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Sample records for hiv discordant unions

  1. Experience of sexual violence among women in HIV discordant unions after voluntary HIV counselling and testing

    PubMed Central

    Emusu, Donath; Ivankova, Nataliya; Jolly, Pauline; Kirby, Russell; Foushee, Herman; Wabwire-Mangen, Fred; Katongole, Drake; Ehiri, John

    2009-01-01

    HIV-serodiscordant relationships are those in which one partner is infected with HIV while the other is not. We investigated experiences of sexual violence among women in HIV discordant unions attending HIV post-test club services in Uganda. A volunteer sample of 26 women from three AIDS Information Centres in Uganda who reported having experienced sexual violence in a larger epidemiological study were interviewed, using the qualitative critical incident technique. Data were analysed using TEXTPACK, a software application for computer-assisted content analysis. Incidents of sexual violence narrated by the women included use of physical force and verbal threats. Overall, four themes that characterise the women’s experience of sexual violence emerged from the analysis: knowledge of HIV test results, prevalence of sexual violence, vulnerability and proprietary views and reactions to sexual violence. Alcohol abuse by the male partners was an important factor in the experience of sexual violence among the women. Their experiences evoked different reactions and feelings, including concern over the need to have children, fear of infection, desire to separate from their spouses/partners, helplessness, anger and suicidal tendencies. HIV counselling and testing centres should be supported with the capacity to address issues related to sexual violence for couples who are HIV discordant. PMID:20024712

  2. Experience of sexual violence among women in HIV discordant unions after voluntary HIV counselling and testing: a qualitative critical incident study in Uganda.

    PubMed

    Emusu, Donath; Ivankova, Nataliya; Jolly, Pauline; Kirby, Russell; Foushee, Herman; Wabwire-Mangen, Fred; Katongole, Drake; Ehiri, John

    2009-11-01

    HIV-serodiscordant relationships are those in which one partner is infected with HIV while the other is not. We investigated experiences of sexual violence among women in HIV discordant unions attending HIV post-test club services in Uganda. A volunteer sample of 26 women from three AIDS Information Centres in Uganda who reported having experienced sexual violence in a larger epidemiological study were interviewed, using the qualitative critical incident technique. Data were analysed using TEXTPACK, a software application for computer-assisted content analysis. Incidents of sexual violence narrated by the women included use of physical force and verbal threats. Overall, four themes that characterise the women's experience of sexual violence emerged from the analysis: knowledge of HIV test results, prevalence of sexual violence, vulnerability and proprietary views and reactions to sexual violence. Alcohol abuse by the male partners was an important factor in the experience of sexual violence among the women. Their experiences evoked different reactions and feelings, including concern over the need to have children, fear of infection, desire to separate from their spouses/partners, helplessness, anger and suicidal tendencies. HIV counselling and testing centres should be supported with the capacity to address issues related to sexual violence for couples who are HIV discordant. PMID:20024712

  3. Prevalence and predictors of HIV sero-discordance among cohabiting couples tested in northern Tanzania

    PubMed Central

    Ngilangwa, David Paul; Ochako, Rhoune; Mboya, Beati Alphonce; Noronha, Rita Honoratha; Mgomella, George Suleman

    2015-01-01

    Introduction In sub-Saharan Africa where HIV/AIDS epidemic is predominantly generalized, majority of HIV infections occur among heterosexual couples. The majority of people do not know their sero-status. Thus, utilisation of Couples’ HIV Counselling and Testing (CHCT) services remain to be critical in preventing new infections. The objective was to establish prevalence and predictors of HIV sero-discordance among cohabiting couples presenting for CHCT services in northern Tanzania. Methods A cross-sectional study inteveviewed 1,333 couples aged 18-49 years tested from 2005 to 2007 in Kilimanjaro and Arusha regions. A CHCT checklist was used to collect data from couples. Data were analyzed using STATA 10. Results Generally, 220(16%) out of 1,333 couples were HIV sero-discordant. In sero-discordance unions, women were likely to be HIV positive than men (71% versus 29% respectively p<0.001). HIV sero-discordant relationship was associated with age (35-45 years) for both men and women (Adjusted Odds Ratio (AOR): 2.3, 95% Confidence Interval (CI): 1.7-3.2) and (AOR: 2.6, 95% CI 1.9-3.7) respectively. Women with older men partners were less likely to be in HIV sero-discordance relationships (AOR: 0.5 95% CI 0.3-09). Arusha couples were likely to be HIV sero-discordant than those of Kilimanjaro (AOR: 2.3 95% CI 1.7-3.2). Couples living far away from CHCT centres were less likely to be sero-discordant than those live nearby (AOR: 0.4 95% CI 0.2-0.9). Conclusion HIV sero-discordance prevalence is high among our participants. Thus, we recommend CHCT utilization should widely be promoted as entry point in treatment as prevention strategy in order to protect uninfected partners in HIV sero-discordance relationships. PMID:26958138

  4. Past present: Relationship dynamics may differ among discordant gay male couples depending on HIV infection history

    PubMed Central

    Beougher, Sean C.; Mandic, Carmen Gómez; Darbes, Lynae A.; Chakravarty, Deepalika; Neilands, Torsten B.; Garcia, Carla C.; Hoff, Colleen C.

    2013-01-01

    Discordant couples are unique because neither partner shares the same serostatus. Yet research overlooks how they became discordant, mistakenly assuming that they have always been that way and, by extension, that being discordant impacts the relationship in a similar manner. This study examines HIV infection history and its impact on relationship dynamics using qualitative data from 35 discordant gay male couples. Most couples met discordant (69%); however, many did not (31%). Those couples that met discordant felt being discordant had a lesser impact on their sexual and relational satisfaction, while those that did not meet discordant felt it had a greater impact, reporting sexual frustration and anxiety over seroconverting. This suggests that relationship dynamics may differ for discordant couples depending on HIV infection history. HIV prevention and counseling services for discordant couples can be better tailored and more effective when differences in HIV infection history are recognized. PMID:24244082

  5. Past present: Relationship dynamics may differ among discordant gay male couples depending on HIV infection history.

    PubMed

    Beougher, Sean C; Mandic, Carmen Gómez; Darbes, Lynae A; Chakravarty, Deepalika; Neilands, Torsten B; Garcia, Carla C; Hoff, Colleen C

    2013-10-01

    Discordant couples are unique because neither partner shares the same serostatus. Yet research overlooks how they became discordant, mistakenly assuming that they have always been that way and, by extension, that being discordant impacts the relationship in a similar manner. This study examines HIV infection history and its impact on relationship dynamics using qualitative data from 35 discordant gay male couples. Most couples met discordant (69%); however, many did not (31%). Those couples that met discordant felt being discordant had a lesser impact on their sexual and relational satisfaction, while those that did not meet discordant felt it had a greater impact, reporting sexual frustration and anxiety over seroconverting. This suggests that relationship dynamics may differ for discordant couples depending on HIV infection history. HIV prevention and counseling services for discordant couples can be better tailored and more effective when differences in HIV infection history are recognized. PMID:24244082

  6. Delayed initiation of antiretroviral therapy among HIV-discordant couples in Kenya.

    PubMed

    Kahn, Talia R; Desmond, Michelle; Rao, Deepa; Marx, Grace E; Guthrie, Brandon L; Bosire, Rose; Choi, Robert Y; Kiarie, James N; Farquhar, Carey

    2013-01-01

    Timely initiation of antiretroviral therapy (ART) is particularly important for HIV-discordant couples because viral suppression greatly reduces the risk of transmission to the uninfected partner. To identify issues and concerns related to ART initiation among HIV-discordant couples, we recruited a subset of discordant couples participating in a longitudinal study in Nairobi to participate in in-depth interviews and focus group discussions about ART. Our results suggest that partners in HIV-discordant relationships discuss starting ART, yet most are not aware that ART can decrease the risk of HIV transmission. In addition, their concerns about ART initiation include side effects, sustaining an appropriate level of drug treatment, HIV/AIDS-related stigma, medical/biological issues, psychological barriers, misconceptions about the medications, the inconvenience of being on therapy, and lack of social support. Understanding and addressing these barriers to ART initiation among discordant couples is critical to advancing the HIV "treatment as prevention" agenda. PMID:22866934

  7. Determination of HIV status in African adults with discordant HIV rapid tests

    PubMed Central

    Fogel, Jessica M.; Piwowar-Manning, Estelle; Donohue, Kelsey; Cummings, Vanessa; Marzinke, Mark A.; Clarke, William; Breaud, Autumn; Fiamma, Agnès; Donnell, Deborah; Kulich, Michal; Mbwambo, Jessie K. K.; Richter, Linda; Gray, Glenda; Sweat, Michael; Coates, Thomas J.; Eshleman, Susan H.

    2015-01-01

    Background In resource-limited settings, HIV infection is often diagnosed using two rapid tests. If the results are discordant, a third tie-breaker test is often used to determine HIV status. This study characterized samples with discordant rapid tests and compared different testing strategies for determining HIV status in these cases. Methods Samples were previously collected from 173 African adults in a population-based survey who had discordant rapid test results. Samples were classified as HIV positive or HIV negative using a rigorous testing algorithm that included two fourth-generation tests, a discriminatory test, and two HIV RNA tests. Tie-breaker tests were evaluated, including: rapid tests (one performed in-country), a third-generation enzyme immunoassay (EIA), and two fourth-generation tests. Selected samples were further characterized using additional assays. Results Twenty-nine (16.8%) samples were classified as HIV positive; 24 (82.8%) of those samples had undetectable HIV RNA. Antiretroviral drugs were detected in one sample. Sensitivity was 8.3%–43% for the rapid tests; 24.1% for the third-generation EIA; 95.8% and 96.6% for the fourth-generation tests. Specificity was lower for the fourth-generation tests than the other tests. Accuracy ranged from 79.5–91.3%. Conclusions In this population-based survey, most HIV-infected adults with discordant rapid tests were virally suppressed without antiretroviral drugs. Use of individual assays as tie-breaker tests was not a reliable method for determining HIV status in these individuals. More extensive testing algorithms that use a fourth-generation screening test with a discriminatory test and HIV RNA test are preferable for determining HIV status in these cases. PMID:25835607

  8. The prevalence of HSV-2 infection in HIV-1 discordant couples.

    PubMed

    Duan, S; Ding, Y; Wu, Z; Rou, K; Yang, Y; Wang, J; Gao, M; Ye, R; Xiang, L; He, N

    2016-01-01

    We aimed to investigate the prevalence and associated factors of HSV-2 discordance and concordance in HIV-1-discordant couples. This study used the baseline data from a cohort study of HIV-1-discordant couples in Dehong prefecture of Yunnan province, China. Of 954 participating couples, 42·4% were affected by HSV-2, of which 20·4% were HSV-2-concordant positive, 7·6% were HSV-2-discordant where the male was HSV-2 positive, and 14·4% were HSV-2 discordant where the female was HSV-2 positive. Compared to HSV-2-negative concordance, HSV-2 discordance with an HSV-2-positive male spouse was significantly associated with characteristics of the male spouse, including Han ethnicity and being in a second marriage. HSV-2 discordance with an HSV-2-positive female spouse was significantly associated with characteristics of the female spouse, including Han ethnicity, having engaged in commercial sex, having a sexual relationship of <3 years and being HIV-1 infected. Compared to HSV-2 discordance, HSV-2-positive concordance was significantly associated with an education level of middle school or higher for both spouses, a sexual relationship of ⩾3 years, more frequent sex and having an HIV-1-infected male spouse. The findings highlight the need for HSV-2 prevention and treatment efforts to reduce HSV-2 transmission in this population, and emphasize the importance of implementing prevention interventions early in couples' relationships. PMID:26113166

  9. Discordance

    NASA Astrophysics Data System (ADS)

    Villa, I. M.; Hanchar, J. M.

    2013-12-01

    Half a century ago, discordant U-Pb ages of metamorphic zircon were viewed as Pb loss by diffusion. Various diffusionist schools of thought debated vigorously whether diffusion was episodic or continuous [1], but nobody questioned the reality of diffusive Pb loss. Only imaging by cathodoluminescence (CL) [2] and back-scattered electrons (BSE) [3] brought a paradigm change in U-Pb geochronology. In situ dating shows routinely accretion of young zircon rims onto older cores that never display Pb diffusion gradients across the interface. Other minerals (monazite, xenotime, etc.) show the same pattern: irregular patches of uniform age separated by sharp age gradients coinciding with petrologic boundaries. As U-Pb discordance is caused by diachronous, heterochemical mineral generations, zircon and monazite closure temperatures, and strict diffusionism, are irrelevant [4]. Knowing what to pay attention to, analytical protocols for U-Pb dating include both of the following: (i) CL/BSE characterization of phase mixtures; (ii) mass spectrometric analysis including U/Th ratios (and ideally trace element fingerprinting on the same fraction [5]). It is clear that the petrologic context is just as essential as mass spectrometry for accurate geochronology. The K-Ar community rarely uses imaging, and the tight context between microstructures, mineral chemistry, petrology and geochronology is missed. Yet the data would be clear if one looked for it. CL and/or BSE imaging and X-ray mapping of K-feldspar and micas is finding ubiquitous evidence of discrete patches of juxtaposed mineral generations. The Ca/Cl/K ratios in 39Ar-40Ar dating fulfill the same role as U/Th ratios in U-Pb dating for fingerprinting successive heterochemical mineral generations. Any linear correlation in a common-denominator three-isotope correlation diagram is certain evidence of binary mixing between heterochemical end-members. A correlation in a Ca/K vs Ar/K diagram requires two minerals having different

  10. HIV and HCV discordant injecting partners and their association to drug equipment sharing.

    PubMed

    De, Prithwish; Cox, Joseph; Boivin, Jean-Francois; Platt, Robert W; Jolly, Ann M; Alexander, Paul E

    2009-01-01

    Our objective was to examine the association between HIV and HCV discordant infection status and the sharing of drug equipment by injection drug users (IDUs). IDUs were recruited from syringe exchange and methadone treatment programmes in Montreal, Canada. Characteristics of participants and their injecting partners were elicited using a structured questionnaire. Among 159 participants and 245 injecting partners, sharing of syringes and drug preparation equipment did not differ between concordant or discordant partners, although HIV-positive subjects did not share with HIV-negative injectors. Sharing of syringes was positively associated with discordant HIV status (OR=1.85) and negatively with discordant HCV status (OR=0.65), but both results were not statistically significant. Sharing of drug preparation equipment was positively associated with both discordant HIV (OR=1.61) and HCV (OR=1.18) status, but both results were non-significant. Factors such as large injecting networks, frequent mutual injections, younger age, and male gender were stronger predictors of equipment sharing. In conclusion, IDUs do not appear to discriminate drug equipment sharing partners based at least on their HCV infection status. The results warrant greater screening to raise awareness of infection status, post-test counselling to promote status disclosure among partners, and skill-building to avoid equipment sharing between discordant partners. PMID:19172434

  11. Motivations to test for HIV among partners in concordant HIV-negative and HIV-discordant gay male couples.

    PubMed

    Beougher, Sean C; Bircher, Anja E; Chakravarty, Deepalika; Darbes, Lynae A; Mandic, Carmen Gómez; Neilands, Torsten B; Garcia, Carla C; Hoff, Colleen C

    2015-02-01

    Previous studies of HIV testing among gay men describe the motivations, facilitators and barriers, behaviors, and demographic characteristics of individuals who test. What little research focuses on HIV testing among gay men in relationships shows that they do not test regularly or, in some cases, at all-their motivations to test have not been investigated. With so little data on HIV testing for this population, and the continued privileging of individually focused approaches, gay men in relationships fall into a blind spot of research and prevention efforts. This study examined motivations to test for HIV using qualitative data from both partners in 20 gay male couples. Analysis revealed that the partners' motivations were either event-related (e.g., participants testing at the beginning of their relationship or HIV-negative participants in an HIV-discordant relationship testing after risky episode with their discordant primary partner) or partner-related (e.g., participants testing in response to a request or suggestion to test from their primary partner or participants testing out of concern for their primary partner's health and well-being). These data provide insight into relationship-oriented motivations to test for HIV for gay men in relationships and, in doing so, evidence their commitment to their primary partner and relationship. These motivations can be leveraged to increase HIV testing among gay men in relationships, a population that tests less often than single gay men, yet, until recently, has been underserved by prevention efforts. PMID:25550145

  12. Antiretroviral therapy for prevention of HIV transmission in HIV-discordant couples

    PubMed Central

    Anglemyer, Andrew; Rutherford, George W; Horvath, Tara; Baggaley, Rachel C; Egger, Matthias; Siegfried, Nandi

    2014-01-01

    Background Antiretroviral drugs have been shown to reduce risk of mother-to-child transmission of human immunodeficiency virus (HIV) and are also widely used for post-exposure prophylaxis for parenteral and sexual exposures. Sexual transmission may be lower in couples in which one partner is infected with HIV and the other is not and the infected partner is on antiretroviral therapy (ART). Objectives To determine if ART use in an HIV-infected member of an HIV-discordant couple is associated with lower risk of HIV transmission to the uninfected partner compared to untreated discordant couples. Search methods We used standard Cochrane methods to search electronic databases and conference proceedings with relevant search terms without limits to language. Selection criteria Randomised controlled trials (RCT), cohort studies and case-control studies of HIV-discordant couples in which the HIV-infected member of the couple was being treated or not treated with ART Data collection and analysis Abstracts of all trials identified by electronic or bibliographic scanning were examined independently by two authors. We initially identified 3,833 references and examined 87 in detail for study eligibility. Data were abstracted independently using a standardised abstraction form. Main results One RCT and nine observational studies were included in the review. These ten studies identified 2,112 episodes of HIV transmission, 1,016 among treated couples and 1,096 among untreated couples. The rate ratio for the single randomised controlled trial was 0.04 [95% CI 0.00, 0.27]. All index partners in this study had CD4 cell counts at baseline of 350–550 cells/µL. Similarly, the summary rate ratio for the nine observational studies was 0.58 [95% CI 0.35, 0.96], with substantial heterogeneity (I2=64%). After excluding two studies with inadequate person-time data, we estimated a summary rate ratio of 0.36 [95%CI 0.17, 0.75] with substantial heterogeneity (I2=62%). We also performed

  13. Antiretroviral Therapy Reduces HIV Transmission in Discordant Couples in Rural Yunnan, China

    PubMed Central

    He, Na; Duan, Song; Ding, Yingying; Rou, Keming; McGoogan, Jennifer M.; Jia, Manhong; Yang, Yuecheng; Wang, Jibao; Montaner, Julio S. G.; Wu, Zunyou

    2013-01-01

    Background Although HIV treatment as prevention (TasP) via early antiretroviral therapy (ART) has proven to reduce transmissions among HIV-serodiscordant couples, its full implementation in developing countries remains a challenge. In this study, we determine whether China's current HIV treatment program prevents new HIV infections among discordant couples in rural China. Methods A prospective, longitudinal cohort study was conducted from June 2009 to March 2011, in rural Yunnan. A total of 1,618 HIV-discordant couples were eligible, 1,101 were enrolled, and 813 were followed for an average of 1.4 person-years (PY). Routine ART was prescribed to HIV-positive spouses according to eligibility (CD4<350 cells/µl). Seroconversion was used to determine HIV incidence. Results A total of 17 seroconversions were documented within 1,127 PY of follow-up, for an overall incidence of 1.5 per 100 PY. Epidemiological and genetic evidence confirmed that all 17 seroconverters were infected via marital secondary sexual transmission. Having an ART-experienced HIV-positive partner was associated with a lower rate of seroconvertion compared with having an ART-naïve HIV-positive partner (0.8 per 100 PY vs. 2.4 per 100 PY, HR = 0.34, 95%CI = 0.12–0.97, p = 0.0436). While we found that ART successfully suppressed plasma viral load to <400 copies/ml in the majority of cases (85.0% vs. 19.5%, p<0.0001 at baseline), we did document five seroconversions among ART-experienced subgroup. Conclusions ART is associated with a 66% reduction in HIV incidence among discordant couples in our sample, demonstrating the effectiveness of China's HIV treatment program at preventing new infections, and providing support for earlier ART initiation and TasP implementation in this region. PMID:24236010

  14. HIV-negative and HIV-discordant Gay Male Couples’ Use of HIV Risk-Reduction Strategies: Differences by Partner Type and Couples’ HIV-status

    PubMed Central

    Mitchell, Jason W.

    2014-01-01

    Previous research has found that gay men and other men who have sex with men (MSM) have adopted a variety of HIV risk-reduction strategies to engage in unprotected anal intercourse (UAI). However, whether gay male couples’ use these strategies within and out of their relationships remains unknown. The present national cross-sectional study collected dyadic data from an online sample of 275 HIV-negative and 58 discordant gay male couples to assess their use of these strategies, and whether their use of these strategies had differed by partner type and couples’ HIV-status. The sample used a variety of risk-reduction strategies for UAI. Some differences and patterns by partner type and couples’ HIV status were detected about men’s use of these strategies. Findings indicate the need to bolster HIV prevention and education with gay male couples about their use of these strategies within and outside of their relationships. PMID:23247364

  15. Case series of fertility treatment in HIV-discordant couples (male positive, female negative): the Ontario experience.

    PubMed

    Newmeyer, Trent; Tecimer, Sandy N; Jaworsky, Denise; Chihrin, Steven; Gough, Kevin; Rachlis, Anita; Martin, James; Mohammed, Saira; Loutfy, Mona R

    2011-01-01

    The success of combination antiretroviral therapies for the treatment of human immunodeficiency virus (HIV) has resulted in prolonged life expectancy (over 40 years from diagnosis) and an improved quality of life for people living with HIV. The risk of vertical HIV transmission during pregnancy has been reduced to less than 1%. As a result of these breakthroughs and as many of these individuals are of reproductive age, fertility issues are becoming increasingly important for this population. One population in which conception planning and reduction of horizontal HIV transmission warrants further research is HIV-discordant couples where the male partner is HIV-positive and the female partner is HIV-negative. Sperm washing is a technique carried out in a fertility clinic that separates HIV from the seminal fluid. Although sperm washing followed by intrauterine insemination significantly reduces the risk of horizontal HIV transmission, there has been limited access to the procedure in North America. Furthermore, little is known about the conception decision-making experiences of HIV-discordant couples who might benefit from sperm washing. Chart reviews and semi-structured interviews were completed with 12 HIV-discordant couples in Ontario, Canada. Couples were recruited through HIV clinics and one fertility clinic that offered sperm washing. Participants identified a number of factors that affected their decision-making around pregnancy planning. Access to sperm washing and other fertility services was an issue (cost, travel and few clinics). Participants identified a lack of information on the procedure (availability, safety). Sources of support (social networks, healthcare providers) were unevenly distributed, especially among those who did not disclose their HIV status to friends and family. Finally, the stigmatisation of HIV continues to have a negative affect on HIV-discordant couples and their intentions to conceive. Access to sperm washing and fertility service

  16. Case Series of Fertility Treatment in HIV-Discordant Couples (Male Positive, Female Negative): The Ontario Experience

    PubMed Central

    Newmeyer, Trent; Tecimer, Sandy N.; Jaworsky, Denise; Chihrin, Steven; Gough, Kevin; Rachlis, Anita; Martin, James; Mohammed, Saira; Loutfy, Mona R.

    2011-01-01

    The success of combination antiretroviral therapies for the treatment of human immunodeficiency virus (HIV) has resulted in prolonged life expectancy (over 40 years from diagnosis) and an improved quality of life for people living with HIV. The risk of vertical HIV transmission during pregnancy has been reduced to less than 1%. As a result of these breakthroughs and as many of these individuals are of reproductive age, fertility issues are becoming increasingly important for this population. One population in which conception planning and reduction of horizontal HIV transmission warrants further research is HIV-discordant couples where the male partner is HIV-positive and the female partner is HIV-negative. Sperm washing is a technique carried out in a fertility clinic that separates HIV from the seminal fluid. Although sperm washing followed by intrauterine insemination significantly reduces the risk of horizontal HIV transmission, there has been limited access to the procedure in North America. Furthermore, little is known about the conception decision-making experiences of HIV-discordant couples who might benefit from sperm washing. Chart reviews and semi-structured interviews were completed with 12 HIV-discordant couples in Ontario, Canada. Couples were recruited through HIV clinics and one fertility clinic that offered sperm washing. Participants identified a number of factors that affected their decision-making around pregnancy planning. Access to sperm washing and other fertility services was an issue (cost, travel and few clinics). Participants identified a lack of information on the procedure (availability, safety). Sources of support (social networks, healthcare providers) were unevenly distributed, especially among those who did not disclose their HIV status to friends and family. Finally, the stigmatisation of HIV continues to have a negative affect on HIV-discordant couples and their intentions to conceive. Access to sperm washing and fertility service

  17. Qualitative Analysis of an Educational Intervention with HIV-Discordant Heterosexual Latino Couples

    PubMed Central

    Pérez-Jiménez, David; Orengo-Aguayo, Rosaura E.

    2012-01-01

    Objective This qualitative analysis elucidates the potential elements of the intervention that may be effective in terms of a) increasing knowledge about HIV/AIDS in the members of this population; b) increasing the use of male condoms and the practice of mutual masturbation; and c) changing opinions toward male condom use and mutual masturbation. Methods Five heterosexual HIV-discordant couples participated in the adapted intervention, which consisted of four three-hour-long sessions. One month after the intervention, we conducted a qualitative semi-structured interview with every participant to evaluate issues related to the process and content of the activities comprising the intervention, the impact of the intervention, logistics, and recruitment and retention as well as to make a more general evaluation. The information was submitted to qualitative content analysis. Results After the intervention, participants reported having better attitudes regarding safer sex, particularly in terms of condom use. A reason given by the participants to feel more positive toward condom use and mutual masturbation was that these practices could prevent the infection of the HIV-negative partner. Conclusion This study provides important evidence of an intervention that promises to be efficacious in preventing some high-risk sexual behaviors among Latino HIV-discordant heterosexual couples. The evidence presented seems to suggest that an intervention that includes basic relevant information about HIV/AIDS, that explains the benefits of condom use and other safer sex options, and that provides effective negotiation and communication strategies could significantly reduce HIV transmission among these couples. PMID:22263299

  18. 'We keep her status to ourselves': experiences of stigma and discrimination among HIV-discordant couples in South Africa, Tanzania and Ukraine.

    PubMed

    Rispel, Laetitia C; Cloete, Allanise; Metcalf, Carol A

    2015-01-01

    In HIV-discordant relationships, the HIV-negative partner also carries the burden of a stigmatised disease. For this reason, couples often hide their HIV-discordant status from family, friends and community members. This perpetuates the silence around HIV-discordant relationships and impacts on targeted HIV prevention, treatment and counselling efforts. This article reports on experiences of stigma and discrimination among HIV-discordant couples in South Africa, Tanzania and Ukraine. During 2008, HIV-discordant couples who had been in a relationship for at least one year were recruited purposively through health-care providers and civil society organisations in the three countries. Participants completed a brief self-administered questionnaire, while semi-structured interviews were conducted with each partner separately and with both partners together. Interviews were analysed using thematic content analysis. Fifty-one couples were recruited: 26 from South Africa, 10 from Tanzania, and 15 from Ukraine. Although most participants had disclosed their HIV status to someone other than their partner, few were living openly with HIV discordance. Experiences of stigma were common and included being subjected to gossip, rumours and name-calling, and HIV-negative partners being labelled as HIV-positive. Perpetrators of discrimination included family members and health workers. Stigma and discrimination present unique and complex challenges to couples in HIV sero-discordant relationships in these three diverse countries. Addressing stigmatisation of HIV-discordant couples requires a holistic human rights approach and specific programme efforts to address discrimination in the health system. PMID:25778765

  19. ‘We keep her status to ourselves’: Experiences of stigma and discrimination among HIV-discordant couples in South Africa, Tanzania and Ukraine

    PubMed Central

    Rispel, Laetitia C.; Cloete, Allanise; Metcalf, Carol A.

    2015-01-01

    Abstract In HIV-discordant relationships, the HIV-negative partner also carries the burden of a stigmatised disease. For this reason, couples often hide their HIV-discordant status from family, friends and community members. This perpetuates the silence around HIV-discordant relationships and impacts on targeted HIV prevention, treatment and counselling efforts. This article reports on experiences of stigma and discrimination among HIV-discordant couples in South Africa, Tanzania and Ukraine. During 2008, HIV-discordant couples who had been in a relationship for at least one year were recruited purposively through health-care providers and civil society organisations in the three countries. Participants completed a brief self-administered questionnaire, while semi-structured interviews were conducted with each partner separately and with both partners together. Interviews were analysed using thematic content analysis. Fifty-one couples were recruited: 26 from South Africa, 10 from Tanzania, and 15 from Ukraine. Although most participants had disclosed their HIV status to someone other than their partner, few were living openly with HIV discordance. Experiences of stigma were common and included being subjected to gossip, rumours and name-calling, and HIV-negative partners being labelled as HIV-positive. Perpetrators of discrimination included family members and health workers. Stigma and discrimination present unique and complex challenges to couples in HIV sero-discordant relationships in these three diverse countries. Addressing stigmatisation of HIV-discordant couples requires a holistic human rights approach and specific programme efforts to address discrimination in the health system. PMID:25778765

  20. Sequence analysis of the dimerization initiation site of concordant and discordant viral variants superinfecting HIV type 1 patients.

