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1.
Australian rainforests have been fragmented due to past climatic changes and more recently landscape change as a result of clearing for agriculture and urban spread. The subtropical rainforests of South Eastern Queensland are significantly more fragmented than the tropical World Heritage listed northern rainforests and are subject to much greater human population pressures. The Australian rainforest flora is relatively taxonomically rich at the family level, but less so at the species level. Current methods to assess biodiversity based on species numbers fail to adequately capture this richness at higher taxonomic levels. We developed a DNA barcode library for the SE Queensland rainforest flora to support a methodology for biodiversity assessment that incorporates both taxonomic diversity and phylogenetic relationships. We placed our SE Queensland phylogeny based on a three marker DNA barcode within a larger international rainforest barcode library and used this to calculate phylogenetic diversity (PD). We compared phylo- diversity measures, species composition and richness and ecosystem diversity of the SE Queensland rainforest estate to identify which bio subregions contain the greatest rainforest biodiversity, subregion relationships and their level of protection. We identified areas of highest conservation priority. Diversity was not correlated with rainforest area in SE Queensland subregions but PD was correlated with both the percent of the subregion occupied by rainforest and the diversity of regional ecosystems (RE) present. The patterns of species diversity and phylogenetic diversity suggest a strong influence of historical biogeography. Some subregions contain significantly more PD than expected by chance, consistent with the concept of refugia, while others were significantly phylogenetically clustered, consistent with recent range expansions.  相似文献   

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Heyd D 《Bioethics》1996,10(4):292-309
Beyond the well-known ethical issues involved in medical experimentation on human subjects, experimenting with embryos raises unique and particularly hard problems. Beside the psychological obstacles connected with the fear of 'playing God" and the awe with which we hold the process of the creation of human beings, there are three philosophical problems which are the main subject of the article:
1. The logical problem of circularity: the morality of experimenting on embryos is dependent on the status of the embryo, which in turn is partly decided by experimentation.
2. The metaphysical problem: experiments are justified by the benefits they bring to human subjects; but it is doubtful whether an early embryo is a 'subject" and whether coming into being is a 'benefit".
3. The moral problem: the standard constraint on medical experiments is that they benefit either the individual subject or at least members of a relevantly defined group of patients suffering from the same syndrome. But embryo experimentation is often associated with potential cure to people of a completely different category (like geriatric patients).
Finally, the article discusses the limits of the force of philosophical arguments in the formation of actual policies for regulating such practices as experimenting with embryos. The widely-shared fourteen-day limit is shown to be a sound practical compromise despite the difficulties in justifying it philosophically.  相似文献   

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ObjectiveThe aims of this study were to assess participatory methods for obtaining community views on child health research.BackgroundCommunity participation in research is recognised as an important part of the research process; however, there has been inconsistency in its implementation and application in Australia. The Western Australian Telethon Kids Institute Participation Program employs a range of methods for fostering active involvement of community members in its research. These include public discussion forums, called Community Conversations. While participation levels are good, the attendees represent only a sub-section of the Western Australian population. Therefore, we conducted a telephone survey of randomly selected households to evaluate its effectiveness in eliciting views from a broader cross-section of the community about our research agenda and community participation in research, and whether the participants would be representative of the general population. We also conducted two Conversations, comparing the survey as a recruitment tool and normal methods using the Participation Program.ResultsWhile the telephone survey was a good method for eliciting community views about research, there were marked differences in the profile of study participants compared to the general population (e.g. 78% vs 50% females). With a 26% response rate, the telephone survey was also more expensive than a Community Conversation. The cold calling approach proved an unsuccessful recruitment method, with only two out of a possible 816 telephone respondents attending a Conversation.ConclusionWhile the results showed that both of the methods produced useful input for our research program, we could not conclude that either method gained input that was representative of the entire community. The Conversations were relatively low-cost and provided more in-depth information about one subject, whereas the telephone survey provided information across a greater range of subjects, and allowed more quantitative analysis.  相似文献   

