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1.
International research enrolling human subjects has raised an ethical concern regarding the just distribution of benefits between the countries that design the research and the host communities. Although several universal declarations have expressed this concern, a gap between theory and practice continues to exist, as well as a significant divergence between the design of the research protocol and the social context where it will be implemented. Although institutional review boards have made a valuable effort to evaluate international research, their sensitivity to the just sharing of research benefits as well as their attention to the social context must be evaluated. This article analyzes the distribution of benefits in a review of international research in Mexico and produces an ethical reflection based on the results. 相似文献
2.
April M. Schueths 《Ethnic and racial studies》2013,36(13):2438-2456
This article expands the theoretical debate on racist nativism and the specific impact that it has on the experiences of interracial mixed-status couples in the USA. In-depth interviews suggest that the costs of racist nativist microaggressions and macroaggressions are experienced differently, depending on the social status of each member of the couple. Microaggressions target Latinos/as, while racial profiling, a macroaggression, is mainly experienced by Latino men; however, in both cases their white partners also experience rebound racism on behalf of their partners. White women partnered with Latinos experience the greatest rebound effects of racist nativism. Larger macro-policies create a precarious position for couples; this leads them to make calculated legal risks to sustain their families and ultimately constrains their freedoms. 相似文献
3.
Angela S. García 《Ethnic and racial studies》2013,36(11):1849-1870
Drawing on surveys from two Mexican immigrant sending communities, this paper comparatively examines the link between subnational policy structures in US destinations and immigrants' settlement and residency behaviour. It focuses in particular on attrition through enforcement policy at the local and state level that is formed to trigger the voluntary exit of undesirable immigrants. With a twofold comparison of immigrants in three cities and two states, the analysis indicates that immigrants do not alter the duration of time they spend in receiving locales or change their state of residence due to restrictive subnational policies. Rather, economic and social factors more prominently shape immigrants' settlement and residency patterns. The implications of this analysis are discussed with particular attention to the incorporation process for immigrants who remain in destinations with attrition through enforcement policy. 相似文献
4.
Article 100 of the UN Convention on the Law of the Sea requires parties to “cooperate” against maritime piracy, but how this cooperation is to be achieved is undefined. Enforcement is a public good—creating uncompensated benefits for others, thus suffering from free rider problems. The analysis in this article explains why more pirates captured are released than prosecuted, why the United Nations and the International Maritime Organization are seeking to reduce enforcement costs, why some in the shipping industry want to apply the 1988 Convention Against Terrorism at Sea, and why still others want to move prosecution of pirates from national courts to an international court. 相似文献
5.
《Ethnic and racial studies》2012,35(1):40-55
Abstract Over the last fifty years the nature of the provision and financing of health services, and the composition of the foreign-born population in the USA have both evolved significantly. The rapid growth of Mexican immigration in the last fifteen years has created new challenges. Ironically, the Patient Protection and Affordable Care Act of 2010, the sweeping legislation designed to ensure that almost all Americans can obtain health insurance, may reduce access to care for many immigrants by isolating them from the general, formerly uninsured, population. Bi-national and cross-border initiatives between the USA and Mexico along the lines of some developments in Europe are worth encouraging to help ease the current and future barriers to health care for immigrants. 相似文献
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Thomas Soehl & Roger Waldinger 《Ethnic and racial studies》2013,36(9):1489-1510
This paper uses the Pew Hispanic Center's 2006 National Survey of Latinos to study the everyday, routine cross-border activities of travel, remittance sending and telephone communication among Latin American immigrants in the United States. We ask how migrants vary in the intensity of their cross-border connections, distinguishing among the transmigrants, those captured by the host-country national social field, and those who maintain some ongoing home-country tie. We then examine the characteristics associated both with variations in the intensity of connectedness and with each specific type of connection. We show that most migrants maintain some degree of home-country connectedness, with a minority severing ties and a still smaller minority maintaining ties at a high degree of intensity. Connectivity is highly responsive to the location of key social ties, acculturation, and citizenship status, as well as the costs associated with the different types of cross-border activity. 相似文献
8.
We tested the null hypothesis that differences in the seasonal return patterns between stocks of Atlantic salmon, Salmo salar L., are a result of a direct response to the environment, and not under genetic control. Two stocks were used in the experiments, originating from the R. Figga and R. Imsa, respectively. In their native habitat fish from the former are known to return to the home stream as adult salmon early in the summer, while from the latter return during late summer and autumn. By rearing these stocks in the same hatchery and releasing smolts of both stocks together at three sites in southern Norway, it was demonstrated that salmon from the R. Figga stock returned earlier to coastal Norway than salmon from the R. Imsa stock, as maturing adults. Thus, we reject the hypothesis that these stocks are genetically identical in this trait. Within both stocks, multi-sea-winter fish returned earlier than one-sea-winter fish. Within stocks, there was no significant difference in time of return between salmon released as 1- and 2-year-old smolts, or between fish reared from parents ascending the R. Imsa early or late in the season. 相似文献
9.
