The psychology of diaspora experiences: intergroup contact, perceived discrimination, and the ethnic identity of Koreans in China.

Science.gov (United States)

Lee, Richard M; Noh, Chi-Young; Yoo, Hyung Chol; Doh, Hyun-Sim

2007-04-01

The moderating role of intergroup contact on the relationship between perceived discrimination and ethnic identity was examined in a diaspora community of Koreans living in China. It was hypothesized that Koreans with higher intergroup contact would have a lower ethnic identity under higher discrimination, whereas Koreans with lower intergroup contact would have a higher ethnic identity. Across two separate college samples, Koreans who were more willing to interact with Han Chinese had a lower ethnic identity when discrimination was higher, but this finding was not replicated within one college setting. These findings challenge the linear rejection-identification model and suggest displaced people may minimize ingroup-outgroup differences, depending on their willingness to seek intergroup contact. (c) 2007 APA, all rights reserved.

Intergroup Contact is Related to Evaluations of Interracial Peer Exclusion in African American Students.

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Ruck, Martin D; Park, Henry; Crystal, David S; Killen, Melanie

2015-06-01

There are few published studies on the influence of intergroup contact on ethnic minority public school students' evaluations of interracial exclusion. In this study, African American children and adolescents (N = 158, 4th, 7th, and 10th grade; 67.1%) were individually interviewed regarding peer exclusion for scenarios depicting cross-race peer exclusion in various contexts. The level of positive intergroup contact, attribution of motives for exclusion, wrongfulness ratings, reasoning about exclusion, estimations of the frequency of exclusion, and awareness of the use of stereotypes to justify racial exclusion were assessed. Intergroup contact was significantly related to attributions of racial motives, higher ratings of wrongfulness, greater use of moral reasoning, and higher estimations of the frequency of exclusion. In addition to context effects, with increasing grade participants were more likely to refer to the historical and social circumstances contributing to the manifestation of racial stereotypes used to justify exclusion. The findings are discussed in terms of the existing research on intergroup relations and evaluations of social exclusion.

Does social deprivation influence inter-group contact outcomes for pupils in Northern Ireland?

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Joanne Hughes

2015-02-01

Full Text Available The education system in Northern Ireland is characterized by division, with around 95% of the pupil population attending predominantly co-religionist schools. In a society that is transitioning from a thirty year conflict that has been framed by hostilities between the main Catholic and Protestant communities, reconciliation interventions in education have sought to promote the value of intergroup contact between pupils attending separate schools. Some qualitative research suggests that such initiatives are more likely to have positive outcomes for pupils from more middle class backgrounds than those from more disadvantaged communities and areas that experienced high levels of conflict related incidents and deaths during the pre-ceasefire years. Drawing on contact theory and empirical evidence from a large scale quantitative study, we seek to examine this theory. Using free school meals as a proxy for social class, our findings are consistent in finding that there is a differential impact of contact for those from less affluent backgrounds, and we conclude by arguing that this should be reflected in policy responses.

Perspective-taking increases willingness to engage in intergroup contact.

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Wang, Cynthia S; Kenneth, Tai; Ku, Gillian; Galinsky, Adam D

2014-01-01

The current research explored whether perspective-taking increases willingness to engage in contact with stereotyped outgroup members. Across three studies, we find that perspective-taking increases willingness to engage in contact with negatively-stereotyped targets. In Study 1, perspective-takers sat closer to, whereas stereotype suppressors sat further from, a hooligan compared to control participants. In Study 2, individual differences in perspective-taking tendencies predicted individuals' willingness to engage in contact with a hooligan, having effects above and beyond those of empathic concern. Finally, Study 3 demonstrated that perspective-taking's effects on intergroup contact extend to the target's group (i.e., another homeless man), but not to other outgroups (i.e., a man of African descent). Consistent with other perspective-taking research, our findings show that perspective-taking facilitates the creation of social bonds by increasing contact with stereotyped outgroup members.

Perspective-Taking Increases Willingness to Engage in Intergroup Contact

Science.gov (United States)

Wang, Cynthia S.; Kenneth, Tai; Ku, Gillian; Galinsky, Adam D.

2014-01-01

The current research explored whether perspective-taking increases willingness to engage in contact with stereotyped outgroup members. Across three studies, we find that perspective-taking increases willingness to engage in contact with negatively-stereotyped targets. In Study 1, perspective-takers sat closer to, whereas stereotype suppressors sat further from, a hooligan compared to control participants. In Study 2, individual differences in perspective-taking tendencies predicted individuals' willingness to engage in contact with a hooligan, having effects above and beyond those of empathic concern. Finally, Study 3 demonstrated that perspective-taking's effects on intergroup contact extend to the target's group (i.e., another homeless man), but not to other outgroups (i.e., a man of African descent). Consistent with other perspective-taking research, our findings show that perspective-taking facilitates the creation of social bonds by increasing contact with stereotyped outgroup members. PMID:24465648

The Joint Effect of Bias Awareness and Self-Reported Prejudice on Intergroup Anxiety and Intentions for Intergroup Contact

Science.gov (United States)

Perry, Sylvia P.; Dovidio, John F.; Murphy, Mary C.; van Ryn, Michelle

2015-01-01

Two correlational studies investigated the joint effect of Bias Awareness—a new individual difference measure that assesses Whites’ awareness and concern about their propensity to be biased—and prejudice on Whites’ intergroup anxiety and intended intergroup contact. Using a community sample (Study 1), we found the predicted Bias Awareness × Prejudice interaction. Prejudice was more strongly related to interracial anxiety among those high (vs. low) in Bias Awareness. Study 2 investigated potential behavioral consequences in an important real world context: medical students’ intentions for working primarily with minority patients. Study 2 replicated the Bias Awareness × Prejudice interaction and further demonstrated that interracial anxiety mediated medical students’ intentions to work with minority populations. PMID:25111552

Perspective-taking increases willingness to engage in intergroup contact.

Directory of Open Access Journals (Sweden)

Cynthia S Wang

Full Text Available The current research explored whether perspective-taking increases willingness to engage in contact with stereotyped outgroup members. Across three studies, we find that perspective-taking increases willingness to engage in contact with negatively-stereotyped targets. In Study 1, perspective-takers sat closer to, whereas stereotype suppressors sat further from, a hooligan compared to control participants. In Study 2, individual differences in perspective-taking tendencies predicted individuals' willingness to engage in contact with a hooligan, having effects above and beyond those of empathic concern. Finally, Study 3 demonstrated that perspective-taking's effects on intergroup contact extend to the target's group (i.e., another homeless man, but not to other outgroups (i.e., a man of African descent. Consistent with other perspective-taking research, our findings show that perspective-taking facilitates the creation of social bonds by increasing contact with stereotyped outgroup members.

The joint effect of bias awareness and self-reported prejudice on intergroup anxiety and intentions for intergroup contact.

Science.gov (United States)

Perry, Sylvia P; Dovidio, John F; Murphy, Mary C; van Ryn, Michelle

2015-01-01

Two correlational studies investigated the joint effect of bias awareness-a new individual difference measure that assesses Whites' awareness and concern about their propensity to be biased-and prejudice on Whites' intergroup anxiety and intended intergroup contact. Using a community sample (Study 1), we found the predicted Bias Awareness × Prejudice interaction. Prejudice was more strongly related to interracial anxiety among those high (vs. low) in bias awareness. Study 2 investigated potential behavioral consequences in an important real world context: medical students' intentions for working primarily with minority patients. Study 2 replicated the Bias Awareness × Prejudice interaction and further demonstrated that interracial anxiety mediated medical students' intentions to work with minority populations. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

Patterns of Intergroup Contact in Public Spaces: Micro-Ecology of Segregation in Australian Communities

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Naomi Priest

2014-01-01

Full Text Available The use of public spaces can promote social cohesion and facilitate interpersonal interactions within the community. However, the ways racial and ethnic groups interact in public spaces can also reflect and influence informal segregation in the wider community. The present study aimed to examine patterns of intergroup contact within public spaces in Victoria, Australia through short-term observation in four localities. Data were collected on within-group, intergroup and absence of contact for people from minority and majority groups. A total of 974 contacts were observed. Findings indicate that in the observed public spaces, people from visible minority groups tended to have no contact with others or to interact with people from other ethnic/racial groups. In contrast, those from the majority group tended to interact predominately with other majority group members. This suggests that majority group members are more likely to ‘self-segregate’ in public spaces than those from minority groups.

Intergroup Contact Effects via Ingroup Distancing among Majority and Minority Groups: Moderation by Social Dominance Orientation.

Science.gov (United States)

Kauff, Mathias; Schmid, Katharina; Lolliot, Simon; Al Ramiah, Ananthi; Hewstone, Miles

2016-01-01

Five studies tested whether intergroup contact reduces negative outgroup attitudes through a process of ingroup distancing. Based on the deprovincialization hypothesis and Social Dominance Theory, we hypothesized that the indirect effect of cross-group friendship on outgroup attitudes via reduced ingroup identification is moderated by individuals' Social Dominance Orientation (SDO), and occurs only for members of high status majority groups. We tested these predictions in three different intergroup contexts, involving conflictual relations between social groups in Germany (Study 1; N = 150; longitudinal Study 2: N = 753), Northern Ireland (Study 3: N = 160; Study 4: N = 1,948), and England (Study 5; N = 594). Cross-group friendship was associated with reduced ingroup identification and the link between reduced ingroup identification and improved outgroup attitudes was moderated by SDO (the indirect effect of cross-group friendship on outgroup attitudes via reduced ingroup only occurred for individuals scoring high, but not low, in SDO). Although there was a consistent moderating effect of SDO in high-status majority groups (Studies 1-5), but not low-status minority groups (Studies 3, 4, and 5), the interaction by SDO was not reliably stronger in high- than low-status groups. Findings are discussed in terms of better understanding deprovincialization effects of contact.

Intergroup Contact Effects via Ingroup Distancing among Majority and Minority Groups: Moderation by Social Dominance Orientation.

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Mathias Kauff

Full Text Available Five studies tested whether intergroup contact reduces negative outgroup attitudes through a process of ingroup distancing. Based on the deprovincialization hypothesis and Social Dominance Theory, we hypothesized that the indirect effect of cross-group friendship on outgroup attitudes via reduced ingroup identification is moderated by individuals' Social Dominance Orientation (SDO, and occurs only for members of high status majority groups. We tested these predictions in three different intergroup contexts, involving conflictual relations between social groups in Germany (Study 1; N = 150; longitudinal Study 2: N = 753, Northern Ireland (Study 3: N = 160; Study 4: N = 1,948, and England (Study 5; N = 594. Cross-group friendship was associated with reduced ingroup identification and the link between reduced ingroup identification and improved outgroup attitudes was moderated by SDO (the indirect effect of cross-group friendship on outgroup attitudes via reduced ingroup only occurred for individuals scoring high, but not low, in SDO. Although there was a consistent moderating effect of SDO in high-status majority groups (Studies 1-5, but not low-status minority groups (Studies 3, 4, and 5, the interaction by SDO was not reliably stronger in high- than low-status groups. Findings are discussed in terms of better understanding deprovincialization effects of contact.

Status-Based Asymmetry in Intergroup Responses: Implications for Intergroup Reconciliation

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Malloy, Thomas E.; Ristikari, Tiina; Berrios-Candelaria, Rosalie; Lewis, Beth; Agatstein, Fredric

2011-01-01

We studied intergroup responses as a function of relative intergroup status and familiarity. In Study 1, 34 African Americans and 34 European Americans interacted with two members of the out-group in separate, 20 minute dyadic interactions. Intergroup perception, affect, and behavior were asymmetric; Blacks differentiated the traits of and the quality of interactions with Whites, whereas Whites did not make these differentiations. Blacks and Whites predicted that different out-group partners perceived them similarly. Study 2 showed that the failure to differentiate an out-group member is due to intergroup status differences. Asymmetric intergroup responses pose a barrier to intergroup reconciliation and explain, in part, why increased interracial contact has not eradicated disparities in life outcomes for Black Americans. PMID:21341895

Comparing intergroup contact effects on blatant and subtle prejudice in adolescents: a multivariate multilevel model.

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Herrero Olaizola, Juan; Rodríguez Díaz, Francisco Javier; Musitu Ochoa, Gonzalo

2014-01-01

The literature has rarely paid attention to the differential influence of intergroup contact on subtle and blatant prejudice. In this study, we hypothesized that the influence of intergroup contact on subtle prejudice will be smaller than its influence on blatant prejudice. This hypothesis was tested with data from a cross-sectional design on 1,655 school-aged native Spanish adolescents. Prejudice was measured with a shortened version of the Meertens and Pettigrew scale of blatant and subtle prejudice adapted to Spanish adolescent population. Results from multivariate multilevel analyses for correlated outcome variables supported the hypothesis. Students tended to score higher on the subtle prejudice scale; contact with the outgroup was statistically related both to levels of blatant and subtle prejudice; and, the negative relationship of contact with the outgroup and prejudice is greater for blatant prejudice as compared to subtle prejudice. Overall, results provide statistical evidence supporting the greater resistance to change of subtle forms of prejudice.

Are diverse societies less cohesive? Testing contact and mediated contact theories.

Science.gov (United States)

McKenna, Sarah; Lee, Eunro; Klik, Kathleen A; Markus, Andrew; Hewstone, Miles; Reynolds, Katherine J

2018-01-01

Previous research has demonstrated that there is a negative relationship between ethnic diversity in a local community and social cohesion. Often the way social cohesion is assessed, though, varies across studies and only some aspects of the construct are included (e.g., trust). The current research explores the relationship between diversity and social cohesion across a number of indicators of social cohesion including neighbourhood social capital, safety, belonging, generalized trust, and volunteering. Furthermore, social psychological theories concerning the role of positive contact and its impact on feelings of threat are investigated. Using a sample of 1070 third generation 'majority' Australians and structural equation modelling (SEM), findings suggest ethnic diversity is related to positive intergroup contact, and that contact showed beneficial impacts for some indicators of social cohesion both directly and indirectly through reducing perceived threat. When interethnic contact and perceived threat are included in the model there is no direct negative effect between diversity and social cohesion. The theoretical implications of these findings are outlined including the importance of facilitating opportunities for positive contact in diverse communities.

Ethnic Self-Esteem and Intergroup Attitudes Among the Estonian Majority and the non-Estonian Minority

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Maaris Raudsepp

2009-11-01

Full Text Available The study was focussed on the relationships between ethnic self-esteem and various indicators of intergroup attitudes in a representative sample of adult population of Estonia (N=1142. Attitudinal variables that discriminated most between persons with high and low ethnic self-esteem were identified. Among Estonians ethnic self-esteem was related to positive ingroup bias, readiness for outgroup contact, perceived threat from the outgroup, attitudes to non-Estonian minority, and attitudes toward minority integration. Among non-Estonians ethnic self-esteem was related to readiness for outgroup contact, ethnic sterotypes, and various attitudes towards minority integration. An attempt was made to reconstruct the system of intergroup attidues of prototypical persons with high and low ethnic selfesteem and to describe psychological implications of high and low ethnic self-esteem for members of majority and minority groups. Various theoretical models (social identity theory, integrated threat theory, social dominane theory were used for interpretation of the results.

Intergroup leadership in organizations: Leading across group and organizational boundaries

NARCIS (Netherlands)

M.A. Hogg (Michael); D.L. van Knippenberg (Daan); D.E. Rast III (David)

2012-01-01

textabstractIntergroup leadership-leadership of collaborative performance of different organizational groups or organizations-is associated with unique intergroup challenges that are not addressed by traditional leadership theories. To address this lacuna, we describe a theory of intergroup

Languages of borderlands, borders of languages: Native and foreign language use in intergroup contact between Czechs and their neighbours

Czech Academy of Sciences Publication Activity Database

Petrjánošová, M.; Leix, Alicja

2013-01-01

Roč. 23, č. 4 (2013), s. 658-679 ISSN 1210-3055 R&D Projects: GA ČR GA13-25656S Institutional support: RVO:68081740 Keywords : native language * foreign language * intergroup contact Subject RIV: AN - Psychology

Specific emotions as mediators of the effect of intergroup contact on prejudice: findings across multiple participant and target groups.

Science.gov (United States)

Seger, Charles R; Banerji, Ishani; Park, Sang Hee; Smith, Eliot R; Mackie, Diane M

2017-08-01

Emotions are increasingly being recognised as important aspects of prejudice and intergroup behaviour. Specifically, emotional mediators play a key role in the process by which intergroup contact reduces prejudice towards outgroups. However, which particular emotions are most important for prejudice reduction, as well as the consistency and generality of emotion-prejudice relations across different in-group-out-group relations, remain uncertain. To address these issues, in Study 1 we examined six distinct positive and negative emotions as mediators of the contact-prejudice relations using representative samples of U.S. White, Black, and Asian American respondents (N = 639). Admiration and anger (but not other emotions) were significant mediators of the effects of previous contact on prejudice, consistently across different perceiver and target ethnic groups. Study 2 examined the same relations with student participants and gay men as the out-group. Admiration and disgust mediated the effect of past contact on attitude. The findings confirm that not only negative emotions (anger or disgust, based on the specific types of threat perceived to be posed by an out-group), but also positive, status- and esteem-related emotions (admiration) mediate effects of contact on prejudice, robustly across several different respondent and target groups.

Intergroup Relations in Integrated Schools: A Glimpse inside Interdistrict Magnet Schools

Science.gov (United States)

Bifulco, Robert; Buerger, Christian; Cobb, Casey

2012-01-01

The frequency and quality of intergroup contact within racially and ethnically diverse schools has potentially important implications for the achievement of desegregation goals. The analyses presented here use survey data to assess intergroup contact within a sample of ten interdistrict magnet schools in Connecticut. Findings indicate frequent…

Intergroup Leadership Across Distinct Subgroups and Identities.

Science.gov (United States)

Rast, David E; Hogg, Michael A; van Knippenberg, Daan

2018-03-01

Resolving intergroup conflict is a significant and often arduous leadership challenge, yet existing theory and research rarely, if ever, discuss or examine this situation. Leaders confront a significant challenge when they provide leadership across deep divisions between distinct subgroups defined by self-contained identities-The challenge is to avoid provoking subgroup identity distinctiveness threat. Drawing on intergroup leadership theory, three studies were conducted to test the core hypothesis that, where identity threat exists, leaders promoting an intergroup relational identity will be better evaluated and are more effective than leaders promoting a collective identity; in the absence of threat, leaders promoting a collective identity will prevail. Studies 1 and 2 ( N = 170; N = 120) supported this general proposition. Study 3 ( N = 136) extended these findings, showing that leaders promoting an intergroup relational identity, but not a collective identity, improved intergroup attitudes when participants experienced an identity distinctiveness threat.

Gender and Intergroup Contact: the Case of Arab Woman

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Mohamed BENITTO

2010-05-01

Full Text Available Coexistence of various ethnic groups within the American and British societies made newspaper headlines following the events of 9/11 in the United States and of July 7 in Great Britain. This article based on survey research and focus group interviews aims to address intergroup contact. In a heterogeneous society, two major tendencies with regard to relation of the Arab community with the mainstream society surface. On the one hand, we notice a tendency to forge a new identity that is deep-rooted in the Arab culture, but with a declared belonging to the host society. On the other hand, there is a tendency of restraint and isolation. This choice of restraint and isolation is sometimes allotted to the ambivalent feelings generated by cultural disparity and stubborn attachment to certain values and traditions. In this context, our study targets the exploration of relationship of Arab women with the mainstream society with the stress laying on the reasons governing ups and downs of their integration within a new cultural environment

Collective Psychological Ownership and Intergroup Relations.

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Verkuyten, Maykel; Martinovic, Borja

2017-11-01

Whereas much social psychological research has studied the in-group and out-group implications of social categorization and collective identity ("we"), little research has examined the nature and relevance of collective psychological ownership ("ours") for intergroup relations. We make a case for considering collective psychological ownership as an important source of intergroup tensions. We do so by integrating theory and research from various social sciences, and we draw out implications for future social psychological research on intergroup relations. We discuss collective psychological ownership in relation to the psychology of possessions, marking behavior, intergroup threats, outgroup exclusion, and in-group responsibility. We suggest that the social psychological processes discussed apply to a range of ownership objects (territory, buildings, cultural artifacts) and various intergroup settings, including international, national, and local contexts, and in organizations and communities. We conclude by providing directions for future research in different intergroup contexts.

Method and Theory of Intergroups in Organizations.

Science.gov (United States)

1980-10-29

Relations and Organizational Diagnosis " (T.R. #3) identified the philosophical formulations of clinical methods for studying organizations, reviewed the...earliest clinical studies of organizations that 4- took a group and intergroup perspective, and critiqued existing approaches to organizational diagnosis . This

Imagining intergroup contact can combat mental health stigma by reducing anxiety, avoidance and negative stereotyping.

Science.gov (United States)

Stathi, Sofia; Tsantila, Katerina; Crisp, Richard J

2012-01-01

Research has demonstrated widespread negative attitudes held toward people with mental health problems. Our study investigated whether a new prejudice reduction technique, imagined intergroup contact (Crisp & Turner, 2009), could combat stigma against people with mental illness, and the mediating processes through which it may exert this beneficial effect. We found that compared to a control condition, participants who imagined a positive encounter with a schizophrenic person reported weakened stereotypes and formed stronger intentions to engage in future social interactions with schizophrenic people in general. Importantly, these intentions were formed due to reduced feelings of anxiety about future interactions. We discuss the implications of these findings for improving the social inclusion of people with mental health problems.

Intergroup Contact: Using Storytelling to Increase Awareness of Lesbian and Gay Older Adults in Long-Term Care Settings.

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Pelts, Michael D; Galambos, Colleen

2017-01-01

Due to societally imposed stigmatization, lesbian and gay (LG) older adults fear and prolong accessing long-term care (LTC) even though they need LTC at higher rates. Interventions that decrease negative attitudes toward LG older adults among LTC staff are a first step in addressing this problem. In this study, the influence of intergroup contact (IGC) on LTC staff members' attitudes toward LG was explored through the use of storytelling as a training mechanism. An embedded mixed-method approach was employed to collect and analyze responses of 60 LTC staff who participated in a storytelling event. Participants completed pretests, posttests, and participated in audio-recorded group discussions. The findings showed that storytelling had a significant (p =0.001) and positive effect (d =0.57) on participants attitudes toward LG. Qualitative analysis revealed 90 codes, 13 process codes, and 4 themes: making meaning of stories, seeking understanding, application to LTC setting, and debating. When guided by IGC theory, storytelling has potential for positively influencing attitudes of LTC staff members toward LG older adults. There is a need for longitudinal work to further test this model.

Intergroup conflict and rational decision making.

Science.gov (United States)

Martínez-Tur, Vicente; Peñarroja, Vicente; Serrano, Miguel A; Hidalgo, Vanesa; Moliner, Carolina; Salvador, Alicia; Alacreu-Crespo, Adrián; Gracia, Esther; Molina, Agustín

2014-01-01

The literature has been relatively silent about post-conflict processes. However, understanding the way humans deal with post-conflict situations is a challenge in our societies. With this in mind, we focus the present study on the rationality of cooperative decision making after an intergroup conflict, i.e., the extent to which groups take advantage of post-conflict situations to obtain benefits from collaborating with the other group involved in the conflict. Based on dual-process theories of thinking and affect heuristic, we propose that intergroup conflict hinders the rationality of cooperative decision making. We also hypothesize that this rationality improves when groups are involved in an in-group deliberative discussion. Results of a laboratory experiment support the idea that intergroup conflict -associated with indicators of the activation of negative feelings (negative affect state and heart rate)- has a negative effect on the aforementioned rationality over time and on both group and individual decision making. Although intergroup conflict leads to sub-optimal decision making, rationality improves when groups and individuals subjected to intergroup conflict make decisions after an in-group deliberative discussion. Additionally, the increased rationality of the group decision making after the deliberative discussion is transferred to subsequent individual decision making.

Intergroup Conflict and Rational Decision Making

Science.gov (United States)

Martínez-Tur, Vicente; Peñarroja, Vicente; Serrano, Miguel A.; Hidalgo, Vanesa; Moliner, Carolina; Salvador, Alicia; Alacreu-Crespo, Adrián; Gracia, Esther; Molina, Agustín

2014-01-01

The literature has been relatively silent about post-conflict processes. However, understanding the way humans deal with post-conflict situations is a challenge in our societies. With this in mind, we focus the present study on the rationality of cooperative decision making after an intergroup conflict, i.e., the extent to which groups take advantage of post-conflict situations to obtain benefits from collaborating with the other group involved in the conflict. Based on dual-process theories of thinking and affect heuristic, we propose that intergroup conflict hinders the rationality of cooperative decision making. We also hypothesize that this rationality improves when groups are involved in an in-group deliberative discussion. Results of a laboratory experiment support the idea that intergroup conflict –associated with indicators of the activation of negative feelings (negative affect state and heart rate)– has a negative effect on the aforementioned rationality over time and on both group and individual decision making. Although intergroup conflict leads to sub-optimal decision making, rationality improves when groups and individuals subjected to intergroup conflict make decisions after an in-group deliberative discussion. Additionally, the increased rationality of the group decision making after the deliberative discussion is transferred to subsequent individual decision making. PMID:25461384

Intergroup conflict and rational decision making.

Directory of Open Access Journals (Sweden)

Vicente Martínez-Tur

Full Text Available The literature has been relatively silent about post-conflict processes. However, understanding the way humans deal with post-conflict situations is a challenge in our societies. With this in mind, we focus the present study on the rationality of cooperative decision making after an intergroup conflict, i.e., the extent to which groups take advantage of post-conflict situations to obtain benefits from collaborating with the other group involved in the conflict. Based on dual-process theories of thinking and affect heuristic, we propose that intergroup conflict hinders the rationality of cooperative decision making. We also hypothesize that this rationality improves when groups are involved in an in-group deliberative discussion. Results of a laboratory experiment support the idea that intergroup conflict -associated with indicators of the activation of negative feelings (negative affect state and heart rate- has a negative effect on the aforementioned rationality over time and on both group and individual decision making. Although intergroup conflict leads to sub-optimal decision making, rationality improves when groups and individuals subjected to intergroup conflict make decisions after an in-group deliberative discussion. Additionally, the increased rationality of the group decision making after the deliberative discussion is transferred to subsequent individual decision making.

Introduction: Negotiation in intergroup conflict

NARCIS (Netherlands)

Demoulin, S.; de Dreu, C.K.W.

2010-01-01

Although conflicts most often occur between groups, research and theory on conflict management and negotiation have largely focused on the interpersonal system and ignored how groups negotiate a solution to their intergroup conflict. Thus we have a thorough understanding of the motivational,

Contact, Perspective Taking, and Anxiety as Predictors of Stereotype Endorsement, Explicit Attitudes, and Implicit Attitudes

OpenAIRE

2007-01-01

Abstract We proposed a model of intergroup contact wherein contact promotes understanding of outgroup perspectives, perspective taking relates to reduced intergroup anxiety that in turn is associated with lessened stereotyping and more positive intergroup attitudes. Additionally, we examined if implicit attitudes followed this model or were directly impacted by contact. White undergraduates (n = 153) completed measures of contact, perspective taking, intergroup anxiety, stereotype ...

Effects of Promotion and Compunction Interventions on Real Intergroup Interactions: Promotion Helps but High Compunction Hurts

OpenAIRE

Greenland, Katy; Xenias, Dimitrios; Maio, Gregory R.

2017-01-01

HIGHLIGHTS  We show the promotion intervention has positive effects during intergroup contact, but that high levels of compunction can have negative effects. Intergroup contact is probably the longest standing and most comprehensively researched intervention to reduce discrimination. It is also part of ordinary social experience, and a key context in which discrimination is played out. In this paper, we explore two additional interventions which are also designed to reduce discriminatio...

A developmental intergroup theory of social stereotypes and prejudice.

Science.gov (United States)

Bigler, Rebecca S; Liben, Lynn S

2006-01-01

Developmental intergroup theory specifies the mechanisms and rules that govern the processes by which children single out groups as targets of stereotyping and prejudice, and by which children learn and construct both the characteristics (i.e., stereotypes) and affective responses (i.e., prejudices) that are associated with these groups in their culture. Specifically, we argue that children have a drive to understand their world, and that this drive is manifested in their tendency to classify natural and non-natural stimuli into categories, and to search the environment for cues about which of the great number of potential bases for categorization are important. The first step in the process of stereotype and prejudice formation is, therefore, the establishment of the psychological salience of some particular set of dimensions. Four factors are hypothesized to affect the establishment of the psychological salience of person attributes: (1) perceptual discriminability of social groups, (2) proportional group size, (3) explicit labeling and use of social groups, and (4) implicit use of social groups. We argue that person characteristics that are perceptually discriminable are more likely than other characteristics to become the basis of stereotyping, but that perceptual discriminability alone is insufficient to trigger psychological salience. Thus, for example, young children's ability to detect race or gender does not mean that these distinctions will inevitably become the bases of stereotypes and prejudice. Instead, for perceptually salient groups to become psychologically salient, one or more additional circumstances must hold, including being characterized by minority status, by adults' use of different labels for different groups, by adults using group divisions functionally, or by segregation. After a particular characteristic that may be used to differentiate among individuals becomes salient, we propose that children who have the ability to sort consistently

Attitudes Towards Seeking Psychological Help: An Integrative Model Based on Contact, Essentialist Beliefs About Mental Illness, and Stigma.

Science.gov (United States)

Hantzi, Alexandra; Anagnostopoulos, Fotios; Alexiou, Eva

2018-06-16

Based on intergroup contact theory, a proposed comprehensive model of attitudes towards seeking professional psychological help was tested, including both potential barriers to mental health help-seeking (i.e., public stigma and self-stigma of seeking help, prejudicial and essentialist beliefs about mental illness, intergroup anxiety) and potential facilitators (i.e., direct and extended contact with persons with mental illness). Relevant measures were completed by 119 community-dwelling participants. Path analysis showed that direct (but not extended) contact with mental illness, by reducing intergroup anxiety, led to less negative beliefs about mental illness and weaker essentialist beliefs about mental illness (the latter being directly and positively associated with negative beliefs about mental illness). Moreover, less negative beliefs about mental illness, by reducing perceptions of self (but not public) stigma of seeking psychological help, were related to more positive attitudes towards help-seeking. Results are discussed in the context of the (unintentional) adverse effects of biogenetic (essentialist) explanations of mental disorders, and the clinical implications regarding interventions that aim at improving help-seeking attitudes.

Bright minds and dark attitudes: lower cognitive ability predicts greater prejudice through right-wing ideology and low intergroup contact.

Science.gov (United States)

Hodson, Gordon; Busseri, Michael A

2012-02-01

Despite their important implications for interpersonal behaviors and relations, cognitive abilities have been largely ignored as explanations of prejudice. We proposed and tested mediation models in which lower cognitive ability predicts greater prejudice, an effect mediated through the endorsement of right-wing ideologies (social conservatism, right-wing authoritarianism) and low levels of contact with out-groups. In an analysis of two large-scale, nationally representative United Kingdom data sets (N = 15,874), we found that lower general intelligence (g) in childhood predicts greater racism in adulthood, and this effect was largely mediated via conservative ideology. A secondary analysis of a U.S. data set confirmed a predictive effect of poor abstract-reasoning skills on antihomosexual prejudice, a relation partially mediated by both authoritarianism and low levels of intergroup contact. All analyses controlled for education and socioeconomic status. Our results suggest that cognitive abilities play a critical, albeit underappreciated, role in prejudice. Consequently, we recommend a heightened focus on cognitive ability in research on prejudice and a better integration of cognitive ability into prejudice models.

Reflexive intergroup bias in third-party punishment.

Science.gov (United States)

Yudkin, Daniel A; Rothmund, Tobias; Twardawski, Mathias; Thalla, Natasha; Van Bavel, Jay J

2016-11-01

Humans show a rare tendency to punish norm-violators who have not harmed them directly-a behavior known as third-party punishment. Research has found that third-party punishment is subject to intergroup bias, whereby people punish members of the out-group more severely than the in-group. Although the prevalence of this behavior is well-documented, the psychological processes underlying it remain largely unexplored. Some work suggests that it stems from people's inherent predisposition to form alliances with in-group members and aggress against out-group members. This implies that people will show reflexive intergroup bias in third-party punishment, favoring in-group over out-group members especially when their capacity for deliberation is impaired. Here we test this hypothesis directly, examining whether intergroup bias in third-party punishment emerges from reflexive, as opposed to deliberative, components of moral cognition. In 3 experiments, utilizing a simulated economic game, we varied participants' group relationship to a transgressor, measured or manipulated the extent to which they relied on reflexive or deliberative judgment, and observed people's punishment decisions. Across group-membership manipulations (American football teams, nationalities, and baseball teams) and 2 assessments of reflexive judgment (response time and cognitive load), reflexive judgment heightened intergroup bias, suggesting that such bias in punishment is inherent to human moral cognition. We discuss the implications of these studies for theories of punishment, cooperation, social behavior, and legal practice. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

On multiscale moving contact line theory.

Science.gov (United States)

Li, Shaofan; Fan, Houfu

2015-07-08

In this paper, a multiscale moving contact line (MMCL) theory is presented and employed to simulate liquid droplet spreading and capillary motion. The proposed MMCL theory combines a coarse-grained adhesive contact model with a fluid interface membrane theory, so that it can couple molecular scale adhesive interaction and surface tension with hydrodynamics of microscale flow. By doing so, the intermolecular force, the van der Waals or double layer force, separates and levitates the liquid droplet from the supporting solid substrate, which avoids the shear stress singularity caused by the no-slip condition in conventional hydrodynamics theory of moving contact line. Thus, the MMCL allows the difference of the surface energies and surface stresses to drive droplet spreading naturally. To validate the proposed MMCL theory, we have employed it to simulate droplet spreading over various elastic substrates. The numerical simulation results obtained by using MMCL are in good agreement with the molecular dynamics results reported in the literature.

Collective narcissism moderates the effect of in-group image threat on intergroup hostility.

Science.gov (United States)

Golec de Zavala, Agnieszka; Cichocka, Aleksandra; Iskra-Golec, Irena

2013-06-01

Results of 4 experiments demonstrated that under in-group image threat collective narcissism predicts retaliatory intergroup hostility. Under in-group criticism (vs. praise) collective narcissists expressed intention to harm the offending out-group but not other, nonoffending out-groups. This effect was specific to collective narcissism and was replicated in studies that accounted for the overlap between collective narcissism and individual narcissism, in-group positivity (in-group identification, blind and constructive patriotism), social dominance orientation, and right wing authoritarianism. The link between collective narcissism and retaliatory intergroup hostility under in-group image threat was found in the context of national identity and international relations and in the context of a social identity defined by university affiliation. Study 4 demonstrated that the relationship between collective narcissism and intergroup hostility was mediated by the perception of in-group criticism as personally threatening. The results advance our understanding of the mechanism driving the link between collective narcissism and intergroup hostility. They indicate that threatened egotism theory can be extended into the intergroup domain. PsycINFO Database Record (c) 2013 APA, all rights reserved.

The anatomy of Intergroups

DEFF Research Database (Denmark)

Nedergaard, Peter; Jensen, Mads Christian Dagnis

2014-01-01

Intergroups are key components in the European Parliament's modus operandi, allowing members from different political groups to focus on specific political topics. Hitherto, the defining characteristics of Intergroups have not received much attention in academic literature. This article remedies ...

Moral Judgments about Jewish-Arab Intergroup Exclusion: The Role of Cultural Identity and Contact

Science.gov (United States)

Brenick, Alaina; Killen, Melanie

2014-01-01

Prejudice and discrimination as justifications for social exclusion are often viewed as violations of the moral principles of welfare, justice, and equality, but intergroup exclusion can also often be viewed as a necessary and legitimate means to maintain group identity and cohesion (Rutland, Killen, & Abrams, 2010). The current study was…

Aversive Racism and Intergroup Contact Theories: Cultural Competence in a Segregated World

Science.gov (United States)

Rodenborg, Nancy A.; Boisen, Laura A.

2013-01-01

The United States remains highly segregated, and social work students are likely to live and work in segregated contexts. What implications does this have for their cultural competence? Does segregation affect social workers' ability to serve diverse clients without bias? This article reviews two social psychology theories, aversive racism…

Intergroup communication between hospital doctors: implications for quality of patient care.

Science.gov (United States)

Hewett, David G; Watson, Bernadette M; Gallois, Cindy; Ward, Michael; Leggett, Barbara A

2009-12-01

Hospitals involve a complex socio-technical health system, where communication failures influence the quality of patient care. Research indicates the importance of social identity and intergroup relationships articulated through power, control, status and competition. This study focused on interspecialty communication among doctors for patients requiring the involvement of multiple specialist departments. The paper reports on an interview study in Australia, framed by social identity and communication accommodation theories of doctors' experiences of managing such patients, to explore the impact of communication. Interviews were undertaken with 45 doctors working in a large metropolitan hospital, and were analysed using Leximancer (text mining software) and interpretation of major themes. Findings indicated that intergroup conflict is a central influence on communication. Contested responsibilities emerged from a model of care driven by single-specialty ownership of the patient, with doctors allowed to evade responsibility for patients over whom they had no sense of ownership. Counter-accommodative communication, particularly involving interpersonal control, appeared as important for reinforcing social identity and winning conflicts. Strategies to resolve intergroup conflict must address structural issues generating an intergroup climate and evoke interpersonal salience to moderate their effect.

Abelian Chern-Simons theory and contact torsion

DEFF Research Database (Denmark)

McLellan, Brendan Donald Kenneth

2013-01-01

Chern-Simons theory on a closed contact three-manifold is studied when the Lie group for gauge transformations is compact, connected and abelian. A shift reduced abelian Chern-Simons partition function is introduced using an alternative formulation of the partition function using formal ideas in ...... in quantum field theory. We compare the shift reduced partition function with other formulations of the abelian Chern-Simons partition function. This study naturally motivates an Atiyah-Patodi-Singer type index problem in contact geometry.......Chern-Simons theory on a closed contact three-manifold is studied when the Lie group for gauge transformations is compact, connected and abelian. A shift reduced abelian Chern-Simons partition function is introduced using an alternative formulation of the partition function using formal ideas...

Intergroup Anxiety: A Person X Situation Approach.

Science.gov (United States)

Britt, Thomas W.; And Others

1996-01-01

Offers a person X situation approach to the study of intergroup anxiety in which anxiety in intergroup encounters is viewed as a transaction between the individual and the environment. An individual difference measure of intergroup anxiety toward African Americans is developed. Presents studies assessing the scale's reliability and validity.…

Ethnolinguistic Vitality and Intergroup Processes

Science.gov (United States)

Ehala, Martin

2010-01-01

The paper argues that ethnolinguistic vitality depends on four crucial social psychological factors: perceived strength differential, intergroup distance, utilitarianism and intergroup discordance. The influence of these factors on the vitality of subordinate and dominant groups is outlined. It is proposed that the vitality of both types of groups…

The Counter-Normative Effects of Service-Learning: Fostering Attitudes toward Social Equality through Contact and Autonomy

Science.gov (United States)

Brown, Margaret A.; Wymer, Jared D.; Cooper, Cierra S.

2016-01-01

Power dynamics are implicated in intergroup prosocial behavior (Nadler & Halabi, 2015). This research investigated two factors that influence the effect of intergroup prosocial behavior on views of social equality: amount of direct intergroup contact and type of helping. Students in a social psychology course (N = 93) were randomly assigned to…

Intergroup Prisoner’s Dilemma with Intragroup Power Dynamics

Directory of Open Access Journals (Sweden)

Christian Lebiere

2011-02-01

Full Text Available The Intergroup Prisoner’s Dilemma with Intragroup Power Dynamics (IPD^2 is a new game paradigm for studying human behavior in conflict situations. IPD^2 adds the concept of intragroup power to an intergroup version of the standard Repeated Prisoner’s Dilemma game. We conducted a laboratory study in which individual human participants played the game against computer strategies of various complexities. The results show that participants tend to cooperate more when they have greater power status within their groups. IPD^2 yields increasing levels of mutual cooperation and decreasing levels of mutual defection, in contrast to a variant of Intergroup Prisoner’s Dilemma without intragroup power dynamics where mutual cooperation and mutual defection are equally likely. We developed a cognitive model of human decision making in this game inspired by the Instance-Based Learning Theory (IBLT and implemented within the ACT-R cognitive architecture. This model was run in place of a human participant using the same paradigm as the human study. The results from the model show a pattern of behavior similar to that of human data. We conclude with a discussion of the ways in which the IPD^2 paradigm can be applied to studying human behavior in conflict situations. In particular, we present the current study as a possible contribution to corroborating the conjecture that democracy reduces the risk of wars.

High outgroup entitativity can inhibit intergroup retribution.

Science.gov (United States)

Newheiser, Anna-Kaisa; Dovidio, John F

2015-06-01

Understanding the psychological processes that are involved in the perpetuation and escalation of intergroup conflict remains an important goal for intergroup relations research. In the present research, we examined perceived outgroup entitativity as a potential determinant of intergroup hostility. In intergroup conflict situations, high-entitative outgroups are perceived as particularly deserving of retribution; however, high-entitative outgroups are also perceived as efficacious and capable of retaliating successfully, suggesting that people may inhibit hostility against high-entitative (vs. low-entitative) outgroups that are in a position to retaliate. We tested this prediction in two studies. In Study 1, we manipulated intergroup provocation and outgroup entitativity, and found that higher negative mood predicted greater aggression against a low-entitative provoker outgroup, but failed to predict aggression against a high-entitative provoker outgroup that was plausibly in a position to retaliate. In Study 2, we held provocation constant while manipulating outgroup entitativity and the possibility of retaliation by the outgroup, and found that people acted in a retributive manner against a high-entitative provoker outgroup only when the outgroup was not in a position to retaliate. Implications for intergroup conflict are discussed. © 2014 The British Psychological Society.

Conservatism, institutionalism, and the social control of intergroup conflict.

Science.gov (United States)

King, Ryan D

2008-03-01

This research investigates the state social control of intergroup conflict by assessing the sociopolitical determinants of hate crime prosecutions. Consistent with insights from the political sociology of punishment, group-threat accounts of intergroup relations and the state, and neoinstitutional theory, the findings suggest that hate crime prosecutions are fewer where political conservatism, Christian fundamentalism, and black population size are higher, although this last effect is nonlinear. Linkages between district attorneys' offices and communities, on the other hand, increase hate crime prosecutions and the likelihood of offices' creating hate crime policies. Yet these policies are sometimes decoupled from actual enforcement, and such decoupling is more likely in politically conservative districts. The results indicate that common correlates of criminal punishment have very different effects on types of state social control that are protective of minority groups, and also suggest conditions under which policy and practice become decoupled in organizational settings.

The evolutionary interplay of intergroup conflict and altruism in humans: a review of parochial altruism theory and prospects for its extension.

Science.gov (United States)

Rusch, Hannes

2014-11-07

Drawing on an idea proposed by Darwin, it has recently been hypothesized that violent intergroup conflict might have played a substantial role in the evolution of human cooperativeness and altruism. The central notion of this argument, dubbed 'parochial altruism', is that the two genetic or cultural traits, aggressiveness against the out-groups and cooperativeness towards the in-group, including self-sacrificial altruistic behaviour, might have coevolved in humans. This review assesses the explanatory power of current theories of 'parochial altruism'. After a brief synopsis of the existing literature, two pitfalls in the interpretation of the most widely used models are discussed: potential direct benefits and high relatedness between group members implicitly induced by assumptions about conflict structure and frequency. Then, a number of simplifying assumptions made in the construction of these models are pointed out which currently limit their explanatory power. Next, relevant empirical evidence from several disciplines which could guide future theoretical extensions is reviewed. Finally, selected alternative accounts of evolutionary links between intergroup conflict and intragroup cooperation are briefly discussed which could be integrated with parochial altruism in the future. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

The evolutionary interplay of intergroup conflict and altruism in humans: a review of parochial altruism theory and prospects for its extension

Science.gov (United States)

Rusch, Hannes

2014-01-01

Drawing on an idea proposed by Darwin, it has recently been hypothesized that violent intergroup conflict might have played a substantial role in the evolution of human cooperativeness and altruism. The central notion of this argument, dubbed ‘parochial altruism’, is that the two genetic or cultural traits, aggressiveness against the out-groups and cooperativeness towards the in-group, including self-sacrificial altruistic behaviour, might have coevolved in humans. This review assesses the explanatory power of current theories of ‘parochial altruism’. After a brief synopsis of the existing literature, two pitfalls in the interpretation of the most widely used models are discussed: potential direct benefits and high relatedness between group members implicitly induced by assumptions about conflict structure and frequency. Then, a number of simplifying assumptions made in the construction of these models are pointed out which currently limit their explanatory power. Next, relevant empirical evidence from several disciplines which could guide future theoretical extensions is reviewed. Finally, selected alternative accounts of evolutionary links between intergroup conflict and intragroup cooperation are briefly discussed which could be integrated with parochial altruism in the future. PMID:25253457

Intergroup Reconciliation between Flemings and Walloons: The Predictive Value of Cognitive Style, Authoritarian Ideology, and Intergroup Emotions

Directory of Open Access Journals (Sweden)

Jasper Van Assche

2017-11-01

Full Text Available Testifying to the gap in fundamental research on positive intergroup outcomes, we investigated reconciliation attitudes in a non-violent intergroup context (i.e., the linguistic conflict in Belgium. By incorporating both important predictors of negative outgroup attitudes (i.e., individual differences in rigid cognitive styles and authoritarian ideologies, and important predictors of reconciliation (i.e., intergroup emotions, we aimed to contribute to a more comprehensive theoretical framework for the analysis of intergroup relations. We recruited one Flemish ('N' = 310 and one Walloon ('N' = 365 undergraduate students sample to test the proposed model. Structural equation analyses with maximum likelihood estimation were conducted using the Lavaan package. In both samples, similar patterns were found. More in particular, the need for cognitive closure appeared to be the basic predictor of right-wing attitudes (i.e., right-wing authoritarianism and social dominance orientation and essentialist thinking, which were then associated with less outgroup empathy and trust, and more outgroup anger. Furthermore, outgroup trust and empathy were positively related to reconciliation. Interestingly, some differences between the Flemish and Walloon sample were found, such as the direct effects of need for closure and social dominance orientation in the first sample, and the non-significant effects of essentialism in the latter sample. Considering the ongoing public and political debate about the linguistic conflict in Belgium, these findings shed a new light on how individual differences relate to specific outgroup emotions, and how these are associated with important intergroup outcomes in the face of intergroup conflict.

The relationship between contact and attitudes: Reducing prejudice toward individuals with intellectual and developmental disabilities.

Science.gov (United States)

Keith, Jessica M; Bennetto, Loisa; Rogge, Ronald D

2015-12-01

Increases in intellectual and developmental disability (IDD) diagnoses coupled with higher rates of inclusion in school and community settings, has created more opportunities for exposure and integration between those with IDD and the mainstream population. Previous research has found that increased contact can lead to more positive attitudes toward those with IDD. The current study further investigated this impact of contact on attitudes by examining the influence of the quality and quantity of contact on both explicit and implicit levels of prejudice, while also considering potential mediation via intergroup anxiety and implicit attitudes. Based on past research and theory, we predicted that contact (especially quality contact) would have a strong relationship with explicit and implicit positive attitudes toward individuals with IDD. In the present study, 550 people completed a survey and short task that measured their level of contact with individuals with IDD across their lifetime, their current attitudes toward these individuals, and other constructs that are thought to influence this relationship. Multiple regression analyses suggested consistent links between higher quality of contact and lower levels of prejudice toward individuals with IDD at both the explicit and implicit levels. After controlling for quality of contact, higher quantity of contact was either not significantly associated with our measures of prejudice or was, importantly, associated with higher levels of prejudice. Additional analyses support intergroup anxiety and implicit positive attitudes as significant mediators in the associations between quality of contact and the various dimensions of explicit prejudice. Thus, it would seem that it is the quality of interpersonal interactions that is most strongly related to positive attitudes toward individuals with IDD, making it crucial to take care when developing inclusion opportunities in community settings. Copyright © 2015 Elsevier Ltd

[The role of collective victimhood in intergroup aggression: Japan-China relations].

Science.gov (United States)

Nawata, Kengo; Yamaguchi, Hiroyuki

2012-12-01

This study examines an effect of collective victimhood in intergroup relations. Collective victimhood is the belief that an ingroup has been harmed by an outgroup. Previous studies focusing on collective victimhood have shown that collective victimhood escalates intergroup conflict. We predicted that the effect of collective victimhood on intergroup aggression would involve two different emotional processes: anger and fear. To test this hypothesis, Japanese attitudes toward the Chinese were examined in the context of Japan-China relations. The results of structural equation modeling showed that collective victimhood enhanced both anger and fear. However, intergroup emotions had converse effects on intergroup aggression. While anger promoted intergroup aggression, fear inhibited it. Nationalism promoted collective victimhood. These findings suggest that, in intergroup conflict, collective victimhood affects intergroup aggression through two emotional processes, which have inverse effects on the aggression.

Parochial cooperation in nested intergroup dilemmas is reduced when it harms out-groups.

Science.gov (United States)

Aaldering, Hillie; Ten Velden, Femke S; van Kleef, Gerben A; De Dreu, Carsten K W

2018-06-01

In intergroup settings, humans often contribute to their in-group at a personal cost. Such parochial cooperation benefits the in-group and creates and fuels intergroup conflict when it simultaneously hurts out-groups. Here, we introduce a new game paradigm in which individuals can display universal cooperation (which benefits both in- and out-group) as well as parochial cooperation that does, versus does not hurt the out-group. Using this set-up, we test hypotheses derived from group selection theory, social identity, and bounded generalized reciprocity theory. Across three experiments we find, first, that individuals choose parochial over universal cooperation. Second, there was no evidence for a motive to maximize differences between in- and out-group, which is central to both group selection and social identity theory. However, fitting bounded generalized reciprocity theory, we find that individuals with a prosocial value orientation display parochial cooperation, provided that this does not harm the out-group; individualists, in contrast, display parochialism whether or not nut it hurts the out-group. Our findings were insensitive to cognitive taxation (Experiments 2-3), and emerged even when universal cooperation served social welfare more than parochialism (Experiment 3). (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Support for Kurdish language rights in Turkey : The roles of ethnic group, group identifications, contact, and intergroup perceptions

NARCIS (Netherlands)

Çelebi, Elif; Verkuyten, Maykel; Smyrnioti, Natasa

2016-01-01

The question of Kurdish language rights has been a central issue in the Turkish–Kurdish conflict. The current study examined endorsement of Kurdish language rights in relation to intergroup factors (i.e. group identifications, cross-group friendships, perceived discrimination, and perceived

Intergroup contact and ingroup reappraisal : examining the deprovincialization thesis

NARCIS (Netherlands)

Verkuyten, M.J.A.M.; Thijs, J.T.; Bekhuis, H.

2010-01-01

According to the deprovincialization thesis, interethnic contact involves a reappraisal and distancing from the ingroup. Contact can broaden one’s horizon by acknowledging and recognizing the value of other cultures and thereby putting the taken-for-granted own cultural standards into perspective.

The communication of "pure" group-based anger reduces tendencies toward intergroup conflict because it increases out-group empathy.

Science.gov (United States)

de Vos, Bart; van Zomeren, Martijn; Gordijn, Ernestine H; Postmes, Tom

2013-08-01

The communication of group-based anger in intergroup conflict is often associated with destructive conflict behavior. However, we show that communicating group-based anger toward the out-group can evoke empathy and thus reduce intergroup conflict. This is because it stresses the value of maintaining a positive long-term intergroup relationship, thereby increasing understanding for the situation (in contrast to the communication of the closely related emotion of contempt). Three experiments demonstrate that the communication of group-based anger indeed reduces destructive conflict intentions compared with (a) a control condition (Experiments 1-2), (b) the communication of group-based contempt (Experiment 2), and (c) the communication of a combination of group-based anger and contempt (Experiments 2-3). Moreover, results from all three experiments reveal that empathy mediated the positive effect of communicating "pure" group-based anger. We discuss the implications of these findings for the theory and practice of communicating emotions in intergroup conflicts.

