共查询到20条相似文献,搜索用时 15 毫秒
1.
Rafael Alarcón-Medina 《Dialectical Anthropology》2018,42(3):293-308
In recent years, the US government has intensified the deportation of undocumented Mexican migrants, some of them with long life trajectories in the USA. With weak family networks in their communities of origin and sometimes none at all, many deportees choose to stay in cities along the US-Mexico border, joining the army of underpaid, low-skilled, and informal urban workers. Some take advantage of their transnational experience to earn a better income; within this context, the call center industry is an economic sector that profits from the language facility and sociocultural skills deported populations bring with them from their years spent living in the USA. This paper addresses the working conditions among call center workers in Mexico, with a focus in Tijuana City in the Mexican Northwest. In particular, I explore how migration, deportation, and call center labor produces what I call informational return, a process in which the convergence of culture, deportation, and digital media plays a key role in the constitution of a transnational digital worker. 相似文献
2.
Bill Derman 《Human ecology: an interdisciplinary journal》1995,23(2):199-215
Zimbabwe provides a significant context to examine the interplay of the new development rhetoric, the actions of powerful conservation organizations, donor policies, a relatively strong and stable government, and the empowerment of local communities. This interplay exists in diverse rural areas where the Communal Areas Management Program for Indigenous Resources (CAMPFIRE) is in various stages of experimentation and implementation. CAMPFIRE has been described as a philosophy of sustainable rural development that enables rural communities to manage, and benefit directly form indigenous wildlife. It is the best known of African efforts to permit African communities to re- assert their management of selected natural resources. The program has the official support of the Zimbabwean government. Nonetheless, there are many potential areas of serious conflict. Three case studies are utilized to explore how the challenges of repossession of critical environmental resources by marginalized communities in the changing context of state and NGO relationships where international tourism is a revenue generator for both the private sector and government. 相似文献
3.
Interest in mangrove rehabilitation has increased rapidly since 2003, as has awareness of the damaging effects of natural and anthropogenic pressures that contribute to mangrove loss, which is estimated at 1–2 % per annum. The major pressures are from urbanization and other development in all areas and forestry and fisheries especially where communities depend on mangroves for their livelihood. However rehabilitation success has been uncertain, reflecting gaps in integration between human and ecological components of the rehabilitation system. In particular there are government level issues of gaps and inconsistency in policy and failure in application. Some rehabilitation efforts have had limited success for several reasons including: having insufficient information, using inappropriate methods, not involving local communities, or not following all the steps in the processes that have been identified in the literature. A multi-disciplinary and integrated approach is needed to assist future planning and this needs capacity from a variety of areas in government, research and community. The review concludes with hope for a future where governments work with communities to develop policies and strategies for rehabilitating mangrove for resilience to changing environments. 相似文献
4.
DAVID J. S. MONTAGNES JOHN F. DOWER GISELA M. FIGUEIREDO 《The Journal of eukaryotic microbiology》2010,57(3):223-228
ABSTRACT. Since the introduction of the microbial loop concept, awareness of the role played by protozooplankton in marine food webs has grown. By consuming bacteria, and then being consumed by metazooplankton, protozoa form a trophic link that channels dissolved organic material into the “classic” marine food chain. Beyond enhancing energy transfer to higher trophic levels, protozoa play a key role in improving the food quality of metazooplankton. Here, we consider a third role played by protozoa, but one that has received comparatively little attention: that as prey items for ichthyoplankton. For >100 years it has been known that fish larvae consume protozoa. Despite this, fisheries scientists and biological oceanographers still largely ignore protozoa when assessing the foodweb dynamics that regulate the growth and survival of larval fish. We review evidence supporting the importance of the protozooplankton–ichthyoplankton link, including examples from the amateur aquarium trade, the commercial aquaculture industry, and contemporary studies of larval fish. We then consider why this potentially important link continues to receive very little attention. We conclude by offering suggestions for quantifying the importance of the protozooplankton–ichthyoplankton trophic link, using both existing methods and new technologies. 相似文献
5.
