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排序方式: 共有284条查询结果,搜索用时 19 毫秒
131.
Kafkafi Neri; Lipkind Dina; Benjamini Yoav; Mayo Cheryl L.; Elmer Gregory I.; Golani Ilan 《Canadian Metallurgical Quarterly》2003,117(3):464
Conventional tests of behavioral phenotyping frequently have difficulties differentiating certain genotypes and replicating these differences across laboratories and protocol conditions. This study explores the hypothesis that automated tests can be designed to quantify ethologically relevant behavior patterns that more readily characterize heritable and replicable phenotypes. It used SEE (Strategy for the Exploration of Exploration) to phenotype the locomotor behavior of the C57BL/6 and DBA/2 mouse inbred strains across 3 laboratories. The 2 genotypes differed in 15 different measures of behavior, none of which had a significant genotype-laboratory interaction. Within the same laboratory, most of these differences were replicated in additional experiments despite the test photoperiod phase being changed and saline being injected. Results suggest that well-designed tests may considerably enhance replicability across laboratories. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
132.
This article reviews four decades of deinstitutionalisation policies in three Australian states, New South Wales, Victoria and Queensland. It seeks to understand the factors influencing the slow and haphazard progression of the movement and its more contested outcomes such as the redevelopment of some institutions and their replacement with other congregate or cluster housing models that are at odds with the original visions of community care and normalisation. The article highlights the consistent and effective opposition to deinstitutionalisation from some families of institution residents, and the shifting policy frameworks and ideologies—from ‘normalisation’ to ‘choice’—in which it progressed. In particular, the article highlights the intersections between deinstitutionalisation and urban policy. The article is based on a review of existing scholarly literature, policy documents, inquiry reports and media sources. 相似文献
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The decreasing costs of telecommunications and the often increasing costs of transportation have given rise to claims that information-intensive activities are becoming footloose. One of the assumptions underlying these claims is that the cost of distance in telecommunications is negligible or very low. This paper examines the relationship between distance and interaction (telecommunications and transportation) costs and rates, with particular emphasis on the effects of geographical scale. Focusing on data from Israel, it demonstrates that the costs of distance are persistent even in telecommunications systems; that for short distances or small regions, transportation costs are not necessarily higher than telecommunications costs; and that pricing of telecommunications services by governments (or PTT's) often does not reflect the costs of providing the services. This creates a cost distribution which differs from Euclidean geographical distances: discontinuities in the rate structure of telecommunications distort the distance-cost schedules and, by creating barriers, may affect location decisions.The paper also demonstrates that actual interaction costs are context specific and therefore no general model has been formulated. Instead, an accounting procedure, which can be used by decision-makers considering (re)location in specific contexts, is suggested. 相似文献
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Three experiments were conducted to show that engaging in an effort to answer a question markedly influences the processing of information subsequently encountered in the environment. On each of 2 successive days, participants were given a definition test that involved the recall of rare English words cued by their definitions. A lexical-decision task was administered between the 2 definition tests; the timing of the lexical-decision task varied across experiments. A strong target-to-definition priming effect occurred such that prior exposure to words during the lexical-decision task increased their likelihood of being recalled in the final definition test. It also appears that earlier attempts to answer questions affected the acquisition of relevant new material in long-term memory. The role of these priming effects is discussed with respect to the process of updating memory representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
138.
The ability to control conductivity in semiconductor nanostructures is often challenged by surface states trapping the majority of the charge carriers. Addressing this challenge requires a reliable method for assessing electrical properties such as carrier concentration and mobility. Unfortunately, here we are facing another challenge, as the Hall effect is geometrically inapplicable to nanowires while the field effect model is also challenged by the geometry of the common nanowire field effect transistor, and can only yield channel mobility which is very different from Hall mobility. In this paper, we propose a method that combines resistivity and photovoltage measurements with a chemical perturbation to the surface to measure carrier concentration and mobility, as a function of wire diameter, and also to measure the surface state density and the surface band bending before and after the chemical treatment. We apply this method to CVD grown GaN nanowires, before and after a mild HCl etch. Using transmission electron microscope and x-ray photoelectron spectrometry we find that HCl removes the native gallium oxide. The etch is found to reduce the surface state density from 1 × 10(12) to 5.3 × 10(11) cm(2), which is calculated from a reduction of the critical radius for full depletion from 7.6 to 4 nm, and a reduction of the surface band bending from 0.53 to 0.29 eV, observed using surface photovoltage. On the average, the values of carrier concentration we obtain are about ten times smaller, and the mobility about ten times greater, than values obtained using field effect transistors. Interestingly, the weak size dependence of the mobility disappears after etching, suggesting a causal linkage between the as-grown size dependence of the mobility and the density of surface states. The proposed method provides an experimental handle to the study of surface states and their effects on the electrical properties of nanowires. 相似文献
139.
Pop M Sermesant M Mansi T Crystal E Ghate S Peyrat JM Lashevsky I Qiang B McVeigh E Ayache N Wright GA 《IEEE transactions on bio-medical engineering》2011,58(12):3483-3486
The aim of this paper was to compare several in-vivo electrophysiological (EP) characteristics measured in a swine model of chronic infarct, with those predicted by simple 3-D MRI-based computer models built from ex-vivo scans (voxel size <1 mm(3)). Specifically, we recorded electroanatomical voltage maps (EAVM) in six animals, and ECG waves during induction of arrhythmia in two of these cases. The infarct heterogeneities (dense scar and border zone) as well as fiber directions were estimated using diffusion weighted DW-MRI. We found a good correspondence (r = 0.9) between scar areas delineated on the EAVM and MRI maps. For theoretical predictions, we used a simple two-variable macroscopic model and computed the propagation of action potential after application of a train of stimuli, with location and timing replicating the stimulation protocol used in the in-vivo EP study. Simulation results are exemplified for two hearts: one with noninducible ventricular tachycardia (VT), and another with a macroreentrant VT (for the latter, the average predicted VT cycle length was 273 ms, compared to a recorded VT of 250 ms). 相似文献
140.
Shaomin Li Marc Fetscherin Ilan Alon Christoph Lattemann Kuang Yeh 《Management International Review》2010,50(5):635-654
• | This study examines how country-level, industry-level, and firm-level factors affect the extent of corporate communications about CSR in Brazil, Russia, India, and China (BRIC). In particular, using data from the 105 largest MNCs in BRIC, we investigate CSR motives, processes, and stakeholder issues discussed in corporate communications. 相似文献 |