Intergroup friendships in intractable conflicts : a case study of the Middle East Program for Young Leaders (MEP)

OpenAIRE

Breivik, Norunn

2006-01-01

The contact hypothesis proposes that interaction of different groups reduces intergroup prejudice if certain optimal conditions are present (e.g. Allport, 1958). Critics, though, have pointed to the danger of research built on the contact hypothesis of Gordon Allport being applicable only in rare contexts, under highly idealized conditions (e.g. Dixon et al. 2005: 1). The generalisation of such research may not be useful in specific contexts where these conditions are lacking. When applied to...

Intergroup Contact and Ingroup Reappraisal: Examining the Deprovincialization Thesis

Science.gov (United States)

Verkuyten, Maykel; Thijs, Jochem; Bekhuis, Hidde

2010-01-01

According to the deprovincialization thesis, interethnic contact involves a reappraisal and distancing from the ingroup. Contact can broaden one's horizon by acknowledging and recognizing the value of other cultures and thereby putting the taken-for-granted own cultural standards into perspective. The current research uses data from three surveys…

The Idea Factory: An Interactive Intergroup Exercise

Science.gov (United States)

Rosh, Lisa; Leach, Evan

2011-01-01

This article outlines the Idea Factory exercise, an interactive exercise designed to help participants examine group, individual, and organizational factors that affect intergroup conflict. Specific emphasis is placed on exploring the relationship between intra- and intergroup dynamics and identifying managerial practices that foster effective…

The Process Model of Group-Based Emotion: Integrating Intergroup Emotion and Emotion Regulation Perspectives.

Science.gov (United States)

Goldenberg, Amit; Halperin, Eran; van Zomeren, Martijn; Gross, James J

2016-05-01

Scholars interested in emotion regulation have documented the different goals and strategies individuals have for regulating their emotions. However, little attention has been paid to the regulation of group-based emotions, which are based on individuals' self-categorization as a group member and occur in response to situations perceived as relevant for that group. We propose a model for examining group-based emotion regulation that integrates intergroup emotions theory and the process model of emotion regulation. This synergy expands intergroup emotion theory by facilitating further investigation of different goals (i.e., hedonic or instrumental) and strategies (e.g., situation selection and modification strategies) used to regulate group-based emotions. It also expands emotion regulation research by emphasizing the role of self-categorization (e.g., as an individual or a group member) in the emotional process. Finally, we discuss the promise of this theoretical synergy and suggest several directions for future research on group-based emotion regulation. © 2015 by the Society for Personality and Social Psychology, Inc.

INTERGROUP RELATIONS IN NIGERIA: THE DYNAMICS AND ...

African Journals Online (AJOL)

Prof

production/generation and its associated social relations of production in the country. ... Intergroup relations, as a subject matter, have been subjected under .... Its emergence marked a new line of thought in the field of intergroup relations. The ..... the role of the emergent nationalists like Chief Nnamdi Azikiwe, Alhaji Tafewa.

Mathematical Modeling of Contact Problems of Elasticity Theory with Continuous Unilateral Contact

Directory of Open Access Journals (Sweden)

I. V. Stankevich

2015-01-01

Full Text Available The work [1] presents the formulation and numerical solution of the problem concerning the unilateral discrete contact interaction of an elastic body and a rigid half-space. However, many parts and components of engineering structures have a pronounced continuous contact within a given surface [2, 3]. In this paper we consider a special case of this option of contact interaction when, the elastic body of finite size, subjected to external forces, is based on a rigid half-space. Contact occurs through a dedicated contact surface, which in general can change their sizes.Developed to solve this problem, a numerical algorithm is a further adaptation and development of the approaches described in [1]. The paper shows results of solving the model problem of the elasticity theory with and without taking friction into account. In the latter case, were additionally obtained numerical data characterizing the convergence of the solution.

The operator formalism and contact terms in string theory

International Nuclear Information System (INIS)

Doyle, M.D.

1992-01-01

The operator formalism has proven to be a powerful tool in string theory. In particular, by making explicit the role of a choice of local coordinates (or, equivalently, a normal-ordering prescription) at vertex operator insertions, it provides a framework for understanding the insertion of very general states in both on-shell string theory and string field theory, for formulating a semirigid N = 2 geometry-based approach to topological gravity, for resolving ambiguities in fermionic string theory, and for analyzing contact interactions. The main focus of this thesis on this last application of the operator formalism, although it touches on each of the others. The first goal is the analysis of the dilaton contact terms required for the dilaton equation in the bosonic and heterotic strings. In the bosonic case, a coordinate family appropriate for a punctured sphere is given and is used to calculate dilaton two-point functions. This coordinate family is later generalized to a 'good' coordinate family appropriate for dilaton calculations on higher genus surfaces. It is found that dilaton-dilaton contact terms are improperly normalized resulting in the failure of the dilaton equation, suggesting that the zero-momentum dilaton is not the string coupling constant. This seems to be the result of a tachyon divergence. A similar calculation in the heterotic case, where there is no tachyon, shows that the dilaton contact terms are properly normalized, and that the dilaton equation and the interpretation of the dilaton as the string coupling constant goes through. The other major goal is re-examination of Green and Seiberg's work which showed that, in simple treatments of fermionic string theory, it is necessary to introduce contact interactions when vertex operators collide to avoid the failure of certain superconformal Ward identities

Perspective-Taking Increases Willingness to Engage in Intergroup Contact

OpenAIRE

Wang, Cynthia S.; Kenneth, Tai; Ku, Gillian; Galinsky, Adam D.

2014-01-01

The current research explored whether perspective-taking increases willingness to engage in contact with stereotyped outgroup members. Across three studies, we find that perspective-taking increases willingness to engage in contact with negatively-stereotyped targets. In Study 1, perspective-takers sat closer to, whereas stereotype suppressors sat further from, a hooligan compared to control participants. In Study 2, individual differences in perspective-taking tendencies predicted individual...

Equal but different: Effects of equality/inclusion and cultural pluralism on intergroup outcomes in multiethnic classrooms.

Science.gov (United States)

Schwarzenthal, Miriam; Schachner, Maja K; van de Vijver, Fons J R; Juang, Linda P

2018-04-01

Integrating research on intergroup contact and intercultural relations, we investigated effects of 2 types of cultural diversity norms (equality/inclusion and cultural pluralism) on outgroup orientation and perceived discrimination among students of immigrant and nonimmigrant background. Our sample comprised 1,975 6th graders (M age = 11.53, SD age = 0.69, 47% female) in Germany, of whom 1,213 (61%) were of immigrant background, defined as having at least 1 parent born in a different country. A total of 83 countries of origin were represented. We applied a multilevel framework to assess the impact of individual-level and class-level predictors on intergroup outcomes, controlling for the classroom ethnic composition, school track, and individual-level covariates. Immigrant background was treated as a moderator. The 2 types of cultural diversity norms were generally associated with more positive intergroup outcomes. Some of the associations differed in strength between students of immigrant and nonimmigrant background. There were stronger associations of equality/inclusion with higher outgroup orientation among students of nonimmigrant background and with lower perceived discrimination among students of immigrant background. Ethnic composition, as well as the classroom-aggregated diversity norms (diversity climate) showed weaker relations with the outcome variables. Equality/inclusion norms and cultural pluralism norms can make complementary contributions to positive relations between students of immigrant and nonimmigrant background. Equality/inclusion norms foster positive contact and equal treatment, while cultural pluralism norms emphasize that it is also important to value diversity.¹ (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Social Exclusion in Childhood: A Developmental Intergroup Perspective

Science.gov (United States)

Killen, Melanie; Mulvey, Kelly Lynn; Hitti, Aline

2013-01-01

"Interpersonal" rejection and "intergroup" exclusion in childhood reflect different, but complementary, aspects of child development. Interpersonal rejection focuses on individual differences in personality traits, such as wariness and being fearful, to explain bully-victim relationships. In contrast, intergroup exclusion focuses on how in-group…

Warriors and peacekeepers: Testing a biosocial implicit leadership hypothesis of intergroup relations using masculine and feminine faces

NARCIS (Netherlands)

Spisak, B.R.; Dekker, P.H.; Krüger, M.; van Vugt, M.

2012-01-01

This paper examines the impact of facial cues on leadership emergence. Using evolutionary social psychology, we expand upon implicit and contingent theories of leadership and propose that different types of intergroup relations elicit different implicit cognitive leadership prototypes. It is argued

The steady-state tangential contact problem for a falling drop type of contact area on corrugated rail by simplified theory of rolling contact

Science.gov (United States)

Piotrowski, Jerzy

1991-10-01

Investigation of contact mechanical nonlinearities of a mathematical model of corrugation revealed that the typical shape of contact patch resembles a falling drop of water. A contact patch of that shape was approximated with a figure composed of two parts of ellipses with different eccentricities. The contact pressure distribution was assumed as a smoothing ensemble of two paraboloidal distributions. The description of a general case of double half elliptical contact area was given but a special case of double half elliptical contact is more interesting as it possesses some Hertzian properties. It was shown how three geometrical parameters of double half elliptical contact can be chosen when actual, non-Hertzian contact is known. A linear theory was written which indicates that the lateral vibrations of the rail may be excited only due to shape variation on corrugation even if any other cause for these vibrations does not exist. For nonlinear theory a computer program, based on FASTSIM algorithm by Kalker, was written. The aim is to calculate the creep forces and frictional power density distribution over the contact area. Also, a graphic program visualizing the solution was written. Numerical results are not provided; unattended and unsolved problems relevant for this type of contact are listed.

Differing Levels of Gender Salience in Preschool Classrooms: Effects on Children's Gender Attitudes and Intergroup Bias

Science.gov (United States)

Hilliard, Lacey J.; Liben, Lynn S.

2010-01-01

Developmental intergroup theory posits that when environments make social-group membership salient, children will be particularly likely to apply categorization processes to social groups, thereby increasing stereotypes and prejudices. To test the predicted impact of environmental gender salience, 3- to 5-year-old children (N = 57) completed…

Social Norms and Self-Presentation: Children's Implicit and Explicit Intergroup Attitudes

Science.gov (United States)

Rutland, Adam; Cameron, Lindsey; Milne, Alan; McGeorge, Peter

2005-01-01

Two studies examined whether social norms and children's concern for self-presentation affect their intergroup attitudes. Study 1 examined racial intergroup attitudes and normative beliefs among children aged 6 to 16 years (n=155). Accountability (i.e., public self-focus) was experimentally manipulated, and intergroup attitudes were assessed using…

Intergroup differentiation in computer-mediated communication : Effects of depersonalization

NARCIS (Netherlands)

Postmes, T; Spears, R; Lea, M

Two studies examined intergroup discussions via computer-mediated communication systems. It was hypothesized that depersonalization, in comparison with individuated interaction, would increase the tendency for intergroup differentiation in attitudes and stereotypes, In Study 1, 24 groups

Collective self and individual choice : The effects of inter-group comparative context on environmental values and behaviour

NARCIS (Netherlands)

Rabinovich, Anna; Morton, Thomas A.; Postmes, Tom; Verplanken, Bas

2012-01-01

Self-categorization theory suggests that inter-group comparisons inform individual behaviour by affecting perceived in-group stereotypes that are internalized by group members. The present paper provides evidence for this chain of effects in the domain of environmental behaviour. In two studies,

The complement of research and theory in practice: contact theory at work in nonfamilial intergenerational programs.

Science.gov (United States)

Jarrott, Shannon E; Smith, Cynthia L

2011-02-01

We assessed whether a shared site intergenerational care program informed by contact theory contributed to more desirable social behaviors of elders and children during intergenerational programming than a center with a more traditional programming approach that lacks some or all of the contact theory tenets. We observed 59 elder and child participants from the two sites during intergenerational activities. Using the Intergenerational Observation Scale, we coded participants' predominant behavior in 15-s intervals through each activity's duration. We then calculated for each individual the percentage of time frames each behavior code was predominant. Participants at the theory-based program demonstrated higher rates of intergenerational interaction, higher rates of solitary behavior, and lower rates of watching than at the traditional program. Contact theory tenets were optimized when coupled with evidence-based practices. Intergenerational programs with stakeholder support that promotes equal group status, cooperation toward a common goal, and mechanisms of friendship among participants can achieve important objectives for elder and child participants in care settings.

Cultural Values in Intergroup and Single-Group Social Dilemmas.

Science.gov (United States)

Probst; Carnevale; Triandis

1999-03-01

Do cultural values influence the manner in which people cooperate with one another? This study assessed cultural characteristics of individuals and then related these characteristics to cooperative behavior in social dilemmas. Participants were assessed for their degree of vertical and horizontal individualism and collectivism, cultural values identified by Triandis (1995). They made choices in either a single-group or an intergroup social dilemma. The single-group dilemma entailed a three-person dilemma; the intergroup dilemma was identical but added subgroup competition, i.e., an opposing three-person group. The results indicated an interaction between cultural characteristics and type of dilemma for cooperation. The single-group versus intergroup effect reported by Bornstein and Ben-Yossef (1994) was replicated, but only for vertical individualists. The vertical individualists were least cooperative in the single-group dilemma but were more cooperative in the intergroup dilemma-where cooperation with the group maximized personal outcomes. The vertical collectivists were most cooperative in the single-group dilemma but were less cooperative in the intergroup dilemma- where group defection resulted in maximum group outcomes. The horizontal individualists and collectivists exhibited an intermediate level of cooperation, with no differences in cooperation between the single-group and intergroup dilemmas. Taken together, the results suggest that the relationship between cultural values and cooperation, in particular with reference to vertical and horizontal components of individualism and collectivism, is more complex than has been suggested in past research. Copyright 1999 Academic Press.

Mathematical Modeling of Contact Problems of Elasticity Theory with Unilateral Discrete Contact

Directory of Open Access Journals (Sweden)

I. V. Stankevich

2015-01-01

Full Text Available Development and operation of modern machinery and latest technology require reliable estimates of the strength characteristics of the critical elements of structures and technological equipment under the impact of high-intensity thermomechanical loading, accompanied, as a rule, by complex contact interaction. Mathematical modeling of stress-strain state of such parts and components in the contact area, based on adequate mathematical models, modern numerical methods and efficient algorithms that implement the direct determination of displacement fields, strains and stresses, is the main tool that allows fast acquisition of data required for the calculations of strength and durability. The paper considers an algorithm for constructing the numerical solution of the contact problem of elasticity theory in relation to the body, which has an obvious one-sided discrete contact interaction with an elastic half-space. The proposed algorithm is specially designed to have a correction of the tangential forces at discrete contact points, allowing us to achieve sufficiently accurate implementation of the adopted law of friction. The algorithm is embedded in a general finite element technology, with which the application code is generated. Numerical study of discrete unilateral contact interaction of an elastic plate and a rigid half-space showed a high efficiency of the developed algorithm and the application code that implements it.

Intergroup Differences and Their Impact on African American Teachers.

Science.gov (United States)

Mabokela, Reitumetse Obakeng; Madsen, Jean A.

2003-01-01

Examined how intergroup differences within suburban schools affected African American teachers' experiences. Organizational culture strongly influenced how whites treated their minority counterparts. Because the majority established norms, minorities were expected to comply with uniform sets of rules and regulations. Intergroup conflict arose…

Learning to Manage Intergroup Dynamics in Changing Task Environments: An Experiential Exercise

Science.gov (United States)

Hunsaker, Phillip L.

2004-01-01

This article describes an exercise that allows participants to experience the challenges of managing intergroup behavior as an organization's task environment grows and becomes more complex. The article begins with a brief review of models and concepts relating to intergroup dynamics, intergroup conflict, and interventions for effectively managing…

Using Intergroup Dialogue to Promote Social Justice and Change

Science.gov (United States)

Dessel, Adrienne; Rogge, Mary E.; Garlington, Sarah B.

2006-01-01

Intergroup dialogue is a public process designed to involve individuals and groups in an exploration of societal issues such as politics, racism, religion, and culture that are often flashpoints for polarization and social conflict. This article examines intergroup dialogue as a bridging mechanism through which social workers in clinical, other…

Rough viscoelastic sliding contact: Theory and experiments

Science.gov (United States)

Carbone, G.; Putignano, C.

2014-03-01

In this paper, we show how the numerical theory introduced by the authors [Carbone and Putignano, J. Mech. Phys. Solids 61, 1822 (2013), 10.1016/j.jmps.2013.03.005] can be effectively employed to study the contact between viscoelastic rough solids. The huge numerical complexity is successfully faced up by employing the adaptive nonuniform mesh developed by the authors in Putignano et al. [J. Mech. Phys. Solids 60, 973 (2012), 10.1016/j.jmps.2012.01.006]. Results mark the importance of accounting for viscoelastic effects to correctly simulate the sliding rough contact. In detail, attention is, first, paid to evaluate the viscoelastic dissipation, i.e., the viscoelastic friction. Fixed the sliding speed and the normal load, friction is completely determined. Furthermore, since the methodology employed in the work allows to study contact between real materials, a comparison between experimental outcomes and numerical prediction in terms of viscoelastic friction is shown. The good agreement seems to validate—at least partially—the presented methodology. Finally, it is shown that viscoelasticity entails not only the dissipative effects previously outlined, but is also strictly related to the anisotropy of the contact solution. Indeed, a marked anisotropy is present in the contact region, which results stretched in the direction perpendicular to the sliding speed. In the paper, the anisotropy of the deformed surface and of the contact area is investigated and quantified.

Intergroup relations in Nigeria: The dynamics and complexities | Ofili ...

African Journals Online (AJOL)

It is observed that intergroup conflict is caused by an incompatibility of goals regarding material resources. It is the struggle over such material resources as land, oil, gold, and labour that is the source of intergroup conflict in the country and not ethnicity nor prejudiced personality. This explains the checkered history of ...

Tourist typology in social contact: An addition to existing theories

OpenAIRE

Fan, Daisy X.F.; Zhang, H.Q.; Jenkins, C.L.; Tavitiyaman, P.

2017-01-01

Tourist-host social contact, as a unique type of social contact, is not getting sufficient attention in tourism academia considering its remarkable impacts on tourists’ travel attitudes, behaviors and long-term perceptions. The objectives of the current study are to explore the dimensions of tourist-host social contact and to contribute to the theory of tourist typology according to their dynamic nature in tourist-host social interaction. Forty-five in-depth interviews were conducted to gener...

Emotion and aggressive intergroup cognitions: The ANCODI hypothesis.

Science.gov (United States)

Matsumoto, David; Hwang, Hyisung C; Frank, Mark G

2017-01-01

Previous research has suggested an important role for the emotion of hatred in intergroup aggression. Recent theoretical and empirical work has strongly suggested that the combination of anger, contempt, and disgust (ANCODI) comprise the basic elements of hatred, and are the key emotions associated with intergroup aggression. No study, however, has provided evidence that these emotions cause hostile cognitions about specific groups. We report two studies that provide initial evidence. In both, participants were members of ideologically motivated groups and were primed with ANCODI. In Study 1 participants primed with ANCODI produced more aggressive cognitions relative to their opponent outgroup than a neutral outgroup; this effect did not occur for participants primed with fear-sadness. In Study 2 participants primed with ANCODI engaged in more competitive decision making against their opponent outgroups than a neutral outgroup; this effect did not occur for participants primed with disgust only. These findings contribute to the literature on the role of emotion in intergroup aggression and hostility, and provide a more nuanced view of the role of emotions in intergroup relations, possibly identifying the basic emotional elements of hatred. Aggr. Behav. 43:93-107, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Positive expectations encourage generalization from a positive intergroup interaction to outgroup attitudes.

Science.gov (United States)

Deegan, Matthew P; Hehman, Eric; Gaertner, Samuel L; Dovidio, John F

2015-01-01

The current research reveals that while positive expectations about an anticipated intergroup interaction encourage generalization of positive contact to outgroup attitudes, negative expectations restrict the effects of contact on outgroup attitudes. In Study 1, when Blacks and Whites interacted with positive expectations, interaction quality predicted outgroup attitudes to a greater degree than when groups interacted with negative expectations. When expectations (Studies 2 and 3) and the actual interaction quality (Study 4) were manipulated orthogonally, negative expectations about the interaction predicted negative outgroup attitudes, regardless of actual interaction quality. By contrast, participants holding positive expectations who experienced a positive interaction expressed positive outgroup attitudes, whereas when they experienced a negative interaction, they expressed outgroup attitudes as negative as those with negative expectations. Across all four studies, positive expectations encouraged developing outgroup attitudes consistent with interaction quality. © 2014 by the Society for Personality and Social Psychology, Inc.

Nouns cut slices: Effects of linguistic forms on intergroup bias

Czech Academy of Sciences Publication Activity Database

Graf, Sylvie; Bilewicz, M.; Finell, E.; Geschke, D.

2013-01-01

Roč. 32, č. 1 (2013), s. 46-61 ISSN 0261-927X R&D Projects: GA ČR GA13-25656S Institutional support: RVO:68081740 Keywords : nouns * adjectives * intergroup bias * intergroup attitudes Subject RIV: AN - Psychology Impact factor: 0.872, year: 2013

Self esteem and outgroup derogation: A clarification of competing theories

OpenAIRE

Davidowitz, Cara; Childs, Jessica

2008-01-01

Research surrounding the Self Esteem Hypothesis has produced conflicting results and unresolved issues. Whilst the original hypothesis posited that it is individuals low in self-esteem that are motivated to show intergroup discrimination, subsequent research has found evidence to suggest a pattern of individuals high in self esteem showing greater amounts of intergroup discrimination. Furthermore, the Social Identity Theory suggests that this intergroup discrimination will occur between membe...

Inter-group and intra-group assertiveness: adolescents' social skills following cultural transition.

Science.gov (United States)

Korem, Anat; Horenczyk, Gabriel; Tatar, Moshe

2012-08-01

The goals of this study were to examine intra-group and inter-group assertiveness among adolescents, and to compare these two domains of assertiveness between cultural groups in Israel. Measures of intra-group and inter-group assertiveness were developed, and questionnaires were administrated to 441 immigrants from the Former Soviet Union (FSU), 242 immigrants from Ethiopia and 333 non-immigrants. Compared to non-immigrants, FSU and Ethiopian immigrants' inter-group assertiveness was lower. Girls reported higher levels of inter-group assertiveness than boys. Each of the immigrant groups rates itself as equally assertive as the non-immigrant group and more assertive than the other immigrant group. Also, a difference between inter-group and intra-group assertiveness was found among the FSU immigrants. It is argued that adolescents' assertiveness following cultural transition is associated with socio-cultural context, and the implications of this conclusion are discussed. Copyright © 2011 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Warriors and Peacekeepers: Testing a Biosocial Implicit Leadership Hypothesis of Intergroup Relations Using Masculine and Feminine Faces

Science.gov (United States)

Spisak, Brian R.; Dekker, Peter H.; Krüger, Max; van Vugt, Mark

2012-01-01

This paper examines the impact of facial cues on leadership emergence. Using evolutionary social psychology, we expand upon implicit and contingent theories of leadership and propose that different types of intergroup relations elicit different implicit cognitive leadership prototypes. It is argued that a biologically based hormonal connection between behavior and corresponding facial characteristics interacts with evolutionarily consistent social dynamics to influence leadership emergence. We predict that masculine-looking leaders are selected during intergroup conflict (war) and feminine-looking leaders during intergroup cooperation (peace). Across two experiments we show that a general categorization of leader versus nonleader is an initial implicit requirement for emergence, and at a context-specific level facial cues of masculinity and femininity contingently affect war versus peace leadership emergence in the predicted direction. In addition, we replicate our findings in Experiment 1 across culture using Western and East Asian samples. In Experiment 2, we also show that masculine-feminine facial cues are better predictors of leadership than male-female cues. Collectively, our results indicate a multi-level classification of context-specific leadership based on visual cues imbedded in the human face and challenge traditional distinctions of male and female leadership. PMID:22276190

Warriors and peacekeepers: testing a biosocial implicit leadership hypothesis of intergroup relations using masculine and feminine faces.

Science.gov (United States)

Spisak, Brian R; Dekker, Peter H; Krüger, Max; van Vugt, Mark

2012-01-01

This paper examines the impact of facial cues on leadership emergence. Using evolutionary social psychology, we expand upon implicit and contingent theories of leadership and propose that different types of intergroup relations elicit different implicit cognitive leadership prototypes. It is argued that a biologically based hormonal connection between behavior and corresponding facial characteristics interacts with evolutionarily consistent social dynamics to influence leadership emergence. We predict that masculine-looking leaders are selected during intergroup conflict (war) and feminine-looking leaders during intergroup cooperation (peace). Across two experiments we show that a general categorization of leader versus nonleader is an initial implicit requirement for emergence, and at a context-specific level facial cues of masculinity and femininity contingently affect war versus peace leadership emergence in the predicted direction. In addition, we replicate our findings in Experiment 1 across culture using Western and East Asian samples. In Experiment 2, we also show that masculine-feminine facial cues are better predictors of leadership than male-female cues. Collectively, our results indicate a multi-level classification of context-specific leadership based on visual cues imbedded in the human face and challenge traditional distinctions of male and female leadership.

Warriors and peacekeepers: testing a biosocial implicit leadership hypothesis of intergroup relations using masculine and feminine faces.

Directory of Open Access Journals (Sweden)

Brian R Spisak

Full Text Available This paper examines the impact of facial cues on leadership emergence. Using evolutionary social psychology, we expand upon implicit and contingent theories of leadership and propose that different types of intergroup relations elicit different implicit cognitive leadership prototypes. It is argued that a biologically based hormonal connection between behavior and corresponding facial characteristics interacts with evolutionarily consistent social dynamics to influence leadership emergence. We predict that masculine-looking leaders are selected during intergroup conflict (war and feminine-looking leaders during intergroup cooperation (peace. Across two experiments we show that a general categorization of leader versus nonleader is an initial implicit requirement for emergence, and at a context-specific level facial cues of masculinity and femininity contingently affect war versus peace leadership emergence in the predicted direction. In addition, we replicate our findings in Experiment 1 across culture using Western and East Asian samples. In Experiment 2, we also show that masculine-feminine facial cues are better predictors of leadership than male-female cues. Collectively, our results indicate a multi-level classification of context-specific leadership based on visual cues imbedded in the human face and challenge traditional distinctions of male and female leadership.

Differing levels of gender salience in preschool classrooms: effects on children's gender attitudes and intergroup bias.

Science.gov (United States)

Hilliard, Lacey J; Liben, Lynn S

2010-01-01

Developmental intergroup theory posits that when environments make social-group membership salient, children will be particularly likely to apply categorization processes to social groups, thereby increasing stereotypes and prejudices. To test the predicted impact of environmental gender salience, 3- to 5-year-old children (N = 57) completed gender attitude, intergroup bias, and personal preference measures at the beginning and end of a 2-week period during which teachers either did or did not make gender salient. Observations of peer play were also made at both times. After 2 weeks, children in the high- (but not low-) salience condition showed significantly increased gender stereotypes, less positive ratings of other-sex peers, and decreased play with other-sex peers. Children's own activity and occupational preferences, however, remained unaffected. © 2010 The Authors. Child Development © 2010 Society for Research in Child Development, Inc.

Multicultural Contacts in Education: A Case Study of an Exchange Project between Different Ethnic Groups

Science.gov (United States)

Schuitema, Jaap; Veugelers, Wiel

2011-01-01

One important aim of citizenship education is learning to deal with cultural diversity. To this end, schools organise exchange projects to bring students into contact with different social and cultural groups. The aim of this study is to investigate the effects of intergroup contact in educational settings and to understand what the most…

Asymmetric intergroup bullying: The enactment and maintenance of societal inequality at work.

Science.gov (United States)

Soylu, Soydan; Sheehy-Skeffington, Jennifer

2015-07-01

What does inequality mean for dysfunctional organizational behaviours, such as workplace bullying? This article argues that workplace bullying can be understood as a manifestation of intergroup dynamics originating beyond the organization. We introduce the construct of asymmetric intergroup bullying: the disproportionate mistreatment of members of low status groups, with the intended effect of enhancing the subordination of that group in society at large. Analysis of data from 38 interviews with public and private sector workers in Turkey depicts a pattern of asymmetric intergroup bullying, undertaken to achieve organizational and broader sociopolitical goals. Respondents reported bullying acts used to get rid of unwanted personnel, with the goal of avoiding severance pay, or of removing supporters of the former government from positions of political and economic influence. Bullying was also described as working towards the dominance of the sociocultural worldview of one political group over another. We discuss asymmetric intergroup bullying as one mechanism through which acute intergroup hierarchy in the broader society corrupts management practice and employee interactions, in turn exacerbating economic inequality along group lines.

Asymmetric intergroup bullying: The enactment and maintenance of societal inequality at work

Science.gov (United States)

Soylu, Soydan; Sheehy-Skeffington, Jennifer

2015-01-01

What does inequality mean for dysfunctional organizational behaviours, such as workplace bullying? This article argues that workplace bullying can be understood as a manifestation of intergroup dynamics originating beyond the organization. We introduce the construct of asymmetric intergroup bullying: the disproportionate mistreatment of members of low status groups, with the intended effect of enhancing the subordination of that group in society at large. Analysis of data from 38 interviews with public and private sector workers in Turkey depicts a pattern of asymmetric intergroup bullying, undertaken to achieve organizational and broader sociopolitical goals. Respondents reported bullying acts used to get rid of unwanted personnel, with the goal of avoiding severance pay, or of removing supporters of the former government from positions of political and economic influence. Bullying was also described as working towards the dominance of the sociocultural worldview of one political group over another. We discuss asymmetric intergroup bullying as one mechanism through which acute intergroup hierarchy in the broader society corrupts management practice and employee interactions, in turn exacerbating economic inequality along group lines. PMID:26819482

Communicating anger and contempt in intergroup conflict : Exploring their relational functions

NARCIS (Netherlands)

de Vos, Bartholomeus

2015-01-01

Although the experience of anger in intergroup conflict is typically viewed as a destructive force that is best kept under wraps, the current dissertation suggests that its communication can help de-escalate intergroup conflict because of its relational function. Specifically, this entails that the

Accountability Accentuates Interindividual-Intergroup Discontinuity by Enforcing Parochialism.

Science.gov (United States)

Wildschut, Tim; van Horen, Femke; Hart, Claire

2015-01-01

Interindividual-intergroup discontinuity is the tendency for relations between groups to be more competitive than relations between individuals. We examined whether the discontinuity effect arises in part because group members experience normative pressure to favor the ingroup (parochialism). Building on the notion that accountability enhances normative pressure, we hypothesized that the discontinuity effect would be larger when accountability is present (compared to absent). A prisoner's dilemma game experiment supported this prediction. Specifically, intergroup (compared to interindividual) interaction activated an injunctive ingroup-favoring norm, and accountability enhanced the influence of this norm on competitive behavior.

An analysis of intergroup rivalry using Ising model and reinforcement learning

Science.gov (United States)

Zhao, Feng-Fei; Qin, Zheng; Shao, Zhuo

2014-01-01

Modeling of intergroup rivalry can help us better understand economic competitions, political elections and other similar activities. The result of intergroup rivalry depends on the co-evolution of individual behavior within one group and the impact from the rival group. In this paper, we model the rivalry behavior using Ising model. Different from other simulation studies using Ising model, the evolution rules of each individual in our model are not static, but have the ability to learn from historical experience using reinforcement learning technique, which makes the simulation more close to real human behavior. We studied the phase transition in intergroup rivalry and focused on the impact of the degree of social freedom, the personality of group members and the social experience of individuals. The results of computer simulation show that a society with a low degree of social freedom and highly educated, experienced individuals is more likely to be one-sided in intergroup rivalry.

The roles of ingroup identification and outgroup entitativity in intergroup retribution.

Science.gov (United States)

Stenstrom, Douglas M; Lickel, Brian; Denson, Thomas F; Miller, Norman

2008-11-01

A new aspect of intergroup conflict was investigated- vicarious retribution-in which neither the agent of retribution nor the target of retribution are directly involved in the initial intergroup provocation. The underlying processes involved in vicarious intergroup retribution were tested correlationally (Study 1) and experimentally (Study 2). Both ingroup identification and outgroup entitativity predict the degree of vicarious retribution. In both studies, there was evidence of motivated cognition, specifically that highly identified individuals perceived the outgroup as higher in entitativity than individuals low in identification. Structural equation modeling demonstrated that part of the effect of identification on retribution against the outgroup was mediated through perceptions of entitativity.

Aspect of Intergroup Relations in 21st Century Nigeria: Emblem of ...

African Journals Online (AJOL)

This paper is on the aspects of intergroup relations in 21st century Nigeria: Emblem of Ethnicity, Religious Fundamentalism and National Security Crisis, 2000-2014. The objective of the paper is to contribute to some existing literature on the state of intergroup relations in Nigeria. Besides, it would provoke further ...

Culture and contact in the promotion and reduction of anti-gay prejudice: evidence from Jamaica and Britain.

Science.gov (United States)

West, Keon; Hewstone, Miles

2012-01-01

Jamaica has been called "the most homophobic place on Earth" ( Padgett, 2006 , p. 1), and has been involved in numerous international incidents with Britain, and other countries, concerning anti-gay prejudice. However, neither the severity of Jamaican anti-gay prejudice, nor any means of reducing this prejudice has ever been empirically investigated. Intergroup contact-social interaction with a person from another group-is one of the most successful and widely used social-psychological interventions to reduce prejudice and improve intergroup relations. In this article, we compared sexual prejudice in Jamaica to that in Britain and investigated the relationship between contact and sexual prejudice in both countries. Jamaican participants reported more negative attitudes toward gay men than did British participants, but contact was more strongly associated with reduced sexual prejudice for Jamaican participants than for British participants. Implications for reducing Jamaican sexual prejudice are discussed.

The intergroup protocols: Scalable group communication for the internet

Energy Technology Data Exchange (ETDEWEB)

Berket, Karlo [Univ. of California, Santa Barbara, CA (United States)

2000-12-04

Reliable group ordered delivery of multicast messages in a distributed system is a useful service that simplifies the programming of distributed applications. Such a service helps to maintain the consistency of replicated information and to coordinate the activities of the various processes. With the increasing popularity of the Internet, there is an increasing interest in scaling the protocols that provide this service to the environment of the Internet. The InterGroup protocol suite, described in this dissertation, provides such a service, and is intended for the environment of the Internet with scalability to large numbers of nodes and high latency links. The InterGroup protocols approach the scalability problem from various directions. They redefine the meaning of group membership, allow voluntary membership changes, add a receiver-oriented selection of delivery guarantees that permits heterogeneity of the receiver set, and provide a scalable reliability service. The InterGroup system comprises several components, executing at various sites within the system. Each component provides part of the services necessary to implement a group communication system for the wide-area. The components can be categorized as: (1) control hierarchy, (2) reliable multicast, (3) message distribution and delivery, and (4) process group membership. We have implemented a prototype of the InterGroup protocols in Java, and have tested the system performance in both local-area and wide-area networks.

Accountability Accentuates Interindividual—Intergroup Discontinuity by Enforcing Parochialism

Directory of Open Access Journals (Sweden)

Tim eWildschut

2015-11-01

Full Text Available Interindividual-intergroup discontinuity is the tendency for relations between groups to be more competitive than relations between individuals. We examined whether the discontinuity effect arises in part because group members experience normative pressure to favor the ingroup (parochialism. Building on the notion that accountability enhances normative pressure, we hypothesized that the discontinuity effect would be larger when accountability is present (compared to absent. A prisoner’s dilemma game experiment supported this prediction. Specifically, intergroup (compared to interindividual interaction activated an injunctive ingroup-favoring norm, and accountability enhanced the influence of this norm on competitive behavior.

The impact of contact on students' attitudes towards peers with disabilities.

Science.gov (United States)

Schwab, Susanne

2017-03-01

This study aimed to understand the relationship between contact with peers with Special Educational Needs (SEN) and students' attitudes towards their peers with SEN, by examining the inter-group contact theory in regular and inclusive classes. A total of 463 students in 8th grade, with a mean age of 14.42 years, from 25 secondary school classes in Styria (Austria) completed a self-report questionnaire regarding their contact with peers with SEN and their attitudes towards peers with disabilities. Contact was indicated by nominations for joint activities and examined in inclusive and regular classes. The German short version of the Chedoke-McMaster Attitudes towards Children with Handicaps scale (CATCH; Schwab, 2015b; Rosenbaum et al., 1986) was used to measure students' attitudes towards peers with learning disabilities and emotional disorders. Students with SEN are less frequently nominated by their peers for joint activities, such as working together on a school project. Students from inclusive and regular classes did not differ in their attitudes towards peers with SEN. However, those students who nominated at least one peer with SEN for a joint activity had more positive attitudes towards peers with disabilities. Freely choosing contact with a peer with SEN was associated with more positive attitudes towards disability while simply attending the same class may have no effect or even a negative impact on students' attitudes. Copyright © 2017 Elsevier Ltd. All rights reserved.

A two-dimensional model of intergroup leadership: the case of national diversity.

Science.gov (United States)

Pittinsky, Todd L

2010-04-01

The model presented argues that leadership involves bringing together not only diverse individuals but also the subgroups to which they belong. The model further argues that this does not require replacing people's subgroup identities with a superordinate group identity (turning "us" and "them" into "we"); bringing together diverse individuals and their subgroups can be accomplished by promoting positive relations among subgroups, even as their distinctive identities (their senses of "us" and "them") remain. The model conceptualizes positive and negative intergroup attitudes as two independent dimensions of intergroup relations, each with distinct antecedents and distinct associated outcomes. Leaders seeking to create a collective from diverse subgroups must therefore (a) reduce negative intergroup attitudes and (b) increase positive intergroup attitudes. The author applies the model to organizational contexts of national diversity, but it can be applied to leadership across other forms of diversity. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Intergroup contact and religiosity as predictor of between group attitudes in conflict environment

Directory of Open Access Journals (Sweden)

Lalić Bojan R.

2013-01-01

Full Text Available The aim of this research was to identify relations between level of religiosity and level of contact on one side and social attitudes towards members of religious out-groups in conflict environment on the other side. This research was conducted on the sample of Christian Orthodox students in Kosovska Mitrovica (which is partially conflict environment and the Muslims were the out-group towards whom attitudes were analyzed. Attitudes measures we used were social distance scale and semantic differential. Likert type scale was used for religiosity measure, quantity and quality of contact. Controlled variables in this research were: gender, age and social status. Results showed that significant amount of variance was explained by independent variables (R2=.270, F(7,779=9.241, p=.000 for semantic differential and R2=.306, F(5,105=9.241, p=.000. However, there is no significant correlation between religiosity and attitude level towards Muslims. Most of the variance for semantic differential was explained by quality of contact (R2=.255, F(1,109=37,285, p=.000 and this was the only significant predictor for this attitude measure. Quantity of contact was significant predictor for social distance attitude measure, with highest incremental value - calculated by hierarchical linear regression (R2change=.216, F(l,109=30,076, p=.000. Following predictor was quality of contact (R2????????=.049, F(l,108=7,269, p=.008 and the last predictor was sex, with the lowest incremental value (R2=.034, F(1,107=5,159, p=.025. These results are interpreted by probable existence of several types of religiosity. There is possibility that general religiosity we measured in this research, was influenced by different types of religiosity, which could be the reason why correlation was not identified. Correlation between quality of contact confirms results published by other authors (Allport, Pettigrew who claimed that contact by itself cannot diminish prejudices and lead to change

Computational models of intergroup competition and warfare.

Energy Technology Data Exchange (ETDEWEB)

Letendre, Kenneth (University of New Mexico); Abbott, Robert G.

2011-11-01

This document reports on the research of Kenneth Letendre, the recipient of a Sandia Graduate Research Fellowship at the University of New Mexico. Warfare is an extreme form of intergroup competition in which individuals make extreme sacrifices for the benefit of their nation or other group to which they belong. Among animals, limited, non-lethal competition is the norm. It is not fully understood what factors lead to warfare. We studied the global variation in the frequency of civil conflict among countries of the world, and its positive association with variation in the intensity of infectious disease. We demonstrated that the burden of human infectious disease importantly predicts the frequency of civil conflict and tested a causal model for this association based on the parasite-stress theory of sociality. We also investigated the organization of social foraging by colonies of harvester ants in the genus Pogonomyrmex, using both field studies and computer models.

Collective Psychological Ownership and Intergroup Relations

NARCIS (Netherlands)

Verkuyten, Maykel; Martinovic, Borja

2017-01-01

Whereas much social psychological research has studied the in-group and out-group implications of social categorization and collective identity (“we”), little research has examined the nature and relevance of collective psychological ownership (“ours”) for intergroup relations. We make a case for

From outgroups to allied forces: Effect of intergroup cooperation in violent and nonviolent video games on boosting favorable outgroup attitudes.

Science.gov (United States)

Adachi, Paul J C; Hodson, Gordon; Willoughby, Teena; Blank, Carolyn; Ha, Alexandra

2016-03-01

Here we addressed whether even violent video games can improve intergroup attitudes if played cooperatively with an outgroup, in keeping with the Contact Hypothesis. In addition, we examined potential mechanisms of this effect. In Experiment 1 (N = 77), Canadians played a violent video game (Call of Duty: Black Ops) against zombies, either cooperatively or independently (i.e., at the same time but solo) with a (supposed) University of Buffalo participant. As expected, cooperative (vs. solo) play significantly improved outgroup attitudes and pro-outgroup participant behavior, effects explained by heightened 1-group recategorization (i.e., feeling psychologically on the same team and connected with the outgroup member). In Experiment 2 (N = 239), effects of cooperation (vs. solo play) held whether playing a violent or nonviolent video game. Importantly, our findings offer an engaging and pragmatic solution to the pervasive issue of setting up and negotiating opportunities for successful intergroup cooperation. (c) 2016 APA, all rights reserved).

Mathematical modelling of contact of ruled surfaces: theory and practical application

Science.gov (United States)

Panchuk, K. L.; Niteyskiy, A. S.

2016-04-01

In the theory of ruled surfaces there are well known researches of contact of ruled surfaces along their common generator line (Klein image is often used [1]). In this paper we propose a study of contact of non developable ruled surfaces via the dual vector calculus. The advantages of this method have been demonstrated by E. Study, W. Blaschke and D. N. Zeiliger in differential geometry studies of ruled surfaces in space R3 over the algebra of dual numbers. A practical use of contact is demonstrated by the example modeling of the working surface of the progressive tool for tillage.

Measuring Intergroup Attitudes in Community Settings.

Science.gov (United States)

Fisher, Ronald J.

Contemporary social psychology takes a simplistic approach to the conceptualization and measurement of intergroup attitudes. Most definitions involve only the affective component of attitudes, and most measurement devices are restricted self-report, paper and pencil questionnaires. A broader and more flexible approach is required to adequately…

Interracial prison contact: the pros for (socially dominant) cons.

Science.gov (United States)

Hodson, Gordon

2008-06-01

Individuals high in social dominance orientation (SDO; Sidanius & Pratto, 1999) endorse group hierarchies and social inequality. Surprisingly little research has addressed contextual factors associated with reduced intergroup biases among such individuals. The present investigation considers a Person x Situation approach to this question in two British prisons, exploring the contextual factors outlined in the Contact Hypothesis (Allport, 1954). White inmates scoring higher in SDO exhibited significantly less in-group bias when reporting increased contact with Black inmates (Studies 1 & 2), when perceiving that favourable contact conditions are institutionally supported (Study 1), or when experiencing more pleasant personal interactions with Black inmates (Study 2). These SDO x Contact Condition moderation effects were mediated in Study 2: among high-SDO individuals, increased empathy towards Black inmates mediated the relation between contact variables and lower in-group bias. Implications for considering individual differences and empathy in contact settings are considered.

Inter-Group and Intra-Group Assertiveness: Adolescents' Social Skills Following Cultural Transition

Science.gov (United States)

Korem, Anat; Horenczyk, Gabriel; Tatar, Moshe

2012-01-01

The goals of this study were to examine intra-group and inter-group assertiveness among adolescents, and to compare these two domains of assertiveness between cultural groups in Israel. Measures of intra-group and inter-group assertiveness were developed, and questionnaires were administrated to 441 immigrants from the Former Soviet Union (FSU),…

Intergroup Cooperation in Common Pool Resource Dilemmas.

Science.gov (United States)

Sadowski, Jathan; Spierre, Susan G; Selinger, Evan; Seager, Thomas P; Adams, Elizabeth A; Berardy, Andrew

2015-10-01

Fundamental problems of environmental sustainability, including climate change and fisheries management, require collective action on a scale that transcends the political and cultural boundaries of the nation-state. Rational, self-interested neoclassical economic theories of human behavior predict tragedy in the absence of third party enforcement of agreements and practical difficulties that prevent privatization. Evolutionary biology offers a theory of cooperation, but more often than not in a context of discrimination against other groups. That is, in-group boundaries are necessarily defined by those excluded as members of out-groups. However, in some settings human's exhibit behavior that is inconsistent with both rational economic and group driven cooperation of evolutionary biological theory. This paper reports the results of a non-cooperative game-theoretic exercise that models a tragedy of the commons problem in which groups of players may advance their own positions only at the expense of other groups. Students enrolled from multiple universities and assigned to different multi-university identity groups participated in experiments that repeatedly resulted in cooperative outcomes despite intergroup conflicts and expressions of group identity. We offer three possible explanations: (1) students were cooperative because they were in an academic setting; (2) students may have viewed their instructors as the out-group; or (3) the emergence of a small number of influential, ethical leaders is sufficient to ensure cooperation amongst the larger groups. From our data and analysis, we draw out lessons that may help to inform approaches for institutional design and policy negotiations, particularly in climate change management.

Impact of the discovery of crude oil on inter-group relations between ...

African Journals Online (AJOL)

Impact of the discovery of crude oil on inter-group relations between Isoko and her immediate neighbours in the western Niger Delta of Nigeria. ... The article shows that the discovery of crude oil petroleum in the western Niger Delta marked a watershed in the history of intergroup relations in the area. Keywords: Discovery ...

Explaining Gender-Based Language Use: Effects of Gender Identity Salience on References to Emotion and Tentative Language in Intra- and Intergroup Contexts

Science.gov (United States)

Palomares, Nicholas A.

2008-01-01

An experiment tested hypotheses derived from self-categorization theory's explanation for gender-based language use. Under high or low conditions of gender salience, men and women sent e-mail to an ostensible male or female recipient yielding either an intra- or an intergroup setting. Gender salience was manipulated so that the stereotypically…

Aversive racism in Spain: testing the theory

NARCIS (Netherlands)

Wojcieszak, M.

2015-01-01

This study applies the aversive racism framework to Spain and tests whether aversive racism depends on intergroup contact. Relying on a 3 (qualifications) by 3 (ethnicity) experiment, this study finds that aversive racism is especially pronounced against the Mexican job applicant, and emerges among

Combating Prejudice in the Workplace with Contact Theory: The Lived Experiences of Professionals with Disabilities

Directory of Open Access Journals (Sweden)

Paul David Harpur

2014-01-01

Full Text Available People with disabilities often confront barriers in exercising their right to work.  Social model scholarship has recognised that attitude is a key factor in the disablement of people with impairments.  This study reports on 28 semi-structured interviews with professionals with disabilities.  Drawing from their lived experiences and roles in the disability rights movement, the professionals with disabilities interviewed in this study provide unique perspectives on the instances of attitudinal discrimination.  The interviewees discuss the tactics they employ to reduce the negative impact of erroneous stereotypes and the successes of such tactics.  Many of the tactics employed by interviewees reflect strategies discussed in contact theory scholarship.  This study focuses upon contact theory and considers the similarities between this theory and the interventions of interviewees.  Through positing interviewees' tactics in the literature this study is able to analyse possible positive and negative consequences of such interventions.    Keywords: Contact theory, right to work, professionals with disabilities

Ethnicity, Language and Intergroup Relations in Malaysia and Singapore: A Social Psychological Analysis.

Science.gov (United States)

Ward, C.; Hewstone, M.

1985-01-01

Presents a review of literature and a historical and sociopolitical overview of ethnic relations and intergroup processes in Malaysia and Singapore. The paper reviews data on intergroup relations and ethnolinguistics in these countries from a social-psychological perspective, and in terms of assimilation and integration. (SED)

Intergroup Bias in Parliamentary Rule Enforcement

DEFF Research Database (Denmark)

Hjorth, Frederik Georg

2016-01-01

Political actors are often assigned roles requiring them to enforce rules without giving in-groups special treatment. But are such institutional roles likely to be successful? Here, I exploit a special case of exogenously assigned intergroup relations: debates in the Danish Parliament, in which P...... of clear rules, complete observability, and a tradition of parliamentary cooperation....

The evolution of lethal intergroup violence

OpenAIRE

Kelly, Raymond C.

2005-01-01

Recent findings and analyses in evolutionary biology, archaeology, and ethnology provide a favorable conjuncture for examining the evolution of lethal intergroup violence among hominids during the 2.9-million-year Paleolithic time span. Here, I seek to identify and investigate the main turning points in this evolutionary trajectory and to delineate the periodization that follows from this inquiry.

The evolution of lethal intergroup violence.

Science.gov (United States)

Kelly, Raymond C

2005-10-25

Recent findings and analyses in evolutionary biology, archaeology, and ethnology provide a favorable conjuncture for examining the evolution of lethal intergroup violence among hominids during the 2.9-million-year Paleolithic time span. Here, I seek to identify and investigate the main turning points in this evolutionary trajectory and to delineate the periodization that follows from this inquiry.

Jak snižovat předsudky? Teorie meziskupinového kontaktu

Czech Academy of Sciences Publication Activity Database

Graf, Sylvie; Kováčová, Stanislava

2016-01-01

Roč. 60, č. 2 (2016), s. 185-196 ISSN 0009-062X R&D Projects: GA ČR GA13-25656S Institutional support: RVO:68081740 Keywords : intergroup contact * indirect intergroup contact * prejudice * intergroup attitudes * primary transfer effect of intergroup contact * secondary transfer effect of intergroup contact Subject RIV: AN - Psychology Impact factor: 0.242, year: 2016

Using Contact Theory to Assess Staff Perspectives on Training Initiatives of an Intergenerational Programming Intervention.

Science.gov (United States)

Weaver, Raven H; Naar, Jill J; Jarrott, Shannon E

2017-12-25

Project TRIP (Transforming Relationships through Intergenerational Programs) was developed as a sustainable intergenerational community project involving child care participants and elders attending an elder care program or volunteering at the children's program. The project focused on staff development of evidence-based intergenerational practices. To enhance available intervention research, contact theory provided a theoretical framework to explore how staff members' and administrators' perceptions of the intervention influenced their ability to implement programming in social care settings. We used a directed content analysis approach to analyze small group and individual interviews with 32 participants from 6 program sites over 5 years. Participants highlighted inherent challenges and subsequent benefits of academic-community partnerships. Greater on-site presence, open communication, and relationship-building proved critical to improve community partnerships, project fidelity, and program sustainability. When interactions reflected contact theory tenets, collaborators reported positive attitudes toward and interactions with research partners. Contact theory provided a useful framework to understand the researcher-practitioner partnership. Researchers should plan for partnerships that: (a) are supported by authority figures, including staff and participants, (b) utilize a shared expertise approach where partners have equal group status, (c) involve close cooperation; (d) align research and program goals, and (e) foster positive communication through frequent contact using practitioners' preferred methods and including in-person contact. We recommend future intergenerational programming interventions build on a foundation of both theory and practice. © The Author(s) 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Asymmetric intergroup bullying: The enactment and maintenance of societal inequality at work

OpenAIRE

Soylu, Soydan; Sheehy-Skeffington, Jennifer

2015-01-01

What does inequality mean for dysfunctional organizational behaviours, such as workplace bullying? This article argues that workplace bullying can be understood as a manifestation of intergroup dynamics originating beyond the organization. We introduce the construct of asymmetric intergroup bullying: the disproportionate mistreatment of members of low status groups, with the intended effect of enhancing the subordination of that group in society at large. Analysis of data from 38 interviews w...

An empirical analysis of the multimarket contact theory in pharmaceutical markets.

