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91.
C E Coppock J W West J R Moya D H Nave J M LaBore K G Thompson L D Rowe C E Gates 《Journal of dairy science》1985,68(9):2248-2258
In Experiment 1, 27 lactating cows were fed complete rations ad libitum of 0, 15, and 30% whole cottonseed to examine the effects on intake, digestibility, blood gases, and blood metabolites. Dry matter intake declined linearly with increased cottonseed, but because of greater energy density, calculated net energy for lactation intake was not depressed significantly. Ether extract, crude protein, and calcium digestibility increased with cottonseed in the diet. Respiration rates declined with dry matter intake and increased cottonseed feeding; some blood gases were influenced by cottonseed feeding but not in a detrimental way. No data among 13 blood metabolites indicated effects of gossypol toxicity with 30% whole cottonseed in the diet. In Experiment 2, 24 dry, nonpregnant Holstein cows were offered complete rations ad libitum of 15, 35, and 55% whole cottonseed to measure responses in intake, respiration rates, and blood metabolites. The highest cottonseed diet significantly depressed intake of both dry matter and calculated net energy for lactation. Maximum dry matter from cottonseed eaten by an individual was 8.4 kg/d (average for 1 wk). Respiration rates declined parallel to intake. No evidence for gossypol toxicity was seen among data of 11 metabolites in blood. 相似文献
92.
Crocker Jennifer; Thompson Leigh L.; McGraw Kathleen M.; Ingerman Cindy 《Canadian Metallurgical Quarterly》1987,52(5):907
In two studies, we explored the effects of trait self-esteem and threats to the self-concept on evaluations of others. In Study 1, subjects high, moderate, and low in self-esteem received either success, failure, or no feedback on a test and later evaluated three pairs of targets: ingroups and outgroups based on a minimal intergroup manipulation, those who scored above average and those who scored below average on the test, and themselves and the average college student. Study 2 explored the effects of self-esteem and threat on ingroup favoritism in a real-world setting, campus sororities. Together, the results of these studies indicate that individuals high in self-esteem, but not those low in self-esteem, respond to threats to the self-concept by derogating outgroups relative to the ingroup when the group boundaries have evaluative implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
The operating speed and endpoint positional accuracy of existing industrial manipulators are limited by the inertial and stiffness characteristics of the articulating members of the robot's mechanical linkage. This limitation may be overcome by developing members having high structural stiffness and strength with low mass, and this has been recognized for some time. These characteristics can be obtained by fabricating the moving members of manipulators in fiber reinforced composite materials. In order to establish a basis for the dynamic analysis of robots fabricated in viscoelastic composites, a variational theorem is developed herein. A preliminary comparative study is then undertaken for manipulators manufactured in a graphite-epoxy composite material and also steel in order to demonstrate some of the advantages to be accrued from this proposed new design philosophy. 相似文献
94.
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96.
The cytoskeletal components of hamster oocytes, zygotes, and spontaneously activated parthogenotes were examined after immunocytochemical labeling. Microtubules were found only in the anastral, tangentially arranged second meiotic spindle of unfertilized oocytes. Taxol treatment of unfertilized oocytes greatly augmented astral microtubules in both the metaphase II spindle and the cortex. Disruption of the meiotic spindle microtubules with nocodazole resulted in cortical chromosomal scattering. During hamster sperm incorporation and pronuclear formation, no sperm aster was detected in association with the male DNA. Instead, a large overlapping array of microtubules assembled in the cortex. By mitosis, this interphase array disassembled and an anastral metaphase spindle formed. Microtubule and chromatin configurations were also imaged in hamster oocytes injected with human sperm. Astral microtubules were absent from the sperm centrosome. The implications of these results are discussed in relation to the hamster oocyte penetration assay, a test commonly used by in vitro fertilization clinics to demonstrate the fertilizing ability of human sperm. We conclude that since hamsters and humans follow different methods of centrosome inheritance, maternal and paternal, respectively, the hamster may be an inappropriate model for exploring microtubule and centrosomal defects in humans or for assaying postinsemination forms of human male fertility defects. 相似文献
97.
The absolute right to refuse medical treatment, even if the reasons are irrational, is confined to competent adults. Children under 16 years can give legal consent to treatment in the absence of consent from those with parental responsibility. Children under 18 years do not, however, have an absolute right to consent, or refuse to consent, to treatment. The views of children assume increasing importance with age and maturity. Accident and emergency medical and nursing staff may face difficult decisions when children, or those with parental responsibility, refuse to consent to medical treatment. This paper presents guidelines designed to guide the decision making process in immediately or potentially life threatening conditions and in non-life-threatening conditions. 相似文献
98.
P. T. Thompson R. Silk A. Herridge 《International Journal of Satellite Communications and Networking》1992,10(4):183-198
Developed primarily to provide continuation of services from the INTELSAT V satellites in the Pacific Ocean Region, this latest generation of satellites also has utility for operation in other roles. Several new technologies are combined to give cost-effective international satellite communications on a global, regional and domestic basis. This new higher power satellite will form a fundamental part of the INTELSAT global network, having been designed to match the projected traffic demands and future service requirements. 相似文献
99.
The influence of convective heat transfer on constant current density anodizing of aluminium in sulfuric acid has been examined in a wall-jet electrode reactor. The uniformity of the anodic film thickness is related to the local electrode temperature distribution, which is dependent on the convection. The higher the local temperature, the greater the local oxide thickness. An increased local temperature enhances local field assisted oxide dissolution at the pore bases, and consequently acts to increase the local current density. At relatively high current densities, local features develop on the electrode surface, accompanied by high initial, local temperature rises. The relevance of such local features, limiting useful oxide growth, is considered further. 相似文献
100.
Thompson Robert J.; Gil Karen M.; Keith Barbara R.; Gustafson Kathryn E.; George Linda K.; Kinney Thomas R. 《Canadian Metallurgical Quarterly》1994,62(4):856
Rates of poor psychological adjustment of children with sickle cell disease remained relatively constant over initial and follow-up assessment points. 50 children (aged 7–12 yrs) and their mothers completed the initial protocol. 30 children completed the follow-up plus 5 additional children and their mothers. These Ss were aged 7–24 yrs at follow-up. With initial levels of adjustment controlled, children's strategies for coping with pain accounted for a significant increment in child-reported symptoms and mother-reported internalizing behavior problems at follow-up beyond the contribution of illness and demographic parameters and follow-up interval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献