Sample records for minor structures

  1. RAPID COMMUNICATION: Study of superstructure II in multiferroic BiMnO3

    NASA Astrophysics Data System (ADS)

    Ge, Bing-Hui; Li, Fang-Hua; Li, Xue-Ming; Wang, Yu-Mei; Chi, Zhen-Hua; Jin, Chang-Qing

    2008-09-01

    The crystal structure of the minor phase, named superstructure II, existing in multiferroic compound BiMnO3 has been studied by electron diffraction and high-resolution transmission electron microscopy. Domains of major and minor phases coexisting in BiMnO3 were observed in high-resolution electron microscope images. The unit cell of minor phase was determined to be triclinic with the size 4×4×4 times as large as the distorted perovskite subcell. The [111] and [10bar 1] projected structure maps of the minor phase have been derived from the corresponding images by means of the image processing. A possible rough three-dimensional (3D) structure model was proposed based on the 3D structural information extracted from the two projected structure maps. Since there is no inversion centre in the proposed model, the minor phase may contribute to the ferroelectric property of BiMnO3.

  2. Structural Stigma and Cigarette Smoking in a Prospective Cohort Study of Sexual Minority and Heterosexual Youth

    PubMed Central

    Hatzenbuehler, Mark L.; Jun, Hee-Jin; Corliss, Heather L.; Austin, S. Bryn

    2013-01-01

    Background Sexual minority youth are more likely to smoke cigarettes than heterosexuals but research into the determinants of these disparities is lacking. Purpose To examine whether exposure to structural stigma predicts cigarette smoking in sexual minority youth. Methods Prospective data from adolescents participating in the Growing Up Today Study (2000–2005). Results Among sexual minority youth, living in low structural stigma states (e.g., states with non-discrimination policies inclusive of sexual orientation) was associated with a lower risk of cigarette smoking after adjustment for individual-level risk factors (Relative Risk[RR]=0.97, 95% Confidence Interval[CI]: 0.96, 0.99, p=0.02). This association remained marginally significant after additional controls for potential state-level confounders (RR=0.97, 95% CI: 0.93, 1.00, p=0.06). In contrast, among heterosexual youth, structural stigma was not associated with past-year smoking rates, documenting specificity of these effects to sexual minority youth. Conclusions Structural stigma represents a potential risk factor for cigarette smoking among sexual minority adolescents. PMID:24136092

  3. The influence of structural stigma and rejection sensitivity on young sexual minority men's daily tobacco and alcohol use

    PubMed Central

    Pachankis, John E.; Hatzenbuehler, Mark L.; Starks, Tyrel J.

    2018-01-01

    Stigma occurs at both individual and structural levels, but existing research tends to examine the effect of individual and structural forms of stigma in isolation, rather than considering potential synergistic effects. To address this gap, our study examined whether stigma at the individual level, namely gay-related rejection sensitivity, interacts with structural stigma to predict substance use among young sexual minority men. Sexual minority (n = 119) participants completed online measures of our constructs (e.g., rejection sensitivity). Participants currently resided across a broad array of geographic areas (i.e., 24 U.S. states), and had attended high school in 28 states, allowing us to capture sufficient variance in current and past forms of structural stigma, defined as (1) a lack of state-level policies providing equal opportunities for heterosexual and sexual minority individuals and (2) negative state-aggregated attitudes toward sexual minorities. To measure daily substance use, we utilized a daily diary approach, whereby all participants were asked to indicate whether they used tobacco or alcohol on nine consecutive days. Results indicated that structural stigma interacted with rejection sensitivity to predict tobacco and alcohol use, and that this relationship depended on the developmental timing of exposure to structural stigma. In contrast, rejection sensitivity did not mediate the relationship between structural stigma and substance use. These results suggest that psychological predispositions, such as rejection sensitivity, interact with features of the social environment, such as structural stigma, to predict important health behaviors among young sexual minority men. These results add to a growing body of research documenting the multiple levels through which stigma interacts to produce negative health outcomes among sexual minority individuals. PMID:24507912

  4. Perceived Discrimination and Social Relationship Functioning among Sexual Minorities: Structural Stigma as a Moderating Factor

    PubMed Central

    Doyle, David Matthew; Molix, Lisa

    2015-01-01

    Work on structural stigma shows how public policy affects health outcomes for members of devalued groups, including sexual minorities. In the current research, structural stigma is proposed as a moderating variable that strengthens deleterious associations between perceived discrimination and social relationship functioning. Hypotheses were tested in two cross-sectional studies, including both online (N = 214; Study 1) and community (N = 94; Study 2) samples of sexual minority men and women residing throughout the United States. Structural stigma was coded from policy related to sexual minority rights within each state. Confirming hypotheses, support for the moderating role of structural stigma was found via multilevel models across studies. Specifically, associations between perceived discrimination and friendship strain, loneliness (Study 1) and familial strain (Study 2) were increased for those who resided in states with greater levels of structural stigma and attenuated for those who resided in states with lesser levels. In Study 1, these results were robust to state-level covariates (conservatism and religiosity), but conservatism emerged as a significant moderator in lieu of structural stigma in Study 2. Results are discussed in the context of the shifting landscape of public policy related to sexual minority rights within the United States. PMID:26807046

  5. Ethnic minority psychology in the 20th century: reflections and meditations on what has been and what is next.

    PubMed

    Jones, J M

    1998-01-01

    The launching of a new journal on ethnic minority psychology is placed in the context of events of the 20th century that precede it and make it possible. Citing the Dulles conference in 1978 on the role of ethnic minority issues in psychology, the author describes how the creation of the American Psychological Association (APA's) Office of Ethnic Minority Affairs and related governance structures made the creation of APA Division 45 (Society for the Psychological Study of Ethnic Minority Issues) possible, and hence their journal, Cultural Diversity and Ethnic Minority Psychology. Issues of conflict and cooperation among ethnic minority groups are discussed as the challenge to create unity from diversity is faced. Consideration of the steady increase in doctorally trained ethnic minority psychologists, relevant research, and organizational structures provides a basis for a publication outlet for these ideas. The challenges for ethnic minority psychology in the 21st century include research on the cultural diversity underlying ethnic minority groups and the similarities revealed by these differences, as well as the differences themselves. The new journal must fulfill the broad promise of the psychological study of ethnic minority issues on which Division 45 was founded.

  6. Electrical and Structural Characterization of Web Dendrite Crystals

    NASA Technical Reports Server (NTRS)

    Schwuttke, G. H.; Koliwad, K.; Dumas, K. A.

    1985-01-01

    Minority carrier lifetime distributions in silicon web dendrites are measured. Emphasis is placed on measuring areal homogeneity of lifetime, show its dependency on structural defects, and its unique change during hot processing. The internal gettering action of defect layers present in web crystals and their relation to minority carrier lifetime distributions is discussed. Minority carrier lifetime maps of web dendrites obtained before and after high temperature heat treatment are compared to similar maps obtained from 100 mm diameter Czochralski silicon wafers. Such maps indicate similar or superior areal homogeneity of minority carrier lifetime in webs.

  7. Indicators of Family and Household Structure of Racial and Ethnic Minorities in the U.S. CDE Working Paper 77-29.

    ERIC Educational Resources Information Center

    Sweet, James A.

    This paper reviews some of the issues and concerns that have prompted the growth of interest in the demography of the family. It also examines a number of aspects of the family and the household structure of racial and ethnic minorities. The five racial minorities discussed are blacks, Chinese, Japanese, Filipinos and American Indians. The…

  8. Sexual Minority Women's Satisfaction with Health Care Providers and State-level Structural Support: Investigating the Impact of Lesbian, Gay, Bisexual, and Transgender Nondiscrimination Legislation.

    PubMed

    Baldwin, Aleta M; Dodge, Brian; Schick, Vanessa; Sanders, Stephanie A; Fortenberry, J Dennis

    Structural discrimination is associated with negative health outcomes among sexual minority populations. Recent changes to state-level and national legislation provide both the opportunity and the need to further explore the impact of legislation on the health indicators of sexual minorities. Using an ecosocial theory lens, the present research addresses the relationship between structural support or discrimination and satisfaction with one's health care provider among sexual minority women. Data were drawn from an online survey of sexual minority women's health care experiences. Using the Andersen Behavioral Model of Health Services Utilization to operationalize the variables in our model, we examined the relationship between state-level nondiscrimination legislation and satisfaction with provider-a widely used measure of health care quality-through regression analysis. Participants in structurally supportive states (i.e., those with nondiscrimination legislation) were more likely to disclose their sexual identity to their providers and to report higher satisfaction with their providers. The absence of nondiscrimination legislation was associated negatively with satisfaction with providers. Results of our study show that the external environment in which sexual minority women seek health care, characterized by structural support or lack thereof, is related to perceived quality of health care. Copyright © 2017 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

  9. Anatomical study of minor alterations in neonate vocal folds.

    PubMed

    Silva, Adriano Rezende; Machado, Almiro José; Crespo, Agrício Nubiato

    2014-01-01

    Minor structural alterations of the vocal fold cover are frequent causes of voice abnormalities. They may be difficult to diagnose, and are expressed in different manners. Cases of intracordal cysts, sulcus vocalis, mucosal bridge, and laryngeal micro-diaphragm form the group of minor structural alterations of the vocal fold cover investigated in the present study. The etiopathogenesis and epidemiology of these alterations are poorly known. To evaluate the existence and anatomical characterization of minor structural alterations in the vocal folds of newborns. 56 larynxes excised from neonates of both genders were studied. They were examined fresh, or defrosted after conservation via freezing, under a microscope at magnifications of 25× and 40×. The vocal folds were inspected and palpated by two examiners, with the aim of finding minor structural alterations similar to those described classically, and other undetermined minor structural alterations. Larynges presenting abnormalities were submitted to histological examination. Six cases of abnormalities were found in different larynges: one (1.79%) compatible with a sulcus vocalis and five (8.93%) compatible with a laryngeal micro-diaphragm. No cases of cysts or mucosal bridges were found. The observed abnormalities had characteristics similar to those described in other age groups. Abnormalities similar to sulcus vocalis or micro-diaphragm may be present at birth. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  10. Effect of ethnicity on performance in a final objective structured clinical examination: qualitative and quantitative study

    PubMed Central

    Wass, Val; Roberts, Celia; Hoogenboom, Ron; Jones, Roger; Van der Vleuten, Cees

    2003-01-01

    Objective To assess the effect of ethnicity on student performance in stations assessing communication skills within an objective structured clinical examination. Design Quantitative and qualitative study. Setting A final UK clinical examination consisting of a two day objective structured clinical examination with 22 stations. Participants 82 students from ethnic minorities and 97 white students. Main outcome measures Mean scores for stations (quantitative) and observations made using discourse analysis on selected communication stations (qualitative). Results Mean performance of students from ethnic minorities was significantly lower than that of white students for stations assessing communication skills on days 1 (67.0% (SD 6.8%) and 72.3% (7.6%); P=0.001) and 2 (65.2% (6.6%) and 69.5% (6.3%); P=0.003). No examples of overt discrimination were found in 309 video recordings. Transcriptions showed subtle differences in communication styles in some students from ethnic minorities who performed poorly. Examiners' assumptions about what is good communication may have contributed to differences in grading. Conclusions There was no evidence of explicit discrimination between students from ethnic minorities and white students in the objective structured clinical examination. A small group of male students from ethnic minorities used particularly poorly rated communicative styles, and some subtle problems in assessing communication skills may have introduced bias. Tests need to reflect issues of diversity to ensure that students from ethnic minorities are not disadvantaged. What is already known on this topicUK medical schools are concerned that students from ethnic minorities may perform less well than white students in examinationsIt is important to understand whether our examination system disadvantages themWhat this study addsMean performance of students from ethnic minorities was significantly lower than that of white students in a final year objective structured clinical examinationTwo possible reasons for the difference were poor communicative performance of a small group of male students from ethnic minorities and examiners' use of a textbook patient centred notion of good communicationIssues of diversity in test construction and implementation must be addressed to ensure that students from ethnic minorities are not disadvantaged PMID:12689978

  11. Structure of A-C Type Intervariant Interface in Nonmodulated Martensite in a Ni-Mn-Ga Alloy.

    PubMed

    Ouyang, S; Yang, Y Q; Han, M; Xia, Z H; Huang, B; Luo, X; Zhao, G M; Chen, Y X

    2016-07-06

    The structure of A-C type intervariant interface in nonmodulated martensite in the Ni54Mn25Ga21 alloy was studied using high resolution transmission electron microscopy. The A-C interface is between the martensitic variants A and C, each of which has a nanoscale substructure of twin-related lamellae. According to their different thicknesses, the nanoscale lamellae in each variant can be classified into major and minor lamellae. It is the boundaries between these lamellae in different variants that constitute the A-C interface, which is thus composed of major-major, minor-minor, and major-minor lamellar boundaries. The volume fraction of the minor lamellae, λ, plays an important role in the structure of A-C interfaces. For major-major and minor-minor lamellar boundaries, they are symmetrical or asymmetrical tilt boundaries; for major-minor boundary, as λ increases, it changes from a symmetrical tilt boundary to two asymmetrical microfacets. Moreover, both lattice and misfit dislocations were observed in the A-C interfaces. On the basis of experimental observations and dislocation theory, we explain how different morphologies of the A-C interface are formed and describe the formation process of the A-C interfaces from λ ≈ 0 to λ ≈ 0.5 in terms of dislocation-boundary interaction, and we infer that low density of interfacial dislocations would lead to high mobility of the A-C interface.

  12. Development of new business opportunities for minorities in nuclear energy. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Spight, C.

    1980-12-15

    In Part I of this report the basis for the optimal development of new business opportunities for minorities in nuclear energy programs is defined within the successful completion of all contract tasks. The basis presented consists of an identification of a set of qualified minority-owned small businesses, a defined reservoir of highly trained minorities with applicable expertise, a policy context for the development of opportunities, and a proposed networking structure for information transfer/professional development. In Part II a contractor-focused analysis of the structure of the nuclear industry, a breakdown of the DOE nuclear program by region and functional area, andmore » a directory of minority-owned small businesses by region are presented.« less

  13. Deployable telescope having a thin-film mirror and metering structure

    DOEpatents

    Krumel, Leslie J [Cedar Crest, NM; Martin, Jeffrey W [Albuquerque, NM

    2010-08-24

    A deployable thin-film mirror telescope comprises a base structure and a metering structure. The base structure houses a thin-film mirror, which can be rolled for stowage and unrolled for deployment. The metering structure is coupled to the base structure and can be folded for stowage and unfolded for deployment. In the deployed state, the unrolled thin-film mirror forms a primary minor for the telescope and the unfolded metering structure positions a secondary minor for the telescope.

  14. Structural Stigma and All-Cause Mortality in Sexual Minority Populations

    PubMed Central

    Hatzenbuehler, Mark L.; Bellatorre, Anna; Lee, Yeonjin; Finch, Brian; Muennig, Peter; Fiscella, Kevin

    2013-01-01

    Stigma operates at multiple levels, including intrapersonal appraisals (e.g., self-stigma), interpersonal events (e.g., hate crimes), and structural conditions (e.g., community norms, institutional policies). Although prior research has indicated that intrapersonal and interpersonal forms of stigma negatively affect the health of the stigmatized, few studies have addressed the health consequences of exposure to structural forms of stigma. To address this gap, we investigated whether structural stigma—operationalized as living in communities with high levels of anti-gay prejudice—increases risk of premature mortality for sexual minorities. We constructed a measure capturing the average level of anti-gay prejudice at the community level, using data from the General Social Survey, which was then prospectively linked to all-cause mortality data via the National Death Index. Sexual minorities living in communities with high levels of anti-gay prejudice experienced a higher hazard of mortality than those living in low-prejudice communities (Hazard Ratio [HR] =3.03, 95% Confidence Interval [CI]=1.50, 6.13), controlling for individual and community-level covariates. This result translates into a shorter life expectancy of approximately 12 years (95% C.I.: 4-20 years) for sexual minorities living in high-prejudice communities. Analysis of specific causes of death revealed that suicide, homicide/violence, and cardiovascular diseases were substantially elevated among sexual minorities in high-prejudice communities. Strikingly, there was an 18-year difference in average age of completed suicide between sexual minorities in the high-prejudice (age 37.5) and low-prejudice (age 55.7) communities. These results highlight the importance of examining structural forms of stigma and prejudice as social determinants of health and longevity among minority populations. PMID:23830012

  15. Structural stigma and all-cause mortality in sexual minority populations.

    PubMed

    Hatzenbuehler, Mark L; Bellatorre, Anna; Lee, Yeonjin; Finch, Brian K; Muennig, Peter; Fiscella, Kevin

    2014-02-01

    Stigma operates at multiple levels, including intrapersonal appraisals (e.g., self-stigma), interpersonal events (e.g., hate crimes), and structural conditions (e.g., community norms, institutional policies). Although prior research has indicated that intrapersonal and interpersonal forms of stigma negatively affect the health of the stigmatized, few studies have addressed the health consequences of exposure to structural forms of stigma. To address this gap, we investigated whether structural stigma-operationalized as living in communities with high levels of anti-gay prejudice-increases risk of premature mortality for sexual minorities. We constructed a measure capturing the average level of anti-gay prejudice at the community level, using data from the General Social Survey, which was then prospectively linked to all-cause mortality data via the National Death Index. Sexual minorities living in communities with high levels of anti-gay prejudice experienced a higher hazard of mortality than those living in low-prejudice communities (Hazard Ratio [HR] = 3.03, 95% Confidence Interval [CI] = 1.50, 6.13), controlling for individual and community-level covariates. This result translates into a shorter life expectancy of approximately 12 years (95% C.I.: 4-20 years) for sexual minorities living in high-prejudice communities. Analysis of specific causes of death revealed that suicide, homicide/violence, and cardiovascular diseases were substantially elevated among sexual minorities in high-prejudice communities. Strikingly, there was an 18-year difference in average age of completed suicide between sexual minorities in the high-prejudice (age 37.5) and low-prejudice (age 55.7) communities. These results highlight the importance of examining structural forms of stigma and prejudice as social determinants of health and longevity among minority populations. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. The Symbolic Value and Limitations of Racial Concordance in Minority Research Engagement

    PubMed Central

    Fryer, Craig S.; Passmore, Susan R.; Maietta, Raymond C.; Petruzzelli, Jeff; Casper, Erica; Brown, Natasha A.; Butler, James; Garza, Mary A.; Thomas, Stephen B.; Quinn, Sandra C.

    2015-01-01

    The well-documented underrepresentation of racial and ethnic minorities in research demands action. The field of health disparities research, however, lacks scientific consensus about how best to respectfully recruit underrepresented minority populations in research. We explore the investigators’ perspective regarding how their own racial and ethnic background influenced their ability to recruit minorities, including 1) the influence of racial concordance (“race-matching”) in research recruitment, 2) attributes and shared values important in the development of trust with minority communities, and 3) the role self-reflection plays in the development of meaningful research relationships. In 2010, we conducted in-depth, semi-structured, telephone interviews with investigators (N=31) experienced with minority populations. Through the analysis of this coherent narrative, we uncovered both the symbolic and surface level assumptions regarding minority recruitment to expose a deep structure understanding of race, ethnicity, and social context that are critical for bridging the true social difference between researchers and participants. PMID:25769299

  17. Opportunities for healthier child feeding. Does ethnic position matter? - self-reported evaluation of family diet and impediments to change among parents with majority and minority status in Denmark.

    PubMed

    Nielsen, Annemette; Krasnik, Allan; Vassard, Ditte; Holm, Lotte

    2014-07-01

    Health inequality between ethnic groups is expressed in differences in the prevalence of diet related diseases. The aim of the study was to investigate and compare barriers toward eating healthier among ethnic majority and minority parents in Denmark. A postal survey was carried out among 2511 parents with either Danish or non-western ethnic minority descendant background, investigating barriers on cultural, structural, social, individual, and practical levels. The results showed that compared with parents of Danish origin, ethnic minority parents were more likely to evaluate their own diets negatively (OR 3.0, CI 1.7-5.3), and to evaluate their children's diets negatively (OR 4.6, CI 2.5-8.4). In addition, ethnic minority parents to a higher degree experienced barriers to eating healthier than Danish parents did. Most salient was ethnic minority parents' expression of a lack of control over their own food intake and the food given to their children in everyday life. Such a lack of control was identified on practical, social, structural and individual levels. Young age of the parents was found to explain some of the differences between ethnic groups. It is concluded that dietary interventions directed at parents of small children should address not only cultural background but also barriers operating on practical, social, structural, and individual levels, as some of these influence ethnic minorities and the majority population differently. Further exploration of the importance of young age and the interplay between structural and cultural factors in the lives of ethnic minority families is needed. Copyright © 2014. Published by Elsevier Ltd.

  18. DNA minor groove electrostatic potential: influence of sequence-specific transitions of the torsion angle gamma and deoxyribose conformations.

    PubMed

    Zhitnikova, M Y; Shestopalova, A V

    2017-11-01

    The structural adjustments of the sugar-phosphate DNA backbone (switching of the γ angle (O5'-C5'-C4'-C3') from canonical to alternative conformations and/or C2'-endo → C3'-endo transition of deoxyribose) lead to the sequence-specific changes in accessible surface area of both polar and non-polar atoms of the grooves and the polar/hydrophobic profile of the latter ones. The distribution of the minor groove electrostatic potential is likely to be changing as a result of such conformational rearrangements in sugar-phosphate DNA backbone. Our analysis of the crystal structures of the short free DNA fragments and calculation of their electrostatic potentials allowed us to determine: (1) the number of classical and alternative γ angle conformations in the free B-DNA; (2) changes in the minor groove electrostatic potential, depending on the conformation of the sugar-phosphate DNA backbone; (3) the effect of the DNA sequence on the minor groove electrostatic potential. We have demonstrated that the structural adjustments of the DNA double helix (the conformations of the sugar-phosphate backbone and the minor groove dimensions) induce changes in the distribution of the minor groove electrostatic potential and are sequence-specific. Therefore, these features of the minor groove sizes and distribution of minor groove electrostatic potential can be used as a signal for recognition of the target DNA sequence by protein in the implementation of the indirect readout mechanism.

  19. Is structural stigma's effect on the mortality of sexual minorities robust? A failure to replicate the results of a published study.

    PubMed

    Regnerus, Mark

    2017-09-01

    The study of stigma's influence on health has surged in recent years. Hatzenbuehler et al.'s (2014) study of structural stigma's effect on mortality revealed an average of 12 years' shorter life expectancy for sexual minorities who resided in communities thought to exhibit high levels of anti-gay prejudice, using data from the 1988-2002 administrations of the US General Social Survey linked to mortality outcome data in the 2008 National Death Index. In the original study, the key predictor variable (structural stigma) led to results suggesting the profound negative influence of structural stigma on the mortality of sexual minorities. Attempts to replicate the study, in order to explore alternative hypotheses, repeatedly failed to generate the original study's key finding on structural stigma. Efforts to discern the source of the disparity in results revealed complications in the multiple imputation process for missing values of the components of structural stigma. This prompted efforts at replication using 10 different imputation approaches. Efforts to replicate Hatzenbuehler et al.'s (2014) key finding on structural stigma's notable influence on the premature mortality of sexual minorities, including a more refined imputation strategy than described in the original study, failed. No data imputation approach yielded parameters that supported the original study's conclusions. Alternative hypotheses, which originally motivated the present study, revealed little new information. Ten different approaches to multiple imputation of missing data yielded none in which the effect of structural stigma on the mortality of sexual minorities was statistically significant. Minimally, the original study's structural stigma variable (and hence its key result) is so sensitive to subjective measurement decisions as to be rendered unreliable. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.

  20. Minority stress, psychosocial resources, and psychological distress among sexual minority breast cancer survivors

    PubMed Central

    Kamen, Charles; Jabson, Jennifer M.; Mustian, Karen M.; Boehmer, Ulrike

    2017-01-01

    Objective Few studies have examined unique factors predicting psychological distress among sexual minority (i.e., lesbian and bisexual) women post breast cancer diagnosis. The present study assessed the association of minority stress and psychosocial resource factors with depression and anxiety symptoms among sexual minority breast cancer survivors. Methods 201 sexual minority women who had ductal carcinoma in situ (DCIS) or stage I-IV breast cancer participated in this study through the Love/Avon Army of Women (AOW). Self-report questionnaires were used to assess demographic and clinical factors, minority stress factors (discrimination, minority identity development, outness), psychosocial resources (resilience, social support), and psychological distress (anxiety and depression). These factors were included in a structural equation model, testing psychosocial resources as mediators between minority stress and psychological distress. Results There were no significant differences noted between lesbian and bisexual women. The final structural equation model demonstrated acceptable fit across all sexual minority women, χ2 = 27.83, p > 0.05; confirmatory fit index = 0.97, root-mean-square error of approximation = 0.04, Tucker-Lewis Index = 0.93. The model accounted for significant variance in psychological distress (56%). Examination of indirect effects confirmed that exposure to discrimination was associated with distress via association with resilience. Conclusions Factors unique to sexual minority populations, such as minority stress, may be associated with higher rates of psychological distress among sexual minority breast cancer survivors. However, presence of psychosocial resources may mediate relationships with distress in this population; enhancement of resilience, in particular, could be an aim of psychological intervention. PMID:28165265

  1. Minority stress, psychosocial resources, and psychological distress among sexual minority breast cancer survivors.

    PubMed

    Kamen, Charles; Jabson, Jennifer M; Mustian, Karen M; Boehmer, Ulrike

    2017-06-01

    Few studies have examined unique factors predicting psychological distress among sexual minority (i.e., lesbian and bisexual) women postbreast cancer diagnosis. The present study assessed the association of minority stress and psychosocial resource factors with depression and anxiety symptoms among sexual minority breast cancer survivors. Two hundred one sexual minority women who had ductal carcinoma in situ or Stage I-IV breast cancer participated in this study through the Love/Avon Army of Women. Self-report questionnaires were used to assess demographic and clinical factors, minority stress factors (discrimination, minority identity development, outness), psychosocial resources (resilience, social support), and psychological distress (anxiety and depression). These factors were included in a structural equation model, testing psychosocial resources as mediators between minority stress and psychological distress. There were no significant differences noted between lesbian and bisexual women. The final structural equation model demonstrated acceptable fit across all sexual minority women, χ2 = 27.83, p > .05; confirmatory fit index = 0.97, root-mean-square error of approximation = 0.04, Tucker-Lewis index = 0.93. The model accounted for significant variance in psychological distress (56%). Examination of indirect effects confirmed that exposure to discrimination was associated with distress via association with resilience. Factors unique to sexual minority populations, such as minority stress, may be associated with higher rates of psychological distress among sexual minority breast cancer survivors. However, presence of psychosocial resources may mediate relationships with distress in this population; enhancement of resilience, in particular, could be an aim of psychological intervention. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. The organization of sex work in low and high-priced venues with a focus on the experiences of ethnic minority women working in these venues

    PubMed Central

    Qian, Liu; Zhuang, Kongshao; Henderson, Gail E.; Shenglong, Quzhen; Fang, Jingwen; Yao, Huiqin; Qin, Jingxin; Yang, Yanzhen; Abler, Laurie

    2013-01-01

    Prior research on female sex workers (FSW) in China, and their risk for HIV and STI, neglects the nuanced experiences of ethnic minority FSW. We conducted participant observations and in-depth interviews with 33 FSW and six venue bosses to describe the experiences of FSW and management structures in high and low-priced sex work venues in Liuzhou, China. In low-priced venues, FSW had more autonomy and stronger relationships with their ethnic minority peers. Mid and high-priced venues had more formal management structures. Ethnic minority FSW working in higher priced venues experienced less support and kinship with their peers. HIV/STI prevention outreach activities occurred in all of the venues, but they were not tailored for different venue types or for ethnic minority FSW. Our findings provide guidance for tailoring public health programs that meet the needs of ethnic minority women working in different types of sex work venues. PMID:23912337

  3. The organization of sex work in low- and high-priced venues with a focus on the experiences of ethnic minority women working in these venues.

    PubMed

    Liu, Qian; Zhuang, Kongshao; Henderson, Gail E; Shenglong, Quzhen; Fang, Jingwen; Yao, Huiqin; Qin, Jingxin; Yang, Yanzhen; Abler, Laurie

    2014-02-01

    Prior research on female sex workers (FSW) in China, and their risk for HIV and STI, neglects the nuanced experiences of ethnic minority FSW. We conducted participant observations and in-depth interviews with 33 FSW and six venue bosses to describe the experiences of FSW and management structures in low and high-priced sex work venues in Liuzhou, China. In low-priced venues, FSW had more autonomy and stronger relationships with their ethnic minority peers. Mid- and high-priced venues had more formal management structures. Ethnic minority FSW working in higher priced venues experienced less support and kinship with their peers. HIV/STI prevention outreach activities occurred in all of the venues, but they were not tailored for different venue types or for ethnic minority FSW. Our findings provide guidance for tailoring public health programs that meet the needs of ethnic minority women working in different types of sex work venues.

  4. Solution structure of a highly stable DNA duplex conjugated to a minor groove binder.

    PubMed Central

    Kumar, S; Reed, M W; Gamper, H B; Gorn, V V; Lukhtanov, E A; Foti, M; West, J; Meyer, R B; Schweitzer, B I

    1998-01-01

    The tripeptide 1,2-dihydro-(3 H )-pyrrolo[3,2- e ]indole-7-carboxylate (CDPI3) binds to the minor groove of DNA with high affinity. When this minor groove binder is conjugated to the 5'-end of short oligonucleotides the conjugates form unusually stable hybrids with complementary DNA and thus may have useful diagnostic and/or therapeutic applications. In order to gain an understanding of the structural interactions between the CDPI3minor groove binding moiety and the DNA, we have determined and compared the solution structure of a duplex consisting of oligodeoxyribonucleotide 5'-TGATTATCTG-3' conjugated at the 5'-end to CDPI3 and its complementary strand to an unmodified control duplex of the same sequence using nuclear magnetic resonance techniques. Thermal denaturation studies indicated that the hybrid of this conjugate with its complementary strand had a melting temperature that was 30 degrees C higher compared with the unmodified control duplex. Following restrained molecular dynamics and relaxation matrix refinement, the solution structure of the CDPI3-conjugated DNA duplex demonstrated that the overall shape of the duplex was that of a straight B-type helix and that the CDPI3moiety was bound snugly in the minor groove, where it was stabilized by extensive van der Waal's interactions. PMID:9443977

  5. Solution structure of a highly stable DNA duplex conjugated to a minor groove binder.

    PubMed

    Kumar, S; Reed, M W; Gamper, H B; Gorn, V V; Lukhtanov, E A; Foti, M; West, J; Meyer, R B; Schweitzer, B I

    1998-02-01

    The tripeptide 1,2-dihydro-(3 H )-pyrrolo[3,2- e ]indole-7-carboxylate (CDPI3) binds to the minor groove of DNA with high affinity. When this minor groove binder is conjugated to the 5'-end of short oligonucleotides the conjugates form unusually stable hybrids with complementary DNA and thus may have useful diagnostic and/or therapeutic applications. In order to gain an understanding of the structural interactions between the CDPI3minor groove binding moiety and the DNA, we have determined and compared the solution structure of a duplex consisting of oligodeoxyribonucleotide 5'-TGATTATCTG-3' conjugated at the 5'-end to CDPI3 and its complementary strand to an unmodified control duplex of the same sequence using nuclear magnetic resonance techniques. Thermal denaturation studies indicated that the hybrid of this conjugate with its complementary strand had a melting temperature that was 30 degrees C higher compared with the unmodified control duplex. Following restrained molecular dynamics and relaxation matrix refinement, the solution structure of the CDPI3-conjugated DNA duplex demonstrated that the overall shape of the duplex was that of a straight B-type helix and that the CDPI3moiety was bound snugly in the minor groove, where it was stabilized by extensive van der Waal's interactions.

  6. Cesium vacancy ordering in phase-separated C s x F e 2 - y S e 2

    DOE PAGES

    Taddei, Keith M.; Sturza, M.; Chung, Duck -Yung; ...

    2015-09-14

    By simultaneously displaying magnetism and superconductivity in a single phase, the iron-based superconductors provide a model system for the study of magnetism's role in superconductivity. The class of intercalated iron selenide superconductors is unique among these in having the additional property of phase separation and coexistence of two distinct phases—one majority phase with iron vacancy ordering and strong antiferromagnetism, and the other a poorly understood minority microscopic phase with a contested structure. Adding to the intrigue, the majority phase has never been found to show superconductivity on its own while the minority phase has never been successfully synthesized separate frommore » the majority phase. In order to better understand this minority phase, a series of high-quality Cs xFe 2–ySe 2 single crystals with (0.8 ≤ x ≤ 1;0 ≤ y ≤ 0.3) were grown and studied. Neutron and x-ray powder diffraction performed on ground crystals show that the average I4/mmm structure of the minority phase is distinctly different from the high-temperature I4/mmm parent structure. Moreover, single-crystal diffraction reveals the presence of discrete superlattice reflections that remove the degeneracy of the Cs sites in both the majority and minority phases and reduce their structural symmetries from body centered to primitive. Group theoretical analysis in conjunction with structural modeling shows that the observed superlattice reflections originate from three-dimensional Cs vacancy ordering. This model predicts a 25% vacancy of the Cs site in the minority phase which is consistent with the site's refined occupancy. Magnetization measurements performed in tandem with neutron single-crystal diffraction provide evidence that the minority phase is the host of superconductivity. Lastly, our results also reveal a superconducting dome in which the superconducting transition temperature varies as a function of the nominal valence of iron.« less

  7. Cesium vacancy ordering in phase-separated C s x F e 2 - y S e 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Taddei, K. M.; Sturza, M.; Chung, D. Y.

    2015-09-01

    By simultaneously displaying magnetism and superconductivity in a single phase, the iron based superconductors provide a model system for the study of magnetism’s role in superconductivity. The class of intercalated iron selenide superconductors is unique amongst these in having the additional property of phase separation and coexistence of two distinct phases - one majority phase with iron vacancy ordering and strong antiferromagnetism and the other a poorly understood minority microscopic phase with a contested structure. Adding to the intrigue, the majority phase has never been found to show superconductivity on its own while the minority phase has never been successfullymore » synthesized separate from the majority phase. In order to better understand this minority phase, a series of high quality CsxFe2-ySe2 single crystals with (0.8 ≤ x ≤ 1; 0 ≤ y ≤ 0.3) were grown and studied. Neutron and x-ray powder diffraction performed on ground crystals show the average structure of the minority phase to be I4/mmm, however, the temperature evolution of its lattice parameters shows it to be distinct from the high temperature I4/mmm parent structure. Neutron and x-ray diffraction experiments performed on single crystal samples reveal the presence of previously unobserved discrete superlattice reflections that remove the degeneracy of the Cs sites in both the majority and minority phases and reduce their structural symmetries from body-centered to primitive. Group theoretical analysis in conjunction with structural modeling shows that the observed superlattice reflections originate from a three-dimensional Cs vacancy ordering in the minority phase. This model predicts a 25% vacancy of the Cs site which is consistent with the site’s refined occupancy. Magnetization measurements performed in tandem with neutron single crystal diffraction provide evidence that the minority phase is the host of superconductivity. Our results also reveal a superconducting dome in which the superconducting transition temperature varies as a function of the valence of iron.« less

  8. Cardiorespiratory fitness, cognition and brain structure after TIA or minor ischemic stroke.

    PubMed

    Boss, H Myrthe; Van Schaik, Sander M; Witkamp, Theo D; Geerlings, Mirjam I; Weinstein, Henry C; Van den Berg-Vos, Renske M

    2017-10-01

    Background It is not known whether cardiorespiratory fitness is associated with better cognitive performance and brain structure in patients with a TIA or minor ischemic stroke. Aims To examine the association between cardiorespiratory fitness, cognition and brain structure in patients with a TIA and minor stroke. Methods The study population consisted of patients with a TIA or minor stroke with a baseline measurement of the peak oxygen consumption, a MRI scan of brain and neuropsychological assessment. Composite z-scores were calculated for the cognitive domains attention, memory and executive functioning. White matter hyperintensities, microbleeds and lacunes were rated visually. The mean apparent diffusion coefficient was measured in regions of interest in frontal and occipital white matter and in the centrum semiovale as a marker of white matter structure. Normalized brain volumes were estimated by use of Statistical Parametric Mapping. Results In 84 included patients, linear regression analysis adjusted for age, sex and education showed that a higher peak oxygen consumption was associated with higher cognitive z-scores, a larger grey matter volume (B = 0.15 (95% CI 0.05; 0.26)) and a lower mean apparent diffusion coefficient (B = -.004 (95% CI -.007; -.001)). We found no association between the peak oxygen consumption and severe white matter hyperintensities, microbleeds, lacunes and total brain volume. Conclusions These data suggest that cardiorespiratory fitness is associated with better cognitive performance, greater grey matter volume and greater integrity of the white matter in patients with a TIA or minor ischemic stroke. Further prospective trials are necessary to define the effect of cardiorespiratory fitness on cognition and brain structure in patients with TIA or minor stroke.

  9. Divorce, Family Structure, and the Academic Success of Children.

    ERIC Educational Resources Information Center

    Jeynes, William

    The goal of this book is to examine the relationship between parental family structure, especially parental divorce and/or remarriage, and the academic achievement of children. Much has been written about the need to raise the academic achievement of students from minority backgrounds. However, minority is often defined in terms of skin color and…

  10. New Minority Teachers' Perceptions of Teaching.

    ERIC Educational Resources Information Center

    Stallworth, B. Joyce

    This study was a follow-up investigation of five minority first-year teachers who were 1992 graduates of the Peabody Internship/Induction Teaching Program. The study was designed to examine the socialization of new minority group teachers. Structured interview protocols for the teachers and their principals were the primary means of data…

  11. Validation of the internalization of the Model Minority Myth Measure (IM-4) and its link to academic performance and psychological adjustment among Asian American adolescents.

    PubMed

    Yoo, Hyung Chol; Miller, Matthew J; Yip, Pansy

    2015-04-01

    There is limited research examining psychological correlates of a uniquely racialized experience of the model minority stereotype faced by Asian Americans. The present study examined the factor structure and fit of the only published measure of the internalization of the model minority myth, the Internalization of the Model Minority Myth Measure (IM-4; Yoo et al., 2010), with a sample of 155 Asian American high school adolescents. We also examined the link between internalization of the model minority myth types (i.e., myth associated with achievement and myth associated with unrestricted mobility) and psychological adjustment (i.e., affective distress, somatic distress, performance difficulty, academic expectations stress), and the potential moderating effect of academic performance (cumulative grade point average). Results suggested the 2-factor model of the IM-4 had an acceptable fit to the data and supported the factor structure using confirmatory factor analyses. Internalizing the model minority myth of achievement related positively to academic expectations stress; however, internalizing the model minority myth of unrestricted mobility related negatively to academic expectations stress, both controlling for gender and academic performance. Finally, academic performance moderated the model minority myth associated with unrestricted mobility and affective distress link and the model minority myth associated with achievement and performance difficulty link. These findings highlight the complex ways in which the model minority myth relates to psychological outcomes. (c) 2015 APA, all rights reserved).

  12. Non-triglyceride components modulate the fat crystal network of palm kernel oil and coconut oil.

    PubMed

    Chai, Xiuhang; Meng, Zong; Jiang, Jiang; Cao, Peirang; Liang, Xinyu; Piatko, Michael; Campbell, Shawn; Lo, Seong Koon; Liu, Yuanfa

    2018-03-01

    PKO and CNO are composed of 97-98% triacylglycerols and 2-3% minor non-triglyceride components (FFA, DAG and MAG). Triglycerides were separated from minor components by chromatographic method. The lipid composition, thermal properties, polymorphism, isothermal crystallization behavior, nanostructure and microstructure of PKO, PKO-TAG, CNO and CNO-TAG were evaluated. Removal of minor components had no effect on lipid composition and equilibrium solid fat contents. However, presence of minor components did increase the slip melting point and promoted the onset of crystallization from DSC crystallization profiles. The thickness of the nanoscale crystals increased with no polymorphic transformation after removing the minor components. Crystallization kinetics revealed that minor components decreased crystal growth rate with higher t 1/2 . Sharp changes in the values of the Avrami constant k and exponent n were observed for all fats around 10°C. Increases in n around 10°C indicated a change from one-dimensional to multi-dimensional growth . From the results of polarized light micrographs, the transformation from the coarser crystal structure to tiny crystal structure occurred in microstructure networks at the action of minor components. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Functional and Structural Consequence of Rare Exonic Single Nucleotide Polymorphisms: One Story, Two Tales

    PubMed Central

    Gu, Wanjun; Gurguis, Christopher I.; Zhou, Jin J.; Zhu, Yihua; Ko, Eun-A.; Ko, Jae-Hong; Wang, Ting; Zhou, Tong

    2015-01-01

    Genetic variation arising from single nucleotide polymorphisms (SNPs) is ubiquitously found among human populations. While disease-causing variants are known in some cases, identifying functional or causative variants for most human diseases remains a challenging task. Rare SNPs, rather than common ones, are thought to be more important in the pathology of most human diseases. We propose that rare SNPs should be divided into two categories dependent on whether the minor alleles are derived or ancestral. Derived alleles are less likely to have been purified by evolutionary processes and may be more likely to induce deleterious effects. We therefore hypothesized that the rare SNPs with derived minor alleles would be more important for human diseases and predicted that these variants would have larger functional or structural consequences relative to the rare variants for which the minor alleles are ancestral. We systematically investigated the consequences of the exonic SNPs on protein function, mRNA structure, and translation. We found that the functional and structural consequences are more significant for the rare exonic variants for which the minor alleles are derived. However, this pattern is reversed when the minor alleles are ancestral. Thus, the rare exonic SNPs with derived minor alleles are more likely to be deleterious. Age estimation of rare SNPs confirms that these potentially deleterious SNPs are recently evolved in the human population. These results have important implications for understanding the function of genetic variations in human exonic regions and for prioritizing functional SNPs in genome-wide association studies of human diseases. PMID:26454016

  14. In-situ crystal structure determination of seifertite SiO 2 at 129 GPa: Studying a minor phase near Earth’s core–mantle boundary

    DOE PAGES

    Zhang, Li; Popov, Dmitry; Meng, Yue; ...

    2016-01-01

    Seifertite SiO₂ likely exists as a minor phase near the core–mantle boundary. By simulating the pressure and temperature conditions near the core–mantle boundary, seifertite was synthesized as a minor phase in a coarse-grained, polycrystalline sample coexisting with the (Mg,Fe)SiO₃ post-perovskite (pPv) phase at 129 GPa and 2500 K. Here we report the first in situ single-crystal structure determination and refinement of seifertite at high pressure and after a temperature quench from laser heating. We improved the data coverage of a minor phase from a diamond-anvil cell (DAC) by merging single-crystal data of seifertite from six selected grains that had differentmore » orientations. Observed systematic absences of reflections from the six individual grains allowed only one space group: Pbcn. The refined results of seifertite are in good agreement with the predictions from previous first-principles calculations at high pressure. This approach provides a method for structure determination of a minor phase in a mineral assemblage synthesized under P-T conditions representative of the deep Earth.« less

  15. In-situ crystal structure determination of seifertite SiO 2 at 129 GPa: Studying a minor phase near Earth’s core–mantle boundary

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Li; Popov, Dmitry; Meng, Yue

    Seifertite SiO₂ likely exists as a minor phase near the core–mantle boundary. By simulating the pressure and temperature conditions near the core–mantle boundary, seifertite was synthesized as a minor phase in a coarse-grained, polycrystalline sample coexisting with the (Mg,Fe)SiO₃ post-perovskite (pPv) phase at 129 GPa and 2500 K. Here we report the first in situ single-crystal structure determination and refinement of seifertite at high pressure and after a temperature quench from laser heating. We improved the data coverage of a minor phase from a diamond-anvil cell (DAC) by merging single-crystal data of seifertite from six selected grains that had differentmore » orientations. Observed systematic absences of reflections from the six individual grains allowed only one space group: Pbcn. The refined results of seifertite are in good agreement with the predictions from previous first-principles calculations at high pressure. This approach provides a method for structure determination of a minor phase in a mineral assemblage synthesized under P-T conditions representative of the deep Earth.« less

  16. Validation of the Parenting Stress Index--Short Form with Minority Caregivers

    ERIC Educational Resources Information Center

    Lee, Sang Jung; Gopalan, Geetha; Harrington, Donna

    2016-01-01

    Objectives: There has been little examination of the structural validity of the Parenting Stress Index--Short Form (PSI-SF) for minority populations in clinical contexts in the Unites States. This study aimed to test prespecified factor structures (one-factor, two-factor, and three-factor models) of the PSI-SF. Methods: This study used…

  17. Unraveling the "Model Minority" Stereotype: Listening to Asian American Youth.

    ERIC Educational Resources Information Center

    Lee, Stacey J.

    The model minority image of Asian Americans authorizes the flat denial of racism and structures of racial dominance and silences those who are not economically successful. This book explores how young people incorporate, interpret, and make meaning of the "model minority" stereotype in the context of their lived experience in school and…

  18. The Child and Adolescent Mental Health Studies (CAMS) Minor at New York University

    ERIC Educational Resources Information Center

    Shatkin, Jess P.; Koplewicz, Harold S.

    2008-01-01

    Objective: The authors describe the Child and Adolescent Mental Health Studies (CAMS) undergraduate college minor at New York University. Methods: The authors detail the development, structure, and operation of the CAMS minor. They describe the importance of identifying program goals, building coalitions, creating an advisory board, selecting…

  19. Structural analysis of the binding modes of minor groove ligands comprised of disubstituted benzenes

    PubMed Central

    Hawkins, Cheryl A.; Watson, Charles; Yan, Yinfa; Gong, Bing; Wemmer, David E.

    2001-01-01

    Two-dimensional homonuclear NMR was used to characterize synthetic DNA minor groove-binding ligands in complexes with oligonucleotides containing three different A-T binding sites. The three ligands studied have a C2 axis of symmetry and have the same general structural motif of a central para-substituted benzene ring flanked by two meta-substituted rings, giving the molecules a crescent shape. As with other ligands of this shape, specificity seems to arise from a tight fit in the narrow minor groove of the preferred A-T-rich sequences. We found that these ligands slide between binding subsites, behavior attributed to the fact that all of the amide protons in the ligand backbone cannot hydrogen bond to the minor groove simultaneously. PMID:11160926

  20. Hydrodynamics of the double-wave structure of insect spermatozoa flagella

    PubMed Central

    Pak, On Shun; Spagnolie, Saverio E.; Lauga, Eric

    2012-01-01

    In addition to conventional planar and helical flagellar waves, insect sperm flagella have also been observed to display a double-wave structure characterized by the presence of two superimposed helical waves. In this paper, we present a hydrodynamic investigation of the locomotion of insect spermatozoa exhibiting the double-wave structure, idealized here as superhelical waves. Resolving the hydrodynamic interactions with a non-local slender body theory, we predict the swimming kinematics of these superhelical swimmers based on experimentally collected geometric and kinematic data. Our consideration provides insight into the relative contributions of the major and minor helical waves to swimming; namely, propulsion is owing primarily to the minor wave, with negligible contribution from the major wave. We also explore the dependence of the propulsion speed on geometric and kinematic parameters, revealing counterintuitive results, particularly for the case when the minor and major helical structures are of opposite chirality. PMID:22298815

  1. Structure, Function and Epitope Mapping the Peanut Panallergen Ara h 8

    USDA-ARS?s Scientific Manuscript database

    The incidence of peanut allergy continues to rise in the US and Europe. Whereas exposure to the major allergens Ara h 1, 2, 3, and 6 can cause fatal anaphylaxis, exposure to the minor allergens usually does not. Ara h 8 is a minor allergen. Importantly, it is the minor food allergens that are though...

  2. Structure and function of the peanut panallergen Ara h 8

    USDA-ARS?s Scientific Manuscript database

    The incidence of peanut allergy continues to rise in the US and Europe; whereas, exposure to the major allergens Ara h 1, 2, 3, and 6 can cause fatal anaphylaxis, exposure to the minor allergens usually does not. Ara h 8 is a minor allergen. Importantly, it is the minor food allergens that are tho...

  3. [The organizational aspects of treating light casualties in modern warfare (2)].

    PubMed

    Nechaev, E A; Maksimov, G K; Agapov, V K; Golov, Iu S

    1993-07-01

    The experience gathered by Medical Service during the war in Afghanistan and during liquidation of the consequences of various disasters and accidents has shown that the most rational method of treatment of minor wounded near the combat area or zone of disaster was a two-staged (and sometimes a three-staged) management system. At the combat tactical zone it is expedient to render the secondary surgical care and reanimation procedures of vital cases, and also provide treatment of minor wounded who could be returned to their ranks in 10 days. For this purpose it is necessary to integrate the sections of medical triage and minor wounded treatment into organic structure of the Brigade medical company and Divisional hospital. As for Army Medical Brigade it must have in its structure a hospital for minor wounded who could be returned to their ranks in 20 days. All the wounded who have to be treated more than 20 days must be evacuated to the Front hospital for minor wounded.

  4. Cytology of the minor-vein phloem in 320 species from the subclass Asteridae suggests a high diversity of phloem-loading modes†

    PubMed Central

    Batashev, Denis R.; Pakhomova, Marina V.; Razumovskaya, Anna V.; Voitsekhovskaja, Olga V.; Gamalei, Yuri V.

    2013-01-01

    The discovery of abundant plasmodesmata at the bundle sheath/phloem interface in Oleaceae (Gamalei, 1974) and Cucurbitaceae (Turgeon et al., 1975) raised the questions as to whether these plasmodesmata are functional in phloem loading and how widespread symplasmic loading would be. Analysis of over 800 dicot species allowed the definition of “open” and “closed” types of the minor vein phloem depending on the abundance of plasmodesmata between companion cells and bundle sheath (Gamalei, 1989, 1990). These types corresponded to potential symplasmic and apoplasmic phloem loaders, respectively; however, this definition covered a spectrum of diverse structures of phloem endings. Here, a review of detailed cytological analyses of minor veins in 320 species from the subclass Asteridae is presented, including data on companion cell types and their combinations which have not been reported previously. The percentage of Asteridae species with “open” minor vein cytology which also contain sieve-element-companion cell complexes with “closed” cytology, i.e., that show specialization for both symplasmic and apoplasmic phloem loading, was determined. Along with recent data confirming the dissimilar functional specialization of structurally different parts of minor vein phloem in the stachyose-translocating species Alonsoa meridionalis (Voitsekhovskaja et al., 2009), these findings suggest that apoplasmic loading is indispensable in a large group of species previously classified as putative symplasmic loaders. Altogether, this study provides formal classifications of companion cells and of minor veins, respectively, in 24 families of the Asteridae based on their structural features, opening the way to a close investigation of the relationship between structure and function in phloem loading. PMID:23970890

  5. When the Minority Thinks “Essentially” Like the Majority: Blacks Distinguish Bio-Somatic from Bio-Behavioral Essentialism in Their Conceptions of Whites, and Only the Latter Predicts Prejudice

    PubMed Central

    Gill, Michael J.; Mendes, Dana M.

    2016-01-01

    Essentialist beliefs about social groups can contribute to prejudice and intergroup distancing. To date, little data have been gathered regarding minority group members’ essentialistic thinking about the White majority in the U.S. Do essentialist beliefs show a similar structure when minority group members are thinking about the majority as when the majority group is thinking about the minority group? Do minority group essentialist beliefs predict affective prejudice and diminished desire for intergroup contact as they do among White respondents? We sought answers to these questions in a study that included 248 African American participants. We found clear evidence that the structure of Blacks’ essentialist thinking about Whites matches the structure of Whites’ essentialist thinking about Blacks. Specifically, Black respondents made a distinction between bio-somatic and bio-behavioral essentialism, and reported stronger endorsement of the former as compared to the latter. Also replicating prior studies of Whites’ essentialist thinking, only bio-behavioral essentialist beliefs were predictive of negative attitudes. This suggests that essentialism can be linked to prejudice even in contexts that do not involve a dominant group rationalizing its social advantages. Discussion centers on implications of this work for prejudice reduction. PMID:27489948

  6. The Influence of Family Structure on Sexual Activity in a Randomized Effectiveness Trial for Minority Youth

    ERIC Educational Resources Information Center

    Sherr, Michael E.; Crow, Janet; Stamey, James; Jones, Johnny; Dyer, Preston

    2012-01-01

    This study examined the influence of family structure on the outcomes of a sex education program in Miami, Florida. Using an experimental design, data collection occurred at pretest, 3-month, and 6-month follow-up with a sample of teenagers from high schools with a large majority of minority youth, assigned into treatment (n = 549) and control (n…

  7. Commitment to minority inclusion: a study of AAMFT conference program content and members' perceptions.

    PubMed

    Killian, K D; Hardy, K V

    1998-04-01

    This study examined the representation of minorities and minority issues in the American Association for Marriage and Family Therapy. The relationship between AAMFT conference program content and changing social demographics from 1980 to 1996 was explored through an ecosystemic lens, and descriptive data were elicited through structured interviews with clinical members. Results indicated that there was a significant increase in the percentage of programming devoted to minority issues from 1980 to 1996 while the percentage of minorities in the population also rose dramatically in the same period. Salient themes from the interviews are presented. Recommendations are made for enhancing diversity within AAMFT.

  8. Concealing Concealment: The Mediating Role of Internalized Heterosexism in Psychological Distress Among Lesbian, Gay, and Bisexual Older Adults

    PubMed Central

    Hoy-Ellis, Charles P.

    2016-01-01

    Recent population-based studies indicate that sexual minorities aged 50 and older experience significantly higher rates of psychological distress than their heterosexual age-peers. The minority stress model has been useful in explaining disparately high rates of psychological distress among younger sexual minorities. The purpose of this study is to test a hypothesized structural relationship between two minority stressors—internalized heterosexism and concealment of sexual orientation—and consequent psychological distress among a sample of 2,349 lesbian, gay, and bisexual adults aged 50 to 95 years old. Structural equation modeling indicates that concealment has a nonsignificant direct effect on psychological distress but a significant indirect effect that is mediated through internalized heterosexism; the effect of concealment is itself concealed. This may explain divergent results regarding the role of concealment in psychological distress in other studies, and the implications will be discussed. PMID:26322654

  9. NMR studies of DNA oligomers and their interactions with minor groove binding ligands

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fagan, Patricia A.

    1996-05-01

    The cationic peptide ligands distamycin and netropsin bind noncovalently to the minor groove of DNA. The binding site, orientation, stoichiometry, and qualitative affinity of distamycin binding to several short DNA oligomers were investigated by NMR spectroscopy. The oligomers studied contain A,T-rich or I,C-rich binding sites, where I = 2-desaminodeoxyguanosine. I•C base pairs are functional analogs of A•T base pairs in the minor groove. The different behaviors exhibited by distamycin and netropsin binding to various DNA sequences suggested that these ligands are sensitive probes of DNA structure. For sites of five or more base pairs, distamycin can form 1:1 or 2:1more » ligand:DNA complexes. Cooperativity in distamycin binding is low in sites such as AAAAA which has narrow minor grooves, and is higher in sites with wider minor grooves such as ATATAT. The distamycin binding and base pair opening lifetimes of I,C-containing DNA oligomers suggest that the I,C minor groove is structurally different from the A,T minor groove. Molecules which direct chemistry to a specific DNA sequence could be used as antiviral compounds, diagnostic probes, or molecular biology tools. The author studied two ligands in which reactive groups were tethered to a distamycin to increase the sequence specificity of the reactive agent.« less

  10. Final Report: An Undergraduate Minor in Wind Energy at Iowa State University

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    James McCalley

    This report describes an undergraduate minor program in wind energy that has been developed at Iowa State University. The minor program targets engineering and meteorology students and was developed to provide interested students with focused technical expertise in wind energy science and engineering, to increase their employability and ultimate effectiveness in this growing industry. The report describes the requirements of the minor program and courses that fulfill those requirements. Five new courses directly addressing wind energy have been developed. Topical descriptions for these five courses are provided in this report. Six industry experts in various aspects of wind energy sciencemore » and engineering reviewed the wind energy minor program and provided detailed comments on the program structure, the content of the courses, and the employability in the wind energy industry of students who complete the program. The general consensus is that the program is well structured, the course content is highly relevant, and students who complete it will be highly employable in the wind energy industry. The detailed comments of the reviewers are included in the report.« less

  11. Cultural minority students' experiences with intercultural competency in medical education.

    PubMed

    Leyerzapf, Hannah; Abma, Tineke

    2017-05-01

    Medical schools increasingly value and focus on teaching students intercultural competency within present-day multicultural society. Little is known about the experiences of cultural minority students in intercultural competence activities. This article discusses the intercultural competence activities of medical education in a Dutch university from the perspective of cultural minority students. We will formulate recommendations for how to stimulate intercultural competency in, as well as inclusiveness of, medical education. A qualitative evaluation was performed within a medical school in the Netherlands. Data were collected through interviews (n = 23), a focus group (six participants) and participant observations (20 hours). Thematic analysis was performed. Cultural minority students experienced a lack of respect and understanding by cultural majority students and teachers. Education activities intended to transfer intercultural knowledge, address personal prejudice and stimulate intercultural sensitivity were perceived as stigmatising and as creating an unsafe climate for cultural minority students. Cultural minority and majority students on campus seemed segregated and the intercultural awareness of minority students was not integrated in intercultural competence activities. As cultural minority students were confronted with microaggressions, the medical school did not succeed in creating a safe education environment for all students. Contrary to their aims and intentions, intercultural competence activities had limited effect and seemed to support the polarisation of cultural minority and majority students and teachers. This can be seen as pointing towards a hidden curriculum privileging majority over minority students. For structural integration of intercultural competency in medical education, the focus must penetrate beyond curricular activities towards the critical addressing of the culture and structure of medical school. Collective commitment to creating a safe and inclusive education climate is vital. This requires fostering social cohesion between minority and majority students and teachers, raising awareness and the practice by all involved of critical (self-)reflexivity on cultural prejudice and dominant, exclusionary norms in academic medicine. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

  12. Structural Characterization of the Degradation Products of a Minor Natural Sweet Diterpene Glycoside Rebaudioside M under Acidic Conditions

    PubMed Central

    Prakash, Indra; Chaturvedula, Venkata Sai Prakash; Markosyan, Avetik

    2014-01-01

    Degradation of rebaudioside M, a minor sweet component of Stevia rebaudiana Bertoni, under conditions that simulated extreme pH and temperature conditions has been studied. Thus, rebaudioside M was treated with 0.1 M phosphoric acid solution (pH 2.0) and 80 °C temperature for 24 h. Experimental results indicated that rebaudioside M under low pH and higher temperature yielded three minor degradation compounds, whose structural characterization was performed on the basis of 1D (1H-, 13C-) & 2D (COSY, HSQC, HMBC) NMR, HRMS, MS/MS spectral data as well as enzymatic and acid hydrolysis studies. PMID:24424316

  13. Anti-LGBT and Anti-immigrant Structural Stigma: An Intersectional Analysis of Sexual Minority Men's HIV Risk When Migrating to or Within Europe.

    PubMed

    Pachankis, John E; Hatzenbuehler, Mark L; Berg, Rigmor C; Fernández-Dávila, Percy; Mirandola, Massimo; Marcus, Ulrich; Weatherburn, Peter; Schmidt, Axel J

    2017-12-01

    Gay, bisexual, and other men who have sex with men (MSM) might be particularly likely to migrate to experience freedoms unavailable in their home countries. Structural stigma (eg, laws and policies promoting the unequal treatment of oppressed populations) in MSM migrants' sending and receiving countries represent potential barriers to HIV prevention among this intersectional population. This study represents the first investigation of structural determinants of HIV risk in a large, geographically diverse sample of MSM migrants. The 2010 European MSM Internet Survey (n = 23,371 migrants) was administered across 38 European countries. Structural stigma was assessed using (1) national laws and policies promoting unequal treatment of sexual minorities across 181 countries worldwide and (2) national attitudes against immigrants in the 38 receiving countries. We also assessed linguistic status, time since migrating, and 5 HIV-prevention outcomes. Structural stigma toward sexual minorities (in sending and receiving countries) and toward immigrants (in receiving countries) was associated with a lack of HIV-prevention knowledge, service coverage, and precautionary behaviors among MSM migrants. Linguistic status and time since migrating moderated some associations between structural stigma and lack of HIV prevention. Structural stigma toward MSM and immigrants represents a modifiable structural determinant of the global HIV epidemic.

  14. Effects of substrate network topologies on competition dynamics

    NASA Astrophysics Data System (ADS)

    Lee, Sang Hoon; Jeong, Hawoong

    2006-08-01

    We study a competition dynamics, based on the minority game, endowed with various substrate network structures. We observe the effects of the network topologies by investigating the volatility of the system and the structure of follower networks. The topology of substrate structures significantly influences the system efficiency represented by the volatility and such substrate networks are shown to amplify the herding effect and cause inefficiency in most cases. The follower networks emerging from the leadership structure show a power-law incoming degree distribution. This study shows the emergence of scale-free structures of leadership in the minority game and the effects of the interaction among players on the networked version of the game.

  15. The application of minority stress theory to marijuana use among sexual minority adolescents.

    PubMed

    Goldbach, Jeremy T; Schrager, Sheree M; Dunlap, Shannon L; Holloway, Ian W

    2015-02-01

    Previous research indicates that lesbian, gay, and bisexual (LGB) adolescents are at increased risk for substance use, including heightened rates of marijuana use. Minority stress theory suggests that difficult social situations create a state of chronic stress that leads to poor health outcomes for LGB adults; however, the applicability of this model has not been well explored in relation to substance use among LGB adolescents. The current study is a secondary analysis of the OutProud survey, conducted in 2000. The original study used purposive sampling to collect data from 1,911 LGB adolescents (age 12-17) across the United States, and represents the largest known study to explore experiences specific to identifying as LGB, such as homophobia and gay-related victimization. We used structural equation modeling (SEM) to explore the feasibility of applying a minority stress framework to understand marijuana use in this population. The final structural model for marijuana use in the LGB adolescent sample displayed excellent fit and modest explanatory power for marijuana use. Two of the five factors, community connectedness and internalized homophobia, were significantly (p < .05) associated with marijuana use. Findings suggest that minority stress theory may be appropriately applied to marijuana use in this population; however, better measurement of minority stress concepts for LGB adolescents is needed.

  16. Corynebacterium diphtheriae employs specific minor pilins to target human pharyngeal epithelial cells

    PubMed Central

    Mandlik, Anjali; Swierczynski, Arlene; Das, Asis; Ton-That, Hung

    2010-01-01

    Summary Adherence to host tissues mediated by pili is pivotal in the establishment of infection by many bacterial pathogens. Corynebacterium diphtheriae assembles on its surface three distinct pilus structures. The function and the mechanism of how various pili mediate adherence, however, have remained poorly understood. Here we show that the SpaA-type pilus is sufficient for the specific adherence of corynebacteria to human pharyngeal epithelial cells. The deletion of the spaA gene, which encodes the major pilin forming the pilus shaft, abolishes pilus assembly but not adherence to pharyngeal cells. In contrast, adherence is greatly diminished when either minor pilin SpaB or SpaC is absent. Antibodies directed against either SpaB or SpaC block bacterial adherence. Consistent with a direct role of the minor pilins, latex beads coated with SpaB or SpaC protein bind specifically to pharyngeal cells. Therefore, tissue tropism of corynebacteria for pharyngeal cells is governed by specific minor pilins. Importantly, immunoelectron microscopy and immunofluorescence studies reveal clusters of minor pilins that are anchored to cell surface in the absence of a pilus shaft. Thus, the minor pilins may also be cell wall anchored in addition to their incorporation into pilus structures that could facilitate tight binding to host cells during bacterial infection. PMID:17376076

  17. Local structures around the substituted elements in mixed layered oxides

    PubMed Central

    Akama, Shota; Kobayashi, Wataru; Amaha, Kaoru; Niwa, Hideharu; Nitani, Hiroaki; Moritomo, Yutaka

    2017-01-01

    The chemical substitution of a transition metal (M) is an effective method to improve the functionality of a material, such as its electrochemical, magnetic, and dielectric properties. The substitution, however, causes local lattice distortion because the difference in the ionic radius (r) modifies the local interatomic distances. Here, we systematically investigated the local structures in the pure (x = 0.0) and mixed (x = 0.05 or 0.1) layered oxides, Na(M1−xM′x)O2 (M and M′ are the majority and minority transition metals, respectively), by means of extended X-ray absorption fine structure (EXAFS) analysis. We found that the local interatomic distance (dM-O) around the minority element approaches that around the majority element to reduces the local lattice distortion. We further found that the valence of the minority Mn changes so that its ionic radius approaches that of the majority M. PMID:28252008

  18. NMR and computational methods applied to the 3- dimensional structure determination of DNA and ligand-DNA complexes in solution

    NASA Astrophysics Data System (ADS)

    Smith, Jarrod Anson

    2D homonuclear 1H NMR methods and restrained molecular dynamics (rMD) calculations have been applied to determining the three-dimensional structures of DNA and minor groove-binding ligand-DNA complexes in solution. The structure of the DNA decamer sequence d(GCGTTAACGC)2 has been solved both with a distance-based rMD protocol and an NOE relaxation matrix backcalculation-based protocol in order to probe the relative merits of the different refinement methods. In addition, three minor groove binding ligand-DNA complexes have been examined. The solution structure of the oligosaccharide moiety of the antitumor DNA scission agent calicheamicin γ1I has been determined in complex with a decamer duplex containing its high affinity 5'-TCCT- 3' binding sequence. The structure of the complex reinforces the belief that the oligosaccharide moiety is responsible for the sequence selective minor-groove binding activity of the agent, and critical intermolecular contacts are revealed. The solution structures of both the (+) and (-) enantiomers of the minor groove binding DNA alkylating agent duocarmycin SA have been determined in covalent complex with the undecamer DNA duplex d(GACTAATTGTC).d(GAC AATTAGTC). The results support the proposal that the alkylation activity of the duocarmycin antitumor antibiotics is catalyzed by a binding-induced conformational change in the ligand which activates the cyclopropyl group for reaction with the DNA. Comparisons between the structures of the two enantiomers covalently bound to the same DNA sequence at the same 5'-AATTA-3 ' site have provided insight into the binding orientation and site selectivity, as well as the relative rates of reactivity of these two agents.

  19. Future goal setting, task motivation and learning of minority and non-minority students in Dutch schools.

    PubMed

    Andriessen, Iris; Phalet, Karen; Lens, Willy

    2006-12-01

    Cross-cultural research on minority school achievement yields mixed findings on the motivational impact of future goal setting for students from disadvantaged minority groups. Relevant and recent motivational research, integrating Future Time Perspective Theory with Self-Determination Theory, has not yet been validated among minority students. To replicate across cultures the known motivational benefits of perceived instrumentality and internal regulation by distant future goals; to clarify when and how the future motivates minority students' educational performance. Participants in this study were 279 minority students (100 of Turkish and 179 of Moroccan origin) and 229 native Dutch students in Dutch secondary schools. Participants rated the importance of future goals, their perceptions of instrumentality, their task motivation and learning strategies. Dependent measures and their functional relations with future goal setting were simultaneously validated across minority and non-minority students, using structural equation modelling in multiple groups. As expected, Positive Perceived Instrumentality for the future increases task motivation and (indirectly) adaptive learning of both minority and non-minority students. But especially internally regulating future goals are strongly related to more task motivation and indirectly to more adaptive learning strategies. Our findings throw new light on the role of future goal setting in minority school careers: distant future goals enhance minority and non-minority students' motivation and learning, if students perceive positive instrumentality and if their schoolwork is internally regulated by future goals.

  20. Ethnic group differences in police notification about intimate partner violence.

    PubMed

    Ackerman, Jeffrey; Love, Tony P

    2014-02-01

    We analyzed data from the National Crime Victimization Survey to test whether individuals from different ethnic groups differentially notify the police after incidents of partner violence. After finding that minority groups notified the police about intimate partner violence (IPV) events more than non-minorities, we found that socioeconomic status differences between minorities and non-minorities explained a statistically significant proportion of the reasons underlying the differences in notification. We suggest that the pattern of our results supports a structural perspective and has potential implications about the subjective and objective efficacy of police involvement in IPV.

