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1.
AIDS Behav ; 28(11): 3910-3918, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39172185

RESUMEN

People with HIV face challenges securing housing and employment. Patient navigation is an effective intervention that can improve the receipt of these services, which have been linked to better health outcomes. The purpose of this study was to assess implementation of patient navigation in diverse delivery settings. We also evaluated the relationship between these services and health outcomes among participants. Twelve sites in the United States (N = 1,082) implemented navigation using single or multiple navigator interventions to improve housing, employment, viral suppression, and retention in care. Sites included health departments, health centers, and AIDS service organizations (ASO). Client-level data were used to model relationships of interest. Across the 12 sites, regardless of model, housing (odds ratio (OR) = 1.18, p < .001), employment (OR = 1.09, p < .001) and retention in care (OR 1.11, p = .007) improved significantly over time; however, viral suppression did not (OR = 1.04, p = .120). Regardless of model of care, patient navigation improved housing, employment, and retention in care. This study demonstrated that while navigation supports people with HIV in securing housing and employment, models using a more intensive format worked best in specific settings. While most studies focus on unimodal strategies, this study builds on the evidence by examining how navigation models can be delivered to reduce barriers to care.


Asunto(s)
Empleo , Infecciones por VIH , Vivienda , Navegación de Pacientes , Humanos , Masculino , Femenino , Adulto , Estados Unidos , Persona de Mediana Edad , Accesibilidad a los Servicios de Salud , Retención en el Cuidado/estadística & datos numéricos , Carga Viral
2.
AIDS Care ; 36(8): 1162-1171, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38943675

RESUMEN

Women of color are disproportionately impacted by HIV. Although PrEP effectively prevents HIV infection, PrEP coverage and knowledge remain low in this population. To address barriers to PrEP, we implemented women-centered and culturally appropriate Information Sessions (IS) delivered by staff from the population they serve to increase knowledge, awareness, and use of PrEP through telemedicine (e.g., PlushCare). Our analysis focuses on Latina women (LW) participants, given the dearth of literature dedicated to the needs of LW. We partnered with a woman-led community-based organization (CBO) to implement the strategy with LW clients. Health educators conducted 26 IS with 94 LW (20 in Spanish and 6 in English). Participants who completed the IS were invited for interviews to assess the acceptability and appropriateness of the IS to increase knowledge and awareness of PrEP and PlushCare. Four themes emerged from the thematic analysis: (1) IS increased knowledge and awareness of PrEP and PlushCare; (2) perceived acceptability and appropriateness of IS; (3) insufficient reasons to warrant use of PrEP; and (4) positive attitudes about PlushCare. Our findings suggest that a women-centered and culturally appropriate IS implemented through a trusted, woman-led CBO is an acceptable and appropriate implementation strategy to inform LW about PrEP.


Asunto(s)
Infecciones por VIH , Conocimientos, Actitudes y Práctica en Salud , Hispánicos o Latinos , Aceptación de la Atención de Salud , Profilaxis Pre-Exposición , Telemedicina , Humanos , Femenino , Hispánicos o Latinos/psicología , Infecciones por VIH/prevención & control , Infecciones por VIH/etnología , Adulto , Aceptación de la Atención de Salud/etnología , Aceptación de la Atención de Salud/psicología , Persona de Mediana Edad , Fármacos Anti-VIH/uso terapéutico , Adulto Joven , Investigación Cualitativa
3.
Arch Sex Behav ; 53(9): 3673-3685, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38977534

RESUMEN

In the United States, immigrant Latino men who have sex with men (ILMSM) are, compared to white MSM, disproportionately burdened by HIV and lack access to highly effective HIV prevention strategies, such as pre-exposure prophylaxis (PrEP). Qualitative research centered on exploring barriers that ILMSM experience in accessing PrEP and other sexual services is extremely limited, despite a high prevalence of HIV in this population. In this study, a purposive sample of ILMSM (n = 25) was recruited to participate in a semi-structured in-depth interview to identify the distinct barriers and facilitators ILMSM experience in accessing sexual health services given their complex intersectional identities of being an immigrant, Latino, and a sexual minority man. Using a thematic analysis approach, nine themes were generated from the data representing barriers and facilitators. Barriers included: (1) cost and a lack of health insurance, (2) complexity of PrEP assistance programs; (3) challenges related to the immigrant experience; (4) impact of gay stigma; and (5) communication challenges. Facilitators included: (1) improving affordability and accessibility of PrEP services; (2) receiving services from LGBT- or Latine LGBT-centered clinics; (3) receiving services from medical providers who are gay and/or Latino; and (4) providing targeted community outreach, education, and promotion of PrEP to ILMSM. While many of the barriers illuminated in the study were structural (e.g., cost and lack of health insurance), and not easy to overcome, the findings highlight a range of facilitators that can support access to PrEP and other sexual health services for ILMSM. Considering these findings, we suggest strategies that may enhance access to needed sexual health services among ILMSM.


