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91.
This study shows that sockets can be reliable enough in a relatively benign environment for the short-term. Criteria for failure-free performance include 1) operation in a controlled, non-vibration environment, 2) gold-plated, machined sockets, 3) either gold or tin-plated IC leads. Accelerated testing is required to estimate long-term reliability. Numerous federal and commercial systems use socketed integrated circuits (ICs) satisfactorily. Maintainability of circuit boards, ease of equipment upgrading, and simplifying transition from development to production are some of the advantages of sockets.  相似文献   
92.
In this work, we describe and implement an electrokinetic approach for single-nucleotide polymorphism (SNP) discrimination using a PDMS/glass-based microfluidic chip. The technique takes advantage of precise control of the coupled thermal (Joule heating), shear (electroosmosis), and electrical (electrophoresis) energies present at an array of probes afforded by the application of external electrical potentials. Temperature controllers and embedded thermal devices are not required. The chips can be easily and inexpensively fabricated using standard microarray printing methods combined with soft-lithography patterned PDMS fluidics, making these systems easily adaptable to applications using higher density arrays. Extensive numerical simulations of the coupled flow and thermal properties and microscale thermometry experiments are described and used to characterize the in-channel conditions. It was found that optimal conditions for SNP detection occur at a lower temperature on-chip than for typical microarray experiments, thereby revealing the importance of the electrical and shear forces to the overall process. To demonstrate the clinical utility of the technique, the detection of single-base pair mutations in the survival motor neuron gene, associated with the childhood disease spinal muscular atrophy, is conducted.  相似文献   
93.
The formation of androgen-binding protein (ABP) by cultured Sertoli cells, prepared from testes of immature rats, is increased when androgens or follicle-stimulating hormone (FSH) are present in the medium. Testosterone and 5alpha-dihydrotestosterone are equally effective in stimulating the synthesis and secretion of ABP, but non-androgenic steroids examined (progesterone, 17beta-estradiol and corticosterone) are without influence. Maximal increases are observed when androgens are added at the time of cell plating. Cells maintained in culture medium devoid of hormones become progressively less sensitive to subsequent addition of testosterone or FSH. Data are discussed in relation to the sites of androgen requirements for spermatogenesis.  相似文献   
94.
Used as source of data the MMPI protocols of 223 18-60 yr old psychiatric inpatients randomly divided into 2 groups for a double cross-validation design, clinical diagnosis of depressive vs nondepressive states as criterion, and multiple regression as the main analytic technique. The individual validity of MMPI scales constructed through empirical (external criterion), purely intuitive, and intuitive plus internal consistency techniques was lower than the validity of regression models. The validity and cross-validity of regression equations obtained from several different sets of scales including "linear models" composed of single scales and "configural models" that included their binary cross-products was very similar across models and across construction techniques of the component scales. A simplified regression formula is provided for diagnostic purposes. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
Placing major pieces of electrical equipment in service is aided by a systematic approach to selection, specification, inspection, shipment, storage, check-out, and run-in. This paper describes the detailed planning that helped assure a successful start-up of a large electrical motor. Although a specific installation is described, it will be found that many of the procedures will be generally applicable.  相似文献   
96.
Comment on article in the April 1961 "American Psychologist". It is in response to the account of the tripartite American Board of Clinical Hypnosis and its certification of physicians, dentists, and psychologists through three sub-boards. The authors consider it their duty to call attention to the fact that there exists a strong body of opinion which is opposed to the formation of such examining and certifying boards. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
The estimation of Holstein heifer body weight (BW) from heart girth measurements is needed, as many farms do not have animal scales to make the management decisions that require BW. The correlation between heart girth and BW is known to vary with differing animal conformation. The previous equation to correlate the 2 measures for Holstein dairy heifers was done 25 yr ago. Data were derived from 6 US experiment stations that are part of Regional Research Project NC-2042: Management Systems to Improve the Economic and Environmental Sustainability of Dairy Enterprises. After deriving a new equation from a data set of observations and using a second validation data set, it was determined that the equation developed in 1992 was still valid and further equation development was not needed at this time.  相似文献   
98.