  1. InAs1-xSbx Alloys with Native Llattice Parameters Grown on Compositionally Graded Buffers: Structural and Optical Properties

    DTIC Science & Technology

    2013-08-15

    InAsSb, compositionally graded buffer, MBE, infrared, minority carrier lifetime, reciprocal space mapping Ding Wang, Dmitry Donetsky, Youxi Lin, Gela...infrared, minority carrier lifetime; reciprocal space mapping . Introduction GaSb based Ill-Y materials are widely used in the development of mid... space mapping (RSM) at the symmetric (004) and asymmetric (335) Bragg reflections. Figure 3 presents a set of RSM measurements for a structure

  2. Structural colored gels for tunable soft photonic crystals.

    PubMed

    Harun-Ur-Rashid, Mohammad; Seki, Takahiro; Takeoka, Yukikazu

    2009-01-01

    A periodically ordered interconnecting porous structure can be embodied in chemical gels by using closest-packed colloidal crystals as templates. The interconnecting porosity not only provides a quick response but also endows the porous gels with structural color arising from coherent Bragg optical diffraction. The structural colors revealed by porous gels can be regulated by several techniques, and thus, it is feasible to obtain desirable, smart, soft materials. A well-known thermosensitive monomer, N-isopropylacrylamide (NIPA), and other minor monomers were used to fabricate various structural colored gels. The selection of minor monomers depended on the targeted properties. This review focuses on the synthesis of templates, structural colored porous gels, and the applications of structural colored gel as smart soft materials for tunable photonic crystals. (c) 2009 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.

  3. Text vectorization based on character recognition and character stroke modeling

    NASA Astrophysics Data System (ADS)

    Fan, Zhigang; Zhou, Bingfeng; Tse, Francis; Mu, Yadong; He, Tao

    2014-03-01

    In this paper, a text vectorization method is proposed using OCR (Optical Character Recognition) and character stroke modeling. This is based on the observation that for a particular character, its font glyphs may have different shapes, but often share same stroke structures. Like many other methods, the proposed algorithm contains two procedures, dominant point determination and data fitting. The first one partitions the outlines into segments and second one fits a curve to each segment. In the proposed method, the dominant points are classified as "major" (specifying stroke structures) and "minor" (specifying serif shapes). A set of rules (parameters) are determined offline specifying for each character the number of major and minor dominant points and for each dominant point the detection and fitting parameters (projection directions, boundary conditions and smoothness). For minor points, multiple sets of parameters could be used for different fonts. During operation, OCR is performed and the parameters associated with the recognized character are selected. Both major and minor dominant points are detected as a maximization process as specified by the parameter set. For minor points, an additional step could be performed to test the competing hypothesis and detect degenerated cases.

  4. Effects of proline cis-trans isomerization on TB domain secondary structure.

    PubMed Central

    Yuan, X.; Werner, J. M.; Knott, V.; Handford, P. A.; Campbell, I. D.; Downing, K.

    1998-01-01

    The transforming growth factor beta (TGF-beta) binding protein-like (TB) domain is found principally in proteins localized to extracellular matrix fibrils, including human fibrillin-1, the defective protein in the Marfan syndrome. Analysis of the nuclear magnetic resonance (NMR) data for the sixth TB module from human fibrillin-1 has revealed the existence of two stable conformers that differ in the isomerization states of two proline residues. Unusually, the two isoforms do not readily interconvert and are stable on the time scale of milliseconds. We have computed independent structures of the major and minor conformers of TB6 to assess how the domain fold adjusts to incorporate alternatively cis- or trans-prolines. Based on previous observations, it has been suggested that multiple conformers can only be accommodated in flexible regions of protein structure. In contrast, P22, which exists in trans in the major form and cis in the minor form of TB6, is in a rigid region of the domain, which is confirmed by backbone dynamics measurements. Overall, the structures of the major and minor conformers are similar. However, the secondary structure topologies of the two forms differ as a direct consequence of the changes in proline conformation. PMID:9792099

  5. Two distinct structures of alpha-conotoxin GI in aqueous solution.

    PubMed

    Maslennikov, I V; Sobol, A G; Gladky, K V; Lugovskoy, A A; Ostrovsky, A G; Tsetlin, V I; Ivanov, V T; Arseniev, A S

    1998-06-01

    The detailed analysis of conformational space of alpha-conotoxin GI in aqueous solution has been performed on the basis of two-dimensional NMR spectroscopy data using multiconformational approach. As the result, two topologically distinct interconvertible sets of GI conformations (populations of 78% and 22%) have been found. A common feature of the two sets is the Asn4-Cys7 beta-turn. The Gly8 to Tyrll region has a structure of right-handed helical turn in the major set and two sequential bends in the minor one. N-terminus and C-terminus also have different orientations, anti-parallel in the major conformational set and parallel in the minor one. An average pairwise rmsd for backbone heavy atoms is 0.56 A in the major set, 0.23 A in the minor, and 1.85 A between the structures of the two sets. The X-ray structure of GI [Guddat, L. W., Martin, J. A., Shan, L., Edmundson, A. B. & Gray, W. R. (1996) Biochemistry 35, 11329 - 11335] has the same folding pattern as the major NMR set, the average backbone rmsd between the two structures being 0.77 A.

  6. Morphological evidence for a past minor merger in the Seyfert galaxy NGC 1068†

    NASA Astrophysics Data System (ADS)

    Tanaka, Ichi; Yagi, Masafumi; Taniguchi, Yoshiaki

    2017-12-01

    Deep optical imaging with both Hyper Suprime-Cam and Suprime-Cam on the 8.2 m Subaru Telescope reveals a number of outer faint structures around the archetypical Seyfert galaxy NGC 1068 (M 77). We find three ultra diffuse objects (UDOs) around NGC 1068. Since these UDOs are located within the projected distance of 45 kpc from the center of NGC 1068, they appear to be associated with NGC 1068. Hereafter, we call them UDO-SW, UDO-NE, and UDO-SE where UDO = Ultra Diffuse Object, SW = southwest, NE = northwest, and SE = southeast; note that UDO-SE was already found in the SDSS Stripe 82 data. Among them, UDO-NE and UDO-SW appear to be a part of a loop or stream structure around the main body of NGC 1068, providing evidence for the physical connection to NGC 1068. We consider that UDO-SE may be a tidal dwarf galaxy. We also find another UDO-like object that is two magnitudes fainter and smaller by a factor of 3 to 5 than those of the three UDOs. This object may belong to a class of low surface brightness galaxy. Since this object is located along the line connecting UDO-NE and UDO-SW, it is suggested that this object is related to the past interaction event that formed the loop by UDO-NE and UDO-SW, thus implying the physical connection to NGC 1068. Another newly discovered feature is an asymmetric outer one-arm structure emanating from the western edge of the outermost disk of NGC 1068 together with a ripple-like structure at the opposite side. These structures are expected to arise in a late phase of a minor merger, according to published numerical simulations of minor mergers. All these lines of evidence show that NGC 1068 experienced a minor merger several billion years ago. We then discuss the minor-merger driven triggering of nuclear activity in the case of NGC 1068.

  7. A Relational Model of Sexual Minority Mental and Physical Health: The Negative Effects of Shame on Relationships, Loneliness, and Health

    PubMed Central

    Mereish, Ethan H.; Poteat, V. Paul

    2015-01-01

    Sexual minorities (e.g., lesbians, gay men, bisexual individuals) are at higher risk for mental and physical health disparities than heterosexuals, and some of these disparities relate to minority stressors such as discrimination. Yet, there is little research elucidating pathways that predict health or that promote resiliency among sexual minorities. Building on the minority stress model, the present study utilized relational cultural theory to situate sexual minority health within a relational framework. Specifically, the study tested mediators of the relationships between distal (i.e., discrimination, rejection, victimization) and proximal stressors (i.e., internalized homophobia, sexual orientation concealment) and psychological and physical distress for sexual minorities. Among 719 sexual minority adults, structural equation modeling analyses were used to test four models reflecting the mediating effects of shame, poorer relationships with a close peer and the LGBT community, and loneliness on the associations between minority stressors and psychological distress (i.e., depression and anxiety) and physical distress (i.e., distressing physical symptoms). As hypothesized, the associations between distal and proximal minority stressors and distress were mediated by shame, poorer relationships with a close peer and the LGBT community, and loneliness. Findings underscore the possible relational and interpersonal mechanisms by which sexual minority stressors lead to psychological and physical distress. PMID:26010289

  8. Properties of interaction networks underlying the minority game.

    PubMed

    Caridi, Inés

    2014-11-01

    The minority game is a well-known agent-based model with no explicit interaction among its agents. However, it is known that they interact through the global magnitudes of the model and through their strategies. In this work we have attempted to formalize the implicit interactions among minority game agents as if they were links on a complex network. We have defined the link between two agents by quantifying the similarity between them. This link definition is based on the information of the instance of the game (the set of strategies assigned to each agent at the beginning) without any dynamic information on the game and brings about a static, unweighed and undirected network. We have analyzed the structure of the resulting network for different parameters, such as the number of agents (N) and the agent's capacity to process information (m), always taking into account games with two strategies per agent. In the region of crowd effects of the model, the resulting networks structure is a small-world network, whereas in the region where the behavior of the minority game is the same as in a game of random decisions, networks become a random network of Erdos-Renyi. The transition between these two types of networks is slow, without any peculiar feature of the network in the region of the coordination among agents. Finally, we have studied the resulting static networks for the full strategy minority game model, a maximal instance of the minority game in which all possible agents take part in the game. We have explicitly calculated the degree distribution of the full strategy minority game network and, on the basis of this analytical result, we have estimated the degree distribution of the minority game network, which is in accordance with computational results.

  9. Minor pyrano-isoflavones from Eriosema kraussianum: activity-, structure-, and chemical reaction studies.

    PubMed

    Drewes, Siegfried E; Horn, Marion M; Khan, Fatima; Munro, Orde Q; Dhlamini, Jabu T B; Rakuambo, Christopher; Meyer, J J Marion

    2004-07-01

    The isolation and identification of two minor pyrano-isoflavones from Eriosema kraussianum is described. New studies on the original pyrano-isoflavones shows that: (i) kraussianone 2 (a major compound in the plant) can be cyclised under acid conditions, (ii) kraussianones 3 and 5 cause contraction (not relaxation as anticipated) of corpus cavernosum tissue and (iii) the structures proposed previously for 4 and 5 are confirmed by the data obtained from an X-ray study of 5.

  10. The structure of a β-(1→6)-d-glucan from yeast cell walls

    PubMed Central

    Manners, David J.; Masson, Alan J.; Patterson, James C.; Björndal, Håkan; Lindberg, Bengt

    1973-01-01

    By selective enzymolysis, or chemical fractionation, a minor polysaccharide component has been isolated from yeast (Saccharomyces cerevisiae) glucan. This minor component has a degree of polymerization of about 130–140, a highly branched structure, and a high proportion of β-(1→6)-glucosidic linkages. The molecules also contain a smaller proportion of β-(1→3)-glucosidic linkages that serve mainly as interchain linkages, but some may also be inter-residue linkages. PMID:4590991

  11. A new anti-MRSA antibiotic complex, WAP-8294A II. Structure characterization of minor components by ESI LCMS and MS/MS.

    PubMed

    Kato, Azusa; Hirata, Haruhisa; Ohashi, Yoshitami; Fujii, Kiyonaga; Mori, Kenji; Harada, Ken-ichi

    2011-05-01

    The anti-MRSA antibiotic, WAP-8294A, was isolated from the fermentation broth of Lysobacter sp. The major component, WAP-8294A2, is composed of 1 mol of Gly, L-Leu, L-Glu, D-Asn, D-Trp, D-threo-β-hydroxyasparagine, N-Me-D-Phe and N-Me-L-Val, and 2 mol of L-Ser, D-Orn and D-3-hydroxy-7-Me-octanoic acid. The structure of the WAP-8294A2 was mainly determined as a cyclic depsipeptide by 2D NMR experiments. However, it was difficult to use the NMR experiment to determine the minor components, A1, A4 and Ax13, isolated in small amounts. In the present study, ESI MS/MS was applied to the structure elucidation of these minor components. The structures of these minor components were determined on the basis of the fragmentation pattern of the product ions of WAP-8294A2 in the ESI MS/MS. As a result, it was confirmed that A1 and A4 had the same amino acid sequence as A2, while A1 and A4 had the 3-OH-octanoic acid and 3-OH-8-Me-nonanoic acid, respectively, in the place of the 3-OH-7-Me-octanoic acid in A2. In the structure of Ax13, it was found that Gly of A2 was changed to β-Ala of Ax13. © 2011 Japan Antibiotics Research Association All rights reserved

  12. Minority Stress and Intimate Partner Violence Among Gay and Bisexual Men in Atlanta.

    PubMed

    Stephenson, Rob; Finneran, Catherine

    2017-07-01

    Intimate partner violence (IPV) rates are disproportionately high among sexual minority populations. Few studies have examined the plausible relationship between minority stress and IPV among men who have sex with men. This study examines the associations between IPV and three indicators of minority stress: internalized homophobia, sexuality-based discrimination, and racism, in a large venue-based sample of gay and bisexual men from Atlanta, USA. Each of the minority stress measures was found to be significantly associated with increased odds of self-reporting any form of receipt of IPV. Significant associations were also identified between perpetration of IPV and minority stressors, with most types of IPV perpetration linked to internalized homophobia. This study confirms findings in a growing body of research supporting the relationship between minority stress and increased prevalence of IPV among men who have sex with men, and points to the need to address structural factors in IPV prevention programs for male-male couples.

  13. Minority Stress and Intimate Partner Violence Among Gay and Bisexual Men in Atlanta

    PubMed Central

    Stephenson, Rob; Finneran, Catherine

    2016-01-01

    Intimate partner violence (IPV) rates are disproportionately high among sexual minority populations. Few studies have examined the plausible relationship between minority stress and IPV among men who have sex with men. This study examines the associations between IPV and three indicators of minority stress: internalized homophobia, sexuality-based discrimination, and racism, in a large venue-based sample of gay and bisexual men from Atlanta, USA. Each of the minority stress measures was found to be significantly associated with increased odds of self-reporting any form of receipt of IPV. Significant associations were also identified between perpetration of IPV and minority stressors, with most types of IPV perpetration linked to internalized homophobia. This study confirms findings in a growing body of research supporting the relationship between minority stress and increased prevalence of IPV among men who have sex with men, and points to the need to address structural factors in IPV prevention programs for male–male couples. PMID:27821702

  14. Antecedents of intra/intergroup friendships and stress levels among ethnic and religious minority members.

    PubMed

    Zagefka, Hanna; Mohamed, Abdinasir; Mursi, Gehad; Lay, Siugmin

    2016-12-01

    Two studies tested a model, whereby, identification with the minority group was predicted to impact on acculturation preferences, which in turn were proposed to impact involvement in intragroup friendships with other minority members, intergroup friendships with majority members and stress experienced by minority members. A direct path from minority identification to stress was also included in the model. The model was tested using structural equation modelling on survey data collected from Muslim women (N = 250) and from Somali minority members (N = 198) in Britain. Results supported predictions and revealed that identification was associated with more culture maintenance preference and less culture adoption preference. Culture maintenance preference was associated with involvement in intragroup friendships, and culture adoption preference was associated with involvement in intergroup friendships and increased stress. Practical applications of the findings are discussed. © 2015 International Union of Psychological Science.

  15. Value of the small cohort study including a physical examination for minor structural defects in identifying new human teratogens.

    PubMed

    Chambers, Christina D

    2011-03-01

    Most known human teratogens are associated with a unique or characteristic pattern of major and minor malformations and this pattern helps to establish the causal link between the teratogenic exposure and the outcome. Although traditional case-control and cohort study designs can help identify potential teratogens, there is an important role for small cohort studies that include a dysmorphological examination of exposed and unexposed infants for minor structural defects. In combination with other study design approaches, the small cohort study with a specialized physical examination fulfills a necessary function in screening for new potential teratogens and can help to better delineate the spectrum and magnitude of risk for known teratogens. © 2011 The Author. Congenital Anomalies © 2011 Japanese Teratology Society.

  16. Teaching minority children hygiene: investigating hygiene education in kindergartens and homes of ethnic minority children in northern Vietnam.

    PubMed

    Rheinländer, Thilde; Samuelsen, Helle; Dalsgaard, Anders; Konradsen, Flemming

    2015-01-01

    Ethnic minority children in Vietnam experience high levels of hygiene- and sanitation-related diseases. Improving hygiene for minority children is therefore vital for improving child health. The study objective was to investigate how kindergarten and home environments influence the learning of hygiene of pre-school ethnic minority children in rural Vietnam. Eight months of ethnographic field studies were conducted among four ethnic minority groups living in highland and lowland communities in northern Vietnam. Data included participant observation in four kindergartens and 20 homes of pre-school children, together with 67 semi-structured interviews with caregivers and five kindergarten staff. Thematic analysis was applied and concepts of social learning provided inputs to the analysis. This study showed that poor living conditions with lack of basic sanitation infrastructures were important barriers for the implementation of safe home child hygiene. Furthermore, the everyday life of highland villages, with parents working away from the households resulted in little daily adult supervision of safe child hygiene practices. While kindergartens were identified as potentially important institutions for improving child hygiene education, essential and well-functioning hygiene infrastructures were lacking. Also, hygiene teaching relied on theoretical and non-practice-based learning styles, which did not facilitate hygiene behaviour change in small children. Minority children were further disadvantaged as teaching was only provided in non-minority language. Kindergartens can be important institutions for the promotion of safe hygiene practices among children, but they must invest in the maintenance of hygiene and sanitation infrastructures and adopt a strong practice-based teaching approach in daily work and in teacher's education. To support highland minority children in particular, teaching styles must take local living conditions and caregiver structures into account and teach in local languages. Creating stronger links between home and institutional learning environments can be vital to support disadvantaged highland families in improving child health.

  17. The Influence of Interactions and Minor Mergers on the Structure of Galactic Disks

    NASA Astrophysics Data System (ADS)

    Schwarzkopf, U.

    1999-07-01

    A detailed statistical study is presented focused on the effects of minor mergers and tidal interactions on the radial and vertical structure of galactic disks. The fundamental disk parameters of 112 highly-inclined/edge-on galaxies are studied in optical and in near-infrared passbands. This sample consists of two subsamples of 65 non-interacting and 47 interacting/merging galaxies. Additionally, 41 of these galaxies were observed in the near-infrared. A 3-dimensional disk modelling and -fitting procedure was applied in order to analyze and to compare characteristic disk parameters of all sample galaxies. Furthermore, n-body simulations were performed in order to study the influence of minor mergers in the mass range Msat/Mdisk 0.1 on the vertical structure of disks in spiral galaxies. In particular, the dependence of vertical, tidally-triggered disk thickening on initial disk parameters is investigated. The quantitative results of both simulation and observation are compared in order to find similarities in the distribution of characteristic disk parameters.

  18. Minor Structural Change to Tertiary Sulfonamide RORc Ligands Led to Opposite Mechanisms of Action

    PubMed Central

    2014-01-01

    A minor structural change to tertiary sulfonamide RORc ligands led to distinct mechanisms of action. Co-crystal structures of two compounds revealed mechanistically consistent protein conformational changes. Optimized phenylsulfonamides were identified as RORc agonists while benzylsulfonamides exhibited potent inverse agonist activity. Compounds behaving as agonists in our biochemical assay also gave rise to an increased production of IL-17 in human PBMCs whereas inverse agonists led to significant suppression of IL-17 under the same assay conditions. The most potent inverse agonist compound showed >180-fold selectivity over the ROR isoforms as well as all other nuclear receptors that were profiled. PMID:25815138

  19. Academic and Career Expectations of Ethnic Minority Youth in Hong Kong

    ERIC Educational Resources Information Center

    Cheung, Francis; Lai, Beatrice P. Y.; Wu, Anise M. S.; Ku, Lisbeth

    2015-01-01

    Based on social-cognitive career theory (SCCT), we explore how ethnic identity, parental occupation, efficacy in learning Chinese, and learning experience relate to ethnic minority adolescents' academic and career expectations. The participants are 632 Southeast Asian adolescents in Hong Kong. In accordance with SCCT, structural equation modeling…

  20. Values Affirmation Intervention Reduces Achievement Gap between Underrepresented Minority and White Students in Introductory Biology Classes

    ERIC Educational Resources Information Center

    Jordt, Hannah; Eddy, Sarah L.; Brazil, Riley; Lau, Ignatius; Mann, Chelsea; Brownell, Sara E.; King, Katherine; Freeman, Scott

    2017-01-01

    Achievement gaps between underrepresented minority (URM) students and their white peers in college science, technology, engineering, and mathematics classrooms are persistent across many white-majority institutions of higher education. Attempts to reduce this phenomenon of underperformance through increasing classroom structure via active learning…

  1. Testimony Before the Subcommittee on General Oversight and Minority Enterprise, Committee on Small Business,

    DTIC Science & Technology

    1980-03-01

    Subcommittee on General Oversight and Minority Enterprise, Committee on Small Business March 3, 1980 -- I ’zm golng:to providesa structural overview of the key...Industry Newspaper firms are small businesses . To illustrate, the median circulation for the 1580 daily newspapers publishing in 1977 was 12,000. During...UNCLASSIFIEO RAN/P-6502 NL " ’~~~- Iililii111118 iTESTIMONY BEFORE THE SUBCOMMITTEE ON GENERAL.OVERSIGHT AND MINORITY ENTERPRISE, COMMITTEE ON SMALL BWTSINESS

  2. Buffalo Metropolitan Area, New York Water Resources Management. Interim Report on Feasibility of Flood Management in Cazenovia Creek Watershed.

    DTIC Science & Technology

    1977-03-01

    flow downstream causing minor ice Jamming in Reaches 1 and 2, these reaches may derive less direct benefit from the proposed structural works than...their greatest overall impact upon the lower and central basins. The upper basin experiences relatively minor flood damages and would be little affected...dipping to the south at approximately 40 feet per mile. This is locally affected by minor folding which may modify the dip to as much as 60 feet per

  3. Sediment-Water Nitrogen Fluxes in a Backwater System of the Upper Mississippi River

    DTIC Science & Technology

    2008-01-01

    2002. Nitrogen uptake by the floating macrophyte Lemna minor . New Phytologist 155, 285-292. Chan, Y. K., and N. E. R. Campbell. 1978. Phytoplankton...nitrite-N in the water col- umn were usually minor at both stations. Ammonium-N concentrations accounted for a minor portion of the total N in the...rudimentary root structure such as Ceratophyllum (which is a dominant 19 ERDC TN-SWWRP-08-01 January 2008 species in Third Lake) and Lemna sp. rely on

  4. The role of porcine reproductive and respiratory syndrome (PRRS) virus structural and non-structural proteins in virus pathogenesis.

    PubMed

    Music, Nedzad; Gagnon, Carl A

    2010-12-01

    Porcine reproductive and respiratory syndrome (PRRS) is an economically devastating viral disease affecting the swine industry worldwide. The etiological agent, PRRS virus (PRRSV), possesses a RNA viral genome with nine open reading frames (ORFs). The ORF1a and ORF1b replicase-associated genes encode the polyproteins pp1a and pp1ab, respectively. The pp1a is processed in nine non-structural proteins (nsps): nsp1α, nsp1β, and nsp2 to nsp8. Proteolytic cleavage of pp1ab generates products nsp9 to nsp12. The proteolytic pp1a cleavage products process and cleave pp1a and pp1ab into nsp products. The nsp9 to nsp12 are involved in virus genome transcription and replication. The 3' end of the viral genome encodes four minor and three major structural proteins. The GP(2a), GP₃ and GP₄ (encoded by ORF2a, 3 and 4), are glycosylated membrane associated minor structural proteins. The fourth minor structural protein, the E protein (encoded by ORF2b), is an unglycosylated membrane associated protein. The viral envelope contains two major structural proteins: a glycosylated major envelope protein GP₅ (encoded by ORF5) and an unglycosylated membrane M protein (encoded by ORF6). The third major structural protein is the nucleocapsid N protein (encoded by ORF7). All PRRSV non-structural and structural proteins are essential for virus replication, and PRRSV infectivity is relatively intolerant to subtle changes within the structural proteins. PRRSV virulence is multigenic and resides in both the non-structural and structural viral proteins. This review discusses the molecular characteristics, biological and immunological functions of the PRRSV structural and nsps and their involvement in the virus pathogenesis.

  5. Studies in electron phenomena in MOS structures: The pulsed C-V method. M.S. Thesis. Abstract Only

    NASA Technical Reports Server (NTRS)

    Kaplan, G.

    1983-01-01

    The pulse hysteresis capacitance voltage (C-V) provides a straight forward technique for measuring the change of various charges in MOS structures and a tool for investigating the kinetics of various electron phenomena is developed and described. The method can be used for measuring the energy distribution and kinetics of surface states with the resolution of about 1/5 x 10 to the -9 power cm eV. Some transients in an MOS structure, particularly, the thermal generation of minority charge carriers via surface states and the relaxation of minority charge carriers supplied from the inversion layer outside the MOS structure are theoretically investigated. Analytical expressions which clearly present the physics of those electron phenomena are derived.

  6. Effect of Minor Alloying Elements on Localized Corrosion Behavior of Aluminum-Copper-Magnesium based Solid Solution Alloys

    NASA Astrophysics Data System (ADS)

    Aburada, Tomohiro

    2011-12-01

    The effects and mechanistic roles of a minor alloying element, Ni, on the localized corrosion behavior were explored by studying (Al75Cu 17Mg8)97Ni3 and Al70Cu 18Mg12 amorphous alloys. To explore the minor alloying element limited to the outer surface layers, the corrosion behavior of Al70Cu 18Mg12 amorphous alloy in solutions with and without Ni 2+ was also studied. Both Ni alloying and Ni2+ in solution improved the localized corrosion resistance of the alloys by ennobling the pitting and repassivation potentials. Pit growth by the selective dissolution of Al and Mg was also suppressed by Ni alloying. Remaining Cu and Ni reorganized into a Cu-rich polycrystalline nanoporous structure with continuous ligaments in pits. The minor Ni alloying and Ni2+ in solution suppressed the coarsening of the ligaments in the dealloyed nanoporous structure. The presence of relatively immobile Ni atoms at the surface suppressed the surface diffusion of Cu, which reduced the coarsening of the nanoporous structure, resulting in the formation of 10 to 30 nm wide Cu ligaments. Two mechanistic roles of minor alloying elements in the improvement of the pitting corrosion resistance of the solid solution alloys are elucidated. The first role is the suppression of active dissolution by altering the atomic structure. Ni in solid solution formed stronger bonds with Al, and reduces the probability of weaker Al-Al bonds. The second role is to hinder dissolution by producing a greater negative shift of the true interfacial potential at the dissolution front under the dealloyed layer due to the greater Ohmic resistance through the finer porous structure. These effects contributed to the elevation of pitting potentials by ennobling the applied potential required to produce enough dissolution for the stabilization of pits. Scientifically, this thesis advances the state of understanding of alloy dissolution, particularly the role of minor alloying elements on preferential oxidation at the atomic, nanometer, and micrometer scales. Technological implementations of the findings of the research are also discussed, including a new route to synthesize nanoporous materials with tunable porosity and new corrosion mitigation strategies for commercial Al-based alloys containing the detrimental Al2CuMg phase.

  7. A relational model of sexual minority mental and physical health: The negative effects of shame on relationships, loneliness, and health.

    PubMed

    Mereish, Ethan H; Poteat, V Paul

    2015-07-01

    Sexual minorities (e.g., lesbians, gay men, bisexual individuals) are at an increased risk for poorer mental and physical health outcomes than heterosexuals, and some of these health disparities relate to minority stressors such as discrimination. Yet, there is little research elucidating pathways that predict health or that promote resiliency among sexual minorities. Building on the minority stress model, the present study utilized relational cultural theory to situate sexual minority health within a relational framework. Specifically, the study tested mediators of the relationships between distal (i.e., discrimination, rejection, victimization) and proximal stressors (i.e., internalized homophobia, sexual orientation concealment) and psychological and physical distress for sexual minorities. Among 719 sexual minority adults, structural equation modeling analyses were used to test 4 models reflecting the mediating effects of shame, poorer relationships with a close peer and the lesbian/gay/bisexual/transgender (LGBT) community, and loneliness on the associations between minority stressors and psychological distress (i.e., depression and anxiety) and physical distress (i.e., distressing physical symptoms). As hypothesized, the associations between distal and proximal minority stressors and distress were mediated by shame, poorer relationships with a close peer and the LGBT community, and loneliness. Findings underscore the possible relational and interpersonal mechanisms by which sexual minority stressors lead to psychological and physical distress. (c) 2015 APA, all rights reserved).

  8. The Geography of Sexual Orientation: Structural Stigma and Sexual Attraction, Behavior, and Identity Among Men Who Have Sex with Men Across 38 European Countries.

    PubMed

    Pachankis, John E; Hatzenbuehler, Mark L; Mirandola, Massimo; Weatherburn, Peter; Berg, Rigmor C; Marcus, Ulrich; Schmidt, Axel J

    2017-07-01

    While the prevalence of sexual identities and behaviors of men who have sex with men (MSM) varies across countries, no study has examined country-level structural stigma toward sexual minorities as a correlate of this variation. Drawing on emerging support for the context-dependent nature of MSM's open sexual self-identification cross-nationally, we examined country-level structural stigma as a key correlate of the geographic variation in MSM's sexual attraction, behavior, and identity, and concordance across these factors. Data come from the European MSM Internet Survey, a multi-national dataset containing a multi-component assessment of sexual orientation administered across 38 European countries (N = 174,209). Country-level stigma was assessed using a combination of national laws and policies affecting sexual minorities and a measure of attitudes toward sexual minorities held by the citizens of each country. Results demonstrate that in more stigmatizing countries, MSM were significantly more likely to report bisexual/heterosexual attractions, behaviors, and identities, and significantly less likely to report concordance across these factors, than in less stigmatizing countries. Settlement size moderated associations between country-level structural stigma and odds of bisexual/heterosexual attraction and behavior, such that MSM living in sparsely populated locales within high-structural stigma countries were the most likely to report bisexual or heterosexual behaviors and attractions. While previous research has demonstrated associations between structural stigma and adverse physical and mental health outcomes among sexual minorities, this study was the first to show that structural stigma was also a key correlate not only of sexual orientation identification, but also of MSM's sexual behavior and even attraction. Findings have implications for understanding the ontology of MSM's sexuality and suggest that a comprehensive picture of MSM's sexuality will come from attending to the local contexts surrounding this important segment of the global population.

  9. Origin of flatband voltage shift and unusual minority carrier generation in thermally grown GeO2/Ge metal-oxide-semiconductor devices

    NASA Astrophysics Data System (ADS)

    Hosoi, Takuji; Kutsuki, Katsuhiro; Okamoto, Gaku; Saito, Marina; Shimura, Takayoshi; Watanabe, Heiji

    2009-05-01

    Improvement in electrical properties of thermally grown GeO2/Ge metal-oxide-semiconductor (MOS) capacitors, such as significantly reduced flatband voltage (VFB) shift, small hysteresis, and minimized minority carrier response in capacitance-voltage (C-V) characteristics, has been demonstrated by in situ low temperature vacuum annealing prior to gate electrode deposition. Thermal desorption analysis has revealed that not only water but also hydrocarbons are easily infiltrated into GeO2 layers during air exposure and desorbed at around 300 °C, indicating that organic molecules within GeO2/Ge MOS structures are possible origins of electrical defects. The inversion capacitance, indicative of minority carrier generation, increases with air exposure time for Au/GeO2/Ge MOS capacitors, while maintaining an interface state density (Dit) of about a few 1011 cm-2 eV-1. Unusual increase in inversion capacitance was found to be suppressed by Al2O3 capping (Au/Al2O3/GeO2/Ge structures). This suggests that electrical defects induced outside the Au electrode by infiltrated molecules may enhance the minority carrier generation, and thus acting as a minority carrier source just like MOS field-effect transistors.

  10. Bisexual-Specific Minority Stressors, Psychological Distress, and Suicidality in Bisexual Individuals: the Mediating Role of Loneliness.

    PubMed

    Mereish, Ethan H; Katz-Wise, Sabra L; Woulfe, Julie

    2017-08-01

    Bisexual individuals are at higher risk for poor mental health outcomes compared to heterosexual as well as lesbian and gay individuals and experience minority stressors, such as discrimination, from both heterosexual and sexual minority communities. However, there is little research examining the negative effects of bisexual-specific minority stressors on bisexual individuals' mental health as well as psychological factors that might help explain minority stressors' deleterious effects. This research examined the effects of distal minority stressors (i.e., anti-bisexual experiences from both heterosexual as well as lesbian and gay people) and proximal stressors (i.e., internalized heterosexism and sexual orientation concealment) on psychological distress and suicidality among bisexual adults (N = 503). Building on the relational framing of the minority stress model, we also tested one relational factor (i.e., loneliness) as a mediator of the associations between distal and proximal minority stressors and poor mental health (i.e., psychological distress and suicidality). Structural equation modeling analyses were used to test the mediating effects of loneliness on the associations between minority stressors and psychological distress and suicidality. Although distal and proximal minority stressors were not associated with each other, loneliness mediated the effects of distal and proximal minority stressors on psychological distress and suicidality. The results of this study underscore the importance of targeting bisexual-specific minority stressors as well as loneliness in preventive interventions to improve the mental health of bisexual individuals.

  11. Improving Urban Minority Girls' Health Via Community Summer Programming.

    PubMed

    Bohnert, Amy M; Bates, Carolyn R; Heard, Amy M; Burdette, Kimberly A; Ward, Amanda K; Silton, Rebecca L; Dugas, Lara R

    2017-12-01

    Summertime has emerged as a high-risk period for weight gain among low-income minority youth who often experience a lack of resources when not attending school. Structured programming may be an effective means of reducing risk for obesity by improving obesogenic behaviors among these youth. The current multi-method study examined sedentary time, physical activity, and dietary intake among low-income urban minority girls in two contexts: an unstructured summertime setting and in the context of a structured 4-week community-based summer day camp program promoting physical activity. Data were analyzed using paired-sample t tests and repeated-measure analyses of variance with significance at the p < .05 level. Results evidenced no significant differences in total calories and fat consumed between the unstructured and structured settings. Participants exhibited significant increases in fruit consumption and physical activity and significant decreases in sedentary time of over 2 h/day and dairy consumption when engaged in structured summer programming. All improvements were independent of weight status and age, and African-American participants evidenced greater changes in physical activity during programming. The study concludes that structured, community-based summertime programming may be associated with fewer obesogenic behaviors in low-income urban youth and may be a powerful tool to address disparities in weight gain and obesity among high-risk samples.

  12. STRUCTURAL RACISM AND HEALTH INEQUITIES

    PubMed Central

    Gee, Gilbert C.; Ford, Chandra L.

    2014-01-01

    Racial minorities bear a disproportionate burden of morbidity and mortality. These inequities might be explained by racism, given the fact that racism has restricted the lives of racial minorities and immigrants throughout history. Recent studies have documented that individuals who report experiencing racism have greater rates of illnesses. While this body of research has been invaluable in advancing knowledge on health inequities, it still locates the experiences of racism at the individual level. Yet, the health of social groups is likely most strongly affected by structural, rather than individual, phenomena. The structural forms of racism and their relationship to health inequities remain under-studied. This article reviews several ways of conceptualizing structural racism, with a focus on social segregation, immigration policy, and intergenerational effects. Studies of disparities should more seriously consider the multiple dimensions of structural racism as fundamental causes of health disparities. PMID:25632292

  13. The Unique Leadership Needs of Minority Student Populations: Crafting a Leadership Identity

    ERIC Educational Resources Information Center

    Baughman, Kristen N.; Bruce, Jacklyn

    2011-01-01

    The purpose of this qualitative study was to determine how college-level minority student leaders make meaning of those leadership experiences. Semi-structured interviews were conducted with 12 students. Major findings noted a strong personal motivation to participate in student leadership positions. Further research on the impact of familial…

  14. Double-Play: Using Minor League Baseball to Apply Themes and Standards in Human Geography Courses

    ERIC Educational Resources Information Center

    Zeitler, Ezra

    2013-01-01

    Growing student interest in sports provides geography teachers with a special opportunity to make connections between it and fundamental concepts in the discipline. This article examines the structure, arrangement, relationships, and distinctions among minor league baseball franchise locations, stadia, and team names, and presents examples of…

  15. Factors influencing health care access perceptions and care-seeking behaviors of immigrant Latino sexual minority men and transgender individuals: Baseline findings from the HOLA intervention study

    PubMed Central

    Tanner, AE; Reboussin, BA; Mann, L; Ma, A; Song, E; Alonzo, J; Rhodes, SD

    2014-01-01

    Little is known about immigrant Latino sexual minorities' health seeking behaviors. This study examined factors associated with perceptions of access and actual care behaviors among this population in North Carolina. Methods A community-based participatory research partnership recruited 180 Latino sexual minority men and transgender individuals within preexisting social networks to participate in a sexual health intervention. Mixed-effects logistic regression models examined factors influencing health care access perceptions and use of services (HIV testing and routine check-ups). Results Results indicate that perceptions of access and actual care behaviors are low and affected by individual and structural factors, including: years living in NC, reported poor general health, perceptions of discrimination, micro-, meso-, and macro-level barriers, and residence in a Medically Underserved Area. Discussion To improve Latino sexual minority health, focus must be placed on multiple levels, individual characteristics (e.g., demographics), clinic factors (e.g., provider competence and clinic environment), and structural factors (e.g., discrimination). PMID:25418235

  16. The role of personality in predicting drug and alcohol use among sexual minorities.

    PubMed

    Livingston, Nicholas A; Oost, Kathryn M; Heck, Nicholas C; Cochran, Bryan N

    2015-06-01

    Research consistently demonstrates that sexual minority status is associated with increased risk of problematic substance use. Existing literature in this area has focused on group-specific minority stress factors (e.g., victimization and internalized heterosexism). However, no known research has tested the incremental validity of personality traits as predictors of substance use beyond identified group-specific risk factors. A sample of 704 sexual minority adults was recruited nationally from lesbian, gay, bisexual, transgender, queer, and questioning community organizations and social networking Web sites and asked to complete an online survey containing measures of personality, sexual minority stress, and substance use. Hierarchical regression models were constructed to test the incremental predictive validity of five-factor model personality traits over and above known sexual minority risk factors. Consistent with hypotheses, extraversion and conscientiousness were associated with drug and alcohol use after accounting for minority stress factors, and all factors except agreeableness were associated with substance use at the bivariate level of analysis. Future research should seek to better understand the role of normal personality structures and processes conferring risk for substance use among sexual minorities. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  17. Psychiatrists' views of compulsory psychiatric care of minors.

    PubMed

    Turunen, Suvi; Välimäki, Maritta; Kaltiala-Heino, Riittakerttu

    2010-01-01

    Commitment to psychiatric care is in Finland allowed for minors in broader terms than for adults. Minors can be committed to and detained in involuntary psychiatric treatment if they suffer from severe mental disorder and fulfil the additional commitment criteria defined in the Mental Health Act. Adults can be committed to involuntary psychiatric care only if they are mentally ill (=psychotic), and fulfil the additional criteria. Involuntary treatment of minors has been increasing steadily since the Mental Health Act was passed in 1991. This study was set up to find out whether the Finnish child and adolescent psychiatrists agree with the need for defining broader commitment criteria for minors, and why. Semi-structured, reflexive dyadic interviews were carried out with 44 psychiatrists working with children and adolescents. The data was analysed using qualitative and quantitative content analysis. The analysis showed that broader commitment criteria for minors were favoured referring to developmental needs related to childhood and adolescence, prevention of mental illnesses and inadequacy of descriptive diagnosis in childhood and adolescence. The commitment criteria were rather seen as too narrow for adults than as too broad for minors, and the medical rights of minors were preferred over self-determination. Copyright 2009 Elsevier Ltd. All rights reserved.

  18. Ethnic Minorities' Impression Management in the Interview: Helping or Hindering?

    PubMed

    Derous, Eva

    2017-01-01

    Cross-cultural impression management (IM) has not been considered much, which is remarkable given the fast rate at which the labor market is becoming multicultural. This study investigated whether ethnic minorities and majorities differed in their preference for IM-tactics and how this affected ethnic minorities' interview outcomes. A preliminary study (focus groups/survey) showed that ethnic minorities (i.e., Arab/Moroccans) preferred 'entitlements' whereas majorities (i.e., Flemish/Belgians) preferred 'opinion conformity' as IM-tactics. An experimental follow-up study among 163 ethnic majority raters showed no main effect of IM-tactics on interview ratings. Ethnic minorities' use of IM-tactics only affected interview ratings if rater characteristics were considered. Specifically, interview ratings were higher when ethnic minorities used opinion conformity (i.e., majority-preferred IM-tactic) and lower when minorities used entitlements (i.e., minority-preferred IM-tactic) if recruiters were high in social dominance orientation, and when they felt more experienced/proficient with interviewing. IM-tactics are a human capital factor that might help applicants to increase their job chances on the labor market. It is concluded that ethnic minority applicants' preferences for certain IM-tactics might lead to bias even in structured interview settings, but that this depends on ethnic majority recruiters' interview experience and ingroup/outgroup attitudes. Implications for research and practice are discussed.

  19. A Model of Organizational Context and Shared Decision Making: Application to LGBT Racial and Ethnic Minority Patients.

    PubMed

    DeMeester, Rachel H; Lopez, Fanny Y; Moore, Jennifer E; Cook, Scott C; Chin, Marshall H

    2016-06-01

    Shared decision making (SDM) occurs when patients and clinicians work together to reach care decisions that are both medically sound and responsive to patients' preferences and values. SDM is an important tenet of patient-centered care that can improve patient outcomes. Patients with multiple minority identities, such as sexual orientation and race/ethnicity, are at particular risk for poor SDM. Among these dual-minority patients, added challenges to clear and open communication include cultural barriers, distrust, and a health care provider's lack of awareness of the patient's minority sexual orientation or gender identity. However, organizational factors like a culture of inclusion and private space throughout the visit can improve SDM with lesbian, gay, bisexual, and transgender ("LGBT") racial/ethnic minority patients who have faced stigma and discrimination. Most models of shared decision making focus on the patient-provider interaction, but the health care organization's context is also critical. Context-an organization's structure and operations-can strongly influence the ability and willingness of patients and clinicians to engage in shared decision making. SDM is most likely to be optimal if organizations transform their contexts and patients and providers improve their communication. Thus, we propose a conceptual model that suggests ways in which organizations can shape their contextual structure and operations to support SDM. The model contains six drivers: workflows, health information technology, organizational structure and culture, resources and clinic environment, training and education, and incentives and disincentives. These drivers work through four mechanisms to impact care: continuity and coordination, the ease of SDM, knowledge and skills, and attitudes and beliefs. These mechanisms can activate clinicians and patients to engage in high-quality SDM. We provide examples of how specific contextual changes could make SDM more effective for LGBT racial/ethnic minority populations, focusing especially on transformations that would establish a safe environment, build trust, and decrease stigma.

  20. Problem Definition Study on 1,3-Dinitrobenzene, 1,3,5-Trinitrobenzene and Di-n-Propyl Adipate

    DTIC Science & Technology

    1979-11-01

    compound and not with the chemical structure. Simon and Blackman (1953) reported that the frond multiplication rate of Lemna minor at pH 5.1-5.4 was...Dinitrobenzere is also present in minor amounts in the TNT final product. Thus, 1,3-dinitrobenzene can also enter the environment from TNT blending and loading...reactions of 1,3-dinltrobenzene are expected to play only a minor role in the environmental fate of this chemical. Newell et aZ. (1976) reported that 1,3

  1. Women and Underrepresented Minorities in the it Workforce

    NASA Astrophysics Data System (ADS)

    Levin, Sharon G.; Stephan, Paula E.

    This study examines the composition of the information technology "IT" workforce and focuses on recruitment and retention and how they differ by gender and minority status. Data are from SESTAT, the largest nationally representative sample of college-educated scientists and engineers living in the United States. The data indicate that only about one in three individuals in the IT workforce in 1999 actually had a formal degree in an IT discipline; thus, recruitment from non-IT disciplines plays an important role in determining the size of the IT workforce. Similarly, retention, especially for women and underrepresented minorities, is very important. Indeed, the 1999 IT workforce would have been larger and even more balanced in terms of gender and minority status if women and underrepresented minorities had retention rates similar to that of their white male counterparts. Furthermore, women and underrepresented minorities have different recruitment and retention patterns than do men and whites. These differences persist even after controlling for variables such as family structure, age, citizenship status and field of training, gender, and race-ethnicity.

  2. Influence of indigenous minor components on fat crystal network of fully hydrogenated palm kernel oil and fully hydrogenated coconut oil.

    PubMed

    Chai, Xiu-Hang; Meng, Zong; Cao, Pei-Rang; Liang, Xin-Yu; Piatko, Michael; Campbell, Shawn; Koon Lo, Seong; Liu, Yuan-Fa

    2018-07-30

    Purification of triglycerides from fully hydrogenated palm kernel oil (FHPKO) and fully hydrogenated coconut oil (FHCNO) was performed by a chromatographic method. Lipid composition, thermal properties, polymorphism, isothermal crystallization behaviour, nanostructure and microstructure of FHPKO, FHPKO-triacylglycerol (TAG), FHCNO and FHCNO-TAG were evaluated. Removal of minor components had no effect on triglycerides composition. However, the presence of the minor components did increase the slip melting point and promote onset of crystallization. Furthermore, the thickness of the nanoscale crystals increased, and polymorphic transformation from β' to β occurred in FHPKO after the removal of minor components, and from α to β' in FHCNO. Sharp changes in the values of the Avrami constant K and exponent n suggested that the presence of minor components changed the crystal growth mechanism. The PLM results indicated that a coarser crystal structure with lower fractal dimension appeared after the removal of minor components from both FHPKO and FHCNO. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Modulation of a Pore in the Capsid of JC Polyomavirus Reduces Infectivity and Prevents Exposure of the Minor Capsid Proteins

    PubMed Central

    Nelson, Christian D. S.; Ströh, Luisa J.; Gee, Gretchen V.; O'Hara, Bethany A.; Stehle, Thilo

    2015-01-01

    ABSTRACT JC polyomavirus (JCPyV) infection of immunocompromised individuals results in the fatal demyelinating disease progressive multifocal leukoencephalopathy (PML). The viral capsid of JCPyV is composed primarily of the major capsid protein virus protein 1 (VP1), and pentameric arrangement of VP1 monomers results in the formation of a pore at the 5-fold axis of symmetry. While the presence of this pore is conserved among polyomaviruses, its functional role in infection or assembly is unknown. Here, we investigate the role of the 5-fold pore in assembly and infection of JCPyV by generating a panel of mutant viruses containing amino acid substitutions of the residues lining this pore. Multicycle growth assays demonstrated that the fitness of all mutants was reduced compared to that of the wild-type virus. Bacterial expression of VP1 pentamers containing substitutions to residues lining the 5-fold pore did not affect pentamer assembly or prevent association with the VP2 minor capsid protein. The X-ray crystal structures of selected pore mutants contained subtle changes to the 5-fold pore, and no other changes to VP1 were observed. Pore mutant pseudoviruses were not deficient in assembly, packaging of the minor capsid proteins, or binding to cells or in transport to the host cell endoplasmic reticulum. Instead, these mutant viruses were unable to expose VP2 upon arrival to the endoplasmic reticulum, a step that is critical for infection. This study demonstrated that the 5-fold pore is an important structural feature of JCPyV and that minor modifications to this structure have significant impacts on infectious entry. IMPORTANCE JCPyV is an important human pathogen that causes a severe neurological disease in immunocompromised individuals. While the high-resolution X-ray structure of the major capsid protein of JCPyV has been solved, the importance of a major structural feature of the capsid, the 5-fold pore, remains poorly understood. This pore is conserved across polyomaviruses and suggests either that these viruses have limited structural plasticity in this region or that this pore is important in infection or assembly. Using a structure-guided mutational approach, we showed that modulation of this pore severely inhibits JCPyV infection. These mutants do not appear deficient in assembly or early steps in infectious entry and are instead reduced in their ability to expose a minor capsid protein in the host cell endoplasmic reticulum. Our work demonstrates that the 5-fold pore is an important structural feature for JCPyV. PMID:25609820

  4. Costume and Music-Specific Dance: A Structure for Experimentation with Process and Technology

    ERIC Educational Resources Information Center

    Brown, Nathan; Dasen, Ann; Trommer-Beardslee, Heather

    2016-01-01

    This article describes how the authors completed a project at Central Michigan University (CMU) with undergraduate theater majors and minors and dance minors as part of the annual mainstage dance concert. Although the concert is predominantly choreographed and designed by CMU faculty, students are engaged in every step of the performance and…

  5. A Comparison of Ethnic Minority and Majority Students: Social and Academic Integration, and Quality of Learning

    ERIC Educational Resources Information Center

    Severiens, Sabine; Wolff, Rick

    2008-01-01

    This article examines students from ethnic minorities and majorities with regard to the relationships between their social and academic integration and their quality of learning. A total of 523 students at four universities completed a questionnaire: analyses of variance were used to examine mean differences, and structural equation modelling…

  6. Capital, Kinship, & White Privilege. Social & Cultural Influences upon the Minority Doctoral Experience in the Sciences

    ERIC Educational Resources Information Center

    Bancroft, Senetta

    2013-01-01

    In this article, the author presents a three-part analysis of the Ronald E. McNair Post-Baccalaureate Achievement Program, her own doctoral experience in a chemistry program, and similar experiences of other underrepresented minority (URM) graduate students found in the literature as examples of the social and cultural structures URMs experience…

  7. Despair Turned to Hope: A Theoretical Reconsideration of the Maori as a Caste Minority

    ERIC Educational Resources Information Center

    Motohashi, Ellen Preston

    2007-01-01

    In this article the author considers the impact of research and theory on non-dominant minority groups and the influence these have on shaping educators' understanding of the sociocultural, historical, and structural forces that impinge upon their work in the schools and communities they serve. Specifically, she reconsiders the constraints of John…

  8. Structural Relationships Between Minor and Major Proteins of Hepatitis B Surface Antigen

    PubMed Central

    Stibbe, Werner; Gerlich, Wolfram H.

    1983-01-01

    The minor glycoproteins from hepatitis B surface antigen, GP33 and GP36, contain at their carboxy-terminal part the sequence of the major protein P24. They have 55 additional amino acids at the amino-terminal part which are coded by the pre-S region of the viral DNA. Images PMID:6842680

  9. Family Collectivism and Minority Languages as Core Values of Culture among Ethnic Groups in Australia.

    ERIC Educational Resources Information Center

    Smolicz, Jerzy J.; Secombe, Margaret J.; Hudson, Dorothy M.

    2001-01-01

    Investigates the relative significance of family collectivism and minority languages as possible core values among four ethnic groups in the context of Australian society in which the English language and social structures of the majority group are dominant. Respondents were young adults drawn from Greek, Latvian, Italian, and Chinese-Australian…

  10. The Role of Cultural Diversity Climate in Recruitment, Promotion, and Retention of Faculty in Academic Medicine

    PubMed Central

    Price, Eboni G; Gozu, Aysegul; Kern, David E; Powe, Neil R; Wand, Gary S; Golden, Sherita; Cooper, Lisa A

    2005-01-01

    BACKGROUND Ethnic diversity among physicians may be linked to improved access and quality of care for minorities. Academic medical institutions are challenged to increase representation of ethnic minorities among health professionals. OBJECTIVES To explore the perceptions of physician faculty regarding the following: (1) the institution's cultural diversity climate and (2) facilitators and barriers to success and professional satisfaction in academic medicine within this context. DESIGN Qualitative study using focus groups and semi-structured interviews. PARTICIPANTS Nontenured physicians in the tenure track at the Johns Hopkins University School of Medicine. APPROACH Focus groups and interviews were audio-taped, transcribed verbatim, and reviewed for thematic content in a 3-stage independent review/adjudication process. RESULTS Study participants included 29 faculty representing 9 clinical departments, 4 career tracks, and 4 ethnic groups. In defining cultural diversity, faculty noted visible (race/ethnicity, foreign-born status, gender) and invisible (religion, sexual orientation) dimensions. They believe visible dimensions provoke bias and cumulative advantages or disadvantages in the workplace. Minority and foreign-born faculty report ethnicity-based disparities in recruitment and subtle manifestations of bias in the promotion process. Minority and majority faculty agree that ethnic differences in prior educational opportunities lead to disparities in exposure to career options, and qualifications for and subsequent recruitment to training programs and faculty positions. Minority faculty also describe structural barriers (poor retention efforts, lack of mentorship) that hinder their success and professional satisfaction after recruitment. To effectively manage the diversity climate, our faculty recommended 4 strategies for improving the psychological climate and structural diversity of the institution. CONCLUSIONS Soliciting input from faculty provides tangible ideas regarding interventions to improve an institution's diversity climate. PMID:16050848

  11. The role of cultural diversity climate in recruitment, promotion, and retention of faculty in academic medicine.

    PubMed

    Price, Eboni G; Gozu, Aysegul; Kern, David E; Powe, Neil R; Wand, Gary S; Golden, Sherita; Cooper, Lisa A

    2005-07-01

    Ethnic diversity among physicians may be linked to improved access and quality of care for minorities. Academic medical institutions are challenged to increase representation of ethnic minorities among health professionals. To explore the perceptions of physician faculty regarding the following: (1) the institution's cultural diversity climate and (2) facilitators and barriers to success and professional satisfaction in academic medicine within this context. Qualitative study using focus groups and semi-structured interviews. Nontenured physicians in the tenure track at the Johns Hopkins University School of Medicine. Focus groups and interviews were audio-taped, transcribed verbatim, and reviewed for thematic content in a 3-stage independent review/adjudication process. Study participants included 29 faculty representing 9 clinical departments, 4 career tracks, and 4 ethnic groups. In defining cultural diversity, faculty noted visible (race/ethnicity, foreign-born status, gender) and invisible (religion, sexual orientation) dimensions. They believe visible dimensions provoke bias and cumulative advantages or disadvantages in the workplace. Minority and foreign-born faculty report ethnicity-based disparities in recruitment and subtle manifestations of bias in the promotion process. Minority and majority faculty agree that ethnic differences in prior educational opportunities lead to disparities in exposure to career options, and qualifications for and subsequent recruitment to training programs and faculty positions. Minority faculty also describe structural barriers (poor retention efforts, lack of mentorship) that hinder their success and professional satisfaction after recruitment. To effectively manage the diversity climate, our faculty recommended 4 strategies for improving the psychological climate and structural diversity of the institution. Soliciting input from faculty provides tangible ideas regarding interventions to improve an institution's diversity climate.

  12. STRUCTURAL RACISM AND HEALTH INEQUITIES: Old Issues, New Directions.

    PubMed

    Gee, Gilbert C; Ford, Chandra L

    2011-04-01

    Racial minorities bear a disproportionate burden of morbidity and mortality. These inequities might be explained by racism, given the fact that racism has restricted the lives of racial minorities and immigrants throughout history. Recent studies have documented that individuals who report experiencing racism have greater rates of illnesses. While this body of research has been invaluable in advancing knowledge on health inequities, it still locates the experiences of racism at the individual level. Yet, the health of social groups is likely most strongly affected by structural, rather than individual, phenomena. The structural forms of racism and their relationship to health inequities remain under-studied. This article reviews several ways of conceptualizing structural racism, with a focus on social segregation, immigration policy, and intergenerational effects. Studies of disparities should more seriously consider the multiple dimensions of structural racism as fundamental causes of health disparities.

  13. Role of indirect readout mechanism in TATA box binding protein-DNA interaction.

    PubMed

    Mondal, Manas; Choudhury, Devapriya; Chakrabarti, Jaydeb; Bhattacharyya, Dhananjay

    2015-03-01

    Gene expression generally initiates from recognition of TATA-box binding protein (TBP) to the minor groove of DNA of TATA box sequence where the DNA structure is significantly different from B-DNA. We have carried out molecular dynamics simulation studies of TBP-DNA system to understand how the DNA structure alters for efficient binding. We observed rigid nature of the protein while the DNA of TATA box sequence has an inherent flexibility in terms of bending and minor groove widening. The bending analysis of the free DNA and the TBP bound DNA systems indicate presence of some similar structures. Principal coordinate ordination analysis also indicates some structural features of the protein bound and free DNA are similar. Thus we suggest that the DNA of TATA box sequence regularly oscillates between several alternate structures and the one suitable for TBP binding is induced further by the protein for proper complex formation.

  14. Promoting Pre-Exposure Prophylaxis to Prevent HIV Infections Among Sexual and Gender Minority Hispanics/Latinxs

    PubMed Central

    Page, Kathleen R.; Martinez, Omar; Nieves-Lugo, Karen; Zea, Maria Cecilia; Grieb, Suzanne Dolwick; Yamanis, Thespina J.; Spear, Kaitlin; Davis, Wendy W.

    2018-01-01

    Sexual and gender minority Hispanics/Latinxs (henceforth: Latinxs) continue to be disproportionately impacted by HIV/AIDS in the U.S. Pre-exposure prophylaxis (PrEP) is a biomedical prevention approach which holds significant promise for at risk and vulnerable populations. We discuss barriers and facilitators to uptake of PrEP among sexual and gender minority Latinxs living in the U.S. through an ecosocial lens that takes into account structural, community, and individual contexts. The impact of immigration status on PrEP uptake emerges as a major and recurrent theme that must be understood and addressed by HIV prevention programs aiming to promote an inclusive strategy for sexual and gender minority Latinxs living in the U.S. PMID:29068715

  15. Promoting Pre-exposure Prophylaxis to Prevent HIV Infections Among Sexual and Gender Minority Hispanics/Latinxs.

    PubMed

    Page, Kathleen R; Martinez, Omar; Nieves-Lugo, Karen; Zea, Maria Cecilia; Grieb, Suzanne Dolwick; Yamanis, Thespina J; Spear, Kaitlin; Davis, Wendy W

    2017-10-01

    Sexual and gender minority Hispanics/Latinxs (henceforth: Latinxs) continue to be disproportionately impacted by HIV/AIDS in the U.S. Pre-exposure prophylaxis (PrEP) is a biomedical prevention approach which holds significant promise for at risk and vulnerable populations. We discuss barriers and facilitators to uptake of PrEP among sexual and gender minority Latinxs living in the U.S. through an ecosocial lens that takes into account structural, community, and individual contexts. The impact of immigration status on PrEP uptake emerges as a major and recurrent theme that must be understood and addressed by HIV prevention programs aiming to promote an inclusive strategy for sexual and gender minority Latinxs living in the U.S.

  16. Heavy doping effects in high efficiency silicon solar cells

    NASA Technical Reports Server (NTRS)

    Lindholm, F. A.; Neugroschel, A.

    1985-01-01

    The use of a (silicon)/(heavily doped polysilicon)/(metal) structure to replace the conventional high-low junction (or back-surface-field, BSF) structure of silicon solar cells was examined. The results of an experimental study designed to explore both qualitatively and quantitatively the mechanism of the improved current gain in bipolar transistors with polysilicon emitter contact are presented. A reciprocity theorem is presented that relates the short circuit current of a device, induced by a carrier generation source, to the minority carrier Fermi level in the dark. A method for accurate measurement of minority-carrier diffusion coefficients in silicon is described.

  17. Sequence-dependent effects in drug-DNA interaction: the crystal structure of Hoechst 33258 bound to the d(CGCAAATTTGCG)2 duplex.

    PubMed Central

    Spink, N; Brown, D G; Skelly, J V; Neidle, S

    1994-01-01

    The bis-benzimidazole drug Hoechst 33258 has been co-crystallized with the dodecanucleotide sequence d(CGCAAATTTGCG)2. The structure has been solved by molecular replacement and refined to an R factor of 18.5% for 2125 reflections collected on a Xentronics area detector. The drug is bound in the minor groove, at the five base-pair site 5'-ATTTG and is in a unique orientation. This is displaced by one base pair in the 5' direction compared to previously-determined structures of this drug with the sequence d(CGCGAATTCGCG)2. Reasons for this difference in behaviour are discussed in terms of several sequence-dependent structural features of the DNA, with particular reference to differences in propeller twist and minor-groove width. Images PMID:7515488

  18. The Impact of Minority Stress on Mental Health and Substance Use Among Sexual Minority Women

    PubMed Central

    Lehavot, Keren; Simoni, Jane M.

    2014-01-01

    Objective We examined the direct and indirect impact of minority stress on mental health and substance use among sexual minority women. Method A combination of snowball and targeted sampling strategies was used to recruit lesbian and bisexual women (N = 1,381) for a cross-sectional, online survey. Participants (M age = 33.54 years; 74% White) completed a questionnaire assessing gender expression, minority stressors (i.e., victimization, internalized homophobia, and concealment), social–psychological resources (i.e., social support, spirituality), and health-related outcomes. We used structural equation modeling to test associations among these factors, with gender expression as an antecedent and social–psychological resources as a mediator between minority stress and health. Results The final model demonstrated acceptable fit, χ2(79) = 414.00, p < .05, confirmatory fit index = .93, Tucker–Lewis index = .91, standardized root-mean-square residual = .05, root-mean-square error of approximation = .06, accounting for significant portions of the variance in mental health problems (56%) and substance use (14%), as well as the mediator social–psychological resources (24%). Beyond indirect effects of minority stress on health outcomes, direct links emerged between victimization and substance use and between internalized homophobia and substance use. Conclusions Findings indicate a significant impact of minority stressors and social–psychological resources on mental health and substance use among sexual minority women. The results improve understanding of the distinct role of various minority stressors and their mechanisms on health outcomes. Health care professionals should assess for minority stress and coping resources and refer for evidence-based psychosocial treatments. PMID:21341888

  19. Minority Stress Experiences and Psychological Well-Being: The Impact of Support from and Connection to Social Networks within the Los Angeles House and Ball Communities

    PubMed Central

    Wong, Carolyn F.; Schrager, Sheree M.; Holloway, Ian W.; Meyer, Ilan H.; Kipke, Michele D.

    2013-01-01

    African American young men who have sex with men (AAYMSM) from the House and Ball communities are at high risk for HIV infection. Because these communities are not only sources of risk, but also support for AAYMSM, researchers must also consider the resources these communities possess. This knowledge will assist in the formulation of more effective prevention strategies and intervention approaches. Using Minority Stress Theory as a framework, the current study illustrates the impact minority stress has on the psychological well-being of a sample of MSM from the Los Angeles House and Ball communities and investigates how these factors affect the relationship between minority stress and psychological well-being. Surveys were administered to participants over the course of a year. Structural equation modeling was used to estimate a model of the associations between minority stressors, support, connection to social network, and psychological well-being/distress (N=233). Results indicated significant associations between different sources of minority stress, including distal minority stress (e.g., racism, homophobia), gay identification, and internalized homophobia. Minority stressors were in turn significantly associated with greater distress. However, greater instrumental support significantly reduced the effects of distal minority stress on distress. Greater connection to social network also significantly reduced stress associated with gay identification on distress. Findings captured the diverse sources of minority stress faced by this population and how these stressors are interrelated to impact mental health. Results also illustrate how support from and connection to social networks can reduce the negative impact of minority stress experiences. PMID:23412944

  20. The impact of minority stress on mental health and substance use among sexual minority women.

    PubMed

    Lehavot, Keren; Simoni, Jane M

    2011-04-01

    We examined the direct and indirect impact of minority stress on mental health and substance use among sexual minority women. A combination of snowball and targeted sampling strategies was used to recruit lesbian and bisexual women (N = 1,381) for a cross-sectional, online survey. Participants (M age = 33.54 years; 74% White) completed a questionnaire assessing gender expression, minority stressors (i.e., victimization, internalized homophobia, and concealment), social-psychological resources (i.e., social support, spirituality), and health-related outcomes. We used structural equation modeling to test associations among these factors, with gender expression as an antecedent and social-psychological resources as a mediator between minority stress and health. The final model demonstrated acceptable fit, χ²(79) = 414.00, p < .05, confirmatory fit index = .93, Tucker-Lewis index = .91, standardized root-mean-square residual = .05, root-mean-square error of approximation = .06, accounting for significant portions of the variance in mental health problems (56%) and substance use (14%), as well as the mediator social-psychological resources (24%). Beyond indirect effects of minority stress on health outcomes, direct links emerged between victimization and substance use and between internalized homophobia and substance use. Findings indicate a significant impact of minority stressors and social-psychological resources on mental health and substance use among sexual minority women. The results improve understanding of the distinct role of various minority stressors and their mechanisms on health outcomes. Health care professionals should assess for minority stress and coping resources and refer for evidence-based psychosocial treatments. (c) 2011 APA, all rights reserved.

  1. Active Summers Matter: Evaluation of a Community-Based Summertime Program Targeting Obesogenic Behaviors of Low-Income, Ethnic Minority Girls

    ERIC Educational Resources Information Center

    Bohnert, Amy M.; Ward, Amanda K.; Burdette, Kimberly A.; Silton, Rebecca L.; Dugas, Lara R.

    2014-01-01

    Low-income minority females are disproportionately affected by obesity. The relevance of summer months to weight gain is often overlooked. Some evidence suggests that summer programming, such as day camps, may offer increased opportunities for structured physical activities resulting in less weight gain. This study examined the effectiveness of…

  2. Creating Culturally Responsive Environments: Ethnic Minority Teachers' Constructs of Cultural Diversity in Hong Kong Secondary Schools

    ERIC Educational Resources Information Center

    Hue, Ming-tak; Kennedy, Kerry John

    2014-01-01

    One of the challenges facing Hong Kong schools is the growing cultural diversity of the student population that is a result of the growing number of ethnic minority students in the schools. This study uses semi-structured interviews with 12 American, Canadian, Indian, Nepalese and Pakistani teachers working in three secondary schools in the public…

  3. Careers "From" but Not "In" Science: Why Are Aspirations to Be a Scientist Challenging for Minority Ethnic Students?

    ERIC Educational Resources Information Center

    Wong, Billy

    2015-01-01

    The importance of science to the economy and for the progression of society is widely acknowledged. Yet, there are concerns that minority ethnic students in the UK are underrepresented, and even excluded, from post-compulsory science education and careers "in" science. Drawing on an exploratory study of 46 semi-structured interviews with…

  4. Against the Tide: Household Structure, Opportunities, and Outcomes among White and Minority Youth

    ERIC Educational Resources Information Center

    Hill, Carolyn J.; Holzer, Harry J.; Chen, Henry

    2008-01-01

    Gaps in educational and employment outcomes persist (and in some cases are growing) among various groups of young adults in the United States. Particularly notable are the gaps that exist between minority young adults--especially black young adults--and their white counterparts. One oft-cited reason for this trend is the growing number of youth…

  5. Populations of the Minor α-Conformation in AcGXGNH2 and the α-Helical Nucleation Propensities

    NASA Astrophysics Data System (ADS)

    Zhou, Yanjun; He, Liu; Zhang, Wenwen; Hu, Jingjing; Shi, Zhengshuang

    2016-06-01

    Intrinsic backbone conformational preferences of different amino acids are important for understanding the local structure of unfolded protein chains. Recent evidence suggests α-structure is relatively minor among three major backbone conformations for unfolded proteins. The α-helices are the dominant structures in many proteins. For these proteins, how could the α-structures occur from the least in unfolded to the most in folded states? Populations of the minor α-conformation in model peptides provide vital information. Reliable determination of populations of the α-conformers in these peptides that exist in multiple equilibriums of different conformations remains a challenge. Combined analyses on data from AcGXPNH2 and AcGXGNH2 peptides allow us to derive the populations of PII, β and α in AcGXGNH2. Our results show that on average residue X in AcGXGNH2 adopt PII, β, and α 44.7%, 44.5% and 10.8% of time, respectively. The contents of α-conformations for different amino acids define an α-helix nucleation propensity scale. With derived PII, β and α-contents, we can construct a free energy-conformation diagram on each AcGXGNH2 in aqueous solution for the three major backbone conformations. Our results would have broad implications on early-stage events of protein folding.

  6. Toward a Model of Social Influence that Explains Minority Student Integration into the Scientific Community

    PubMed Central

    Estrada, Mica; Woodcock, Anna; Hernandez, Paul R.; Schultz, P. Wesley

    2010-01-01

    Students from several ethnic minority groups are underrepresented in the sciences, such that minority students more frequently drop out of the scientific career path than non-minority students. Viewed from a perspective of social influence, this pattern suggests that minority students do not integrate into the scientific community at the same rate as non-minority students. Kelman (1958, 2006) describes a tripartite integration model of social influence (TIMSI) by which a person orients to a social system. To test if this model predicts integration into the scientific community, we conducted analyses of data from a national panel of minority science students. A structural equation model framework showed that self-efficacy (operationalized consistent with Kelman’s ‘rule-orientation’) predicted student intentions to pursue a scientific career. However, when identification as a scientist and internalization of values are added to the model, self-efficacy becomes a poorer predictor of intention. Additional mediation analyses support the conclusion that while having scientific self-efficacy is important, identifying with and endorsing the values of the social system reflect a deeper integration and more durable motivation to persist as a scientist. PMID:21552374

  7. Issues in educating health professionals to meet the diverse needs of patients and other service users from ethnic minority groups.

