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1.
Rachel M. Gisselquist 《Ethnic and racial studies》2013,36(9):1605-1627
A considerable amount of recent work in political science and economics builds from the hypothesis that ethnic heterogeneity leads to poor provision of public goods, a key component of poor governance. Much of this work cites Alesina, Baqir and Easterly as providing empirical proof. This paper argues that the findings of this article have been significantly overstated. Through a simple re-analysis of the data, it shows that ethnic diversity does not straightforwardly undermine public goods provision. Rather, at least in these data, the relationship is mixed for different public goods: ethnic diversity is related to lower provision of some public goods and to higher provision of others. In some cases, there is no clear relationship. The differences between the findings presented here and those of the original article are arguably subtle, but are worth noting because of Alesina, et al.'s important contribution to the literature. 相似文献
2.
Laura Moroşanu 《Ethnic and racial studies》2013,36(12):2160-2181
This paper investigates the social ties forged by Romanians in London with migrants of different origins in work and non-work contexts to offer a more nuanced view of ‘bridging’ social ties and related discussions of ‘everyday’ cosmopolitanism. Contrary to the overemphasis on ethnic ties seen as a form of bonding in migration research, the paper shows how Romanians bridge informally with many other migrants based on shared ‘non-native’ status. Alongside non-ethnically marked commonalities, ethnicity emerges as an important ingredient of cosmopolitan socialization, yet without necessarily signalling coexisting ethnic identities, as commonly assumed. Romanians' experiences further show that despite providing significant social and cultural capital, bridging ties with migrants, rather than natives, rarely accrue effective resources for social mobility. The findings suggest the need to disaggregate and qualify current understandings of ‘bridging’ social ties usually depicted in positive terms and uniformly as cross-ethnic relationships, or only linked with the ‘mainstream’ population. 相似文献
3.
Yao-Tai Li 《Ethnic and racial studies》2016,39(4):671-689
The sociological literature has constructed a systematic typology of ‘modes’ and ‘means’ of strategic ethnic boundary making/unmaking. Through exploring different strategies, scholars illustrate the processes and contexts of boundary expansion or contraction. Other scholars also distinguish ethnic elements and ‘moral' values attached to certain ethnicities but not to others. This paper acknowledges dynamic boundary making/unmaking and moral aspects of ethnicity, while exploring the different degrees to which national and pan-national identity nest within each other among ethnic Chinese groups, as well as how ethnic boundary becomes a field where people ‘play' in their everyday interactions. Based on participant observations and in-depth interviews from two pan-Chinese worksites in Australia, the paper argues that different interpretations of ethnic identity as well as how different identities (national and pan-national) are nested give people room to ‘play' at the ethnic boundary and result in different outcomes. This paper also shows that people can cross the ethnic boundary (between Taiwanese/Hong Kongese and PRC-Chinese) without expanding/contracting the existing categories or ‘repositioning/transvaluing' their ethnic statuses. 相似文献
4.
Sarah Signor 《Ecology and evolution》2020,10(7):3402-3412
Transposable elements are abundant, dynamic components of the genome that affect organismal phenotypes and fitness. In Drosophila melanogaster, they have increased in abundance as the species spread out of Africa, and different populations differ in their transposable element content. However, very little is currently known about how transposable elements differ between individual genotypes, and how that relates to the population dynamics of transposable elements overall. The sister species of D. melanogaster, D. simulans, has also recently become cosmopolitan, and panels of inbred genotypes exist from cosmopolitan and African flies. Therefore, we can determine whether the differences in colonizing populations are repeated in D. simulans, what the dynamics of transposable elements are in individual genotypes, and how that compares to wild flies. After estimating copy number in cosmopolitan and African D. simulans, I find that transposable element load is higher in flies from cosmopolitan populations. In addition, transposable element load varies considerably between populations, between genotypes, but not overall between wild and inbred lines. Certain genotypes either contain active transposable elements or are more permissive of transposition and accumulate copies of particular transposable elements. Overall, it is important to quantify genotype‐specific transposable element dynamics as well as population averages to understand the dynamics of transposable element accumulation over time. 相似文献
5.
