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1.
Since the 1979 Soviet invasion of Afghanistan, more than 6 million Afghan refugees have become the world''s largest refugee population. Although refugees in Pakistan and Iran are now beginning to repatriate, continuing political turmoil in Afghanistan and children''s acculturation and educational opportunities will keep many Afghans in the United States permanently. Although there are no accurate statistics, local resettlement agencies and Afghan community leaders estimate that there are 10,000 to 35,000 Afghans in northern California. They suffer from a variety of problems common to refugees: language, economic and occupational problems, and substantial challenges in psychological, family, social, and cultural adjustment to the United States. Although many Afghans are doing well, many others have depression, psychosomatic symptoms, and posttraumatic stress disorder.  相似文献   

2.
Sea‐level rise (SLR) due to global warming will result in the loss of many coastal areas. The direct or primary effects due to inundation and erosion from SLR are currently being assessed; however, the indirect or secondary ecological effects, such as changes caused by the displacement of human populations, have not been previously evaluated. We examined the potential ecological consequences of future SLR on >1,200 islands in the Southeast Asian and the Pacific region. Using three SLR scenarios (1, 3, and 6 m elevation, where 1 m approximates most predictions by the end of this century), we assessed the consequences of primary and secondary SLR effects from human displacement on habitat availability and distributions of selected mammal species. We estimate that between 3–32% of the coastal zone of these islands could be lost from primary effects, and consequently 8–52 million people would become SLR refugees. Assuming that inundated urban and intensive agricultural areas will be relocated with an equal area of habitat loss in the hinterland, we project that secondary SLR effects can lead to an equal or even higher percent range loss than primary effects for at least 10–18% of the sample mammals in a moderate range loss scenario and for 22–46% in a maximum range loss scenario. In addition, we found some species to be more vulnerable to secondary than primary effects. Finally, we found high spatial variation in vulnerability: species on islands in Oceania are more vulnerable to primary SLR effects, whereas species on islands in Indo‐Malaysia, with potentially 7–48 million SLR refugees, are more vulnerable to secondary effects. Our findings show that primary and secondary SLR effects can have enormous consequences for human inhabitants and island biodiversity, and that both need to be incorporated into ecological risk assessment, conservation, and regional planning.  相似文献   

3.
Although scientists have studied and touted the importance of insects to many ecosystem services for decades, insects and insect science are often poorly perceived by the public and by policy makers. Because insects do have important influences on many ecosystem services, they have even greater potential to be used to solve some anthropogenically-caused current global problems. We give several examples where insects are currently being used, or are being considered for future use, as a part of the solution to a global problem, including their potential roles as a part of the solution to sustainable fuel and food systems, deforestation and other environmental degradation, and global inequities. Ecologists have an important role to play in assessing how many of the proposed uses of insects will alter ecological processes and ecosystem services, or how their use may be effectively implemented.  相似文献   

4.
Massive disruptions to a way of life, such as thosebrought on by widespread violence, terror, andgenocide, disorder the body as well as the socialorder. When they flee their homelands, refugees bringtheir experiences of violence and terror with them. Drawing on an ethnographic study of 40 Cambodianrefugees between the ages of 50 and 79 who sufferedfrom one or more chronic illnesses, we explore howrefugees who live with chronic illnesses and aredependent on government support were affected by thethreat of welfare reform. When welfare reformthreatened to cut Cambodian refugees' income, it poseda new crisis for those who were chronically in limboand placed further constraints on their lives. Through their narratives, Cambodian refugees enactedtheir bodily distress and resisted the threat ofwelfare reform. The story of threatened welfarereform in the U.S. and its possible consequences forrefugees is a story of quixotic U.S. politics,policies and antidotes for refugeeism gone awry.  相似文献   

5.
北京香山公园自然景观价值二十年变迁   总被引:1,自引:0,他引:1  
成程  肖燚  饶恩明 《生态学报》2014,34(20):6020-6027
自然景观是由自然环境、物质和景象构成,具有观赏、游览、休闲、疗养等效用和价值的风景综合体或景物。然而,人们在开发利用自然资源时,并没有将自然景观的价值纳入到费用效益分析中,这种对自然景观价值的忽略和低估导致了各种不可逆转的环境问题。如果赋予自然景观合适的经济价值并探究其价值变化,能为其开发利用提供决策支持。以北京香山公园为例,构建了价值评估的指标体系:即自然景观价值为使用价值与非使用价值之和。并对这两种价值分别运用个体旅行费用法和条件价值法进行评估,得出2012年香山公园的使用价值为19.25亿元,非使用价值为3.46亿元。对香山公园在1992—2012年20年间的自然景观价值变化进行深入的研究发现,其景观价值由1992年的0.175亿元增长到2012年的22.71亿元,增长近130倍,速率为1.13亿元/a,游客量的加倍增长、人们游览支出的提高,以及支付意愿的增长是产生该变化的主要原因。随着环境污染和生态破坏的日益加剧以及人们对健康生活的迫切向往,香山公园自然景观价值仍将持续增长,景区当局应全面认识香山公园所承载的价值,在发展旅游的同时也要积极探索解决现有生态环境问题的新思路。  相似文献   