Light at night co-distributes with incident breast but not lung cancer in the female population of Israel 总被引:1,自引:0,他引:1
Recent studies of shift-working women have reported that excessive exposure to light at night (LAN) may be a risk factor for breast cancer. However, no studies have yet attempted to examine the co-distribution of LAN and breast cancer incidence on a population level with the goal to assess the coherence of these earlier findings with population trends. Coherence is one of Hill's "criteria" (actually, viewpoints) for an inference of causality. Nighttime satellite images were used to estimate LAN levels in 147 communities in Israel. Multiple regression analysis was performed to investigate the association between LAN and breast cancer incidence rates and, as a test of the specificity of our method, lung cancer incidence rates in women across localities under the prediction of a link with breast cancer but not lung cancer. After adjusting for several variables available on a population level, such as ethnic makeup, birth rate, population density, and local income level, a strong positive association between LAN intensity and breast cancer rate was revealed (p<0.05), and this association strengthened (p<0.01) when only statistically significant factors were filtered out by stepwise regression analysis. Concurrently, no association was found between LAN intensity and lung cancer rate. These results provide coherence of the previously reported case-control and cohort studies with the co-distribution of LAN and breast cancer on a population basis. The analysis yielded an estimated 73% higher breast cancer incidence in the highest LAN exposed communities compared to the lowest LAN exposed communities. 相似文献
6.
Peter Beattie 《Ethnic and racial studies》2017,40(15):2749-2767
Past research on the link between anti-Semitism and criticism of the Israeli government has revealed a partial correlation between the two. However, among the political arguments that have inspired such research, one has gone unaddressed: that criticism of the Israeli government along with silence about more egregious human rights abuses committed elsewhere can only arise from anti-Semitism. This article investigates the link between knowledge of conflicts around the world, anti-Semitism, Islamophobia, and criticism of the Israeli and Saudi governments, among US participants. Using a deeper index of anti-Israel opinions than prior research, the results indicate that some criticisms of the Israeli government are more reliable indicators of anti-Semitic sentiment than others. The findings are discussed with regard to how legitimate political criticism can be distinguished from prejudice in the context of the Israeli–Palestinian conflict. 相似文献
7.
Itai Kloog Abraham Haim Richard G. Stevens Micha Barchana 《Chronobiology international》2013,30(1):65-81
Recent studies of shift‐working women have reported that excessive exposure to light at night (LAN) may be a risk factor for breast cancer. However, no studies have yet attempted to examine the co‐distribution of LAN and breast cancer incidence on a population level with the goal to assess the coherence of these earlier findings with population trends. Coherence is one of Hill's “criteria” (actually, viewpoints) for an inference of causality. Nighttime satellite images were used to estimate LAN levels in 147 communities in Israel. Multiple regression analysis was performed to investigate the association between LAN and breast cancer incidence rates and, as a test of the specificity of our method, lung cancer incidence rates in women across localities under the prediction of a link with breast cancer but not lung cancer. After adjusting for several variables available on a population level, such as ethnic makeup, birth rate, population density, and local income level, a strong positive association between LAN intensity and breast cancer rate was revealed (p<0.05), and this association strengthened (p<0.01) when only statistically significant factors were filtered out by stepwise regression analysis. Concurrently, no association was found between LAN intensity and lung cancer rate. These results provide coherence of the previously reported case‐control and cohort studies with the co‐distribution of LAN and breast cancer on a population basis. The analysis yielded an estimated 73% higher breast cancer incidence in the highest LAN exposed communities compared to the lowest LAN exposed communities. 相似文献
8.
生物群落多样性的测度方法 V.生物群落物种数目的估计方法 总被引:3,自引:0,他引:3
群落的物种数目,即物种丰富度,是最古老、同时也是最基本的一个多样性概念,从对它的估计中可以得到关于物种灭绝速率方面的信息,这对生物多样性保护是非常重要的。已经提出了很多方法来估计群落中的物种数目,这些方法可以分为两大类,即基于理论抽样的方法和基于数据分析的方法。前者包括经典估计方法和贝叶斯估计方法;后者包括对数正态分布的积分方法、再抽样方法和种-面积曲线的外推方法。发现:(1)有些方法适用于动物群落,如大多数基于理论抽样的方法;有些方法则适用于植物群落,如大多数基于数据分析的方法;(2)这些方法还没有经过全面而系统地比较;(3)还没有一个普遍认为比较好的方法。因此,建议采用野外调查与模拟研究相结合的方法对各种估计方法进行系统地评价。 相似文献
9.