Summary Competition for light among species in a mixed canopy can be assessed quantitatively by a simulation model which evaluates the importance of different morphological and photosynthetic characteristics of each species. A model was developed that simulates how the foliage of all species attenuate radiation in the canopy and how much radiation is received by foliage of each species. The model can account for different kinds of foliage (leaf blades, stems, etc.) for each species. The photosynthesis and transpiration for sunlit and shaded foliage of each species is also computed for different layers in the canopy. The model is an extension of previously described single-species canopy photosynthesis simulation models. Model predictions of the fraction of foliage sunlit and interception of light by sunlit and shaded foliage for monoculture and mixed canopies of wheat (Triticum aestivum) and wild oat (Avena fatua) in the field compared very well with measured values. The model was used to calculate light interception and canopy photosynthesis for both species of wheat/wild oat mixtures grown under normal solar and enhanced ultraviolet-B (290–320 nm) radiation (UV-B) in a glasshouse experiment with no root competition. In these experiments, measurements showed that the mixtures receiving enhanced UV-B radiation had a greater proportion of the total foliage area composed of wheat compared to mixtures in the control treatments. The difference in species foliage area and its position in the canopy resulted in a calculated increase in the portion of total canopy radiation interception and photosynthesis by wheat. This, in turn, is consistent with greater canopy biomass of wheat reported in canopies irradiated with supplemental UV-B. 相似文献
6.
Judith Parks 《Ethnic and racial studies》2015,38(1):92-108
The increasing ethnic diversity of the UK has been mirrored by growing public awareness of multicultural issues, alongside developments in academic and government thinking. This paper explores the contested meanings around ethnic identity/ies in community settings, drawing on semi-structured interviews with staff from Children's Centres and allied agencies conducted for a research project that examined the relationship between identity and the participation of parents/carers in services in northeast England. The research found that respondents were unclear about, especially, white ethnic identities, and commonly referred to other social categorizations, such as age, nationality, and circumstances such as mobility, when discussing service users. While in some cases this may have reflected legitimate attempts to resist over-ethnicizing non-ethnic phenomena, such constructions coexisted with assumptions about ethnic difference and how it might translate into service needs. These findings raise important considerations for policy and practice. 相似文献
7.
Jack Fong 《Ethnic and racial studies》2013,36(2):327-357
My paper examines the Karen ethnic nationality and their fifty-eight-year self-determination struggle against ethnic cleansing resulting from the ethnocratic and military governments of Burma. I frame Karen self-determination as a development issue by employing Rodolfo Stavenhagen's ethnodevelopment model. Ethnodevelopment argues that, if asymmetrical development occurs within a multi-ethnic state, state-oriented ethnic minority development strategies are needed to neutralize the asymmetry. However, Stavenhagen's ethnodevelopment does not question the premise of an authoritarian state or the systemic crisis experienced by ethnic minorities under authoritarian rule. Thus, I revise ethnodevelopment from its top-to-bottom trajectory where ethnic minority development is dependent upon the centralized state, to a bottom-to-top trajectory I designate as liberation ethnodevelopment. I argue that Karen liberation ethnodevelopment is also a development process, but one that develops and shields the Karen from ethnic cleansing. 相似文献
8.
ZACHARY I. FELIX YONG WANG CALLIE J. SCHWEITZER 《The Journal of wildlife management》2010,74(3):496-503
ABSTRACT Although effects of forest management on amphibians are relatively well studied, few studies have examined how these practices affect egg deposition by adults, which can impact population recruitment. We quantified the effects of 4 canopy tree-retention treatments on amphibian oviposition patterns in clusters of 60-L aquatic mesocosms located in each treatment. We also related aquatic and terrestrial biophysical parameters in treatment plots to oviposition patterns. Cope's gray treefrogs (Hyla chrysoscelis) deposited more egg masses in clear-cut and 25–50% tree-retention treatments than in controls. In contrast, mountain chorus frogs (Pseudacris brachyp***hona) deposited more egg masses in unharvested control and 75% retention treatments than in clear-cut or 25–50% retention treatments. Spotted salamanders (Ambystoma maculatum) only deposited eggs in 75% retention treatments and controls. The number of egg masses deposited by mountain chorus frogs was positively related to canopy cover and negatively related to water temperature, pH, and dissolved oxygen, whereas we noted the opposite relationships for Cope's gray treefrogs. We did not detect a relationship between the number of egg masses deposited by any species and the distance of mesocosms to either the nearest mature closed-canopy forest or to the nearest natural amphibian breeding pool. The impacts of the silvicultural treatments we studied were species-specific and depended on the amount of trees removed. In areas where protection of spotted salamander and mountain chorus frog breeding habitat is a priority, we recommend harvests retain at least 75% of the canopy. Our results also suggest that retention of 25–50% of canopy trees surrounding amphibian breeding pools has little conservation benefit. 相似文献
9.