6.
Roger Waldinger's provocative book on migrants’ cross-border lives corroborates many insights already established by transnational migration scholarship. He makes a compelling case for the need to understand migration not just as assimilation – neo, segmented, or otherwise – but also as about how people continue to be simultaneously involved in their homelands, the countries where they settle, and other salient places. I am glad that Waldinger has lent his voice to correct the unproductive divide between immigration and emigration scholarship. But the ‘new’ path he charts forward to right what he sees as wrong with current scholarship is, at times, so selectively formulated and argued that it undercuts its effectiveness.  相似文献   

7.
Microalgae can accumulate fatty acids up to 80% of their dry weight (Chisti 2007). As a consequence the yield per hectare could be higher by a factor of 30 compared to terrestrial oleaginous species. Biodiversity of microalgae is enormous. It is estimated that there are between 200 000 and several million species. Such diversity is an unexplored potential for research and industry. In comparison to terrestrial oleaginous species, microalgae have many characteristics addressing environmental problems with a drastically enhanced oil production. Microalgae are currently generating mediatic enthusiasm, and many start-ups are investing this niche. Nevertheless there are still locks to undo via upstream search, before the expected returns and costs are met and before these technologies can be developed at a large scale.  相似文献   

8.

Background

During the 1980s, approximately three million people migrated from Afghanistan to Pakistan and sought refuge in several cities including the city of Karachi. After the initial settlement of the refugees, the international organizations transitioned the health care of these refugees to the two local non-profit service agencies in Karachi. One of these agencies subsidized health care to the refugees under their care and the other agency encouraged the refugees under their care to utilize governmental and non-governmental private health resources at the disposal of general public. Our objective was to measure the effect of health subsidy on the uptake of contraception among Afghan refugee women and compare them to the group of Afghan women without such a subsidy.

Methodology/Principal Findings

A randomly selected group of 650 married Afghan women-325 women in each group-participated in a detailed survey regarding the knowledge, attitude and practices of family planning and contraceptive use. 90 percent of the women in the health subsidy group had had heard of family planning, compared to the 45 percent in the non-subsidized group. The use of contraceptives was greater than two-fold in the former versus the latter. Results of logistic regression analysis revealed that the refugee women who had had access to subsidized healthcare were significantly more likely to use the contraceptive methods with advancing age as compared to the women in the non-health subsidy group. The difference remained significant after adjusting for other variables.

Conclusions/Significance

Refugee women who are provided subsidized healthcare are more inclined to use contraceptives. It is therefore important that Afghan refugee women living elsewhere in Pakistan be provided healthcare subsidy, whereby their reproductive health indicators could improve with reduced fertility. We strongly encourage facilities introducing such subsidies to refugees in resource poor settings to assess the impact through similar inquiry.  相似文献   

9.
There is a clear need for transformative change in the land management and food production sectors to address the global land challenges of climate change mitigation, climate change adaptation, combatting land degradation and desertification, and delivering food security (referred to hereafter as “land challenges”). We assess the potential for 40 practices to address these land challenges and find that: Nine options deliver medium to large benefits for all four land challenges. A further two options have no global estimates for adaptation, but have medium to large benefits for all other land challenges. Five options have large mitigation potential (>3 Gt CO2eq/year) without adverse impacts on the other land challenges. Five options have moderate mitigation potential, with no adverse impacts on the other land challenges. Sixteen practices have large adaptation potential (>25 million people benefit), without adverse side effects on other land challenges. Most practices can be applied without competing for available land. However, seven options could result in competition for land. A large number of practices do not require dedicated land, including several land management options, all value chain options, and all risk management options. Four options could greatly increase competition for land if applied at a large scale, though the impact is scale and context specific, highlighting the need for safeguards to ensure that expansion of land for mitigation does not impact natural systems and food security. A number of practices, such as increased food productivity, dietary change and reduced food loss and waste, can reduce demand for land conversion, thereby potentially freeing‐up land and creating opportunities for enhanced implementation of other practices, making them important components of portfolios of practices to address the combined land challenges.  相似文献   