Asunto(s)
Emigrantes e Inmigrantes , Infecciones por VIH , Accesibilidad a los Servicios de Salud , Hispánicos o Latinos , Profilaxis Pre-Exposición , Adulto , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Los Angeles , Aceptación de la Atención de Salud/estadística & datos numéricos , Aceptación de la Atención de Salud/psicología , Profilaxis Pre-Exposición/estadística & datos numéricos , Investigación Cualitativa , Minorías Sexuales y de Género , Salud Sexual , Estigma Social
4.
Ecol Appl ; 33(3): e2789, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36482023

RESUMEN

Adult mortality is often the most sensitive vital rate affecting at-risk wildlife populations. Therefore, road ecology studies often focus on adult mortality despite the possibility for roads to be hazardous to juvenile individuals during natal dispersal. Failure to quantify concurrent variation in mortality risk and population sensitivity across demographic states can mislead the efforts to understand and mitigate the effects of population threats. To compare relative population impacts from road mortality among demographic classes, we weighted mortality observations by applying reproductive value analysis to quantify expected stage-specific contributions to population growth. We demonstrate this approach for snapping turtles (Chelydra serpentina) observed on roads at two focal sites in Ontario, Canada, where we collected data for both live and dead individuals observed on roads. We estimated reproductive values using stage-classified matrix models to compare relative population-level impacts of adult and juvenile mortality. Reproductive value analysis is a tractable approach to assessing demographically variable effects for applications covering large spatial scales, nondiscrete populations, or where abundance data are lacking. For one site with long-term life-history data, we compared demographic frequency on roads to expected general population frequencies predicted by the matrix model. Our application of reproductive value is sex specific but, as juvenile snapping turtles lack external secondary sex characters, we estimated the sex ratio of road-crossing juveniles after dissecting and sexing carcasses collected on roads at five sites across central Ontario, Canada. Juveniles were more abundant on roads than expected, suggesting a substantial dispersal contribution, and the road-killed juvenile sex ratio approached 1:1. A higher proportion of juveniles were also found dead compared with adults, and cumulative juvenile mortality had similar population-level importance as adult mortality. This suggests that the impact of roads needs to be considered across all life stages, even in wildlife species with slow life histories, such as snapping turtles, that are particularly sensitive to adult mortality.


Asunto(s)
Tortugas , Humanos , Animales , Masculino , Femenino , Reptiles , Ontario , Animales Salvajes
5.
Ethn Health ; 28(1): 96-113, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35166623

RESUMEN

OBJECTIVES: We examined Latinx immigrants' perceptions of US policy related to restrictions on immigrants' use of public resources and their thoughts about the influence of these on immigrants' healthcare utilization. DESIGN: A series of 16 focus group discussions with Latinx immigrant men and women (documented and undocumented) (N = 130) were conducted between May and July 2017 across four US cities. RESULTS: Four central themes emerged: participants attributed the limited resources available for affordable healthcare for many uninsured US immigrants (both documented and undocumented) to the US government's view of immigrants as burdens on public resources and its subsequent unwillingness to dedicate funds for their care; participants expressed concerns, some unfounded, about negative immigration ramifications arising from diagnosis with health conditions perceived to be serious and/or expensive to treat; participants noted that some immigrants avoided using health programs and services to which they were entitled because of immigration concerns; finally, participants described how access to information on immigration laws and healthcare resources, and conversely, misinformation about these, influenced healthcare utilization. CONCLUSIONS: Participants were acutely aware of the image of immigrants as public charges or potential burdens on government resources that underlies US immigration policy. In some cases, participants came to inaccurate and potentially harmful conclusions about the substance of laws and regulations based on their beliefs about the government's rejection of immigrants who may burden public resources. This underscores the importance of ensuring that immigrants have access to information on immigration-related laws and regulations and on healthcare resources available to them. Participants noted that access to information also fostered resilience to widespread misinformation. Importantly, however, participants' beliefs had some basis in US immigration policy discourse. Law and policy makers should reconsider legislation and political commentary that frame self-reliance, the guiding principle of US immigration policy, in terms of immigrants' use of publicly funded healthcare resources.