    PubMed

    Chevannes, Mel

    2002-08-01

    The main aim of the study was to undertake training needs analysis among a multi-professional group for the purpose of improving care for ethnic minority patients and other service users. Evidence from the literature identifies that some of the explanations advanced for the failure of health professionals to meet the needs of ethnic minorities include lack of understanding of cultural diversities, racism, racial stereotyping, lack of knowledge, exclusivity, and ethnocentrism. While these issues have been addressed in different countries, little work has been carried out to examine these from the perspective of health professionals caring for ethnic minorities. This study is therefore an attempt to find out what health professionals know about caring for patients and other service users from minority ethnic groups and their perception of training needs in this area of work. A pre- and post-training design phase structured the qualitative approach. A purposive sample of individuals working across five health service organizations located in a multi-racial city yielded a multi-professional group of participants. Views of 22 participants were obtained by semi-structured interviews at a pretraining phase. Training needs of health professionals drew on Walklin's (1992) six stages used to structure data collection, data analysis and delivery of training. The post-training phase used questionnaires to evaluate immediate learning that based on a 4-week period of reflection and applied to practice. The questionnaires were complemented by a facilitator-lead focus group. The majority of the participants confirmed that no attention was given in their initial education to the health care needs of minority ethnic groups. Instead, participants engaged in self-initiated learning to improve their knowledge and understanding. The issue of communication was viewed with dissatisfaction and seen as affecting the sufficiency of caring for these patients. All participants rated meeting the needs of ethnic minorities as very important and believed that they had gained a better understanding of the concepts of ethnicity and race and resources available in local communities as a result of the training. They also reported changes in thinking about ethnic minorities and had started to acquire greater confidence to engage with colleagues about different cultural values and practices and the implications of these for caring. While a quarter of the participants had transferred some learning to practice, the majority were not able to bring about any change. This majority response challenged the sustainability of learning about ethnic minorities when training takes place away from the context in which professionals practise. Training embedded in clinical and nonclinical environment where patients and other service users and professionals interact is offered as a major finding.

  8. Manipulative interplay of two adozelesin molecules with d(ATTAAT)₂achieving ligand-stacked Watson-Crick and Hoogsteen base-paired duplex adducts.

    PubMed

    Hopton, Suzanne R; Thompson, Andrew S

    2011-05-17

    Previous structural studies of the cyclopropapyrroloindole (CPI) antitumor antibiotics have shown that these ligands bind covalently edge-on into the minor groove of double-stranded DNA. Reversible covalent modification of the DNA via N3 of adenine occurs in a sequence-specific fashion. Early nuclear magnetic resonance and molecular modeling studies with both mono- and bis-alkylating ligands indicated that the ligands fit tightly within the minor groove, causing little distortion of the helix. In this study, we propose a new binding model for several of the CPI-based analogues, in which the aromatic secondary rings form π-stacked complexes within the minor groove. One of the adducts, formed with adozelesin and the d(ATTAAT)(2) sequence, also demonstrates the ability of these ligands to manipulate the DNA of the binding site, resulting in a Hoogsteen base-paired adduct. Although this type of base pairing has been previously observed with the bisfunctional CPI analogue bizelesin, this is the first time that such an observation has been made with a monoalkylating nondimeric analogue. Together, these results provide a new model for the design of CPI-based antitumor antibiotics, which also has a significant bearing on other structurally related and structurally unrelated minor groove-binding ligands. They indicate the dynamic nature of ligand-DNA interactions, demonstrating both DNA conformational flexibility and the ability of two DNA-bound ligands to interact to form stable covalent modified complexes.

  9. Thermal-Structures and Materials Testing Laboratory

    NASA Technical Reports Server (NTRS)

    Teate, Anthony A.

    1997-01-01

    Since its inception and successful implementation in 1997 at James Madison University, the Thermal Structures and Materials Testing Laboratory (T-SaMTL) funded by the NASA Langley Research Center is evolving into one of the University's premier and exemplary efforts to increase minority representation in the sciences and mathematics. Serving ten (10) students and faculty directly and almost fifty (50) students indirectly, T-SAMTL, through its recruitment efforts, workshops, mentoring program, tutorial services and its research and computational laboratories has marked the completion of the first year with support from NASA totaling $ 100,000. Beginning as an innovative academic research and mentoring program for underrepresented minority science and mathematics students, the program now boasts a constituency which consists of 50% graduating seniors in the spring of 1998 with 50% planning to go to graduate school. The program's intent is to increase the number of underrepresented minorities who receive doctoral degrees in the sciences by initiating an academically enriched research program aimed at strengthening the academic and self actualization skills of undergraduate students with the potential to pursue doctoral study in the sciences. The program provides financial assistance, academic enrichment, and professional and personal development support for minority students who demonstrate the potential and strong desire to pursue careers in the sciences and mathematics. James Madison University was awarded the first $100,000, in April 1997, by The NASA Langley Research Center for establishment and support of its Thermal Structures and Materials Testing

  10. Thermodynamic Characterization of DNA with 3-Deazaadenine and 3-Methyl-3-Deazaadenine Substitutions: The Effect of Placing a Hydrophobic Group in the Minor Groove of DNA

    PubMed Central

    Ganguly, Manjori; Wang, Ruo-Wen; Marky, Luis A.; Gold, Barry

    2010-01-01

    In many high-resolution structures of DNA there are ordered waters associated with the floor of the minor groove and extending outward in several layers. It is thought that this hydration structure, along with cations, reduces the Coulombic repulsion of the interstrand phosphates. In previous studies, the replacement of the 3-N atom of adenine with a C-H to afford 3-deazaadenine was shown to decrease the thermodynamic stability of DNA via a reduction in the enthalpic term. Using spectroscopic and calorimetric methods, we report herein a rigorous examination of the thermodynamics of DNA with 3-deazaadenine modifications, and report for the first time how the presence of a minor groove methyl group, i.e., 3-methyl-3-deazaadeine, affects DNA stability, hydration and cation binding. The methylation of adenine at the N3-position to yield N3-methyladenine represents an important reaction in the toxicity of many anticancer compounds. This minor groove lesion is unstable and cannot be readily studied in terms of its effect on DNA stability or structure. Our studies show that 3-methyl-3-deazaadenine, an isostere of N3-methyladenine, significantly destabilizes DNA (ΔΔG > 4 kcal•mol−1) due to a significant drop in the enthalpy (ΔH) term, which is associated with a lower hydration of the duplex relative to the unfolded state. PMID:20469878

  11. Structural stigma and the health and wellbeing of Australian LGB populations: Exploiting geographic variation in the results of the 2017 same-sex marriage plebiscite.

    PubMed

    Perales, Francisco; Todd, Abram

    2018-05-14

    Lesbian, gay, or bisexual (LGB) people experience poorer life outcomes than heterosexual people, with ongoing debates about the aetiology of these differences. Minority stress theory draws attention to the importance of structural stigma, which concerns hostile social environments for sexual minorities that constrain their opportunity structures. Yet few studies have operationalised structural stigma and tested its influence, with most focusing on the US context; even fewer studies examine the underlying mechanisms. This study expands the available evidence to Australia, which constitutes an interesting case study due to the implementation in late 2017 of a national postal plebiscite on same-sex marriage legislation. It also adds to knowledge by theorising and testing the mediating role of perceived social support in explaining the association between structural stigma and the life outcomes of LGB people. The analyses leverage geographical variation at the electorate level (n = 150) in the share of 'No' voters in the plebiscite as a measure of structural stigma. This aggregate-level information is merged to individual-level data from the Household, Income and Labour Dynamics in Australia Survey, a large, national probability sample (n∽15,000). Multilevel regression models yield results which are consistent with minority stress theory and previous US scholarship: LGB people report comparatively worse life satisfaction, mental health and overall health in constituencies with higher shares of 'No' voters, controlling for a large set of individual- and aggregate-level confounds. Perceived social support mediates a large portion of the effects of structural stigma on LGB outcomes. These findings have significant implications for policy and practice, highlighting the need for interventions aimed at reducing community levels of structural stigma and increasing social support to LGB populations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. 7 CFR 658.3 - Applicability and exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... construction of on-farm structures necessary for farm operations. Federal agencies can obtain assistance from... structures and sites converted prior to the time of an application for assistance from a Federal agency, including assistance and actions related to the construction of minor new ancillary structures (such as...

  13. 7 CFR 658.3 - Applicability and exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... construction of on-farm structures necessary for farm operations. Federal agencies can obtain assistance from... structures and sites converted prior to the time of an application for assistance from a Federal agency, including assistance and actions related to the construction of minor new ancillary structures (such as...

  14. 7 CFR 658.3 - Applicability and exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... construction of on-farm structures necessary for farm operations. Federal agencies can obtain assistance from... structures and sites converted prior to the time of an application for assistance from a Federal agency, including assistance and actions related to the construction of minor new ancillary structures (such as...

  15. 7 CFR 658.3 - Applicability and exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... construction of on-farm structures necessary for farm operations. Federal agencies can obtain assistance from... structures and sites converted prior to the time of an application for assistance from a Federal agency, including assistance and actions related to the construction of minor new ancillary structures (such as...

  16. 7 CFR 658.3 - Applicability and exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... construction of on-farm structures necessary for farm operations. Federal agencies can obtain assistance from... structures and sites converted prior to the time of an application for assistance from a Federal agency, including assistance and actions related to the construction of minor new ancillary structures (such as...

  17. Crystal Structure of the Minor Pilin CofB, the Initiator of CFA/III Pilus Assembly in Enterotoxigenic Escherichia coli*

    PubMed Central

    Kolappan, Subramania; Ng, Dixon; Yang, Guixiang; Harn, Tony; Craig, Lisa

    2015-01-01

    Type IV pili are extracellular polymers of the major pilin subunit. These subunits are held together in the pilus filament by hydrophobic interactions among their N-terminal α-helices, which also anchor the pilin subunits in the inner membrane prior to pilus assembly. Type IV pilus assembly involves a conserved group of proteins that span the envelope of Gram-negative bacteria. Among these is a set of minor pilins, so named because they share their hydrophobic N-terminal polymerization/membrane anchor segment with the major pilins but are much less abundant. Minor pilins influence pilus assembly and retraction, but their precise functions are not well defined. The Type IV pilus systems of enterotoxigenic Escherichia coli and Vibrio cholerae are among the simplest of Type IV pilus systems and possess only a single minor pilin. Here we show that the enterotoxigenic E. coli minor pilins CofB and LngB are required for assembly of their respective Type IV pili, CFA/III and Longus. Low levels of the minor pilins are optimal for pilus assembly, and CofB can be detected in the pilus fraction. We solved the 2.0 Å crystal structure of N-terminally truncated CofB, revealing a pilin-like protein with an extended C-terminal region composed of two discrete domains connected by flexible linkers. The C-terminal region is required for CofB to initiate pilus assembly. We propose a model for CofB-initiated pilus assembly with implications for understanding filament growth in more complex Type IV pilus systems as well as the related Type II secretion system. PMID:26324721

  18. Crystal Structure of the Minor Pilin CofB, the Initiator of CFA/III Pilus Assembly in Enterotoxigenic Escherichia coli.

    PubMed

    Kolappan, Subramania; Ng, Dixon; Yang, Guixiang; Harn, Tony; Craig, Lisa

    2015-10-23

    Type IV pili are extracellular polymers of the major pilin subunit. These subunits are held together in the pilus filament by hydrophobic interactions among their N-terminal α-helices, which also anchor the pilin subunits in the inner membrane prior to pilus assembly. Type IV pilus assembly involves a conserved group of proteins that span the envelope of Gram-negative bacteria. Among these is a set of minor pilins, so named because they share their hydrophobic N-terminal polymerization/membrane anchor segment with the major pilins but are much less abundant. Minor pilins influence pilus assembly and retraction, but their precise functions are not well defined. The Type IV pilus systems of enterotoxigenic Escherichia coli and Vibrio cholerae are among the simplest of Type IV pilus systems and possess only a single minor pilin. Here we show that the enterotoxigenic E. coli minor pilins CofB and LngB are required for assembly of their respective Type IV pili, CFA/III and Longus. Low levels of the minor pilins are optimal for pilus assembly, and CofB can be detected in the pilus fraction. We solved the 2.0 Å crystal structure of N-terminally truncated CofB, revealing a pilin-like protein with an extended C-terminal region composed of two discrete domains connected by flexible linkers. The C-terminal region is required for CofB to initiate pilus assembly. We propose a model for CofB-initiated pilus assembly with implications for understanding filament growth in more complex Type IV pilus systems as well as the related Type II secretion system. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  19. Structural and kinetic studies of a novel nerol dehydrogenase from Persicaria minor, a nerol-specific enzyme for citral biosynthesis.

    PubMed

    Tan, Cheng Seng; Hassan, Maizom; Mohamed Hussein, Zeti Azura; Ismail, Ismanizan; Ho, Kok Lian; Ng, Chyan Leong; Zainal, Zamri

    2018-02-01

    Geraniol degradation pathway has long been elucidated in microorganisms through bioconversion studies, yet weakly characterised in plants; enzyme with specific nerol-oxidising activity has not been reported. A novel cDNA encodes nerol dehydrogenase (PmNeDH) was isolated from Persicaria minor. The recombinant PmNeDH (rPmNeDH) is a homodimeric enzyme that belongs to MDR (medium-chain dehydrogenases/reductases) superfamily that catalyses the first oxidative step of geraniol degradation pathway in citral biosynthesis. Kinetic analysis revealed that rPmNeDH has a high specificity for allylic primary alcohols with backbone ≤10 carbons. rPmNeDH has ∼3 fold higher affinity towards nerol (cis-3,7-dimethyl-2,6-octadien-1-ol) than its trans-isomer, geraniol. To our knowledge, this is the first alcohol dehydrogenase with higher preference towards nerol, suggesting that nerol can be effective substrate for citral biosynthesis in P. minor. The rPmNeDH crystal structure (1.54 Å) showed high similarity with enzyme structures from MDR superfamily. Structure guided mutation was conducted to describe the relationships between substrate specificity and residue substitutions in the active site. Kinetics analyses of wild-type rPmNeDH and several active site mutants demonstrated that the substrate specificity of rPmNeDH can be altered by changing any selected active site residues (Asp 280 , Leu 294 and Ala 303 ). Interestingly, the L294F, A303F and A303G mutants were able to revamp the substrate preference towards geraniol. Furthermore, mutant that exhibited a broader substrate range was also obtained. This study demonstrates that P. minor may have evolved to contain enzyme that optimally recognise cis-configured nerol as substrate. rPmNeDH structure provides new insights into the substrate specificity and active site plasticity in MDR superfamily. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  20. A last stand in the Po valley: genetic structure and gene flow patterns in Ulmus minor and U. pumila

    PubMed Central

    Bertolasi, B.; Leonarduzzi, C.; Piotti, A.; Leonardi, S.; Zago, L.; Gui, L.; Gorian, F.; Vanetti, I.; Binelli, G.

    2015-01-01

    Background and Aims Ulmus minor has been severely affected by Dutch elm disease (DED). The introduction into Europe of the exotic Ulmus pumila, highly tolerant to DED, has resulted in it widely replacing native U. minor populations. Morphological and genetic evidence of hybridization has been reported, and thus there is a need for assessment of interspecific gene flow patterns in natural populations. This work therefore aimed at studying pollen gene flow in a remnant U. minor stand surrounded by trees of both species scattered across an agricultural landscape. Methods All trees from a small natural stand (350 in number) and the surrounding agricultural area within a 5-km radius (89) were genotyped at six microsatellite loci. Trees were morphologically characterized as U. minor, U. pumila or intermediate phenotypes, and morphological identification was compared with Bayesian clustering of genotypes. For paternity analysis, seeds were collected in two consecutive years from 20 and 28 mother trees. Maximum likelihood paternity assignment was used to elucidate intra- and interspecific gene flow patterns. Key Results Genetic structure analyses indicated the presence of two genetic clusters only partially matching the morphological identification. The paternity analysis results were consistent between the two consecutive years of sampling and showed high pollen immigration rates (∼0·80) and mean pollination distances (∼3 km), and a skewed distribution of reproductive success. Few intercluster pollinations and putative hybrid individuals were found. Conclusions Pollen gene flow is not impeded in the fragmented agricultural landscape investigated. High pollen immigration and extensive pollen dispersal distances are probably counteracting the potential loss of genetic variation caused by isolation. Some evidence was also found that U. minor and U. pumila can hybridize when in sympatry. Although hybridization might have beneficial effects on both species, remnant U. minor populations represent a valuable source of genetic diversity that needs to be preserved. PMID:25725008

  1. Grouping Within Algebra I: A Structural Sieve With Powerful Effects for Low-Income, Minority, and Immigrant Students

    ERIC Educational Resources Information Center

    Paul, Faith G.

    2005-01-01

    A key element in educational reform has been to increase mathematical proficiency. We look at how five urban high schools with virtually all low-income, minority, and immigrant students have arranged for students to take algebra I, and we examine the course enrollments and grades of these student in the core college prep courses. Both preparation…

  2. Perturbations in DNA structure upon interaction with porphyrins revealed by chemical probes, DNA footprinting and molecular modelling.

    PubMed

    Ford, K G; Neidle, S

    1995-06-01

    The interactions of several porphyrins with a 74 base-pair DNA sequence have been examined by footprinting and chemical protection methods. Tetra-(4-N-methyl-(pyridyl)) porphyrin (TMPy), two of its metal complexes and tetra-(4-trimethylanilinium) porphyrin (TMAP) bind to closely similar AT-rich sequences. The three TMPy ligands produce modest changes in DNA structure and base accessibility on binding, in contrast to the large-scale conformational changes observed with TMAP. Molecular modelling studies have been performed on TMPy and TMAP bound in the AT-rich minor groove of an oligonucleotide. These have shown that significant structural change is needed to accommodate the bulky trimethyl substituent groups of TMAP, in contrast to the facile minor groove fit of TMPy.

  3. Percutaneous Radiofrequency Ablation of a Small Renal Mass Complicated by Appendiceal Perforation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boone, Judith, E-mail: j.boone@amc.uva.nl; Bex, Axel, E-mail: a.bex@nki.nl; Prevoo, Warner, E-mail: w.prevoo@nki.nl

    2012-06-15

    Percutaneous radiofrequency ablation (RFA) has gained wide acceptance as nephron-sparing therapy for small renal masses in select patients. Generally, it is a safe procedure with minor morbidity and acceptable short-term oncologic outcome. However, as a result of the close proximity of vital structures, such as the bowel, ureter, and large vessels, to the ablative field, complications regarding these structures may occur. This is the first article describing appendiceal perforation as a complication of computed tomography-guided RFA despite hydrodissection. When performing this innovative and promising procedure one should be aware of the possibility of particular minor and even major complications.

  4. Chlorophyll Catabolites in Senescent Leaves of the Plum Tree (Prunus domestica).

    PubMed

    Erhart, Theresia; Mittelberger, Cecilia; Vergeiner, Clemens; Scherzer, Gerhard; Holzner, Barbara; Robatscher, Peter; Oberhuber, Michael; Kräutler, Bernhard

    2016-11-01

    In cold extracts of senescent leaves of the plum tree (Prunus domestica ssp. domestica), six colorless non-fluorescent chlorophyll catabolites (NCCs) were characterized, named Pd-NCCs. In addition, several minor NCC fractions were tentatively classified. The structure of the most polar one of the NCCs, named Pd-NCC-32, featured an unprecedented twofold glycosidation pattern. Three of the NCCs are also functionalized at their 3 2 -position by a glucopyranosyl group. In addition, two of these glycosidated NCCs carry a dihydroxyethyl group at their 18-position. In the polar Pd-NCC-32, the latter group is further glycosidated at the terminal 18 2 -position. Four other major Pd-NCCs and one minor Pd-NCC were identified with five NCCs from higher plants known to belong to the 'epi'-series. In addition, tentative structures were derived for two minor fractions, classified as yellow chlorophyll catabolites, which represented (formal) oxidation products of two of the observed Pd-NCCs. The chlorophyll catabolites in leaves of plum feature the same basic structural pattern as those found in leaves of apple and pear trees. © 2016 The Authors. Chemistry & Biodiversity Published by Wiley-VHCA AG, Zurich, Switzerland.

  5. Macro-Level Approaches to HIV Prevention Among Ethnic Minority Youth

    PubMed Central

    Prado, Guillermo; Lightfoot, Marguerita; Brown, C. Hendricks

    2013-01-01

    The HIV epidemic continues to disproportionately affect ethnic minority youth. These disconcerting health disparities indicate that although existing HIV preventive strategies for ethnic minority youth have been efficacious, they have not significantly reduced the impact of the epidemic in this population. Macro-level interventions, such as structural or policy interventions, have the potential to impact the HIV epidemic at a population level, and thus reduce the HIV health disparities that exist among ethnic minority youth and other segments of the U.S. population. This article calls for a paradigm shift to develop, evaluate, and disseminate interventions that target upstream/macro-level factors or that, at a minimum, integrate both a macro and individual level perspective. The article also discusses the challenges in developing and evaluating such interventions. Psychologists and other behavioral scientists can play a critical role in reducing the impact of HIV on ethnic minority youth by integrating macro-level approaches to future HIV prevention strategies. PMID:23688095

  6. Human development XIII: the connection between the structure of the overtone system and the tone language of music. Some implications for our understanding of the human brain.

    PubMed

    Ventegodt, Søren; Hermansen, Tyge Dahl; Kandel, Isack; Merrick, Joav

    2008-07-13

    The functioning brain behaves like one highly-structured, coherent, informational field. It can be popularly described as a "coherent ball of energy", making the idea of a local highly-structured quantum field that carries the consciousness very appealing. If that is so, the structure of the experience of music might be a quite unique window into a hidden quantum reality of the brain, and even of life itself. The structure of music is then a mirror of a much more complex, but similar, structure of the energetic field of the working brain. This paper discusses how the perception of music is organized in the human brain with respect to the known tone scales of major and minor. The patterns used by the brain seem to be similar to the overtones of vibrating matter, giving a positive experience of harmonies in major. However, we also like the minor scale, which can explain brain patterns as fractal-like, giving a symmetric "downward reflection" of the major scale into the minor scale. We analyze the implication of beautiful and ugly tones and harmonies for the model. We conclude that when it comes to simple perception of harmonies, the most simple is the most beautiful and the most complex is the most ugly, but in music, even the most disharmonic harmony can be beautiful, if experienced as a part of a dynamic release of musical tension. This can be taken as a general metaphor of painful, yet meaningful, and developing experiences in human life.

  7. Procurement Opportunitites in: Afghanistan and the Central Asian States (CAS)

    DTIC Science & Technology

    2012-08-01

    barriers) Furniture (office and household) Prefabricated Structures (CONEXs, containerized housing units, re-locatable buildings) Office Supplies... Concrete Foundation and Structure Road Support Activities Minor Building Renovation Water and Sewer Line and Related Construction Heavy and Civil

  8. Flight service evaluation of Kevlar-49 epoxy composite panels in wide-bodied commercial transport aircraft

    NASA Technical Reports Server (NTRS)

    Stone, R. H.

    1982-01-01

    Kevlar-49 fairing panels, installed as flight service components on three l-1011's, were inspected after 8 years service. The fairings had accumulated a total of 62,000 hours, with one ship set having 20,850 hours service. Kevlar-49 components were found to be performing satisfactorily in service with no major problems. The only defects noted were minor impact damage, a few minor disbonds and a minor degree of fastener hole fraying and elongation. The service history to date indicates that Kevlar-49 epoxy composite materials have satisfactory service characteristics for use in aircraft secondary structures.

  9. A study of the minority college programs at the NASA Johnson Space Center

    NASA Technical Reports Server (NTRS)

    Tryman, Mfanya Donald

    1987-01-01

    Research programs in science and engineering at predominantly black and white universities which assist in training and furthering the capabilities of minorities in the field, are examined. The Minority Graduate Researcher's Program and the Historically Black College and University Program were the focus of this research. The objectives included investigating the organizational structure and processes of the programs, how they are run, how they differ, defining particular administrative tasks for these programs, the collection of data related to these programs, and recommending ways in which these programs can be improved for greater efficiency and effectiveness through the Equal Opportunity Programs Office.

  10. Race, culture and ethnicity in minority research: a critical discussion.

    PubMed

    Dein, Simon

    2006-01-01

    Race and ethnicity are terms commonly used in ethnic minority research. Both these terms present a number of problems in terms of definition and classification. It is argued here that there is a need to move beyond essentialised concepts of race and ethnicity to examine the socio-political processes which relate to their social construction and the ways in which these terms articulate with other categories such as social class and gender and structure social relationships. The implications of the social constructionist position are discussed specifically in relation to the use of interpreters and ethnic matching of researcher and respondent in qualitative research on ethnic minorities.

  11. Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system in Florida and parts of Georgia, Alabama, and South Carolina

    USGS Publications Warehouse

    Williams, Lester J.; Dixon, Joann F.

    2015-01-01

    Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system were developed to define an updated hydrogeologic framework as part of the U.S. Geological Survey Groundwater Resources Program. The dataset contains structural surfaces depicting the top and base of the aquifer system, its major and minor hydrogeologic units and zones, geophysical marker horizons, and the altitude of the 10,000-milligram-per-liter total dissolved solids boundary that defines the approximate fresh and saline parts of the aquifer system. The thicknesses of selected major and minor units or zones were determined by interpolating points of known thickness or from raster surface subtraction of the structural surfaces. Additional data contained include clipping polygons; regional polygon features that represent geologic or hydrogeologic aspects of the aquifers and the minor units or zones; data points used in the interpolation; and polygon and line features that represent faults, boundaries, and other features in the aquifer system.

  12. Peptide-dependent Conformational Fluctuation Determines the Stability of the Human Leukocyte Antigen Class I Complex*

    PubMed Central

    Yanaka, Saeko; Ueno, Takamasa; Shi, Yi; Qi, Jianxun; Gao, George F.; Tsumoto, Kouhei; Sugase, Kenji

    2014-01-01

    In immune-mediated control of pathogens, human leukocyte antigen (HLA) class I presents various antigenic peptides to CD8+ T-cells. Long-lived peptide presentation is important for efficient antigen-specific T-cell activation. Presentation time depends on the peptide sequence and the stability of the peptide-HLA complex (pHLA). However, the determinant of peptide-dependent pHLA stability remains elusive. Here, to reveal the pHLA stabilization mechanism, we examined the crystal structures of an HLA class I allomorph in complex with HIV-derived peptides and evaluated site-specific conformational fluctuations using NMR. Although the crystal structures of various pHLAs were almost identical independent of the peptides, fluctuation analyses identified a peptide-dependent minor state that would be more tightly packed toward the peptide. The minor population correlated well with the thermostability and cell surface presentation of pHLA, indicating that this newly identified minor state is important for stabilizing the pHLA and facilitating T-cell recognition. PMID:25028510

  13. The Final Frontier - Transitions and Sustainability: From Mentored to Independent Research

    PubMed Central

    Zea, Maria Cecilia; Bowleg, Lisa

    2017-01-01

    A recurrent theme in much of the contemporary HIV behavioral and social science research is that ecological approaches that acknowledge the interplay of structural, institutional, and individual-level factors are essential to improve HIV prevention efforts in racial/ethnic minority communities. Similarly, an ecological approach provides an innovative framework for understanding the challenges that many racial/ethnic minority HIV prevention researchers face in their quest to transition from mentored researcher to independent researchers. Informed by an ecological framework, and building on our experiences as two racial/ethnic minority women HIV prevention researchers who transitioned from a formal research mentorship relationship to become independent HIV prevention researchers — principal investigators of NIH-funded R01 grants —, we frame our discussion of the mentored to independence research trajectory with a focus on structural, institutional, and individual determinants. Throughout, we integrate suggestions for how institutions, mentors, and HIV prevention researchers can facilitate the final frontier from mentored research to independence. PMID:27007125

  14. Parentification, substance use, and sex among adolescent daughters from ethnic minority families: the moderating role of monitoring.

    PubMed

    Sang, Jina; Cederbaum, Julie A; Hurlburt, Michael S

    2014-06-01

    Guided by structural family systems theory, this study explored the relationship between parentification and adolescent daughters' sexual risk engagement and substance use. We also explored how adolescent reports of parental monitoring moderated the relationship between parentification and adolescent risk. Data were from a cross-sectional, cross-generational study of 176 mother-daughter dyads from low-income, inner-city, ethnic minority families. In this sample, which included a subset of mothers with HIV, parental physical symptoms were associated with slightly higher levels of parentification. Parentification was associated with adolescent daughters' intention to have sex (but not substance use) in a direction opposite to prediction. Higher parentification was associated with lower intention to have sex. Parental monitoring did not moderate relationships between parentification and adolescent risk. These findings highlight that despite the negative influence hypothesized in structural family systems theory, parentification was not associated with risk engagement of high-risk adolescent daughters in ethnic minority families with low income. © 2013 FPI, Inc.

  15. Cross-ethnic generalizability of the three-factor model of psychopathy: the Youth Psychopathic Traits Inventory in an incarcerated sample of native Dutch and Moroccan immigrant boys.

    PubMed

    Veen, Violaine C; Stevens, Gonneke W J M; Andershed, Henrik; Raaijmakers, Quinten A W; Doreleijers, Theo A H; Vollebergh, Wilma A M

    2011-01-01

    Previous research provides support for the existence of the psychopathy construct in youths. However, studies regarding the psychometric properties of psychopathy measures with ethnic minority youths are lacking. In the present study, the three-factor structure of the Youth Psychopathic Traits Inventory (YPI) was examined for both native Dutch youth (N=158) and an ethnic minority group, Moroccans (N=141), in an incarcerated adolescent population in the Netherlands. Our results showed that the three-factor structure of the YPI is comparable across an ethnic majority and an ethnic minority group in an incarcerated sample in the Netherlands. Moreover, associations between psychopathic traits and mental health problems were similar for both ethnic groups. The results support the cross-ethnic generalizability of the three-factor model of psychopathy as measured through the Youth Psychopathic Traits Inventory. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Enhancing Diversity in Physics: The Fisk-Vanderbilt Masters-to-PhD Bridge Program

    NASA Astrophysics Data System (ADS)

    Stassun, Keivan

    2010-03-01

    We describe the Fisk-Vanderbilt Masters-to-PhD Bridge program as a model for partnering with minority-serving institutions to increase the representation of women and minorities earning PhDs in astronomy and related disciplines. Since its inception in 2004, the Fisk-Vanderbilt Bridge program has attracted 30 minority students, 60% of whom are female, and with a retention rate of 94%. When the first Bridge students completed their PhDs in 2010-11, the program will become the top awarder of astronomy PhDs to underrepresented minorities in the United States. Already, Fisk has become the top producer of physics Masters degrees to African Americans. We summarize the program's structure, approach, and research basis with the goal of providing a replicable model for other institutions seeking to build similar collaborative, research-based bridging partnerships.

  17. Action of an endo-β-1,3(4)-glucanase on cellobiosyl unit structure in barley β-1,3:1,4-glucan

    PubMed Central

    Kuge, Takao; Nagoya, Hiroki; Tryfona, Theodora; Kurokawa, Tsunemi; Yoshimi, Yoshihisa; Dohmae, Naoshi; Tsubaki, Kazufumi; Dupree, Paul; Tsumuraya, Yoichi; Kotake, Toshihisa

    2015-01-01

    β-1,3:1,4-Glucan is a major cell wall component accumulating in endosperm and young tissues in grasses. The mixed linkage glucan is a linear polysaccharide mainly consisting of cellotriosyl and cellotetraosyl units linked through single β-1,3-glucosidic linkages, but it also contains minor structures such as cellobiosyl units. In this study, we examined the action of an endo-β-1,3(4)-glucanase from Trichoderma sp. on a minor structure in barley β-1,3:1,4-glucan. To find the minor structure on which the endo-β-1,3(4)-glucanase acts, we prepared oligosaccharides from barley β-1,3:1,4-glucan by endo-β-1,4-glucanase digestion followed by purification by gel permeation and paper chromatography. The endo-β-1,3(4)-glucanase appeared to hydrolyze an oligosaccharide with degree of polymerization 5, designated C5-b. Based on matrix-assisted laser desorption/ionization (MALDI) time-of-flight (ToF)/ToF-mass spectrometry (MS)/MS analysis, C5-b was identified as β-Glc-1,3-β-Glc-1,4-β-Glc-1,3-β-Glc-1,4-Glc including a cellobiosyl unit. The results indicate that a type of endo-β-1,3(4)-glucanase acts on the cellobiosyl units of barley β-1,3:1,4-glucan in an endo-manner. PMID:26027730

  18. Perspectives on the Structure of American Agriculture. Volume I: The View from the Farm--Special Problems of Minority and Low-Income Farmers.

    ERIC Educational Resources Information Center

    Coughlin, Kenneth M., Ed.

    This is the first of two volumes of papers examining the impact of national agricultural policy on the rural poor. The seven articles in this volume offer personal accounts of minority and low-income farmers struggling to gain a foothold in American agriculture. "'It's Too Late for Our Family,'" by Marian Lenzen, describes a family's…

  19. The large-scale structure of the asteroid belt

    NASA Technical Reports Server (NTRS)

    Zellner, B.; Thirunagari, A.; Bender, D.

    1985-01-01

    The distributions of 2888 numbered minor planets over orbital inclination, eccentricity, and semimajor axis are examined, and 19 zones believed to adequately isolate the selection biases in survey programs of the physical properties of minor planets are defined. Six numbered asteroids have exceptional orbits and fall into no zone. Attention is called to rather sharp upper limits, which become increasingly stringent at larger heliocentric distances, on orbital inclinations and eccentricity.

  20. Optimization of the defects and the nonradiative lifetime of GaAs/AlGaAs double heterostructures

    NASA Astrophysics Data System (ADS)

    Cevher, Z.; Folkes, P. A.; Hier, H. S.; VanMil, B. L.; Connelly, B. C.; Beck, W. A.; Ren, Y. H.

    2018-04-01

    We used Raman scattering and time-resolved photoluminescence spectroscopy to investigate the molecular-beam-epitaxy (MBE) growth parameters that optimize the structural defects and therefore the internal radiative quantum efficiency of MBE-grown GaAs/AlGaAs double heterostructures (DH). The DH structures were grown at two different temperatures and three different As/Ga flux ratios to determine the conditions for an optimized structure with the longest nonradiative minority carrier lifetime. Raman scattering measurements show an improvement in the lattice disorder in the AlGaAs and GaAs layers as the As/Ga flux ratio is reduced from 40 to 15 and as the growth temperature is increased from 550 to 595 °C. The optimized structure is obtained with the As/Ga flux ratio equal to 15 and the substrate temperature 595 °C. This is consistent with the fact that the optimized structure has the longest minority carrier lifetime. Moreover, our Raman studies reveal that incorporation of a distributed Bragg reflector layer between the substrate and DH structures significantly reduces the defect density in the subsequent epitaxial layers.

  1. Minor groove RNA triplex in the crystal structure of a ribosomal frameshifting viral pseudoknot

    NASA Technical Reports Server (NTRS)

    Su, L.; Chen, L.; Egli, M.; Berger, J. M.; Rich, A.

    1999-01-01

    Many viruses regulate translation of polycistronic mRNA using a -1 ribosomal frameshift induced by an RNA pseudoknot. A pseudoknot has two stems that form a quasi-continuous helix and two connecting loops. A 1.6 A crystal structure of the beet western yellow virus (BWYV) pseudoknot reveals rotation and a bend at the junction of the two stems. A loop base is inserted in the major groove of one stem with quadruple-base interactions. The second loop forms a new minor-groove triplex motif with the other stem, involving 2'-OH and triple-base interactions, as well as sodium ion coordination. Overall, the number of hydrogen bonds stabilizing the tertiary interactions exceeds the number involved in Watson-Crick base pairs. This structure will aid mechanistic analyses of ribosomal frameshifting.

  2. Evolutionary dynamics and the phase structure of the minority game

    NASA Astrophysics Data System (ADS)

    Yuan, Baosheng; Chen, Kan

    2004-06-01

    We show that a simple evolutionary scheme, when applied to the minority game (MG), changes the phase structure of the game. In this scheme each agent evolves individually whenever his wealth reaches the specified bankruptcy level, in contrast to the evolutionary schemes used in the previous works. We show that evolution greatly suppresses herding behavior, and it leads to better overall performance of the agents. Similar to the standard nonevolutionary MG, the dependence of the standard deviation σ on the number of agents N and the memory length m can be characterized by a universal curve. We suggest a crowd-anticrowd theory for understanding the effect of evolution in the MG.

  3. Stigma and Minority Stress as Social Determinants of Health Among Lesbian, Gay, Bisexual, and Transgender Youth: Research Evidence and Clinical Implications.

    PubMed

    Hatzenbuehler, Mark L; Pachankis, John E

    2016-12-01

    In this article, we review theory and evidence on stigma and minority stress as social/structural determinants of health among lesbian, gay, bisexual, and transgender (LGBT) youth. We discuss different forms of stigma at individual (eg, identity concealment), interpersonal (eg, victimization), and structural (eg, laws and social norms) levels, as well as the mechanisms linking stigma to adverse health outcomes among LGBT youth. Finally, we discuss clinical (eg, cognitive behavioral therapy) and public health (eg, antibullying policies) interventions that effectively target stigma-inducing mechanisms to improve the health of LGBT youth. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Mixing Characteristics of Elliptical Jet Control with Crosswire

    NASA Astrophysics Data System (ADS)

    Manigandan, S.; Vijayaraja, K.

    2018-02-01

    The aerodynamic mixing efficiency of elliptical sonic jet flow with the effect of crosswire is studied computationally and experimentally at different range of nozzle pressure ratio with different orientation along the minor axis of the exit. The cross wire of different orientation is found to reduce the strength of the shock wave formation. Due to the presence of crosswire the pitot pressure oscillation is reduced fast, which weakens the shock cell structure. When the cross wire is placed at center position we see high mixing along the major axis. Similarly, when the cross wire is placed at ¼ and ¾ position we see high mixing promotion along minor axis. It also proves, as the position of the cross wire decreased along minor axis there will be increase in the mixing ratio. In addition to that we also found that, jet spread is high in major axis compared to minor axis due to bifurcation of jet along upstream

  5. Cultural variability in Expressed Emotion among families of adolescents with anorexia nervosa.

    PubMed

    Hoste, Renee Rienecke; Labuschagne, Zandre; Lock, James; Le Grange, Daniel

    2012-01-01

    To examine the cultural variability in Expressed Emotion (EE) among families of white and ethnic minority adolescents with anorexia nervosa (AN). One-hundred and eighty-nine AN patients and their parents completed the Eating Disorder Examination and the Structured Clinical Family Interview, from which EE ratings were made. No differences were found in the number of white and minority families classified as high EE. White families were higher on warmth (W) and tended to be higher on positive remarks (PR) than minority families. High EE was associated with a longer duration of illness, but was not related to eating disorder pathology. Few differences were found between white and ethnic minority families on the EE dimensions of CC, hostility (H), or EOI. Differences between families on W and PR, however, may have important treatment implications. Copyright © 2010 Wiley Periodicals, Inc.

  6. Human Development XIII: The Connection Between the Structure of the Overtone System and the Tone Language of Music. Some Implications for Our Understanding of the Human Brain

    PubMed Central

    Ventegodt, Søren; Hermansen, Tyge Dahl; Kandel, Isack; Merrick, Joav

    2008-01-01

    The functioning brain behaves like one highly-structured, coherent, informational field. It can be popularly described as a “coherent ball of energy”, making the idea of a local highly-structured quantum field that carries the consciousness very appealing. If that is so, the structure of the experience of music might be a quite unique window into a hidden quantum reality of the brain, and even of life itself. The structure of music is then a mirror of a much more complex, but similar, structure of the energetic field of the working brain. This paper discusses how the perception of music is organized in the human brain with respect to the known tone scales of major and minor. The patterns used by the brain seem to be similar to the overtones of vibrating matter, giving a positive experience of harmonies in major. However, we also like the minor scale, which can explain brain patterns as fractal-like, giving a symmetric “downward reflection” of the major scale into the minor scale. We analyze the implication of beautiful and ugly tones and harmonies for the model. We conclude that when it comes to simple perception of harmonies, the most simple is the most beautiful and the most complex is the most ugly, but in music, even the most disharmonic harmony can be beautiful, if experienced as a part of a dynamic release of musical tension. This can be taken as a general metaphor of painful, yet meaningful, and developing experiences in human life. PMID:18661052

  7. Cultural diversity and the mistreatment of older people in black and minority ethnic communities: some implications for service provision.

    PubMed

    Bowes, Alison; Avan, Ghizala; Macintosh, Sherry Bien

    2012-07-01

    Previous research on mistreatment of older people in black and minority ethnic communities has identified limited service responses and the need to consider mistreatment as an issue not only for individuals but also for families, communities, and institutions. The impact of cultural factors on understandings, experiences, and remedies for mistreatment has been debated. Drawing on empirical research in the United Kingdom involving service providers and ethnically-diverse community members, the article explores implications of cultural variation for service provision. Clear gaps exist between service provision and people experiencing mistreatment due to structural and contextual factors; cultural factors have a relatively minor impact.

  8. Inventory of college challenges for ethnic minority students: psychometric properties of a new instrument in Chinese Americans.

    PubMed

    Ying, Yu-Wen; Lee, Peter Allen; Tsai, Jeanne L

    2004-11-01

    The Inventory of College Challenges for Ethnic Minority Students (ICCEMS) is a newly developed instrument that assesses challenges faced by ethnic minority college students across a range of cultural, academic, social, and practical domains. The present study tested the ICCEMS among Chinese American students in an attempt to identify its factor structure and assess its psychometric properties. A total of 13 factor domains emerged. The Cronbach's alpha and 1-month test-retest reliability of the subscales and the overall scale supported their reliability. Both criterion and construct validities were also demonstrated. Chinese American college students faced the greatest challenges in terms of unclear career direction and academic demands. 2004 APA

  9. How criminal system racial disparities may translate into health disparities.

    PubMed

    Iguchi, Martin Y; Bell, James; Ramchand, Rajeev N; Fain, Terry

    2005-11-01

    Disadvantaged racial and ethnic minorities in the U.S. are strikingly over-represented in the juvenile justice and adult criminal justice systems. This paper briefly reviews the extent of over-representation attributable primarily to drug offenses and an earlier conceptual framework introduced by Iguchi and colleagues showing how the use of incarceration as a key drug control tool has disproportionately affected the health and well being of racial and ethnic minority communities. We then provide observations from the field that demonstrate how the implementation of a quality assessment approach might be used to mitigate procedural/structural biases that contribute to disparities in minority confinement, and ultimately, to reduce disparities in access to resources and health care.

  10. Anchistropus spp. (Crustacea: Cladocera: Chydoridae): a new distribution record for Lake Erie

    USGS Publications Warehouse

    Evans, Marlene S.; Hiltunen, Jarl K.; Schloesser, Donald W.

    1990-01-01

    This note extends the known Great Lakes distribution of Anchistropus sp. from Lake Michigan, Huron, Superior, and St. Clair to Rondeau Harbor in Lake Erie. Anchistropus sp. was collected in benthic samples where it occurred as epibionts on hydra. Previous studies, which are briefly reviewed, have noted the parasitic nature of Anchistropus. Although only one species of Anchistropus (A. minor) is known from North America, our specimens cannot be positively identified as that species: the structure of the postabdomen and first leg differs from the original taxonomic description of A. minor. Others have noted differences between the original description of A. minor and the morphology of specimens collected over the succeeding years.

  11. Theoretical analysis of nBn infrared photodetectors

    NASA Astrophysics Data System (ADS)

    Ting, David Z.; Soibel, Alexander; Khoshakhlagh, Arezou; Gunapala, Sarath D.

    2017-09-01

    The depletion and surface leakage dark current suppression properties of unipolar barrier device architectures such as the nBn have been highly beneficial for III-V semiconductor-based infrared detectors. Using a one-dimensional drift-diffusion model, we theoretically examine the effects of contact doping, minority carrier lifetime, and absorber doping on the dark current characteristics of nBn detectors to explore some basic aspects of their operation. We found that in a properly designed nBn detector with highly doped excluding contacts the minority carriers are extracted to nonequilibrium levels under reverse bias in the same manner as the high operating temperature (HOT) detector structure. Longer absorber Shockley-Read-Hall (SRH) lifetimes result in lower diffusion and depletion dark currents. Higher absorber doping can also lead to lower diffusion and depletion dark currents, but the benefit should be weighted against the possibility of reduced diffusion length due to shortened SRH lifetime. We also briefly examined nBn structures with unintended minority carrier blocking barriers due to excessive n-doping in the unipolar electron barrier, or due to a positive valence band offset between the barrier and the absorber. Both types of hole blocking structures lead to higher turn-on bias, although barrier n-doping could help suppress depletion dark current.

  12. Vortex dynamics and wall shear stress behaviour associated with an elliptic jet impinging upon a flat plate

    NASA Astrophysics Data System (ADS)

    Long, J.; New, T. H.

    2016-07-01

    Vortical structures and dynamics of a Re h = 2100 elliptic jet impinging upon a flat plate were studied at H/ d h = 1, 2 and 4 jet-to-plate separation distances. Flow investigations were conducted along both its major and minor planes using laser-induced fluorescence and digital particle image velocimetry techniques. Results show that the impingement process along the major plane largely consists of primary jet ring-vortex and wall-separated secondary vortex formations, where they subsequently separate from the flat plate at smaller H/ d h = 1 and 2 separation distances. Key vortex formation locations occur closer to the impingement point as the separation distance increases. Interestingly, braid vortices and rib structures begin to take part in the impingement process at H/ d h = 4 and wave instabilities dominate the flow field. In contrast, significantly more coherent primary and secondary vortices with physically larger vortex core sizes and higher vortex strengths are observed along the minor plane, with no signs of braid vortices and rib structures. Lastly, influences of these different flow dynamics on the major and minor plane instantaneous and mean skin friction coefficient levels are investigated to shed light on the effects of separation distance on the wall shear stress distributions.

  13. COPING AS A MEDIATOR OF INTERNALIZED HOMOPHOBIA AND PSYCHOLOGICAL DISTRESS AMONG YOUNG ADULT SEXUAL MINORITY WOMEN

    PubMed Central

    Kaysen, Debra; Kulesza, Magdalena; Balsam, Kimberly F.; Rhew, Isaac C.; Blayney, Jessica A.; Lehavot, Keren; Hughes, Tonda L.

    2014-01-01

    Sexual minorities have higher rates of depression and anxiety than their heterosexual counterparts. This elevated risk of psychological distress has generally been hypothesized to be a result of the effects of discrimination including internalized negative beliefs about sexual minorities. However, little research has examined the role of various types of coping in mediating between internalized homophobia and mental health. We tested the direct relationship between internalized homophobia and psychological distress and evaluated general and sexual minority-specific coping strategies as potential mediators using structural equation modeling. Data are from a national sample of 1,099 young adult sexual minority women who were on average 20.86 (SD= 2.12) years old, participating in a study on mental health and substance use. The model demonstrated acceptable fit, χ2 (83) = 402.9, p <.001, CFI=.94, TLI=.92, SRMR= .07, and RMSEA=.06, accounting for 73% of variance in psychological distress. Greater use of maladaptive coping and less use of sexual minority-specific coping were associated with higher psychological distress. Although maladaptive coping mediated the relationship between internalized homophobia and psychological distress, sexual minority-specific coping did not. Our findings support previous studies that have demonstrated the impact of internalized homophobia on psychological distress as well as the role of coping as a protective/risk factor in this relationship. PMID:25530980

  14. COPING AS A MEDIATOR OF INTERNALIZED HOMOPHOBIA AND PSYCHOLOGICAL DISTRESS AMONG YOUNG ADULT SEXUAL MINORITY WOMEN.

    PubMed

    Kaysen, Debra; Kulesza, Magdalena; Balsam, Kimberly F; Rhew, Isaac C; Blayney, Jessica A; Lehavot, Keren; Hughes, Tonda L

    2014-09-01

    Sexual minorities have higher rates of depression and anxiety than their heterosexual counterparts. This elevated risk of psychological distress has generally been hypothesized to be a result of the effects of discrimination including internalized negative beliefs about sexual minorities. However, little research has examined the role of various types of coping in mediating between internalized homophobia and mental health. We tested the direct relationship between internalized homophobia and psychological distress and evaluated general and sexual minority-specific coping strategies as potential mediators using structural equation modeling. Data are from a national sample of 1,099 young adult sexual minority women who were on average 20.86 ( SD = 2.12) years old, participating in a study on mental health and substance use. The model demonstrated acceptable fit, χ 2 (83) = 402.9, p <.001, CFI =.94, TLI =.92, SRMR = .07, and RMSEA =.06, accounting for 73% of variance in psychological distress. Greater use of maladaptive coping and less use of sexual minority-specific coping were associated with higher psychological distress. Although maladaptive coping mediated the relationship between internalized homophobia and psychological distress, sexual minority-specific coping did not. Our findings support previous studies that have demonstrated the impact of internalized homophobia on psychological distress as well as the role of coping as a protective/risk factor in this relationship.

  15. Testing a mediation framework for the link between perceived discrimination and psychological distress among sexual minority individuals.

    PubMed

    Liao, Kelly Yu-Hsin; Kashubeck-West, Susan; Weng, Chih-Yuan; Deitz, Cori

    2015-04-01

    Perceived discrimination is a risk factor for mental health problems among sexual minority individuals. An increasing number of research studies have investigated the mechanisms through which stigma-related stressors such as perceived discrimination are linked with adverse mental health outcomes for sexual minority populations. The integrative mediation framework proposed by Hatzenbuehler (2009) underscores the importance of identifying mediators in the association between stigma-related stressors and mental health outcomes. This study tested 3 mediators--expectations of rejection, anger rumination, and self-compassion--in the perceived discrimination-distress link. Moreover, it examined associations among these mediators. A nationwide sample of 265 sexual minorities responded to an online survey. Structural equation modeling results supported the mediator roles of expectations of rejection, anger rumination, and self-compassion. More specifically, perceived discrimination was associated with expectations of rejection, which, in turn, was associated with increased anger rumination and less self-compassion, resulting in greater psychological distress. The findings suggest several avenues for prevention and intervention with sexual minority individuals. (c) 2015 APA, all rights reserved).

  16. Lesbian, gay, & bisexual older adults: linking internal minority stressors, chronic health conditions, and depression.

    PubMed

    Hoy-Ellis, Charles P; Fredriksen-Goldsen, Karen I

    2016-11-01

    This study aims to: (1) test whether the minority stressors disclosure of sexual orientation; and (2) internalized heterosexism are predictive of chronic physical health conditions; and (3) depression; (4) to test direct and indirect relationships between these variables; and (5) whether chronic physical health conditions are further predictive of depression, net of disclosure of sexual orientation and internalized heterosexism. Secondary analysis of national, community-based surveys of 2349 lesbian, gay, and bisexual adults aged 50 and older residing in the US utilizing structural equation modeling. Congruent with minority stress theory, disclosure of sexual orientation is indirectly associated with chronic physical health conditions and depression, mediated by internalized heterosexism with a suppressor effect. Internalized heterosexism is directly associated with chronic physical health conditions and depression, and further indirectly associated with depression mediated by chronic physical health conditions. Finally, chronic physical health conditions have an additional direct relationship with depression, net of other predictor variables. Minority stressors and chronic physical health conditions independently and collectively predict depression, possibly a synergistic effect. Implications for depression among older sexual minority adults are discussed.

  17. The feasibility of accommodating physically handicapped individuals on pedestrian over and undercrossing structures. Appendix

    DOT National Transportation Integrated Search

    2008-09-01

    This report describes the evaluation of a sampling of over- and undercrossing structures to identify major and minor access barriers for the physically handicapped. From this evaluation, it was determined that it is feasible to accommodate the physic...

  18. Minor groove binding of a bis-quaternary ammonium compound: the crystal structure of SN 7167 bound to d(CGCGAATTCGCG)2.

    PubMed Central

    Squire, C J; Clark, G R; Denny, W A

    1997-01-01

    The X-ray crystal structure of the complex between the synthetic antitumour and antiviral DNA binding ligand SN 7167 and the DNA oligonucleotide d(CGCGAATTCGCG)2 has been determined to an R factor of 18.3% at 2.6 A resolution. The ligand is located within the minor groove and covers almost 6 bp with the 1-methylpyridinium ring extending as far as the C9-G16 base pair and the 1-methylquinolinium ring lying between the G4-C21 and A5-T20 base pairs. The ligand interacts only weakly with the DNA, as evidenced by long range contacts and shallow penetration into the groove. This structure is compared with that of the complex between the parent compound SN 6999 and the alkylated DNA sequence d(CGC[e6G]AATTCGCG)2. There are significant differences between the two structures in the extent of DNA bending, ligand conformation and groove binding. PMID:9321660

  19. CarD uses a minor groove wedge mechanism to stabilize the RNA polymerase open promoter complex.

    PubMed

    Bae, Brian; Chen, James; Davis, Elizabeth; Leon, Katherine; Darst, Seth A; Campbell, Elizabeth A

    2015-09-08

    A key point to regulate gene expression is at transcription initiation, and activators play a major role. CarD, an essential activator in Mycobacterium tuberculosis, is found in many bacteria, including Thermus species, but absent in Escherichia coli. To delineate the molecular mechanism of CarD, we determined crystal structures of Thermus transcription initiation complexes containing CarD. The structures show CarD interacts with the unique DNA topology presented by the upstream double-stranded/single-stranded DNA junction of the transcription bubble. We confirm that our structures correspond to functional activation complexes, and extend our understanding of the role of a conserved CarD Trp residue that serves as a minor groove wedge, preventing collapse of the transcription bubble to stabilize the transcription initiation complex. Unlike E. coli RNAP, many bacterial RNAPs form unstable promoter complexes, explaining the need for CarD.

  20. Self-consistent electronic structure of disordered Fe/sub 0. 65/Ni/sub 0. 35/

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, D.D.; Pinski, F.J.; Stocks, G.M.

    1985-04-15

    We present the results of the first ab initio calculation of the electronic structure of the disordered alloy Fe/sub 0.65/Ni/sub 0.35/. The calculation is based on the multiple-scattering coherent-potential approach (KKR-CPA) and is fully self-consistent and spin polarized. Magnetic effects are included within local-spin-density functional theory using the exchange-correlation function of Vosko--Wilk--Nusair. The most striking feature of the calculation is that electrons of different spins experience different degrees of disorder. The minority spin electrons see a very large disorder, whereas the majority spin electrons see little disorder. Consequently, the minority spin density of states is smooth compared to the verymore » structured majority spin density of states. This difference is due to a subtle balance between exchange splitting and charge neutrality.« less

  1. Self-consistent electronic structure of disordered Fe/sub 0/ /sub 65/Ni/sub 0/ /sub 35/

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, D.D.; Pinski, F.J.; Stocks, G.M.

    1984-01-01

    We present the results of the first ab-initio calculation of the electronic structure of a disordered Fe/sub 0/ /sub 65/Ni/sub 0/ /sub 35/ alloy. The calculation is based on the multiple-scattering coherent-potential approach (KKR-CPA) and is fully self-consistent and spin-polarized. Magnetic effects are included within local-spin-density functional theory using the exchange-correlation function of Vosko-Wilk-Nusair. The most striking feature of the calculation is that electrons of different spins experience different degrees of disorder. The minority spin electrons see a very large disorder; whereas, the majority spin electrons see little disorder. Consequently, the minority spin density of states is smooth compared tomore » the very structured majority spin density of states. This difference is due to a subtle balance between exchange-splitting and charge neutrality. 15 references, 2 figures.« less

  2. Functional specificity of a Hox protein mediated by the recognition of minor groove structure.

    PubMed

    Joshi, Rohit; Passner, Jonathan M; Rohs, Remo; Jain, Rinku; Sosinsky, Alona; Crickmore, Michael A; Jacob, Vinitha; Aggarwal, Aneel K; Honig, Barry; Mann, Richard S

    2007-11-02

    The recognition of specific DNA-binding sites by transcription factors is a critical yet poorly understood step in the control of gene expression. Members of the Hox family of transcription factors bind DNA by making nearly identical major groove contacts via the recognition helices of their homeodomains. In vivo specificity, however, often depends on extended and unstructured regions that link Hox homeodomains to a DNA-bound cofactor, Extradenticle (Exd). Using a combination of structure determination, computational analysis, and in vitro and in vivo assays, we show that Hox proteins recognize specific Hox-Exd binding sites via residues located in these extended regions that insert into the minor groove but only when presented with the correct DNA sequence. Our results suggest that these residues, which are conserved in a paralog-specific manner, confer specificity by recognizing a sequence-dependent DNA structure instead of directly reading a specific DNA sequence.

  3. Experimental study of the minority-carrier transport at the polysilicon-monosilicon interface

    NASA Astrophysics Data System (ADS)

    Neugroschel, A.; Arienzo, M.; Isaac, R. D.; Komem, Y.

    1985-04-01

    This paper presents the results of an experimental study designed to explore both qualitatively and quantitatively the mechanism of the improved current gain in bipolar transistors with polysilicon emitter contacts. Polysilicon contacts were deposited and heat treated at different conditions. The electrical properties were measured using p-n junction test structures that are much more sensitive to the contact properties than are bipolar transistors. A simple phenomenological model was used to correlate the structural properties with electrical measurements. Possible transport mechanisms are examined and estimates are made about upper bounds on transport parameters in the principal regions of the devices. The main conclusion of this study is that the minority-carrier transport in the polycrystalline silicon is dominated by a highly disordered layer at the polysilicon-monosilicon interface characterized by very low minority-carrier mobility. The effective recombination velocity at the n(+) polysilicon-n(+) monosilicon interface was found to be a strong function of fabrication conditions. The results indicate that the recombination velocity can be much smaller than 10,000 cm/s.

  4. Nonlinear absorption properties of AlGaAs/GaAs multiple quantum wells grown by metalorganic chemical vapor deposition

    NASA Technical Reports Server (NTRS)

    Lee, Hsing-Chung; Kost, A.; Kawase, M.; Hariz, A.; Dapkus, P. Daniel

    1988-01-01

    The nonlinear absorption properties of the excitonic resonances associated with multiple quantum wells (MQWs) in AlGaAs/GaAs grown by metalorganic chemical vapor deposition are reported. The dependence of the saturation properties on growth parameters, especially growth temperature, and the well width are described. The minimum measured saturation intensity for these materials is 250 W/sq cm, the lowest reported value to date. The low saturation intensities are the result of excellent minority carrier properties. A systematic study of minority carrier lifetimes in quantum wells are reported. Lifetimes range from 50-350 ns depending on growth temperature and well width. When corrected for lateral diffusion effects and the measured minority carrier lifetime, the saturation data suggest that saturation intensities as low as 2.3 W/sq cm can be achieved in this system. The first measurements of the dependence of the exciton area and the magnitude of the excitonic absorption on well width are prsented. The growth of MQW structures on transparent GaP substrates is demonstrated and the electroabsorption properties of these structures are reviewed.

  5. Hippocampus minor and man's place in nature: a case study in the social construction of neuroanatomy.

    PubMed

    Gross, C G

    1993-10-01

    In mid-19th century Britain the possibility of evolution and particularly the evolution of man from apes was vigorously contested. Among the leading antievolutionists was the celebrated anatomist and paleontologist Richard Owen and among the leading defenders of evolution was Thomas Henry Huxley. The central dispute between them on human evolution was whether or not man's brain was fundamentally unique in having a hippocampus minor (known today as the calcar avis), a posterior horn in the lateral ventricle, and a posterior lobe. The author considers the background of this controversy, the origin and fate of the term hippocampus minor, why this structure became central to the question of human evolution, and how Huxley used it to support both Darwinism and the political ascendancy of Darwinians. The use of ventricular structures to distinguish humans from other animals appears to reflect an importance given to the ventricles that stretches back to ancient Greek medicine. This account illustrates both the extraordinary persistence of ideas in biology and the role of the political and social matrix in the study of the brain.

  6. Insights into the structural and physicochemical properties of small granular starches from two hydrophyte duckweeds, Spirodela oligorrhiza and Lemna minor.

    PubMed

    Chen, Lei; Yu, Changjiang; Ma, Yubin; Xu, Hua; Wang, Shumin; Wang, Yu; Liu, Xingxun; Zhou, Gongke

    2016-11-29

    The structure and physicochemical properties of starches from two hydrophyte duckweeds, Spirodela oligorrhiza and Lemna minor, were investigated and compared in this study. The amylose content and average size of starches were determined to be 20.85%, 4.70 μm and 27.77%, 6.17 μm for Spirodela oligorrhiza and Lemna minor, respectively. The average chain length of two duckweed starches was measured to be around DP 28. The chain length distribution was observed to be greatly different from other reported starches for the high proportion of long chains (DP ≥ 37) over 50%. Wide-angle X-ray diffraction profiles of the two starch samples displayed typical B-type diffraction pattern. The gelatinization enthalpy-changes (ΔH gel ) of two starch samples was about 10.40 J/g for two duckweed starches. The present results suggested the potential utilization of small granular starches from duckweed in functional foods and dietary supplement products. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Factors influencing health care access perceptions and care-seeking behaviors of immigrant Latino sexual minority men and transgender individuals: baseline findings from the HOLA intervention study.

    PubMed

    Tanner, Amanda E; Reboussin, Beth A; Mann, Lilli; Ma, Alice; Song, Eunyoung; Alonzo, Jorge; Rhodes, Scott D

    2014-11-01

    Little is known about immigrant Latino sexual minorities’ health seeking behaviors. This study examined factors associated with perceptions of access and actual care behaviors among this population in North Carolina. A community-based participatory research partnership recruited 180 Latino sexual minority men and transgender individuals within preexisting social networks to participate in a sexual health intervention. Mixed-effects logistic regression models and GIS mapping examined factors influencing health care access perceptions and use of services (HIV testing and routine check-ups). Results indicate that perceptions of access and actual care behaviors are low and affected by individual and structural factors, including: years living in NC, reported poor general health, perceptions of discrimination, micro-, meso-, and macro-level barriers, and residence in a Medically Underserved Area. To improve Latino sexual minority health, focus must be placed on multiple levels, including: individual characteristics (e.g., demographics), clinic factors (e.g., provider competence and clinic environment), and structural factors (e.g., discrimination).

  8. Minor Allele Frequency Changes the Nature of Genotype by Environment Interactions.

    PubMed

    Verhulst, Brad; Neale, Michael C

    2016-09-01

    In the classical twin study, phenotypic variation is often partitioned into additive genetic (A), common (C) and specific environment (E) components. From genetical theory, the outcome of genotype by environment interaction is expected to inflate A when the interacting factor is shared (i.e., C) between the members of a twin pair. We show that estimates of both A and C can be inflated. When the shared interacting factor changes the size of the difference between homozygotes' means, the expected sibling or DZ twin correlation is .5 if and only if the minor allele frequency (MAF) is .5; otherwise the expected DZ correlation is greater than this value, consistent (and confounded) with some additional effect of C. This result is considered in the light of the distribution of minor allele frequencies for polygenic traits. Also discussed is whether such interactions take place at the locus level or affect an aggregated biological structure or system. Interactions with structures or endophenotypes that result from the aggregated effects of many loci will generally emerge as part of the A estimate.

  9. 49 CFR 238.415 - Rollover strength.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... side frame. The allowable stress in the structural members of the occupied volumes for this condition shall be one-half yield or one-half the critical buckling stress, whichever is less. Minor localized... framing. The allowable stress in the structural members of the occupied volumes for this condition shall...

  10. Unusual hydrogen bonding patterns in AF (aminofluorene) and AAF (acetylaminofluorene) modified DNA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Broyde, S.; Hingerty, B.E.; Shapiro, R.

    1989-01-01

    New structures are presented for AF and AAF modified DNAs that place the carcinogen in the minor groove of a B-DNA helix. These structures employ non-Watson-Crick base pairing schemes with syn guanine at the modification site. 32 refs., 9 figs.

  11. 49 CFR 238.415 - Rollover strength.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... side frame. The allowable stress in the structural members of the occupied volumes for this condition shall be one-half yield or one-half the critical buckling stress, whichever is less. Minor localized... framing. The allowable stress in the structural members of the occupied volumes for this condition shall...

  12. 49 CFR 238.415 - Rollover strength.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... side frame. The allowable stress in the structural members of the occupied volumes for this condition shall be one-half yield or one-half the critical buckling stress, whichever is less. Minor localized... framing. The allowable stress in the structural members of the occupied volumes for this condition shall...

  13. 49 CFR 238.415 - Rollover strength.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... side frame. The allowable stress in the structural members of the occupied volumes for this condition shall be one-half yield or one-half the critical buckling stress, whichever is less. Minor localized... framing. The allowable stress in the structural members of the occupied volumes for this condition shall...

  14. 49 CFR 238.415 - Rollover strength.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... side frame. The allowable stress in the structural members of the occupied volumes for this condition shall be one-half yield or one-half the critical buckling stress, whichever is less. Minor localized... framing. The allowable stress in the structural members of the occupied volumes for this condition shall...

  15. The unusual gamma-ray burst GRB 101225A explained as a minor body falling onto a neutron star.

    PubMed

    Campana, S; Lodato, G; D'Avanzo, P; Panagia, N; Rossi, E M; Della Valle, M; Tagliaferri, G; Antonelli, L A; Covino, S; Ghirlanda, G; Ghisellini, G; Melandri, A; Pian, E; Salvaterra, R; Cusumano, G; D'Elia, V; Fugazza, D; Palazzi, E; Sbarufatti, B; Vergani, S D

    2011-11-30

    The tidal disruption of a solar-mass star around a supermassive black hole has been extensively studied analytically and numerically. In these events, the star develops into an elongated banana-shaped structure. After completing an eccentric orbit, the bound debris falls into the black hole, forming an accretion disk and emitting radiation. The same process may occur on planetary scales if a minor body passes too close to its star. In the Solar System, comets fall directly into our Sun or onto planets. If the star is a compact object, the minor body can become tidally disrupted. Indeed, one of the first mechanisms invoked to produce strong gamma-ray emission involved accretion of comets onto neutron stars in our Galaxy. Here we report that the peculiarities of the 'Christmas' gamma-ray burst (GRB 101225A) can be explained by a tidal disruption event of a minor body around an isolated Galactic neutron star. This would indicate either that minor bodies can be captured by compact stellar remnants more frequently than occurs in the Solar System or that minor-body formation is relatively easy around millisecond radio pulsars. A peculiar supernova associated with a gamma-ray burst provides an alternative explanation.

  16. Characterisation of case depth in induction-hardened medium carbon steels based on magnetic minor hysteresis loop measurement technique

    NASA Astrophysics Data System (ADS)

    He, Cunfu; Yang, Meng; Liu, Xiucheng; Wang, Xueqian; Wu, Bin

    2017-11-01

    The magnetic hysteresis behaviours of ferromagnetic materials vary with the heat treatment-induced micro-structural changes. In the study, the minor hysteresis loop measurement technique was used to quantitatively characterise the case depth in two types of medium carbon steels. Firstly, high-frequency induction quenching was applied in rod samples to increase the volume fraction of hard martensite to the soft ferrite/pearlite (or sorbite) in the sample surface. In order to determine the effective and total case depth, a complementary error function was employed to fit the measured hardness-depth profiles of induction-hardened samples. The cluster of minor hysteresis loops together with the tangential magnetic field (TMF) were recorded from all the samples and the comparative study was conducted among three kinds of magnetic parameters, which were sensitive to the variation of case depth. Compared to the parameters extracted from an individual minor loop and the distortion factor of the TMF, the magnitude of three-order harmonic of TMF was more suitable to indicate the variation in case depth. Two new minor-loop coefficients were introduced by combining two magnetic parameters with cumulative statistics of the cluster of minor-loops. The experimental results showed that the two coefficients monotonically linearly varied with the case depth within the carefully selected magnetisation region.