定量分析植被冠层对降雨再分配过程的影响,是认识陆地生态系统水文循环的重要环节。然而,由于干旱区天然植被分布稀疏、形态结构特殊,其降雨再分配过程的测算较为困难,相关研究较少,特别是关于荒漠低矮灌丛的降雨再分配研究鲜有报道。本文以河西走廊中段临泽绿洲—荒漠过渡带的天然建群种泡泡刺灌丛(Nitraria sphaerocarpa)为研究对象,基于3年逐个单次降雨事件的观测数据分析了生长季泡泡刺灌丛的降雨再分配特征及主要影响因素,量化了泡泡刺灌丛覆盖下实际进入土壤的有效降雨量及其空间分布特征。结果表明:(1)生长季泡泡刺灌丛的平均穿透率、树干茎流率和冠层截留损失率分别为87.89%、1.61%和10.50%;(2)降雨量是影响泡泡刺灌丛降雨再分配特征的关键气象因素,其与穿透雨量、树干茎流量、冠层截留损失量之间具有显著的统计关系(P<0.001);(3)与干旱区其他稀疏植被相比,泡泡刺灌丛的穿透率和集流率较高,冠层截留损失率较低,与其特殊的植被形态特征有关,相关分析的结果表明,泡泡刺灌丛的穿透雨量与植被面积指数和株高呈显著的负相关关系(P<0.001),树干茎流量与树干倾角呈显著的正... 相似文献
10.
Andropogon gayanus (gamba grass) is an introduced pasture grass that threatens Australia's tropical savannas by modifying fire regimes and species composition. To understand the establishment requirements of A. gayanus, we undertook a field experiment to determine the effect of canopy cover and ground layer disturbance on seedling emergence and survival. Seed was sown under three canopy treatments (undisturbed, artificial canopy gap, and natural canopy gap) and under three ground layer treatments (Control, Vegetation disturbed, and Soil disturbed). Results have shown that A. gayanus can establish and survive regardless of canopy cover or ground disturbance, although such site disturbances will increase establishment success. Disturbance of both the overstorey canopy and the ground layer increased A. gayanus emergence, whereas seedling survival to 12 mo after seed sowing was affected by ground layer disturbance alone. Disturbance of the canopy increased light transmission, which may have promoted germination. Ground layer disturbance may also have increased light transmission and suitable sites for establishment, and reduced competition for resources, such as water and nutrients. The ability of A. gayanus to spread along disturbed areas, establish in relatively undisturbed savannas, and resprout after fire within 6 mo after seedling emergence suggests that this species will become increasingly widespread in Australia's tropical savannas. Its control is urgently required. 相似文献
11.
The fact that the 1991 Census of Population included a race and ethnic question followed evidence from the 1989 test Census that this was not likely to arouse strong public opposition ‐ while the case for race and ethnic data in the Census was overwhelming. This article focuses on the necessity of the data for the proper implementation of the Race Relations Act 1976, especially in relation to employment. It demonstrates how the linking of race and ethnic manpower statistics in the Census to the analysis of local labour‐market areas could provide employers with the means by which they can measure whether or not they are achieving genuine equality of employment opportunity under the 1976 Act. The article illustrates the recommended approach and shows the substantial effect upon the ‘benchmark’ data that results from analysing each major occupation group separately. Finally, the article notes some possible weaknesses in the 1991 Census data that will be available for monitoring equal employment opportunity in Britain. 相似文献
12.
John Solomos 《Ethnic and racial studies》2013,36(2):363-364
I examine how migrant–national encounters are morally framed through boundary making based on intersections of class, sexuality, ethnicity and migrancy. Encounters are a fruitful lens for the study of the everyday politics of diversity and belonging. By focusing on encounters it is possible to analyse whether close contact does in fact reduce prejudice, as has been argued in research on cosmopolitan urbanism. I present the notion of contact space as a conceptual tool for such analysis, as well as examples of contact spaces in the private and public spheres. I use ethnographic data on the employment of domestic workers in Naples, Italy, to show that close contact does not alleviate prejudices in societies that offer little possibility of social advancement for migrant workers. 相似文献
13.
