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1.
The value of intra- and interracial populations in common bean (Phaseolus vulgaris L.) needs to be determined in order to create useful genetic variation for maximizing gains from selection, broadening the genetic base of commercial cultivars, and making efficient use of available resources. Five large-seeded parents of race Nueva Granada (N), two small-seeded race Mesoamerica (M), and one medium-seeded race Durango (D) were hybridized to produce one intraracial (N x N) and three interracial (two N x M and one N x D) populations. Seventy-nine F2-derived F6 lines randomly taken from each population along with their parents were evaluated for agronomic traits and markers at Palmira and Popayán, Colombia, in 1990 and 1991. Variation for agronomic traits and for morphological, protein, and isozyme markers was larger in interracial populations than in the intraracial population. Mean seed yield of all lines as well as yield of the highest yielding line from two interracial populations were significantly higher than that of the intraracial population. The highest ( 0.80±0.15) heritability was recorded for 100-seed weight. Values for seed yield varied from 0.19±0.17 to 0.50±0.16. Gains from selection (at 20% selection pressure) for seed yield ranged from 3.9% to 11.4%. Seed yield was positively associated with biomass yield, pods/m2, and days to maturity, but harvest index showed negative correlations with these traits and a positive value with 100-seed weight. Polymorphism was recorded for phaseolin, lectins, protein Group-1 and protein Group-2 fractions, and six isozyme loci. Lines with indeterminate growth habit had significantly (P < 0.01) higher seed yield than lines with determinate growth habit in a Redkloud x MAM 4 population. Also, 23 other associations of markers with agronomic traits other than seed yield were recorded. Of these associations, lines with T phaseolin, the Diap1 2 allele, and lilac flower color tended to possess greater seed weight.  相似文献   

2.
In this paper we bring together the literatures on frame analysis, the meaning of race and campus racial climate to analyse the race frames – lenses through which individuals understand the role of race in society – held by white students attending elite US universities. For most, the elite university experience coincides with a strengthening or emergence of the diversity frame, which emphasizes the positive benefits of cultural diversity. Still, many also hold a colour-blind frame, which sees race groups as equivalent and racial identities as insignificant. We highlight the ambivalence that these divergent frames create for student perspectives on affirmative action and interracial contact on campus. Our findings demonstrate the mutability of race frames. We also highlight the impact that institutions may have on individuals' race frames. The paper is based on in-depth interviews with forty-seven US-born white undergraduates attending Brown University and Harvard University.  相似文献   

3.
I respond to a review by C. Matthew Snipp, revisiting how my book connects abolitionist leanings to acceptance of racial mixing in the Early Republic. I reiterate that, contrary to the reviewer's claims, the book does not suggest that the defence of interracial marriage has been a thriving social movement. I correct his reading of my chapter on the Civil War era, referring to both the variety of voices present, and the claims of reformers' opponents, who were the only ones who claimed racial mixing was an aim of the abolitionist movement. Lastly, I defend The United States of the United Races against Professor Snipp's characterization of it as a work anticipating a ‘post-racial’ ideal, embodied by racially mixed people, who would be the end point of the obsolescence of race as a relevant analytic tool.  相似文献   

4.
The racial and ethnic makeup of the United States has become increasingly diverse over the past few decades. Growing rates of interracial dating and marriage have led to an increasing number of biracial individuals. Despite increasing rates of biracial individuals, research on this population specifically in relation to dating preferences, remains limited in scope. In order to assess biracial individuals' romantic partner preferences, the present research examines 1,203 Internet dating profiles drawn from Match.com. This study utilizes logistic regression to examine the willingness of biracial individuals to cross the colour line when seeking a potential romantic partner. The findings suggest that there are distinct racial dating preferences that reflect the presence of a triracial hierarchy. These results are examined in relation to how identity formation and racial stratification may play a part in shaping the racial/ethnic dating preferences of biracial individuals.  相似文献   

5.
This paper speaks against tolerance as an instrument of institutionalized anti-racism within academia where collegiality is a minimal expectation in interpersonal interactions. Through auto-ethnographic readings, the discussion focuses on the racial affective economies produced in universities as tolerance ‘makes race ordinary’. Within this reading, ‘making race ordinary’ is shown to produce unliveable lives because of its racial affective economies animated by contemptuous tolerance, disgust and disattendability. These negative affects emerge within the epistemology of ignorance produced by the racial contract and have affective and career consequences for racialized others placed outside of organizational networks. The paper argues that to destabilize the white power in networks that decide on access, tenure and promotion and to enable liveable lives within universities, the transformative potential of the transracial intimacy of friendship must be engaged. This entails ‘race made ordinary’ through disalienation-estrangement from the ‘raced’ subject positionings of the racial contract.  相似文献   