Andrea M. Quattrini Jennifer McClain-Counts Stephen J. Artabane Adela Roa-Varón Tara C. McIver Michael Rhode Steve W. Ross 《Journal of fish biology》2019,94(4):621-647
In August 2007, October 2008 and September–October 2010, 241 Tucker trawl and plankton net tows were conducted at the surface to depths of 1377 m at six locations in the northern and eastern Gulf of Mexico (GOM) to document leptocephalus diversity and determine how assemblage structure, larval size, abundance and isotopic signatures differ across the region and with depth. Overall, 2696 leptocephali representing 59 distinct taxa from 10 families were collected. Five families accounted for 96% of the total catch with Congridae and Ophichthidae being the most abundant. The top four most abundant species composed 59% of the total catch and included: Ariosoma balearicum, Paraconger caudilimbatus, Rhynchoconger flavus and Ophichthus gomesii. Four anguilliform species not previously documented in the GOM as adults or leptocephali were collected in this study, including Monopenchelys acuta, Quassiremus ascensionis, Saurenchelys stylura and one leptocephalus only known from its larval stage, Leptocephalus proboscideus. Leptocephalus catches were significantly greater at night than during the day. Catches at night were concentrated in the upper 200 m of the water column and significantly declined with increasing depth. Leptocephali abundances and assemblages were significantly different between sites on the upper continental slope (c. 500 m depth) and sites on the middle to lower continental slope (c. 1500–2300 m). Sites on the lower continental slope had a mixture of deep-sea demersal, bathypelagic and coastal species, whereas upper-slope sites contained several numerically dominant species (e.g., A. balearicum, P. caudilimbatus) that probably spawn over the continental shelf and upper slope of the GOM. Standard lengths of the four dominant species differed between sites and years, indicating heterochronic reproduction and potential larval source pools within and outside of the GOM. Stable-isotope analyses (δ13C and δ15N) conducted on 185 specimens from six families revealed that leptocephali had a wide range of isotopic values at the family and size-class levels. Species in the families Muraenidae, Congridae and Ophichthidae had similar δ15N values compared with the broad range of δ15N values seen in the deep-sea families Nemichthyidae, Nettastomatidae and Synaphobranchidae. Stable-isotope values were variably related to length, with δ15N values being positively size correlated in ophichthids and δ13C values being negatively size correlated in A. balearicum and P. caudilimbatus. Results suggest that leptocephali feed in various water depths and masses, and on different components of POM, which could lead to niche partitioning. Ecological aspects of these important members of the plankton community provide insight into larval connectivity in the GOM as well as the early life history of Anguilliformes. 相似文献
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Lauran R. Brewster Brianna V. Cahill Miranda N. Burton Cassady Dougan Jeffrey S. Herr Laura Issac Norton Samantha A. McGuire Marisa Pico Elizabeth Urban-Gedamke Kim Bassos-Hull John P. Tyminski Robert E. Hueter Bradley M. Wetherbee Mahmood Shivji Neil Burnie Matthew J. Ajemian 《Journal of fish biology》2021,98(1):89-101
The whitespotted eagle ray Aetobatus narinari is a tropical to warm-temperate benthopelagic batoid that ranges widely throughout the western Atlantic Ocean. Despite conservation concerns for the species, its vertical habitat use and diving behaviour remain unknown. Patterns and drivers in the depth distribution of A. narinari were investigated at two separate locations, the western North Atlantic (Islands of Bermuda) and the eastern Gulf of Mexico (Sarasota, Florida, U.S.A.). Between 2010 and 2014, seven pop-up satellite archival tags were attached to A. narinari using three methods: a through-tail suture, an external tail-band and through-wing attachment. Retention time ranged from 0 to 180 days, with tags attached via the through-tail method retained longest. Tagged rays spent the majority of time (82.85 ± 12.17% S.D.) within the upper 10 m of the water column and, with one exception, no rays travelled deeper than ~26 m. One Bermuda ray recorded a maximum depth of 50.5 m, suggesting that these animals make excursions off the fore-reef slope of the Bermuda Platform. Individuals occupied deeper depths (7.42 ± 3.99 m S.D.) during the day versus night (4.90 ± 2.89 m S.D.), which may be explained by foraging and/or predator avoidance. Each individual experienced a significant difference in depth and temperature distributions over the diel cycle. There was evidence that mean hourly depth was best described by location and individual variation using a generalized additive mixed model approach. This is the first study to compare depth distributions of A. narinari from different locations and describe the thermal habitat for this species. Our study highlights the importance of region in describing A. narinari depth use, which may be relevant when developing management plans, whilst demonstrating that diel patterns appear to hold across individuals. 相似文献
11.
