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811.
Instructor-learner interactions are viewed from the perspective of dynamically self-organizing, coordinated systems. Mothers were asked to instruct their preterm and full-term 24-month-old children to sort blocks according to size and color (a challenging task for children of this age). Dyads were observed for their ability to find a mutual and stable instructional relationship. Dyads in which the child was later identified as having attention-deficit/hyperactivity disorder (ADHD) were marked by significantly less stable organization, less mutuality, and greater perturbations in the system. Mothers of children later found to have ADHD tended to apply stronger constraints than those whose children grew up to have no identified school problems. Implications are drawn for optimal instruction of children who are at risk for central nervous system disorders. 相似文献
812.
P. Chandran N. K. Kuchhal P. Garg C. S. Pundir 《Indian journal of clinical biochemistry : IJCB》2007,22(2):145-150
Chemical composition of gall stones is essential for aetiopathogensis of gallstone disease. We have reported quantitative
chemical analysis of total cholesterol bilirubin, calcium, iron and inorganic phosphate in 120 gallstones from haryana. To
extend this chemical analysis of gall stones by studying more cases and by analyzing more chemical constituents. A quantitative
chemical analysis of total cholesterol, total bilirubin, fatty acids, triglycerides, phospholipids, bile acids, soluble proteins,
sodium potassium, magnesium, copper, oxalate and chlorides of biliary calculi (52 cholesterol, 76 mixed and 72 pigment) retrieved
from surgical operation of 200 patients from Haryana state was carried out. Total cholesterol as the major component and total
bilirubin, phospholipids, triglycerides, bile acids, fatty acids (esterified), soluble protein, calcium, magnesium, iron,
copper, sodium, potassium, inorganic phosphate, oxalate and chloride as minor components were found in all types of calculi.
The cholesterol stones had higher content of total cholesterol, phospholipids, fatty acids (esterified), inorganic phosphate
and copper compared to mixed and pigment stones. The mixed stones had higher content of iron and triglycerides than to cholesterol
and pigment stones. The pigment stones were richer in total bilirubin, bile acids, calcium, oxalate, magnesium, sodium, potassium,
chloride and soluble protein compared to cholesterol and mixed stones. Although total cholesterol was a major component of
cholesterol, mixed and pigment gall stone in Haryana, the content of most of the other lipids, cations and anions was different
in different gall stones indicating their different mechanism of formation. 相似文献
813.
814.
Hugh Clapin Katherine Neal John Wennerbom Barbara Nunn Deborah Dysart Andy Pickering Lisa Featherstone Hiram Caton Dale Jacquette Laura Ruetsche William A. Turner Cornelia Lüdecke Birgit Lohmann James Ladyman Jonathan Coopersmith David Oldroyd Dennis Dean Michael Ruse Nicolas Rasmussen William N. Kaghan Martin Bridgstock Geoffrey Cocks Stephanie H. Kenen Ivan Crozier Sokhieng Au Desmond Barrett Mark Cortiula Ian D. Lawrie 《Metascience》2001,10(1):50-149
815.
N. Vleduts-Stokolov 《Information processing & management》1982,18(6):313-321
The paper describes a technique developed as automatic support to subject heading indexing at BIOSIS. The technique is based on the use of a formalized language for semantic representation of biological texts and subject headings—the language of Concept Primitives. The structure of the language is discussed as well as the structure of the Semantic Vocabulary, in which natural language words from biological texts are described by Concept Primitives. The Semantic Vocabulary is being constructed. Approximately 8,000 entries corresponding to high frequency significant words have been compiled, comprising at least three-quarters of the final number. Results of experiments checking the approach are given, and journal/subject heading and author/subject heading correlation data are analyzed to be used as a supporting technique. 相似文献
816.
This paper presents findings from an analysis of the determinants of the formation of university spin-off companies within the university's research park. We find that university spin-off companies are a greater proportion of the companies in older parks and in parks that are associated with richer university research environments. We also find that university spin-off companies are a larger proportion of companies in parks that are geographically closer to their university and in parks that have a biotechnology focus. 相似文献
817.
N.H. Farhat 《Journal of The Franklin Institute》1973,296(6):393-402
The advantages of real-time microwave holography are reviewed. Real-time capabilities require real-time acquisition of the raw hologram data and real-time retrieval of images from the collected data. This paper examines in detail the acquisition of microwave hologram data by double circular scanning of a single reciever in the context of quasi real-time operation. The principle of the double circular scan is presented and the effect of this sampling format on the retrieved image analyzed. Optical bench simulation of hologram recording employing this sampling format is also presented. It is shown that such a scanning format has the attractive properties of economy, speed (?1 holographic frame/sec) and excellent retrieved image quality. Finally, the compatibility of the double circular scan format with scanned transmitter-receiver holography is discussed in the context of practical low-cost systems. 相似文献
818.
In our target article (Dempster & Corkill, 1999a) we presented an overview of recent work on interference and inhibition in cognition and behavior. The commentators provided highly informative feedback about a range of implications of this new body of work for educational psychology, including learning disabilities. In our response to the commentators, we reply to two relatively broad topics they touch on: consciousness and the functionalist tradition of American psychology. We also remark on two relatively narrow issues raised by the commentators: what constitutes irrelevant information and perseveration in the missing addend task. 相似文献
819.
C. H. Bennett V. L. Scahill D. P. Griffiths N. J. Mackintosh 《Learning & behavior》1999,27(3):333-345
Preexposure to two compound flavors (AX and BX) typically enhances their discriminability: An aversion conditioned to AX will generalize less to BX, especially if the preexposure regime has involved alternated presentations of AX and BX rather than presenting all AX trials before BX trials (or vice versa). One possible explanation of this finding is that alternating preexposure establishes inhibitory associations between the two unique features A and B, thus counteracting the generalization produced by excitatory associations between X and A and between X and B, which might result in either the retrieval of B on a conditioning trial to AX, or the retrieval of A on a test trial to BX. Three experiments on flavor aversion conditioning in rats tested these predictions. Experiment 1 suggested that the more important of these excitatory associations was that which allowed X to retrieve A on the test trial to BX. Experiment 2 suggested that the more important inhibitory association was that which allowed B to inhibit the representation of A on this test trial. Experiment 3 provided direct evidence of the role of this inhibitory B⊣A association. 相似文献
820.