6.
Early research on black racial identity development cautioned that close relationships with whites signalled an alienation from blackness and a subconscious acceptance that ‘white is right’. These assumptions mirrored popular media and political discourse suggesting that romantic relationships outside of one's racial group reflect a devalued or inauthentic racial self. More recent scholarly research presents a mixed picture about the role of interracial intimacy on black racial identities. Using in-depth qualitative narratives with forty-two interracially partnered African Americans, this article explores whether interracial intimacy recasts the meaning or intensity of black racial identities. Findings affirm that black racial identities are heterogeneous – some partners experienced blackness as a central, fundamental identity while others possessed ambivalent attachments to blackness. Across these experiences, however, adult interracial intimacy had at most an incremental influence on racial identity. Interracial contact during adolescence was far more influential because it allowed blacks to develop dimensions of white cultural identity.  相似文献   

7.
I examine an understudied topic of intermarriage – nonwhite mixed unions. Drawing on a study of second-generation Filipino Americans, I compare how respondents in inter-ethnic (those partnered with other Asians) and nonwhite interracial (i.e. Latino, black, and non-Asian bi-racial) unions perceive racial boundaries, or their ‘racial schemas’. I argue that mixed unions can change how partners view racial boundaries. Drawing on phenotype, culture, and power position, both inter-ethnically and nonwhite interracially partnered respondents viewed themselves as different from whites. However, they differed in how they constructed nonwhite boundaries. Respondents in inter-ethnic unions drew on their Asian identity to distinguish themselves from Latinos and blacks, while informants in nonwhite interracial unions highlighted their Filipino identity to distance themselves from East Asians and align themselves with Latinos and blacks. These findings show that marriage affects racial boundary development and that mixed unions impact individuals’ racial incorporation.  相似文献   

8.
Abstract

Are predictions that Hispanics will make up 25 per cent of the US population in 2050 reliable? The authors of this paper argue that these and other predictions are problematic insofar as they do not account for the volatile nature of Latino racial and ethnic identifications. In this light, the authors propose a theoretical framework that can be used to predict Latinos’ and Latinas’ racial choices. This framework is tested using two distinct datasets – the 1989 Latino National Political Survey and the 2002 National Survey of Latinos. The results from the analyses of both of these surveys lend credence to the authors’ claims that Latinas’ and Latinos’ skin colour and experiences of discrimination affect whether people from Latin America and their descendants who live in the US will choose to identify racially as black, white or Latina/o.  相似文献   

9.
ABSTRACT

How should we understand the conundrum of love for the segregated school – a system built to keep you in your place? In Gone Home. Race and Roots through Appalachia, Karida L. Brown looks at African American teacher’s work in segregated schools and shows how desegregation could be felt in both gains and losses in the black community. Those teachers prepared their students for a world of integration without freedom. This essay proposes a counter-memory of segregation, a relational agency of teachers past that remains to this day. Former students’ commemoration of teachers, principals, and schools dating from the time of institutionalized racial exclusion works as a symbolic reminder in a still-racist world, representing not only the need to be prepared, but also to stay prepared.  相似文献   

10.
Sexual harassment has traditionally been studied as men's harassment of women. This has led to a lack of knowledge about same sex harassment, and women harassing peers. This has also downplayed the inherent sexual nature of sexual harassment acts. While keeping in mind that sexual harassment is undesirable and causes distress, one needs to consider that many acts that are perceived as unwanted may not primarily be motivated by a wish to derogate but rather by an interest in soliciting short-term sex. In the current study we examined both perpetrators as well as victims of harassment, and specified both sex of perpetrator and target (a total of eight sex constellations). We reproduced the previously found association between unrestricted sociosexuality and sexual harassment in a representative sample of 1326 high school students (57% women). In all regression models sociosexuality outcompeted traditional measures such as porn exposure, rape stereotypes and hostile sexism. Based on the original work we divided the harassment acts into two groups of tactics: sexual solicitation and competitor derogation. Men were particularly subject to derogatory tactics from other men, while women were particularly subject to solicitation from opposite sex peers. Sexual harassment may be understood better from a human sexual strategies perspective, including competitor derogation and mate solicitation. As such, sociosexual orientation predicts both same sex derogation and opposite sex solicitation. The current results highlight the importance of considering the sex of both perpetrator and target. This advanced understanding of the inherently sexual nature of sexual harassment needs to inform future prevention studies. Unrestricted sociosexuality predicts sexual harassment in all constellations better than traditional social science models.  相似文献   

