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This study aimed to analyze the effects of caloric restriction on aged femoral articular cartilage of Wistar rats. Three groups of eight animals each were considered: young (YC) and old (OC) control groups fed with a normal diet and old caloric restriction group (OCR) composed of 18-month-old animals fed with a 31% less caloric diet from 6-months of age. Articular cartilage was studied through morphometry and immunohistochemistry. Body mass was 12% less in the OCR group than in the OC group. The articular cartilage from OC rats show thinner medial condyles, fewer chondrocytes, smaller chondrocytes nuclear volume and, in both condyles, a predominance of collagen type II and less collagen density compared to both YC and OCR groups (p?p?相似文献   
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Educational attainment is an attribute that leads to a great distinction between the members of a population, including when considering their health and well-being, which are features to pursue within an aging society. The aim of this work was to produce demographic projections for the Portuguese population by sex, age group and level of educational attainment, for the period 2011–2031. Considering fertility, mortality and migration differentials by level of education, the population was projected using the multistate cohort-component method with a block Leslie matrix. Two scenarios were considered, one where educational attainment before 2011 remains constant and another in which educational attainment will follow the trend observed over the last decade, being the trend in the state proportion modelled using continuation ratio models. The results show an increase in the proportion of individuals who complete higher educational levels in almost all age groups of both sexes. Among women, only 13.6 % had completed some level of higher education in 2011, a figure that will rise to approximately 23.4 % in 2031, whereas among men this value was only 9.7 % and will also rise by 2031, reaching 15.5 %. We can expect the proportion of people with higher educational levels to continue to rise as the education of younger cohorts seems to evolve positively. This work will be particularly useful to study how the aging population and the rising levels of education can contribute to the planning and monitoring of public policies, although these findings can also be used in other research contexts.  相似文献   
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AStA Advances in Statistical Analysis - Count data as response variables are commonly modeled using Poisson regression models, which require equidispersion, i.e., equal mean and variance. However,...  相似文献   
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Journal of Management and Governance -  相似文献   
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Using the data collected from research carried out at two Portuguese universities, this article highlights the way university lecturers currently deal with space and time. Their professional activity is not externally subjected to a specific time geometry that defines their working day. Teaching and researching time–spaces are basically task oriented. Furthermore, university lecturers are increasingly requested to perform tasks in very short time periods in order to secure financial support. To a certain extent, this pressure upon their work is facilitated by the use of technology. However, technology also causes a profound reconfiguration of working times and spaces, especially because it allows lecturers to work at any time from anywhere. This not only renders university physical spaces and times virtual, but it also leads to the colonization of several other time–spaces of their social lives. This article analyses the ambivalence and difficulty of managing time–spaces, as described by the lecturers themselves, with the objective of providing a more accurate awareness of the implications of technology on their lives, as well as the hazards of the progressive externalization of academic work, particularly for women.  相似文献   
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ON THE SIMPLE PROJECTION PREDICTOR IN FINITE POPULATIONS   总被引:19,自引:0,他引:19  
In this paper, necessary and sufficient conditions for optimality of the simple projection predictor (SPP) are considered under a superpopula-tion model with a not necessarily diagonal covariance matrix. Conditions under which the SPP remains optimal, under possible covariance matrix misspecifications, are also considered.  相似文献   
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