    PubMed

    Mayr, Luzia; Powell, Rebecca; Kinge, Thompson; Nyambi, Phillipe N

    2011-11-01

    For HIV recombination to occur, the RNAs from two infecting strains within a cell must dimerize at the dimerization initiation site (DIS). We examined the sequence identity at the DIS (697-731 bp, Hxb2 numbering engine) in patients superinfected with concordant HIV-1 strains and compared them to those with discordant strains. Viral RNA in sequential plasma from four subjects superinfected with subtype-discordant and two subjects superinfected with subtype-concordant HIV-1 strains was extracted, amplified (5' LTR-early gag: 526-1200 bp, Hxb2 numbering engine), sequenced, and analyzed to determine their compatibility for dimerization in vivo. The concordant viruses infecting the two subjects exhibited identical sequences in the 35-bp-long DIS region while sequences from the discordant viruses revealed single nucleotide changes that were located in the DIS loop (715 bp), its flanking nucleotides (710 bp and 717 bp), and the DIS stem (719 bp). Evidence from in vitro experiments demonstrates that these in vivo changes identified can abolish dimerization and reduce recombination frequency. Therefore, these results revealing differences in the DIS of discordant strains versus the similarity noted for the concordant strains may contribute to the differences in the frequency of recombination in patients superinfected with such HIV-1 variants. PMID:21453132

  1. Attitudes Towards PrEP and Anticipated Condom Use Among Concordant HIV-Negative and HIV-Discordant Male Couples

    PubMed Central

    Chakravarty, Deepalika; Bircher, Anja E.; Campbell, Chadwick K.; Grisham, Kirk; Neilands, Torsten B.; Wilson, Patrick A.; Dworkin, Shari

    2015-01-01

    Abstract Since the July 2012 approval by the FDA of emtricitabine/ tenofovir disoproxil fumarate (Truvada) for use as pre-exposure prophylaxis (PrEP) against HIV, its feasibility and acceptability has been under study. HIV-discordant couples are likely targets for PrEP but little is known about how this new prevention tool impacts relationships. We examined, among gay male couples, the acceptability of individual and partner use of PrEP and intentions to use condoms with primary and outside partners in the context of PrEP use. Data are from two independent samples of couples recruited in the San Francisco bay area and New York City—a qualitative one (N=48 couples) between March and November, 2011, and a quantitative one (N=171 couples) between June, 2012 and May, 2013. Data were categorized by couple HIV status and general linear models; chi-square tests of independence were used to examine condom-use intentions with primary and outside partners, by sexual risk profile, and race. Almost half of the HIV-negative couples felt PrEP was a good HIV prevention strategy for themselves and their partner. Over half reported that they would not change their current condom use if they or their partner were taking PrEP. However, approximately 30% of HIV-negative couples reported that they would stop using condoms or use them less with primary and outside partners if they were on PrEP or if their partner was on PrEP. A large percentage of couples view PrEP positively. However, to ensure safety for both partners, future programing must consider those who intend not to use condoms while on PrEP. PMID:26057304

  2. Attitudes Towards PrEP and Anticipated Condom Use Among Concordant HIV-Negative and HIV-Discordant Male Couples.

    PubMed

    Hoff, Colleen C; Chakravarty, Deepalika; Bircher, Anja E; Campbell, Chadwick K; Grisham, Kirk; Neilands, Torsten B; Wilson, Patrick A; Dworkin, Shari

    2015-07-01

    Since the July 2012 approval by the FDA of emtricitabine/ tenofovir disoproxil fumarate (Truvada) for use as pre-exposure prophylaxis (PrEP) against HIV, its feasibility and acceptability has been under study. HIV-discordant couples are likely targets for PrEP but little is known about how this new prevention tool impacts relationships. We examined, among gay male couples, the acceptability of individual and partner use of PrEP and intentions to use condoms with primary and outside partners in the context of PrEP use. Data are from two independent samples of couples recruited in the San Francisco bay area and New York City-a qualitative one (N=48 couples) between March and November, 2011, and a quantitative one (N=171 couples) between June, 2012 and May, 2013. Data were categorized by couple HIV status and general linear models; chi-square tests of independence were used to examine condom-use intentions with primary and outside partners, by sexual risk profile, and race. Almost half of the HIV-negative couples felt PrEP was a good HIV prevention strategy for themselves and their partner. Over half reported that they would not change their current condom use if they or their partner were taking PrEP. However, approximately 30% of HIV-negative couples reported that they would stop using condoms or use them less with primary and outside partners if they were on PrEP or if their partner was on PrEP. A large percentage of couples view PrEP positively. However, to ensure safety for both partners, future programing must consider those who intend not to use condoms while on PrEP. PMID:26057304

  3. Ethical Dilemma and Management of Infertility in HIV Seropositive Discordant Couples: A Case Study in Nigeria

    PubMed Central

    Umeora, OUJ; Chukwuneke, FN

    2013-01-01

    The traditional African society places an invaluable premium on procreation and, in some communities, a woman's place in her matrimony is only confirmed on positive reproductive outcome. Infertility is rife in Nigeria, and HIV/acquired immunodeficiency syndrome (AIDS) infection is a global pandemic, which has led to a drop in life expectancy across the world. In Nigeria, a number of cultural norms relating to gender roles and power dynamics constitute a serious barrier to issues of sexuality and infertility. Couples are concerned about their infertility diagnostic test being disclosed to each other, especially before marriage. This concern is understandable, especially in an environment that lacks the modern concepts and attitude toward sexual matters. This is complicated by the advent of HIV/AIDS infection and the societal mind-set that look at seropostive individuals as transgressors. At present, sexual and reproductive health rights are currently not in place because ethical issues are not given prominence by many physicians in Nigeria. A case of an infertile and seropostive discordant couple, which raised a lot of medical and ethical concerns, is presented here to awaken the consciousness of Nigerian physicians and stimulate discussions on the ethical matters such as this in clinical practice. PMID:23634339

  4. Community perceptions of childbearing and use of safer conception strategies among HIV-discordant couples in Kisumu, Kenya

    PubMed Central

    Breitnauer, Brooke T; Mmeje, Okeoma; Njoroge, Betty; Darbes, Lynae A; Leddy, Anna; Brown, Joelle

    2015-01-01

    Introduction Safer conception strategies (SCS) have the potential to decrease HIV transmission among HIV-discordant couples who desire children. Community perceptions of SCS may influence the scale-up and uptake of these services, but little is known about how communities will react to these strategies. Without community support for SCS, their success as an HIV prevention tool may be limited. The objective of this study is to characterize community perceptions of SCS for HIV-discordant couples in Kisumu, Kenya, to inform ongoing and future safer conception intervention studies in low-resource settings. Methods We conducted six focus group discussions and 11 in-depth-interviews in Kisumu, Kenya, among a diverse group (N=59) of community members, including men, women, youth (age 19–25), community health workers and local leaders. An iterative qualitative analysis using a grounded theory approach was employed. Results and discussion All participants emphasized the importance of childbearing in their society and the right to have children, regardless of an individual's HIV status. While most participants believed that HIV-discordant couples should be allowed to have children, they discussed several barriers to the uptake of SCS such as HIV-related stigma, fear of HIV transmission to the uninfected partner and child, fear of unfamiliar medical procedures and lack of information among community members and health care providers about HIV prevention interventions that allow safer conception. Access to information, community experiences with successful safer conception interventions, healthcare provider training, male engagement and community mobilization may help overcome these barriers. Though assisted reproduction strategies generated the most negative reactions from participants, our results suggest that with education and explanation of these services, participants express interest in these strategies and want them to be offered in their community. Conclusions Many

  5. Union faces trial for accusing employer of HIV safety lapses.

    PubMed

    1999-09-17

    The Service Employees International Union faces defamation charges after accusing Intercity Maintenance Co. of violating safety laws by not providing workers with gloves and other protection from HIV and hepatitis B. Intercity provides janitorial services for commercial buildings, including hospitals. During the heat of a campaign to organize its workers, the union made statements concerning safety violations which Intercity claimed interfered with the company's business relationship with a health-care insurer. The suit claims a violation of the Rhode Island Privacy Act because Intercity was placed in a false light. The judge found that the union's chief organizer, [name removed], may have acted with malice by accusing Intercity of violating State and Federal laws without proof. PMID:11366822

  6. “Maybe his blood is still strong”: a qualitative study among HIV-sero-discordant couples on ART in rural Uganda

    PubMed Central

    2012-01-01

    Background HIV-negative members of sero-discordant couples are at high risk for HIV acquisition but few behavioral prevention interventions have been implemented in sub-Saharan Africa and discordance is not well understood by couples themselves. Methods In this nested sub-study, we interviewed 40 HIV sero-discordant couples before and after a 6-month behavioral intervention that was comprised of four group discussions on specific HIV prevention and care topics. The content of the sessions included: 1) understanding HIV serodiscordance and reducing risk, 2) couple communication, 3) reproductive health and HIV serodiscordance, 4) coping with HIV serodiscordance and ongoing support. Couple members were interviewed individually. Data were analyzed thematically using ‘Framework Analysis’ which incorporated dyadic factors to address couple issues. Results Analysis revealed pre-identified concepts and emergent themes that were relevant to the final conceptual model. Four major categories of factors affecting couple relations, beliefs and current risk behaviors emerged: intervention factors, structural/contextual factors, physical health factors, and past risk behavior. The topics within the intervention most relevant were communication and reproductive health. The contextual factors highlighted by couples were gender norms around sexual decision-making and multiple partnerships. Individual beliefs regarding HIV serodiscordance persisted over all time points for some couples. Interestingly, some couple members had divergent views about their HIV status; some believing the HIV-negative member was negative while others described multiple beliefs around the negative member’s blood surely being positive for HIV. Couple communication emerged as an important theme mediating beliefs and behavior. Conclusions In addition to biomedical and behavioral interventions, HIV-serodiscordant couple interventions must embrace the contextual complexity and cultural understanding of HIV

  7. Discordance of HIV and HSV-2 Biomarkers and Self-reported Sexual Behavior among Orphan Adolescents in Western Kenya

    PubMed Central

    Cho, Hyunsan; Luseno, Winnie; Halpern, Carolyn; Zhang, Lei; Mbai, Isabella; Milimo, Benson; Hallfors, Denise

    2015-01-01

    Background This paper examines the discordance between biological data of HIV and HSV-2 infections and self-reported questionnaire responses among orphan adolescents in Western Kenya. Methods In 2011 a total of 837 orphan adolescents from 26 primary schools were enrolled in an HIV prevention trial. At baseline, blood samples were drawn for HIV and HSV-2 infection biomarker testing, and participants completed an audio computer-assisted self-interviewing (ACASI) survey. Results Comparing biological data with self-reported responses indicated that 70% of HIV positive (7 out of 10) and 64% of HSV-2 positive (18 out of 28 positive) participants reported never having had sex. Among ever-married adolescents 65% (57 out of 88) reported never having had sex. Overall, 10% of study participants appeared to have inconsistently reported their sexual behavior. Logistic regression analyses indicated that lower educational level and exam scores were significant predictors of inconsistent reporting. Conclusions Our study demonstrates the discordance between infections measured by biomarkers and self-reports of having had sex among orphan adolescents in Kenya. In order to detect program effects accurately in prevention research, it is necessary to collect both baseline and endline biological data. Furthermore, it is recommended to triangulate multiple data sources about adolescent participants’ self-reported information about marriage and pregnancies from school records and parent/guardians to verify the information. Researchers should recognize potential threats to validity in data and design surveys to consider cognitive factors and/or cultural context to obtain more accurate and reliable information from adolescents regarding HIV/STI risk behaviors. PMID:25378660

  8. Relationship and demographic factors associated with willingness to use an in-home HIV rapid test (HT) to screen potential sex partners among a US sample of HIV-negative and HIV-discordant male couples

    PubMed Central

    Mitchell, Jason W.; Sullivan, Patrick S.

    2015-01-01

    With dyadic data from a US Internet sample of 275 HIV-negative and 58 discordant male couples, we assessed HIV-negative partnered men's attitudes towards using an in-home rapid HIV test to screen potential new sex partners and associated factors by multivariate multilevel modeling. HIV-negative partnered men were “likely” to use a HT for screening purposes. More positive attitudes were associated with being in a mixed/nonwhite relationship; having an open sexual agreement. Less positive attitudes were associated with both partners being well educated. These findings may highlight how to make the most of HTs as risk-reduction screening tool among at-risk male couples. PMID:26009834

  9. Brief Report: Relationship and Demographic Factors Associated With Willingness to Use an In-Home Rapid HIV Test to Screen Potential Sex Partners Among a US Sample of HIV-Negative and HIV-Discordant Male Couples.

    PubMed

    Mitchell, Jason W; Sullivan, Patrick S

    2015-06-01

    With dyadic data from a US Internet sample of 275 HIV-negative and 58 discordant male couples, we assessed HIV-negative partnered men's attitudes toward using an in-home rapid HIV test (HT) to screen potential new sex partners and associated factors by multivariate multilevel modeling. HIV-negative partnered men were "likely" to use an HT for screening purposes. More positive attitudes were associated with being in a mixed/nonwhite relationship; having an open sexual agreement. Less positive attitudes were associated with both partners being well educated. These findings may highlight how to make the most of HTs as risk-reduction screening tool among at-risk male couples. PMID:26009834

  10. Relationship characteristics differ based on use of substances with sex among an urban internet sample of HIV-discordant and HIV-positive male couples.

    PubMed

    Mitchell, Jason W

    2015-02-01

    Previous research with men who have sex with men (MSM) has found that substance use with sex is strongly associated with HIV acquisition and poor adherence to HIV treatments. Although some studies have assessed male couples' use of substances with unprotected anal sex, little is known on whether differences in their relationship dynamics are associated with their usage. Current HIV prevention initiatives underscore the importance of studying male couples' relationship dynamics. Using dyadic data from 28 HIV-positive and 58 HIV-discordant male couples, this analysis sought to: (1) describe, by substance type, whether neither, one, or both partners in the couple used a particular substance with sex within their relationship or outside of the relationship, respectively, and (2) assess, by substance type, whether relationship characteristic differences existed between these three groups of couples with respect to substance use with sex within and outside the relationship. Data from 86 dyads came from a cross-sectional, Internet study. Multivariate multinomial regression models were employed to achieve the aims. Except for alcohol, most did not use substances with sex. Within the relationship, those who used with sex varied by substance type; outside the relationship, most couples had only one partner who used with sex regardless of substance type. Several relationship characteristic differences were noted between the groups of couples. Within the relationship, marijuana and erectile dysfunction medication (EDM) use with sex was associated with having less tangible resources; for outside the relationship, these were associated with perceiving to have greater quality of alternatives. In general, amyl nitrates and party drug use with sex were associated with viewing the main partner as being less dependable for trustworthiness. Marijuana and party drug use with sex within the relationship and EDM use with sex outside the relationship were negatively associated with being

  11. Dyadic Effects of Stigma and Discrimination on Distress in Chinese HIV Discordant Couples.

    PubMed

    Yu, Nancy Xiaonan; Chan, Cecilia L W; Zhang, Jianxin

    2016-08-01

    The present study investigated the dyadic effects of stigma and discrimination on distress in Chinese couples affected by HIV. Chinese people living with HIV (PLHIV) and their seronegative spouses (N = 119 couples) participated in this study. The PLHIV completed measures on stigma beliefs about being better off dead and dignity-related distress. The spouses completed measures on perceived discrimination and exclusion and caregiver distress. The results showed that there was no significant correlation between the PLHIV's stigma beliefs and the spouses' perceived discrimination and exclusion. The couples showed significant associations in their dignity-related distress and caregiver distress. Analyses using the actor-partner interdependence model showed that PLHIV's stigma beliefs and the spouses' perceived discrimination and exclusion both had significant actor and partner effects on distress within the dyad. Psychosocial interventions aiming for distress reduction in the context of HIV should tackle stigma and discrimination and target the couples rather than solely the patient or spouse. PMID:27427923

  12. Risk Reduction Among HIV-Seroconcordant and -Discordant Couples: The Zambia NOW2 Intervention

    PubMed Central

    Kashy, Deborah; Chitalu, Ndashi; Kankasa, Chipepo; Mumbi, Mirriam; Cook, Ryan; Weiss, Stephen

    2014-01-01

    Abstract Heterosexual HIV transmission remains the leading cause of HIV incidence in adult men and women in sub-Saharan Africa. This study assessed whether an HIV risk-reduction intervention would be more likely to increase sexual barrier acceptability and decrease risk behavior when delivered to couples in gender concordant groups or in an individual format. This study also examined the mutual impact of couple members as a source of influence on acceptability, and assessed whether product acceptability, intimate partner violence (IPV), and/or partner communication predicted sexual barrier use. HIV seroconcordant and serodiscordant couples (n=216) were recruited in Lusaka, Zambia, and randomized to a four session gender-concordant intervention. Participants were assessed at baseline, 6, and 12 months. Willingness to use barriers (p=0.012), acceptability (p<0.001), and barrier use (p<0.001) increased over time in both conditions, and were influenced by gender preferences. IPV decreased (p=0.040) and positive communication increased (p<0.001) in both conditions. Individual and gender concordant group sessions achieved similar increases in sexual barrier use following the intervention. Results highlight the influence of partners as well as product acceptability as predictors of sexual barrier use among couples in sub-Saharan Africa. Future prevention studies should consider both product acceptability and partner influence to achieve optimal sexual risk behavior outcomes. PMID:24983201

  13. Human leukocyte antigen B distribution in HIV discordant cohort from India.

    PubMed

    Chaudhari, Deepali V; Chavan, Vijay R; Ahir, Swati P; Kerkar, Shilpa C; Mehta, Preeti R; Mania-Pramanik, Jayanti

    2013-01-01

    Limited reports are available on association of HLA-B with HIV infection from India, a home to the third largest population of HIV infected people in the world. This emphasizes the need to have more information specifically the genetic constitution of HIV serodiscordant couples (DCs), where one spouse is seropositive (HSP) while the other remains seronegative (HSN) even after repeated exposure. Hence, aim of this study was to document association of HLA-B with HIV infection in DCs living in Mumbai, India. A cohort was designed to enroll DCs attending the ICTC/Shakti Clinic of KEM Hospital, Mumbai. A group of unexposed volunteers were also enrolled as healthy controls (HC). HLA-B alleles were typed using sequence-specific oligonucleotide probes. Allele frequency comparison was done using 2×2 contingency tables. Results were considered significant, when p<0.05 with two-tailed Fisher's exact test. At HLA-B locus, the frequencies of HLA-B*40;-B*35;-B*07;-B*15;-B*51;-B*44;-B*52;-B*37 and -B*57 were found in decreasing order in the population. Frequency of HLA-B*35 allele was significantly higher (HSP vs HSN; p<0.02 and HSP vs HC; p<0.04) in HSP. HLA-B*40 (HSN vs HSP; p<0.01 and HC vs HSP; p<0.01) and HLA-B*18 (HSN vs HSP; p<0.02) were significantly associated with HSN. Both HSN and HC had similar HLA-B*35 and -B*40 allele frequency. HLA-B*57 allele was observed in 15 individuals (3.69%). However, HLA-B*57:01 which is known to be associated with adverse reactions against Abacavir was observed in 7 of them. HLA-B*39 was observed exclusively in HSP. Our observation in DCs confirmed the association of HLA-B*35 with susceptibility while HLA-B*40 (specifically *B40:06), -B*18 with protection. These identified alleles can be used as possible marker associated with HIV transmission. In India, HLA screening is not carried out before initiation of HIV treatment. However, the presence of HLA-B*57:01 in the population emphasizes the importance of such screening to predict

  14. HIV-Negative Partnered Men's Willingness to Use Pre-Exposure Prophylaxis and Associated Factors Among an Internet Sample of U.S. HIV-Negative and HIV-Discordant Male Couples

    PubMed Central

    Stephenson, Rob

    2015-01-01

    Abstract Purpose: Research on male couples' willingness to use pre-exposure prophylaxis (PrEP) is critically lacking. Methods: A cross-sectional 2011 Internet survey collected dyadic data from 275 HIV-negative and 58 HIV-discordant male couples to describe 631 HIV-negative partnered mens' willingness to use PrEP and associated couple-level demographic and behavioral factors with multivariate multilevel modeling. Results: Fifty-three percent were very to extremely likely to use PrEP. Willingness was positively associated with being in a mixed race and behaviorally non-monogamous relationship, and with amyl nitrate use with sex outside the relationship. Willingness was negatively associated with having a college education. Conclusion: Prevention efforts should educate male couples about the potential benefits of PrEP. PMID:26790016

  15. Discordant Immune Response with Antiretroviral Therapy in HIV-1: A Systematic Review of Clinical Outcomes

    PubMed Central

    Kelly, Christine; Gaskell, Katherine M.; Richardson, Marty; Klein, Nigel; Garner, Paul; MacPherson, Peter

    2016-01-01

    Background A discordant immune response (DIR) is a failure to satisfactorily increase CD4 counts on ART despite successful virological control. Literature on the clinical effects of DIR has not been systematically evaluated. We aimed to summarise the risk of mortality, AIDS and serious non-AIDS events associated with DIR with a systematic review. Methods The protocol is registered with the Centre for Review Dissemination, University of York (registration number CRD42014010821). Included studies investigated the effect of DIR on mortality, AIDS, or serious non-AIDS events in cohort studies or cohorts contained in arms of randomised controlled trials for adults aged 16 years or older. DIR was classified as a suboptimal CD4 count (as defined by the study) despite virological suppression following at least 6 months of ART. We systematically searched PubMed, Embase, and the Cochrane Library to December 2015. Risk of bias was assessed using the Cochrane tool for assessing risk of bias in cohort studies. Two authors applied inclusion criteria and one author extracted data. Risk ratios were calculated for each clinical outcome reported. Results Of 20 studies that met the inclusion criteria, 14 different definitions of DIR were used. Risk ratios for mortality in patients with and without DIR ranged between 1.00 (95% CI 0.26 to 3.92) and 4.29 (95% CI 1.96 to 9.38) with the majority of studies reporting a 2 to 3 fold increase in risk. Conclusions DIR is associated with a marked increase in mortality in most studies but definitions vary widely. We propose a standardised definition to aid the development of management options for DIR. PMID:27284683

  16. HIV research productivity and structural factors associated with HIV research output in European Union countries: a bibliometric analysis

    PubMed Central

    Uusküla, A; Toompere, K; Laisaar, K T; Rosenthal, M; Pürjer, M L; Knellwolf, A; Läärä, E; Des Jarlais, D C

    2015-01-01

    Objectives To assess HIV/AIDS research productivity in the 27 countries of the European Union (EU), and the structural level factors associated with levels of HIV/AIDS research productivity. Methods A bibliometric analysis was conducted with systematic search methods used to locate HIV/AIDS research publications (period of 1 January 2002 to 31 December 2011; search databases: MEDLINE (Ovid, PubMed), EMBASE, ISI-Thomson Web of Science; no language restrictions). The publication rate (number of HIV/AIDS research publications per million population in 10 years) and the rate of articles published in HIV/AIDS journals and selected journals with moderate to very high (IF ≥3) 5-year impact factors were used as markers for HIV research productivity. A negative binomial regression model was fitted to assess the impact of structural level factors (sociodemographic, health, HIV prevalence and research/development indicators) associated with the variation in HIV research productivity. Results The total numbers of HIV/AIDS research publications in 2002–2011 by country ranged from 7 to 9128 (median 319). The median publication rate (per million population in 10 years) was 45 (range 5–150) for all publications. Across all countries, 16% of the HIV/AIDS research was published in HIV/AIDS journals and 7% in selected journals with IF ≥3. Indicators describing economic (gross domestic product), demographic (size of the population) and epidemiological (HIV prevalence) conditions as well as overall scientific activity (total research output) in a country were positively associated with HIV research productivity. Conclusions HIV research productivity varies noticeably across EU countries, and this variation is associated with recognisable structural factors. PMID:25649212

  17. HIV-Negative Partnered Men's Willingness to Use Non-Occupational Post-Exposure Prophylaxis and Associated Factors in a U.S. Sample of HIV-Negative and HIV-Discordant Male Couples

    PubMed Central

    Sophus, Amber I.; Petroll, Andrew E.

    2016-01-01

    Abstract Purpose: Non-occupational post-exposure prophylaxis (nPEP) is an underutilized biomedical option for HIV prevention. Few studies have assessed male couples' knowledge of and willingness to use nPEP. Methods: Cross-sectional dyadic data from 275 HIV-negative and 58 HIV-discordant male couples were used to describe HIV-negative, partnered men's awareness of and willingness to use nPEP, and factors associated with their willingness to use nPEP. Data were analyzed with the use of multivariate multilevel modeling. Results: Less than a third of the men were aware of nPEP, yet 73% were very-to-extremely likely to use nPEP. Partnered men's willingness to use nPEP was positively associated with having an individual income less than $30,000 USD and serosorting within the relationship. Willingness to use nPEP was negatively associated with greater age difference between primary partners and with higher scores on measures of couples' investment in their relationship. Conclusion: Efforts should be made to increase male couples' awareness of nPEP and how to access nPEP. Uptake of nPEP has the potential to help avert new HIV infections among male couples. PMID:26789400

  18. Discordant Impact of HLA on Viral Replicative Capacity and Disease Progression in Pediatric and Adult HIV Infection.

    PubMed

    Adland, Emily; Paioni, Paolo; Thobakgale, Christina; Laker, Leana; Mori, Luisa; Muenchhoff, Maximilian; Csala, Anna; Clapson, Margaret; Flynn, Jacquie; Novelli, Vas; Hurst, Jacob; Naidoo, Vanessa; Shapiro, Roger; Huang, Kuan-Hsiang Gary; Frater, John; Prendergast, Andrew; Prado, Julia G; Ndung'u, Thumbi; Walker, Bruce D; Carrington, Mary; Jooste, Pieter; Goulder, Philip J R

    2015-06-01

    HLA class I polymorphism has a major influence on adult HIV disease progression. An important mechanism mediating this effect is the impact on viral replicative capacity (VRC) of the escape mutations selected in response to HLA-restricted CD8+ T-cell responses. Factors that contribute to slow progression in pediatric HIV infection are less well understood. We here investigate the relationship between VRC and disease progression in pediatric infection, and the effect of HLA on VRC and on disease outcome in adult and pediatric infection. Studying a South African cohort of >350 ART-naïve, HIV-infected children and their mothers, we first observed that pediatric disease progression is significantly correlated with VRC. As expected, VRCs in mother-child pairs were strongly correlated (p = 0.004). The impact of the protective HLA alleles, HLA-B*57, HLA-B*58:01 and HLA-B*81:01, resulted in significantly lower VRCs in adults (p<0.0001), but not in children. Similarly, in adults, but not in children, VRCs were significantly higher in subjects expressing the disease-susceptible alleles HLA-B*18:01/45:01/58:02 (p = 0.007). Irrespective of the subject, VRCs were strongly correlated with the number of Gag CD8+ T-cell escape mutants driven by HLA-B*57/58:01/81:01 present in each virus (p = 0.0002). In contrast to the impact of VRC common to progression in adults and children, the HLA effects on disease outcome, that are substantial in adults, are small and statistically insignificant in infected children. These data further highlight the important role that VRC plays both in adult and pediatric progression, and demonstrate that HLA-independent factors, yet to be fully defined, are predominantly responsible for pediatric non-progression. PMID:26076345

  19. Discordant Impact of HLA on Viral Replicative Capacity and Disease Progression in Pediatric and Adult HIV Infection

    PubMed Central

    Adland, Emily; Paioni, Paolo; Thobakgale, Christina; Laker, Leana; Mori, Luisa; Muenchhoff, Maximilian; Csala, Anna; Clapson, Margaret; Flynn, Jacquie; Novelli, Vas; Hurst, Jacob; Naidoo, Vanessa; Shapiro, Roger; Huang, Kuan-Hsiang Gary; Frater, John; Prendergast, Andrew; Prado, Julia G.; Ndung’u, Thumbi; Walker, Bruce D.; Carrington, Mary; Jooste, Pieter; Goulder, Philip J. R.

    2015-01-01

    HLA class I polymorphism has a major influence on adult HIV disease progression. An important mechanism mediating this effect is the impact on viral replicative capacity (VRC) of the escape mutations selected in response to HLA-restricted CD8+ T-cell responses. Factors that contribute to slow progression in pediatric HIV infection are less well understood. We here investigate the relationship between VRC and disease progression in pediatric infection, and the effect of HLA on VRC and on disease outcome in adult and pediatric infection. Studying a South African cohort of >350 ART-naïve, HIV-infected children and their mothers, we first observed that pediatric disease progression is significantly correlated with VRC. As expected, VRCs in mother-child pairs were strongly correlated (p = 0.004). The impact of the protective HLA alleles, HLA-B*57, HLA-B*58:01 and HLA-B*81:01, resulted in significantly lower VRCs in adults (p<0.0001), but not in children. Similarly, in adults, but not in children, VRCs were significantly higher in subjects expressing the disease-susceptible alleles HLA-B*18:01/45:01/58:02 (p = 0.007). Irrespective of the subject, VRCs were strongly correlated with the number of Gag CD8+ T-cell escape mutants driven by HLA-B*57/58:01/81:01 present in each virus (p = 0.0002). In contrast to the impact of VRC common to progression in adults and children, the HLA effects on disease outcome, that are substantial in adults, are small and statistically insignificant in infected children. These data further highlight the important role that VRC plays both in adult and pediatric progression, and demonstrate that HLA-independent factors, yet to be fully defined, are predominantly responsible for pediatric non-progression. PMID:26076345

  20. "Getting tested is almost like going to the Salem witch trials": discordant discourses between Western public health messages and sociocultural expectations surrounding HIV testing among East African immigrant women.

    PubMed

    De Jesus, Maria; Carrete, Claudia; Maine, Cathleen; Nalls, Patricia

    2015-01-01

    Washington, DC, has the highest AIDS diagnosis rate in the USA, and Black women are disproportionately affected. Although HIV testing is the first entryway into vital treatment services, evidence reveals that foreign-born blacks have a lower rate of recent HIV testing than US-born blacks. To date, however, there are no studies that examine the culture-specific perceptions of HIV testing among East African immigrant women (who comprise a large share of Black Africans in DC) to better understand their potential barriers to testing. Adopting the PEN-3 cultural model as our theoretical framework, the main objective of this study was to examine East African women's HIV testing perceptions and partner communication norms. Between October 2012 and March 2013, trained interviewers conducted a total of 25 interviews with East African women in the Washington, DC, metropolitan area. For triangulation purposes, data collection consisted of both in-depth, semi-structured interviews and cognitive interviews, in which participants were administered a quantitative survey and assessed on how they interpreted items. Qualitative thematic analysis revealed a systematic pattern of discordant responses across participants. While they were aware of messages related to Western public health discourse surrounding HIV testing (e.g., Everyone should get tested for HIV; One should talk to one's spouse about HIV testing), divergent sociocultural expectations rooted in cultural and religious beliefs prevailed (e.g., Getting an HIV test brings shame to the person who got tested and to one's family; it implies one is engaging in immoral behavior; One should not talk with one's spouse about HIV testing; doing so breaks cultural norms). Implications of using a culture-centered model to examine the role of sociocultural expectations in HIV prevention research and to develop culturally responsive prevention strategies are discussed. PMID:25616443

  1. ‘Getting tested is almost like going to the Salem witch trials’: Discordant discourses between western public health messages and sociocultural expectations surrounding HIV testing among East African immigrant women

    PubMed Central

    DE JESUS, Maria; CARRETE, Claudia; MAINE, Cathleen; NALLS, Patricia

    2015-01-01

    Washington, DC has the highest AIDS diagnosis rate in the United States and Black women are disproportionately affected. Although HIV testing is the first entryway into vital treatment services, evidence reveals that foreign-born blacks have a lower rate of recent HIV testing than U.S.-born blacks. To date, however, there are no studies that examine the culture-specific perceptions of HIV testing among East African immigrant women (who comprise a large share of Black Africans in DC) to better understand their potential barriers to testing. Adopting the PEN-3 cultural model as our theoretical framework, the main objective of this study was to examine East African women’s HIV testing perceptions and partner communication norms. Between October 2012 and March 2013, trained interviewers conducted a total of 25 interviews with East African women in the Washington DC Metropolitan area. For triangulation purposes, data collection consisted of both in-depth, semi-structured interviews and cognitive interviews, in which participants were administered a quantitative survey and assessed on how they interpreted items. Qualitative thematic analysis revealed a systematic pattern of discordant responses across participants. While they were aware of messages related to western public health discourse surrounding HIV testing (e.g., Everyone should get tested for HIV; One should talk to one’s spouse about HIV testing), divergent sociocultural expectations rooted in cultural and religious beliefs prevailed (e.g., Getting an HIV test brings shame to the person who got tested and to one’s family; it implies one is engaging in immoral behavior; One should not talk with one’s spouse about HIV testing; doing so breaks cultural norms). Implications of using a culture-centered model to examine the role of sociocultural expectations in HIV prevention research and to develop culturally responsive prevention strategies are discussed. PMID:25616443

  2. Discordance at human leukocyte antigen-DRB3 and protection from human immunodeficiency virus type 1 transmission.

    PubMed

    Hader, Shannon L; Hodge, Thomas W; Buchacz, Kate A; Bray, Robert A; Padian, Nancy S; Rausa, Alfio; Slaviniski, Sally A; Holmberg, Scott D

    2002-06-15

    Host human leukocyte antigens (HLAs) integrated into the human immunodeficiency virus (HIV) type 1 envelope could theoretically determine, as in tissue transplants, whether HIV-1 is "rejected" by exposed susceptible persons, preventing transmission. HLA discordance (mismatch) was examined among 45 heterosexual partner pairs in which at least 1 partner was HIV-1 infected and exposure or transmission between partners had occurred. Immunologic discordance at class II HLA-DRB3 (present in the HIV donor partner but absent in the recipient partner) was associated with lack of transmission of HIV-1. Eight (35%) of 23 partner pairs in which HIV-1 transmission did not occur were immunologically discordant at HLA-DRB3, compared with 0 of 11 partner pairs in which HIV-1 transmission did occur (P=.027). Further investigation of the roles of class II HLAs in HIV-1 transmission and as possible components of HIV-1 vaccines should be pursued. PMID:12085318

  3. Discordant responses to cART in HIV-1 patients in the era of high potency antiretroviral drugs: clinical evaluation, classification, management prospects.

