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1.
One of the central ethical tenets of research in developing countries is the sponsor's obligation to benefit host participants and communities. Two known models of benefits provision dominate the ethical discourse of research in developing countries. The first model, known as the “reasonable availability,” endorses the obligation to provide interventions proven to be effective at the end of a study. This contrasts with the second model, known as “fair benefits,” which endorses other forms of benefits that host communities may deem as fair beyond those derived directly from the study's findings. This paper explores a third benefit model consistent with the writings of the Human Hereditary and Health in Africa (H3Africa) research initiative. The H3Africa—a North‐South collaborative initiative predicated by U.S. National Institutes of Health, the Wellcome Trust and the African Society of Human Genetics upholds a benefit model that endorses capacity building as the primary obligation of its research agenda. This is evident by the endorsement of mechanisms to strengthen capacity building in its research projects. While capacity building remains a plausible means of improving the expertise, quality and independence of research in Africa, sustainable measures are needed to realizing the full potential for African‐led research on the continent.  相似文献   

2.
The National Institutes of Allergy and Infectious Diseases and International Centers for Tropical Disease Research Network held their 11th annual meeting ‘Research Beyond Boundaries’ on 15–18 April 2002.  相似文献   

3.
The southern limit of the distribution of seagrass species along the west coast of Africa is not yet clearly defined. In March 2008 an expedition was organized in Senegal to search for seagrass beds from Dakar (14°45'15" N, 17°30'31" W) southwards to Tabakouta–Delta du Saloum (13°46'59" N, 16°28'42" W). Cymodocea nodosa and Halodule wrightii were observed in sandy areas of some protected bays of Dakar, around Sarène (14°16'18" N, 16°54'17" W), Joal Fadiouth (14°09'08" N, 16°50'03" W) and the Bamboung–Sourou area (13°50'08" N, 16°33'09" W), and they probably occur all along the coast of Senegal and beyond, perhaps much further south as well.  相似文献   

4.
The elephants of West Africa have experienced a long history of human disturbance. Before 1800 they were much affected by the precolonial empires of the savanna and Sahelian zones, the trans-Saharan trade routes, and the coastal trade established by the Europeans. During the 19th century, the increasing demand for ivory from Europe and North America, the European penetration of the region, and the evolution of breech-loading rifles devastated the remaining elephants. The elephant population of West Africa collapsed before the outbreak of World War I because of intense hunting for ivory. This collapse pre-empted the decline that would have occurred anyway due to the rapid growth of the human population and consequent loss of habitat. Elephants now find themselves in about 70 small isolated populations that cover only 5% of the region. These fragments are very vulnerable – whether in the arid lands or the humid forests – to poaching and general human disturbance. There are few data on numbers; most of the population estimates are guesses. Two-thirds of the populations are thought to consist of fewer than 200 animals and therefore have a low probability of surviving the next century. As more habitat is lost to human activities, West African elephants will soon remain only in protected areas. But many parks and reserves are managed poorly and cannot offer effective protection; they do not guarantee a future for elephants. In addition, their crop-raiding habit makes elephants unpopular in rural communities surrounding protected areas. Human populations are expected to continue growing and resources for conservation are scarce. The future of West African elephants lies in a small network of well-protected areas.  相似文献   

5.
Iltis A 《Bioethics》2006,20(4):180-190
Persons generally must give their informed consent to participate in research. To provide informed consent persons must be given information regarding the study in simple, lay language. Consent must be voluntary, and persons giving consent must be legally competent to consent and possess the capacity to understand and appreciate the information. This paper examines the relationship between the obligation to disclose information regarding risks and the requirement that persons have the capacity to understand and appreciate the information. There has been insufficient attention to the extent to which persons must be able to understand and appreciate study information in order to have their consent deemed valid when the information is provided in simple, lay language. This paper argues that (1) the capacity to understand and appreciate information that should be deemed necessary to give valid consent should be defined by the capacity of the typical, cognitively normal adult and (2) the capacity of the typical, cognitively normal adult to understand and appreciate the concept of risk is limited. Therefore, (3) all things being equal, potential subjects must possess a limited capacity to understand and appreciate risk to be deemed competent to consent to research participation. (4) In some cases investigators ought to require that persons possess a greater than typical capacity to understand and appreciate risk.  相似文献   

