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71.
The resistance to abrasion is tested by grinding a groove in the surface of the refractory by means of a carborundum wheel with suitable mounting. Other methods used in the tests are discussed. Factors affecting resistance of silica brick to abrasion are porosity and degree of burn. Porosity is affected by grind, quality of ganister, per cent lime and workmanship. Data are given showing a rough relation between length of groove, porosity and burn.  相似文献   
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The authors discuss the advantages and limitations of computers in psychological assessment in terms of (a) the need to validate computer-based test interpretation systems; (b) the impact of computerization on psychometric properties of instruments; (c) the potential innovative uses of computers; (d) acceptance of computers by staff and clients; and (e) professional concerns regarding standards, accountability, and reimbursement. It is concluded that it is time for psychology to develop standards and policies for the professional and responsible use of computers in psychological assessments. (75 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Selenium injections and oral vitamin E supplementation prepartum were related to: postpartum uterine involution (decrease in uterine size per unit time) and days to minimum uterine size in a 2 X 2 factorial design. Complete data were analyzed from 64 cows. Groups were selenium plus vitamin E, vitamin E, selenium, and control. Factors significantly affecting uterine size between 14 and 50 d postpartum were cow weight, days postpartum-linear, days postpartum-quadratic, day X metritis, and day X metritis X selenium treatment. Days to minimum uterine size were significantly less in cows with metritis and selenium treated when compared with cows with metritis and not selenium treated (32.9 vs. 35.8).  相似文献   
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This paper describes a program in place at Ontario Hydro where risk models are being developed for all its nuclear generating stations and where the results of these risk models and their constituent system reliability models are being used in the operational reliability program for the stations involved. Furthermore, the results of the station operational reliability monitoring program are being utilized to keep the system reliability and station risk models up to date.The program in place for the Darlington Nuclear Generating Station is examined in detail to illustrate Ontario Hydro's approach.  相似文献   
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IAPs comprise a family of inhibitors of apoptosis found in viruses and animals. In vivo binding studies demonstrated that both baculovirus and Drosophila IAPs physically interact with an apoptosis-inducing protein of Drosophila, Reaper (RPR), through their baculovirus IAP repeat (BIR) region. Expression of IAPs blocked RPR-induced apoptosis and resulted in the accumulation of RPR in punctate perinuclear locations which coincided with IAP localization. When expressed alone, RPR rapidly disappeared from the cells undergoing RPR-induced apoptosis. Expression of P35, a caspase inhibitor, also blocked RPR-induced apoptosis and delayed RPR decline, but RPR remained cytoplasmic in its location. Mutational analysis of RPR demonstrated that caspases were not directly responsible for RPR disappearance. The physical interaction of IAPs with RPR provides a molecular mechanism for IAP inhibition of RPR's apoptotic activity.  相似文献   
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Numerous creatine formulations have been developed primarily to maximize creatine absorption. Creatine ethyl ester is alleged to increase creatine bio-availability. This study examined how a seven-week supplementation regimen combined with resistance training affected body composition, muscle mass, muscle strength and power, serum and muscle creatine levels, and serum creatinine levels in 30 non-resistance-trained males. In a double-blind manner, participants were randomly assigned to a maltodextrose placebo (PLA), creatine monohydrate (CRT), or creatine ethyl ester (CEE) group. The supplements were orally ingested at a dose of 0.30 g/kg fat-free body mass (approximately 20 g/day) for five days followed by ingestion at 0.075 g/kg fat free mass (approximately 5 g/day) for 42 days. Results showed significantly higher serum creatine concentrations in PLA (p = 0.007) and CRT (p = 0.005) compared to CEE. Serum creatinine was greater in CEE compared to the PLA (p = 0.001) and CRT (p = 0.001) and increased at days 6, 27, and 48. Total muscle creatine content was significantly higher in CRT (p = 0.026) and CEE (p = 0.041) compared to PLA, with no differences between CRT and CEE. Significant changes over time were observed for body composition, body water, muscle strength and power variables, but no significant differences were observed between groups. In conclusion, when compared to creatine monohydrate, creatine ethyl ester was not as effective at increasing serum and muscle creatine levels or in improving body composition, muscle mass, strength, and power. Therefore, the improvements in these variables can most likely be attributed to the training protocol itself, rather than the supplementation regimen.  相似文献   
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We present the main design features for the GISMO-2 bolometer camera, which we build for background-limited operation at the IRAM 30 m telescope on Pico Veleta, Spain. GISMO-2 will operate simultaneously in the 1 and 2 mm atmospherical windows. The 1 mm channel uses a \(32 \times 40\) TES-based backshort under grid (BUG) bolometer array, the 2 mm channel operates with a \(16 \times 16\) BUG array. The camera utilizes almost the entire full field of view provided by the telescope. The optical design of GISMO-2 was strongly influenced by our experience with the GISMO 2 mm bolometer camera, which is successfully operating at the 30 m telescope. GISMO is accessible to the astronomical community through the regular IRAM call for proposals.  相似文献   
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