ABSTRACT. Millions of birds migrate across the Gulf of Mexico each year. However, most studies of migration in this region involve sampling onshore locations during the day, potentially underrepresenting the diversity and abundance of migrants passing the region. We evaluated a potential solution to this problem by recording the flight calls of passing migrants from an oil platform located southeast of the Alabama coast in the Gulf of Mexico. We detected 2762 calls during 30 nights from 9 September to 2 November 1999, and were able to identify 2329 calls to species. Flight calls by nine species of birds represented 23% of all identified calls. The greatest number of calls during one night (1017 calls) and during a 1-h period (257 calls) were recorded on 10 September. The greatest number of calls was recorded 8 h after sunset, with a secondary peak 2 h after sunset. The peak prior to sunrise may indicate the formation of flocks at dawn, and the peak after sunset may have been caused by the first wave of migrants reaching the platform. However, call counts varied extensively, with 98% of all calls recorded during 13 nights and 40% on a single night, possibly resulting from hourly and nightly differences in bird numbers aloft, atmospheric conditions, and artificial lighting conditions. Although recording on oil platforms can be difficult because of mechanical, wind, and wave noise, our results suggest great potential for describing the species composition of passing vocal migrants and the temporal patterns of flight-calling behavior if quiet recording locations can be found. Moreover, flight call monitoring could be a critically important tool for bird conservation in this region, given recent proposals to develop wind power and the potential bird mortality associated with such developments. 相似文献
12.
Martin O'Flaherty 《Ethnic and racial studies》2013,36(5):817-844
As a perspective developed primarily in anthropology, ‘transnationalism’ has until recently been dominated by ethnographic and textual analyses. While not problematic for any particular study, the overwhelming dominance of these methodologies has created two major theoretical shortcomings; a tendency to inflate the prevalence of transnational models of living, and the attribution of an egalitarian or emancipatory character to transnationalism, generally in the absence of systematic evidence. In this article we attempt to remedy these problems by examining the frequency and determinants of one tangible indicator of transnational activity in migrants to Australia: visits home. Our results suggest three important conclusions: 1) not all migrants visit home at all, and only about 11 per cent do so on a regular basis; 2) there are major between-group differences in migrants’ capacity to visit home; and 3) the earlier concepts of assimilation and migration order are of substantial significance in understanding transnationalism. 相似文献
13.
THOMAS BROQUET JONATHAN YEARSLEY ALEXANDRE H. HIRZEL JÉRÔME GOUDET NICOLAS PERRIN 《Molecular ecology》2009,18(6):1048-1060
We present a novel and straightforward method for estimating recent migration rates between discrete populations using multilocus genotype data. The approach builds upon a two-step sampling design, where individual genotypes are sampled before and after dispersal. We develop a model that estimates all pairwise backwards migration rates ( mij , the probability that an individual sampled in population i is a migrant from population j ) between a set of populations. The method is validated with simulated data and compared with the methods of BayesAss and Structure. First, we use data for an island model and then we consider more realistic data simulations for a metapopulation of the greater white-toothed shrew ( Crocidura russula ). We show that the precision and bias of estimates primarily depend upon the proportion of individuals sampled in each population. Weak sampling designs may particularly affect the quality of the coverage provided by 95% highest posterior density intervals. We further show that it is relatively insensitive to the number of loci sampled and the overall strength of genetic structure. The method can easily be extended and makes fewer assumptions about the underlying demographic and genetic processes than currently available methods. It allows backwards migration rates to be estimated across a wide range of realistic conditions. 相似文献
14.
Russell King 《Ethnic and racial studies》2013,36(13):2366-2372
The Age of Migration has been uniquely successful as a student text on international migration, not only filling a niche but defining the field. This review article documents the evolution of the five editions of the book in terms of its core structure and enlarging scope. In a more critical vein, I note some omissions and potential shortcomings, while acknowledging the subjectivity of my perspective. More attention could have been given to the mobilities paradigm, transnationalism, internal and return migration, and quantitative analyses. Nevertheless, this book has done more than any other to ensure that the academic study of migration now occupies a central place in the social sciences. 相似文献
15.