Lewis L. Osborne 《Hydrobiologia》1983,99(1):29-36
Community respiration and net primary productivity measurements from precleaned and disturbed substrates of various sizes were collected to examine the colonization and recovery rates of lotic epilithic communities in situ. The assumptions and limitations of the technique for monitoring metabolic recovery are discussed. The results indicate that substrate size and heterogeneity affect the rates of metabolic recovery; metabolic recovery of the heterotrophic community component generally occurs before the autotrophic; following a physical disturbance 13–21 days are required for metabolic recovery while pre-cleaned mixed and homogenous large sized substrates require 15–21 days; a temporary summer metabolic equilibrium appears to exist in the Sheep River, the duration of which is dependent on abiotic environmental variables. Future metabolic studies should include structure and composition measurements to attain maximum information on the recovery of epilithic communities. 相似文献
10.
Lombardo C Bottero S d'Alessandro F Giacomini M Guderzo A Moretti F Marincola M Pesce G Pierotti MA Spagnoli LG Belardelli F 《The International journal of biological markers》2011,26(2):136-138
Training through Research Application Italian iNitiative (TRAIN) is a mobility program financed under the EU action called "Cofinancing of regional, national and international programs" (COFUND) of the European Commission Seventh Framework Program (FP7) - People, and has been designed to encourage the promotion and development of international programs of research through mobility at various stages of research careers. The aim of TRAIN is to improve translational skills in the field of cancer by promoting a three-year international mobility program assigning a total of 51 fellowships subdivided into incoming, outgoing and reintegration fellowships.?The TRAIN proposal has been submitted in February 2009 to the European Commission in reply to the 2008 FP7-PEOPLE-COFUND call and has been successfully evaluated. TRAIN is addressed to postdoctoral scientists or scientists who have at least four years' full-time equivalent research experience and who wish to improve their careers spending one year abroad. The mobility program is open also to non-Italian experienced scientists wishing to spend one year in an Italian research center or private company. Part of the scheme is targeted to experienced Italian scientists who have completed at least three years of research in a foreign country and are interested in returning to Italy.?TRAIN is part of an overall Italian strategy outlined by the International Program of the Italian Cancer Network "Alleanza Contro il Cancro" to promote Italian participation in the building of the European Area for translational cancer research and to enhance the interaction between academy and industry. 相似文献
11.
Drying disturbances are the primary determinant of aquatic community biodiversity in dynamic river ecosystems. Research exploring how communities respond to disturbance has focused on benthic invertebrates in surface sediments, inadequately representing a connected community that extends into the subsurface. We compared subsurface and benthic invertebrate responses to drying, to identify common and context‐dependent spatial patterns. We characterized community composition, alpha diversity and beta diversity across a gradient of drying duration. Subsurface communities responded to drying, but these responses were typically less pronounced than those of benthic communities. Despite compositional changes and in contrast to reductions in benthic alpha diversity, the alpha diversity of subsurface communities remained stable except at long drying durations. Some primarily benthic taxa were among those whose subsurface frequency and abundance responded positively to drying. Collectively, changing composition, stable richness and taxon‐specific increases in occurrence provide evidence that subsurface sediments can support persistence of invertebrate communities during drying disturbances. Beta‐diversity patterns varied and no consistent patterns distinguished the total diversity, turnover or nestedness of subsurface compared to benthic communities. In response to increasing drying duration, beta diversity increased or remained stable for benthic communities, but remained stable or decreased for subsurface communities, likely reflecting contrasts in the influence of mass effects, priority effects and environmental filtering. Dissimilarity between subsurface and benthic communities remained stable or increased with drying duration, suggesting that subsurface communities maintain distinct biodiversity value while also supporting temporary influxes of benthic taxa during drying events. As temporary rivers increase in extent due to global change, we highlight that recognizing the connected communities that extend into the subsurface sediments can enable holistic understanding of ecological responses to drying, the key determinant of biodiversity in these dynamic ecosystems. 相似文献
12.