  17. Quenched Magnon excitations by oxygen sublattice reconstruction in (SrCuO2)n/(SrTiO3)2 superlattices.

    PubMed

    Dantz, M; Pelliciari, J; Samal, D; Bisogni, V; Huang, Y; Olalde-Velasco, P; Strocov, V N; Koster, G; Schmitt, T

    2016-09-12

    The recently discovered structural reconstruction in the cuprate superlattice (SrCuO2)n/(SrTiO3)2 has been investigated across the critical value of n = 5 using resonant inelastic x-ray scattering (RIXS). We find that at the critical value of n, the cuprate layer remains largely in the bulk-like two-dimensional structure with a minority of Cu plaquettes being reconstructed. The partial reconstruction leads to quenching of the magnons starting at the Γ-point due to the minority plaquettes acting as scattering points. Although comparable in relative abundance, the doped charge impurities in electron-doped cuprate superconductors do not show this quenching of magnetic excitations.

  18. Enhancement of minority carrier injection in ambipolar carbon nanotube transistors using double-gate structures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Bongjun; Liang, Kelly; Dodabalapur, Ananth, E-mail: ananth.dodabalapur@engr.utexas.edu

    We show that double-gate ambipolar thin-film transistors can be operated to enhance minority carrier injection. The two gate potentials need to be significantly different for enhanced injection to be observed. This enhancement is highly beneficial in devices such as light-emitting transistors where balanced electron and hole injections lead to optimal performance. With ambipolar single-walled carbon nanotube semiconductors, we demonstrate that higher ambipolar currents are attained at lower source-drain voltages, which is desired for portable electronic applications, by employing double-gate structures. In addition, when the two gates are held at the same potential, the expected advantages of the double-gate transistors suchmore » as enhanced on-current are also observed.« less

  19. Nonequilibrium Conditions Explain Spatial Variability in Genetic Structuring of Little Penguin (Eudyptula minor)

    PubMed Central

    Peucker, Amanda J.; Valautham, Sureen K.; Styan, Craig A.; Dann, Peter

    2015-01-01

    Factors responsible for spatial structuring of population genetic variation are varied, and in many instances there may be no obvious explanations for genetic structuring observed, or those invoked may reflect spurious correlations. A study of little penguins (Eudyptula minor) in southeast Australia documented low spatial structuring of genetic variation with the exception of colonies at the western limit of sampling, and this distinction was attributed to an intervening oceanographic feature (Bonney Upwelling), differences in breeding phenology, or sea level change. Here, we conducted sampling across the entire Australian range, employing additional markers (12 microsatellites and mitochondrial DNA, 697 individuals, 17 colonies). The zone of elevated genetic structuring previously observed actually represents the eastern half of a genetic cline, within which structuring exists over much shorter spatial scales than elsewhere. Colonies separated by as little as 27 km in the zone are genetically distinguishable, while outside the zone, homogeneity cannot be rejected at scales of up to 1400 km. Given a lack of additional physical or environmental barriers to gene flow, the zone of elevated genetic structuring may reflect secondary contact of lineages (with or without selection against interbreeding), or recent colonization and expansion from this region. This study highlights the importance of sampling scale to reveal the cause of genetic structuring. PMID:25833231

  20. Power, Identity, and Organizational Structure as Reflected in Schools for Minority Groups: A Case Study of Jewish Schools in Paris, Brussels, and Geneva

    ERIC Educational Resources Information Center

    Gross, Zehavit

    2006-01-01

    This article compares the linkages between organizational structure, power relations, and group identities within the private schools operated by the francophone Jewish communities of Brussels, Paris, and Geneva. A school's organizational structure and balance of power reflect its identity and its conceptual world. That is, its organizational…

  1. Accommodation of an N-(deoxyguanosin-8-yl)-2-acetylaminofluorene adduct in the active site of human DNA polymerase ι: Hoogsteen or Watson-Crick base pairing?†

    PubMed Central

    Donny-Clark, Kerry; Shapiro, Robert; Broyde, Suse

    2009-01-01

    Bypass across DNA lesions by specialized polymerases is essential for maintenance of genomic stability. Human DNA polymerase ι (polι) is a bypass polymerase of the Y family. Crystal structures of polι suggest that Hoogsteen base pairing is employed to bypass minor groove DNA lesions, placing them on the spacious major groove side of the enzyme. Primer extension studies have shown that polι is also capable of error-free nucleotide incorporation opposite the bulky major groove adduct N-(deoxyguanosin-8-yl)-2-acetyl-aminofluorene (dG-AAF). We present molecular dynamics simulations and free energy calculations suggesting that Watson-Crick base pairing could be employed in polι for bypass of dG-AAF. In polι with Hoogsteen paired dG-AAF the bulky AAF moiety would reside on the cramped minor groove side of the template. The Hoogsteen-capable conformation distorts the active site, disrupting interactions necessary for error-free incorporation of dC opposite the lesion. Watson-Crick pairing places the AAF rings on the spacious major groove side, similar to the position of minor groove adducts observed with Hoogsteen pairing. Watson-Crick paired structures show a well-ordered active site, with a near reaction-ready ternary complex. Thus our results suggest that polι would utilize the same spacious region for lesion bypass of both major and minor groove adducts. Therefore, purine adducts with bulk on the minor groove side would use Hoogsteen pairing, while adducts with the bulky lesion on the major groove side would utilize Watson-Crick base pairing as indicated by our MD simulations for dG-AAF. This suggests the possibility of an expanded role for polι in lesion bypass. PMID:19072536

  2. Accommodation of an N-(deoxyguanosin-8-yl)-2-acetylaminofluorene adduct in the active site of human DNA polymerase iota: Hoogsteen or Watson-Crick base pairing?

    PubMed

    Donny-Clark, Kerry; Shapiro, Robert; Broyde, Suse

    2009-01-13

    Bypass across DNA lesions by specialized polymerases is essential for maintenance of genomic stability. Human DNA polymerase iota (poliota) is a bypass polymerase of the Y family. Crystal structures of poliota suggest that Hoogsteen base pairing is employed to bypass minor groove DNA lesions, placing them on the spacious major groove side of the enzyme. Primer extension studies have shown that poliota is also capable of error-free nucleotide incorporation opposite the bulky major groove adduct N-(deoxyguanosin-8-yl)-2-acetylaminofluorene (dG-AAF). We present molecular dynamics simulations and free energy calculations suggesting that Watson-Crick base pairing could be employed in poliota for bypass of dG-AAF. In poliota with Hoogsteen-paired dG-AAF the bulky AAF moiety would reside on the cramped minor groove side of the template. The Hoogsteen-capable conformation distorts the active site, disrupting interactions necessary for error-free incorporation of dC opposite the lesion. Watson-Crick pairing places the AAF rings on the spacious major groove side, similar to the position of minor groove adducts observed with Hoogsteen pairing. Watson-Crick-paired structures show a well-ordered active site, with a near reaction-ready ternary complex. Thus our results suggest that poliota would utilize the same spacious region for lesion bypass of both major and minor groove adducts. Therefore, purine adducts with bulk on the minor groove side would use Hoogsteen pairing, while adducts with the bulky lesion on the major groove side would utilize Watson-Crick base pairing as indicated by our MD simulations for dG-AAF. This suggests the possibility of an expanded role for poliota in lesion bypass.

  3. Approach to prevention of obesity of Roma population in the Region of South Bohemia with focus on selected eating behaviors.

    PubMed

    Dolák, František; Šedová, Lenka; Nováková, Dita; Olišarová, Věra

    2016-12-01

    To survey obesity prevention methods for use in the Roma population with a focus on eating behaviors. A semi-structured interview was used to identify potentially useful obesity prevention methods. Basic anthropometric measurements were also gathered at the same time. This study was part of the "Obesity and overweight in the Roma minority in the Region of South Bohemia" research project (grant project 280-COST-LD14114). Participants consisted of members of the Roma minority (302 respondents) as well as the majority (Czech) population for comparisons. Differences in eating behaviors like irregular eating schedules and excessive consumption of fast food were observed. Statistically significant differences between the Roma minority and the majority (Czech/non-Roma) population were found in this area with the help of statistical significance tests. The Chi-square characteristic of independence (χ2) was, in case of this distribution, valued at 30.815 with 5 degrees of freedom, P < 0.001. The analyses, based on the second degree of classification, identified statistically significant differences between the Roma minority and the majority population. Members of the Roma minority attended preventive health check-ups statistically less often than members of the majority population. Differences between the majority and the Roma population were also found in the degree of patient cooperation with general practitioners. The results show that the Roma population is more likely to engage in eating behaviors that can contribute to overweight and obesity than the majority population. Based on the results of a semi-structured interview and on the results of anthropometric measurements, we can say that the Roma population is at a greater health risk, relative to overweight and obesity, than the majority population.

  4. Intrinsic crystal phase separation in the antiferromagnetic superconductor Rb(y)Fe(2-x)Se2: a diffraction study.

    PubMed

    Yu Pomjakushin, V; Krzton-Maziopa, A; Pomjakushina, E V; Conder, K; Chernyshov, D; Svitlyk, V; Bosak, A

    2012-10-31

    The crystal and magnetic structures of the superconducting iron-based chalcogenides Rb(y)Fe(2-x)Se(2) have been studied by means of single-crystal synchrotron x-ray and high-resolution neutron powder diffraction in the temperature range 2-570 K. The ground state of the crystal is an intrinsically phase-separated state with two distinct-by-symmetry phases. The main phase has the iron vacancy ordered √5 × √5 superstructure (I4/m space group) with AFM ordered Fe spins. The minority phase does not have √5 × √5-type of ordering and has a smaller in-plane lattice constant a and larger tetragonal c-axis and can be well described by assuming the parent average vacancy disordered structure (I4/mmm space group) with the refined stoichiometry Rb(0.60(5))(Fe(1.10(5))Se)(2). The minority phase amounts to 8-10% mass fraction. The unit cell volume of the minority phase is 3.2% smaller than the one of the main phase at T = 2 K and has quite different temperature dependence. The minority phase merges with the main vacancy ordered phase on heating above the phase separation temperature T(P) = 475 K. The spatial dimensions of the phase domains strongly increase above T(P) from 1000 to >2500 Å due to the integration of the regions of the main phase that were separated by the second phase at low temperatures. Additional annealing of the crystals at a temperature T = 488 K, close to T(P), for a long time drastically reduces the amount of the minority phase.

  5. 36 CFR 18.12 - What specific provisions must a lease contain?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... extent authorized by the Federal Torts Claim Act or as otherwise expressly authorized by law; (g... construct new buildings or structures on leased property, provided that, a lease may contain appropriate..., minor additions, buildings and/or structures determined by the Director to be necessary for support of...

  6. A Review of Culturally Targeted/Tailored Tobacco Prevention and Cessation Interventions for Minority Adolescents

    PubMed Central

    Singh, Nisha; Krishnan-Sarin, Suchitra

    2012-01-01

    Aim: Emerging racial/ethnic disparities in tobacco use behaviors and resulting long-term health outcomes highlight the importance of developing culturally tailored/targeted tobacco prevention and cessation interventions. This manuscript describes the efficacy and the components of prevention and cessation interventions developed for minority adolescents. Methods: Thirteen studies focused on culturally tailoring and targeting tobacco prevention/cessation interventions were selected and information on intervention design (type, number of sessions), setting (school or community), theoretical constructs, culture-specific components (surface/deep structures), and treatment outcomes were extracted. Results: Of the 13 studies, 5 focused on prevention, 4 on cessation, and 4 combined prevention and cessation, and most of the studies were primarily school-based, while a few used community locations. Although diverse minority groups were targeted, a majority of the studies (n = 6) worked with Hispanic adolescents. The most common theoretical construct examined was the Social Influence Model (n = 5). The overall findings indicated that culturally tailoring cessation interventions did not appear to improve tobacco quit rates among minority adolescents, but culturally tailored prevention interventions appeared to produce lower tobacco initiation rates among minority adolescents than control conditions. Conclusions: The results of review suggest that there is a critical need to develop better interventions to reduce tobacco use among minority adolescents and that developing a better understanding of cultural issues related to both cessation and initiation of tobacco use among minority populations is a key component of this endeavor. PMID:22614548

  7. Reconnaissance and recovery of the brighter asteroids. Brief summary of the entire project

    NASA Technical Reports Server (NTRS)

    Edmonson, F. K.; Wood, H. J.

    1982-01-01

    An inexpensive method of baking large (8- by 10-inch) IIIa-J plates in 2 percent forming gas was found and successfully tested. The large storage capacity and fine grain structure of the emulsion made the sky fog negligible on plates of one-hour exposure at Link. Plates were taken through the end of October 18, 1981 on various asteroids from the recent critical lists published in the Minor Planet Circulars and the Russian Ephemeris of Minor Planets.

  8. DNA triplex structure, thermodynamics, and destabilisation: insight from molecular simulations.

    PubMed

    Boehm, Belinda J; Whidborne, Charles; Button, Alexander L; Pukala, Tara L; Huang, David M

    2018-05-23

    Molecular dynamics simulations are used to elucidate the structure and thermodynamics of DNA triplexes associated with the neurodegenerative disease Friedreich's ataxia (FRDA), as well as complexes of these triplexes with the small molecule netropsin, which is known to destabilise triplexes. The ability of molecular simulations in explicit solvent to accurately capture triplex thermodynamics is verified for the first time, with the free energy to dissociate a 15-base antiparallel purine triplex-forming oligomer (TFO) from the duplex found to be slightly higher than reported experimentally. The presence of netropsin in the minor groove destabilises the triplex as expected, reducing the dissociation free energy by approximately 50%. Netropsin binding is associated with localised narrowing of the minor groove near netropsin, an effect that has previously been under contention. This leads to localised widening of the major groove, weakening hydrogen bonds between the TFO and duplex. Consequently, destabilisation is found to be highly localised, occurring only when netropsin is bound directly opposite the TFO. The simulations also suggest that near saturation of the minor groove with ligand is required for complete triplex dissociation. A structural analysis of the DNA triplexes that can form with the FRDA-related duplex sequence indicates that the triplex with a parallel homopyrimidine TFO is likely to be more stable than the antiparallel homopurine-TFO triplex, which may have implications for disease onset and treatment.

  9. Race and Gender Differences in Undergraduate Research Mentoring Structures and Research Outcomes

    PubMed Central

    Aikens, Melissa L.; Robertson, Melissa M.; Sadselia, Sona; Watkins, Keiana; Evans, Mara; Runyon, Christopher R.; Eby, Lillian T.; Dolan, Erin L.

    2017-01-01

    Participating in undergraduate research with mentorship from faculty may be particularly important for ensuring the persistence of women and minority students in science. Yet many life science undergraduates at research universities are mentored by graduate or postdoctoral researchers (i.e., postgraduates). We surveyed a national sample of undergraduate life science researchers about the mentoring structure of their research experiences and the outcomes they realized from participating in research. We observed two common mentoring structures: an open triad with undergraduate–postgraduate and postgraduate–faculty ties but no undergraduate–faculty tie, and a closed triad with ties among all three members. We found that men and underrepresented minority (URM) students are significantly more likely to report a direct tie to their faculty mentors (closed triad) than women, white, and Asian students. We also determined that mentoring structure was associated with differences in student outcomes. Women’s mentoring structures were associated with their lower scientific identity, lower intentions to pursue a science, technology, engineering, and mathematics (STEM) PhD, and lower scholarly productivity. URM students’ mentoring structures were associated with higher scientific identity, greater intentions to pursue a STEM PhD, and higher scholarly productivity. Asian students reported lower scientific identity and intentions to pursue a STEM PhD, which were unrelated to their mentoring structures. PMID:28550078

  10. Ethnic density as a buffer for psychotic experiences: findings from a national survey (EMPIRIC).

    PubMed

    Das-Munshi, Jayati; Bécares, Laia; Boydell, Jane E; Dewey, Michael E; Morgan, Craig; Stansfeld, Stephen A; Prince, Martin J

    2012-10-01

    Aetiological mechanisms underlying ethnic density associations with psychosis remain unclear. To assess potential mechanisms underlying the observation that minority ethnic groups experience an increased risk of psychosis when living in neighbourhoods of lower own-group density. Multilevel analysis of nationally representative community-level data (from the Ethnic Minorities Psychiatric Illness Rates in the Community survey), which included the main minority ethnic groups living in England, and a White British group. Structured instruments assessed discrimination, chronic strains and social support. The Psychosis Screening Questionnaire ascertained psychotic experiences. For every ten percentage point reduction in own-group density, the relative odds of reporting psychotic experiences increased 1.07 times (95% CI 1.01-1.14, P = 0.03 (trend)) for the total minority ethnic sample. In general, people living in areas of lower own-group density experienced greater social adversity that was in turn associated with reporting psychotic experiences. People resident in neighbourhoods of higher own-group density experience 'buffering' effects from the social risk factors for psychosis.

  11. Assessing posterior ocular structures in β-thalassemia minor.

    PubMed

    Arifoglu, Hasan Basri; Kucuk, Bekir; Duru, Necati; Altunel, Orhan; Gulhan, Ahmet; Ozen, Mustafa; Aygun, Bilal; Atas, Mustafa

    2018-02-01

    The aim of this study was to investigate the effect of β-thalassemia minor on choroidal, macular, and peripapillary retinal nerve fiber layer thickness. To form the sample, we recruited 40 patients with β-thalassemia minor and 44 healthy participants. We used spectral-domain optical coherence tomography to take all measurements of ocular thickness, as well as measured intraocular pressure, axial length, and central corneal thickness. We later analyzed correlations of hemoglobin levels with ocular parameters. A statistically significant difference emerged between patients with β-thalassemia minor and the healthy controls in terms of mean values of subfoveal, nasal, and temporal choroidal thickness (p = 0.001, p = 0.016, and p = 0.010, respectively). Except for central macular thickness, differences in paracentral macular thicknesses between the groups were also significant (superior: p < 0.001, inferior: p = 0.007, temporal: p = 0.001, and nasal: p = 0.005). Also, no statistically significant differences were noted for retinal nerve fiber layer thickness between two groups. Mean values of subfoveal, nasal, temporal choroidal, and macular thickness for the four quadrants were significantly lower in patients with β-thalassemia minor than in healthy controls.

  12. Internalized Homophobia as a Partial Mediator between Homophobic Bullying and Self-Esteem among Sexual Minority Youths in Quebec (Canada)

    PubMed Central

    Blais, Martin; Gervais, Jesse; Hébert, Martine

    2016-01-01

    Verbal/psychological homophobic bullying is widespread among sexual minority youths. Homophobic bullying has been associated with both high internalized homophobia and low self-esteem. The objectives were to document verbal/psychological homophobic bullying among sexual minority youths and to model the relationships between homophobic bullying, internalized homophobia and self-esteem. Method: A community sample of 300 sexual minority youths aged 14 to 22 years old was used. A structural equations model was tested using a nonlinear, robust estimator implemented in Mplus. The model postulated that homophobic bullying impacts self-esteem both directly and indirectly, via internalized homophobia. Results: 60.7% of the sample reported at least on form of verbal/psychological homophobic bullying. The model explained 29% of the variance of self-esteem, 19.6% of the variance of internalized homophobia and 5.3% of the verbal/psychological homophobic bullying. The model suggests that the relationship between verbal/psychological homophobic bullying and self-esteem is partially mediated by internalized homophobia. Conclusion: Our results underscore the importance of initiatives to prevent homophobic bullying in order to prevent its negative effects on well-being of sexual minority youths. PMID:24714888

  13. The Stability of Intimate Partner Violence Perpetration From Adolescence to Emerging Adulthood in Sexual Minorities.

    PubMed

    Shorey, Ryan C; Fite, Paula J; Cohen, Joseph R; Stuart, Gregory L; Temple, Jeff R

    2018-06-01

    The objective of this study was to examine the stability of physical and sexual intimate partner violence (IPV) perpetration from adolescence to emerging adulthood among sexual minorities. Adolescents who identified as a sexual minority (N = 135; 71.1% female; mean age = 15.02, standard deviation=.77; 34.1% African-American/black, 26.7% white, 22.2% Hispanic) from southeast Texas were assessed annually for 6 years on their IPV perpetration. Structural equation modeling demonstrated that physical IPV perpetration was modestly stable across years 1-4 (24.6%, 24.6%, 26.4%, and 21.6%, respectively), decreased in year 5 (18.6%), and increased in year 6 (24.5%). The stability of sexual IPV perpetration was high across all 6 years (14.3%, 13%, 14.9%, 10.8%, 12.4%, and 14.4%). This is the first study to examine the stability of IPV perpetration among sexual minority adolescents. Findings suggest that the development of interventions for IPV among sexual minority adolescents is needed, as IPV is unlikely to desist from adolescence to emerging adulthood. Copyright © 2017 The Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  14. Asthma patient education opportunities in predominantly minority urban communities.

    PubMed

    Zayas, Luis E; McLean, Don

    2007-12-01

    Disenfranchised ethnic minority communities in the urban United States experience a high burden of asthma. Conventional office-based patient education often is insufficient to promote proper asthma management and coping practices responsive to minority patients' environments. This paper explores existing and alternative asthma information and education sources in three urban minority communities in western New York State to help design other practical educational interventions. Four focus groups (n = 59) and four town hall meetings (n = 109) were conducted in one Hispanic and two black communities. Focus groups included adult asthmatics or caretakers of asthmatics, and town meetings were open to all residents. A critical theory perspective informed the study. Asthma information and education sources, perceptions of asthma and ways of coping were elicited through semi-structured interviews. Data analysis followed a theory-driven immersion-crystallization approach. Several asthma education and information resources from the health care system, media, public institutions and communities were identified. Intervention recommendations highlighted asthma workshops that recognize participants as teachers and learners, offer social support, promote advocacy, are culturally appropriate and community-based and include health care professionals. Community-based, group health education couched on people's experiences and societal conditions offers unique opportunities for patient asthma care empowerment in minority urban communities.

  15. Internalized homophobia as a partial mediator between homophobic bullying and self-esteem among youths of sexual minorities in Quebec (Canada).

    PubMed

    Blais, Martin; Gervais, Jesse; Hébert, Martine

    2014-03-01

    Verbal/psychological homophobic bullying is widespread among youths of sexual minorities. Homophobic bullying has been associated with both high internalized homophobia and low self-esteem. The objectives were to document verbal/psychological homophobic bullying among youths of sexual minorities and model the relationships between homophobic bullying, internalized homophobia and self-esteem. A community sample of 300 youths of sexual minorities aged 14 to 22 years old was used. A structural equation model was tested using a nonlinear, robust estimator implemented in Mplus. The model postulated that homophobic bullying impacts self-esteem both directly and indirectly, via internalized homophobia. 60.7% of the sample reported at least one form of verbal/psychological homophobic bullying. The model explained 29% of the variance of self-esteem, 19.6% of the variance of internalized homophobia and 5.3% of the verbal/psychological homophobic bullying. The model suggests that the relationship between verbal/psychological homophobic bullying and self-esteem is partially mediated by internalized homophobia. The results underscore the importance of initiatives to prevent homophobic bullying in order to prevent its negative effects on the well-being of youths of sexual minorities.

  16. Challenges and dilemmas: fieldwork with upland minorities in socialist Vietnam, Laos and southwest China.

    PubMed

    Turner, Sarah

    2010-01-01

    The Chinese, Vietnamese and Lao spaces within the upland Southeast Asian massif, sheltering over 80 million people belonging to geographically dispersed and politically fragmented minority populations, have only recently reopened to overseas academic endeavours. Undertaking social sciences research there among ethnic minority groups is underscored by a specific set of challenges, dilemmas, and negotiations. This special issue brings together Western academics and post-fieldwork doctoral students from the realms of social anthropology and human geography, who have conducted in-depth fieldwork among ethnic minorities in upland southwest China, northern Vietnam, and southern Laos. The articles provide insights into the struggles and constraints they faced in the field, set against an understanding of the historical context of field research in these locales. In this unique context that nowadays interweaves economic liberalisation with centralised and authoritarian political structures, the authors explore how they have negotiated and manoeuvred access to ethnic minority voices in complex cultural configurations. The ethical challenges raised and methodological reflections offered will be insightful for others conducting fieldwork in the socialist margins of the Southeast Asian massif and beyond. This specific context is introduced here, followed by a critique of the literature on the core themes that contributors raise.

  17. Patterns of Health Information Technology Use according to Sexual Orientation among US Adults Aged 50 and Older: Findings from a National Representative Sample-National Health Interview Survey 2013-2014.

    PubMed

    Lee, Ji Hyun; Giovenco, Danielle; Operario, Don

    2017-08-01

    Health disparities among sexual minority adults ages 50 and older have been documented. Factors such as lifetime discrimination and internalized stigma may deter sexual minority individuals from seeking health services. Several studies suggest that health information technology may facilitate health education and outreach to populations whose health behaviors are affected by stigma such as older sexual minority people. This study examined the role of sexual minority identity as a factor that is associated with health information technology use. Data from the 2013-2014 National Health Interview Survey (NHIS) were analyzed. Multivariate logistic regressions were used to compare the odds of using technology as a resource for health information between sexual minority versus heterosexual US adults aged 50 and older. Adjusting for sociodemographic variables and health variables, sexual minority participants had increased odds of using computers to look up health information on the Internet (OR = 2.01, 95% CI 1.53-2.64), using computers to fill a prescription (OR = 1.97, 95% CI 1.36-2.85), and using computers to communicate with health-care provider by e-mail (OR = 2.13, 95% CI 1.55-2.92), compared with heterosexuals. Findings reveal greater use of health information technology among older sexual minority adults when compared to their heterosexual counterparts. While sensitive, competent providers and culturally appropriate prevention services are essential to meeting the needs of aging sexual minority populations, health information technology use may be an innovative means of reducing disparities in information access as structural changes are implemented.

  18. Adolescent Human Immunodeficiency Virus Care Providers’ Attitudes Toward the Use of Oral Pre-Exposure Prophylaxis in Youth

    PubMed Central

    Zimet, Gregory; Lally, Michelle; Kahn, Jessica A.

    2016-01-01

    Abstract Oral pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) prevention is currently indicated for use in adults in the United States and may soon be indicated for minor adolescents. However, implementation of PrEP use among minors may present unique barriers. We conducted 15 individual, semi-structured interviews among US clinicians caring for HIV-infected and at-risk youth. The theory-driven interview guide assessed demographics, perceived role of oral PrEP in HIV prevention among adolescents, perceived barriers to and facilitating factors for use of PrEP in adolescents, and clinician-reported likelihood of prescribing PrEP. Transcripts were analyzed using framework analysis. Overall, clinicians viewed PrEP as a time-limited intervention that is one part of a comprehensive approach to HIV prevention among adolescents. Perceived barriers to prescribing to minors included concerns about: confidentiality, legality of minors consenting to PrEP without parental involvement, ability of minors to understand the risks/benefits of PrEP, the possible impact of PrEP on bone accrual, off-label use of PrEP medication in minors, and the high costs associated with PrEP use. Clinician-reported facilitating factors for prescribing PrEP to youth included educating communities and other clinicians about PrEP, ensuring adequate financial resources and infrastructure for delivering PrEP, developing formal guidance on effective behavioral interventions that should be delivered with PrEP, and gaining personal experience with prescribing PrEP. Clinicians indicated greater comfort with prescribing PrEP to adults versus minors. For PrEP to become more widely available to youth at risk for HIV infection, barriers that are unique to PrEP use in minors must be addressed. PMID:27410497

  19. Collagen type IX from human cartilage: a structural profile of intermolecular cross-linking sites.

    PubMed Central

    Diab, M; Wu, J J; Eyre, D R

    1996-01-01

    Type IX collagen, a quantitatively minor collagenous component of cartilage, is known to be associated with and covalently cross-linked to type II collagen fibrils in chick and bovine cartilage. Type IX collagen molecules have also been shown to form covalent cross-links with each other in bovine cartilage. In the present study we demonstrate by structural analysis and location of cross-linking sites that, in human cartilage, type IX collagen is covalently cross-linked to type II collagen and to other molecules of type IX collagen. We also present evidence that, if the proteoglycan form of type IX collagen is present in human cartilage, it can only be a minor component of the matrix, similar to findings with bovine cartilage. PMID:8660302

  20. A qualitative study exploring patients' experiences of standard care or cardiac rehabilitation post minor stroke and transient ischaemic attack.

    PubMed

    Hillsdon, Kaye M; Kersten, Paula; Kirk, Hayden J S

    2013-09-01

    To explore individuals' experiences of receiving either standard care or comprehensive cardiac rehabilitation post minor stroke or transient ischaemic attack. A qualitative study using semi-structured interviews, alongside a randomized controlled trial, exploring the effectiveness of comprehensive cardiac rehabilitation compared with standard care. Interviews were transcribed verbatim and subjected to thematic analysis. Individuals' homes. People who have experienced a minor stroke or transient ischaemic attack and who were partaking in a secondary prevention randomized controlled trial (6-7 months post the event, 17 males, five females; mean age 67 years). Not relevant. Not relevant. Four themes were identified: information delivery, comparing oneself with others, psychological impact, attitudes and actions regarding risk factor reduction. Participants indicated a need for improved information delivery, specific to their own risk factors and lifestyle changes. Many experienced psychological impact as a result of their minor stroke. Participants were found to make two types of social comparison; the comparison of self to another affected by stroke, and the comparison of self to cardiac patients. Comprehensive cardiac rehabilitation was reported to have positive effects on people's motivation to exercise. Following a minor stroke, many individuals do not recall information given or risk factors specific to them. Downward comparison with individuals who have had a cardiovascular event led to some underplaying the significance of their minor stroke.

  1. Ethnic Minorities’ Impression Management in the Interview: Helping or Hindering?

    PubMed Central

    Derous, Eva

    2017-01-01

    Cross-cultural impression management (IM) has not been considered much, which is remarkable given the fast rate at which the labor market is becoming multicultural. This study investigated whether ethnic minorities and majorities differed in their preference for IM-tactics and how this affected ethnic minorities’ interview outcomes. A preliminary study (focus groups/survey) showed that ethnic minorities (i.e., Arab/Moroccans) preferred ‘entitlements’ whereas majorities (i.e., Flemish/Belgians) preferred ‘opinion conformity’ as IM-tactics. An experimental follow-up study among 163 ethnic majority raters showed no main effect of IM-tactics on interview ratings. Ethnic minorities’ use of IM-tactics only affected interview ratings if rater characteristics were considered. Specifically, interview ratings were higher when ethnic minorities used opinion conformity (i.e., majority-preferred IM-tactic) and lower when minorities used entitlements (i.e., minority-preferred IM-tactic) if recruiters were high in social dominance orientation, and when they felt more experienced/proficient with interviewing. IM-tactics are a human capital factor that might help applicants to increase their job chances on the labor market. It is concluded that ethnic minority applicants’ preferences for certain IM-tactics might lead to bias even in structured interview settings, but that this depends on ethnic majority recruiters’ interview experience and ingroup/outgroup attitudes. Implications for research and practice are discussed. PMID:28203211

  2. Analysis and improved characterization of minor antioxidants from leaves of Malus doumeri using a combination of major constituents' knockout with high-performance liquid chromatography-diode array detector-quadrupole time-of-flight tandem mass spectrometry.

    PubMed

    Zhao, Huading; Hu, Xin; Chen, Xiaoqin; Shi, Shuyun; Jiang, Xinyu; Liang, Xuejuan; Chen, Wei; Zhang, Shuihan

    2015-06-12

    Due to the complexity of natural products, efficient identification of bioactive compounds, especially for minor compounds, would require a huge effort. Here, we developed an effective strategy based on combining major constituents' knockout with high-performance liquid chromatography-diode array detector-quadrupole time-of-flight tandem mass spectrometry (HPLC-DAD-QTOF-MS/MS) to comprehensively identify minor antioxidants in Malus doumeri, one of the longest known and most used tonic plant in Taiwan. First, five major compounds (I-V) in M. doumeri were knocked out by two-step stepwise high-speed countercurrent chromatography (HSCCC). Second, minor antioxidants were screened by 1,1-diphenyl-2-picrylhydrazyl radical-HPLC (DPPH-HPLC) assay. Third, structures of thirty minor antioxidants, including 11 dihydrochalcones, 4 flavanones, 3 flavonols, 2 flavones, 3 aurones and 7 phenolic acids, were unambiguously or tentatively identified by matching their characteristic UV spectra, accurate mass signals and key diagnostic fragment ions with standards or previously reported compounds. Twenty-six of them, as far as was known, were discovered from M. doumeri for the first time. The results indicated that the proposed method was a useful approach to explore minor bioactive compounds from complex natural products. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. A Grammar of Buem, the Lelemi Language.

    ERIC Educational Resources Information Center

    Allan, Edward Jay

    A detailed grammar of Buem, one of the Togo-Remnant Languages spoken in Ghana's Volta region, describes the major structures and many minor structures occurring in informal and semi-formal speech. The phonetics and much of the phonology are described in taxonomic terms, and the vowel harmony system, syntax, and morphology are described in a…

  4. Exploiting genotyping by sequencing to characterize the genomic structure of the American cranberry through high-density linkage mapping

    USDA-ARS?s Scientific Manuscript database

    The application of genotyping by sequencing (GBS) approaches, combined with data imputation methodologies, is narrowing the genetic knowledge gap between major and understudied, minor crops. GBS is an excellent tool to characterize the genomic structure of recently domesticated (~200 years) and unde...

  5. Recognition of AT-Rich DNA Binding Sites by the MogR Repressor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shen, Aimee; Higgins, Darren E.; Panne, Daniel

    2009-07-22

    The MogR transcriptional repressor of the intracellular pathogen Listeria monocytogenes recognizes AT-rich binding sites in promoters of flagellar genes to downregulate flagellar gene expression during infection. We describe here the 1.8 A resolution crystal structure of MogR bound to the recognition sequence 5' ATTTTTTAAAAAAAT 3' present within the flaA promoter region. Our structure shows that MogR binds as a dimer. Each half-site is recognized in the major groove by a helix-turn-helix motif and in the minor groove by a loop from the symmetry-related molecule, resulting in a 'crossover' binding mode. This oversampling through minor groove interactions is important for specificity.more » The MogR binding site has structural features of A-tract DNA and is bent by approximately 52 degrees away from the dimer. The structure explains how MogR achieves binding specificity in the AT-rich genome of L. monocytogenes and explains the evolutionary conservation of A-tract sequence elements within promoter regions of MogR-regulated flagellar genes.« less

  6. NMR structure of the 101-nucleotide core encapsidation signal of the Moloney murine leukemia virus.

    PubMed

    D'Souza, Victoria; Dey, Anwesha; Habib, Dina; Summers, Michael F

    2004-03-19

    The full length, positive-strand genome of the Moloney Murine Leukemia Virus contains a "core encapsidation signal" that is essential for efficient genome packaging during virus assembly. We have determined the structure of a 101-nucleotide RNA that contains this signal (called mPsi) using a novel isotope-edited NMR approach. The method is robust and should be generally applicable to larger RNAs. mPsi folds into three stem loops, two of which (SL-C and SL-D) co-stack to form an extended helix. The third stem loop (SL-B) is connected to SL-C by a flexible, four-nucleotide linker. The structure contains five mismatched base-pairs, an unusual C.CG base-triple platform, and a novel "A-minor K-turn," in which unpaired adenosine bases A340 and A341 of a GGAA bulge pack in the minor groove of a proximal stem, and a bulged distal uridine (U319) forms a hydrogen bond with the phosphodiester of A341. Phylogenetic analyses indicate that these essential structural elements are conserved among the murine C-type retroviruses.

  7. Primed for death: Law enforcement-citizen homicides, social media, and retaliatory violence.

    PubMed

    Bejan, Vladimir; Hickman, Matthew; Parkin, William S; Pozo, Veronica F

    2018-01-01

    We examine whether retaliatory violence exists between law enforcement and citizens while controlling for any social media contagion effect related to prior fatal encounters. Analyzed using a trivariate dynamic structural vector-autoregressive model, daily time-series data over a 21-month period captured the frequencies of police killed in the line of duty, police deadly use of force incidents, and social media coverage. The results support a significant retaliatory violence effect against minorities by police, yet there is no evidence of retaliatory violence against law enforcement officers by minorities. Also, social media coverage of the Black Lives Matter movement increases the risk of fatal victimization to both law enforcement officers and minorities. Possible explanations for these results are based in rational choice and terror management theories.

  8. Primed for death: Law enforcement-citizen homicides, social media, and retaliatory violence

    PubMed Central

    Bejan, Vladimir; Hickman, Matthew; Pozo, Veronica F.

    2018-01-01

    We examine whether retaliatory violence exists between law enforcement and citizens while controlling for any social media contagion effect related to prior fatal encounters. Analyzed using a trivariate dynamic structural vector-autoregressive model, daily time-series data over a 21-month period captured the frequencies of police killed in the line of duty, police deadly use of force incidents, and social media coverage. The results support a significant retaliatory violence effect against minorities by police, yet there is no evidence of retaliatory violence against law enforcement officers by minorities. Also, social media coverage of the Black Lives Matter movement increases the risk of fatal victimization to both law enforcement officers and minorities. Possible explanations for these results are based in rational choice and terror management theories. PMID:29320548

  9. Curiosity and the end of discrimination

    NASA Astrophysics Data System (ADS)

    Prescod-Weinstein, Chanda

    2017-06-01

    Systemic discrimination on the basis of gender and race, among other ascribed identities, harms minoritized people. This is a structural problem in society, and astronomy is not immune to it. Although we talk about the challenges faced by 'women and minorities', it is all too rare to acknowledge intersecting realities: some of us are minority women and our experiences are different from both white women and minority men, with sexism and racism compounding in nonlinear ways. Confronting the challenges associated with invoking an intersectional analysis can be daunting if the mainstream community continues to ignore helpful work from the social sciences, which can teach us new ways of understanding how we produce scientific knowledge. Rather than failing to question how science is done, we should let curiosity be our guide.

  10. Interactions between social/ behavioral factors and ADRB2 genotypes may be associated with health at advanced ages in China.

    PubMed

    Zeng, Yi; Cheng, Lingguo; Zhao, Ling; Tan, Qihua; Feng, Qiushi; Chen, Huashuai; Shen, Ke; Li, Jianxin; Zhang, Fengyu; Cao, Huiqing; Gregory, Simon G; Yang, Ze; Gu, Jun; Tao, Wei; Tian, Xiao-Li; Hauser, Elizabeth R

    2013-09-09

    Existing literature indicates that ADRB2 gene is associated with health and longevity, but none of previous studies investigated associations of carrying the ADRB2 minor alleles and interactions between ADRB2 genotypes and social/behavioral factors(GxE) with health outcomes at advanced ages. This study intends to fill in this research gap. We conducted an exploratory analysis, using longitudinal survey phenotype/genotype data from 877 oldest-old aged 90+. To estimate association of GxE interactions with health outcome, adjusted for the potential correlation between genotypes and social/behavioral factors and various other potentially confounding factors, we develop and test an innovative three-step procedure which combines logistic regression and structural equation methods. Interaction between regular exercise and carrying rs1042718 minor allele is significantly and positively associated with good cognitive function; interaction between regular exercise and carrying rs1042718 or rs1042719 minor allele is significantly and positively associated with self-reported good health; and interaction between social-leisure activities and carrying rs1042719 minor allele is significantly and positively associated with self-reported good health. Carrying rs1042718 or rs1042719 minor alleles is significantly and negatively associated with negative emotion, but the ADRB2 SNPs are not significantly associated with cognitive function and self-reported health. Our structural equation analysis found that, adjusted for the confounding effects of correlation of the ADRB2 SNPs with negative emotion, interaction between negative emotion and carrying rs1042718 or rs1042719 minor allele is significantly and negatively associated with cognitive function. The positive association of regular exercise and social-leisure activities with cognitive function and self-reported health, and negative association of negative emotion with cognitive function, were much stronger among carriers of rs1042718 or rs1042719 alleles, compared to the non-carriers. The results indicate significant positive associations of interactions between social/behavioral factors and the ADRB2 genotypes with health outcomes of cognitive function and self-reported health, and negative associations of carrying rs1042718 or rs1042719 minor alleles with negative emotion, at advanced ages in China. Our findings are exploratory rather than causal conclusions. This study implies that near-future health promotion programs considering individuals' genetic profiles, with appropriate protection of privacy/confidentiality, would yield increased benefits and reduced costs to the programs and their participants.

  11. Pathways to HIV risk and vulnerability among lesbian, gay, bisexual, and transgendered methamphetamine users: a multi-cohort gender-based analysis

    PubMed Central

    2011-01-01

    Background Methamphetamine (MA) use continues to be a major public health concern in many urban settings. We sought to assess potential relationships between MA use and individual, social, and structural HIV vulnerabilities among sexual minority (lesbian, gay, bisexual or transgendered) drug users. Methods Beginning in 2005 and ending in 2008, 2109 drug users were enroled into one of three cohort studies in Vancouver, Canada. We analysed longitudinal data from all self-identified sexual minority participants (n = 248). Logistic regression using generalized estimating equations (GEE) was used to examine the independent correlates of MA use over time. All analyses were stratified by biological sex at birth. Results At baseline, 104 (7.5%) males and 144 (20.4%) females reported sexual minority status, among whom 64 (62.1%) and 58 (40.3%) reported MA use in the past six months, respectively. Compared to heterosexual participants, sexual minority males (odds ratio [OR] = 3.74, p < 0.001) and females (OR = 1.80, p = 0.003) were more likely to report recent MA use. In multivariate analysis, MA use among sexual minority males was associated with younger age (adjusted odds ratio [AOR] = 0.93 per year older, p = 0.011), Aboriginal ancestry (AOR = 2.59, p = 0.019), injection drug use (AOR = 3.98, p < 0.001), having a legal order or area restriction (i.e., "no-go zone") impact access to services or influence where drugs are used or purchased (AOR = 4.18, p = 0.008), unprotected intercourse (AOR = 1.62, p = 0.048), and increased depressive symptoms (AOR = 1.67, p = 0.044). Among females, MA use was associated with injection drug use (AOR = 2.49, p = 0.002), Downtown South residency (i.e., an area known for drug use) (AOR = 1.60, p = 0.047), and unprotected intercourse with sex trade clients (AOR = 2.62, p = 0.027). Conclusions Methamphetamine use was more prevalent among sexual minority males and females and was associated with different sets of HIV risks and vulnerabilities. Our findings suggest that interventions addressing MA-related harms may need to be informed by more nuanced understandings of the intersection between drug use patterns, social and structural HIV vulnerabilities, and gender/sexual identities. In particular, MA-focused prevention and treatment programs tailored to disenfranchised male and female sexual minority youth are recommended. PMID:21214930

  12. The impact of civil union legislation on minority stress, depression, and hazardous drinking in a diverse sample of sexual-minority women: A quasi-natural experiment

    PubMed Central

    Everett, Bethany G.; Hatzenbuehler, Mark L.; Hughes, Tonda L.

    2017-01-01

    Rationale A small but growing body of research documents associations between structural forms of stigma (e.g., same-sex marriage bans) and sexual minority health. These studies, however, have focused on a limited number of outcomes and have not examined whether sociodemographic characteristics, such as race/ethnicity and education, influence the relationship between policy change and health among sexual minorities. Objective To determine the effect of civil union legalization on sexual minority women’s perceived discrimination, stigma consciousness, depressive symptoms, and four indicators of hazardous drinking (heavy episodic drinking, intoxication, alcohol dependence symptoms, adverse drinking consequences) and to evaluate whether such effects are moderated by race/ethnicity or education. Methods During the third wave of data collection in the Chicago Health and Life Experiences of Women study (N=517), Illinois passed the Religious Freedom Protection and Civil Union Act, legalizing civil unions in Illinois and resulting in a quasi-natural experiment wherein some participants were interviewed before and some after the new legislation. Generalized linear models and interactions were used to test the effects of the new legislation on stigma consciousness, perceived discrimination, depression, and hazardous drinking indicators. Interactions were used to assess whether the effects of policy change were moderated by race/ethnicity or education. Results Civil union legislation was associated with lower levels of stigma consciousness, perceived discrimination, depressive symptoms, and one indicator of hazardous drinking (adverse drinking consequences) for all sexual minority women. For several other outcomes, the benefits of this supportive social policy were largely concentrated among racial/ethnic minority women and women with lower levels of education. Conclusions Results suggest that policies supportive of the civil rights of sexual minorities improve the health of all sexual minority women, and may be most beneficial for women with multiply marginalized statuses. PMID:27733300

  13. The impact of civil union legislation on minority stress, depression, and hazardous drinking in a diverse sample of sexual-minority women: A quasi-natural experiment.

    PubMed

    Everett, Bethany G; Hatzenbuehler, Mark L; Hughes, Tonda L

    2016-11-01

    A small but growing body of research documents associations between structural forms of stigma (e.g., same-sex marriage bans) and sexual minority health. These studies, however, have focused on a limited number of outcomes and have not examined whether sociodemographic characteristics, such as race/ethnicity and education, influence the relationship between policy change and health among sexual minorities. To determine the effect of civil union legalization on sexual minority women's perceived discrimination, stigma consciousness, depressive symptoms, and four indicators of hazardous drinking (heavy episodic drinking, intoxication, alcohol dependence symptoms, adverse drinking consequences) and to evaluate whether such effects are moderated by race/ethnicity or education. During the third wave of data collection in the Chicago Health and Life Experiences of Women study (N = 517), Illinois passed the Religious Freedom Protection and Civil Union Act, legalizing civil unions in Illinois and resulting in a quasi-natural experiment wherein some participants were interviewed before and some after the new legislation. Generalized linear models and interactions were used to test the effects of the new legislation on stigma consciousness, perceived discrimination, depression, and hazardous drinking indicators. Interactions were used to assess whether the effects of policy change were moderated by race/ethnicity or education. Civil union legislation was associated with lower levels of stigma consciousness, perceived discrimination, depressive symptoms, and one indicator of hazardous drinking (adverse drinking consequences) for all sexual minority women. For several other outcomes, the benefits of this supportive social policy were largely concentrated among racial/ethnic minority women and women with lower levels of education. Results suggest that policies supportive of the civil rights of sexual minorities improve the health of all sexual minority women, and may be most beneficial for women with multiply marginalized statuses. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Detection of specific IgE antibodies to major and minor antigenic determinants in sera of penicillin allergic patients.

    PubMed

    Zhao, Yongxing; Qiao, Hailing

    2003-12-01

    To investigate the mechanism(s) of penicillins allergic reaction. The radioallergosorbent test (RAST) was used to detect 9 specific IgE antibodies, including major antigenic determinants: benzylpenicilloyl (BPO), ampicilloyl (APO), amoxicilloyl (AXO), phenoxomethylpenicilloyl (PVO) and flucloxacilloyl (FLUO), and minor antigenic determinants: benzylpenicillanyl (BPA), amoxicillanyl (AXA), 6-aminopenicillanic (APA) and phenoxomethylpenicillany (PVA), in the sera of 32 penicillin allergic patients. The relationship between specific IgE antibodies and penicillins chemical structures was studied by radioallergosorbent inhibition test. Nineteen of 32 patients (59.4%) were RAST positive, among whom, five cases were positive only to one or two antigenic minor determinants, and three cases were positive only to one or three major antigenic determinants. The remaining 11 patients were positive not only to major antigenic determinants but also minor antigenic determinants. In 9 specific IgE antibodies, the positive rate of PVA-IgE was the highest (34.38%), followed by BPO-IgE (31.25%). The positive rate of FLUO-IgE was the lowest (15.63%). Of the total patient group, 53.13% were positive to one or more minor antigenic determinants, while 37.5% (12/32) were positive to one or more major antigenic determinants. The percentage of patients with urticarial reactions who were positive to minor antigenic determinants (63.16%) was significantly higher than observed in the anaphylactic shock group (38.5%, P < 0.05). The minor antigenic determinant was important in allergic reaction. The combining sites of the specific IgE antibodies were likely to be the side-chain of drug or the overwhelming drug molecule.

  15. Happiness and Sexual Minority Status

    PubMed Central

    Thomeer, Mieke Beth; Reczek, Corinne

    2017-01-01

    We used logistic regression on nationally representative data (General Social Survey, N = 10,668 and N = 6,680) to examine how sexual minority status related to happiness. We considered two central dimensions of sexual minority status—sexual behavior and sexual identity. We distinguished between same-sex, both-sex, and different-sex oriented participants. Because individuals transition between sexual behavior categories over the life course (e.g., from both-sex partners to only same-sex partners) and changes in sexual minority status have theoretical associations with well-being, we also tested the effects of transitions on happiness. Results showed that identifying as bisexual, gay, or lesbian, having both male and female partners since age 18, or transitioning to only different-sex partners was negatively related to happiness. Those with only same-sex partners since age 18 or in the past five years had similar levels of happiness as those with only different-sex partners since age 18. Additional tests showed that the majority of these happiness differences became non-significant when economic and social resources were included, indicating that the lower happiness was a product of structural and societal forces. Our findings clearly and robustly underscored the importance of taking a multi-faceted approach to understanding sexuality and well-being, demonstrating that not all sexual minority groups experience disadvantaged happiness. Our study calls for more attention to positive aspects of well-being such as happiness in examinations of sexual minorities and suggests that positive psychology and other happiness subfields should consider the role of sexual minority status in shaping happiness. PMID:27102605

  16. Happiness and Sexual Minority Status.

    PubMed

    Thomeer, Mieke Beth; Reczek, Corinne

    2016-10-01

    We used logistic regression on nationally representative data (General Social Survey, N = 10,668 and N = 6680) to examine how sexual minority status related to happiness. We considered two central dimensions of sexual minority status-sexual behavior and sexual identity. We distinguished between same-sex, both-sex, and different-sex-oriented participants. Because individuals transition between sexual behavior categories over the life course (e.g., from both-sex partners to only same-sex partners) and changes in sexual minority status have theoretical associations with well-being, we also tested the associations of transitions with happiness. Results showed that identifying as bisexual, gay, or lesbian, having both male and female partners since age 18, or transitioning to only different-sex partners was negatively related to happiness. Those with only same-sex partners since age 18 or in the past 5 years had similar levels of happiness as those with only different-sex partners since age 18. Additional tests showed that the majority of these happiness differences became non-significant when economic and social resources were included, indicating that the lower happiness was a product of structural and societal forces. Our findings clearly and robustly underscored the importance of taking a multi-faceted approach to understanding sexuality and well-being, demonstrating that not all sexual minority groups experience disadvantaged happiness. Our study calls for more attention to positive aspects of well-being such as happiness in examinations of sexual minorities and suggests that positive psychology and other happiness subfields should consider the role of sexual minority status in shaping happiness.

  17. Discovery of microscopic evidence for shock metamorphism at the Serpent Mound structure, south-central Ohio: Confirmation of an origin by impact

    USGS Publications Warehouse

    Carlton, R.W.; Koeberl, C.; Baranoski, M.T.; SchuMacHer, G.A.

    1998-01-01

    The origin of the Serpent Mound structure in south-central Ohio has been disputed for many years. Clearly, more evidence was needed to resolve the confusion concerning the origin of the Serpent Mound feature either by endogenic processes or by hypervelocity impact. A petrographic study of 21 samples taken from a core 903 m long drilled in the central uplift of the structure provides evidence of shock metamorphism in the form of multiple sets of planar deformation features in quartz grains, as well as the presence of clasts of altered impact-melt rock. Crystallographic orientations of the planar deformation features show maxima at the shock-characteristic planes of {101??3} and {101??2} and additional maxima at {101??1}, {213??1}, and {516??1}. Geochemical analyses of impact breccias show minor enrichments in the abundances of the siderophile elements Cr, Co, Ni, and Ir, indicating the presence of a minor meteoritic component.

  18. Methylene blue binding to DNA with alternating AT base sequence: minor groove binding is favored over intercalation.

    PubMed

    Rohs, Remo; Sklenar, Heinz

    2004-04-01

    The results presented in this paper on methylene blue (MB) binding to DNA with AT alternating base sequence complement the data obtained in two former modeling studies of MB binding to GC alternating DNA. In the light of the large amount of experimental data for both systems, this theoretical study is focused on a detailed energetic analysis and comparison in order to understand their different behavior. Since experimental high-resolution structures of the complexes are not available, the analysis is based on energy minimized structural models of the complexes in different binding modes. For both sequences, four different intercalation structures and two models for MB binding in the minor and major groove have been proposed. Solvent electrostatic effects were included in the energetic analysis by using electrostatic continuum theory, and the dependence of MB binding on salt concentration was investigated by solving the non-linear Poisson-Boltzmann equation. We find that the relative stability of the different complexes is similar for the two sequences, in agreement with the interpretation of spectroscopic data. Subtle differences, however, are seen in energy decompositions and can be attributed to the change from symmetric 5'-YpR-3' intercalation to minor groove binding with increasing salt concentration, which is experimentally observed for the AT sequence at lower salt concentration than for the GC sequence. According to our results, this difference is due to the significantly lower non-electrostatic energy for the minor groove complex with AT alternating DNA, whereas the slightly lower binding energy to this sequence is caused by a higher deformation energy of DNA. The energetic data are in agreement with the conclusions derived from different spectroscopic studies and can also be structurally interpreted on the basis of the modeled complexes. The simple static modeling technique and the neglect of entropy terms and of non-electrostatic solute-solvent interactions, which are assumed to be nearly constant for the compared complexes of MB with DNA, seem to be justified by the results.

  19. Contour mapping of relic structures in the Precambrian basement of the Reelfoot rift, North American midcontinent

    USGS Publications Warehouse

    Dart, R.L.; Swolfs, H.S.

    1998-01-01

    A new contour map of the basement of the Reelfoot rift constructed from drill hole and seismic reflection data shows the general surface configuration as well as several major and minor structural features. The major features are two asymmetric intrarift basins, bounded by three structural highs, and the rift margins. The basins are oriented normal to the northeast trend of the rift. Two of the highs appear to be ridges of undetermined width that extend across the rift. The third high is an isolated dome or platform located between the basins. The minor features are three linear structures of low relief oriented subparallel to the trend of the rift. Two of these, located within the rift basins, may divide the rift basins into paired subbasins. These mapped features may be the remnants of initial extensional rifting, half graben faulting, and basement subsidence. The rift basins are interpreted as having formed as opposing half graben, and the structural highs are interpreted as having formed as associated accommodation zones. Some of these features appear to be reactivated seismogenic structures within the modem midcontinent compressional stress regime. A detailed knowledge of the geometries of the Reelfoot rift's basement features, therefore, is essential when evaluating their seismic risk potential.

  20. Proceedings of the NATO Advanced Study Institute on Physics and Applications of Quantum Wells and Superlattices Held in Erice, Italy on 21 April - 1 May 1987. Series B. Volume 170

    DTIC Science & Technology

    1987-05-01

    possibilities and the latter providing a photodetector with low dark currents . Some mention will also be made of structures devised by Nakagawa7 ,8...developments concerning the growth and the characterization of Hgl_xCdxTe-Cdte SLs and related Hg based superlattice systems. These SLs are now currently ...minority carriers in the base region. When a current is flowing, the drift velocities of minority and majority carriers are oppositely directed, and

  1. AstroCom NYC: A Partnership to Support Underrepresented Minorities in Astronomy and Astrophysics Research and Education

    NASA Astrophysics Data System (ADS)

    Ford, K. E. Saavik; Paglione, Timothy; Robbins, Dennis; Mac Low, Mordecai-Mark; Agueros, Marcel A.

    2015-01-01

    AstroCom NYC is an NSF-funded partnership between astronomers at The City University of New York (CUNY), The American Museum of Natural History (AMNH) and Columbia University, designed to increase recruitment and retention of underrepresented minorities in astronomy and astrophysics. I will discuss the major program elements, including: recruitment, student selection, a 'Methods of Scientific Research' (MSR) course, summer research experience and ongoing structured mentoring. I will also discuss how the programs are integrated into each institution and present progress updates from our first two years.

  2. The Interaction between Family Structure and Child Gender on Behavior Problems in Urban Ethnic Minority Children

    ERIC Educational Resources Information Center

    Mokrue, Kathariya; Chen, Yung Y.; Elias, Maurice

    2012-01-01

    Previous studies have reported that children from single-parent households fare worse behaviorally than those from two-parent households. Studies examining single-parent households often fail to distinguish between single-mother and single-father households. Further, there are inconsistent findings regarding the effect of family structure on boys…

  3. Validation of molecular crystal structures from powder diffraction data with dispersion-corrected density functional theory (DFT-D).

    PubMed

    van de Streek, Jacco; Neumann, Marcus A

    2014-12-01

    In 2010 we energy-minimized 225 high-quality single-crystal (SX) structures with dispersion-corrected density functional theory (DFT-D) to establish a quantitative benchmark. For the current paper, 215 organic crystal structures determined from X-ray powder diffraction (XRPD) data and published in an IUCr journal were energy-minimized with DFT-D and compared to the SX benchmark. The on average slightly less accurate atomic coordinates of XRPD structures do lead to systematically higher root mean square Cartesian displacement (RMSCD) values upon energy minimization than for SX structures, but the RMSCD value is still a good indicator for the detection of structures that deserve a closer look. The upper RMSCD limit for a correct structure must be increased from 0.25 Å for SX structures to 0.35 Å for XRPD structures; the grey area must be extended from 0.30 to 0.40 Å. Based on the energy minimizations, three structures are re-refined to give more precise atomic coordinates. For six structures our calculations provide the missing positions for the H atoms, for five structures they provide corrected positions for some H atoms. Seven crystal structures showed a minor error for a non-H atom. For five structures the energy minimizations suggest a higher space-group symmetry. For the 225 SX structures, the only deviations observed upon energy minimization were three minor H-atom related issues. Preferred orientation is the most important cause of problems. A preferred-orientation correction is the only correction where the experimental data are modified to fit the model. We conclude that molecular crystal structures determined from powder diffraction data that are published in IUCr journals are of high quality, with less than 4% containing an error in a non-H atom.

  4. Validation of molecular crystal structures from powder diffraction data with dispersion-corrected density functional theory (DFT-D)

    PubMed Central

    van de Streek, Jacco; Neumann, Marcus A.

    2014-01-01

    In 2010 we energy-minimized 225 high-quality single-crystal (SX) structures with dispersion-corrected density functional theory (DFT-D) to establish a quantitative benchmark. For the current paper, 215 organic crystal structures determined from X-ray powder diffraction (XRPD) data and published in an IUCr journal were energy-minimized with DFT-D and compared to the SX benchmark. The on average slightly less accurate atomic coordinates of XRPD structures do lead to systematically higher root mean square Cartesian displacement (RMSCD) values upon energy minimization than for SX structures, but the RMSCD value is still a good indicator for the detection of structures that deserve a closer look. The upper RMSCD limit for a correct structure must be increased from 0.25 Å for SX structures to 0.35 Å for XRPD structures; the grey area must be extended from 0.30 to 0.40 Å. Based on the energy minimizations, three structures are re-refined to give more precise atomic coordinates. For six structures our calculations provide the missing positions for the H atoms, for five structures they provide corrected positions for some H atoms. Seven crystal structures showed a minor error for a non-H atom. For five structures the energy minimizations suggest a higher space-group symmetry. For the 225 SX structures, the only deviations observed upon energy minimization were three minor H-atom related issues. Preferred orientation is the most important cause of problems. A preferred-orientation correction is the only correction where the experimental data are modified to fit the model. We conclude that molecular crystal structures determined from powder diffraction data that are published in IUCr journals are of high quality, with less than 4% containing an error in a non-H atom. PMID:25449625

  5. Altervalent substitution of sodium for calcium in biogenic calcite and aragonite

    NASA Astrophysics Data System (ADS)

    Yoshimura, Toshihiro; Tamenori, Yusuke; Suzuki, Atsushi; Kawahata, Hodaka; Iwasaki, Nozomu; Hasegawa, Hiroshi; Nguyen, Luan T.; Kuroyanagi, Azumi; Yamazaki, Toshitsugu; Kuroda, Junichiro; Ohkouchi, Naohiko

    2017-04-01

    Sodium concentrations in biogenic CaCO3 are several thousands of parts per million, and, on a molar basis, Na is among the most abundant constituent minor element in these carbonates. Nevertheless, the chemical form of Na in CaCO3 is not well constrained. We used synchrotron X-ray spectroscopy to identify the dominant molecular host sites for Na in biogenic calcite and aragonite precipitated by corals, bivalves, and foraminifera. We also used the K-edge X-ray absorption near-edge structure to investigate the chemical environment of Na in biogenic calcium carbonates and identify the altervalent substitution of Na into Ca sites in the lattice structures of calcite and aragonite. Minor cation and anion concentrations in biogenic CaCO3 suggest that the principal substitution mechanism involves charge compensation through the creation of CO32- vacancies. The mostly homogeneous Na concentrations in the skeletal microstructures of the various biota we examined indicate that environmental and biological controls, such as temperature, skeletal microstructure, and calcification rates, have only minor influences on skeletal Na concentrations. A decrease of Na:Ca ratios with increasing age of foraminiferal shells picked from a Quaternary sediment core, indicates progressive release of Na, which suggests that structurally-substituted Na in biogenic CaCO3 is readily leached during burial diagenesis. Whereas the sediment that undergo diagenesis release some Na back to the water column, sodium co-precipitation in biogenic CaCO3 serves as a potential sink of Na for the ocean.

  6. Structure-guided Mutational Analysis of the OB, HhH, and BRCT Domains of Escherichia coli DNA Ligase*S⃞

    PubMed Central

    Wang, Li Kai; Nair, Pravin A.; Shuman, Stewart

    2008-01-01

    NAD+-dependent DNA ligases (LigAs) are ubiquitous in bacteria and essential for growth. LigA enzymes have a modular structure in which a central catalytic core composed of nucleotidyltransferase and oligonucleotide-binding (OB) domains is linked via a tetracysteine zinc finger to distal helix-hairpin-helix (HhH) and BRCT (BRCA1-like C-terminal) domains. The OB and HhH domains contribute prominently to the protein clamp formed by LigA around nicked duplex DNA. Here we conducted a structure-function analysis of the OB and HhH domains of Escherichia coli LigA by alanine scanning and conservative substitutions, entailing 43 mutations at 22 amino acids. We thereby identified essential functional groups in the OB domain that engage the DNA phosphodiester backbone flanking the nick (Arg333); penetrate the minor grove and distort the nick (Val383 and Ile384); or stabilize the OB fold (Arg379). The essential constituents of the HhH domain include: four glycines (Gly455, Gly489, Gly521, Gly553), which bind the phosphate backbone across the minor groove at the outer margins of the LigA-DNA interface; Arg487, which penetrates the minor groove at the outer margin on the 3 ®-OH side of the nick; and Arg446, which promotes protein clamp formation via contacts to the nucleotidyltransferase domain. We find that the BRCT domain is required in its entirety for effective nick sealing and AMP-dependent supercoil relaxation. PMID:18515356

  7. Structure-guided mutational analysis of the OB, HhH, and BRCT domains of Escherichia coli DNA ligase.

    PubMed

    Wang, Li Kai; Nair, Pravin A; Shuman, Stewart

    2008-08-22

    NAD(+)-dependent DNA ligases (LigAs) are ubiquitous in bacteria and essential for growth. LigA enzymes have a modular structure in which a central catalytic core composed of nucleotidyltransferase and oligonucleotide-binding (OB) domains is linked via a tetracysteine zinc finger to distal helix-hairpin-helix (HhH) and BRCT (BRCA1-like C-terminal) domains. The OB and HhH domains contribute prominently to the protein clamp formed by LigA around nicked duplex DNA. Here we conducted a structure-function analysis of the OB and HhH domains of Escherichia coli LigA by alanine scanning and conservative substitutions, entailing 43 mutations at 22 amino acids. We thereby identified essential functional groups in the OB domain that engage the DNA phosphodiester backbone flanking the nick (Arg(333)); penetrate the minor grove and distort the nick (Val(383) and Ile(384)); or stabilize the OB fold (Arg(379)). The essential constituents of the HhH domain include: four glycines (Gly(455), Gly(489), Gly(521), Gly(553)), which bind the phosphate backbone across the minor groove at the outer margins of the LigA-DNA interface; Arg(487), which penetrates the minor groove at the outer margin on the 3 (R)-OH side of the nick; and Arg(446), which promotes protein clamp formation via contacts to the nucleotidyltransferase domain. We find that the BRCT domain is required in its entirety for effective nick sealing and AMP-dependent supercoil relaxation.

  8. SEPARATION AND PURIFICATION OF TWO MINOR COMPOUNDS FROM RADIX ISATIDIS BY INTEGRATIVE MPLC AND HSCCC WITH PREPARATIVE HPLC.

    PubMed

    Liang, Zhenjie; Li, Bin; Liang, Yong; Su, Yaping; Ito, Yoichiro

    2015-01-01

    Radix isatidis has been widely used as a Chinese traditional medicine for its anti-virus and anticancer activities where the minor components may contribute to these beneficial pharmaceutical effects. In order to enrich the target minor compounds effectively and rapidly, extraction, medium-pressure liquid chromatography (MPLC), high-speed countercurrent chromatography (HSCCC) and preparative high-performance liquid chromatography (pre-HPLC) were integratively used for separation and purification of two target minor compounds indole-3-acetonitrile-6-O-β-D-glucopyranoside (target 1) and clemastanin B (target 2) in the present study. Radix isatidis was dried, pulverized and extracted with 50% methanol at room temperature, then concentrated and subjected to pretreatment with D-101 macroporous resin chromatography and extraction by MPLC. The first target compound was separated by MPLC at the purity raised to 70-80%, but without the second minor compounds which were irreversibly adsorbed by C18 solid support. Therefore, the second target compound in the crude extract was directly separated by HSCCC at purity of 80-90%. Finally these refined samples were further separated by pre-HPLC to obtain a high purity at 98-99%. The chemical structure identification of each target compound was carried out by IR, ESI-MS and 1 H NMR.

  9. Encouraging minority undergraduates to choose science careers: career paths survey results.

    PubMed

    Villarejo, Merna; Barlow, Amy E L; Kogan, Deborah; Veazey, Brian D; Sweeney, Jennifer K

    2008-01-01

    To explore the reasons for the dearth of minorities in Ph.D.-level biomedical research and identify opportunities to increase minority participation, we surveyed high-achieving alumni of an undergraduate biology enrichment program for underrepresented minorities. Respondents were asked to describe their career paths and to reflect on the influences that guided their career choices. We particularly probed for attitudes and experiences that influenced students to pursue a research career, as well as factors relevant to their choice between medicine (the dominant career choice) and basic science. In agreement with earlier studies, alumni strongly endorsed supplemental instruction as a mechanism for achieving excellence in basic science courses. Undergraduate research was seen as broadening by many and was transformative for half of the alumni who ultimately decided to pursue Ph.D.s in biomedical research. That group had expressed no interest in research careers at college entry and credits their undergraduate research experience with putting them on track toward a research career. A policy implication of these results is that making undergraduate research opportunities widely available to biology students (including "premed" students) in the context of a structured educational enrichment program should increase the number of minority students who choose to pursue biomedical Ph.D.s.

  10. Highlighting Successful Strategies for Engaging Minority Students in the Geosciences

    NASA Astrophysics Data System (ADS)

    Liou-Mark, J.; Blake, R.; Norouzi, H.; Vladutescu, D. V.; Yuen-Lau, L.

    2017-12-01

    Igniting interest and creativity in students for the geosciences oftentimes require innovation, bold `outside-the-box' thinking, and perseverance, particularly for minority students for whom the preparation for the discipline and its lucrative pathways to the geoscience workforce are regrettably unfamiliar and woefully inadequate. The enrollment, retention, participation, and graduation rates of minority students in STEM generally and in the geosciences particularly remain dismally low. However, a coupled, strategic geoscience model initiative at the New York City College of Technology (City Tech) of the City University of New York has been making steady in-roads of progress, and it offers practical solutions to improve minority student engagement in the geosciences. Aided by funding from the National Science Foundation (NSF), two geoscience-centric programs were created from NSF REU and NSF IUSE grants, and these programs have been successfully implemented and administered at City Tech. This presentation shares the hybrid geoscience research initiatives, the multi-tiered mentoring structures, the transformative geoscience workforce preparation, and a plethora of other vital bastions of support that made the overall program successful. Minority undergraduate scholars of the program have either moved on to graduate school, to the geoscience workforce, or they persist with greater levels of success in their STEM disciplines.

