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71.
The purpose of this study was to determine the effects of short-term normoxic and hypoxic exercise on plasma endothelin-1 and nitric oxide levels, and the relationship of arterial compliance and pulmonary artery pressure to endothelin-1. Seven endurance-trained males completed two incremental and two steady-state exercise tests performed at ventilatory threshold in normoxia and hypoxia (fraction of inspired oxygen = 0.14). Plasma endothelin-1was measured throughout steady-state tests. Arterial compliance using applanation tonometry, plasma nitric oxide and pulmonary artery pressure using Doppler echocardiography were measured before and after exercise. Small arterial compliance and pulmonary artery pressure significantly increased following exercise. There were no main effects of condition or time for plasma endothelin-1and nitric oxide levels. There were no significant relationships between plasma endothelin-1 and arterial compliance or pulmonary artery pressure. In conclusion, mechanisms other than the endothelial system may play a role in the exercise-induced changes in small artery compliance in this study population. Moderate hypoxia and a 30-minute steady-state exercise have limited effects on plasma endothelin-1 in endurance-trained males.  相似文献   
72.
Nowadays, some virtual museums include 3D room scenes to show the models of its pieces, just like in real museums. Nevertheless, the generation and maintenance of this kind of scenes is generally difficult and should be done by an expert. For example, any change such as including a new piece or modifying the position of an existing fragment usually requires a different design and the creation of a new scene. In this paper we present a case study on the development of a web-based application to automatize this process. To this end, a database to store both graphic and non-graphic information about the pieces, and some 3D rooms to show them has been created. The designed scenes only contain some pieces of furniture to exhibit the fragments, which will be subsequently included. Thus, when a room is loaded in the web page, its associated pieces are obtained through a query in the database and its models are dynamically included in the original scene. Therefore, the position changes or the inclusion of new pieces are not performed in the 3D model, but in the database. Our application makes the transmission of the knowledge to the general public easier because any new discovered piece can be included in a existing museum effortlessly.  相似文献   
73.
Solihull's development of delegated budgets began in 1981. The experiences of schools and Centre led to the acceptance by Council in 1987 of a scheme for general implementation. The detailed scheme is included in an Appendix to the article, together with examples of vital financial management systems. In his article, the Director of Education explores the effects of delegation of the budget, and with it, the decision‐making process. The school heads’ role gains the natural extension of facility to implement management decisions, but what of the role of the Centre?  相似文献   
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Abstract

Rural landholders are undergoing extended economic hardship, manifested in a range of social and ecological problems that limit the capacity of local areas to recover to economic levels necessary to sustain settlement. The uncertain influence of climate on production represents just one of the range of risk factors that landholders must face. Survival depends on the capacity of landholders to respond strategically to the stress which these risk factors generate. Our research indicates landholders’ capacity to modify land‐management practices, are dictated by their underlying personality traits and by presence or absence of other psychiatric morbidity. Where stresses exist, the capacity of people to respond actively to a planned problem solution diminishes. The psychological profiles of people tend to fall into three groups ‐ those who can generally cope; those who can usually cope but undergo dysfunctional episodes under acute stresses, and those who generally cannot cope.

In the grazing lands of central western Queensland, our findings suggest a predominant personality profile consistent with an ability to cope with isolation and the other particular challenges that characterise this way of life. There are two important implications in these results. The first relates to land stewardship and has significant lessons for government intervention in terms of rural policy and approaches to extension. In particular, there are lessons pertinent to the success of Landcare and associated community based initiatives. The second relates to the broad area of rural health as highlighted by the alarming rates of suicide found in rural Australia. In previous decades, those with personality styles less well‐suited to this industry, found employment in nearby rural towns. This option has declined as government policy has favoured the withdrawal of services and resources, hastening depopulation of rural areas. The resultant weakening of the social fabric of rural society is a cause of tension and stress with serious health implications. Previous approaches to rural sociology have not emphasised individual personality traits in seeking to understand the complexity of the human‐environment relationships which determine land use. Nor has personality been invoked is assessing the potential of landholders to adopt ecologically sustainable practices. Further research is planned to consolidate our findings through comparative investigations in other branches of rural industry. JAgr Educ Ext (2001, 7, 3, pp 167–178)  相似文献   
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Hace ya algunos años Cole y Scribner, con una investigación transcultural que se ha hecho clásica, establecían una distinción clave entre la lecto-escritura como código por una parte y los usos concretos que de ella se hace, por otra. Con el ordenador en la educación ha llegado también el momento de hablar quizá menos del aparato en sí y más de los usos psico-educativos que hacemos de él. En este artículo se analizan los usos del ordenador en la escuela y las implicaciones psicopedagógicas de esos usos, y se plantea también la materialización de la profecía McLuhiana de la aldea global y del aula sin muros. Por primera vez el aula puede cubrir todo el globo y conectar telemáticamente a niños de todas las culturas.  相似文献   
78.
Learning communities have been present in community college settings for more than a decade. The literature suggests that they are generally effective for both participating students and faculty. As economic development increasingly demands greater technological sophistication, and community colleges are faced with increasing numbers of developmentally challenged students, learning communities may be one means to effectively resolve this paradox. This article is directed to those faculty and staff who may be considering the initiation of a learning community. It provides a review of literature, and presents a set of issues currently being addressed at one small community college in Louisiana where a learning community is in the design stage.  相似文献   
79.
The old urban centres are marks of an historical and architectural heritage that should be protected and safeguarded. For such, it is fundamental to have a complete understanding of the genesis, regarding both building and the urban mesh. This fact is essential to the support of qualified, conscientious and sustainable rehabilitation interventions on the old building stock. The research carried out addresses the issue of the old urban centres from the perspective of the analysis and inventory of buildings features. The cataloguing process of the building typologies is presented in this work as a synthesis of the principal construction forms, with the old city centre of Seixal being used as a case study. The identification of building typologies has supported a seismic and fire vulnerability assessment of the old building stock. The assessment methodologies developed and used are based on the detailed survey and building inspection, therefore the building typology cataloguing is essential in the analysis at such a large scale. Then we discussed the strategy for the conservation actions incorporated in a broader risk management policy.  相似文献   
80.
BackgroundAthletes tend to have better visuo-motor performance than do sedentary individuals. However, several basic visual-function and perceptual parameters remain unexplored to date. In this study, we investigated whether differences exist in visual function, performance, and processing between basketball players and individuals without a sport-involvement background.MethodsA total of 33 healthy men with no visual impairment or pathology were divided into 2 groups, depending on the involvement in sport (semi-professional basketball players and sedentary individuals). We tested their baseline heart-rate variability in the resting position apart from subjective questionnaires to determine their physical fitness level, and we checked their visual function, performance, and processing through an extended battery of optometric tests.ResultsThe 2 groups differed in resting heart-rate variability parameters (p < 0.001), confirming their dissimilarities in regular time practising sports per week. The basketball players showed a closer breakpoint and recovery nearpoint of convergence, a higher fusional-vergence rate, better discriminability halos, and better eye–hand coordination (all p values < 0.05).ConclusionThese results show evidence that athletes, basketball players in this case, exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds, suggesting an improvement due to the systematic involvement of those skills during basketball practice.  相似文献   
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