Emily Weiss Gary Patronek Margaret Slater Laurie Garrison Karen Medicus 《Journal of applied animal welfare science : JAAWS》2013,16(3):221-238
Collaboration among all shelters and nonhuman animal welfare groups within a community along with the transparent, shared reporting of uniform data have been promoted as effective ways to increase the number of animals' lives saved. This article summarizes the shelter intakes, outcomes, and live release rate (LRR) from 6 geographically diverse communities participating in the American Society for the Prevention of Cruelty to Animals Partnership program for 5 years (2007–2011). This program is both a grant program and a coaching program that works to focus the community partners on a data-driven goal using standardized definitions and metrics. There was improvement in LRR in all communities over time regardless of intake numbers, human population, or mix of dogs/puppies and cats/kittens entering shelters. Averaged across all communities over the 5-year period, there was an overall improvement in LRR of 62%. Within individual communities, the degree of improvement ranged from 18% to 96%. This improvement in LRR was accomplished through a wide variety of programs in each community based on resources and interests during the time period. 相似文献
13.
Daniel S. Moen John J. Wiens 《Evolution; international journal of organic evolution》2009,63(1):195-214
Understanding the role of competition in explaining phenotypic diversity is a challenging problem, given that the most divergent species may no longer compete today. However, convergent evolution of extreme body sizes across communities may offer evidence of past competition. For example, many treefrog assemblages around the world have convergently evolved species with very large and small body sizes. To better understand this global pattern, we studied body-size diversification within the small, endemic radiation of Caribbean treefrogs ( Osteopilus ). We introduce a suite of analyses designed to help reveal the signature of past competition. Diet analyses show that Osteopilus are generalist predators and that prey size is strongly associated with body size, suggesting that body-size divergence facilitates resource partitioning. Community assembly models indicate that treefrog body-size distributions in Jamaica and Hispaniola are consistent with expectations from competition. Phylogenetic analyses show that similar body-size extremes in Jamaica and Hispaniola have originated through parallel evolution on each island, and the rate of body-size evolution in Osteopilus is accelerated relative to mainland treefrogs. Together, these results suggest that competition may have driven the rapid diversification of body sizes in Caribbean treefrogs to the extremes seen in treefrog communities around the world. 相似文献
14.
Alain Thiéry 《Hydrobiologia》1991,212(1):117-136
The study of the structure of communities of Crustacean branchiopods Anostraca, Notostraca and Spinicaudata of temporary ponds in Morocco revealed the existence of a geographical area with a particularly diversified number of species. Over a few hectares, 11 species, among the 18 known in Morocco, are present. While most of them are usually allopatric and belong to distinct associations, indicative of particular ecological and climatic conditions, they can coexist in Chaouia plain, either in adjoining ponds (sympatric species) or in the same pond (syntopic species). In one pond we could find up to 10 phyllopods: 6 Anostraca, 2 Notostraca and 2 Spinicaudata.This faunistic diversity may result from abiotic features (the location of the ponds at the boundary of two climatic areas) and from a heterogeneous geological substratum, creating a patchwork of temporary ponds with various mesologic conditions.Secondarily, this diversity may result from different life history characteristics of each coexisting species. As all species hatch synchronically, coexistence is only possible if their growth rates and life span are different. This implies that horizontal and vertical distribution, and exploitation of food supplies in the habitat differ for each ecophase of the syntopic species (spatial and trophic exclusion). 相似文献
15.