6.
We studied consumption and preference of meats of wild species (bushmeat) by inhabitants of Bioko Island, Equatorial Guinea. The aim of the study was to quantify frequency of consumption and stated preferences of the two main ethnic groups (Bubi and Fang) in the island. Although members of both ethnic groups lived on the island, the Fang originated from the continent and maintained strong links with this area. Thus, preference and consumption of the Fang reflected exposure to animals found in the continent as well as on Bioko. A sample of 196 subjects (115 Bubi and 81 Fang) was interviewed using semistructured questionnaires. A total of 55 different bushmeat species was identified as preferred or consumed by interviewees. Principal component analyses of stated consumption and preference indicated differences between ethnic groups in their general responses. Further analyses of the effects of preference and other factors on consumption of the three main species mentioned (blue duiker (Cephalophus monticola), Emin's rat (Cricetomys emini), and brush-tailed porcupine (Atherurus africanus) were undertaken. Proportional odds logistic regression models for ordered categorical response data were employed. Results indicated that age and sex of the respondent did not affect consumption, but ethnic group was statistically significant for the three-study species. Consumption and preference of the different meats (N = 11 species) in relation to their availability in the market and price was studied using multiple linear regressions. Consumption is driven predominantly by availability but there is some influence of preference; price of the meat did not have a significant influence.  相似文献   

7.
The genusDaphnia in Cameroon,West Africa   总被引:2,自引:2,他引:0  
J. Green  G. W. Kling 《Hydrobiologia》1988,160(3):257-261
Three species of the genusDaphnia are recorded from Cameroon.Daphnia obtusa was found in a single lake out of 37 sampled.Daphnia laevis was found in the same lake asD. obtusa and in two other lakes, whileD. rosea was found in three other lakes. All the lakes were at altitudes over 1 000 m. The records can be interpreted either as altitudinal survivals of continually dispersing species, or as relicts in an area whereDaphnia is usually very rare or absent.  相似文献   

8.
Objective:  To identify perceived barriers to capacity building for local research ethics oversight in El Salvador, and to set an agenda for international collaborative capacity building.
Methods:  Focus groups were formed in El Salvador which included 17 local clinical investigators and members of newly formed research ethics committees. Information about the proposed research was presented to participants during an international bioethics colloquium sponsored and organized by the St. Jude Children's Research Hospital in collaboration with the National Ethics Committee of El Salvador and the University of El Salvador. Interviews with the focus group participants were qualitatively analyzed.
Results:  Participants expressed the need to tailor the informed consent process and documentation to the local culture; for example, allowing family members to participate in decision-making, and employing shorter consent forms. Participants indicated that economic barriers often impede efforts in local capacity building. Participants valued international collaboration for mutual capacity building in research ethics oversight.
Conclusions:  Research ethics committees in El Salvador possess a basic knowledge of locally relevant ethical principles, though they need more training to optimize the application of bioethical principles and models to their particular contexts. Challenges increase the value of collaborative exchanges with ethics committee members in the United States. Further research on facilitating communication between host country and sponsor country ethics committees can maximize local research ethics expertise, and thus raise the standard of protecting human participants involved in international research.  相似文献   

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12.
The African elephant consists of forest and savanna subspecies. Both subspecies are highly endangered due to severe poaching and habitat loss, and knowledge of their population structure is vital to their conservation. Previous studies have demonstrated marked genetic and morphological differences between forest and savanna elephants, and despite extensive sampling, genetic evidence of hybridization between them has been restricted largely to a few hybrids in the Garamba region of northeastern Democratic Republic of Congo (DRC). Here, we present new genetic data on hybridization from previously unsampled areas of Africa. Novel statistical methods applied to these data identify 46 hybrid samples – many more than have been previously identified – only two of which are from the Garamba region. The remaining 44 are from three other geographically distinct locations: a major hybrid zone along the border of the DRC and Uganda, a second potential hybrid zone in Central African Republic and a smaller fraction of hybrids in the Pendjari–Arli complex of West Africa. Most of the hybrids show evidence of interbreeding over more than one generation, demonstrating that hybrids are fertile. Mitochondrial and Y chromosome data demonstrate that the hybridization is bidirectional, involving males and females from both subspecies. We hypothesize that the hybrid zones may have been facilitated by poaching and habitat modification. The localized geography and rarity of hybrid zones, their possible facilitation from human pressures, and the high divergence and genetic distinctness of forest and savanna elephants throughout their ranges, are consistent with calls for separate species classification.  相似文献   