Science.gov (United States)

Coronado, Javier; Jiménez-Martín, Sergi; Marín, Pedro L

2014-07-01

Multimarket contact theory predicts that firms will optimally reduce prices in markets where collusive prices are sustainable and allocate the slack of the corresponding incentive compatibility to increase prices in markets where collusion is not sustainable. Binding price caps in collusive markets will have different effects over the multimarket contact mechanism depending on the severity of the cap. Setting a price cap close to the unregulated case will increase the size of the redistribution of market power whereas stronger regulation will even reduce prices in unregulated markets. Therefore, price regulations aiming at capping prices in a specific market will also affect markets that are not subject to specific mandatory price regulations. We find evidence of the theory predictions using information for nine OECD countries for pharmaceutical markets. Unregulated US markets are shown to respond to the redistribution effect; Canadian markets, known to be subject to soft price regulations, with respect to the former, are shown to be consistent with a stronger redistribution effect. EU markets and Japan are either consistent with the effect of a medium regulation or strong regulation. In this last case multimarket contact cannot explain prices, and these are expected to be lower compared to the unregulated benchmark.

Group Membership, Group Change, and Intergroup Attitudes: A Recategorization Model Based on Cognitive Consistency Principles

Science.gov (United States)

Roth, Jenny; Steffens, Melanie C.; Vignoles, Vivian L.

2018-01-01

The present article introduces a model based on cognitive consistency principles to predict how new identities become integrated into the self-concept, with consequences for intergroup attitudes. The model specifies four concepts (self-concept, stereotypes, identification, and group compatibility) as associative connections. The model builds on two cognitive principles, balance–congruity and imbalance–dissonance, to predict identification with social groups that people currently belong to, belonged to in the past, or newly belong to. More precisely, the model suggests that the relative strength of self-group associations (i.e., identification) depends in part on the (in)compatibility of the different social groups. Combining insights into cognitive representation of knowledge, intergroup bias, and explicit/implicit attitude change, we further derive predictions for intergroup attitudes. We suggest that intergroup attitudes alter depending on the relative associative strength between the social groups and the self, which in turn is determined by the (in)compatibility between social groups. This model unifies existing models on the integration of social identities into the self-concept by suggesting that basic cognitive mechanisms play an important role in facilitating or hindering identity integration and thus contribute to reducing or increasing intergroup bias. PMID:29681878

Group Membership, Group Change, and Intergroup Attitudes: A Recategorization Model Based on Cognitive Consistency Principles

Directory of Open Access Journals (Sweden)

Jenny Roth

2018-04-01

Full Text Available The present article introduces a model based on cognitive consistency principles to predict how new identities become integrated into the self-concept, with consequences for intergroup attitudes. The model specifies four concepts (self-concept, stereotypes, identification, and group compatibility as associative connections. The model builds on two cognitive principles, balance–congruity and imbalance–dissonance, to predict identification with social groups that people currently belong to, belonged to in the past, or newly belong to. More precisely, the model suggests that the relative strength of self-group associations (i.e., identification depends in part on the (incompatibility of the different social groups. Combining insights into cognitive representation of knowledge, intergroup bias, and explicit/implicit attitude change, we further derive predictions for intergroup attitudes. We suggest that intergroup attitudes alter depending on the relative associative strength between the social groups and the self, which in turn is determined by the (incompatibility between social groups. This model unifies existing models on the integration of social identities into the self-concept by suggesting that basic cognitive mechanisms play an important role in facilitating or hindering identity integration and thus contribute to reducing or increasing intergroup bias.

Group Membership, Group Change, and Intergroup Attitudes: A Recategorization Model Based on Cognitive Consistency Principles.

Science.gov (United States)

Roth, Jenny; Steffens, Melanie C; Vignoles, Vivian L

2018-01-01

The present article introduces a model based on cognitive consistency principles to predict how new identities become integrated into the self-concept, with consequences for intergroup attitudes. The model specifies four concepts (self-concept, stereotypes, identification, and group compatibility) as associative connections. The model builds on two cognitive principles, balance-congruity and imbalance-dissonance, to predict identification with social groups that people currently belong to, belonged to in the past, or newly belong to. More precisely, the model suggests that the relative strength of self-group associations (i.e., identification) depends in part on the (in)compatibility of the different social groups. Combining insights into cognitive representation of knowledge, intergroup bias, and explicit/implicit attitude change, we further derive predictions for intergroup attitudes. We suggest that intergroup attitudes alter depending on the relative associative strength between the social groups and the self, which in turn is determined by the (in)compatibility between social groups. This model unifies existing models on the integration of social identities into the self-concept by suggesting that basic cognitive mechanisms play an important role in facilitating or hindering identity integration and thus contribute to reducing or increasing intergroup bias.

Accountability Accentuates Interindividual-Intergroup Discontinuity by Enforcing Parochialism

NARCIS (Netherlands)

Wildschut, T.; Van Horen, F.; Hart, C.

2015-01-01

Interindividual-intergroup discontinuity is the tendency for relations between groups to be more competitive than relations between individuals. We examined whether the discontinuity effect arises in part because group members experience normative pressure to favor the ingroup (parochialism).

Intragroup and intergroup conflict at work, psychological distress, and work engagement in a sample of employees in Japan.

Science.gov (United States)

Tsuno, Kanami; Kawakami, Norito; Inoue, Akiomi; Ishizaki, Masao; Tabata, Masaji; Tsuchiya, Masao; Akiyama, Miki; Kitazume, Akiko; Kuroda, Mitsuyo; Shimazu, Akihito

2009-12-01

The possible associations of intragroup and intergroup conflict at work with psychological distress and work engagement were investigated in a cross-sectional study in a manufacturing factory in Japan. A self-administered questionnaire was sent to all employees, and 255 responses were returned (a response rate of 84%). Data from 247 workers (187 males and 60 females) with no missing values were analyzed. Intragroup and intergroup conflict at work, psychological distress, and work engagement were measured by the NIOSH-GJSQ, K6, and Utrecht Work Engagement Scale (UWES-9), respectively. An ANCOVA was conducted to compare K6 and UWES-9 scores among the tertiles on intragroup conflict or intergroup conflict scores, adjusting for demographic and occupational variables as well as worksite social support, separately for males and females. Intragroup conflict was associated with greater psychological distress for males (p for trend=0.009). Intergroup conflict was marginally significantly associated with psychological distress for both males and females (p for trend=0.050 and 0.051, respectively). Contrary to expectation, intergroup conflict was significantly associated with greater work engagement for females (p for trend=0.024). For males, intragroup and intergroup conflict at work may increase psychological distress; for females, intergroup conflict may increase both psychological distress and work engagement.

Ideology and intergroup inequality : Emerging directions and trends

NARCIS (Netherlands)

Kay, Aaron; Brandt, M.J.

2016-01-01

The authors propose that two guiding frameworks characterize psychological research on the relation between ideology and inequality. The first, called the product approach, focuses on ideologies directly concerned with intergroup relations, in which beliefs about inequality can be considered a

Study effective factors on customer compliance in high contact services based on Bandura social - Cognitive theory

OpenAIRE

zahra asadi; bahman hajipour

2014-01-01

In today's competitive world, all market participants ranging from individuals, organizations should be looking for ways to success in the market. The secret to success high contact service providers as important part of market participants is, compliance and follow customers of high contact service providers the instructions and guidance. In this paper, a model based on Bandura social - Cognitive theory has Provided to customer compliance . According Bandura social - Cognitive theory and t...

The multicultural workplace: interactive acculturation and intergroup relations

NARCIS (Netherlands)

Oerlemans, W.G.M.; Peeters, M.C.W.

2010-01-01

Purpose : – The paper's aim is to introduce the interactive acculturation model (IAM) of Bourhis et al. to predict how disconcordance in acculturation orientations between host community and immigrant workers relates to the quality of intergroup work-relations. Design/methodology/approach : – The

Can Caring Create Prejudice? An Investigation of Positive and Negative Intergenerational Contact in Care Settings and the Generalisation of Blatant and Subtle Age Prejudice to Other Older People.

Science.gov (United States)

Drury, Lisbeth; Abrams, Dominic; Swift, Hannah J; Lamont, Ruth A; Gerocova, Katarina

2017-01-01

Caring is a positive social act, but can it result in negative attitudes towards those cared for, and towards others from their wider social group? Based on intergroup contact theory, we tested whether care workers' (CWs) positive and negative contact with old-age care home residents (CHRs) predicts prejudiced attitudes towards that group, and whether this generalises to other older people. Fifty-six CWs were surveyed about their positive and negative contact with CHRs and their blatant and subtle attitudes (humanness attributions) towards CHRs and older adults. We tested indirect paths from contact with CHRs to attitudes towards older adults via attitudes towards CHRs. Results showed that neither positive nor negative contact generalised blatant ageism. However, the effect of negative, but not positive, contact on the denial of humanness to CHRs generalised to subtle ageism towards older adults. This evidence has practical implications for management of CWs' work experiences and theoretical implications, suggesting that negative contact with a subgroup generalises the attribution of humanness to superordinate groups. Because it is difficult to identify and challenge subtle prejudices such as dehumanisation, it may be especially important to reduce negative contact. © 2016 The Authors. Journal of Community & Applied Social Psychology Published by John Wiley & Sons Ltd.

Exploring the mental health benefits of participation in an Australian anti-racism intervention.

Science.gov (United States)

Kelaher, Margaret; Ferdinand, Angeline S; Paradies, Yin; Warr, Deborah

2018-02-01

There is a vast body of research demonstrating the deleterious effects of racism on health. Despite this, there is limited research that considers the health benefits of anti-racism interventions. We assess the mental health effects for young people participating in an anti-racism intervention that was based on the principles of intergroup contact theory and delivered through five projects addressing specific issues and contexts. An evaluation of the intervention used a before-and-after design. The analyses reported here focus on data collected from participants who completed both pre- and post-intervention surveys (n = 246). Analyses examine the characteristics of participants, the environment for intergroup contact (equal status between ethnic groups, shared goals, co-operation and institutional support for intergroup relationships) and basic psychological needs (competence, relatedness and autonomy) as defined by Self-Determination Theory. The results suggest that the projects met the criteria for promoting positive intergroup contact. There was also evidence that participants' involvement in these projects had positive effects on their autonomy, with particular improvements among people with ethnicities other than 'Australian'. The findings suggest that anti-racism interventions can have positive mental health effects for participants. These benefits redress some of the individual-level effects of racism experiences by supporting young people to develop confidence and self-esteem. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Cultural Diversity in Military Teams: Which Factors Influence Effectiveness?

Science.gov (United States)

2008-12-01

TNO-DV2008A513 Opdrachtnummer Datum december 2008 Auteur (s) dr. I.M. Wetzer dr. D.A. van Hemert Rubricering rapport Ongerubriceerd TM0...been reported. Based on Allport’s (1954) intergroup contact theory , positive effects of intercultural contact may occur under certain conditions...diversity on perceived team effectiveness, but only at the 11-30% level. In contrast, social identity theory would lead one to expect negative effects of

The development of bystander intentions and social-moral reasoning about intergroup verbal aggression.

Science.gov (United States)

Palmer, Sally B; Rutland, Adam; Cameron, Lindsey

2015-11-01

A developmental intergroup approach was taken to examine the development of prosocial bystander intentions among children and adolescents. Participants as bystanders (N = 260) aged 8-10 and 13-15 years were presented with scenarios of direct aggression between individuals from different social groups (i.e., intergroup verbal aggression). These situations involved either an ingroup aggressor and an outgroup victim or an outgroup aggressor and an ingroup victim. This study focussed on the role of intergroup factors (group membership, ingroup identification, group norms, and social-moral reasoning) in the development of prosocial bystander intentions. Findings showed that prosocial bystander intentions declined with age. This effect was partially mediated by the ingroup norm to intervene and perceived severity of the verbal aggression. However, a moderated mediation analysis showed that only when the victim was an ingroup member and the aggressor an outgroup member did participants become more likely with age to report prosocial bystander intentions due to increased ingroup identification. Results also showed that younger children focussed on moral concerns and adolescents focussed more on psychological concerns when reasoning about their bystander intention. These novel findings help explain the developmental decline in prosocial bystander intentions from middle childhood into early adolescence when observing direct intergroup aggression. © 2015 The British Psychological Society.

Mass social contact interventions and their effect on mental health related stigma and intended discrimination.

Science.gov (United States)

Evans-Lacko, Sara; London, Jillian; Japhet, Sarah; Rüsch, Nicolas; Flach, Clare; Corker, Elizabeth; Henderson, Claire; Thornicroft, Graham

2012-06-28

Stigma and discrimination associated with mental health problems is an important public health issue, and interventions aimed at reducing exposure to stigma and discrimination can improve the lives of people with mental health problems. Social contact has long been considered to be one of the most effective strategies for improving inter-group relations. For this study, we assess the impact of a population level social contact intervention among people with and without mental health problems. This study investigated the impact of social contact and whether presence of specific facilitating factors (equal status, common goals, cooperation and friendship potential): (1) improves intended stigmatising behaviour; (2) increases future willingness to disclose a mental health problem; and (3) promotes behaviours associated with anti-stigma campaign engagement. Two mass participation social contact programmes within England's Time to Change campaign were evaluated via a 2-part questionnaire. 403 participants completed initial questionnaires (70% paper, 30% online) and 83 completed follow-up questionnaires online 4-6 weeks later. This study investigated the impact of social contact and whether presence of specific facilitating factors (equal status, common goals, cooperation and friendship potential): (1) improves intended stigmatising behaviour; (2) increases future willingness to disclose a mental health problem; and (3) promotes behaviours associated with anti-stigma campaign engagement. Two mass participation social contact programmes within England's Time to Change campaign were evaluated via a 2-part questionnaire. 403 participants completed initial questionnaires (70% paper, 30% online) and 83 completed follow-up questionnaires online 4-6 weeks later. Campaign events facilitated meaningful intergroup social contact between individuals with and without mental health problems. Presence of facilitating conditions predicted improved stigma-related behavioural intentions

Cultural Studies of Education: Filming Fluid Subjectivities in Indonesian Universities

Science.gov (United States)

Logli, Chiara

2016-01-01

This article focuses on the Indonesian film "Cin(T)a," which features the interfaith and multiethnic love between two college students. I apply intergroup contact theory, critical pedagogy and grounded cosmopolitanism to the reading of the movie in order to demonstrate two key points. First, higher education is a contact zone, where…

Modeling of various contact theories for the manipulation of different biological micro/nanoparticles based on AFM

Science.gov (United States)

Korayem, M. H.; Taheri, M.

2014-01-01

In this article, the modeling of various contact theories to be applied in the biomanipulation of different micro/nanoparticles based on the atomic force microscope has been studied, and the effect of adhesion force in different contact models on indentation depth and contact angle between tip and substrate has been explored for the target biological micro/nanoparticle. The contact models used in this research include the Hertz, JKR, DMT, BCP, COS, PT, and the SUN models. Also, the target particles comprise the biological micro/nanoparticles of DNA, yeast, platelet, and nanobacterium. Previous research works have investigated the contact models for the manipulation of non-biological gold micro/nanoparticles in the air environment. Since in a real biomanipulation situation, the biological micro/nanoparticles are displaced in biological environments; in this article, various contact theories for the biomanipulation of biological micro/nanoparticles in different biological environments have been modeled and compared for the first time. The results of modeling indicate that the use of Hertz contact model in analyzing the biomanipulation of biological nanoparticles is not appropriate, because it does not take the adhesion force into consideration and thus produces a significant error. Also, all the six contact models developed in this article show larger deformations for studied bionanoparticles in comparison to the gold nanoparticles, which can be justified with regards to the mechanical properties of gold.

Negotiating power: agenda ordering and the willingness to negotiate in asymmetric intergroup conflicts.

Science.gov (United States)

Kteily, Nour; Saguy, Tamar; Sidanius, James; Taylor, Donald M

2013-12-01

In this research, we investigated how group power influences the way members of groups in asymmetrical conflict approach intergroup negotiations. Drawing on theories of negotiations and of intergroup power, we predicted that group power would interact with features of the proposed negotiating agenda to influence willingness to come to the table. Based on the negotiation literature, we focused on 2 types of sequential negotiation agendas: 1 beginning with the discussion of consequential issues before less consequential issues (consequential first) and 1 leaving the discussion of consequential issues until after less consequential issues are discussed (consequential later). Because they are motivated to advance changes to their disadvantaged status quo, we expected low-power group members to favor consequential first over consequential later invitations to negotiate. High-power group members, motivated to protect their advantage, were expected to show the reverse preference. Converging evidence from 5 experiments involving real-world and experimental groups supported these predictions. Across studies, participants received an invitation to negotiate from the other group involving either a consequential first or consequential later agenda. Low-power group members preferred consequential first invitations because these implied less stalling of change to the status quo, and high-power group members preferred consequential later invitations because these invitations seemed to pose less threat to their position. Theoretical and practical implications for negotiations research and conflict resolution are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Political ideology and American intergroup discrimination: A patriotism perspective.

Science.gov (United States)

L Hoyt, Crystal; Goldin, Aleah

2016-01-01

In this research we demonstrate the powerful role of ingroup favoritism, rather than hostility, in American intergroup biases. Specifically, we take a novel perspective to understanding the relationship between political ideology and discrimination against ethnic-minority Americans by focusing on the role of patriotism. Across three studies, we show that political ideology is a strong predictor of resource allocation biases, and this effect is mediated by American patriotism and not by prejudice or nationalism. Conservatives report greater levels of patriotism than liberals, and patriotism is associated with donating more to American, as opposed to ethnic-minority American, organizations. We further show that the link between patriotism and partiality to the national group is mediated by stronger "American = White" associations. These findings have important implications for intergroup relations and diversity-related policy issues in the United States.

Density-functional theory in one dimension for contact-interacting fermions

International Nuclear Information System (INIS)

Magyar, R.J.; Burke, K.

2004-01-01

A density-functional theory is developed for fermions in one dimension, interacting via a δ function. Such systems provide a natural testing ground for questions of principle, as the local-density approximation should be highly accurate since for this interaction type the exchange contribution to the local-density approximation is intrinsically self-interaction-free. The exact-exchange contribution to the total energy is a local functional of the density. A local-density approximation for correlation is obtained using perturbation theory and Bethe ansatz results for the one-dimensional contact-interacting uniform Fermi gas. The ground-state energies are calculated for two finite systems, the analogs of helium and of Hooke's atom. The local-density approximation is shown to be excellent as expected

Contact mechanics: contact area and interfacial separation from small contact to full contact

International Nuclear Information System (INIS)

Yang, C; Persson, B N J

2008-01-01

We present a molecular dynamics study of the contact between a rigid solid with a randomly rough surface and an elastic block with a flat surface. The numerical calculations mainly focus on the contact area and the interfacial separation from small contact (low load) to full contact (high load). For a small load the contact area varies linearly with the load and the interfacial separation depends logarithmically on the load. For a high load the contact area approaches the nominal contact area (i.e. complete contact), and the interfacial separation approaches zero. The numerical results have been compared with analytical theory and experimental results. They are in good agreement with each other. The present findings may be very important for soft solids, e.g. rubber, or for very smooth surfaces, where complete contact can be reached at moderately high loads without plastic deformation of the solids

And What About Siblings? A Longitudinal Analysis of Sibling Effects on Youth's Intergroup Attitudes.

Science.gov (United States)

Eckstein, Katharina; Šerek, Jan; Noack, Peter

2018-02-01

Within the process of political socialization, the family is of particular importance. Apart from parents, however, little is known about the role of other close family members. The present study examined if siblings affect each other's intergroup attitudes (i.e., intolerance towards immigrants, social dominance orientation). Drawing on a sample of 362 sibling dyads (older siblings: M age  = 17.77, 53.6% female; younger siblings: M age  = 13.61, 61.3% female), the results showed that older siblings' intergroup attitudes predicted younger siblings' attitudes, but this effect was moderated by gender. Specifically, older siblings' intolerance and social dominance orientation were only found to affect their younger sisters, yet not their younger brothers. Although younger siblings' intergroup attitudes had no main effect on older siblings, a significant moderation by age indicated that younger siblings affected older siblings' social dominance orientation with increasing age. These moderation effects of age and gender were not mediated by the quality of family relationships. The findings also remained the same when parental intergroup attitudes were taken into account. While siblings were generally identified as an important agent of political socialization in youth, the results also highlight the necessity to further examine the mechanism that either facilitate or hinder sibling effects.

Contact with Counter-Stereotypical Women Predicts Less Sexism, Less Rape Myth Acceptance, Less Intention to Rape (in Men) and Less Projected Enjoyment of Rape (in Women).

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Taschler, Miriam; West, Keon

2017-01-01

Intergroup contact-(positive) interactions with people from different social groups-is a widely researched and strongly supported prejudice-reducing mechanism shown to reduce prejudice against a wide variety of outgroups. However, no known previous research has investigated whether intergroup contact can also reduce sexism against women. Sexism has an array of negative outcomes. One of the most detrimental and violent ones is rape, which is both justified and downplayed by rape myth acceptance. We hypothesised that more frequent, higher quality contact with counter-stereotypical women would predict lower levels of sexism and thus less rape myth acceptance (in men) and less sexualised projected responses to rape (in women). Two studies using online surveys with community samples supported these hypotheses. In Study 1, 170 male participants who experienced more positive contact with counter-stereotypical women reported less intention to rape. Similarly, in Study 2, 280 female participants who experienced more positive contact with counter-stereotypical women reported less projected sexual arousal at the thought of being raped. Thus, the present research is the first known to show that contact could be a potential tool to combat sexism, rape myth acceptance, intentions to rape in men, and sexualisation of rape by women.

Multicultural experiences reduce intergroup bias through epistemic unfreezing.

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Tadmor, Carmit T; Hong, Ying-Yi; Chao, Melody M; Wiruchnipawan, Fon; Wang, Wei

2012-11-01

In 6 studies, we systematically explored for the 1st time the ameliorative effects of multicultural experience on intergroup bias and investigated the role of epistemic unfreezing as the motivational mechanism underlying these effects. We found that multicultural exposure led to a reduction in stereotype endorsement (Studies 1, 4, and 6), symbolic racism (Study 5), and discriminatory hiring decisions (Study 2). We further demonstrated that experimental exposure to multicultural experience caused a reduction in need for cognitive closure (NFCC; Studies 3 and 6) and that the ameliorative effects of multiculturalism experience on intergroup bias were fully mediated by lower levels of NFCC (Studies 4, 5, and 6). The beneficial effects of multiculturalism were found regardless of the targeted stereotype group (African Americans, Ethiopians, homosexuals, and native Israelis), regardless of whether multicultural experience was measured or manipulated, and regardless of the population sampled (Caucasian Americans or native Israelis), demonstrating the robustness of this phenomenon. Overall, these results demonstrate that multicultural experience plays a critical role in increasing social tolerance through its relationship to motivated cognitive processes.

Differentiating in-group favoritism from shared reality in intergroup perception.

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Dimdins, Girts; Montgomery, Henry

2004-11-01

Two basic factors influence mutual ratings of social groups: in-group favoritism (related to the evaluative aspects of a rating) and the perception of shared reality (related to the descriptive aspects). In two studies, we examine the usefulness of Peabody's (1968) method of separating evaluative and descriptive aspects of rating in intergroup judgments. In Study 1, Latvian and Russian students made different evaluations of both groups, but the same groups agreed on the descriptive ratings. In Study 2, male and female psychology students rated each other from own, in-group, and out-group perspectives. The participants did not show any in-group favoritism in their own ratings, but they expected their fellow students to be in-group biased. The participants agreed on the descriptive ratings of both groups. The results demonstrate that shared reality influences intergroup ratings, despite differences in evaluations.

Mass social contact interventions and their effect on mental health related stigma and intended discrimination

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Evans-Lacko Sara

2012-06-01

Full Text Available Abstract Background Stigma and discrimination associated with mental health problems is an important public health issue, and interventions aimed at reducing exposure to stigma and discrimination can improve the lives of people with mental health problems. Social contact has long been considered to be one of the most effective strategies for improving inter-group relations. For this study, we assess the impact of a population level social contact intervention among people with and without mental health problems. Methods This study investigated the impact of social contact and whether presence of specific facilitating factors (equal status, common goals, cooperation and friendship potential: (1 improves intended stigmatising behaviour; (2 increases future willingness to disclose a mental health problem; and (3 promotes behaviours associated with anti-stigma campaign engagement. Two mass participation social contact programmes within England’s Time to Change campaign were evaluated via a 2-part questionnaire. 403 participants completed initial questionnaires (70% paper, 30% online and 83 completed follow-up questionnaires online 4–6 weeks later. Results This study investigated the impact of social contact and whether presence of specific facilitating factors (equal status, common goals, cooperation and friendship potential: (1 improves intended stigmatising behaviour; (2 increases future willingness to disclose a mental health problem; and (3 promotes behaviours associated with anti-stigma campaign engagement. Two mass participation social contact programmes within England’s Time to Change campaign were evaluated via a 2-part questionnaire. 403 participants completed initial questionnaires (70% paper, 30% online and 83 completed follow-up questionnaires online 4–6 weeks later. Campaign events facilitated meaningful intergroup social contact between individuals with and without mental health problems. Presence of facilitating conditions

Evolution and the psychology of intergroup conflict: the male warrior hypothesis.

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McDonald, Melissa M; Navarrete, Carlos David; Van Vugt, Mark

2012-03-05

The social science literature contains numerous examples of human tribalism and parochialism-the tendency to categorize individuals on the basis of their group membership, and treat ingroup members benevolently and outgroup members malevolently. We hypothesize that this tribal inclination is an adaptive response to the threat of coalitional aggression and intergroup conflict perpetrated by 'warrior males' in both ancestral and modern human environments. Here, we describe how male coalitional aggression could have affected the social psychologies of men and women differently and present preliminary evidence from experimental social psychological studies testing various predictions from the 'male warrior' hypothesis. Finally, we discuss the theoretical implications of our research for studying intergroup relations both in humans and non-humans and discuss some practical implications.

How does social essentialism affect the development of inter-group relations?

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Rhodes, Marjorie; Leslie, Sarah-Jane; Saunders, Katya; Dunham, Yarrow; Cimpian, Andrei

2018-01-01

Psychological essentialism is a pervasive conceptual bias to view categories as reflecting something deep, stable, and informative about their members. Scholars from diverse disciplines have long theorized that psychological essentialism has negative ramifications for inter-group relations, yet little previous empirical work has experimentally tested the social implications of essentialist beliefs. Three studies (N = 127, ages 4.5-6) found that experimentally inducing essentialist beliefs about a novel social category led children to share fewer resources with category members, but did not lead to the out-group dislike that defines social prejudice. These findings indicate that essentialism negatively influences some key components of inter-group relations, but does not lead directly to the development of prejudice. © 2017 John Wiley & Sons Ltd.

Destined to die but not to wage war: how existential threat can contribute to escalation or de-escalation of violent intergroup conflict.

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Jonas, Eva; Fritsche, Immo

2013-10-01

War means threat to people's lives. Research derived from terror management theory (TMT) illustrates that the awareness of death leads people to defend cultural ingroups and their worldviews to attain a sense of symbolic immortality and thereby buffer existential anxiety. This can result in hostile effects of mortality salience (MS), such as derogation of outgroup members, prejudice, stereotyping, aggression, and racism, which, in turn, can lead to the escalation of violent intergroup conflict and, thus, the escalation of war. Yet, escalation of destructive conflict following MS is not automatic. Instead, research on TMT suggests that MS does not necessarily result in conflict and intolerance but can also foster positive tendencies, such as intergroup fairness or approval of pacifism, depending on how existential threat is perceived, whether the need for symbolic self-transcendence is satisfied, which social norms are salient, and how social situations are interpreted. In the present article, we review current TMT research with the aim of reconciling the seemingly contradictory findings of hostile and peaceful reactions to reminders of death. We present a terror management model of escalation and de-escalation of violent intergroup conflicts, which takes into account the interaction between threat salience and features of the social situation. We also discuss possible intervention strategies to override detrimental consequences of existential threat and argue that war is not the inevitable consequence of threat. PsycINFO Database Record (c) 2013 APA, all rights reserved

Intergroup aggression in chimpanzees and war in nomadic hunter-gatherers: evaluating the chimpanzee model.

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Wrangham, Richard W; Glowacki, Luke

2012-03-01

Chimpanzee and hunter-gatherer intergroup aggression differ in important ways, including humans having the ability to form peaceful relationships and alliances among groups. This paper nevertheless evaluates the hypothesis that intergroup aggression evolved according to the same functional principles in the two species-selection favoring a tendency to kill members of neighboring groups when killing could be carried out safely. According to this idea chimpanzees and humans are equally risk-averse when fighting. When self-sacrificial war practices are found in humans, therefore, they result from cultural systems of reward, punishment, and coercion rather than evolved adaptations to greater risk-taking. To test this "chimpanzee model," we review intergroup fighting in chimpanzees and nomadic hunter-gatherers living with other nomadic hunter-gatherers as neighbors. Whether humans have evolved specific psychological adaptations for war is unknown, but current evidence suggests that the chimpanzee model is an appropriate starting point for analyzing the biological and cultural evolution of warfare.

Sources of implicit and explicit intergroup race bias among African-American children and young adults.

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Bentley L Gibson

Full Text Available Implicit intergroup bias emerges early in development, are typically pro-ingroup, and remain stable across the lifespan. Such findings have been interpreted in terms of an automatic ingroup bias similar to what is observed with minimal groups paradigms. These studies are typically conducted with groups of high cultural standing (e.g., Caucasians in North America and Europe. Research conducted among culturally lower status groups (e.g., African-Americans, Latino-Americans reveals a notable absence of an implicit ingroup bias. Understanding the environmental factors that contribute to the absence of an implicit ingroup bias among people from culturally lower status groups is critical for advancing theories of implicit intergroup cognition. The present study aimed to elucidate the factors that shape racial group bias among African-American children and young adults by examining their relationship with age, school composition (predominantly Black schools or racially mixed schools, parental racial attitudes and socialization messages among African-American children (N = 86 and young adults (N = 130. Age, school-type and parents' racial socialization messages were all found to be related to the strength of pro-Black (ingroup bias. We also found that relationships between implicit and explicit bias and frequency of parents' racial socialization messages depended on the type of school participants attended. Our results highlight the importance of considering environmental factors in shaping the magnitude and direction of implicit and explicit race bias among African-Americans rather than treating them as a monolithic group.

Accountability Accentuates Interindividual-Intergroup Discontinuity by Enforcing Parochialism

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Wildschut, T.; Van Horen, F.; Hart, C.

2015-01-01

Interindividual-intergroup discontinuity is the tendency for relations between groups to be more competitive than relations between individuals. We examined whether the discontinuity effect arises in part because group members experience normative pressure to favor the ingroup (parochialism). Building on the notion that accountability enhances normative pressure, we hypothesized that the discontinuity effect would be larger when accountability is present (compared to absent). A prisoner’s dil...

Elastic contact mechanics: percolation of the contact area and fluid squeeze-out.

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Persson, B N J; Prodanov, N; Krick, B A; Rodriguez, N; Mulakaluri, N; Sawyer, W G; Mangiagalli, P

2012-01-01

The dynamics of fluid flow at the interface between elastic solids with rough surfaces depends sensitively on the area of real contact, in particular close to the percolation threshold, where an irregular network of narrow flow channels prevails. In this paper, numerical simulation and experimental results for the contact between elastic solids with isotropic and anisotropic surface roughness are compared with the predictions of a theory based on the Persson contact mechanics theory and the Bruggeman effective medium theory. The theory predictions are in good agreement with the experimental and numerical simulation results and the (small) deviation can be understood as a finite-size effect. The fluid squeeze-out at the interface between elastic solids with randomly rough surfaces is studied. We present results for such high contact pressures that the area of real contact percolates, giving rise to sealed-off domains with pressurized fluid at the interface. The theoretical predictions are compared to experimental data for a simple model system (a rubber block squeezed against a flat glass plate), and for prefilled syringes, where the rubber plunger stopper is lubricated by a high-viscosity silicon oil to ensure functionality of the delivery device. For the latter system we compare the breakloose (or static) friction, as a function of the time of stationary contact, to the theory prediction.

Interaction location outweighs the competitive advantage of numerical superiority in Cebus capucinus intergroup contests.

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Crofoot, Margaret C; Gilby, Ian C; Wikelski, Martin C; Kays, Roland W

2008-01-15

Numerical superiority confers a competitive advantage during contests among animal groups, shaping patterns of resource access, and, by extension, fitness. However, relative group size does not always determine the winner of intergroup contests. Smaller, presumably weaker social groups often defeat their larger neighbors, but how and when they are able to do so remains poorly understood. Models of competition between individuals suggest that location may influence contest outcome. However, because of the logistical difficulties of studying intergroup interactions, previous studies have been unable to determine how contest location and group size interact to shape relationships among groups. We address this question by using an automated radio telemetry system to study intergroup interactions among six capuchin monkey (Cebus capucinus) social groups of varying sizes. We find that the odds of winning increase with relative group size; one additional group member increases the odds of winning an interaction by 10%. However, this effect is not uniform across space; with each 100 m that a group moves away from the center of its home range, its odds of winning an interaction decrease by 31%. We demonstrate that contest outcome depends on an interaction between group size and location, such that small groups can defeat much larger groups near the center of their home range. The tendency of resident groups to win contests may help explain how small groups persist in areas with intense intergroup competition.

Asymmetry within social groups: division of labour and intergroup competition.

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Barker, J L; Loope, K J; Reeve, H K

2016-03-01

Social animals vary in their ability to compete with group members over shared resources and also vary in their cooperative efforts to produce these resources. Competition among groups can promote within-group cooperation, but many existing models of intergroup cooperation do not explicitly account for observations that group members invest differentially in cooperation and that there are often within-group competitive or power asymmetries. We present a game theoretic model of intergroup competition that investigates how such asymmetries affect within-group cooperation. In this model, group members adopt one of two roles, with relative competitive efficiency and the number of individuals varying between roles. Players in each role make simultaneous, coevolving decisions. The model predicts that although intergroup competition increases cooperative contributions to group resources by both roles, contributions are predominantly from individuals in the less competitively efficient role, whereas individuals in the more competitively efficient role generally gain the larger share of these resources. When asymmetry in relative competitive efficiency is greater, a group's per capita cooperation (averaged across both roles) is higher, due to increased cooperation from the competitively inferior individuals. For extreme asymmetry in relative competitive efficiency, per capita cooperation is highest in groups with a single competitively superior individual and many competitively inferior individuals, because the latter acquiesce and invest in cooperation rather than within-group competition. These predictions are consistent with observed features of many societies, such as monogynous Hymenoptera with many workers and caste dimorphism. © 2015 The Authors. Journal of Evolutionary Biology published by John Wiley & Sons Ltd on behalf of European Society for Evolutionary Biology.

The Ties that Bind and Those that Don't: Toward Reconciling Group Threat and Contact Theories of Prejudice

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Dixon, Jeffrey C.

2006-01-01

Does interracial/interethnic propinquity breed hostility or harmony? Group threat and contact theories generally answer hostility and harmony, respectively. The author proposes that a historically and culturally rooted racial/ethnic hierarchy differentially shapes whites' present-day threat of, contact with, and ultimately, prejudice towards…

Why are all the white (Asian) kids sitting together in the cafeteria? Resegregation and the role of intergroup attributions and norms.

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Ramiah, Ananthi Al; Schmid, Katharina; Hewstone, Miles; Floe, Christina

2015-03-01

Over three studies, we identified the phenomenon of ethnic 'resegregation' and assessed the extent to which it was predicted by attributions and norms, among other variables. Study 1, an observational study, showed extensive resegregation between White and Asian students in the cafeteria of a highly mixed school. In Study 2, we found evidence of attributional correspondence for White students, who attributed both their own and the outgroup's contact avoidance more to a lack of interest than fear of rejection, whereas Asian students attributed the outgroup's contact avoidance more to lack of interest, but preferred neither explanation of their own avoidance. In Study 3, we observed a pattern of attributional correspondence among both White and Asian students who attributed both their own and the outgroup's inaction in a hypothetical intergroup cafeteria scenario more to a lack of interest than fear of rejection. Study 3 also demonstrated longitudinally, for both groups, that own lack of interest in the outgroup reduced likelihood of cafeteria contact, whereas having outgroup friends and perceiving positive ingroup norms promoted it. In addition, positive outgroup norms promoted likelihood of cafeteria contact only for Asian students. We discuss how an understanding of the factors driving resegregation is critical to effectively realizing the potential of desegregated settings. © 2014 The British Psychological Society.

Nonlinear vibration of rectangular atomic force microscope cantilevers by considering the Hertzian contact theory

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Sadeghi, A., E-mail: a_sadeghi@srbiau.ac.ir [Islamic Azad Univ., Dept. of Mechanical and Aerospace Engineering, Science and Research Branch, Tehran (Iran, Islamic Republic of); Zohoor, H. [Sharif Univ. of Technology, Center of Excellence in Design, Robotics and Automation, Tehran (Iran, Islamic Republic of); The Academy of Sciences if I.R. Iran (Iran, Islamic Republic of)

2010-05-15

The nonlinear flexural vibration for a rectangular atomic force microscope cantilever is investigated by using Timoshenko beam theory. In this paper, the normal and tangential tip-sample interaction forces are found from a Hertzian contact model and the effects of the contact position, normal and lateral contact stiffness, tip height, thickness of the beam, and the angle between the cantilever and the sample surface on the nonlinear frequency to linear frequency ratio are studied. The differential quadrature method is employed to solve the nonlinear differential equations of motion. The results show that softening behavior is seen for most cases and by increasing the normal contact stiffness, the frequency ratio increases for the first mode, but for the second mode, the situation is reversed. The nonlinear-frequency to linear-frequency ratio increases by increasing the Timoshenko beam parameter, but decreases by increasing the contact position for constant amplitude for the first and second modes. For the first mode, the frequency ratio decreases by increasing both of the lateral contact stiffness and the tip height, but increases by increasing the angle α between the cantilever and sample surface. (author)

The Quantified Characterization Method of the Micro-Macro Contacts of Three-Dimensional Granular Materials on the Basis of Graph Theory.

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Guan, Yanpeng; Wang, Enzhi; Liu, Xiaoli; Wang, Sijing; Luan, Hebing

2017-08-03

We have attempted a multiscale and quantified characterization method of the contact in three-dimensional granular material made of spherical particles, particularly in cemented granular material. Particle contact is defined as a type of surface contact with voids in its surroundings, rather than a point contact. Macro contact is a particle contact set satisfying the restrictive condition of a two-dimensional manifold with a boundary. On the basis of graph theory, two dual geometrical systems are abstracted from the granular pack. The face and the face set, which satisfies the two-dimensional manifold with a boundary in the solid cell system, are extracted to characterize the particle contact and the macro contact, respectively. This characterization method is utilized to improve the post-processing in DEM (Discrete Element Method) from a micro perspective to describe the macro effect of the cemented granular material made of spherical particles. Since the crack has the same shape as its corresponding contact, this method is adopted to characterize the crack and realize its visualization. The integral failure route of the sample can be determined by a graph theory algorithm. The contact force is assigned to the weight value of the face characterizing the particle contact. Since the force vectors can be added, the macro contact force can be solved by adding the weight of its corresponding faces.

Prediction of static friction coefficient in rough contacts based on the junction growth theory

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Spinu, S.; Cerlinca, D.

2017-08-01

The classic approach to the slip-stick contact is based on the framework advanced by Mindlin, in which localized slip occurs on the contact area when the local shear traction exceeds the product between the local pressure and the static friction coefficient. This assumption may be too conservative in the case of high tractions arising at the asperities tips in the contact of rough surfaces, because the shear traction may be allowed to exceed the shear strength of the softer material. Consequently, the classic frictional contact model is modified in this paper so that gross sliding occurs when the junctions formed between all contacting asperities are independently sheared. In this framework, when the contact tractions, normal and shear, exceed the hardness of the softer material on the entire contact area, the material of the asperities yields and the junction growth process ends in all contact regions, leading to gross sliding inception. This friction mechanism is implemented in a previously proposed numerical model for the Cattaneo-Mindlin slip-stick contact problem, which is modified to accommodate the junction growth theory. The frictionless normal contact problem is solved first, then the tangential force is gradually increased, until gross sliding inception. The contact problems in the normal and in the tangential direction are successively solved, until one is stabilized in relation to the other. The maximum tangential force leading to a non-vanishing stick area is the static friction force that can be sustained by the rough contact. The static friction coefficient is eventually derived as the ratio between the latter friction force and the normal force.

Admiration regulates social hierarchy: Antecedents, dispositions, and effects on intergroup behavior.

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Sweetman, Joseph; Spears, Russell; Livingstone, Andrew G; Manstead, Antony S R

2013-05-01

In four studies, we report evidence that admiration affects intergroup behaviors that regulate social hierarchy. We demonstrate that manipulating the legitimacy of status relations affects admiration for the dominant and that this emotion negatively predicts political action tendencies aimed at social change. In addition, we show that greater warmth and competence lead to greater admiration for an outgroup, which in turn positively predicts deferential behavior and intergroup learning. We also demonstrate that, for those with a disposition to feel admiration, increasing admiration for an outgroup decreases willingness to take political action against that outgroup. Finally, we show that when the object of admiration is a subversive "martyr," admiration positively predicts political action tendencies and behavior aimed at challenging the status quo. These findings provide the first evidence for the important role of admiration in regulating social hierarchy.

The apple does not fall far from the tree, or does it? A meta-analysis of parent-child similarity in intergroup attitudes.

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Degner, Juliane; Dalege, Jonas

2013-11-01

Understanding the formation of prejudice, stereotypes, and discrimination has long been a core topic of social psychology. Since the seminal theorizing by Allport in 1954, different views on childhood origins of prejudice have been discussed, in which the role of parental socialization varies on a scale from fundamental to negligible. This meta-analysis integrates the available empirical evidence of the past 60 years and critically discusses the current state of knowledge on parental socialization of intergroup attitudes. A random-effects model analysis of data from 131 studies on over 45,000 parent-child dyads indicated a significant medium-sized average effect size for the correlation between parental and child intergroup attitudes. The average effect size was related to study-specific variables, such as the source of parental attitude report (self vs. child reported), the conceptual overlap between measures, and the privacy of assessment. We also found significant moderations by ingroup status and size as well as child age. The latter was, however, mediated by measurement overlap. No significant effect size differences were found in relation to different components of intergroup attitudes (i.e., affective, cognitive, behavioral), nor to child or parent gender. The results unequivocally demonstrate that parent-child attitudes are related throughout childhood and adolescence. We discuss in detail whether and to what extent this interrelation can be interpreted as an indicator of parent-child socialization to allow a critical evaluation of the available contradicting theories. We furthermore address limitations of the available research and the current meta-analysis and derive implications and suggestions for future research. © 2013 American Psychological Association

Secondary transfer effects of interracial contact: the moderating role of social status.

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Bowman, Nicholas A; Griffin, Tiffany M

2012-01-01

The contact hypothesis asserts that intergroup attitudes can be improved when groups have opportunities to interact with each other. Recent research extending the contact hypothesis suggests that contact with a primary outgroup can decrease bias toward outgroups not directly involved in the interaction, which is known as the secondary transfer effect (STE). The present study contributes to growing research on STEs by investigating effects among Asian, Black, Hispanic, and White undergraduate students (N = 3,098) attending 28 selective colleges and universities. Using hierarchical linear modeling, our results reveal numerous positive STEs among Asian, Black, and Hispanic college students. No significant STEs were observed among White students. Mediated moderation analyses support an attitude generalization mechanism, because STEs were explained by changes in attitudes toward the primary outgroup. This research speaks to equivocal findings in the extant STE literature and highlights directions for future research on social cohesion and bias reduction.

Beyond dark and bright: towards a more holistic understanding of inter-group networks.

Science.gov (United States)

Hejnova, Petra

2010-01-01

Networks are becoming a popular organizational form for structuring human activities. To date, scholars have addressed networks in a variety of fields, including sociology, economics, public administration, criminology, political science, and international security. However, little has been done so far to systematically examine the similarities, differences, and connections between network forms of organization across different academic disciplines. This has important implications for both theory and practice. The lack of attention paid to organizational similarities and differences prevents the exchange of knowledge developed across fields. In turn, policy-makers cannot take full advantage of existing research, and may miss opportunities to improve the work of some networks and combat that of others. To address this gap in the literature, this paper uses the combination of organizational environments and organizational goals to develop a new typology of inter-group networks, and thus improve our understanding of how human behaviour is coordinated through networks.

Preferences for religious education and inter-group attitudes among Indonesian students

NARCIS (Netherlands)

Sterkens, C.J.A.; Yusuf, M.

2015-01-01

This article analyses Indonesian students’ preferences for different types of religious education, with the help of their personal characteristics and inter-group attitudes. We investigate a comparative understanding of Muslim, Christian and Hindu students of different types of religious education.

Bridges or Barriers? Conceptualization of the Role of Multiple Identity Gateway Groups in Intergroup Relations

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Aharon Levy

2017-06-01

Full Text Available The modern era of globalization has been accompanied by a massive growth in interconnections between groups, and has led to the sharing of multiple identities by individuals and groups. Following these developments, research has focused on the issue of multiple identities, and has shed important light on how individuals who hold these complex forms of identity feel and behave, and on the reactions they elicit from members of other groups. However, the potential of groups with such multiple identities (e.g., biracials, immigrants, etc. to affect the intergroup relations between the groups that represent the respective sources of the different identities (e.g., Blacks and Whites, country of origin and country of residence, etc. has not been examined to date. Accordingly, in this paper, we first systematically explore the potential of groups in which people identify with multiple social categories, or groups that are perceived as such by others, to play a role in intergroup dynamics. Next, we offer a theoretical framework outlining what functions groups of people with shared multiple identities may serve (as bridges or barriers by proposing how their presence may facilitate or deteriorate intergroup relations. Finally, we present recent empirical research examining how groups of people with shared multiple identities can act as gateways and bridge the cleft between two separate groups that represent the respective sources of their different identities, and discuss the theoretical and practical implications for the field of intergroup relations.

Exact Analytic Result of Contact Value for the Density in a Modified Poisson-Boltzmann Theory of an Electrical Double Layer.

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Lou, Ping; Lee, Jin Yong

2009-04-14

For a simple modified Poisson-Boltzmann (SMPB) theory, taking into account the finite ionic size, we have derived the exact analytic expression for the contact values of the difference profile of the counterion and co-ion, as well as of the sum (density) and product profiles, near a charged planar electrode that is immersed in a binary symmetric electrolyte. In the zero ionic size or dilute limit, these contact values reduce to the contact values of the Poisson-Boltzmann (PB) theory. The analytic results of the SMPB theory, for the difference, sum, and product profiles were compared with the results of the Monte-Carlo (MC) simulations [ Bhuiyan, L. B.; Outhwaite, C. W.; Henderson, D. J. Electroanal. Chem. 2007, 607, 54 ; Bhuiyan, L. B.; Henderson, D. J. Chem. Phys. 2008, 128, 117101 ], as well as of the PB theory. In general, the analytic expression of the SMPB theory gives better agreement with the MC data than the PB theory does. For the difference profile, as the electrode charge increases, the result of the PB theory departs from the MC data, but the SMPB theory still reproduces the MC data quite well, which indicates the importance of including steric effects in modeling diffuse layer properties. As for the product profile, (i) it drops to zero as the electrode charge approaches infinity; (ii) the speed of the drop increases with the ionic size, and these behaviors are in contrast with the predictions of the PB theory, where the product is identically 1.

Modeling of contact theories for the manipulation of biological micro/nanoparticles in the form of circular crowned rollers based on the atomic force microscope

International Nuclear Information System (INIS)

Korayem, M. H.; Khaksar, H.; Taheri, M.

2013-01-01

This article has dealt with the development and modeling of various contact theories for biological nanoparticles shaped as cylinders and circular crowned rollers for application in the manipulation of different biological micro/nanoparticles based on Atomic Force Microscope. First, the effective contact forces were simulated, and their impact on contact mechanics simulation was investigated. In the next step, the Hertz contact model was simulated and compared for gold and DNA nanoparticles with the three types of spherical, cylindrical, and circular crowned roller type contact geometries. Then by reducing the length of the cylindrical section in the circular crowned roller geometry, the geometry of the body was made to approach that of a sphere, and the results were compared for DNA nanoparticles. To anticipatory validate the developed theories, the results of the cylindrical and the circular crowned roller contacts were compared with the results of the existing spherical contact simulations. Following the development of these contact models for the manipulation of various biological micro/nanoparticles, the cylindrical and the circular crowned roller type contact theories were modeled based on the theories of Lundberg, Dowson, Nikpur, Heoprich, and Hertz for the manipulation of biological micro/nanoparticles. Then, for a more accurate validation, the results obtained from the simulations were compared with those obtained by the finite element method and with the experimental results available in previous articles. The previous research works on the simulation of nanomanipulation have mainly investigated the contact theories used in the manipulation of spherical micro/nanoparticles. However since in real biomanipulation situations, biological micro/nanoparticles of more complex shapes need to be displaced in biological environments, this article therefore has modeled and compared, for the first time, different contact theories for use in the biomanipulation of

Overview of the InterGroup protocols

Energy Technology Data Exchange (ETDEWEB)

Berket, Karlo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Agarwal, Deborah A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Melliar-Smith, P. Michael [Univ. of California, Santa Barbara, CA (United States); Moser, Louise E. [Univ. of California, Santa Barbara, CA (United States)

2001-03-01

Existing reliable ordered group communication protocols have been developed for local-area networks and do not, in general, scale well to large numbers of nodes and wide-area networks. The InterGroup suite of protocols is a scalable group communication system that introduces a novel approach to handling group membership, and supports a receiver-oriented selection of service. The protocols are intended for a wide-area network, with a large number of nodes, that has highly variable delays and a high message loss rate, such as the Internet. The levels of the message delivery service range from unreliable unordered to reliable group timestamp ordered.

Threat and parochialism in intergroup relations: lab-in-the-field evidence from rural Georgia.

Science.gov (United States)

Schaub, Max

2017-10-25

Competition between groups is widely considered to foster cooperation within groups. Evidence from laboratory experiments hints at the existence of a proximate mechanism by which humans increase their level of cooperation with their ingroup when faced with an external threat. Further work suggests that ingroup cooperation should go along with aggressive behaviour towards the outgroup, although these theories are at odds with others that see high investments in outgroup relations as important means of stabilizing intergroup relations. Surprisingly, few of these arguments have been tested in the field, and existing studies are also limited by the lack of a direct measure of threat perception and aggressive behaviour. This study presents lab-in-the-field results from a rural context where exposure to an ethnic outgroup varies between villages. This context makes it possible to capture levels of threat perception, aggressive behaviour and cooperation without inducing intergroup competition artificially in the laboratory. All concepts are measured behaviourally. In- and outgroup cooperation was measured with a standard public goods game, and a novel experimental protocol was developed that measures perceived threat and aggressive behaviour: the threat game. The results show that levels of perceived threat, ingroup cooperation and aggressive behaviour are higher in regions more strongly exposed to ethnic outsiders. However, exposed regions also show high levels of outgroup cooperation and a concomitant lack of elevated ingroup bias. This pattern is explained by theorizing that communities show parochial altruism when faced with an ethnic outgroup, but balance aggressive behaviour with cooperative offers to diffuse tensions and to keep open channels of mutually beneficial exchange. © 2017 The Author(s).

Religion insulates ingroup evaluations : the development of intergroup attitudes in India

NARCIS (Netherlands)

Dunham, Yarrow; Srinivasan, Mahesh; Dotsch, Ron; Barner, David

Research on the development of implicit intergroup attitudes has placed heavy emphasis on race, leaving open how social categories that are prominent in other cultures might operate. We investigate two of India's primary means of social distinction, caste and religion, and explore the development of

Religion insulates ingroup evaluations: the development of intergroup attitudes in India

NARCIS (Netherlands)

Dunham, Y.; Srinivasan, M.; Dotsch, R.; Barner, D.

2014-01-01

Research on the development of implicit intergroup attitudes has placed heavy emphasis on race, leaving open how social categories that are prominent in other cultures might operate. We investigate two of India's primary means of social distinction, caste and religion, and explore the development of

Dehumanization, retributive and restorative justice, and aggressive versus diplomatic intergroup conflict resolution strategies.