10.
Seed ferns, dominant elements of the vegetation in many parts of the world from the Triassic to Cretaceous, were considered to have disappeared at the end of the Cretaceous together with several other groups that had occupied key positions in terrestrial and marine ecosystems such as dinosaurs, plesiosaurs, and ammonoids. Seed-fern demise is generally correlated with competition from diversifying flowering plants through the Cretaceous and the global environmental crisis related to the Chicxulub impact event in the paleotropics at the end of the period. New fossils from Tasmania show that one seed-fern lineage survived into the Cenozoic by at least 13 million years. These fossils are described here as a new species, Komlopteris cenozoicus. Komlopteris is a genus of seed ferns attributed to Corystospermaceae and until now was not known from sediments younger than the Early Cretaceous. Discovery of this "Lazarus taxon," together with the presence of a range of other relictual fossil and extant organisms in Tasmania, other southern Gondwanan provinces, and some regions of northern North America and Asia, underscores high-latitude regions as biodiversity refugia during global environmental crises and highlights their importance as sources of postextinction radiations.  相似文献   

11.
Worth H 《Bioethics》2006,20(5):223-232
Refugees, as forced migrants, have suffered displacement under conditions not of their own choosing. In 2000 there were thought to be 22 million refugees of whom 6 million were HIV positive. While the New Zealand government has accepted a number of HIV positive refugees from sub-Saharan Africa, this hospitality is under threat due to negative public and political opinion. Epidemic conditions raise the social stakes attached to sexual exchanges, contagion becomes a major figure in social relationships and social production, and the fears of the contagious nature of those 'just off the plane' connect refugees to an equally deep-seated fear of racial miscegenation. Jacques Derrida's notion of unconditional hospitality is a dream of a democracy which would have a cosmopolitan form. This means that one cannot decide in advance which refugees one might choose to resettle. This paper will use Derrida's notion of unconditional hospitality to emphasise the fragility of HIV positive refugees' position, caught between becoming newly made New Zealand subjects while at the same time having that subjecthood threatened. For Derrida, both ethics and politics demand both an action and a need for a thoughtful response (a questioning without limit).  相似文献   

12.
Over the next century, ecosystems throughout the world will be responding to rapid changes in climate and rising levels of carbon dioxide, inorganic N and ozone. Because people depend on biological systems for water, food and other ecosystem services, predicting the range of responses to global change for various ecosystem types in different geographic locations is a high priority. Modeling exercises and manipulative experimentation have been the principle approaches used to place upper and lower bounds on community and ecosystem responses. However, each of these approaches has recognized limitations. Manipulative experiments cannot vary all the relevant factors and are often performed at small spatio-temporal scales. Modeling is limited by data availability and by our knowledge of how current observations translate into future conditions. These weaknesses would improve if we could observe ecosystems that have already responded to global change factors and thus presage shifts in ecosystem structure and function. Here we consider whether urban forest remnants might offer this ability. As urban forests have been exposed to elevated temperature, carbon dioxide, nitrogen deposition and ozone for many decades, they may be ahead of the global change “response curve” for forests in their region. Therefore, not only might forests along urbanization gradients provide us with natural experiments for studying current responses to global change factors, but their legacy of response to past urbanization may also constitute space-for-time substitution experiments for predicting likely regional forest responses to continued environmental change. For this approach to be successful, appropriate criteria must be developed for selecting forest remnants and plots that would optimize our ability to detect incipient forest responses to spatial variation in global change factors along urbanization gradients, while minimizing artifacts associated with remnant size and factors other than those that simulate global change. Studying forests that meet such criteria along urban-to-rural gradients could become an informative part of a mixed strategy of approaches for improving forecasts of forest ecosystem change at the regional scale.  相似文献   

