthenium from waste solutions to furnish a feed liquor more amenable to subsequent processes for recovering fission products. The separate recovery of ruthenium, zirconium-- niobium, and rare earths may also be possible by amine extraction. A process based on the use of substituted phenols was developed for recovering cesium from alkaline waste solutions. These compounds are selective extractants for cesium, giving high decontamination from other fission products and sodium, and they are readily stripped with dilute nitric acid. Previous studies also outlined methods for recovering neptunium, plutonium, and technetium with solvents similar to those described. When appropriately cornbined, these developments offer a versatile integrated solvent extraction flowsheet for the recovery of all important fission products and other components from waste liquors. (auth
Changes in PPARδ Protein Content following Acute Aerobic Exercise in Human Vastus Lateralis Muscle.
PPARδ is a transcription factor which functions in the regulation of lipid and glucose metabolism, and may be implicated as a therapeutic target for several metabolic diseases. Exercise training has previously been shown to increase PPARδ protein content, but the response of PPARδ to acute exercise is not yet understood. PURPOSE: To explore changes in PPARδ protein content following an acute bout of aerobic exercise in untrained obese adults. METHODS: 8 men and 4 women participated in the study. Subjects’ mean age, weight, VO2MAX (Bruce treadmill GXT), and body composition (DEXA) were 44 yr, 93.2 kg, 28.2 mL/kg/min, and 40.5% body fat, respectively. Subjects were asked to refrain from exercise for 1 week prior to the experiment and to maintain normal dietary habits during the study. Muscle biopsies were obtained from the vastus lateralis 3 days prior to acute exercise and again 24 hours after exercise. Subjects were exercised on a motorized treadmill at 70% VO2MAX for a target duration of 400kcal energy expenditure during the exercise session. PPARδ protein content in biopsied tissue was determined by Western blot analysis. Data were analyzed by repeated measures ANOVA and expressed as means ± standard error. RESULTS: PPARδ content was enhanced 24 hours following acute exercise in previously untrained, obese adults (unexercised 1.54±0.38 vs. exercised 2.30±0.39 arbitrary units, P\u3c0.05). Gel mobility shift indicated no difference in activity of PPARδ (phosphorylated: total) following exercise (unexercised 0.36±0.03 vs. exercised 0.34±0.04). CONCLUSION: Our study shows that PPARδ expression is enhanced in untrained, obese adults following a single bout of aerobic exercise with no relative change in phosphorylation of PPARδ. These data indicate that acute exercise plays a role in the expression of PPARδ. Funding for this research was provided by HydroWorx International, Inc., the Sydney & J.L. Huffines Institute for Sports Medicine and Human Performance at Texas A&M University and The Texas Chapter of The American College of Sports Medicin
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