Science.gov (United States)

Leidner, Bernhard; Castano, Emanuele; Ginges, Jeremy

2013-02-01

The desire for justice can escalate or facilitate resolution of intergroup conflicts. Two studies investigated retributive and restorative notions of justice as the mediating factor of the effect of perceived outgroup sentience-an aspect of (mechanistic) dehumanization referring to the emotional depth attributed to others-on intergroup conflict resolution. Study 1 showed that for Palestinians, who see themselves as victims, perceived sentience of Israelis decreased retributive but increased restorative notions of justice, which, ultimately, increased support for conflict resolution by negotiation rather than political violence. Study 2 partially replicated Study 1's findings with Jewish Israelis. The role of perceived sentience and its relationship to retributive and restorative notions of justice in protracted and nonprotracted conflicts and their resolution is discussed.

Large deformation contact mechanics of a pressurized long rectangular membrane. II. Adhesive contact

Science.gov (United States)

Srivastava, Abhishek; Hui, Chung-Yuen

2013-01-01

In part I of this work, we presented a theory for adhesionless contact of a pressurized neo-Hookean plane-strain membrane to a rigid substrate. Here, we extend our theory to include adhesion using a fracture mechanics approach. This theory is used to study contact hysteresis commonly observed in experiments. Detailed analysis is carried out to highlight the differences between frictionless and no-slip contact. Membrane detachment is found to be strongly dependent on adhesion: for low adhesion, the membrane ‘pinches-off’, whereas for large adhesions, it detaches unstably at finite contact (‘pull-off’). Expressions are derived for the critical adhesion needed for pinch-off to pull-off transition. Above a threshold adhesion, the membrane exhibits bistability, two stable states at zero applied pressure. The condition for bistability for both frictionless and no-slip boundary conditions is obtained explicitly. PMID:24353472

Children's intergroup helping: The role of empathy and peer group norms

NARCIS (Netherlands)

Sierksma, Jellie; Thijs, Jochem; Verkuijten, Maykel

2014-01-01

Two studies examined children's (8- to 13-year-olds) intergroup helping intentions. In Study 1, 856 children indicated their intention to help national in-group or out-group peers in a high need situation and in either a public or private context. Results showed that children's empathic tendencies

Group Representations and Intergroup Bias: Positive Affect, Similarity, and Group Size.

Science.gov (United States)

Dovidio, John F.; And Others

1995-01-01

Examined how social appearance and affective factors can influence social categorization and intergroup bias. Positive affect increased the extent to which subjects formed inclusive group representations, anticipating that the members of two groups would feel like one. Subjects in dissimilarly dressed groups expected the members to feel less like…

Affective dimensions of intergroup humiliation.

Directory of Open Access Journals (Sweden)

Bernhard Leidner

Full Text Available Despite the wealth of theoretical claims about the emotion of humiliation and its effect on human relations, there has been a lack of empirical research investigating what it means to experience humiliation. We studied the affective characteristics of humiliation, comparing the emotional experience of intergroup humiliation to two other emotions humiliation is often confused with: anger and shame. The defining characteristics of humiliation were low levels of guilt and high levels of other-directed outrage (like anger and unlike shame, and high levels of powerlessness (like shame and unlike anger. Reasons for the similarities and differences of humiliation with anger and shame are discussed in terms of perceptions of undeserved treatment and injustice. Implications for understanding the behavioral consequences of humiliation and future work investigating the role of humiliation in social life are discussed.

On the contact values of the density profiles in an electric double layer using density functional theory

Directory of Open Access Journals (Sweden)

L.B. Bhuiyan

2012-06-01

Full Text Available A recently proposed, local second contact value theorem [Henderson D., Boda D., J. Electroanal. Chem., 2005, Vol. 582, 16] for the charge profile of an electric double layer is used in conjunction with existing Monte Carlo data from the literature to assess the contact behavior of the electrode-ion distributions predicted by the density functional theory. The results for the contact values of the co- and counterion distributions and their product are obtained for the symmetric valency, restricted primitive model planar double layer for a range of electrolyte concentrations and temperatures. Overall the theoretical results satisfy the second contact value theorem reasonably well the agreement with the simulations being semi-quantitative or better. The product of the co- and counterion contact values as a function of the electrode surface charge density is qualitative with the simulations with increasing deviations at higher concentrations.

Obtaining macroscopic quantities for the contact line problem from Density Functional Theory using asymptotic methods

Science.gov (United States)

Sibley, David; Nold, Andreas; Kalliadasis, Serafim

2015-11-01

Density Functional Theory (DFT), a statistical mechanics of fluids approach, captures microscopic details of the fluid density structure in the vicinity of contact lines, as seen in computations in our recent study. Contact lines describe the location where interfaces between two fluids meet solid substrates, and have stimulated a wealth of research due to both their ubiquity in nature and technological applications and also due to their rich multiscale behaviour. Whilst progress can be made computationally to capture the microscopic to mesoscopic structure from DFT, complete analytical results to fully bridge to the macroscale are lacking. In this work, we describe our efforts to bring asymptotic methods to DFT to obtain results for contact angles and other macroscopic quantities in various parameter regimes. We acknowledge financial support from European Research Council via Advanced Grant No. 247031.

Disappointment expression evokes collective guilt and collective action in intergroup conflict: the moderating role of legitimacy perceptions.

Science.gov (United States)

Solak, Nevin; Reifen Tagar, Michal; Cohen-Chen, Smadar; Saguy, Tamar; Halperin, Eran

2017-09-01

Research on intergroup emotions has largely focused on the experience of emotions and surprisingly little attention has been given to the expression of emotions. Drawing on the social-functional approach to emotions, we argue that in the context of intergroup conflicts, outgroup members' expression of disappointment with one's ingroup induces the complementary emotion of collective guilt and correspondingly a collective action protesting ingroup actions against the outgroup. In Study 1 conducted immediately after the 2014 Gaza war, Jewish-Israeli participants received information about outgroup's (Palestinians) expression of emotions (disappointment, fear, or none). As predicted, outgroup's expression of disappointment increased collective guilt and willingness to participate in collective action, but only among those who saw the intergroup situation as illegitimate. Moreover, collective guilt mediated the relationship between disappointment expression and collective action, moderated, again, by legitimacy perception. In Study 2, we replicated these results in the context of racial tension between Black and White Americans in the US. We discuss the theoretical and applied implications of the findings.

Inter-group conflict and cooperation: field experiments before, during and after sectarian riots in Northern Ireland

Directory of Open Access Journals (Sweden)

Antonio S Silva

2015-11-01

Full Text Available The idea that cooperative groups out-compete less cooperative groups has been proposed as a theoretical possibility for the evolution of cooperation through cultural group selection. Previous studies have found an association between increased cooperation and exposure to inter-group violence, but most have not been able to identify the specific target of cooperation and are based on correlational data making it difficult to establish causality. In this study we test the hypothesis that inter-group conflict promotes parochial altruism (i.e. in-group altruism and out-group hostility by using longitudinal data of a real-world measure of cooperation – charity and school donations – sampled before, during and after violent sectarian riots between Catholics and Protestants in Belfast, Northern Ireland. We find that conflict is associated with reductions in all types of cooperation, with reduced donations to a neutral charity, and both in-group and out-group primary schools. After the conflict, both in-group and out-group donations increased again. In this context we find no evidence that inter-group conflict promotes parochial altruism.

Shared Features of L2 Writing: Intergroup Homogeneity and Text Classification

Science.gov (United States)

Crossley, Scott A.; McNamara, Danielle S.

2011-01-01

This study investigates intergroup homogeneity within high intermediate and advanced L2 writers of English from Czech, Finnish, German, and Spanish first language backgrounds. A variety of linguistic features related to lexical sophistication, syntactic complexity, and cohesion were used to compare texts written by L1 speakers of English to L2…

Intergroup jealousy: Effects of perceived group characteristics and intrasexual competition between groups.

NARCIS (Netherlands)

Klavina, Liga; Buunk, A.P.; Park, Justin; Høgh-Olesen, Hendrik; Tønnesvang, Jan; Bertelsen, Preben

2009-01-01

An important aspect of intergroup conflict is competition for mates, especially among men. Because different outgroups pose different levels of threat, the group membership of rivals can be a characteristic that evokes jealousy. Outgroups perceived to pose greater threat to one’s mating resources

Measuring intergroup ideologies: positive and negative aspects of emphasizing versus looking beyond group differences.

Science.gov (United States)

Hahn, Adam; Banchefsky, Sarah; Park, Bernadette; Judd, Charles M

2015-12-01

Research on interethnic relations has focused on two ideologies, asking whether it is best to de-emphasize social-category differences (colorblind) or emphasize and celebrate differences (multicultural). We argue each of these can manifest with negative outgroup evaluations: Assimilationism demands that subordinate groups adopt dominant group norms to minimize group distinctions; segregationism holds that groups should occupy separate spheres. Parallel versions can be identified for intergender relations. Scales to measure all four ideologies are developed both for ethnicity (Studies 1 and 2) and gender (Studies 3 and 4). Results demonstrate that the ideologies can be reliably measured, that the hypothesized four-factor models are superior to alternative models with fewer factors, and that the ideologies relate as predicted to the importance ascribed to group distinctions, subordinate group evaluations, and solution preferences for intergroup conflict scenarios. We argue that this fourfold model can help clarify theory and measurement, allowing a more nuanced assessment of ideological attitudes. © 2015 by the Society for Personality and Social Psychology, Inc.

“Ingroup love” and “outgroup hate” in intergroup conflict between natural groups

Science.gov (United States)

Weisel, Ori; Böhm, Robert

2015-01-01

We report on two studies investigating the motivations (“ingroup love” and “outgroup hate”) underlying individual participation in intergroup conflict between natural groups (fans of football clubs, supporters of political parties), by employing the Intergroup Prisoner's Dilemma Maximizing-Difference (IPD-MD) game. In this game group members can contribute to the ingroup (at a personal cost) and benefit ingroup members with or without harming members of an outgroup. Additionally, we devised a novel version of the IPD-MD in which the choice is between benefiting ingroup members with or without helping members of the outgroup. Our results show an overall reluctance to display outgroup hate by actively harming outgroup members, except when the outgroup was morality-based. More enmity between groups induced more outgroup hate only when it was operationalized as refraining from help. PMID:26339099

How intergroup friendship works: a longitudinal study of friendship effects on outgroup attitudes

NARCIS (Netherlands)

Turner, R.N.; Feddes, A.R.

2011-01-01

Cross-sectional research has shown that frequency of self-disclosure to outgroup members mediates the positive relationship between intergroup friendship and outgroup attitudes. The current research investigated the relationship between self-disclosure and attitudes in more depth. New undergraduate

Ethnic Identity Development and Acculturation Preferences Among Minority and Majority Youth: Norms and Contact.

Science.gov (United States)

González, Roberto; Lickel, Brian; Gupta, Manisha; Tropp, Linda R; Luengo Kanacri, Bernadette P; Mora, Eduardo; De Tezanos-Pinto, Pablo; Berger, Christian; Valdenegro, Daniel; Cayul, Oscar; Miranda, Daniel; Saavedra, Patricio; Bernardino, Michelle

2017-05-01

This article tests a longitudinal model of the antecedents and consequences of changes in identification with indigenous (Mapuche) among indigenous and nonindigenous youth in Chilean school contexts over a 6-month period (633 nonindigenous and 270 Mapuche students, M ages  = 12.47 and 12.80 years, respectively). Results revealed that in-group norms supporting contact and quality of intergroup contact at Time 1 predicted student's changes in Mapuche identification at Time 2, which in turn predicted changes in support for adoption of Chilean culture and maintenance of Mapuche culture at Time 2; some of the relationships between these variables were found to be moderated by age and ethnicity. Conceptual and policy implications are addressed in the Discussion. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

An elastic-plastic contact model for line contact structures

Science.gov (United States)

Zhu, Haibin; Zhao, Yingtao; He, Zhifeng; Zhang, Ruinan; Ma, Shaopeng

2018-06-01

Although numerical simulation tools are now very powerful, the development of analytical models is very important for the prediction of the mechanical behaviour of line contact structures for deeply understanding contact problems and engineering applications. For the line contact structures widely used in the engineering field, few analytical models are available for predicting the mechanical behaviour when the structures deform plastically, as the classic Hertz's theory would be invalid. Thus, the present study proposed an elastic-plastic model for line contact structures based on the understanding of the yield mechanism. A mathematical expression describing the global relationship between load history and contact width evolution of line contact structures was obtained. The proposed model was verified through an actual line contact test and a corresponding numerical simulation. The results confirmed that this model can be used to accurately predict the elastic-plastic mechanical behaviour of a line contact structure.

Impact of contact on adolescents’ mental health literacy and stigma: the SchoolSpace cluster randomised controlled trial

Science.gov (United States)

Chisholm, Katharine; Patterson, Paul; Torgerson, Carole; Turner, Erin; Jenkinson, David; Birchwood, Max

2016-01-01

Objectives To investigate whether intergroup contact in addition to education is more effective than education alone in reducing stigma of mental illness in adolescents. Design A pragmatic cluster randomised controlled trial compared education alone with education plus contact. Blocking was used to randomly stratify classes within schools to condition. Random allocation was concealed, generated by a computer algorithm, and undertaken after pretest. Data was collected at pretest and 2-week follow-up. Analyses use an intention-to-treat basis. Setting Secondary schools in Birmingham, UK. Participants The parents and guardians of all students in year 8 (age 12–13 years) were approached to take part. Interventions A 1-day educational programme in each school led by mental health professional staff. Students in the ‘contact’ condition received an interactive session with a young person with lived experience of mental illness. Outcomes The primary outcome was students’ attitudinal stigma of mental illness. Secondary outcomes included knowledge-based stigma, mental health literacy, emotional well-being and resilience, and help-seeking attitudes. Results Participants were recruited between 1 May 2011 and 30 April 2012. 769 participants completed the pretest and were randomised to condition. 657 (85%) provided follow-up data. At 2-week follow-up, attitudinal stigma improved in both conditions with no significant effect of condition (95% CI −0.40 to 0.22, p=0.5, d=0.01). Significant improvements were found in the education-alone condition compared with the contact and education condition for the secondary outcomes of knowledge-based stigma, mental health literacy, emotional well-being and resilience, and help-seeking attitudes. Conclusions Contact was found to reduce the impact of the intervention for a number of outcomes. Caution is advised before employing intergroup contact with younger student age groups. The education intervention appeared to be successful in

Factors Related to Initiating Interpersonal Contacts on Internet Dating Sites: A View From the Social Exchange Theory

Directory of Open Access Journals (Sweden)

Rivka Shtatfeld

2009-12-01

Full Text Available The purpose of this study was to identify factors that influence dating-site users to initiate contact with potential romantic partners. The study was carried out by observing online behaviors and analyzing the profiles and authentic messages of these users (N = 106 over seven months. Contacts made by and with the research participants were analyzed in terms of the relationships between initiators‘ and receivers‘ demographic variables (marital status, age, level of education, income, writing skills, and stated physical appearance. In addition, the relationship between contacting partners and site accessibility was examined. The findings revealed that dating-site users initiated contact primarily with those having a similar marital status or slightly better characteristics (income, education, writing skills. In regard to writing skills, it was found that skilled writers attracted more contacts than did less skilled writers. However, the factor that was found to be most significantly related to initiating contact was the length of time that elapsed from last connection to the site, which implies the perceived accessibility of potential romantic partners. The findings were explained in terms of the Social Exchange Theory: people are attracted to those who grant them rewards.

Opposing effects of personal and collective self-esteem on interpersonal and intergroup comparisons

NARCIS (Netherlands)

Long, KM; Spears, R

1998-01-01

The relationship between self-esteem deriving from both personal and social identity and comparisons at both interpersonal and intergroup level was examined. Participants took part in individual and group brainstorming tasks which they later had the opportunity to evaluate. In the case of the

A thermodynamic model of contact angle hysteresis.

Science.gov (United States)

Makkonen, Lasse

2017-08-14

When a three-phase contact line moves along a solid surface, the contact angle no longer corresponds to the static equilibrium angle but is larger when the liquid is advancing and smaller when the liquid is receding. The difference between the advancing and receding contact angles, i.e., the contact angle hysteresis, is of paramount importance in wetting and capillarity. For example, it determines the magnitude of the external force that is required to make a drop slide on a solid surface. Until now, fundamental origin of the contact angle hysteresis has been controversial. Here, this origin is revealed and a quantitative theory is derived. The theory is corroborated by the available experimental data for a large number of solid-liquid combinations. The theory is applied in modelling the contact angle hysteresis on a textured surface, and these results are also in quantitative agreement with the experimental data.

Quantum mechanical theory of positron production in heavy ion collisions with nuclear contact

International Nuclear Information System (INIS)

Heinz, U.

1986-01-01

The interplay between atomic and nuclear interactions in heavy ion collisions with nuclear contact is studied. The general theoretical description is outlined and analyzed in a number of different limits (semiclassical approximation, DWBA, fully quantal description). The two most important physical mechanisms for generating atomic-nuclear interference, i.e., energy conservation and the introduction of additional phase shifts by nuclear reactions, are extracted. The resulting typical coupling matrix elements are analyzed for their relative importance in atomic and nuclear excitations. The description of nuclear influence on atomic excitations in terms of a classical time delay caused by nuclear reactions is reviewed, and its relationship to the underlying quantal character of the nuclear reaction is discussed. The theory is applied to spontaneous positron emission in supercritical heavy-ion collisions (Z/sub tot/ ≥ 173). It is shown that nuclear contact can lead to line structures in the positron energy spectra if the probability distribution for nuclear delay times caused by the contact has contributions for T ≥ 10 -19 sec. We explicitly evaluate a model where a pocket in the internuclear potential near the touching configuration leads to formation of nuclear molecules, and predict a resonance-like excitation function for the positron peak. 25 refs., 7 figs

Impact of contact on adolescents' mental health literacy and stigma: the SchoolSpace cluster randomised controlled trial.

Science.gov (United States)

Chisholm, Katharine; Patterson, Paul; Torgerson, Carole; Turner, Erin; Jenkinson, David; Birchwood, Max

2016-02-19

To investigate whether intergroup contact in addition to education is more effective than education alone in reducing stigma of mental illness in adolescents. A pragmatic cluster randomised controlled trial compared education alone with education plus contact. Blocking was used to randomly stratify classes within schools to condition. Random allocation was concealed, generated by a computer algorithm, and undertaken after pretest. Data was collected at pretest and 2-week follow-up. Analyses use an intention-to-treat basis. Secondary schools in Birmingham, UK. The parents and guardians of all students in year 8 (age 12-13 years) were approached to take part. A 1-day educational programme in each school led by mental health professional staff. Students in the 'contact' condition received an interactive session with a young person with lived experience of mental illness. The primary outcome was students' attitudinal stigma of mental illness. Secondary outcomes included knowledge-based stigma, mental health literacy, emotional well-being and resilience, and help-seeking attitudes. Participants were recruited between 1 May 2011 and 30 April 2012. 769 participants completed the pretest and were randomised to condition. 657 (85%) provided follow-up data. At 2-week follow-up, attitudinal stigma improved in both conditions with no significant effect of condition (95% CI -0.40 to 0.22, p=0.5, d=0.01). Significant improvements were found in the education-alone condition compared with the contact and education condition for the secondary outcomes of knowledge-based stigma, mental health literacy, emotional well-being and resilience, and help-seeking attitudes. Contact was found to reduce the impact of the intervention for a number of outcomes. Caution is advised before employing intergroup contact with younger student age groups. The education intervention appeared to be successful in reducing stigma, promoting mental health knowledge, and increasing mental health literacy, as

Shared reality in intergroup communication: Increasing the epistemic authority of an out-group audience.

Science.gov (United States)

Echterhoff, Gerald; Kopietz, René; Higgins, E Tory

2017-06-01

Communicators typically tune messages to their audience's attitude. Such audience tuning biases communicators' memory for the topic toward the audience's attitude to the extent that they create a shared reality with the audience. To investigate shared reality in intergroup communication, we first established that a reduced memory bias after tuning messages to an out-group (vs. in-group) audience is a subtle index of communicators' denial of shared reality to that out-group audience (Experiments 1a and 1b). We then examined whether the audience-tuning memory bias might emerge when the out-group audience's epistemic authority is enhanced, either by increasing epistemic expertise concerning the communication topic or by creating epistemic consensus among members of a multiperson out-group audience. In Experiment 2, when Germans communicated to a Turkish audience with an attitude about a Turkish (vs. German) target, the audience-tuning memory bias appeared. In Experiment 3, when the audience of German communicators consisted of 3 Turks who all held the same attitude toward the target, the memory bias again appeared. The association between message valence and memory valence was consistently higher when the audience's epistemic authority was high (vs. low). An integrative analysis across all studies also suggested that the memory bias increases with increasing strength of epistemic inputs (epistemic expertise, epistemic consensus, and audience-tuned message production). The findings suggest novel ways of overcoming intergroup biases in intergroup relations. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Electrical contacts principles and applications

CERN Document Server

Slade, Paul G

2013-01-01

Covering the theory, application, and testing of contact materials, Electrical Contacts: Principles and Applications, Second Edition introduces a thorough discussion on making electric contact and contact interface conduction; presents a general outline of, and measurement techniques for, important corrosion mechanisms; considers the results of contact wear when plug-in connections are made and broken; investigates the effect of thin noble metal plating on electronic connections; and relates crucial considerations for making high- and low-power contact joints. It examines contact use in switch

Testosterone is associated with cooperation during intergroup competition by enhancing parochial altruism

Directory of Open Access Journals (Sweden)

Luise eReimers

2015-06-01

Full Text Available The steroid hormone testosterone is widely associated with negative behavioral effects, such as aggression or dominance. However, recent studies applying economic exchange tasks revealed conflicting results. While some point to a prosocial effect of testosterone by increasing altruistic behavior, others report that testosterone promotes antisocial tendencies. Taking into account additional factors such as parochial altruism (i.e., ingroup favoritism and outgroup hostility might help to explain this contradiction. First evidence for a link between testosterone and parochial altruism comes from recently reported data of male soccer fans playing the ultimatum game. In this study high levels of endogenous testosterone predicted increased altruistic punishment during outgroup interactions and at the same time heightened ingroup generosity. Here, we report findings of another experimental task, the prisoner’s dilemma, applied in the same context to examine the role of testosterone on parochial tendencies in terms of cooperation. In this task, fifty male soccer fans were asked to decide whether or not they wanted to cooperate with partners marked as either fans of the subject’s own favorite team (ingroup or fans of other teams (outgroups. Our results show that high testosterone levels were associated with increased ingroup cooperation during intergroup competition. In addition, subjects displaying a high degree of parochialism during intergroup competition had significantly higher levels of testosterone than subjects who did not differentiate much between the different groups. In sum, the present data demonstrate that the behavioral effects of testosterone are not limited to aggressive and selfish tendencies but may imply prosocial aspects depending on the context. By this means, our results support the previously reported findings on testosterone-dependent intergroup bias and indicate that this social hormone might be an important factor driving

Testosterone is associated with cooperation during intergroup competition by enhancing parochial altruism.

Science.gov (United States)

Reimers, Luise; Diekhof, Esther K

2015-01-01

The steroid hormone testosterone is widely associated with negative behavioral effects, such as aggression or dominance. However, recent studies applying economic exchange tasks revealed conflicting results. While some point to a prosocial effect of testosterone by increasing altruistic behavior, others report that testosterone promotes antisocial tendencies. Taking into account additional factors such as parochial altruism (i.e., ingroup favoritism and outgroup hostility) might help to explain this contradiction. First evidence for a link between testosterone and parochial altruism comes from recently reported data of male soccer fans playing the ultimatum game. In this study high levels of endogenous testosterone predicted increased altruistic punishment during outgroup interactions and at the same time heightened ingroup generosity. Here, we report findings of another experimental task, the prisoner's dilemma, applied in the same context to examine the role of testosterone on parochial tendencies in terms of cooperation. In this task, 50 male soccer fans were asked to decide whether or not they wanted to cooperate with partners marked as either fans of the subject's own favorite team (ingroup) or fans of other teams (outgroups). Our results show that high testosterone levels were associated with increased ingroup cooperation during intergroup competition. In addition, subjects displaying a high degree of parochialism during intergroup competition had significantly higher levels of testosterone than subjects who did not differentiate much between the different groups. In sum, the present data demonstrate that the behavioral effects of testosterone are not limited to aggressive and selfish tendencies but may imply prosocial aspects depending on the context. By this means, our results support the previously reported findings on testosterone-dependent intergroup bias and indicate that this social hormone might be an important factor driving parochial altruism.

A survey of wheel-rail contact models for rail vehicles

Science.gov (United States)

Meymand, Sajjad Z.; Keylin, Alexander; Ahmadian, Mehdi

2016-03-01

Accurate and efficient contact models for wheel-rail interaction are essential for the study of the dynamic behaviour of a railway vehicle. Assessment of the contact forces and moments, as well as contact geometry provide a fundamental foundation for such tasks as design of braking and traction control systems, prediction of wheel and rail wear, and evaluation of ride safety and comfort. This paper discusses the evolution and the current state of the theories for solving the wheel-rail contact problem for rolling stock. The well-known theories for modelling both normal contact (Hertzian and non-Hertzian) and tangential contact (Kalker's linear theory, FASTSIM, CONTACT, Polach's theory, etc.) are reviewed. The paper discusses the simplifying assumptions for developing these models and compares their functionality. The experimental studies for evaluation of contact models are also reviewed. This paper concludes with discussing open areas in contact mechanics that require further research for developing better models to represent the wheel-rail interaction.

Trade and inter-group relations in the lower Niger 1830-1960 | Ali ...

African Journals Online (AJOL)

This study focuses on trade and intergroup relations in the Lower Niger in the period 1830-1960. Trade constitutes an integral aspect of communal relationship in the Lower Niger region from 1830 to 1960. The objective of the study is to show how the people of the Lower Niger related with each other in trade and other ...

The Role of Social Identity Complexity in Inter-Group Attitudes among Young Adolescents

Science.gov (United States)

Knifsend, Casey A.; Juvonen, Jaana

2013-01-01

To supplement research on adolescent social identities, the current study examined how social identity complexity relates to ethnic inter-group attitudes in a young adolescent sample (N = 97; "age range" = 12-14 years). Social identity complexity refers to the perceived overlap of groups with which youth align themselves. Descriptive…

Social Identity Complexity, Cross-Ethnic Friendships, and Intergroup Attitudes in Urban Middle Schools

Science.gov (United States)

Knifsend, Casey A.; Juvonen, Jaana

2014-01-01

This study investigated contextual antecedents (i.e., cross-ethnic peers and friends) and correlates (i.e., intergroup attitudes) of social identity complexity in seventh grade. Social identity complexity refers to the perceived overlap among social groups with which youth identify. Identifying mostly with out-of-school sports, religious…

Friction and universal contact area law for randomly rough viscoelastic contacts.

Science.gov (United States)

Scaraggi, M; Persson, B N J

2015-03-18

We present accurate numerical results for the friction force and the contact area for a viscoelastic solid (rubber) in sliding contact with hard, randomly rough substrates. The rough surfaces are self-affine fractal with roughness over several decades in length scales. We calculate the contribution to the friction from the pulsating deformations induced by the substrate asperities. We also calculate how the area of real contact, A(v, p), depends on the sliding speed v and on the nominal contact pressure p, and we show how the contact area for any sliding speed can be obtained from a universal master curve A(p). The numerical results are found to be in good agreement with the predictions of an analytical contact mechanics theory.

El efecto de la amenaza intergrupal y la identidad social saliente en la creencia en teorías de conspiración sobre el terrorismo en Indonesia: la angustia colectiva como un mediador

OpenAIRE

Mashuri, Ali; Zaduqisti, Esti

2015-01-01

The present study tested how intergroup threat (high versus low) and social identity as a Muslim (salient versus non-salient) affected belief in conspiracy theories. Data among Indonesian Muslim students (N = 139) from this study demonstrated that intergroup threat and social identity salience interacted to influence belief in conspiracy theories. High intergroup threat triggered greater belief in conspiracy theories than low intergroup threat, more prominently in the condition in which parti...

International support for the Arab Uprisings: Understanding sympathy protests using theories of social identity and social dominance

NARCIS (Netherlands)

Stewart, A.L.; Pratto, F.; Bou Zeineddine, F.; Sweetman, J.; Eicher, V.; Licata, L.; Morselli, D.; Saab, R.; Aiello, A.; Chryssochoou, X.; Cichocka, A.; Cidam, A.; Foels, R.; Giguére, B.; Li, L.; Prati, F.; van Stekelenburg, J.

2016-01-01

Inspired by the popular Arab protests against oppressive regimes that began in 2010, people around the world protested in sympathy with the Arab peoples. The present research draws on two major theories of intergroup relations to develop an initial integrative model of sympathetic collective action.

Advantaged group's emotional reactions to intergroup inequality: the dynamics of pride, guilt, and sympathy.

Science.gov (United States)

Harth, Nicole Syringa; Kessler, Thomas; Leach, Colin Wayne

2008-01-01

Three studies establish intergroup inequality to investigate how it is emotionally experienced by the advantaged. Studies 1 and 2 examine psychology students' emotional experience of their unequal job situation with worse-off pedagogy students. When inequality is ingroup focused and legitimate, participants experience more pride. However, when inequality is ingroup focused and illegitimate, participants experience more guilt. Sympathy is increased when inequality is outgroup focused and illegitimate. These emotions have particular effects on behavioral tendencies. In Study 2 group-based pride predicts greater ingroup favoritism in a resource distribution task, whereas group-based sympathy predicts less ingroup favoritism. Study 3 replicates these findings in the context of students' willingness to let young immigrants take part in a university sport. Pride predicts less willingness to let immigrants take part whereas sympathy predicts greater willingness. Guilt is a weak predictor of behavioral tendencies in all studies. This shows the specificity of emotions experienced about intergroup inequality.

A Closer Look at Intergroup Threat Within the Dual Process Model Framework: The Mediating Role of Moral Foundations

Directory of Open Access Journals (Sweden)

Márton Hadarics

2017-04-01

Full Text Available In our study we investigated how right-wing authoritarianism (RWA and social dominance orientation (SDO are related to perceived intergroup threat, and also tested the potential mediating role of individualizing and binding moral foundations within this relationship pattern. According to our results, both RWA and SDO enhanced the perceived threat related to immigration. Furthermore, the effect of SDO was partly mediated by individualizing moral foundations, while the effect of RWA was partly mediated by both kinds of moral foundations. It seems that perceived intergroup threat, at least to some extent, is influenced by personal moral preferences that can be derived from individual dispositions and motivations.

Conceptualizing intragroup and intergroup dynamics within a controlled crowd evacuation.

Science.gov (United States)

Elzie, Terra; Frydenlund, Erika; Collins, Andrew J; Robinson, R Michael

2015-01-01

Social dynamics play a critical role in successful pedestrian evacuations. Crowd modeling research has made progress in capturing the way individual and group dynamics affect evacuations; however, few studies have simultaneously examined how individuals and groups interact with one another during egress. To address this gap, the researchers present a conceptual agent-based model (ABM) designed to study the ways in which autonomous, heterogeneous, decision-making individuals negotiate intragroup and intergroup behavior while exiting a large venue. A key feature of this proposed model is the examination of the dynamics among and between various groupings, where heterogeneity at the individual level dynamically affects group behavior and subsequently group/group interactions. ABM provides a means of representing the important social factors that affect decision making among diverse social groups. Expanding on the 2013 work of Vizzari et al., the researchers focus specifically on social factors and decision making at the individual/group and group/group levels to more realistically portray dynamic crowd systems during a pedestrian evacuation. By developing a model with individual, intragroup, and intergroup interactions, the ABM provides a more representative approximation of real-world crowd egress. The simulation will enable more informed planning by disaster managers, emergency planners, and other decision makers. This pedestrian behavioral concept is one piece of a larger simulation model. Future research will build toward an integrated model capturing decision-making interactions between pedestrians and vehicles that affect evacuation outcomes.

Superstring amplitudes and contact interactions

International Nuclear Information System (INIS)

Greensite, J.

1987-08-01

We show that scattering amplitudes computed from light-cone superstring field theory are divergent at tree level. The divergences can be eliminated, and supersymmetry restored, by the addition of certain counter terms to the light-cone Hamiltonian. These counter terms have the form of local contact interactions, whose existence we had previously deduced on grounds of vacuum stability, and closure of the super-Poincare algebra. The quartic contact interactions required in Type I and Type IIB superstring theories are constructed in detail. (orig.)

Practice patterns of radiotherapy in endometrial cancer among member groups of the gynecologic cancer intergroup

DEFF Research Database (Denmark)

Small, W.Jr.; Bois, A. Du; Bhatnagar, S.

2009-01-01

PURPOSE: To describe radiotherapeutic practice of the treatment of endometrial cancer in members of the Gynecologic Cancer Intergroup (GCIG). METHODS: A survey was developed and distributed to the members of the GCIG. The GCIG is a global association of cooperative groups involved in the research.......57 [10.13] Gy in a mean of 4.3 insertions), and 5 groups used low-dose-rate brachytherapy (41.45 [17.5] Gy). Nineteen of the 28 respondents measured the doses to the bladder and the rectum when performing VBT. For brachytherapy, there was no uniformity in the fraction of the vagina treated or the doses...... and schedules used. CONCLUSIONS: Radiotherapy practices among member groups of the GCIG are similar in doses and dose per fraction with external beam. There is a moderate discrepancy in the brachytherapy practice after hysterectomy. There are no serious impediments to intergroup participation in radiation...

Listen to the band! How sound can realize group identity and enact intergroup domination.

Science.gov (United States)

Shayegh, John; Drury, John; Stevenson, Clifford

2017-03-01

Recent research suggests that sound appraisal can be moderated by social identity. We validate this finding, and also extend it, by examining the extent to which sound can also be understood as instrumental in intergroup relations. We interviewed nine members of a Catholic enclave in predominantly Protestant East Belfast about their experiences of an outgroup (Orange Order) parade, where intrusive sound was a feature. Participants reported experiencing the sounds as a manifestation of the Orange Order identity and said that it made them feel threatened and anxious because they felt it was targeted at them by the outgroup (e.g., through aggressive volume increases). There was also evidence that the sounds produced community disempowerment, which interviewees explicitly linked to the invasiveness of the music. Some interviewees described organizing to collectively 'drown out' the bands' sounds, an activity which appeared to be uplifting. These findings develop the elaborated social identity model of empowerment, by showing that intergroup struggle and collective self-objectification can operate through sound as well as through physical actions. © 2016 The British Psychological Society.

New developments in the theory of wheel/rail contact mechanics

DEFF Research Database (Denmark)

Nielsen, Jakob Birkedal

1998-01-01

Today many simulation routines concerning railway dynamics employ rather primitive contact models which are not necessarily suited for the specific wheel/rail contact problem. The objective of the present thesis is to derive a more flexible contact model which can be applied on a variety of conta...

Forces in Liquid Metal Contacts

DEFF Research Database (Denmark)

Duggen, Lars; Mátéfi-Tempfli, Stefan

2014-01-01

Using rather well known theory about capillary bridges between two electrodes we calculate the tensile force that can be applied to liquid metal contacts in the micrometer regime. Assuming circular symmetry, full wetting of the electrodes, and neglecting gravity, we present a brief review of the ...... of the necessary theory and find numerically the forces to be in the 100μN range for liquid metals as mercury and liquid Gallium suspended between electrodes of 20μm radius.......Using rather well known theory about capillary bridges between two electrodes we calculate the tensile force that can be applied to liquid metal contacts in the micrometer regime. Assuming circular symmetry, full wetting of the electrodes, and neglecting gravity, we present a brief review...

Contact isotopic- and contact ion-exchange between two adsorbents

International Nuclear Information System (INIS)

Bunzl, K.; Mohan, R.; Haimerl, M.

1975-01-01

The kinetics of contact ion exchange processes between an ion exchange membrane and resin ion exchange beads, stirred in pure water, was investigated. A general criterion was derived, which indicates whether diffusion of the ions between the intermingling electric double layers or the collision frequency between the two adsorbents is the rate dermining step. Since the latter process proved to be rate controlling under our experimental conditions, the corresponding rate equations were derived under various initial and boundary conditions. Experimentally, the kinetics of contact isotopic exchange of Cs + - and Na + -ions as well as of the reverse contact ion exchange process of Cs + -versus Na + -ions were investigated by using Na 22 and Cs 137 radioisotopes. The experiments reveal in quantitative accord with the theory that the rate of collision controlled contact ion exchange processes depends mainly on the 'exchange coefficient', the separation factor and the collision frequency. While the latter two quantities were determined independently by separate experiments, the 'exchange coefficient' was evaluated from a contact isotopic exchange experiment. (orig.) [de

Linguistic intergroup bias in political communication.

Science.gov (United States)

Anolli, Luigi; Zurloni, Valentino; Riva, Giuseppe

2006-07-01

The Linguistic Intergroup Bias (LIB) illustrates the disposition to communicate positive in-group and negative out-group behaviors more abstractly than negative in-group and positive out-group behaviors. The present research examined the function of language in reinforcing this bias in political communication. To illustrate the LIB, the Linguistic Category Model (LCM) was used, including a nouns category. Because social stereotypes are usually conveyed by nominal terms, the aim was to observe the relationship between stereotypes and language in political communication. Moreover, we were interested in analyzing the psychological processes that drive the LIB. Therefore, we verified whether the LIB is more related to language abstractness than to agent-patient causality. Several political debates and interviews, which took place before the latest Italian provincial elections, were analyzed. Results suggested that the language politicians use in communicating about political groups are conceptualized as stereotypes rather than as trait-based categories. Moreover, it seems that the LIB could not be explained only at a lexical level. Social implications of the present findings in interpersonal relations and causal attribution were discussed.

Frequency shift and hysteresis suppression in contact-mode AFM using contact stiffness modulation

Directory of Open Access Journals (Sweden)

Belhaq M.

2012-07-01

Full Text Available In this paper the frequency response shift and hysteresis suppression of contact-mode atomic force microscopy is investigated using parametric modulation of the contact stiffness. Based on the Hertzian contact theory, a lumped single degree of freedom oscillator is considered for modeling the cantilever dynamics contact-mode atomic force microscopy. We use the technique of direct partition of motion and the method of multiple scales to obtain, respectively, the slow dynamic and the corresponding slow flow of the system. As results, this study shows that the amplitude of the contact stiffness modulation has a significant effect on the frequency response. Specifically, increasing the amplitude of the stiffness modulation suppresses hysteresis, decreases the peak amplitude and produces shifts towards higher and lower frequencies.

Intergroup Contact, Attitudes toward Homosexuality, and the Role of Acceptance of Gender Non-Conformity in Young Adolescents

Science.gov (United States)

Collier, Kate L.; Bos, Henny M. W.; Sandfort, Theo G. M.

2012-01-01

This study explored how contact with gay and lesbian persons affects adolescents' attitudes toward them, and whether this association is mediated or moderated by one's acceptance of gender non-conformity. We analyzed survey responses from 456 Dutch adolescents aged 12-15 who reported having no same-sex attractions. Data were collected in 2008 at 8…

How we think they see us? Valence and difficulty of retrieval as moderators of the effect of meta-stereotype activation on intergroup orientations.

Science.gov (United States)

Vázquez, Alexandra; Yzerbyt, Vincent; Dovidio, John F; Gómez, Ángel

2017-12-01

Previous research indicates that meta-stereotypes are predominantly negative. However, the valence of the meta-stereotypes may not be the only factor accounting for the detrimental effects associated with their activation. In addition to valence, we propose that the subjective difficulty of retrieving the meta-stereotype might critically determine whether its activation deteriorates intergroup orientations. An experimental study showed that the effect of the meta-stereotype activation on the desire to interact with outgroup members was moderated by the interaction between the valence of the meta-stereotype and its difficulty of retrieval. In particular, the activation of a positive meta-stereotype deteriorated intergroup orientations when the difficulty of retrieval was high as compared with a condition in which the difficulty of retrieval was low. In sharp contrast, the activation of a negative meta-stereotype worsened intergroup orientations when the difficulty of retrieval was low as compared with a condition in which the difficulty of retrieval was high. © 2016 International Union of Psychological Science.

Group rationale, collective sense: beyond intergroup bias.

Science.gov (United States)

Spears, Russell

2010-03-01

In this paper, I contest the view of the group as a source of bias and irrationality, especially prevalent within social psychology. I argue that this negative evaluation often arises by applying inappropriate standards, relating to the wrong level of analysis (often the individual level). Second, the image of the group as bad and biasing is often overstated. For example, the evidence suggests that intergroup discrimination, rather than being universal or generic, is often constrained, proportionate and reflects functional and rational strategies for managing threats and opportunities at the group level. Third, although the recent upsurge of interest in group emotions could be seen to reinforce the dualism between rationality and emotion, the contemporary functional approach argues for group emotions as augmenting rather than contradicting rationality. However, we should be wary (and weary) of narrow economic and individualist notions of rationality; group identity may offer the opportunity to redefine rationality in more collective and prosocial ways.

Restoring the consistency with the contact density theorem of a classical density functional theory of ions at a planar electrical double layer.

Science.gov (United States)

Gillespie, Dirk

2014-11-01

Classical density functional theory (DFT) of fluids is a fast and efficient theory to compute the structure of the electrical double layer in the primitive model of ions where ions are modeled as charged, hard spheres in a background dielectric. While the hard-core repulsive component of this ion-ion interaction can be accurately computed using well-established DFTs, the electrostatic component is less accurate. Moreover, many electrostatic functionals fail to satisfy a basic theorem, the contact density theorem, that relates the bulk pressure, surface charge, and ion densities at their distances of closest approach for ions in equilibrium at a smooth, hard, planar wall. One popular electrostatic functional that fails to satisfy the contact density theorem is a perturbation approach developed by Kierlik and Rosinberg [Phys. Rev. A 44, 5025 (1991)PLRAAN1050-294710.1103/PhysRevA.44.5025] and Rosenfeld [J. Chem. Phys. 98, 8126 (1993)JCPSA60021-960610.1063/1.464569], where the full free-energy functional is Taylor-expanded around a bulk (homogeneous) reference fluid. Here, it is shown that this functional fails to satisfy the contact density theorem because it also fails to satisfy the known low-density limit. When the functional is corrected to satisfy this limit, a corrected bulk pressure is derived and it is shown that with this pressure both the contact density theorem and the Gibbs adsorption theorem are satisfied.

Athletes and Sedentary Individuals: An Intergroup Comparison Utilizing a Pulmonary Function Ratio Obtained During Submaximal Exercise.

Science.gov (United States)

Maud, Peter J.

A pulmonary function ratio describing oxygen extraction from alveolar ventilation was used for an intergroup comparison between three groups of athletes (rugby, basketball, and football players) and one group of sedentary subjects during steady-state submaximal exercise. The ratio and its component parts are determined from only three gas…

CFD simulation of direct contact condensation with ANSYS CFX using surface renewal theory based heat transfer coefficients

Energy Technology Data Exchange (ETDEWEB)

Wanninger, Andreas; Ceuca, Sabin Cristian; Macian-Juan, Rafael [Technische Univ. Muenchen, Garching (Germany). Dept. of Nuclear Engineering

2013-07-01

Different approaches for the calculation of Direct Contact Condensation (DCC) using Heat Transfer Coefficients (HTC) based on the Surface Renewal Theory (SRT) are tested using the CFD simulation tool ANSYS CFX. The present work constitutes a preliminary study of the flow patterns and conditions observed using different HTC models. A complex 3D flow pattern will be observed in the CFD simulations as well as a strong coupling between the condensation rate and the two-phase flow dynamics. (orig.)

Mean field theory of epidemic spreading with effective contacts on networks

International Nuclear Information System (INIS)

Wu, Qingchu; Chen, Shufang

2015-01-01

We present a general approach to the analysis of the susceptible-infected-susceptible model with effective contacts on networks, where each susceptible node will be infected with a certain probability only for effective contacts. In the network, each node has a given effective contact number. By using the one-vertex heterogenous mean-field (HMF) approximation and the pair HMF approximation, we obtain conditions for epidemic outbreak on degree-uncorrelated networks. Our results suggest that the epidemic threshold is closely related to the effective contact and its distribution. However, when the effective contact is only dependent of node degree, the epidemic threshold can be established by the degree distribution of networks.

Dynamic contact angle of water-based titanium oxide nanofluid

Science.gov (United States)

2013-01-01

This paper presents an investigation into spreading dynamics and dynamic contact angle of TiO2-deionized water nanofluids. Two mechanisms of energy dissipation, (1) contact line friction and (2) wedge film viscosity, govern the dynamics of contact line motion. The primary stage of spreading has the contact line friction as the dominant dissipative mechanism. At the secondary stage of spreading, the wedge film viscosity is the dominant dissipative mechanism. A theoretical model based on combination of molecular kinetic theory and hydrodynamic theory which incorporates non-Newtonian viscosity of solutions is used. The model agreement with experimental data is reasonable. Complex interparticle interactions, local pinning of the contact line, and variations in solid–liquid interfacial tension are attributed to errors. PMID:23759071

Facing the situation: Testing a biosocial contingency model of leadership in intergroup relations using masculine and feminine faces

NARCIS (Netherlands)

Spisak, B.R.; Homan, A.C.; Grabo, A.E.; van Vugt, M.

2012-01-01

Using an evolutionary psychology framework we propose that leadership and followership are evolved traits to solve recurrent group coordination problems. We argue that adaptive problems such as those concerning intergroup conflict or cooperation activate different cognitive leadership prototypes,

How cultural evolutionary theory can inform social psychology and vice versa.

Science.gov (United States)

Mesoudi, Alex

2009-10-01

Cultural evolutionary theory is an interdisciplinary field in which human culture is viewed as a Darwinian process of variation, competition, and inheritance, and the tools, methods, and theories developed by evolutionary biologists to study genetic evolution are adapted to study cultural change. It is argued here that an integration of the theories and findings of mainstream social psychology and of cultural evolutionary theory can be mutually beneficial. Social psychology provides cultural evolution with a set of empirically verified microevolutionary cultural processes, such as conformity, model-based biases, and content biases, that are responsible for specific patterns of cultural change. Cultural evolutionary theory provides social psychology with ultimate explanations for, and an understanding of the population-level consequences of, many social psychological phenomena, such as social learning, conformity, social comparison, and intergroup processes, as well as linking social psychology with other social science disciplines such as cultural anthropology, archaeology, and sociology.

Predicting guar seed splitting by compression between two plates using Hertz theory of contact stresses.

Science.gov (United States)

Vishwakarma, R K; Shivhare, U S; Nanda, S K

2012-09-01

Hertz's theory of contact stresses was applied to predict the splitting of guar seeds during uni-axial compressive loading between 2 rigid parallel plates. The apparent modulus of elasticity of guar seeds varied between 296.18 and 116.19 MPa when force was applied normal to hilum joint (horizontal position), whereas it varied between 171.86 and 54.18 MPa when force was applied in the direction of hilum joint (vertical position) with in moisture content range of 5.16% to 15.28% (d.b.). At higher moisture contents, the seeds yielded after considerable deformation, thus showing ductile nature. Distribution of stresses below the point of contact were plotted to predict the location of critical point, which was found at 0.44 to 0.64 mm and 0.37 to 0.53 mm below the contact point in vertical and horizontal loading, respectively, depending upon moisture content. The separation of cotyledons from each other initiated before yielding of cotyledons and thus splitting of seed took place. The relationships between apparent modulus of elasticity, principal stresses with moisture content were described using second-order polynomial equations and validated experimentally. Manufacture of guar gum powder requires dehulling and splitting of guar seeds. This article describes splitting behavior of guar seeds under compressive loading. Results of this study may be used for design of dehulling and splitting systems of guar seeds. © 2012 Institute of Food Technologists®

Interdependent Construal of Self and the Endorsement of Conflict Resolution Strategies in Interpersonal, Intergroup, and International Disputes.

Science.gov (United States)

Derlega, Valerian J.; Cukur, Cem Safak; Kuang, Jenny C. Y.; Forsyth, Donelson R.

2002-01-01

College students from countries with collectivistic and individualistic cultures completed a self-construal measure, then identified how they would respond to conflicts with another individual between their group and another group, or between their country and another country. Participants responded more negatively to intergroup and international…

Group Facial Width-to-Height Ratio Predicts Intergroup Negotiation Outcomes.

Science.gov (United States)

Yang, Yu; Tang, Chen; Qu, Xiaofei; Wang, Chao; Denson, Thomas F

2018-01-01

Past studies have found that the facial width-to-height ratio (FWHR) is associated with a range of traits and behaviors that are possibly important to dyadic negotiations. However, it is unknown whether the FWHR would have an impact on intergroup negotiations, which happen frequently and often have higher stakes in the real world. To examine this question, in the current study, we randomly assigned 1,337 Chinese business executives into 288 groups and they completed a multi-issue negotiation exercise against each other. Results showed that groups with larger maximum individual FWHRs achieved objectively better negotiation outcomes. We conclude that groups containing individuals with relatively large FWHRs can claim more value in negotiations between groups.

How Affectively-Based and Cognitively-Based Attitudes Drive Intergroup Behaviours: The Moderating Role of Affective-Cognitive Consistency

Science.gov (United States)

Zhou, Jie; Dovidio, John; Wang, Erping

2013-01-01

The moderating role of affective-cognitive consistency in the effects of affectively-based and cognitively-based attitudes on consummatory and instrumental behaviors was explored using two experimental studies in the intergroup context. Study 1 revealed that affectively-based attitudes were better predictors than cognitively-based attitudes regardless of affective-cognitive consistency for consummatory behaviors (e.g., undergraduates’ supportive behaviors toward government officials). Study 2, which investigated task groups’ supportive behaviors toward an immediate supervisory group, found that for these instrumental behaviors cognitively-based attitudes were better predictors than affectively-based attitudes only when affective-cognitive consistency was high. The present research also examined the mechanism by which affective-cognitive consistency moderates the relative roles of affectively-based and cognitively-based attitudes in attitude-behavior consistency. Results indicated that attitude-behavior consistency is eroded primarily because of the weaker relationship of affective or cognitive components to behaviors than to general attitudes. The reciprocal implications of research on attitudes and work on intergroup relations are considered. PMID:24244751

Feeling (Mis)Understood and Intergroup Friendships in Interracial Interactions.

Science.gov (United States)

Shelton, Nicole; Douglass, Sara; Garcia, Randi L; Yip, Tiffany; Trail, Thomas E

2014-09-01

The present research investigated whether having out-group friends serves as a buffer for feeling misunderstood in interracial interactions. Across three experience sampling studies, we found that among ethnic minorities who have few White friends or are not interacting with White friends, daily interracial interactions are associated with feeling less understood. By contrast, we found that among ethnic minorities who have more White friends or are interacting with White friends, the relationship between daily interracial interactions and feeling understood is not significant. We did not find similar results for Whites; that is, having ethnic minority friends did not play a role in the relationship between daily interracial interactions and feeling understood. Together, these studies demonstrate the beneficial effects of intergroup friendships for ethnic minorities. © 2014 by the Society for Personality and Social Psychology, Inc.

Experimental Validation of the Invariance of Electrowetting Contact Angle Saturation

NARCIS (Netherlands)

Chevalliot, S.; Dhindsa, M.; Kuiper, S.; Heikenfeld, J.

2011-01-01

Basic electrowetting theory predicts that a continued increase in applied voltage will allow contact angle modulation to zero degrees. In practice, the effect of contact angle saturation has always been observed to limit the contact angle modulation, often only down to a contact angle of 60 to 70°.

'We know them, but we don't know them': a grounded theory approach to exploring host students' perspectives on intercultural contact in an Irish university

OpenAIRE

Dunne, Ciaran

2008-01-01

This study is concerned with intercultural relations among students in an Irish university. Specifically, the study explores host culture students’ perceptions of cultural difference within the student body and their experiences of intercultural contact on campus, including the factors which inform such contact. Using a grounded theory approach, 24 in-depth qualitative interviews were conducted with 2nd year undergraduate students from three courses. The data were rigorously analysed thro...

Effect of Tabor parameter on hysteresis losses during adhesive contact

Science.gov (United States)

Ciavarella, M.; Greenwood, J. A.; Barber, J. R.