Asunto(s)
Emigrantes e Inmigrantes , Masculino , Femenino , Humanos , Atención a la Salud , Política Pública , Aceptación de la Atención de Salud , Hispánicos o Latinos , Accesibilidad a los Servicios de Salud
6.
Am Nat ; 200(4): 532-543, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36150201

RESUMEN

AbstractSpecies with environmental sex determination (ESD) have persisted through deep time, despite massive environmental perturbation in the geological record. Understanding how species with temperature-dependent sex determination (TSD), a type of ESD, persist through climate change is particularly timely given the current climate crisis, as highly biased sex ratios and extinction are predicted. Since 1982, we have studied primary sex ratios of a reptile with TSD (Chelydra serpentina). Primary sex ratios remained unchanged over time, despite warming in the environment. Resilience of the primary sex ratio occurred via a portfolio effect, realized through remarkable intra-annual variation in nest-level sex ratios, leading to a relatively consistent mean annual sex ratio. Intra-annual variation in nest-level sex ratios was related to variation in egg burial depth coupled with large clutch sizes, creating thermal gradients in the nest and promoting mixed-sex clutches. Furthermore, both locally and globally, sustained increases in nighttime air temperature contribute more to warming than increases in daily maximum temperature, but development rate was affected more strongly by maximum daily air temperature, conferring additional resilience to overall warming. Our study suggests that some TSD species may be resilient to warming and provides an example of how ESD may persist under environmental change.


Asunto(s)
Razón de Masculinidad , Tortugas , Animales , Cambio Climático , Reptiles , Procesos de Determinación del Sexo , Temperatura
7.
AIDS Behav ; 26(11): 3667-3678, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35687188

RESUMEN

Persons living with HIV (PLWH) with socio-economic vulnerabilities are especially vulnerable to HIV stigma and adverse HIV outcomes. Stigma related to HIV may intersect with marginalized socio-economic conditions to negatively affect social networks. HIV stigma may limit the ability of individuals to sustain social relationships. This study examined the potential cross-sectional and longitudinal associations between HIV stigma and the quality and quantity of social networks for PLWH. PLWH (n = 1,082) who were experiencing housing, employment, and medical care-related difficulties were recruited to participate in a one-year navigation and system coordination intervention to improve housing stability and employment. Neither stigma reduction nor social networks were the main components of the intervention. A series of latent growth curves were estimated to assess the cross-sectional and longitudinal relationships among internalized and anticipated HIV stigma and social networks. Anticipated HIV stigma predicted social networks both cross-sectionally and longitudinally. Internalized HIV stigma predicted social networks cross-sectionally but not longitudinally in this population. These data support the HIV Stigma Framework and suggest that anticipated stigma seems to have a strong association with social networks. As anticipated stigma decreases over time, social network scores increase. Interventions to decrease anticipated HIV stigma as a mechanism of improving social networks warrants further investigation.


Asunto(s)
Infecciones por VIH , Estudios Transversales , Infecciones por VIH/epidemiología , Humanos , Red Social , Estigma Social , Encuestas y Cuestionarios
8.
AIDS Care ; 33(2): 244-252, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32449399

RESUMEN

The purpose of this qualitative study was to identify barriers and motivators to PrEP uptake from the perspective of Black and Latina transgender women (TW) who are currently using PrEP to suggest intervention and outreach activities to increase PrEP uptake in this population. The Information-Motivation-Behavioral Skills Model guided the development of the semi-structured interview guide. A thematic analysis approach was used to analyze the data. Perceived barriers to PrEP uptake included structural and logistic barriers, language and cultural barriers to medical engagement, lack of transgender competent or gender-affirming care, and prioritizing hormone therapy over the use of PrEP. To increase PrEP uptake among BLTW, participants recommended disseminating PrEP information through a variety of methods, highlighting relationship and sexual health benefits of using PrEP, and developing effective patient-provider communication. Our findings highlight several ways to promote PrEP among BLTW. PrEP promotion should be integrated into gender-affirming care and supported by peer education and navigation services that reach BLTW in both clinic and community settings.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Negro o Afroamericano/psicología , Infecciones por VIH/prevención & control , Hispánicos o Latinos/psicología , Profilaxis Pre-Exposición , Personas Transgénero/psicología , Negro o Afroamericano/estadística & datos numéricos , Anciano , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/etnología , Accesibilidad a los Servicios de Salud , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Los Angeles , Masculino , Medicare , Persona de Mediana Edad , Estigma Social , Personas Transgénero/estadística & datos numéricos , Estados Unidos
9.
J Urban Health ; 97(5): 679-691, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31214977