11.
Undergraduates at elite universities in the US and UK are, according to Dr Warikoo, conflicted about the relation of racial diversity to meritocracy. In the US, white students view racial minorities as academically less qualified but as providing a diversity benefit; UK students view minorities as equal members of a meritocracy but turn a blind eye to racial disparities on and off campus. What Warikoo’s narrative overlooks is the role played by differences between the US and the UK in the educational paths and testing regimes that produce these disparate mentalities. Although 40 per cent of America’s colleges offer test-optional admissions, some like Harvard still require SAT/ACT scores. The SAT/ACT are predictively weak and biased, stigmatizing minorities as underperformers. Test biases and the predictive superiority of high school grades are not widely understood. Warikoo’s proposal to blow up meritocracy with an admissions lottery is to be applauded.  相似文献   

12.
Existing and alternative policy towards the Arabs in Israel*   总被引:1,自引:0,他引:1  
Definitions of racial harassment adopting symmetrical and asymmetrical perspectives are reviewed, and the term ‘racist harassment’ is proposed. The Glasgow study of harassment adopted a combined statistical and case‐study approach. Black experiences of racist harassment in Glasgow in 1988 are documented through the presentation of survey results. The Housing Department recognized harassment, but its active response was confused. Transfer of victims and action against perpetrators are discussed. None of three case‐studies extracted from Housing Department files was satisfactorily resolved. Other cities show alternative, effective responses. Racism in Scotland, both interpersonal and institutional, is examined. In Glasgow, we conclude, racism creates interpersonal harassment and an institutional failure to respond.  相似文献   

13.
Across sexually reproducing species, males and females are in conflict over the control of reproduction. At the heart of this conflict in a number of taxa is male harassment of females for mating opportunities and female strategies to avoid this harassment. One neglected consequence that may result from sexual harassment is the disruption of important social associations. Here, we experimentally manipulate the degree of sexual harassment that wild female guppies (Poecilia reticulata) experience by establishing replicated, semi-natural pools with different population sex ratios. We quantify the effects of sexual harassment on female social structure and the development of social recognition among females. When exposed to sexual harassment, we found that females had more disparate social networks with limited repeated interactions when compared to females that did not experience male harassment. Furthermore, females that did not experience harassment developed social recognition with familiar individuals over an 8-day period, whereas females that experienced harassment did not, an effect we suggest is due to disruption of association patterns. These results show that social network structure and social recognition can be affected by sexual harassment, an effect that will be relevant across taxonomic groups and that we predict will have fitness consequences for females.  相似文献   

14.
The study investigates assortative mating patterns with respect to race (visible minority status) in Canada. Using the 2001 Census data, the article analyses the occurrence of White/non-White unions in Montreal, Toronto and Vancouver. Log-linear models indicate that the relative levels of interracial relationships vary across racial groups, immigration status, and place of residence. First, the highest odds of cohabiting or marrying a White person are found among Blacks. Whereas the high level of racial exogamy of Blacks is observed in all metropolitan areas under study, the relative position of other groups varies. Second, the highest levels of racial exogamy are found among couples composed of an immigrant and a non-immigrant but this effect varies across racial groups. Third, our hypothesis that residents of Montreal (Quebec) will inter-partner less was confirmed only for unions between two native-born Canadians. Finally, we found that French Canadians are not more inclusive of their linguistic counterparts than Anglophones.  相似文献   

