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991.
Rats were exposed to two compound solutions, saline-lemon and sucrose-lemon. In Group ALT, trials with one solution alternated
with trials with the other. Group BLK received all trials with one solution before any trials with the other. Previous retardation
tests had implied that only alternating exposure would establish sucrose as an inhibitor of saline. To provide a complementary
summation test for this inhibition, in Experiment 1, all the animals received pairings of peppermint and saline and were tested
for consumption of peppermint-sucrose under sodium depletion. Consumption was increased by sodium depletion only in Group
BLK. In Experiment 2, a retardation test was used to show that presentation of saline-lemon before sucrose-lemon on each exposure
day would establish sucrose as an inhibitor of saline. Neither exposure to sucrose-lemon before saline-lemon nor alternating
exposure to sucrose and saline alone had the same effect. These results provide support for an associative theory of perceptual
learning that suggests that exposure to complex stimuli aids later discrimination partially as a result of establishing inhibitory
associations between their unique elements. 相似文献
992.
993.
日本的国家级教育政策研究机构包括国家级政府主导的公务机关性质的教育政策研究机构、独立行政法人性质的教育政策研究机构和大学或大学附属性质的教育政策研究机构。为了更有助于国家层面教育政策的整体规划和深度推进,日本文部科学省对原有的国家级教育政策研究机构进行了改革重组,强化了其服务于政府宏观教育决策的职能。以代表日本国家级教育政策研究机构的国立教育政策研究所为例,改革后其职能为:准确恰当并且迅速地应对教育行政上的诸多课题;回应教育基层实践的要求,进行全面综合地调查研究;向教育相关者提供教育研究情报信息;开展教育领域的国际性的共同研究;推进与地方政府的教育研究所或研究中心等的共同研究。日本国家级教育政策研究机构的改革与发展,为我国教育政策研究的科学化发展提供了参考和启示。 相似文献
994.
995.
A nationwide purposive sample of secondary vocational educators completed a questionnaire that examined practices and perceptions toward grading students with disabilities. A variety of grading methods was reportedly used, but over two-thirds of respondents included a competency-based grading component. An overwhelming majority believed that student effort should be used to determine grades. Two-thirds of vocational educators had never been involved in their students' IEP development. The most common changes teachers have made over time in their grading practices included becoming more flexible and individualized in grading. Overall, teachers displayed moderately positive attitudes toward grading students with disabilities. 相似文献
996.
Julia D. Plummer Valerie M. Zahm Rebecca Rice 《Journal of Science Teacher Education》2010,21(4):471-493
This study investigated the impact of an open inquiry experience on elementary science methods students’ understanding of
celestial motion as well as the methods developed by students to answer their own research questions. Pre/post interviews
and assessments were used to measure change in participants’ understanding (N = 18). A qualitative approach was used to describe the nature of each participant’s investigation through an analysis of
their science journal and poster presentations. A comparison of participants’ inquiry projects with the change in their understanding
revealed that while most participants improved in both their area of inquiry and beyond, elementary science methods students
may need more guidance to reach a full scientific understanding across all aspects of celestial motion. 相似文献
997.
Interactivity, group learning and student engagement are accepted as key features of social constructivist learning theories.
The challenge is to understand the interplay between such features in different learning environments. This study focused
on the qualitative differences between two interventions—small-groups and whole-class discussions. In both interventions,
three short video slices on the abstract topic ‘the physics of superconductivity’ were interspersed with the different discussion
styles. The video slices are based on the Bruner stages. Twenty-nine first year university physics students completed a pre-test,
underwent the intervention and completed a post-test. The remainder of the data were collected from student drawings, video
recordings, observer notes and facilitator feedback. Results indicate that the use of the video slices in both interventions
were successful in changing students’ understandings of superconductivity. However, the small groups treatment tended to facilitate
questioning, meaning-making and subsequent changes of ideas more so than the whole class discussions. Implications for research
and practice are discussed. 相似文献
998.
The present study was undertaken to clarify the pathogenesis of cisplatin-induced acute renal failure at the early stage.
Male Sprague-Dawley rats were given an intravenous administration of 10 mg/kg cisplatin. 0.9% saline was infused into them
at a rate of 2 ml/h for 3 h, starting with a 2-ml bolus injection before cisplatin administration. 3 h following cisplatin
administration, no evident morphological abnormalities were found by both light and electron microscopy; there were also no
significant changes in GFR. Thirty min after cisplatin injection, urine sodium and potassium excretion increased by 56% and
260% those of the control animals, respectively. Apparent renal mitochondrial respiration dysfunction was observed in cisplatintreated
rats 3 h later; the state 4 respiration increased by 100% and state 3 respiration, respiratory control ratio and carbonyl
cyanide p-trifluoromethoxyphenyl hydrazone-uncoupled respiration decreased by 46%, 74% and 47% of the controls, respectively.
The present data suggest that mitochondrial dysfunction may be a very early event in cisplatin-induced acute renal failure
in rats. 相似文献
999.
Royalties, evolving patent rights, and the value of innovation 总被引:1,自引:0,他引:1
Edward F. Sherry 《Research Policy》2004,33(2):179-191
The value of an innovation to the innovator can change over time, especially in response to changes in the legal protection (such as patent rights) afforded the innovator. A proven-valid-and-infringed patent is a more valuable economic commodity than is an untested patent. The increase in value can be estimated using the success rate of patent lawsuits. Using a database of the outcomes of U.S. patent litigation, we find that plaintiffs win patent litigation some 45% of the time at the trial court level. This has implications both for patent damages awards and for the incentives to innovate. 相似文献
1000.
We present evidence on productivity improvement experienced by the research institutes of the Chinese Academy of Sciences (CAS) after its implementation of the Knowledge Innovation Program (KIP). Using a balanced panel of data on R&D inputs and outputs of 59 research institutes in CAS, we analyze the productivity, technological and efficiency changes from 1997 to 2005. We document that the CAS research institutes have a productivity growth of 12.5% from 1998 to 2005, which can be further decomposed into 8.8% attributed to technological progress and 3.3% to efficiency improvement. Results of regional analysis show that institutes in Beijing and Shanghai, performed better than institutes in other regions during the same period. 相似文献