2017-01-01

The Tabor parameter μ is conventionally assumed to determine the range of applicability of the classical 'JKR' solution for adhesive elastic contact of a sphere and a plane, with the variation of the contact area and approach with load, and in particular the maximum tensile force (the pull-off force) being well predicted for μ > 5 . Here we show that the hysteretic energy loss during a contact separation cycle is significantly overestimated by the JKR theory, even at quite large values of μ. This stems from the absence of long-range tensile forces in the JKR theory, which implies that jump into contact is delayed until the separation α = 0 . We develop an approximate solution based on the use of Wu's solution with van der Waals interactions for jump-in, and the JKR theory for jump out of contact, and show that for μ > 5 , the predicted hysteresis loss is then close to that found by direct numerical solutions using the Lennard-Jones force law. We also show how the same method can be adapted to allow for contact between bodies with finite support stiffness.

Power and threat in intergroup conflict : How emotional and behavioral responses depend on amount and content of threat

NARCIS (Netherlands)

Kamans, Elanor; Otten, Sabine; Gordijn, Ernestine H.

We propose that in intergroup conflict threat content is important in understanding the reactions of those who experience threats the most: the powerless. Studies 1 and 2 show that powerless groups experience more threat than powerful groups, resulting in the experience of both more anger and fear.

Health beliefs affect the correct replacement of daily disposable contact lenses: Predicting compliance with the Health Belief Model and the Theory of Planned Behaviour.

Science.gov (United States)

Livi, Stefano; Zeri, Fabrizio; Baroni, Rossella

2017-02-01

To assess the compliance of Daily Disposable Contact Lenses (DDCLs) wearers with replacing lenses at a manufacturer-recommended replacement frequency. To evaluate the ability of two different Health Behavioural Theories (HBT), The Health Belief Model (HBM) and The Theory of Planned Behaviour (TPB), in predicting compliance. A multi-centre survey was conducted using a questionnaire completed anonymously by contact lens wearers during the purchase of DDCLs. Three hundred and fifty-four questionnaires were returned. The survey comprised 58.5% females and 41.5% males (mean age 34±12years). Twenty-three percent of respondents were non-compliant with manufacturer-recommended replacement frequency (re-using DDCLs at least once). The main reason for re-using DDCLs was "to save money" (35%). Predictions of compliance behaviour (past behaviour or future intentions) on the basis of the two HBT was investigated through logistic regression analysis: both TPB factors (subjective norms and perceived behavioural control) were significant (pbehaviour and future intentions) and perceived benefit (only for past behaviour) as significant factors (pbehavioural control of daily replacement (behavioural control) are of paramount importance in improving compliance. With reference to the HBM, it is important to warn DDCLs wearers of the severity of a contact-lens-related eye infection, and to underline the possibility of its prevention. Copyright © 2016 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Dynamic Multi-Rigid-Body Systems with Concurrent Distributed Contacts: Theory and Examples

International Nuclear Information System (INIS)

TRINKLE, JEFFREY C.; TZITZOURIS, J.A.; PANG, J.S.

2001-01-01

Consider a system of rigid bodies with multiple concurrent contacts. The multi-rigid-body contact problem is to predict the accelerations of the bodies and the normal friction loads acting at the contacts. This paper presents theoretical results for the multi-rigid-body contact problem under the assumptions that one or more contacts occur over locally planar, finite regions and that friction forces are consistent with the maximum work inequality. Existence and uniqueness results are presented for this problem under mild assumptions on the system inputs. In addition, the performance of two different time-stepping methods for integrating the dynamics are compared on two simple multi-body systems

Dynamics of social contagions with limited contact capacity.

Science.gov (United States)

Wang, Wei; Shu, Panpan; Zhu, Yu-Xiao; Tang, Ming; Zhang, Yi-Cheng

2015-10-01

Individuals are always limited by some inelastic resources, such as time and energy, which restrict them to dedicate to social interaction and limit their contact capacities. Contact capacity plays an important role in dynamics of social contagions, which so far has eluded theoretical analysis. In this paper, we first propose a non-Markovian model to understand the effects of contact capacity on social contagions, in which each adopted individual can only contact and transmit the information to a finite number of neighbors. We then develop a heterogeneous edge-based compartmental theory for this model, and a remarkable agreement with simulations is obtained. Through theory and simulations, we find that enlarging the contact capacity makes the network more fragile to behavior spreading. Interestingly, we find that both the continuous and discontinuous dependence of the final adoption size on the information transmission probability can arise. There is a crossover phenomenon between the two types of dependence. More specifically, the crossover phenomenon can be induced by enlarging the contact capacity only when the degree exponent is above a critical degree exponent, while the final behavior adoption size always grows continuously for any contact capacity when degree exponent is below the critical degree exponent.

Assessing the accuracy of different simplified frictional rolling contact algorithms

Science.gov (United States)

Vollebregt, E. A. H.; Iwnicki, S. D.; Xie, G.; Shackleton, P.

2012-01-01

This paper presents an approach for assessing the accuracy of different frictional rolling contact theories. The main characteristic of the approach is that it takes a statistically oriented view. This yields a better insight into the behaviour of the methods in diverse circumstances (varying contact patch ellipticities, mixed longitudinal, lateral and spin creepages) than is obtained when only a small number of (basic) circumstances are used in the comparison. The range of contact parameters that occur for realistic vehicles and tracks are assessed using simulations with the Vampire vehicle system dynamics (VSD) package. This shows that larger values for the spin creepage occur rather frequently. Based on this, our approach is applied to typical cases for which railway VSD packages are used. The results show that particularly the USETAB approach but also FASTSIM give considerably better results than the linear theory, Vermeulen-Johnson, Shen-Hedrick-Elkins and Polach methods, when compared with the 'complete theory' of the CONTACT program.

FASTSIM2: a second-order accurate frictional rolling contact algorithm

Science.gov (United States)

Vollebregt, E. A. H.; Wilders, P.

2011-01-01

In this paper we consider the frictional (tangential) steady rolling contact problem. We confine ourselves to the simplified theory, instead of using full elastostatic theory, in order to be able to compute results fast, as needed for on-line application in vehicle system dynamics simulation packages. The FASTSIM algorithm is the leading technology in this field and is employed in all dominant railway vehicle system dynamics packages (VSD) in the world. The main contribution of this paper is a new version "FASTSIM2" of the FASTSIM algorithm, which is second-order accurate. This is relevant for VSD, because with the new algorithm 16 times less grid points are required for sufficiently accurate computations of the contact forces. The approach is based on new insights in the characteristics of the rolling contact problem when using the simplified theory, and on taking precise care of the contact conditions in the numerical integration scheme employed.

Why does Existential Threat Promote Intergroup Violence? Examining the Role of Retributive Justice and Cost-Benefit Utility Motivations.

Science.gov (United States)

Hirschberger, Gilad; Pyszczynski, Tom; Ein-Dor, Tsachi

2015-01-01

The current research examined the role of retributive justice and cost-benefit utility motivations in the process through which mortality salience increases support for violent responses to intergroup conflict. Specifically, previous research has shown that mortality salience often encourages political violence, especially when perceptions of retributive justice are activated. The current research examined whether mortality salience directly activates a justice mindset over a cost-benefit utility mindset, and whether this justice mindset is associated with support for political violence. In Study 1 (N = 209), mortality salience was manipulated among Israeli participants who then read about a Hamas attack on Israel with either no casualties or many casualties, after which justice and utility motivations for retribution were assessed. Study 2 (N = 112), examined whether the link between death primes and support for an Israeli preemptive strike on Iran's nuclear facilities is mediated by justice or cost-benefit utility considerations. Results of both studies revealed that primes of death increased justice-related motivations, and these motives, rather than utility motives, were associated with support for violence. Findings suggest that existential concerns often fuel violent intergroup conflict because they increase desire for retributive justice, rather than increase belief that violence is an effective strategy. These findings expand our knowledge on the motivations for intergroup violence, and shed experimental light on real-life eruptions of violent conflict indicating that when existential concerns are salient, as they often are during violent conflict, the decision to engage in violence often disregards the utility of violence, and leads to the preference for violent solutions to political problems - even when these solutions make little practical sense.

Metal semiconductor contacts and devices

CERN Document Server

Cohen, Simon S; Einspruch, Norman G

1986-01-01

VLSI Electronics Microstructure Science, Volume 13: Metal-Semiconductor Contacts and Devices presents the physics, technology, and applications of metal-semiconductor barriers in digital integrated circuits. The emphasis is placed on the interplay among the theory, processing, and characterization techniques in the development of practical metal-semiconductor contacts and devices.This volume contains chapters that are devoted to the discussion of the physics of metal-semiconductor interfaces and its basic phenomena; fabrication procedures; and interface characterization techniques, particularl

That's what friends are for: how intergroup friendships promote historically disadvantaged groups' substantive political representation.

Science.gov (United States)

Kokkonen, Andrej; Karlsson, David

2017-12-01

The interests of historically disadvantaged groups risk being overlooked if they are not present in the decision-making process. However, a mere presence in politics does not guarantee political success. Often groups need allies to promote their interests successfully. We argue that one way to identify such allies is to judge politicians by whether they have friends in historically disadvantaged groups, as intergroup friendships have been shown to make people understand and feel empathy for outgroups. In other words, intergroup friendships may function as an important complement to descriptive representation. We test our argument with a unique survey that asks all elected political representatives in Sweden's 290 municipalities (response rate 79 per cent) about their friendship ties to, and their representation of, five historically disadvantaged groups: women, immigrants, youths, pensioners and blue-collar workers. We find a strong correlation between representatives' friendship ties to these groups and their commitment to represent them. The correlation is especially strong for youths and blue-collar workers, which likely can be explained by the fact that these groups usually lack crucial political resources (such as experience and education). We conclude that friendship ties function as an important complement to descriptive representation for achieving substantive representation. © London School of Economics and Political Science 2017.

Student Teaching Abroad Inter-Group Outcomes: A Comparative, Country-Specific Analysis

Directory of Open Access Journals (Sweden)

Binbin Jiang

2010-11-01

Full Text Available As student diversity becomes the norm in U.S. schools, future teachers must be comprehensively prepared to work with the increasingly diverse student population through application of informed instruction that enhances general and individual student learning and outcomes. Teacher Education programs increasingly promote student teaching in international settings as a substantive step to develop teachers who embody these new competencies and instructional practices. The proposed paper presentation offers a framework and analysis highlighting similarities and differences between two groups of student teachers in Belize (2005 and 2008. Findings are comparative and relate to the type and degree of (1 cultural-, professional-, and character-development influences on student teachers, and (2 emergent common intergroup patterns.

CRS and Guarded Logics: a fruitful contact

NARCIS (Netherlands)

van Benthem, J.; Andréka, H.; Ferenczi, M.; Németi, I.

2013-01-01

Back and forth between algebra and model theory. Algebra and model theory are complementary stances in the history of logic, and their interaction continues to spawn new ideas, witness the interface of First-Order Logic and Cylindric Algebra. This chapter is about a more specialized contact: the

Psychological Theories of Acculturation

DEFF Research Database (Denmark)

Ozer, Simon

2017-01-01

advancements, together with greater mobility. Acculturation psychology aims to comprehend the dynamic psychological processes and outcomes emanating from intercultural contact. Acculturation psychology has been a growing field of research within cross-cultural psychology. Today, psychological theories......The proliferation of cultural transition and intercultural contact has highlighted the importance of psychological theories of acculturation. Acculturation, understood as contact between diverse cultural streams, has become prevalent worldwide due to technological, economical, and educational...... of acculturation also include cognate disciplines such as cultural psychology, social psychology, sociology, and anthropology.The expansion of psychological theories of acculturation has led to advancements in the field of research as well as the bifurcation of epistemological and methodological approaches...

The Austrians were surprised that I didn’t speak German”: The role of language in Czech-Austrian relations

Czech Academy of Sciences Publication Activity Database

Petrjánošová, Magda; Graf, Sylvie

2012-01-01

Roč. 22, č. 4 (2012), s. 539-557 ISSN 1210-3055 R&D Projects: GA ČR GAP407/10/2394 Institutional support: RVO:68081740 Keywords : content analysis * critical discursive analysis * intergroup contact * intergroup attitudes * communication * language Subject RIV: AN - Psychology

Scalable algorithms for contact problems

CERN Document Server

Dostál, Zdeněk; Sadowská, Marie; Vondrák, Vít

2016-01-01

This book presents a comprehensive and self-contained treatment of the authors’ newly developed scalable algorithms for the solutions of multibody contact problems of linear elasticity. The brand new feature of these algorithms is theoretically supported numerical scalability and parallel scalability demonstrated on problems discretized by billions of degrees of freedom. The theory supports solving multibody frictionless contact problems, contact problems with possibly orthotropic Tresca’s friction, and transient contact problems. It covers BEM discretization, jumping coefficients, floating bodies, mortar non-penetration conditions, etc. The exposition is divided into four parts, the first of which reviews appropriate facets of linear algebra, optimization, and analysis. The most important algorithms and optimality results are presented in the third part of the volume. The presentation is complete, including continuous formulation, discretization, decomposition, optimality results, and numerical experimen...

On ruled surface in 3-dimensional almost contact metric manifold

Science.gov (United States)

Karacan, Murat Kemal; Yuksel, Nural; Ikiz, Hasibe

In this paper, we study ruled surface in 3-dimensional almost contact metric manifolds by using surface theory defined by Gök [Surfaces theory in contact geometry, PhD thesis (2010)]. We also studied the theory of curves using cross product defined by Camcı. In this study, we obtain the distribution parameters of the ruled surface and then some results and theorems are presented with special cases. Moreover, some relationships among asymptotic curve and striction line of the base curve of the ruled surface have been found.

The balanced ideological antipathy model: explaining the effects of ideological attitudes on inter-group antipathy across the political spectrum.

Science.gov (United States)

Crawford, Jarret T; Mallinas, Stephanie R; Furman, Bryan J

2015-12-01

We introduce the balanced ideological antipathy (BIA) model, which challenges assumptions that right-wing authoritarianism (RWA) and social dominance orientation (SDO) predict inter-group antipathy per se. Rather, the effects of RWA and SDO on antipathy should depend on the target's political orientation and political objectives, the specific components of RWA, and the type of antipathy expressed. Consistent with the model, two studies (N = 585) showed that the Traditionalism component of RWA positively and negatively predicted both political intolerance and prejudice toward tradition-threatening and -reaffirming groups, respectively, whereas SDO positively and negatively predicted prejudice (and to some extent political intolerance) toward hierarchy-attenuating and -enhancing groups, respectively. Critically, the Conservatism component of RWA positively predicted political intolerance (but not prejudice) toward each type of target group, suggesting it captures the anti-democratic impulse at the heart of authoritarianism. Recommendations for future research on the relationship between ideological attitudes and inter-group antipathy are discussed. © 2015 by the Society for Personality and Social Psychology, Inc.

Cultural influences on neural basis of intergroup empathy.

Science.gov (United States)

Cheon, Bobby K; Im, Dong-Mi; Harada, Tokiko; Kim, Ji-Sook; Mathur, Vani A; Scimeca, Jason M; Parrish, Todd B; Park, Hyun Wook; Chiao, Joan Y

2011-07-15

Cultures vary in the extent to which people prefer social hierarchical or egalitarian relations between individuals and groups. Here we examined the effect of cultural variation in preference for social hierarchy on the neural basis of intergroup empathy. Using cross-cultural neuroimaging, we measured neural responses while Korean and American participants observed scenes of racial ingroup and outgroup members in emotional pain. Compared to Caucasian-American participants, Korean participants reported experiencing greater empathy and elicited stronger activity in the left temporo-parietal junction (L-TPJ), a region previously associated with mental state inference, for ingroup compared to outgroup members. Furthermore, preferential reactivity within this region to the pain of ingroup relative to outgroup members was associated with greater preference for social hierarchy and ingroup biases in empathy. Together, these results suggest that cultural variation in preference for social hierarchy leads to cultural variation in ingroup-preferences in empathy, due to increased engagement of brain regions associated with representing and inferring the mental states of others. Copyright © 2011 Elsevier Inc. All rights reserved.

Effectiveness of a knowledge-contact program in improving nursing students' attitudes and emotional competence in serving people living with HIV/AIDS.

Science.gov (United States)

Yiu, Jessie W; Mak, Winnie W S; Ho, Winnie S; Chui, Ying Yu

2010-07-01

This study compared the effectiveness of an AIDS knowledge-only program (knowledge) with a combined program of AIDS knowledge and contact with people having HIV/AIDS (PHA) (knowledge-contact) in reducing nursing students' stigma and discrimination towards PHA and in enhancing their emotional competence to serve PHA. Eighty-nine nursing students from two universities in Hong Kong were randomly assigned to either the knowledge or the knowledge-contact condition. All participants completed measures of AIDS knowledge, stigmatizing attitudes, fear of contagion, willingness to treat, positive affect, and negative affect at pre-test, post-test, and six-week follow-up. Findings showed that in both groups, significant improvement in AIDS knowledge, stigmatizing attitudes, fear of contagion, willingness to treat, and negative affect were found at post-test. The effects on AIDS knowledge, fear of contagion, willingness to treat, and negative affect were sustained at follow-up for both groups. Intergroup comparisons at post-test showed that the effectiveness of knowledge-contact program was significantly greater than knowledge program in improving stigmatizing attitudes. No significant difference between the two groups was found at follow-up. Findings showed the short-term effect of contact in improving nursing students' attitudes and emotional competence in serving PHA. Implications for research and training of nursing staff were discussed. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

[Effects of subliminal mere exposure to group members on intergroup evaluation: category evaluation measured in the Implicit Association Test (IAT)].

Science.gov (United States)

Kawakami, Naoaki; Yoshida, Fujio

2010-10-01

This study investigated the effects of subliminal mere exposure to ingroup or outgroup members on intergroup evaluation as measured in the Implicit Association Test (IAT). Participants first memorized the members of two groups. Then, they were assigned to either group by lot, and completed the IAT for intergroup evaluation (Time 1). In the next phase, half the participants were subliminally exposed to ingroup members and half to outgroup members. Upon completion of the exposure, the same IAT was administered at Time 2. The results showed that participants who were exposed to ingroup members evaluated the ingroup more positively at Time 2 than at Time 1. Participants who were exposed to outgroup members did not show an effect toward the outgroup. The finding that the mere exposure effect occurred only for the ingroup exposure condition suggests that unconscious awareness of the ingroup enhances the mere exposure effect.

Negative and positive externalities in intergroup conflict: exposure to the opportunity to help the outgroup reduces the inclination to harm it.

Science.gov (United States)

Weisel, Ori

2015-01-01

Outgroup hate, in the context of intergroup conflict, can be expressed by harming the outgroup, but also by denying it help. Previous work established that this distinction-whether the externality on the outgroup is negative or positive-has an important effect on the likelihood of outgroup hate emerging as a motivation for individual participation in intergroup conflict. The current work uses a within-subject design to examine the behavior of the same individuals in intergroup conflict with negative and positive externalities on the outgroup. Each participant made two choices, one for each type of externality, and the order was counter balanced. The main results are that (1) behavior is fairly consistent across negative and positive externalities, i.e., the tendency to display outgroup hate by harming the outgroup is correlated with the tendency to display outgroup hate by avoiding to help the outgroup; (2) People are reluctant to harm the outgroup after being exposed to the opportunity to help it; (3) Groupness-the degree to which people care about their group and its well-being-is related to outgroup hate only when participants encounter the opportunity to harm the outgroup first (before they encounter the opportunity to help it). In this setting the relationship between groupness and outgroup hate spilled over to the subsequent interaction, where it was possible to help the outgroup. When the opportunity to help the outgroup was encountered first, groupness was not related to outgroup hate.

Negative and positive externalities in intergroup conflict: Exposure to the opportunity to help the outgroup reduces the inclination to harm it

Directory of Open Access Journals (Sweden)

Ori eWeisel

2015-10-01

Full Text Available Outgroup hate, in the context of intergroup conflict, can be expressed by harming the outgroup, but also by denying it help.Previous work established that this distinction---whether the externality on the outgroup is negative or positive---has an important effect on the likelihood of outgroup hate emerging as a motivation for individual participation in intergroup conflict.The current work uses a within-subject design to examine the behaviour of the same individuals in intergroup conflict with negative and positive externalities on the outgroup.Each participant made two choices, one for each type of externality, and the order was counter balanced.The main results are that(1 behaviour is fairly consistent across negative and positive externalities, i.e., the tendency to display outgroup hate by harming the outgroup is correlated with the tendency to display outgroup hate by avoiding to help the outgroup; (2 People are reluctant to harm the outgroup after being exposed to the opportunity to help it; (3 emph{Groupness}---the degree to which people care about their group and its well-being---is related to outgroup hate only when participants encounter the opportunity to harm the outgroup first (before they encounter the opportunity to help it. In this setting the relationship between groupness and outgroup hate spilled over to the subsequent interaction, where it was possible to help the outgroup. When the opportunity to help the outgroup was encountered first, groupness was not related to outgroup hate.

Surface tension and contact angles: Molecular origins and associated microstructure

Science.gov (United States)

Davis, H. T.

1982-01-01

Gradient theory converts the molecular theory of inhomogeneous fluid into nonlinear boundary value problems for density and stress distributions in fluid interfaces, contact line regions, nuclei and microdroplets, and other fluid microstructures. The relationship between the basic patterns of fluid phase behavior and the occurrence and stability of fluid microstructures was clearly established by the theory. All the inputs of the theory have molecular expressions which are computable from simple models. On another level, the theory becomes a phenomenological framework in which the equation of state of homogeneous fluid and sets of influence parameters of inhomogeneous fluids are the inputs and the structures, stress tensions and contact angles of menisci are the outputs. These outputs, which find applications in the science and technology of drops and bubbles, are discussed.

Computational Contact Mechanics Geometrically Exact Theory for Arbitrary Shaped Bodies

CERN Document Server

Konyukhov, Alexander

2013-01-01

This book contains a systematical analysis of geometrical situations  leading to  contact pairs -- point-to-surface, surface-to-surface, point-to-curve, curve-to-curve and curve-to-surface.  Each contact pair  is inherited with a special coordinate system based on its geometrical properties such as a Gaussian surface coordinate system or a Serret-Frenet curve coordinate system.  The formulation in a covariant form allows in a straightforward fashion to consider various constitutive relations for a  certain pair such as anisotropy for both frictional and structural parts. Then standard methods well known in computational contact mechanics such as penalty, Lagrange multiplier methods, combination of both and others  are formulated in these coordinate systems. Such formulations require then the powerful apparatus of differential geometry of surfaces and curves as well as of convex analysis. The final goals of such transformations are  then ready-for-implementation numerical algorithms within the finite e...

White and Black American Children’s Implicit Intergroup Bias

Science.gov (United States)

Newheiser, Anna-Kaisa; Olson, Kristina R.

2011-01-01

Despite a decline in explicit prejudice, adults and children from majority groups (e.g., White Americans) often express bias implicitly, as assessed by the Implicit Association Test. In contrast, minority-group (e.g., Black American) adults on average show no bias on the IAT. In the present research, representing the first empirical investigation of whether Black children’s IAT responses parallel those of Black adults, we examined implicit bias in 7–11-year-old White and Black American children. Replicating previous findings with adults, whereas White children showed a robust ingroup bias, Black children showed no bias. Additionally, we investigated the role of valuing status in the development of implicit bias. For Black children, explicit preference for high status predicted implicit outgroup bias: Black children who explicitly expressed high preference for rich (vs. poor) people showed an implicit preference for Whites comparable in magnitude to White children’s ingroup bias. Implications for research on intergroup bias are discussed. PMID:22184478

Peer Effects, Social Networks, and Intergroup Competition in the Workplace

DEFF Research Database (Denmark)

Kato, Takao; Shu, Pian

novel evidence on the interplay between social networks (urban resident group and rural migrant group) and peer effects. Specifically, we find that a worker puts in more effort when she is working with more able outgroup teammates but not when working with more able ingroup teammates, pointing...... to intergroup competition as a powerful source of the peer effects. Such peer effects across the social network, combined with the presence of incentive to outperform teammates at this firm, are largely consistent with recent experimental evidence on the important role that group identities play in facilitating......Using weekly data for defect rates (proportion of defective output) for all weavers in a Chinese textile firm during a 12 months (April 2003 - March 2004) period, we provide some of the first rigorous evidence on the presence and nature of peer effects in the manufacturing workplace. First...

Us versus Them in Context: Meta-Analysis as a Tool for Geotemporal Trends in Intergroup Relations

Directory of Open Access Journals (Sweden)

Tania B. Huedo-Medina

2010-12-01

Full Text Available

The increasing availability of studies from many nations offers important potential insights into group-based psychology and behavior, conflict, and violence. Nonetheless, to date, few cross-national or cultural comparisons of study findings have been made, representing a gap in our understanding of the historical causes and courses of inter-group conflict in current comparative approaches. Meta-analytic methods offer researchers the ability to combine data from studies with groups as well as across time. Our review of statistical methods available for comparative analyses in inter-group research found strengths and limitations for understanding group differences, conflict, and violence, and meta-analytic methods address these limitations by exploring potential structural-level moderators and by identifying how temporal and geographical variations may relate directly to group-based variables. Such methods can contribute to our understanding of broad structural effects on group-based variables by elucidating the mechanisms underlying them.

Differences within the groups of physicians and managers in Dutch hospitals providing leads for intergroup cooperation : Running head: group differences in hospitals

NARCIS (Netherlands)

van Harten, Willem H.

2010-01-01

Background: Effective cooperation between physicians and managers is difficult to achieve but is an important factor in successfully implementing improvement initiatives in hospitals. Intergroup literature suggests that large differences between groups hinder effective cooperation. - Purposes:

Impedance learning for robotic contact tasks using natural actor-critic algorithm.

Science.gov (United States)

Kim, Byungchan; Park, Jooyoung; Park, Shinsuk; Kang, Sungchul

2010-04-01

Compared with their robotic counterparts, humans excel at various tasks by using their ability to adaptively modulate arm impedance parameters. This ability allows us to successfully perform contact tasks even in uncertain environments. This paper considers a learning strategy of motor skill for robotic contact tasks based on a human motor control theory and machine learning schemes. Our robot learning method employs impedance control based on the equilibrium point control theory and reinforcement learning to determine the impedance parameters for contact tasks. A recursive least-square filter-based episodic natural actor-critic algorithm is used to find the optimal impedance parameters. The effectiveness of the proposed method was tested through dynamic simulations of various contact tasks. The simulation results demonstrated that the proposed method optimizes the performance of the contact tasks in uncertain conditions of the environment.

Changing Lenses: Using participatory photography for wide-angle intergroup perspectives on peace and conflict for social change

OpenAIRE

Tan de Bibiana, Marcus

2017-01-01

The potential for art in peacebuilding has shown success but not complete acceptance in the peacebuilding field. Participatory photography’s method of photovoice has shown effective as a unique participatory action research tool able to allow users to communicate deeply on sensitive subjects with potential to influence larger social change. Participatory photography programs involving intergroup conflict or tensions presents an important relational component for practitioners and stakeholders...

In intergroup conflict, self-sacrifice is stronger among pro-social individuals, and parochial altruism emerges especially among cognitively taxed individuals

NARCIS (Netherlands)

de Dreu, C.K.W.; Dussel, D.B.; ten Velden, F.S.

2015-01-01

Parochial altruism is decomposed in a tendency to benefit the in-group along with a tendency to ignore, derogate, and harm rivaling out-groups. Building off recent work suggesting that decisions to cooperate can be relatively fast and intuitive, we examine parochial altruism in intergroup conflict

Predictors of disability-related attitudes: considering self-esteem, communication apprehension, contact, and geographic location

Directory of Open Access Journals (Sweden)

Magsamen-Conrad K

2016-12-01

Full Text Available Kate Magsamen-Conrad,1 Dinah Tetteh,2 Yen-I Lee3 1Department of Communication, Bowling Green State University, Bowling Green, OH, 2Department of Communication, Arkansas State University, Jonesboro, AR, 3Grady College of Journalism and Mass Communication, University of Georgia, Athens, GA, USA Abstract: Individuals’ attitudes about persons with disability (PwD strongly affect differently-abled persons’ quality of life and position in society. Some research offers support for the ability of systematic, supported, longitudinal contact between different groups of individuals to improve attitudes. College campuses, in particular, offer a potentially useful arena in which to facilitate this type of contact. This study explored contextual factors (eg, geographic region, biological sex and predictors of disability-related attitudes among a college student population to determine strategies for course-based intervention design (eg, as community-engaged or service-learning initiatives. Surveying participants from universities in two regions of the United States, we found that self-esteem, audience-based communication apprehension, and contact with PwD explain more than 50% of the variance in disability-related attitudes. Further, we found that geographic location affects both self-esteem and audience-based communication apprehension (communicating/interacting with PwD. We discuss the implications for community engagement and/or service learning and highlight the importance of partnerships among relevant community stakeholders, including university faculty, students, and staff. Keywords: community engagement, service learning, intervention, regional culture, PwD, intergroup, quality of life, college students, community partnerships

Intergroup Discrimination in Positive and Negative Outcome Allocations: Impact of Stimulus Valence, Relative Group Status, and Relative Group Size.

Science.gov (United States)

Otten, Sabine; And Others

1996-01-01

Three studies investigated the determination of social discrimination by the valence of stimuli that are allocated between groups. The studies were based on either the minimal group paradigm or a more reality-based laboratory intergroup setting, with stimulus valence, group status, and group size as factors and with pull scores on Tajfel matrices…

Friendships fighting prejudice: a longitudinal perspective on adolescents' cross-group friendships with immigrants.

Science.gov (United States)

Titzmann, Peter F; Brenick, Alaina; Silbereisen, Rainer K

2015-06-01

Increasingly, adolescents are growing up in multiethnic multicultural societies. While intergroup prejudice can threaten the multicultural societal cohesion, intergroup friendships are strong predictors of reduced prejudice. Thus, more research is needed to fully understand the development of intergroup friendships and their relations to less prejudicial attitudes. This study addressed two major developmental research questions: first, whether longitudinal patterns of intergroup friendships of native adolescents (i.e., whether or not a native German adolescent has a friendship with an immigrant at different points in time) relate to changes in rates of prejudice about immigrants. Second, whether these friendship patterns that unfold over time can be predicted by contact opportunities, attitudes, subjective norms, and perceived behavioral control assessed at the beginning of the study. The sample included 372 native German adolescents (14.7 years of age at first assessment, 62.3% girls) who showed one of four friendship trajectories over the three annual assessments: they either maintained, gained, never had, or lost a friendship with an outgroup peer. In particular, results showed that adolescents who gained an intergroup friendship over the three time points showed a significant decrease in negative prejudice over the study. All four theorized predictors contributed to explain friendship trajectory membership. Generally, adolescents with many opportunities for contact, positive attitudes about contact, perceived positive social norms for contact, and high levels of behavioral control (self-efficacy) were more likely to maintain a friendship with an outgroup member than to follow any of the three other friendship trajectories (gain, lost, or never had). The pattern of predictions differed, however, depending on the specific pairs of friendship trajectories compared.

The Contact Dynamics method: A nonsmooth story

Science.gov (United States)

Dubois, Frédéric; Acary, Vincent; Jean, Michel

2018-03-01

When velocity jumps are occurring, the dynamics is said to be nonsmooth. For instance, in collections of contacting rigid bodies, jumps are caused by shocks and dry friction. Without compliance at the interface, contact laws are not only non-differentiable in the usual sense but also multi-valued. Modeling contacting bodies is of interest in order to understand the behavior of numerous mechanical systems such as flexible multi-body systems, granular materials or masonry. These granular materials behave puzzlingly either like a solid or a fluid and a description in the frame of classical continuous mechanics would be welcome though far to be satisfactory nowadays. Jean-Jacques Moreau greatly contributed to convex analysis, functions of bounded variations, differential measure theory, sweeping process theory, definitive mathematical tools to deal with nonsmooth dynamics. He converted all these underlying theoretical ideas into an original nonsmooth implicit numerical method called Contact Dynamics (CD); a robust and efficient method to simulate large collections of bodies with frictional contacts and impacts. The CD method offers a very interesting complementary alternative to the family of smoothed explicit numerical methods, often called Distinct Elements Method (DEM). In this paper developments and improvements of the CD method are presented together with a critical comparative review of advantages and drawbacks of both approaches. xml:lang="fr"

In Intergroup Conflict, Self-sacrifice is Stronger among Pro-social Individuals and Parochial Altruism Emerges specially among Cognitively Taxed Individuals

Directory of Open Access Journals (Sweden)

Carsten K.W. De Dreu

2015-05-01

Full Text Available Parochial altruism is decomposed in a tendency to benefit the in-group along with a tendency to ignore, derogate, and harm rivaling out-groups. Building off recent work suggesting that decisions to cooperate can be relatively fast and intuitive, we examine parochial altruism in intergroup conflict when cognitive deliberation is rendered difficult or not. Predictions were tested in an experiment using an incentivized Intergroup Prisoner’s Dilemma—Maximizing Differences Game (IPD-MD with ninety-five subjects classified as either pro-social or pro-self being randomly allocated to high vs. low impulse-control conditions. Results showed, first of all, that decisions to contribute and self-sacrifice were made faster than decisions not to contribute, and that longer decision time associated with less positive expectations of in-group members. Second, we observed that lowering impulse control with a difficult rather than easy Stroop Task increased the amount contributed to a pool that benefited in-group members while harming out-group members; thus reducing deliberation increased parochial altruism. Finally, results replicated earlier work showing that especially pro-social (versus pro-self individuals contributed more to the in-group and did not lower their contributions to the between-group pool that benefitted their in-group and, simultaneously, hurt the out-group. This pattern emerged independent of their impulse control. Thus, (in-group bounded cooperation is more prominent among individuals with strong rather than weak other-regarding preferences. Moreover, the intuitive tendency to cooperate may have evolved in the context of intergroup conflict and therefore is sharp-edged—in-group bounded and including willingness to aggress out-groups.

Vicarious retribution: the role of collective blame in intergroup aggression.

Science.gov (United States)

Lickel, Brian; Miller, Norman; Stenstrom, Douglas M; Denson, Thomas F; Schmader, Toni

2006-01-01

We provide a new framework for understanding 1 aspect of aggressive conflict between groups, which we refer to as vicarious retribution. Vicarious retribution occurs when a member of a group commits an act of aggression toward the members of an outgroup for an assault or provocation that had no personal consequences for him or her but which did harm a fellow ingroup member. Furthermore, retribution is often directed at outgroup members who, themselves, were not the direct causal agents in the original attack against the person's ingroup. Thus, retribution is vicarious in that neither the agent of retaliation nor the target of retribution were directly involved in the original event that precipitated the intergroup conflict. We describe how ingroup identification, outgroup entitativity, and other variables, such as group power, influence vicarious retribution. We conclude by considering a variety of conflict reduction strategies in light of this new theoretical framework.

The contact sport of rough surfaces

Science.gov (United States)

Carpick, Robert W.

2018-01-01

Describing the way two surfaces touch and make contact may seem simple, but it is not. Fully describing the elastic deformation of ideally smooth contacting bodies, under even low applied pressure, involves second-order partial differential equations and fourth-rank elastic constant tensors. For more realistic rough surfaces, the problem becomes a multiscale exercise in surface-height statistics, even before including complex phenomena such as adhesion, plasticity, and fracture. A recent research competition, the “Contact Mechanics Challenge” (1), was designed to test various approximate methods for solving this problem. A hypothetical rough surface was generated, and the community was invited to model contact with this surface with competing theories for the calculation of properties, including contact area and pressure. A supercomputer-generated numerical solution was kept secret until competition entries were received. The comparison of results (2) provides insights into the relative merits of competing models and even experimental approaches to the problem.

A Partial Equilibrium Theory for Drops and Capillary Liquids

International Nuclear Information System (INIS)

Searcy, Alan W.; Beruto, Dario T.; Barberis, Fabrizio

2006-01-01

The two-century old theory of Young and Laplace retains a powerful influence on surface and interface studies because it quantitatively predicts the height of rise of capillary liquids from the contact angles of drops. But the classical theory does not acknowledge that equilibrium requires separate minimization of partial free energies of one-component liquids bonded to immiscible solids. We generalize a theorem of Gibbs and Curie to obtain a partial equilibrium (PE) theory that does so and that also predicts the height of capillary rise from contact angles of drops. Published observations and our own measurements of contact angles of water bonded to glass and Teflon surfaces support the conclusion of PE theory that contact angles of meniscuses and of drops are different dependent variables. PE theory provides thermodynamic and kinetic guidance to nanoscale processes that the classical theory obscures, as illustrated by examples in our concluding section

The Politicized Motivations of Volunteers in the Refugee Crisis: Intergroup Helping as the Means to Achieve Social Change

Directory of Open Access Journals (Sweden)

Anna Kende

2017-05-01

Full Text Available The refugee crisis in the summer of 2015 mobilized thousands of volunteers in Hungary to help refugees on their journey through Europe despite the government’s hostile stance. We conducted a survey (N = 1459 among people who were active in supporting refugees and providing services to them to test the hypothesis of whether volunteers in the context of this humanitarian crisis had social change motivations similar to those engaged in direct political activism. Hierarchical regression analysis and mediation analysis revealed the importance of opinion-based identity and moral convictions as predictors of volunteerism, while efficacy beliefs and anger only predicted political activism. Our findings suggest that volunteers engaged in helping refugees based on motivations previously described as drivers of mobilization for political activism, but chose volunteerism to alleviate the problems embedded in the intergroup situation. Although the context of the refugee crisis in Hungary may have been somewhat unique, these findings have implications for other asymmetrical politicized intergroup relations in which advantaged group members can choose to offer humanitarian aid, engage in political actions to change the situation, or do both.

Multiple emotions: a person-centered approach to the relationship between intergroup emotion and action orientation.

Science.gov (United States)

Fernando, Julian W; Kashima, Yoshihisa; Laham, Simon M

2014-08-01

Although a great deal of research has investigated the relationship between emotions and action orientations, most studies to date have used variable-centered techniques to identify the best emotion predictor(s) of a particular action. Given that people frequently report multiple or blended emotions, a profitable area of research may be to adopt person-centered approaches to examine the action orientations elicited by a particular combination of emotions or "emotion profile." In two studies, across instances of intergroup inequality in Australia and Canada, we examined participants' experiences of six intergroup emotions: sympathy, anger directed at three targets, shame, and pride. In both studies, five groups of participants with similar emotion profiles were identified by cluster analysis and their action orientations were compared; clusters indicated that the majority of participants experienced multiple emotions. Each action orientation was also regressed on the six emotions. There were a number of differences in the results obtained from the person-centered and variable-centered approaches. This was most apparent for sympathy: the group of participants experiencing only sympathy showed little inclination to perform prosocial actions, yet sympathy was a significant predictor of numerous action orientations in regression analyses. These results imply that sympathy may only prompt a desire for action when experienced in combination with other emotions. We suggest that the use of person-centered and variable-centered approaches as complementary analytic strategies may enrich research into not only the affective predictors of action, but emotion research in general.

If you don’t like them by now – what makes you like them next year? Social-cognitive and social predictors of prejudice in school children in a two-wave longitudinal study

OpenAIRE

Farhan, Tina

2009-01-01

German society is becoming more ethnically diverse – almost every fifth person has an immigration background (Statistisches Bundesamt, 2007). Unprejudiced intergroup attitudes are important in diverse societies to prevent intergroup tensions and discrimination. Theories of prejudice acquisition and development assume that intergroup attitudes are formed during childhood and adolescence (Aboud, 1988; Bar-Tal & Teichman, 2005; ...

Contested collaboration: A descriptive model of intergroup communication in information system design

DEFF Research Database (Denmark)

Sonnenwald, D.H.

1995-01-01

. The model describes design phases, roles, themes, and intergroup communication networks as they evolve throughout the design process and characterizes design as a process of ''contested collaboration.'' It is a first step towards a predictive design model that suggests strategies which may help participants......Many information system design situations today include users, designers, and developers who, with their own unique group and individual perspectives, need to interact so that they can come to a working understanding of how the information system being developed will coexist with and ideally...... support patterns of work activities, social groups, and personal beliefs. In these situations, design is fundamentally an interactive process that requires communication among users, designers, and developers. However, communication among these groups is often difficult although of paramount importance...

The Josephson effect in atomic contacts; Effect Josephson dans les contacts atomiques

Energy Technology Data Exchange (ETDEWEB)

Chauvin, M

2005-11-15

The Josephson effect appears when a weak-link establishes phase coherence between two superconductors. A unifying theory of this effect emerged in the 90's within the framework of mesoscopic physics. Based on two cornerstone concepts, conduction channels and Andreev reflection, it predicts the current-phase relation for the most basic weak-link: a single conduction channel of arbitrary transmission. This thesis illustrates this mesoscopic point of view with experiments on superconducting atomic size contacts. In particular, we have focused on the supercurrent peak around zero voltage, put into evidence the ac Josephson currents in a contact under constant bias voltage (Shapiro resonances and photon assisted multiple Andreev reflections), and performed direct measurements of the current-phase relation. (author)

Can Innate, modular "foundations" explain morality? Challenges for Haidt's Moral Foundations Theory.

Science.gov (United States)

Suhler, Christopher L; Churchland, Patricia

2011-09-01

Jonathan Haidt's Moral Foundations Theory is an influential scientific account of morality incorporating psychological, developmental, and evolutionary perspectives. The theory proposes that morality is built upon five innate "foundations," each of which is believed to have been selected for during human evolution and, subsequently, tuned-up by learning during development. We argue here that although some general elements of Haidt's theory are plausible, many other important aspects of his account are seriously flawed. First, innateness and modularity figure centrally in Haidt's account, but terminological and conceptual problems foster confusion and ambiguities. Second, both the theory's proposed number of moral foundations and its taxonomy of the moral domain appear contrived, ignoring equally good candidate foundations and the possibility of substantial intergroup differences in the foundations' contents. Third, the mechanisms (viz., modules) and categorical distinctions (viz., between foundations) proposed by the theory are not consilient with discoveries in contemporary neuroscience concerning the organization, functioning, and development of the brain. In light of these difficulties, we suggest that Haidt's theory is inadequate as a scientific account of morality. Nevertheless, the theory's weaknesses are instructive, and hence, criticism may be useful to psychologists, neuroscientists, and philosophers attempting to advance theories of morality, as well as to researchers wishing to invoke concepts such as innateness and modularity more generally.

The Effects of Living in Segregated vs. Mixed Areas in Northern Ireland: A Simultaneous Analysis of Contact and Threat Effects in the Context of Micro-Level Neighbourhoods

Directory of Open Access Journals (Sweden)

Joanne Hughes

2008-06-01

Full Text Available This study examines the consequences of living in segregated and mixed neighbourhoods on ingroup bias and offensive action tendencies, taking into consideration the role of intergroup experiences and perceived threat. Using adult data from a cross-sectional survey in Belfast, Northern Ireland, we tested a model that examined the relationship between living in segregated (N = 396 and mixed (N = 562 neighbourhoods and positive contact, exposure to violence, perceived threat and outgroup orientations. Our results show that living in mixed neighbourhoods was associated with lower ingroup bias and reduced offensive action tendencies. These effects were partially mediated by positive contact. However, our analysis also shows that respondents living in mixed neighbourhoods report higher exposure to political violence and higher perceived threat to physical safety. These findings demonstrate the importance of examining both social experience and threat perceptions when testing the relationship between social environment and prejudice.

Improving Racial and Ethnic Distribution and Intergroup Relations; An Advisory Report to the Board of Education, Vallejo Unified School District.

Science.gov (United States)

Gunsky, Frederic R.; And Others

As the result of field observation and a review of school data, this report presents the findings of a study of minority-group education and intergroup relations in the Vallejo Unified School District in California. It analyzes the racial and ethnic distribution o f students in the school district and describes the amount of equal educational…

Contact activation of blood-plasma coagulation

Science.gov (United States)

Golas, Avantika

Surface engineering of biomaterials with improved hemocompatibility is an imperative, given the widespread global need for cardiovascular devices. Research summarized in this dissertation focuses on contact activation of FXII in buffer and blood plasma frequently referred to as autoactivation. The extant theory of contact activation imparts FXII autoactivation ability to negatively charged, hydrophilic surfaces. According to this theory, contact activation of plasma involves assembly of proteins comprising an "activation complex" on activating surfaces mediated by specific chemical interactions between complex proteins and the surface. This work has made key discoveries that significantly improve our core understanding of contact activation and unravel the existing paradigm of plasma coagulation. It is shown herein that contact activation of blood factor XII (FXII, Hageman factor) in neat-buffer solution exhibits a parabolic profile when scaled as a function of silanized-glass-particle activator surface energy (measured as advancing water adhesion tension t°a=g° Iv costheta in dyne/cm, where g°Iv is water interfacial tension in dyne/cm and theta is the advancing contact angle). Nearly equal activation is observed at the extremes of activator water-wetting properties --36 moderated by adsorption of plasma proteins unrelated to coagulation through an "adsorption-dilution" effect that blocks FXII contact with hydrophobic activator surfaces. The adsorption-dilution effect explains the apparent specificity for hydrophilic activators pursued by earlier investigators. Finally a comparison of FXII autoactivation in buffer, serum, protein cocktail, and plasma solutions is shown herein. Activation of blood plasma coagulation in vitro by contact with material surfaces is demonstrably dependent on plasma-volume-to-activator-surface-area ratio. However, activation of factor XII dissolved in buffer, protein cocktail, heat-denatured serum, and FXI deficient plasma does not

The More the Merrier? The Effects of Type of Cultural Diversity on Exclusionary Immigration Attitudes in Switzerland

Directory of Open Access Journals (Sweden)

Eva G. T. Green

2010-12-01

Full Text Available

Who confronts prejudice?: the role of implicit theories in the motivation to confront prejudice.

Science.gov (United States)

Rattan, Aneeta; Dweck, Carol S

2010-07-01

Despite the possible costs, confronting prejudice can have important benefits, ranging from the well-being of the target of prejudice to social change. What, then, motivates targets of prejudice to confront people who express explicit bias? In three studies, we tested the hypothesis that targets who hold an incremental theory of personality (i.e., the belief that people can change) are more likely to confront prejudice than targets who hold an entity theory of personality (i.e., the belief that people have fixed traits). In Study 1, targets' beliefs about the malleability of personality predicted whether they spontaneously confronted an individual who expressed bias. In Study 2, targets who held more of an incremental theory reported that they would be more likely to confront prejudice and less likely to withdraw from future interactions with an individual who expressed prejudice. In Study 3, we manipulated implicit theories and replicated these findings. By highlighting the central role that implicit theories of personality play in targets' motivation to confront prejudice, this research has important implications for intergroup relations and social change.

MULTIVARIANT AND UNIVARIANT INTERGROUP DIFFERENCES IN THE INVESTIGATED SPECIFIC MOTOR SPACE BETWEEN RESPONDENTS JUNIORS AND SENIORS MEMBERS OF THE MACEDONIAN NATIONAL KARATE TEAM

Directory of Open Access Journals (Sweden)

Kеnan Аsani

2013-07-01

Full Text Available The aim is to establish intergroup multivariant and univariant investigated differences in specific motor space between respondents juniors and seniors members of the Macedonian karate team. The sample of 30 male karate respondents covers juniors on 16,17 and seniors over 18 years.In the research were applied 20 specific motor tests. Based on Graph 1 where it is presented multivariant analysis of variance Manova and Anova can be noted that respondents juniors and seniors, although not belonging to the same population are not different in multivariant understudied area.W. lambda of .19, Rao-wool R - Approximation of 1.91 degrees of freedom df 1 = 20 and df 2 = 9 provides the level of significance of p =, 16. Based on univariant analysis for each variable separately can be seen that has been around intergroup statistically significant difference in seven SMAEGERI (kick in the sack with favoritism leg mae geri for 10 sec., SMAVASI (kick in the sack with favoritism foot mavashi geri by 10 sec., SUSIRO (kick in the sack with favoritism leg ushiro geri for 10 sec., SKIZAME (kick in the sack with favoritism hand kizame cuki for 10 sec., STAPNSR (taping with foot in sagital plane for 15 sec. SUDMNR (hitting a moving target with weaker hand and SUDMPN (hitting a moving target with favoritism foot of twenty applied manifest variables. There are no intergroup differences in multivariant investigated specific - motor space among the respondents juniors and seniors members of the Macedonian karate team. Based on univariant analysis for each variable separately can be seen that has been around intergroup statistically significant difference in seven SMAEGERI (kick in the sack with favoritism leg mae geri for 10 sec., SMAVASI (kick in the sack with favoritism foot mavashi geri by 10 sec., SUSIRO (kick in the sack with favoritism leg ushiro geri for 10 sec., SKIZAME (kick in the sack with favoritism hand kizame cuki for 10 sec., STAPNSR (taping with foot in

Non-contact transportation using near-field acoustic levitation

Science.gov (United States)

Ueha; Hashimoto; Koike

2000-03-01

Near-field acoustic levitation, where planar objects 10 kg in weight can levitate stably near the vibrating plate, is successfully applied both to non-contact transportation of objects and to a non-contact ultrasonic motor. Transporting apparatuses and an ultrasonic motor have been fabricated and their characteristics measured. The theory of near-field acoustic levitation both for a piston-like sound source and a flexural vibration source is also briefly described.

Amino acid empirical contact energy definitions for fold recognition in the space of contact maps

Directory of Open Access Journals (Sweden)

Fogolari Federico

2003-02-01

Full Text Available Abstract Background Contradicting evidence has been presented in the literature concerning the effectiveness of empirical contact energies for fold recognition. Empirical contact energies are calculated on the basis of information available from selected protein structures, with respect to a defined reference state, according to the quasi-chemical approximation. Protein-solvent interactions are estimated from residue solvent accessibility. Results In the approach presented here, contact energies are derived from the potential of mean force theory, several definitions of contact are examined and their performance in fold recognition is evaluated on sets of decoy structures. The best definition of contact is tested, on a more realistic scenario, on all predictions including sidechains accepted in the CASP4 experiment. In 30 out of 35 cases the native structure is correctly recognized and best predictions are usually found among the 10 lowest energy predictions. Conclusion The definition of contact based on van der Waals radii of alpha carbon and side chain heavy atoms is seen to perform better than other definitions involving only alpha carbons, only beta carbons, all heavy atoms or only backbone atoms. An important prerequisite for the applicability of the approach is that the protein structure under study should not exhibit anomalous solvent accessibility, compared to soluble proteins whose structure is deposited in the Protein Data Bank. The combined evaluation of a solvent accessibility parameter and contact energy allows for an effective gross screening of predictive models.

Religion insulates ingroup evaluations: the development of intergroup attitudes in India.

Science.gov (United States)

Dunham, Yarrow; Srinivasan, Mahesh; Dotsch, Ron; Barner, David

2014-03-01

Research on the development of implicit intergroup attitudes has placed heavy emphasis on race, leaving open how social categories that are prominent in other cultures might operate. We investigate two of India's primary means of social distinction, caste and religion, and explore the development of implicit and explicit attitudes towards these groups in minority-status Muslim children and majority-status Hindu children, the latter drawn from various positions in the Hindu caste system. Results from two tests of implicit attitudes find that caste attitudes parallel previous findings for race: higher-caste children as well as lower-caste children have robust high-caste preferences. However, results for religion were strikingly different: both lower-status Muslim children and higher-status Hindu children show strong implicit ingroup preferences. We suggest that religion may play a protective role in insulating children from the internalization of stigma. © 2013 John Wiley & Sons Ltd.

Effect of contact angle and contact angle hysteresis on the floatability of spheres at the air-water interface.

