宇宙中最冷的气体     

Collns  GP 郭凯声 《科学中国》2001,(3):58-65

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都是平流层惹的祸——臭氧洞可能影响南极洲的气候     

SarahSinpson  郭凯声 《科学中国》2002,(11):7-8

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Serials standards work: the next frontier     

Tseng SC  Arcand JL  Brugger JM  Finn M  Olson AJ  Somers S 《Library resources & technical services》1990,34(2):139-157

Serials, one of the more complicated areas of library technical endeavors, has lacked the benefit of standards for a long time. Even now, with standards beginning to be available, the majority of institutions are not working within standard serials formats. A survey to determine the use of serials standards in libraries was conducted in 1988 by the American Library Association, Resources and Technical Services Division, Serials Section, Committee to Study Serials Standards. In the spring of 1988 a survey was sent to a group encompassing the Association of Research Libraries members, CONSER participants, United States Newspaper Program participants, Microform Project libraries, and some vendors and librarians who attended the Committee meetings on a regular basis. The survey questionnaire assessed the current level of serials standards awareness of librarians and vendors. Topics included the type of serials systems used, standards relevant to serials control and union listing and whether or not they are implemented, types and levels of training staff received in the application of standards, benefits of the standards, and areas where standards are most needed.  相似文献   

Expanding rural primary care training by employing information technologies: the need for participation by medical reference librarians     

Coggan JM  Crandall LA 《Medical reference services quarterly》1995,14(1):9-16

The use of rural sites to train badly needed primary care providers requires access to sophisticated medical information not traditionally available outside of academic health centers. Medical reference librarians can play a key role in the development of primary care training sites in rural settings. Electronic information technologies, with proactive support from medical reference librarians, can provide current and detailed information without concern for distance from the health science center library. This paper discusses recent developments in technology, describes current challenges to the application of this technology in rural settings, and provides policy recommendations for medical reference librarians to enhance rural primary care training.  相似文献   

Confronting child abuse and neglect and overcoming gaze aversion: the unmet challenge of centuries of medical practice     

Krugman RD  Leventhal JM 《Child abuse & neglect》2005,29(4):307-309

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Potentiation and overshadowing between landmarks and environmental geometric cues     

Horne MR  Pearce JM 《Learning & behavior》2011,39(4):371-382

Rats were required in three experiments to find one of two submerged platforms that were situated in the same pair of diagonally opposite corners of a rectangular grey swimming pool. The experimental groups were trained with landmarks, comprising A4 cards attached to the walls, located in the corners containing the platforms. For the control groups, the landmarks were situated in the corners containing the platforms for half of the trials, and in the other corners for the remaining trials. Learning about the positions of the platforms with reference to the shape of the pool was overshadowed in the experimental groups when the landmarks were white, and enhanced when the landmarks were black. A fourth experiment assessed whether geometric cues influenced the control acquired by the landmarks. As in the previous experiments, the presence of the geometric cues overshadowed learning about the landmarks when they were white, but enhanced learning when the landmarks were black.  相似文献   

Patients' characteristics and providers' attitudes: predictors of screening pregnant women for illicit substance use     

Kerker BD  Horwitz SM  Leventhal JM 《Child abuse & neglect》2004,28(2):209-223

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Biotechnology in the Netherlands: controversy or consensus?     

Guttelin JM 《Public understanding of science (Bristol, England)》2002,11(2):131-142

This paper addresses the issue of public perception of modern biotechnology in the Netherlands. Contrary to expectations, data from the 1999 Eurobarometer on biotechnology indicate that the position of the Dutch public in general is rather ambiguous, which is in contrast to many of its neighboring countries. The issue is described in terms of differences between the Netherlands and other European countries on political-economic, social-cultural, or media coverage indicators. On many indicators, the Dutch population differs from that of other European countries, and the Dutch opinion-leading media present a rather balanced perspective on modern biotechnology.  相似文献   

Phonological processing and emergent literacy in younger and older preschool children     

Anthony JL  Williams JM  McDonald R  Francis DJ 《Annals of dyslexia》2007,57(2):113-137

Phonological awareness, phonological memory, and phonological access to lexical storage play important roles in acquiring literacy. We examined the convergent, discriminant, and predictive validity of these phonological processing abilities (PPA) in 389 3-, 4-, and 5-year-old children. Confirmatory factor analysis supported the validity of each PPA as separate from general cognitive ability and separate from each other. Multigroup structural equation modeling (SEM) with mean structure demonstrated that older preschoolers have better developed latent PPA than younger preschoolers but that the structure of PPA is equivalent. RAN was found uniquely associated with letter knowledge and text discrimination in younger preschoolers, and PA was found uniquely associated with word reading skills in older preschoolers. Finally, general cognitive ability was only indirectly associated with emergent literacy via PPA. These results highlight the importance of PPA in the early literacy development of English-speaking preschool children.  相似文献   

Screening of phonological awareness in the early elementary grades: an IRT approach     

Vloedgraven JM  Verhoeven L 《Annals of dyslexia》2007,57(1):33-50

The purpose of the present study was to explore the possibilities for the assessment of growth in phonological awareness of children in kindergarten and first grade. Phonological awareness was measured using four sets of items involving rhyming, phoneme identification, phoneme blending, and phoneme segmentation. The results of an exploratory factor analysis and analyses conducted within the framework of item response theory showed one latent ability to underlie the different sets of items, which nevertheless differed in difficulty. Analyses in terms of the children’s ability further showed the phonological awareness measures to be sensitive to growth. The amount of information supplied by the different sets of items depended on the children’s level of ability. The conclusion that it is possible to accurately monitor the development of children’s phonological awareness in the early elementary grades appears to be justified, and this possibility opens up new perspectives for the early screening for reading problems and dyslexia.  相似文献