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31.
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
32.
33.
What happens when the only staff member who knows how to do a particular task is no longer available? Using NASIG’s Core Competencies for Electronic Resources Librarians, the Electronic Resources and Serials Department of Auburn University set out to tackle the problem of the indispensable staff person, and discovered that expertise is never fully achieved, and competence is always a work in progress. 相似文献
34.
Distributed systems consist of interconnected, lower-dimensional subsystems. For such systems, distributed analysis and design present several advantages, such as modularity, easier analysis and design, and reduced computational complexity. A special case of distributed systems is when the subsystems are connected in a string. Applications include distributed process control, traffic and communication networks, irrigation systems, hydropower valleys, etc. By exploiting such a structure, in this paper, we propose conditions for the distributed stability analysis of Takagi–Sugeno fuzzy systems connected in a string. These conditions are also extended to observer and controller design and illustrated on numerical examples. 相似文献
35.
This paper addresses the role that scientific status plays in initial public offerings of technology focused firms. The paper builds on the literature of the sociology of science as well as the work of Spence (1974) and Podolny (1993) and argues that the presence of a Nobel laureate affiliated with a firm making an IPO provides a signal of firm quality to potential investors. Moreover, and building on the work of Podolny and Scott Morton (1999) and Stuart et al. (1999) we hypothesize that the importance of status diminishes as other measures of firm quality become available. We test our hypothesis for two periods of initial public offerings in biotechnology. We document that there is a clear difference in “maturity” of the firms across the two windows on a number of metrics. Consistent with our hypothesis that Nobel laureates play an important role as a non-financial signal of firm quality, we find that first-window firms with a Nobel laureate affiliate realize greater IPO proceeds in the amount of $24 million. In the second window the amount of money raised is not significantly different between Nobel and non-Nobel firms. This finding is consistent with the signaling literature that argues that the importance of a signal is inversely related to the availability of cogent information on firm quality. Consistent with this view, we also find a change between the two windows in the importance of other non-financial metrics used to convey value. Our research is one of the first to examine the dynamic nature of signals. Because we are unable to distinguish the extent to which the reduction in uncertainty at the firm level is correlated with the reduction of uncertainty at the industry level, the question remains as to the extent to which the diminished importance of signals in our second period is due to a change in market uncertainty versus a change in firm uncertainty. 相似文献
36.
Gurpreet K Rana Doreen R Bradley Stanley J Hamstra Paula T Ross Robert E Schumacher John G Frohna Hilary M Haftel Monica L Lypson 《Journal of the Medical Library Association》2011,99(1):77-81
Objective:
The objective of this study was to validate an assessment instrument for MEDLINE search strategies at an academic medical center.Method:
Two approaches were used to investigate if the search assessment tool could capture performance differences in search strategy construction. First, data from an evaluation of MEDLINE searches from a pediatric resident''s longitudinal assessment were investigated. Second, a cross-section of search strategies from residents in one incoming class was compared with strategies of residents graduating a year later. MEDLINE search strategies formulated by faculty who had been identified as having search expertise were used as a gold standard comparison. Participants were presented with a clinical scenario and asked to identify the search question and conduct a MEDLINE search. Two librarians rated the blinded search strategies.Results:
Search strategy scores were significantly higher for residents who received training than the comparison group with no training. There was no significant difference in search strategy scores between senior residents who received training and faculty experts.Conclusion:
The results provide evidence for the validity of the instrument to evaluate MEDLINE search strategies. This assessment tool can measure improvements in information-seeking skills and provide data to fulfill Accreditation Council for Graduate Medical Education competencies.Highlights
- The University of Michigan MEDLINE Search Assessment tool can be used to assess search skills in residency education.
- Five elements were identified as critical elements in the development of an effective MEDLINE search strategy: inclusion of all search concepts, appropriate use of Medical Subject Headings, appropriate use of search limits, successful combination of all concepts, and search efficiency.
Implications
- This validated assessment tool can serve as an effective means to measure improvements in residents'' information-seeking skills and provide data to fulfill Accreditation Council for Graduate Medical Education competencies.
37.
Christopher P. Dwyer Michael J. Hogan Owen M. Harney John O’Reilly 《Educational technology research and development : ETR & D》2014,62(6):687-709
Critical thinking (CT) is a metacognitive process, consisting of a number of sub-skills and dispositions, that, when used appropriately, increases the chances of producing a logical solution to a problem or a valid conclusion to an argument. CT has been identified as a fundamental learning objective of third-level education; however, students often report not being given the opportunity to adequately understand and cultivate CT skills. Though most CT interventions are designed based on academic or expert definitions of CT skills, students are rarely, if ever, asked to guide their instruction by describing their perspectives on what constitutes CT. The current case study investigated students’ conceptualisations of what constitutes good CT using a collective intelligence methodology, interactive management. Interactive management (IM) is a computer-assisted process that allows a group to build a structural model describing relations between elements in a system. Though decades of research on group decision-making in educational and social psychology highlight the many limitations associated with group problem solving (e.g. as a result of an over-reliance on heuristics, cognitive biases and ‘groupthink’), a fundamental skill for making decisions and solving problems is the ability to collectively visualise the structure of a shared problem, and use this knowledge to design solutions and strategies for collective action. Results of IM group work from the current case study revealed five core CT skills (clarity of expression, conversational skill, inference, evaluation, and explanation), five CT dispositions (detachment, listening, systematicity, recognising uncertainty, and self-questioning) and fourteen structural relationships among them. The ability to detach, listen and engage in conversation with others, were seen as fundamental drivers of all other competencies in the system. Results are discussed in light of research and theory on CT and best practice for CT instruction. 相似文献
38.
Cindy Kovalik Chia-Ling Kuo Megan Cummins Erin Dipzinski Paula Joseph Stephanie Laskey 《TechTrends》2014,58(5):90-94
In this paper, four teachers shared their experiences using the following free Web 2.0 tools with their students: Jing, Wix, Google Sites, and Blogger. The teachers found that students reacted positively to lessons in which these tools were used, and also noted improvements they could make when using them in the future. 相似文献
39.
Bryan Alexander described the digital environment that we live in, giving an extensive overview of the current state of interactive devices, particularly mobile devices, which are moving us beyond the personal computer. He covered recent major developments that have transformed the world in surprising ways in a rather short period of time. The world of apps is further expanding what these devices can do, also bringing with them more challenges to individual privacy. Gaming and augmented reality are becoming deeply embedded in much of what we do. Alexander laid out four possible futures that these contemporary developments could lead to. 相似文献
40.