Science.gov (United States)

Feng, Dong-Xia; Nguyen, Anh V

2017-10-01

The floatability of solid particles on the water surface governs many natural phenomena and industrial processes including film flotation and froth flotation separation of coal and valuable minerals. For many years, the contact angle (CA) has been postulated as the key factor in determining the particle floatability. Indeed, the maximum force (tenacity) supporting the flotation of fine spheres was conjectured to occur when the apical angle of the contact circle is equal to the contact angle. In this paper, the model predictions are reviewed and compared with experimental results. It is shown that CA can be affected by many physical and chemical factors such as surface roughness and chemical heterogeneity and can have a range of values known as the CA hysteresis. This multiple-valued CA invalidates the available theories on the floatability of spheres. Even the intuitive replacement of CA by the advancing (maximum) CA in the classical theories can be wrong. A few new examples are also reviewed and analyzed to demonstrate the significance of CA variation in controlling the particle floatability. They include the pinning of the contact line at the sharp edge, known as the Gibbs inequality condition, and the nearby interaction among floating particles, known as lateral inter-particle interaction. It is concluded that our quantitative understanding of the floatability of real particles being irregular and heterogeneous both morphologically and chemically is still far from being satisfactory. Copyright © 2017 Elsevier B.V. All rights reserved.

Postcolonial Trauma Theory in the Contact Zone: The Strategic Representation of Grief in Edwidge Danticat’s Claire of the Sea Light

Directory of Open Access Journals (Sweden)

Silvia Martínez-Falquina

2015-11-01

Full Text Available This article starts by engaging in a dialogue with the most relevant postcolonial emendations to trauma theory, addressed to both its aporetic and its therapeutic trends, and it goes on to reflect on the state of the decolonizing trauma theory project, critically examining the motivations behind it as well as some of the problems it still encounters, like the risk of objectification and revictimization of postcolonial peoples, the blurring of their trauma particularities, and the appropriation of their experience. Then, it proposes an alternative understanding of postcolonial trauma theory as a contact zone where trauma criticism and the postcolony are interrelated and mutually transformed, and where unequal power relations are also attended to. Acknowledging the postcolony as a site of theory production rather than the object of external definition, it proceeds to analyze Edwidge Danticat’s short story cycle Claire of the Sea Light: its strategic representation of grief—which she achieves through the short story cycle structure and overall in-betweenness and ambivalence in symbols and characterization—puts Haitians on the critical map of trauma, fighting invisibility and oblivion, but it simultaneously resists an appropriation of Haitian experience by rejecting any monolithic view on Haiti and refusing to fit into a predetermined template.

Breaking Ground: A Study of Gestalt Therapy Theory and Holland's Theory of Vocational Choice.

Science.gov (United States)

Hartung, Paul J.

In both Gestalt therapy and Holland's theory of vocational choice, person-environment interaction receives considerable emphasis. Gestalt therapy theory suggests that people make contact (that is, meet needs) through a characteristic style of interacting with the environment. Holland identifies six personality types in his theory and asserts that…

Trust in organizations — organizational, intergroup, and value research perspective

Directory of Open Access Journals (Sweden)

Kaltiainen J.

2018-03-01

Full Text Available In this overview article, we discuss the importance of trust for organizations by employing a multilevel and multidisciplinary perspective. We complement and contribute to the existing reviews by (1 considering trust not only within and between individuals and organizations, but also at the societal level, (2 bridging findings and literature from the fields of organizational, intergroup, and value research, and (3 summarizing recent research on the dynamics of trust and its development in organizations. Related to contemplating trust at various levels, we present multiple topics such as individual’s tendency to trust, employees’ trust in leaders, trust between groups with examples from organizational mergers and interethnic relations, and the relationship between trust and societies’ economic competitiveness. We conclude by summarizing recent organizational literature about the development of trust, transfers of trust towards different levels of leadership, and reciprocity in employees’ trust and fairness perceptions. In so doing, we contribute to the means to promote trust, active citizenship and socially sustainable growth of organizations and our societies.

Study on the fatigue crack initiation life under spherical contact

Energy Technology Data Exchange (ETDEWEB)

Cho, Yong Joo; Kim, Tae Wan [Busan National Univ., Busan (Korea, Republic of); Lee, Mun Ju [Samsung Electronics Co., Ltd., Suwon (Korea, Republic of)

2001-08-01

In case of contact fatigue, the accurate calculation of surface tractions and subsurface stress is essential to the prediction of crack initiation life. Surface tractions influencing shear stress amplitude have been obtained by contact analysis based on influence function. Subsurface stress has been obtained by using rectangular patch solutions. In this study, to simulate asperity contact under sliding condition, the tip of asperity was simulated by sphere and to calculate crack initiation life in the substrate, dislocation pileup theory was used.

Study on the fatigue crack initiation life under spherical contact

International Nuclear Information System (INIS)

Cho, Yong Joo; Kim, Tae Wan; Lee, Mun Ju

2001-01-01

In case of contact fatigue, the accurate calculation of surface tractions and subsurface stress is essential to the prediction of crack initiation life. Surface tractions influencing shear stress amplitude have been obtained by contact analysis based on influence function. Subsurface stress has been obtained by using rectangular patch solutions. In this study, to simulate asperity contact under sliding condition, the tip of asperity was simulated by sphere and to calculate crack initiation life in the substrate, dislocation pileup theory was used

Strengthening Purity: Moral Purity as a Mediator of Direct and Extended Cross-Group Friendships on Sexual Prejudice.

Science.gov (United States)

Vezzali, Loris; Brambilla, Marco; Giovannini, Dino; Paolo Colucci, Francesco

2017-01-01

The present research investigated whether enhanced perceptions of moral purity drive the effects of intergroup cross-group friendships on the intentions to interact with homosexuals. High-school students (N = 639) reported their direct and extended cross-group friendships with homosexuals as well as their beliefs regarding the moral character of the sexual minority. Participants further reported their desire to interact with homosexuals in the future. Results showed that both face-to-face encounters and extended contact with homosexuals increased their perceived moral purity, which in turn fostered more positive behavioral intentions. Results further revealed the specific role of moral purity in this sense, as differential perceptions along other moral domains (autonomy and community) had no mediation effects on behavioral tendencies toward homosexuals. The importance of these findings for improving intergroup relations is discussed, together with the importance of integrating research on intergroup contact and morality.

Taking one for the team: Physiological trajectories of painful intergroup retaliation.

Science.gov (United States)

Niedbala, Elizabeth M; Hohman, Zachary P; Harris, Breanna N; Abide, Alexandra C

2018-06-13

Retaliating against a threatening outgroup offers group members specific rewards, such as restored group esteem, a reduction in anger, and a sense of gratification. Because retaliation is rewarding, group members may appraise an attack on the outgroup to be beneficial, even if it feels physically painful. We hypothesized that group members would be more willing to endure pain to retaliate against a threatening outgroup, and that appraising the painful retaliation as rewarding would down-regulate their physiological stress response to pain. Participants were manipulated to feel threatened by a rival group and then completed the cold-pressor. During the cold-pressor, participants either retaliated against the outgroup or not. Results showed that retaliation inhibited physiological responses to pain, alleviated intergroup anger, and felt less aversive. We propose that these responses are caused by a cognitive reappraisal of pain, where painful retaliation is expected to be rewarding instead of threatening. Copyright © 2017. Published by Elsevier Inc.

Group-level competition influences urinary steroid hormones among wild red-tailed monkeys, indicating energetic costs.

Science.gov (United States)

Jaeggi, Adrian V; Trumble, Benjamin C; Brown, Michelle

2018-04-10

Various theories emphasize that intergroup competition should affect intragroup cooperation and social relationships, especially if the cost of intergroup competition outweighs that of intragroup competition. This cost of intergroup competition may be quantified by changes in physiological status, such as in the steroid hormones cortisol (C) and testosterone (T), which rise or are depressed during periods of energetic stress, respectively. Here we tested for changes in urinary C and T after intergroup encounters (IGEs) among wild red-tailed monkeys (Cercopithecus ascanius), a species that experiences frequent intergroup feeding competition, at the Ngogo station in Kibale National Park, Uganda. We assayed 108 urine samples, of which 36 were collected after IGEs, from 23 individuals in four social groups. Bayesian multilevel models controlling for various confounds revealed that IGEs increased C and decreased T relative to baseline, consistent with an energetic cost to IGEs. The C change was more apparent in samples collected early after IGEs, suggesting an anticipatory increase, whereas the T change was stronger in later samples, suggesting sustained energetic trade-offs. Hormone responses were not affected by the IGE outcome. This cost to intergroup competition, together with little evidence for intragroup competition in redtails and other guenons, establishes an interesting test case for theories emphasizing the effect of intergroup competition on intragroup cooperation. © 2018 Wiley Periodicals, Inc.

Dynamic frictional contact for elastic viscoplastic material

Directory of Open Access Journals (Sweden)

Kenneth L. Kuttler

2007-05-01

Full Text Available Using a general theory for evolution inclusions, existence and uniqueness theorems are obtained for weak solutions to a frictional dynamic contact problem for elastic visco-plastic material. An existence theorem in the case where the friction coefficient is discontinuous is also presented.

Social identity as both cause and effect : The development of group identification in response to anticipated and actual changes in the intergroup status hierarchy

NARCIS (Netherlands)

Doosje, B; Spears, R; Ellemers, N

This study investigates how in-group identification develops during group interaction and forms a dynamic input and output that changes over time. Phase I of the study shows how initial level of identification in combination with anticipated changes in the intergroup status hierarchy, predicts

Contact mechanical analysis of O-ring stresses

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyung Kyu

2007-02-15

The purpose of this project is to develop the approximate solutions of contact traction and internal stress of an O-ring by using a two dimensional elasticity for enhancing the design and failure prediction technology. Investigated were the applicability of Lindley's formulae of contact force prediction and the Hertz theory. Three cases of O-ring installation were considered. The approximate solution of contact tractions and internal stresses of each case were derived. The key results are summarized as follows: 1. It is verified that Lindley's formulae predicts the relationship between the fractional compression and contact force. 2. In the case of Case I, II and III without internal pressure, it is found that a function form of the contact traction is the Hertzian. So it is possible to express the traction with a Hertzian form and correction factors. 3. The internal stresses are derived in the case of the Hertzian traction profile. The stresses at the center of O-ring show a satisfactory result when compared with the finite element result.

Contact Binaries on Their Way Towards Merging

Science.gov (United States)

Gazeas, K.

2015-07-01

Contact binaries are the most frequently observed type of eclipsing star system. They are small, cool, low-mass binaries belonging to a relatively old stellar population. They follow certain empirical relationships that closely connect a number of physical parameters with each other, largely because of constraints coming from the Roche geometry. As a result, contact binaries provide an excellent test of stellar evolution, specifically for stellar merger scenarios. Observing campaigns by many authors have led to the cataloging of thousands of contact binaries and enabled statistical studies of many of their properties. A large number of contact binaries have been found to exhibit extraordinary behavior, requiring follow-up observations to study their peculiarities in detail. For example, a doubly-eclipsing quadruple system consisting of a contact binary and a detached binary is a highly constrained system offering an excellent laboratory to test evolutionary theories for binaries. A new observing project was initiated at the University of Athens in 2012 in order to investigate the possible lower limit for the orbital period of binary systems before coalescence, prior to merging.

Adolescent Peer Relations and Socioemotional Development in Latin America: Translating International Theory into Local Research.

Science.gov (United States)

Berger, Christian; Lisboa, Carolina; Cuadros, Olga; de Tezanos-Pinto, Pablo

2016-06-01

Peer relations constitute a main developmental context for adolescents. Peers offer an instance for identity definition and set the norms of acceptable and valued characteristics, behaviors, and attitudes, representing a societal model that allows and restrains avenues for adolescents' socioemotional development. The present article departs from these considerations to review research on adolescents' peer relations in Latin America from a socioemotional perspective. First, approaches to adolescence are discussed, with a main focus on attachment and identity theories, based on a bioecological framework. Then, a review of research in Latin America on friendships, school climate, and intergroup relations is presented. The discussion addresses the tension between theories and evidence generated in developed societies and highlights the particularities of Latin American youth, stressing the need for collecting local data. © 2016 Wiley Periodicals, Inc.

Modular invariance, chiral anomalies and contact terms

International Nuclear Information System (INIS)

Kutasov, D.

1988-03-01

The chiral anomaly in heterotic strings with full and partial modular invariance in D=2n+2 dimensions is calculated. The boundary terms which were present in previous calculations are shown to be cancelled in the modular invariant case by contact terms, which can be obtained by an appropriate analytic continuation. The relation to the low energy field theory is explained. In theories with partial modular invariance, an expression for the anomaly is obtained and shown to be non zero in general. (author)

The Influence of Personal and Collective Self-Esteem on the Interpersonal and Inter-group Evaluations of Japanese University Students

OpenAIRE

Brown, R. A.

2007-01-01

A sample of 236 Japanese college students evaluated themselves, two in-groups, and two outgroups,on five positive and five negative traits. They also completed the Rosenberg Self-Esteem Scaleand two subscales of the Luhtanen & Crocker Collective Self-Esteem Scale. The results revealed thatthe personal and collective self-esteem of Japanese college students is unaffected by perceptions of interpersonal or inter-group superiority or inferiority. It is therefore inferred that personal or group e...

Computing Tutte polynomials of contact networks in classrooms

Science.gov (United States)

Hincapié, Doracelly; Ospina, Juan

2013-05-01

Objective: The topological complexity of contact networks in classrooms and the potential transmission of an infectious disease were analyzed by sex and age. Methods: The Tutte polynomials, some topological properties and the number of spanning trees were used to algebraically compute the topological complexity. Computations were made with the Maple package GraphTheory. Published data of mutually reported social contacts within a classroom taken from primary school, consisting of children in the age ranges of 4-5, 7-8 and 10-11, were used. Results: The algebraic complexity of the Tutte polynomial and the probability of disease transmission increases with age. The contact networks are not bipartite graphs, gender segregation was observed especially in younger children. Conclusion: Tutte polynomials are tools to understand the topology of the contact networks and to derive numerical indexes of such topologies. It is possible to establish relationships between the Tutte polynomial of a given contact network and the potential transmission of an infectious disease within such network

Factors influencing accruement of contact hours for nurses.

Science.gov (United States)

Kubsch, Sylvia; Henniges, Amy; Lorenzoni, Nancy; Eckardt, Sally; Oleniczak, Sandra

2003-01-01

A decline in attendance at continuing education (CE) in nursing activities was observed in a Midwest state where CE attendance is not required. The purpose of this research study was to identify the effect of attitude, extrinsic and intrinsic reinforcement, and deterrents on contact hour accrual. A convenience sample of 282 registered nurses was surveyed using a researcher-constructed instrument determined to be valid and reliable. Registered nurses earning 0 to 15 contact hours annually reported accruing fewer contact hours in 1999 than in an average year. Registered nurses who earned 16 to 45+ contact hours annually reported earning more contact hours in 1999 than in an average year. Intrinsic reinforcement was found to be a significant motivator (r [257] = .242; p Operant Conditioning Theory has use in explaining registered nurse attendance at CE activities. CE planners should consider placing more emphasis on intrinsic rather than extrinsic reinforcement to encourage staff to attend CE activities.

Moving contact lines on vibrating surfaces

Science.gov (United States)

Solomenko, Zlatko; Spelt, Peter; Scott, Julian

2017-11-01

Large-scale simulations of flows with moving contact lines for realistic conditions generally requires a subgrid scale model (analyses based on matched asymptotics) to account for the unresolved part of the flow, given the large range of length scales involved near contact lines. Existing models for the interface shape in the contact-line region are primarily for steady flows on homogeneous substrates, with encouraging results in 3D simulations. Introduction of complexities would require further investigation of the contact-line region, however. Here we study flows with moving contact lines on planar substrates subject to vibrations, with applications in controlling wetting/dewetting. The challenge here is to determine the change in interface shape near contact lines due to vibrations. To develop further insight, 2D direct numerical simulations (wherein the flow is resolved down to an imposed slip length) have been performed to enable comparison with asymptotic theory, which is also developed further. Perspectives will also be presented on the final objective of the work, which is to develop a subgrid scale model that can be utilized in large-scale simulations. The authors gratefully acknowledge the ANR for financial support (ANR-15-CE08-0031) and the meso-centre FLMSN for use of computational resources. This work was Granted access to the HPC resources of CINES under the allocation A0012B06893 made by GENCI.

Constructal Optimization of Top Contact Metallization of a Photovoltaic Solar Cell

OpenAIRE

Bhakta, Aditya; Bandyopadhyay, Santanu

2010-01-01

A top contact metallization of a photovoltaic solar cell collects the current generated by incident solar radiation. Several power-loss mechanisms are associated with the current flow through the front contact grid. The design of the top metal contact grid is one of the most important areas of efficient photovoltaic solar cell design. In this paper, an approach based on the constructal theory is proposed to design the grid pattern in a photovoltaic solar cell, minimizing total resistive losse...

The ethnic composition of the neighbourhood and ethnic minorities' social contacts: three unresolved issues

OpenAIRE

Flap, H.D.; Dagevos, J.J.; Vervoort, M.

2010-01-01

It is frequently supposed that the ethnic composition of a neighbourhood affects ethnic minorities’ social contacts with natives, co-ethnics and other ethnic minorities. Research to date, however, falls short in several ways. First of all, previous studies often did not consider social contacts with co-ethnics and other ethnic minorities. Second, although different mechanisms (i.e. meeting opportunities, ethnic competition theory, ‘third parties’ and constrict theory) point to different dimen...

Dynamic contact with Signorini's condition and slip rate dependent friction

Directory of Open Access Journals (Sweden)

Kenneth Kuttler

2004-06-01

Full Text Available Existence of a weak solution for the problem of dynamic frictional contact between a viscoelastic body and a rigid foundation is established. Contact is modelled with the Signorini condition. Friction is described by a slip rate dependent friction coefficient and a nonlocal and regularized contact stress. The existence in the case of a friction coefficient that is a graph, which describes the jump from static to dynamic friction, is established, too. The proofs employ the theory of set-valued pseudomonotone operators applied to approximate problems and a priori estimates.

Mechanical deformation of atomic-scale metallic contacts: Structure and mechanisms

DEFF Research Database (Denmark)

Sørensen, Mads Reinholdt; Brandbyge, Mads; Jacobsen, Karsten Wedel

1998-01-01

We have simulated the mechanical deformation of atomic-scale metallic contacts under tensile strain using molecular dynamics and effective medium theory potentials. The evolution of the structure of the contacts and the underlying deformation mechanisms are described along with the calculated......, but vacancies can be permanently present. The transition states and energies for slip mechanisms have been determined using the nudged elastic band method, and we find a size-dependent crossover from a dislocation-mediated slip to a homogeneous slip when the contact diameter becomes less than a few nm. We show...

Contact interactions of closed superstrings

International Nuclear Information System (INIS)

Greensite, J.

1987-07-01

It is shown that closed light-cone superstring field theory, which is presently formulated with only cubic interaction terms, does not have a stable ground state, and that the global supersymmetry algebra is violated at second order in the coupling. Local contact interactions, of quartic (and possibly higher) order in the string fields, must be added to the light-cone Hamiltonian to restore supersymmetry and vacuum stability. (orig.)

The Josephson effect in atomic contacts

International Nuclear Information System (INIS)

Chauvin, M.

2005-11-01

The Josephson effect appears when a weak-link establishes phase coherence between two superconductors. A unifying theory of this effect emerged in the 90's within the framework of mesoscopic physics. Based on two cornerstone concepts, conduction channels and Andreev reflection, it predicts the current-phase relation for the most basic weak-link: a single conduction channel of arbitrary transmission. This thesis illustrates this mesoscopic point of view with experiments on superconducting atomic size contacts. In particular, we have focused on the supercurrent peak around zero voltage, put into evidence the ac Josephson currents in a contact under constant bias voltage (Shapiro resonances and photon assisted multiple Andreev reflections), and performed direct measurements of the current-phase relation. (author)

Validation of the Croatian Version of the Social Self-Esteem Scale

OpenAIRE

Margareta Jelić

2009-01-01

Within the frame of Social Identity Theory (SIT) self-esteem was given a central role in explaining intergroup discrimination. Furthermore, SIT emphasized the difference between personal and social identity and thus tried to avoid explaining group process and intergroup relations in terms of personal characteristics. However, social identity theory hypotheses are largely tested using measures of personal self-esteem due to the lack of social self-esteem measures. The Collective Self-Esteem Sc...

Does Identification With Rwanda Increase Reconciliation Sentiments Between Genocide Survivors and Non-Victims? The Mediating Roles of Perceived Intergroup Similarity and Self-Esteem During Commemorations

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Clémentine Kanazayire

2014-12-01

Full Text Available A questionnaire survey (N = 247 investigated the influence of identification with the Rwandan nation on reconciliation sentiments between members of the survivor and of the non-victim groups of the 1994 genocide in Rwanda. Results showed that, whereas the two groups did not differ in their level of identification with the nation, members of the non-victim group were more willing to reconcile than members of the survivor group. Perceived intergroup similarity mediated the effect of national identification on reconciliation sentiment for both groups, but this effect was stronger among non-victims. Finally, self-esteem during commemorations also mediated this effect, but only among non-victims. We discuss the importance of people’s motivation to reconcile with out-group members in post-genocidal contexts in light of the common in-group identity model (Gaertner & Dovidio, 2000 as well as the needs-based model of intergroup reconciliation (Nadler & Schnabel, 2008.

Measurement of Critical Contact Angle in a Microgravity Space Experiment

Science.gov (United States)

Concus, P.; Finn, R.; Weislogel, M.

1998-01-01

Mathematical theory predicts that small changes in container shape or in contact angle can give rise to large shifts of liquid in a microgravity environment. This phenomenon was investigated in the Interface Configuration Experiment on board the USMT,2 Space Shuttle flight. The experiment's "double proboscis" containers were designed to strike a balance between conflicting requirements of sizable volume of liquid shift (for ease of observation) and abruptness of the shift (for accurate determination of critical contact angle). The experimental results support the classical concept of macroscopic contact angle and demonstrate the role of hysteresis in impeding orientation toward equilibrium.

The Second Annual Student Scientific-Practical Conference in memory of M.Y. Kondratyev “Social Psychology: Issues of Theory and Practice”

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Babanin P.A.

2017-07-01

Full Text Available The present report contains the report on the work of the Second Annual Student Scientific-Practical Conference in Memory of M.Y. Kondratyev «Social Psychology: Issues of Theory and Practice». The conference was attended by the undergraduate and graduate students of MSUPE who submitted the reports, which reflected modern trends in the study of socialization of the individual, optimization of motivation in learning and professional activity, harmonization of interpersonal and intergroup relations in various spheres of life of a modern man.

The influence of discrimination and fairness on collective self-esteem.

Science.gov (United States)

Scheepers, Daan; Spears, Russell; Manstead, Antony S R; Doosje, Bertjan

2009-04-01

This article examines the influence of discrimination and fairness on collective self-esteem. Whereas social identity theory's self-esteem hypothesis emphasizes that discrimination can enhance self-esteem, the authors contend that this self-esteem advantage will actually reverse when groups are primed with the idea of engaging in a fair intergroup competition. They measured (Study 1) and manipulated (Study 2) discrimination and fairness in real (Study 1) and minimal (Study 2) groups, after which they manipulated the presence of an intergroup competition in both studies. Collective self-esteem served as the main dependent measure. Results indicated that when an intergroup competition was present or impending, previously expressed fairness (or less discrimination) was positively related to self-esteem, whereas discrimination was positively related to collective self-esteem in the absence of an intergroup competition. Results are discussed in terms of social identity theory and the importance of the broader social context for examining the relationship between discrimination and self-esteem.

Effects of internal friction on contact formation dynamics of polymer chain

Science.gov (United States)

Bian, Yukun; Li, Peng; Zhao, Nanrong

2018-04-01

A theoretical framework is presented to study the contact formation dynamics of polymer chains, in accompany with an electron-transfer quenching. Based on a non-Markovian Smoluchowski equation supplemented with an exponential sink term, we derive the mean time of contact formation under Wilemski-Fixman approximation. Our particular attentions are paid to the effect of internal friction. We find out that internal friction induces a novel fractional viscosity dependence, which will become more remarkable as internal friction increases. Furthermore, we clarify that internal friction inevitably promotes a diffusion-controlled mechanism by slowing the chain relaxation. Finally, we apply our theory to rationalise the experimental investigation for contact formation of a single-stranded DNA. The theoretical results can reproduce the experimental data very well with quite reasonable estimation for the intrinsic parameters. Such good agreements clearly demonstrate the validity of our theory which has appropriately addressed the very role of internal friction to the relevant dynamics.

Social contacts of older people in 27 European Countries : The role of welfare spending and economic inequality

NARCIS (Netherlands)

Ellwardt, Lea; Peter, S; Praeg, Patrick; Steverink, Nardi

Social contacts of older people have consistently been associated with good health and longevity. The extent of individual social contacts, however, varies considerably between countries. We study why countries differ in amounts of social contacts of older adults. Using theory on income inequality

Contact of a spherical probe with a stretched rubber substrate

Science.gov (United States)

Frétigny, Christian; Chateauminois, Antoine

2017-07-01

We report on a theoretical and experimental investigation of the normal contact of stretched neo-Hookean substrates with rigid spherical probes. Starting from a published formulation of surface Green's function for incremental displacements on a prestretched, neo-Hookean, substrate [J. Mech. Phys. Solids 56, 2957 (2008), 10.1016/j.jmps.2008.07.002], a model is derived for both adhesive and nonadhesive contacts. The shape of the elliptical contact area together with the contact load and the contact stiffness are predicted as a function of the in-plane stretch ratios λx and λy of the substrate. The validity of this model is assessed by contact experiments carried out using an uniaxally stretched silicone rubber. For stretch ratio below about 1.25, a good agreement is observed between theory and experiments. Above this threshold, some deviations from the theoretical predictions are induced as a result of the departure of the mechanical response of the silicone rubber from the neo-Hokeean description embedded in the model.

Contact Angle and Adhesion Dynamics and Hysteresis on Molecularly Smooth Chemically Homogeneous Surfaces.

Science.gov (United States)

Chen, Szu-Ying; Kaufman, Yair; Schrader, Alex M; Seo, Dongjin; Lee, Dong Woog; Page, Steven H; Koenig, Peter H; Isaacs, Sandra; Gizaw, Yonas; Israelachvili, Jacob N

2017-09-26

Measuring truly equilibrium adhesion energies or contact angles to obtain the thermodynamic values is experimentally difficult because it requires loading/unloading or advancing/receding boundaries to be measured at rates that can be slower than 1 nm/s. We have measured advancing-receding contact angles and loading-unloading adhesion energies for various systems and geometries involving molecularly smooth and chemically homogeneous surfaces moving at different but steady velocities in both directions, ±V, focusing on the thermodynamic limit of ±V → 0. We have used the Bell Theory (1978) to derive expressions for the dynamic (velocity-dependent) adhesion energies and contact angles suitable for both (i) dynamic adhesion measurements using the classic Johnson-Kendall-Roberts (JKR, 1971) theory of "contact mechanics" and (ii) dynamic contact angle hysteresis measurements of both rolling droplets and syringe-controlled (sessile) droplets on various surfaces. We present our results for systems that exhibited both steady and varying velocities from V ≈ 10 mm/s to 1 nm/s, where in all cases but one, the advancing (V > 0) and receding (V contact angles converged toward the same theoretical (thermodynamic) values as V → 0. Our equations for the dynamic contact angles are similar to the classic equations of Blake & Haynes (1969) and fitted the experimental adhesion data equally well over the range of velocities studied, although with somewhat different fitting parameters for the characteristic molecular length/dimension or area and characteristic bond formation/rupture lifetime or velocity. Our theoretical and experimental methods and results unify previous kinetic theories of adhesion and contact angle hysteresis and offer new experimental methods for testing kinetic models in the thermodynamic, quasi-static, limit. Our analyses are limited to kinetic effects only, and we conclude that hydrodynamic, i.e., viscous, and inertial effects do not play a role at the

String theory in four dimensions

International Nuclear Information System (INIS)

Dine, M.

1988-01-01

A representative sample of current ideas about how one might develop a string phenomenology is presented. Some of the obstacles which lie in between string theory and contact with experiment are described. It is hoped that this volume will provide the reader with ways of thinking about string theory in four dimensions and provide tools for asking questions about string theory and ordinary physics. 102 refs

Diminution of contact angle hysteresis under the influence of an oscillating force.

Science.gov (United States)

Manor, Ofer

2014-06-17

We suggest a simple quantitative model for the diminution of contact angle hysteresis under the influence of an oscillatory force invoked by thermal fluctuations, substrate vibrations, acoustic waves, or oscillating electric fields. Employing force balance rather than the usual description of contact angle hysteresis in terms of Gibbs energy, we highlight that a wetting system, such as a sessile drop or a bubble adhered to a solid substrate, appears at long times to be partially or fully independent of contact angle hysteresis and thus independent of static friction forces, as a result of contact line pinning. We verify this theory by studying several well-known experimental observations such as the approach of an arbitrary contact angle toward the Young contact angle and the apparent decrease (or increase) in an advancing (or a receding) contact angle under the influence of an external oscillating force.

Assessing an Adaptive Cycle in a Social System under External Pressure to Change: the Importance of Intergroup Relations in Recreational Fisheries Governance

Directory of Open Access Journals (Sweden)

Katrin Daedlow

2011-06-01

Full Text Available The adaptive cycle constitutes a heuristic originally used to interpret the dynamics of complex ecosystems in response to disturbance and change. It is assumed that socially constructed governance systems go through similar phases (K, Ω [omega], α [alpha], r as evident in ecological adaptive cycles. Two key dimensions of change shaping the four phases of an adaptive cycle are the degree of connectedness and the range of potential in the system. Our purpose was to quantitatively assess the four phases of the adaptive cycle in a social system by measuring the potential and connectedness dimensions and their different levels in each of the four phases. We assessed these dimensions using quantitative data from content analysis of magazine articles describing the transition process of East German recreational fisheries governance after the fall of the Berlin Wall in 1989. This process was characterized by the discussion of two governance alternatives amendable for implementation: a central East German and a decentralized West German approach. Contrary to assumptions in the adaptive cycle heuristic, we were unable to identify the four phases of the adaptive cycle in our governance system based on quantitatively assessed levels of connectedness and potential alone. However, the insertion of in-group (East Germans and out-group (West Germans dimensions representing the two governance alternatives in our analysis enabled us to identify the specific time frames for all four phases of the adaptive cycle on a monthly basis. These findings suggest that an unmodified "figure-eight model" of the adaptive cycle may not necessarily hold in social systems. Inclusion of disciplinary theories such as intergroup relation theory will help in understanding adaptation processes in social systems.

An alternative to FASTSIM for tangential solution of the wheel-rail contact

Science.gov (United States)

Sichani, Matin Sh.; Enblom, Roger; Berg, Mats

2016-06-01

In most rail vehicle dynamics simulation packages, tangential solution of the wheel-rail contact is gained by means of Kalker's FASTSIM algorithm. While 5-25% error is expected for creep force estimation, the errors of shear stress distribution, needed for wheel-rail damage analysis, may rise above 30% due to the parabolic traction bound. Therefore, a novel algorithm named FaStrip is proposed as an alternative to FASTSIM. It is based on the strip theory which extends the two-dimensional rolling contact solution to three-dimensional contacts. To form FaStrip, the original strip theory is amended to obtain accurate estimations for any contact ellipse size and it is combined by a numerical algorithm to handle spin. The comparison between the two algorithms shows that using FaStrip improves the accuracy of the estimated shear stress distribution and the creep force estimation in all studied cases. In combined lateral creepage and spin cases, for instance, the error in force estimation reduces from 18% to less than 2%. The estimation of the slip velocities in the slip zone, needed for wear analysis, is also studied. Since FaStrip is as fast as FASTSIM, it can be an alternative for tangential solution of the wheel-rail contact in simulation packages.

THE CONTROL VARIATIONAL METHOD FOR ELASTIC CONTACT PROBLEMS

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Mircea Sofonea

2010-07-01

Full Text Available We consider a multivalued equation of the form Ay + F(y = fin a real Hilbert space, where A is a linear operator and F represents the (Clarke subdifferential of some function. We prove existence and uniqueness results of the solution by using the control variational method. The main idea in this method is to minimize the energy functional associated to the nonlinear equation by arguments of optimal control theory. Then we consider a general mathematical model describing the contact between a linearly elastic body and an obstacle which leads to a variational formulation as above, for the displacement field. We apply the abstract existence and uniqueness results to prove the unique weak solvability of the corresponding contact problem. Finally, we present examples of contact and friction laws for which our results work.

Interracial roommate relationships: an experimental field test of the contact hypothesis.

Science.gov (United States)

Shook, Natalie J; Fazio, Russell H

2008-07-01

This study investigated how automatically activated racial attitudes are affected by relatively long-term interracial relationships. A natural field experiment was conducted in a college dormitory system. Participants were White freshmen who had been randomly assigned to either a White or an African American roommate. Students participated in two sessions during the first 2 and last 2 weeks of their first quarter on campus. During these sessions, they answered questions about their satisfaction and involvement with their roommates and completed an inventory of intergroup anxiety and an implicit measure of racial attitudes. Participants in interracial rooms reported less satisfaction and less involvement with their roommates than did participants in same-race rooms. However, automatically activated racial attitudes and intergroup anxiety improved over time among students in interracial rooms, but not among students in same-race rooms. Thus, the results suggest that interracial roommate relationships, although generally less satisfying and involving than same-race roommate relationships, do produce benefits.

Learning to push and learning to move: The adaptive control of contact forces

Directory of Open Access Journals (Sweden)

Maura eCasadio

2015-11-01

Full Text Available To be successful at manipulating objects one needs to apply simultaneously well controlled movements and contact forces. We present a computational theory of how the brain may successfully generate a vast spectrum of interactive behaviors by combining two independent processes. One process is competent to control movements in free space and the other is competent to control contact forces against rigid constraints. Free space and rigid constraints are singularities at the boundaries of a continuum of mechanical impedance. Within this continuum, forces and motions occur in compatible pairs connected by the equations of Newtonian dynamics. The force applied to an object determines its motion. Conversely, inverse dynamics determine a unique force trajectory from a movement trajectory. In this perspective, we describe motor learning as a process leading to the discovery of compatible force/motion pairs. The learned compatible pairs constitute a local representation of the environment's mechanics. Experiments on force field adaptation have already provided us with evidence that the brain is able to predict and compensate the forces encountered when one is attempting to generate a motion. Here, we tested the theory in the dual case, i.e. when one attempts at applying a desired contact force against a simulated rigid surface. If the surface becomes unexpectedly compliant, the contact point moves as a function of the applied force and this causes the applied force to deviate from its desired value. We found that, through repeated attempts at generating the desired contact force, subjects discovered the unique compatible hand motion. When, after learning, the rigid contact was unexpectedly restored, subjects displayed after effects of learning, consistent with the concurrent operation of a motion control system and a force control system. Together, theory and experiment support a new and broader view of modularity in the coordinated control of forces and

Integrating water exclusion theory into βcontacts to predict binding free energy changes and binding hot spots

Science.gov (United States)

2014-01-01

Background Binding free energy and binding hot spots at protein-protein interfaces are two important research areas for understanding protein interactions. Computational methods have been developed previously for accurate prediction of binding free energy change upon mutation for interfacial residues. However, a large number of interrupted and unimportant atomic contacts are used in the training phase which caused accuracy loss. Results This work proposes a new method, βACV ASA , to predict the change of binding free energy after alanine mutations. βACV ASA integrates accessible surface area (ASA) and our newly defined β contacts together into an atomic contact vector (ACV). A β contact between two atoms is a direct contact without being interrupted by any other atom between them. A β contact’s potential contribution to protein binding is also supposed to be inversely proportional to its ASA to follow the water exclusion hypothesis of binding hot spots. Tested on a dataset of 396 alanine mutations, our method is found to be superior in classification performance to many other methods, including Robetta, FoldX, HotPOINT, an ACV method of β contacts without ASA integration, and ACV ASA methods (similar to βACV ASA but based on distance-cutoff contacts). Based on our data analysis and results, we can draw conclusions that: (i) our method is powerful in the prediction of binding free energy change after alanine mutation; (ii) β contacts are better than distance-cutoff contacts for modeling the well-organized protein-binding interfaces; (iii) β contacts usually are only a small fraction number of the distance-based contacts; and (iv) water exclusion is a necessary condition for a residue to become a binding hot spot. Conclusions βACV ASA is designed using the advantages of both β contacts and water exclusion. It is an excellent tool to predict binding free energy changes and binding hot spots after alanine mutation. PMID:24568581

Static friction of stainless steel wire rope–rubber contacts.

NARCIS (Netherlands)

Loeve, A.J.; Krijger, T.; Mugge, W.; Breedveld, P.; Dodou, D.; Dankelman, J.

2014-01-01

Little is known about static friction of stainless-steel wire ropes ('cables') in contact with soft rubbers, an interface of potential importance for rigidifiable medical instruments. Although friction theories imply that the size and profile of the cables affect static friction, there are no

The cortisol response to anticipated intergroup interactions predicts self-reported prejudice.

Science.gov (United States)

Bijleveld, Erik; Scheepers, Daan; Ellemers, Naomi

2012-01-01

While prejudice has often been shown to be rooted in experiences of threat, the biological underpinnings of this threat-prejudice association have received less research attention. The present experiment aims to test whether activations of the hypothalamus-pituitary-adrenal (HPA) axis, due to anticipated interactions with out-group members, predict self-reported prejudice. Moreover, we explore potential moderators of this relationship (i.e., interpersonal similarity; subtle vs. blatant prejudice). Participants anticipated an interaction with an out-group member who was similar or dissimilar to the self. To index HPA activation, cortisol responses to this event were measured. Then, subtle and blatant prejudices were measured via questionnaires. Findings indicated that only when people anticipated an interaction with an out-group member who was dissimilar to the self, their cortisol response to this event significantly predicted subtle (r = .50) and blatant (r = .53) prejudice. These findings indicate that prejudicial attitudes are linked to HPA-axis activity. Furthermore, when intergroup interactions are interpreted to be about individuals (and not so much about groups), experienced threat (or its biological substrate) is less likely to relate to prejudice. This conclusion is discussed in terms of recent insights from social neuroscience.

From natural to biomimetic: The superhydrophobicity and the contact time.

Science.gov (United States)

Liang, Yun-Hong; Peng, Jian; Li, Xiu-Juan; Xu, Jin-Kai; Zhang, Zhi-Hui; Ren, Lu-Quan

2016-08-01

The superhydrophobicities and the contact time of lotus leaf and reed leaf were investigated. The results indicated that both lotus leaf and reed leaf have good superhydrophobic properties, and the water contact time was 12.7 and 14.7 ms on the surface of lotus leaf and reed leaf, respectively. Surface structure plays a key role in the different contacting times. Homogeneous distribution of papillae on the surface of lotus leaf was more helpful to reduce the contact time than anisotropic groove-shape on the surface of reed leaf. Based on the bionics coupling theory, the bionics sample possessing similar lotus-leaf-like surface structure on the aluminum alloy was designed and fabricated successfully. The water contact angle was about 153 ± 2°, sliding angle less than 5°, and the water contact time was 13.4 ms on the surface of bionics sample, which presented excellent superhydrophobic property, and achieved the aim of bionic design. Microsc. Res. Tech. 79:712-720, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Occupational contact urticaria and protein contact dermatitis.

Science.gov (United States)

Doutre, Marie-Sylvie

2005-01-01

Irritant dermatitis and eczema are the most prevalent occupational skin diseases. Less common are immediate contact reactions such as contact urticaria and protein contact dermatitis. Occupational contact urticaria can be subdivided into two categories, immunological and non immunological. However, some agents can induce these two types of reactions. Contact urticaria to natural rubber latex is particularly frequent among health care personnel, but contact urticaria to a wide variety of other substances occurs in many other occupations. Among those at risk are cooks, bakers, butchers, restaurant personnel, veterinarians, hairdressers, florists, gardeners, and forestry workers. Protein contact dermatitis in some of these occupations is caused principally by proteins of animal or plant origin, especially among individuals with a history of atopic dermatitis. Diagnosis requires careful interrogation, clinical examination and skin tests (open tests and prick tests with immediate lecture) to identify a particular contact allergen.

Communal and Agentic Interpersonal and Intergroup Motives Predict Preferences for Status Versus Power.

Science.gov (United States)

Locke, Kenneth D; Heller, Sonja

2017-01-01

Seven studies involving 1,343 participants showed how circumplex models of social motives can help explain individual differences in preferences for status (having others' admiration) versus power (controlling valuable resources). Studies 1 to 3 and 7 concerned interpersonal motives in workplace contexts, and found that stronger communal motives (to have mutual trust, support, and cooperation) predicted being more attracted to status (but not power) and achieving more workplace status, while stronger agentic motives (to be firm, decisive, and influential) predicted being more attracted to and achieving more workplace power, and experiencing a stronger connection between workplace power and job satisfaction. Studies 4 to 6 found similar effects for intergroup motives: Stronger communal motives predicted wanting one's ingroup (e.g., country) to have status-but not power-relative to other groups. Finally, most people preferred status over power, and this was especially true for women, which was partially explained by women having stronger communal motives.

Diminishing parochialism in intergroup conflict by disrupting the right temporo-parietal junction.

Science.gov (United States)

Baumgartner, Thomas; Schiller, Bastian; Rieskamp, Jörg; Gianotti, Lorena R R; Knoch, Daria

2014-05-01

Individuals react to violation of social norms by outgroup members differently than to transgressions of those same norms by ingroup members: namely outgroup perpetrators are punished much more harshly than ingroup perpetrators. This parochial punishment pattern has been observed and extensively studied in social psychology and behavioral economics. Despite progress in recent years, however, little is known about the neural underpinnings of this intergroup bias. Here, we demonstrate by means of transcranial magnetic stimulation (TMS) that the transient disruption of the right, but not the left temporo-parietal junction (TPJ), reduces parochial punishment in a third-party punishment paradigm with real social groups. Moreover, we show that this observed TMS effect on parochial punishment is mediated by a classical punishment motive, i.e. retaliation. Finally, our data suggests that a change in perspective-taking might be the underlying mechanism that explains the impact of right TPJ disruption on retaliation motivation and parochial punishment. These findings provide the first causal evidence that the right TPJ plays a pivotal role in the implementation of parochial behaviors.

Universal contact of strongly interacting fermions at finite temperatures

Energy Technology Data Exchange (ETDEWEB)

Hu Hui; Liu Xiaji; Drummond, Peter D, E-mail: hhu@swin.edu.au, E-mail: xiajiliu@swin.edu.au, E-mail: pdrummond@swin.edu.au [ARC Centre of Excellence for Quantum-Atom Optics, Centre for Atom Optics and Ultrafast Spectroscopy, Swinburne University of Technology, Melbourne 3122 (Australia)

2011-03-15

The recently discovered universal thermodynamic behavior of dilute, strongly interacting Fermi gases also implies a universal structure in the many-body pair-correlation function at short distances, as quantified by the contact I. Here, we theoretically calculate the temperature dependence of this universal contact for a Fermi gas in free space and in a harmonic trap. At high temperatures above the Fermi degeneracy temperature, T{approx}>T{sub F}, we obtain a reliable non-perturbative quantum virial expansion up to third order. At low temperatures, we compare different approximate strong-coupling theories. These make different predictions, which need to be tested either by future experiments or by advanced quantum Monte Carlo simulations. We conjecture that in the universal unitarity limit, the contact or correlation decreases monotonically with increasing temperature, unless the temperature is significantly lower than the critical temperature, T<contact in either homogeneous or harmonically trapped Fermi gases.

Theory of the Andreev reflection and the density of states in proximity contact normal-superconducting infinite double-layer

International Nuclear Information System (INIS)

Nagato, Yasushi; Nagai, Katsuhiko

1993-01-01

Proximity contact N-S double-layer with infinite layer widths is studied in the clean limit. The finite reflection at the interface is taken into account. Starting from a recent theory of finite width double-layer by Ashida et al., the authors obtain explicit expressions for the quasi-classical Green's function which already satisfy the boundary condition and include no exploding terms at infinities. The self-consistent pair potentials are obtained numerically with sufficient accuracy. The Andreev reflection at the N-S interface is discussed on the basis of the self-consistent pair potential. It is shown that there exists a resonance state in a potential valley formed between the depressed pair potential and the partially reflecting interface, which leads to a peak of the Andreev reflection coefficient with the height unity slightly below the bulk superconductor energy gap. They also find general relationship between the Andreev reflection coefficient and the local density of states of the superconductor just at the interface

Molecular Theory and Simulation of Water-Oil Contacts

Science.gov (United States)

Tan, Liang

The statistical mechanical theory of hydrophobic interactions was initiated decades ago for purely repulsive hydrophobic species, in fact, originally for hard-sphere solutes in liquid water. Systems which treat only repulsive solute-water interactions obviously differ from the real world situation. The issue of the changes to be expected from inclusion of realistic attractive solute-water interactions has been of specific interest also for decades. We consider the local molecular field (LMF) theory for the effects of solute attractive forces on hydrophobic interactions. The principal result of LMF theory is outlined, then tested by obtaining radial distribution functions (rdfs) for Ar atoms in water, with and without attractive interactions distinguished by the Weeks-Chandler-Andersen (WCA) separation. Change from purely repulsive atomic solute interactions to include realistic attractive interactions substantially diminishes the strength of hydrophobic bonds. Since attractions make a big contribution to hydrophobic interactions, Pratt-Chandler theory, which did not include attractions, should not be naively compared to computer simulation results with general physical interactions, including attractions. Lack of general appreciation of this point has lead to mistaken comparisons throughout the history of this subject. The rdfs permit evaluation of osmotic second virial coefficients B2. Those B 2 are consistent with the conclusion that incorporation of attractive interactions leads to more positive (repulsive) values. In all cases here, B2 becomes more attractive with increasing temperature below T = 360K, the so-call inverse temperature behavior. In 2010, the Gulf of Mexico Macondo well (Deepwater Horizon) oil spill focused the attention of the world on water-oil phase equilibrium. In response to the disaster, chemical dispersants were applied to break oil slicks into droplets and thus to avoid large-scale fouling of beaches and to speed up biodegradation

Identifying barriers to and facilitators of tuberculosis contact investigation in Kampala, Uganda: a behavioral approach.

Science.gov (United States)

Ayakaka, Irene; Ackerman, Sara; Ggita, Joseph M; Kajubi, Phoebe; Dowdy, David; Haberer, Jessica E; Fair, Elizabeth; Hopewell, Philip; Handley, Margaret A; Cattamanchi, Adithya; Katamba, Achilles; Davis, J Lucian

2017-03-09

The World Health Organization recommends routine household tuberculosis contact investigation in high-burden countries but adoption has been limited. We sought to identify barriers to and facilitators of TB contact investigation during its introduction in Kampala, Uganda. We collected cross-sectional qualitative data through focus group discussions and interviews with stakeholders, addressing three core activities of contact investigation: arranging household screening visits through index TB patients, visiting households to screen contacts and refer them to clinics, and evaluating at-risk contacts coming to clinics. We analyzed the data using a validated theory of behavior change, the Capability, Opportunity, and Motivation determine Behavior (COM-B) model, and sought to identify targeted interventions using the related Behavior Change Wheel implementation framework. We led seven focus-group discussions with 61 health-care workers, two with 21 lay health workers (LHWs), and one with four household contacts of newly diagnosed TB patients. We, in addition, performed 32 interviews with household contacts from 14 households of newly diagnosed TB patients. Commonly noted barriers included stigma, limited knowledge about TB among contacts, insufficient time and space in clinics for counselling, mistrust of health-center staff among index patients and contacts, and high travel costs for LHWs and contacts. The most important facilitators identified were the personalized and enabling services provided by LHWs. We identified education, persuasion, enablement, modeling of health-positive behaviors, incentivization, and restructuring of the service environment as relevant intervention functions with potential to alleviate barriers to and enhance facilitators of TB contact investigation. The use of a behavioral theory and a validated implementation framework provided a comprehensive approach for systematically identifying barriers to and facilitators of TB contact

Transversity results and computations in symplectic field theory

International Nuclear Information System (INIS)

Fabert, Oliver

2008-01-01

Although the definition of symplectic field theory suggests that one has to count holomorphic curves in cylindrical manifolds R x V equipped with a cylindrical almost complex structure J, it is already well-known from Gromov-Witten theory that, due to the presence of multiply-covered curves, we in general cannot achieve transversality for all moduli spaces even for generic choices of J. In this thesis we treat the transversality problem of symplectic field theory in two important cases. In the first part of this thesis we are concerned with the rational symplectic field theory of Hamiltonian mapping tori, which is also called the Floer case. For this observe that in the general geometric setup for symplectic field theory, the contact manifolds can be replaced by mapping tori M φ of symplectic manifolds (M,ω M ) with symplectomorphisms φ. While the cylindrical contact homology of M φ is given by the Floer homologies of powers of φ, the other algebraic invariants of symplectic field theory for M φ provide natural generalizations of symplectic Floer homology. For symplectically aspherical M and Hamiltonian φ we study the moduli spaces of rational curves and prove a transversality result, which does not need the polyfold theory by Hofer, Wysocki and Zehnder and allows us to compute the full contact homology of M φ ≅ S 1 x M. The second part of this thesis is devoted to the branched covers of trivial cylinders over closed Reeb orbits, which are the trivial examples of punctured holomorphic curves studied in rational symplectic field theory. Since all moduli spaces of trivial curves with virtual dimension one cannot be regular, we use obstruction bundles in order to find compact perturbations making the Cauchy-Riemann operator transversal to the zero section and show that the algebraic count of elements in the resulting regular moduli spaces is zero. Once the analytical foundations of symplectic field theory are established, our result implies that the

Electric field effect on the critical current of SNS-contact

International Nuclear Information System (INIS)

Rakhmanov, A.L.; Rozhkov, A.V.

1995-01-01

Electric field effect on the SNS-contact critical current is investigated in the Ginzburg-Landau theory approximation. It is shown that the electric field may cause a notable increase of the contact critical current especially if the sample temperature is close to the temperature of a superconducting transition of T sc normal layer. Electric field effect is increased with the reduction of film thickness, but it can strong enough for thick films as well at temperature close to T sc . 11 refs.; 4 figs

Cold welding of organic light emitting diode: Interfacial and contact models

Directory of Open Access Journals (Sweden)

J. Asare

2016-06-01

Full Text Available This paper presents the results of an analytical and computational study of the contacts and interfacial fracture associated with the cold welding of Organic Light Emitting diodes (OLEDs. The effects of impurities (within the possible interfaces are explored for contacts and interfacial fracture between layers that are relevant to model OLEDs. The models are used to study the effects of adhesion, pressure, thin film layer thickness and dust particle modulus (between the contacting surfaces on contact profiles around impurities between cold-welded thin films. The lift-off stage of thin films (during cold welding is then modeled as an interfacial fracture process. A combination of adhesion and interfacial fracture theories is used to provide new insights for the design of improved contact and interfacial separation during cold welding. The implications of the results are discussed for the design and fabrication of cold welded OLED structures.

Theory and simulation of charge transfer through DNA - nanotube contacts

International Nuclear Information System (INIS)

Rink, Gunda; Kong Yong; Koslowski, Thorsten

2006-01-01

We address the problem of charge transfer between a single-stranded adenine oligomer and semiconducting boron nitride nanotubes from a theoretical and numerical perspective. The model structures have been motivated by computer simulations; sample geometries are used as the input of an electronic structure theory that is based upon an extended Su-Schrieffer-Heeger Hamiltonian. By analyzing the emerging potential energy surfaces, we obtain hole transfer rates via Marcus' theory of charge transfer. In the presence of nanotubes, these rates exceed those of isolated DNA single strands by a factor of up to 10 4 . This enhancement can be rationalized and quantified as a combination of a template effect and the participation of the tube within a superexchange mechanism

Multipoint contact modeling of nanoparticle manipulation on rough surface

Energy Technology Data Exchange (ETDEWEB)

Zakeri, M., E-mail: m.zakeri@tabrizu.ac.ir; Faraji, J.; Kharazmi, M. [University of Tabriz, School of Engineering Emerging Technologies (Iran, Islamic Republic of)

2016-12-15

In this paper, the atomic force microscopy (AFM)-based 2-D pushing of nano/microparticles investigated on rough substrate by assuming a multipoint contact model. First, a new contact model was extracted and presented based on the geometrical profiles of Rumpf, Rabinovich and George models and the contact mechanics theories of JKR and Schwartz, to model the adhesion forces and the deformations in the multipoint contact of rough surfaces. The geometry of a rough surface was defined by two main parameters of asperity height (size of roughness) and asperity wavelength (compactness of asperities distribution). Then, the dynamic behaviors of nano/microparticles with radiuses in range of 50–500 nm studied during their pushing on rough substrate with a hexagonal or square arrangement of asperities. Dynamic behavior of particles were simulated and compared by assuming multipoint and single-point contact schemes. The simulation results show that the assumption of multipoint contact has a considerable influence on determining the critical manipulation force. Additionally, the assumption of smooth surfaces or single-point contact leads to large error in the obtained results. According to the results of previous research, it anticipated that a particles with the radius less than about 550 nm start to slide on smooth substrate; but by using multipoint contact model, the predicted behavior changed, and particles with radii of smaller than 400 nm begin to slide on rough substrate for different height of asperities, at first.