RESUMEN

Black men who have sex with men (BMSM) are disproportionately affected by HIV infection in the USA. Pre-exposure prophylaxis (PrEP) is a proven efficacious biomedical prevention strategy with the potential to alter significantly the course of the epidemic in this population. However, the social stigma attached to PrEP and those who use it may act as a barrier to the uptake and continuation of PrEP among high-risk BMSM. In-depth, semi-structured qualitative interviews were conducted with 26 BMSM PrEP users to explore their experiences of stigma related to their PrEP use. BMSM reported multiple experiences or manifestations of PrEP-related stigma, which included (1) perception that PrEP users engage in elevated sexual risk behaviors; (2) conflicts in relationships attributed to PrEP; (3) experiences of discomfort or judgment from medical providers; (4) assumption that PrEP users are HIV-positive; and (5) gay stigma in families limiting PrEP disclosure. The experiences of stigma typically occur within the context of PrEP disclosure and have significant personal and social consequences for PrEP users. Efforts to address PrEP and other social-stigmas within the Black community may help facilitate PrEP uptake and continuation with BMSM.


Asunto(s)
Negro o Afroamericano/psicología , Infecciones por VIH/prevención & control , Homosexualidad Masculina/psicología , Profilaxis Pre-Exposición/estadística & datos numéricos , Sexo Seguro/psicología , Conducta Sexual/psicología , Estigma Social , Adulto , Negro o Afroamericano/estadística & datos numéricos , Infecciones por VIH/epidemiología , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Los Angeles/epidemiología , Masculino , Prevalencia , Asunción de Riesgos , Estados Unidos/epidemiología , Adulto Joven
10.
Oecologia ; 193(4): 903-912, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32809054

RESUMEN

Dispersal is a fundamental ecological process that can be affected by population density, yet studies report contrasting effects of density on propensity to disperse. In addition, the relationship between dispersal and density is seldom examined using densities measured at different spatial scales or over extensive time series. We used 51 years of trapping data to examine how dispersal by wild deer mice (Peromyscus maniculatus) was affected by changes in both local and regional population densities. We examined these patterns over both the entire time series and also in 10-year shifting windows to determine whether the nature and strength of the relationship changed through time. Probability of dispersal decreased with increased local and regional population density, and the negative effect of local density on dispersal was more pronounced in years with low regional densities. In addition, the strength of negative density-dependent dispersal changed through time, ranging from very strong in some decades to absent in other periods of the study. Finally, while females were less likely to disperse, female dispersal was more density-dependent than male dispersal. Our study shows that the relationship between density and dispersal is not temporally static and that investigations of density-dependent dispersal should consider both local and regional population densities.


Asunto(s)
Bosques , Roedores , Animales , Femenino , Masculino , Ratones , Densidad de Población , Dinámica Poblacional
11.
Cult Health Sex ; : 1-14, 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-32996431

RESUMEN

Health care providers have an important role to play in expanding PrEP uptake to populations disproportionately burdened by HIV. In this study, in-depth, semi-structured qualitative interviews were conducted with 20 PrEP providers in Los Angeles, California to explore their experiences and perspectives prescribing PrEP. Overall, the findings indicate that providers generally adhered to US CDC clinical guidelines in determining PrEP eligibility. However, they also identified special considerations with respect to adults with "low" or "no" HIV risk. Three themes were developed from the data related to the delivery of PrEP to such individuals: 1) patients may not disclose sexual behaviours; 2) patient autonomy and agency; and 3) the importance of PrEP in gay male monogamous relationships. Two additional themes were identified related to prescribing PrEP to young people under the age of consent: 4) the need for more PrEP and sexual health education with youth and 5) challenges in providing PrEP to youth without parental consent. Findings highlight the importance of providing PrEP to patients who could potentially benefit from adoption, whether or not they present with clear behavioural indicators for PrEP. Providers should also consider the potential barriers to delivering PrEP to youth to ensure successful adoption among members of this population.