The objective of these experiments was to compare 4 total mixed rations fed to USDA-certified organic dairy cows in New England. Forty-eight Jersey cows from the University of New Hampshire (UNH) and 64 Holstein cows from the University of Maine (UMaine) were assigned to a 2 × 2 factorial arrangement of treatments testing the main effects of corn silage versus grass silage as the forage base and commodity concentrates versus a complete pelleted concentrate mixture. Treatment diets were fed as a total mixed ration for 8 wk during the winter and spring months of 2007, 2008, and 2009. Milk yield, component, and quality data were recorded and used to calculate the value of the milk produced for each cow. The dry matter intake (DMI) was recorded and used to calculate the average cost per cow per day of each diet. Income over feed costs were calculated for each diet using milk value and feed cost data. Feed cost and income over feed cost data were resampled using bootstrap methodology to examine potential patterns. Milk yield, milk fat and true protein concentrations, and SCC were similar among treatments. Cows at UNH fed corn silage tended to have higher DMI and lower milk urea nitrogen than did cows fed grass silage, whereas cows fed pellets had higher DMI than cows fed commodities. Cows at UNH fed commodities tended to have higher body condition scores than those fed pellets. Cows at UMaine fed commodities tended to have higher DMI than did cows fed pellets, and cows fed corn silage had lower milk urea nitrogen than did cows fed grass silage. Body weights and body condition scores were not different for cows at UMaine. Feed costs were significantly higher for corn silage diets and diets at UNH containing pellets, but not at UMaine. The calculated value of the milk and income over feed costs did not differ among treatments at either university. Bootstrap replications indicated that the corn silage with commodities diet generally had the highest feed cost at both UNH and UMaine, whereas grass silage diets containing commodities generally had the lowest cost. In contrast, the grass silage with commodities diets had the highest income over feed cost in the majority of the replications at both UNH and UMaine replications, whereas the corn silage with commodities diets had the lowest rank. Similar results were observed when forage prices were increased or decreased by 5, 10, and 25% above or below the actual feed price. Feeding a grass silage-based diet supplemented with commodity concentrates may have an economic advantage for dairy producers in New England operating under an organic system of production.  相似文献   
99.
ABSTRACT: Vitamin E, thiamin, riboflavin, niacin, vitamin B6, and vitamin B12 concentrations of flat iron steaks and petite tenders from steers fed finishing rations containing 0% and 40% corn wet distiller's grains and solubles (WDGS) with and without supplemental vitamin E were determined. Feeding treatment groups were: 0% WDGS with basal vitamin E, 0% WDGS with supplemental vitamin E (500 IU daily), 40% WDGS with basal vitamin E, and 40% WDGS and supplemental vitamin E. Cattle can be fed 40% WDGS diets more economically than corn diets. The incorporation of 40% WDGS, with and without vitamin E, was hypothesized to have little effect on the vitamin concentrations of these value meat cuts. Flat iron steaks and petite tenders were broiled and/or grilled to 70 °C internal temperature. Mean cooking yields ranged from 68.7% to 78.2%. The majority of the vitamin concentrations of broiled and of grilled meat were significantly different (P < 0.05) from that of raw meat. Vitamin E concentrations of raw and cooked meat from steers that received supplemental vitamin E were significantly higher (P < 0.05) than those fed basal vitamin E. Significant differences in thiamin, riboflavin, vitamin B6, and vitamin B12 concentrations in raw flat iron steaks and in vitamin B6 in raw petite tenders were observed by WDGS. Thiamin, vitamin B6, and vitamin B12 concentrations of broiled flat iron steaks were significantly different (P < 0.05) than grilled. A few differences in vitamin concentrations of the flat iron steaks and petite tenders were observed by WDGS, vitamin E supplementation, and cooking treatments, but most of the vitamin concentrations were statistically similar.  相似文献   
100.
Environmental pests may serve as reservoirs and vectors of zoonotic pathogens to leafy greens; however, it is unknown whether insect pests feeding on plant tissues could redistribute these pathogens present on the surface of leaves to internal sites. This study sought to differentiate the degree of tissue internalization of Escherichia coli O157:H7 when applied at different populations on the surface of lettuce and spinach leaves, and to ascertain whether lettuce-infesting insects or physical injury could influence the fate of either surface or internalized populations of this enteric pathogen. No internalization of E. coli O157:H7 occurred when lettuce leaves were inoculated with 4.4 log CFU per leaf, but it did occur when inoculated with 6.4 log CFU per leaf. Internalization was statistically greater when spinach leaves were inoculated on the abaxial (underside) than when inoculated on the adaxial (topside) side, and when the enteric pathogen was spread after surface inoculation. Brief exposure (~18 h) of lettuce leaves to insects (5 cabbage loopers, 10 thrips, or 10 aphids) prior to inoculation with E. coli O157:H7 resulted in significantly reduced internalized populations of the pathogen within these leaves after approximately 2 weeks, as compared with leaves not exposed to insects. Surface-contaminated leaves physically injured through file abrasions also had significantly reduced populations of both total and internalized E. coli O157:H7 as compared with nonabraded leaves 2 weeks after pathogen exposure.  相似文献   
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