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Can Homegardens Conserve Biodiversity in Bangladesh?   总被引:1,自引:0,他引:1  
In managed landscapes, tree-dominated habitats often show promise for biodiversity conservation. In Bangladesh where natural forest cover is less than 10 percent, homegardens, which are maintained by at least 20 millions households, represent one possible strategy for biodiversity conservation. This study investigated the floristic and structural diversity of 402 homegardens from six regions across southwestern Bangladesh. All plants were censused, totaling 419 species (59% native), including six IUCN Red Listed. The median homegarden (800 m2) contained a mean of 34 species. Each region contained a mean of 293 species in a mean of 67 homegardens. A total of 49,478 individuals (107 per homegarden and 1003 per hectare) of trees and shrubs were counted from 45.2 ha total sampled area. Thus, significant botanical richness was exhibited in the homegardens across southwestern Bangladesh. However, most species were rare: 82 percent of all species including 189 native were found in 50 or fewer homegardens, and 63 species (36 native) were found in only one or two homegardens. Sixty percent of all tree and shrub species had 50 or fewer individuals each. Thus, whereas richness across the landscape was high, serious effort must be made to increase the populations of most species. We propose three main conservation activities: (1) awareness building; (2) protection of existing individuals of rare species; and (3) propagation. Overlaying all of these activities is the inclusion of local communities in the process, who were the ones to retain these species in homegardens in the first place, and the stakeholders who will determine whether homegardens indeed act as long-term repositories to biodiversity conservation.  相似文献   

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Background

Basic courses in most medical schools assess students'' performance by conferring scores. The objective of this work is to use a large score databank for the early identification of students with low performance and to identify course trends based on the mean of students'' grades.

Methodology/Principal Findings

We studied scores from 2,398 medical students registered in courses over a period of 10 years. Students in the first semester were grouped into those whose ratings remained in the lower quartile in two or more courses (low-performance) and students who had up to one course in the lower quartile (high-performance). ROC curves were built, aimed at the identification of a cut-off average score in the first semesters that would be able to predict low performances in future semesters. Moreover, to follow the long-term pattern of each course, the mean of all scores conferred in a semester was compared to the overall course mean obtained by averaging 10 years of data. Individuals in the low-performance group had a higher risk of being in the lower quartile of at least one course in the second semester (relative risk 3.907; 95% CI: 3.378–4.519) and in the eighth semester (relative risk 2.873; 95% CI: 2.495–3.308). The prediction analysis revealed that an average score of 7.188 in the first semester could identify students that presented scores below the lower quartiles in both the second and eighth semesters (p<0.0001 for both AUC). When scores conferred by single courses were compared over time, three time-trend patterns emerged: low variation, upward trend and erratic pattern.

Conclusion/Significance

An early identification of students with low performance may be useful in promoting pedagogical strategies for these individuals. Evaluation of the time trend of scores conferred by courses may help departments monitoring changes in personnel and methodology that may affect a student''s performance.  相似文献   

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Biodiversity hotspots: hot for what?   总被引:2,自引:0,他引:2  
In complex areas of international policy, such as biodiversity conservation, there is a risk that well-promoted strategies will be received by decision makers as a cure-all. The U.S.-based Conservation International is promoting biodiversity hotspots as a 'silver bullet' strategy for conserving most species for least cost. We assess the degree to which this goal is compatible with four social values that characterize the conservation movement. We find that biodiversity hotspots provide only a partial response because conservation does not treat all species as equal. We argue that explicit recognition of such values is fundamental to a structured debate contributing to the development of a common strategy for biodiversity conservation.  相似文献   

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Although the German health care system has budget constraints similar to many other countries worldwide, a discussion on prioritization has not gained the attention of the public yet. To probe the acceptance of priority setting in medicine, a quantitative survey representative for the German public (n = 2031) was conducted. Here we focus on the results for age, a highly disputed criterion for prioritizing medical services. This criterion was investigated using different types of questionnaire items, from abstract age-related questions to health care scenarios, and discrete choice settings, all performed within the same sample. Several explanatory variables were included to account for differences in preference; in particular, interviewee''s own age but also his or her sex, socioeconomic status, and health status. There is little evidence that the German public accepts age as a criterion to prioritize health care services.  相似文献   