12.
J Med Internet Res ; 22(11): e18309, 2020 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-33136057

RESUMEN

BACKGROUND: Consistent with young adults' penchant for digital communication, young adults living with HIV use digital communication media to seek out health information. Understanding the types of health information sought online and the characteristics of these information-seeking young adults is vital when designing digital health interventions for them. OBJECTIVE: This study aims to describe characteristics of young adults living with HIV who seek health information through the internet. Results will be relevant to digital health interventions and patient education. METHODS: Young adults with HIV (aged 18-34 years) self-reported internet use during an evaluation of digital HIV care interventions across 10 demonstration projects in the United States (N=716). Lasso (least absolute shrinkage and selection operator) models were used to select characteristics that predicted whether participants reported seeking general health and sexual and reproductive health (SRH) information on the internet during the past 6 months. RESULTS: Almost a third (211/716, 29.5%) and a fifth (155/716, 21.6%) of participants reported searching for general health and SRH information, respectively; 26.7% (36/135) of transgender young adults with HIV searched for gender-affirming care topics. Areas under the curve (>0.70) indicated success in building models to predict internet health information seeking. Consistent with prior studies, higher education and income predicted health information seeking. Higher self-reported antiretroviral therapy adherence, substance use, and not reporting transgender gender identity also predicted health information seeking. Reporting a sexual orientation other than gay, lesbian, bisexual, or straight predicted SRH information seeking. CONCLUSIONS: Young adults living with HIV commonly seek both general health and SRH information online, particularly those exploring their sexual identity. Providers should discuss the most commonly sought SRH topics and the use of digital technology and be open to discussing information found online to better assist young adults with HIV in finding accurate information. Characteristics associated with health information-seeking behavior may also be used to develop and tailor digital health interventions for these young adults.


Asunto(s)
Infecciones por VIH/epidemiología , Conducta en la Búsqueda de Información/ética , Adolescente , Adulto , Femenino , Conductas Relacionadas con la Salud , Humanos , Estudios Longitudinales , Masculino , Estados Unidos , Adulto Joven
13.
Health Promot Pract ; 21(5): 693-704, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32757839

RESUMEN

Youth and young adults living with HIV (YYALH) are less likely to be engaged in HIV care, adhere to their medications, and achieve viral suppression compared to older adult populations. In the United States, the majority of YYALH belong to racial/ethnic, sexual, and gender minority groups. HIV care interventions are needed that specifically target YYALH and that exploit the use of social media and mobile technology (SMMT) platforms, where youth and young adults have a ubiquitous presence. We conducted a qualitative evaluation of SMMT interventions included in a Health Resources and Services Administration Special Projects of National Significance initiative designed to improve medical care engagement, retention, and medication adherence to achieve viral suppression among YYALH. However, in this study, only young adults living with HIV (YALH) ages 18 to 34 years participated. A total of 48 YALH were interviewed. The data were analyzed using thematic analysis and revealed three main themes supporting the usefulness of the SMMT interventions, which included (1) acceptability of SMMT interventions in managing HIV care with subthemes of medical information accessibility, reminders, and self-efficacy; (2) feelings of support and personal connection afforded by SMMT interventions; and (3) SMMT interventions help to alleviate negative feelings about status and mitigate HIV-related stigma. A few participants identified problems with using their respective intervention, primarily related to the functionality of the technologies. Overall, findings from our qualitative evaluation suggest that SMMT-based interventions have the potential to increase engagement and retention in care, support YALH in adhering to medication, and help them adjust to their diagnosis.