The contact area and sliding friction in nanotribological systems

International Nuclear Information System (INIS)

Wolloch, M.

2014-01-01

Although friction, wear, and lubrication have been investigated for hundreds of years, many important questions in the field, now dubbed tribology, remain open. Two of these are the determination of the real area of contact and the direction dependence of friction forces on the nanoscale, which are investigated in this thesis. The invention of the atomic force microscope (AFM) in 1986 by Binnig , Quate, and Gerber was invaluable for the investigation of frictional forces on the atomic scale, giving a boost to the emerging field of nanotribology. While experimental AFM set-ups where quickly modeled with classical molecular dynamic (MD) simulations, the use of 'ab-initio' methods on tribological problems remained scarce until recently. In this thesis density functional theory (DFT) is used to develop parameter free methods in the field of nanotribology. Since the discovery that the apparent area of contact can be orders of magnitude larger than the true area of contact, the definition and determination of the latter has been an important topic of research. While classical contact mechanics provides satisfactory theories and results for various macroscopic systems, the application of these methods to atomistic systems is dubious, as the contacting bodies are not continuous at this length scale. We developed a parameter free approach to define and calculate the real area of contact between two bodies depending on distance. Strong relaxations at distinct distances, like the j ump to contact , which is often observed in AFM experiments, are used to define the onset of contact and Bader-s Quantum Theory of Atoms in Molecules is used to calculate the real area of contact at a given distance. Bader's method partitions the charge density ρ unambiguously into atoms, which theoretically fill all space and thus give non zero contact areas for all distances. It is therefore necessary to use a density cutoff ρ cut which assigns all regions in space where ρ < �

Multiloop integral system test (MIST): Final report, Inter-group comparisons

Energy Technology Data Exchange (ETDEWEB)

Gloudemans, J.R.

1989-07-01

The multiloop integral system test (MIST) was part of a multiphase program started in 1983 to address small-break loss-of-coolant accidents (SBLOCAs) specific to Babcock and Wilcox-designed plants. MIST was sponsored by the US Nuclear Regulatory Commission, the Babcock and Wilcox Owners Group, the Electric Power Research Institute, and Babcock and Wilcox. The unique features of the Babcock and Wilcox design, specifically the hot leg U-bends and steam generators, prevented the use of existing integral system data or existing integral system facilities to address the thermal-hydraulic SBLOCA questions. MIST and two other supporting facilities were specifically designed and constructed for this program, and an existing facility -- the once-through integral system (OTIS) -- was also used. Data from MIST and the other facilities will be used to benchmark the adequacy of system codes, such as RELAP5 and TRAC, for predicting abnormal plant transients. The individual tests are described in detail in Volumes 2 through 8 and Volume 11, and are summarized in Volume 1. Inter-group comparisons are addressed in this document, Volume 9. These comparisons are grouped as follows: mapping versus SBLOCA transients, SBLOCA, pump effects, and the effects of noncondensible gases. Appendix A provides an index and description of the microfiched plots for each test, which are enclosed with the corresponding Volumes 2 through 8. 147 figs., 5 tabs.

On SYM theory and all order bulk singularity structures of BPS strings in type II theory

Science.gov (United States)

Hatefi, Ehsan

2018-06-01

The complete forms of the S-matrix elements of a transverse scalar field, two world volume gauge fields, and a Potential Cn-1 Ramond-Ramond (RR) form field are investigated. In order to find an infinite number of t , s , (t + s + u)-channel bulk singularity structures of this particular mixed open-closed amplitude, we employ all the conformal field theory techniques to , exploring all the entire correlation functions and all order α‧ contact interactions to these supersymmetric Yang-Mills (SYM) couplings. Singularity and contact term comparisons with the other symmetric analysis, and are also carried out in detail. Various couplings from pull-Back of branes, Myers terms and several generalized Bianchi identities should be taken into account to be able to reconstruct all order α‧ bulk singularities of type IIB (IIA) superstring theory. Finally, we make a comment on how to derive without any ambiguity all order α‧ contact terms of this S-matrix which carry momentum of RR in transverse directions.

Psychological foundations of xenophilia: the role of major personality traits in predicting favorable attitudes toward cross-cultural contact and exploration.

Science.gov (United States)

Stürmer, Stefan; Benbow, Alison E F; Siem, Birte; Barth, Markus; Bodansky, Alexander N; Lotz-Schmitt, Katharina

2013-11-01

Building on an integration of research findings on intergroup behavior from multiple fields of scientific inquiry (biological and cultural paleoanthropology, social psychology), as well as research on the HEXACO personality framework (e.g., Ashton & Lee, 2007), 3 independent studies (total N = 1,007) were conducted to introduce and test a fresh personality perspective on human xenophilia. Even though the studies focused on different criteria (Study 1: favorable attitudes toward contact with immigrants, Study 2: habitual cross-cultural exploration, Study 3: favorable attitudes toward contact with indigenous people) and employed different operationalizations of major personality traits (the HEXACO Personality Inventory-Revised [HEXACO-PI-R], the 10-item Big Five Inventory [BFI-10]) results were remarkably similar. First, path analyses confirmed that major personality traits were significant and direct predictors of xenophilia that were independent of the contributions of individual differences commonly predicting xenophobic reactions across studies. Second, and in line with the authors' more specific hypotheses, hierarchical regression analyses also corroborated that individual differences in the levels of endeavor-related personality traits (i.e., eXtraversion, Openness, and Conscientiousness) had a substantially greater power in predicting individual differences in xenophilia than individual differences in levels of altruism/cooperation-related traits (i.e., Honesty-Humility, Emotionality, and Agreeableness). The implications of these findings for more general psychological theorizing on human sociality are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved

Molecular dynamics study of contact mechanics: contact area and interfacial separation from small to full contact

OpenAIRE

Yang, C.; Persson, B. N. J.

2007-01-01

We report a molecular dynamics study of the contact between a rigid solid with a randomly rough surface and an elastic block with a flat surface. We study the contact area and the interfacial separation from small contact (low load) to full contact (high load). For small load the contact area varies linearly with the load and the interfacial separation depends logarithmically on the load. For high load the contact area approaches to the nominal contact area (i.e., complete contact), and the i...

Optimal contact definition for reconstruction of Contact Maps

Directory of Open Access Journals (Sweden)

Stehr Henning

2010-05-01

Full Text Available Abstract Background Contact maps have been extensively used as a simplified representation of protein structures. They capture most important features of a protein's fold, being preferred by a number of researchers for the description and study of protein structures. Inspired by the model's simplicity many groups have dedicated a considerable amount of effort towards contact prediction as a proxy for protein structure prediction. However a contact map's biological interest is subject to the availability of reliable methods for the 3-dimensional reconstruction of the structure. Results We use an implementation of the well-known distance geometry protocol to build realistic protein 3-dimensional models from contact maps, performing an extensive exploration of many of the parameters involved in the reconstruction process. We try to address the questions: a to what accuracy does a contact map represent its corresponding 3D structure, b what is the best contact map representation with regard to reconstructability and c what is the effect of partial or inaccurate contact information on the 3D structure recovery. Our results suggest that contact maps derived from the application of a distance cutoff of 9 to 11Å around the Cβ atoms constitute the most accurate representation of the 3D structure. The reconstruction process does not provide a single solution to the problem but rather an ensemble of conformations that are within 2Å RMSD of the crystal structure and with lower values for the pairwise average ensemble RMSD. Interestingly it is still possible to recover a structure with partial contact information, although wrong contacts can lead to dramatic loss in reconstruction fidelity. Conclusions Thus contact maps represent a valid approximation to the structures with an accuracy comparable to that of experimental methods. The optimal contact definitions constitute key guidelines for methods based on contact maps such as structure prediction through

Interfacial waves generated by electrowetting-driven contact line motion

Science.gov (United States)

Ha, Jonghyun; Park, Jaebum; Kim, Yunhee; Shin, Bongsu; Bae, Jungmok; Kim, Ho-Young

2016-10-01

The contact angle of a liquid-fluid interface can be effectively modulated by the electrowetting-on-dielectric (EWOD) technology. Rapid movement of the contact line can be achieved by swift changes of voltage at the electrodes, which can give rise to interfacial waves under the strong influence of surface tension. Here we experimentally demonstrate EWOD-driven interfacial waves of overlapping liquids and compare their wavelength and decay length with the theoretical results obtained by a perturbation analysis. Our theory also allows us to predict the temporal evolution of the interfacial profiles in either rectangular or cylindrical containers, as driven by slipping contact lines. This work builds a theoretical framework to understand and predict the dynamics of capillary waves of a liquid-liquid interface driven by EWOD, which has practical implications on optofluidic devices used to guide light.

The Cortisol Response to Anticipated Intergroup Interactions Predicts Self-Reported Prejudice

Science.gov (United States)

Bijleveld, Erik; Scheepers, Daan; Ellemers, Naomi

2012-01-01

Objectives While prejudice has often been shown to be rooted in experiences of threat, the biological underpinnings of this threat–prejudice association have received less research attention. The present experiment aims to test whether activations of the hypothalamus-pituitary-adrenal (HPA) axis, due to anticipated interactions with out-group members, predict self-reported prejudice. Moreover, we explore potential moderators of this relationship (i.e., interpersonal similarity; subtle vs. blatant prejudice). Methodology/Principal findings Participants anticipated an interaction with an out-group member who was similar or dissimilar to the self. To index HPA activation, cortisol responses to this event were measured. Then, subtle and blatant prejudices were measured via questionnaires. Findings indicated that only when people anticipated an interaction with an out-group member who was dissimilar to the self, their cortisol response to this event significantly predicted subtle (r = .50) and blatant (r = .53) prejudice. Conclusions These findings indicate that prejudicial attitudes are linked to HPA-axis activity. Furthermore, when intergroup interactions are interpreted to be about individuals (and not so much about groups), experienced threat (or its biological substrate) is less likely to relate to prejudice. This conclusion is discussed in terms of recent insights from social neuroscience. PMID:22442709

Contact angle and local wetting at contact line.

Science.gov (United States)

Li, Ri; Shan, Yanguang

2012-11-06

This theoretical study was motivated by recent experiments and theoretical work that had suggested the dependence of the static contact angle on the local wetting at the triple-phase contact line. We revisit this topic because the static contact angle as a local wetting parameter is still not widely understood and clearly known. To further clarify the relationship of the static contact angle with wetting, two approaches are applied to derive a general equation for the static contact angle of a droplet on a composite surface composed of heterogeneous components. A global approach based on the free surface energy of a thermodynamic system containing the droplet and solid surface shows the static contact angle as a function of local surface chemistry and local wetting state at the contact line. A local approach, in which only local forces acting on the contact line are considered, results in the same equation. The fact that the local approach agrees with the global approach further demonstrates the static contact angle as a local wetting parameter. Additionally, the study also suggests that the wetting described by the Wenzel and Cassie equations is also the local wetting of the contact line rather than the global wetting of the droplet.

[Sport injuries in full contact and semi-contact karate].

Science.gov (United States)

Greier, K; Riechelmann, H; Ziemska, J

2014-03-01

Karate enjoys great popularity both in professional and recreational sports and can be classified into full, half and low contact styles. The aim of this study was the analysis of sports injuries in Kyokushinkai (full contact) and traditional Karate (semi-contact). In a retrospective study design, 215 active amateur karateka (114 full contact, 101 semi-contact) were interviewed by means of a standardised questionnaire regarding typical sport injuries during the last 36 months. Injuries were categorised into severity grade I (not requiring medical treatment), grade II (single medical treatment), grade III (several outpatient medical treatments) and grade IV (requiring hospitalisation). In total, 217 injuries were reported in detail. 125 injuries (58%) occurred in full contact and 92 (42%) in semi-contact karate. The time related injury rate of full contact karateka was 1.9/1000 h compared to 1.3/1000 h of semi-contact karateka (p injuries were musculoskeletal contusions (33% full contact, 20% semi-contact), followed by articular sprains with 19% and 16%. The lower extremity was affected twice as often in full contact (40%) as in semi-contact (20%) karate. Training injuries were reported by 80% of the full contact and 77% of the semi-contact karateka. Most injuries, both in training and competition, occurred in kumite. 75% of the reported injuries of full contact and 70% of semi-contact karateka were classified as low grade (I or II). The high rate of injuries during training and kumite (sparring) points to specific prevention goals. The emphasis should be put on proprioceptive training and consistent warm-up. In the actual competition the referees play a vital role regarding prevention. © Georg Thieme Verlag KG Stuttgart · New York.

Social Exclusion Based on Group Membership is a Form of Prejudice.

Science.gov (United States)

Cooley, Shelby; Elenbaas, Laura; Killen, Melanie

Children around the world are affected by bias, prejudice, and discrimination. In this chapter, we argue that intergroup social exclusion-exclusion of peers on the basis of group membership-is a form of prejudice. As such, research efforts should be directed at uncovering the negative intergroup attitudes that sustain these behaviors, and encouraging the development of children's capacity to resist biases in favor of inclusion and just treatment of others. In order to interpret what is known about intergroup social exclusion in childhood, as well as identify compelling issues for current investigation, we introduce our integrative social reasoning developmental model, which emphasizes how children weigh moral and social concerns in everyday peer contexts. This chapter emphasizes three areas of research that have contributed to understanding social inclusion and exclusion decisions in childhood which include the roles of: (1) intergroup contact and friendship, (2) peer group norms, and (3) messages from parents and teachers. While providing a background on the state of research to date, this chapter also pinpoints recent work, shedding new light on the complex interplay of moral reasoning and intergroup attitudes in children's inclusion and exclusion decisions. © 2016 Elsevier Inc. All rights reserved.

Practice patterns of radiotherapy in cervical cancer among member groups of the Gynecologic Cancer Intergroup (GCIG)

DEFF Research Database (Denmark)

Gaffney, David K; Du Bois, Andreas; Narayan, Kailash

2007-01-01

PURPOSE: The aim of this study was to describe radiotherapeutic practice of the treatment of cervical cancer in member groups of the Gynecologic Cancer Intergroup (GCIG). METHODS AND MATERIALS: A survey was developed and distributed to the members of the GCIG focusing on details of radiotherapy...... practice. Different scenarios were queried including advanced cervical cancer, postoperative patients, and para-aortic-positive lymph node cases. Items focused on indications for radiation therapy, radiation fields, dose, use of chemotherapy, brachytherapy and others. The cooperative groups from North...... America were compared with the other groups to evaluate potential differences in radiotherapy doses. RESULTS: A total of 39 surveys were returned from 13 different cooperative groups. For the treatment of advanced cervical cancer, external beam pelvic doses and total doses to point A were 47 + 3.5 Gy...

An analytical method for computing atomic contact areas in biomolecules.

Science.gov (United States)

Mach, Paul; Koehl, Patrice

2013-01-15

We propose a new analytical method for detecting and computing contacts between atoms in biomolecules. It is based on the alpha shape theory and proceeds in three steps. First, we compute the weighted Delaunay triangulation of the union of spheres representing the molecule. In the second step, the Delaunay complex is filtered to derive the dual complex. Finally, contacts between spheres are collected. In this approach, two atoms i and j are defined to be in contact if their centers are connected by an edge in the dual complex. The contact areas between atom i and its neighbors are computed based on the caps formed by these neighbors on the surface of i; the total area of all these caps is partitioned according to their spherical Laguerre Voronoi diagram on the surface of i. This method is analytical and its implementation in a new program BallContact is fast and robust. We have used BallContact to study contacts in a database of 1551 high resolution protein structures. We show that with this new definition of atomic contacts, we generate realistic representations of the environments of atoms and residues within a protein. In particular, we establish the importance of nonpolar contact areas that complement the information represented by the accessible surface areas. This new method bears similarity to the tessellation methods used to quantify atomic volumes and contacts, with the advantage that it does not require the presence of explicit solvent molecules if the surface of the protein is to be considered. © 2012 Wiley Periodicals, Inc. Copyright © 2012 Wiley Periodicals, Inc.

Convergence and divergence in leisure style among Whites and African Americans: toward an interracial contact hypothesis

Science.gov (United States)

Floyd F. Myron; Kimberly J. Shinew

1999-01-01

Drawing upon structural theory and social group perspectives, this study examined two propositions developed to explain the relationship between interracial contact and leisure preferences among African Americans and Whites. The first proposition stated that as interracial contact increases, the greater the probability of observing similarity in the leisure...

Defending or Challenging the Status Quo: Position Effects on Biased Intergroup Perceptions

Directory of Open Access Journals (Sweden)

Emma A. Bäck

2014-05-01

Full Text Available The default ideological position is status quo maintaining, and challenging the status quo is associated with increased efforts and risks. Nonetheless, some people choose to challenge the status quo. Therefore, to challenge the status quo should imply a strong belief in one’s position as the correct one, and thus efforts may be undertaken to undermine the position of others. Study 1 (N = 311 showed that challengers undermined, by ascribing more externality and less rationality, the position of defenders to a larger extent than defenders did of challengers’ position. Studies 2 (N = 135 and 3 (N = 109 tested if these effects were driven by the implied minority status of the challenging position. Results revealed no effects of experimentally manipulated numerical status, but challengers were again more biased than defenders. Study 3 also revealed that challengers felt more negatively toward their opponents (possibly due to greater social identification with like-minded others, and these negative emotions in turn predicted biased attributions. Results are important as they add to the understanding of how intergroup conflict may arise, providing explanations for why challengers are less tolerant of others’ point of view.

Transversity results and computations in symplectic field theory

Energy Technology Data Exchange (ETDEWEB)

Fabert, Oliver

2008-02-21

Although the definition of symplectic field theory suggests that one has to count holomorphic curves in cylindrical manifolds R x V equipped with a cylindrical almost complex structure J, it is already well-known from Gromov-Witten theory that, due to the presence of multiply-covered curves, we in general cannot achieve transversality for all moduli spaces even for generic choices of J. In this thesis we treat the transversality problem of symplectic field theory in two important cases. In the first part of this thesis we are concerned with the rational symplectic field theory of Hamiltonian mapping tori, which is also called the Floer case. For this observe that in the general geometric setup for symplectic field theory, the contact manifolds can be replaced by mapping tori M{sub {phi}} of symplectic manifolds (M,{omega}{sub M}) with symplectomorphisms {phi}. While the cylindrical contact homology of M{sub {phi}} is given by the Floer homologies of powers of {phi}, the other algebraic invariants of symplectic field theory for M{sub {phi}} provide natural generalizations of symplectic Floer homology. For symplectically aspherical M and Hamiltonian {phi} we study the moduli spaces of rational curves and prove a transversality result, which does not need the polyfold theory by Hofer, Wysocki and Zehnder and allows us to compute the full contact homology of M{sub {phi}} {approx_equal} S{sup 1} x M. The second part of this thesis is devoted to the branched covers of trivial cylinders over closed Reeb orbits, which are the trivial examples of punctured holomorphic curves studied in rational symplectic field theory. Since all moduli spaces of trivial curves with virtual dimension one cannot be regular, we use obstruction bundles in order to find compact perturbations making the Cauchy-Riemann operator transversal to the zero section and show that the algebraic count of elements in the resulting regular moduli spaces is zero. Once the analytical foundations of symplectic

Contact and Non-contact Measurements of Grinding Pins

Directory of Open Access Journals (Sweden)

Magdziak Marek

2015-01-01

Full Text Available The paper presents the results of contact and non-contact measurements of external profiles of selected grinding pins. The measurements were conducted in order to choose the appropriate measuring technique in the case of the considered measurement task. In the case of contact measurements the coordinate measuring machine ACCURA II was applied. The used coordinate measuring machine was equipped with the contact scanning probe VAST XT and the Calypso inspection software. Contact coordinate measurements were performed by using of different measurement strategies. The applied strategies included different scanning velocities and distances between measured points. Non-contact measurements were conducted by means of the tool presetter produced by the Mahr company. On the basis of gained results the guidelines concerning measurements of grinding pins were formulated. The measurements of analyzed grinding pins performed by means of the non-contact measuring system are characterized by higher reproducibility than the contact measurements. The low reproducibility of contact measurements may be connected with the inaccuracy of the selected coordinate measuring machine and the measuring probe, the measurement parameters and environmental conditions in the laboratory where the coordinate measuring machine is located. Moreover, the paper presents the possible application of results of conducted investigations. The results of non-contact measurements can be used in the simulation studies of grinding processes. The simulations may reduce the costs of machining processes.

Contact Geometry of Mesoscopic Thermodynamics and Dynamics

Directory of Open Access Journals (Sweden)

Miroslav Grmela

2014-03-01

Full Text Available The time evolution during which macroscopic systems reach thermodynamic equilibrium states proceeds as a continuous sequence of contact structure preserving transformations maximizing the entropy. This viewpoint of mesoscopic thermodynamics and dynamics provides a unified setting for the classical equilibrium and nonequilibrium thermodynamics, kinetic theory, and statistical mechanics. One of the illustrations presented in the paper is a new version of extended nonequilibrium thermodynamics with fluxes as extra state variables.

Finite element analysis of the contact between fuel rod and spacer grid

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyung Kyu; Kim, Young Koon; Kang, Heung Seok; Yoon, Kyung Ho; Song, Kee Nam [Korea Atomic Energy Research Institute, Taejon (Korea)

1999-01-01

For the research on the fretting failure problem of nuclear fuel, the contact length and normal stress field are evaluated for the contact between fuel rod and spacer grid by using the Finite Element Method (FEM). An assumption of semi-infiniteness is necessary for applying the Contact Mechanics which is based on the classical theory of elasticity to the present problem. For the contact problem of fuel fretting, the contact mechanical solutions could be utilized well with sufficient accuracy if the contact bodies (i.e., the cladding tube and the spacer grid) can be assumed as semi-infinite bodies. To this end, the contact length evaluated by FEM is discussed together with the relevant research which concerned the effect of dimension for the validity of the assumption of semi-infiniteness. Normal stress profile on the contact is also studied through comparing the theoretical and the FE results. For the analysis of contact problem by FEM, ANSYS code (Version 5.3) is utilized and the geometry is chosen to be the Hertzian (cylinder-to-cylinder), the strip-to-cylinder and the fuel rod/spacer grid contact (strip-to-tube). Present research will be utilized for accessing the fuel fretting problem by FEM together with the theoretical (i.e., contact mechanical) analysis which has been published as KAERI/TR-1113/98. (author). 15 refs., 44 figs., 4 tabs.

Contact area of rough spheres: Large scale simulations and simple scaling laws

Energy Technology Data Exchange (ETDEWEB)

Pastewka, Lars, E-mail: lars.pastewka@kit.edu [Institute for Applied Materials & MicroTribology Center muTC, Karlsruhe Institute of Technology, Engelbert-Arnold-Straße 4, 76131 Karlsruhe (Germany); Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218 (United States); Robbins, Mark O., E-mail: mr@pha.jhu.edu [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218 (United States)

2016-05-30

We use molecular simulations to study the nonadhesive and adhesive atomic-scale contact of rough spheres with radii ranging from nanometers to micrometers over more than ten orders of magnitude in applied normal load. At the lowest loads, the interfacial mechanics is governed by the contact mechanics of the first asperity that touches. The dependence of contact area on normal force becomes linear at intermediate loads and crosses over to Hertzian at the largest loads. By combining theories for the limiting cases of nominally flat rough surfaces and smooth spheres, we provide parameter-free analytical expressions for contact area over the whole range of loads. Our results establish a range of validity for common approximations that neglect curvature or roughness in modeling objects on scales from atomic force microscope tips to ball bearings.

Contact area of rough spheres: Large scale simulations and simple scaling laws

Science.gov (United States)

Pastewka, Lars; Robbins, Mark O.

2016-05-01

We use molecular simulations to study the nonadhesive and adhesive atomic-scale contact of rough spheres with radii ranging from nanometers to micrometers over more than ten orders of magnitude in applied normal load. At the lowest loads, the interfacial mechanics is governed by the contact mechanics of the first asperity that touches. The dependence of contact area on normal force becomes linear at intermediate loads and crosses over to Hertzian at the largest loads. By combining theories for the limiting cases of nominally flat rough surfaces and smooth spheres, we provide parameter-free analytical expressions for contact area over the whole range of loads. Our results establish a range of validity for common approximations that neglect curvature or roughness in modeling objects on scales from atomic force microscope tips to ball bearings.

The political solidarity model of social change: dynamics of self-categorization in intergroup power relations.

Science.gov (United States)

Subasic, Emina; Reynolds, Katherine J; Turner, John C

2008-11-01

Social and political change involves a challenge to the status quo in intergroup power relations. Traditionally, the social psychology of social change has focused on disadvantaged minority groups collectively challenging the decisions, actions, and policies of those in positions of established authority. In contrast, this article presents a political solidarity model of social change that explores the process by which members of the majority challenge the authority in solidarity with the minority. It is argued that political solidarity as a social change process involves a contest between the authority and the minority over the meaning of a shared (higher order) identity with the majority. When identity ceases to be shared with the authority and becomes shared with the minority, majority challenge to authority in solidarity with the minority becomes possible. The model's contributions to existing social psychological approaches to social change are also discussed.

Effects of intergroup upward comparison, trait self-esteem, and identity shift on state self-esteem and affect in upward comparison with in-group members

OpenAIRE

Isobe, Chikae; Ura, Mitsuhiro

2006-01-01

The present study investigated factors that protect people low in trait self-esteem (Low-SEs), who may be less skilled at constructing information in self-enhancing manners, from threats after interpersonal upward comparison with in-group members. We hypothesized that even Low-SEs can maintain their state self-esteem under intergroup upward comparison. Furthermore, this study explored the possibility that individuals used identity-shift, a strategy to maintain their personal identity, even in...

Data analysis strategies for the characterization of normal: superconductor point contacts by barrier strength parameter

Science.gov (United States)

Smith, Charles W.; Reinertson, Randal C.; Dolan, P. J., Jr.

1993-05-01

The theoretical description by Blonder, Tinkham, and Klapwijk [Phys. Rev. B 25, 4515 (1982)] of the I-V curves of normal: superconductor point contacts encompasses a broad range of experimental behavior, from the tunnel junction case, on the one hand, to the clean metallic microconstriction limit on the other. The theory characterizes point contacts in terms of a single parameter, the barrier strength. The differential conductance of a point contact, at zero bias, as a function of temperature, offers a direct experimental method by which the barrier strength parameter can be evaluated. In view of the full range of phenomena incorporated by this theory, we suggest several different strategies for the evaluation of the barrier strength parameter from data in the low and intermediate barrier strength regimes and for measurements in the low temperature (near T=0 K) and high temperature (near T=Tc) limits.

Host Students' Perspectives of Intercultural Contact in an Irish University

Science.gov (United States)

Dunne, Ciaran

2009-01-01

Given the increasing numbers of international students in Ireland and the lack of attention afforded to host culture students in existing research on intercultural relations in higher education, a grounded theory study was conducted in an Irish university exploring host (Irish) students' perspectives on intercultural contact. The study focused on…

Muon contact hyperfine field in metals: A DFT calculation

Science.gov (United States)

Onuorah, Ifeanyi John; Bonfà, Pietro; De Renzi, Roberto

2018-05-01

In positive muon spin rotation and relaxation spectroscopy it is becoming customary to take advantage of density functional theory (DFT) based computational methods to aid the experimental data analysis. DFT-aided muon site determination is especially useful for measurements performed in magnetic materials, where large contact hyperfine interactions may arise. Here we present a systematic analysis of the accuracy of the ab initio estimation of muon's hyperfine contact field on elemental transition metals, performing state-of-the-art spin-polarized plane-wave DFT and using the projector-augmented pseudopotential approach, which allows one to include the core state effects due to the spin ordering. We further validate this method in not-so-simple, noncentrosymmetric metallic compounds, presently of topical interest for their spiral magnetic structure giving rise to skyrmion phases, such as MnSi and MnGe. The calculated hyperfine fields agree with experimental values in all cases, provided the spontaneous spin magnetization of the metal is well reproduced within the approach. To overcome the known limits of the conventional mean-field approximation of DFT on itinerant magnets, we adopt the so-called reduced Stoner theory [L. Ortenzi et al., Phys. Rev. B 86, 064437 (2012), 10.1103/PhysRevB.86.064437]. We establish the accuracy of the estimated muon contact field in metallic compounds with DFT and our results show improved agreement with experiments compared to those of earlier publications.

Contact angle of a nanodrop on a nanorough solid surface.

Science.gov (United States)

Berim, Gersh O; Ruckenstein, Eli

2015-02-21

The contact angle of a cylindrical nanodrop on a nanorough solid surface is calculated, for both hydrophobic and hydrophilic surfaces, using the density functional theory. The emphasis of the paper is on the dependence of the contact angle on roughness. The roughness is modeled by rectangular pillars of infinite length located on the smooth surface of a substrate, with fluid-pillar interactions different in strength from the fluid-substrate ones. It is shown that for hydrophobic substrates the trend of the contact angle to increase with increasing roughness, which was noted in all previous studies, is not universally valid, but depends on the fluid-pillar interactions, pillar height, interpillar distance, as well as on the size of the drop. For hydrophilic substrate, an unusual kink-like dependence of the contact angle on the nanodrop size is found which is caused by the change in the location of the leading edges of the nanodrop on the surface. It is also shown that the Wenzel and Cassie-Baxter equations can not explain all the peculiarities of the contact angle of a nanodrop on a nanorough surface.

Surface topography and contact mechanics of dry and wet human skin

Directory of Open Access Journals (Sweden)

Alexander E. Kovalev

2014-08-01

Full Text Available The surface topography of the human wrist skin is studied by using optical and atomic force microscopy (AFM methods. By using these techniques the surface roughness power spectrum is obtained. The Persson contact mechanics theory is used to calculate the contact area for different magnifications, for the dry and wet skin. The measured friction coefficient between a glass ball and dry and wet skin can be explained assuming that a frictional shear stress σf ≈ 13 MPa and σf ≈ 5 MPa, respectively, act in the area of real contact during sliding. These frictional shear stresses are typical for sliding on surfaces of elastic bodies. The big increase in friction, which has been observed for glass sliding on wet skin as the skin dries up, can be explained as result of the increase in the contact area arising from the attraction of capillary bridges. Finally, we demonstrated that the real contact area can be properly defined only when a combination of both AFM and optical methods is used for power spectrum calculation.

Opening wedge trapezial osteotomy as possible treatment for early trapeziometacarpal osteoarthritis: a biomechanical investigation of radial subluxation, contact area, and contact pressure.

Science.gov (United States)

Cheema, Tahseen; Salas, Christina; Morrell, Nathan; Lansing, Letitia; Reda Taha, Mahmoud M; Mercer, Deana

2012-04-01

Radial subluxation and cartilage thinning have been associated with initiation and accelerated development of osteoarthritis of the trapeziometacarpal joint. Few investigators have reported on the benefits of opening wedge trapezial osteotomy for altering the contact mechanics of the trapeziometacarpal joint as a possible deterrent to the initiation or progression of osteoarthritis. We used cadaveric specimens to determine whether opening wedge osteotomy of the trapezium was successful in reducing radial subluxation of the metacarpal base and to quantify the contact area and pressure on the trapezial surface during simulated lateral pinch. We used 8 fresh-frozen specimens in this study. The flexor pollicis longus, abductor pollicis longus, adductor pollicis, abductor pollicis brevis, and flexor pollicis brevis/opponens pollicis tendons were each loaded to simulate the thumb in lateral pinch position. We measured radial subluxation from anteroposterior radiographs before and after placement of a 15° wedge. We used real-time sensors to analyze contact pressure and contact area distribution on the trapezium. Center of force in the normal joint under lateral pinch loading was primarily located in the dorsal region of the trapezium. After wedge placement, contact pressure increased in the ulnar-dorsal region by 76%. Mean contact area increased in the ulnar-dorsal region from 0.05 to 0.07 cm(2), and in the ulnar-volar region from 0.003 to 0.024 cm(2). The average reduction in joint subluxation was 64%. The 15° opening wedge osteotomy of the trapezium reduced radial subluxation of the metacarpal on the trapezium and increased contact pressure and contact area away from the diseased compartments of the trapezial surface. Trapezial osteotomy addresses the 2 preeminent theories about the initiation and progression of osteoarthritis. By reducing radial subluxation and altering contact pressure and contact area, trapezial osteotomy may prove an alternative to first

Equilibrium contact angle or the most-stable contact angle?

Science.gov (United States)

Montes Ruiz-Cabello, F J; Rodríguez-Valverde, M A; Cabrerizo-Vílchez, M A

2014-04-01

It is well-established that the equilibrium contact angle in a thermodynamic framework is an "unattainable" contact angle. Instead, the most-stable contact angle obtained from mechanical stimuli of the system is indeed experimentally accessible. Monitoring the susceptibility of a sessile drop to a mechanical stimulus enables to identify the most stable drop configuration within the practical range of contact angle hysteresis. Two different stimuli may be used with sessile drops: mechanical vibration and tilting. The most stable drop against vibration should reveal the changeless contact angle but against the gravity force, it should reveal the highest resistance to slide down. After the corresponding mechanical stimulus, once the excited drop configuration is examined, the focus will be on the contact angle of the initial drop configuration. This methodology needs to map significantly the static drop configurations with different stable contact angles. The most-stable contact angle, together with the advancing and receding contact angles, completes the description of physically realizable configurations of a solid-liquid system. Since the most-stable contact angle is energetically significant, it may be used in the Wenzel, Cassie or Cassie-Baxter equations accordingly or for the surface energy evaluation. © 2013 Elsevier B.V. All rights reserved.

Extending the theory of realistic conflict to competition in institutional settings: intergroup status and outcome.

Science.gov (United States)

Echebarria-Echabe, Agustin; Guede, Emilia Fernández

2003-12-01

The authors analyzed the extent to which the Theory of Realistic Conflict can be extended to institutional settings in which groups are not actively involved in decisions but are passive targets of decisions taken by an institutional authority (the rector). A negative interdependence between the in-group (psychology) and a high- or low-status outgroup (engineering versus nursing) was established by an institutional authority (the rector). The competition (induced by the rector) was beneficial (an increase in the budget previously invested in the faculty) or detrimental (a decrease in the budget) for the in-group. The results confirmed that competition affects mutual attitudes, images, and behaviors of groups even if the groups are passive targets of decisions that the institutional authority makes. Moreover, competition--regardless of whether beneficial or detrimental--deteriorated images of and attitudes toward high-status out-groups. In contrast, competition improved images and opinions about low-status out-groups, but only in the loss condition.

Prejudice, Ethnic Identity, Contact and Ethnic Group Preferences Among Dutch Young Adolescents

NARCIS (Netherlands)

Masson, C.N.; M.J.A.M. Verkuyten (Maykel)

1993-01-01

textabstractSocial identity theory, the contact hypothesis, and prejudice research are three important perspectives for studying ingroup information and preferences in the context of ethnic groups. This paper studies the utility of the three perspectives in a particular interethnic group context

The role of the roughness spectral breadth in elastic contact of rough surfaces

Science.gov (United States)

Yastrebov, Vladislav A.; Anciaux, Guillaume; Molinari, Jean-François

2017-10-01

We study frictionless and non-adhesive contact between elastic half-spaces with self-affine surfaces. Using a recently suggested corrective technique, we ensure an unprecedented accuracy in computation of the true contact area evolution under increasing pressure. This accuracy enables us to draw conclusions on the role of the surface's spectrum breadth (Nayak parameter) in the contact area evolution. We show that for a given normalized pressure, the contact area decreases logarithmically with the Nayak parameter. By linking the Nayak parameter with the Hurst exponent (or fractal dimension), we show the effect of the latter on the true contact area. This effect, undetectable for surfaces with poor spectral content, is quite strong for surfaces with rich spectra. Numerical results are compared with analytical models and other available numerical results. A phenomenological equation for the contact area growth is suggested with coefficients depending on the Nayak parameter. Using this equation, the pressure-dependent friction coefficient is deduced based on the adhesive theory of friction. Some observations on Persson's model of rough contact, whose prediction does not depend on Nayak parameter, are reported. Overall, the paper provides a unifying picture of rough elastic contact and clarifies discrepancies between preceding results.

Ziet men een tegenstelling tussen jong en oud? Een studie naar de invloed van sociale identificatie, competitie en contact

NARCIS (Netherlands)

Pauw, Rodinde; Maas, Ineke

2015-01-01

In this study we ask to what extent the Dutch population perceives a conflict between the young and old and how we can explain this. We use Social Identification Theory, Realistic Conflict Theory, and Contact Theory to derive hypotheses. These are tested with newly collected data on a representative

Non-Markovian electron dynamics in nanostructures coupled to dissipative contacts

Science.gov (United States)

Novakovic, B.; Knezevic, I.

2013-02-01

In quasiballistic semiconductor nanostructures, carrier exchange between the active region and dissipative contacts is the mechanism that governs relaxation. In this paper, we present a theoretical treatment of transient quantum transport in quasiballistic semiconductor nanostructures, which is based on the open system theory and valid on timescales much longer than the characteristic relaxation time in the contacts. The approach relies on a model interaction between the current-limiting active region and the contacts, given in the scattering-state basis. We derive a non-Markovian master equation for the irreversible evolution of the active region's many-body statistical operator by coarse-graining the exact dynamical map over the contact relaxation time. In order to obtain the response quantities of a nanostructure under bias, such as the potential and the charge and current densities, the non-Markovian master equation must be solved numerically together with the Schr\\"{o}dinger, Poisson, and continuity equations. We discuss how to numerically solve this coupled system of equations and illustrate the approach on the example of a silicon nin diode.

(Close) distance makes the heart grow fonder:Improving implicit racial attitudes and interracial interactions through approach behaviors.

Science.gov (United States)

Kawakami, Kerry; Phills, Curtis E; Steele, Jennifer R; Dovidio, John F

2007-06-01

In 4 studies, the authors examined the effect of approaching Blacks on implicit racial attitudes and immediacy behaviors. In Studies 1-3, participants were trained to pull a joystick toward themselves or to push it away from themselves when presented with photographs of Blacks, Whites, or Asians before completing an Implicit Association Test to measure racial bias. In Study 4, the effect of this training procedure on nonverbal behavior in an interracial contact situation was investigated. Results from the studies demonstrated that approaching Blacks decreased participants' implicit racial prejudice and increased immediacy when interacting with a Black confederate. The implications of these findings for current theories on approach, avoidance, and intergroup relations are discussed. (c) 2007 APA, all rights reserved.

Changes of Personal Network Composition and Inter-Group Ties from 1987 to 2005 in Hungary

Directory of Open Access Journals (Sweden)

VARGA V., Attila

2014-04-01

Full Text Available The following paper presents the changes and stability of assortative mixing, and inter-group ties in Hungary from 1987 to 2005. The demographic categories under investigation are age, sex, and education. The analysis has a special focus on the rearrangement of the context of tie formation, and the inequality of receiving choices into personal networks along social categories. The most substantial change during the period, is the strong decrease in gender homophily, and some strengthening of intergenerationalties. Both of these findings are in line with the observation that personal networks are recruited more often among the members of the nuclear-family. This latter phenomenon is probably due to the shrinking network size. However, this set of finding is prone to the methodological criticism formulated in the US context, that these observations are in fact the result of the interviewer effect. Finally, the study found stable patterns of educational network prestige, and describes the changes of social capital attached to categories of gender and age.

Block Copolymer Adhesion Measured by Contact Mechanics Methods

Science.gov (United States)

Falsafi, A.; Bates, S.; Tirrell, M.; Pocius, A. V.

1997-03-01

Adhesion measurements for a series of polyolefin diblocks and triblocks are presented. These materials have poly(ethylene-propylene) or poly(ethyl-ethylene) rubbery block, and semicrystalline polyethylene block as physical crosslinker. The experiments consist of compression and decompression profiles of contact area between the samples as a function of normal load, analyzed by the JKR Theory. The samples are prepared either by formation of caps from the bulk material in melting and subsequent cooling, and/or coating them in thin films on surface modified elastic foundations of polydimethylsiloxane caps. The latter minimizes the viscoelastic losses which are dominant in the bulk of material. The effect of molecular architecture and microstructure on adhesion energy and dynamics of separation, obtained from decompression experiments, is discussed in view of their influence on molecular arrangements at the contacting surfaces.

The implicit power motive in intergroup dialogues about the history of slavery.

Science.gov (United States)

Ditlmann, Ruth K; Purdie-Vaughns, Valerie; Dovidio, John F; Naft, Michael J

2017-01-01

This research demonstrates that individual differences in the implicit power motive (i.e., the concern with impact, influence, and control) moderate how African Americans communicate with White Americans in challenging intergroup dialogues. In a study with African American participants we find that the higher their implicit power motive, the more they use an affiliation strategy to communicate with a White American partner in a conversation context that evokes the history of slavery (Study 1). In a study with White American participants we find that, in the same conversation context, they are more engaged (i.e., open, attentive, and motivated) if they receive an affiliation message rather than a no-affiliation message from an African American partner (Study 2). In interracial dyads we find that African American participants' implicit power motives moderate how much they intend to signal warmth to a White American discussion partner, how much they display immediacy behaviors and use affiliation imagery in the discussion, and with what level of engagement White American participants respond (Study 3). High but not low implicit power African Americans thus employ a communication strategy-expressing affiliation and warmth-that can be effective for engaging White Americans with uncomfortable, race-identity-relevant topics. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Reducing contact resistance in graphene devices through contact area patterning.

Science.gov (United States)

Smith, Joshua T; Franklin, Aaron D; Farmer, Damon B; Dimitrakopoulos, Christos D

2013-04-23

Performance of graphene electronics is limited by contact resistance associated with the metal-graphene (M-G) interface, where unique transport challenges arise as carriers are injected from a 3D metal into a 2D-graphene sheet. In this work, enhanced carrier injection is experimentally achieved in graphene devices by forming cuts in the graphene within the contact regions. These cuts are oriented normal to the channel and facilitate bonding between the contact metal and carbon atoms at the graphene cut edges, reproducibly maximizing "edge-contacted" injection. Despite the reduction in M-G contact area caused by these cuts, we find that a 32% reduction in contact resistance results in Cu-contacted, two-terminal devices, while a 22% reduction is achieved for top-gated graphene transistors with Pd contacts as compared to conventionally fabricated devices. The crucial role of contact annealing to facilitate this improvement is also elucidated. This simple approach provides a reliable and reproducible means of lowering contact resistance in graphene devices to bolster performance. Importantly, this enhancement requires no additional processing steps.

Dynamic contact angle cycling homogenizes heterogeneous surfaces.

Science.gov (United States)

Belibel, R; Barbaud, C; Mora, L

2016-12-01

In order to reduce restenosis, the necessity to develop the appropriate coating material of metallic stent is a challenge for biomedicine and scientific research over the past decade. Therefore, biodegradable copolymers of poly((R,S)-3,3 dimethylmalic acid) (PDMMLA) were prepared in order to develop a new coating exhibiting different custom groups in its side chain and being able to carry a drug. This material will be in direct contact with cells and blood. It consists of carboxylic acid and hexylic groups used for hydrophilic and hydrophobic character, respectively. The study of this material wettability and dynamic surface properties is of importance due to the influence of the chemistry and the potential motility of these chemical groups on cell adhesion and polymer kinetic hydrolysis. Cassie theory was used for the theoretical correction of contact angles of these chemical heterogeneous surfaces coatings. Dynamic Surface Analysis was used as practical homogenizer of chemical heterogeneous surfaces by cycling during many cycles in water. In this work, we confirmed that, unlike receding contact angle, advancing contact angle is influenced by the difference of only 10% of acidic groups (%A) in side-chain of polymers. It linearly decreases with increasing acidity percentage. Hysteresis (H) is also a sensitive parameter which is discussed in this paper. Finally, we conclude that cycling provides real information, thus avoiding theoretical Cassie correction. H(10)is the most sensible parameter to %A. Copyright © 2016 Elsevier B.V. All rights reserved.

Prioritized Contact Transport Stream

Science.gov (United States)

Hunt, Walter Lee, Jr. (Inventor)

2015-01-01

A detection process, contact recognition process, classification process, and identification process are applied to raw sensor data to produce an identified contact record set containing one or more identified contact records. A prioritization process is applied to the identified contact record set to assign a contact priority to each contact record in the identified contact record set. Data are removed from the contact records in the identified contact record set based on the contact priorities assigned to those contact records. A first contact stream is produced from the resulting contact records. The first contact stream is streamed in a contact transport stream. The contact transport stream may include and stream additional contact streams. The contact transport stream may be varied dynamically over time based on parameters such as available bandwidth, contact priority, presence/absence of contacts, system state, and configuration parameters.

Elements of friction theory and nanotribology from statistical physics to quantum information

CERN Document Server

Gnecco, Enrico

2015-01-01

Combining the classical theories of contact mechanics and lubrication with the study of friction on the nanometer range, this multi-scale book for researchers and students alike guides the reader deftly through the mechanisms governing friction processes, based on state-of-the-art models and experimental results. The first book in the field to incorporate recent research on nanotribology with classical theories of contact mechanics, this unique text explores atomic scale scratches, non-contact friction and fishing of molecular nanowires as observed in the lab. Beginning with simple key concepts, the reader is guided through progressively more complex topics, such as contact of self-affine surfaces and nanomanipulation, in a consistent style, encompassing both macroscopic and atomistic descriptions of friction, and using unified notations to enable use by physicists and engineers across the scientific community.

American Contact Dermatitis Society Contact Allergy Management Program: An Epidemiologic Tool to Determine Relative Prevalence of Contact Allergens.

Science.gov (United States)

Scheman, Andrew; Severson, David

2016-01-01

Data on the prevalence of contact allergy in North America are currently reported by groups of academic contact allergy specialists at select academic centers. Sampling of data from numerous centers across North America, including practices performing more limited patch testing, would provide a broader perspective of contact allergen prevalence in North America. The American Contact Dermatitis Society Contact Allergy Management Program is an ideal tool for collection of epidemiologic data regarding contact allergy prevalence in North America. The aim of the study was to identify the relative prevalence of contact allergy to common contact allergens in North America. Mapping of Contact Allergy Management Program (CAMP) data was performed to allow analysis of how frequently searches were performed for various contact allergens. The number of searches performed for specific allergens provides a measure of the relative prevalence of contact allergy to these allergens. The top 35 allergens for the period from November 18, 2012 to November 18, 2013 are reported. Although these data are useful, specific recommendations for minor alterations to CAMP are discussed, which will allow future CAMP data to be stratified and more powerful. With minor modifications, CAMP can provide a quantum leap in the reporting of contact allergy epidemiologic data in North America.

Non-linear frequency and amplitude modulation of a nano-contact spin torque oscillator

OpenAIRE

Muduli, P. K.; Pogoryelov, Ye.; Bonetti, S.; Consolo, G.; Mancoff, Fred; Åkerman, Johan

2009-01-01

We study the current controlled modulation of a nano-contact spin torque oscillator. Three principally different cases of frequency non-linearity ($d^{2}f/dI^{2}_{dc}$ being zero, positive, and negative) are investigated. Standard non-linear frequency modulation theory is able to accurately describe the frequency shifts during modulation. However, the power of the modulated sidebands only agrees with calculations based on a recent theory of combined non-linear frequency and amplitude modulation.

Language Contact.

Science.gov (United States)

Nelde, Peter Hans

1995-01-01

Examines the phenomenon of language contact and recent trends in linguistic contact research, which focuses on language use, language users, and language spheres. Also discusses the role of linguistic and cultural conflicts in language contact situations. (13 references) (MDM)

With a Little Help from Our Friends: The Impact of Cross-group Friendship on Acculturation Preferences

OpenAIRE

Zagefka, Hanna; Lay, Siugmin; Astudillo, Jorge; Lickel, Brian; Brown, Rupert; Tropp, Linda; Gonzalez, Roberto; Bernardino, Michelle; Hässler, Tabea

2018-01-01

Despite extensive research on intergroup contact and acculturation, our understanding of how contact affects receiving society members' preferences for acculturation orientation of immigrants over time is still relatively rudimentary. This longitudinal study examined how perceived group similarity and outgroup trust mediate the effects of cross-group friendship on acculturation preferences (culture maintenance and culture adoption) of the receiving society. It was predicted that cross-group f...

Anomalous Temperature Dependence in Metal-Black Phosphorus Contact.

Science.gov (United States)

Li, Xuefei; Grassi, Roberto; Li, Sichao; Li, Tiaoyang; Xiong, Xiong; Low, Tony; Wu, Yanqing

2018-01-10

Metal-semiconductor contact has been the performance limiting problem for electronic devices and also dictates the scaling potential for future generation devices based on novel channel materials. Two-dimensional semiconductors beyond graphene, particularly few layer black phosphorus, have attracted much attention due to their exceptional electronic properties such as anisotropy and high mobility. However, due to its ultrathin body nature, few layer black phosphorus-metal contact behaves differently than conventional Schottky barrier (SB) junctions, and the mechanisms of its carrier transport across such a barrier remain elusive. In this work, we examine the transport characteristic of metal-black phosphorus contact under varying temperature. We elucidated the origin of apparent negative SB heights extracted from classical thermionic emission model and also the phenomenon of metal-insulator transition observed in the current-temperature transistor characteristic. In essence, we found that the SB height can be modulated by the back-gate voltage, which beyond a certain critical point becomes so low that the injected carrier can no longer be described by the conventional thermionic emission theory. The transition from transport dominated by a Maxwell-Boltzmann distribution for the high energy tail states, to that of a Fermi distribution by low energy Fermi sea electrons, is the physical origin of the observed metal-insulator transition. We identified two distinctive tunneling limited transport regimes in the contact: vertical and longitudinal tunneling.

Dynamics of the Molten Contact Line

Science.gov (United States)

Sonin, Ain A.; Duthaler, Gregg; Liu, Michael; Torresola, Javier; Qiu, Taiqing

1999-01-01

The purpose of this program is to develop a basic understanding of how a molten material front spreads over a solid that is below its melting point, arrests, and freezes. Our hope is that the work will contribute toward a scientific knowledge base for certain new applications involving molten droplet deposition, including the "printing" of arbitrary three-dimensional objects by precise deposition of individual molten microdrops that solidify after impact. Little information is available at this time on the capillarity-driven motion and arrest of molten contact line regions. Schiaffino and Sonin investigated the arrest of the contact line of a molten microcrystalline wax spreading over a subcooled solid "target" of the same material. They found that contact line arrest takes place at an apparent liquid contact angle that depends primarily on the Stefan number S=c(T(sub f) -T(sub t)/L based on the temperature difference between the fusion point and the target temperature, and proposed that contact line arrest occurs when the liquid's dynamic contact angle approaches the angle of attack of the solidification front just behind the contact line. They also showed, however, that the conventional continuum equations and boundary conditions have no meaningful solution for this angle. The solidification front angle is determined by the heat flux just behind the contact line, and the heat flux is singular at that point. By comparing experiments with numerical computations, Schiaffino and Sonin estimated that the conventional solidification model must break down within a distance of order 0.1 - 1 microns of the contact line. The physical mechanism for this breakdown is as yet undetermined, and no first-principles theory exists for the contact angle at arrest. Schiaffino and Sonin also presented a framework for understanding how to moderate Weber number molten droplet deposition in terms of similarity laws and experimentation. The study is based on experiments with three molten

Evaluation of anti-tuberculosis antibodies in healthy contact and non-contacts persons

International Nuclear Information System (INIS)

Aziz, N; Bukhari, M.H; Muneer, M; Tayyab, M; Chaudhry, N.A.