    PubMed

    Cenderello, Giovanni; De Maria, Andrea

    2016-01-01

    The goal of antiretroviral treatment (ART) in HIV-1 patients is immune reconstitution following control of viral replication. CD4+ cell number/proportions are a crude but essential correlate of immune reconstitution. Despite suppression of HIV replication, a fraction of ART-treated patients still fails to fully reconstitute CD4+ T cell numbers (immunological nonresponders, INRs). New drugs, regimens and treatment strategies led to increased efficacy, lower side effects and higher virological success rates in clinical practice. The multitude of described immune defects and clinical events accompanying INR opposed to the marginal effect of antiretroviral intensification or immunotherapy trials underline the need for continuing efforts at understanding the mechanisms that underlie INR. Here, we reassess INR definition, frequency, and the achievements of active clinical and translational research suggesting a shared definition for insufficient, partial and complete CD4+ cell number recovery thus improving homogeneity in patient selection and mechanism identification. PMID:26513236

  4. On the European Union's new eastern border: health promotion, HIV and Ukraine.

    PubMed

    Neil, Lindsay; Zalata, Oleg; Coker, Richard

    2005-08-01

    HIV control in Ukraine is a pressing public health challenge and national efforts to control the epidemic have been hindered by a lack of capacity and resources. One component of control is the need to raise awareness. Implementing a health promotion strategy through the education system and through multi-sector network with early stakeholder ownership resulted in a limited budget being spent principally on production costs rather than purchasing media time and space with considerable savings. Early involvement of powerful corporate stakeholders in multi-disciplinary teams has the potential to enhance the effectiveness and efficiency of health promotion measures in a post-Soviet transitional economy. PMID:15979985

  5. Purified discord and multipartite entanglement

    SciTech Connect

    Brown, Eric G.; Webster, Eric J.; Martín-Martínez, Eduardo; Kempf, Achim

    2013-10-15

    We study bipartite quantum discord as a manifestation of a multipartite entanglement structure in the tripartite purified system. In particular, we find that bipartite quantum discord requires the presence of both bipartite and tripartite entanglement in the purification. This allows one to understand the asymmetry of quantum discord, D(A,B)≠D(B,A) in terms of entanglement monogamy. As instructive special cases, we study discord for qubits and Gaussian states in detail. As a result of this we shed new light on a counterintuitive property of Gaussian states: the presence of classical correlations necessarily requires the presence of quantum correlations. Finally, our results also shed new light on a protocol for remote activation of entanglement by a third party. -- Highlights: •Bipartite quantum discord as a manifestation of multipartite entanglement. •Relevance of quantum discord as a utilizable resource for quantum info. tasks. •Quantum discord manifests itself in entanglement in the purified state. •Relation between asymmetry of discord and entanglement monogamy. •Protocol for remote activation of entanglement by a third party.

  6. Quantum discord with weak measurements

    SciTech Connect

    Singh, Uttam Pati, Arun Kumar

    2014-04-15

    Weak measurements cause small change to quantum states, thereby opening up the possibility of new ways of manipulating and controlling quantum systems. We ask, can weak measurements reveal more quantum correlation in a composite quantum state? We prove that the weak measurement induced quantum discord, called as the “super quantum discord”, is always larger than the quantum discord captured by the strong measurement. Moreover, we prove the monotonicity of the super quantum discord as a function of the measurement strength and in the limit of strong projective measurement the super quantum discord becomes the normal quantum discord. We find that unlike the normal discord, for pure entangled states, the super quantum discord can exceed the quantum entanglement. Our results provide new insights on the nature of quantum correlation and suggest that the notion of quantum correlation is not only observer dependent but also depends on how weakly one perturbs the composite system. We illustrate the key results for pure as well as mixed entangled states. -- Highlights: •Introduced the role of weak measurements in quantifying quantum correlation. •We have introduced the notion of the super quantum discord (SQD). •For pure entangled state, we show that the SQD exceeds the entanglement entropy. •This shows that quantum correlation depends not only on observer but also on measurement strength.

  7. Quantum discord and Maxwell's demons

    SciTech Connect

    Zurek, Wojciech Hubert

    2003-01-01

    Quantum discord was proposed as an information-theoretic measure of the 'quantumness' of correlations. I show that discord determines the difference between the efficiency of quantum and classical Maxwell's demons - that is, entities that can or cannot measure nonlocal observables or carry out conditional quantum operations - in extracting work from collections of correlated quantum systems.

  8. Risks worth Taking: Safety Agreements among Discordant Gay Couples

    PubMed Central

    Beougher, Sean C.; Chakravarty, Deepalika; Garcia, Carla C.; Darbes, Lynae A.; Neilands, Torsten B.; Hoff, Colleen C.

    2012-01-01

    As HIV research and prevention efforts increasingly target gay men in relationships, situational factors such as couple serostatus and agreements about sex become central to examinations of risk. Discordant gay couples are of particular interest because the risk of HIV infection is seemingly near-at-hand. Yet little is known about their sexual behaviors, agreements about sex, and safer sex efforts. The present study utilized longitudinal semi-structured, qualitative interviews to explore these issues among 12 discordant couples. Findings show that nearly every couple had agreements about reducing the likelihood of HIV transmission from one partner to the other. Negotiating these agreements involved establishing a level of acceptable risk, determining condom use, and employing other risk-reduction techniques, such as seropositioning and withdrawal. For half of the couples, these agreements did not involve using condoms; only two couples reported consistent condom use. Despite forgoing condoms, however, none reported seroconversion over the course of data collection. Additional issues are raised where long-term HIV prevention is concerned. Future prevention efforts with discordant couples should work with, rather than fight against, the couple’s decision to use condoms and endeavor to complement and accentuate their other safer sex efforts. PMID:22292838

  9. Discordant Treatment Responses to Combination Antiretroviral Therapy in Rwanda: A Prospective Cohort Study

    PubMed Central

    Kayigamba, Felix R.; Franke, Molly F.; Bakker, Mirjam I.; Rodriguez, Carly A.; Bagiruwigize, Emmanuel; Wit, Ferdinand WNM; Rich, Michael L.; Schim van der Loeff, Maarten F.

    2016-01-01

    Introduction Some antiretroviral therapy naïve patients starting combination antiretroviral therapy (cART) experience a limited CD4 count rise despite virological suppression, or vice versa. We assessed the prevalence and determinants of discordant treatment responses in a Rwandan cohort. Methods A discordant immunological cART response was defined as an increase of <100 CD4 cells/mm3 at 12 months compared to baseline despite virological suppression (viral load [VL] <40 copies/mL). A discordant virological cART response was defined as detectable VL at 12 months with an increase in CD4 count ≥100 cells/mm3. The prevalence of, and independent predictors for these two types of discordant responses were analysed in two cohorts nested in a 12-month prospective study of cART-naïve HIV patients treated at nine rural health facilities in two regions in Rwanda. Results Among 382 patients with an undetectable VL at 12 months, 112 (29%) had a CD4 rise of <100 cells/mm3. Age ≥35 years and longer travel to the clinic were independent determinants of an immunological discordant response, but sex, baseline CD4 count, body mass index and WHO HIV clinical stage were not. Among 326 patients with a CD4 rise of ≥100 cells/mm3, 56 (17%) had a detectable viral load at 12 months. Male sex was associated with a virological discordant treatment response (P = 0.05), but age, baseline CD4 count, BMI, WHO HIV clinical stage, and travel time to the clinic were not. Conclusions Discordant treatment responses were common in cART-naïve HIV patients in Rwanda. Small CD4 increases could be misinterpreted as a (virological) treatment failure and lead to unnecessary treatment changes. PMID:27438000

  10. Quantum discord, local operations, and Maxwell's demons

    SciTech Connect

    Brodutch, Aharon; Terno, Daniel R.

    2010-06-15

    Quantum discord was proposed as a measure of the quantumness of correlations. There are at least three different discordlike quantities, two of which determine the difference between the efficiencies of a Szilard's engine under different sets of restrictions. The three discord measures vanish simultaneously. We introduce an easy way to test for zero discord, relate it to the Cerf-Adami conditional entropy and show that there is no simple relation between the discord and the local distinguishability.

  11. Non-Markovian dynamics of quantum discord

    SciTech Connect

    Fanchini, F. F.; Caldeira, A. O.; Werlang, T.; Brasil, C. A.; Arruda, L. G. E.

    2010-05-15

    We evaluate the quantum discord dynamics of two qubits in independent and common non-Markovian environments. We compare the dynamics of entanglement with that of quantum discord. For independent reservoirs the quantum discord vanishes only at discrete instants whereas the entanglement can disappear during a finite time interval. For a common reservoir, quantum discord and entanglement can behave very differently with sudden birth of the former but not of the latter. Furthermore, in this case the quantum discord dynamics presents sudden changes in the derivative of its time evolution which is evidenced by the presence of kinks in its behavior at discrete instants of time.

  12. Observing the operational significance of discord consumption

    NASA Astrophysics Data System (ADS)

    Gu, Mile; Chrzanowski, Helen M.; Assad, Syed M.; Symul, Thomas; Modi, Kavan; Ralph, Timothy C.; Vedral, Vlatko; Lam, Ping Koy

    2012-09-01

    Coherent interactions that generate negligible entanglement can still exhibit unique quantum behaviour. This observation has motivated a search beyond entanglement for a complete description of all quantum correlations. Quantum discord is a promising candidate. Here, we demonstrate that under certain measurement constraints, discord between bipartite systems can be consumed to encode information that can only be accessed by coherent quantum interactions. The inability to access this information by any other means allows us to use discord to directly quantify this `quantum advantage'. We experimentally encode information within the discordant correlations of two separable Gaussian states. The amount of extra information recovered by coherent interaction is quantified and directly linked with the discord consumed during encoding. No entanglement exists at any point of this experiment. Thus we introduce and demonstrate an operational method to use discord as a physical resource.

  13. Non-commutativity measure of quantum discord

    PubMed Central

    Guo, Yu

    2016-01-01

    Quantum discord is a manifestation of quantum correlations due to non-commutativity rather than entanglement. Two measures of quantum discord by the amount of non-commutativity via the trace norm and the Hilbert-Schmidt norm respectively are proposed in this paper. These two measures can be calculated easily for any state with arbitrary dimension. It is shown by several examples that these measures can reflect the amount of the original quantum discord. PMID:27122226

  14. Non-commutativity measure of quantum discord.

    PubMed

    Guo, Yu

    2016-01-01

    Quantum discord is a manifestation of quantum correlations due to non-commutativity rather than entanglement. Two measures of quantum discord by the amount of non-commutativity via the trace norm and the Hilbert-Schmidt norm respectively are proposed in this paper. These two measures can be calculated easily for any state with arbitrary dimension. It is shown by several examples that these measures can reflect the amount of the original quantum discord. PMID:27122226

  15. Geometric quantum discord under noisy environment

    NASA Astrophysics Data System (ADS)

    Huang, Zhiming; Qiu, Daowen

    2016-05-01

    In this work, we mainly analyze the dynamics of geometric quantum discord under a common dissipating environment. Our results indicate that geometric quantum discord is generated when the initial state is a product state. The geometric quantum discord increases from zero to a stable value with the increasing time, and the variations of stable values depend on the system size. For different initial product states, geometric quantum discord has some different behaviors in contrast with entanglement. For initial maximally entangled state, it is shown that geometric quantum discord decays with the increasing dissipated time. It is found that for EPR state, entanglement is more robust than geometric quantum discord, which is a sharp contrast to the existing result that quantum discord is more robust than entanglement in noisy environments. However, for GHZ state and W state, geometric quantum discord is more stable than entanglement. By the comparison of quantum discord and entanglement, we find that a common dissipating environment brings complicated effects on quantum correlation, which may deepen our understanding of physical impacts of decohering environment on quantum correlation. In the end, we analyze the effects of collective dephasing noise and rotating noise to a class of two-qubit X states, and we find that quantum correlation is not altered by the collective noises.

  16. Cost and safety of assisted reproductive technologies for human immunodeficiency virus-1 discordant couples.

    PubMed

    Wu, Ming-Yih; Ho, Hong-Nerng

    2015-05-12

    Due to significant advances in the treatment of human immunodeficiency virus type-1 (HIV-1), HIV-1 infection gradually has become a treatable chronic disease. Successfully treated HIV-positive individuals can have a normal life expectancy. Hence, more and more HIV-1 discordant couples in Taiwan and the rest of the world are seeking fertility assistance. Pre-treatment of highly active antiretroviral therapy (HAART) combined with sperm washing and RT-polymerase chain reaction examination for HIV-1 viral load has become the standard procedure to assist them to conceive. However, in order to reduce the transmission risk to the lowest level for the couple and to diminish the cost of health care for the insurance institutes or government, in vitro fertilization (IVF)-intracytoplasmic sperm injection (ICSI) therapy provides the ideal solution for HIV-1 discordant couples with infected men. Intrauterine insemination (IUI) theoretically introduces more than 10(7) times of sperm counts or semen volume to uninfected women vs IVF-ICSI. However, since some regimens of HAART may significantly decrease the sperm motility, compared to IVF-ICSI, IUI only produces 1/5 to 1/2 pregnancy rates per cycle. Given the risk of seroconversion of HIV infection which actually happens after successful treatment, IVF-ICSI for these HIV-1 seropositive men is more cost-effective and should be the first line treatment for these cases. PMID:25964879

  17. HIV

    PubMed Central

    Chawla, Sumit; Sahoo, Soumya Swaroop; Jain, Rambilas; Khanna, Pardeep; Mehta, Bharti; Singh, Inderjeet

    2014-01-01

    Getting to zero: zero new HIV infections, zero deaths from AIDS-related illness, zero discrimination is the theme of World AIDS Day 2012. Given the spread of the epidemic today, getting to zero may sound difficult, but significant progress is underway. The total annual loss for the entire country due to HIV is 7% of GDP, which exceeds India’s annual health expenditure in 2004. The additional loss due to loss of labor income and increased medical expenditure as measured by the external transfers, account for 5% of the country’s health expenditure and 0.23% of GDP. Given that the HIV incidence rate is only 0.27% in India, these losses are quite staggering. Despite the remarkable achievements in development of anti-retroviral therapies against HIV and the recent advances in new prevention technologies, the rate of new HIV infections continue to outpace efforts on HIV prevention and control. Thus, the development of a safe and effective vaccine for prevention and control of AIDS remains a global public health priority and the greatest opportunity to eventually end the AIDS pandemic. PMID:24056755

  18. 'It's risky to walk in the city with syringes': understanding access to HIV/AIDS services for injecting drug users in the former Soviet Union countries of Ukraine and Kyrgyzstan

    PubMed Central

    2011-01-01

    Background Despite massive scale up of funds from global health initiatives including the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund) and other donors, the ambitious target agreed by G8 leaders in 2005 in Gleneagles to achieve universal access to HIV/AIDS treatment by 2010 has not been reached. Significant barriers to access remain in former Soviet Union (FSU) countries, a region now recognised as a priority area by policymakers. There have been few empirical studies of access to HIV/AIDS services in FSU countries, resulting in limited understanding and implementation of accessible HIV/AIDS interventions. This paper explores the multiple access barriers to HIV/AIDS services experienced by a key risk group-injecting drug users (IDUs). Methods Semi-structured interviews were conducted in two FSU countries-Ukraine and Kyrgyzstan-with clients receiving Global Fund-supported services (Ukraine n = 118, Kyrgyzstan n = 84), service providers (Ukraine n = 138, Kyrgyzstan n = 58) and a purposive sample of national and subnational stakeholders (Ukraine n = 135, Kyrgyzstan n = 86). Systematic thematic analysis of these qualitative data was conducted by country teams, and a comparative synthesis of findings undertaken by the authors. Results Stigmatisation of HIV/AIDS and drug use was an important barrier to IDUs accessing HIV/AIDS services in both countries. Other connected barriers included: criminalisation of drug use; discriminatory practices among government service providers; limited knowledge of HIV/AIDS, services and entitlements; shortages of commodities and human resources; and organisational, economic and geographical barriers. Conclusions Approaches to thinking about universal access frequently assume increased availability of services means increased accessibility of services. Our study demonstrates that while there is greater availability of HIV/AIDS services in Ukraine and Kyrgyzstan, this does not equate with greater accessibility because

  19. Global quantum discord in multipartite systems

    SciTech Connect

    Rulli, C. C.; Sarandy, M. S.

    2011-10-15

    We propose a global measure for quantum correlations in multipartite systems, which is obtained by suitably recasting the quantum discord in terms of relative entropy and local von Neumann measurements. The measure is symmetric with respect to subsystem exchange and is shown to be nonnegative for an arbitrary state. As an illustration, we consider tripartite correlations in the Werner-GHZ (Greenberger-Horne-Zeilinger) state and multipartite correlations at quantum criticality. In particular, in contrast with the pairwise quantum discord, we show that the global quantum discord is able to characterize the infinite-order quantum phase transition in the Ashkin-Teller spin chain.

  20. One-way unlocalizable quantum discord

    NASA Astrophysics Data System (ADS)

    Xi, Zhengjun; Fan, Heng; Li, Yongming

    2012-05-01

    In this paper, we present the concept of the one-way unlocalizable quantum discord and investigate its properties. We provide a polygamy inequality for it in a tripartite pure quantum system of arbitrary dimension. Several tradeoff relations between the one-way unlocalizable quantum discord and other correlations are given. If the von Neumann measurement is made on a part of the system, we give two expressions of the one-way unlocalizable quantum discord in terms of partial distillable entanglement and quantum disturbance. Finally, we also provide a lower bound for bipartite shareability of quantum correlation beyond entanglement in a tripartite system.

  1. Quantum Discord Cannot Be Shared

    NASA Astrophysics Data System (ADS)

    Streltsov, Alexander; Zurek, Wojciech H.

    2013-07-01

    Bohr proposed that the outcome of a measurement becomes objective and real, and, hence, classical, when its results can be communicated by classical means. In this work we revisit Bohr’s postulate using modern tools from quantum information theory. We find a full confirmation of Bohr’s idea: if a measurement device is in a nonclassical state, the measurement results cannot be communicated perfectly by classical means. In this case some part of the information in the measurement apparatus is lost in the process of communication: the amount of this lost information turns out to be the quantum discord. The information loss occurs even when the apparatus is not entangled with the system of interest. The tools presented in this work allow us to generalize Bohr’s postulate: we show that for pure system-apparatus states quantum communication does not provide any advantage when measurement results are communicated to more than one recipient. We further demonstrate the superiority of quantum communication to two recipients on a mixed system-apparatus state and show that this effect is fundamentally different from quantum state cloning.

  2. Union Agitators

    ERIC Educational Resources Information Center

    Honawar, Vaishali

    2006-01-01

    A decade has passed since a few union leaders formed the network known as Teacher Union Reform Network (TURN) to search for innovative ways to enhance education. Selling their message has not always been easy. Created in 1995, TURN was the brain child of Adam Urbanski, the president of the Rochester (N.Y.) Teachers Association for the past 25…

  3. Quantum Discord for d⊗2 Systems

    PubMed Central

    Ma, Zhihao; Chen, Zhihua; Fanchini, Felipe Fernandes; Fei, Shao-Ming

    2015-01-01

    We present an analytical solution for classical correlation, defined in terms of linear entropy, in an arbitrary system when the second subsystem is measured. We show that the optimal measurements used in the maximization of the classical correlation in terms of linear entropy, when used to calculate the quantum discord in terms of von Neumann entropy, result in a tight upper bound for arbitrary systems. This bound agrees with all known analytical results about quantum discord in terms of von Neumann entropy and, when comparing it with the numerical results for 106 two-qubit random density matrices, we obtain an average deviation of order 10−4. Furthermore, our results give a way to calculate the quantum discord for arbitrary n-qubit GHZ and W states evolving under the action of the amplitude damping noisy channel. PMID:26036771

  4. Quantum Discord for d⊗2 Systems.

    PubMed

    Ma, Zhihao; Chen, Zhihua; Fanchini, Felipe Fernandes; Fei, Shao-Ming

    2015-01-01

    We present an analytical solution for classical correlation, defined in terms of linear entropy, in an arbitrary system when the second subsystem is measured. We show that the optimal measurements used in the maximization of the classical correlation in terms of linear entropy, when used to calculate the quantum discord in terms of von Neumann entropy, result in a tight upper bound for arbitrary d⊗2 systems. This bound agrees with all known analytical results about quantum discord in terms of von Neumann entropy and, when comparing it with the numerical results for 10(6) two-qubit random density matrices, we obtain an average deviation of order 10(-4). Furthermore, our results give a way to calculate the quantum discord for arbitrary n-qubit GHZ and W states evolving under the action of the amplitude damping noisy channel. PMID:26036771

  5. Discordant evaluations of Blacks affect nonverbal behavior.

    PubMed

    Olson, Michael A; Fazio, Russell H

    2007-09-01

    Previous research suggests that automatic prejudice directly manifests in nonverbal behavior. The authors offer a more complex picture of the relation between automatic processes and nonverbal behavior by suggesting that any discomfort that appears in nonverbal behavior stems not from negative attitudes per se but from discordance between automatically activated attitudes toward Blacks and the specific evaluations being expressed. White participants for whom estimates of automatic prejudice were available provided videotaped evaluations of several individuals, including two matched Black and White males. Discordance between general racial attitudes and evaluations of specific targets manifested in discomfort-related nonverbal behavior. Moreover, naïve Black judges, but not White judges, doubted the sincerity of individuals characterized by discordance. The nature of the nonverbal "leakage" that automatic prejudice produces is discussed. PMID:17545414

  6. Interpreting quantum discord through quantum state merging

    SciTech Connect

    Madhok, Vaibhav; Datta, Animesh

    2011-03-15

    We present an operational interpretation of quantum discord based on the quantum state merging protocol. Quantum discord is the markup in the cost of quantum communication in the process of quantum state merging, if one discards relevant prior information. Our interpretation has an intuitive explanation based on the strong subadditivity of von Neumann entropy. We use our result to provide operational interpretations of other quantities like the local purity and quantum deficit. Finally, we discuss in brief some instances where our interpretation is valid in the single-copy scenario.

  7. Parental Marital Discord and Treatment Response in Depressed Adolescents

    ERIC Educational Resources Information Center

    Amaya, Meredith M.; Reinecke, Mark A.; Silva, Susan G.; March, John S.

    2011-01-01

    Evidence suggests that parental marital discord contributes to the development of internalizing and externalizing symptoms in children and adolescents. Few studies, however, have examined the association between parental marital discord and youth's response to treatment. The present study examined the impact of interparental discord on treatment…

  8. Screening for acute HIV infection in South Africa: finding acute and chronic disease

    PubMed Central

    Bassett, Ingrid V.; Chetty, Senica; Giddy, Janet; Reddy, Shabashini; Bishop, Karen; Lu, Zhigang; Losina, Elena; Freedberg, Kenneth A.; Walensky, Rochelle P.

    2010-01-01

    Background The yield of screening for acute HIV infection among general medical patients in resource-scarce settings remains unclear. Our objective was to evaluate a strategy of pooled HIV plasma RNA to diagnose acute HIV infection in patients with negative or discordant rapid HIV antibody tests in Durban, South Africa. Methods We prospectively enrolled patients with negative or discordant rapid HIV antibody tests from a routine HIV screening program in an outpatient department in Durban with an HIV prevalence of 48%. Study participants underwent venipuncture for pooled qualitative HIV RNA, and if positive, quantitative RNA, enzyme immunoassay and Western Blot (WB). Patients with negative or indeterminate WB and positive quantitative HIV RNA were considered acutely infected. Those with chronic infection (positive RNA and WB) despite negative or discordant rapid HIV tests were considered false negative rapid antibody tests. Results Nine hundred ninety-four participants were enrolled with either negative (N=976) or discordant (N=18) rapid test results. Eleven (1.1%, 95% CI: 0.6–2.0%) had acute HIV infection. Of the 994 patients, an additional 20 (2.0%, 95% CI: 1.3–.3.1%) had chronic HIV infection (false negative rapid test). Conclusions One percent of outpatients with negative or discordant rapid HIV tests in Durban, South Africa had acute HIV infection readily detectable through pooled serum HIV RNA screening. Pooled RNA testing also identified an additional 2% of patients with chronic HIV infection. HIV RNA screening has the potential to identify both acute and chronic HIV infections that are otherwise missed by standard HIV testing algorithms. PMID:20553336

  9. The social production of substance abuse and HIV/HCV risk: an exploratory study of opioid-using immigrants from the former Soviet Union living in New York City

    PubMed Central

    2012-01-01

    Background Several former Soviet countries have witnessed the rapid emergence of major epidemics of injection drug use (IDU) and associated HIV/HCV, suggesting that immigrants from the former Soviet Union (FSU) may be at heightened risk for similar problems. This exploratory study examines substance use patterns among the understudied population of opioid-using FSU immigrants in the U.S., as well as social contextual factors that may increase these immigrants' susceptibility to opioid abuse and HIV/HCV infection. Methods In-depth interviews were conducted with 10 FSU immigrants living in New York City who initiated opioid use in adolescence or young adulthood, and with 6 drug treatment providers working with this population. Informed by a grounded theory approach, interview transcripts were inductively coded and analyzed to identify key themes. Results The "trauma" of the immigration/acculturation experience was emphasized by participants as playing a critical role in motivating opioid use. Interview data suggest that substance use patterns formed in the high-risk environment of the FSU may persist as behavioral norms within New York City FSU immigrant communities - including a predilection for heroin use among youth, a high prevalence of injection, and a tolerance for syringe sharing within substance-using peer networks. Multiple levels of social context may reproduce FSU immigrants' vulnerability to substance abuse and disease such as: peer-based interactional contexts in which participants typically used opioids; community workplace settings in which some participants were introduced to and obtained opioids; and cultural norms, with roots in Soviet-era social policies, stigmatizing substance abuse which may contribute to immigrants' reluctance to seek disease prevention and drug treatment services. Conclusion Several behavioral and contextual factors appear to increase FSU immigrants' risk for opioid abuse, IDU and infectious disease. Further research on opioid

  10. Monochorionic twins discordant for mosaic trisomy 14.

    PubMed

    He, Mai; Pepperell, John R; Gundogan, Fusun; De Paepe, Monique E; Maggio, Lindsay; Lu, Shaolei; Kostadinov, Stefan; O'Brien, Barbara; Delamonte, Suzanne; Pinar, Halit; Tantravahi, Umadevi

    2014-05-01

    Monochorionic-diamniotic twins are usually monozygotic twins and known to be associated with adverse obstetric and perinatal outcomes. Cases of discordant karyotype of monozygotic twins are rare and most involves sex chromosomes. We present the first case of monochorionic twins with discordant karyotype manifested as mosaic trisomy 14 in one twin (B) and a normal karyotype in the other (A). We describe the postmortem pathological and imaging findings of the trisomic twin and for the first time neuropathological findings of this entity. Metaphase chromosome analysis of twin B using fetal tissue showed a 47,XX, +14 karyotype. Chromosomal microarray analysis (CMA) using fetal tissue revealed 38% mosaicism. CMA with placental tissue from both sides demonstrated normal karyotype and confirmed monozygosity, highlighting the value of array based testing on diagnosing mosaicism and zygosity. PMID:24458767

  11. Sudden change of geometric quantum discord in finite temperature reservoirs

    SciTech Connect

    Hu, Ming-Liang Sun, Jian

    2015-03-15

    We investigate sudden change (SC) behaviors of the distance-based measures of geometric quantum discords (GQDs) for two non-interacting qubits subject to the two-sided and the one-sided thermal reservoirs. We found that the GQDs defined by different distances exhibit different SCs, and thus the SCs are the combined result of the chosen discord measure and the property of a state. We also found that the thermal reservoir may generate states having different orderings related to different GQDs. These inherent differences of the GQDs reveal that they are incompatible in characterizing quantum correlations both quantitatively and qualitatively. - Highlights: • Comparable study of different distance-based geometric quantum discords. • Evolution of the geometric quantum discords in finite temperature reservoirs. • Different geometric quantum discords exhibit distinct sudden changes. • Nonunique states ordering imposed by different geometric quantum discords.

  12. Quantum Discord as a Resource in Quantum Communication

    NASA Astrophysics Data System (ADS)

    Madhok, Vaibhav; Datta, Animesh

    2013-01-01

    As quantum technologies move from the issues of principle to those of practice, it is important to understand the limitations on attaining tangible quantum advantages. In the realm of quantum communication, quantum discord captures the damaging effects of a decoherent environment. This is a consequence of quantum discord quantifying the advantage of quantum coherence in quantum communication. This establishes quantum discord as a resource for quantum communication processes. We discuss this progress, which derives a quantitative relation between the yield of the fully quantum Slepian-Wolf (FQSW) protocol in the presence of noise and the quantum discord of the state involved. The significance of quantum discord in noisy versions of teleportation, super-dense coding, entanglement distillation and quantum state merging are discussed. These results lead to open questions regarding the tradeoff between quantum entanglement and discord in choosing the optimal quantum states for attaining palpable quantum advantages in noisy quantum protocols.

  13. Quantum Discord as a Resource in Quantum Communication

    NASA Astrophysics Data System (ADS)

    Madhok, Vaibhav; Datta, Animesh

    2012-06-01

    As quantum technologies move from the issues of principle to those of practice, it is important to understand the limitations on attaining tangible quantum advantages. In the realm of quantum communication, quantum discord captures the damaging effects of a decoherent environment. This is a consequence of quantum discord quantifying the advantage of quantum coherence in quantum communication. This establishes quantum discord as a resource for quantum communication processes. We discuss this progress, which derives a quantitative relation between the yield of the fully quantum Slepian-Wolf (FQSW) protocol in the presence of noise and the quantum discord of the state involved. The significance of quantum discord in noisy versions of teleportation, super-dense coding, entanglement distillation and quantum state merging are discussed. These results lead to open questions regarding the tradeoff between quantum entanglement and discord in choosing the optimal quantum states for attaining palpable quantum advantages in noisy quantum protocols.

  14. Discord as a quantum resource for bi-partite communication

    NASA Astrophysics Data System (ADS)

    Chrzanowski, Helen M.; Gu, Mile; Assad, Syed M.; Symul, Thomas; Modi, Kavan; Ralph, Timothy C.; Vedral, Vlatko; Lam, Ping Koy

    2014-12-01

    Coherent interactions that generate negligible entanglement can still exhibit unique quantum behaviour. This observation has motivated a search beyond entanglement for a complete description of all quantum correlations. Quantum discord is a promising candidate. Here, we experimentally demonstrate that under certain measurement constraints, discord between bipartite systems can be consumed to encode information that can only be accessed by coherent quantum interactions. The inability to access this information by any other means allows us to use discord to directly quantify this `quantum advantage'.

  15. Relating quantum discord with the quantum dense coding capacity

    SciTech Connect

    Wang, Xin; Qiu, Liang Li, Song; Zhang, Chi; Ye, Bin

    2015-01-15

    We establish the relations between quantum discord and the quantum dense coding capacity in (n + 1)-particle quantum states. A necessary condition for the vanishing discord monogamy score is given. We also find that the loss of quantum dense coding capacity due to decoherence is bounded below by the sum of quantum discord. When these results are restricted to three-particle quantum states, some complementarity relations are obtained.

  16. Relating quantum discord with the quantum dense coding capacity

    NASA Astrophysics Data System (ADS)

    Wang, Xin; Qiu, Liang; Li, Song; Zhang, Chi; Ye, Bin

    2015-01-01

    We establish the relations between quantum discord and the quantum dense coding capacity in ( n + 1)-particle quantum states. A necessary condition for the vanishing discord monogamy score is given. We also find that the loss of quantum dense coding capacity due to decoherence is bounded below by the sum of quantum discord. When these results are restricted to three-particle quantum states, some complementarity relations are obtained.

  17. Geometry and dynamics of one-norm geometric quantum discord

    NASA Astrophysics Data System (ADS)

    Huang, Zhiming; Qiu, Daowen; Mateus, Paulo

    2016-01-01

    We investigate the geometry of one-norm geometric quantum discord and present a geometric interpretation of one-norm geometric quantum discord for a class of two-qubit states. It is found that one-norm geometric quantum discord has geometric behavior different from that described in Lang and Caves (Phys Rev Lett 105:150501, 2010), Li et al. (Phys Rev A 83:022321, 2011) and Yao et al. (Phys Lett A 376:358-364, 2012). We also compare the dynamics of the one-norm geometric quantum discord and other measures of quantum correlations under correlated noise. It is shown that different decoherent channels bring different influences to quantum correlations measured by concurrence, entropic quantum discord and geometric quantum discord, which depend on the memory parameter and decoherence parameter. We lay emphasis on the behaviors such as entanglement sudden death and sudden transition of quantum discord. Finally, we study the dynamical behavior of one-norm geometric quantum discord in one-dimensional anisotropic XXZ model by utilizing the quantum renormalization group method. It is shown that the one-norm geometric quantum discord demonstrates quantum phase transition through renormalization group approach.

  18. A Lower Bound of Quantum Discord for 2-Qutrit Systems

    NASA Astrophysics Data System (ADS)

    Zhang, Qianhui; Wang, Jing; Shen, Shuqian; Li, Ming

    2016-04-01

    We study the lower bound of quantum discord for 2-qutrit systems. By computing the mutual information and the classical correlations of a class of states for 2-qutrit system, an analytical and computable lower bound of discord has been derived. By selecting different coefficients as examples, we can compute the lower bound of discord for 2-qutrit systems directly. The result can be generalized to the case of high-dimensional quantum state and will help us understand and explore the discord of the high-dimensional state.