13.
Johnson FM 《Mutation research》2003,543(3):201-215
High production volume (HPV) chemicals are produced in or imported to the US in amounts greater than 1 million pounds per chemical per year. The EPA has identified thousands of HPVs. Due to their abundance, such chemicals bring a substantial risk for human exposure, and as a result some level of adverse consequences to health are to be expected. In order to examine the potential for cancer risk associated with HPVs, this paper examines HPVs that have been tested in the National Toxicology Program's rodent cancer bioassay. The chemicals tested in the bioassay represent a small sample of the universe of environmental chemicals to which people are exposed. Unexpectedly, 60% of the 128 HPVs evaluated in the bioassay proved to be rodent carcinogens. This value compares to a predicted prevalence of only 16.5% carcinogens in a previous study. The previous study concluded that HPVs were less likely to be toxic by a variety of other test criteria as well. However, the approach involved identifying putative carcinogens using quantitative chemical structure-activity relationships (QSAR) in contrast to the direct tabulation of bioassay test results performed here. Detailed examination of bioassay results reveals that test outcomes depend heavily on route of administration as well as on dose level, sex, strain, and species used. Since most of these factors have little or no apparent relationship to chemical structure, results of this study suggest that QSAR, as well as virtually all other alternative methods, may not generally provide accurate predictions of carcinogenic potential. As we wait for efficient and effective methods for predicting carcinogens to be developed, people continue to be exposed to environmental carcinogens. Progress on regulating environmental carcinogens as well as on developing more effective test methods has been minimal since "war on cancer" began approximately 30 years ago. The present study questions whether the current strategy for dealing with environmental carcinogens will ever be successful. Close examination of rodent cancer test results seems to suggest that almost all chemicals may have carcinogenic potential in some genotypes under some exposure circumstances. If this hypothesis is correct, it would explain the general lack of progress in developing methods to differentiate carcinogens from noncarcinogens. A completely new strategy for dealing with cancer caused by exposures to environmental chemicals seems to be needed.  相似文献   

14.
Various workers, including T. D. Stewart, claim that the aboriginal Americas were relatively disease-free because of the Bering Strait cold-screen, eliminating many pathogens, and the paucity of zoonotic infections because of few domestic animals. Evidence of varying validity suggests that precontact Americans had their own strains of treponemic infections, bacillary and amoebic dysenteries, influenza and viral pneumonia and other respiratory diseases, salmonellosis and perhaps other food poisoning, various arthritides, some endoparasites such as the ascarids, and several geographically circumscribed diseases such as the rickettsial verruca (Carrion's disease) and New World leishmaniasis and trypanosomiasis. Questionably aboriginal are tuberculosis and typhus. Accordingly, virtually all the “crowd-type” ecopathogenic diseases such as smallpox, yellow fever, typhoid, malaria, measles, pertussis, polio, etc., appear to have been absent from the New World, and were only brought in by White conquerors and their Black slaves. My hypothesis is that native American medical care systems—especially in the more culturally advanced areas—were sufficiently sophisticated to deal with native disease entities with reasonable competence. But native medical systems could not cope with the “crowd-type” disease imports that struck Indian and Eskimos as “virgin field” populations. Reanalysis of native population losses through a genocidal combination of disease, war, slavery and attendant cultural disruption by Dobyns, Cook and others strongly suggest that traditional estimates underplayed the death toll by a factor of the general order of ten. This would make for an immediately pre-contact Indian population of some 90–111 million instead of the traditional 8–11 million. Evidence is growing that Indians may have been no more susceptible to new pathogens than are other “virgin soil” populations, and thus their immune systems need not be considered less effective than those in other people. Present-day high mortality rates in Indians of both continents from infectious disease imports may be more socioeconomic than anything else.  相似文献   

15.
The spread of industrial civilizations has been particularly traumatic for the last remaining hunter-gatherer societies. Manifestations of this include expatriation from ancestral lands, sickness, poverty, and environmental degradation. Northern Australia has been no exception despite remaining a stronghold of Aboriginal cultures and still containing vast areas of relatively intact landscapes. Most Aboriginal people reside in remote settlements where they remain on the negative extreme of basic indicators such as life expectancy and educational attainment. In addition, biodiversity declines are being documented from loss of Aboriginal fire management and invasion by feral species. There has been little consideration of potential health, social, economic, or environmental benefits of routinely hunting, gathering or being on their land. This reflects a Western philosophical position that segregates land management and health policy, a view at odds with Aboriginal peoples’ testimony of the indivisibility of people and land. Here we report perspectives from Arnhemland gathered through observation and unstructured and semistructured interviews. Themes that emerged included the high level of detailed, complex knowledge of their traditionally owned lands, the perceived urgency about passing this on to younger people, and the need that both land and people have for each other for the well-being of both. Primary motivations for returning to traditional lands were gathering food, escaping from stresses, and educating young people. The many barriers included no transport, family problems, frequent funerals, and other cultural or family obligations. This work forms part of a larger transdisciplinary research program that aims to inform policy about sustainable futures in northern Australia.  相似文献   