长距离迁徙鸟类对应于能量积累状态的取食行为调整 总被引：5，自引：0，他引：5
WANGYong FrankR.MOORE 《动物学报》2005,51(1):12-23
迁徙鸟类能够预计到迁徙过程中对能量需求的增加和迁徙途中获得能量的不确定性。最佳迁徙理论指出：迁徙停留期的一系列决策受到体内能量状态、取食机会和迁徙时间的影响。利用刚完成春季跨越墨西哥湾迁徙的鸫类,我们研究了取食行为、体内能量状态和能量积累速度的相互关系。我们用雾网捕获了停留的鸫,然后给每只鸟进行了环志和称重,并估测了表皮下积累的脂肪。为了检测体内能量积累大小对取食行为的影响,我们把在野外观察到的鸟分成肥、瘦两组。当一天里被捕获鸟的平均体重低于相关种的瘦体重时,这一天被观察到的取食鸟被归到瘦组,反之就属于肥组。我们同时对一部分鸟用有色环进行了标记,以便能在野外观察到它们时能准确地知道每一只鸟的初始能量积累状态。在春天完成跨越墨西哥湾迁徙以后的鸫大约有50％在到达停留地时就已经消耗了所有的表皮下脂肪。与肥组鸟相比,瘦组的个体在停留期扩展了取食方法和取食基底,增加了取食速度。与此相关的是,瘦鸟表现出体重积累更多、速度更快。我们的数据表明迁徙鸟在到达迁徙中途停留地时的能量状态会影响到它们停留期间的取食行为和继续迁徙时的生理机能,从而影响停留期的长短和在迁徙途中停留与否的决定[动物学报51(1)：12—23,2005]。 相似文献
16.
Long‐distance migratory passerines may exhibit different post‐fledging rearing times between their early and late broods due to limited time and energy resources. This could affect the migratory fuelling behaviour, condition and fitness of juvenile birds. We analysed long‐term (13‐year) biometric data (body mass, fat score) on Barn Swallows ringed at the nest and later recaptured during their initial stages of autumn migration. The return rates of early‐ and late‐born juveniles after overwintering in Africa were further compared to estimate their fitness. We found that juveniles from late broods started migrating south on average 11 days younger compared with juveniles from early broods. Body masses of nestlings did not differ between early and late broods, but juveniles from late broods were in better condition after leaving the nest, possibly due to a longer period of parental care. Having started migration, juveniles from late broods were, however, less efficient in accumulating energy than juveniles from early broods. A younger departure age, together with less efficient fuelling of late brood juveniles, may partly explain the 39% lower return probability and hence lower fitness value of late‐brood juveniles. Our study is the first to show that juveniles from the early and late broods exhibit different fuelling behaviour and departure strategies (in terms of age and timing), which may be reflected in the fitness value of offspring. 相似文献
17.
Raúl Acosta-García 《Ethnic and racial studies》2015,38(4):636-649
New migration flows to Mexico are challenging long-established sociocultural configurations. So far, most studies on immigrants in Mexico have focused on singular ethno-national groups rather than paying attention to the intermingling of people. This paper presents an examination of diversification processes occurring in Guadalajara, Mexico. We contend that these are particularly strained because of the continuing frictions with which the country has to deal due to its already-existing diversity. The many forms of discrimination and racism that many Mexicans are subjected to by their co-nationals are often extended to new arrivals. The increasing complexity of migrant inflows challenges established forms of prejudice in everyday interactions. We argue in this paper that the use of superdiversity as a lens to study diversification processes allows us to better understand the changing dynamics currently taking place in Mexico. 相似文献
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Annika L. Abbott;Yuting Deng;Katie Badwey;Andrew Farnsworth;Kyle G. Horton; 《Ecography》2023,2023(8):e06644
More than two billion birds migrate through the Gulf of Mexico each spring en route to breeding grounds in the USA and Canada. This region has a long history of complex natural and anthropogenic environments as the northern Gulf coast provides the first possible stopover habitats for migrants making nonstop trans-Gulf crossings during spring migration. However, intense anthropogenic activity in the region, which is expanding rapidly at present, makes migrants vulnerable to a multitude of obstacles and increasingly fragments and alters these habitats. Understanding the timing of migrants' overwater arrivals has biological value for expanding our understanding of migration ecology relative to decision-making for nonstop flights, and is imperative for advancing conservation of this critical region through the identification of key times in which to direct conservation actions (e.g. temporary halting of wind turbines, reduction of light pollution). We explored 10 years of weather surveillance radar data from five sites along the northern Gulf of Mexico coast to quantify the daily timing and intensity of arriving trans-Gulf migrants. On a daily scale, we found that migrant intensity peaked an average of nine hours after local sunrise, occurring earliest at easternmost sites. On a seasonal level, the greatest number of arrivals occurred between late April and early May, with peak intensity occurring latest at westernmost sites. Overall intensity of migration across all 10 years of data was greatest at the westernmost sites and decreased moving farther to the east. These findings emphasize the differential spatial and temporal patterns of use of the Gulf of Mexico region by migrating birds, information that is essential for improving our understanding of the ecology of trans-Gulf migration and for supporting data-driven approaches to conservation actions for the migratory birds passing through this critical region. 相似文献
20.
Peggy Levitt 《Ethnic and racial studies》2013,36(13):2283-2290
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