2006-01-01

This study was conducted to see the presence of the antimycobacterial antibodies in healthy household contacts of tuberculosis patients and healthy normal subjects who have never been in contact with tuberculosis patients. A total of 200 subjects, 120 with history of household contact and 80 without such history were included in the study. Routine Haematological investigations were performed and all the sera of 200 subjects were tested who 19M, 19G and IgA anti tuberculosis antibodies using ELISA technique. There was no difference in the average age of the household contacts and non-contacts. The complaints of pyrexia, night sweats and loss of weight was more in house hold contacts as compared to non-contacts. The awareness about BCG vaccination was equal among the household contacts and non-contacts. The combined serological positivity of the household contacts was 65.8% and the combined serological positivity for non-contacts was 34.1%. There was no statistically significant difference in the presence of 19M among household contacts as compared to non-contacts. However both IgG and 19A were present in significantly higher number of household contacts as compared to non contacts. This study concludes that the persons living in the house with a patient suffering from active pulmonary tuberculosis (household contact) have more chances of being infected with Mycobacterium tuberculosis as compared to the healthy non-contacts. (author)

Energy flow in non-equilibrium conformal field theory

Science.gov (United States)

Bernard, Denis; Doyon, Benjamin

2012-09-01

We study the energy current and its fluctuations in quantum gapless 1d systems far from equilibrium modeled by conformal field theory, where two separated halves are prepared at distinct temperatures and glued together at a point contact. We prove that these systems converge towards steady states, and give a general description of such non-equilibrium steady states in terms of quantum field theory data. We compute the large deviation function, also called the full counting statistics, of energy transfer through the contact. These are universal and satisfy fluctuation relations. We provide a simple representation of these quantum fluctuations in terms of classical Poisson processes whose intensities are proportional to Boltzmann weights.

Right-wing authoritarianism and stereotype-driven expectations interact in shaping intergroup trust in one-shot vs multiple-round social interactions.

Science.gov (United States)

Ponsi, Giorgia; Panasiti, Maria Serena; Aglioti, Salvatore Maria; Liuzza, Marco Tullio

2017-01-01

Trust towards unrelated individuals is often conditioned by information about previous social interactions that can be derived from either personal or vicarious experience (e.g., reputation). Intergroup stereotypes can be operationalized as expectations about other groups' traits/attitudes/behaviors that heavily influence our behavioral predictions when interacting with them. In this study we investigated the role of perceived social dimensions of the Stereotype Content Model (SCM)-Warmth (W) and Competence (C)-in affecting trusting behavior towards different European national group members during the Trust Game. Given the well-known role of ideological attitudes in regulating stereotypes, we also measured individual differences in right-wing authoritarianism (RWA). In Experiment 1, we designed an online survey to study one-shot intergroup trust decisions by employing putative members of the European Union states which were also rated along SCM dimensions. We found that low-RWA participants' trusting behavior was driven by perceived warmth (i.e., the dimension signaling the benevolence of social intentions) when interacting with low-C groups. In Experiment 2, we investigated the dynamics of trust in a multiple-round version of the European Trust Game. We found that in low-RWA participants trusting behavior decreased over time when interacting with high-W groups (i.e., expected to reciprocate trust), but did not change when interacting with low-W groups (i.e., expected not to reciprocate trust). Moreover, we found that high-RWA participants' trusting behavior decreased when facing low-W groups but not high-W ones. This suggests that low-RWA individuals employ reputational priors but are also permeable to external evidence when learning about others' trustworthiness. In contrast, high-RWA individuals kept relying on stereotypes despite contextual information. These results confirm the pivotal role played by reputational priors triggered by perceived warmth in shaping

Right-wing authoritarianism and stereotype-driven expectations interact in shaping intergroup trust in one-shot vs multiple-round social interactions.

Directory of Open Access Journals (Sweden)

Giorgia Ponsi

Full Text Available Trust towards unrelated individuals is often conditioned by information about previous social interactions that can be derived from either personal or vicarious experience (e.g., reputation. Intergroup stereotypes can be operationalized as expectations about other groups' traits/attitudes/behaviors that heavily influence our behavioral predictions when interacting with them. In this study we investigated the role of perceived social dimensions of the Stereotype Content Model (SCM-Warmth (W and Competence (C-in affecting trusting behavior towards different European national group members during the Trust Game. Given the well-known role of ideological attitudes in regulating stereotypes, we also measured individual differences in right-wing authoritarianism (RWA. In Experiment 1, we designed an online survey to study one-shot intergroup trust decisions by employing putative members of the European Union states which were also rated along SCM dimensions. We found that low-RWA participants' trusting behavior was driven by perceived warmth (i.e., the dimension signaling the benevolence of social intentions when interacting with low-C groups. In Experiment 2, we investigated the dynamics of trust in a multiple-round version of the European Trust Game. We found that in low-RWA participants trusting behavior decreased over time when interacting with high-W groups (i.e., expected to reciprocate trust, but did not change when interacting with low-W groups (i.e., expected not to reciprocate trust. Moreover, we found that high-RWA participants' trusting behavior decreased when facing low-W groups but not high-W ones. This suggests that low-RWA individuals employ reputational priors but are also permeable to external evidence when learning about others' trustworthiness. In contrast, high-RWA individuals kept relying on stereotypes despite contextual information. These results confirm the pivotal role played by reputational priors triggered by perceived

Contact Lens Care

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... Consumers Consumer Information by Audience For Women Contact Lens Care Share Tweet Linkedin Pin it More sharing ... www.fda.gov/medwatch Learn More about Contact Lens Care Other Tips on Contact Lenses Decorative Contact ...

Interventions to reduce discrimination and stigma: the state of the art.

Science.gov (United States)

Gronholm, Petra C; Henderson, Claire; Deb, Tanya; Thornicroft, Graham

2017-03-01

There is a rich literature on the nature of mental health-related stigma and the processes by which it severely affects the life chances of people with mental health problems. However, applying this knowledge to deliver and evaluate interventions to reduce discrimination and stigma in a lasting way is a complex and long-term challenge. We conducted a narrative synthesis of systematic reviews published since 2012, and supplemented this with papers published subsequently as examples of more recent work. There is evidence for small to moderate positive impacts of both mass media campaigns and interventions for target groups in terms of stigma-related knowledge, attitudes, and intended behaviour in terms of desire for contact. However, the limited evidence from longer follow-up times suggests that it is not clear whether short-term contact interventions have a lasting impact. The risk that short-term interventions may only have a short-term impact suggests a need to study longer term interventions and to use interim process and outcome data to improve interventions along the way. There is scope for more thorough application of intergroup contact theory whenever contact is used and of evidence-based teaching and assessment methods when skills training is used for target groups.

Angels and demons are among us: assessing individual differences in belief in pure evil and belief in pure good.

Science.gov (United States)

Webster, Russell J; Saucier, Donald A

2013-11-01

We conducted five studies to demonstrate that individuals' beliefs in pure evil (BPE) and in pure good (BPG) are valid and important psychological constructs. First, these studies together demonstrated that BPE and BPG are reliable, unitary, and stable constructs each composed of eight theoretically interdependent dimensions. Second, these studies showed that across a wide variety of different measures, higher BPE consistently related to greater intergroup aggression (e.g., supporting the death penalty and preemptive military aggression) and less intergroup prosociality (e.g., opposing criminal rehabilitation, proracial policies, and beneficial social programs), while higher BPG consistently related to less intergroup aggression (e.g., opposing proviolent foreign relations and torture) and greater intergroup prosociality (e.g., supporting criminal rehabilitation and support for diplomacy). In sum, these studies evidence that BPE and BPG relate to aggressive and prosocial orientations toward others and have strong potential to advance current theories on prejudice, aggression, and prosociality.

Computerized Modeling and Loaded Tooth Contact Analysis of Hypoid Gears Manufactured by Face Hobbing Process

Science.gov (United States)

Nishino, Takayuki

The face hobbing process has been widely applied in automotive industry. But so far few analytical tools have been developed. This makes it difficult for us to optimize gear design. To settle this situation, this study aims at developing a computerized tool to predict the running performances such as loaded tooth contact pattern, static transmission error and so on. First, based upon kinematical analysis of a cutting machine, a mathematical description of tooth surface generation is given. Second, based upon the theory of gearing and differential geometry, conjugate tooth surfaces are studied. Then contact lines are generated. Third, load distribution along contact lines is formulated. Last, the numerical model is validated by measuring loaded transmission error and loaded tooth contact pattern.

Superconducting Sweet-Spot in Microcrystalline Graphite Revealed by Point-Contact Spectroscopy

Science.gov (United States)

Arnold, F.; Nyéki, J.; Saunders, J.

2018-05-01

In this letter we describe the observation of a magnetic field dependent electronic gap, suggestive of local superconductivity, in the point-contact spectrum of micro-crystalline graphite. Magnetic field dependent point-contact spectroscopy was carried out at a temperature of 1.8K using an etched aluminium tip. At zero field a gap structure in the differential conductance is observed, showing a gap of Δ = 4.2 meV. On applying magnetic fields of up to 500mT, this gap gradually closes, following the theoretical prediction by Ginzburg and Landau for a fully flux-penetrated superconductor. By applying BCS-theory, we infer a critical superconducting temperature of 14K.

Perceived Peer and Parent Out-Group Norms, Cultural Identity, and Adolescents' Reasoning About Peer Intergroup Exclusion.

Science.gov (United States)

Brenick, Alaina; Romano, Kelly

2016-09-01

Cultural group identity and group norms are significantly related to social exclusion evaluations (Bennett, ). This study examined 241 Jewish-American mid (M = 14.18 years, SD = 0.42) to late (M = 17.21 years, SD = 0.43; MageTOTAL  = 15.54 years, SD = 1.57) adolescents' cultural identities and contextually salient perceived group norms in relation to their evaluations of Arab-American inclusion and exclusion across two contexts (peers vs. family at home). Results suggest that perceived group norms are related to the context in which they are applied: parents in the home and peers in the peer context. Peers remained a significant source of perceived group norms in the home context. Significant interactions emerged between perceived parent group norms and cultural identity. Findings highlight the need to address group-specific norms by context to ensure maximum effectiveness for intergroup interventions. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

A human capital predictive model for agent performance in contact centres

Directory of Open Access Journals (Sweden)

Chris Jacobs

2011-10-01

Research purpose: The primary focus of this article was to develop a theoretically derived human capital predictive model for agent performance in contact centres and Business Process Outsourcing (BPO based on a review of current empirical research literature. Motivation for the study: The study was motivated by the need for a human capital predictive model that can predict agent and overall business performance. Research design: A nonempirical (theoretical research paradigm was adopted for this study and more specifically a theory or model-building approach was followed. A systematic review of published empirical research articles (for the period 2000–2009 in scholarly search portals was performed. Main findings: Eight building blocks of the human capital predictive model for agent performance in contact centres were identified. Forty-two of the human capital contact centre related articles are detailed in this study. Key empirical findings suggest that person– environment fit, job demands-resources, human resources management practices, engagement, agent well-being, agent competence; turnover intention; and agent performance are related to contact centre performance. Practical/managerial implications: The human capital predictive model serves as an operational management model that has performance implications for agents and ultimately influences the contact centre’s overall business performance. Contribution/value-add: This research can contribute to the fields of human resource management (HRM, human capital and performance management within the contact centre and BPO environment.

Apparent contact angle and contact angle hysteresis on liquid infused surfaces.

Science.gov (United States)

Semprebon, Ciro; McHale, Glen; Kusumaatmaja, Halim

2016-12-21

We theoretically investigate the apparent contact angle and contact angle hysteresis of a droplet placed on a liquid infused surface. We show that the apparent contact angle is not uniquely defined by material parameters, but also has a dependence on the relative size between the droplet and its surrounding wetting ridge formed by the infusing liquid. We derive a closed form expression for the contact angle in the limit of vanishing wetting ridge, and compute the correction for small but finite ridge, which corresponds to an effective line tension term. We also predict contact angle hysteresis on liquid infused surfaces generated by the pinning of the contact lines by the surface corrugations. Our analytical expressions for both the apparent contact angle and contact angle hysteresis can be interpreted as 'weighted sums' between the contact angles of the infusing liquid relative to the droplet and surrounding gas phases, where the weighting coefficients are given by ratios of the fluid surface tensions.

Evaluation of metal–nanowire electrical contacts by measuring contact end resistance

International Nuclear Information System (INIS)

Park, Hongsik; Beresford, Roderic; Xu, Jimmy; Ha, Ryong; Choi, Heon-Jin; Shin, Hyunjung

2012-01-01

It is known, but often unappreciated, that the performance of nanowire (NW)-based electrical devices can be significantly affected by electrical contacts between electrodes and NWs, sometimes to the extent that it is really the contacts that determine the performance. To correctly understand and design NW device operation, it is thus important to carefully measure the contact resistance and evaluate the contact parameters, specific contact resistance and transfer length. A four-terminal pattern or a transmission line model (TLM) pattern has been widely used to measure contact resistance of NW devices and the TLM has been typically used to extract contact parameters of NW devices. However, the conventional method assumes that the electrical properties of semiconducting NW regions covered by a metal are not changed after electrode formation. In this study, we report that the conventional methods for contact evaluation can give rise to considerable errors because of an altered property of the NW under the electrodes. We demonstrate that more correct contact resistance can be measured from the TLM pattern rather than the four-terminal pattern and correct contact parameters including the effects of changed NW properties under electrodes can be evaluated by using the contact end resistance measurement method. (paper)

Strangeness S = -2 baryon-baryon interactions using chiral effective field theory

NARCIS (Netherlands)

Polinder, H.; Haidenbauer, J.; Meissner, U.G.

2007-01-01

We derive the leading order strangeness S =−2 baryon–baryon interactions in chiral effective field theory. The potential consists of contact terms without derivatives and of one-pseudoscalar-meson exchanges. The contact terms and the couplings of the pseudoscalar mesons to the baryons are related

US Intergroup Anal Carcinoma Trial: Tumor Diameter Predicts for Colostomy

Science.gov (United States)

Ajani, Jaffer A.; Winter, Kathryn A.; Gunderson, Leonard L.; Pedersen, John; Benson, Al B.; Thomas, Charles R.; Mayer, Robert J.; Haddock, Michael G.; Rich, Tyvin A.; Willett, Christopher G.

2009-01-01

Purpose The US Gastrointestinal Intergroup Radiation Therapy Oncology Group 98-11 anal carcinoma trial showed that cisplatin-based concurrent chemoradiotherapy resulted in a significantly higher rate of colostomy compared with mitomycin-based therapy. Established prognostic variables for patients with anal carcinoma include tumor diameter, clinical nodal status, and sex, but pretreatment variables that would predict the likelihood of colostomy are unknown. Methods A secondary analysis was performed by combining patients in the two treatment arms to evaluate whether new predictive and prognostic variables would emerge. Univariate and multivariate analyses were carried out to correlate overall survival (OS), disease-free survival, and time to colostomy (TTC) with pretreatment and treatment variables. Results Of 682 patients enrolled, 644 patients were assessable and analyzed. In the multivariate analysis, tumor-related prognosticators for poorer OS included node-positive cancer (P ≤ .0001), large (> 5 cm) tumor diameter (P = .01), and male sex (P = .016). In the treatment-related categories, cisplatin-based therapy was statistically significantly associated with a higher rate of colostomy (P = .03) than was mitomycin-based therapy. In the pretreatment variables category, only large tumor diameter independently predicted for TTC (P = .008). Similarly, the cumulative 5-year colostomy rate was statistically significantly higher for large tumor diameter than for small tumor diameter (Gray's test; P = .0074). Clinical nodal status and sex were not predictive of TTC. Conclusion The combined analysis of the two arms of RTOG 98-11, representing the largest prospective database, reveals that tumor diameter (irrespective of the nodal status) is the only independent pretreatment variable that predicts TTC and 5-year colostomy rate in patients with anal carcinoma. PMID:19139424

Theories of Matter, Space and Time, Volume 2; Quantum theories

Science.gov (United States)

Evans, N.; King, S. F.

2018-06-01

This book and its prequel Theories of Matter Space and Time: Classical Theories grew out of courses that we have both taught as part of the undergraduate degree program in Physics at Southampton University, UK. Our goal was to guide the full MPhys undergraduate cohort through some of the trickier areas of theoretical physics that we expect our undergraduates to master. Here we teach the student to understand first quantized relativistic quantum theories. We first quickly review the basics of quantum mechanics which should be familiar to the reader from a prior course. Then we will link the Schrödinger equation to the principle of least action introducing Feynman's path integral methods. Next, we present the relativistic wave equations of Klein, Gordon and Dirac. Finally, we convert Maxwell's equations of electromagnetism to a wave equation for photons and make contact with quantum electrodynamics (QED) at a first quantized level. Between the two volumes we hope to move a student's understanding from their prior courses to a place where they are ready, beyond, to embark on graduate level courses on quantum field theory.

The effect of adhesion on the contact radius in atomic force microscopy indentation

International Nuclear Information System (INIS)

Sirghi, L; Rossi, F

2009-01-01

The effect of adhesion on nanoscale indentation experiments makes the interpretation of force-displacement curves acquired in these experiments very difficult. The indentation force results from the addition of adhesive and elastic forces at the indenter-sample contact. The evolution of the two forces during the indentation is determined by the variation of the indenter-sample contact radius. In the present work the variation of contact radius during atomic force microscopy (AFM) indentation of elastic and adhesive samples with conical indenters (AFM tips) is indirectly determined by measurements of the contact dynamic stiffness. For weak sample deformations, the contact radius is determined mainly by the adhesion force and indenter apex radius. For strong sample deformations, the contact radius increases linearly with the increase of the indenter displacement, the slope of this linear dependence being in agreement with Sneddon's theory of indentation (Sneddon 1965 Int. J. Eng. Sci. 3 47). Based on these results, a theoretical expression of indentation force dependence on displacement is found. This expression allows for determination of the thermodynamic work of adhesion at the indenter-sample interface and the sample elasticity modulus.

Granular dynamics, contact mechanics and particle system simulations a DEM study

CERN Document Server

Thornton, Colin

2015-01-01

This book is devoted to the Discrete Element Method (DEM) technique, a discontinuum modelling approach that takes into account the fact that granular materials are composed of discrete particles which interact with each other at the microscale level. This numerical simulation technique can be used both for dispersed systems in which the particle-particle interactions are collisional and compact systems of particles with multiple enduring contacts. The book provides an extensive and detailed explanation of the theoretical background of DEM. Contact mechanics theories for elastic, elastic-plastic, adhesive elastic and adhesive elastic-plastic particle-particle interactions are presented. Other contact force models are also discussed, including corrections to some of these models as described in the literature, and important areas of further research are identified. A key issue in DEM simulations is whether or not a code can reliably simulate the simplest of systems, namely the single particle oblique impact wit...

Nonlinear Displacement Discontinuity Model for Generalized Rayleigh Wave in Contact Interface

Energy Technology Data Exchange (ETDEWEB)

Kim, No Hyu; Yang, Seung Yong [Korea University of Technology and Education, Cheonan (Korea, Republic of)

2007-12-15

Imperfectly jointed interface serves as mechanical waveguide for elastic waves and gives rise to two distinct kinds of guided wave propagating along the interface. Contact acoustic nonlinearity (CAN) is known to plays major role in the generation of these interface waves called generalized Rayleigh waves in non-welded interface. Closed crack is modeled as non-welded interface that has nonlinear discontinuity condition in displacement across its boundary. Mathematical analysis of boundary conditions and wave equation is conducted to investigate the dispersive characteristics of the interface waves. Existence of the generalized Rayleigh wave(interface wave) in nonlinear contact interface is verified in theory where the dispersion equation for the interface wave is formulated and analyzed. It reveals that the interface waves have two distinct modes and that the phase velocity of anti-symmetric wave mode is highly dependent on contact conditions represented by linear and nonlinear dimensionless specific stiffness

Nonlinear Displacement Discontinuity Model for Generalized Rayleigh Wave in Contact Interface

International Nuclear Information System (INIS)

Kim, No Hyu; Yang, Seung Yong

2007-01-01

Imperfectly jointed interface serves as mechanical waveguide for elastic waves and gives rise to two distinct kinds of guided wave propagating along the interface. Contact acoustic nonlinearity (CAN) is known to plays major role in the generation of these interface waves called generalized Rayleigh waves in non-welded interface. Closed crack is modeled as non-welded interface that has nonlinear discontinuity condition in displacement across its boundary. Mathematical analysis of boundary conditions and wave equation is conducted to investigate the dispersive characteristics of the interface waves. Existence of the generalized Rayleigh wave(interface wave) in nonlinear contact interface is verified in theory where the dispersion equation for the interface wave is formulated and analyzed. It reveals that the interface waves have two distinct modes and that the phase velocity of anti-symmetric wave mode is highly dependent on contact conditions represented by linear and nonlinear dimensionless specific stiffness

Measuring contact area in a sliding human finger-pad contact.

Science.gov (United States)

Liu, X; Carré, M J; Zhang, Q; Lu, Z; Matcher, S J; Lewis, R

2018-02-01

The work outlined in this paper was aimed at achieving further understanding of skin frictional behaviour by investigating the contact area between human finger-pads and flat surfaces. Both the static and the dynamic contact areas (in macro- and micro-scales) were measured using various techniques, including ink printing, optical coherence tomography (OCT) and Digital Image Correlation (DIC). In the studies of the static measurements using ink printing, the experimental results showed that the apparent and the real contact area increased with load following a piecewise linear correlation function for a finger-pad in contact with paper sheets. Comparisons indicated that the OCT method is a reliable and effective method to investigate the real contact area of a finger-pad and allow micro-scale analysis. The apparent contact area (from the DIC measurements) was found to reduce with time in the transition from the static phase to the dynamic phase while the real area of contact (from OCT) increased. The results from this study enable the interaction between finger-pads and contact object surface to be better analysed, and hence improve the understanding of skin friction. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Electric contact arcing

International Nuclear Information System (INIS)

Cuthrell, R.E.

1976-01-01

Electrical contacts must function properly in many types of components used in nuclear weapon systems. Design, application, and testing of these components require detailed knowledge of chemical and physical phenomena associated with stockpile storage, stockpile testing, and operation. In the past, investigation of these phenomena has led to significant discoveries on the effects of surface contaminants, friction and wear, and the mechanics of closure on contact performance. A recent investigation of contact arcing phenomena which revealed that, preceding contact closure, arcs may occur at voltages lower than had been previously known is described. This discovery is important, since arcing may damage contacts, and repetitive testing of contacts performed as part of a quality assurance program might produce cumulative damage that would yield misleading life-test data and could prevent proper operation of the contacts at some time in the future. This damage can be avoided by determining the conditions under which arcing occurs, and ensuring that these conditions are avoided in contact testing

Multimarket contact and performance: Evidence from emerging economies

Directory of Open Access Journals (Sweden)

Beatriz Domínguez

2016-10-01

Full Text Available The organizational structure of multinational enterprises (MNEs is mainly made up of subsidiaries located in emerging and advanced countries. Consequently, they usually compete against the same rivals simultaneously in both emerging and advanced contexts. Multimarket contact (MMC theory analyzes the competitive dynamics that arise in these situations. However, researchers have paid more attention to the consequences of multimarket contact in developed countries than to its effect in emerging countries. To explore the impact of the macroenvironment on the relationship between MMC and performance, we examine how coinciding with multimarket rivals in emerging economies alters the effect of MMC on firm performance. Our research, which is developed with a sample from the mobile telecommunications industry, shows that the presence of MNEs in emerging countries hinders the development of mutual forbearance practices and, therefore, reduces the positive effect of MMC on firm performance.

Contact mechanics and friction physical principles and applications

CERN Document Server

Popov, Valentin L

2017-01-01

This application-oriented book introduces readers to the associations and relationships between contact mechanics and friction, providing them with a deeper understanding of tribology. It addresses the related phenomena of contacts, adhesion, capillary forces, friction, lubrication, and wear from a consistent point of view. The author presents (1) methods for rough estimates of tribological quantities, (2) simple and general methods for analytical calculations, and (3) the crossover into numerical simulation methods, the goal being to convey a consistent view of tribological processes at various scales of magnitude (from nanotribology to earthquake research). The book also explores the system dynamic aspects of tribological systems, such as squeal and its suppression, as well as other types of instabilities and spatial patterns. It includes problems and worked-out solutions for the respective chapters, giving readers ample opportunity to apply the theory to practical situations and to deepen their understandi...

The Influence of Psychological Mechanisms on Intergroup Adaptation as a Resource for Corporate Management and Organizational Changes

Directory of Open Access Journals (Sweden)

Bulgacov Aleksandr

2017-01-01

Full Text Available In the article, the author provides the findings of the empiric study, involving the employees of construction companies, with account for their diverse social statuses. Top executives, directors of departments, and engineers participated in the research project, covered by the article. One hundred and forty employees of six construction companies were involved in the empiric study. The project comprises quantitative and qualitative correlation of management situations, based on the methodology, developed by D. Snowden; contributions made by the psychological mechanisms of intergroup adaptation, as well as the resolution of management situations. The findings have proven that by getting adjusted to versa-tile management situations, group members alter the motivation potential of their groups by urging other groups, interacting with theirs, to get adjusted to the new environment of social interaction. Therefore, the difference in the motivation potentials of interacting groups may cause the resonance, leading to constructive solutions.

Systems of Interaction between the First Sedentary Villages in the Near East Exposed Using Agent-Based Modelling of Obsidian Exchange

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David Ortega

2016-03-01

Full Text Available In the Near East, nomadic hunter-gatherer societies became sedentary farmers for the first time during the transition into the Neolithic. Sedentary life presented a risk of isolation for Neolithic groups. As fluid intergroup interactions are crucial for the sharing of information, resources and genes, Neolithic villages developed a network of contacts. In this paper we study obsidian exchange between Neolithic villages in order to characterize this network of interaction. Using agent-based modelling and elements taken from complex network theory, we model obsidian exchange and compare results with archaeological data. We demonstrate that complex networks of interaction were established at the outset of the Neolithic and hypothesize that the existence of these complex networks was a necessary condition for the success and spread of a new way of living.

Linguistic Barriers and Bridges

DEFF Research Database (Denmark)

Thuesen, Frederik

2016-01-01

The influence of language on social capital in low-skill and ethnically diverse workplaces has thus far received very limited attention within the sociology of work. As the ethnically diverse workplace is an important social space for the construction of social relations bridging different social...... groups, the sociology of work needs to develop a better understanding of the way in which linguistic diversity influences the formation of social capital, i.e. resources such as the trust and reciprocity inherent in social relations in such workplaces. Drawing on theories about intergroup contact...... and intercultural communication, this article analyses interviews with 31 employees from two highly ethnically diverse Danish workplaces. The article shows how linguistic barriers such as different levels of majority language competence and their consequent misunderstandings breed mistrust and hostility, whilst...

Ethnic diversity and personal contact at work and school in the Netherlands: a comparison of natives and ethnic minorities

NARCIS (Netherlands)

Huijts, T.; Sluiter, R.; Scheepers, P.; Kraaykamp, G.

2014-01-01

We examined to what extent ethnic diversity in neighborhoods and municipalities in the Netherlands is related to personal contacts at work and at school with the ethnic in- and out-groups, among the native majority as well as ethnic minorities. Constrict theory, ethnic competition theory, and

Some recent advances in 3D crack and contact analysis of elastic solids with transverse isotropy and multifield coupling

Science.gov (United States)

Chen, Wei-Qiu

2015-10-01

Significant progress has been made in mixed boundary-value problems associated with three-dimensional (3D) crack and contact analyses of advanced materials featuring more complexities compared to the conventional isotropic elastic materials. These include material anisotropy and multifield coupling, two typical characteristics of most current multifunctional materials. In this paper we try to present a state-of-the-art description of 3D exact/analytical solutions derived for crack and contact problems of elastic solids with both transverse isotropy and multifield coupling in the latest decade by the potential theory method in the spirit of V. I. Fabrikant, whose ingenious breakthrough brings new vigor and vitality to the old research subject of classical potential theory. We are particularly interested in crack and contact problems with certain nonlinear features. Emphasis is also placed on the coupling between the temperature field (or the like) and other physical fields (e.g., elastic, electric, and magnetic fields). We further highlight the practical significance of 3D contact solutions, in particular in applications related to modern scanning probe microscopes.

Analysis of Wetting and Contact Angle Hysteresis on Chemically Patterned Surfaces

KAUST Repository

Xu, Xianmin; Wang, Xiaoping

2011-01-01

Wetting and contact angle hysteresis on chemically patterned surfaces in two dimensionsare analyzed from a stationary phase-field model for immiscible two phase fluids. We first study the sharp-interface limit of the model by the method of matched asymptotic expansions. We then justify the results rigorously by the γ-convergence theory for the related variational problem and study the properties of the limiting minimizers. The results also provide a clear geometric picture of the equilibrium configuration of the interface. This enables us to explicitly calculate the total surface energy for the two phase systems on chemically patterned surfaces with simple geometries, namely the two phase flow in a channel and the drop spreading. By considering the quasi-staticmotion of the interface described by the change of volume (or volume fraction), we can follow the change-of-energy landscape which also reveals the mechanism for the stick-slip motion of the interface and contact angle hysteresis on the chemically patterned surfaces. As the interface passes throughpatterned surfaces, we observe not only stick-slip of the interface and switching of the contact angles but also the hysteresis of contact point and contact angle. Furthermore, as the size of the patternde creases to zero, the stick-slip becomes weaker but the hysteresis becomes stronger in the sense that one observes either the advancing contact angle or the receding contact angle (when the interface ismoving in the opposite direction) without the switching in between. © 2011 Society for Industrial and Applied Mathematics.

Tribology theory versus experiment

Science.gov (United States)

Ferrante, John

1987-01-01

Tribology, the study of friction and wear of materials, has achieved a new interest because of the need for energy conservation. Fundamental understanding of this field is very complex and requires a knowledge of solid-state physics, material science, chemistry, and mechanical engineering. This paper is meant to be didactic in nature and outlines some of the considerations needed for a tribology research program. The approach is first to present a simple model, a field emission tip in contact with a flat surface, in order to elucidate important considerations, such as contact area, mechanical deformations, and interfacial bonding. Then examples from illustrative experiments are presented. Finally, the current status of physical theories concerning interfacial bonding are presented.

Localization in abelian Chern-Simons theory

DEFF Research Database (Denmark)

McLellan, Brendan Donald Kenneth

2013-01-01

Chern-Simons theory on a closed contact three-manifold is studied when the Lie group for gauge transformations is compact, connected, and abelian. The abelian Chern-Simons partition function is derived using the Faddeev-Popov gauge fixing method. The partition function is then formally computed...

Allergic Contact Dermatitis

Directory of Open Access Journals (Sweden)

Meltem Önder

2009-03-01

Full Text Available Allergic contact dermatitis is the delayed type hypersensitivity reaction to exogenous agents. Allergic contact dermatitis may clinically present acutely after allergen exposure and initial sensitization in a previously sensitized individual. Acute phase is characterized by erythematous, scaly plaques. In severe cases vesiculation and bullae in exposed areas are very characteristic. Repeated or continuous exposure of sensitized individual with allergen result in chronic dermatitis. Lichenification, erythematous plaques, hyperkeratosis and fissuring may develop in chronic patients. Allergic contact dermatitis is very common dermatologic problem in dermatology daily practice. A diagnosis of contact dermatitis requires the careful consideration of patient history, physical examination and patch testing. The knowledge of the clinical features of the skin reactions to various contactans is important to make a correct diagnosis of contact dermatitis. It can be seen in every age, in children textile product, accessories and touch products are common allergens, while in adults allergic contact dermatitis may be related with topical medicaments. The contact pattern of contact dermatitis depends on fashion and local traditions as well. The localization of allergic reaction should be evaluated and patients’ occupation and hobbies should be asked. The purpose of this review is to introduce to our collaques up dated allergic contact dermatitis literatures both in Turkey and in the World.

Refusing intergroup help from the morally superior: How one group's moral superiority leads to another group's reluctance to seek their help. : How one group's moral superiority leads to another group's reluctance to seek their help

NARCIS (Netherlands)

Täuber, Susanne; van Zomeren, Martijn

We examine how group members paradoxically refuse intergroup help where they might need it most: in the moral status domain. Based on the Sacred Value Protection Model (Tetlock, 2002), we predicted and found that group members felt stronger group-based anger and a stronger motivation to reaffirm

Experimental investigation on the electrical contact behavior of rolling contact connector

Energy Technology Data Exchange (ETDEWEB)

Chen, Junxing; Yang, Fei, E-mail: yfei2007@mail.xjtu.edu.cn; Luo, Kaiyu; Zhu, Mingliang; Wu, Yi; Rong, Mingzhe [State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an 710049 (China)

2015-12-15

Rolling contact connector (RCC) is a new technology utilized in high performance electric power transfer systems with one or more rotating interfaces, such as radars, satellites, wind generators, and medical computed tomography machines. Rolling contact components are used in the RCC instead of traditional sliding contacts to transfer electrical power and/or signal. Since the requirement of the power transmission is increasing in these years, the rolling electrical contact characteristics become more and more important for the long-life design of RCC. In this paper, a typical form of RCC is presented. A series of experimental work are carried out to investigate the rolling electrical contact characteristics during its lifetime. The influence of a variety of factors on the electrical contact degradation behavior of RCC is analyzed under both vacuum and air environment. Based on the surface morphology and elemental composition changes in the contact zone, which are assessed by field emission scanning electron microscope and confocal laser scanning microscope, the mechanism of rolling electrical contact degradation is discussed.

Experimental Study of Static Contact-angle on Peak-like Microstructural Surfaces Produced by PIII Technology

Science.gov (United States)

Yang, Runhua; Yang, Lixin

2018-06-01

Plasma immersion ion implantation (PIII) was used to fabricate micro/nano structures on monocrystalline Si surfaces with different ratios of mixed gases (SF6/O2). The micro/nano structures on the surfaces of the sample were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results showed that with increasing ratio of mixed gases (SF6/O2), the height of the micro/nano structures first increased and then decreased. Contact-angle measurements indicated that the surfaces' micro/nano structures have an obvious effect on the contact-angle, and could cause a change in surface wettability. The theoretical analysis of contact-angle showed that the Wenzel and Cassie theories cannot predict the contact-angle of a roughened surface accurately, and should be corrected for practical applications using an actual model. Moreover, the contact-angle first increased and then decreased with increasing ratio of mixed gases (SF6/O2), which is in accordance with the change of the height of micro/nano structures.

String theory as a Lilliputian world

International Nuclear Information System (INIS)

Ambjørn, J.; Makeenko, Y.

2016-01-01

Lattice regularizations of the bosonic string do not allow us to probe the tachyon. This has often been viewed as the reason why these theories have never managed to make any contact to standard continuum string theories when the dimension of spacetime is larger than two. We study the continuum string theory in large spacetime dimensions where simple mean field theory is reliable. By keeping carefully the cutoff we show that precisely the existence of a tachyon makes it possible to take a scaling limit which reproduces the lattice-string results. We compare this scaling limit with another scaling limit which reproduces standard continuum-string results. If the people working with lattice regularizations of string theories are akin to Gulliver they will view the standard string-world as a Lilliputian world no larger than a few lattice spacings.

String theory as a Lilliputian world

Energy Technology Data Exchange (ETDEWEB)

Ambjørn, J., E-mail: ambjorn@nbi.dk [The Niels Bohr Institute, Copenhagen University, Blegdamsvej 17, DK-2100 Copenhagen (Denmark); IMAPP, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen (Netherlands); Makeenko, Y., E-mail: makeenko@nbi.dk [The Niels Bohr Institute, Copenhagen University, Blegdamsvej 17, DK-2100 Copenhagen (Denmark); Institute of Theoretical and Experimental Physics, B. Cheremushkinskaya 25, 117218 Moscow (Russian Federation)

2016-05-10

Lattice regularizations of the bosonic string do not allow us to probe the tachyon. This has often been viewed as the reason why these theories have never managed to make any contact to standard continuum string theories when the dimension of spacetime is larger than two. We study the continuum string theory in large spacetime dimensions where simple mean field theory is reliable. By keeping carefully the cutoff we show that precisely the existence of a tachyon makes it possible to take a scaling limit which reproduces the lattice-string results. We compare this scaling limit with another scaling limit which reproduces standard continuum-string results. If the people working with lattice regularizations of string theories are akin to Gulliver they will view the standard string-world as a Lilliputian world no larger than a few lattice spacings.

CONTACT RESISTANCE MODELING

Directory of Open Access Journals (Sweden)

S. V. LOSKUTOV

2018-05-01

Full Text Available Purpose. To determine the contribution of the real contact spots distribution in the total conductivity of the conductors contact. Methodology. The electrical contact resistance research was carried out on models. The experimental part of this work was done on paper with a graphite layer with membranes (the first type and conductive liquids with discrete partitions (the second type. Findings. It is shown that the contact electrical resistance is mainly determined by the real area of metal contact. The experimental dependence of the electrical resistance of the second type model on the distance between the electrodes and the potential distribution along the sample surface for the first type model were obtained. The theoretical model based on the principle of electric field superposition was considered. The dependences obtained experimentally and calculated by using the theoretical model are in good agreement. Originality. The regularity of the electrical contact resistance formation on a large number of membranes was researched for the first time. A new model of discrete electrical contact based on the liquid as the conducting environment with nuclear membrane partitions was developed. The conclusions of the additivity of contact and bulk electrical resistance were done. Practical value. Based on these researches, a new experimental method of kinetic macroidentation that as a parameter of the metal surface layer deformation uses the real contact area was developed. This method allows to determine the value of average contact stresses, yield point, change of the stress on the depth of deformation depending on the surface treatment.

Hysteresis of Contact Angle of Sessile Droplets on Smooth Homogeneous Solid Substrates via Disjoining/Conjoining Pressure.

Science.gov (United States)

Kuchin, I; Starov, V

2015-05-19

A theory of contact angle hysteresis of liquid droplets on smooth, homogeneous solid substrates is developed in terms of the shape of the disjoining/conjoining pressure isotherm and quasi-equilibrium phenomena. It is shown that all contact angles, θ, in the range θr contact angle θ ≠ θe, correspond to the state of slow "microscopic" advancing or receding motion of the liquid if θe contact angle reaches the critical values θa or θr, correspondingly. The values of the static receding, θr, and static advancing, θa, contact angles in cylindrical capillaries were calculated earlier, based on the shape of disjoining/conjoining pressure isotherm. It is shown now that (i) both advancing and receding contact angles of a droplet on a on smooth, homogeneous solid substrate can be calculated based on shape of disjoining/conjoining pressure isotherm, and (ii) both advancing and receding contact angles depend on the drop volume and are not unique characteristics of the liquid-solid system. The latter is different from advancing/receding contact angles in thin capillaries. It is shown also that the receding contact angle is much closer to the equilibrium contact angle than the advancing contact angle. The latter conclusion is unexpected and is in a contradiction with the commonly accepted view that the advancing contact angle can be taken as the first approximation for the equilibrium contact angle. The dependency of hysteresis contact angles on the drop volume has a direct experimental confirmation.

Supporting Interethnic and Interracial Friendships among Youth to Reduce Prejudice and Racism in Schools: The Role of the School Counselor

Science.gov (United States)

Pica-Smith, Cinzia; Poynton, Timothy A.

2015-01-01

Supporting interethnic and interracial friendships in schools among children and adolescents is an important part of a progressive educational agenda informed in equity, social justice frameworks, and critical multicultural education that leads to a reduction in racial prejudice. Positive intergroup contact is a necessary condition in prejudice…

Current knowledge on biomarkers for contact sensitization and allergic contact dermatitis

DEFF Research Database (Denmark)

Koppes, Sjors A.; Engebretsen, Kristiane A.; Agner, Tove

2017-01-01

Contact sensitization is common and affects up to 20% of the general population. The clinical manifestation of contact sensitization is allergic contact dermatitis. This is a clinical expression that is sometimes difficult to distinguish from other types of dermatitis, for example irritant...... and atopic dermatitis. Several studies have examined the pathogenesis and severity of allergic contact dermatitis by measuring the absence or presence of various biomarkers. In this review, we provide a non-systematic overview of biomarkers that have been studied in allergic contact dermatitis. These include...... genetic variations and mutations, inflammatory mediators, alarmins, proteases, immunoproteomics, lipids, natural moisturizing factors, tight junctions, and antimicrobial peptides. We conclude that, despite the enormous amount of data, convincing specific biomarkers for allergic contact dermatitis are yet...

Coordinate transformation in the model of long Josephson contacts: geometrically equivalent contacts

International Nuclear Information System (INIS)

Semerdzhieva, E.G.; Boyadzhiev, T.L.; ); Shukrinov, Yu.M.; Physical Technical Institute Dushanbe, 734063

2005-01-01

The transition from model of long Josephson variable-width contact to the contact model with coordinate-dependent Josephson current amplitude is realized by transforming the coordinates. This sets up a correspondence between Josephson contacts of variable width and quasi-one-dimensional contacts of variable thickness barrier layer. It is shown, that for contacts of exponentially varying width the barrier layer of the corresponding quasi-one-dimensional contact contains the distributed resistive inhomogeneity which is an attractor to magnetic flux vortices. With numerical experiments, a 'critical current-magnetic field' dependence for a resistive microinhomogeneity Josephson contact was plotted, and its comparison with the critical curve for a contact of exponentially varying width was made. Thus, this demonstrates that the distributed inhomogeneity may be replaced by a local one at the JC end what technologically, may offer definite advantages

Belief in the malleability of groups strengthens the tenuous link between a collective apology and intergroup forgiveness.

Science.gov (United States)

Wohl, Michael J A; Cohen-Chen, Smadar; Halperin, Eran; Caouette, Julie; Hayes, Nicole; Hornsey, Matthew J

2015-05-01

Although it is widely assumed that collective apologies for intergroup harms facilitate forgiveness, evidence for a strong link between the two remains elusive. In four studies we tested the proposition that the apology-forgiveness link exists, but only among people who hold an implicit belief that groups can change. In Studies 1 and 2, perceived group malleability (measured and manipulated, respectively) moderated the responses to an apology by Palestinian leadership toward Israelis: Positive responses such as forgiveness increased with greater belief in group malleability. In Study 3, university students who believed in group malleability were more forgiving of a rival university's derogatory comments in the presence (as opposed to the absence) of an apology. In Study 4, perceived perpetrator group remorse mediated the moderating effect of group malleability on the apology-forgiveness link (assessed in the context of a corporate transgression). Implications for collective apologies and movement toward reconciliation are discussed. © 2015 by the Society for Personality and Social Psychology, Inc.

Radiographic appearance of Ewing sarcoma of the hands and feet: report from the Intergroup Ewing Sarcoma Study

International Nuclear Information System (INIS)

Reinus, W.R.; Gilula, L.A.; Shirley, S.K.; Askin, F.B.; Siegal, G.P.

1985-01-01

Review of current data from the Intergroup Ewing Sarcoma Study (IESS) shows that Ewing sarcoma is rare in bones of the hands and feet. The 12 patients from the IESS protocols with hand or foot Ewing sarcoma are comparable to those already reported in the literature. With the exception of lesions in the calcaneus, the prognosis for disease-free survival is excellent. The radiographic features of hand and foot Ewing sarcoma are generally those of classic Ewing sarcoma: permeation, soft-tissue mass, and often, associated sclerotic reaction. However, with the exception of sclerosis, features suggesting bone reaction and slow tumor growth in these patients were distinctly uncommon compared with Ewing sarcoma in general. Apparently location of the lesion is important, since in the reported cases in the literature and in this series, lesions of the calcaneus fared poorly. The importance of this set of patients therefore relates to awareness and early recognition of an unusual appearance and location of Ewing sarcoma

Simulation Results: Optimization of Contact Ratio for Interdigitated Back-Contact Solar Cells

Directory of Open Access Journals (Sweden)

Vinay Budhraja

2017-01-01

Full Text Available In the fabrication of interdigitated back contact (IBC solar cells, it is very important to choose the right size of contact to achieve the maximum efficiency. Line contacts and point contacts are the two possibilities, which are being chosen for IBC structure. It is expected that the point contacts would give better results because of the reduced recombination rate. In this work, we are simulating the effect of contact size on the performance of IBC solar cells. Simulations were done in three dimension using Quokka, which numerically solves the charge carrier transport. Our simulation results show that around 10% of contact ratio is able to achieve optimum cell efficiency.

Contact line motion in confined liquid–gas systems: Slip versus phase transition

KAUST Repository

Xu, Xinpeng

2010-11-30

In two-phase flows, the interface intervening between the two fluid phases intersects the solid wall at the contact line. A classical problem in continuum fluid mechanics is the incompatibility between the moving contact line and the no-slip boundary condition, as the latter leads to a nonintegrable stress singularity. Recently, various diffuse-interface models have been proposed to explain the contact line motion using mechanisms missing from the sharp-interface treatments in fluid mechanics. In one-component two-phase (liquid–gas) systems, the contact line can move through the mass transport across the interface while in two-component (binary) fluids, the contact line can move through diffusive transport across the interface. While these mechanisms alone suffice to remove the stress singularity, the role of fluid slip at solid surface needs to be taken into account as well. In this paper, we apply the diffuse-interface modeling to the study of contact line motion in one-component liquid–gas systems, with the fluid slip fully taken into account. The dynamic van der Waals theory has been presented for one-component fluids, capable of describing the two-phase hydrodynamics involving the liquid–gas transition [A. Onuki, Phys. Rev. E 75, 036304 (2007)]. This theory assumes the local equilibrium condition at the solid surface for density and also the no-slip boundary condition for velocity. We use its hydrodynamicequations to describe the continuum hydrodynamics in the bulk region and derive the more general boundary conditions by introducing additional dissipative processes at the fluid–solid interface. The positive definiteness of entropy production rate is the guiding principle of our derivation. Numerical simulations based on a finite-difference algorithm have been carried out to investigate the dynamic effects of the newly derived boundary conditions, showing that the contact line can move through both phase transition and slip, with their relative

First contact diagnosis and management of contact lens-related complications.

Science.gov (United States)

Fagan, Xavier J; Jhanji, Vishal; Constantinou, Marios; Amirul Islam, F M; Taylor, Hugh R; Vajpayee, Rasik B

2012-08-01

To describe the spectrum of contact lens-related problems in cases presenting to a tertiary referral eye hospital. A retrospective case record analysis of 111 eyes of 97 consecutive patients was undertaken over a period of five months at the Royal Victorian Eye and Ear Hospital, Melbourne, Australia. Contact lens-related complications (CLRC) were classified into microbial keratitis, sterile corneal infiltrates, corneal epitheliopathy and contact lens-related red eye (CLARE). Main parameters examined were nature of the first contact, clinical diagnosis, and management pattern. Forty-two percent of the initial presentations were to health care practitioners (HCPs) other than ophthalmologists. Mean duration from the onset of symptoms to presentation was 6.3 ± 10.9 days. Forty-nine percent (n = 54) of patients had an associated risk factor, most commonly overnight use of contact lenses (n = 14, 13 %). Most common diagnosis at presentation was corneal epitheliopathy (68 %) followed by sterile infiltrates (10 %), CLARE (8 %) and microbial keratitis (6 %). No significant differences were found in the pattern of treatment modalities administered by ophthalmologists and other HCPs. HCPs other than ophthalmologists are the first contact for contact lens-related problems in a significant proportion of patients. These HCPs manage the majority of CLRC by direct treatment or immediate referral.

Experimental analysis of the Schottky barrier height of metal contacts in black phosphorus field-effect transistors

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Chang, Hsun-Ming; Fan, Kai-Lin; Charnas, Adam; Ye, Peide D.; Lin, Yu-Ming; Wu, Chih-I.; Wu, Chao-Hsin

2018-04-01

Compared to graphene and MoS2, studies on metal contacts to black phosphorus (BP) transistors are still immature. In this work, we present the experimental analysis of titanium contacts on BP based upon the theory of thermionic emssion. The Schottky barrier height (SBH) is extracted by thermionic emission methods to analyze the properties of Ti-BP contact. To examine the results, the band gap of BP is extracted followed by theoretical band alignment by Schottky-Mott rule. However, an underestimated SBH is found due to the hysteresis in electrical results. Hence, a modified SBH extraction for contact resistance that avoids the effects of hysteresis is proposed and demonstrated, showing a more accurate SBH that agrees well with theoretical value and results of transmission electron microscopy and energy-dispersive x-ray spectroscopy.

VULNERABILITY, AUTHENTICITY, AND INTER-SUBJECTIVE CONTACT: PHILOSOPHICAL PRINCIPLES OF INTEGRATIVE PSYCHOTHERAPY

OpenAIRE

Richard G. Erskine

2013-01-01

The Philosophical principles of a relationally focused Integrative Psychotherapy are described through the concepts of vulnerability, authenticity, and inter-subjective contact. Eight principles or therapist attitudes are outlined with clinical examples that illustrate the philosophy. These philosophical principles provide the foundation for a theory of methods. This article is based on a keynote address given at the 6th International Integrative Psychotherapy Association Conference, Granth...

The effects of contact with Asians and Asian Americans on White American college students: attitudes, awareness of racial discrimination, and psychological adjustment.

Science.gov (United States)

Dinh, Khanh T; Weinstein, Traci L; Nemon, Melissa; Rondeau, Sara

2008-12-01

On the basis of acculturation theory, explicating mutual influences between different cultural or ethnic groups coming into contact, this study focused "on the other side of acculturation" theory by examining the effects of intercultural contact with Asians and Asian Americans on the psychosocial experiences of White American college students. Participants (N = 315), undergraduates attending a public university located within the state of Massachusetts, completed a survey that assessed demographic and personal characteristics, acculturation (extent of intercultural contact with Asian people and Asian cultures), attitudes towards Asians and Asian Americans, awareness of institutional discrimination and blatant racial issues, and psychological distress. Results indicated that White American students' intercultural contact with Asians and Asian Americans contributed significant variance to the prediction of their attitudes towards this ethnic group and awareness of discrimination and racial issues, but not to psychological distress. This study provides implications for understanding mutual acculturative influences between different ethnic groups in the United States.

Pathways to Police Contact for Spousal Violence Survivors: The Role of Individual and Neighborhood Factors in Survivors' Reporting Behaviors.

Science.gov (United States)

Barrett, Betty Jo; Peirone, Amy; Cheung, Chi Ho; Habibov, Nazim

2017-09-01

Rational choice theory proposes that spousal violence survivors engage in a cost-benefit analysis when determining whether to contact the police in the aftermath of violence. Feminist intersectional frameworks contend that the perceived costs and benefits of police intervention differ among survivors based on their intersecting social identities. Normative theory further posits that it is not solely individual factors but also social norms derived from one's neighborhood context that may be related to reporting practices. Consistent with these perspectives, this study assessed the association between spousal violence survivors' sociodemographic, violence, and neighborhood characteristics and (a) police contact, (b) pathways to police contact, (c) motivations for contacting the police, and (d) motivations for not contacting the police. Data were drawn from the 2009 Canadian General Social Survey-Victimization main file, and included male and female survivors ( N = 890). Survivors most commonly contacted the police to stop the violence (89.4%) and most commonly did not contact the police because they did not believe it was important enough (35.3%). Results of multivariate regression analysis indicate that survivors who were visible minority, those who feared for their lives, and those who were injured were significantly more likely to self-report violence to police. Survivors were more likely to say the violence was not important enough to report if there was a police station in their neighborhood, and were less likely to say that violence was not important enough to report if they had experienced multiple incidents of violence. Implications for policing and criminal justice system engagement with spousal violence survivors are provided.

CONSIDERATIONS UPON CONTACT STRESS MODELLING IN DENTAL ARTICULATOR PAIRS

Directory of Open Access Journals (Sweden)

Carmen Ciornei

2012-05-01

Full Text Available A dental articulator is a mechanism which simulates the temporo-mandibular joint. The articulator is essential as it replicates the basic motions of the upper and lower mandibles, both revolve and translational motions. In the present paper the stresses from an articulator TMJ modelled as a bronze sphere into a cylindrical steel cavity are analyzed by two methods, first applying the Hertzian contact theory and then numerically, by means of finite element analysis using the simulation module in CATIA.

ComplexContact: a web server for inter-protein contact prediction using deep learning

KAUST Repository