16.
Since the Soviets invaded Afghanistan in 1979, 3.5 to 4 million refugees have moved into Pakistan and Iran. Even before the war, the health status of the Afghans was extremely poor and the medical personnel limited. Various international efforts are attempting to cope with the health care needs of the refugees. Economic, language, and cultural problems hamper the projects. One clinic found the most common problems were of the gastrointestinal tract, then the respiratory tract, with a problem ranking similar to that of pre-war Afghanistan. Many of the health problems are linked to deficiencies in sanitation and nutrition.  相似文献   

17.
Indonesia, with its ultimate development goal of "developing the people and the community as a whole," in fact is facing problems in the execution of this goal. With a population of more than 200 million persons, different in sociocultural background, educational level and environmental conditions, it is understandable that the process and results of technological choices and transfers for various target groups will be different. A wide range of work systems is found, from the simplest man-tool system to the most complex. The conditions are becoming even more complex, a phenomenon especially evident through studies of their sociocultural, psychological, and environmental factors. As a consequence, if success is to be gained in anticipating and understanding the role of Indonesia in the global competition that lies ahead, a very wise approach to the situation by using local values that are often based on traditional habits and customs in a modern context should be carried out. This approach will require an immense amount of time, dedication and effort. Improvement endeavors that have been carried out in different work systems in different types of activities and industries, showed that if the improvement to be sustained, a holistic, systemic, and interdisciplined participatory approach should be taken into consideration where the technical, economical, ergonomic, sociocultural, energy, and environmental factors will play significant roles.  相似文献   

18.
Understanding the historical biogeography of this global biodiversity hotspot is as important to long-term conservation goals as ecology and evolution are to understanding current patterns and processes. Today’s geography is, however, misleading and typical of only ~2% of the last million years; >90% of that time the region’s land area was 1.5–2.0 times larger as mean sea levels were 62 m below today’s, climates were cooler, and extensive forests and savanna covered the emerged Sunda plains. The region’s land area varied two-fold as sea levels fluctuated up to ±50 m with each of ~50 Pleistocene glacial cycles, and forests expanded and contracted with oscillations in land area and seasonality. This dynamic geographic history is relevant to the development of biogeographic regionalism and shows that it is today’s forests that are refugial, not those of the Last Glacial Maximum. This history affects how species will adapt or shift their ranges in response to global warming and further decreases in land area (submergence of low-lying coastal areas) during the 21st century. The alternative is mass species extinction. The biota is also threatened by the continued destruction of forest, destruction of Mekong River flood-pulse based ecosystems, and continued human population growth. Human biogeography will become more important in conservation planning as tens of millions of people who depend on protected area forests, riverine ecosystems, and coastal habitats become environmental refugees. Conservation scientists need to become more involved in regional ecological education, environmental stewardship, and ecosystem-based adaptation to sustain as much as possible of this rich biota and the ecological services it provides.  相似文献   

19.
Knowledge of the basic mechanisms involved in iron metabolism has increased greatly in recent years, improving our ability to deal with the huge global public health problems of iron deficiency and overload. Several million people worldwide suffer iron overload with serious clinical implications. Iron overload has many different causes, both genetic and environmental. The two most common iron overload disorders are hereditary haemochromatosis and transfusional siderosis, which occurs in thalassaemias and other refractory anaemias. The two most important treatment options for iron overload are phlebotomy and chelation. Phlebotomy is the initial treatment of choice in haemochromatosis, while chelation is a mainstay in the treatment of transfusional siderosis. The classical iron chelator is deferoxamine (Desferal), but due to poor gastrointestinal absorption it has to be administered intravenously or subcutaneously, mostly on a daily basis. Thus, there is an obvious need to find and develop new effective iron chelators for oral use. In later years, particularly two such oral iron chelators have shown promise and have been approved for clinical use, namely deferiprone (Ferriprox) and deferasirox (Exjade). Combined subcutaneous (deferoxamine) and oral (deferiprone) treatment seems to hold particular promise.  相似文献   

20.
BACKGROUND: The PubMed database contains nearly 15 million references from more than 4,800 biomedical journals. In general, authors of scientific articles are addressed by their last name and forename initial. DISCUSSION: In general, names can be too common and not unique enough to be search criteria. Today, Ph.D. students, other researchers and women publish scientific work. A person may not only have one name but several names and publish under each name. A Unique Scientist ID could help to address people in peer-to-peer (P2P) networks. As a starting point, perhaps PubMed could generate and manage such a scientist ID. SUMMARY: A Unique Scientist ID would improve knowledge management in science. Unfortunately in some of the publications, and then within the online databases, only one letter abbreviates the author's forename. A common name with only one initial could retrieve pertinent citations, but include many false drops (retrieval matching searched criteria but indisputably irrelevant).  相似文献   

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