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1.
A logical design that describes the overall structure of proteins, together with a more detailed design describing secondary and some supersecondary structures, has been constructed using the computer-aided software engineering (CASE) tool, Auto-mate. Auto-mate embodies the philosophy of the Structured Systems Analysis and Design Method (SSADM) which enables the logical design of computer systems. Our design will facilitate the building of large information systems, such as databases and knowledgebases in the field of protein structure, by the derivation of system requirements from our logical model prior to producing the final physical system. In addition, the study has highlighted the ease of employing SSADM as a formalism in which to conduct the transferral of concepts from an expert into a design for a knowledge-based system that can be implemented on a computer (the knowledge-engineering exercise). It has been demonstrated how SSADM techniques may be extended for the purpose of modelling the constituent Prolog rules. This facilitates the integration of the logical system design model with the derived knowledge-based system.  相似文献   
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On the internal or parietal surface of the left ventricle in man and in mammals are two papillary muscles, which are almost identical and well developed. In man, these muscles are known as the m. papillaris parietalis anterior sinister and the m. papillaris parietalis posterior dexter, in mammals, the m. papillaris parietalis cranialis sinister and caudalis dexter, or, in shorter form, mm. papillaris parietalis sinister et dexter. In the right ventricle in man, there are two papillary parietal muscles: the mm. papillares anteriores et posteriores. On the septum of this ventricle there is, as in mammals, a muscle called the m. papillaris septalis medialis seu subarteriosus. Beside it are one or several smaller muscles, varying from one individual to another: the mm. papillares septales accessorii seu parvi. In the right ventricle of the mammalian heart is found, in addition to the m. parietalis septalis subarteriosus, already mentioned, a m. papillaris caudalis, more or less well developed in some species and, in the majority of mammals, the m. papillaris septalis cranials, which is always well developed. In certain mammals, there is, in rare cases, a m. papillaris septomarginalis seu parietalis. It may be said, in conclusion, that, in a large number of mammals, there is, on the internal surface of the external wall of the right ventricle, a reasonably well developed m. papillaris parietalis.  相似文献   
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This investigation addresses the mediational role of friends' characteristics between adolescents' activity breadth (i.e., variety in activity participation) and their later adjustment. Data were drawn from 2 longitudinal studies: the Childhood and Beyond (CAB; N = 925) study and the Maryland Adolescent Development in Context Study (MADICS; N = 1,338). Adolescents at Time 2 in each study (8th, 9th, and 11th graders in CAB and 8th graders in MADICS) reported on the breadth of their participation across 5 activity settings: sports, religious, volunteering, community, and school. Friends' characteristics and adolescent adjustment were reported by adolescents at Times 1 and 3. Friends' positive characteristics significantly mediated relations between activity breadth and adolescent depressive affect, self-worth, alcohol use, and problem behavior in both studies. Friends' negative characteristics significantly mediated these relations in CAB, but not in MADICS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Motor nerve terminals on abdominal body-wall muscles 6A and 7A in larval flesh flies were investigated to establish their general structural features with confocal microscopy, transmission electron microscopy, and freeze-fracture procedures. As in Drosophila and other dipterans, two motor axons supply these muscles, and two morphologically different terminals were discerned with confocal microscopy: thin terminals with relatively small varicosities (Type Is), and thicker terminals with larger varicosities (Type Ib). In serial electron micrographs, Type Ib terminals were distinguished from Type Is terminals by their larger cross-sectional area, more extensive subsynaptic reticulum, more mitochondrial profiles, and more clear synaptic vesicles. Type Ib terminals possessed larger synapses and more synaptic contact area per unit terminal length. Although presynaptic dense bars of active zones were similar in mean length for the two terminal types, there were almost twice as many dense bars per synapse for Type Ib terminals. Freeze-fractures through the presynaptic membrane showed particle-free areas indicative of synapses on the P-face, within which were localized aggregations of large intramembranous particles indicative of active zones. These particles were similar in number to those found at active zones of several other arthropod neuromuscular junctions. In general, synaptic structural parameters strongly paralleled those of the anatomically homologous muscles in Drosophila melanogaster. In live preparations, simultaneous focal recording from identified varicosities and intracellular recording indicated that the two terminals produced excitatory junction potentials of similar amplitude in a physiological solution similar to that used for Drosophila.  相似文献   
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We have investigated electrical potential and acoustic emissions signals associated with rock deformation. Five rock types were studied; Clashach, Bentheim and Darley Dale sandstones (all quartz-rich) and a Seljadur basalt and Portland limestone (both quartz-free), both air dry and the rocks were tested in distilled water. Shallow crustal conditions were simulated in a triaxial rock deformation cell with a confining pressure simulating depth of 40 MPa, pore pressures ranging 5–35 MPa, and strain rates 10−7–10−4 s−1. Precursory electric potential signals prior to failure were observed in both saturated and dry samples of the quartz-rich sandstones, but only observed in the water saturated quartz-free rocks. Co-seismic electrical signals were obtained in all tests, providing strong evidence that two of the main sources for precursory and co-seismic signals are the piezoelectric and electrokinetic phenomena. Lowering the strain rate resulted in an increase in the number of acoustic emissions. The pore volume changes during compaction and dilatancy remained approximately constant for all strain rates. Streaming potential generated by fluid flow across the sample was also measured at different stages of deformation. The potential signals increased with the pore pressure gradient.  相似文献   
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Examines possible long-term influences of both divorce and living with a single mother on the development of adolescents' values and plans. How divorce affects children both directly and indirectly through its impact on the mother's resources, attitudes, and socialization goals are also examined. Particular focus is placed on those aspects of family interaction that impact on identity formation as it is linked to educational and occupational goals and to gender-role related behaviors associated with marriage, family, and job plans. Possible benefits as well as potential costs of living with a single mother are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Increasing emphasis is now being placed on the assessment of patient outcomes, both in evaluating medical interventions and in quality assurance initiatives. Clinicians, purchasers, managers and researchers need outcome measures that are valid, reliable and responsive. This paper describes the theory and practice underlying the development of outcome measures for two chronic conditions, asthma and diabetes, for application in ambulatory settings. Existing generic and condition-specific health status and health-related quality-of-life measures were administered to almost 1300 patients. The psychometric properties of these measures were examined to identify those that were of adequate validity and reliability in these population groups. Step-wise regression procedures were then used to identify a core set of scales that best predicted patients' general health perceptions, which could be used in measuring general health outcomes for each of these groups. These core sets consist of up to 40 items, spanning physical function, energy and vitality, emotional well-being and condition-specific aspects of health such as symptom control. Further analysis is being carried out to assess the responsiveness to change of these core item sets.  相似文献   
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