14.
Claire Alexander 《Ethnic and racial studies》2014,37(10):1784-1792
The Empire Strikes Back was a landmark text in the formation and transformation of ethnic and racial studies in Britain. With issues of race, migration, nation and inequality starkly back on the current political and public agenda, this review article reflects on the continued significance of the book's insights and challenges for contemporary race politics in the UK. 相似文献
15.
John C. Kennedy 《Ethnos》2013,78(3-4):5-23
Recent claims to Aboriginal (native or indigenous) identity include new peoples who may not have had an historical consciousness as distinct peoples. This paper presents such a case from Canada, the recent ethnogenesis of the Labrador Metis. These Metis claim Inuit ancestry. Their claim is opposed by Labrador's two established Aboriginal associations and government. Yet Labrador Metis have incorporated under the Labrador Metis Association, filed a land claim with the Canadian government, and are pressing their case before the public. The paper discusses how the Metis are attempting to negotiate Aboriginality, some of the sociocultural consequences of Metis ethnic mobilization, and why Metis are claiming to be Aboriginal at this time. 相似文献
16.
Eric Kaufmann 《Ethnic and racial studies》2013,36(6):1086-1119
This article tries to make the case for a variant of the good life based on a synthesis of liberalism and ethnicity. Liberal communitarianism's treatment of ethnicity tends to fall under the categories of either liberal culturalism or liberal nationalism. Both, it is argued, fail to come to terms with the reality of ethnic community, preferring instead to define ethnicity in an unrealistic, cosmopolitan manner. By contrast, this essay squarely confronts four practices that are central to ethnic communities: symbolic boundary-maintenance; exclusive and inflexible mythomoteurs ; the use of ancestry and race as boundary markers; and the desire among national groups to maintain their ethnic character. This article argues that none of these practices need contravene the tenets of liberalism as long as they are reconstructed so as to minimize entry criteria and decouple national ethnicity from the state. The notion of liberal ethnicity thereby constitutes an important synthesis of liberal and communitarian ends. 相似文献
17.
Contrasting traits,contrasting environments,and considerations on population dynamics under a changing climate: an ecophysiological field study of two co‐dominant tree species
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Edgard A. Bontempo e Silva Kiyomi Ono Akihiro Sumida Shigeru Uemura Toshihiko Hara 《Plant Species Biology》2016,31(1):38-49
The increase in light availability resulting from canopy changes or opening is not always beneficial and can inhibit photosynthesis of tree seedlings already under other environmental stress. Tree seedlings' responses to compounded abiotic stress depend on their life‐history traits, and understanding the variations of such responses is important for understanding population dynamics under a changing climate. In this study we investigate how the photosynthesis of juveniles of two canopy tree species with different life‐history traits, Abies sachalinensis and Betula ermanii, differs in two contrasting sites at a sub‐boreal forest in northern Japan—one under a deciduous canopy (Closed site) and the other at a wide canopy opening (Open site). Seedlings at the Open site had low Fv/Fm (quantum yield of photosystem II) for a longer period than those at the Closed site. Abies sachalinensis at the Closed site showed lower Fv/Fm in spring than those at the Open site, but recovered after the canopy's new leaves flushed, indicating its acclimation to the shaded condition. Mean Pmax (light‐saturated photosynthetic rate at ambient CO2 levels) of A. sachalinensis seedlings was affected by site and air temperature, while B. ermanii seedlings were also affected by precipitation. Only B. ermanii's seedlings presented growth in the period studied, in spite of observed mid‐day drops to Fv/Fm attributed to water‐deficit‐related photoprotection. Results suggest that the climate change predicted for the Hokkaido area may increase the competitive advantage of broad‐leaved deciduous species, such as B. ermanii, in relation to evergreen conifers like A. sachalinensis. 相似文献
18.