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Biodiversity conservation is a required co-benefit of REDD+. Biodiversity monitoring is therefore needed, yet in most areas it will be constrained by limitations in the available human professional and financial resources. REDD+ programs that use forest plots for biomass monitoring may be able to take advantage of the same data for detecting changes in the tree diversity, using the richness and abundance of canopy trees as a proxy for biodiversity. If local community members are already assessing the above-ground biomass in a representative network of forest vegetation plots, it may require minimal further effort to collect data on the diversity of trees. We compare community members and trained scientists’ data on tree diversity in permanent vegetation plots in montane forest in Yunnan, China. We show that local community members here can collect tree diversity data of comparable quality to trained botanists, at one third the cost. Without access to herbaria, identification guides or the Internet, community members could provide the ethno-taxonomical names for 95% of 1071 trees in 60 vegetation plots. Moreover, we show that the community-led survey spent 89% of the expenses at village level as opposed to 23% of funds in the monitoring by botanists. In participatory REDD+ programs in areas where community members demonstrate great knowledge of forest trees, community-based collection of tree diversity data can be a cost-effective approach for obtaining tree diversity information.  相似文献   

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Today, more than ever, robust projections of potential species range shifts are needed to anticipate and mitigate the impacts of climate change on biodiversity and ecosystem services. Such projections are so far provided almost exclusively by correlative species distribution models (correlative SDMs). However, concerns regarding the reliability of their predictive power are growing and several authors call for the development of process-based SDMs. Still, each of these methods presents strengths and weakness which have to be estimated if they are to be reliably used by decision makers. In this study we compare projections of three different SDMs (STASH, LPJ and PHENOFIT) that lie in the continuum between correlative models and process-based models for the current distribution of three major European tree species, Fagussylvatica L., Quercusrobur L. and Pinussylvestris L. We compare the consistency of the model simulations using an innovative comparison map profile method, integrating local and multi-scale comparisons. The three models simulate relatively accurately the current distribution of the three species. The process-based model performs almost as well as the correlative model, although parameters of the former are not fitted to the observed species distributions. According to our simulations, species range limits are triggered, at the European scale, by establishment and survival through processes primarily related to phenology and resistance to abiotic stress rather than to growth efficiency. The accuracy of projections of the hybrid and process-based model could however be improved by integrating a more realistic representation of the species resistance to water stress for instance, advocating for pursuing efforts to understand and formulate explicitly the impact of climatic conditions and variations on these processes.  相似文献   

19.
Vitamin Deficiencies in Humans: Can Plant Science Help?   总被引:1,自引:0,他引:1  
The term vitamin describes a small group of organic compounds that are absolutely required in the human diet. Although for the most part, dependency criteria are met in developed countries through balanced diets, this is not the case for the five billion people in developing countries who depend predominantly on a single staple crop for survival. Thus, providing a more balanced vitamin intake from high-quality food remains one of the grandest challenges for global human nutrition in the coming decade(s). Here, we describe the known importance of vitamins in human health and current knowledge on their metabolism in plants. Deficits in developing countries are a combined consequence of a paucity of specific vitamins in major food staple crops, losses during crop processing, and/or overreliance on a single species as a primary food source. We discuss the role that plant science can play in addressing this problem and review successful engineering of vitamin pathways. We conclude that while considerable advances have been made in understanding vitamin metabolic pathways in plants, more cross-disciplinary approaches must be adopted to provide adequate levels of all vitamins in the major staple crops to eradicate vitamin deficiencies from the global population.  相似文献   

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The Millennium Ecosystem Assessment and other commentators have warned about the impacts that biodiversity decline will have on human health. There is no doubting that the natural world provides mankind with the majority of the resources required to sustain life and health. Many species provide food, fuel, medicines; with the potential for many more (as of yet) undiscovered uses for various species. Despite this, there have been very few attempts to actually investigate relationships between biodiversity (i.e. number of species, rather than the ability of specific species to provide health benefits) and human health. This paper reviews the available evidence and demonstrates that while the links between biodiversity and health seem intuitive, they are very difficult to prove. Socio-economics has a huge influence on health status and the exploitation of natural resources (leading to eventual biodiversity loss) tends to have a positive economic effects. More direct effects of biodiversity on health include the diversity of the internal microbiome, the effect of natural diversity on our mental health and well-being (although this has large social aspects with many people feeling fearful in very diverse environments). Still to be elucidated are the tipping points where the level of global biodiversity loss is such that human health can no longer be sustained.  相似文献   

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