  11. Effect of Genetic Variant in BICC1 on Functional and Structural Brain Changes in Depression

    PubMed Central

    Bermingham, Rachel; Carballedo, Angela; Lisiecka, Danuta; Fagan, Andrew; Morris, Derek; Fahey, Ciara; Donohoe, Gary; Meaney, James; Gill, Michael; Frodl, Thomas

    2012-01-01

    Genes and early-life adversity (ELA) interactively increase the risk of developing major depressive disorder (MDD). A recent genome-wide association study suggests that the minor T-allele of single-nucleotide polymorphisms in the bicaudal C homolog 1 gene (BICC1) has a protective role against MDD. The aims of the study were to investigate whether the minor T-allele of BICC1 is protective against hippocampal structural brain changes, whether it is associated with increased functional brain activity in the emotion regulation system, and how ELA would modify this association. Forty-four patients with MDD and 44 healthy controls were investigated using structural magnetic resonance imaging (MRI) and functional MRI with an emotion inhibition task. Analysis of a single-nucleotide polymorphism in the BICC1-1 (rs999845) gene was performed. Right hippocampal bodies of patients and controls without a history of ELA and who carry the protective T-allele of BICC1 were significantly larger compared with those participants homozygous for the major C-allele of BICC1. However, MDD patients with ELA, who carry the T-allele, had smaller hippocampal head volumes compared with MDD patients without ELA. FMRI showed that patients and controls carrying the protective T-allele of BICC1 activate the emotion regulation system significantly more compared with those participants homozygous for the major C-allele (p<0.05, family wise error corrected). These results are suggestive that the minor T-allele of BICC1 has a protective role against MDD and its known structural and functional brain changes. However, this protective effect seems to be lost in the case of co-occurrence of ELA. PMID:22910460

  12. DFT calculations of strain and interface effects on electronic structures and magnetic properties of L10-FePt/Ag heterojunction of GMR applications

    NASA Astrophysics Data System (ADS)

    Pramchu, Sittichain; Jaroenjittichai, Atchara Punya; Laosiritaworn, Yongyut

    2018-03-01

    In this work, density functional theory (DFT) was employed to investigate the effect of strain and interface on electronic structures and magnetic properties of L10-FePt/Ag heterojunction. Two possible interface structures of L10-FePt(001)/Ag(001), that is, interface between Fe and Ag layers (Fe/Ag) and between Pt and Ag layers (Pt/Ag), were inspected. It was found that Pt/Ag interface is more stable than Fe/Ag interface due to its lower formation energy. Further, under the lattice mismatch induced tensile strain, the enhancement of magnetism for both Fe/Ag and Pt/Ag interface structures has been found to have progressed, though the magnetic moments of "interfacial" Fe and Pt atoms have been found to have decreased. To explain this further, the local density of states (LDOS) analysis suggests that interaction between Fe (Pt) and Ag near Fe/Ag (Pt/Ag) interface leads to spin symmetry breaking of the Ag atom and hence induces magnetism magnitude. In contrast, the magnetic moments of interfacial Fe and Pt atoms reduce because of the increase in the electronic states near the Fermi level of the minority-spin electrons. In addition, the significant enhancements of the LDOS near the Fermi levels of the minority-spin electrons signify the boosting of the transport properties of the minority-spin electrons and hence the spin-dependent electron transport at this ferromagnet/metal interface. From this work, it is expected that this clarification of the interfacial magnetism may inspire new innovation on how to improve spin-dependent electron transport for enhancing the giant magnetoresistance (GMR) ratio of potential GMR-based spintronic devices.

  13. The Need for High Fidelity Lunar Regolith Simulants

    NASA Technical Reports Server (NTRS)

    Gaier, James R.

    2007-01-01

    The case is made for the need to have high fidelity lunar regolith simulants to verify the performance of structures and mechanisms to be used on the lunar surface. Minor constituents will in some cases have major consequences. Small amounts of sulfur in the regolith can poison catalysts, and metallic iron on the surface of nano-sized dust particles may cause a dramatic increase in its toxicity. So the definition of a high fidelity simulant is application dependent. For example, in situ resource utilization will require high fidelity in chemistry, meaning careful attention to the minor components and phases; but some other applications, such as the abrasive effects on suit fabrics, might be relatively insensitive to minor component chemistry. The lunar environment itself will change the surface chemistry of the simulant, so to have a high fidelity simulant at must be used in a high fidelity simulated environment to get a high fidelity simulation. Research must be conducted to determine how sensitive technologies will be to minor components and environmental factors before they can be dismissed as unimportant.

  14. Mindfulness as a Coping Strategy for Bias-Based School Victimization among Latina/o Sexual Minority Youth

    PubMed Central

    Toomey, Russell B.; Anhalt, Karla

    2016-01-01

    This study examined whether mindfulness strategies (e.g., acting non-judgmentally with awareness and attention to present events) were effective in mitigating the associations among school-based victimization related to ethnicity and sexual orientation, well-being (i.e., depressive symptoms and self-esteem), and grade-point average (GPA). The U.S.-based sample included 236 Latina/o sexual minority students, ranging in age from 14 to 24 years (47% were enrolled in secondary schools, 53% in postsecondary schools). Results from structural equation modeling revealed that ethnicity-based school victimization was negatively associated with GPA but not well-being. However, sexual orientation-based victimization was not associated with well-being or GPA. Mindfulness was positively associated with well-being but not GPA. High levels of mindfulness coping were protective when the stressor was sexual orientation-based victimization but not ethnicity-based school victimization. These findings contribute to a growing literature documenting the unique school barriers experienced by Latina/o sexual minority youth and highlight the promising utility of mindfulness-based intervention strategies for coping with minority stress. PMID:28018933

  15. The Minority Fellowship Program: a 30-year legacy of training psychologists of color.

    PubMed

    Jones, James M; Austin-Dailey, Andrew T

    2009-10-01

    This article traces the development and growth of the American Psychological Association (APA) Minority Fellowship Program (MFP) from is inception in 1974 to 2007. The original influences of Black psychiatrists in creating the Center for Minority Group Mental Health at the National Institute of Mental Health are described, and the initial structure and strategy of MFP is outlined. The dramatic growth in the number of MFP Fellows (82%), the average size of Fellowship stipends (810%), and the total stipend dollars (1,560%) reflects expansion of the programs in substance abuse research, treatment and prevention, neuroscience and human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS), as well as mental health service and research. The influence of the MFP on the APA and departments of psychology are described, including the role the MFP played in the establishment of the Office, Board, and Committee of Ethnic Minority Affairs. Some of the accomplishments and leadership roles MFP alumni have played are described. The article concludes with a discussion of the current status of MFP and projections for the future. Copyright 2009 APA, all rights reserved.

  16. Stigma, Mental Health, and Resilience in an Online Sample of the US Transgender Population

    PubMed Central

    Miner, Michael H.; Swinburne Romine, Rebecca E.; Hamilton, Autumn; Coleman, Eli

    2013-01-01

    Objectives. We assessed the association between minority stress, mental health, and potential ameliorating factors in a large, community-based, geographically diverse sample of the US transgender population. Methods. In 2003, we recruited through the Internet a sample of 1093 male-to-female and female-to-male transgender persons, stratified by gender. Participants completed an online survey that included standardized measures of mental health. Guided by the minority stress model, we evaluated associations between stigma and mental health and tested whether indicators of resilience (family support, peer support, identity pride) moderated these associations. Results. Respondents had a high prevalence of clinical depression (44.1%), anxiety (33.2%), and somatization (27.5%). Social stigma was positively associated with psychological distress. Peer support (from other transgender people) moderated this relationship. We found few differences by gender identity. Conclusions. Our findings support the minority stress model. Prevention needs to confront social structures, norms, and attitudes that produce minority stress for gender-variant people; enhance peer support; and improve access to mental health and social services that affirm transgender identity and promote resilience. PMID:23488522

  17. Assignment of polarization-dependent peaks in carbon K-edge spectra from biogenic and geologic aragonite.

    PubMed

    Zhou, Dong; Metzler, Rebecca A; Tyliszczak, Tolek; Guo, Jinghua; Abrecht, Mike; Coppersmith, Susan N; Gilbert, P U P A

    2008-10-16

    Many biominerals, including mollusk and echinoderm shells, avian eggshells, modern and fossil bacterial sediments, planktonic coccolithophores, and foraminifera, contain carbonates in the form of biogenic aragonite or calcite. Here we analyze biogenic and geologic aragonite using different kinds of surface- and bulk-sensitive X-ray absorption near-edge structure (XANES) spectroscopy at the carbon K-edge, as well as high-resolution scanning transmission X-ray microscopy (STXM). Besides the well-known main pi* and sigma* carbonate peaks, we observed and fully characterized four minor peaks, at energies between the main pi* and sigma* peaks. As expected, the main peaks are similar in geologic and biogenic aragonite, while the minor peaks differ in relative intensity. In this and previous work, the minor peaks appear to be the ones most affected in biomineralization processes, hence the interest in characterizing them. Peak assignment was achieved by correlation of polarization-dependent behavior of the minor peaks with that of the main pi* and sigma* peaks. The present characterization provides the background for future studies of aragonitic biominerals.

  18. The Need for High Fidelity Lunar Regolith Simulants

    NASA Technical Reports Server (NTRS)

    Gaier, James R.

    2008-01-01

    The case is made for the need to have high fidelity lunar regolith simulants to verify the performance of structures, mechanisms, and processes to be used on the lunar surface. Minor constituents will in some cases have major consequences. Small amounts of sulfur in the regolith can poison catalysts, and metallic iron on the surface of nano-sized dust particles may cause a dramatic increase in its toxicity. So the definition of a high fidelity simulant is application-dependent. For example, in situ resource utilization will require high fidelity in chemistry, meaning careful attention to the minor components and phases; but some other applications, such as the abrasive effects on suit fabrics, might be relatively insensitive to minor component chemistry while abrasion of some metal components may be highly dependent on trace components. The lunar environment itself will change the surface chemistry of the simulant, so to have a high fidelity simulant it must be used in a high fidelity simulated environment to get an accurate simulation. Research must be conducted to determine how sensitive technologies will be to minor components and environmental factors before they can be dismissed as unimportant.

  19. Finding a Needle in the Haystack: Identification of Functionally Important Minority Phases in an Operating Battery.

    PubMed

    Zhang, Kai; Ren, Fang; Wang, Xuelong; Hu, Enyuan; Xu, Yahong; Yang, Xiao-Qing; Li, Hong; Chen, Liquan; Pianetta, Piero; Mehta, Apurva; Yu, Xiqian; Liu, Yijin

    2017-12-13

    The in-depth understanding of the minority phases' roles in functional materials, e.g., batteries, is critical for optimizing the system performance and the operational efficiency. Although the visualization of battery electrode under operating conditions has been demonstrated, the development of advanced data-mining approaches is still needed in order to identify minority phases and to understand their functionalities. The present study uses nanoscale X-ray spectromicroscopy to study a functional LiCoO 2 /Li battery pouch cell. The data-mining approaches developed herein were used to search through over 10 million X-ray absorption spectra that cover more than 100 active cathode particles. Two particles with unanticipated chemical fingerprints were identified and further analyzed, providing direct evidence and valuable insight into the undesired side reactions involving the cation dissolution and precipitation as well as the local overlithiation-caused subparticle domain deactivation. The data-mining approach described in this work is widely applicable to many other structurally complex and chemically heterogeneous systems, in which the secondary/minority phases could critically affect the overall performance of the system, well beyond battery research.

  20. "Skinny is prettier and normal: I want to be normal"-Perceived body image of non-Western ethnic minority children in the Netherlands.

    PubMed

    Veldhuis, Jolanda; Te Poel, Fam; Pepping, Rian; Konijn, Elly A; Spekman, Marloes L C

    2017-03-01

    While the prevalence of overweight and obesity is higher among children of some non-Western ethnic minorities than among their Caucasian counterparts, their body image is understudied. The current study examined the body image of Dutch children of non-Western ethnic minorities (i.e., Surinamese, Antillean, Moroccan, and Turkish). Sociocultural influences from school, media and home environments and their perceptions of overweight prevention programs were taken into account. Fifty-two non-Western ethnic minority children (aged 8-12 years) participated in semi-structured interviews and focus groups. Results showed that the children generally underestimated their current body size, which was often overweight, and preferred thin and 'normal' body sizes. Results further revealed important insights into culturally determined themes, relating to perceived preferences in media, peers, parents, and teachers, nutritional habits, and children's beliefs about school-based health interventions. We conclude that targeting culturally sensitive awareness about actual body size and healthy body images seems paramount in future interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Ethnic density as a buffer for psychotic experiences: findings from a national survey (EMPIRIC)†

    PubMed Central

    Das-Munshi, Jayati; Bécares, Laia; Boydell, Jane E.; Dewey, Michael E.; Morgan, Craig; Stansfeld, Stephen A.; Prince, Martin J.

    2012-01-01

    Background Aetiological mechanisms underlying ethnic density associations with psychosis remain unclear. Aims To assess potential mechanisms underlying the observation that minority ethnic groups experience an increased risk of psychosis when living in neighbourhoods of lower own-group density. Method Multilevel analysis of nationally representative community-level data (from the Ethnic Minorities Psychiatric Illness Rates in the Community survey), which included the main minority ethnic groups living in England, and a White British group. Structured instruments assessed discrimination, chronic strains and social support. The Psychosis Screening Questionnaire ascertained psychotic experiences. Results For every ten percentage point reduction in own-group density, the relative odds of reporting psychotic experiences increased 1.07 times (95% CI 1.01–1.14, P = 0.03 (trend)) for the total minority ethnic sample. In general, people living in areas of lower own-group density experienced greater social adversity that was in turn associated with reporting psychotic experiences. Conclusions People resident in neighbourhoods of higher own-group density experience ‘buffering’ effects from the social risk factors for psychosis. PMID:22844021

  2. Cancer experiences and health-related quality of life among racial and ethnic minority survivors of young adult cancer: a mixed methods study.

    PubMed

    Munoz, Alexis R; Kaiser, Karen; Yanez, Betina; Victorson, David; Garcia, Sofia F; Snyder, Mallory A; Salsman, John M

    2016-12-01

    Young adult (YA) racial and ethnic minority survivors of cancer (diagnosed ages 18-39) experience significant disparities in health outcomes and survivorship compared to non-minorities of the same age. However, little is known about the survivorship experiences of this population. The purpose of this study is to explore the cancer experiences and health-related quality of life (HRQOL) among YA racial/ethnic minorities in an urban US city. Racial and ethnic minority YA cancer survivors (0 to 5 years posttreatment) were recruited from a comprehensive cancer center using a purposive sampling approach. Participants (n = 31) completed semi-structured interviews, the FACT-G (physical, emotional, social well-being) and the FACIT-Sp (spiritual well-being). Mixed methods data were evaluated using thematic analysis and analysis of covariance (ANCOVA). The majority of survivors were women (65 %), single (52 %), and Hispanic (42 %). Across interviews, the most common themes were the following: "changes in perspective," "emotional impacts," "received support," and "no psychosocial changes." Other themes varied by racial/ethnic subgroups, including "treatment effects" (Hispanics), "behavior changes" (Blacks), and "appreciation for life" (Asians). ANCOVAs (controlling for gender and ECOG performance status scores) revealed that race/ethnicity had a significant main effect on emotional (P = 0.05), but not physical, social, or spiritual HRQOL (P > 0.05). Our findings suggest that minority YA cancer survivors report complex positive and negative experiences. In spite of poor health outcomes, survivors report experiencing growth and positive change due to cancer. Variations in experiences and HRQOL highlight the importance of assessing cultural background to tailor survivorship care among YA racial and ethnic minorities.

  3. Allele-specific Characterization of Alanine: Glyoxylate Aminotransferase Variants Associated with Primary Hyperoxaluria

    PubMed Central

    Lage, Melissa D.; Pittman, Adrianne M. C.; Roncador, Alessandro; Cellini, Barbara; Tucker, Chandra L.

    2014-01-01

    Primary Hyperoxaluria Type 1 (PH1) is a rare autosomal recessive kidney stone disease caused by deficiency of the peroxisomal enzyme alanine: glyoxylate aminotransferase (AGT), which is involved in glyoxylate detoxification. Over 75 different missense mutations in AGT have been found associated with PH1. While some of the mutations have been found to affect enzyme activity, stability, and/or localization, approximately half of these mutations are completely uncharacterized. In this study, we sought to systematically characterize AGT missense mutations associated with PH1. To facilitate analysis, we used two high-throughput yeast-based assays: one that assesses AGT specific activity, and one that assesses protein stability. Approximately 30% of PH1-associated missense mutations are found in conjunction with a minor allele polymorphic variant, which can interact to elicit complex effects on protein stability and trafficking. To better understand this allele interaction, we functionally characterized each of 34 mutants on both the major (wild-type) and minor allele backgrounds, identifying mutations that synergize with the minor allele. We classify these mutants into four distinct categories depending on activity/stability results in the different alleles. Twelve mutants were found to display reduced activity in combination with the minor allele, compared with the major allele background. When mapped on the AGT dimer structure, these mutants reveal localized regions of the protein that appear particularly sensitive to interactions with the minor allele variant. While the majority of the deleterious effects on activity in the minor allele can be attributed to synergistic interaction affecting protein stability, we identify one mutation, E274D, that appears to specifically affect activity when in combination with the minor allele. PMID:24718375

  4. Structural Analysis of HMGD-DNA Complexes Reveal Influence of Intercalation on Sequence Selectivity and DNA Bending

    PubMed Central

    Churchill, Mair E.A.; Klass, Janet; Zoetewey, David L.

    2010-01-01

    The ubiquitous eukaryotic High-Mobility-Group-Box (HMGB) chromosomal proteins promote many chromatin-mediated cellular activities through their non-sequence-specific binding and bending of DNA. Minor groove DNA binding by the HMG box results in substantial DNA bending toward the major groove owing to electrostatic interactions, shape complementarity and DNA intercalation that occurs at two sites. Here, the structures of the complexes formed with DNA by a partially DNA intercalation-deficient mutant of Drosophila melanogaster HMGD have been determined by X-ray crystallography at a resolution of 2.85 Å. The six proteins and fifty base pairs of DNA in the crystal structure revealed a variety of bound conformations. All of the proteins bound in the minor groove, bridging DNA molecules, presumably because these DNA regions are easily deformed. The loss of the primary site of DNA intercalation decreased overall DNA bending and shape complementarity. However, DNA bending at the secondary site of intercalation was retained and most protein-DNA contacts were preserved. The mode of binding resembles the HMGB1-boxA-cisplatin-DNA complex, which also lacks a primary intercalating residue. This study provides new insights into the binding mechanisms used by HMG boxes to recognize varied DNA structures and sequences as well as modulate DNA structure and DNA bending. PMID:20800069

  5. Complexes of mismatched and complementary DNA with minor groove binders. Structures at nucleotide resolution via an improved hydroxyl radical cleavage methodology

    PubMed Central

    Bialonska, Dobroslawa; Song, Kenneth; Bolton, Philip H.

    2011-01-01

    Tumor cell lines can replicate faster than normal cells and many also have defective DNA repair pathways. This has lead to the investigation of the inhibition of DNA repair proteins as a means of therapeutic intervention. An alternative approach is to hide or mask damaged DNA from the repair systems. We have developed a protocol to investigate the structures of the complexes of damaged DNA with drug like molecules. Nucleotide resolution structural information can be obtained using an improved hydroxyl radical cleavage protocol. The use of a dTn tail increases the length of the smallest fragments of interest and allows efficient co-precipitation of the fragments with poly(A). The use of a fluorescent label, on the 5′ end of the dTn tail, in conjunction with modified cleavage reaction conditions, avoids the lifetime and other problems with 32P labeling. The structures of duplex DNAs containing AC and CC mismatches in the presence and absence of minor groove binders have been investigated as have those of the fully complementary DNA. The results indicate that the structural perturbations of the mismatches are localized, are sequence dependent and that the presence of a mismatch can alter the binding of drug like molecules. PMID:21893212

  6. Structure and soft magnetic properties of Fe-Si-B-P-Cu nanocrystalline alloys with minor Mn addition

    NASA Astrophysics Data System (ADS)

    Jia, Xingjie; Li, Yanhui; Wu, Licheng; Zhang, Wei

    2018-05-01

    Addition of minor Mn effectively improves the amorphous-forming ability and thermal stability of the Fe85Si2B8P4Cu1 alloy. With increasing the Mn content from 0 to 3 at.%, the critical thickness for amorphous formation and onset temperature of the primary crystallization increase from 14 μm and 659 K to 27 μm and 668 K, respectively. The fine nanocrystalline structure with α-Fe grains in size (D) of < 20 nm was obtained for the annealed amorphous alloys, which show excellent soft magnetic properties. The alloying of Mn reduces the coercivity (Hc) by decreasing the D value and widens the optimum annealing temperature range for obtaining low Hc, although the saturation magnetic flux density (Bs) is decreased slightly. The Fe83Mn2Si2B8P4Cu1 nanocrystalline alloy possesses fine structure with a D of ˜17.5 nm, and exhibits a high Bs of ˜1.75 T and a low Hc of ˜5.9 A/m. The mechanism related to the alloying effects on the structure and magnetic properties was discussed in term of the crystallization activation energy.

  7. In and out of the minor groove: interaction of an AT-rich DNA with the drug CD27

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Acosta-Reyes, Francisco J.; Dardonville, Christophe; Koning, Harry P. de

    New features of an antiprotozoal DNA minor-groove binding drug, which acts as a cross-linking agent, are presented. It also fills the minor groove of DNA completely and prevents the access of proteins. These features are also expected for other minor-groove binding drugs when associated with suitable DNA targets. The DNA of several pathogens is very rich in AT base pairs. Typical examples include the malaria parasite Plasmodium falciparum and the causative agents of trichomoniasis and trypanosomiases. This fact has prompted studies of drugs which interact with the minor groove of DNA, some of which are used in medical practice. Previousmore » studies have been performed almost exclusively with the AATT sequence. New features should be uncovered through the study of different DNA sequences. In this paper, the crystal structure of the complex of the DNA duplex d(AAAATTTT){sub 2} with the dicationic drug 4, 4′-bis(imidazolinylamino)diphenylamine (CD27) is presented. The drug binds to the minor groove of DNA as expected, but it shows two new features that have not previously been described: (i) the drugs protrude from the DNA and interact with neighbouring molecules, so that they may act as cross-linking agents, and (ii) the drugs completely cover the whole minor groove of DNA and displace bound water. Thus, they may prevent the access to DNA of proteins such as AT-hook proteins. These features are also expected for other minor-groove binding drugs when associated with all-AT DNA. These findings allow a better understanding of this family of compounds and will help in the development of new, more effective drugs. New data on the biological interaction of CD27 with the causative agent of trichomoniasis, Trichomonas vaginalis, are also reported.« less

  8. Dry minor mergers and size evolution of high-z compact massive early-type galaxies

    NASA Astrophysics Data System (ADS)

    Oogi, Taira; Habe, Asao

    2013-01-01

    Recent observations show evidence that high-z (z ˜ 2-3) early-type galaxies (ETGs) are more compact than those with comparable mass at z ˜ 0. Such size evolution is most likely explained by the `dry merger sceanario'. However, previous studies based on this scenario cannot consistently explain the properties of both high-z compact massive ETGs and local ETGs. We investigate the effect of multiple sequential dry minor mergers on the size evolution of compact massive ETGs. From an analysis of the Millennium Simulation Data Base, we show that such minor (stellar mass ratio M2/M1 < 1/4) mergers are extremely common during hierarchical structure formation. We perform N-body simulations of sequential minor mergers with parabolic and head-on orbits, including a dark matter component and a stellar component. Typical mass ratios of these minor mergers are 1/20 < M2/M1 ≤q 1/10. We show that sequential minor mergers of compact satellite galaxies are the most efficient at promoting size growth and decreasing the velocity dispersion of compact massive ETGs in our simulations. The change of stellar size and density of the merger remnants is consistent with recent observations. Furthermore, we construct the merger histories of candidates for high-z compact massive ETGs using the Millennium Simulation Data Base and estimate the size growth of the galaxies through the dry minor merger scenario. We can reproduce the mean size growth factor between z = 2 and z = 0, assuming the most efficient size growth obtained during sequential minor mergers in our simulations. However, we note that our numerical result is only valid for merger histories with typical mass ratios between 1/20 and 1/10 with parabolic and head-on orbits and that our most efficient size-growth efficiency is likely an upper limit.

  9. Do Low Income Youth of Color See "The Bigger Picture" When Discussing Type 2 Diabetes: A Qualitative Evaluation of a Public Health Literacy Campaign.

    PubMed

    Schillinger, Dean; Tran, Jessica; Fine, Sarah

    2018-04-24

    As Type 2 diabetes spikes among minority and low-income youth, there is an urgent need to tackle the drivers of this preventable disease. The Bigger Picture (TBP) is a counter-marketing campaign using youth-created, spoken-word public service announcements (PSAs) to reframe the epidemic as a socio-environmental phenomenon requiring communal action, civic engagement and norm change. We examined whether and how TBP PSAs advance health literacy among low-income, minority youth. We showed nine PSAs, asking individuals open-ended questions via questionnaire, then facilitating a focus group to reflect upon the PSAs. Questionnaire responses revealed a balance between individual vs. public health literacy. Some focused on individual responsibility and behaviors, while others described socio-environmental forces underlying risk. The focus group generated a preponderance of public health literacy responses, emphasizing future action. Striking sociopolitical themes emerged, reflecting tensions minority and low-income youth experience, such as entrapment vs. liberation. Our findings speak to the structural barriers and complexities underlying diabetes risk, and the ability of spoken word medium to make these challenges visible and motivate action. Delivering TBP content to promote interactive reflection has potential to change behavioral norms and build capacity to confront the social, economic and structural factors that influence behaviors.

  10. Organizational structure, leadership and readiness for change and the implementation of organizational cultural competence in addiction health services.

    PubMed

    Guerrero, Erick G; Kim, Ahraemi

    2013-10-01

    Increasing representation of racial and ethnic minorities in the health care system and on-going concerns about existing health disparities have pressured addiction health services programs to enhance their cultural competence. This study examines the extent to which organizational factors, such as structure, leadership and readiness for change contribute to the implementation of community, policy and staffing domains representing organizational cultural competence. Analysis of a randomly selected sample of 122 organizations located in primarily Latino and African American communities showed that programs with public funding and Medicaid reimbursement were positively associated with implementing policies and procedures, while leadership was associated with staff having greater knowledge of minority communities and developing a diverse workforce. Moreover, program climate was positively associated with staff knowledge of communities and having supportive policies and procedures, while programs with graduate staff and parent organizations were negatively associated with knowledge of and involvement in these communities. By investing in funding, leadership skills and a strategic climate, addiction health services programs may develop greater understanding and responsiveness of the service needs of minority communities. Implications for future research and program planning in an era of health care reform in the United States are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Thermal changes of the environment and their influence on reinforced concrete structures

    NASA Astrophysics Data System (ADS)

    Fojtik, R.; Cajka, R.

    2018-04-01

    The thermal expansion of concrete elements concerns both monolithic and prefabricated structures. Inappropriate design of dilation segments may cause minor but even larger failures. Critical environment factors are temperature-changing operations, such as unheated underground garages, where temperature fluctuations may occur depending on the exterior conditions. This paper numerically and experimentally analyses the thermal deformation of selected girders in the underground garages and the consequent structure failures, their causes, possible prevention and appropriate remediation.

  12. Preparative isolation and characterization of some minor impurities of astaxanthin by high-performance liquid chromatography.

    PubMed

    Rao, R Nageswara; Alvi, S Naseeruddin; Rao, B Nageswara

    2005-05-27

    A simple and rapid preparative high-performance liquid chromatography (HPLC) method has been developed to isolate and characterize some minor impurities of astaxanthin using a normal-phase Lichrosorb silica column with n-hexane-acetone-tetrahydrofuran (90:2:8, v/v/v) as mobile-phase and detection at 475 nm. The isolated impurities were characterized as astacene, dehydro astacene and apoastaxanthinal by UV-vis, ESI-MS, 1H and 13C NMR spectroscopy and the molecular structures were assigned. The impurities collected using the developed conditions were over 98% pure.

  13. The fluorescently responsive 3-(naphthalen-1-ylethynyl)-3-deaza-2'-deoxyguanosine discriminates cytidine via the DNA minor groove.

    PubMed

    Suzuki, Azusa; Yanagi, Masaki; Takeda, Takuya; Hudson, Robert H E; Saito, Yoshio

    2017-09-26

    A new environmentally responsive fluorescent nucleoside, 3-(naphthalen-1-ylethynyl)-3-deaza-2'-deoxyguanosine ( 3nz G), has been synthesized. The nucleoside, 3nz G, exhibited solvatochromic properties and when introduced into ODN probes it was able to recognize 2'-deoxycytidine in target strands by a distinct change in its emission wavelength through probing microenvironmental changes in the DNA minor groove. Thus, 3nz G has the potential for use as a fluorescent probe molecule for micro-structural studies of nucleic acids including the detection of single-base alterations in target DNA sequences.

  14. 75 FR 38831 - Repair Kalaupapa Dock Structure: Kalaupapa National Historical Park, Hawaii; Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-06

    ..., including minor to moderate effects on water quality, benthic resources, coral and essential fish habitats... required for the park's recycling program and other operations and activities). Originally the NPS planned...

  15. BLACK AND HISPANIC IMMIGRANTS' RESILIENCE AGAINST NEGATIVE ABILITY RACIAL STEREOTYPES AT SELECTIVE COLLEGES AND UNIVERSITIES IN THE UNITED STATES*

    PubMed

    Owens, Jayanti; Lynch, Scott M

    2012-10-01

    Stereotype threat is a widely supported theory for understanding the racial achievement gap in college grade performance. However, today's minority college students are increasingly of immigrant origins, and it is unclear whether two dispositional mechanisms that may increase susceptibility to stereotype threat are applicable to immigrants. We use survey data to examine whether and how negative ability stereotypes affect the grades of 1,865 first, second, and third generation or higher (domestic) minority students at 28 selective American colleges. Structural equation model results indicate that first generation immigrants are highly-resistant to both dispositional identity threat mechanisms we consider. Second generation immigrants experience only certain dispositional elements of identity threat. Drawing on research in social psychology, we suggest immigrants tend to resist stereotype threat in part due to the primacy of their immigrant identities and their connectedness to the opportunity structure of mainstream society.

  16. Petrology of Impact-Melt Rocks at the Chicxulub Multiring Basin, Yucatan, Mexico

    NASA Technical Reports Server (NTRS)

    Schuraytz, Benjamin C.; Sharpton, Virgil L.; Marin, Luis E.

    1994-01-01

    Compositions and textures of melt rocks from the upper part of the Chicxulub structure are typical of melt rocks at other large terrestrial impact structures. Apart from variably elevated iridium concentrations (less than 1.5 to 13.5 +/- 0.9 ppb) indicating nonuniform dissemination of a meteoritic component, bulk rock and phenocryst compositions imply that these melt rocks were derived exclusively from continental crust and platform-sediment target lithologies. Modest differences in bulk chemistry among samples from wells located approximately 40 km apart suggest minor variations in relative contributions of these target lithologies to the melts. Subtle variations in the compositions of early-formed pyroxene and plagioclase also support minor primary differences in chemistry between the melts. Evidence for pervasive hydrothermal alteration of the porous mesostasis includes albite, K-feldspar, quartz, epidote, chlorite, and other phyllosilicates, as well as siderophile element-enriched sulfides, suggesting the possibility that Chicxulub, like Sudbury, may host important ore deposits.

  17. Post-irradiation examinations of THERMHET composite fuels for transmutation

    NASA Astrophysics Data System (ADS)

    Noirot, J.; Desgranges, L.; Chauvin, N.; Georgenthum, V.

    2003-07-01

    The thermal behaviour of composite targets dedicated to minor actinide transmutation was studied using THERMHET (thermal behaviour of heterogeneous fuel) irradiation in the SILOE reactor. Three inert matrix fuel designs were tested (macro-mass, jingle and microdispersion) all with a MgAl 2O 4 spinel inert matrix and around 40% weight of UO 2 to simulate minor actinide inclusions. The post-irradiation examinations led to a new interpretation of the temperature measurement by thermocouples located in the central hole of the pellets. A major change in the micro-dispersed structure was detected. The examinations enabled us to understand the behaviour of the spinel during the different stages of irradiation. They revealed an amorphisation at low temperature and then a nano re-crystallisation at high temperature of the spinel in the micro-dispersed case. These results, together with those obtained in the MATINA irradiation of an equivalent structure, show the importance of the irradiation temperature on spinel behaviour.

  18. Parenting Practices as Predictors of Substance Use, Delinquency, and Aggression Among Urban Minority Youth: Moderating Effects of Family Structure and Gender

    PubMed Central

    Griffin, Kenneth W.; Botvin, Gilbert J.; Scheier, Lawrence M.; Diaz, Tracy; Miller, Nicole L.

    2014-01-01

    This study examined how parenting factors were associated with adolescent problem behaviors among urban minority youth and to what extent these relationships were moderated by family structure and gender. Sixth-grade students (N = 228) reported how often they use alcohol, smoke cigarettes, or engage in aggressive or delinquent behaviors; a parent or guardian reported their monitoring and other parenting practices. Findings indicated that boys and those from single-parent families engaged in the highest rates of problem behavior. More parental monitoring was associated with less delinquency overall, as well as less drinking in boys only. Eating family dinners together was associated with less aggression overall, as well as less delinquency in youth from single-parent families and in girls. Unsupervised time at home alone was associated with more smoking for girls only. Implications for prevention interventions are discussed. PMID:10860116

  19. BLACK AND HISPANIC IMMIGRANTS’ RESILIENCE AGAINST NEGATIVE ABILITY RACIAL STEREOTYPES AT SELECTIVE COLLEGES AND UNIVERSITIES IN THE UNITED STATES*

    PubMed Central

    Owens, Jayanti; Lynch, Scott M.

    2013-01-01

    Stereotype threat is a widely supported theory for understanding the racial achievement gap in college grade performance. However, today’s minority college students are increasingly of immigrant origins, and it is unclear whether two dispositional mechanisms that may increase susceptibility to stereotype threat are applicable to immigrants. We use survey data to examine whether and how negative ability stereotypes affect the grades of 1,865 first, second, and third generation or higher (domestic) minority students at 28 selective American colleges. Structural equation model results indicate that first generation immigrants are highly-resistant to both dispositional identity threat mechanisms we consider. Second generation immigrants experience only certain dispositional elements of identity threat. Drawing on research in social psychology, we suggest immigrants tend to resist stereotype threat in part due to the primacy of their immigrant identities and their connectedness to the opportunity structure of mainstream society. PMID:24077577

  20. Two years of gender identity service for minors: overrepresentation of natal girls with severe problems in adolescent development.

    PubMed

    Kaltiala-Heino, Riittakerttu; Sumia, Maria; Työläjärvi, Marja; Lindberg, Nina

    2015-01-01

    Increasing numbers of adolescents present in adolescent gender identity services, desiring sex reassignment (SR). The aim of this study is to describe the adolescent applicants for legal and medical sex reassignment during the first two years of adolescent gender identity team in Finland, in terms of sociodemographic, psychiatric and gender identity related factors and adolescent development. Structured quantitative retrospective chart review and qualitative analysis of case files of all adolescent SR applicants who entered the assessment by the end of 2013. The number of referrals exceeded expectations in light of epidemiological knowledge. Natal girls were markedly overrepresented among applicants. Severe psychopathology preceding onset of gender dysphoria was common. Autism spectrum problems were very common. The findings do not fit the commonly accepted image of a gender dysphoric minor. Treatment guidelines need to consider gender dysphoria in minors in the context of severe psychopathology and developmental difficulties.

  1. Residential segregation and birth weight among racial and ethnic minorities in the United States.

    PubMed

    Walton, Emily

    2009-12-01

    Racial and ethnic minorities are often residentially segregated from whites in urban settings, a fact which has important health consequences. Research on the relationship between residential segregation and health outcomes lacks national-level investigation of racial and ethnic minority groups other than African Americans. I use multilevel analyses to examine the associations of residential isolation and clustering with birth weight among Asian, black, and Latino Americans using data from the National Center for Health Statistics' Natality Files and the U.S. Census. Findings indicate that segregation has a negative effect on the likelihood of having a low birth weight baby among Asian Americans, suggesting a possible concentration of social and structural resources in highly-segregated communities. On the contrary, segregation marginally increases the odds of low birth weight among African Americans, but only in the presence of higher poverty rates. Segregation does not affect birth weight among Latino Americans.

  2. A New Stress-Based Model of Political Extremism

    PubMed Central

    Canetti-Nisim, Daphna; Halperin, Eran; Sharvit, Keren; Hobfoll, Stevan E.

    2011-01-01

    Does exposure to terrorism lead to hostility toward minorities? Drawing on theories from clinical and social psychology, we propose a stress-based model of political extremism in which psychological distress—which is largely overlooked in political scholarship—and threat perceptions mediate the relationship between exposure to terrorism and attitudes toward minorities. To test the model, a representative sample of 469 Israeli Jewish respondents was interviewed on three occasions at six-month intervals. Structural Equation Modeling indicated that exposure to terrorism predicted psychological distress (t1), which predicted perceived threat from Palestinian citizens of Israel (t2), which, in turn, predicted exclusionist attitudes toward Palestinian citizens of Israel (t3). These findings provide solid evidence and a mechanism for the hypothesis that terrorism introduces nondemocratic attitudes threatening minority rights. It suggests that psychological distress plays an important role in political decision making and should be incorporated in models drawing upon political psychology. PMID:22140275

  3. Studies on the Growth Effects of the Canaline-Urea Cycle Amino Acids with Lemna minor L. 1

    PubMed Central

    Rosenthal, Gerald A.; Gulati, Dushyant K.; Sabharwal, P. S.

    1975-01-01

    The aquatic microphyte, Lemna minor L., was utilized to assess the relative toxicity and general growth effects of canavanine, canaline, ureidohomoserine (UHS), and canavaninosuccinate (CSA). These amino acids are constituents of the canaline-urea cycle and structural analogues of the ornithine-urea cycle amino acids. Comparative growth studies with L. minor revealed that the canaline-urea cycle amino acids are potent antimetabolites. With the exception of CSA, they are extremely toxic at a concentration of 5 μm. Over a concentration range of 1 to 4 μm, canavanine is the most growth-inhibiting of the canaline-urea cycle amino acids. At or above 5 μm, canavanine and canaline possess comparable toxicity. UHS is less growth-inhibiting than canavanine or canaline, and CSA is the least toxic of the canaline-urea cycle intermediates. PMID:16659316

  4. The influence of acculturation on substance use behaviors among Latina sexual minority women: the mediating role of discrimination.

    PubMed

    Matthews, Alicia; Li, Chien-Ching; Aranda, Frances; Torres, Lourdes; Vargas, Maria; Conrad, Megan

    2014-12-01

    A large body of work has demonstrated that sexual minority women have elevated rates of substance use morbidity, as compared with heterosexual women, and that this might be especially true for women of color. This study examines the influence of acculturation and discrimination on substance use among Latina sexual minority women. Data were collected from 2007 to 2008 as part of a larger community-based survey in the greater Chicago area. Scales measured discrimination, acculturation, and substance use. Structural equation modeling validated scales and examined their relationships, which were further described via mediation analysis. Increased acculturation leads to substance use and this relationship is partially mediated by discrimination (Sobel test = 2.10; p < .05). CONCLUSIONS/IMPORTANCE: Implications of these findings and directions for future research are discussed. Funding was provided by several women's and public health organizations.

  5. Examining the psychology of working theory: Decent work among sexual minorities.

    PubMed

    Douglass, Richard P; Velez, Brandon L; Conlin, Sarah E; Duffy, Ryan D; England, Jessica W

    2017-10-01

    Research has found heterosexist discrimination negatively relates to vocational outcomes among lesbian, gay, and bisexual (LGB) people, but no known study has examined how heterosexist discrimination relates to the attainment of decent work. Building from the Psychology of Working Theory, which proposes that specific forms of marginalization coupled with economic constraints limit a person's ability to secure decent work, the present study examined theoretically hypothesized pathways to decent work among a sample of employed sexual minority adults. Heterosexist discrimination and social class were examined as direct predictors of decent work, and indirect links were examined via work volition and career adaptability. Among our sample of 218 sexual minority people, structural equation modeling results suggested heterosexist discrimination and social class directly-and indirectly through work volition-predicted decent work. Practical implications and directions for future research are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Minor emergency clinic: key to the future of successful hospitals.

    PubMed

    Chawla, S; Kathawala, Y; Elmuti, D

    1992-01-01

    This project set out to determine whether there is a relationship between the minor emergency facility an individual uses and their choice of a hospital for in-patient care. In studying this relationship, the factors that are important to persons choosing a clinic or hospital facility, as well as the influence of a physician, were also identified. A structured, undisguised telephone survey was used for interviewing a randomly selected sample population of 189 San Angelo residents. Analysis of the survey data indicated that dependency does exist between minor emergency clinic use and the hospital chosen for in-patient care. The results of this study also suggested that hospitals' marketing strategy should shift the emphasis of their advertising from the hospital itself to their physician association and clinics. In addition, a number of other interesting observations concerning the relative importance of various medical factors to the participants was also explored.

  7. Systematic mapping review of the factors influencing dietary behaviour in ethnic minority groups living in Europe: a DEDIPAC study.

    PubMed

    Osei-Kwasi, Hibbah Araba; Nicolaou, Mary; Powell, Katie; Terragni, Laura; Maes, Lea; Stronks, Karien; Lien, Nanna; Holdsworth, Michelle

    2016-07-28

    Europe has a growing population of ethnic minority groups whose dietary behaviours are potentially of public health concern. To promote healthier diets, the factors driving dietary behaviours need to be understood. This review mapped the broad range of factors influencing dietary behaviour among ethnic minority groups living in Europe, in order to identify research gaps in the literature to guide future research. A systematic mapping review was conducted (protocol registered with PROSPERO 2014: CRD42014013549). Nine databases were searched for quantitative and qualitative primary research published between 1999 and 2014. Ethnic minority groups were defined as immigrants/populations of immigrant background from low and middle income countries, population groups from former Eastern Bloc countries and minority indigenous populations. In synthesizing the findings, all factors were sorted and structured into emerging clusters according to how they were seen to relate to each other. Thirty-seven of 2965 studies met the inclusion criteria (n = 18 quantitative; n = 19 qualitative). Most studies were conducted in Northern Europe and were limited to specific European countries, and focused on a selected number of ethnic minority groups, predominantly among populations of South Asian origin. The 63 factors influencing dietary behaviour that emerged were sorted into seven clusters: social and cultural environment (16 factors), food beliefs and perceptions (11 factors), psychosocial (9 factors), social and material resources (5 factors), accessibility of food (10 factors), migration context (7 factors), and the body (5 factors). This review identified a broad range of factors and clusters influencing dietary behaviour among ethnic minority groups. Gaps in the literature identified a need for researchers to explore the underlying mechanisms that shape dietary behaviours, which can be gleaned from more holistic, systems-based studies exploring relationships between factors and clusters. The dominance of studies exploring 'differences' between ethnic minority groups and the majority population in terms of the socio-cultural environment and food beliefs suggests a need for research exploring 'similarities'. The evidence from this review will feed into developing a framework for the study of factors influencing dietary behaviours in ethnic minority groups in Europe.

  8. Medical decision-making in children and adolescents: developmental and neuroscientific aspects.

    PubMed

    Grootens-Wiegers, Petronella; Hein, Irma M; van den Broek, Jos M; de Vries, Martine C

    2017-05-08

    Various international laws and guidelines stress the importance of respecting the developing autonomy of children and involving minors in decision-making regarding treatment and research participation. However, no universal agreement exists as to at what age minors should be deemed decision-making competent. Minors of the same age may show different levels of maturity. In addition, patients deemed rational conversation-partners as a child can suddenly become noncompliant as an adolescent. Age, context and development all play a role in decision-making competence. In this article we adopt a perspective on competence that specifically focuses on the impact of brain development on the child's decision-making process. We believe that the discussion on decision-making competence of minors can greatly benefit from a multidisciplinary approach. We adopted such an approach in order to contribute to the understanding on how to deal with children in decision-making situations. Evidence emerging from neuroscience research concerning the developing brain structures in minors is combined with insights from various other fields, such as psychology, decision-making science and ethics. Four capacities have been described that are required for (medical) decision-making: (1) communicating a choice; (2) understanding; (3) reasoning; and (4) appreciation. Each capacity is related to a number of specific skills and abilities that need to be sufficiently developed to support the capacity. Based on this approach it can be concluded that at the age of 12 children can have the capacity to be decision-making competent. However, this age coincides with the onset of adolescence. Early development of the brain's reward system combined with late development of the control system diminishes decision-making competence in adolescents in specific contexts. We conclude that even adolescents possessing capacities required for decision-making, may need support of facilitating environmental factors. This paper intends to offer insight in neuroscientific mechanisms underlying the medical decision-making capacities in minors and to stimulate practices for optimal involvement of minors. Developing minors become increasingly capable of decision-making, but the neurobiological development in adolescence affects competence in specific contexts. Adequate support should be offered in order to create a context in which minors can make competently make decisions.

  9. MD simulation study of the diffusion and local structure of n-alkanes in liquid and supercritical methanol at infinite dilution.

    PubMed

    Feng, Huajie; Gao, Wei; Su, Li; Sun, Zhenfan; Chen, Liuping

    2017-06-01

    The diffusion coefficients of 14 n-alkanes (ranging from methane to n-tetradecane) in liquid and supercritical methanol at infinite dilution (at a pressure of 10.5 MPa and at temperatures of 299 K and 515 K) were deduced via molecular dynamics simulations. Values for the radial distribution function, coordination number, and number of hydrogen bonds were then calculated to explore the local structure of each fluid. The flexibility of the n-alkane (as characterized by the computed dihedral distribution, end-to-end distance, and radius of gyration) was found to be a major influence and hydrogen bonding to be a minor influence on the local structure. Hydrogen bonding reduces the flexibility of the n-alkane, whereas increasing the temperature enhances its flexibility, with temperature having a greater effect than hydrogen bonding on flexibility. Graphical abstract The flexibility of the alkane is a major influence and the hydrogen bonding is a minor influence on the first solvation shell; the coordination numbers of long-chain n-alkanes in the first solvation shell are rather low.

  10. Electronic structure of lanthanide scandates

    NASA Astrophysics Data System (ADS)

    Mizzi, Christopher A.; Koirala, Pratik; Marks, Laurence D.

    2018-02-01

    X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, and density functional theory calculations were used to study the electronic structure of three lanthanide scandates: GdSc O3,TbSc O3 , and DySc O3 . X-ray photoelectron spectra simulated from first-principles calculations using a combination of on-site hybrid and GGA +U methods were found to be in good agreement with experimental x-ray photoelectron spectra. The hybrid method was used to model the ground state electronic structure and the GGA +U method accounted for the shift of valence state energies due to photoelectron emission via a Slater-Janak transition state approach. From these results, the lanthanide scandate valence bands were determined to be composed of Ln 4 f ,O 2 p , and Sc 3 d states, in agreement with previous work. However, contrary to previous work the minority Ln 4 f states were found to be located closer to, and in some cases at, the valence band maximum. This suggests that minority Ln 4 f electrons may play a larger role in lanthanide scandate properties than previously thought.

  11. Does TATA matter? A structural exploration of the selectivity determinants in its complexes with TATA box-binding protein.

    PubMed Central

    Pastor, N; Pardo, L; Weinstein, H

    1997-01-01

    The binding of the TATA box-binding protein (TBP) to a TATA sequence in DNA is essential for eukaryotic basal transcription. TBP binds in the minor groove of DNA, causing a large distortion of the DNA helix. Given the apparent stereochemical equivalence of AT and TA basepairs in the minor groove, DNA deformability must play a significant role in binding site selection, because not all AT-rich sequences are bound effectively by TBP. To gain insight into the precise role that the properties of the TATA sequence have in determining the specificity of the DNA substrates of TBP, the solution structure and dynamics of seven DNA dodecamers have been studied by using molecular dynamics simulations. The analysis of the structural properties of basepair steps in these TATA sequences suggests a reason for the preference for alternating pyrimidine-purine (YR) sequences, but indicates that these properties cannot be the sole determinant of the sequence specificity of TBP. Rather, recognition depends on the interplay between the inherent deformability of the DNA and steric complementarity at the molecular interface. Images FIGURE 2 PMID:9251783

  12. A possible molecular basis for photoprotection in the minor antenna proteins of plants.

    PubMed

    Fox, Kieran F; Ünlü, Caner; Balevičius, Vytautas; Ramdour, Baboo Narottamsing; Kern, Carina; Pan, Xiaowei; Li, Mei; van Amerongen, Herbert; Duffy, Christopher D P

    2018-07-01

    The bioenergetics of light-harvesting by photosynthetic antenna proteins in higher plants is well understood. However, investigation into the regulatory non-photochemical quenching (NPQ) mechanism, which dissipates excess energy in high light, has led to several conflicting models. It is generally accepted that the major photosystem II antenna protein, LHCII, is the site of NPQ, although the minor antenna complexes (CP24/26/29) are also proposed as alternative/additional NPQ sites. LHCII crystals were shown to exhibit the short excitation lifetime and several spectral signatures of the quenched state. Subsequent structure-based models showed that this quenching could be explained by slow energy trapping by the carotenoids, in line with one of the proposed models. Using Fluorescence Lifetime Imaging Microscopy (FLIM) we show that the crystal structure of CP29 corresponds to a strongly quenched conformation. Using a structure-based theoretical model we show that this quenching may be explained by the same slow, carotenoid-mediated quenching mechanism present in LHCII crystals. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Interaction of aldolase with actin-containing filaments. Structural studies.

    PubMed Central

    Stewart, M; Morton, D J; Clarke, F M

    1980-01-01

    Electron micrographs of the paracrystals formed when fructose bisphosphate aldolase (EC 4.1.2.13) is added to actin-containing filaments were analysed by computer methods so that ultrastructural changes could be correlated with the various stoicheiometries of binding determined in the preceding paper [Walsh, Winzor, Clarke, Masters & Morton (1980) Biochem. J. 186, 89-98]. Paracrystals formed with aldolase and either F-actin or F-actin-tropomyosin have a single light transverse band every 38 nm, which is due to aldolase molecules cross-linking the filaments. In contrast, the paracrystals formed between aldolase and F-actin-tropomyosin-troponin filaments show two transverse bands every 38 nm: a major band, interpreted as aldolase binding to troponin, and a minor band, interpreted as aldolase cross-linking the filaments. The intensity of the minor band varies with Ca2+ concentration, being greatest when the Ca2+ concentration is low. A model for the different paracrystal structures which relates the various patterns and binding stoicheiometries to structural changes in the actin-containing filaments is proposed. Images PLATE 1 PMID:6892771

  14. Deletion of pilA, a Minor Pilin-Like Gene, from Xanthomonas citri subsp. citri Influences Bacterial Physiology and Pathogenesis.

    PubMed

    Petrocelli, Silvana; Arana, Maite R; Cabrini, Marcela N; Casabuono, Adriana C; Moyano, Laura; Beltramino, Matías; Moreira, Leandro M; Couto, Alicia S; Orellano, Elena G

    2016-12-01

    Type IV pili (Tfp) are widely distributed adhesins of bacterial surfaces. In plant pathogenic bacteria, Tfp are involved in host colonization and pathogenesis. Xanthomonas citri subsp. citri (Xcc) is the phytopathogen responsible for citrus canker disease. In this work, three Tfp structural genes, fimA, fimA1, and pilA from Xcc were studied. A pilA mutant strain from Xcc (XccΔpilA) was constructed and differences in physiological features, such as motilities, adhesion, and biofilm formation, were observed. A structural study of the purified Tfp fractions from Xcc wild-type and Xcc∆pilA showed that pilins are glycosylated in both strains and that FimA and FimA1 are the main structural components of the pili. Furthermore, smaller lesion symptoms and reduced bacterial growth were produced by Xcc∆pilA in orange plants compared to the wild-type strain. These results indicate that the minor pilin-like gene, pilA, is involved in Tfp performance during the infection process.

  15. Intimate Partner Violence and Its Health Impact on Disproportionately Affected Populations, Including Minorities and Impoverished Groups

    PubMed Central

    Hayashi, Hitomi; Campbell, Jacquelyn C.

    2015-01-01

    Abstract In the United States, intimate partner violence (IPV) against women disproportionately affects ethnic minorities. Further, disparities related to socioeconomic and foreign-born status impact the adverse physical and mental health outcomes as a result of IPV, further exacerbating these health consequences. This article reviews 36 U.S. studies on the physical (e.g., multiple injuries, disordered eating patterns), mental (e.g., depression, post-traumatic stress disorder), and sexual and reproductive health conditions (e.g., HIV/STIs, unintended pregnancy) resulting from IPV victimization among ethnic minority (i.e., Black/African American, Hispanic/Latina, Native American/Alaska Native, Asian American) women, some of whom are immigrants. Most studies either did not have a sufficient sample size of ethnic minority women or did not use adequate statistical techniques to examine differences among different racial/ethnic groups. Few studies focused on Native American/Alaska Native and immigrant ethnic minority women and many of the intra-ethnic group studies have confounded race/ethnicity with income and other social determinants of health. Nonetheless, of the available data, there is evidence of health inequities associated with both minority ethnicity and IPV. To appropriately respond to the health needs of these groups of women, it is necessary to consider social, cultural, structural, and political barriers (e.g., medical mistrust, historical racism and trauma, perceived discrimination, immigration status) to patient–provider communication and help-seeking behaviors related to IPV, which can influence health outcomes. This comprehensive approach will mitigate the racial/ethnic and socioeconomic disparities related to IPV and associated health outcomes and behaviors. PMID:25551432

  16. 'Flying below the radar': a qualitative study of minority experience and management of discrimination in academic medicine.

    PubMed

    Carr, Phyllis L; Palepu, Anita; Szalacha, Laura; Caswell, Cheryl; Inui, Thomas

    2007-06-01

    This paper aims to give voice to the lived experience of faculty members who have encountered racial or ethnic discrimination in the course of their academic careers. It looks at how they describe the environment for minorities, how they manage discrimination and what institutions and majority-member faculty can do to improve medical academe for minority members. Qualitative techniques were used for semi-structured, in-depth individual telephone interviews, which were audiotaped, transcribed and analysed by reviewers. Themes expressed by multiple faculty members were studied for patterns of connection and grouped into broader categories. A description of the faculty sample is provided, in which respondents ranked the importance of discrimination in hindering academic advancement and used Likert scales to evaluate effects of discrimination. The sample was drawn from 12 of 24 academic medical centres in the National Faculty Survey and included 18 minority-member faculty staff stratified by gender, rank and degree who had experienced, or possibly experienced, work-related discrimination. Minority faculty described the need to be strongly self-reliant, repeatedly prove themselves, develop strong supports and acquire a wide range of academic skills to succeed. Suggested responses to discrimination were to be cautious, level-headed and informed. Confronting discriminatory actions by sitting down with colleagues and raising the level of awareness were important methods of dealing with such situations. Academic medical centres may need to make greater efforts to support minority faculty and improve understanding of the challenges confronting such faculty in order to prevent the loss and/or under-utilisation of important talent.

  17. A multilevel health promotion intervention in minority-owned workplaces

    PubMed Central

    Bowen, Deborah J.; Briant, Katherine J.; Harris, Jeffrey; Hannon, Peggy; Buchwald, Dedra

    2015-01-01

    Introduction Changing health behaviors and health-related environments is important in reducing chronic disease. Minority workplaces are potential venues to provide regular, effective health promotion opportunities to underserved individuals. The purpose of this study was to test the feasibility of changing workplace policy, programs, and practices in minority-owned workplaces. Methods Four minority Native American-owned businesses were recruited to participate in this study. The intervention was a set of recommended standards and guidelines gleaned from the US Preventive Task Force and The Community Guide relevant to workplaces. Each workplace selected between 4 and 6 target areas to improve over the year-long intervention period. The evaluation tool was a semi-structured survey conducted at baseline and at one-year follow-up, with workplace staff responsible for benefits and services to employees. Feasibility was evaluated by assessing the likelihood that the workplaces implemented health promotion activities in the year-long intervention. Results Several practices and policies changed significantly during the intervention in the four workplaces, including coverage for nicotine replacement therapy (NRT), elimination of out of pocket costs for screening and tobacco cessation, accountability systems for providers, posted stair use, cessation line availability that included NRT, offering weight loss programs, offering physical activity programs, and conducting targeted communication programs about health promotion. Other practices and polices changed in the expected direction, but were not significant. Conclusion Changing workplace programs, practices, and policies is feasible in minority workplaces, with support and tools provided by outside organizations. These findings could drive a full-scale test of the intervention in minority businesses in order to improve the health of disadvantaged workers. PMID:26693135

  18. Intimate Partner Violence and its Health Impact on Ethnic Minority Women [corrected].

    PubMed

    Stockman, Jamila K; Hayashi, Hitomi; Campbell, Jacquelyn C

    2015-01-01

    In the United States, intimate partner violence (IPV) against women disproportionately affects ethnic minorities. Further, disparities related to socioeconomic and foreign-born status impact the adverse physical and mental health outcomes as a result of IPV, further exacerbating these health consequences. This article reviews 36 U.S. studies on the physical (e.g., multiple injuries, disordered eating patterns), mental (e.g., depression, post-traumatic stress disorder), and sexual and reproductive health conditions (e.g., HIV/STIs, unintended pregnancy) resulting from IPV victimization among ethnic minority (i.e., Black/African American, Hispanic/Latina, Native American/Alaska Native, Asian American) women, some of whom are immigrants. Most studies either did not have a sufficient sample size of ethnic minority women or did not use adequate statistical techniques to examine differences among different racial/ethnic groups. Few studies focused on Native American/Alaska Native and immigrant ethnic minority women and many of the intra-ethnic group studies have confounded race/ethnicity with income and other social determinants of health. Nonetheless, of the available data, there is evidence of health inequities associated with both minority ethnicity and IPV. To appropriately respond to the health needs of these groups of women, it is necessary to consider social, cultural, structural, and political barriers (e.g., medical mistrust, historical racism and trauma, perceived discrimination, immigration status) to patient-provider communication and help-seeking behaviors related to IPV, which can influence health outcomes. This comprehensive approach will mitigate the racial/ethnic and socioeconomic disparities related to IPV and associated health outcomes and behaviors.

  19. The 'biliterate' ballot controversy: language acquisition and cultural shift among immigrants.

    PubMed

    Loo, C M

    1985-01-01

    This US study tested the validity of assumptions made regarding multilingual electoral ballot provisions. Rationale for language assistance was found to exist on the basis of number and proportion of recent immigrants, proportion of foreign born, lag of biliterate skill behind bilingual ability, linguistic differences between the Chinese language and English, and the discriminatory structure of the labor market. In California, where close to 1/2 the population is an ethnic minority, the issue is particularly relevant. Bilingual advocates view English-only advocates as "un-American" on legal and ideological grounds, while English-only advocates consider it "un-American" to be non-English speaking. In addition to census data and the existing literature, this study relies on the structured interview survey data of a representative sample of the Chinese adult population of San Francisco's Chinatown. 2/3 of the immigrants believed an immigrant should make some cultural changes, and 1/2 of the immigrants had done so. Data failed to support the claim that immigrants are uninformed that English is necessary for sociopolitical participation. Their more recent pattern of immigration, the linguistic differences between Asian languages and the English language, and structural constraints of US society make successive language acquisition difficult for Chinese migrant adults. Policy recommendations include: 1) changing language assistance criteria in the electoral process, 2) adding Vietnamese as a single language minority, 3) not considering Asian language minorities as 1 generic category, 4) justifying electoral assistance on several grounds, 5) disseminating data bearing directly on misguided assumptions related to language and cultural shift factors, and 6) renaming the "bilingual ballots" to "biliterate ballots."

  20. Structure of the Minor Pseudopilin EpsH From the Type 2 Secretion System of Vibrio Cholerae

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yanez, M.E.; Korotkov, K.V.; Abendroth, J.

    2009-05-28

    Many Gram-negative bacteria use the multi-protein type II secretion system (T2SS) to selectively translocate virulence factors from the periplasmic space into the extracellular environment. In Vibrio cholerae the T2SS is called the extracellular protein secretion (Eps) system, which translocates cholera toxin and several enzymes in their folded state across the outer membrane. Five proteins of the T2SS, the pseudopilins, are thought to assemble into a pseudopilus, which may control the outer membrane pore EpsD, and participate in the active export of proteins in a 'piston-like' manner. We report here the 2.0 {angstrom} resolution crystal structure of an N-terminally truncated variantmore » of EpsH, a minor pseudopilin from Vibrio cholerae. While EpsH maintains an N-terminal {alpha}-helix and C-terminal {beta}-sheet consistent with the type 4a pilin fold, structural comparisons reveal major differences between the minor pseudopilin EpsH and the major pseudopilin GspG from Klebsiella oxytoca: EpsH contains a large {beta}-sheet in the variable domain, where GspG contains an {alpha}-helix. Most importantly, EpsH contains at its surface a hydrophobic crevice between its variable and conserved {beta}-sheets, wherein a majority of the conserved residues within the EpsH family are clustered. In a tentative model of a T2SS pseudopilus with EpsH at its tip, the conserved crevice faces away from the helix axis. This conserved surface region may be critical for interacting with other proteins from the T2SS machinery.« less

  1. Dynamics of the GB3 loop regions from MD simulation: how much of it is real?

    PubMed

    Li, Tong; Jing, Qingqing; Yao, Lishan

    2011-04-07

    A total of 1.1 μs of molecular dynamics (MD) simulations were performed to study the structure and dynamics of protein GB3. The simulation motional amplitude of the loop regions is generally overestimated in comparison with the experimental backbone N-H order parameters S(2). Two-state behavior is observed for several residues in these regions, with the minor state population in the range of 3-13%. Further inspection suggests that the (φ, ψ) dihedral angles of the minor states deviate from the GB3 experimental values, implying the existence of nonnative states. After fitting the MD trajectories of these residues to the NMR RDCs, the minor state populations are significantly reduced by at least 80%, suggesting that MD simulations are strongly biased toward the minor states, thus overestimating the dynamics of the loop regions. The optimized trajectories produce intra, sequential H(N)-H(α) RDCs and intra (3)J(HNHα) that are not included in the trajectories fitting for these residues that are closer to the experimental data. Unlike GB3, 0.55 μs MD simulations of protein ubiquitin do not show distinctive minor states, and the derived NMR order parameters are better converged. Our findings indicate that the artifacts of the simulations depend on the specific system studied and that one should be cautious interpreting the enhanced dihedral dynamics from long MD simulations.

  2. Who decides? The decision-making process of juvenile judges concerning minors with mental disorders.

    PubMed

    Cappon, Leen

    2016-01-01

    Previous research on juvenile judges' decision-making process has neglected the role of the different actors involved in judicial procedures. The decision can be considered as a result of information exchange between the different actors involved. The process of making a decision is equally important as the decision itself, especially when the decision considers minors with mental disorders. The presence and the type of interaction determine the information available to the juvenile judges to make their final decision. The overall aim of this study is to gain insight into the role of all actors, including the juvenile judge, in the juvenile judge's decision-making process in cases relating to minors with mental disorders. Semi-structured interviews were carried out with professional actors (n=32), minors (n=31) and parents (n=17). The findings indicated that the judge's decision is overall the result of an interaction between the juvenile judge, the social services investigator and the youth psychiatrist. The other professional actors, the minors and the parents had only a limited role in the decision-making process. The research concludes that the judge's decision-making process should be based on dialogue, and requires enhanced collaboration between the juvenile court and youth psychiatrists from mental health services. Future decision-making research should pay more attention to the interactions of the actors that guide a juvenile judge's decision. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Ethnic Swedish parents' experiences of minority ethnic nurses' cultural competence in Swedish paediatric care.

    PubMed

    Tavallali, Azar G; Kabir, Zarina Nahar; Jirwe, Maria

    2014-06-01

    Sweden has a population of a little more than 9.4 million. The rapid growth of immigration in Sweden has resulted in an increased number of minority ethnic patients and minority ethnic nurses in the Swedish healthcare system. This also applies to paediatric care. The purpose of this study was to explore how parents with ethnic Swedish backgrounds experience minority ethnic nurses' cultural competence and the care the nurses provide in a Swedish paediatric care context. This exploratory qualitative study is of 14 parents with an ethnic Swedish background whose child was in a ward at a children's hospital in Stockholm County Council. Data were collected using semi-structured interviews to identify parents' perceptions and experiences of minority ethnic nurses' cultural competence. The interviews were analysed by qualitative content analysis. The analyses of the interviews led to four main categories: influence of nurses' ethnicity; significance of cross-cultural communication; cross-cultural skills; and the importance of nursing education. Nurses' ethnicity did not have much impact on parents' satisfaction with their child's care. The parents attached importance to nurses' language skills and to their adaptation and awareness of Swedish culture. They also attached weight to nurses' professional knowledge and personal attributes. The role of nursing education to increase nurses' cultural awareness was highlighted too. © 2013 Nordic College of Caring Science.

  4. Soldering Characteristics and Mechanical Properties of Sn-1.0Ag-0.5Cu Solder with Minor Aluminum Addition

    PubMed Central

    Leong, Yee Mei; Haseeb, A.S.M.A.

    2016-01-01

    Driven by the trends towards miniaturization in lead free electronic products, researchers are putting immense efforts to improve the properties and reliabilities of Sn based solders. Recently, much interest has been shown on low silver (Ag) content solder SAC105 (Sn-1.0Ag-0.5Cu) because of economic reasons and improvement of impact resistance as compared to SAC305 (Sn-3.0Ag-0.5Cu. The present work investigates the effect of minor aluminum (Al) addition (0.1–0.5 wt.%) to SAC105 on the interfacial structure between solder and copper substrate during reflow. The addition of minor Al promoted formation of small, equiaxed Cu-Al particle, which are identified as Cu3Al2. Cu3Al2 resided at the near surface/edges of the solder and exhibited higher hardness and modulus. Results show that the minor addition of Al does not alter the morphology of the interfacial intermetallic compounds, but they substantially suppress the growth of the interfacial Cu6Sn5 intermetallic compound (IMC) after reflow. During isothermal aging, minor alloying Al has reduced the thickness of interfacial Cu6Sn5 IMC but has no significant effect on the thickness of Cu3Sn. It is suggested that of atoms of Al exert their influence by hindering the flow of reacting species at the interface. PMID:28773645

  5. Soldering Characteristics and Mechanical Properties of Sn-1.0Ag-0.5Cu Solder with Minor Aluminum Addition.

    PubMed

    Leong, Yee Mei; Haseeb, A S M A

    2016-06-28

    Driven by the trends towards miniaturization in lead free electronic products, researchers are putting immense efforts to improve the properties and reliabilities of Sn based solders. Recently, much interest has been shown on low silver (Ag) content solder SAC105 (Sn-1.0Ag-0.5Cu) because of economic reasons and improvement of impact resistance as compared to SAC305 (Sn-3.0Ag-0.5Cu. The present work investigates the effect of minor aluminum (Al) addition (0.1-0.5 wt.%) to SAC105 on the interfacial structure between solder and copper substrate during reflow. The addition of minor Al promoted formation of small, equiaxed Cu-Al particle, which are identified as Cu₃Al₂. Cu₃Al₂ resided at the near surface/edges of the solder and exhibited higher hardness and modulus. Results show that the minor addition of Al does not alter the morphology of the interfacial intermetallic compounds, but they substantially suppress the growth of the interfacial Cu₆Sn₅ intermetallic compound (IMC) after reflow. During isothermal aging, minor alloying Al has reduced the thickness of interfacial Cu₆Sn₅ IMC but has no significant effect on the thickness of Cu₃Sn. It is suggested that of atoms of Al exert their influence by hindering the flow of reacting species at the interface.

  6. Knowledge-Based Elastic Potentials for Docking Drugs or Proteins with Nucleic Acids

    PubMed Central

    Ge, Wei; Schneider, Bohdan; Olson, Wilma K.