  19. Sources of gene tree discordance on oryza (poaceae) chromosome 3

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We describe new methods for characterizing gene tree discordance in phylogenomic datasets, which screen for deviations from neutral expectations, summarize variation in statistical support among gene trees, and allow comparison of the patterns of discordance induced by various analysis choices. Usin...

  20. Exploring Knowing/Being through Discordant Professional Practice

    ERIC Educational Resources Information Center

    Dall'Alba, Gloria; Barnacle, Robyn

    2015-01-01

    Despite an increasing array of "quality indicators" and substantial investments in educating professionals, there continues to be clear evidence of discordant, or even negligent, practice by accredited professionals. We refer to discordant professional practice as being "out of tune" with what is accepted as good practice. In a…

  1. Monozygotic twins with trisomy 18: a report of discordant phenotype.

    PubMed Central

    Schlessel, J S; Brown, W T; Lysikiewicz, A; Schiff, R; Zaslav, A L

    1990-01-01

    The predicted incidence of liveborn monozygotic trisomy 18 twins is one per million births. The first case of liveborn monozygotic trisomy 18 twins was reported in 1989 and we report a second case in which striking phenotypic discordance existed. The probability of monozygotic trisomy 18 twinning and the mechanisms for phenotypic discordance in trisomic twins is discussed. Images PMID:2246775

  2. Oxygen isotopic composition and U-Pb discordance in zircon

    USGS Publications Warehouse

    Booth, A.L.; Kolodny, Y.; Chamberlain, C.P.; McWilliams, M.; Schmitt, A.K.; Wooden, J.

    2005-01-01

    We have investigated U-Pb discordance and oxygen isotopic composition of zircon using high-spatial resolution ??18O measurement by ion microprobe. ??18O in both concordant and discordant zircon grains provides an indication of the relationship between fluid interaction and discordance. Our results suggest that three characteristics of zircon are interrelated: (1) U-Pb systematics and concomitant age discordance, (2) ??18O and the water-rock interactions implied therein, and (3) zircon texture, as revealed by cathodoluminescence and BSE imaging. A key observation is that U-Pb-disturbed zircons are often also variably depleted in 18O, but the relationship between discordance and ??18O is not systematic. ??18O values of discordant zircons are generally lighter but irregular in their distribution. Textural differences between zircon grains can be correlated with both U-Pb discordance and ??18O. Discordant grains exhibit either a recrystallized, fractured, or strongly zoned CL texture, and are characteristic of 18O depletion. We interpret this to be a result of metamictization, leading to destruction of the zircon lattice and an increased susceptibility to lead loss. Conversely, grains that are concordant have less-expressed zoning and a smoother CL texture and are enriched in 18O. From this it is apparent that various stages of water-rock interaction, as evidenced by systematic variations in ??18O, leave their imprint on both the texture and U-Pb systematics of zircon. Copyright ?? 2005 Elsevier Ltd.

  3. Multipartite distribution property of one way discord beyond measurement

    NASA Astrophysics Data System (ADS)

    Liu, Si-Yuan; Zhang, Yu-Ran; Yang, Wen-Li; Fan, Heng

    2015-03-01

    We investigate the distribution property of one way discord in the multipartite system by introducing the concept of polygamy deficit for one way discord. The difference between one way discord and quantum discord is analogue to the one between entanglement of assistance and entanglement of formation. For tripartite pure states, two kinds of polygamy deficits are presented with the equivalent expressions and physical interpretations regardless of measurement. For four-partite pure states, we provide a condition which makes one way discord polygamy satisfied. In addition, we generalize these results to the case for N-partite pure states. Those results can be applicable to multipartite quantum systems and are complementary to our understanding of the shareability of quantum correlations.

  4. Discordant and chameleon sequences: their distribution and implications for amyloidogenicity.

    PubMed

    Gendoo, Deena M A; Harrison, Paul M

    2011-03-01

    Identification of ambiguous encoding in protein secondary structure is paramount to develop an understanding of key protein segments underlying amyloid diseases. We investigate two types of structurally ambivalent peptides, which were hypothesized in the literature as indicators of amyloidogenic proteins: discordant α-helices and chameleon sequences. Chameleon sequences are peptides discovered experimentally in different secondary-structure types. Discordant α-helices are α-helical stretches with strong β-strand propensity or prediction. To assess the distribution of these features in known protein structures, and their potential role in amyloidogenesis, we analyzed the occurrence of discordant α-helices and chameleon sequences in nonredundant sets of protein domains (n = 4263) and amyloidogenic proteins extracted from the literature (n = 77). Discordant α-helices were identified if discordance was observed between known secondary structures and secondary-structure predictions from the GOR-IV and PSIPRED algorithms. Chameleon sequences were extracted by searching for identical sequence words in α-helices and β-strands. We defined frustrated chameleons and very frustrated chameleons based on varying degrees of total β propensity ≥α propensity. To our knowledge, this is the first study to discern statistical relationships between discordance, chameleons, and amyloidogenicity. We observed varying enrichment levels for some categories of discordant and chameleon sequences in amyloidogenic sequences. Chameleon sequences are also significantly enriched in proteins that have discordant helices, indicating a clear link between both phenomena. We identified the first set of discordant-chameleonic protein segments we predict may be involved in amyloidosis. We present a detailed analysis of discordant and chameleons segments in the family of one of the amyloidogenic proteins, the Prion Protein. PMID:21432934

  5. Unions, Vitamins, Exercise: Unionized Graduate Students

    ERIC Educational Resources Information Center

    Dewberry, David R.

    2005-01-01

    After the turbulent labor history of America in the early to mid twentieth century, there has been a general decline of unions. Nevertheless, many graduate school teaching assistants are unionizing in attempts to gain better pay and benefits and remove themselves from an "Ivory Sweatshop." This article discusses a history of unions within graduate…

  6. HIV Surveillance in a Large, Community-Based Study: Results from the Pilot Study of Project Accept (HIV Prevention Trials Network 043)

    PubMed Central

    2011-01-01

    Background Project Accept is a community randomized, controlled trial to evaluate the efficacy of community mobilization, mobile testing, same-day results, and post-test support for the prevention of HIV infection in Thailand, Tanzania, Zimbabwe, and South Africa. We evaluated the accuracy of in-country HIV rapid testing and determined HIV prevalence in the Project Accept pilot study. Methods Two HIV rapid tests were performed in parallel in local laboratories. If the first two rapid tests were discordant (one reactive, one non-reactive), a third HIV rapid test or enzyme immunoassay was performed. Samples were designated HIV NEG if the first two tests were non-reactive, HIV DISC if the first two tests were discordant, and HIV POS if the first two tests were reactive. Samples were re-analyzed in the United States using a panel of laboratory tests. Results HIV infection status was correctly determined based on-in country testing for 2,236 (99.5%) of 2,247 participants [7 (0.37%) of 1,907 HIV NEG samples were HIV-positive; 2 (0.63%) of 317 HIV POS samples were HIV-negative; 2 (8.3%) of 24 HIV DISC samples were incorrectly identified as HIV-positive based on the in-country tie-breaker test]. HIV prevalence was: Thailand: 0.6%, Tanzania: 5.0%, Zimbabwe 14.7%, Soweto South Africa: 19.4%, Vulindlela, South Africa: 24.4%, (overall prevalence: 14.4%). Conclusions In-country testing based on two HIV rapid tests correctly identified the HIV infection status for 99.5% of study participants; most participants with discordant HIV rapid tests were not infected. HIV prevalence varied considerably across the study sites (range: 0.6% to 24.4%). Trial Registration ClinicalTrials.gov registry number NCT00203749. PMID:21943026

  7. [HIV and reproductive choices].

    PubMed

    Boer, K; de Vries, J W; de Beaufort, I E

    1995-05-13

    It is estimated that there are about 120-150 hemophilic men infected with HIV in the Netherlands as well as 1000 men infected via intravenous drug use. The majority of them are in reproductive age with relationships with seronegative women. In the event they want to have a child, artificial insemination with donor sperm (KID) is an option. In 1994 there were 147 instances of insemination of 66 women with the processed semen of HIV-positive men and no infection resulted. The annual risk of HIV infection was 7.2% of a woman engaging in unprotected intercourse, according to a prospective Italian study. The risk of HIV infection per contact was estimated at 0.1-5.6%. However, it is not yet proven that processed sperm of an HIV-seropositive man can produce a pregnancy without the risk of infecting the woman. The risk of transmission of HIV to the fetus is higher in artificial insemination of a seropositive woman with the sperm of her partner. In vitro fertilization is not a sure method either for the prevention of HIV infection of the mother because of the possibility of an egg cell being infected before fertilization. HIV-infected pregnant women face the problems of caring for HIV-infected offspring. For HIV discordant couples the advice is to use both condoms for the prevention of infection and oral contraceptives for the prevention of pregnancy. In the case of a lesbian relationship, if the partners want to have a child, HIV infection is still a factor because of previous heterosexual contacts. PMID:7753239

  8. Discord as a quantum resource for bi-partite communication

    SciTech Connect

    Chrzanowski, Helen M.; Assad, Syed M.; Symul, Thomas; Lam, Ping Koy; Gu, Mile; Modi, Kavan; Vedral, Vlatko; Ralph, Timothy C.

    2014-12-04

    Coherent interactions that generate negligible entanglement can still exhibit unique quantum behaviour. This observation has motivated a search beyond entanglement for a complete description of all quantum correlations. Quantum discord is a promising candidate. Here, we experimentally demonstrate that under certain measurement constraints, discord between bipartite systems can be consumed to encode information that can only be accessed by coherent quantum interactions. The inability to access this information by any other means allows us to use discord to directly quantify this ‘quantum advantage’.

  9. Experimental verification of quantum discord in continuous-variable states

    NASA Astrophysics Data System (ADS)

    Hosseini, S.; Rahimi-Keshari, S.; Haw, J. Y.; Assad, S. M.; Chrzanowski, H. M.; Janousek, J.; Symul, T.; Ralph, T. C.; Lam, P. K.

    2014-01-01

    We introduce a simple and efficient technique to verify quantum discord in unknown Gaussian states and a certain class of non-Gaussian states. We show that any separation in the peaks of the marginal distributions of one subsystem conditioned on two different outcomes of homodyne measurements performed on the other subsystem indicates correlation between the corresponding quadratures, and hence nonzero discord. We also apply this method to non-Gaussian states that are prepared by overlapping a statistical mixture of coherent and vacuum states on a beam splitter. We experimentally demonstrate this technique by verifying nonzero quantum discord in a bipartite Gaussian and certain non-Gaussian states.

  10. Witnessing quantum discord in 2xN systems

    SciTech Connect

    Bylicka, Bogna; Chruscinski, Dariusz

    2010-06-15

    Bipartite states with vanishing quantum discord are necessarily separable and hence positive partial transpose (PPT). We show that 2xN states satisfy additional property: the positivity of their partial transposition is recognized with respect to the canonical factorization of the original density operator. We call such states strong PPT (SPPT). Therefore, we provide a natural witness for a quantum discord: if a 2xN state is not SPPT it must contain nonclassical correlations measured by quantum discord. It is an analog of the celebrated Peres-Horodecki criterion: if a state is not PPT it must be entangled.

  11. Entanglement and discord: Accelerated observations of local and global modes

    NASA Astrophysics Data System (ADS)

    Doukas, Jason; Brown, Eric G.; Dragan, Andrzej; Mann, Robert B.

    2013-01-01

    We investigate the amount of entanglement and quantum discord extractable from a two-mode squeezed state as considered from the viewpoint of two observers, Alice (inertial) and Rob (accelerated). We find that using localized modes produces qualitatively different correlation properties for large accelerations than do Unruh modes. Specifically, the entanglement undergoes a sudden death as a function of acceleration, and the discord asymptotes to zero in the limit of infinite acceleration. We conclude that the previous Unruh mode analyses do not determine the acceleration-dependent entanglement and discord degradation of a given quantum state.

  12. Non-Markovian effect on the quantum discord

    SciTech Connect

    Wang Bo; Xu Zhenyu; Chen Zeqian; Feng Mang

    2010-01-15

    We study the non-Markovian effect on the dynamics of the quantum discord by exactly solving a model consisting of two independent qubits subject to two zero-temperature non-Markovian reservoirs, respectively. Considering the two qubits initially prepared in Bell-like or extended Werner-like states, we show that there is no occurrence of the sudden death, but only instantaneous disappearance of the quantum discord at some time points, in comparison to the entanglement sudden death in the same range of the parameters of interest. This implies that the quantum discord is more useful than the entanglement to describe the quantum correlation involved in quantum systems.

  13. State of the Unions

    ERIC Educational Resources Information Center

    Blair, Julie

    2004-01-01

    This article discusses the corrupt leadership of two big-city teachers' unions, the Washington Teachers Union (WTU) and its Miami cousin, United Teachers of Dade (UTD), that took both unions to the brink of despair and financial ruin. While the feds were rifling through union files to build extensive criminal investigations, congress called Sandra…

  14. SI – SRH Sexual-risk factors of partner age-discordance in adolescent girls and their male partners

    PubMed Central

    Morrison-Beedy, Dianne; Xia, Yinglin; Passmore, Denise

    2013-01-01

    Aim and objectives To investigate differences in sexual-risk factors between adolescent girls reporting similar-aged or older sex partners. Background Adolescent girls are at significant risk for heterosexual-acquired HIV infection and other long term reproductive health issues. Sexual partner age-discordance in teen girls has been correlated with STIs, lack of protection, multiple partners, and earlier age of sexual transition. Design A descriptive study comparing girls currently involved with age-discordant partners to those with similar-aged partners. Two-sample t-test for continuous variables and for categorical variables, Chi-square or Fisher exact test were used to compare groups. Methods Baseline data from 738 sexually-active, urban, adolescent girls ages 15 to 19, were analyzed to determine which behaviors were more likely to occur in girls with older partners. Data were collected as part of a gender specific HIV-prevention intervention in a randomized controlled trial tailored to adolescent girls. Results Multiple reported sexual risk behaviors were found to significantly differ between the two groups at baseline. Overall, girls with older partners had more episodes of sexual instances (vaginal, anal, and oral). Specific sexual risk behaviors were found to be statistically significant between the two groups. Girls with older partners started having sex at earlier ages, had more lifetime sexual partners, higher incidents of STIs and were reluctant to discuss using condoms with their partners. Girls with similar-aged partners were less willing to engage in risky sexual behaviors. Conclusions Findings from this investigation support data from other studies. Relationships with older male partners place adolescent girls at increased risk for HIV/STIs and unintended pregnancy. Relevance to clinical practice Adolescent girls in age-discordant relationships are at risk for immediate and long term sexual health morbidities. Identifying girls who are at increased

  15. Parental marital discord and treatment response in depressed adolescents.

    PubMed

    Amaya, Meredith M; Reinecke, Mark A; Silva, Susan G; March, John S

    2011-04-01

    Evidence suggests that parental marital discord contributes to the development of internalizing and externalizing symptoms in children and adolescents. Few studies, however, have examined the association between parental marital discord and youth's response to treatment. The present study examined the impact of interparental discord on treatment response in a randomized control trial of adolescents with major depression enrolled in the Treatment for Adolescents with Depression Study (TADS). Participants were 260 adolescents from two-parent households randomly assigned to one of four treatment groups: fluoxetine (FLX), cognitive behavior therapy (CBT), their combination (COMB), or placebo (PBO). Logistic regressions revealed that parental marital discord interacted with youth gender and co-morbid oppositionality symptoms to predict group differences in treatment response. PMID:20957515

  16. Quantum Entanglement and Quantum Discord in Gaussian Open Systems

    SciTech Connect

    Isar, Aurelian

    2011-10-03

    In the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we give a description of the continuous-variable quantum entanglement and quantum discord for a system consisting of two noninteracting modes embedded in a thermal environment. Entanglement and discord are used to quantify the quantum correlations of the system. For all values of the temperature of the thermal reservoir, an initial separable Gaussian state remains separable for all times. In the case of an entangled initial Gaussian state, entanglement suppression (entanglement sudden death) takes place for non-zero temperatures of the environment. Only for a zero temperature of the thermal bath the initial entangled state remains entangled for finite times. We analyze the time evolution of the Gaussian quantum discord, which is a measure of all quantum correlations in the bipartite state, including entanglement, and show that quantum discord decays asymptotically in time under the effect of the thermal bath.

  17. The potential value of discordant studies

    PubMed Central

    2014-01-01

    Many aspects of the clinical application of gated-single photon emission computed tomography (SPECT) have been well established by multiple trials and studies. However, its utility in the elderly (i.e., the Medicare population in the USA) remains unclear. This is an important population due to its rapid growth, coupled with the increasing prevalence of coronary artery disease with age. A paper in this issue, Predictive value of exercise myocardial perfusion imaging in the Medicare population: the impact of the ability to exercise, indicates that while gated-SPECT clearly directs the performance of interventions at the level of the coronary arteries in the elderly, outcomes are worse for those receiving an intervention vs. those receiving medical therapy. While some literature supports this observation, there are also well documented studies that indicate that the opposite is the case. As consumers of discordant studies, we find ourselves in the unenviable position of having to pull at the threads of evidence and follow them through in an attempt to reconcile the conflicting literature. This is reminiscent of the mythical Gregorian knot, a knot that was impossible to unravel by conventional means. However, it was “solved” by cutting it with a sword. In our case, the sword that we have is the removal of bias. It has been said that there are no unbiased studies, since we only measure what we believe and we tend to believe what we measure. This is further compounded in clinical practice since the Hippocratic Oath requires that the physician above all do no harm. Therefore it follows that whatever action is done is at least not detrimental to the patient. These are powerful belief systems that on the one hand allow us to rapidly discard “irrelevant” information and quickly get to the important point, but on the other hand they may inhibit us from seeing what is truly of value. Discordant and negative studies are important disruptors along the path to easy data

  18. Collapse–revival of quantum discord and entanglement

    SciTech Connect

    Yan, Xue-Qun Zhang, Bo-Ying

    2014-10-15

    In this paper the correlations dynamics of two atoms in the case of a micromaser-type system is investigated. Our results predict certain quasi-periodic collapse and revival phenomena for quantum discord and entanglement when the field is in Fock state and the two atoms are initially in maximally mixed state, which is a special separable state. Our calculations also show that the oscillations of the time evolution of both quantum discord and entanglement are almost in phase and they both have similar evolution behavior in some time range. The fact reveals the consistency of quantum discord and entanglement in some dynamical aspects. - Highlights: • The correlations dynamics of two atoms in the case of a micromaser-type system is investigated. • A quasi-periodic collapse and revival phenomenon for quantum discord and entanglement is reported. • A phenomenon of correlations revivals different from that of non-Markovian dynamics is revealed. • The oscillations of time evolution of both quantum discord and entanglement are almost in phase in our system. • Quantum discord and entanglement have similar evolution behavior in some time range.

  19. Monoamniotic monochorionic twins discordant for noncompaction cardiomyopathy.

    PubMed

    Ng, Dianna; Bouhlal, Yosr; Ursell, Philip C; Shieh, Joseph T C

    2013-06-01

    Occasionally "identical twins" are phenotypically different, raising the question of zygosity and the issue of genetic versus environmental influences during development. We recently noted monochorionic-monoamniotic twins, one of which had an isolated cardiac abnormality, noncompaction cardiomyopathy, a condition characterized by cardiac ventricular hypertrabeculation. We examined the prenatal course and subsequent pathologic correlation since ventricular morphogenesis may depend on early muscular contraction and blood flow. The monochorionic-monoamniotic female twin pair was initially identified since one fetus presented with increased nuchal translucency. Complete heart block was later identified in the fetus with nuchal translucency who did not survive after delivery. In contrast, the unaffected twin had normal cardiac studies both prenatally and postnatally. Pathologic analysis of the affected twin demonstrated noncompaction of the left ventricle with dysplasia of the aortic and pulmonary valves. Dissection of the cardiac conduction system disclosed atrioventricular bundle fibrosis. Maternal lupus studies, amniocentesis with karyotype, and studies for 22q11.2 were normal. To test for zygosity, we performed multiple STR marker analysis and found that all markers were shared even using nonblood tissues from the affected twin. These studies demonstrate that monozygotic twins that are monochorionic monoamniotic can be discordant for cardiac noncompaction. The results suggest further investigation into the potential roles of pathologic fibrosis, contractility, and blood flow in cardiac ventricle development. PMID:23636980

  20. Total lymphoid irradiation and discordant cardiac xenografts

    SciTech Connect

    Kaplan, E.; Dresdale, A.R.; Diehl, J.T.; Katzen, N.A.; Aronovitz, M.J.; Konstam, M.A.; Payne, D.D.; Cleveland, R.J. )

    1990-01-01

    Total lymphoid irradiation can prolong concordant cardiac xenografts. The effects of total lymphoid irradiation in a discordant xenograft model (guinea pig to rat) were studied with and without adjuvant pharmacologic immunosuppression. Inbred Lewis rats were randomly allocated to one of four groups. Group 1 (n = 6) served as a control group and rats received no immunosuppression. Group 2 (n = 5) received triple-drug therapy that consisted of intraperitoneal azathioprine (2 mg/kg), cyclosporine (20 mg/kg), and methylprednisolone (1 mg/kg) for 1 week before transplantation. Group 3 animals (n = 5) received 15 Gy of total lymphoid irradiation in 12 divided doses over a 3-week period. Group 4 (n = 6) received both triple-drug therapy and total lymphoid irradiation as described for groups 2 and 3. Complement-dependent cytotoxicity assay was performed to determine if a correlation between complement-dependent cytotoxicity and rejection-free interval existed. Rejection was defined as cessation of graft pulsation and was confirmed by histologic test results. Only groups 1 and 2 showed a difference in survival (group 1, 6.9 +/- 1.0 minutes; group 2, 14.2 +/- 2.7 minutes, p = 0.02). Although total lymphoid irradiation did decrease complement-dependent cytotoxicity, linear regression revealed no correlation between complement-dependent cytotoxicity and graft survival (coefficient of correlation, 0.30). Unlike concordant cardiac xenografts, total lymphoid irradiation with or without triple-drug therapy does not prolong graft survival.

  1. [Fertility and HIV: equal opportunity for everyone].

    PubMed

    Kedem, Eynat; Shahar, Eduardo; Hassoun, Gammal; Pollack, Shimon

    2013-04-01

    Highly active antiretroviral treatment (HAART), the increase in life expectancy and improved HIV viral detection methods, have all led to a change in attitude towards fertility in people living with HIV. There is now acknowledgment of the fundamental rights of HIV patients to parenthood and growing implementation of assisted fertility in this group. The aims of fertility treatment are prevention of infection in HIV-discordant couples, and treatment for fertility problems, identical to the general population. We review the influence of HIV on the reproduction systems of males and females, conditions requiring fertility intervention, various methods that are possible and describe the optional treatment existing in Israel for patients with viral infection, and specifically HIV. PMID:23844527

  2. Users and Union Catalogues

    ERIC Educational Resources Information Center

    Hartley, R. J.; Booth, Helen

    2006-01-01

    Union catalogues have had an important place in libraries for many years. Their use has been little investigated. Recent interest in the relative merits of physical and virtual union catalogues and a recent collaborative project between a physical and several virtual union catalogues in the United Kingdom led to the opportunity to study how users…

  3. Predictors of First Follow-Up HIV Testing for Couples’ Voluntary HIV Counseling and Testing in Ndola, Zambia

    PubMed Central

    Czaicki, Nancy L; Davitte, Jonathan; Siangonya, Bella; Kastner, Randee; Ahmed, Nurilign; Khu, Naw Htee; Kuo, Wan Hsuan; Abdallah, Joseph; Wall, Kristin M; Tichacek, Amanda; Inambao, Mubiana; Simpungwe, Kakungu; Thior, Ibou; Allen, Susan

    2014-01-01

    Introduction We describe predictors of first follow-up testing for concordant negative and discordant couples seeking joint voluntary HIV counseling and testing in Ndola, Zambia, where cohabiting couples account for an estimated two-thirds of incident HIV infections. Methods Demographic and serostatus data were collected from couples’ voluntary HIV testing and counseling (CVCT) and follow-up testing services implemented in government clinics. We calculated follow-up testing rates by serostatus and compared rates before and after the introduction of a Good Health Package (GHP). Results The follow-up testing rate from May 2011 to December 2012 was 12.2% for concordant negative (M−F−) couples and 24.5% for discordant (M+F− or M−F+) couples. Significant predictors of follow-up testing in multivariate analyses included increasing man’s (aOR=1.02 per year) and woman’s (aOR=1.02) age, the man being HIV+ (aOR=2.57), and the woman being HIV+ (aOR=1.89). The man (aOR=1.29) and the couple (aOR=1.22) having been previously tested for HIV were predictive of follow-up testing among concordant negative couples. Introduction of a GHP increased follow-up testing among discordant (aOR=2.93) and concordant negative (aOR=2.06) couples. Conclusion A low-cost GHP including prevention, screening, and treatment for common causes of morbidity and mortality resulted in increased follow-up testing rates among HIV discordant and concordant negative couples. Overall follow-up testing rates remain low and efforts to increase these rates are necessary in order to ensure linkage to combination prevention, reduce HIV transmission within couples and identify seroconversions promptly. Further investigation of low-cost sustainable incentives and other factors influencing follow-up HIV testing for couples is needed. PMID:24326600

  4. Food Service and the College Union. College Unions at Work.

    ERIC Educational Resources Information Center

    Osterheld, Douglas C.

    This publication, one in a series of monographs on college unions, explores the importance, role, and function of food services in the college union. Major topics discussed include: (1) food service and the college union, (2) union food service and the campus, (3) union food service and the community, (4) organization of union food services, (5)…

  5. On the quantum discord of general X states

    NASA Astrophysics Data System (ADS)

    Yurischev, M. A.

    2015-09-01

    Quantum discord Q is a function of density matrix elements. The domain of such a function in the case of two-qubit system with X density matrix may consist of three subdomains at most: two ones where the quantum discord is expressed in closed analytical forms ( and ) and an intermediate subdomain for which, to extract the quantum discord , it is required to solve numerically a one-dimensional minimization problem to find the optimal measurement angle . Hence, the quantum discord is given by a piecewise analytical-numerical formula . It is shown that the boundaries between the subdomains consist of bifurcation points. The subdomains are discovered in the dynamical phase flip channel model, in the anisotropic spin systems at thermal equilibrium, and in the heteronuclear dimers in an external magnetic field. We found that the transitions between subdomain and and ones occur suddenly, but continuously and smoothly, i.e., nonanalyticity is hidden and can be observed in higher order derivatives of discord function.

  6. Steady state quantum discord for circularly accelerated atoms

    NASA Astrophysics Data System (ADS)

    Hu, Jiawei; Yu, Hongwei

    2015-12-01

    We study, in the framework of open quantum systems, the dynamics of quantum entanglement and quantum discord of two mutually independent circularly accelerated two-level atoms in interaction with a bath of fluctuating massless scalar fields in the Minkowski vacuum. We assume that the two atoms rotate synchronically with their separation perpendicular to the rotating plane. The time evolution of the quantum entanglement and quantum discord of the two-atom system is investigated. For a maximally entangled initial state, the entanglement measured by concurrence diminishes to zero within a finite time, while the quantum discord can either decrease monotonically to an asymptotic value or diminish to zero at first and then followed by a revival depending on whether the initial state is antisymmetric or symmetric. When both of the two atoms are initially excited, the generation of quantum entanglement shows a delayed feature, while quantum discord is created immediately. Remarkably, the quantum discord for such a circularly accelerated two-atom system takes a nonvanishing value in the steady state, and this is distinct from what happens in both the linear acceleration case and the case of static atoms immersed in a thermal bath.

  7. PREDICTORS OF DISCORDANCE BETWEEN PERCEIVED AND OBJECTIVE NEIGHBORHOOD DATA

    PubMed Central

    Bailey, Erin J.; Malecki, Kristen C.; Engelman, Corinne D.; Walsh, Matthew C.; Bersch, Andrew J.; Martinez-Donate, Ana P.; Peppard, Paul E.; Nieto, F. Javier

    2014-01-01

    Purpose Pathways by which the social and built environments affect health can be influenced by differences between perception and reality. This discordance is an important for understanding health impacts of the built environment. This study examines associations between perceived and objective measures of 12 non-residential destinations, as well as previously unexplored sociodemographic, lifestyle, neighborhood and urbanicity predictors of discordance. Methods Perceived neighborhood data were collected from participants of the Survey of the Health of Wisconsin (SHOW), using a self-administered questionnaire. Objective data were collected using the Wisconsin Assessment of the Social and Built Environment, an audit-based instrument assessing built environment features around each participant’s residence. Results Overall, there was relatively high agreement, ranging from 50% for proximity to parks to >90% for golf courses. Education, positive neighborhood perceptions, and rurality were negatively associated with discordance. Associations between discordance and depression, disease status, and lifestyle factors appeared to be modified by urbanicity level. Conclusions These data show perceived and objective neighborhood environment data are not interchangeable and the level of discordance is associated with or modified by individual and neighborhood factors, including level of urbanicity. These results suggest that consideration should be given to including both types of measures in future studies. PMID:24467991

  8. Predicting Discordance Between Self-reports of Sexual Behavior and Incident Sexually Transmitted Infections with African American Female Adolescents: Results from a 4-city Study

    PubMed Central

    Sales, Jessica M.; DiClemente, Ralph J.; Salazar, Laura F.; Vanable, Peter A.; Carey, Michael P.; Brown, Larry K.; Romer, Daniel; Valois, Robert F.; Stanton, Bonita

    2012-01-01

    This study examined correlates of the discordance between sexual behavior self-reports and Incident Sexually Transmitted Infections. African American adolescent females (N = 964) from four U.S. cities were recruited for an HIV/STI prevention trial. Self-reported sexual behaviors, demographics, and hypothesized psychosocial antecedents of sexual risk behavior were collected at baseline, 6-, 12-, and 18-month follow-up assessments. Urine specimens were collected and tested for three prevalent STIs (chlamydia, gonorrhea, trichomonas) at each assessment. Seventeen percent of participants with a laboratory-confirmed STI reported either lifetime abstinence or recent abstinence from vaginal sex (discordant self-report). Lower STI knowledge, belief that fewer peers were engaging in sex, and belief that more peers will wait until marriage to have sex were associated with discordant reports. Discordance between self-reported abstinence and incident STIs was marked among African American female adolescents. Lack of STI knowledge and sexual behavior peer norms may result in underreporting of sexual behaviors. PMID:22323006

  9. HIV serodiscordant relationships in India: Translating science to practice

    PubMed Central

    Solomon, Sunil Suhas; Solomon, Suniti

    2011-01-01

    Over the past 30 years, several interventions have been identified to prevent HIV transmission from HIV-infected persons to uninfected persons in discordant relationships. Yet, transmissions continue to occur. Interventions such as voluntary counselling and testing, condom promotion and risk reduction counselling are very effective in preventing transmission among serodiscordant couples but are underutilized in India despite their widespread availability. New interventions such as pre-risk exposure prophylaxis and universal antiretroviral therapy (irrespective of CD4 count) have been newly identified but face several challenges that impede their widespread implementation in India. Discordant couples in India also face certain unique socio-cultural issues such as marital and fertility pressure. We briefly review the various interventions (existing and novel) available for persons in discordant relationships in India and socio-cultural issues faced by these individuals and make recommendations to maximize their implementation. PMID:22310822

  10. Genetic association mapping based on discordant sib pairs: the discordant-alleles test.

    PubMed

    Boehnke, M; Langefeld, C D

    1998-04-01

    Family-based tests of association provide the opportunity to test for an association between a disease and a genetic marker. Such tests avoid false-positive results produced by population stratification, so that evidence for association may be interpreted as evidence for linkage or causation. Several methods that use family-based controls have been proposed, including the haplotype relative risk, the transmission-disequilibrium test, and affected family-based controls. However, because these methods require genotypes on affected individuals and their parents, they are not ideally suited to the study of late-onset diseases. In this paper, we develop several family-based tests of association that use discordant sib pairs (DSPs) in which one sib is affected with a disease and the other sib is not. These tests are based on statistics that compare counts of alleles or genotypes or that test for symmetry in tables of alleles or genotypes. We describe the use of a permutation framework to assess the significance of these statistics. These DSP-based tests provide the same general advantages as parent-offspring trio-based tests, while being applicable to essentially any disease; they may also be tailored to particular hypotheses regarding the genetic model. We compare the statistical properties of our DSP-based tests by computer simulation and illustrate their use with an application to Alzheimer disease and the apolipoprotein E polymorphism. Our results suggest that the discordant-alleles test, which compares the numbers of nonmatching alleles in DSPs, is the most powerful of the tests we considered, for a wide class of disease models and marker types. Finally, we discuss advantages and disadvantages of the DSP design for genetic association mapping. PMID:9529345

  11. [Discordance analysis of monozygotic twin pairs. Case study on psychogenesis].