13.
生态承载力研究进展   总被引:16,自引:12,他引:16  
基于生态承载力的概念发展,介绍了常用的生态承载力研究方法,包括生态足迹法、人类净初级生产力占用法、状态空间法、综合评价法、系统模型法和生态系统服务消耗评价法,并客观评述了这些方法的优缺点,指出了目前生态承载力研究中存在的薄弱环节。未来生态承载力研究需要完善理论体系,深入研究承载力过程机理与承载机制,将生态系统服务的空间流动因素纳入评估体系,构建完善的评价指标体系,加强生态承载力时空动态评估。最终将生态承载力作为解决生态脆弱区资源环境问题的抓手,建立区域资源环境监测预警机制,并落实到主体功能规划和生态安全建设上,为生态文明建设提供有力的科学依据。  相似文献   

14.
Wide-band tracheids (WBTs) have been found in seedlings of most species of cacti that have fibrous wood in their adult bodies. Consequently, this cell type is now known to be present in almost all cacti. Earlier studies of adult plants revealed WBTs to be present only in cacti with globose or short, broad bodies, whereas all species with large columnar or long slender bodies had fibrous wood without WBTs. However, even these species produce WBTs during the first several months after germination. In species with fibrous wood in their adult bodies (species with large or slender bodies), seedlings undergo a phase transition in wood morphogenesis after a few months and stop producing the juvenile (WBT) wood and begin producing adult (fibrous) wood. If adult plants have an intermediate size, the phase transition is delayed and the plant produces WBT wood for several years. Species with globose bodies repress the phase transition completely and never switch to producing adult (fibrous) wood. Because WBTs are so widespread, they probably originated only once in Cactaceae, not multiple times as suggested earlier, or there may have been just a single origin in the Cactaceae/Portulacaceae clade.  相似文献   

15.
Photosynthetic leaf traits were determined for savanna and forest ecosystems in West Africa, spanning a large range in precipitation. Standardized major axis fits revealed important differences between our data and reported global relationships. Especially for sites in the drier areas, plants showed higher photosynthetic rates for a given N or P when compared with relationships from the global data set. The best multiple regression for the pooled data set estimated Vcmax and Jmax from NDW and S. However, the best regression for different vegetation types varied, suggesting that the scaling of photosynthesis with leaf traits changed with vegetation types. A new model is presented representing independent constraints by N and P on photosynthesis, which can be evaluated with or without interactions with S. It assumes that limitation of photosynthesis will result from the least abundant nutrient, thereby being less sensitive to the allocation of the non‐limiting nutrient to non‐photosynthetic pools. The model predicts an optimum proportionality for N and P, which is distinct for Vcmax and Jmax and inversely proportional to S. Initial tests showed the model to predict Vcmax and Jmax successfully for other tropical forests characterized by a range of different foliar N and P concentrations.  相似文献   

16.
冀北山区滦平县4种新造林地水源涵养能力研究   总被引:2,自引:0,他引:2  
杨建伟  杨建英  何会宾  唐静  赵廷宁 《生态学报》2019,39(18):6731-6737
为研究密云水库上游冀北山区生态水源保护林的生长现状和涵养水源能力,以油松×落叶松(林地Ⅰ)、油松×山杏(林地Ⅱ)、油松×蒙古栎(林地Ⅲ)、侧柏×山杏(林地Ⅳ)4种混交林为研究对象,通过测定林下枯落物层和土壤层特征,分析比较不同林地枯落物和土壤的持水能力及林地水源涵养能力。研究结果表明:枯落物现存量为林地Ⅱ林地Ⅳ林地Ⅰ林地Ⅲ,林地Ⅱ的枯落物层有效持水量最大,为81.30 t/hm~2,林地Ⅰ最小。土壤总孔隙度、毛管孔隙度和非毛管孔隙度最大的均为林地Ⅳ,分别为56.02%、50.26%和5.76%,林地Ⅳ的土壤层有效持水量最大,为1507.90 t/hm~2,林地Ⅲ最小。综合4种林地的枯落物层和土壤层持水能力,可知林地Ⅳ(侧柏×山杏)的水源涵养能力最强,为157.43 mm,林地Ⅲ(油松×蒙古栎)最弱。  相似文献   