Ruth J. Levy 《The Western journal of medicine》1960,92(5):345-347
Recent attempts to cope with the growing and costly problem of mental illness are progressively emphasizing prophylaxis and early detection and treatment. California has joined this trend forcefully since the passage of the Short-Doyle Act in 1957.San Jose is one of the communities with a Community Mental Health program, financed 50 per cent by the local government and 50 per cent by the State of California. It implements its program by offering consultative services to the city''s public health nurses, police officers, teachers, social workers, ministers, sanitarians and members of staffs of a number of public and private agencies.Results of the program have been: (1) Increased demand for education in mental health; (2) growing number of requests for case consultation in lieu of patient-referral to already overburdened psychiatric facilities, and (3) growing recognition by consultees of the importance of their own self-awareness. 相似文献
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Four populations of Cannabis sativa L. grown from seeds collected in Panama, Jamaica, Nepal, and east central Illinois were grown under controlled conditions in growth chambers. One set was grown under warm conditions (32° day and 23° night) and the other set was grown under lower temperatures (23° day and 16° night). CO2 exchange and transpiration were examined under various temperatures and light intensities. Observations on growth, and analyses for chlorophyll and Δ1THC (tetrahydrocannabinol) content were made. Under warm growth conditions, the central Illinois population had the highest photosynthetic rate at all temperatures investigated. The Nepal population had intermediate rates, while the Jamaica and the Panama populations had the lowest rate. The Jamaica and Panama populations had insignificant changes in photosynthetic response to changes in temperatures between 15° and 30°. Under cool growing conditions the central Illinois population had the highest rate of photosynthesis with a definite peak at 25°. Nepal plants had intermediate rates of photosynthesis, while the Panama and Jamaica populations had the lowest rate. Differences in chlorophyll and drug content were also significant between these populations. From these data it is suggested that the four populations can be grouped into different ecotypes genetically adapted to their respective environments. 相似文献
19.
Julienne Corboz 《The Australian journal of anthropology》2013,24(1):64-80
The Latin American literature on Conditional Cash Transfer (CCT) welfare programs has typically involved the quantitative evaluation of social and economic impact, with fewer studies addressing the qualitative and gendered impacts of CCTs. Drawing from ethnographic fieldwork in poor squatter settlement communities in Uruguay, this article explores the everyday social realities of poor single mothers who have been disconnected from their kinship networks and must rely on CCT payments for survival. I locate these women's experiences within the third‐way neoliberal discourses of ‘empowerment’, ‘participation’ and ‘self‐help’ espoused by the state, and the various structural conditions, including crime, violence and unequal gender relations, that impact negatively on women's abilities to comply with their social and civic duties. I argue that rather than producing responsible and empowered subjects, Uruguay's recent CCT welfare program has paradoxically limited some women's participation in civic and public life and reproduced their dependent relations with men. 相似文献
20.
Involving Indigenous community members to assist with the monitoring of harvested populations can greatly assist with the sustainable use of these resources. The benefits of training Indigenous community members in western scientific methods include: increased capability development, increased employment opportunities and more cost effective monitoring output than could be undertaken by government agencies. The aim of this project was to develop a training course to provide elementary scientific skills to Indigenous participants from communities throughout the Northern Territory of Australia. The short term goals of the training were: (1) to increase the capacity of Indigenous communities to conduct monitoring activities and collect biological and physical samples, (2) to increase the employment opportunities for Indigenous community members by providing them with additional skills and a recognised qualification and (3) To provide a cost effective way of conducting monitoring activities in remote areas by using local capability rather than incurring the expense of sending a research team to these locations. The longer term goal of the training is to facilitate the development of research partnerships between Indigenous community members and management agencies as a first step in the move to co-management of aquatic resources. The key components for successfully developing the course were; consistent engagement with Indigenous communities to build relationships and identify priorities for both the community and government agency, the course content involved participation from community members and government scientists, the training addressed the needs of students with English as a second language, the course content was heavily practical and pictorial, assessments were verbal and/or practical and students were housed in accommodation that allowed them to conduct the course to the best of their ability. The research that has been conducted by the participants, as well as three students gaining employment in government research agencies since the completion of the course, suggest that the training has been successful in achieving its short term goals. The research partnerships that have been developed between the government agency and Indigenous community members are still in their infancy, so the move to co-management between these groups is still several years away. However, this training has provided an initial step in this process by increasing the monitoring capability within a substantial number of coastal Indigenous communities that allows them to participate in research programs that underpin the management of their aquatic resources. 相似文献