    2005-01-01

    Elastic ellipsoidal functions defined by the observed hydration patterns around the DNA bases provide a new basis for measuring the recognition of ligands in the grooves of double-helical structures. Here a set of knowledge-based potentials suitable for quantitative description of such behavior is extracted from the observed positions of water molecules and amino acid atoms that form hydrogen bonds with the nitrogenous bases in high resolution crystal structures. Energies based on the displacement of hydrogen-bonding sites on drugs in DNA-crystal complexes relative to the preferred locations of water binding around the heterocyclic bases are low, pointing to the reliability of the potentials and the apparent displacement of water molecules by drug atoms in these structures. The validity of the energy functions has been further examined in a series of sequence substitution studies based on the structures of DNA bound to polyamides that have been designed to recognize the minor-groove edges of Watson-Crick basepairs. The higher energies of binding to incorrect sequences superimposed (without conformational adjustment or displacement of polyamide ligands) on observed high resolution structures confirm the hypothesis that the drug subunits associate with specific DNA bases. The knowledge-based functions also account satisfactorily for the measured free energies of DNA-polyamide association in solution and the observed sites of polyamide binding on nucleosomal DNA. The computations are generally consistent with mechanisms by which minor-groove binding ligands are thought to recognize DNA basepairs. The calculations suggest that the asymmetric distributions of hydrogen-bond-forming atoms on the minor-groove edge of the basepairs may underlie ligand discrimination of G·C from C·G pairs, in addition to the commonly believed role of steric hindrance. The analysis of polyamide-bound nucleosomal structures reveals other discrepancies in the expected chemical design, including unexpected contacts to DNA and modified basepair targets of some ligands. The ellipsoidal potentials thus appear promising as a mathematical tool for the study of drug- and protein-DNA interactions and for gaining new insights into DNA-binding mechanisms. PMID:15501936

  7. Diversity within the Profession. Part Two: Initiatives Promoting Diversity.

    ERIC Educational Resources Information Center

    Spafford, Marlee M.; Sharma, Neepun; Nygaard, Vicki L.; Kahlou, Christina

    2002-01-01

    Examines the literature on minority experiences in optometry and other health professions, describing programs geared either toward increasing diversity or facilitating acceptance of diversity within the optometric profession, including affirmative action and other institutional support structures. (EV)

  8. Development of the Parental Self-Efficacy Scale for Child Autonomy toward Minor Surgery (PSESCAMS): based on results of questionnaire surveys of parents raising children between 3 and 6 years old.

    PubMed

    Ono, Satomi; Manabe, Yukiko

    2014-07-01

    The aim of this study is to prepare the Parental Self-Efficacy Scale for Child Autonomy toward Minor Surgery (PSESCAMS) and verify its reliability and validity. The PSESCAMS was developed based on the findings of previous qualitative studies on preschool children aged 3-6 years who were undergoing day surgery and their parents. The Generalized Self-Efficacy Scale, Maternal Self-Accomplishment Scale (MSAS), and Japanese-language version of the State-Trait Anxiety Inventory A-trait subscale (STAI: A-trait) were used to examine the criterion-related validity of the PSESCAMS. In addition, the test-retest method was utilized for the PSESCAMS. The number of valid responses was 586. A principle component analysis of the PSESCAMS was conducted of 18 items, extracting two factors. As a result of factor analysis that assumed two factors, the two factors were named "self-efficacy for support related to child's emotional control for minor surgery" and "self-efficacy for support related to child's understanding of minor surgery". A structural equation model having high goodness of fit for the PSESCAMS was shown by a covariance structure analysis. The correlations between GSES, MSAS, STAI: A-trait and the PSESCAMS were r = 0.323 (P < 0.001), r = 0.370 (P < 0.001), and r = -0.248 (P < 0.001), respectively. Cronbach's alpha of both the initial test and the test-retest for the PSESCAMS were 0.9 and the correlation between both was significant. The PSESCAMS consists of two categories and includes 18 items. The reliability and validity of the PSESCAMS were proved. © 2013 The Authors. Japan Journal of Nursing Science © 2013 Japan Academy of Nursing Science.

  9. [Perissodactyla: the primary structure of hemoglobins from the lowland tapir (Tapirus terrestris): glutamic acid in position 2 of the beta chains].

    PubMed

    Mazur, G; Braunitzer, G

    1984-09-01

    The hemoglobins from a lowland tapir (Tapirus terrestris) were analysed and the complete primary structure is described. The globin chains were separated on CM cellulose column in 8M urea and the amino-acid sequences were determined in the liquid phase sequenator. The results show that globin consists of two alpha chains (alpha I and alpha II) and beta major and beta minor components. The alpha chains differ only at one position: alpha I contains aspartic acid and alpha II glycine. The beta chains are heterogeneous: aspartic and glutamic acid were found at position beta 21 and beta 73 of the beta major components and asparagine and serine at position beta 139. In the beta minor components four positions were found with more than one amino acid, namely beta 2, beta 4, beta 6 and beta 56. The sequences are compared with those of man, horse and rhinoceros. Four residues of horse methemoglobin, which are involved in the alpha 1 beta 1 contacts are substituted in tapir hemoglobins. In the alpha chains: alpha 107(G14)Ser----Val, alpha 111-(G18) Val----Leu, alpha 115(GH3) Asn----Asp or Gly; in the beta chains: beta 116(G18) Arg----Gln. The amino acid at beta 2 of the major components is glutamic acid while glutamine and histidine are found in the minor components. Although glutamic acid, a binding site for ATP, does not interact with 2,3-bisphosphoglycerate, glutamine and histidine in the minor components are responsible for the slight effect of 2,3-bisphosphoglycerate on tapir hemoglobin.

  10. Environmental Assessment, Establishing a Drop Zone at the Energetic Materials Research and Testing Center in Socorro, New Mexico and Finding of No Significant Impact (FONSI)

    DTIC Science & Technology

    2007-11-07

    action is open space, and free of any residential or other structures . Biological Resources Minor impacts to vegetation and wildlife may occur from...mountains, rills, gullies, or other notable geologic features. There are no residences or other structures within the proposed drop zone. 3.2 Airspace...research, testing and training related to energetic materials. The land has also been used for livestock grazing. There are no structures on the

  11. Structural Basis of Cooperative Ligand Binding by the Glycine Riboswitch

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    E Butler; J Wang; Y Xiong

    2011-12-31

    The glycine riboswitch regulates gene expression through the cooperative recognition of its amino acid ligand by a tandem pair of aptamers. A 3.6 {angstrom} crystal structure of the tandem riboswitch from the glycine permease operon of Fusobacterium nucleatum reveals the glycine binding sites and an extensive network of interactions, largely mediated by asymmetric A-minor contacts, that serve to communicate ligand binding status between the aptamers. These interactions provide a structural basis for how the glycine riboswitch cooperatively regulates gene expression.

  12. Finding a Needle in the Haystack: Identification of Functionally Important Minority Phases in an Operating Battery

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Kai; Ren, Fang; Wang, Xuelong

    The in-depth understanding of the minority phases’ roles in functional materials, e.g., batteries, is critical for optimizing the system performance and the operational efficiency. Although the visualization of battery electrode under operating conditions has been demonstrated, the development of advanced data-mining approaches is still needed in order to identify minority phases and to understand their functionalities. The present study uses nanoscale X-ray spectromicroscopy to study a functional LiCoO 2/Li battery pouch cell. The data-mining approaches developed herein were used to search through over 10 million X-ray absorption spectra that cover more than 100 active cathode particles. Two particles with unanticipatedmore » chemical fingerprints were identified and further analyzed, providing direct evidence and valuable insight into the undesired side reactions involving the cation dissolution and precipitation as well as the local overlithiation-caused subparticle domain deactivation. As a result, the data-mining approach described in this work is widely applicable to many other structurally complex and chemically heterogeneous systems, in which the secondary/minority phases could critically affect the overall performance of the system, well beyond battery research.« less

  13. Comparison of computational methods to model DNA minor groove binders.

    PubMed

    Srivastava, Hemant Kumar; Chourasia, Mukesh; Kumar, Devesh; Sastry, G Narahari

    2011-03-28

    There has been a profound interest in designing small molecules that interact in sequence-selective fashion with DNA minor grooves. However, most in silico approaches have not been parametrized for DNA ligand interaction. In this regard, a systematic computational analysis of 57 available PDB structures of noncovalent DNA minor groove binders has been undertaken. The study starts with a rigorous benchmarking of GOLD, GLIDE, CDOCKER, and AUTODOCK docking protocols followed by developing QSSR models and finally molecular dynamics simulations. In GOLD and GLIDE, the orientation of the best score pose is closer to the lowest rmsd pose, and the deviation in the conformation of various poses is also smaller compared to other docking protocols. Efficient QSSR models were developed with constitutional, topological, and quantum chemical descriptors on the basis of B3LYP/6-31G* optimized geometries, and with this ΔT(m) values of 46 ligands were predicted. Molecular dynamics simulations of the 14 DNA-ligand complexes with Amber 8.0 show that the complexes are stable in aqueous conditions and do not undergo noticeable fluctuations during the 5 ns production run, with respect to their initial placement in the minor groove region.

  14. The Role of Distal Minority Stress and Internalized Transnegativity in Suicidal Ideation and Nonsuicidal Self-Injury Among Transgender Adults.

    PubMed

    Staples, Jennifer M; Neilson, Elizabeth C; Bryan, Amanda E B; George, William H

    Transgender people are at elevated risk for nonsuicidal self-injury (NSSI) and suicidal ideation compared to the general population. Transgender (trans) refers to a diverse group of people who experience incongruence between their gender identity and sex assigned at birth. The present study is guided by the minority stress model and the psychological mediation framework, which postulate that sexual minority groups experience elevated stress as a result of anti-minority prejudice, contributing to negative mental health outcomes. This study utilized these theories to investigate the role of internalized transnegativity-internalization of negative societal attitudes about one's trans identity-in the relationships of distal trans stress to suicidal ideation and NSSI. A U.S. national sample of trans adults (N = 237) completed a battery of online measures. Structural equation modeling (SEM) was used to compare models with mediation and moderation effects. Results suggested that internalized transnegativity acts as both a mediator and a moderator in the relationship between distal trans stress and suicidal ideation. Log likelihood comparisons suggested moderation models had the superior fit for these data. Results suggest that clinical interventions should directly target individuals' internalized transnegativity as well as societal-level transnegativity.

  15. Iowa State University's undergraduate minor, online graduate certificate and resource center in NDE

    NASA Astrophysics Data System (ADS)

    Bowler, Nicola; Larson, Brian F.; Gray, Joseph N.

    2014-02-01

    Nondestructive evaluation is a `niche' subject that is not yet offered as an undergraduate or graduate major in the United States. The undergraduate minor in NDE offered within the College of Engineering at Iowa State University (ISU) provides a unique opportunity for undergraduate aspiring engineers to obtain a qualification in the multi-disciplinary subject of NDE. The minor requires 16 credits of course work within which a core course and laboratory in NDE are compulsory. The industrial sponsors of Iowa State's Center for Nondestructive Evaluation, and others, strongly support the NDE minor and actively recruit students from this pool. Since 2007 the program has graduated 10 students per year and enrollment is rising. In 2011, ISU's College of Engineering established an online graduate certificate in NDE, accessible not only to campus-based students but also to practicing engineers via the web. The certificate teaches the fundamentals of three major NDE techniques; eddy-current, ultrasonic and X-ray methods. This paper describes the structure of these programs and plans for development of an online, coursework-only, Master of Engineering in NDE and thesis-based Master of Science degrees in NDE.

  16. A qualitative study of perceived social barriers to care for eating disorders: Perspectives from ethnically diverse health care consumers

    PubMed Central

    Becker, Anne E; Hadley Arrindell, Adrienne; Perloe, Alexandra; Fay, Kristen; Striegel-Moore, Ruth H

    2010-01-01

    Objective: The study aim was to identify and describe health consumer perspectives on social barriers to care for eating disorders in an ethnically diverse sample. Method: We conducted an exploratory secondary analysis of qualitative data comprising transcripts from semi-structured interviews with past and prospective consumers of eating disorder treatment (n = 32). Transcripts were inputted into NVivo 8 for coding, sorting, and quantifying thematic content of interest within strata defined by ethnic minority and non-minority participants. We then examined the influence of key social barriers—including stigma and social stereotypes—on perceived impact on care. Results: The majority of respondents (78%) endorsed at least one social barrier to care for an eating or weight concern. Perceived stigma (or shame) and social stereotyping—identified both within social networks and among clinicians—had adversely impacted care for 59% and 19% of respondents, respectively. Discussion: Social barriers to care for eating and weight related concerns may be prevalent in the U.S. and impact both ethnic minority and non-minority health care consumers. © 2009 by Wiley Periodicals, Inc. (Int J Eat Disord 2010;) PMID:19806607

  17. The impact of culturally responsive self-management interventions on health outcomes for minority populations: A systematic review.

    PubMed

    Ehrlich, Carolyn; Kendall, Elizabeth; Parekh, Sanjoti; Walters, Caroline

    2016-03-01

    The health of people from Indigenous and ethnic minorities is poorer than the remainder of the population. Frequently, Westernized health systems respond by introducing self-management interventions to improve chronic illness health outcomes. The aim of this study was to answer the research question: "Can self-management programs that have been adapted or modified still be effective for ethnic minority and Indigenous populations?" A systematic review across four databases was conducted. Twenty-three publications met the inclusion criteria. As the studies were heterogeneous, meta-analysis was not possible. Overall, interventions resulted in more positive health outcomes than usual care, but findings were inconsistent. We argue that rather than focusing on individual skills, knowledge, self-efficacy, and attitudes toward self-management, it may be more important to explore the structures and processes that underpin the sharing of information and skills within clinical or education encounters. Given that self-management is a Western cultural construct, creating empathic and responsive systems might be more effective for improving health of Indigenous and ethnic minority groups rather than relying predominantly on individual skill development. © The Author(s) 2015.

  18. Finding a Needle in the Haystack: Identification of Functionally Important Minority Phases in an Operating Battery

    DOE PAGES

    Zhang, Kai; Ren, Fang; Wang, Xuelong; ...

    2017-11-08

    The in-depth understanding of the minority phases’ roles in functional materials, e.g., batteries, is critical for optimizing the system performance and the operational efficiency. Although the visualization of battery electrode under operating conditions has been demonstrated, the development of advanced data-mining approaches is still needed in order to identify minority phases and to understand their functionalities. The present study uses nanoscale X-ray spectromicroscopy to study a functional LiCoO 2/Li battery pouch cell. The data-mining approaches developed herein were used to search through over 10 million X-ray absorption spectra that cover more than 100 active cathode particles. Two particles with unanticipatedmore » chemical fingerprints were identified and further analyzed, providing direct evidence and valuable insight into the undesired side reactions involving the cation dissolution and precipitation as well as the local overlithiation-caused subparticle domain deactivation. As a result, the data-mining approach described in this work is widely applicable to many other structurally complex and chemically heterogeneous systems, in which the secondary/minority phases could critically affect the overall performance of the system, well beyond battery research.« less

  19. DNA nanostructures: Through, rather than across

    NASA Astrophysics Data System (ADS)

    Bruchez, Marcel P.

    2018-02-01

    Dye molecules are shown to assemble into J-aggregate arrays by sequence-specific organization in the minor groove of DNA duplex sequences. Energy transfer through these structures displays the hallmarks of coherent coupling over distances that exceed those of conventional dipole-coupling processes.

  20. Privacy, Schooling, and Minors.

    ERIC Educational Resources Information Center

    Vandergrift, Kay E.

    1991-01-01

    Arguing that public education is not structured to encourage or respect students' privacy, this article questions several pedagogical approaches; types of assignments (e.g., autobiographical writing); types of computer-assisted instruction and other applications of technology; reference interviewing techniques; and other practices of librarians…

  1. 75 FR 37371 - Fisheries of the Exclusive Economic Zone Off Alaska; Fisheries of the Bering Sea Subarea

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-29

    ... current northern boundary of the NBSRA leaves an area open to nonpelagic trawling near the Bering Strait....062 The fourth minor technical amendment would replace outdated language describing the structure of...

  2. Equilibrium structures and flows of polar and nonpolar liquids in different carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Abramyan, Andrey K.; Bessonov, Nick M.; Mirantsev, Leonid V.; Chevrychkina, Anastasiia A.

    2018-03-01

    Molecular dynamics (MD) simulations of equilibrium structures and flows of polar water and nonpolar methane confined by single-walled carbon nanotubes (SWCNTs) with circular and square cross sections and bounding walls with regular graphene structure and random (amorphous) distribution of carbon atoms have been performed. The results of these simulations show that equilibrium structures of both confined liquids depend strongly on the shape of the cross section of SWCNTs, whereas the structure of their bounding walls has a minor influence on these structures. On contrary, the external pressure driven water and methane flows through above mentioned SWCNTs depend significantly on both the shape of their cross sections and the structure of their bounding walls.

  3. Complexes of mismatched and complementary DNA with minor groove binders. Structures at nucleotide resolution via an improved hydroxyl radical cleavage methodology.

    PubMed

    Bialonska, Dobroslawa; Song, Kenneth; Bolton, Philip H

    2011-11-27

    Tumor cell lines can replicate faster than normal cells and many also have defective DNA repair pathways. This has lead to the investigation of the inhibition of DNA repair proteins as a means of therapeutic intervention. An alternative approach is to hide or mask damaged DNA from the repair systems. We have developed a protocol to investigate the structures of the complexes of damaged DNA with drug like molecules. Nucleotide resolution structural information can be obtained using an improved hydroxyl radical cleavage protocol. The use of a dT(n) tail increases the length of the smallest fragments of interest and allows efficient co-precipitation of the fragments with poly(A). The use of a fluorescent label, on the 5' end of the dT(n) tail, in conjunction with modified cleavage reaction conditions, avoids the lifetime and other problems with (32)P labeling. The structures of duplex DNAs containing AC and CC mismatches in the presence and absence of minor groove binders have been investigated as have those of the fully complementary DNA. The results indicate that the structural perturbations of the mismatches are localized, are sequence dependent and that the presence of a mismatch can alter the binding of drug like molecules. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. NMR solution structure of an N2-guanine DNA adduct derived from the potent tumorigen dibenzo[a,l]pyrene: Intercalation from the minor groove with ruptured Watson-Crick base pairing

    PubMed Central

    Tang, Yijin; Liu, Zhi; Ding, Shuang; Lin, Chin H.; Cai, Yuqin; Rodriguez, Fabian A.; Sayer, Jane M.; Jerina, Donald M.; Amin, Shantu; Broyde, Suse; Geacintov, Nicholas E.

    2012-01-01

    The most potent tumorigen identified among the polycyclic aromatic hydrocarbons (PAH) is the non-planar fjord region dibenzo[a,l]pyrene (DB[a,l]P). It is metabolically activated in vivo through the widely-studied diol epoxide (DE) pathway to form covalent adducts with DNA bases, predominantly guanine and adenine. The (+)-11S,12R,13R,14S DE enantiomer forms adducts via its C14-position with the exocyclic amino group of guanine. Here, we present the first NMR solution structure of a DB[a,l]P-derived adduct, the 14R (+)-trans-anti-DB[a,l]P–N2-dG (DB[a,l]P-dG) lesion in double-stranded DNA. In contrast to the stereochemically identical benzo[a]pyrene-derived N2-dG adduct (B[a]P-dG) in which the B[a]P rings reside in the B-DNA minor groove on the 3’-side of the modifed deoxyguanosine, in the DB[a,l]P-derived adduct the DB[a,l]P rings intercalate into the duplex on the 3’-side of the modified base from the sterically crowded minor groove. Watson-Crick base pairing of the modified guanine with the partner cytosine is broken, but these bases retain some stacking with the bulky DB[a,l]P ring system. This new theme in PAH DE - DNA adduct conformation differs from: (1) the classical intercalation motif where Watson-Crick base-pairing is intact at the lesion site, and (2) the base-displaced intercalation motif in which the damaged base and its partner are extruded from the helix . The structural considerations that lead to the intercalated conformation of the DB[a,l]P-dG lesion in contrast to the minor groove alignment of the B[a]P-dG adduct, and the implications of the DB[a,l]P-dG conformational motif for the recognition of such DNA lesions by the human nucleotide excision repair apparatus, are discussed. PMID:23121427

  5. Nuclear magnetic resonance solution structure of an N(2)-guanine DNA adduct derived from the potent tumorigen dibenzo[a,l]pyrene: intercalation from the minor groove with ruptured Watson-Crick base pairing.

    PubMed

    Tang, Yijin; Liu, Zhi; Ding, Shuang; Lin, Chin H; Cai, Yuqin; Rodriguez, Fabian A; Sayer, Jane M; Jerina, Donald M; Amin, Shantu; Broyde, Suse; Geacintov, Nicholas E

    2012-12-04

    The most potent tumorigen identified among the polycyclic aromatic hydrocarbons (PAH) is the nonplanar fjord region dibenzo[a,l]pyrene (DB[a,l]P). It is metabolically activated in vivo through the widely studied diol epoxide (DE) pathway to form covalent adducts with DNA bases, predominantly guanine and adenine. The (+)-11S,12R,13R,14S DE enantiomer forms adducts via its C14 position with the exocyclic amino group of guanine. Here, we present the first nuclear magnetic resonance solution structure of a DB[a,l]P-derived adduct, the 14R-(+)-trans-anti-DB[a,l]P-N(2)-dG (DB[a,l]P-dG) lesion in double-stranded DNA. In contrast to the stereochemically identical benzo[a]pyrene-derived N(2)-dG adduct (B[a]P-dG) in which the B[a]P rings reside in the B-DNA minor groove on the 3'-side of the modifed deoxyguanosine, in the DB[a,l]P-derived adduct the DB[a,l]P rings intercalate into the duplex on the 3'-side of the modified base from the sterically crowded minor groove. Watson-Crick base pairing of the modified guanine with the partner cytosine is broken, but these bases retain some stacking with the bulky DB[a,l]P ring system. This new theme in PAH DE-DNA adduct conformation differs from (1) the classical intercalation motif in which Watson-Crick base pairing is intact at the lesion site and (2) the base-displaced intercalation motif in which the damaged base and its partner are extruded from the helix. The structural considerations that lead to the intercalated conformation of the DB[a,l]P-dG lesion in contrast to the minor groove alignment of the B[a]P-dG adduct, and the implications of the DB[a,l]P-dG conformational motif for the recognition of such DNA lesions by the human nucleotide excision repair apparatus, are discussed.

  6. Tigloylshikonin, a new minor Shikonin derivative, from the roots and the commercial root extract of lithospermum erythrorhizon.

    PubMed

    Ito, Yusai; Onobori, Kenichi; Yamazaki, Takeshi; Kawamura, Yoko

    2011-01-01

    Tigloylshikonin, a new shikonin derivative esterified with tiglic acid ((E)-2-methylbut-2-enoic acid), was isolated as a minor pigment from a food colorant "Shikon color," a commercial root extract from Lithospermum erythrorhizon SIEBOLD et ZUCCARINI. The structure of tigloylshikonin was elucidated using (1)H, (13)C, the difference nuclear Overhauser effect (NOE), and 2D NMR techniques. Its stereochemistry was determined by chiral-phase HPLC analysis. Tigloylshikonin was also found in the roots of L. erythrorhizon, which indicated that this new shikonin derivative is a typical component of naphthoquinone pigments in the roots of L. erythrorhizon.

  7. Beliefs about causes, symptoms, and stigma associated with severe mental illness among 'highly acculturated' Chinese-American patients.

    PubMed

    Lin, Susan Y

    2013-12-01

    Literature about experiences of mental illness among ethnic minority has tended to focus on first-generation migrants. This study fills that gap by exploring experiences among highly acculturated Chinese-American patients with mental illness. Twenty-nine participants completed semi-structured interviews based on Kleinman's explanatory model, which were audio-taped, transcribed and coded for qualitative analysis. Beliefs about the causes of mental illness included biological factors, head trauma and personal losses. Issues relating to stigma and shame were also discussed. Highly acculturated ethnic minority patients may ascribe to a biomedical model at the same time as ascribing to culture-specific beliefs.

  8. Triterpenoid Saponins from Anemone rivularis var. Flore-Minore and Their Anti-Proliferative Activity on HSC-T6 Cells.

    PubMed

    Wang, Xiao-Yang; Gao, Hui; Xie, Xiao-Jie; Jurhiin, Jirimubatu; Zhang, Mu-Zi-He; Zhou, Yan-Ping; Liu, Rui; Ning, Meng; Han, Jin; Tang, Hai-Feng

    2018-02-23

    Five previously undescribed triterpenoid saponins ( 1 - 5 ), along with eight known ones ( 6 - 13 ), were isolated from the whole plants of Anemone rivularis var. flore-minore . Their structures were clarified by extensive spectroscopic data and chemical evidence. For the first time, the lupane-type saponins ( 3 and 12 ) were reported from the Anemone genus. The anti-proliferative activity of all isolated saponins was evaluated on hepatic stellate cells (HSC-T6). Saponins 12 and 13 , which possess more monosaccharides than the others, displayed potent anti-proliferative activity, with IC 50 values of 18.21 and 15.56 μM, respectively.

  9. Structure of new carotenoids with the 6-oxo-kappa end group from the fruits of paprika, Capsicum annuum.

    PubMed

    Maoka, Takashi; Akimoto, Naoshige; Fujiwara, Yasuhiro; Hashimoto, Keiji

    2004-01-01

    New carotenoids 1 and 2 were isolated as minor components from the ripe fruits of paprika (Capsicum annuum). The structures of 1 and 2 were determined to be (3R,5'R)-3-hydroxy-beta,kappa-caroten-6'-one and (5'R)-3,4-didehydro-beta,kappa-caroten-6'-one, respectively, from UV-vis, NMR, CD, HRFABMS, and FABMS/MS spectra.

  10. Long-term effects of marijuana use on the brain

    PubMed Central

    Filbey, Francesca M.; Aslan, Sina; Calhoun, Vince D.; Spence, Jeffrey S.; Damaraju, Eswar; Caprihan, Arvind; Segall, Judith

    2014-01-01

    Questions surrounding the effects of chronic marijuana use on brain structure continue to increase. To date, however, findings remain inconclusive. In this comprehensive study that aimed to characterize brain alterations associated with chronic marijuana use, we measured gray matter (GM) volume via structural MRI across the whole brain by using voxel-based morphology, synchrony among abnormal GM regions during resting state via functional connectivity MRI, and white matter integrity (i.e., structural connectivity) between the abnormal GM regions via diffusion tensor imaging in 48 marijuana users and 62 age- and sex-matched nonusing controls. The results showed that compared with controls, marijuana users had significantly less bilateral orbitofrontal gyri volume, higher functional connectivity in the orbitofrontal cortex (OFC) network, and higher structural connectivity in tracts that innervate the OFC (forceps minor) as measured by fractional anisotropy (FA). Increased OFC functional connectivity in marijuana users was associated with earlier age of onset. Lastly, a quadratic trend was observed suggesting that the FA of the forceps minor tract initially increased following regular marijuana use but decreased with protracted regular use. This pattern may indicate differential effects of initial and chronic marijuana use that may reflect complex neuroadaptive processes in response to marijuana use. Despite the observed age of onset effects, longitudinal studies are needed to determine causality of these effects. PMID:25385625

  11. Isopeptide bonds of the major pilin protein BcpA influence pilus structure and bundle formation on the surface of Bacillus cereus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hendrickx, Antoni P.A.; Poor, Catherine B.; Jureller, Justin E.

    Bacillus cereus strains elaborate pili on their surface using a mechanism of sortase-mediated cross-linking of major and minor pilus components. Here we used a combination of electron microscopy and atomic force microscopy to visualize these structures. Pili occur as single, double or higher order assemblies of filaments formed from monomers of the major pilin, BcpA, capped by the minor pilin, BcpB. Previous studies demonstrated that within assembled pili, four domains of BcpA -- CNA{sub 1}, CNA{sub 2}, XNA and CNA{sub 3} -- each acquire intramolecular lysine-asparagine isopeptide bonds formed via catalytic glutamic acid or aspartic acid residues. Here we showedmore » that mutants unable to form the intramolecular isopeptide bonds in the CNA2 or CNA3 domains retain the ability to form pilus bundles. A mutant lacking the CNA{sub 1} isopeptide bond assembled deformed pilin subunits that failed to associate as bundles. X-ray crystallography revealed that the BcpA variant Asp{sup 312}Ala, lacking an aspartyl catalyst, did not generate the isopeptide bond within the jelly-roll structure of XNA. The Asp{sup 312}Ala mutant was also unable to form bundles and promoted the assembly of deformed pili. Thus, structural integrity of the CNA{sub 1} and XNA domains are determinants for the association of pili into higher order bundle structures and determine native pilus structure.« less

  12. Structural studies of p53 inactivation by DNA-contact mutations and its rescue by suppressor mutations via alternative protein–DNA interactions

    PubMed Central

    Eldar, Amir; Rozenberg, Haim; Diskin-Posner, Yael; Rohs, Remo; Shakked, Zippora

    2013-01-01

    A p53 hot-spot mutation found frequently in human cancer is the replacement of R273 by histidine or cysteine residues resulting in p53 loss of function as a tumor suppressor. These mutants can be reactivated by the incorporation of second-site suppressor mutations. Here, we present high-resolution crystal structures of the p53 core domains of the cancer-related proteins, the rescued proteins and their complexes with DNA. The structures show that inactivation of p53 results from the incapacity of the mutated residues to form stabilizing interactions with the DNA backbone, and that reactivation is achieved through alternative interactions formed by the suppressor mutations. Detailed structural and computational analysis demonstrates that the rescued p53 complexes are not fully restored in terms of DNA structure and its interface with p53. Contrary to our previously studied wild-type (wt) p53-DNA complexes showing non-canonical Hoogsteen A/T base pairs of the DNA helix that lead to local minor-groove narrowing and enhanced electrostatic interactions with p53, the current structures display Watson–Crick base pairs associated with direct or water-mediated hydrogen bonds with p53 at the minor groove. These findings highlight the pivotal role played by R273 residues in supporting the unique geometry of the DNA target and its sequence-specific complex with p53. PMID:23863845

  13. Thrust Belt Architecture of the Central and Southern Western Foothills of Taiwan

    NASA Astrophysics Data System (ADS)

    Rodriguez, F.; Wiltschko, D.

    2006-12-01

    A structural model of the central and southern Western Foothills Fold and Thrust Belt (WFFTB) was constructed from serial balanced cross sections using available surface, drill, seismic and thermochronologic data. The WFFTB is composed of four main thrust sheets with minor splays. On the east, the Tulungwan fault, which separates the sedimentary rocks of the WFFTB from the low grade meta-sediments of the Slate Belt, evolves from a basement cored fold in the north (around 24°10' N) where the conformable contact between foothills sediments and meta-sediments from the Slate Belt on its western flank is present. At this point the tip of the fault is below the unconformity and the displacement amount is small. To the south this fault breaks the back limb of the fold and gains displacement, and continues gaining displacement to the south. The next thrust sheet to the west includes the Schuantung, Fenghuangchan, Luku, Tatou, Hopiya, and Pingchi faults. This fault system is interpreted as characterized by a long flat with small ramps along a Miocene detachment, not a series of imbricates, as it has been interpreted before. The next thrust sheet to the west is the Chulungupu-Chukou-Lunhou, this system appears to gain displacement to the south as the Schuantung fault system decreases in amount of displacement. The Chulungpu-Chukou-Lunhou fault system contains a wide monocline in the central foothills related with the Chulungpu fault and two wide synclines in the southern part, the Yuching and Tinpligling synclines. Modeling of these two last structures shows that both are uplifted with respect to the regional level above a wide and flat feature; the footwall of the Lunhou fault is a monocline. A geometric solution to lift the Lunhou system involves a major fault-bend-fold anticline with a long ramp and a detachment at ~13 km of depth. It explains, 1) the frontal monocline, which is the from limb of this fault-bend- fold, 2) the minor structures associated with minor back-thrusts and wedging, and 3) the uplift of the structures above the regional level over a wide anticlinal crest. The last thrust system toward the west shows a series of structures which closely associated with the Peikang high implying that the structures are either inversion structures or new thrust faults whose ramps are located in pre-existing normal faults.

  14. Do Low Income Youth of Color See “The Bigger Picture” When Discussing Type 2 Diabetes: A Qualitative Evaluation of a Public Health Literacy Campaign

    PubMed Central

    Schillinger, Dean; Tran, Jessica; Fine, Sarah

    2018-01-01

    As Type 2 diabetes spikes among minority and low-income youth, there is an urgent need to tackle the drivers of this preventable disease. The Bigger Picture (TBP) is a counter-marketing campaign using youth-created, spoken-word public service announcements (PSAs) to reframe the epidemic as a socio-environmental phenomenon requiring communal action, civic engagement and norm change. Methods: We examined whether and how TBP PSAs advance health literacy among low-income, minority youth. We showed nine PSAs, asking individuals open-ended questions via questionnaire, then facilitating a focus group to reflect upon the PSAs. Results: Questionnaire responses revealed a balance between individual vs. public health literacy. Some focused on individual responsibility and behaviors, while others described socio-environmental forces underlying risk. The focus group generated a preponderance of public health literacy responses, emphasizing future action. Striking sociopolitical themes emerged, reflecting tensions minority and low-income youth experience, such as entrapment vs. liberation. Conclusion: Our findings speak to the structural barriers and complexities underlying diabetes risk, and the ability of spoken word medium to make these challenges visible and motivate action. Practice Implications: Delivering TBP content to promote interactive reflection has potential to change behavioral norms and build capacity to confront the social, economic and structural factors that influence behaviors. PMID:29695114

  15. Origin, growth, and rupture of saccular aneurysms: a review.

    PubMed

    Sekhar, L N; Heros, R C

    1981-02-01

    Pathological and hemodynamic concepts regarding the origin, growth, and rupture of intracranial saccular aneurysms are reviewed. Aneurysms form as a result of an interplay between hemodynamic factors, such as axial stream impingement and the water hammer effect, and structural weaknesses at apices of arterial bifurcations, such as congenital and acquired medial defects, funnel-shaped dilatations, and areas of thinning. Hypertension and time aid the formation of aneurysms. Unknown factors in women and in some families also play a role. Enlargement of aneurysms results from an interplay between mechanical factors, such as self-excitation and resonance, that produce structural fatigue and pathological processes of repair of the aneurysmal wall. Rupture of aneurysms is caused by the same hemodynamic factors that effect growth and is also influenced by extramural pressure. Pathologically, a major rupture may be preceded by fibrinous and leukocytic infiltration of the wall, bleb formation, and a minor hemorrhage. Such minor leaks can be followed by healing and growth. Aneurysms that escape major hemorrhage or heal successfully after a hemorrhage can grow to giant proportions, but remain susceptible to rupture despite their size, unless they become completely thrombosed. Intramural thrombosis may be stimulated by minor leaks and is dependent upon the physical characteristics of aneurysms. Experimental, angiographic, and clinical studies that pertain to the origin, growth, and rupture of aneurysms are also reviewed.

  16. Community pharmacy minor ailment services in England: Pharmacy stakeholder perspectives on the factors affecting sustainability.

    PubMed

    Nazar, Hamde; Nazar, Zachariah

    2018-05-14

    Self-care advice and management of minor ailments have long been provided in community pharmacies across England. However, formal pharmacy minor ailment service provision is geographically variable and has yet to gain recognition and political support as a valued sustainable service for nationwide adoption and commissioning. To investigate the sustainability potential of pharmacy minor ailment services from the perspective of community pharmacy stakeholders within the North East of England. A mixed methods approach was adopted to survey and interview stakeholders from the North East of England who commission; provide; and/or represent groups influencing the design, delivery and investment in community pharmacy clinical and public health services. The 40-item Programme Sustainability Assessment Tool, a validated instrument to assess a public health programme's capacity for sustainability across eight domains, was administered to fifty-three stakeholders, identified from a pharmacy minor ailments showcase event. The same stakeholders were invited for a semi-structured interview to explore issues further. Interviews were audio-recorded, transcribed verbatim, and underwent framework analysis. Forty-two (79.2% response rate) stakeholders representing commissioning, provider and influencing (e.g. Local Professional Network) organisations completed the assessment tool. Pharmacy minor ailment services were rated as unsustainable across the majority of the domains. Elements within the domain 'Partnerships' demonstrated potential for sustainability. Stakeholder interviews provided detailed explanation for the low scoring sustainability domains, highlighting the multifaceted challenges threatening these services. The Programme Sustainability Assessment Tool allowed stakeholders to evaluate the potential of pharmacy minor ailment services in England. Follow-up interviews highlighted that initial design and implementation of services was poorly conceived and lacked evidence, thereby impeding the services' sustainability. There are many challenges facing a widespread provision of pharmacy ailment services, but it is clear the profession needs to be clear on the service objectives to secure future interest and investment. Copyright © 2018. Published by Elsevier Inc.

  17. Current intimate relationship status, depression, and alcohol use among bisexual women: The mediating roles of bisexual-specific minority stressors

    PubMed Central

    Molina, Yamile; Marquez, Jacob H.; Logan, Diane E.; Leeson, Carissa J.; Balsam, Kimberly F.; Kaysen, Debra L.

    2015-01-01

    Current intimate relationship characteristics, including gender and number of partner(s), may affect one's visibility as a bisexual individual and the minority stressors they experience, which may in turn influence their health. The current study tested four hypotheses: 1) minority stressors vary by current intimate relationship status; 2) higher minority stressors are associated with higher depressive symptoms and alcohol-related outcomes; 3) depressive symptoms and alcohol-related outcomes vary by current intimate relationship status; and 4) minority stressors will mediate differences in these outcomes. Participants included 470 self-identified bisexual women (65% Caucasian, mean age: 21) from a sample of sexual minority women recruited from different geographic regions in the United States through advertisements on social networking sites and Craigslist. Participants completed a 45 minute survey. Respondents with single partners were first grouped by partner gender (male partner: n=282; female partner: n=56). Second, women were grouped by partner gender/number (single female/male partner: n = 338; women with multiple female and male partners: n=132). Women with single male partners and women with multiple male and female partners exhibited elevated experienced bi-negativity and differences in outness (H1). Experienced and internalized bi-negativity were associated with health outcomes, but not outness (H2). Differences in outcomes emerged by partner number and partner number/gender (H3); these differences were mediated by experienced bi-negativity (H4). These results suggest that experiences of discrimination may underlie differences in health related to bisexual women's relationship structure and highlight the importance of evaluating women's relational context as well as sexual identification in understanding health risk behaviors. PMID:26456995

  18. Current intimate relationship status, depression, and alcohol use among bisexual women: The mediating roles of bisexual-specific minority stressors.

    PubMed

    Molina, Yamile; Marquez, Jacob H; Logan, Diane E; Leeson, Carissa J; Balsam, Kimberly F; Kaysen, Debra L

    2015-07-01

    Current intimate relationship characteristics, including gender and number of partner(s), may affect one's visibility as a bisexual individual and the minority stressors they experience, which may in turn influence their health. The current study tested four hypotheses: 1) minority stressors vary by current intimate relationship status; 2) higher minority stressors are associated with higher depressive symptoms and alcohol-related outcomes; 3) depressive symptoms and alcohol-related outcomes vary by current intimate relationship status; and 4) minority stressors will mediate differences in these outcomes. Participants included 470 self-identified bisexual women (65% Caucasian, mean age: 21) from a sample of sexual minority women recruited from different geographic regions in the United States through advertisements on social networking sites and Craigslist. Participants completed a 45 minute survey. Respondents with single partners were first grouped by partner gender (male partner: n=282; female partner: n=56). Second, women were grouped by partner gender/number (single female/male partner: n = 338; women with multiple female and male partners: n=132). Women with single male partners and women with multiple male and female partners exhibited elevated experienced bi-negativity and differences in outness (H1). Experienced and internalized bi-negativity were associated with health outcomes, but not outness (H2). Differences in outcomes emerged by partner number and partner number/gender (H3); these differences were mediated by experienced bi-negativity (H4). These results suggest that experiences of discrimination may underlie differences in health related to bisexual women's relationship structure and highlight the importance of evaluating women's relational context as well as sexual identification in understanding health risk behaviors.

  19. Minor element distribution in iron disulfides in coal: a geochemical review

    USGS Publications Warehouse

    Kolker, Allan

    2012-01-01

    Electron beam microanalysis of coal samples in U.S. Geological Survey (USGS) labs confirms that As is the most abundant minor constituent in Fe disulfides in coal and that Se, Ni, and other minor constituents are present less commonly and at lower concentrations than those for As. In nearly all cases, Hg occurs in Fe disulfides in coal at concentrations below detection by electron beam instruments. Its presence is shown by laser ablation ICP-MS, by selective leaching studies of bulk coal, and by correlation with Fe disulfide proxies such as total Fe and pyritic sulfur. Multiple generations of Fe disulfides are present in coal. These commonly show grain-to-grain and within-grain minor- or trace element compositional variation that is a function of the early diagenetic, coalification, and post-coalification history of the coal. Framboidal pyrite is almost always the earliest Fe disulfide generation, as shown by overgrowths of later Fe disulfides which may include pyrite or marcasite. Cleat- (or vein) pyrite (or marcasite) is typically the latest Fe disulfide generation, as shown by cross-cutting relations. Cleat pyrite forms by fluid migration within a coal basin and consequently may be enriched in elements such as As by deposition from compaction-driven fluids, metal enriched basinal brines or hydrothermal fluids. In some cases, framboidal pyrite shows preferential Ni enrichment with respect to co-occurring pyrite forms. This is consistent with bacterial complexing of metals in anoxic sediments and derivation of framboidal pyrite from greigite (Fe3S4), an Fe monosulfide precursor to framboidal pyrite having the thio-spinel structure which accommodates transition metals. Elements such as As, Se, and Sb substitute for S in the pyrite structure whereas metals, including transition metals, Hg and Pb, are thought to substitute for Fe. Understanding the distribution of minor and trace elements in Fe disulfides in coal has important implications for their availability to the environment through coal mining and use, as well as for potential reduction by coal preparation, and for delineating diagenetic compositional changes throughout and after coal formation.

  20. Shiga toxins: A review of structure, mechanism, and detection

    USDA-ARS?s Scientific Manuscript database

    Although Shiga toxin (Stx)-producing Escherichia coli (STEC) are responsible for a minority of foodborne disease outbreaks in the United States, they account for a disproportionately large number of hospitalizations, serious sequelae, and deaths associated with foodborne illness. Diseases caused b...

  1. Developing a systems-based framework of the factors influencing dietary and physical activity behaviours in ethnic minority populations living in Europe - a DEDIPAC study.

    PubMed

    Holdsworth, Michelle; Nicolaou, Mary; Langøien, Lars Jørun; Osei-Kwasi, Hibbah Araba; Chastin, Sebastien F M; Stok, F Marijn; Capranica, Laura; Lien, Nanna; Terragni, Laura; Monsivais, Pablo; Mazzocchi, Mario; Maes, Lea; Roos, Gun; Mejean, Caroline; Powell, Katie; Stronks, Karien

    2017-11-07

    Some ethnic minority populations have a higher risk of non-communicable diseases than the majority European population. Diet and physical activity behaviours contribute to this risk, shaped by a system of inter-related factors. This study mapped a systems-based framework of the factors influencing dietary and physical activity behaviours in ethnic minority populations living in Europe, to inform research prioritisation and intervention development. A concept mapping approach guided by systems thinking was used: i. Preparation (protocol and terminology); ii. Generating a list of factors influencing dietary and physical activity behaviours in ethnic minority populations living in Europe from evidence (systematic mapping reviews) and 'eminence' (89 participants from 24 academic disciplines via brainstorming, an international symposium and expert review) and; iii. Seeking consensus on structuring, rating and clustering factors, based on how they relate to each other; and iv. Interpreting/utilising the framework for research and interventions. Similar steps were undertaken for frameworks developed for the majority European population. Seven distinct clusters emerged for dietary behaviour (containing 85 factors) and 8 for physical activity behaviours (containing 183 factors). Four clusters were similar across behaviours: Social and cultural environment; Social and material resources; Psychosocial; and Migration context. Similar clusters of factors emerged in the frameworks for diet and physical activity behaviours of the majority European population, except for 'migration context'. The importance of factors across all clusters was acknowledged, but their relative importance differed for ethnic minority populations compared with the majority population. This systems-based framework integrates evidence from both expert opinion and published literature, to map the factors influencing dietary and physical activity behaviours in ethnic minority groups. Our findings illustrate that innovative research and complex interventions need to be developed that are sensitive to the needs of ethnic minority populations. A systems approach that encompasses the complexity of the inter-related factors that drive behaviours may inform a more holistic public health paradigm to more effectively reach ethnic minorities living in Europe, as well as the majority host population.

  2. Some Minorants and Majorants of Random Walks and Levy Processes

    NASA Astrophysics Data System (ADS)

    Abramson, Joshua Simon

    This thesis consists of four chapters, all relating to some sort of minorant or majorant of random walks or Levy processes. In Chapter 1 we provide an overview of recent work on descriptions and properties of the convex minorant of random walks and Levy processes as detailed in Chapter 2, [72] and [73]. This work rejuvenated the field of minorants, and led to the work in all the subsequent chapters. The results surveyed include point process descriptions of the convex minorant of random walks and Levy processes on a fixed finite interval, up to an independent exponential time, and in the infinite horizon case. These descriptions follow from the invariance of these processes under an adequate path transformation. In the case of Brownian motion, we note how further special properties of this process, including time-inversion, imply a sequential description for the convex minorant of the Brownian meander. This chapter is based on [3], which was co-written with Jim Pitman, Nathan Ross and Geronimo Uribe Bravo. Chapter 1 serves as a long introduction to Chapter 2, in which we offer a unified approach to the theory of concave majorants of random walks. The reasons for the switch from convex minorants to concave majorants are discussed in Section 1.1, but the results are all equivalent. This unified theory is arrived at by providing a path transformation for a walk of finite length that leaves the law of the walk unchanged whilst providing complete information about the concave majorant - the path transformation is different from the one discussed in Chapter 1, but this is necessary to deal with a more general case than the standard one as done in Section 2.6. The path transformation of Chapter 1, which is discussed in detail in Section 2.8, is more relevant to the limiting results for Levy processes that are of interest in Chapter 1. Our results lead to a description of a walk of random geometric length as a Poisson point process of excursions away from its concave majorant, which is then used to find a complete description of the concave majorant of a walk of infinite length. In the case where subsets of increments may have the same arithmetic mean (the more general case mentioned above), we investigate three nested compositions that naturally arise from our construction of the concave majorant. This chapter is based on [4], which was co-written with Jim Pitman. In Chapter 3, we study the Lipschitz minorant of a Levy process. For alpha > 0, the alpha-Lipschitz minorant of a function f : R→R is the greatest function m : R→R such that m ≤ f and | m(s) - m(t)| ≤ alpha |s - t| for all s, t ∈ R should such a function exist. If X = Xtt∈ R is a real-valued Levy process that is not pure linear drift with slope +/-alpha, then the sample paths of X have an alpha-Lipschitz minorant almost surely if and only if | E [X1]| < alpha. Denoting the minorant by M, we investigate properties of the random closed set Z := {t ∈ R : Mt = {Xt ∧ Xt-}, which, since it is regenerative and stationary, has the distribution of the closed range of some subordinator "made stationary" in a suitable sense. We give conditions for the contact set Z to be countable or to have zero Lebesgue measure, and we obtain formulas that characterize the Levy measure of the associated subordinator. We study the limit of Z as alpha → infinity and find for the so-called abrupt Levy processes introduced by Vigon that this limit is the set of local infima of X. When X is a Brownian motion with drift beta such that |beta| < alpha, we calculate explicitly the densities of various random variables related to the minorant. This chapter is based on [2], which was co-written with Steven N. Evans. Finally, in Chapter 4 we study the structure of the shocks for the inviscid Burgers equation in dimension 1 when the initial velocity is given by Levy noise, or equivalently when the initial potential is a two-sided Levy process This shock structure turns out to give rise to a parabolic minorant of the Levy process--see Section 4.2 for details. The main results are that when psi0 is abrupt in the sense of Vigon or has bounded variation with limsuph-2 h↓0y0 h=infinity , the set of points with zero velocity is regenerative, and that in the latter case this set is equal to the set of Lagrangian regular points, which is non-empty. When psi0 is abrupt the shock structure is discrete and when psi0 is eroded there are no rarefaction intervals. This chapter is based on [1].

  3. Structural stigma and sexual orientation disparities in adolescent drug use.

    PubMed

    Hatzenbuehler, Mark L; Jun, Hee-Jin; Corliss, Heather L; Bryn Austin, S

    2015-07-01

    Although epidemiologic studies have established the existence of large sexual orientation disparities in illicit drug use among adolescents and young adults, the determinants of these disparities remain understudied. This study sought to determine whether sexual orientation disparities in illicit drug use are potentiated in states that are characterized by high levels of stigma surrounding sexual minorities. State-level structural stigma was coded using a previously established measure based on a 4-item composite index: (1) density of same-sex couples; (2) proportion of Gay-Straight Alliances per public high school; (3) 5 policies related to sexual orientation discrimination (e.g., same-sex marriage, employment non-discrimination); and (4) public opinion toward homosexuality (aggregated responses from 41 national polls). The index was linked to individual-level data from the Growing Up Today Study, a prospective community-based study of adolescents (2001-2010). Sexual minorities report greater illicit drug use than their heterosexual peers. However, for both men and women, there were statistically significant interactions between sexual orientation status and structural stigma, such that sexual orientation disparities in marijuana and illicit drug use were more pronounced in high-structural stigma states than in low-structural stigma states, controlling for individual- and state-level confounders. For instance, among men, the risk ratio indicating the association between sexual orientation and marijuana use was 24% greater in high- versus low-structural stigma states, and for women it was 28% greater in high- versus low-structural stigma states. Stigma in the form of social policies and attitudes may contribute to sexual orientation disparities in illicit drug use. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Children in families with a severely mentally ill member. Prevalence and needs for support.

    PubMed

    Ostman, Margareta; Hansson, Lars

    2002-05-01

    The prevalence of minor children in families with a severely mentally ill member, these children's needs for support and the situation of the spouses were investigated as part of a multi-centre study of the quality of the mental health services in Sweden performed in 1986, 1991 and 1997. The sample was drawn from relatives of compulsorily and voluntarily admitted inpatients to acute psychiatric wards. The instrument used was a semi-structured questionnaire, interviewing relatives about the burden of relatives, their needs for support and participation in care and items concerning the situation of the under-aged children in these families. The results over the years investigated showed the same proportion of patients admitted to hospital who were also parents to minor children and a decreasing proportion of patients who had the custody of their children. Female patients were more often a parent and also more often had the custody of the children. The majority of the children had needs for support caused by their parent's illness and these needs were met in half of the cases. The healthy spouses in families with minor children more often had to give up their own occupation and to a higher extent experienced own needs for care and support from psychiatric services compared to spouses without minor children. The study supports that there is an urgent need for the psychiatric services to initiate parental issues in programmes for treatment and rehabilitation to ensure that the specific needs of minor children are met.

  5. Undergraduate optics program for the 21st Century

    NASA Astrophysics Data System (ADS)

    Palmer, James M.

    2002-05-01

    We have been offering a successful BS degree in optical engineering for the past ten years. We have produced more than 100 graduates, highly trained in basic optics and electronics. Our Industrial Affiliates, while very pleased with our graduates, requested that we produce some with greater mechanical engineering skills and knowledge. Our response was the creation of a new degree program, retaining the virtues of the previous one, but allowing a high degree of flexibility through the inclusion of minors within the program. The new program allows sufficient room for a variety of minors. Engineering minors identified include aerospace, computer, electrical, materials and mechanical. Science minors include astronomy, computer science, math and physics. Non-science minors accommodated include business, pre-health and pre-law. The new BSO program features: (1) Better structure and flow, more tightly coupling related classes; (2) New laboratory classes for juniors, linked to lecture classes; (3) Expanded optical deign, fabrication and testing classes; (4) New class in electronics for optics; (5) New classes in fiber optics and optical communications; (6) New capstone/senior project class for ABET compliance. This new BSO program will produce better entry-level optical scientists and engineers, and better candidates for graduate school. Our interactions with the external community will provide inputs concerning industrial needs, leading towards improved student counseling and program development. We will better serve national needs for skilled personnel in optics, and contribute even more to the optics workforce pipeline.

  6. The effect of participatory community communication on HIV preventive behaviors among ethnic minority youth in central Vietnam

    PubMed Central

    2012-01-01

    Background In Vietnam, socially marginalized groups such as ethnic minorities in mountainous areas are often difficult to engage in HIV research and prevention programs. This intervention study aimed to estimate the effect of participatory community communication (PCC) on changing HIV preventive ideation and behavior among ethnic minority youth in a rural district from central Vietnam. Methods In a cross-sectional survey after the PCC intervention, using a structured questionnaire, 800 ethnic minority youth were approached for face-to-face interviews. Propensity score matching (PSM) technique was then utilized to match these participants into two groups-intervention and control-for estimating the effect of the PCC. Results HIV preventive knowledge and ideation tended to increase as the level of recall changed accordingly. The campaign had a significant indirect effect on condom use through its effect on ideation or perceptions. When intervention and control group statistically equivalently reached in terms of individual and social characteristics by PSM, proportions of displaying HIV preventive knowledge, ideation and condom use were significantly higher in intervention group than in matched control counterparts, accounting for net differences of 7.4%, 12.7% and 5%, respectively, and can be translated into the number of 210; 361 and 142 ethnic minority youth in the population. Conclusions The study informs public health implications both theoretically and practically to guide effective HIV control programs for marginalized communities in resources-constrained settings like rural Vietnam and similar contexts of developing countries. PMID:22401660

  7. Strategies employed by sexual minority adolescents to cope with minority stress.

    PubMed

    Goldbach, J T; Gibbs, J J

    2015-09-01

    Sexual minority adolescents (SMA) experience disparities in health and behavioral health outcomes, including high rates of depression, anxiety, self-harm, substance use, HIV risk behavior, suicidal ideation, and suicide attempts. These outcomes are commonly attributed to minority stress. Stress experiences are different for SMA than their adult counterparts. For example, disclosing their sexual orientation may be more likely to result in homelessness because these youth more often live with parents or other family members. Although stress in this population has been explored in previous research, very little is known about how SMA cope. Relying upon an adolescent coping model, this study examined the coping strategies, responses, and resources of SMA related to stress. Forty-eight racially and ethnically diverse SMA (age 14-19) were recruited for 90-minute tape-recorded interviews. The semi-structured interviews were guided by a life history calendar. Recordings were transcribed verbatim and entered into QSR NVivo. All transcripts were coded by two members of the research team and went through a consensus process. Forty-three unique coping statements emerged that fit with the Compas model of adolescent coping. SMA cope with minority stress in similar ways to heterosexual youth coping with general stress, but findings suggest that SMA may also use different kinds of coping resources. Although further research is needed, the present study identified a variety of ways SMA cope with stress and can inform future research on the development interventions.

  8. Suicide risk in trans populations: An application of minority stress theory.

    PubMed

    Tebbe, Elliot A; Moradi, Bonnie

    2016-10-01

    Drawing on minority stress theory, the present study tested the relations of minority stressors (i.e., experiences of prejudice and discrimination, internalized antitrans attitudes, fear of antitrans stigma), social support (i.e., friend, family, and significant other support), and substance use (i.e., drug and alcohol use) with depression and suicide risk in a sample of trans individuals. Depression was examined as a mediator of the relations of minority stressors and social support with suicide risk; drug and alcohol use were examined as direct correlates of suicide risk. Participants were 335 trans-identified individuals, diverse in gender identities (e.g., trans men, trans women, nonbinary gender identities). They were recruited using online social networks and they completed the study survey online via Qualtrics. Structural equation modeling was used to test hypothesized relations. Depression fully mediated the relations of perceived experiences of discrimination, fear of antitrans stigma, and friend support with suicide risk, and partially mediated the relation of internalized antitrans attitudes with suicide. Drug use was positively associated with suicide risk, whereas alcohol use was not linked with suicide risk. Exploratory comparisons across gender subgroups suggested that the pattern of relations among study variables was consistent across trans men, trans women, and individuals with nonbinary gender identities. These findings point to minority stressors, friend support, and drug use as potentially fruitful targets of prevention and intervention efforts to reduce depression and suicide risk in trans populations. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  9. The California-Arizona Minority Partnership for Astronomy Research and Education (CAMPARE): Partnering Students to Astronomy at the University of Arizona's Astronomy Camp

    NASA Astrophysics Data System (ADS)

    Saldivar, Hector; McCarthy, D.; Rudolph, A. L.

    2012-01-01

    The California-Arizona Minority Partnership for Astronomy Research and Education (CAMPARE) is an NSF-funded partnership between the Astronomy Program at Cal Poly Pomona and the University of Arizona Steward Observatory designed to promote participation of underrepresented minorities, including women, in astronomy research and education. By means of this program, Cal Poly Pomona undergraduates that are either Physics majors or minors are qualified to participate in the program alongside graduate students from the University of Arizona as a camp counselor at the University of Arizona's Astronomy Camp, one of the elite astronomy programs worldwide. Students that participate in the CAMPARE program are granted an opportunity to work in a hands-on environment by teaching astronomy to students from all over the world in a highly structured environment. The CAMPARE student selected for this program in Summer 2011 worked under the supervision of Dr. Don McCarthy, professor at the University of Arizona and Astronomy Camp director for over 20 years, learning to lead a group of students through daily activities and ensure that the students are learning to their maximum potential. Through this experience, the CAMPARE student learned to capture students’ interest in astronomy and was introduced to real life teaching, which has helped prepare him for future experiences to come. We acknowledge the NSF for funding under Award No. AST-0847170, a PAARE Grant for the Calfornia-Arizona Minority Partnership for Astronomy Research and Education (CAMPARE).

  10. Validation of the Minority Stress Scale Among Italian Gay and Bisexual Men.

    PubMed

    Pala, Andrea Norcini; Dell'Amore, Francesca; Steca, Patrizia; Clinton, Lauren; Sandfort, Theodorus; Rael, Christine

    2017-12-01

    The experience of sexual orientation stigma (e.g., homophobic discrimination and physical aggression) generates minority stress, a chronic form of psychosocial stress. Minority stress has been shown to have a negative effect on gay and bisexual men's (GBM's) mental and physical health, increasing the rates of depression, suicidal ideation, and HIV risk behaviors. In conservative religious settings, such as Italy, sexual orientation stigma can be more frequently and/or more intensively experienced. However, minority stress among Italian GBM remains understudied. The aim of this study was to explore the dimensionality, internal reliability, and convergent validity of the Minority Stress Scale (MSS), a comprehensive instrument designed to assess the manifestations of sexual orientation stigma. The MSS consists of 50 items assessing (a) Structural Stigma, (b) Enacted Stigma, (c) Expectations of Discrimination, (d) Sexual Orientation Concealment, (e) Internalized Homophobia Toward Others, (f) Internalized Homophobia toward Oneself, and (g) Stigma Awareness. We recruited an online sample of 451 Italian GBM to take the MSS. We tested convergent validity using the Perceived Stress Questionnaire. Through exploratory factor analysis, we extracted the 7 theoretical factors and an additional 3-item factor assessing Expectations of Discrimination From Family Members. The MSS factors showed good internal reliability (ordinal α > .81) and good convergent validity. Our scale can be suitable for applications in research settings, psychosocial interventions, and, potentially, in clinical practice. Future studies will be conducted to further investigate the properties of the MSS, exploring the association with additional health-related measures (e.g., depressive symptoms and anxiety).

  11. Flaws in foldamers: conformational uniformity and signal decay in achiral helical peptide oligomers† †Electronic supplementary information (ESI) available: Synthesis and characterisation of all new compounds. See DOI: 10.1039/c4sc03944k Click here for additional data file.

    PubMed Central

    Le Bailly, Bryden A. F.; Byrne, Liam; Diemer, Vincent; Foroozandeh, Mohammadali; Morris, Gareth A.

    2015-01-01

    Although foldamers, by definition, are extended molecular structures with a well-defined conformation, minor conformers must be populated at least to some extent in solution. We present a quantitative analysis of these minor conformers for a series of helical oligomers built from achiral but helicogenic α-amino acids. By measuring the chain length dependence or chain position dependence of NMR or CD quantities that measure screw-sense preference in a helical oligomer, we quantify values for the decay constant of a conformational signal as it passes through the molecular structure. This conformational signal is a perturbation of the racemic mixture of M and P helices that such oligomers typically adopt by the inclusion of an N or C terminal chiral inducer. We show that decay constants may be very low (<1% signal loss per residue) in non-polar solvents, and we evaluate the increase in decay constant that results in polar solvents, at higher temperatures, and with more conformationally flexible residues such as Gly. Decay constants are independent of whether the signal originates from the N or the C terminus. By interpreting the decay constant in terms of the probability with which conformations containing a screw-sense reversal are populated, we quantify the populations of these alternative minor conformers within the overall ensemble of secondary structures adopted by the foldamer. We deduce helical persistence lengths for Aib polymers that allow us to show that in a non-polar solvent a peptide helix, even in the absence of chiral residues, may continue with the same screw sense for approximately 200 residues. PMID:29308146

  12. Effect of the interfacial O and Mg vacancies on electronic structure and transport properties of the FeRh/MgO/FeRh (0 0 1) magnetic tunnel junction: DFT calculations

    NASA Astrophysics Data System (ADS)

    Sakhraoui, T.; Said, M.

    2017-12-01

    The electronic, magnetic and transport properties of oxygen or magnesium vacancies at the FeRh/MgO/FeRh (0 0 1) magnetic tunnel junction are studied within first principles. Configurations with one O or Mg vacancy per C(2 × 2) surface unit cell, which is located in the MgO interfacial layers, are investigated. We observed that the O and Mg vacancies defect have a very little influence on the magnetic state of the spacer. Very interestingly, the Fe atoms exhibit an enhanced magnetic moment in the case of Mg-vacancy, this latter was found to decrease in the case of O-vacancy. The variations in the spin polarization and magnetic moment values for Fe and Rh atoms at the interface were found to be larger in presence of Mg vacancy. An analysis of the charge densities of our systems was also performed; large variations in the Mg-vacancy system were observed. This affects more the t2g states of the interfacial Fe atom. Moreover, we present an ab initio calculated transmission and I-V characteristics for FeRh/MgO/FeRh (0 0 1) magnetic tunnel junction and we compare results to those of O and Mg-vacancy at the interface using the TRANSIESTA code, which combines the DFT electronic structure calculations with the non-equilibrium Green function formalism (NEGF) for transport properties. The results show that the zero-bias minority spin transmission is much larger than the majority spin transmission for all structures. In all systems and for all magnetic configurations, minority spin currents are higher than majority spin ones, this means that transport properties are, mainly, determined by minority spin channel.

  13. Molecular mechanisms of conformational specificity: A study of Hox in vivo target DNA binding specificities and the structure of a Ure2p mutation that affects fibril formation rates

    NASA Astrophysics Data System (ADS)

    Bauer, William Joseph, Jr.

    The fate of an individual cell, or even an entire organism, is often determined by minute, yet very specific differences in the conformation of a single protein species. Very often, proteins take on alternate folds or even side chain conformations to deal with different situations present within the cell. These differences can be as large as a whole domain or as subtle as the alteration of a single amino acid side chain. Yet, even these seemingly minor side chain conformational differences can determine the development of a cell type during differentiation or even dictate whether a cell will live or die. Two examples of situations where minor conformational differences within a specific protein could lead to major differences in the life cycle of a cell are described herein. The first example describes the variations seen in DNA conformations which can lead to slightly different Hox protein binding conformations responsible for recognizing biologically relevant regulatory sites. These specific differences occur in the minor groove of the bound DNA and are limited to the conformation of only two side chains. The conformation of the bound DNA, however, is not solely determined by the sequence of the DNA, as multiple sequences can result in the same DNA conformation. The second example takes place in the context of a yeast prion protein which contains a mutation that decreases the frequency at which fibrils form. While the specific interactions leading to this physiological change were not directly detected, it can be ascertained from the crystal structure that the structural changes are subtle and most likely involve another binding partner. In both cases, these conformational changes are very slight but have a profound effect on the downstream processes.

  14. Do arterial stiffness and wave reflection underlie cardiovascular risk in ethnic minorities?

    PubMed

    Faconti, Luca; Nanino, Elisa; Mills, Charlotte E; Cruickshank, Kennedy J

    2016-01-01

    Increasing evidence indicates that remarkable differences in cardiovascular risk between ethnic groups cannot be fully explained by traditional risk factors such as hypertension, diabetes or dislipidemia measured in midlife. Therefore, the underlying pathophysiology leading to this "excess risk" in ethnic minority groups is still poorly understood, and one way to address this issue is to shift the focus from "risk" to examine target organs, particularly blood vessels and their arterial properties more directly. In fact, structural and functional changes of the vascular system may be identifiable at very early stages of life when traditional factors are not yet developed. Arterial stiffening, measured as aortic pulse wave velocity, and wave reflection parameters, especially augmentation index, seem to be an important pathophysiological mechanism for the development of cardiovascular disease and predict mortality independent of other risk factors. However, data regarding these arterial indices in ethnic minorities are relatively rare and the heterogeneity between populations, techniques and statistical methods make it difficult to fully understand their role.

  15. Conceptualization of Sexual Partner Relationship Steadiness Among Ethnic Minority Adolescent Women: Implications for Evidence-Based Behavioral Sexual Risk Reduction Interventions

    PubMed Central

    Champion, Jane Dimmitt; Collins, Jennifer L.

    2012-01-01

    Cognitive behavioral interventions for sexual risk reduction have been less successful among ethnic minority adolescent women with histories of abuse and sexually transmitted infections (STI) than among other adolescent populations. African American and Mexican American adolescent women (ages 14–18 years, n = 548) self-reported sexual partner relationship steadiness and sexual risk behaviors via semi-structured interviews at study entry. Descriptive and bivariate analyses compared sexual risk behaviors by sexual partner relationship steadiness. Steady and unsteady relationships were conceptualized differently. Steady relationships included emotional or financial support, sexual communication, greater relationship importance, unintended pregnancy, and perceived monogamy during break-ups. Unsteady relationships were unpredictable, including sex with ex-steady partners and friends with benefits, lack of mutual respect, and poor sexual communication. Modification of sexual risk reduction interventions including conceptualizations of risk by context of sexual partner relationship status is recommended to enhance efficacy among minority adolescent women with STI or history of abuse. PMID:22868248

  16. Flight service evaluation of Kevlar-49 epoxy composite panels in wide-bodies commercial transport aircraft

    NASA Technical Reports Server (NTRS)

    Stone, R. H.

    1983-01-01

    Kevlar-49 fairing panels, installed as flight service components on three L-1011s, were inspected after 9 years of service. There are six Kevlar-49 panels on each aircraft: a left hand and right hand set of a wing body sandwich fairing; a solid laminate under wing fillet panel; and a 422 K (300 F) service aft engine fairing. The fairings have accumulated a total of 70,000 hours, with one ship set having over 24,000 hours service. The Kevlar-49 components were found to be performing satisfactorily in service with no major problems, or any condition requiring corrective action. The only defects noted were minor impact damage, a few minor disbonds and a minor degree of fastener hole fraying and elongation. These are for the most part comparable to damage noted on fiberglass fairings. The service history to date indicates that Kevlar-49 epoxy composite materials have satisfactory service characteristics for use in aircraft secondary structure.

  17. An exploratory model of girls' vulnerability to commercial sexual exploitation in prostitution.

    PubMed

    Reid, Joan A

    2011-05-01

    Due to inaccessibility of child victims of commercial sexual exploitation, the majority of emergent research on the problem lacks theoretical framing or sufficient data for quantitative analysis. Drawing from Agnew's general strain theory, this study utilized structural equation modeling to explore: whether caregiver strain is linked to child maltreatment, if experiencing maltreatment is associated with risk-inflating behaviors or sexual denigration of self/others, and if these behavioral and psychosocial dysfunctions are related to vulnerability to commercial sexual exploitation. The proposed model was tested with data from 174 predominately African American women, 12% of whom indicated involvement in prostitution while a minor. Findings revealed child maltreatment worsened with increased caregiver strain. Experiencing child maltreatment was linked to running away, initiating substance use at earlier ages, and higher levels of sexual denigration of self/others. Sexual denigration of self/others was significantly related to the likelihood of prostitution as a minor. The network of variables in the model accounted for 34% of the variance in prostitution as a minor.

  18. Breaking up is hard to do: Women's experience of dissolving their same-sex relationship.

    PubMed

    Balsam, Kimberly F; Rostosky, Sharon S; Riggle, Ellen D B

    2017-01-02

    While prior research has compared same-sex to heterosexual relationships, very little attention has been paid to the unique experiences of women dissolving same-sex relationships, especially in the context of shifting legal and social policies. The current study examined the experience of 20 women who dissolved their same-sex relationship between 2002 and 2014. Participants were drawn from a longitudinal sample of same-sex and heterosexual couples and were interviewed using a semi-structured protocol. Interviews focused on three primary research questions: reasons for dissolution, emotional reactions, and role of legal status. While reasons for dissolution largely mirrored literature on women in heterosexual relationships, emotional reactions and the role of legal status were both influenced by sexual minority-specific factors related to minority stress and the recent societal changes pertaining to legal relationship recognition. Results are interpreted in a framework of minority stress and the ongoing legacy of institutional discrimination experienced by women in same-sex relationships.