    PubMed

    Schepank, H

    1975-01-01

    We performed a discordance-analysis on six pairs of identical twins. They were selected from a large series of neurotic patients who came to visit one of two psychoanalytic outpatient departments. The results of this elaborate case studies are discussed here. The classical twin methods usually will help to clear the question of naturenurture-relation. Contrary to this the aim of discordance-analysis is to proof specific environmental factors which influence development of neurotic illness. The application of this method is rarely possible, because several conditions have to be fullfilled: The patients have to be identical twins; they must be available and willing to undergo psychoanalytic interview; apart from this they must present discordant neurotic complaints.--By a very exact analysis of the early childhood influences we can draw conclusions about psychogenesis of neutotic illness in later life. This method owns extraordinary advantages because of the existence of a control person with identical genetic outfit. PMID:1231414

  12. Quantum discord and entanglement in grover search algorithm

    NASA Astrophysics Data System (ADS)

    Ye, Bin; Zhang, Tingzhong; Qiu, Liang; Wang, Xuesong

    2016-06-01

    Imperfections and noise in realistic quantum computers may seriously affect the accuracy of quantum algorithms. In this article we explore the impact of static imperfections on quantum entanglement as well as non-entangled quantum correlations in Grover's search algorithm. Using the metrics of concurrence and geometric quantum discord, we show that both the evolution of entanglement and quantum discord in Grover algorithm can be restrained with the increasing strength of static imperfections. For very weak imperfections, the quantum entanglement and discord exhibit periodic behavior, while the periodicity will most certainly be destroyed with stronger imperfections. Moreover, entanglement sudden death may occur when the strength of static imperfections is greater than a certain threshold.

  13. Height discordance in monozygotic females is not attributable to discordant inactivation of X-linked stature determining genes.

    PubMed

    Healey, S C; Kirk, K M; Hyland, V J; Munns, C F; Henders, A K; Batch, J A; Heath, A C; Martin, N G; Glass, I A

    2001-02-01

    We tested the hypothesis that X-linked genes determining stature which are subject to skewed or non-random X-inactivation can account for discordance in height in monozygotic female twins. Height discordant female monozygotic adult twins (20 pairs) were identified from the Australian Twin Registry, employing the selection criteria of proven monozygosity and a measured height discordance of at least 5 cm. Differential X-inactivation was examined in genomic DNA extracted from peripheral lymphocytes by estimating differential methylation of alleles at the polymorphic CAG triplet repeat of the Androgen receptor gene (XAR). There were 17/20 MZ pairs heterozygous at this locus and informative for analysis. Of these, 10/17 both had random X-inactivation, 5/17 showed identical X-inactivation patterns of non random inactivation and 2/17 (12%) showed discordant X-inactivation. There was no relationship between inactivation patterns and self-report chorionicity. We conclude that non-random X-inactivation does not appear to be a major contributor to intra-pair height discordance in female MZ twins. PMID:11665320

  14. Gene Tree Discordance Causes Apparent Substitution Rate Variation.

    PubMed

    Mendes, Fábio K; Hahn, Matthew W

    2016-07-01

    Substitution rates are known to be variable among genes, chromosomes, species, and lineages due to multifarious biological processes. Here, we consider another source of substitution rate variation due to a technical bias associated with gene tree discordance. Discordance has been found to be rampant in genome-wide data sets, often due to incomplete lineage sorting (ILS). This apparent substitution rate variation is caused when substitutions that occur on discordant gene trees are analyzed in the context of a single, fixed species tree. Such substitutions have to be resolved by proposing multiple substitutions on the species tree, and we therefore refer to this phenomenon as Substitutions Produced by ILS (SPILS). We use simulations to demonstrate that SPILS has a larger effect with increasing levels of ILS, and on trees with larger numbers of taxa. Specific branches of the species trees are consistently, but erroneously, inferred to be longer or shorter, and we show that these branches can be predicted based on discordant tree topologies. Moreover, we observe that fixing a species tree topology when performing tests of positive selection increases the false positive rate, particularly for genes whose discordant topologies are most affected by SPILS. Finally, we use data from multiple Drosophila species to show that SPILS can be detected in nature. Although the effects of SPILS are modest per gene, it has the potential to affect substitution rate variation whenever high levels of ILS are present, particularly in rapid radiations. The problems outlined here have implications for character mapping of any type of trait, and for any biological process that causes discordance. We discuss possible solutions to these problems, and areas in which they are likely to have caused faulty inferences of convergence and accelerated evolution. PMID:26927960

  15. Sexual discordance and sexual partnering among heterosexual women.

    PubMed

    Nield, Jennifer; Magnusson, Brianna; Brooks, Christopher; Chapman, Derek; Lapane, Kate L

    2015-05-01

    This study examined characteristics of self-identified heterosexual women who were concordant or discordant in their sexual behavior and the association of discordance and sexual partnering among those aged 15-44 years from the 2006-2010 National Survey of Family Growth (n = 7,353). Sexual concordance was defined as reporting a heterosexual identity and no female partners in the past year; discordance was reporting a heterosexual identity and having at least one female partner in the past year. Sexual partnering was defined as being concurrent, serially monogamous or monogamous with a male partner in the previous year. Polytomous logistic regression models evaluated the association between sexual discordance and sexual partnering. Among self-identified heterosexual, sexually active women, 11.2 % reported ever having had a same sex partner. Heterosexually discordant women who had both male and female partners in the previous year were 5.5 times as likely to report having a concurrent relationship (95 % CI 2.77-11.09) and 2.4 times as likely to report engaging in serially monogamous relationships (95 % CI 1.19-4.97) with male partners. Discordance between heterosexual identity and same sex behavior is a factor in risky behaviors. Women who have sex with women and men may act as bridges for the transmission of STDs, particularly to their female partners. Sexual education should include information inclusive of non-heteronormative behaviors and identities to provide sexual minorities with the tools and information they need. Clinical guidelines should ensure that all women are offered counseling and screening for reproductive and sexual health. PMID:24718674

  16. Quantification of quantum discord in a antiferromagnetic Heisenberg compound

    SciTech Connect

    Singh, H. Chakraborty, T. Mitra, C.

    2014-04-24

    An experimental quantification of concurrence and quantum discord from heat capacity (C{sub p}) measurement performed over a solid state system has been reported. In this work, thermodynamic measurements were performed on copper nitrate (CN, Cu(NO{sub 3}){sub 2}⋅2.5H{sub 2}O) single crystals which is an alternating antiferromagnet Heisenberg spin 1/2 system. CN being a weak dimerized antiferromagnet is an ideal system to investigate correlations between spins. The theoretical expressions were used to obtain concurrence and quantum discord curves as a function of temperature from heat capacity data of a real macroscopic system, CN.

  17. How discord underlies the noise resilience of quantum illumination

    NASA Astrophysics Data System (ADS)

    Weedbrook, Christian; Pirandola, Stefano; Thompson, Jayne; Vedral, Vlatko; Gu, Mile

    2016-04-01

    The benefits of entanglement can outlast entanglement itself. In quantum illumination, entanglement is employed to better detect reflecting objects in environments so noisy that all entanglement is destroyed. Here, we show that quantum discord—a more resilient form of quantum correlations—explains the resilience of quantum illumination. We introduce a quantitative relation between the performance gain in quantum illumination and the amount of discord used to encode information about the presence or absence of a reflecting object. This highlights discords role preserving the benefits of entanglement in entanglement breaking noise.

  18. Marital Discord and Subsequent Marital Dissolution: Perceptions of Nepalese Wives and Husbands

    PubMed Central

    Jennings, Elyse

    2014-01-01

    This study examines the influence of marital discord on separation and divorce in a rural South Asian setting. We know little about how marital discord influences marital outcomes in settings with low personal freedom and limited access to independence. Using a sample of 674 couples from the Chitwan Valley Family Study in Nepal, this paper investigates the impact of marital discord on the rate of marital dissolution, and the extent to which wives’ and husbands’ perceptions of discord influence dissolution. Results reveal that (a) spouses’ perceptions of marital discord increase the rate of marital dissolution, (b) both husbands’ and wives’ perceptions of discord have an important influence, and (c) the influence of wives’ perceptions of discord is independent of their husbands’ perceptions. Overall, these findings suggest that both spouses’ perceptions of discord are important for marital outcomes, even in settings where the costs of marital dissolution are relatively high. PMID:25484450

  19. Interparental Conflict and the Children of Discord and Divorce.

    ERIC Educational Resources Information Center

    Emery, Robert E.

    1982-01-01

    Data on the relation between marital turmoil (i.e., discord and divorce) and behavior problems in children are reviewed. Several parameters of this relation are outlined, including type of marital turmoil, form of the child's behavioral response, sex differences, age effects, parental buffering, and effects of parental psychopathology. (Author/MP)

  20. Polygyny and HIV in Malawi

    PubMed Central

    Reniers, Georges; Tfaily, Rania

    2011-01-01

    We review the relationship between polygyny and HIV and identify a positive individual-level correlation, and a negative ecological correlation. We subsequently examine two mechanisms that contribute to the individual-level correlation. First, we find that men in polygynous marriages have more extramarital sex than men in monogamous unions (both in terms of self reports and in terms of spousal reports of the suspicion of adultery). Second, we find evidence of adverse selection of HIV positive women into polygynous unions via an investigation of the relationship between marriage order and polygyny status. We conclude with reflections about possible explanations for the distinct individual and ecological correlations. PMID:21949484

  1. [Unionization on Campus].

    ERIC Educational Resources Information Center

    Douglas, Joel M., Ed.

    1982-01-01

    This newsletter issue considers in separate articles: (1) unionization in 1981 among college faculty in the United States; (2) unionization at the California State University and College System (CSU) (by Lisa Flanzraich); (3) multi-year agreements; (4) contract size; (5) and, in "Yeshivawatch," developments pertaining to the National Labor…

  2. Today's Associations, Tomorrow's Unions.

    ERIC Educational Resources Information Center

    Ichniowski, Casey; Zax, Jeffrey S.

    1990-01-01

    Analysis of census data on local government departments investigated the effects of association-style unionism on union membership. Found that in all local government services, the presence of an association in 1977 was a strong predictor of the formation of a bargaining unit by 1982--holding constant other important determinants of public…

  3. Unions, Contractors and CTE

    ERIC Educational Resources Information Center

    Jarosz, Francesca

    2006-01-01

    Across Illinois, in places where unions thrive, construction industry professionals and career and technical education (CTE) teachers are working together in promoting work-based learning program to students. Likewise, the outreach program provides union-supported contractors with qualified candidates for future employment. Programs such as the…

  4. Unionism and Professionalism: Siblings?

    ERIC Educational Resources Information Center

    Loewenthal, Alfred; Nielsen, Robert

    The controversy surrounding the meaning of professionalism on American campuses is approached by examining the subject from an historical and trade union perspective. It is contended that faculty unions are compatible with professional needs and desires of faculty. The roots of the American college and university system are examined in conjunction…

  5. Teacher Unions 101

    ERIC Educational Resources Information Center

    Koppich, Julia E.

    2012-01-01

    Teacher unions are hard to miss in the news lately. Newspapers, blogs, social media posts, magazine articles, and political speeches abound with talk of them. Teacher unions are a hot topic and one that probably was not covered in college classes. The noisy back-and-forth among partisans can be both mind-numbing and confusing, often creating a…

  6. Sustainability in the Union

    ERIC Educational Resources Information Center

    Brown, Patrick; Taylor, John

    2012-01-01

    Operating as the center of student life, college unions have a central role to teach citizenship, social responsibility, and leadership. Unions can serve as locations for education and conversations about sustainability, as well as for organizations operationally and programmatically engaged in sustainable practices. In this chapter, the authors…

  7. Power in a Union

    ERIC Educational Resources Information Center

    Johnson, Pam

    2009-01-01

    The work unions do in providing and supporting learning for their members rarely makes the news headlines, but it will be essential if people are to engage those workers who most need to acquire new and better skills to cope in the economic downturn. In this article, the author talks about the power in a union and describes UNISON, a comparatively…

  8. Relationship satisfaction of HIV-positive Ugandan individuals with HIV-negative partners.

    PubMed

    Pasipanodya, Elizabeth C; Heatherington, Laurie

    2015-01-01

    Challenges of relational coping are well documented in the literature on couples and chronic illnesses, but there is significantly less research on the psychological aspects of couple relationships and HIV, particularly in international contexts. Coping with the uncertainty of illness progression, family planning, disclosure to friends and family, social isolation and stigma, fear of transmission, sexual intimacy, changes to social and physical functioning, and receiving and providing care pose special challenges for couples with discordant HIV statuses. This study examined the correlates of relationship satisfaction in Ugandan HIV-positive individuals seeking treatment at a community clinic. Relationship satisfaction of HIV-positive individuals was uniquely predicted by their couple identity and depression, underscoring the importance of mental and relational health in HIV/AIDS. PMID:25483813

  9. Comparison of the attempts of quantum discord and quantum entanglement to capture quantum correlations

    SciTech Connect

    Qasimi, Asma Al-; James, Daniel F. V.

    2011-03-15

    Measurements of quantum systems disturb their states. To quantify this nonclassical characteristic, Zurek and Ollivier [Phys. Rev. Lett. 88, 017901 (2001)] introduced the quantum discord, a quantum correlation that can be nonzero even when entanglement in the system is zero. Discord has aroused great interest as a resource that is more robust against the effects of decoherence and offers the exponential speed-up of certain computational algorithms. Here, we study general two-level bipartite systems and give general results on the relationship between discord, entanglement, and linear entropy. We also identify the states for which discord takes a maximal value for a given entropy or entanglement, thus placing strong bounds on entanglement-discord and entropy-discord relations. We find out that although discord and entanglement are identical for pure states, they differ when generalized to mixed states as a result of the difference in the method of generalization.

  10. HIV transmission and related risk factors among serodiscordant couples in Liuzhou, China.

    PubMed

    Zhang, Yu-Jing; Feng, Xian-Xiang; Fan, Yin-Guang; Jiang, Zhi-Yu; Zhong, Xiang-Hai; Li, Ming-Qiang; Ye, Dong-Qing

    2015-04-01

    To evaluate the incidence and risk factors for human immunodeficiency virus (HIV) seroconversion of HIV-negative partners among HIV-discordant couples in Liuzhou, China, 1854 eligible HIV-serodiscordant couples were retrospectively identified through the HIV epidemiology and follow-up database from January 1, 1996 to June 30, 2013. Cox proportional-hazards model was used to examine risk factors related to HIV seroconversion of negative partners. Finally, 125 HIV seroconversion occurred over 4963.5 person-years, resulting in an overall HIV incidence of 2.52/100 person-years. HIV-positive partners with the last CD4 counts of 350 cells/ul or more were significantly protected against HIV seroconversion compared with those CD4 counts of less than 200 cells/ul (aHR = 0.46, 95% CI: 0.27-0.81, P < 0.01). Men with HIV-positive wives (aHR: 1.96, 95% CI: 1.27-3.02, P < 0.01), HIV-positive partners who did not receive ART before their HIV-negative partners' seroconversion (aHR: 2.22, 95% CI, 1.41-3.51, P < 0.01) and patients reported intermittent condom use (aHR: 7.60, 95% CI, 4.37-13.21, P < 0.01) were associated with increased risk of HIV seroconversion. HIV-negative partners remain high risk of HIV infection in Liuzhou city. Comprehensive package of HIV prevention services should contribute to reduction in HIV transmission of discordant couples. PMID:25583348

  11. Monochorionic dizygous twins presenting with blood chimerism and discordant sex.

    PubMed

    Smeets, Dominique; van Vugt, John M G; Gomes, Ingrid; van den Heuvel, Simone; van Heijst, Arno; Reuss, Annette; Claahsen-van der Grinten, Hedi L

    2013-08-01

    Monochorionic dizygous twins are probably more frequent than considered previously as many cases remain unrecognized, especially when the children have the same sex. Here we present a pair of dizygous, sex-discordant monochorionic twins who were conceived after artificial insemination. Histological examination of the placenta and extensive genetic studies of the healthy boy and girl clearly proved that they indeed were monochorionic dizygous twins with a fully joined blood circulation. We conclude that when counseling parents expecting monochorionic twins of discordant sex, not only a disorder of sexual differentiation in one of the twins should be addressed but also the possibility of dizygosity with a completely normal (sexual) development of both children. PMID:23769301

  12. Complementarity of quantum discord and classically accessible information

    DOE PAGESBeta

    Zwolak, Michael P.; Zurek, Wojciech H.

    2013-05-20

    The sum of the Holevo quantity (that bounds the capacity of quantum channels to transmit classical information about an observable) and the quantum discord (a measure of the quantumness of correlations of that observable) yields an observable-independent total given by the quantum mutual information. This split naturally delineates information about quantum systems accessible to observers – information that is redundantly transmitted by the environment – while showing that it is maximized for the quasi-classical pointer observable. Other observables are accessible only via correlations with the pointer observable. In addition, we prove an anti-symmetry property relating accessible information and discord. Itmore » shows that information becomes objective – accessible to many observers – only as quantum information is relegated to correlations with the global environment, and, therefore, locally inaccessible. Lastly, the resulting complementarity explains why, in a quantum Universe, we perceive objective classical reality while flagrantly quantum superpositions are out of reach.« less

  13. Complementarity of quantum discord and classically accessible information

    SciTech Connect

    Zwolak, Michael P.; Zurek, Wojciech H.

    2013-05-20

    The sum of the Holevo quantity (that bounds the capacity of quantum channels to transmit classical information about an observable) and the quantum discord (a measure of the quantumness of correlations of that observable) yields an observable-independent total given by the quantum mutual information. This split naturally delineates information about quantum systems accessible to observers – information that is redundantly transmitted by the environment – while showing that it is maximized for the quasi-classical pointer observable. Other observables are accessible only via correlations with the pointer observable. In addition, we prove an anti-symmetry property relating accessible information and discord. It shows that information becomes objective – accessible to many observers – only as quantum information is relegated to correlations with the global environment, and, therefore, locally inaccessible. Lastly, the resulting complementarity explains why, in a quantum Universe, we perceive objective classical reality while flagrantly quantum superpositions are out of reach.

  14. Gaussian geometric discord in terms of Hellinger distance

    SciTech Connect

    Suciu, Serban Isar, Aurelian

    2015-12-07

    In the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we address the quantification of general non-classical correlations in Gaussian states of continuous variable systems from a geometric perspective. We give a description of the Gaussian geometric discord by using the Hellinger distance as a measure for quantum correlations between two non-interacting non-resonant bosonic modes embedded in a thermal environment. We evaluate the Gaussian geometric discord by taking two-mode squeezed thermal states as initial states of the system and show that it has finite values between 0 and 1 and that it decays asymptotically to zero in time under the effect of the thermal bath.

  15. General monogamy property of global quantum discord and the application

    SciTech Connect

    Liu, Si-Yuan; Zhang, Yu-Ran; Zhao, Li-Ming; Yang, Wen-Li; Fan, Heng

    2014-09-15

    We provide a family of general monogamy inequalities for global quantum discord (GQD), which can be considered as an extension of the usual discord monogamy inequality. It can be shown that those inequalities are satisfied under the similar condition for the holding of usual monogamy relation. We find that there is an intrinsic connection among them. Furthermore, we present a different type of monogamy inequality and prove that it holds under the condition that the bipartite GQDs do not increase when tracing out some subsystems. We also study the residual GQD based on the second type of monogamy inequality. As applications of those quantities, we investigate the GQDs and residual GQD in characterizing the quantum phase transition in the transverse field Ising model.

  16. General monogamy property of global quantum discord and the application

    NASA Astrophysics Data System (ADS)

    Liu, Si-Yuan; Zhang, Yu-Ran; Zhao, Li-Ming; Yang, Wen-Li; Fan, Heng

    2014-09-01

    We provide a family of general monogamy inequalities for global quantum discord (GQD), which can be considered as an extension of the usual discord monogamy inequality. It can be shown that those inequalities are satisfied under the similar condition for the holding of usual monogamy relation. We find that there is an intrinsic connection among them. Furthermore, we present a different type of monogamy inequality and prove that it holds under the condition that the bipartite GQDs do not increase when tracing out some subsystems. We also study the residual GQD based on the second type of monogamy inequality. As applications of those quantities, we investigate the GQDs and residual GQD in characterizing the quantum phase transition in the transverse field Ising model.

  17. Theorizing "Big Events" as a potential risk environment for drug use, drug-related harm and HIV epidemic outbreaks.

    PubMed

    Friedman, Samuel R; Rossi, Diana; Braine, Naomi

    2009-05-01

    Political-economic transitions in the Soviet Union, Indonesia, and China, but not the Philippines, were followed by HIV epidemics among drug users. Wars also may sometimes increase HIV risk. Based on similarities in some of the causal pathways through which wars and transitions can affect HIV risk, we use the term "Big Events" to include both. We first critique several prior epidemiological models of Big Events as inadequately incorporating social agency and as somewhat imprecise and over-generalizing in their sociology. We then suggest a model using the following concepts: first, event-specific HIV transmission probabilities are functions of (a) the probability that partners are infection-discordant; (b) the infection-susceptibility of the uninfected partner; (c) the infectivity of the infected--as well as (d) the behaviours engaged in. These probabilities depend on the distributions of HIV and other variables in populations. Sexual or injection events incorporate risk behaviours and are embedded in sexual and injection partnership patterns and community networks, which in turn are shaped by the content of normative regulation in communities. Wars and transitions can change socio-economic variables that can sometimes precipitate increases in the numbers of people who engage in high-risk drug and sexual networks and behaviours and in the riskiness of what they do. These variables that Big Events affect may include population displacement; economic difficulties and policies; police corruption, repressiveness, and failure to preserve order; health services; migration; social movements; gender roles; and inter-communal violence--which, in turn, affect normative regulation, youth alienation, networks and behaviours. As part of these pathways, autonomous action by neighbourhood residents, teenagers, drug users and sex workers to maintain their economic welfare, health or happiness may affect many of these variables or otherwise mediate whether HIV epidemics follow

  18. Whole-Exome Sequencing in Nine Monozygotic Discordant Twins.

    PubMed

    Zhang, Rong; Thiele, Holger; Bartmann, Peter; Hilger, Alina C; Berg, Christoph; Herberg, Ulrike; Klingmüller, Dietrich; Nürnberg, Peter; Ludwig, Michael; Reutter, Heiko

    2016-02-01

    By definition, monozygotic (MZ) twins carry an identical set of genetic information. The observation of early post-twinning mutational events was shown to cause phenotypic discordance among MZ twin pairs. These mutational events comprise genomic alterations at different scales, ranging from single nucleotide changes to larger copy-number variations (CNVs) of varying sizes, as well as epigenetic changes. Here, we performed whole-exome sequencing (WES) in nine discordant MZ twins to identify somatic mutational events in the affected twin that might exert a dominant negative effect. Five of these MZ twin pairs were discordant for congenital heart defects (CHD), two for endocrine disorders, one for omphalocele, and one for congenital diaphragmatic hernia (CDH). Analysis of WES data from all nine MZ twin pairs using the de novo probability tool DeNovoGear detected only one apparent de novo variation in TMPRSS13 in one of the CHD-affected twins. Analysis of WES data from all nine MZ twin pairs by using standard filter criteria without the de novo probability tool DeNovoGear revealed a total of 6,657 variations in which both the twin pairs differed. After filtering for variations only present in the affected twins and absent in in-house controls, 722 variations remained. Visual inspection for read quality decreased this number to 12, present only in the affected twin. However, Sanger sequencing of the overall 13 variations failed to confirm the variation in the affected twin. These results suggest that somatic mutational events in coding regions do not seem to play a major role in the phenotypic expression of MZ discordant twin pairs. PMID:26681452

  19. Methylomic analysis of monozygotic twins discordant for childhood psychotic symptoms

    PubMed Central

    Fisher, Helen L; Murphy, Therese M; Arseneault, Louise; Caspi, Avshalom; Moffitt, Terrie E; Viana, Joana; Hannon, Eilis; Pidsley, Ruth; Burrage, Joe; Dempster, Emma L; Wong, Chloe C Y; Pariante, Carmine M; Mill, Jonathan

    2015-01-01

    Childhood psychotic symptoms are associated with increased rates of schizophrenia, other psychiatric disorders, and suicide attempts in adulthood; thus, elucidating early risk indicators is crucial to target prevention efforts. There is considerable discordance for psychotic symptoms between monozygotic twins, indicating that child-specific non-genetic factors must be involved. Epigenetic processes may constitute one of these factors and have not yet been investigated in relation to childhood psychotic symptoms. Therefore, this study explored whether differences in DNA methylation at age 10 were associated with monozygotic twin discordance for psychotic symptoms at age 12. The Environmental Risk (E-Risk) Longitudinal Twin Study cohort of 2,232 children (1,116 twin pairs) was assessed for age-12 psychotic symptoms and 24 monozygotic twin pairs discordant for symptoms were identified for methylomic comparison. Children provided buccal samples at ages 5 and 10. DNA was bisulfite modified and DNA methylation was quantified using the Infinium HumanMethylation450 array. Differentially methylated positions (DMPs) associated with psychotic symptoms were subsequently tested in post-mortem prefrontal cortex tissue from adult schizophrenia patients and age-matched controls. Site-specific DNA methylation differences were observed at age 10 between monozygotic twins discordant for age-12 psychotic symptoms. Similar DMPs were not found at age 5. The top-ranked psychosis-associated DMP (cg23933044), located in the promoter of the C5ORF42 gene, was also hypomethylated in post-mortem prefrontal cortex brain tissue from schizophrenia patients compared to unaffected controls. These data tentatively suggest that epigenetic variation in peripheral tissue is associated with childhood psychotic symptoms and may indicate susceptibility to schizophrenia and other mental health problems. PMID:26479702

  20. Plastin 3 expression in discordant spinal muscular atrophy (SMA) siblings.

    PubMed

    Bernal, Sara; Also-Rallo, Eva; Martínez-Hernández, Rebeca; Alías, Laura; Rodríguez-Alvarez, Francisco Javier; Millán, José M; Hernández-Chico, Concepción; Baiget, Montserrat; Tizzano, Eduardo F

    2011-06-01

    Spinal muscular atrophy (SMA) is caused by loss or mutations of the survival motor neuron 1 gene (SMN1). Its highly homologous copy, SMN2, is present in all SMA cases and is a phenotypic modifier. There are cases where asymptomatic siblings of typical SMA patients possess a homozygous deletion of SMN1 just like their symptomatic brothers or sisters. Plastin 3 (PLS3) when over expressed in lymphoblasts from females has been suggested to act as a genetic modifier of SMA. We studied PLS3 expression in four Spanish SMA families with discordant siblings haploidentical for the SMA locus. We excluded PLS3 as a possible modifier in two of our families with female discordant siblings. In the remaining two, we observed small differences in PLS3 expression between male and female discordant siblings. Indeed, we found that values of PLS3 expression in lymphoblasts and peripheral blood ranged from 12 to 200-fold less than those in fibroblasts. These findings warrant further investigation in motor neurons derived from induced pluripotential stem cells of these patients. PMID:21546251

  1. Gut microbiomes of Malawian twin pairs discordant for kwashiorkor

    PubMed Central

    Smith, Michelle I.; Yatsunenko, Tanya; Manary, Mark J.; Trehan, Indi; Mkakosya, Rajhab; Cheng, Jiye; Kau, Andrew L.; Rich, Stephen S.; Concannon, Patrick; Mychaleckyj, Josyf C.; Liu, Jie; Houpt, Eric; Li, Jia V.; Holmes, Elaine; Nicholson, Jeremy; Knights, Dan; Ursell, Luke K.; Knight, Rob; Gordon, Jeffrey I.

    2013-01-01

    Kwashiorkor, an enigmatic form of severe acute malnutrition, is the consequence of inadequate nutrient intake plus additional environmental insults. To investigate the role of the gut microbiome, we studied 317 Malawian twin pairs during the first 3 years of life. During this time, half of the twin pairs remained well-nourished, while 43% became discordant and 7% manifested concordance for acute malnutrition. Both children in twin pairs discordant for kwashiorkor were treated with a peanut-based, ready-to-use therapeutic food (RUTF). Time-series metagenomic studies revealed that RUTF produced a transient maturation of metabolic functions in kwashiorkor microbiomes that regressed when RUTF was stopped. Previously frozen fecal communities from several discordant pairs were each transplanted into gnotobiotic mice. The combination of Malawian diet and kwashiorkor microbiome produced marked weight loss in recipient mice, accompanied by perturbations in amino acid, carbohydrate and intermediary metabolism that were only transiently ameliorated with RUTF. These findings implicate the gut microbiome as a causal factor in kwashiorkor. PMID:23363771

  2. Visual Bias Predicts Gait Adaptability in Novel Sensory Discordant Conditions

    NASA Technical Reports Server (NTRS)

    Brady, Rachel A.; Batson, Crystal D.; Peters, Brian T.; Mulavara, Ajitkumar P.; Bloomberg, Jacob J.

    2010-01-01

    We designed a gait training study that presented combinations of visual flow and support-surface manipulations to investigate the response of healthy adults to novel discordant sensorimotor conditions. We aimed to determine whether a relationship existed between subjects visual dependence and their postural stability and cognitive performance in a new discordant environment presented at the conclusion of training (Transfer Test). Our training system comprised a treadmill placed on a motion base facing a virtual visual scene that provided a variety of sensory challenges. Ten healthy adults completed 3 training sessions during which they walked on a treadmill at 1.1 m/s while receiving discordant support-surface and visual manipulations. At the first visit, in an analysis of normalized torso translation measured in a scene-movement-only condition, 3 of 10 subjects were classified as visually dependent. During the Transfer Test, all participants received a 2-minute novel exposure. In a combined measure of stride frequency and reaction time, the non-visually dependent subjects showed improved adaptation on the Transfer Test compared to their visually dependent counterparts. This finding suggests that individual differences in the ability to adapt to new sensorimotor conditions may be explained by individuals innate sensory biases. An accurate preflight assessment of crewmembers biases for visual dependence could be used to predict their propensities to adapt to novel sensory conditions. It may also facilitate the development of customized training regimens that could expedite adaptation to alternate gravitational environments.

