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Six hooded crows (Corvus cornix) were trained in alternative simultaneous matching-to-sample and oddity-from-sample tasks with visual stimuli. Bird's ability to acquire the abstract same/different concept was investigated. For this purpose three stimulus sets of the following categories were used: color (black and white cards), shape (Arabic numerals "1" and "2"), and numerousness (heterogeneous arrays of 1 or 2 elements). These three sets were used for training successively and repeatedly; each time the stimulus set was changed for the next one after the criterion (80% correct or better over 30 successive trials) was reached with the previous one. The training procedure was repeated until the criterion could be reached for each of the three stimulus sets within the initial 30-50 trials. After that, the abstractness of the rule acquired by birds was tested. First, the "partial" transfer tests were conducted, which consisted in presentation of novel stimuli with familiar ones (numerals and arrays in the range from 1 to 4). At the final stage, only sets of novel numerals and arrays in the range from 5 to 8 were presented. The crows demonstrated successful transfer in all of these tests, including the test with absolutely novel stimuli (in the first 24 presentations: min 75.0%, p < 0.02; max 83.3%, p < 0.01). The level of correct choices did not differ from the baseline (p > 0.05). This allows us to conclude that birds are capable for formation of the abstract same/different concept. 相似文献
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RIa Vovin IIa Gurovich OF Eryshev SG Za?tsev AIu Magalif 《Canadian Metallurgical Quarterly》1977,77(5):743-749
The authors studied the effectiveness of out-patient treatment by Moditen-Deppt of 128 schizophrenic patients. A comparison of the previous remissions appearing during usual pharmacotherapy and remissions seen during Moditen-Depot treatment depicted statistically significant differences, indicating a distinct prevention of exacerbations due to this preparation, an increase in the duration and improved quality of remissions. Such improved remissions were expressed in lesser severity, in a decrease of psychopathological disturbances, changes qualified as a "mollification of a defect" and an improvement of some socio-clinical indices. 相似文献
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外流降膜板式蒸发器作为替代列管式蒸发器的新设备应用于氧化铝行业,其板片材质处于一个摸索选择的过程。本文就高合金不锈钢板片的失败事例进行分析,通过试验、试用,最终找到较为理想的材质。 相似文献
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针对德兴铜矿设备状态监测的实际情况,论述了矿山设备润滑磨损状态监测系统,利用VB语言结合SQL Senrer开发设备润滑磨损状态分析系统。 相似文献
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I Dalsgaard BK Gudmundsdóttir S Helgason S H?ie OF Thoresen UP Wichardt T Wiklund 《Canadian Metallurgical Quarterly》1998,84(6):999-1006
Estrogen therapy increases plasma HDL levels, which may reduce cardiovascular risk in postmenopausal women. The mechanism of action of estrogen in influencing various steps in hepatic HDL and apolipoprotein (apo) A-I synthesis and secretion are not fully understood. In this study, we have used the human hepatoblastoma cell line (Hep G2) as an in vitro model system to delineate the effect of estradiol on multiple regulatory steps involved in hepatic HDL metabolism. Incubation of Hep G2 cells with estradiol resulted in the following statistically significant findings: (1) increased accumulation of apoA-I in the medium without affecting uptake/removal of radiolabeled HDL-protein; (2) accelerated incorporation of [3H]leucine into apoA-I; (3) selective increase in [3H]leucine incorporation into lipoprotein (LP) A-I but not LP A-I+A-II HDL particles (HDL particles without and with apoA-II, respectively); (4) increased ability of apoA-I-containing particles to efflux cholesterol from fibroblasts; (5) stimulated steady state apoA-I but not apoA-II mRNA expression; and (6) increased newly transcribed apoA-I mRNA message without effect on apoA-I mRNA half-life. The data indicate that estradiol stimulates newly transcribed hepatic apoA-I mRNA, resulting in a selective increase in LP A-I, a subfraction of HDL that is associated with decreased atherosclerotic cardiovascular disease, especially in premenopausal women. 相似文献
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我们非常感激你对儿音响产品的关心,并且希望它能成为你家庭音响和家庭影院中的一部分。
当我们进入家庭音响市场的时候,我们公司承诺会以性能和品质的最高标准来创造产品。我们相信你会从Fathom@或者Gofham中的每个细节中看到儿音响对品质的承诺,但最重要的是,我们相信你会在每次欣赏电影和享受音乐的时候都会感受得到。 相似文献
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技术改造项目的技术经济评价方法 总被引:1,自引:0,他引:1
分析比较了技术改造项目的经济评价的计算方法,利用“有无比较法”计算增量净收益,是技术改造项目经济效益计算的有效方法。 相似文献
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