Sahar Sadeghi 《Ethnic and racial studies》2013,36(10):1613-1631
The 2015 refugee crisis is at the center of public and political discourse across Europe, especially among nations that have accepted refugees. Utilizing ethnographic fieldwork and 48 in-depth interviews conducted in 2011 and 2016 with Iranians in Hamburg, Germany, this paper considers how the refugee crisis impacts the racial boundaries between Germans and immigrant communities. It details how the crisis has made ethnic nationalism, Islamophobia, anti-foreigner prejudice and racism more pronounced and salient throughout Germany. The interviews demonstrate that this climate affects Iranians in several ways: they cite feeling more threat and stigma, as well as experiences of marginality, perpetual foreignness, and discrimination. This research contributes to sociological scholarship on migration and race by examining how critical international events influence and shape processes of racialization, identity and belonging, and social boundaries and hierarchies. 相似文献
19.
A. Magdalena Hurtado Carol A. Lambourne Kim R. Hill Karen Kessler 《Human nature (Hawthorne, N.Y.)》2006,17(2):129-154
The socioeconomic and ethnic characteristics of parents are some of the most important correlates of adverse health outcomes
in childhood. However, the relationships between ethnic, economic, and behavioral factors and the health outcomes responsible
for this pervasive finding have not been specified in child health epidemiology. The general objective of this paper is to
propose a theoretical approach to the study of maternal behaviors and child health in diverse ethnic and socioeconomic environments.
The specific aims are: (a) to describe a causal pathway between the utility that women obtain through work outside the home and through child care
and disease hazard rates in childhood using an optimization model; (b) to specify the influence of ethnic and socioeconomic factors on model constraints; (c) to use the model as a tool to learn about how different combinations of maternal wage labor and child care time might influence
child health outcomes in diverse social contexts; (d) to identify parameters that will require measurement in future research; (e) to discuss research strategies that will enable us to obtain these measurements; and (f) to discuss the implications of the model for biostatistical modeling and public health intervention. Optimization models
are powerful heuristic tools for understanding how ethnic, environmental, family, and personal characteristics can place important
constraints on both the quality and quantity of care that women can provide to their children. They provide a quantitative
appreciation for the difficult trade-offs that most women face between working in order to purchase basic goods that children
cannot do without (e.g., food, clothing, shelter, health insurance), and increasing offspring well-being through child care
(e.g., training in social skills, affection, protection from environmental hazards, help with homework).
The research was funded by a Faculty Scholars Award from the William T. Grant Foundation to A. Magdalena Hurtado.
A. Magdalena Hurtado, Ph.D., is an associate professor in the Department of Anthropology, University of New Mexico. Her research
interests include the origins of the sexual division of labor, epidemiology of indigenous peoples, disease susceptibility,
the development and intergenerational transmission of antigens and immune defense, immune function and allergic sensitization,
and trauma. She also works on public health interventions, biological capital and poverty, and land tenure and human rights
in native communities of South America.
Carol Lambourne, M.Sc., is a doctoral candidate in the Department of Anthropology, University of New Mexico. Her research
interests are evolutionary models of child and adolescent development, life history theory, family composition and investment
patterns, pubertal timing and psychosexual maturation, juvenile stress, and infanticide.
Kim Hill, Ph.D., is a professor in the Department of Anthropology, University of New Mexico. His research interests are modern
hunter-gatherers, including extensive fieldwork in lowland South America. Current topics of interest include human evolution,
economic strategies, life history theory, the evolution of cooperation, and the emergence of social norms enforced by punishment.
He is also involved in economic development, health and education projects with lowland South American native populations.
Karen Kessler received her M.S. in Anthropology from the University of New Mexico in 1996. Her research interests are the
application of mathematical modeling to the prevention of diabetes and other causes of morbidity and mortality in historical
populations. 相似文献
20.
This paper contributes to the literature on how perceived discrimination influences the impact of intergroup contact among ethnic minority members. Previous research has shown that perceived group discrimination inhibits the positive outcomes of intergroup contact among ethnic minority members. In extension, this paper examines whether perceived personal discrimination has a similar negative impact as a boundary condition of the contact–prejudice relationship among ethnic minority members. Analyses expand previous intergroup contact research by showing that the impact of intergroup contact is uniform across various levels of perceived personal discrimination. This finding suggests that the otherwise harmful consequences of perceived personal discrimination can be effectively counterbalanced by positive contact experiences among ethnic minority members. Analyses use evidence from a national probability sample, which was fielded in 2006 to examine some of the largest ethnic minority groups (N?=?3,462). The concluding section discusses the theoretical implications of the empirical findings. 相似文献