  3. Technology and the Unions.

    ERIC Educational Resources Information Center

    Monaghan, Peter

    1995-01-01

    Faculty union meetings will focus increasingly on the role of technology on college campuses, including adoption of new technologies, assuring support services, clarifying intellectual property issues, and preserving teacher-student contact as teleconferencing and network use grows. (MSE)

  4. ‘Testing Together Challenges the Relationship’: Consequences of HIV Testing as a Couple in a High HIV Prevalence Setting in Rural South Africa

    PubMed Central

    Tabana, Hanani; Doherty, Tanya; Rubenson, Birgitta; Jackson, Debra; Ekström, Anna Mia; Thorson, Anna

    2013-01-01

    Objective We conducted qualitative individual and combined interviews with couples to explore their experiences since the time of taking an HIV test and receiving the test result together, as part of a home-based HIV counselling and testing intervention. Methods This study was conducted in October 2011 in rural KwaZulu-Natal, South Africa, about 2 years after couples tested and received results together. Fourteen couples were purposively sampled: discordant, concordant negative and concordant positive couples. Findings Learning about each other’s status together challenged relationships of the couples in different ways depending on HIV status and gender. The mutual information confirmed suspected infidelity that had not been discussed before. Negative women in discordant partnerships remained with their positive partner due to social pressure and struggled to maintain their HIV negative status. Most of the couple relationships were characterized by silence and mistrust. Knowledge of sero-status also led to loss of sexual intimacy in some couples especially the discordant. For most men in concordant negative couples, knowledge of status was an awakening of the importance of fidelity and an opportunity for behaviour change, while for concordant positive and discordant couples, it was seen as proof of infidelity. Although positive HIV status was perceived as confirmation of infidelity, couples continued their relationship and offered some support for each other, living and managing life together. Sexual life in these couples was characterized by conflict and sometimes violence. In the concordant negative couples, trust was enhanced and behaviour change was promised. Conclusions Findings suggest that testing together as couples challenged relationships in both negative and positive ways. Further, knowledge of HIV status indicated potential to influence behaviour change especially among concordant negatives. In the discordant and concordant positive couples

  5. Gut Microbiota Linked to Sexual Preference and HIV Infection

    PubMed Central

    Noguera-Julian, Marc; Rocafort, Muntsa; Guillén, Yolanda; Rivera, Javier; Casadellà, Maria; Nowak, Piotr; Hildebrand, Falk; Zeller, Georg; Parera, Mariona; Bellido, Rocío; Rodríguez, Cristina; Carrillo, Jorge; Mothe, Beatriz; Coll, Josep; Bravo, Isabel; Estany, Carla; Herrero, Cristina; Saz, Jorge; Sirera, Guillem; Torrela, Ariadna; Navarro, Jordi; Crespo, Manel; Brander, Christian; Negredo, Eugènia; Blanco, Julià; Guarner, Francisco; Calle, Maria Luz; Bork, Peer; Sönnerborg, Anders; Clotet, Bonaventura; Paredes, Roger

    2016-01-01

    The precise effects of HIV-1 on the gut microbiome are unclear. Initial cross-sectional studies provided contradictory associations between microbial richness and HIV serostatus and suggested shifts from Bacteroides to Prevotella predominance following HIV-1 infection, which have not been found in animal models or in studies matched for HIV-1 transmission groups. In two independent cohorts of HIV-1-infected subjects and HIV-1-negative controls in Barcelona (n = 156) and Stockholm (n = 84), men who have sex with men (MSM) predominantly belonged to the Prevotella-rich enterotype whereas most non-MSM subjects were enriched in Bacteroides, independently of HIV-1 status, and with only a limited contribution of diet effects. Moreover, MSM had a significantly richer and more diverse fecal microbiota than non-MSM individuals. After stratifying for sexual orientation, there was no solid evidence of an HIV-specific dysbiosis. However, HIV-1 infection remained consistently associated with reduced bacterial richness, the lowest bacterial richness being observed in subjects with a virological-immune discordant response to antiretroviral therapy. Our findings indicate that HIV gut microbiome studies must control for HIV risk factors and suggest interventions on gut bacterial richness as possible novel avenues to improve HIV-1-associated immune dysfunction. PMID:27077120

  6. Gut Microbiota Linked to Sexual Preference and HIV Infection.

    PubMed

    Noguera-Julian, Marc; Rocafort, Muntsa; Guillén, Yolanda; Rivera, Javier; Casadellà, Maria; Nowak, Piotr; Hildebrand, Falk; Zeller, Georg; Parera, Mariona; Bellido, Rocío; Rodríguez, Cristina; Carrillo, Jorge; Mothe, Beatriz; Coll, Josep; Bravo, Isabel; Estany, Carla; Herrero, Cristina; Saz, Jorge; Sirera, Guillem; Torrela, Ariadna; Navarro, Jordi; Crespo, Manel; Brander, Christian; Negredo, Eugènia; Blanco, Julià; Guarner, Francisco; Calle, Maria Luz; Bork, Peer; Sönnerborg, Anders; Clotet, Bonaventura; Paredes, Roger

    2016-03-01

    The precise effects of HIV-1 on the gut microbiome are unclear. Initial cross-sectional studies provided contradictory associations between microbial richness and HIV serostatus and suggested shifts from Bacteroides to Prevotella predominance following HIV-1 infection, which have not been found in animal models or in studies matched for HIV-1 transmission groups. In two independent cohorts of HIV-1-infected subjects and HIV-1-negative controls in Barcelona (n = 156) and Stockholm (n = 84), men who have sex with men (MSM) predominantly belonged to the Prevotella-rich enterotype whereas most non-MSM subjects were enriched in Bacteroides, independently of HIV-1 status, and with only a limited contribution of diet effects. Moreover, MSM had a significantly richer and more diverse fecal microbiota than non-MSM individuals. After stratifying for sexual orientation, there was no solid evidence of an HIV-specific dysbiosis. However, HIV-1 infection remained consistently associated with reduced bacterial richness, the lowest bacterial richness being observed in subjects with a virological-immune discordant response to antiretroviral therapy. Our findings indicate that HIV gut microbiome studies must control for HIV risk factors and suggest interventions on gut bacterial richness as possible novel avenues to improve HIV-1-associated immune dysfunction. PMID:27077120

  7. [Heterosexual transmission of HIV infection

    PubMed

    Coulaud, J P

    1993-02-01

    The AIDS epidemic has spread rapidly in Africa among the urban impoverished where multiple sexual partners and sexually transmitted diseases are common. Over 80% of the 9 million Africans who will develop AIDS before the year 2000 will have been contaminated sexually. Poverty, multiple sexual partners in the framework of prostitution, and drug addiction are responsible for rapid spread of HIV infection in Southeast Asia, the West India, and Brazil. Drug addiction has played a major role in diffusion of HIV into the general population of Europe and the US. Prevalence rates are much higher in sexually transmitted disease centers in France and the US than among blood donors or pregnant women. Sexually transmitted diseases and heterosexual transmission have been studied in Africas since diagnostic tests became available. Several studies, the majority conducted among prostitutes in Nairobi or Kinshasa and their clients, allow establishment of a list of sexually transmitted diseases associated with increased risk of seroconversion. Genital ulcers within the past 6 months presented a relative risk of 2-4 depending on the series. Urethral or cervical gonorrhea has a lower relative risk of 1.2 in most studies. Absence of circumcision was also a risk factor. Studies were subsequently conducted in Europe on factors favoring sexual transmission. 513 heterosexual couples together for a minimum duration of 18 months and an average of 38 months were included in the Multicenter European Study conducted in 10 centers in 9 countries. The "index" subject was male in 400 cases and female in 113. At entry into the study, 73 of 400 males (18.2%) and 10 of 113 females (8.8%) had already infected their partners. Duration of union, frequency of intercourse, mode of transmission of the index subject, and oral contraceptive use had no effect on risk of transmission. Factors increasing risk of infection included the severity of immunosuppression of the index subject, whether judged by

  8. Quantum discord and geometry for a class of two-qubit states

    SciTech Connect

    Li Bo; Wang Zhixi; Fei Shaoming

    2011-02-15

    We study the level surfaces of quantum discord for a class of two-qubit states with parallel nonzero Bloch vectors. The dynamic behavior of quantum discord under decoherence is investigated. It is shown that a class of X states has sudden transition between classical and quantum correlations under decoherence. Our results include the ones in M. D. Lang and C. M. Caves [Phys. Rev. Lett. 105, 150501 (2010)] as a special case and show new pictures and structures of quantum discord.

  9. Distribution of geometric quantum discord in photon-added coherent states

    NASA Astrophysics Data System (ADS)

    Daoud, M.; Kaydi, W.; El Hadfi, H.

    2015-12-01

    In this paper, we examine the influence of photon excitation on the monogamy property of quantum discord in tripartite coherent states of Greenberger-Horne-Zeilinger (GHZ) type. The Hilbert-Schmidt norm is used as quantifier of pairwise quantum correlations. The geometric quantum discord in all bipartite subsystems are explicitly given. We show that the geometric discord is monogamous for any photon excitation order.

  10. Gender and HIV infection in the context of alcoholism in Kenya.

    PubMed

    Muturi, Nancy

    2015-01-01

    Women in sub-Saharan Africa account for more than half (58%) of people living with the HIV and it is the only continent where HIV prevalence is higher for women than for men. Studies have attributed alcoholism with the high rates of HIV infection due to its impact on sexual behaviour and arousal. African countries with high rates of alcoholism also reportedly have higher rates of HIV infection. This study explores rural communities' perspectives on the risk factors for HIV infection among women who are in alcohol discordant relationships where the man drinks alcohol excessively. Data were gathered through focus group discussions in rural central Kenya where alcoholism has reached epidemic levels. Key findings indicate the perceived severity of alcoholism, the perceived impact of alcoholism on men's reproductive health and the unmet sexual and reproductive needs of women in alcohol discordant relationships. Women engage in risky sexual behaviours in an attempt to meet these needs. Such risky behaviour in addition to alcohol-related sexual violence and low response-efficacy for safer sexual practices make them vulnerable to HIV infection and enhances the spread of HIV within communities. The study concludes that in preventing HIV infection among women in alcohol communities affected by alcohol, it is important to focus on their response efficacy. Intervention programmes that focus on HIV prevention among older married women and that integrate alcohol and HIV prevention are long overdue. PMID:25920984

  11. Quantum discord as a resource for quantum cryptography.

    PubMed

    Pirandola, Stefano

    2014-01-01

    Quantum discord is the minimal bipartite resource which is needed for a secure quantum key distribution, being a cryptographic primitive equivalent to non-orthogonality. Its role becomes crucial in device-dependent quantum cryptography, where the presence of preparation and detection noise (inaccessible to all parties) may be so strong to prevent the distribution and distillation of entanglement. The necessity of entanglement is re-affirmed in the stronger scenario of device-independent quantum cryptography, where all sources of noise are ascribed to the eavesdropper. PMID:25378231

  12. Entanglement, discord, and the power of quantum computation

    SciTech Connect

    Brodutch, Aharon; Terno, Daniel R.

    2011-01-15

    We show that the ability to create entanglement is necessary for execution of bipartite quantum gates even when they are applied to unentangled states and create no entanglement. Starting with a simple example we demonstrate that to execute such a gate bilocally the local operations and classical communications (LOCC) should be supplemented by shared entanglement. Our results point to the changes in quantum discord, which is a measure of quantumness of correlations even in the absence of entanglement, as the indicator of failure of a LOCC implementation of the gates.

  13. Epigenetic differences in monozygotic twins discordant for major depressive disorder.

    PubMed

    Malki, K; Koritskaya, E; Harris, F; Bryson, K; Herbster, M; Tosto, M G

    2016-01-01

    Although monozygotic (MZ) twins share the majority of their genetic makeup, they can be phenotypically discordant on several traits and diseases. DNA methylation is an epigenetic mechanism that can be influenced by genetic, environmental and stochastic events and may have an important impact on individual variability. In this study we explored epigenetic differences in peripheral blood samples in three MZ twin studies on major depressive disorder (MDD). Epigenetic data for twin pairs were collected as part of a previous study using 8.1-K-CpG microarrays tagging DNA modification in white blood cells from MZ twins discordant for MDD. Data originated from three geographical regions: UK, Australia and the Netherlands. Ninety-seven MZ pairs (194 individuals) discordant for MDD were included. Different methods to address non independently-and-identically distributed (non-i.i.d.) data were evaluated. Machine-learning methods with feature selection centered on support vector machine and random forest were used to build a classifier to predict cases and controls based on epivariations. The most informative variants were mapped to genes and carried forward for network analysis. A mixture approach using principal component analysis (PCA) and Bayes methods allowed to combine the three studies and to leverage the increased predictive power provided by the larger sample. A machine-learning algorithm with feature reduction classified affected from non-affected twins above chance levels in an independent training-testing design. Network analysis revealed gene networks centered on the PPAR-γ (NR1C3) and C-MYC gene hubs interacting through the AP-1 (c-Jun) transcription factor. PPAR-γ (NR1C3) is a drug target for pioglitazone, which has been shown to reduce depression symptoms in patients with MDD. Using a data-driven approach we were able to overcome challenges of non-i.i.d. data when combining epigenetic studies from MZ twins discordant for MDD. Individually, the studies yielded

  14. Epigenetic differences in monozygotic twins discordant for major depressive disorder

    PubMed Central

    Malki, K; Koritskaya, E; Harris, F; Bryson, K; Herbster, M; Tosto, M G

    2016-01-01

    Although monozygotic (MZ) twins share the majority of their genetic makeup, they can be phenotypically discordant on several traits and diseases. DNA methylation is an epigenetic mechanism that can be influenced by genetic, environmental and stochastic events and may have an important impact on individual variability. In this study we explored epigenetic differences in peripheral blood samples in three MZ twin studies on major depressive disorder (MDD). Epigenetic data for twin pairs were collected as part of a previous study using 8.1-K-CpG microarrays tagging DNA modification in white blood cells from MZ twins discordant for MDD. Data originated from three geographical regions: UK, Australia and the Netherlands. Ninety-seven MZ pairs (194 individuals) discordant for MDD were included. Different methods to address non independently-and-identically distributed (non-i.i.d.) data were evaluated. Machine-learning methods with feature selection centered on support vector machine and random forest were used to build a classifier to predict cases and controls based on epivariations. The most informative variants were mapped to genes and carried forward for network analysis. A mixture approach using principal component analysis (PCA) and Bayes methods allowed to combine the three studies and to leverage the increased predictive power provided by the larger sample. A machine-learning algorithm with feature reduction classified affected from non-affected twins above chance levels in an independent training-testing design. Network analysis revealed gene networks centered on the PPAR−γ (NR1C3) and C-MYC gene hubs interacting through the AP-1 (c-Jun) transcription factor. PPAR−γ (NR1C3) is a drug target for pioglitazone, which has been shown to reduce depression symptoms in patients with MDD. Using a data-driven approach we were able to overcome challenges of non-i.i.d. data when combining epigenetic studies from MZ twins discordant for MDD. Individually, the studies

  15. Quantifying quantum discord and entanglement of formation via unified purifications

    SciTech Connect

    Cen Lixiang; Li Xinqi; Shao Jiushu; Yan Yijing

    2011-05-15

    We propose a scheme to evaluate the amount of quantum discord and entanglement of formation for mixed states and reveal their ordering relation via an intrinsic relationship between the two quantities distributed in the purification of different states. This approach enables us to achieve analytical expressions of the two measures for some quantum states, such as an arbitrary two-qubit density matrix reduced from pure three-qubit states and a class of rank-2 mixed states of 4x2 systems. Moreover, we apply the scheme to characterize fully the dynamic behavior of quantum correlations for the specified physical systems under decoherence.

  16. Quantum Discord of 2 n -Dimensional Bell-Diagonal States

    NASA Astrophysics Data System (ADS)

    Jafarizadeh, M. A.; Karimi, N.; Amidi, D.; Zahir Olyaei, H.

    2016-03-01

    In this study, using the concept of relative entropy as a distance measure of correlations we investigate the important issue of evaluating quantum correlations such as entanglement, dissonance and classical correlations for 2 n -dimensional Bell-diagonal states. We provide an analytical technique, which describes how we find the closest classical states(CCS) and the closest separable states(CSS) for these states. Then analytical results are obtained for quantum discord of 2 n -dimensional Bell-diagonal states. As illustration, some special cases are examined. Finally, we investigate the additivity relation between the different correlations for the separable generalized Bloch sphere states.

  17. HIV Symptoms

    MedlinePlus

    ... Submit Home > HIV/AIDS > What is HIV/AIDS? HIV/AIDS This information in Spanish ( en español ) HIV symptoms Photo courtesy of AIDS.gov More information ... and brain Return to top More information on HIV symptoms Explore other publications and websites Basic Information ...

  18. Adolescent Alcohol Abuse and Adverse Adult Outcomes: Evaluating Confounds with Drinking-Discordant Twins

    PubMed Central

    Rose, Richard J.; Winter, Torsten; Viken, Richard J.; Kaprio, Jaakko

    2014-01-01

    Background Adolescent alcohol abuse is associated with adverse outcomes in early adulthood, but differences in familial status and structure and household and community environments correlate with both adolescent drinking and adverse adult outcomes and may explain their association. We studied drinking-discordant twin pairs to evaluate such confounds to ask: Will between-family associations replicate in within-family comparisons? Methods With longitudinal data from > 3,000 Finnish twins, we associated drinking problems at age 18½ with 13 outcomes assessed at age 25; included were sustained substance abuse, poor health, physical symptoms, early coital debut, multiple sexual partners, life dissatisfaction, truncated education, and financial problems. We assessed associations among twins as individuals with linear regression adjusted for correlated observations; within-family analyses of discordant twin pairs followed, comparing paired means for adult outcomes among co-twins discordant for adolescent problem drinking. Defining discordance by extreme scores on self-reported problem drinking at age 18½ permitted parallel analyses of twins as individuals and discordant twin pairs. Alternate definitions of pair-wise discordance and difference score correlations across the entire twin sample yielded supplementary analyses. Results All individual associations were highly significant for all definitions of discordance we employed. Depending on definitions of discordance, 11 to 13 comparisons of all drinking-discordant twin pairs and 3 to 6 comparisons of discordant monozygotic twin pairs replicated between-family associations. For most outcomes, effect size attenuated from individual level analysis to that within discordant MZ twin pairs providing evidence of partial confounding in associations reported in earlier research. The exception was the General Health Questionnaire; at age 25, GHQ-12 had equivalent associations with age 18½ RAPI across all comparisons

  19. HIV Prevention

    MedlinePlus

    ... to treat HIV infection (called antiretroviral therapy, or ART) the right way, every day and his or ... way, every day, the medicine to treat HIV (ART) reduces the amount of HIV (called “viral ...

  20. Unionism and American Education.

    ERIC Educational Resources Information Center

    Spring, Joel

    Organized labor in the United States has been divided in the types of economic solutions it has sought for the working class and in the type of support it has given education. In terms of education, rightwing unionism has tended to accept the basic structure of American education and the general ideology of equality of opportunity. Leftwing…

  1. Faculty Unionism and Tenure

    ERIC Educational Resources Information Center

    McHugh, William F.

    1973-01-01

    With reference to personal experience, labor board decisions, and faculty collective bargaining agreements, the author discusses the causes of faculty unionism, what constitutes a tenure system and what problems it creates, what is involved in the bargaining process, and the implications involved in negotiating tenure. (JT)

  2. Marketing the College Union.

    ERIC Educational Resources Information Center

    Hoef, Ted; Howe, Nanci

    Theory underlying marketing in the public sector is presented in combination with specific examples of marketing strategies and techniques used in college unions and student activities programs across the country. The subject of marketing is discussed under six major subject headings: (1) why marketing? (2) analyzing marketing opportunities; (3)…

  3. Unions and Workplace Reorganization.

    ERIC Educational Resources Information Center

    Nissen, Bruce, Ed.

    The 11 chapters in this book focus on "The New American Workplace" and assess its adequacy or inadequacy as a guide for the U.S. labor movement in relation to new work systems. "Unions and Workplace Reorganization" (Bruce Nissen) introduces the subject. "The New American Workplace: A Labor Perspective" (AFL-CIO Committee on the Evolution of Work,…

  4. Unions, Solidarity, and Striking

    ERIC Educational Resources Information Center

    Dixon, Marc; Roscigno, Vincent J.; Hodson, Randy

    2004-01-01

    Organizational resources and group solidarity are central foci in literature on social movements generally and worker insurgency specifically. Research, however, seldom deals with both simultaneously and their potential interrelations. In this article, we examine the complex relationships between union organization and worker solidarity relative…

  5. Trade Union Rights.

    ERIC Educational Resources Information Center

    Maier, Heribert; And Others

    1994-01-01

    Excerpts addresses from an international symposium regarding workers' education, human rights, labor standards and law, socioeconomic factors, trade unions, workers' rights, professionalism, and globalization. Includes a background paper, "Participation of Workers and Their Organizations in the Field of International Labour Standards and the…

  6. Arguments for and against HIV self-testing

    PubMed Central

    Wood, Brian R; Ballenger, Carl; Stekler, Joanne D

    2014-01-01

    Approximately 60% of human immunodeficiency virus (HIV)-infected individuals are unaware of their infection, and stigma and discrimination continue to threaten acceptance of HIV testing services worldwide. Self-testing for HIV has garnered controversy for years and the debate reignited with the approval of a point-of-care test for over-the-counter sale in the US in 2012. Here, we present arguments for and against HIV self-testing. The case in support of HIV self-testing contends that: the modality is highly acceptable, especially among the most at-risk individuals; self-testing empowers users, thus helping to normalize testing; and mutual partner testing has the potential to increase awareness of risk and avert condomless sex between discordant partners. Arguments against HIV self-testing include: cost limits access to those who need testing most; false-negative results, especially during the window period, may lead to false reassurance and could promote sex between discordant partners at the time of highest infectivity; opportunities for counseling, linkage to care, and diagnosis of other sexually transmitted infections may be missed; and self-testing leads to potential for coercion between partners. Research is needed to better define the risks of self-testing, especially as performance of the assays improves, and to delineate the benefits of programs designed to improve access to self-test kits, because this testing modality has numerous potential advantages and drawbacks. PMID:25114592

  7. A Generalized Geometric Measurement of Quantum Discord: Exact Treatment

    NASA Astrophysics Data System (ADS)

    Cui, Hai-Tao; Tian, Jun-Long; Yang, Gui

    2016-02-01

    A generalization of the geometric measure of quantum discord is introduced in this article, based on Hellinger distance. Our definition has virtues of computability and independence of local measurement. In addition it also does not suffer from the recently raised critiques about quantum discord. The exact result can be obtained for bipartite pure states with arbitrary levels, which is completely determined by the Schmidt decomposition. For bipartite mixed states the exact result can also be found for a special case. Furthermore the generalization into multipartite case is direct. It is shown that it can be evaluated exactly when the measured state is invariant under permutation or translation. In addition the detection of quantum phase transition is also discussed for Lipkin-Meshkov-Glick and Dicke model. Supported by National Natural Science Foundation of China under Grant No. 11005002 and 11475004, New Century Excellent Talent of M.O.E (NCET-11-0937), and Sponsoring Program of Excellent Younger Teachers in universities in Henan Province under Grant No. 2010GGJS-181

  8. A Generalized Geometric Measurement of Quantum Discord: Exact Treatment

    NASA Astrophysics Data System (ADS)

    Cui, Hai-Tao; Tian, Jun-Long; Yang, Gui

    2016-02-01

    A generalization of the geometric measure of quantum discord is introduced in this article, based on Hellinger distance. Our definition has virtues of computability and independence of local measurement. In addition it also does not suffer from the recently raised critiques about quantum discord. The exact result can be obtained for bipartite pure states with arbitrary levels, which is completely determined by the Schmidt decomposition. For bipartite mixed states the exact result can also be found for a special case. Furthermore the generalization into multipartite case is direct. It is shown that it can be evaluated exactly when the measured state is invariant under permutation or translation. In addition the detection of quantum phase transition is also discussed for Lipkin–Meshkov–Glick and Dicke model. Supported by National Natural Science Foundation of China under Grant No. 11005002 and 11475004, New Century Excellent Talent of M.O.E (NCET-11-0937), and Sponsoring Program of Excellent Younger Teachers in universities in Henan Province under Grant No. 2010GGJS-181

  9. Monozygotic twin sisters discordant for familial hemiplegic migraine

    PubMed Central

    2013-01-01

    Background The high concordance rate of migraine in monozygotic twin pairs has long been recognised. In the current study, we present a monozygotic twin pair discordant for familial hemiplegic migraine (FHM). Case presentations We evaluated 12 adult family members in 2012. The twin pair was separately examined by neurologists at different time points. Mutation screening was performed for known FHM-related genes. The monozygosity of the twins was verified. Eleven individuals had a history of migraine or paroxysmal neurological symptoms, including four patients with motor aura. No mutations were detected in the CACNA1A, ATP1A2, SCN1A, PRRT2 or NOTCH3 genes. The monozygotic twin sisters, aged 52, were discordant for age of onset, motor aura and neuropsychological aura (forced thinking). Overall, the family members presented a wide range of phenotypical features. Conclusions Familial hemiplegic migraine is a monogenic disorder that is distinct from migraine with typical aura. However, in certain families with motor aura, such as this one, it is possible that the most severe phenotype is caused by an unlikely combination of polygenic traits and non-genetic factors. In these kindreds, we propose that hemiplegic aura is only a severe and complex form of typical aura. PMID:24041236

  10. The Australian Education Union and Teacher Union Modernization.

    ERIC Educational Resources Information Center

    Spaull, Andrew

    1998-01-01

    Examines some of the directions that modernization of teacher unionism has taken in the 1990s, explaining that the 1990s has been the decade of the Australian Education Union (AEU). The paper describes the AEU and looks at organizational changes within the AEU, industrial roles, and political roles that affect today's teacher unions in Australia.…

  11. Teacher Unions and Parent Involvement. EPI Series on Teacher Unions.

    ERIC Educational Resources Information Center

    Haar, Charlene K.

    This booklet, part of the Education Policy Institute series about teacher union issues, clarifies the concept of parent involvement in educational reform, analyzing the treatment of parents in collective bargaining contracts between teacher unions and school boards and in union policy resolutions. Chapter 1 introduces the issue, offering an…

  12. New Roles for Teachers Unions? Reform Unionism in School Decentralization

    ERIC Educational Resources Information Center

    Donaldson, Morgaen L.; Mayer, Anysia P.; Cobb, Casey D.; LeChasseur, Kimberly; Welton, Anjale

    2013-01-01

    Of late, teachers unions have worked together with district management in new and notable ways. This paper examines the role of teachers unions in shaping the Together Initiative (TI), which seeks to increase autonomy and broaden decision making in urban schools in one northeastern state. In general, state-level union leaders have taken more…

  13. Family Discord, Parental Depression, and Psychopathology in Offspring: 20-Year Follow-up

    ERIC Educational Resources Information Center

    Pilowsky, Daniel J.; Wickramaratne, Priya; Nomura, Yoko; Weissman, Myrna M.

    2006-01-01

    Objective: To determine the independent effects of parental depression and family discord on offspring psychopathology among children at high and low risk of depression. Method: Family discord factors were assessed when subjects were approximately 17 years old, and offspring diagnoses were assessed about 20 years later. Parental and offspring…

  14. Disentangling methodological and biological sources of gene tree discordance on oryza (poaceae) chromosome 3

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We describe new methods for characterizing gene tree discordance in phylogenomic datasets, which screen for deviations from neutral expectations, summarize variation in statistical support among gene trees, and allow comparison of the patterns of discordance induced by various analysis choices. Usin...

  15. Parental Discord vs. Family Structure: Effects of Divorce on the Self-Esteem of Daughters.

    ERIC Educational Resources Information Center

    Long, Barbara H.

    1986-01-01

    The effects of family structure and parental discord on the self-esteem of 199 female undergraduates were investigated. Family structure and happiness ratings were substantially related, with those separated rated as less happy. Parental discord appeared to lower the self-esteem of daughters, whereas separation of parents did not. (Author/LMO)

  16. Likely female-to-female sexual transmission of HIV--Texas, 2012.

    PubMed

    Chan, Shirley K; Thornton, Lupita R; Chronister, Karen J; Meyer, Jeffrey; Wolverton, Marcia; Johnson, Cynthia K; Arafat, Raouf R; Joyce, Patricia M; Switzer, William M; Heneine, Walid; Shankar, Anupama; Granade, Timothy; Owen, Michele S; Sprinkle, Patrick; Sullivan, Vickie

    2014-03-14

    In August 2012, the Houston Department of Health contacted CDC regarding the rare transmission of human immunodeficiency virus (HIV) likely by sexual contact between two women. The case was investigated, and laboratory testing confirmed that the woman with newly diagnosed HIV infection had a virus virtually identical to that of her female partner, who was diagnosed previously with HIV and who had stopped receiving antiretroviral treatment in 2010. This report describes this case of HIV infection, likely acquired by female-to-female sexual transmission during the 6-month monogamous relationship of the HIV-discordant couple (one negative, one positive). The woman with newly acquired infection did not report any other recognized risk factors for HIV infection, and the viruses infecting the two women had ≥ 98% sequence identity in three genes. The couple had not received any preventive counseling before acquisition of the virus by the woman who had tested negative for HIV. HIV-discordant couples should receive counseling regarding safer sex practices, and HIV-infected partners should be linked to and retained in medical care. PMID:24622284

  17. Application of two tests of multivariate discordancy to fisheries data sets

    USGS Publications Warehouse

    Stapanian, M.A.; Kocovsky, P.M.; Garner, F.C.

    2008-01-01

    The generalized (Mahalanobis) distance and multivariate kurtosis are two powerful tests of multivariate discordancies (outliers). Unlike the generalized distance test, the multivariate kurtosis test has not been applied as a test of discordancy to fisheries data heretofore. We applied both tests, along with published algorithms for identifying suspected causal variable(s) of discordant observations, to two fisheries data sets from Lake Erie: total length, mass, and age from 1,234 burbot, Lota lota; and 22 combinations of unique subsets of 10 morphometrics taken from 119 yellow perch, Perca flavescens. For the burbot data set, the generalized distance test identified six discordant observations and the multivariate kurtosis test identified 24 discordant observations. In contrast with the multivariate tests, the univariate generalized distance test identified no discordancies when applied separately to each variable. Removing discordancies had a substantial effect on length-versus-mass regression equations. For 500-mm burbot, the percent difference in estimated mass after removing discordancies in our study was greater than the percent difference in masses estimated for burbot of the same length in lakes that differed substantially in productivity. The number of discordant yellow perch detected ranged from 0 to 2 with the multivariate generalized distance test and from 6 to 11 with the multivariate kurtosis test. With the kurtosis test, 108 yellow perch (90.7%) were identified as discordant in zero to two combinations, and five (4.2%) were identified as discordant in either all or 21 of the 22 combinations. The relationship among the variables included in each combination determined which variables were identified as causal. The generalized distance test identified between zero and six discordancies when applied separately to each variable. Removing the discordancies found in at least one-half of the combinations (k=5) had a marked effect on a principal components

  18. Pediatric Residents' Perspective on Family-Clinician Discordance in Primary Care: A Qualitative Study.

    PubMed

    Rosenthal, Marjorie S; Connor, Katherine A; Fenick, Ada M

    2016-01-01

    The engagement of families in health maintenance is associated with better child health outcomes, but demographic discordance between families and clinicians may be a barrier to family engagement. Using a longitudinal qualitative study design, we conducted 15 semi-structured interviews with five pediatric residents who elected to facilitate group well child care (GWCC). Four themes describing residents' perceptions of the role of discordance in family-clinician engagement include: 1) discordance was not a barrier; 2) discordance leads to a lack of engagement and trust; 3) residents transcended discordance in GWCC because either GWCC led residents to change their communication techniques or because, with GWCC, parents have concordant adults in the room; and 4) the education residents obtained in GWCC allowed them to empathize with the families' health-related decisions. Finding ways in which pediatric providers can improve skills in family engagement may be an important step in decreasing health inequities. PMID:27524749

  19. Racial Discrimination and Trade Unionism

    ERIC Educational Resources Information Center

    Ashenfelter, Orley

    1972-01-01

    Analyzes the likely determinants of a trade union's policy regarding race and estimates the effect of the presence of unionism on the average wage of black workers relative to that of white workers under various types of union organizational structure. (RJ)

  20. What's Wrong with Teacher Unions.

    ERIC Educational Resources Information Center

    Urban, Wayne J.

    1998-01-01

    Responds and takes exception to the assumptions and arguments of Myron Lieberman, who argues against teacher unionism and says it is the major obstacle to educational reform. After summarizing Lieberman's discussion of contemporary teacher unions, concludes that Lieberman is biased against teacher unions in his analysis of their contemporary…

  1. Union Members Are Community Members

    ERIC Educational Resources Information Center

    Gray, David

    2013-01-01

    Unions serve their members' interests. But union members are also community members, and their interests go well beyond increasing pay and benefits. A local union president has found that his members are best served by participating in a community-wide coalition. Providing eyeglasses to needy students, promoting healthy eating, and increasing…

  2. Repartnering after First Union Disruption

    ERIC Educational Resources Information Center

    Wu, Zheng; Schimmele, Christoph M.

    2005-01-01

    Using data from the 1995 General Social Survey (N= 2,639), this study examines two competing repartnering choices made by Canadians after first union disruption: marriage or cohabitation. About 42% of women and 54% of men form a second union 5 years after union disruption, with cohabitation being the most prevalent choice. The timing of second…

  3. Rényi squashed entanglement, discord, and relative entropy differences

    NASA Astrophysics Data System (ADS)

    Seshadreesan, Kaushik P.; Berta, Mario; Wilde, Mark M.

