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The purpose of this investigation was to describe the morphological parameters that characterize elite age group divers. Comparisons are made to normative age group data from the Coquitlam Growth Study and the constancy of important characteristics from age group to age group is examined. Data were collected on 27 male and 28 female elite divers who participated in the 1990 North American Age Group Diving Championships. Body build, body composition and skinfold corrected diameters were determined from 36 anthropometric parameters and analysed by ANOVA, t-test and Phantom z-scores procedures. All age groups except the 14- to 15-year-old males were significantly (P < or = 0.05) shorter than their norms but recorded higher androgyny index values. The estimated relative muscle mass increased significantly (P < or = 0.05) with age for males at all ages (40.8-46.3%). The 16- to 18-year-old females had a significantly (P < or = 0.05) larger relative muscle component compared to the younger age groups (40.1-38.4%). When normalized for height, active tissue development of the extremities was comparable between the sexes except in the forearm. The results indicate that at all age levels short stature is an important characteristic for divers. Analysis of regional active tissue development provides further insight into sport-specific prerequisites for success at elite levels.  相似文献   
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This paper considers the background of the Library-Bibliographic Classification as the national classification system of Russia, and its history and application in the USSR. It gives the general characteristic of the LBC structure, content and system of designations, as well as the state of its present updating.  相似文献   
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Archival theory in Italy has a long tradition, going back as far as the second half of the nineteenth century, and with roots in the 17th and 18th centuries. Central theme in the theory is themetodo storico, the principle of provenance, for the first time expressed in the late 19th century by Bonaini and Bongi. In the following decades archivists like Casanova and Cencetti were among the leading authors. Elio Lodolini assigned himself the task to synthesize ideas and notions, within a clear distinctions between records (registratura) and archives. One of the overall characteristics of the rich Italian literature is the stressing of the cultural value of archives. I have twice treated before the theme of archival theory in Italy from the fifties up to the nineties. The first time on the occasion of the 25th anniversary of theScuola speciale per Archivisti e Bibliotecari dell'Università degli Studi “La Sapienza” di Roma in 1989, when there was an international round table on archival science in the State Archives of Rome. My essay,Italian archival science today, has been published in the proceedings of the meeting (cfr. Donato Tamblé,L'archivistica in Italia oggi, inStudi sull'archivistica, by Roma: Elio Lodolini, 1992). Some years later, in 1993, I published a book on contemporary Italian archival theory (Donato Tamblé,La teoria archivistica italiana contemporanea (1950–1990). Profilo storico-critico (Roma, 1993) which was the sequel to the volume of Elio Lodolini on Italian archival history — (Lineamenti di storia dell'archivistica italiana (Roma, 1991). The purpose of my book was that of locating and identifying the scientific object of archival science as it developed and was clarified in the thinking and in the lucubration of the contemporary Italian Archivists.  相似文献   
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