Asunto(s)
Infecciones por VIH , Medios de Comunicación Sociales , Adolescente , Adulto , Anciano , Infecciones por VIH/tratamiento farmacológico , Humanos , Evaluación de Resultado en la Atención de Salud , Tecnología , Estados Unidos , United States Health Resources and Services Administration , Adulto Joven
14.
Health Promot Pract ; 21(5): 705-715, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32757834

RESUMEN

Social media platforms offer the opportunity to develop online social networks. Use of these platforms has been particularly attractive to younger sexual and gender minority individuals as well as those living with HIV. This cross-sectional study examined the perceived level of social support and associations with social media use among youth and young adult cisgender men who have sex with men (MSM) and transgender (trans) women living with HIV and examined these associations by gender identity. The study drew from baseline data collected from 612 cisgender MSM and 162 trans women enrolling in one of 10 demonstration sites that were part of a Health Resources and Services Administration Special Projects of National Significance initiative. The individual projects were designed to evaluate the potential for social media/mobile technology-based interventions to improve retention in care and HIV health outcomes. The data used in this study came from baseline surveys completed when participants enrolled in a site between October 2016 and May 2018. Results demonstrated that a significantly greater proportion of MSM than trans women participants reported the use of social media platforms (e.g., Facebook: MSM = 86%, trans women = 62%; Instagram: MSM = 65%, trans women = 35%). Furthermore, increased social media use improved perceptions of social support only among MSM participants (direct adjusted OR = 1.49) and not trans women participants (gender identity interaction term adjusted OR = 0.64). These results revealed that MSM participants perceived greater social benefit from the use of social media platforms than trans women, which could be a result of generalized online transphobia experienced by trans women. More nuanced data on various social media platforms, that is, anonymous versus profile-based, and group differences, are needed to better understand how social media platforms can be best utilized to optimize health care outcomes among sexual and gender minority youth and young adults living with HIV.


Asunto(s)
Infecciones por VIH , Minorías Sexuales y de Género , Medios de Comunicación Sociales , Personas Transgénero , Adolescente , Estudios Transversales , Femenino , Identidad de Género , Homosexualidad Masculina , Humanos , Masculino , Estigma Social , Apoyo Social , Adulto Joven
15.
J Exp Biol ; 222(Pt 1)2019 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-30352829

RESUMEN

For many oviparous animals, incubation temperature influences sex through temperature-dependent sex determination (TSD). Although climate change may skew sex ratios in species with TSD, few available methods predict sex under natural conditions, fewer still are based on mechanistic hypotheses of development, and field tests of existing methods are rare. We propose a new approach that calculates the probability of masculinization (PM) in natural nests. This approach subsumes the mechanistic hypotheses describing the outcome of TSD, by integrating embryonic development with the temperature-dependent reaction norm for sex determination. Further, we modify a commonly used method of sex ratio estimation, the constant temperature equivalent (CTE), to provide quantitative estimates of sex ratios. We test our new approaches using snapping turtles (Chelydra serpentina). We experimentally manipulated nests in the field, and found that the PM method is better supported than the modified CTE, explaining 69% of the variation in sex ratios across 27 semi-natural nests. Next, we used the PM method to predict variation in sex ratios across 14 natural nests over 2 years, explaining 67% of the variation. We suggest that the PM approach is effective and broadly applicable to species with TSD, particularly for forecasting how sex ratios may respond to climate change. Interestingly, we also found that the modified CTE explained up to 64% of variation in sex ratios in a Type II TSD species, suggesting that our modifications will be useful for future research. Finally, our data suggest that the Algonquin Park population of snapping turtles possesses resilience to biased sex ratios under climate change.


Asunto(s)
Cambio Climático , Calor , Procesos de Determinación del Sexo/fisiología , Razón de Masculinidad , Tortugas/fisiología , Animales , Desarrollo Embrionario
16.
AIDS Behav ; 23(7): 1964-1973, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30649635

RESUMEN

Latino men who have sex with men (MSM) are a group critically affected by HIV. Pre-exposure Prophylaxis (PrEP) is a biomedical prevention strategy that can help reduce new infections in this population. However, PrEP use may expose users to experiences of PrEP-related stigma. In-depth interviews conducted with Latino MSM PrEP users (N = 29) were analyzed using thematic analysis to explore experiences of PrEP stigma. Six themes emerged related to anticipated and enacted PrEP stigma: (1) Perception that PrEP users engage in risky sexual behaviors; (2) PrEP-induced conflict in relationships; (3) Perception that PrEP users are HIV-positive; (4) Generational differences in attitudes toward HIV prevention; (5) Experiences of discomfort, judgment, or homophobia from medical providers; and (6) Gay stigma related to PrEP disclosure to family. Manifestations of stigma included disapproving judgment, negative labeling, rejection, and devaluing individuals. The social consequences associated with using PrEP may deter uptake and persistence among Latino MSM.