    2015-10-01

    The squashed entanglement quantifies the amount of entanglement in a bipartite quantum state, and it satisfies all of the axioms desired for an entanglement measure. The quantum discord is a measure of quantum correlations that are different from those due to entanglement. What these two measures have in common is that they are both based upon the conditional quantum mutual information. In Berta et al (2015 J. Math. Phys. 56 022205), we recently proposed Rényi generalizations of the conditional quantum mutual information of a tripartite state on ABC (with C being the conditioning system), which were shown to satisfy some properties that hold for the original quantity, such as non-negativity, duality, and monotonicity with respect to local operations on the system B (with it being left open to show that the Rényi quantity is monotone with respect to local operations on system A). Here we define a Rényi squashed entanglement and a Rényi quantum discord based on a Rényi conditional quantum mutual information and investigate these quantities in detail. Taking as a conjecture that the Rényi conditional quantum mutual information is monotone with respect to local operations on both systems A and B, we prove that the Rényi squashed entanglement and the Rényi quantum discord satisfy many of the properties of the respective original von Neumann entropy based quantities. In our prior work (Berta et al 2015 Phys. Rev. A 91 022333), we also detailed a procedure to obtain Rényi generalizations of any quantum information measure that is equal to a linear combination of von Neumann entropies with coefficients chosen from the set \\{-1,0,1\\}. Here, we extend this procedure to include differences of relative entropies. Using the extended procedure and a conjectured monotonicity of the Rényi generalizations in the Rényi parameter, we discuss potential remainder terms for well known inequalities such as monotonicity of the relative entropy, joint convexity of the relative

  4. Geometric quantum discord and non-Markovianity of structured reservoirs

    NASA Astrophysics Data System (ADS)

    Hu, Ming-Liang; Lian, Han-Li

    2015-11-01

    The reservoir memory effects can lead to information backflow and recurrence of the previously lost quantum correlations. We establish connections between the direction of information flow and variation of the geometric quantum discords (GQDs) measured respectively by the trace distance, the Hellinger distance, and the Bures distance for two qubits subjecting to the bosonic structured reservoirs, and unveil their dependence on a factor whose derivative signifies the (non-)Markovianity of the dynamics. By considering the reservoirs with Lorentzian and Ohmic-like spectra, we further demonstrated that the non-Markovianity induced by the backflow of information from the reservoirs to the system enhances the GQDs in most of the parameter regions. This highlights the potential of non-Markovianity as a resource for protecting the GQDs.

  5. Two monozygotic (identical) twin pairs discordant for gender identity.

    PubMed

    Green, R; Stoller, R J

    1971-12-01

    Two pairs of monozygotic twins discordant for gender identity are described. The first set are 8-year-old males, one of whom enjoys doll play, cross-dressing, and taking the role of a female in fantasy games. His brother shows no feminine behavior, enjoys sports, and is more masculine in gestures and speech. The second set are 24-year-old females, one of whom wants to undergo sex-change surgery to male status. Her cotwin is a feminine woman desirous of marrying and bearing children. Differential childhood experiences are described for the cotwins. These highlight environmental influences, which may contribute to variances in masculinity and femininity, when genetic influences are held relatively constant. PMID:24179079

  6. The inheritance of neuropsychological dysfunction in twins discordant for schizophrenia.

    PubMed

    Cannon, T D; Huttunen, M O; Lonnqvist, J; Tuulio-Henriksson, A; Pirkola, T; Glahn, D; Finkelstein, J; Hietanen, M; Kaprio, J; Koskenvuo, M

    2000-08-01

    While genetic influences in schizophrenia are substantial, the disorder's molecular genetic basis remains elusive. Progress has been hindered by lack of means to detect nonpenetrant carriers of the predisposing genes and by uncertainties concerning the extent of locus heterogeneity. One approach to solving this complexity is to examine the inheritance of pathophysiological processes mediating between genotype and disease phenotype. Here we evaluate whether deficits in neurocognitive functioning covary with degree of genetic relationship with a proband in the unaffected MZ and DZ co-twins of patients with schizophrenia. Twin pairs discordant for schizophrenia were recruited from a total population cohort and were compared with a demographically balanced sample of control twin pairs, on a comprehensive neuropsychological test battery. The following four neuropsychological functions contributed uniquely to the discrimination of degree of genetic loading for schizophrenia and, when combined, were more highly correlated within MZ pairs than within DZ pairs, in both discordant and control twins: spatial working memory (i.e., remembering a sequence of spatial locations over a brief delay), divided attention (i.e., simultaneous performance of a counting and visual-search task), intrusions during recall of a word list (i.e., "remembering" nonlist items), and choice reaction time to visual targets. Together with evidence from human and animal studies of mediation of these functions by partially distinct brain systems, our findings suggest that there are multiple independently inherited dimensions of neural deficit in schizophrenia and encourage a search for genes contributing to quantitative variation in discrete aspects of disease liability. On tests of verbal and visual episodic memory, but not on the liability-related measures, patients were more impaired than their own MZ co-twins, suggesting a preferential impact of nongenetic influences on long-term memory systems

  7. EPICE-HIV: An Epidemiologic Cost-Effectiveness Model for HIV Treatment

    PubMed Central

    Vandewalle, Björn; Llibre, Josep M.; Parienti, Jean-Jacques; Ustianowski, Andrew; Camacho, Ricardo; Smith, Colette; Miners, Alec; Ferreira, Diana; Félix, Jorge

    2016-01-01

    The goal of this research was to establish a new and innovative framework for cost-effectiveness modeling of HIV-1 treatment, simultaneously considering both clinical and epidemiological outcomes. EPICE-HIV is a multi-paradigm model based on a within-host micro-simulation model for the disease progression of HIV-1 infected individuals and an agent-based sexual contact network (SCN) model for the transmission of HIV-1 infection. It includes HIV-1 viral dynamics, CD4+ T cell infection rates, and pharmacokinetics/pharmacodynamics modeling. Disease progression of HIV-1 infected individuals is driven by the interdependent changes in CD4+ T cell count, changes in plasma HIV-1 RNA, accumulation of resistance mutations and adherence to treatment. The two parts of the model are joined through a per-sexual-act and viral load dependent probability of disease transmission in HIV-discordant couples. Internal validity of the disease progression part of the model is assessed and external validity is demonstrated in comparison to the outcomes observed in the STaR randomized controlled clinical trial. We found that overall adherence to treatment and the resulting pattern of treatment interruptions are key drivers of HIV-1 treatment outcomes. Our model, though largely independent of efficacy data from RCT, was accurate in producing 96-week outcomes, qualitatively and quantitatively comparable to the ones observed in the STaR trial. We demonstrate that multi-paradigm micro-simulation modeling is a promising tool to generate evidence about optimal policy strategies in HIV-1 treatment, including treatment efficacy, HIV-1 transmission, and cost-effectiveness analysis. PMID:26870960

  8. EPICE-HIV: An Epidemiologic Cost-Effectiveness Model for HIV Treatment.

    PubMed

    Vandewalle, Björn; Llibre, Josep M; Parienti, Jean-Jacques; Ustianowski, Andrew; Camacho, Ricardo; Smith, Colette; Miners, Alec; Ferreira, Diana; Félix, Jorge

    2016-01-01

    The goal of this research was to establish a new and innovative framework for cost-effectiveness modeling of HIV-1 treatment, simultaneously considering both clinical and epidemiological outcomes. EPICE-HIV is a multi-paradigm model based on a within-host micro-simulation model for the disease progression of HIV-1 infected individuals and an agent-based sexual contact network (SCN) model for the transmission of HIV-1 infection. It includes HIV-1 viral dynamics, CD4+ T cell infection rates, and pharmacokinetics/pharmacodynamics modeling. Disease progression of HIV-1 infected individuals is driven by the interdependent changes in CD4+ T cell count, changes in plasma HIV-1 RNA, accumulation of resistance mutations and adherence to treatment. The two parts of the model are joined through a per-sexual-act and viral load dependent probability of disease transmission in HIV-discordant couples. Internal validity of the disease progression part of the model is assessed and external validity is demonstrated in comparison to the outcomes observed in the STaR randomized controlled clinical trial. We found that overall adherence to treatment and the resulting pattern of treatment interruptions are key drivers of HIV-1 treatment outcomes. Our model, though largely independent of efficacy data from RCT, was accurate in producing 96-week outcomes, qualitatively and quantitatively comparable to the ones observed in the STaR trial. We demonstrate that multi-paradigm micro-simulation modeling is a promising tool to generate evidence about optimal policy strategies in HIV-1 treatment, including treatment efficacy, HIV-1 transmission, and cost-effectiveness analysis. PMID:26870960

  9. HIV / AIDS and the law.

    PubMed

    1997-09-01

    Since HIV is sexually transmitted, people living with AIDS and HIV (PWA/PHA) risk being stigmatized as immoral and promiscuous and they are often discriminated against in society. To this effect, the South African AIDS Law Project and Lawyers for Human Rights have developed a comprehensive resource manual detailing human rights with a special emphasis on issues relevant to PWA/PHA. The concept of the manual aimed to look at the legal and human rights questions that have been raised by the HIV/AIDS epidemic; inform people living with HIV/AIDS about their rights and the law; provide people working in businesses, trade unions, and nongovernmental organization with information about correct and incorrect responses to HIV/AIDS; and give victims of discrimination ideas on how to fight back. This manual initially introduces basic facts about HIV and AIDS and then describes the legal system and the Bill of Rights within the new South African Constitution. The main areas of focus in the manual include: 1) patient's medical rights, 2) employment rights, 3) women's rights, 4) the rights of lesbians and gay men, 5) the rights of youth and children, 6) the rights of prisoners, 7) social support for PWA, 8) HIV/AIDS and insurance law, 9) power of attorney and making wills, 10) criminal law, and 11) legal remedies, such as using the law to protect one's rights. PMID:12222382

  10. Effect of Spin-Orbit Interaction and Input State on Quantum Discord and Teleportation of Two-Qubit Heisenberg Systems

    NASA Astrophysics Data System (ADS)

    Qin, Meng; Zhai, Xiao-Yue; Chen, Xuan; Li, Yan-Biao; Wang, Xiao; Bai, Zhong

    2012-03-01

    We study the quantum discord and teleportation of a two-qubit Heisenberg XXX chain with spin-orbit interaction. The analytical expressions of quantum discord, output state quantum discord and fidelity are obtained for this model. The classical correlation, quantum correlation and entanglement of this system depending on coupling interaction, spin-orbit interaction and temperature are investigated in detail. It is found that the quantum discord exists for the ferromagnetic case, but entanglement is zero under the same condition. We can obtain fidelity better than any classical communication protocol for the antiferromagnetic case. The robustness of quantum discord against the temperature is helpful for the realization of quantum computation.

  11. Couple-level Motivations to Test for HIV for Gay Men in Relationships

    PubMed Central

    Beougher, Sean C.; Bircher, Anja E.; Chakravarty, Deepalika; Darbes, Lynae A.; Gómez Mandic, Carmen; Neilands, Torsten B.; Garcia, Carla C.; Hoff, Colleen C.

    2015-01-01

    Previous studies of HIV testing among gay men describe the motivations, facilitators and barriers, behaviors, and demographic characteristics of individuals who test. What little research focuses on HIV testing among gay men in relationships shows that they do not test regularly or, in some cases, at all – their motivations to test have not been investigated. With so little data on HIV testing for this population, and the continued privileging of individually-focused approaches, gay men in relationships fall into a blind spot of research and prevention efforts. This study examined motivations to test for HIV using qualitative data from both partners in 20 gay male couples. Analysis revealed that the partners’ motivations were either event-related (e.g., participants testing the beginning of their relationship or HIV-negative participants in an HIV-discordant relationship testing after risky episode with their discordant primary partner) or partner-related (e.g., participants testing in response to a request or suggestion to test from their primary partner or participants testing out of concern for their primary partner’s health and wellbeing). These data provide insight into relationship-oriented motivations to test for HIV for gay men in relationships and, in doing so, demonstrates their commitment to their primary partner and relationship. These motivations can be leveraged to increase HIV testing among gay men in relationships, a population that tests less often than single gay men, yet, until recently, has been underserved by prevention efforts. PMID:25550145

  12. Environmental Factors in Obsessive-Compulsive Behavior: Evidence from Discordant and Concordant Monozygotic Twins

    PubMed Central

    van Grootheest, Daniel S.; Willemsen, Gonneke; van Oppen, Patricia; Boomsma, Dorret I.

    2008-01-01

    To investigate environmental factors that protect against or exacerbate obsessive-compulsive (OC) symptoms, we selected 25 monozygotic (MZ) twin pairs discordant, 17 MZ twin pairs concordant high and 34 MZ pairs concordant low on OC symptoms from a large longitudinal Dutch sample of adult twin pairs and their family members, applying stringent criteria for OC symptomatology. Data were collected on psychopathology, family structure, health, lifestyle, birth complications and life events. Unique environmental factors were studied using within-discordant MZ pair comparisons, whereas between-concordant MZ pair comparisons were used to study environmental factors that are shared by the twins of an MZ pair. The high-scoring MZ twins of the discordant group reported more life events (especially sexual abuse) than their low-scoring twin-siblings. The between-pair comparisons showed lower birth weight in the discordant MZ pairs than in the concordant MZ pairs. Further, the concordant high MZ pairs as well as their spouses had a lower educational level than the two other groups. On scale scores of anxious-depression, neuroticism, and somatic complaints, concordant high MZ pairs showed highest scores, and the discordant MZ pairs scored intermediate, except for neuroticism, on which the high-scoring twins of discordant MZ pairs were equal to the concordant high pairs. Discordance on psychological scale scores between the concordant MZ pairs was evident from 1991 onward, and within the discordant MZ pairs from 1997 onward, confirming previous reports of an association of early-onset OC symptoms with higher genetic load. Parent scores of OC symptoms and anxious-depression suggested intermediate genetic load in the discordant MZ group. In conclusion, this study reports on both unique and shared environmental factors associated with OC symptomatology. Whether these factors operate in addition to or in interaction with genetic disposition is to be elucidated in future studies

  13. Antiviral agents and HIV prevention: controversies, conflicts, and consensus

    PubMed Central

    Cohen, Myron S.; Muessig, Kathryn E.; Smith, M. Kumi; Powers, Kimberly A.; Kashuba, Angela D.M.

    2013-01-01

    Antiviral agents can be used to prevent HIV transmission before exposure as preexpo-sure prophylaxis (PrEP), after exposure as postexposure prophylaxis, and as treatment of infected people for secondary prevention. Considerable research has shed new light on antiviral agents for PrEP and for prevention of secondary HIV transmission. While promising results have emerged from several PrEP trials, the challenges of poor adherence among HIV-negative clients and possible increase in sexual risk behaviors remain a concern. In addition, a broader pipeline of antiviral agents for PrEP that focuses on genital tract pharmacology and safety and resistance issues must be developed. Antiretroviral drugs have also been used to prevent HIV transmission from HIV-infected patients to their HIV-discordant sexual partners. The HIV Prevention Trials Network 052 trial demonstrated nearly complete prevention of HIV transmission by early treatment of infection, but the generalizability of the results to other risk groups – including intravenous drug users and MSM – has not been determined. Most importantly, the best strategy for use of antiretroviral agents to reduce the spread of HIV at either the individual level or the population level has not been developed, and remains the ultimate goal of this area of investigation. PMID:22507927

  14. Entanglement and discord of the superposition of Greenberger-Horne-Zeilinger states

    SciTech Connect

    Parashar, Preeti; Rana, Swapan

    2011-03-15

    We calculate the analytic expression for geometric measure of entanglement for arbitrary superposition of two N-qubit canonical orthonormal Greenberger-Horne-Zeilinger (GHZ) states and the same for two W states. In the course of characterizing all kinds of nonclassical correlations, an explicit formula for quantum discord (via relative entropy) for the former class of states has been presented. Contrary to the GHZ state, the closest separable state to the W state is not classical. Therefore, in this case, the discord is different from the relative entropy of entanglement. We conjecture that the discord for the N-qubit W state is log{sub 2}N.

  15. Geometric measure of pairwise quantum discord for superpositions of multipartite generalized coherent states

    NASA Astrophysics Data System (ADS)

    Daoud, M.; Ahl Laamara, R.

    2012-07-01

    We give the explicit expressions of the pairwise quantum correlations present in superpositions of multipartite coherent states. A special attention is devoted to the evaluation of the geometric quantum discord. The dynamics of quantum correlations under a dephasing channel is analyzed. A comparison of geometric measure of quantum discord with that of concurrence shows that quantum discord in multipartite coherent states is more resilient to dissipative environments than is quantum entanglement. To illustrate our results, we consider some special superpositions of Weyl-Heisenberg, SU(2) and SU(1,1) coherent states which interpolate between Werner and Greenberger-Horne-Zeilinger states.

  16. Hierarchy of Efficiently Computable and Faithful Lower Bounds to Quantum Discord

    NASA Astrophysics Data System (ADS)

    Piani, Marco

    2016-08-01

    Quantum discord expresses a fundamental nonclassicality of correlations that is more general than entanglement, but that, in its standard definition, is not easily evaluated. We derive a hierarchy of computationally efficient lower bounds to the standard quantum discord. Every nontrivial element of the hierarchy constitutes by itself a valid discordlike measure, based on a fundamental feature of quantum correlations: their lack of shareability. Our approach emphasizes how the difference between entanglement and discord depends on whether shareability is intended as a static property or as a dynamical process.

  17. Hierarchy of Efficiently Computable and Faithful Lower Bounds to Quantum Discord.

    PubMed

    Piani, Marco

    2016-08-19

    Quantum discord expresses a fundamental nonclassicality of correlations that is more general than entanglement, but that, in its standard definition, is not easily evaluated. We derive a hierarchy of computationally efficient lower bounds to the standard quantum discord. Every nontrivial element of the hierarchy constitutes by itself a valid discordlike measure, based on a fundamental feature of quantum correlations: their lack of shareability. Our approach emphasizes how the difference between entanglement and discord depends on whether shareability is intended as a static property or as a dynamical process. PMID:27588837

  18. Development of AACAP practice parameters for gender nonconformity and gender discordance in children and adolescents.

    PubMed

    Adelson, Stewart L

    2011-10-01

    The American Academy of Child and Adolescent Psychiatry (AACAP) is preparing a publication, Practice Parameter on Gay, Lesbian or Bisexual Sexual Orientation, Gender-Nonconformity, and Gender Discordance in Children and Adolescents. This article discusses the development of the part of the parameter related to gender nonconformity and gender discordance and describes the practice parameter preparation process,rationale, key scientific evidence, and methodology. Also discussed are terminology considerations, related clinical issues and practice skills, and overall organization of information including influences on gender development, gender role behavior, gender nonconformity and gender discordance, and their relationship to the development of sexual orientation. PMID:22051003

  19. Women and HIV

    MedlinePlus

    ... Consumer Information by Audience For Women Women and HIV Share Tweet Linkedin Pin it More sharing options ... HIV? What should pregnant women know about HIV? HIV Quick Facts What is HIV? HIV is the ...

  20. Perceived HIV status is a key determinant of unprotected anal intercourse within partnerships of men who have sex with men in Amsterdam.

    PubMed

    Matser, Amy; Heijman, Titia; Geskus, Ronald; de Vries, Henry; Kretzschmar, Mirjam; Speksnijder, Arjen; Xiridou, Maria; Fennema, Han; Schim van der Loeff, Maarten

    2014-12-01

    The practice of unprotected anal intercourse (UAI) involves at least two partners. We examined the associations between insertive or receptive UAI and perceived HIV seroconcordance and partnership type in self-perceived HIV-negative and self-perceived HIV-positive men who have sex with men (MSM). MSM (age ≥ 18 years) were recruited for a cross-sectional survey at the sexually transmitted infections clinic in Amsterdam, the Netherlands, in 2008-2009. Participants completed a questionnaire concerning partnerships in the preceding 6 months. Associations were quantified via multinomial logistic regression models using generalized estimating equations. The outcomes were 'no, or safe anal intercourse', 'insertive UAI', and 'receptive UAI'. We included 5,456 partnerships from 1,890 self-perceived HIV-negative men and 1,861 partnerships from 558 self-perceived HIV-positive men. Within the partnerships, perceived HIV status of the partner was an important determinant of UAI (p < 0.001). Among HIV-negative men, perceived HIV discordance was negatively associated with receptive UAI compared with no or safe UAI (OR 0.57; 95 % CI 0.36-0.92); when the partners were more familiar with each other, the risk of receptive UAI was increased relative to no or safe anal intercourse. Among HIV-positive men, perceived HIV discordance was negatively associated with insertive UAI (OR 0.05; 95 % CI 0.03-0.08). Within partnerships, perceived HIV status of the partner was one of the strongest determinants of UAI among self-perceived HIV-negative and HIV-positive MSM, and discordant serostatus was negatively associated with UAI. The findings suggest that serosorting is one of the main strategies when engaging in UAI. PMID:24920343

  1. Risk of Anal Cancer in People Living with HIV: Addressing Anal Health in the HIV Primary Care Setting.

    PubMed

    Walker, Crystal Martin; Likes, Wendy; Bernard, Marye; Kedia, Satish; Tolley, Elizabeth

    2016-01-01

    Anal health and anal cancer are rarely addressed in HIV primary care. We sought to understand factors that impeded or promoted addressing anal health in HIV primary care from providers' perspectives. In this exploratory study, HIV primary care providers from the Mid-South region of the United States participated in brief individual interviews. We analyzed transcribed data to identify barriers and facilitators to addressing anal health. Our study sample included five physicians and four nurse practitioners. The data revealed a number of barriers such as perception of patient embarrassment, provider embarrassment, external issues such as time constraints, demand of other priorities, lack of anal complaints, lack of resources, and gender discordance. Facilitators included awareness, advantageous circumstances, and the patient-provider relationship. Anal health education should be prioritized for HIV primary care providers. Preventive health visits should be considered to mitigate time constraints, demands for other priorities, and unequal gender opportunities. PMID:27080925

  2. Union Density and Hospital Outcomes.

    PubMed

    Koys, Daniel J; Martin, Wm Marty; LaVan, Helen; Katz, Marsha

    2015-01-01

    The authors address the hospital outcomes of patient satisfaction, healthcare quality, and net income per bed. They define union density as the percentage of a hospital's employees who are in unions, healthcare quality as its 30-day acute myocardial infraction (AMI; heart attack) mortality rate, and patient satisfaction as its overall Hospital Consumer Assessment of Healthcare Providers and Systems score. Using a random sample of 84 union and 84 nonunion hospitals from across the United States, multiple regression analyses show that union density is negatively related to patient satisfaction. Union density is not related to healthcare quality as measured by the AMI mortality rate or to net income per bed. This implies that unions per se are not good or bad for hospitals. The authors suggest that it is better for hospital administrators to take a Balanced Scorecard approach and be concerned about employee satisfaction, patient satisfaction, healthcare quality, and net income. PMID:26652043

  3. The relation between the quantum discord and quantum teleportation: The physical interpretation of the transition point between different quantum discord decay regimes

    NASA Astrophysics Data System (ADS)

    Roszak, K.; Cywiński, Ł.

    2015-10-01

    We study quantum teleportation via Bell-diagonal mixed states of two qubits in the context of the intrinsic properties of the quantum discord. We show that when the quantum-correlated state of the two qubits is used for quantum teleportation, the character of the teleportation efficiency changes substantially depending on the Bell-diagonal-state parameters, which can be seen when the worst-case-scenario or best-case-scenario fidelity is studied. Depending on the parameter range, one of two types of single-qubit states is hardest/easiest to teleport. The transition between these two parameter ranges coincides exactly with the transition between the range of classical correlation decay and quantum correlation decay characteristic for the evolution of the quantum discord. The correspondence provides a physical interpretation for the prominent feature of the decay of the quantum discord.

  4. Geometric quantum discord of a Jaynes-Cummings atom and an isolated atom

    NASA Astrophysics Data System (ADS)

    Qiang, Wen-Chao; Zhang, Lei; Zhang, Hua-Ping

    2015-12-01

    We studied the geometric quantum discord of a quantum system consisting of a Jaynes-Cummings (JC) atom, a cavity and an isolated atom. The analytical expressions of the geometric quantum discord for two atoms, every atom with a cavity and the total system were obtained. We showed that the geometric quantum discord is not always zero when the entanglement falls to zero for a two-atom subsystem; the geometric measurement of the quantum discord of the total system developed periodically with a single frequency if the initial two-atom state was not entangled, otherwise, it oscillated with two or four frequencies according to whether the cavity was initially empty or not, respectively.

  5. A note on one-way quantum deficit and quantum discord

    NASA Astrophysics Data System (ADS)

    Ye, Biao-Liang; Fei, Shao-Ming

    2016-01-01

    One-way quantum deficit and quantum discord are two important measures of quantum correlations. We revisit the relationship between them in two-qubit systems. We investigate the conditions that both one-way quantum deficit and quantum discord have the same optimal measurement ensembles, and demonstrate that one-way quantum deficit can be derived from the quantum discord for a class of X states. Moreover, we give an explicit relation between one-way quantum deficit and entanglement of formation. We show that under phase damping channel both one-way quantum deficit and quantum discord evolve exactly in the same way for four parameter X states. Some examples are presented in details.

  6. Quantum discord and entanglement of two atoms in a micromaser-type system

    NASA Astrophysics Data System (ADS)

    Yan, Xue-Qun; Wang, Fu-Zhong

    2016-06-01

    The correlations dynamics of two atoms in the case of a micromaser-type system is investigated. We show that the entangled state can be created by initially maximally mixed state and there exist collapse and revival phenomena for the time evolutions of both entanglement and quantum discord under the system considered as the field is initially in the Fock state. Our results confirm that entanglement and quantum discord have similar behaviors in certain time ranges, such as their oscillations during the time evolution being almost in phase, but they also present significant differences, such as quantum discord being maintained even after the complete loss of entanglement. Furthermore, we exhibit clearly that the dynamics of quantum discord under the action of environment are intimately related to the generation and evolution of entanglement.

  7. Gaussian geometric discord of two-mode systems in a thermal environment

    SciTech Connect

    Suciu, Serban Isar, Aurelian

    2014-11-24

    In the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we give a description of the Gaussian geometric discord for a system consisting of two non-interacting non-resonant bosonic modes embedded in a thermal environment. We take as initial state of the system a two-mode squeezed thermal state and describe the time evolution of the Gaussian geometric discord under the influence of the thermal bath. By tracing the distance between the state of the considered subsystem and the closest classical-quantum Gaussian state we evaluate the Gaussian geometric discord for all times and temperatures. The geometric discord has finite values between 0 and 1 and decreases asymptotically to zero at large times and temperatures with oscillations on the time axis.

  8. Comparison of different measures for quantum discord under non-Markovian noise

    NASA Astrophysics Data System (ADS)

    Xu, Z. Y.; Yang, W. L.; Xiao, X.; Feng, M.

    2011-09-01

    Two geometric measures for quantum discord were recently proposed by Modi et al (2010 Phys. Rev. Lett.104 080501) and Dakić et al (2010 Phys. Rev. Lett.105 190502). We study the similarities and differences for total quantum correlations of Bell-diagonal states using these two geometry-based quantum discord and the original quantum discord. We show that, under non-Markovian dephasing channels, quantum discord and one of the geometric measures remain constant for a finite amount of time, but not the other geometric measure. However, all the three measures share a common sudden change point. Our study on critical point of sudden transition might be useful for keeping long-time total quantum correlations under decoherence.

  9. Geometric measure of quantum discord for entanglement of Dirac fields in noninertial frames

    NASA Astrophysics Data System (ADS)

    Qiang, Wen-Chao; Zhang, Lei

    2015-03-01

    We investigate the geometric measure of quantum discord of all possible bipartite divisions of a tripartite system of Dirac fields in noninertial frames. As a comparison, we calculate the geometric measure of entanglement. We discuss the properties of geometric measure of quantum discord and geometric measure of entanglement for three qubit-qubit subsystems with acceleration parameter and the parameter describing the degree of entanglement the system in detail. We have found a conservative relationship involving two of three geometric discords in some condition and another conservative relationship involving three geometric discords for initially maximally entangled states. By the way, we also report some conservative relationships of concurrence, mutual information and geometric measure of entanglement for two bipartite subsystems.

  10. Double sudden transitions of geometric discord at finite-temperature in the framework of stochastic description

    SciTech Connect

    Wu, Wei; Luo, Da-Wei; Xu, Jing-Bo

    2014-06-28

    We investigate the phenomenon of double sudden transitions in geometric quantum correlations for a system consisting of a bare qubit and a qubit locally coupled to its finite-temperature heat environment with an Ohmic spectrum in the framework of stochastic description. Moreover, we explore the possibility of protecting the geometric discord between the two qubits and prolonging the time during which the geometric discord remains constant by applying Bang-Bang pulses.

  11. What predicts intention-behavior discordance? A review of the action control framework.

    PubMed

    Rhodes, Ryan E; de Bruijn, Gert-Jan

    2013-10-01

    The physical activity intention-behavior gap is a focus of considerable research. The purpose of this article is to overview contemporary evidence for predictors of this intention-behavior discordance using the action control framework developed in our laboratories. We propose the hypothesis that intention-behavior discordance is from motivational (affective attitude, perceived behavioral control), self-regulatory (behavioral processes), and habitual (automaticity) constructs. PMID:23873134

  12. Hilbert-Schmidt Measure of Pairwise Quantum Discord for Three-Qubit X States

    NASA Astrophysics Data System (ADS)

    Daoud, M.; Laamara, R. Ahl; Seddik, S.

    2015-10-01

    The Hilbert-Schmidt distance between a mixed three-qubit state and its closest state is used to quantify the amount of pairwise quantum correlations in a tripartite system. Analytical expressions of geometric quantum discord are derived. A particular attention is devoted to two special classes of three-qubit X states. They include three-qubit states of W, GHZ and Bell type. We also discuss the monogamy property of geometric quantum discord in some mixed three-qubit systems.

  13. Quantum Discord in Photon-Added Glauber Coherent States of GHZ-Type

    NASA Astrophysics Data System (ADS)

    Daoud, M.; Kaydi, W.; El Hadfi, H.

    2015-11-01

    We investigate the influence of photon excitations on quantum correlations in tripartite Glauber coherent states of Greenberger-Horne-Zeilinger type (GHZ-type). The pairwise correlations are measured by means of the entropy-based quantum discord. We also analyze the monogamy property of quantum discord in this class of tripartite states in terms of the strength of Glauber coherent states and the photon excitation order.

  14. Peer Review of Grant Applications: A Simple Method to Identify Proposals with Discordant Reviews

    PubMed Central

    Giraudeau, Bruno; Leyrat, Clémence; Le Gouge, Amélie; Léger, Julie; Caille, Agnès

    2011-01-01

    Grant proposals submitted for funding are usually selected by a peer-review rating process. Some proposals may result in discordant peer-review ratings and therefore require discussion by the selection committee members. The issue is which peer-review ratings are considered as discordant. We propose a simple method to identify such proposals. Our approach is based on the intraclass correlation coefficient, which is usually used in assessing agreement in studies with continuous ratings. PMID:22110670

  15. Dynamics of entanglement and quantum discord in the Tavis–Cummings model

    NASA Astrophysics Data System (ADS)

    Restrepo, Juliana; Rodríguez, Boris A.

    2016-06-01

    We revisit the problem of the dynamics of quantum correlations in the Tavis–Cummings model. Our results show that the dynamics of entanglement and quantum discord are far from being trivial or intuitive. We find states with the same entanglement but different discord and states where the two quantifiers give opposite information about correlations at a certain time. We furthermore show that many of the dynamical features of quantum discord attributed to dissipation are already present in the exact framework and are due to the characteristic quantum nonlinearity of the model and to the choice of initial conditions. Through a comprehensive analysis of pure and mixed initial conditions, we find a fascinating range of phenomena that can be used for experimental purposes. We propose an experiment called quantum discord gates where for a given pure initial condition discord is zero or non-zero depending on the number of photons in the cavity. Given the marginal character of states with zero discord this result is not only completely counterintuitive but is also useful as a way to count photons.

  16. Non-local correlation and quantum discord in two atoms in the non-degenerate model

    SciTech Connect

    Mohamed, A.-B.A.