  19. Components and context: exploring sources of reading difficulties for language minority learners and native English speakers in urban schools.

    PubMed

    Kieffer, Michael J; Vukovic, Rose K

    2012-01-01

    Drawing on the cognitive and ecological domains within the componential model of reading, this longitudinal study explores heterogeneity in the sources of reading difficulties for language minority learners and native English speakers in urban schools. Students (N = 150) were followed from first through third grade and assessed annually on standardized English language and reading measures. Structural equation modeling was used to investigate the relative contributions of code-related and linguistic comprehension skills in first and second grade to third grade reading comprehension. Linguistic comprehension and the interaction between linguistic comprehension and code-related skills each explained substantial variation in reading comprehension. Among students with low reading comprehension, more than 80% demonstrated weaknesses in linguistic comprehension alone, whereas approximately 15% demonstrated weaknesses in both linguistic comprehension and code-related skills. Results were remarkably similar for the language minority learners and native English speakers, suggesting the importance of their shared socioeconomic backgrounds and schooling contexts.

  20. Sexual and Gender Diversity within the Black Men who have Sex with Men HIV Epidemiological Category

    PubMed Central

    Wilson, Bianca D.M.; Miyashita, Ayako

    2016-01-01

    Epidemiological categories not only reflect existing frameworks for public health, but reify how subpopulations are defined, understood, and targeted for interventions. The sweeping categorization of Black men who have sex with men (BMSM) used in HIV research and intervention work is one such example. The current paper builds upon previous critiques of the “MSM” nomenclature by delineating the sexual and gender diversity embedded in the term as it pertains specifically to Black peoples. The emphasis is on developing greater specificity about the sociocultural and structural factors that may be shared among these subgroups, such as racism and poverty, and the factors that are likely to distinguish the groups, such as levels of sexual minority identification, access to lesbian, gay, bisexual, and transgender (LGBT) services and community, and experiences with anti-bisexual or anti-transgender bias. The aim then is to provide a framework for HIV health policy work for Black sexual minority cisgender men (SMCM) and gender minorities (GM). PMID:27525047

  1. Sexual and Gender Diversity within the Black Men who have Sex with Men HIV Epidemiological Category.

    PubMed

    Wilson, Bianca D M; Miyashita, Ayako

    2016-09-01

    Epidemiological categories not only reflect existing frameworks for public health, but reify how subpopulations are defined, understood, and targeted for interventions. The sweeping categorization of Black men who have sex with men (BMSM) used in HIV research and intervention work is one such example. The current paper builds upon previous critiques of the "MSM" nomenclature by delineating the sexual and gender diversity embedded in the term as it pertains specifically to Black peoples. The emphasis is on developing greater specificity about the sociocultural and structural factors that may be shared among these subgroups, such as racism and poverty, and the factors that are likely to distinguish the groups, such as levels of sexual minority identification, access to lesbian, gay, bisexual, and transgender (LGBT) services and community, and experiences with anti-bisexual or anti-transgender bias. The aim then is to provide a framework for HIV health policy work for Black sexual minority cisgender men (SMCM) and gender minorities (GM).

  2. An optimized algorithm for multiscale wideband deconvolution of radio astronomical images

    NASA Astrophysics Data System (ADS)

    Offringa, A. R.; Smirnov, O.

    2017-10-01

    We describe a new multiscale deconvolution algorithm that can also be used in a multifrequency mode. The algorithm only affects the minor clean loop. In single-frequency mode, the minor loop of our improved multiscale algorithm is over an order of magnitude faster than the casa multiscale algorithm, and produces results of similar quality. For multifrequency deconvolution, a technique named joined-channel cleaning is used. In this mode, the minor loop of our algorithm is two to three orders of magnitude faster than casa msmfs. We extend the multiscale mode with automated scale-dependent masking, which allows structures to be cleaned below the noise. We describe a new scale-bias function for use in multiscale cleaning. We test a second deconvolution method that is a variant of the moresane deconvolution technique, and uses a convex optimization technique with isotropic undecimated wavelets as dictionary. On simple well-calibrated data, the convex optimization algorithm produces visually more representative models. On complex or imperfect data, the convex optimization algorithm has stability issues.

  3. Intragroup Contact and Anxiety Among Ethnic Minority Adolescents: Considering Ethnic Identity and School Diversity Transitions

    PubMed Central

    Yip, Tiffany; Shelton, J. Nicole

    2015-01-01

    Everyday interactions with same-racial/ethnic others may confer positive benefits for adolescents, but the meaning of these interactions are likely influenced by individual differences and larger structural contexts. This study examined the situation-level association between contact with same-ethnic others and anxiety symptoms among a diverse sample of 306 racial/ethnic minority adolescents (Mage = 14 years; 66 % female), based on (1) individual differences in ethnic identity centrality and (2) developmental histories of transitions in diversity between elementary, middle, and high school. The results indicated that at the level of the situation, when adolescents interacted with more same-ethnic others, they reported fewer anxiety symptoms. Further, for adolescents who had experienced a transition in school diversity, the positive benefits of contact with same-ethnic others was only conferred for those who felt that their ethnicity was very important to them. The importance of examining individual differences within larger developmental histories to understand the everyday experiences of ethnic minority adolescents are discussed. PMID:24951944

  4. Sexual Orientation Differences in Health and Wellbeing Among Women Living with HIV in Canada: Findings from a National Cohort Study.

    PubMed

    Logie, Carmen H; Lacombe-Duncan, Ashley; Wang, Ying; Kaida, Angela; de Pokomandy, Alexandra; Webster, Kath; Conway, Tracey; Loutfy, Mona

    2018-06-01

    Sexual orientation differences in health and wellbeing among women living with HIV (WLH) are underexplored. Limited research available, however, suggests that sexual minority WLH may experience barriers to HIV care. Cross-sectional baseline data was analyzed from a Canadian cohort study with WLH (sexual minority women [SMW]: n = 180; heterosexual women: n = 1240). SMW (median age 38 years, IQR 13) included bisexual (58.9%), lesbian (17.8%) and other sexualities (23.3%). In multivariable analyses adjusting for age, poverty, education, and ethnicity, SMW identity was associated with increased odds of: clinical (80% vs. 100% antiretroviral adherence), intrapersonal (previous/current injection drug use [IDU] vs. no IDU history, depression, lower resilience), interpersonal (childhood abuse, sex work, adulthood abuse), and structural (HIV support services barriers, unstable housing, racial discrimination, gender discrimination) factors in comparison with heterosexual identity. Sexual minority WLH experience social and health disparities relative to heterosexual WLH, highlighting the need for interventions to promote health equity.

  5. Optimization of the Surface Structure on Black Silicon for Surface Passivation

    NASA Astrophysics Data System (ADS)

    Jia, Xiaojie; Zhou, Chunlan; Wang, Wenjing

    2017-03-01

    Black silicon shows excellent anti-reflection and thus is extremely useful for photovoltaic applications. However, its high surface recombination velocity limits the efficiency of solar cells. In this paper, the effective minority carrier lifetime of black silicon is improved by optimizing metal-catalyzed chemical etching (MCCE) method, using an Al2O3 thin film deposited by atomic layer deposition (ALD) as a passivation layer. Using the spray method to eliminate the impact on the rear side, single-side black silicon was obtained on n-type solar grade silicon wafers. Post-etch treatment with NH4OH/H2O2/H2O mixed solution not only smoothes the surface but also increases the effective minority lifetime from 161 μs of as-prepared wafer to 333 μs after cleaning. Moreover, adding illumination during the etching process results in an improvement in both the numerical value and the uniformity of the effective minority carrier lifetime.

  6. A New Stress-Based Model of Political Extremism: Personal Exposure to Terrorism, Psychological Distress, and Exclusionist Political Attitudes.

    PubMed

    Canetti-Nisim, Daphna; Halperin, Eran; Sharvit, Keren; Hobfoll, Stevan E

    2009-06-01

    Does exposure to terrorism lead to hostility toward minorities? Drawing on theories from clinical and social psychology, we propose a stress-based model of political extremism in which psychological distress-which is largely overlooked in political scholarship-and threat perceptions mediate the relationship between exposure to terrorism and attitudes toward minorities. To test the model, a representative sample of 469 Israeli Jewish respondents was interviewed on three occasions at six-month intervals. Structural Equation Modeling indicated that exposure to terrorism predicted psychological distress (t1), which predicted perceived threat from Palestinian citizens of Israel (t2), which, in turn, predicted exclusionist attitudes toward Palestinian citizens of Israel (t3). These findings provide solid evidence and a mechanism for the hypothesis that terrorism introduces nondemocratic attitudes threatening minority rights. It suggests that psychological distress plays an important role in political decision making and should be incorporated in models drawing upon political psychology.

  7. Visual Similarity of Words Alone Can Modulate Hemispheric Lateralization in Visual Word Recognition: Evidence From Modeling Chinese Character Recognition.

    PubMed

    Hsiao, Janet H; Cheung, Kit

    2016-03-01

    In Chinese orthography, the most common character structure consists of a semantic radical on the left and a phonetic radical on the right (SP characters); the minority, opposite arrangement also exists (PS characters). Recent studies showed that SP character processing is more left hemisphere (LH) lateralized than PS character processing. Nevertheless, it remains unclear whether this is due to phonetic radical position or character type frequency. Through computational modeling with artificial lexicons, in which we implement a theory of hemispheric asymmetry in perception but do not assume phonological processing being LH lateralized, we show that the difference in character type frequency alone is sufficient to exhibit the effect that the dominant type has a stronger LH lateralization than the minority type. This effect is due to higher visual similarity among characters in the dominant type than the minority type, demonstrating the modulation of visual similarity of words on hemispheric lateralization. Copyright © 2015 Cognitive Science Society, Inc.

  8. Optimization of the Surface Structure on Black Silicon for Surface Passivation.

    PubMed

    Jia, Xiaojie; Zhou, Chunlan; Wang, Wenjing

    2017-12-01

    Black silicon shows excellent anti-reflection and thus is extremely useful for photovoltaic applications. However, its high surface recombination velocity limits the efficiency of solar cells. In this paper, the effective minority carrier lifetime of black silicon is improved by optimizing metal-catalyzed chemical etching (MCCE) method, using an Al 2 O 3 thin film deposited by atomic layer deposition (ALD) as a passivation layer. Using the spray method to eliminate the impact on the rear side, single-side black silicon was obtained on n-type solar grade silicon wafers. Post-etch treatment with NH 4 OH/H 2 O 2 /H 2 O mixed solution not only smoothes the surface but also increases the effective minority lifetime from 161 μs of as-prepared wafer to 333 μs after cleaning. Moreover, adding illumination during the etching process results in an improvement in both the numerical value and the uniformity of the effective minority carrier lifetime.

  9. Two-dimensional particle-in-cell plasma source ion implantation of a prolate spheroid target

    NASA Astrophysics Data System (ADS)

    Liu, Cheng-Sen; Han, Hong-Ying; Peng, Xiao-Qing; Chang, Ye; Wang, De-Zhen

    2010-03-01

    A two-dimensional particle-in-cell simulation is used to study the time-dependent evolution of the sheath surrounding a prolate spheroid target during a high voltage pulse in plasma source ion implantation. Our study shows that the potential contour lines pack more closely in the plasma sheath near the vertex of the major axis, i.e. where a thinner sheath is formed, and a non-uniform total ion dose distribution is incident along the surface of the prolate spheroid target due to the focusing of ions by the potential structure. Ion focusing takes place not only at the vertex of the major axis, where dense potential contour lines exist, but also at the vertex of the minor axis, where sparse contour lines exist. This results in two peaks of the received ion dose, locating at the vertices of the major and minor axes of the prolate spheroid target, and an ion dose valley, staying always between the vertices, rather than at the vertex of the minor axis.

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meagher, Martin; Enemark, Eric J.

    The crystal structure of the N-terminal domain of thePyrococcus furiosusminichromosome maintenance (MCM) protein as a double hexamer is described. The MCM complex is a ring-shaped helicase that unwinds DNA at the replication fork of eukaryotes and archaea. Prior to replication initiation, the MCM complex assembles as an inactive double hexamer at specific sites of DNA. The presented structure is highly consistent with previous MCM double-hexamer structures and shows two MCM hexamers with a head-to-head interaction mediated by the N-terminal domain. Minor differences include a diminished head-to-head interaction and a slightly reduced inter-hexamer rotation.

  11. Conductive ceramic composition and method of preparation

    DOEpatents

    Smith, J.L.; Kucera, E.H.

    1991-04-16

    A ceramic anode composition is formed of a multivalent metal oxide or oxygenate such as an alkali metal, transition metal oxygenate. The anode is prepared as a non-stoichiometric crystalline structure by reaction and conditioning in a hydrogen gas cover containing minor proportions of carbon dioxide and water vapor. The structure exhibits a single phase and substantially enhanced electrical conductivity over that of the corresponding stoichiometric structure. Unexpectedly, such oxides and oxygenates are found to be stable in the reducing anode fuel gas of a molten carbonate fuel cell. 4 figures.

  12. Conductive ceramic composition and method of preparation

    DOEpatents

    Smith, James L.; Kucera, Eugenia H.

    1991-01-01

    A ceramic anode composition is formed of a multivalent metal oxide or oxygenate such as an alkali metal, transition metal oxygenate. The anode is prepared as a non-stoichiometric crystalline structure by reaction and conditioning in a hydrogen gas cover containing minor proportions of carbon dioxide and water vapor. The structure exhibits a single phase and substantially enhanced electrical conductivity over that of the corresponding stoichiometric structure. Unexpectedly, such oxides and oxygenates are found to be stable in the reducing anode fuel gas of a molten carbonate fuel cell.

  13. Adhesion by pathogenic corynebacteria.

    PubMed

    Rogers, Elizabeth A; Das, Asis; Ton-That, Hung

    2011-01-01

    Pathogenic members of the genus Corynebacterium cause a wide range of serious infections in humans including diphtheria. Adhesion to host cells is a crucial step during infection. In Corynebacterium diphtheriae, adhesion is mediated primarily by filamentous structures called pili or fimbriae that are covalently attached to the bacterial cell wall. C. diphtheriae produces three distinct pilus structures, SpaA-, SpaD- and SpaH-type pili. Similar to other types, the prototype SpaA pilus consists of SpaA forming the pilus shaft and two minor pilins SpaB and SpaC located at the base and at the tip, respectively. The minor pilins SpaB/SpaC are critical for bacterial binding to human pharyngeal cells, and thus represent the major adhesins of corynebacteria. Like pili of many other gram-positive microbes, the assembly of corynebacterial pili occurs by a two-step mechanism, whereby pilins are covalently polymerized by a transpeptidase enzyme named pilin-specific sortase and the generated pilus polymer is subsequently anchored to the cell wall peptidoglycan via the base pilin by the housekeeping sortase or a non-polymerizing sortase. This chapter reviews the current knowledge of corynebacterial adhesion, with a specific focus on pilus structures, their assembly, and the mechanism of adhesion mediated by pili.

  14. Evolutionary insight into the functional amyloids of the pseudomonads.

    PubMed

    Dueholm, Morten S; Otzen, Daniel; Nielsen, Per Halkjær

    2013-01-01

    Functional bacterial amyloids (FuBA) are important components in many environmental biofilms where they provide structural integrity to the biofilm, mediate bacterial aggregation and may function as virulence factor by binding specifically to host cell molecules. A novel FuBA system, the Fap system, was previously characterized in the genus Pseudomonas, however, very little is known about the phylogenetic diversity of bacteria with the genetic capacity to apply this system. Studies of genomes and public metagenomes from a diverse range of habitats showed that the Fap system is restricted to only three classes in the phylum Proteobacteria, the Beta-, Gamma- and Deltaproteobacteria. The structural organization of the fap genes into a single fapABCDEF operon is well conserved with minor variations such as a frequent deletion of fapA. A high degree of variation was seen within the primary structure of the major Fap fibril monomers, FapC, whereas the minor monomers, FapB, showed less sequence variation. Comparison of phylogenetic trees based on Fap proteins and the 16S rRNA gene of the corresponding bacteria showed remarkably similar overall topology. This indicates, that horizontal gene transfer is an infrequent event in the evolution of the Fap system.

  15. Evolutionary Insight into the Functional Amyloids of the Pseudomonads

    PubMed Central

    Dueholm, Morten S.; Otzen, Daniel; Nielsen, Per Halkjær

    2013-01-01

    Functional bacterial amyloids (FuBA) are important components in many environmental biofilms where they provide structural integrity to the biofilm, mediate bacterial aggregation and may function as virulence factor by binding specifically to host cell molecules. A novel FuBA system, the Fap system, was previously characterized in the genus Pseudomonas, however, very little is known about the phylogenetic diversity of bacteria with the genetic capacity to apply this system. Studies of genomes and public metagenomes from a diverse range of habitats showed that the Fap system is restricted to only three classes in the phylum Proteobacteria, the Beta-, Gamma- and Deltaproteobacteria. The structural organization of the fap genes into a single fapABCDEF operon is well conserved with minor variations such as a frequent deletion of fapA. A high degree of variation was seen within the primary structure of the major Fap fibril monomers, FapC, whereas the minor monomers, FapB, showed less sequence variation. Comparison of phylogenetic trees based on Fap proteins and the 16S rRNA gene of the corresponding bacteria showed remarkably similar overall topology. This indicates, that horizontal gene transfer is an infrequent event in the evolution of the Fap system. PMID:24116129

  16. Feelings about culture scales: development, factor structure, reliability, and validity.

    PubMed

    Maffini, Cara S; Wong, Y Joel

    2015-04-01

    Although measures of cultural identity, values, and behavior exist in the multicultural psychological literature, there is currently no measure that explicitly assesses ethnic minority individuals' positive and negative affect toward culture. Therefore, we developed 2 new measures called the Feelings About Culture Scale--Ethnic Culture and Feelings About Culture Scale--Mainstream American Culture and tested their psychometric properties. In 6 studies, we piloted the measures, conducted factor analyses to clarify their factor structure, and examined reliability and validity. The factor structure revealed 2 dimensions reflecting positive and negative affect for each measure. Results provided evidence for convergent, discriminant, criterion-related, and incremental validity as well as the reliability of the scales. The Feelings About Culture Scales are the first known measures to examine both positive and negative affect toward an individual's ethnic culture and mainstream American culture. The focus on affect captures dimensions of psychological experiences that differ from cognitive and behavioral constructs often used to measure cultural orientation. These measures can serve as a valuable contribution to both research and counseling by providing insight into the nuanced affective experiences ethnic minority individuals have toward culture. (c) 2015 APA, all rights reserved).

  17. 33 CFR 203.83 - Additional requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... deteriorated components such as outlet structures and pipes, removal of debris, and new construction items such... furnishing flood fight assistance during an emergency. (b) Areas of minor damage, flood control works..., placing sod, or seeding completed work. (d) Adequacy of requirements of local cooperation. In determining...

  18. Closing the Gaps. Research Brief

    ERIC Educational Resources Information Center

    Johnston, Howard

    2011-01-01

    Achievement gaps between groups of students (minority and white, rich and poor, English speakers and English language learners) are complex and intractable. Increasingly, they are being seen as a result of disparities between opportunities for learning available to different groups. By changing the opportunity structures of schools and…

  19. 77 FR 6128 - National Institute of General Medical Sciences Notice of Closed Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-07

    ... Sciences Special Emphasis Panel; Review of application for High- Throughput-Enabled Structural Biology..., Cell Biology and Biophysics Research; 93.859, Pharmacology, Physiology, and Biological Chemistry Research; 93.862, Genetics and Developmental Biology Research; 93.88, Minority Access to Research Careers...

  20. Reimagining publics and (non)participation: Exploring exclusion from science communication through the experiences of low-income, minority ethnic groups.

    PubMed

    Dawson, Emily

    2018-01-01

    This article explores science communication from the perspective of those most at risk of exclusion, drawing on ethnographic fieldwork. I conducted five focus groups and 32 interviews with participants from low-income, minority ethnic backgrounds. Using theories of social reproduction and social justice, I argue that participation in science communication is marked by structural inequalities (particularly ethnicity and class) in two ways. First, participants' involvement in science communication practices was narrow (limited to science media consumption). Second, their experiences of exclusion centred on cultural imperialism (misrepresentation and 'Othering') and powerlessness (being unable to participate or change the terms of their participation). I argue that social reproduction in science communication constructs a narrow public that reflects the shape, values and practices of dominant groups, at the expense of the marginalised. The article contributes to how we might reimagine science communication's publics by taking inclusion/exclusion and the effects of structural inequalities into account.

  1. Thermal stability of photovoltaic a-Si:H determined by neutron reflectometry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Qviller, A. J., E-mail: atlejq@ife.no; Haug, H.; You, C. C.

    2014-12-08

    Neutron and X-ray reflectometry were used to determine the layer structure and hydrogen content of thin films of amorphous silicon (a-Si:H) deposited onto crystalline silicon (Si) wafers for surface passivation in solar cells. The combination of these two reflectometry techniques is well suited for non-destructive probing of the structure of a-Si:H due to being able to probe buried interfaces and having sub-nanometer resolution. Neutron reflectometry is also unique in its ability to allow determination of density gradients of light elements such as hydrogen (H). The neutron scattering contrast between Si and H is strong, making it possible to determine themore » H concentration in the deposited a-Si:H. In order to correlate the surface passivation properties supplied by the a-Si:H thin films, as quantified by obtainable effective minority carrier lifetime, photoconductance measurements were also performed. It is shown that the minority carrier lifetime falls sharply when H has been desorbed from a-Si:H by annealing.« less

  2. Structural hysteresis in dragline spider silks induced by supercontraction: an X-ray fiber micro-diffraction study

    DOE PAGES

    Sampath, Sujatha; Yarger, Jeffery L.

    2014-11-27

    Interaction with water causes shrinkage and significant changes in the structure of spider dragline silks, which has been referred to as supercontraction in the literature. Preferred orientation or alignment of protein chains with respect to the fiber axis is extensively changed during this supercontraction process. Synchrotron X-ray micro-fiber diffraction experiments have been performed on Nephila clavipes and Argiope aurantia major and minor ampullate dragline spider fibers in the native dry, contracted (by immersion in water) and restretched (from contracted) states. Changes in the orientation of β-sheet nanocrystallites and the oriented component of the amorphous network have been determined from wide-anglemore » X-ray diffraction patterns. While both the crystalline and amorphous components lose preferred orientation on wetting with water, the nano-crystallites regain their orientation on wet-restretching, whereas the oriented amorphous components only partially regain their orientation. Dragline major ampullate silks in both the species contract more than their minor ampullate silks.« less

  3. Stigma, sexual health, and human rights among women who have sex with women in Lesotho

    PubMed Central

    Poteat, Tonia C.; Logie, Carmen H.; Adams, Darrin; Mothopeng, Tampose; Lebona, Judith; Letsie, Puleng; Baral, Stefan

    2016-01-01

    In recent years, gender and sexual minorities have become increasingly visible across sub-Saharan Africa, marking both the progression and violation of their human rights. Using data from a study with sexual minorities in Lesotho, this analysis leveraged the social ecological model to examine relationships between stigma, human rights, and sexual health among women who have sex with women in Lesotho. A community-based participatory approach was used for the mixed-method, cross-sectional study. A total of 250 women who have sex with women completed a structured questionnaire, of which 21 participated in a total of three focus group discussions. Stigma was common within and outside the health sector. Stigma and human rights abuses were associated with increased risk for HIV and STIs. Interventions to address stigma at the structural, community, and interpersonal levels are essential to ensuring sexual health and rights for women who have sex with women in Lesotho. PMID:26719002

  4. Characterization of high-quality kerfless epitaxial silicon for solar cells: Defect sources and impact on minority-carrier lifetime

    DOE PAGES

    Kivambe, Maulid M.; Powell, Douglas M.; Castellanos, Sergio; ...

    2017-11-14

    We investigate the types and origins of structural defects in thin (<100 μm) kerfless epitaxial single crystal silicon grown on top of reorganized porous silicon layers. Although the structural defect density is low (has average defect density < 10 4 cm -2), localized areas with a defect density > 10 5 cm -2 are observed. Cross-sectional and systematic plan-view defect etching and microscopy reveals that the majority of stacking faults and dislocations originate at the interface between the porous silicon layer and the epitaxial wafer. Localised dislocation clusters are observed in regions of collapsed/deformed porous silicon and at decorated stackingmore » faults. In localized regions of high extended defect density, increased minority-carrier recombination activity is observed. Evidence for impurity segregation to the extended defects (internal gettering), which is known to exacerbate carrier recombination is demonstrated. In conclusion, the impact of the defects on material performance and substrate re-use is also discussed.« less

  5. Three-dimensional minority-carrier collection channels at shunt locations in silicon solar cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guthrey, Harvey; Johnston, Steve; Weiss, Dirk N.

    2016-10-01

    In this contribution, we demonstrate the value of using a multiscale multi-technique characterization approach to study the performance-limiting defects in multi-crystalline silicon (mc-Si) photovoltaic devices. The combination of dark lock-in thermography (DLIT) imaging, electron beam induced current imaging, and both transmission and scanning transmission electron microscopy (TEM/STEM) on the same location revealed the nanoscale origin of the optoelectronic properties of shunts visible at the device scale. Our site-specific correlative approach identified the shunt behavior to be a result of three-dimensional inversion channels around structural defects decorated with oxide precipitates. These inversion channels facilitate enhanced minority-carrier transport that results in themore » increased heating observed through DLIT imaging. The definitive connection between the nanoscale structure and chemistry of the type of shunt investigated here allows photovoltaic device manufacturers to immediately address the oxygen content of their mc-Si absorber material when such features are present, instead of engaging in costly characterization.« less

  6. Willy: A prize noble Ur-Fremdling - Its history and implications for the formation of Fremdlinge and CAI

    NASA Technical Reports Server (NTRS)

    Armstrong, J. T.; El Goresy, A.; Wasserburg, G. J.

    1985-01-01

    The structure and composition of Willy, a 150-micron-diameter Fremdling in CAI 5241 from the Allende meteorite, are investigated using optical, secondary-electron, and electron-backscatter microscopy and electron-microprobe analysis. The results are presented in diagrams, maps, tables, graphs, and micrographs and compared with those for other Allende Fremdlinge. Willy is found to have a concentric-zone structure comprising a complex porous core of magnetite, metal, sulfide, scheelite, and other minor phases; a compact magnetite-apatite mantle; a thin (20 microns or less) reaction-assemblage zone; and a dense outer rim of fassaite with minor spinel. A multistage formation sequence involving changes in T and fO2 and preceding the introduction of Willy into the CAI (which itself preceded CAI spinel and silicate formation) is postulated, and it is inferred from the apparent lack of post-capture recrystallization that Willy has not been subjected to temperatures in excess of 600 C and may represent the precursor material for many other Fremdlinge.

  7. Stigma, sexual health, and human rights among women who have sex with women in Lesotho.

    PubMed

    Poteat, Tonia C; Logie, Carmen H; Adams, Darrin; Mothopeng, Tampose; Lebona, Judith; Letsie, Puleng; Baral, Stefan

    2015-11-01

    In recent years, gender and sexual minorities have become increasingly visible across sub-Saharan Africa, marking both the progression and violation of their human rights. Using data from a study with sexual minorities in Lesotho, this analysis leveraged the social ecological model to examine relationships between stigma, human rights, and sexual health among women who have sex with women in Lesotho. A community-based participatory approach was used for the mixed-method, cross-sectional study. A total of 250 women who have sex with women completed a structured questionnaire, of which 21 participated in a total of three focus group discussions. Stigma was common within and outside the health sector. Stigma and human rights abuses were associated with increased risk for HIV and STIs. Interventions to address stigma at the structural, community, and interpersonal levels are essential to ensuring sexual health and rights for women who have sex with women in Lesotho. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Characterization of high-quality kerfless epitaxial silicon for solar cells: Defect sources and impact on minority-carrier lifetime

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kivambe, Maulid M.; Powell, Douglas M.; Castellanos, Sergio

    We investigate the types and origins of structural defects in thin (<100 μm) kerfless epitaxial single crystal silicon grown on top of reorganized porous silicon layers. Although the structural defect density is low (has average defect density < 10 4 cm -2), localized areas with a defect density > 10 5 cm -2 are observed. Cross-sectional and systematic plan-view defect etching and microscopy reveals that the majority of stacking faults and dislocations originate at the interface between the porous silicon layer and the epitaxial wafer. Localised dislocation clusters are observed in regions of collapsed/deformed porous silicon and at decorated stackingmore » faults. In localized regions of high extended defect density, increased minority-carrier recombination activity is observed. Evidence for impurity segregation to the extended defects (internal gettering), which is known to exacerbate carrier recombination is demonstrated. In conclusion, the impact of the defects on material performance and substrate re-use is also discussed.« less

  9. Characterization of high-quality kerfless epitaxial silicon for solar cells: Defect sources and impact on minority-carrier lifetime

    NASA Astrophysics Data System (ADS)

    Kivambe, Maulid M.; Powell, Douglas M.; Castellanos, Sergio; Jensen, Mallory Ann; Morishige, Ashley E.; Lai, Barry; Hao, Ruiying; Ravi, T. S.; Buonassisi, Tonio

    2018-02-01

    We investigate the types and origins of structural defects in thin (<100 μm) kerfless epitaxial single crystal silicon grown on top of reorganized porous silicon layers. Although the structural defect density is low (has average defect density < 104 cm-2), localized areas with a defect density > 105 cm-2 are observed. Cross-sectional and systematic plan-view defect etching and microscopy reveals that the majority of stacking faults and dislocations originate at the interface between the porous silicon layer and the epitaxial wafer. Localised dislocation clusters are observed in regions of collapsed/deformed porous silicon and at decorated stacking faults. In localized regions of high extended defect density, increased minority-carrier recombination activity is observed. Evidence for impurity segregation to the extended defects (internal gettering), which is known to exacerbate carrier recombination is demonstrated. The impact of the defects on material performance and substrate re-use is also discussed.

  10. Mechanism of Origin DNA Recognition and Assembly of an Initiator-Helicase Complex by SV40 Large Tumor Antigen

    PubMed Central

    Chang, Y. Paul; Xu, Meng; Machado, Ana Carolina Dantas; Yu, Xian Jessica; Rohs, Remo; Chen, Xiaojiang S.

    2013-01-01

    SUMMARY The DNA tumor virus Simian virus 40 (SV40) is a model system for studying eukaryotic replication. SV40 large tumor antigen (LTag) is the initiator/helicase that is essential for genome replication. LTag recognizes and assembles at the viral replication origin. We determined the structure of two multidomain LTag subunits bound to origin DNA. The structure reveals that the origin binding domains (OBDs) and Zn and AAA+ domains are involved in origin recognition and assembly. Notably, the OBDs recognize the origin in an unexpected manner. The histidine residues of the AAA+ domains insert into a narrow minor groove region with enhanced negative electrostatic potential. Computational analysis indicates that this region is intrinsically narrow, demonstrating the role of DNA shape readout in origin recognition. Our results provide important insights into the assembly of the LTag initiator/ helicase at the replication origin and suggest that histidine contacts with the minor groove serve as a mechanism of DNA shape readout. PMID:23545501

  11. Onset of mandible and tibia osteoradionecrosis – a comparative pilot study in the rat

    PubMed Central

    Damek-Poprawa, Monika; Both, Stefan; Wright, Alexander C.; Maity, Amit; Akintoye, Sunday O.

    2012-01-01

    Objectives Osteoradionecrosis (ORN) is common in the jaws following radiotherapy. We hypothesized that mandible is more susceptible to ORN than tibia based on site-disparity in hypoxic-hypocellular-hypovascular tissue breakdown. Study Design Twelve rats received 50 Gy irradiation to mandible or tibia; 4 of 12 rats further received minor surgical trauma to the irradiated sites. Structural and cellular skeletal changes were assessed with computer tomography, histology and immunostaining. Results Mandible developed ORN with 70% mean bone loss 10 weeks post-irradiation (p < 0.05) while tibia was structurally and radiological intact for 20 weeks post-irradiation. Hypocellularity, hypoxia and oxidative stress were higher in irradiated mandible (p < 0.001) than tibia (p < 0.01) but vascular damage was similar at both skeletal sites. Combined effects of radiation and minor trauma promoted mandibular alveolar bone loss and tibial fracture Conclusion ORN has a more rapid onset in mandible relative to tibia in the rat PMID:23254371

  12. Exploring the spiral of silence in adjustable social networks

    NASA Astrophysics Data System (ADS)

    Wu, Yue; Du, Ya-Jun; Li, Xian-Yong; Chen, Xiao-Liang

    2015-03-01

    This study extends the understanding of the spiral of silence theory by taking into account four factors, including the topology of networks, the time factor of information transmission, the node degree of individuals and the freedom of expression. Simulation experiments analyze the silencers, public opinion in steady state and relaxation time in small-world networks, scale-free networks and community-structured networks by adjusting the initial conditions. Results highlight that individuals are easier to keep silent in scale-free network, especially when the individual with big degree and minority opinion starts the discussion. Conversely, there are only a few individuals keep silent in the community-structured network when the two communities hold opposite opinions. Moreover, the number of silencers grows as the degree of coupling increases, and it decreases as the freedom of expression goes up. By analyzing the public opinion evolution, we also find some important conditions, such as the network topology, the potential public opinion distribution, and the status and sides of the first speaker, can drive the minority reversal.

  13. Near Field Imaging of Charge Transport in Gallium Nitride and Zinc Oxide Nanostructures

    DTIC Science & Technology

    2010-12-01

    distribution of recombination luminescence . While researching the diffusion lengths of these structures, the author also observed that many of these... diffusion length of these structures can be extracted. E. NEAR FIELD IMAGING WITH NEAR FIELD SCANNING OPTICAL MICROSCOPY Near field scanning optical...composite AFM/NSOM images and the slope analysis to extract Ld, the minority carrier diffusion length , as described in Chapter 3. In all cases, excitation

  14. Electronic structures of U X3 (X =Al , Ga, and In) studied by photoelectron spectroscopy

    NASA Astrophysics Data System (ADS)

    Fujimori, Shin-ichi; Kobata, Masaaki; Takeda, Yukiharu; Okane, Tetsuo; Saitoh, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; Ōnuki, Yoshichika

    2017-09-01

    The electronic structures of U X3 (X =Al , Ga , and In ) were studied by photoelectron spectroscopy to understand the relationship between their electronic structures and magnetic properties. The band structures and Fermi surfaces of UAl3 and UGa3 were revealed experimentally by angle-resolved photoelectron spectroscopy (ARPES), and they were compared with the result of band-structure calculations. The topologies of the Fermi surfaces and the band structures of UAl3 and UGa3 were explained reasonably well by the calculation, although bands near the Fermi level (EF) were renormalized owing to the finite electron correlation effect. The topologies of the Fermi surfaces of UAl3 and UGa3 are very similar to each other, except for some minor differences. Such minor differences in their Fermi surface or electron correlation effect might take an essential role in their different magnetic properties. No significant changes were observed between the ARPES spectra of UGa3 in the paramagnetic and antiferromagnetic phases, suggesting that UGa3 is an itinerant weak antiferromagnet. The effect of chemical pressure on the electronic structures of U X3 compounds was also studied by utilizing the smaller lattice constants of UAl3 and UGa3 than that of UIn3. The valence band spectrum of UIn3 is accompanied by a satellitelike structure on the high-binding-energy side. The core-level spectrum of UIn3 is also qualitatively different from those of UAl3 and UGa3. These findings suggest that the U 5 f states in UIn3 are more localized than those in UAl3 and UGa3.

  15. The Mediating Roles of Rejection Sensitivity and Proximal Stress in the Association Between Discrimination and Internalizing Symptoms Among Sexual Minority Women.

    PubMed

    Dyar, Christina; Feinstein, Brian A; Eaton, Nicholas R; London, Bonita

    2018-01-01

    The negative impact of discrimination on mental health among lesbian, gay, and bisexual populations has been well documented. However, the possible mediating roles of sexual orientation rejection sensitivity and rejection-based proximal stress in the association between discrimination and internalizing symptoms remain unclear. Rejection-based proximal stress is a subset of proximal stressors that are theorized to arise from concerns about and expectations of sexual orientation-based rejection and discrimination. Drawing on minority stress theory, we tested potential mediating effects using indirect effects structural equation modeling in a sample of 300 sexual minority women. Results indicated that the indirect effect of discrimination on internalizing symptoms (a latent variable indicated by depression and anxiety symptoms) through sexual orientation rejection sensitivity and rejection-based proximal stress (a latent variable indicated by preoccupation with stigma, concealment motivation, and difficulty developing a positive sexual identity) was significant. Additionally, the indirect effects of discrimination on rejection-based proximal stress through sexual orientation rejection sensitivity and of sexual orientation rejection sensitivity on internalizing symptoms through rejection-based proximal stress were also significant. These findings indicate that sexual orientation rejection sensitivity plays an important role in contributing to rejection-based proximal stress and internalizing symptoms among sexual minority women.

  16. Space-charge limited current in CdTe thin film solar cell

    NASA Astrophysics Data System (ADS)

    Li, Qiang; Shen, Kai; Li, Xun; Yang, Ruilong; Deng, Yi; Wang, Deliang

    2018-04-01

    In this study, we demonstrate that space-charge limited current (SCLC) is an intrinsic current shunting leakage in CdTe thin film solar cells. The SCLC leakage channel, which is formed by contact between the front electrode, CdTe, and the back electrode, acts as a metal-semiconductor-metal (MSM) like transport path. The presence of SCLC leaking microchannels in CdTe leads to a band bending at the MSM structure, which enhances minority carrier recombination and thus decreases the minority carrier lifetime in CdTe thin film solar cells. SCLC was found to be a limiting factor both for the fill factor and the open-circuit voltage of CdTe thin film solar cells.

  17. Paleokarst processes in the Eocene limestones of the Pyramids Plateau, Giza, Egypt

    NASA Astrophysics Data System (ADS)

    El Aref, M. M.; Refai, E.

    The Eocene limestones of the Pyramids plateau are characterized by landforms of stepped terraced escarpment and karst ridges with isolated hills. The carbonate country rocks are also dominated by minor surface, surface to subsurface and subsurface solution features associated with karst products. The systematic field observations eludicate the denudation trend of the minor solution features and suggest the origin of the regional landscapes. The lithologic and structural characters of the limestone country rocks comprise the main factors controlling the surface and subsurface karst evolution. The development of the karst features and the associated sediments in the study area provides information on the paleohydrolic, chemical and climatic environments involved in the origin of the karstification.

  18. Haitians: A Neglected Minority

    ERIC Educational Resources Information Center

    Seligman, Linda

    1977-01-01

    Haitians have been found to respond well to client-centered group counseling and to be able to use that structure to deal with personal, social, and vocational difficulties. Counseling with Haitians can be particularly gratifying because of their motivation for self-help and their willingness to become involved in counseling. (Author)

  19. VIVA LA SALUD INFANTILE: Pediatric obesity treatment in an underserved Hispanic community

    USDA-ARS?s Scientific Manuscript database

    Pediatric obesity in the US disproportionately impacts minority populations who face socioeconomic and cultural barriers to weight management programs. The specific aim of this pilot study was to test the effectiveness of diet behavior modification or diet behavior modification plus structured aerob...

  20. Social Justice and Evidence-Based Assessment with the Learning Record

    ERIC Educational Resources Information Center

    Syverson, Margaret A.

    2009-01-01

    The educational system perpetuates social injustice through structural inequities of assessment and evaluation. High-stakes standardized testing has a destructive effect on teaching and learning that affects all students, teachers, and schools; it is particularly damaging for disadvantaged students--minorities, students with disabilities, students…

  1. Stacking Up

    ERIC Educational Resources Information Center

    Naylor, Jim

    2005-01-01

    Chimneys and stacks appear to be strong and indestructible, but chimneys begin to deteriorate from the moment they are built. Early on, no signs are apparent; but deterioration accelerates in subsequent years, and major repairs are soon needed instead of minor maintenance. With proper attention, most structures can be repaired and continue to…

  2. 76 FR 62080 - National Institute of General Medical Sciences; Notice of Closed Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-06

    ... Sciences Special Emphasis Panel, Review of Applications for High- Throughput-Enabled Structural Biology... Support; 93.821, Cell Biology and Biophysics Research; 93.859, Pharmacology, Physiology, and Biological Chemistry Research; 93.862, Genetics and Developmental Biology Research; 93.88, Minority Access to Research...

  3. Learning Communities: A Structure for Educational Coherence.

    ERIC Educational Resources Information Center

    Matthews, Roberta; And Others

    1996-01-01

    College and university learning communities build a sense of group identity. Institutions are establishing them for varied purposes and student populations, including first-year interest groups, general education core courses, gateway courses, developmental and basic studies, honors programs, and work in the major or minor. For implementation,…

  4. Determination of lipid bilayer affinities and solvation characteristics by electrokinetic chromatography using polymer-bound lipid bilayer nanodiscs.

    PubMed

    Penny, William M; Palmer, Christopher P

    2018-03-01

    Styrene-maleic acid polymer-bound lipid bilayer nanodiscs have been investigated and characterized by electrokinetic chromatography. Linear solvation energy relationship analysis was employed to characterize the changes in solvation environment of nanodiscs of varied belt to lipid ratio, belt polymer chemistry and molecular weight, and lipid composition. Increases in the lipid to belt polymer ratio resulted in smaller, more cohesive nanodiscs with greater electrophoretic mobility. Nanodisc structures with belt polymers of different chemistry and molecular weight were compared and showed only minor changes in solvent characteristics and selectivity consistent with changes in structure of the lipid bilayer. Seven phospholipid and sphingomyelin nanodiscs of different lipid composition were characterized. Changes in lipid head group structure had a significant effect on bilayer-solute interactions. In most cases, changes in alkyl tail structure had no discernible effect on solvation environment aside from those explained by changes in the gel-liquid transition temperature. Comparison to vesicles of similar lipid composition show only minor differences in solvation environment, likely due to differences in lipid composition and bilayer curvature. Together these results provide evidence that the dominant solute-nanodisc interactions are with the lipid bilayer and that head group chemistry has a greater impact on bilayer-solute interactions than alkyl tail or belt polymer structure. Nanodisc electrokinetic chromatography is demonstrated to allow characterization of solute interactions with lipid bilayers of varied composition. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Orbital frustration induced unusual ordering in semiconductor alloys

    NASA Astrophysics Data System (ADS)

    Liu, Kai; Yin, Wanjian; Chen, Shiyou; Gong, Xingao; Wei, Suhuai; Xiang, Hongjun

    It is well known that ternary zinc-blende semiconductors are always more stable in the chalcopyrite (CH) structure than the Cu-Au (CA) structure because CH structure has large Coulomb interaction and reduced strain energy. Surprisingly, an experimental study showed that ZnFeSe2 alloy takes the CA order as the ground state structure, which is consistent with our density function theory (DFT) calculations showing that the CA order has lower energy than the CH order for ZnFeSe2. We reveal that the orbital degree of freedom of high-spin Fe2+ ion (d6) in the tetrahedral crystal field plays a key role in stabilizing the CA order. First, the spin-minority d electron of the Fe2+ ion tends to occupy the dx2-y 2 -like orbital instead of the d3z2 -r2 -like orbital because of its large negative Coulomb energy. Second, for a nearest-neighboring Fe2+ pair, two spin-minority d electrons with occupied dx2-y 2 -like orbitals in the plane containing the Fe-Fe bond has lower electronic kinetic energy. Both conditions can be satisfied in the CA ordered ZnFeSe2 alloy, while there is an orbital frustration in the CH structure. Our results suggest that orbital degree of freedom provides a new way to manipulate the structure and properties of alloys. Work at Fudan was supported by NSFC (11374056), the Special Funds for Major State Basic Research (2012CB921400, 2015CB921700), Program for Professor of Special Appointment (Eastern Scholar), and Fok Ying Tung Education Foundation.

  6. Dual-phase Cr-Ta alloys for structural applications

    DOEpatents

    Liu, Chain T.; Brady, Michael P.; Zhu, Jiahong; Tortorelli, Peter F.

    2001-01-01

    Dual phase alloys of chromium containing 2 to 11 atomic percent tantalum with minor amounts of Mo, Cr, Ti, Y, La, Cr, Si and Ge are disclosed. These alloys contain two phases including Laves phase and Cr-rich solid solution in either eutectic structures or dispersed Laves phase particles in the Cr-rich solid solution matrix. The alloys have superior mechanical properties at high temperature and good oxidation resistance when heated to above 1000.degree. C. in air.

  7. STS-26 solid rocket booster post flight structural assessment

    NASA Technical Reports Server (NTRS)

    Herda, David A.; Finnegan, Charles J.

    1988-01-01

    A post flight assessment of the Space Shuttle's Solid Rocket Boosters was conducted at the John F. Kennedy Space Center in Florida after the launch of STS-26. The two boosters were inspected for structural damage and the results of this inspection are presented. Overall, the boosters were in good condition. However, there was some minor damage attributed to splash down. Some of this damage is a recurring problem. Explanations of these problems are provided.

  8. Definitive Mineralogical Analysis of Martian Rocks and Soil Using the CheMin XRD/XRF Instrument and the USDC Sampler

    NASA Technical Reports Server (NTRS)

    Blake, D. F.; Sarrazin, P.; Chipera, S. J.; Bish, D. L.; Vaniman, D. T.; Bar-Cohen, Y.; Sherrit, S.; Collins, S.; Boyer, B.; Bryson, C.

    2003-01-01

    The search for evidence of extant or extinct life on Mars will initially be a search for evidence of present or past conditions supportive of life (e.g., evidence of water), not for life itself. Definitive evidence of past or present water activity lies in the discovery of: * Hydrated minerals: The "rock type" hosting the hydrated minerals could be igneous, metamorphic, or sedimentary, with only a minor hydrated mineral phase. Therefore, the identification of minor phases is important. * Clastic sediments: Clastic sediments are commonly identified by the fact that they contain minerals of disparate origin that could only have come together as a mechanical mixture. Therefore, the identification of all minerals present in a mixture to ascertain mineralogical source regions is important. * Hydrothermal precipitates and chemical sediments: Some chemical precipitates are uniquely identified only by their structure. For example, Opal A, Opal CT, tridymite, crystobalite, high and low Quartz all have the same composition (SiO2) but different crystal structures indicative of different environments - from hydrothermal hydrothermal formation to low temperature precipitation. Other silica types such as stishovite can provide evidence of shock metamorphism. Therefore, identification of crystal structures and structural polymorphs is important. The elucidation of the nature of the Mars soil will require the identification of mineral components that can unravel its history and the history of the Mars atmosphere.

  9. Modeling of DNA local parameters predicts encrypted architectural motifs in Xenopus laevis ribosomal gene promoter.

    PubMed

    Roux-Rouquie, M; Marilley, M

    2000-09-15

    We have modeled local DNA sequence parameters to search for DNA architectural motifs involved in transcription regulation and promotion within the Xenopus laevis ribosomal gene promoter and the intergenic spacer (IGS) sequences. The IGS was found to be shaped into distinct topological domains. First, intrinsic bends split the IGS into domains of common but different helical features. Local parameters at inter-domain junctions exhibit a high variability with respect to intrinsic curvature, bendability and thermal stability. Secondly, the repeated sequence blocks of the IGS exhibit right-handed supercoiled structures which could be related to their enhancer properties. Thirdly, the gene promoter presents both inherent curvature and minor groove narrowing which may be viewed as motifs of a structural code for protein recognition and binding. Such pre-existing deformations could simply be remodeled during the binding of the transcription complex. Alternatively, these deformations could pre-shape the promoter in such a way that further remodeling is facilitated. Mutations shown to abolish promoter curvature as well as intrinsic minor groove narrowing, in a variant which maintained full transcriptional activity, bring circumstantial evidence for structurally-preorganized motifs in relation to transcription regulation and promotion. Using well documented X. laevis rDNA regulatory sequences we showed that computer modeling may be of invaluable assistance in assessing encrypted architectural motifs. The evidence of these DNA topological motifs with respect to the concept of structural code is discussed.

  10. Impact of primer dimers and self-amplifying hairpins on reverse transcription loop-mediated isothermal amplification detection of viral RNA

    DOE PAGES

    Meagher, Robert J.; Priye, Aashish; Light, Yooli K.; ...

    2018-03-27

    Loop-mediated isothermal amplification (LAMP), coupled with reverse transcription (RT), has become a popular technique for detection of viral RNA due to several desirable characteristics for use in point-of-care or low-resource settings. The large number of primers in LAMP (six per target) leads to an increased likelihood of primer-dimer interactions, and the inner primers in particular are prone to formation of stable hairpin structures due to their length (typically 40-45 bases). Although primer-dimers and hairpin structures are known features to avoid in nucleic acid amplification techniques, there is little quantitative information in literature regarding the impact of these structures on LAMPmore » or RT-LAMP assays. In this study, we examine the impact of primer-dimers and hairpins on previously-published primer sets for dengue virus and yellow fever virus. We demonstrate that minor changes to the primers to eliminate amplifiable primer dimers and hairpins improves the performance of the assays when monitored in real time with intercalating dyes, and when monitoring a fluorescent endpoint using the QUASR technique. We also discuss the thermodynamic implications of these minor changes on the overall stability of amplifiable secondary structures, and we present a single thermodynamic parameter to predict the probability of non-specific amplification associated with LAMP primers.« less

  11. Impact of primer dimers and self-amplifying hairpins on reverse transcription loop-mediated isothermal amplification detection of viral RNA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meagher, Robert J.; Priye, Aashish; Light, Yooli K.

    Loop-mediated isothermal amplification (LAMP), coupled with reverse transcription (RT), has become a popular technique for detection of viral RNA due to several desirable characteristics for use in point-of-care or low-resource settings. The large number of primers in LAMP (six per target) leads to an increased likelihood of primer-dimer interactions, and the inner primers in particular are prone to formation of stable hairpin structures due to their length (typically 40-45 bases). Although primer-dimers and hairpin structures are known features to avoid in nucleic acid amplification techniques, there is little quantitative information in literature regarding the impact of these structures on LAMPmore » or RT-LAMP assays. In this study, we examine the impact of primer-dimers and hairpins on previously-published primer sets for dengue virus and yellow fever virus. We demonstrate that minor changes to the primers to eliminate amplifiable primer dimers and hairpins improves the performance of the assays when monitored in real time with intercalating dyes, and when monitoring a fluorescent endpoint using the QUASR technique. We also discuss the thermodynamic implications of these minor changes on the overall stability of amplifiable secondary structures, and we present a single thermodynamic parameter to predict the probability of non-specific amplification associated with LAMP primers.« less

  12. Music is Beneficial for Awake Craniotomy Patients: A Qualitative Study.

    PubMed

    Jadavji-Mithani, Radhika; Venkatraghavan, Lashmi; Bernstein, Mark

    2015-01-01

    Patients undergoing awake craniotomy may experience high levels of stress. Minimizing anxiety benefits patients and surgeons. Music has many therapeutic effects in altering human mood and emotion. Tonality of music as conveyed by composition in major or minor keys can have an impact on patients' emotions and thoughts. Assessing the effects of listening to major and minor key musical pieces on patients undergoing awake craniotiomy could help in the design of interventions to alleviate anxiety, stress and tension. Twenty-nine patients who were undergoing awake craniotomy were recruited and randomly assigned into two groups: Group 1 subjects listened to major key music and Group 2 listened to minor key compositions. Subjects completed a demographics questionnaire, a pre- and post-operative Beck Anxiety Inventory (BAI) and a semi-structured open-ended interview. RESULTS were analyzed using modified thematic analysis through open and axial coding. Overall, patients enjoyed the music regardless of the key distinctions and stated they benefitted from listening to the music. No adverse reactions to the music were found. Subjects remarked that the music made them feel more at ease and less anxious before, during and after their procedure. Patients preferred either major key or minor key music but not a combination of both. Those who preferred major key pieces said it was on the basis of tonality while the individuals who selected minor key pieces stated that tempo of the music was the primary factor. Overall, listening to music selections was beneficial for the patients. Future work should further investigate the effects of audio interventions in awake surgery through narrative means.

  13. Cost-effectiveness of an activating intervention by social workers for patients with minor mental disorders on sick leave: a randomized controlled trial.

    PubMed

    Brouwers, Evelien P M; de Bruijne, Martine C; Terluin, Berend; Tiemens, Bea G; Verhaak, Peter F M

    2007-04-01

    Sickness absence often occurs in patients with emotional distress or minor mental disorders. In several European countries, these patients are over-represented among those receiving illness benefits, and interventions are needed. The aim of this study was to evaluate the cost-effectiveness of an intervention conducted by social workers, designed to reduce sick leave duration in patients absent from work owing to emotional distress or minor mental disorders. In this Randomized Controlled Trial, patients were recruited by GPs. The intervention group (N = 98) received an activating, structured treatment by social workers, the control group (N = 96) received routine GP care. Sick leave duration, clinical symptoms, and medical consumption (consumption of medical staffs' time as well as consumption of drugs) were measured at baseline and 3, 6, and 18 months later. Neither for sick leave duration nor for clinical improvement over time were significant differences found between the groups. Also the associated costs were not significantly lower in the intervention group. Compared with usual GP care, the activating social work intervention was not superior in reducing sick leave duration, improving clinical symptoms, and decreasing medical consumption. It was also not cost-effective compared with GP routine care in the treatment of minor mental disorders. Therefore, further implementation of the intervention is not justified. Potentially, programmes aimed at reducing sick leave duration in patients with minor mental disorders carried out closer to the workplace (e.g. by occupational physicians) are more successful than programmes in primary care.

  14. Evidence of Syndemics and Sexuality-Related Discrimination Among Young Sexual-Minority Women.

    PubMed

    Coulter, Robert W S; Kinsky, Suzanne M; Herrick, Amy L; Stall, Ron D; Bauermeister, José A

    2015-09-01

    Syndemics, or the co-occurrence and interaction of health problems, have been examined extensively among young men who have sex with men, but their existence remain unexamined, to our knowledge, among sexual-minority (i.e., lesbian, gay, and bisexual) women. Thus, we investigated if syndemics were present among young sexual-minority women, and if sexual-orientation discrimination was an independent variable of syndemic production. A total of 467 sexual-minority women between the ages of 18 and 24 completed a cross-sectional online survey regarding their substance use, mental health, sexual behaviors, height, weight, and experiences of discrimination. We used structural equation modeling to investigate the presence of syndemics and their relationship to sexual-orientation discrimination. Heavy episodic drinking, marijuana use, ecstasy use, hallucinogen use, depressive symptoms, multiple sexual partners, and history of sexually transmitted infections (STIs) comprised syndemics in this population (chi-square=24.989, P=.201; comparative fit index [CFI]=0.946; root mean square error of approximation [RMSEA]=0.023). Sexual-orientation discrimination is significantly and positively associated with the latent syndemic variable (unstandardized coefficient=0.095, P<.05), and this model fit the data well (chi-square=33.558, P=.059; CFI=0.914; RMSEA=0.029). The reverse causal model showed syndemics is not an independent variable of sexual-orientation discrimination (unstandardized coefficient=0.602, P>.05). Syndemics appear to be present and associated with sexual-orientation discrimination among young sexual-minority women. Interventions aimed at reducing discrimination or increasing healthy coping may help reduce substance use, depressive symptoms, and sexual risk behaviors in this population.

  15. Validation of the Minority Stress Scale Among Italian Gay and Bisexual Men

    PubMed Central

    Pala, Andrea Norcini; Dell’Amore, Francesca; Steca, Patrizia; Clinton, Lauren; Sandfort, Theodorus; Rael, Christine

    2017-01-01

    The experience of sexual orientation stigma (e.g., homophobic discrimination and physical aggression) generates minority stress, a chronic form of psychosocial stress. Minority stress has been shown to have a negative effect on gay and bisexual men’s (GBM’s) mental and physical health, increasing the rates of depression, suicidal ideation, and HIV risk behaviors. In conservative religious settings, such as Italy, sexual orientation stigma can be more frequently and/or more intensively experienced. However, minority stress among Italian GBM remains understudied. The aim of this study was to explore the dimensionality, internal reliability, and convergent validity of the Minority Stress Scale (MSS), a comprehensive instrument designed to assess the manifestations of sexual orientation stigma. The MSS consists of 50 items assessing (a) Structural Stigma, (b) Enacted Stigma, (c) Expectations of Discrimination, (d) Sexual Orientation Concealment, (e) Internalized Homophobia Toward Others, (f) Internalized Homophobia toward Oneself, and (g) Stigma Awareness. We recruited an online sample of 451 Italian GBM to take the MSS. We tested convergent validity using the Perceived Stress Questionnaire. Through exploratory factor analysis, we extracted the 7 theoretical factors and an additional 3-item factor assessing Expectations of Discrimination From Family Members. The MSS factors showed good internal reliability (ordinal α > .81) and good convergent validity. Our scale can be suitable for applications in research settings, psychosocial interventions, and, potentially, in clinical practice. Future studies will be conducted to further investigate the properties of the MSS, exploring the association with additional health-related measures (e.g., depressive symptoms and anxiety). PMID:29479555

  16. Dating violence, quality of life and mental health in sexual minority populations: a path analysis.

    PubMed

    Wong, Janet Yuen-Ha; Choi, Edmond Pui-Hang; Lo, Herman Hay-Ming; Wong, Wendy; Chio, Jasmine Hin-Man; Choi, Anna Wai-Man; Fong, Daniel Yee-Tak

    2017-04-01

    Theories explaining the impact of intimate partner violence (IPV) on mental health have focused on heterosexual relationships. It is unclear whether mental health disparities between heterosexual and sexual minority people are due to IPV or factors related to sexual orientation. The present study aimed to investigate pathways of how sexual orientation influenced quality of life and mental health. The present cross-sectional study was conducted in 1076 young adults in a university population (934 heterosexual and 142 sexual minority groups). Structural equation modelling was used to examine the pathways of sexual orientation, dating violence, sexual orientation concealment, quality of life and mental health (perceived stress, anxiety and depression). After adjusting for sociodemographic factors, quality of life in sexual minority people was poorer [estimate -2.82, 95 % confidence interval (CI) -4.77 to -0.86, p = 0.005], and stress (estimate 2.77, 95 % CI 1.64-3.92, p < 0.0001), anxiety (estimate 1.84, 95 % CI 1.13-2.56, p < 0.0001) and depression levels (estimate 0.62, 95 % CI 0.05-1.2, p < 0.0001) were higher than in heterosexual people. Dating violence and sexual orientation concealment were mediators, with the models showing a good fit. Our study has progressed investigation of the link between sexual orientation and quality of life and mental health in the Chinese context. It has helped identify health disparities between heterosexual and sexual minority people and determined specific factors affecting their quality of life and mental health.

  17. Understanding parenting concerns in cancer survivors with minor and young-adult children.

    PubMed

    Inhestern, Laura; Bultmann, Johanna Christine; Beierlein, Volker; Möller, Birgit; Romer, Georg; Koch, Uwe; Bergelt, Corinna

    2016-08-01

    Parents with cancer are concerned about the impact of their disease on their children. However, parenting concerns and associated factors in cancer survivors have not previously been analyzed. The purpose of this study is to examine parenting concerns and to test a path model for understanding parenting concerns in cancer survivors. In a cross-sectional study, a total of 1416 parents with cancer (mean age 47.5years, 74% women) having minor or young-adult children were recruited through two cancer registries. Parenting concerns were assessed using the Parenting Concerns Questionnaire. Structural equation modeling (SEM) was used to analyze the associations between social support, parenting confidence, emotional distress, family functioning and parenting concerns. Mothers reported higher total parenting concerns than fathers (p<0.001). We observed strong effects of emotional distress and parenting confidence on parenting concerns. Family dysfunctioning was associated with lower concerns. An indirect association between social support and parenting concerns was identified. Parenting concerns in cancer survivors display the need for interventions and after care programs that focus on affected families with minor and young adult children. The results of the structural path model illustrate the associations between psychological and interactional factors. Supporting parents with cancer in their parenting confidence and strengthen social support and family functioning may not only reduce the long-term burden on the parents themselves but also the burden on the entire family. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. New structures and composition of cell wall teichoic acids from Nocardiopsis synnemataformans, Nocardiopsis halotolerans, Nocardiopsis composta and Nocardiopsis metallicus: a chemotaxonomic value.

    PubMed

    Tul'skaya, Elena M; Shashkov, Alexander S; Streshinskaya, Galina M; Potekhina, Natalia V; Evtushenko, Ludmila I

    2014-12-01

    The structures of the cell wall teichoic acids (TA) from some species of the genus Nocardiopsis were established by chemical and NMR spectroscopic methods. The cell walls of Nocardiopsis synnemataformans VKM Ac-2518(T) and Nocardiopsis halotolerans VKM Ac-2519(T) both contain two TA with unique structures-poly(polyol phosphate-glycosylpolyol phosphate)-belonging to the type IV TA. In both organisms, the minor TA have identical structures: poly(glycerol phosphate-N-acetyl-β-galactosaminylglycerol phosphate) with the phosphodiester bond between C-3 of glycerol and C-4 of the amino sugar. This structure is found for the first time. The major TA of N. halotolerans has a hitherto unknown structure: poly(glycerol phosphate-N-acetyl-β-galactosaminylglycerol phosphate), the N-acetyl-β-galactosamine being acetalated with pyruvic acid at positions 4 and 6. The major TA of N. synnemataformans is a poly(glycerol phosphate-N-acetyl-β-galactosaminylglycerol phosphate) with the phosphodiester bond between C-3 of glycerol and C-3 of the amino sugar. The cell walls of Nocardiopsis composta VKM Ac-2520 and N. composta VKM Ac-2521(T) contain only one TA, namely 1,3-poly(glycerol phosphate) partially substituted with N-acetyl-α-glucosamine. The cell wall of Nocardiopsis metallicus VKM Ac-2522(T) contains two TA. The major TA is 1,5-poly(ribitol phosphate), each ribitol unit carrying a pyruvate ketal group at positions 2 and 4. The structure of the minor TA is the same as that of N. composta. The results presented correlate well with the phylogenetic grouping of strains and confirm the species and strain specific features of cell wall TA in members of the genus Nocardiopsis.

  19. Race and Gender Differences in Undergraduate Research Mentoring Structures and Research Outcomes.

    PubMed

    Aikens, Melissa L; Robertson, Melissa M; Sadselia, Sona; Watkins, Keiana; Evans, Mara; Runyon, Christopher R; Eby, Lillian T; Dolan, Erin L

    2017-01-01

    Participating in undergraduate research with mentorship from faculty may be particularly important for ensuring the persistence of women and minority students in science. Yet many life science undergraduates at research universities are mentored by graduate or postdoctoral researchers (i.e., postgraduates). We surveyed a national sample of undergraduate life science researchers about the mentoring structure of their research experiences and the outcomes they realized from participating in research. We observed two common mentoring structures: an open triad with undergraduate-postgraduate and postgraduate-faculty ties but no undergraduate-faculty tie, and a closed triad with ties among all three members. We found that men and underrepresented minority (URM) students are significantly more likely to report a direct tie to their faculty mentors (closed triad) than women, white, and Asian students. We also determined that mentoring structure was associated with differences in student outcomes. Women's mentoring structures were associated with their lower scientific identity, lower intentions to pursue a science, technology, engineering, and mathematics (STEM) PhD, and lower scholarly productivity. URM students' mentoring structures were associated with higher scientific identity, greater intentions to pursue a STEM PhD, and higher scholarly productivity. Asian students reported lower scientific identity and intentions to pursue a STEM PhD, which were unrelated to their mentoring structures. © 2017 M. L. Aikens et al. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  20. Negotiating Potentials and Limitations in Education in Transnational Migration Contexts: A Case Study

    ERIC Educational Resources Information Center

    Chamakalayil, Lalitha; Riegel, Christine

    2016-01-01

    Education systems reproduce social inequality based on social class, gender, and minority ethnicity ascriptions, and are organized along national structures. This paper explores, how migration and international mobility shape an individuals scope of possibilities in the context of education. We analyze how societal and institutional possibilities…

  1. Evaluation and the Framing of Race

    ERIC Educational Resources Information Center

    House, Ernest R.

    2017-01-01

    Racial framing can have strong effects on programs, policies, and even evaluations. Racial framing developed as a justification for the exploitation of minorities and has been a primary causal factor in the persistence of racism. By being aware of its pattern, structure, origins, and how racial framing generates effects, we can significantly…

  2. Adaptive Physical Education: Instructional Module for Special Education Minors.

    ERIC Educational Resources Information Center

    Smyser, Sheryl; And Others

    This module is designed to familiarize students preparing to be special education teachers with the physical needs of the exceptional student. Information is given on how to structure an adaptive physical education program designed to meet those needs, including development of an individualized education program (IEP). The module covers such…

  3. Psychological Pathways from Financial Conditions to Outcomes for Youth

    ERIC Educational Resources Information Center

    Destin, Mesmin P.

    2010-01-01

    Low-income and minority youth are dramatically less likely to reach a college education than their higher income and White counterparts. The dissertation evaluates how socioeconomic circumstances and family assets come to influence academic motivation and lifetime outcomes for youth. In chapter II, structural equation models, constructed from…

  4. History of early bridge specifications : a reprint of a paper by J. N. Clary.

    DOT National Transportation Integrated Search

    2006-01-01

    This report is a reprint of an informed review of the specifications for iron and steel bridges, both railroad and highway structures, dating from the mid-19th through the early 20th centuries. It is reprinted with only minor editing as a companion t...

  5. The Future of Our Organizations: Students and Early Career Professionals

    ERIC Educational Resources Information Center

    Yakushko, Oksana; Wang, Sherry C.; Warrior, Anitra M.

    2012-01-01

    This response focuses on the significance of ethnic minority psychology organizations and other related membership structures to early career psychologists (ECPs) and counseling psychology students. We discuss not only reasons for why students and ECPs may not be joining professional organizations, but also strategies for recruiting, supporting,…

  6. Autonomy and Relatedness in Inner-City Families of Substance Abusing Adolescents

    ERIC Educational Resources Information Center

    Samuolis, Jessica; Hogue, Aaron; Dauber, Sarah; Liddle, Howard A.

    2006-01-01

    This study examined parent-adolescent autonomous-relatedness functioning in inner-city, ethnic minority families of adolescents exhibiting drug abuse and related problem behaviors. Seventy-four parent-adolescent dyads completed a structured interaction task prior to the start of treatment that was coded using an established autonomous-relatedness…

  7. The Public School Monopoly: A Critical Analysis of Education and the State in American Society.

    ERIC Educational Resources Information Center

    Everhart, Robert B., Ed.

    The following 14 essays consider relationships among schooling, education, and the state; alternatives to existing systems; and educating minorities and the disadvantaged: (1) "Growing Up Blighted: Reflections on the 'Secret Power' in the American Experience" (C. Burgess); (2) "The Evolving Political Structure of American…

  8. Wood products : thermal degradation and fire

    Treesearch

    R.H. White; M.A. Dietenberger

    2001-01-01

    Wood is a thermally degradable and combustible material. Applications range from a biomass providing useful energy to a building material with unique properties. Wood products can contribute to unwanted fires and be destroyed as well. Minor amounts of thermal degradation adversely affect structural properties. Therefore, knowledge of the thermal degradation and fire...

  9. 36 CFR 18.12 - What specific provisions must a lease contain?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... to lessee activities; (h) Appropriate provisions stating that the lessee has no rights of renewal of..., minor additions, buildings and/or structures determined by the Director to be necessary for support of the authorized activities of the lessee and otherwise to be consistent with the protection and...

  10. 36 CFR 18.12 - What specific provisions must a lease contain?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... to lessee activities; (h) Appropriate provisions stating that the lessee has no rights of renewal of..., minor additions, buildings and/or structures determined by the Director to be necessary for support of the authorized activities of the lessee and otherwise to be consistent with the protection and...

  11. 36 CFR 18.12 - What specific provisions must a lease contain?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to lessee activities; (h) Appropriate provisions stating that the lessee has no rights of renewal of..., minor additions, buildings and/or structures determined by the Director to be necessary for support of the authorized activities of the lessee and otherwise to be consistent with the protection and...

  12. 36 CFR 18.12 - What specific provisions must a lease contain?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... to lessee activities; (h) Appropriate provisions stating that the lessee has no rights of renewal of..., minor additions, buildings and/or structures determined by the Director to be necessary for support of the authorized activities of the lessee and otherwise to be consistent with the protection and...

