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311.
The main purpose of this study is to gather information about the dimensions of the northern Colombian (Caribbean region) population, focusing on the dimensions of the hand and comparing them with measurements from other regions. Thirty-two hand dimensions were chosen and 120 males and 86 females were measured. Results indicated that there were differences between the dimensions of the hand for men and women, showing that men are larger. Also, there was a comparison made between some measurements of other studies in different regions of Colombia, the USA, Chile, Jordan, Korea and Japan. The results indicated important physiological differences between regions in Colombia and across countries. It was therefore concluded that differences in anthropometric measurements must be included in the design and procurement of machinery and apparatus in order to avoid productivity loss, occupational injuries or illness.  相似文献   
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Not much is known about lay public perceptions of non-native species and their underlying values. Public awareness and engagement, however, are important aspects in invasive species management. In this study, we examined the relations between the lay public’s visions of nature, their knowledge about non-native species, and their perceptions of non-native species and invasive species management with a survey administered in the Netherlands. Within this framework, we identified three measures for perception of non-native species: perceived risk, control and engagement. In general, respondents scored moderate values for perceived risk and personal engagement. However, in case of potential ecological or human health risks, control measures were supported. Respondents’ images of the human–nature relationship proved to be relevant in engagement in problems caused by invasive species and in recognizing the need for control, while images of nature appeared to be most important in perceiving risks to the environment. We also found that eradication of non-native species was predominantly opposed for species with a high cuddliness factor such as mammals and bird species. We conclude that lay public perceptions of non-native species have to be put in a wider context of visions of nature, and we discuss the implications for public support for invasive species management.  相似文献   
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Several Torres Strait communities have significant infrastructure and sacred sites located only a few metres above sea level. As a consequence, these areas are vulnerable to erosion due to the projected increase in storm surge intensity caused by climate change. Common sense suggests that Islanders would welcome new scientific research about how climate change might affect them, in order to understand the significance of these impacts and the timeframes involved. However, one leader has taken a seemingly counterintuitive stance, and has refused to let new climate research occur. We explore why this position was taken, and the implications of this decision for ongoing scientific research. In order to carry out this analysis, we provide a contextual background by assessing Islanders' recent experience with scientific researchers, and the response of policy-makers to it. We find that despite a clearly documented problem with “top-down” decision-making, this process remains. In this instance, we find that there is a systemic lack of collaboration with Islanders to allow them to prioritise their concerns, and a lack of adequate resources to allow them to build their resilience to climate impacts. We conclude that only through a genuine collaborative approach to climate adaptation can activities be properly developed, prioritised and undertaken.  相似文献   
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Disturbance, Diversity, and Invasion: Implications for Conservation   总被引:38,自引:0,他引:38  
Disturbance is an important component of many ecosystems, and variations in disturbance regime can affect ecosystem and community structure and functioning. The "intermediate disturbance hypothesis" suggests that species diversity should be highest at moderate levels of disturbance. However, disturbance is also known to increase the invasibility of communities. Disturbance therefore poses an important problem for conservation management, Here, we review the effects of disturbances such as fire grazing, soil disturbance and nutrient addition on plant species diversity and invasion with particular emphasis on grassland vegetation. Individual components of the disturbance regime can have marked effects on species diversity, but it is often modifications of the existing regime that have the largest influence. Similarly, disturbance can enhance invasion of natural communities, but frequently it is the interaction between different disturbances that has the largest effect. The natural disturbance regime is now unlikely to persist within conservation areas since fragmentation and human intervention have usually modified physical and biotic conditions. Active management decisions must now be made on what disturbance regime is required and this requires decisions on what species are to be encouraged or discouraged.  相似文献   
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Single copies of tiny chromosome fragments, appearing either as single or as double minutes, were observed in a high frequency in amniotic fluid cultures of five mothers who underwent prenatal testing because of advanced age. In four cases, the minutes had arisen de novo. The minutes were later confirmed in fetal skin following termination of pregnancy in one case; in another, in cord blood following the birth of a normal boy; and in the third, in peripheral blood of a normal 3-year-old girl. In the fourth case, the minutes were not confirmed in cord blood following the birth of a normal boy. A follow-up chromosome study of the baby boy in the fifth case was not possible but the minutes were maternally transmitted.  相似文献   
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