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The results of this study indicate that urbanization has the effect of significantly altering the Guajiro's sense of ideal and feared identity. It was hypothesized that an attempt would be made to minimize dissonance between the ideal and the real or "true" self which the individual privately acknowledges. However, there is found to be considerable dissonance between ideal and real identities, with the latter actually including many components of feared identity. Defective socialization in the city is suggested as a possible reason for failure to achieve ideal standards.  相似文献   
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Several microphagous grazers co-exist on British rocky shores.The nature of the microbial film which is their prime food sourceis outlined. The radula morphology, hardness, and feeding mechanismsof rhipidoglossan trochids (Gibbula, Monodonta) taenioglossanLittorina, and docoglossan Patella have been compared. Docoglossanscan penetrate hard substrates deeply, taenioglossans can onlypenetrate softer substrates, and rhipidoglossans appear to primarilybrush the surface. A preliminary study found some differencesin diet. Whether feeding mechanisms allow partitioning of themicrofloral film and whether this allows continuing co-existenceof intertidal grazers is discussed.  相似文献   
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Estimating functionals of particle size distributions   总被引:1,自引:0,他引:1  
WATSON  G. S. 《Biometrika》1971,58(3):483-490
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A. WATSON  S. PAYNE  R. RAE 《Ibis》1989,131(3):336-348
This paper contrasts changes in breeding numbers and breeding success of Golden Eagles Aquila chrysaetos on four areas with different land uses. On land primarily used for deer stalking but also for grouse shooting, and supporting abundant prey, the number of eagle pairs was steady in 1944-80. On deer land with fewer prey, the number of pairs declined greatly in the 1960s, when deer carrion became scarcer following increased shooting of red deer. On grouse moors incorporating deer stalking, the number of pairs declined in the 1950s due to persecution by gamekeepers, and then largely recovered as this lessened. On grouse moors with little or no stalking, the number of pairs fell after 1946 and remained low due to persecution, which has continued since then. Eagles on grouse moors bred poorly due to persecution. On deer land they were seldom persecuted by estate staff, and bred well. On an area of deer land, the mean annual number of young reared per undisturbed clutch in summer was related to the estimated weight of prey in the spring of the same year. The eagles have remained fairly pesticide-free, and bred well in 1963-65 when more contaminated birds in west Scotland bred poorly.  相似文献   
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