17.
Knowledge of spatial patterns of biological diversity is fundamental for ecological and biogeographical analyses and for priority setting in nature conservation, particularly in West Africa where the existing high biodiversity is increasingly threatened by human activities. The maximum entropy approach was used to model the geographic distribution of 3,393 vascular plant species at a spatial resolution of 0.0833°. Species richness decreases along temperature and precipitation gradients with high species numbers in the south and lower numbers towards the north of the transect. All centres of plant species diversity are confined to humid areas in concordance with the high positive correlation between species richness and rainfall which appears to be the most important delimiter for the distribution ranges of many species in the area. The effectiveness of the existing protected areas at regional and national levels is investigated based on the proportion of species covered. Considering the whole study area, 95% of all species are covered by protected areas according to their distribution ranges. However, the proportion of species covered is considerably lower for some countries such as Benin and Togo. Our results could provide guidance for essential land use management interventions to decision‐makers and conservationists in the region.  相似文献   

18.
We reviewed 1333 papers published in Biotropica and the Journal of Tropical Ecology from 1995 to 2004. Only 62 percent of tropical countries were represented in our survey, with 62 percent of the publications based on research conducted in only ten countries. Sixty-two percent of papers had lead authors that were based at institutions outside the country where the research was conducted. Cross-national collaboration was limited, accounting for only 28 percent of papers with multiple authors. To evaluate if our choice of focal journals could have biased our results, we also reviewed 652 papers published in Ecology , Oecologia , Conservation Biology , and Biological Conservation for five randomly selected years from the same time period. While some differences in authorship and the geographic distribution of research existed, the results from these journals generally mirrored patterns observed in the two focal ones—almost 54 percent of publications were based on research conducted in only ten countries, and most studies had lead authors from a developed country. The results of our review suggest that the geographical distribution of research in the tropics is unequal, and that some important regions remain understudied. The results also suggest a need for a greater focus on establishing collaborative relationships with scientists from tropical countries.  相似文献   

19.
The urgent need for new, safe and sustainable interventions against diseases that disproportionally affect the poor is finally receiving global attention and the funding landscape for development projects has significantly improved during the past decade. For the development of new drug and vaccine candidates, clinical trials have become the most important tool to assess their safety and efficacy. Recently, there has been a seismic shift in the number of clinical trials conducted in resource-limited settings. We discuss the current framework of clinical research in sub-Saharan Africa, from building product pipelines to the capacities needed for the conduct of trials according the harmonised Good Clinical Practice (GCP) ICH E6 guideline. We place emphasis on clinical research in neglected tropical diseases which still frequently has to be conducted with limited financial, logistical and human resources. Given those short-comings we recommend minimum standards needed at the local, national and sponsor levels to provide GCP-compliant clinical research.  相似文献   

20.
This article considers the conservation of relict natural habitat in West Africa, especially habitat preserved in traditional sacred groves. Government-sanctioned conservation is contrasted with local grassroots efforts of conservation. Evidence for the ecological value of sacred groves is based on results of a field study of small mammal communities conducted on the Accra Plains of Ghana and on published sources on the conservation and use of sacred groves from various countries. The study employed standard mark-and-recapture techniques for the sampling for terrestrial small mammals, and mist netting for the sampling of bat communities. Pragmatic approaches combining conservation and sustainable use are considered, as are traditional values that have preserved the sacred groves in the past for up to several hundred years in some cases. In part because these groves shelter unique small mammal and plant communities, traditional values and protection mechanisms should be integrated into the newly emerging cultural and religious contexts. The issues encountered during this study reveal that effective conservation involving local peoples requires a concerted interdisciplinary effort. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   

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