    2012-12-15

    By using geometric quantum discord (GQD) and measurement-induced nonlocality (MIN), quantum correlation is investigated for two atoms in the non-degenerate two-photon Tavis-Cummings model. It is shown that there is no asymptotic decay for MIN while asymptotic decay exists for GQD. Quantum correlations can be strengthened by introducing the dipole-dipole interaction. The evolvement period of quantum correlation gets shorter with the increase in the dipole-dipole parameter. It is found that there exists not only quantum nonlocality without entanglement but also quantum nonlocality without quantum discord. Also, the MIN and GQD are raised rather than entanglement, and also with weak initial entanglement, there are MIN and entanglement in a interval of death quantum discord. - Highlights: Black-Right-Pointing-Pointer Geometric quantum discord (GQD) and measurement induced nonlocality (MIN) are used to investigate the correlations of two two-level atoms. Black-Right-Pointing-Pointer There is no asymptotic decay for MIN while asymptotic decay exists for GQD. Black-Right-Pointing-Pointer Quantum correlations can be strengthened by introducing the dipole-dipole interaction. Black-Right-Pointing-Pointer There exists not only quantum nonlocality without entanglement but also without discord. Black-Right-Pointing-Pointer Weak initial entanglement leads to MIN and entanglement in intervals of death discord.

  17. Cough Aerosol Cultures of Mycobacterium tuberculosis: Insights on TST / IGRA Discordance and Transmission Dynamics

    PubMed Central

    Jones-López, Edward C.; White, Laura F.; Kirenga, Bruce; Mumbowa, Francis; Ssebidandi, Martin; Moine, Stephanie; Mbabazi, Olive; Mboowa, Gerald; Ayakaka, Irene; Kim, Soyeon; Thornton, Christina S.; Okwera, Alphonse; Joloba, Moses; Fennelly, Kevin P.

    2015-01-01

    Rationale The diagnosis of latent tuberculosis (TB) infection (LTBI) is complicated by the absence of a gold standard. Discordance between tuberculin skin tests (TST) and interferon gamma release assays (IGRA) occurs in 10–20% of individuals, but the underlying mechanisms are poorly understood. Methods We analyzed data from a prospective household contact study that included cough aerosol culture results from index cases, environmental and contact factors. We assessed contacts for LTBI using TST and IGRA at baseline and six weeks. We examined TST/IGRA discordance in qualitative and quantitative analyses, and used multivariable logistic regression analysis with generalized estimating equations to analyze predictors of discordance. Measurements and Results We included 96 TB patients and 384 contacts. Discordance decreased from 15% at baseline to 8% by six weeks. In adjusted analyses, discordance was related to less crowding (p = 0.004), non-cavitary disease (OR 1.41, 95% CI: 1.02–1.96; p = 0.03), and marginally with BCG vaccination in contacts (OR 1.40, 95% CI: 0.99–1.98, p = 0.06). Conclusions We observed significant individual variability and temporal dynamism in TST and IGRA results in household contacts of pulmonary TB cases. Discordance was associated with a less intense infectious exposure, and marginally associated with a BCG-mediated delay in IGRA conversion. Cough aerosols provide an additional dimension to the assessment of infectiousness and risk of infection in contacts. PMID:26394149

  18. Discordant introgression in a rapidly expanding hybrid swarm

    USGS Publications Warehouse

    Ward, Jessica L.; Blum, Mike J.; Walters, David M.; Porter, Brady A.; Burkhead, Noel; Freeman, Byron

    2012-01-01

    The erosion of species boundaries can involve rapid evolutionary change. Consequently, many aspects of the process remain poorly understood, including the formation, expansion, and evolution of hybrid swarms. Biological invasions involving hybridization present exceptional opportunities to study the erosion of species boundaries because timelines of interactions and outcomes are frequently well known. Here, we examined clinal variation across codominant and maternally inherited genetic markers as well as phenotypic traits to characterize the expansion and evolution of a hybrid swarm between native Cyprinella venusta and invasive Cyprinella lutrensis minnows. Discordant introgression of phenotype, microsatellite multilocus genotype, and mtDNA haplotype indicates that the observable expansion of the C. venusta x C. lutrensis hybrid swarm is a false invasion front. Both parental and hybrid individuals closely resembling C. lutrensis are numerically dominant in the expansion wake, indicating that the non-native parental phenotype may be selectively favored. These findings show that cryptic introgression can extend beyond the phenotypic boundaries of hybrid swarms and that hybrid swarms likely expand more rapidly than can be documented from phenotypic variation alone. Similarly, dominance of a single parental phenotype following an introduction event may lead to instances of species erosion being mistaken for species displacement without hybridization.

  19. Discordant introgression in a rapidly expanding hybrid swarm.

    PubMed

    Ward, Jessica L; Blum, Mike J; Walters, David M; Porter, Brady A; Burkhead, Noel; Freeman, Byron

    2012-06-01

    The erosion of species boundaries can involve rapid evolutionary change. Consequently, many aspects of the process remain poorly understood, including the formation, expansion, and evolution of hybrid swarms. Biological invasions involving hybridization present exceptional opportunities to study the erosion of species boundaries because timelines of interactions and outcomes are frequently well known. Here, we examined clinal variation across codominant and maternally inherited genetic markers as well as phenotypic traits to characterize the expansion and evolution of a hybrid swarm between native Cyprinella venusta and invasive Cyprinella lutrensis minnows. Discordant introgression of phenotype, microsatellite multilocus genotype, and mtDNA haplotype indicates that the observable expansion of the C. venusta × C. lutrensis hybrid swarm is a false invasion front. Both parental and hybrid individuals closely resembling C. lutrensis are numerically dominant in the expansion wake, indicating that the non-native parental phenotype may be selectively favored. These findings show that cryptic introgression can extend beyond the phenotypic boundaries of hybrid swarms and that hybrid swarms likely expand more rapidly than can be documented from phenotypic variation alone. Similarly, dominance of a single parental phenotype following an introduction event may lead to instances of species erosion being mistaken for species displacement without hybridization. PMID:25568058

  20. [Discordant growth in twin pregnancy--value of Doppler ultrasound].

    PubMed

    Grab, D; Hütter, W; Haller, T; Sterzik, K; Terinde, R

    1993-01-01

    A 4 MHz continuous-wave Doppler device was used to study uterine and umbilical arterial wave forms in 91 pairs of twins between 18th and 40th week of gestation. Biometry and cord localisation were effected by real-time ultrasound. The results of 182 Doppler flow examinations showed that umbilical flow velocimetry may prove relevant for early identification of twin pregnancies with discordant growth. Depending on the interval between examination and delivery, sensitivity and specificity values between 44% and 66%, and 66% and 73%, respectively, were obtained. A high resistance index in umbilical arteries was indicative of intrauterine growth retardation, at a specificity of 69% and a sensitivity of 44%. For uteroplacental as well as foetoplacental flow velocity waveform assessment, singleton reference values may be used, whereas, by reason of its low sensitivity, Doppler flow velocimetry does not lend itself as a primary diagnostic tool for intrauterine growth retardation. It can signal pathologic blood flow profiles, which are often associated with added risks, such as pregnancy-induced hypertension, foetal acidosis and stillbirth and can contribute to early detection of twin pregnancies that require close clinical and cardiotocographic surveillance. PMID:8440457

  1. Compositional discordance between prokaryotic plasmids and host chromosomes

    PubMed Central

    van Passel, Mark WJ; Bart, Aldert; Luyf, Angela CM; van Kampen, Antoine HC; van der Ende, Arie

    2006-01-01

    Background Most plasmids depend on the host replication machinery and possess partitioning genes. These properties confine plasmids to a limited range of hosts, yielding a close and presumably stable relationship between plasmid and host. Hence, it is anticipated that due to amelioration the dinucleotide composition of plasmids is similar to that of the genome of their hosts. However, plasmids are also thought to play a major role in horizontal gene transfer and thus are frequently exchanged between hosts, suggesting dinucleotide composition dissimilarity between plasmid and host genome. We compared the dinucleotide composition of a large collection of plasmids with that of their host genomes to shed more light on this enigma. Results The dinucleotide frequency, coined the genome signature, facilitates the identification of putative horizontally transferred DNA in complete genome sequences, since it was found to be typical for a certain genome, and similar between related species. By comparison of the genome signature of 230 plasmid sequences with that of the genome of each respective host, we found that in general the genome signature of plasmids is dissimilar from that of their host genome. Conclusion Our results show that the genome signature of plasmids does not resemble that of their host genome. This indicates either absence of amelioration or a less stable relationship between plasmids and their host. We propose an indiscriminate lifestyle for plasmids preserving the genome signature discordance between these episomes and host chromosomes. PMID:16480495

  2. Visuomotor discordance in virtual reality: effects on online motor control.

    PubMed

    Bagce, Hamid F; Saleh, Soha; Adamovich, Sergei V; Tunik, Eugene

    2011-01-01

    Virtual reality (VR) applications are rapidly permeating fields such as medicine, rehabilitation, research, and military training. However, VR-induced effects on human performance remain poorly understood, particularly in relation to fine-grained motor control of the hand and fingers. We designed a novel virtual reality environment suitable for hand-finger interactions and examined the ability to use visual feedback manipulations in VR to affect online motor performance. Ten healthy subjects performed a simple finger flexion movement toward a kinesthetically-defined 45° target angle while receiving one of three types of VR-based visual feedback in real-time: veridical (in which the virtual hand motion corresponded to subjects' actual motion), or scaled-down / scaled-up feedback (in which virtual finger motion was scaled by 25% / 175% relative to actual motion). Scaled down-and scaled-up feedback led to significant online modifications (increases and decreases, respectively) in angular excursion, despite explicit instructions for subjects to maintain constant movements across conditions. The latency of these modifications was similar across conditions. These findings demonstrate that a VR-based platform may be a robust medium for presenting visuomotor discordances to engender a sense of ownership and drive sensorimotor adaptation for (retraining motor skills. This may prove to be particularly important for retraining motor skills in patients with neurologically-based movement disorders. PMID:22256015

  3. Genotypic association analysis using discordant-relative-pairs.

    PubMed

    Yan, T; Yang, Y-N; Cheng, X; DeAngelis, M M; Hoh, J; Zhang, H

    2009-01-01

    In practice, family-based design has been widely used in disease-gene association analysis. The major advantage of such design is that it is not subject to spurious association due to population structure such as population stratification (PS) and admixture. A disadvantage is that parental genotypes are hard to obtain if the disease is late onset for which a discordant-relative-pair design is useful. Designs of such kind include full-sib-pair, half-sib-pair, first-cousin-pair, and so on. The closer the relatedness of the pair, the less possible that they are subject to population stratification. On the other hand, the association test using close relative-pairs may be less powerful due to over-matching. Trade-off between these two factors (population structure and over-matching) is the major concern of this study. Some tests, namely McNemar's test, matched Cochran-Armitage trend tests (CATTs), matched maximum efficient robust test (MERT), and Bhapkar's test, are used for testing disease-gene association based on relative-pair designs. These tests are shown to be valid in the presence of PS but not admixture. Numerical studies show that the McNemar's test, additive CATT, MERT, and Bhapkar's test are robust in power, but none of them is uniformly more powerful than the others. In most simulations, the power of any of the tests increases as the pair is more distant. The proposed methods are applied to two real examples. PMID:19040657

  4. Discordant phenotype in siblings with X-linked agammaglobulinemia

    SciTech Connect

    Bykowsky, M.J.; Veksler, K.S.; Sullivan, K.E.

    1996-03-01

    X-linked agammaglobulinemia (XLA) is a congenital humoral immunodeficiency caused by a defect in a B-cell-specific signaling molecule, Btk. There has been little concordance of phenotype with genotype in this disorder, and defects in Btk cause immunodeficiencies that range from mild impairment to complete inability to produce antibodies. The factors modifying the phenotype of XLA are not understood. The current study is the first description of two male siblings with identical T{sup 134}{yields}C mutations in the translation initiation ATG of Btk who have different clinical phenotypes as well as different laboratory phenotypes. The proband lacks immunoglobulins and B cells and has recurrent infections, while the elder, affected brother has normal levels of IgG and IgM and very few infections. Both have undetectable levels of Btk kinase activity in circulating mononuclear cells. Complete sequencing of Btk gene transcripts in both brothers revealed no additional mutations to account for the discordant phenotypes. This description provides unequivocal evidence that the phenotype of XLA is influenced by factors additional to the Btk gene. 39 refs., 3 figs., 3 tabs.

  5. [Discordant pattern, visual identification of myocardial viability with PET].

    PubMed

    Alexánderson, E; Ricalde, A; Zerón, J; Talayero, J A; Cruz, P; Adame, G; Mendoza, G; Meave, A

    2006-01-01

    PET (positron emission tomography) as a non-invasive imaging method for studying cardiac perfusion and metabolism has turned into the gold standard for detecting myocardial viability. The utilization of 18 FDG as a tracer for its identification permits to spot the use of exogenous glucose by the myocardium segments. By studying and comparing viability and perfusion results, for which the latter uses tracers such as 13N-ammonia, three different patterns for myocardial viability evaluation arise:. transmural concordant pattern, non-transmural concordant pattern, and the discordant pattern; the last one exemplifies the hibernating myocardium and proves the presence of myocardial viability. The importance of its detection is fundamental for the study of an ischemic patient, since it permits the establishment of and exact diagnosis, prognosis, and the best treatment option. It also allows foreseeing functional recovery of the affected region as well as the ejection fraction rate after revascularization treatment if this is determined as necessary. All these elements regarding viability are determinant in order to reduce adverse events and help improving patients' prognosis. PMID:17315610

  6. Quantum Discord Bounds the Amount of Distributed Entanglement

    NASA Astrophysics Data System (ADS)

    Piani, Marco; Kok Chuan, Tan; Maillard, Jean; Modi, Kavan; Paterek, Tomasz; Paternostro, Mauro

    2013-03-01

    The ability to distribute quantum entanglement is a prerequisite for many fundamental tests of quantum theory and numerous quantum information protocols. Two distant parties can increase the amount of entanglement between them by means of quantum communication encoded in a carrier that is sent from one party to the other. Intriguingly, entanglement can be increased even when the exchanged carrier is not entangled with the parties. However, in light of the defining property of entanglement stating that it cannot increase under classical communication, the carrier must be quantum. Here we show that, in general, the increase of relative entropy of entanglement between two remote parties is bounded by the amount of nonclassical correlations of the carrier with the parties as quantified by the relative entropy of discord. We study implications of this bound, provide new examples of entanglement distribution via unentangled states, and put further limits on this phenomenon. We thank the National Research Foundation and Ministry of Education in Singapore (T. K. Chuan, K. Modi, and T. Paterek), the John Templeton Foundation (K. Modi), the UK EPSRC (M. Paternostro), NSERC, CIFAR, and the Ontario Centres of Excellence (M. Piani)

  7. Exact solutions for species tree inference from discordant gene trees.

    PubMed

    Chang, Wen-Chieh; Górecki, Paweł; Eulenstein, Oliver

    2013-10-01

    Phylogenetic analysis has to overcome the grant challenge of inferring accurate species trees from evolutionary histories of gene families (gene trees) that are discordant with the species tree along whose branches they have evolved. Two well studied approaches to cope with this challenge are to solve either biologically informed gene tree parsimony (GTP) problems under gene duplication, gene loss, and deep coalescence, or the classic RF supertree problem that does not rely on any biological model. Despite the potential of these problems to infer credible species trees, they are NP-hard. Therefore, these problems are addressed by heuristics that typically lack any provable accuracy and precision. We describe fast dynamic programming algorithms that solve the GTP problems and the RF supertree problem exactly, and demonstrate that our algorithms can solve instances with data sets consisting of as many as 22 taxa. Extensions of our algorithms can also report the number of all optimal species trees, as well as the trees themselves. To better asses the quality of the resulting species trees that best fit the given gene trees, we also compute the worst case species trees, their numbers, and optimization score for each of the computational problems. Finally, we demonstrate the performance of our exact algorithms using empirical and simulated data sets, and analyze the quality of heuristic solutions for the studied problems by contrasting them with our exact solutions. PMID:24131054

  8. NOTE: Trends of discordant fetal growth in monochorionic twin pregnancies

    NASA Astrophysics Data System (ADS)

    van Gemert, Martin J. C.; Umur, Asli

    2000-08-01

    We derived simple analytical relations representing trends of discordant fetal growth in monochorionic twins developing the twin-twin transfusion syndrome from an approximation of previously developed model equations. In severe twin-twin transfusion syndrome cases, the difference between the estimated fetal weights of both twins increases proportional to (t-5)5 (t denotes gestational age in weeks) and the sum of both weights increases proportional to t3. Hence, the ratio between the difference of estimated fetal weights and the average of the two weights (difference average ratio) increases in proportion to (t-5)5/t3. In mild cases, the difference between estimated fetal weights as well as the sum of the two weights increases proportional to t3. Therefore, the difference average ratio becomes a constant. Comparison with clinical data of severe and mild cases showed surprisingly good agreement except after laser coagulation of placental anastomoses. These relations may therefore enable us to distinguish between severe and mild developing twin-twin transfusion syndrome cases.

  9. Comparing diagnostic tests: trials in people with discordant test results.

    PubMed

    Hooper, R; Díaz-Ordaz, K; Takeda, A; Khan, K

    2013-06-30

    Diagnostic tests are traditionally compared for accuracy against a gold standard but can also be compared prospectively in a trial. A conventional trial comparing two tests would randomize each participant to a testing strategy, but a more efficient alternative is to give both tests to all participants and follow up those with discordant results. Participants could be randomized before or after testing. The statistical analysis of such a trial has not previously been described. We investigated two estimates of the risk difference for a binary outcome: one based on analysing outcomes as if from a conventional trial and one combining estimates of different parameters in the manner of a decision analysis. We show that the trial estimate and decision analysis estimate are both unbiased and derive approximate formulae for their standard errors. By using the decision analysis estimate (but not the trial estimate), the same precision can be achieved by randomizing before testing as by randomizing after. To avoid destroying equipoise, and to allow consenting and randomizing to be carried out at the same visit, we recommend randomizing before testing. Giving both tests to all participants means fewer need to be recruited: in one example from the literature, the proposed design was nearly four times more efficient in this sense than a conventional trial design. PMID:23172716

  10. Discordant introgression in a rapidly expanding hybrid swarm

    PubMed Central

    Ward, Jessica L; Blum, Mike J; Walters, David M; Porter, Brady A; Burkhead, Noel; Freeman, Byron

    2012-01-01

    The erosion of species boundaries can involve rapid evolutionary change. Consequently, many aspects of the process remain poorly understood, including the formation, expansion, and evolution of hybrid swarms. Biological invasions involving hybridization present exceptional opportunities to study the erosion of species boundaries because timelines of interactions and outcomes are frequently well known. Here, we examined clinal variation across codominant and maternally inherited genetic markers as well as phenotypic traits to characterize the expansion and evolution of a hybrid swarm between native Cyprinella venusta and invasive Cyprinella lutrensis minnows. Discordant introgression of phenotype, microsatellite multilocus genotype, and mtDNA haplotype indicates that the observable expansion of the C. venusta × C. lutrensis hybrid swarm is a false invasion front. Both parental and hybrid individuals closely resembling C. lutrensis are numerically dominant in the expansion wake, indicating that the non-native parental phenotype may be selectively favored. These findings show that cryptic introgression can extend beyond the phenotypic boundaries of hybrid swarms and that hybrid swarms likely expand more rapidly than can be documented from phenotypic variation alone. Similarly, dominance of a single parental phenotype following an introduction event may lead to instances of species erosion being mistaken for species displacement without hybridization. PMID:25568058

  11. PLANNING AND OPERATING COLLEGE UNION BUILDINGS.

    ERIC Educational Resources Information Center

    BUTTS, PORTER

    THIS MONOGRAPH IS A DISCUSSION OF FOUR ASPECTS OF STUDENT UNIONS. PART ONE DISCUSSES THE NATURE AND PURPOSE OF A UNION AND THE UNION AS A CAMPUS CENTER. PART TWO DEALS WITH THE PLANNING OF UNION BUILDINGS AND GIVES PROCEDURES, PRINCIPLES AND CAUTIONS. UNION FACILITIES AND SERVICES ARE LISTED. PART THREE DISCUSSES THE ORGANIZATION AND ACTIVITIES OF…

  12. HIV testing, care, and treatment experiences among the steady male partners of female sex workers living with HIV in the Dominican Republic.

    PubMed

    Fleming, Paul J; Barrington, Clare; Perez, Martha; Donastorg, Yeycy; Kerrigan, Deanna

    2016-06-01

    Male steady partners of female sex workers (FSW) living with human immunodeficiency virus (HIV) represent a key population for treatment as prevention and/or pre-exposure prophylaxis interventions. This study uses data collected from male steady partners who were referred by FSW living with HIV participating in a multi-level HIV prevention and care intervention in Santo Domingo, Dominican Republic. We conducted a socio-behavioral survey and HIV testing with all men (n = 64) and 16 in-depth interviews with a sub-sample to obtain more depth. Thirty-five of the 64 participants were living with HIV; 27 were previously diagnosed and 8 were diagnosed during our study. As a result, 45% of men were members of sero-discordant sexual partnerships. Of men with no previous HIV diagnosis (n = 37), 15 had never been tested for HIV and nine had not been tested in the past two years. Ninety-three percent of men previously diagnosed with HIV reported receiving HIV care in the past 6 months and 78% were taking anti-retrovirals. Low HIV testing was partly due to men not feeling at risk for HIV, despite having an HIV-infected partner. Additionally, a lack of tailored care inhibited engagement in anti-retroviral treatment for those infected. HIV testing was low, highlighting a need for test-and-treat strategies. Men not living with HIV would benefit from regular testing and would be good candidates for pre-exposure prophylaxis. While almost all men who had been diagnosed with HIV were engaged in care and adherent to anti-retroviral therapy, future research should assess whether they are achieving optimal HIV outcomes for their health and prevention of ongoing transmission. PMID:27009379

  13. Professional Employees Turn to Unions

    ERIC Educational Resources Information Center

    Chamot, Dennis

    1976-01-01

    White-collar and professional employees are increasingly turning to unions to combat their loss of independence as employees of large organizations. Managers should realize that they and professional employees have different viewpoints about job situations and that the current trend toward white-collar unionism is apt to continue. (JG)

  14. A Trade Union Sponsored Scheme

    ERIC Educational Resources Information Center

    Eddy, Max; Corcoran, J. P.

    1969-01-01

    Professor Max Eddy, Head of Purdue University's Department of Industrial Education, with the assistance of J.P. Corcoran, Director of a trade union training department, describe the development of a programme of training for apprentice instructors run jointly by the union and the university. (Editor)

  15. Teaching Reform and Union Reform.

    ERIC Educational Resources Information Center

    Kerchner, Charles T.; Mitchell, Douglas E.

    1986-01-01

    Reviews present labor statutes and examines three alternatives to current practices; proposes that teaching, by its nature, is not well administered by industrial standards or well adjudicated through industrial unionism. Suggests "professional unionism" as a means of effecting educational reform. (DR)

  16. Recent Developments in Compulsory Unionism.

    ERIC Educational Resources Information Center

    Mitchnick, Morton G.

    1993-01-01

    Looks at legal cases concerning the uses to which mandatory union dues are put. Considers the variety of approaches adopted in Switzerland, Spain, Belgium, and Germany and reviews how compulsory unionism has been treated in the courts in the United Kingdom, Denmark, the United States, and Canada. (JOW)

  17. Union Roles in Workplace Literacy.

    ERIC Educational Resources Information Center

    Hensley, Stephen Michael

    1993-01-01

    Discusses roles for labor unions in resolving workforce deficiencies, suggesting that labor, management, and government must work together to develop cooperative training initiatives. Describes labor's historic role in basic and workplace literacy training, lists skills workers need in the "new" workplace, describes exemplary union-management…

  18. A Credit-Union Project.

    ERIC Educational Resources Information Center

    Schmidt, Mary Ellen

    1997-01-01

    Describes establishing and running a credit union in a sixth-grade classroom. By establishing a classroom credit union, students can develop independence in solving real problems and model situations that occur in the real world to solve similar problems. (ASK)

  19. Teacher Unionization in School Governance

    ERIC Educational Resources Information Center

    Jacoby, Dan

    2011-01-01

    The role of unions in school governance is reviewed to note that labor operates in a larger context of principal-agent relationships. As agents for teachers, unions articulate the concerns that must be addressed if teachers are to be successfully enlisted in the struggle to reduce achievement gaps among at-risk students. Transcending industrial…

  20. Thinking about the Soviet Union.

    ERIC Educational Resources Information Center

    Perkovich, George

    In the United States, educators have had difficulty teaching about the Soviet Union. Students are often ignorant of the historical circumstances that have affected the U.S./Soviet relationship, and they are often miseducated by stereotypes they encounter in popular culture. This curriculum explores the government and economy of the Soviet Union,…

  1. Unions: Bread, Butter & Basic Skills.

    ERIC Educational Resources Information Center

    BCEL Newsletter for the Business Community, 1987

    1987-01-01

    Unions are natural providers of basic skills instruction. They are in daily workplace contact with their membership, are trusted to work on members' behalf, and speak the language of the worker. Unions are trying to address the needs of illiterate workers through collective bargaining arrangements in which employers contribute a percentage of…

  2. College/Labor Union Cooperation

    ERIC Educational Resources Information Center

    Abbott, William

    1977-01-01

    A survey of 1,054 institutions by the AACJC Service Center for Community College-Labor Union Cooperation concluded that while substantial joint undertakings exist between unions and community colleges, in many cases labor and community colleges are waiting for the other party to make the first move. (JG)

  3. Toward a More Perfect Union

    ERIC Educational Resources Information Center

    Schachter, Ron

    2010-01-01

    This article explores school districts such as New Haven (Connecticut) Public Schools, whose local union is an American Federation of Teachers (AFT) affiliate and where a shared concern for students has trumped the often adversarial union-management relationship. The author discusses what makes the successful contract negotiations headed by David…

  4. Proposed EU-India free trade agreement could impede manufacture of generic HIV drugs.

    PubMed

    Chu, Sandra Ka Hon

    2011-04-01

    Medical experts are warning that an international trade agreement being brokered between the European Union (EU) and India could greatly restrict the access of people living with HIV in the developing world to life-saving antiretroviral medication. PMID:21688702

  5. Union Presence, Class, and Individual Earnings Inequality.

    ERIC Educational Resources Information Center

    Leicht, Kevin T.; And Others

    1993-01-01

    Data from the Survey of Class Structure and Class Consciousness showed that union membership positively affects earnings of all workers, but union density affects only the working class. Interindustry union threats affect the wages of only nonunionized workers. (SK)

  6. Compulsory Unionism and the Demise of Education.

    ERIC Educational Resources Information Center

    Staub, Susan E.

    1981-01-01

    Argues that forced unionism for teachers and forced union fees are undemocratic. Maintains that teacher unions will represent the interests of their members only when they must compete for membership. (Author/WD)

  7. Trade Unions and the Economics Curriculum.

    ERIC Educational Resources Information Center

    Veale, Sarah

    1987-01-01

    Contends that a realistic approach to teaching economics requires learning about trade unions. Presents a role play of a trade union meeting that helps students think about how trade unions tackle problems. (BSR)

  8. Is growth-discordance in twins a substantial risk factor in adverse neonatal outcomes?

    PubMed

    Frezza, Simonetta; Gallini, Francesca; Puopolo, Maria; De Carolis, Maria P; D'Andrea, Vito; Guidone, Paola I; Luciano, Rita; Zuppa, Antonio A; Romagnoli, Costantino

    2011-10-01

    To evaluate whether growth discordance is an independent risk factor in the neonatal outcome of the smaller twin, all medical records of twin pregnancies delivered between 26 and 41 weeks during a 5-year period (January 2004-December 2008) were reviewed. Among the 49 selected twins, weight discordance was 15-20% in 7 infants, 21-30% in 16 infants, 31-40% in 16 infants and > 40% in 10 infants. No significant differences between the four groups were found with regards to obstetric complications and neonatal disease. Occurrence of birthweight below the 10th percentile and rate of admission to the neonatal intensive care unit significantly increased as intra-pair birthweight difference increased (p = .03). The > 40% discordant group had a significantly lower gestational age (p = .03), lower birthweight (p = .007) and a significantly higher mortality rate (4/10 versus 3/39 p = .04) in comparison with the other discordant groups. Multiple logistic regression analysis showed that birthweight was the single independent and consistent factor associated with elevated risks of mortality. For every 250 g increase in birthweight, the risk for mortality decreased by about 84% [RR 0.16(CI 0.00-0.70)]. Gestational age was the most reliable predictor for major neonatal complications. For every 1-week increase in gestational age a significant decreased risk for all outcomes was found. Discordance alone should not be considered as a predictor for adverse neonatal outcome. Neonatal outcome in discordant twins appears to be related to gestational age and birthweight rather than to the degree of discordance. PMID:21962140

  9. Discordance in diagnosis of osteoporosis using spine and hip bone densitometry

    PubMed Central

    Moayyeri, Alireza; Soltani, Akbar; Tabari, Nasibeh Khaleghnejad; Sadatsafavi, Mohsen; Hossein-neghad, Arash; Larijani, Bagher

    2005-01-01

    Background Diagnostic discordance for osteoporosis is the observation that the T-score of an individual patient varies from one key measurement site to another, falling into two different diagnostic categories identified by the World Health Organization (WHO) classification system. This study was conducted to evaluate the presence and risk factors for this phenomenon in a large sample of Iranian population. Methods Demographic data, anthropometric measurements, and risk factors for osteoporosis were derived from a database on 4229 patients referred to a community-based outpatient osteoporosis testing center from 2000 to 2003. Dual-energy X-ray absorptiometry (DXA) was performed on L1–L4 lumbar spine and total hip for all cases. Minor discordance was defined as present when the difference between two sites was no more than one WHO diagnostic class. Major discordance was present when one site is osteoporotic and the other is normal. Subjects with incomplete data were excluded. Results In 4188 participants (3848 female, mean age 53.4 ± 11.8 years), major discordance, minor discordance, and concordance of T-scores were seen in 2.7%, 38.9% and 58.3%, respectively. In multivariate logistic regression analysis, older age, menopause, obesity, and belated menopause were recognized as risk factors and hormone replacement therapy as a protective factor against T-score discordance. Conclusion The high prevalence of T-score discordance may lead to problems in interpretation of the densitometry results for some patients. This phenomenon should be regarded as a real and prevalent finding and physicians should develop a particular strategy approaching to these patients. PMID:15762986

  10. Proton MRS in twin pairs discordant for schizophrenia.

    PubMed

    Lutkenhoff, E S; van Erp, T G; Thomas, M A; Therman, S; Manninen, M; Huttunen, M O; Kaprio, J; Lönnqvist, J; O'Neill, J; Cannon, T D

    2010-03-01

    Proton magnetic resonance spectroscopy ((1)H MRS) neurometabolite abnormalities have been detected widely in subjects with and at risk for schizophrenia. We hypothesized that such abnormalities would be present both in patients with schizophrenia and in their unaffected twin siblings. We acquired magnetic resonance spectra (TR/TE=3000/30 ms) at voxels in the mesial prefrontal gray matter, left prefrontal white matter and left hippocampus in 14 twin pairs discordant for schizophrenia (2 monozygotic, 12 dizygotic), 13 healthy twin pairs (4 monozygotic, 9 dizygotic) and 1 additional unaffected co-twin of a schizophrenia proband. In the mesial prefrontal gray matter voxel, N-acetylaspartate (NAA), creatine+phosphocreatine (Cr), glycerophosphocholine+phosphocholine (Cho) and myo-inositol (mI) did not differ significantly between patients with schizophrenia, their unaffected co-twins or healthy controls. However, glutamate (Glu) was significantly lower in patients with schizophrenia (31%, percent difference) and unaffected co-twins (21%) than in healthy controls (collapsed across twin pairs). In the left hippocampus voxel, levels of NAA (23%), Cr (22%) and Cho (36%) were higher in schizophrenia patients compared with controls. Hippocampal NAA (25%), Cr (22%) and Cho (37%) were also significantly higher in patients than in their unaffected co-twins. Region-to-region differences in metabolite levels were also notable within all three diagnosis groups. These findings suggest that (1)H MRS neurometabolite abnormalities are present not only in patients with schizophrenia, but also in their unaffected co-twins. Thus, reduced mesial prefrontal cortical Glu and elevated hippocampal NAA, Cr and Cho may represent trait markers of schizophrenia risk and, when exacerbated, state markers of schizophrenia itself. PMID:18645571