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961.
    
In this work,rhamnolipid production was investigated using waste frying oil as the sole carbon source. By culture in shaking flasks,a naturally isolated strain synthesized rhamnolipid at concentration of 12.47 g/L and its mutant after treatment by UV light increased this productivity to 24.61 g/L. Fermentation was also conducted in a 50 L bioreactor and the productivity reached over 20 g/L. Hence,with a stable and high productive mutant strain,it could be feasible to reuse waste frying oil for rhamnolipid production on industrial scale.  相似文献   
962.
James Rubin 《Interchange》2018,49(2):153-160
The popular attraction of Donald Trump has been a conundrum for many educators who have tried to understand the rationale behind his support. This article presents a philosophical argument for what this implies for curriculum design and the intellectual temperament of the populace. There has been much written about the purpose of education to prepare students to be knowledgeable participants in the democratic process to further the best interests of the country. The foundational skills of critical thinking are an integral component of that process, and should be reevaluated for how they fit into the current curriculum model. Suggestions for how to integrate critical thinking within the traditional school day are presented, along with the rationale for doing so.  相似文献   
963.
964.
What is the relationship between the context and substantive meaning of a measure and the assessment of the reliability of the measure? Does the interpretation of a reliability coefficient depend on the nature of the measure? How does this approach to reliability relate to alternative assessments?  相似文献   
965.
Terrestrial isopods (or woodlice), like the members of the other arthropod taxa, have a sophisticated nervous system that makes them sensitive to specific environmental factors. They can search for survival-related opportunities (e.g., approaching food sources or avoiding sunny areas). Two experiments examined how rotational stress could influence the propensity of common woodlice, Porcellio scaber to exhibit survival-related behaviors such as traveling and rearing up in a hostile environment. Experiment 1 assessed the behaviors of stressed and nonstressed woodlice exposed to a familiar or a novel environment without rewards. Experiment 2 assessed the effects of stress in woodlice given a free choice between a familiar and a novel environment without rewards. In the nonstressed individuals, the results showed a decrease in locomotor activity (habituation) and an increase in the time spent rearing up (sensitization) on the arena’s walls over time. In the stressed individuals, repeated rotation had a detrimental effect on the time spent rearing up, but locomotion was decreased only in the stressed individuals that were not preexposed to the test environment beforehand. In addition, immobilization periods—as a plausible indicator of stress—were longer in the absence of preexposure. It is suggested that preexposure had some antistress protective effects on habituated but not on sensitized, exploratory behaviors in woodlice.  相似文献   
966.
This study examined factors that might affect researchers' willingness to collaborate with a specific researcher and the priorities given to those factors. In addition, it investigated how researchers determined the ownership of collaborative project data and how they determined the order of authorship on collaborative publications in condensed matter physics. In general, researchers rated their intrinsic motivations the highest, such as the quality of ideas a potential collaborator might have and their satisfaction with a past collaboration, followed by their extrinsic motivations, such as the complementary knowledge, skills, or resources the collaborator could provide. In addition, researchers who had a greater number of collaborative projects and researchers who had served as a project PI or co-PI valued the deep-level, personality-related characteristics of a collaborator higher than did those who had not. Younger researchers were more risk averse and more concerned with a collaborator's reputation and the possible cost of a collaboration decision. Additionally, younger researchers indicated more often than older researchers that they did not know whether their project teams followed any rules or norms or engaged in negotiation to determine the order of authorship on collaborative publications.  相似文献   
967.
968.
Although much has been written about formal archival spaces, little scholarship has addressed the physical spaces of community archives. This paper asks: How do community members imagine the physical spaces that steward identity-based community archives? Based on focus groups with more than 54 community archives users at five different community archives sites across Southern California, this paper examines how members of marginalized communities conceive of the physical space inhabited by community archives representing their communities. The sites explored range from a prominent location on a university campus, to storefronts, strip malls, and small cinderblock buildings. Yet across sites, users spoke about community archives spaces as symbolic and affectively moving locations. Many users described their community archives site as a “home-away-from-home,” marked by intergenerational dialog and a profound sense of belonging. For other users, community archives sites were described as “politically generative spaces” which foster dialog and debate about identity, representation, and activism and enable the community to envision its future. And yet, while the very existence of community archives is political, many participants felt that the full political potential of these sites is not yet realized. By listening to the voices of the communities represented and served by community archives, our research both indicates that a shift is warranted in archival metaphors of space and reveals how community archives are personally and politically transformative spaces for the communities they represent and serve.  相似文献   
969.
PURPOSE: This study describes the system architecture and user acceptance of a suite of programs that deliver information about newly updated library resources to clinicians' personal digital assistants (PDAs). DESCRIPTION: Participants received headlines delivered to their PDAs alerting them to new books, National Guideline Clearinghouse guidelines, Cochrane Reviews, and National Institutes of Health (NIH) Clinical Alerts, as well as updated content in UpToDate, Harrison's Online, Scientific American Medicine, and Clinical Evidence. Participants could request additional information for any of the headlines, and the information was delivered via e-mail during their next synchronization. Participants completed a survey at the conclusion of the study to gauge their opinions about the service. RESULTS/OUTCOME: Of the 816 headlines delivered to the 16 study participants' PDAs during the project, Scientific American Medicine generated the highest proportion of headline requests at 35%. Most users of the PDA Alerts software reported that they learned about new medical developments sooner than they otherwise would have, and half reported that they learned about developments that they would not have heard about at all. While some users liked the PDA platform for receiving headlines, it seemed that a Web database that allowed tailored searches and alerts could be configured to satisfy both PDA-oriented and e-mail-oriented users.  相似文献   
970.
Practical Guides     
THE DESIGN OF ADVERTISING by Roy Paul Nelson (Dubuque, IA: Wm C. Brown, 1989—price not given, ISBN 0-697-04374-6)

EXPLORING COLOR PHOTOGRAPHY by Robert Hirsch (Dubuque, IA: Wm. C. Brown, 1989—$30.00, paper, ISBN 0-697-06132-9)

VIDEO HELD PRODUCTION by Ron Whittaker (Mayfield Publishing Co., 1240 Villa St., Mountain View, CA 94041—$34.95, ISBN 0-87484-836- 9)  相似文献   
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