  13. Race and Gender Differences in Undergraduate Research Mentoring Structures and Research Outcomes

    ERIC Educational Resources Information Center

    Aikens, Melissa L.; Robertson, Melissa M.; Sadselia, Sona; Watkins, Keiana; Evans, Mara; Runyon, Christopher R.; Eby, Lillian T.; Dolan, Erin L.

    2017-01-01

    Participating in undergraduate research with mentorship from faculty may be particularly important for ensuring the persistence of women and minority students in science. Yet many life science undergraduates at research universities are mentored by graduate or postdoctoral researchers (i.e., postgraduates). We surveyed a national sample of…

  14. Financial Management and Job Social Skills Training Components in a Summer Business Institute

    ERIC Educational Resources Information Center

    Donohue, Brad; Conway, Debbie; Beisecker, Monica; Murphy, Heather; Farley, Alisha; Waite, Melissa; Gugino, Kristin; Knatz, Danielle; Lopez-Frank, Carolina; Burns, Jack; Madison, Suzanne; Shorty, Carrie

    2005-01-01

    Ninety-two adolescents, predominantly ethnic minority high school students, participated in a structured Summer Business Institute (SBI). Participating youth were randomly assigned to receive either job social skills or financial management skills training components. Students who additionally received the job social skills training component were…

  15. Unidimensional Interpretations for Multidimensional Test Items

    ERIC Educational Resources Information Center

    Kahraman, Nilufer

    2013-01-01

    This article considers potential problems that can arise in estimating a unidimensional item response theory (IRT) model when some test items are multidimensional (i.e., show a complex factorial structure). More specifically, this study examines (1) the consequences of model misfit on IRT item parameter estimates due to unintended minor item-level…

  16. Raised incidence rates of all psychoses among migrant groups: findings from the East London first episode psychosis study.

    PubMed

    Coid, Jeremy W; Kirkbride, James B; Barker, Dave; Cowden, Fiona; Stamps, Rebekah; Yang, Min; Jones, Peter B

    2008-11-01

    Certain black and minority ethnic groups are at increased risk for psychoses. It is unknown whether risk for second- and later-generation black and minority ethnic groups in the United Kingdom is universally increased or varies by ethnicity, population structure, or diagnostic category. To examine whether excess risk in black and minority ethnic groups varies by generation status and to determine whether this is explained solely by an excess of broadly defined schizophrenia. Population-based epidemiological survey of first-onset psychoses during a 2-year study period. Three inner-city boroughs in East London, England. Patients Four hundred eighty-four patients with first-episode psychosis aged 18 to 64 years. Nonaffective or affective psychoses according to the DSM-IV. Raised incidence of both nonaffective and affective psychoses were found for all of the black and minority ethnic subgroups compared with white British individuals. The risk of nonaffective psychoses for first and second generations varied by ethnicity (likelihood ratio test, P = .06). Only black Caribbean second-generation individuals were at significantly greater risk compared with their first-generation counterparts (incidence rate ratio, 2.2; 95% confidence interval, 1.1-4.2) [corrected]. No significant differences between first and second generations were observed in other ethnic groups. Asian women but not men of both generations were at increased risk for psychoses compared with white British individuals. Patterns were broadly upheld for the affective psychoses. Both first- and second-generation immigrants were at elevated risk for both nonaffective and affective psychoses, but this varied by ethnicity. Our results suggest that given the same age structure, the risk of psychoses in first and second generations of the same ethnicity will be roughly equal. We suggest that socioenvironmental factors operate differentially by ethnicity but not generation status, even if the exact specification of these stressors differs across generations. Research should focus on differential rates of psychoses by ethnicity rather than between generations.

  17. Differential Deformability of the DNA Minor Groove and Altered BI/BII Backbone Conformational Equilibrium by the Monovalent Ions Li+, Na+, K+ and Rb+ via Water-Mediated Hydrogen Bonding

    PubMed Central

    Savelyev, Alexey; MacKerell, Alexander D.

    2015-01-01

    Recently, we reported the differential impact of the monovalent cations Li+, Na+, K+ and Rb+ on DNA conformational properties. These were identified from variations in the calculated solution-state X-ray DNA spectra as a function of the ion type in the solvation buffer in MD simulations using our recently developed polarizable force field based on the classical Drude oscillator. Changes in the DNA structure were found to mainly involve variations in the minor groove width. Because minor groove dimensions vary significantly in protein-DNA complexes and have been shown to play a critical role in both specific and nonspecific DNA readout, understanding the origins of the observed differential DNA modulation by the first-group monovalent ions is of great biological importance. In the present study we show that the primary microscopic mechanism for the phenomenon is the formation of the water-mediated hydrogen bonds between solvated cations located inside the minor groove and simultaneously to two DNA strands, a process whose intensity and impact on DNA structure depends on both the type of the ion and DNA sequence. Additionally, it is shown that formation of such ion-DNA hydrogen bond complexes appreciably modulates the conformation of the backbone by increasing the population of the BII substate. Notably, the differential impact of the ions on DNA conformational behavior is only predicted by the Drude polarizable model for DNA, with virtually no effect observed from MD simulations utilizing the additive CHARMM36 model. Analysis of dipole moments of the water shows the Drude SWM4 model to possess high sensitivity to changes in the local environment, which indicates the important role of electronic polarization in the salt-dependent conformational properties. This also suggests that inclusion of polarization effects is required to model even relatively simple biological systems such as DNA in various ionic solutions. PMID:26575937

  18. Minor malformations characteristic of the retinoic acid embryopathy and other birth outcomes in children of women exposed to topical tretinoin during early pregnancy.

    PubMed

    Loureiro, Kirsten D; Kao, Kelly K; Jones, Kenneth Lyons; Alvarado, Sonia; Chavez, Carmen; Dick, Lyn; Felix, Robert; Johnson, Diana; Chambers, Christina D

    2005-07-15

    Topical tretinoin (Retin-A) is used to treat acne and photodamaged skin. Its teratogenic potential is of concern due to its similarity to isotretinoin (Accutane), a recognized human teratogen. Through the California Teratogen Information Service and Clinical Research Program, between 1983 and 2003, 106 pregnant women with first-trimester exposure to topical tretinoin were prospectively ascertained and followed. Birth outcomes, including pregnancy loss, major structural defects, and pre- and postnatal growth were compared to 389 similarly and prospectively ascertained women with no topical tretinoin exposure during pregnancy. Because a distinct pattern of malformation had already been described for isotretinoin, we also compared exposed (n = 62) and unexposed (n = 191) infants on the prevalence of a specific subset of minor malformations selected to represent the spectrum of defects comprising the retinoic acid embyopathy. There were no significant differences between groups in the proportion of pregnancies ending in spontaneous abortion (6.6% in exposed vs. 8.5% in unexposed; P = 0.53), or infants with major structural defects (2.2% in exposed vs. 1.2% in unexposed; P = 0.62). In addition, the groups were similar in birth weight, length and head circumference, and there were no significant differences between groups in length of gestation. Furthermore, the prevalence of one or more retinoic acid-specific minor malformations did not differ significantly between groups (12.9% in exposed vs. 9.9% in unexposed; P = 0.51). First-trimester topical tretinoin exposure in this study was not associated with an increased risk of any adverse pregnancy outcome evaluated. Specifically, there was no indication that topical tretinoin is associated with an increased risk for minor malformations that are consistent with the retinoic acid embryopathy. Although it is impossible to exclude the possibility that some women/infants may be uniquely susceptible to topical tretinoin exposure, this study provides further reassurance for women who are inadvertently exposed early in pregnancy. Copyright 2005 Wiley-Liss, Inc.

  19. Structural basis of DNA folding and recognition in an AMP-DNA aptamer complex: distinct architectures but common recognition motifs for DNA and RNA aptamers complexed to AMP.

    PubMed

    Lin, C H; Patel, D J

    1997-11-01

    Structural studies by nuclear magnetic resonance (NMR) of RNA and DNA aptamer complexes identified through in vitro selection and amplification have provided a wealth of information on RNA and DNA tertiary structure and molecular recognition in solution. The RNA and DNA aptamers that target ATP (and AMP) with micromolar affinity exhibit distinct binding site sequences and secondary structures. We report below on the tertiary structure of the AMP-DNA aptamer complex in solution and compare it with the previously reported tertiary structure of the AMP-RNA aptamer complex in solution. The solution structure of the AMP-DNA aptamer complex shows, surprisingly, that two AMP molecules are intercalated at adjacent sites within a rectangular widened minor groove. Complex formation involves adaptive binding where the asymmetric internal bubble of the free DNA aptamer zippers up through formation of a continuous six-base mismatch segment which includes a pair of adjacent three-base platforms. The AMP molecules pair through their Watson-Crick edges with the minor groove edges of guanine residues. These recognition G.A mismatches are flanked by sheared G.A and reversed Hoogsteen G.G mismatch pairs. The AMP-DNA aptamer and AMP-RNA aptamer complexes have distinct tertiary structures and binding stoichiometries. Nevertheless, both complexes have similar structural features and recognition alignments in their binding pockets. Specifically, AMP targets both DNA and RNA aptamers by intercalating between purine bases and through identical G.A mismatch formation. The recognition G.A mismatch stacks with a reversed Hoogsteen G.G mismatch in one direction and with an adenine base in the other direction in both complexes. It is striking that DNA and RNA aptamers selected independently from libraries of 10(14) molecules in each case utilize identical mismatch alignments for molecular recognition with micromolar affinity within binding-site pockets containing common structural elements.

  20. Experimental and computational investigation of supersonic counterflow jet interaction in atmospheric conditions

    NASA Astrophysics Data System (ADS)

    Ivanchenko, Oleksandr

    The flow field generated by the interaction of a converging-diverging nozzle (exit diameter, D=26 mm M=1.5) flow and a choked flow from a minor jet (exit diameter, d=2.6 mm) in a counterflow configuration was investigated. During the tests both the main C-D nozzle and the minor jet stagnation pressures were varied as well as the region of interaction. Investigations were made in the near field, at most about 2D distance, and in the far field, where the repeated patterns of shock waves were eliminated by turbulence. Both nozzles exhausted to the atmospheric pressure conditions. The flow physics was studied using Schlieren imaging techniques, Pitot-tube, conical Mach number probe, Digital Particle Image Velocimetry (DPIV) and acoustic measurement methods. During the experiments in the far field the jets interaction was observed as the minor jet flow penetrates into the main jet flow. The resulting shock structure caused by the minor jet's presence was dependent on the stagnation pressure ratio between the two jets. The penetration length of the minor jet into the main jet was also dependent on the stagnation pressure ratio. In the far field, increasing the minor jet stagnation pressure moved the bow shock forward, towards the main jet exit. In the near field, the minor jet flow penetrates into the main jet flow, and in some cases modified the flow pattern generated by the main jet, revealing a new effect of jet flow interaction that was previously unknown. A correlation function between the flow modes and the jet stagnation pressure ratios was experimentally determined. Additionally the flow interaction between the main and minor jets was simulated numerically using FLUENT. The optimal mesh geometry was found and the k-epsilon turbulence model was defined as the best fit. The results of the experimental and computational studies were used to describe the shock attenuation effect as self-sustain oscillations in supersonic flow. The effects described here can be used in different flow fields to reduce the total pressure losses that occur due to the presence of shock waves. It will result in better designs of ramjet/scramjets combustors, fighter aircraft inlets and as well as in noise reduction of existing aircraft engines. It can also improve performance of rotating machinery; ramjet fuel injectors and aircraft control mechanisms.

  1. Influence of Information and Communication Technologies on the Resilience and Coping of Sexual and Gender Minority Youth in the United States and Canada (Project #Queery): Mixed Methods Survey

    PubMed Central

    McInroy, Lauren B; D'Souza, Sandra A; Austin, Ashley; McCready, Lance T; Eaton, Andrew D; Shade, Leslie R; Wagaman, M Alex

    2017-01-01

    Background Sexual and gender minority youth are a population in peril, exemplified by their disproportionate risk of negative experiences and outcomes. Sexual and gender minority youth may be particularly active users of information and communication technologies (ICTs), and it is important to identify the potential contributions of ICTs to their resilience and well-being. Objective Our aim was to (1) investigate the use of ICTs by sexual and gender minority youth, (2) identify the ways that ICTs influence the resilience and coping of sexual and gender minority youth, focusing on promotion of well-being through self-guided support-seeking (particularly using mobile devices), (3) develop a contextually relevant theoretical conceptualization of resilience incorporating minority stress and ecological approaches, (4) generate best practices and materials that are accessible to multiple interested groups, and (5) identify whether video narratives are a viable alternative to collect qualitative responses in Web-based surveys for youth. Methods Mixed methods, cross-sectional data (N=6309) were collected via a Web-based survey from across the United States and Canada from March-July 2016. The sample was generated using a multipronged, targeted recruitment approach using Web-based strategies and consists of self-identified English-speaking sexual and gender minority youth aged 14-29 with technological literacy sufficient to complete the Web-based survey. The survey was divided into eight sections: (1) essential demographics, (2) ICT usage, (3) health and mental health, (4) coping and resilience, (5) sexual and gender minority youth identities and engagement, (6) fandom communities, (7) nonessential demographics, and (8) a video submission (optional, n=108). The option of a 3-5 minute video submission represents a new research innovation in Web-based survey research. Results Data collection is complete (N=6309), and analyses are ongoing. Proposed analyses include (1) structural equation modeling of quantitative data, (2) grounded theory analysis of qualitative data, and (3) an integrative, mixed methods analysis using a data transformation design. Theoretical and methodological triangulation of analyses integrates an interwoven pattern of results into a comprehensive picture of a phenomenon. Results will be reported in 2017 and 2018. Conclusions This research study will provide critical insights into the emerging use of ICTs by sexual and gender minority youth and identify intervention strategies to improve their well-being and reduce risks encountered by this vulnerable population. Implications for practice, research, and knowledge translation are provided. PMID:28958984

  2. A possible radiation-resistant solar cell geometry using superlattices

    NASA Technical Reports Server (NTRS)

    Goradia, C.; Clark, R.; Brinker, D.

    1985-01-01

    A solar cell structure is proposed which uses a GaAs nipi doping superlattice. An important feature of this structure is that photogenerated minority carriers are very quickly collected in a time shorter than bulk lifetime in the fairly heavily doped n and p layers and these carriers are then transported parallel to the superlattice layers to selective ohmic contacts. Assuming that these already-separated carriers have very long recombination lifetimes, due to their across an indirect bandgap in real space, it is argued that the proposed structure may exhibit superior radiation tolerance along with reasonably high beginning-of-life efficiency.

  3. Semiclassical Origin of Superdeformed Shell Structure in the Spheroidal Cavity Model

    NASA Astrophysics Data System (ADS)

    Arita, K.; Sugita, A.; Matsuyanagi, K.

    1998-12-01

    Classical periodic orbits responsible for emergence of the superdeformed shell structures of single-particle motion in spheroidal cavities are identified and their relative contributions to the shell structures are evaluated. Both prolate and oblate superdeformations (axis ratio approximately 2:1) as well as prolate hyperdeformation (axis ratio approximately 3:1) are investigated. Fourier transforms of quantum spectra clearly show that three-dimensional periodic orbits born out of bifurcations of planar orbits in the equatorial plane become predominant at large prolate deformations, while butterfly-shaped planar orbits bifurcated from linear orbits along the minor axis are important at large oblate deformations.

  4. Systematic mapping review of the factors influencing physical activity and sedentary behaviour in ethnic minority groups in Europe: a DEDIPAC study.

    PubMed

    Langøien, Lars Jørun; Terragni, Laura; Rugseth, Gro; Nicolaou, Mary; Holdsworth, Michelle; Stronks, Karien; Lien, Nanna; Roos, Gun

    2017-07-24

    Physical activity and sedentary behaviour are associated with health and wellbeing. Studies indicate that ethnic minority groups are both less active and more sedentary than the majority population and that factors influencing these behaviours may differ. Mapping the factors influencing physical activity and sedentary behaviour among ethnic minority groups living in Europe can help to identify determinants of physical activity and sedentary behaviour, research gaps and guide future research. A systematic mapping review was conducted to map the factors associated with physical activity and sedentary behaviour among ethnic minority groups living in Europe (protocol PROSPERO ID = CRD42014014575). Six databases were searched for quantitative and qualitative research published between 1999 and 2014. In synthesizing the findings, all factors were sorted and structured into clusters following a data driven approach and concept mapping. Sixty-three articles were identified out of 7794 returned by the systematic search. These included 41 quantitative and 22 qualitative studies. Of these 58 focused on physical activity, 5 on both physical activity and sedentary behaviour and none focused on sedentary behaviour. The factors associated with physical activity and sedentary behaviour were grouped into eight clusters. Social & cultural environment (n = 55) and Psychosocial (39) were the clusters containing most factors, followed by Physical environment & accessibility (33), Migration context (15), Institutional environment (14), Social & material resources (12), Health and health communication (12), Political environment (3). An important finding was that cultural and religious issues, in particular those related to gender issues, were recurring factors across the clusters. Physical activity and sedentary behaviour among ethnic minority groups living in Europe are influenced by a wide variety of factors, especially informed by qualitative studies. More comparative studies are needed as well as inclusion of a wider spectrum of the diverse ethnic minority groups resettled in different European countries. Few studies have investigated factors influencing sedentary behaviour. It is important in the future to address specific factors influencing physical activity and sedentary behaviour among different ethnic minority groups in order to plan and implement effective interventions.

  5. Facilitating the recruitment of minority ethnic people into research: qualitative case study of South Asians and asthma.

    PubMed

    Sheikh, Aziz; Halani, Laila; Bhopal, Raj; Netuveli, Gopalakrishnan; Partridge, Martyn R; Car, Josip; Griffiths, Chris; Levy, Mark

    2009-10-01

    There is international interest in enhancing recruitment of minority ethnic people into research, particularly in disease areas with substantial ethnic inequalities. A recent systematic review and meta-analysis found that UK South Asians are at three times increased risk of hospitalisation for asthma when compared to white Europeans. US asthma trials are far more likely to report enrolling minority ethnic people into studies than those conducted in Europe. We investigated approaches to bolster recruitment of South Asians into UK asthma studies through qualitative research with US and UK researchers, and UK community leaders. Interviews were conducted with 36 researchers (19 UK and 17 US) from diverse disciplinary backgrounds and ten community leaders from a range of ethnic, religious, and linguistic backgrounds, followed by self-completion questionnaires. Interviews were digitally recorded, translated where necessary, and transcribed. The Framework approach was used for analysis. Barriers to ethnic minority participation revolved around five key themes: (i) researchers' own attitudes, which ranged from empathy to antipathy to (in a minority of cases) misgivings about the scientific importance of the question under study; (ii) stereotypes and prejudices about the difficulties in engaging with minority ethnic populations; (iii) the logistical challenges posed by language, cultural differences, and research costs set against the need to demonstrate value for money; (iv) the unique contexts of the two countries; and (v) poorly developed understanding amongst some minority ethnic leaders of what research entails and aims to achieve. US researchers were considerably more positive than their UK counterparts about the importance and logistics of including ethnic minorities, which appeared to a large extent to reflect the longer-term impact of the National Institutes of Health's requirement to include minority ethnic people. Most researchers and community leaders view the broadening of participation in research as important and are reasonably optimistic about the feasibility of recruiting South Asians into asthma studies provided that the barriers can be overcome. Suggested strategies for improving recruitment in the UK included a considerably improved support structure to provide academics with essential contextual information (e.g., languages of particular importance and contact with local gatekeepers), and the need to ensure that care is taken to engage with the minority ethnic communities in ways that are both culturally appropriate and sustainable; ensuring reciprocal benefits was seen as one key way of avoiding gatekeeper fatigue. Although voluntary measures to encourage researchers may have some impact, greater impact might be achieved if UK funding bodies followed the lead of the US National Institutes of Health requiring recruitment of ethnic minorities. Such a move is, however, likely in the short- to medium-term, to prove unpopular with many UK academics because of the added "hassle" factor in engaging with more diverse populations than many have hitherto been accustomed to.

  6. Facilitating the Recruitment of Minority Ethnic People into Research: Qualitative Case Study of South Asians and Asthma

    PubMed Central

    Sheikh, Aziz; Halani, Laila; Bhopal, Raj; Netuveli, Gopalakrishnan; Partridge, Martyn R.; Car, Josip; Griffiths, Chris; Levy, Mark

    2009-01-01

    Background There is international interest in enhancing recruitment of minority ethnic people into research, particularly in disease areas with substantial ethnic inequalities. A recent systematic review and meta-analysis found that UK South Asians are at three times increased risk of hospitalisation for asthma when compared to white Europeans. US asthma trials are far more likely to report enrolling minority ethnic people into studies than those conducted in Europe. We investigated approaches to bolster recruitment of South Asians into UK asthma studies through qualitative research with US and UK researchers, and UK community leaders. Methods and Findings Interviews were conducted with 36 researchers (19 UK and 17 US) from diverse disciplinary backgrounds and ten community leaders from a range of ethnic, religious, and linguistic backgrounds, followed by self-completion questionnaires. Interviews were digitally recorded, translated where necessary, and transcribed. The Framework approach was used for analysis. Barriers to ethnic minority participation revolved around five key themes: (i) researchers' own attitudes, which ranged from empathy to antipathy to (in a minority of cases) misgivings about the scientific importance of the question under study; (ii) stereotypes and prejudices about the difficulties in engaging with minority ethnic populations; (iii) the logistical challenges posed by language, cultural differences, and research costs set against the need to demonstrate value for money; (iv) the unique contexts of the two countries; and (v) poorly developed understanding amongst some minority ethnic leaders of what research entails and aims to achieve. US researchers were considerably more positive than their UK counterparts about the importance and logistics of including ethnic minorities, which appeared to a large extent to reflect the longer-term impact of the National Institutes of Health's requirement to include minority ethnic people. Conclusions Most researchers and community leaders view the broadening of participation in research as important and are reasonably optimistic about the feasibility of recruiting South Asians into asthma studies provided that the barriers can be overcome. Suggested strategies for improving recruitment in the UK included a considerably improved support structure to provide academics with essential contextual information (e.g., languages of particular importance and contact with local gatekeepers), and the need to ensure that care is taken to engage with the minority ethnic communities in ways that are both culturally appropriate and sustainable; ensuring reciprocal benefits was seen as one key way of avoiding gatekeeper fatigue. Although voluntary measures to encourage researchers may have some impact, greater impact might be achieved if UK funding bodies followed the lead of the US National Institutes of Health requiring recruitment of ethnic minorities. Such a move is, however, likely in the short- to medium-term, to prove unpopular with many UK academics because of the added “hassle” factor in engaging with more diverse populations than many have hitherto been accustomed to. Please see later in the article for the Editors' Summary PMID:19823568

  7. Distant neighbor base sequence context effects in human nucleotide excision repair of a benzo[a]pyrene-derived DNA lesion

    PubMed Central

    Cai, Yuqin; Kropachev, Konstantin; Xu, Rong; Tang, Yijin; Kolbanovskii, Marina; Kolbanovskii, Alexander; Amin, Shantu; Patel, Dinshaw J.; Broyde, Suse; Geacintov, Nicholas E.

    2010-01-01

    Summary The effects of non-nearest base sequences, beyond the nucleotides flanking a DNA lesion on either side, on nucleotide excision repair (NER) in extracts from human cells were investigated. We constructed two duplexes containing the same minor groove-aligned 10S (+)-trans-anti-B[a]P-N2-dG (G*) DNA adduct, derived from the environmental carcinogen benzo[a]pyrene (B[a]P): 5′-C-C-A-T-C-G*-C-T-A-C-C-3′ (CG*C-I), and 5′-C-A-C3-A4-C5-G*-C-A-C-A-C-3′ (CG*C-II). We utilized gel electrophoresis to compare the extent of DNA bending, and molecular dynamics (MD) simulations to analyze the structural characteristics of these two DNA duplexes. The NER efficiencies are 1.6 ± 0.2 times greater in the case of the CG*C-II than the CG*C-I sequence context in 135-mer duplexes. Gel electrophoresis and self-ligation circularization experiments revealed that the CG*C-II duplex is more bent than the CG*C-I duplex, while MD simulations showed that the unique -C3-A4-C5- segment in the CG*C-II duplex plays a key role. The presence of a minor groove-positioned guanine amino group, namely, the Watson-Crick partner to C3, acts as a wedge; facilitated by a highly deformable local -C3-A4- base step, this amino group allows the B[a]P ring system to produce a more enlarged minor groove in CG*C-II than in CG*C-I, as well as a local untwisting and enlarged and flexible Roll only in the CG*C-II sequence. These structural properties fit well with our prior findings that in the case of the family of minor groove 10S (+)-trans-anti-B[a]P-N2-dG lesions, flexible bends and enlarged minor groove widths (Cai et al. (2009) J. Mol. Biol., 385: 30–44) constitute NER recognition signals, and extend our understanding of sequence context effects on NER to the neighbors that are distant to the lesion. PMID:20399214

  8. Method of producing buried porous silicon-geramanium layers in monocrystalline silicon lattices

    NASA Technical Reports Server (NTRS)

    Fathauer, Robert W. (Inventor); George, Thomas (Inventor); Jones, Eric W. (Inventor)

    1997-01-01

    Lattices of alternating layers of monocrystalline silicon and porous silicon-germanium have been produced. These single crystal lattices have been fabricated by epitaxial growth of Si and Si--Ge layers followed by patterning into mesa structures. The mesa structures are stain etched resulting in porosification of the Si--Ge layers with a minor amount of porosification of the monocrystalline Si layers. Thicker Si--Ge layers produced in a similar manner emitted visible light at room temperature.

  9. Ethnic health care advisors: a good strategy to improve the access to health care and social welfare services for ethnic minorities?

    PubMed

    Hesselink, Arlette E; Verhoeff, Arnoud P; Stronks, Karien

    2009-10-01

    Empirical studies indicate that ethnic minorities have limited access to health care and welfare services compared with the host population. To improve this access, ethnic health care (HC) advisors were introduced in four districts in Amsterdam, the Netherlands. HC advisors work for all health care and welfare services and their main task is to provide information on health care and welfare to individuals and groups and refer individuals to services. Action research was carried out over a period of 2 years to find out whether and how this function can contribute to improve access to services for ethnic minorities. Information was gathered by semi-structured interviews, analysing registration forms and reports, and attending meetings. The function's implementation and characteristics differed per district. The ethnicity of the health care advisors corresponded to the main ethnic groups in the district: Moroccan and Turkish (three districts) and sub-Sahara African and Surinamese (one district). HC advisors reached many ethnic inhabitants (n = 2,224) through individual contacts. Half of them were referred to health care and welfare services. In total, 576 group classes were given. These were mostly attended by Moroccan and Turkish females. Outreach activities and office hours at popular locations appeared to be important characteristics for actually reaching ethnic minorities. Furthermore, direct contact with a well-organized back office seems to be important. HC advisors were able to reach many ethnic minorities, provide information about the health care and welfare system, and refer them to services. Besides adapting the function to the local situation, some general aspects for success can be indicated: the ethnic background of the HC advisor should correspond to the main ethnic minority groups in the district, HC advisors need to conduct outreach work, there must be a well-organized back office to refer clients to, and there needs to be enough commitment among professionals of local health and welfare services.

  10. Diversity in the US Infectious Diseases Workforce: Challenges for Women and Underrepresented Minorities.

    PubMed

    Aberg, Judith A; Blankson, Joel; Marrazzo, Jeanne; Adimora, Adaora A

    2017-09-15

    Research documents significant gender-based salary inequities among physicians and ongoing inadequacies in recruitment and promotion of physicians from underrepresented minority groups. Given the complexity of the social forces that promote these disparities, their elimination will likely require quantitative and qualitative research to understand the pathways that lead to them and to develop effective solutions. Interventions to combat implicit bias will be required, and structural interventions that hold medical school leadership accountable are needed to achieve and maintain salary equity and racial and gender diversity at all levels. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  11. Effects of Minor Alloying Additions on the Microstructure, Toughness, and Creep Strength of Directionally Solidified NiAl-31Cr-3Mo

    NASA Technical Reports Server (NTRS)

    Whittenberger, J. D.; Raj, S. V.; Locci, I. E.; Salem, J. A.

    2001-01-01

    A study of the effects of small (0.25 to 1.0 at%) fifth element additions to the structure and mechanical properties of directionally solidified (DS) NiAl-31Cr-3Mo has been undertaken. Essentially all the additions changed the as-DS'ed microstructure from lamellar eutectic grains to cells and, in some cases, introduced NiAl dendrites and/or third phases. In general the alloying additions did not improve strength or toughness over that possessed by the base composition; only Hf and, perhaps Ti, gave a minor increase in elevated temperature creep resistance. The lack of improvement in creep properties is probably due to inability to precipitation harden NiAl.

  12. Improved half-metallic gap of zincblende half-metal superlattices with the Tran-Blaha modified Becke-Johnson density functional

    NASA Astrophysics Data System (ADS)

    Guo, San-Dong

    2016-08-01

    Binary transition-metal pnictides and chalcogenides half-metallic ferromagnetic materials with zincblende structure, being compatible with current semiconductor technology, can be used to make high-performance spintronic devices. Here, we investigate electronic structures and magnetic properties of composite structure ((CrX)2 /(YX)2 (X=As, Sb; Se, Te and Y=Ga; Zn) superlattices) of zincblende half-metallic ferromagnetism and semiconductor by using Tran and Blaha's modified Becke and Johnson (mBJ) exchange potential. Calculated results show that they all are half-metallic ferromagnets with both generalized gradient approximation (GGA) and mBJ, and the total magnetic moment per formula unit follows a Slater-Pauling-like "rule of 8". The key half-metallic gaps by using mBJ are enhanced with respect to GGA results, which is because mBJ makes the occupied minority-spin p-bands move toward lower energy, but toward higher energy for empty minority-spin Cr-d bands. When the spin-orbit coupling (SOC) is included, the spin polarization deviates from 100%, and a most reduced polarization of 98.3% for (CrSb)2 /(GaSb)2, which indicates that SOC has small effects, of the order of 1%, in the considered four kinds of superlattice.

  13. Theoretical investigation of the SAW properties of ferroelectric film composite structures.

    PubMed

    Shih, W C; Wu, M S

    1998-01-01

    The characteristics of surface acoustic waves (SAW) propagating on a three-layered structure consisting of a perovskite-type ferroelectric film, a buffer layer and a semiconductor substrate have been studied theoretically. Large coupling coefficients (K(2)) can be obtained when the interdigital transducer (IDT) is on top of the perovskite-type ferroelectric film, with (type 4) and without (type 3) the floating-plane electrode at the perovskite-type ferroelectric film-buffer layer interface. In the above cases, the peak values of K (2) Of the Pb(Zr,Ti)O(3) (PZT) films (3.2%-3.8%) are higher than those of the BaTiO(3) (BT) and PbTiO(3) (PT) films. In the IDT configuration of type 4, there exists a minor peak of the coupling coefficients for the PZT and BT films, but not for the PT films when the normalized thickness (hK) of the perovskite-type ferroelectric film is about 0.3. The minor peak values of the coupling coefficients (0.62%-0.93%) for different layered structures (PZT/STO/Si, PZT/MgO/Si, and PZT/MgO/GaAs) all decrease when we increase hK value from 0 to 0.25. The results could be useful in the integration of ferroelectric devices, semiconductor devices, and SAW devices on the same substrate.

  14. A multigroup confirmatory factor analysis of the Patient Health Questionnaire-9 among English- and Spanish-speaking Latinas.

    PubMed

    Merz, Erin L; Malcarne, Vanessa L; Roesch, Scott C; Riley, Natasha; Sadler, Georgia Robins

    2011-07-01

    Depression is a significant problem for ethnic minorities that remains understudied partly due to a lack of strong measures with established psychometric properties. One screening tool, the Patient Health Questionnaire-9 (PHQ-9), which was developed for use in primary care has also gained popularity in research settings. The reliability and validity of the PHQ-9 has been well established among predominantly Caucasian samples, in addition to many minority groups. However, there is little evidence regarding its utility among Hispanic Americans, a large and growing cultural group in the United States. In this study, we investigated the reliability and structural validity of the PHQ-9 in Hispanic American women. A community sample of 479 Latina women from southern California completed the PHQ-9 in their preferred language of English or Spanish. Cronbach's alphas suggested that there was good internal consistency for both the English- and Spanish-language versions. Structural validity was investigated using multigroup confirmatory factor analysis. Results support a similar one-factor structure with equivalent response patterns and variances among English- and Spanish-speaking Latinas. These results suggest that the PHQ-9 can be used with confidence in both English and Spanish versions to screen Latinas for depression.

  15. A Multigroup Confirmatory Factor Analysis of the Patient Health Questionnaire-9 among English- and Spanish-speaking Latinas

    PubMed Central

    Merz, Erin L.; Malcarne, Vanessa L.; Roesch, Scott C.; Riley, Natasha; Sadler, Georgia Robins

    2014-01-01

    Depression is a significant problem for ethnic minorities that remains understudied partly due to a lack of strong measures with established psychometric properties. One screening tool, the Patient Health Questionnaire-9 (PHQ-9), which was developed for use in primary care has also gained popularity in research settings. The reliability and validity of the PHQ-9 has been well established among predominantly Caucasian samples, in addition to many minority groups. However, there is little evidence regarding its utility among Hispanic Americans, a large and growing cultural group in the United States. In this study, we investigated the reliability and structural validity of the PHQ-9 in Hispanic American women. A community sample of 479 Latina women from southern California completed the PHQ-9 in their preferred language of English or Spanish. Cronbach’s alphas suggested that there was good internal consistency for both the English- and Spanish-language versions. Structural validity was investigated using multigroup confirmatory factor analysis (CFA). Results support a similar one-factor structure with equivalent response patterns and variances among English- and Spanish-speaking Latinas. These results suggest that the PHQ-9 can be used with confidence in both English and Spanish versions to screen Latinas for depression. PMID:21787063

  16. [Visible minority nurses and vertical mobility in hospitals

    PubMed

    Bouabdillah, Naima; Holmes, Dave; Tourigny, Jocelyne

    2016-12-01

    Canada has experienced a significant change in its ethnic and cultural composition in recent decades. The sustained immigration from non-European countries has given rise to new generation of visible minorities. This new trend is clearly reflected in healthcare institutions. However, the number of visible minority nurses (VMN) is particularly low in management positions. This research adopting critical ethnography and postcolonial approach focuses on the career paths of VMN in Canadian healthcare institutions. Nurses (n = eight, MVN) and managers (n = four caucasian) participated in a series of semi-structured interviews to gather relevant information about the representativeness of the VMN in management positions. Theoretical framework « Othering » was used to guide this research as it makes the link with “la lutte de classement” of Bourdieu. Four main themes closely associated with barriers emerged from the analysis namely ; Hiring and Promotion ; instrumentalization of IMV ; interpersonal and suffering and defensive strategies. Results showed that the VMN faced obstacles, often invisible, that contribute to keeping them at a lower level of the institutional hierarchy, including the hiring and promotion process that they describe as unfair and discriminatory.

  17. Assignment of selected hyperfine proton NMR resonances in the met forms of Glycera dibranchiata monomer hemoglobins and comparisons with sperm whale metmyoglobin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Constantinidis, I.; Satterlee, J.D.; Pandey, R.K.

    1988-04-19

    This work indicates a high degree of purity for our preparations of all three of the primary Glycera dibranchiata monomer hemoglobins and details assignments of the heme methyl and vinyl protons in the hyperfine shift region of the ferric (aquo.) protein forms. The assignments were carried out by reconstituting the apoproteins of each component with selectively deuteriated hemes. The results indicate that even though the individual component preparations consist of essentially a single protein, the proton NMR spectra indicate spectroscopic heterogeneity. Evidence is presented for identification and classification of major and minor protein forms that are present in solutions ofmore » each component. Finally, in contrast to previous results, a detailed analysis of the proton hyperfine shift patterns of the major and minor forms of each component, in comparison to the major and minor forms of metmyoglobin, leads to the conclusions that the corresponding forms of the proteins from each species have strikingly similar heme-globin contacts and display nearly identical heme electronic structures and coordination numbers.« less

  18. Sequence-specific binding of counterions to B-DNA

    PubMed Central

    Denisov, Vladimir P.; Halle, Bertil

    2000-01-01

    Recent studies by x-ray crystallography, NMR, and molecular simulations have suggested that monovalent counterions can penetrate deeply into the minor groove of B form DNA. Such groove-bound ions potentially could play an important role in AT-tract bending and groove narrowing, thereby modulating DNA function in vivo. To address this issue, we report here 23Na magnetic relaxation dispersion measurements on oligonucleotides, including difference experiments with the groove-binding drug netropsin. The exquisite sensitivity of this method to ions in long-lived and intimate association with DNA allows us to detect sequence-specific sodium ion binding in the minor groove AT tract of three B-DNA dodecamers. The sodium ion occupancy is only a few percent, however, and therefore is not likely to contribute importantly to the ensemble of B-DNA structures. We also report results of ion competition experiments, indicating that potassium, rubidium, and cesium ions bind to the minor groove with similarly weak affinity as sodium ions, whereas ammonium ion binding is somewhat stronger. The present findings are discussed in the light of previous NMR and diffraction studies of sequence-specific counterion binding to DNA. PMID:10639130

  19. Self-care and depression in patients with chronic heart failure.

    PubMed

    Holzapfel, Nicole; Löwe, Bernd; Wild, Beate; Schellberg, Dieter; Zugck, Christian; Remppis, Andrew; Katus, Hugo A; Haass, Markus; Rauch, Bernhard; Jünger, Jana; Herzog, Wolfgang; Müller-Tasch, Thomas

    2009-01-01

    Although chronic heart failure (CHF) is often complicated by comorbid depression and poor self-care, little is known about their specific association in patients with CHF. To investigate self-care behavior among patients with CHF with different degrees of depression severity. A total of 287 patients with documented CHF, New York Heart Association functional class II to IV, completed the European Heart Failure Self-Care Behavior Scale. The Structured Clinical Interview for DSM (SCID) IV served as the criterion standard for the presence of a depressive disorder. Analyses of covariance and linear regression analyses revealed that patients with CHF with minor depression reported significantly lower levels of self-care than patients with major depression (P = .003) and nondepressed patients (P = .014). In addition to minor depression, age (P < or = .001), multimorbidity (P = .01), left ventricular ejection fraction (P = .001), and family status (P = .01) were determinants of self-care. Our results demonstrate that patients with CHF with minor depression and not major depression are at higher risk for poor self-care and its resulting consequences, such as symptom deterioration and frequent hospitalization.

  20. Primary care: choices and opportunities for racial/ethnic minority populations in the USA and UK--a comparative analysis.

    PubMed

    Smith, M B

    1999-08-01

    This paper examines and compares the choices made and the opportunities provided by the United States and the United Kingdom in delivering primary care services to their racial/ethnic minority populations. While both nations agree that the most effective strategy for health service delivery to a diverse population lies in primary care, their approaches to obtaining this goal have been quite different. Sociological theories of functionalism and conflict perspective provide the analytical and organizing framework of the paper. Within this theoretical context, the health systems in place in each country are examined as an outgrowth of the larger socio-political, economic and cultural structures of the US and UK. Analysis of the advance of managed care in the US and the recent NHS reforms are also discussed in terms of lessons learned and the difficulties that lay ahead in order to ensure that these new developments contribute significantly to eliminating the disproportionately worse health status of racial ethnic minorities. Towards that goal the paper identifies opportunities for collaboration and specific recommendations for future action by both countries.

  1. Electronic structure and properties of lanthanum

    NASA Astrophysics Data System (ADS)

    Nixon, Lane; Papaconstantopoulos, Dimitrios

    2008-03-01

    The total energy and electronic structure of lanthanum have been calculated in the bcc, fcc, hcp and dhcp structures for pressures up to 50 GPa. The full potential linearized-augmented-planewave method was used with both the local-density and general-gradient approximations. The correct phase ordering has been found, with lattice parameters and bulk moduli in good agreement with experimental data. The GGA method shows excellent agreement overall while the LDA results show larger discrepancies. The calculated strain energies for the fcc and bcc structures demonstrate the respective stable and unstable configurations at ambient conditions. The calculated superconductivity properties under pressure for the fcc structure are also found to agree well with measurements. Both LDA and GGA, with minor differences, reproduce well the experimental results for Tc.

  2. Structure of a zinc oxide ultra-thin film on Rh(100)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yuhara, J.; Kato, D.; Matsui, T.

    The structural parameters of ultra-thin zinc oxide films on Rh(100) are investigated using low-energy electron diffraction intensity (LEED I–V) curves, scanning tunneling microscopy (STM), and first-principles density functional theory (DFT) calculations. From the analysis of LEED I–V curves and DFT calculations, two optimized models A and B are determined. Their structures are basically similar to the planer h-BN ZnO(0001) structure, although some oxygen atoms protrude from the surface, associated with an in-plane shift of Zn atoms. From a comparison of experimental STM images and simulated STM images, majority and minority structures observed in the STM images represent the two optimizedmore » models A and B, respectively.« less

  3. Minority undergraduate programs intended to increase participation in biomedical careers.

    PubMed

    MacLachlan, Anne J

    2012-01-01

    This article reviews a selection of undergraduate programs intended to increase successful minority participation in science, technology, engineering, and mathematics majors, potentially leading to biomedical careers. The object is to examine their structure, consider how well they address the issues of the target population, and assess the extent to which they have met/meet their goals. As a means of conducting this review, the first step is to examine the concepts used as the building blocks for program design. These concepts are found in a shared, yet often undefined, vocabulary used in most undergraduate programs for minority students. The hypothesis is that a shared vocabulary obscures a broad range of meaning and interpretation that has serious ramifications affecting student success. How these building blocks are understood and implemented strongly reflects the institution where the program is housed. The discussion further considers the nature of a number of programs created by the National Science Foundation and the National Institutes of Health specifically for underrepresented minority students and examines one program in detail, the University of California Berkeley's National Science Foundation Research Experience for Undergraduates Program in Molecular, Cell, and Evolutionary Biology. The characteristics of federally organized programs and the Research Experience for Undergraduates are contrasted with 2 very successful student-centered local programs based on a different conceptual model. © 2012 Mount Sinai School of Medicine.

  4. “We’re All in This Together”: A Qualitative Study of Predominantly Low Income Minority Participants in a Yoga Trial for Chronic Low Back Pain

    PubMed Central

    Keosaian, Julia E.; Lemaster, Chelsey M.; Dresner, Danielle; Godersky, Margo E.; Paris, Ruth; Sherman, Karen J.; Saper, Robert B.

    2016-01-01

    Objective To explore the experiences of low-income minority adults taking part in a yoga dosing trial for chronic low back pain. Design Individual semi-structured interviews were conducted with nineteen participants recruited from a randomized yoga dosing trial for predominantly low-income minority adults with chronic low back pain. Interviews discussed the impact of yoga on low back pain and emotions; other perceived advantages or disadvantages of the intervention; and facilitators and barriers to practicing yoga. Interviews were audio taped and transcribed, coded using ATLAS.ti software, and analyzed with inductive and deductive thematic analysis methods. Setting Boston Medical Center, Boston, MA, USA Results Participants viewed yoga as a means of pain relief and attributed improved mood, greater ability to manage stress, and enhanced relaxation to yoga. Overall, participants felt empowered to self-manage their pain. Some found yoga to be helpful in being mindful of their emotions and accepting of their pain. Trust in the yoga instructors was a commonly cited facilitator for yoga class attendance. Lack of time, motivation, and fear of injury were reported barriers to yoga practice. Conclusions Yoga is a multidimensional treatment for low back pain that has the potential to favorably impact health in a predominantly low-income minority population. PMID:26860799

  5. Partner Preference Among Men Who Have Sex with Men: Potential Contribution to Spread of HIV Within Minority Populations.

    PubMed

    Phillips, Gregory; Birkett, Michelle; Hammond, Sydney; Mustanski, Brian

    2016-06-01

    Human immunodeficiency virus (HIV) disproportionately affects men who have sex with men (MSM) in the United States. Most prior research into drivers of HIV transmission has focused on individual characteristics rather than on dyadic-level behaviors such as sex partner selection. This article explores racial/ethnic preferences in sex and relationship partner selection among MSM to further contextualize the spread of HIV within minority groups. Participants were recruited through a mobile application (app) for men to meet other men in 2015 and completed an online survey on behaviors related to HIV risk. All analyses on the sample of 530 MSM were conducted in 2015. There was significant homophily in partner selection within racial/ethnic minorities, but not for white MSM. In general, mobile app-using MSM reported a general preference for white and Hispanic men and a dispreference for black and Asian men, both for sex and relationship partners. Racial/ethnic preferences were found to drive intentions to form partnerships within this sample. Combined with the stigma many of these racial/ethnic minorities may also feel from homophobic attitudes within their own racial/ethnic communities, these MSM may be at particular risk for social isolation. These partner preferences likely affect the structure of the sexual networks of MSM and may contribute to increased clustering within high HIV incident sexual networks.

  6. Partner Preference Among Men Who Have Sex with Men: Potential Contribution to Spread of HIV Within Minority Populations

    PubMed Central

    Birkett, Michelle; Hammond, Sydney; Mustanski, Brian

    2016-01-01

    Abstract Purpose: Human immunodeficiency virus (HIV) disproportionately affects men who have sex with men (MSM) in the United States. Most prior research into drivers of HIV transmission has focused on individual characteristics rather than on dyadic-level behaviors such as sex partner selection. This article explores racial/ethnic preferences in sex and relationship partner selection among MSM to further contextualize the spread of HIV within minority groups. Methods: Participants were recruited through a mobile application (app) for men to meet other men in 2015 and completed an online survey on behaviors related to HIV risk. All analyses on the sample of 530 MSM were conducted in 2015. Results: There was significant homophily in partner selection within racial/ethnic minorities, but not for white MSM. In general, mobile app-using MSM reported a general preference for white and Hispanic men and a dispreference for black and Asian men, both for sex and relationship partners. Conclusion: Racial/ethnic preferences were found to drive intentions to form partnerships within this sample. Combined with the stigma many of these racial/ethnic minorities may also feel from homophobic attitudes within their own racial/ethnic communities, these MSM may be at particular risk for social isolation. These partner preferences likely affect the structure of the sexual networks of MSM and may contribute to increased clustering within high HIV incident sexual networks. PMID:26907954

  7. [The concept mapping of representations of the future of health services in French in linguistic minority].

    PubMed

    Bouchard, Louise

    2013-06-06

    In the context of institutional incompleteness affecting the official minority language communities, we examine how the Francophones in a minority context see the future of health services offered in French. The study is based on a participatory methodology: the concept mapping will serve to identify the conceptual universe of a given problem. From a master statement such as: "When I think about the future of health services in French, I think of ...", participants are invited to make as many statements as come to mind. These statements are then categorized individually and treated collectively through a multivariate analysis. The main themes emerging from the mapping exercise indicate the issues and challenges raised by the participants, namely the geographical context, specific needs, language rights, education and training, human resources, bilingualism and translation, the minority experience, active offer, the role of governmental bodies, community mobilization, collaboration and networking. The participatory approach that concept mapping allows is interesting in more than one way: its flexibility provides a space for both individual and collective reflection; it allows identification and structuring of the crucial dimensions of an issue; and the research outcomes are useful both to researchers and participants in guiding action and achieving goals. Social actors can therefore benefit from a collective dynamic to reflect on the foundations for the development and organization of health services in French.

  8. The Role of Minority Stressors in Lesbian Relationship Commitment and Persistence over Time.

    PubMed

    Barrantes, Renzo J; Eaton, Asia A; Veldhuis, Cindy B; Hughes, Tonda L

    2017-06-01

    The Investment Model of relationship commitment uses interpersonal investment, relationship satisfaction, quality of alternatives, and commitment to predict relationship longevity (Rusbult, 1980, 1983). Although ample support for the Investment Model has been found in heterosexual couples, it appears to be less powerful in predicting stability in same-sex relationships (Beals, Impett, & Peplau, 2002), potentially because the model does not account for factors unique to same-sex relationships, such as anti-gay discrimination. However, no research has tested the nature and power of sexual minority stress factors in predicting same-sex relationship stability over time. Using secondary, longitudinal data collected from a diverse sample of lesbian women in relationships ( N = 211), we examined how internalized homonegativity, sexual identity disclosure, and workplace discrimination affected the Investment Model antecedents of relationship persistence: satisfaction, quality of alternatives, and investment. We tested the influence of sexual minority stressors on Investment Model processes using structural equations modeling and found that sexual identity disclosure was positively associated with satisfaction and investment, internalized homonegativity was only negatively associated with satisfaction and investment, while workplace discrimination was negatively associated with alternatives. Moreover, both relationship satisfaction and investment influenced commitment which predicted persistence in these relationships over about seven years' time, demonstrating support for the Investment Model. Our findings support the addition of sexual minority stress variables to the Investment Model when examining same-sex relationships and implications are discussed.

  9. Mind the gap: predicting the positive mental health of adult sexual minority Canadians.

    PubMed

    Peter, Tracey

    2017-03-21

    The goal of the study is to investigate possible predictors of positive mental health, and whether they differ across sexual identity adult groups. Using data from the 2012 Canadian Community Health Survey on Mental Health, multivariate analyses were conducted, including interaction terms, to assess the effects of sexual orientation on various mental illness, health-risk behaviors, and sociological indicators and their correlations with positive mental health. Substantial effect sizes were observed across all sexual identity groups for psychological distress, social provisions and sense of belonging in terms of their influence on positive mental health. However, various mental health disorders, suicidality, and whether or not care needs were being met varied considerably in the disaggregated analysis, suggesting that there are key differences among sexual minority groups when it comes to predicting positive mental health. This study represents perhaps the largest population-based analysis of positive mental health, which is both theoretically informed and psychometrically verified, on sexual minority adults. Findings raise important concerns regarding the lower than average levels of positive mental health for all sexual minorities, which may be explained, at least in part, to the health care system's tendency to focus primarily on individual treatment needs rather than broader socio-structural aspects within a mental health promotion framework. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. The Role of Minority Stressors in Lesbian Relationship Commitment and Persistence over Time

    PubMed Central

    Barrantes, Renzo J.; Eaton, Asia A.; Veldhuis, Cindy B.; Hughes, Tonda L.

    2017-01-01

    The Investment Model of relationship commitment uses interpersonal investment, relationship satisfaction, quality of alternatives, and commitment to predict relationship longevity (Rusbult, 1980, 1983). Although ample support for the Investment Model has been found in heterosexual couples, it appears to be less powerful in predicting stability in same-sex relationships (Beals, Impett, & Peplau, 2002), potentially because the model does not account for factors unique to same-sex relationships, such as anti-gay discrimination. However, no research has tested the nature and power of sexual minority stress factors in predicting same-sex relationship stability over time. Using secondary, longitudinal data collected from a diverse sample of lesbian women in relationships (N = 211), we examined how internalized homonegativity, sexual identity disclosure, and workplace discrimination affected the Investment Model antecedents of relationship persistence: satisfaction, quality of alternatives, and investment. We tested the influence of sexual minority stressors on Investment Model processes using structural equations modeling and found that sexual identity disclosure was positively associated with satisfaction and investment, internalized homonegativity was only negatively associated with satisfaction and investment, while workplace discrimination was negatively associated with alternatives. Moreover, both relationship satisfaction and investment influenced commitment which predicted persistence in these relationships over about seven years’ time, demonstrating support for the Investment Model. Our findings support the addition of sexual minority stress variables to the Investment Model when examining same-sex relationships and implications are discussed. PMID:28695154

  11. A Case of Pseudo-Retardation.

    ERIC Educational Resources Information Center

    Stott, D. H.

    Review of a case study of a 4-year-old girl who assumed the role of a retardate reveals that the girl probably suffered multiple congenital impairments of a minor character that affected the central nervous system and the structures governing social behavior and maturation. The stated basis for pseudo-retardation is the person's ability to…

  12. Groundstory vegetation response to different thinning intensities in a minor stream bottom in Mississippi: a preliminary analysis

    Treesearch

    Brent R. Frey; Ellen M. Boerger

    2015-01-01

    Groundstory vegetation typically accounts for the greatest proportion of plant diversity in temperate forests, representing a critical structural component and mediating numerous ecosystem processes, including tree regeneration. The effects of thinning on groundstory vegetation have received limited study in bottomland hardwood stands. This study investigated...

  13. Talking the Talk, Not Walking the Walk: Expressions from Underrepresented Students about Their Counselor Education Doctoral Programs

    ERIC Educational Resources Information Center

    Baker, Caroline Ann

    2010-01-01

    This qualitative study explored the perceptions of self-identified racial or ethnic minorities about their counselor education doctoral programs in relation to multicultural competence. More specifically, semi-structured interview questions were used to obtain information about their doctoral experiences related to faculty and peer relationships,…

  14. Masculinities in Organizational Cultures in Engineering Education in Europe: Results of the European Union Project WomEng

    ERIC Educational Resources Information Center

    Sagebiel, F.; Dahmen, J.

    2006-01-01

    The paper describes elements of engineering organizational cultures and structures in higher engineering education from the European project WomEng. Hypotheses, based on state of the art, refer to: women friendly presentation, attractiveness of interdisciplinary teaching methods, single sex education, perceptions of minority status, feelings of…

  15. Urban Decline or Disinvestment: Uneven Development, Redlining and the Role of the Insurance Industry.

    ERIC Educational Resources Information Center

    Squires, Gregory D.; And Others

    1979-01-01

    Redlining of many urban communities and discrimination against the poor and minorities are common in the insurance industry, and these practices contribute to the deterioration of those communities. The utilization of a structural/disinvestment approach by social scientists should provide additional information about the uneven development of…

  16. The "Ever Green" Interpretations of the "Library Bill of Rights"

    ERIC Educational Resources Information Center

    Adams, Helen R.

    2010-01-01

    The American Library Association's (ALA) "Library Bill of Rights" is important to school librarians because it provides the philosophical structure for intellectual freedom in school libraries and asserts the rights of minors. It states: "A person's right to use a library should not be denied or abridged because of origin, age,…

  17. Advanced Placement Course Enrollment and School-Level Characteristics

    ERIC Educational Resources Information Center

    Barnard-Brak, Lucy; McGaha-Garnett, Valerie; Burley, Hansel

    2011-01-01

    The current study examined access to Advanced Placement (AP) courses as a function of these school characteristics (e.g., percentage of ethnic minority and lower socioeconomic status) and then examined AP course enrollment as a function of both access to AP courses and these school characteristics. Using structural equation modeling techniques,…

  18. What Should We Know about Developmental Education?

    ERIC Educational Resources Information Center

    Lake, Pat, Ed.

    2001-01-01

    This document argues that the availability of developmental education is essential to the well being of the American economy and social structure. By the year 2050, U.S. citizens will be older and nearly 50% will belong to a minority group. The fastest growing population is Hispanic American, resulting from immigration and higher birth rates. This…

  19. 46 CFR 190.07-90 - Vessels contracted for prior to March 1, 1968.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... considered satisfactory so long as they are maintained in good condition to the satisfaction of the Officer in Charge, Marine Inspection. Minor repairs and alterations may be made to the same standards as the... VESSELS CONSTRUCTION AND ARRANGEMENT Structural Fire Protection § 190.07-90 Vessels contracted for prior...

  20. The Forest Indians in the Present Political Situation of Peru.

    ERIC Educational Resources Information Center

    Varese, Stefano

    The article focuses on tribal minorities (American Indians) of the Peruvian tropical forest from the point of view of the political circumstances and the general administrative conditions of the country. In 1968 the revolutionary military government initiated a series of structural reforms which aimed at transforming Peru. This article poses and…

  1. DIFFERENCES IN THE STRUCTURE AND FUNCTION OF FATHEAD MINNOW AND HUMAN ERA: IMPLICATIONS FOR IN VITRO TESTING OF ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    Mammalian receptors and assay systems are generally used for in vitro analysis of endocrine disrupting chemicals (EDC) with the assumption that minor differences in amino acid sequences among species do not translate into significant differences in receptor function. We have fou...

  2. Serbian: The Serbian Language in Education in Hungary. Regional Dossiers Series

    ERIC Educational Resources Information Center

    Paulik, Anton, Comp.; Solymosi, Judit, Comp.

    2014-01-01

    This regional dossier aims at providing a concise description of and basic statistics on minority language education in a specific region of Europe--the territory of Magyarország (Hungary). Aspects that are addressed include features of the education system, recent educational policies, main actors, legal arrangements, and support structures, as…

  3. Characteristics and availability of commercially important woods

    Treesearch

    Regis B. Miller

    1999-01-01

    Throughout history, the unique characteristics and comparative abundance of wood have made it a natural material for homes and other structures, furniture, tools, vehicles, and decorative objects. Today, for the same reasons, wood is prized for a multitude of uses. All wood is composed of cellulose, lignin, hemicelluloses, and minor amounts (5% to 10%) of extraneous...

  4. Concentrated Contract Learning: A Working Paper.

    ERIC Educational Resources Information Center

    Staten Island Community Coll., NY.

    The traditional approaches and structures of career programs must be made more relevant to students whose primary aim is obtaining a decent, satisfying job upon graduation. Educational innovations have represented an elitist view, and the aspirations of the "new students" from low-income and/or minority groups to obtain jobs that are not demeaning…

  5. Public Higher Education Governing Boards: The Role of Social Networks

    ERIC Educational Resources Information Center

    Miller, Emily R.

    2011-01-01

    A defining feature of American higher education is the provision for authority over the institution by an external governing board consisting of lay members of the public (Thelin, 2004). Studies of higher education governing boards typically focus on structure and performance (Kezar & Eckel, 2004; Kezar, 2006; McGuinness, 2003; Minor, 2006;…

  6. Minority Views on the Report of the Commission on Opportunity in Athletics.

    ERIC Educational Resources Information Center

    de Varona, Donna; Foudy, Julie

    This report asserts that there are several findings and recommendations which have been included in the Commission on Opportunity in Athletics' report, which made recommendations for substantial changes to current Title IX guidelines and policies. It fundamentally disagrees with the tenor, structure, and significant portions of the content of the…

  7. Blueprint for the Assessment of Socio-Structural Influences in Career Choice and Decision Making.

    ERIC Educational Resources Information Center

    Brown, Michael T.

    2000-01-01

    In the context of societal racism, sexism, and classism, career assessment of women and minority groups should take into account sociostructural realities and their psychological effects. Factors include the objective and subjective realities of the economic, social status, and social power domains. (Contains 33 references.) (SK)

  8. Gender and Race, Online Communities, and Composition Classrooms

    ERIC Educational Resources Information Center

    Morris, Jill

    2011-01-01

    As the culmination of a two-year long Internet ethnographic study of three separate sites, I use examples of women and minorities fighting against discrimination online to explore the power structures inherent to networks and how these might affect classroom practice. I will show how our ordinary assumptions in rhetoric and composition as well as…

  9. Reproducing Monocultural Education: Ethnic Majority Staff's Discursive Constructions of Monocultural School Practices

    ERIC Educational Resources Information Center

    Mampaey, Jelle; Zanoni, Patrizia

    2016-01-01

    This paper investigates the role of ethnic majority staff in the perpetuation of monocultural education that excludes non-western, ethnic minority cultures and reproduces institutional racism in schools. Based on qualitative data collected through semi-structured interviews in four ethnically diverse schools in the Flemish educational system, we…

  10. Arecibo weathers the storm

    NASA Astrophysics Data System (ADS)

    Rivera-Valentín, Edgard G.; Schmelz, Joan T.

    2018-04-01

    Hurricane Maria was 2 mph short of category 5 when it made landfall on Puerto Rico on 20 September 2017. The 305 m radio telescope at the Arecibo Observatory withstood the storm, suffering only minor structural damage. Staff have worked diligently to return the site to full operations and provide vital services to the surrounding Puerto Rican community.

  11. Relations between Neighborhood Factors, Parenting Behaviors, Peer Deviance, and Delinquency among Serious Juvenile Offenders

    ERIC Educational Resources Information Center

    Chung, He Len; Steinberg, Laurence

    2006-01-01

    The present study examined relations among neighborhood structural and social characteristics, parenting practices, peer group affiliations, and delinquency among a group of serious adolescent offenders. The sample of 14-18-year-old boys (N = 488) was composed primarily of economically disadvantaged, ethnic-minority youth living in urban…

  12. 15 CFR Appendix B to Subpart R of... - Minor Projects for Purposes of § 922.193(a)(2)(iii)

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...), the Michigan Department of Environmental Quality (Department) issues permits for projects that are of... values or interests, including navigation and water quality. (h) Fish or wildlife habitat structures..., water monitoring devices, water quality testing devices, survey devices, and core sampling devices, if...

  13. Friulian: The Friulian Language in Education in Italy. Regional Dossiers Series

    ERIC Educational Resources Information Center

    Petris, Cinzia, Comp.

    2014-01-01

    This regional dossier aims to provide a concise, description and basic statistics about minority language education in a specific region of Europe. Aspects that are addressed include features of the education system, recent educational policies, main actors, legal arrangements, and support structures, as well as quantitative aspects, such as the…

  14. Catalan: The Catalan Language in Education in Spain, 2nd Edition. Regional Dossiers Series

    ERIC Educational Resources Information Center

    Areny, Maria, Comp.; Mayans, Pere, Comp.; Forniès, David, Comp.

    2013-01-01

    Regional dossiers aim at providing a concise description and basic statistics about minority language education in a specific region of Europe. Aspects that are addressed include features of the education system, recent educational policies, main actors, legal arrangements, and support structures, as well as quantitative aspects, such as the…

  15. The Structure of the Metal Transporter Tp34 and its Affinity for Divalent Metal Ions

    NASA Astrophysics Data System (ADS)

    Knutsen, Gregory; Deka, Ranjit; Brautigam, Chad; Tomchick, Diana; Machius, Mischa; Norgard, Michael

    2007-10-01

    Tp34 is periplasmic membrane protein of the nonculitvatable spirochete Treponema pallidum, the pathogen of syphillis. It was proposed that Tp34 is a divalent metal transporter, but the identity of the preferred metal ion(s) was unclear. In this study we investigated the ability of divalent metal ions to induce rTp34 dimerization using hydrodynamic techniques and determine the crystal structure of metal bound forms. Using analytical ultracentrifugation sedimentation velocity experiments, we determined that cobalt is superior to nickel at inducing the dimerization of rTp34. rTp34 was crystallized and selected crystals were incubated at a pH 7.5 with CuSO4 and NiSO4. Diffraction experiments were conducted and the processed electron density maps showed that copper was bound to the major metal binding site as well as to three additional minor binding sites. By contrast nickel was only bound to the major metal binding site in one monomer and to three additional minor sites. These results along with previous findings support evidence of Tp34 being involved with metal transport and/or iron utilization.

  16. First observations of minority ion (H+) structuring in stimulated radiation during second electron gyroharmonic heating experiments

    NASA Astrophysics Data System (ADS)

    Bordikar, M. R.; Scales, W. A.; Samimi, A. R.; Bernhardt, P. A.; Brizcinski, S.; McCarrick, M. J.

    2013-04-01

    This work presents the first observations of unique narrowband emissions ordered near the hydrogen ion (H+) gyrofrequency (fcH) in the stimulated electromagnetic emission spectrum when the transmitter is tuned near the second electron gyroharmonic frequency (2fce) during ionospheric modification experiments. The frequency structuring of these newly discovered emission lines is quite unexpected since H+ is known to be a minor constituent in the interaction region which is near 160 km altitude. The spectral lines are typically shifted from the pump wave frequency by harmonics of a frequency about 10% less than fcH (≈ 800 Hz) and have a bandwidth of less than 50 Hz which is near the O+ gyrofrequency fcO. A theory is proposed to explain these emissions in terms of a parametric decay instability in a multi-ion species plasma due to possible proton precipitation associated with the disturbed conditions during the heating experiment. The observations can be explained by including several percent H+ ions into the background plasma. The implications are new possibilities for characterizing proton precipitation events during ionospheric heating experiments.

  17. Micromechanics of Minor Cervical Spine Injuries

    NASA Astrophysics Data System (ADS)

    Niederer, Peter F.; Schmitt, Kai-Uwe; Muser, Markus H.; Walz, Felix H.

    Minor soft tissue injuries of the cervical spine are of increasing significance in public health. They may in particular be associated with long-term impairment. Such injuries are observed primarily in rear-end automobile collisions at low impact speeds and are attributed to a “whiplash”-type event. The question with respect to injury mechanisms of the cervical spine in cases of impacts of a low severity have raised controversial views in the past. Among proposed injury mechanisms, interactions between fluid and solid structures have been postulated: Viscous shear stresses or pressure gradients which arise in the deforming anatomical structures may have an adverse influence, e. g., on cellular membranes. In this communication, mathematical modeling approaches are presented which allow for a quantification of fluid/solid interactions under typical loading conditions of interest here. It is found, that the shear stresses caused by fluids and acting on accelerated surfaces of fluid-filled bodies depend largely on the size of the fluid space under consideration. Accelerations exhibit a stronger influence than their duration. It cannot be excluded that critical levels are reached even in a low speed impact scenario.

  18. [Changes in Spatial Organization of Cortical Rhythm Vibrations in Children uner the Influence of Music].

    PubMed

    Shepovalnikov, A N; Egorov, M V

    2015-01-01

    Changes is systemic brain activity under influence of classical music (minor and major music) were studied at two groups of healthy children aged 5-6 years (n = 53). In 25 of studied children the Luscher test showed increased level of anxiety which significantly decreased after music therapy sessions. Bioelectrical cortical activity registered from 20 unipolar leads was subjected to correlation, coherence and factor analysis. Also the dynamics of the power spectrum for each of the EEG was studied. According to EEG all children after listening to both minor and major tones showed reorganization of brain rhythm structure accompanied by a decrease in the level of coherence and correlation of EEG; also was found significant and almost universal decrease in the EEG power spectrum. Registered EEG changes under the influence of classical music seems to reflect a decrease in excess of "internal tension" and weakening degree of "stiffness" to ensure the activity of cerebral structures responsible for mechanisms of "basic integration" which maintain constant readiness of brain to rapid and complete inclusion in action.

  19. How grain boundaries affect the efficiency of poly-CdTe solar-cells: A fundamental atomic-scale study of grain boundary dislocation cores using CdTe bi-crystal thin films.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Klie, Robert

    It is now widely accepted that grain boundaries in poly-crystalline CdTe thin film devices have a detrimental effect on the minority carrier lifetimes, the open circuit voltage and therefore the overall solar-cell performance. The goal of this project was to develop a fundamental understanding of the role of grain boundaries in CdTe on the carrier life-time, open-circuit voltage, Voc, and the diffusion of impurities. To achieve this goal, i) CdTe bi-crystals were fabricated with various misorientation angels, ii) the atomic- and electronic structures of the grain boundaries were characterized using scanning transmission electron microscopy (STEM), and iii) first-principles density functionalmore » theory modeling was performed on the structures determined by STEM to predict the grain boundary potential. The transport properties and minority carrier lifetimes of the bi-crystal grain boundaries were measured using a variety of approaches, including TRPL, and provided feedback to the characterization and modeling effort about the effectiveness of the proposed models.« less

  20. Magnetic field tunability of spin polarized excitations in a high temperature magnet

    NASA Astrophysics Data System (ADS)

    Holinsworth, Brian; Sims, Hunter; Cherian, Judy; Mazumdar, Dipanjan; Harms, Nathan; Chapman, Brandon; Gupta, Arun; McGill, Steve; Musfeldt, Janice

    Magnetic semiconductors are at the heart of modern device physics because they naturally provide a non-zero magnetic moment below the ordering temperature, spin-dependent band gap, and spin polarization that originates from exchange-coupled magnetization or an applied field creating a spin-split band structure. Strongly correlated spinel ferrites are amongst the most noteworthy contenders for semiconductor spintronics. NiFe2O4, in particular, displays spin-filtering, linear magnetoresistance, and wide application in the microwave regime. To unravel the spin-charge interaction in NiFe2O4, we bring together magnetic circular dichroism, photoconductivity, and prior optical absorption with complementary first principles calculations. Analysis uncovers a metamagnetic transition modifying electronic structure in the minority channel below the majority channel gap, exchange splittings emerging from spin-split bands, anisotropy of excitons surrounding the indirect gap, and magnetic-field dependent photoconductivity. These findings open the door for the creation and control of spin-polarized excitations from minority channel charge charge transfer in NiFe2O4 and other members of the spinel ferrite family.

Top