15.
The South Africa’s democratic nation-building programme has sought to encourage a new non-racial nationalism. Over the last thirty years, racial divisions have lessened as the country has successfully consolidated a new democratic political system. However, interracial animosity and a sense of interracial competition continue to characterize many aspects of everyday life. Does this sense of interracial competition have an association with the emergence of widespread xenophobic sentiment in the country? Using the 2013 South African Social Attitudes Survey, a nationally representative survey, this paper will investigate determinants of anti-immigrants attitudes. The results show that anti-immigrant sentiment is linked to a sense of interracial competition and alienation. A belief that immigrants were beneficial to society was also strongly (and negatively) correlated with attitudes towards immigrants. These results suggest that reducing xenophobia in the country should be seen as part of a larger project of promoting social-cultural cohesion in the country.  相似文献   

16.
Given their importance in shaping social networks and determining how information or transmissible diseases propagate in a population, interactions between individuals are the subject of many data collection efforts. To this aim, different methods are commonly used, ranging from diaries and surveys to decentralised infrastructures based on wearable sensors. These methods have each advantages and limitations but are rarely compared in a given setting. Moreover, as surveys targeting friendship relations might suffer less from memory biases than contact diaries, it is interesting to explore how actual contact patterns occurring in day-to-day life compare with friendship relations and with online social links. Here we make progresses in these directions by leveraging data collected in a French high school and concerning (i) face-to-face contacts measured by two concurrent methods, namely wearable sensors and contact diaries, (ii) self-reported friendship surveys, and (iii) online social links. We compare the resulting data sets and find that most short contacts are not reported in diaries while long contacts have a large reporting probability, and that the durations of contacts tend to be overestimated in the diaries. Moreover, measured contacts corresponding to reported friendship can have durations of any length but all long contacts do correspond to a reported friendship. On the contrary, online links that are not also reported in the friendship survey correspond to short face-to-face contacts, highlighting the difference of nature between reported friendships and online links. Diaries and surveys suffer moreover from a low sampling rate, as many students did not fill them, showing that the sensor-based platform had a higher acceptability. We also show that, despite the biases of diaries and surveys, the overall structure of the contact network, as quantified by the mixing patterns between classes, is correctly captured by both networks of self-reported contacts and of friendships, and we investigate the correlations between the number of neighbors of individuals in the three networks. Overall, diaries and surveys tend to yield a correct picture of the global structural organization of the contact network, albeit with much less links, and give access to a sort of backbone of the contact network corresponding to the strongest links, i.e., the contacts of longest cumulative durations.  相似文献   

17.
The friendship paradox is the phenomenon that in social networks, people on average have fewer friends than their friends do. The generalized friendship paradox is an extension to attributes other than the number of friends. The friendship paradox and its generalized version have gathered recent attention due to the information they provide about network structure and local inequalities. In this paper, we propose several measures of nodal qualities which capture different aspects of their activities and influence in online social networks. Using these measures we analyse the prevalence of the generalized friendship paradox over Twitter and we report high levels of prevalence (up to over 90% of nodes). We contend that this prevalence of the friendship paradox and its generalized version arise because of the hierarchical nature of the connections in the network. This hierarchy is nested as opposed to being star-like. We conclude that these paradoxes are collective phenomena not created merely by a minority of well-connected or high-attribute nodes. Moreover, our results show that a large fraction of individuals can experience the generalized friendship paradox even in the absence of a significant correlation between degrees and attributes.  相似文献   

18.
In this article we describe the results of a comparative case study of two inner-city high schools located in the southeastern United States. One school, a citywide school with high admission standards, enrolls an all-African American lower-to-middle-class population. The other school enrolls a more ethnically and racially diverse population of students from a single lower-class neighborhood. Using Grossberg's notion of identity politics, we describe how students' racial/ ethnic identity to a greater or lesser degree becomes both a means of resistance and accommodation to white hegemony.  相似文献   

19.
20.
Abstract

The increasing diversity of the US population has stimulated interest in racial identification, which is complex for phenotypically heterogeneous groups such as Puerto Ricans. We overcome several limitations of the empirical literature on racial identification among Puerto Ricans with a study that is grounded in the experience of Puerto Rican women in New York City. Our analysis focuses on two questions: How do Puerto Rican women in New York identify themselves racially? What are the sources of racial identification? The results indicate that most Puerto Rican women in New York conflate race and ethnicity by designating their race as either ‘Puerto Rican’ or ‘Hispanic’. Moreover, the decision to ‘become’ pan-ethnic has complex roots. In particular, the effect of skin tone on pan-ethnic identification is conditioned by socioeconomic and neighbourhood characteristics.  相似文献   

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