排序方式： 共有38条查询结果，搜索用时 15 毫秒
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J. A. Lawry V. Lupo J. J. Overmier J. Kochevar K. L. Hollis D. C. Anderson 《Learning & behavior》1978,6(2):147-154
Temporal form (continuous vs. pulsating) and shock source (alternating current vs. direct current) were factorially combined to produce four shock treatments. The effects of inescapable presentations of these stimuli on subsequent avoidance response acquisition were measured in dogs (Experiment 1) and in rats (Experiment 2) and revealed an interaction of shock variables. Initially, all groups that received ac shock showed impaired performance for the pulsating and continuous shock conditions; groups that received dc continuous shock were also impaired, while those that received dc pulsating shock were not. While this pattern of interference persisted for dogs, it was transient in rats, with only the ac continuous-shock group continuing to be impaired. Mean avoidance performance were positively related to mean activity levels during inescapable shocks for the dc shock groups but not for the ac shock groups. 相似文献
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Toutkoushian Robert K. Porter Stephen R. Danielson Cherry Hollis Paula R. 《Research in higher education》2003,44(2):121-148
Studies that attempt to evaluate and rank institutions often overlook the research activities of an institution. In this article, we show how readily available data from the Institute of Scientific Inquiry (ISI) may be used to estimate the number of scholarly articles written by an institution's faculty. We show how institutions are ranked according to total publications and the ratio of publications to full-time faculty, how these measures vary by type of institution, and how they are correlated with other selected measures of research resources and institutional quality. 相似文献
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For children whose everyday speech differs greatly from the School English (SE) they encounter in academic materials and settings, it was hypothesized that greater familiarity with SE would be associated with more successful early reading acquisition. Sentence imitation and reading skills of 217 urban African American students in kindergarten through second grade (ages 5 to 8 years) were assessed. Children in each grade varied widely in the extent to which their imitations of SE sentences included phonological and grammatical forms that are acceptable in African American Vernacular English but not in SE. Higher familiarity with SE (reproducing SE features more often when imitating) was associated with better reading achievement, and these relationships were independent of memory ability. 相似文献
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Joseph W. Hollis 《The Teacher Educator》2013,48(2):3-5
There is a good chance that many of your pupils have already learned the science lesson you plan to present. Most science learning, according to this author, takes place in the family setting. 相似文献
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Hollis F. Glaser 《Communication Teacher》2013,27(3):85-88
Objective: To enact a model of collaborative communication, demonstrate communication as coordinated management of meaning, to require active listening during the final, and to help students think through a complex social issue Course: Introduction to Public-Speaking 相似文献
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The dielectric properties of tumour cells are known to differ from normal blood cells, and this difference can be exploited for label-free separation of cells. Conventional measurement techniques are slow and cannot identify rare circulating tumour cells (CTCs) in a realistic timeframe. We use high throughput single cell microfluidic impedance cytometry to measure the dielectric properties of the MCF7 tumour cell line (representative of CTCs), both as pure populations and mixed with whole blood. The data show that the MCF7 cells have a large membrane capacitance and size, enabling clear discrimination from all other leukocytes. Impedance analysis is used to follow changes in cell viability when cells are kept in suspension, a process which can be understood from modelling time-dependent changes in the dielectric properties (predominantly membrane conductivity) of the cells. Impedance cytometry is used to enumerate low numbers of MCF7 cells spiked into whole blood. Chemical lysis is commonly used to remove the abundant erythrocytes, and it is shown that this process does not alter the MCF7 cell count or change their dielectric properties. Combining impedance cytometry with magnetic bead based antibody enrichment enables MCF7 cells to be detected down to 100 MCF7 cells in 1 ml whole blood, a log 3.5 enrichment and a mean recovery of 92%. Microfluidic impedance cytometry could be easily integrated within complex cell separation systems for identification and enumeration of specific cell types, providing a fast in-line single cell characterisation method. 相似文献