Asunto(s)
Infecciones por VIH/prevención & control , Homosexualidad Masculina/psicología , Profilaxis Pre-Exposición , Estigma Social , Adulto , Fármacos Anti-VIH/uso terapéutico , Combinación Emtricitabina y Fumarato de Tenofovir Disoproxil/uso terapéutico , Hispánicos o Latinos , Humanos , Los Angeles , Masculino , Persona de Mediana Edad , Asunción de Riesgos , Sexo Seguro , Conducta Sexual , Parejas Sexuales , Adulto Joven
17.
AIDS Care ; 31(4): 427-435, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30021456

RESUMEN

The Centers for Disease Control and Prevention (CDC) estimates the lifetime HIV risk is one in four for Latino men who have sex with men (MSM). Pre-Exposure Prophylaxis (PrEP) is an efficacious biomedical prevention strategy to help prevent the acquisition of HIV. At present, there has been limited uptake of PrEP by Latino MSM. Unfortunately, the negative perceptions and social stigma surrounding PrEP and those who use it may deter uptake of this novel prevention strategy, particularly among high-risk Latino MSM. In this qualitative study, we explore the experiences of using PrEP among Latino MSM. Participants were recruited using gay-oriented social and sexual networking apps to complete an interviewer-administered, semi-structured qualitative interview. Thematic analysis was used to identify emerging themes relating to perceptions of PrEP users and PrEP as an HIV prevention strategy. Major themes included: feelings of protection and sexual freedom; negative and stigmatizing labels associated with PrEP use; assumptions about sexual behaviors and perceptions of sexual risk taking and irresponsibility; and attitudes related to PrEP use in relationships. A striking but not prevalent theme was the perception reported by participants that monolingual Spanish-speaking Latino MSM are skeptical about the effectiveness of PrEP. These findings suggest that efforts are needed to address the stigmatizing and negative perceptions of PrEP that persist in the gay community that may deter adoption among Latino MSM.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Infecciones por VIH/prevención & control , Hispánicos o Latinos/psicología , Homosexualidad Masculina/psicología , Profilaxis Pre-Exposición , Conducta de Reducción del Riesgo , Estigma Social , Adulto , Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Sexo Seguro , Conducta Sexual
18.
J Therm Biol ; 74: 187-194, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29801626

RESUMEN

Temperature has a strong effect on ectotherm development rate. It is therefore possible to construct predictive models of development that rely solely on temperature, which have applications in a range of biological fields. Here, we leverage a reference series of development stages for embryos of the turtle Chelydra serpentina, which was described at a constant temperature of 20 °C. The reference series acts to map each distinct developmental stage onto embryonic age (in days) at 20 °C. By extension, an embryo taken from any given incubation environment, once staged, can be assigned an equivalent age at 20 °C. We call this concept "Equivalent Development", as it maps the development stage of an embryo incubated at a given temperature to its equivalent age at a reference temperature. In the laboratory, we used the concept of Equivalent Development to estimate development rate of embryos of C. serpentina across a series of constant temperatures. Using these estimates of development rate, we created a thermal performance curve measured in units of Equivalent Development (TPCED). We then used the TPCED to predict developmental stage of embryos in several natural turtle nests across six years. We found that 85% of the variation of development stage in natural nests could be explained. Further, we compared the predictive accuracy of the model based on the TPCED to the predictive accuracy of a degree-day model, where development is assumed to be linearly related to temperature and the amount of accumulated heat is summed over time. Information theory suggested that the model based on the TPCED better describes variation in developmental stage in wild nests than the degree-day model. We suggest the concept of Equivalent Development has several strengths and can be broadly applied. In particular, studies on temperature-dependent sex determination may be facilitated by the concept of Equivalent Development, as development age maps directly onto the developmental series of the organism, allowing critical periods of sex determination to be delineated without invasive sampling, even under fluctuating temperature.


Asunto(s)
Modelos Biológicos , Temperatura , Tortugas/embriología , Animales , Embrión no Mamífero , Desarrollo Embrionario
19.
Ecology ; 98(2): 512-524, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27870008

RESUMEN

Life histories evolve in response to constraints on the time available for growth and development. Nesting date and its plasticity in response to spring temperature may therefore be important components of fitness in oviparous ectotherms near their northern range limit, as reproducing early provides more time for embryos to complete development before winter. We used data collected over several decades to compare air temperature and nest date plasticity in populations of painted turtles and snapping turtles from a relatively warm environment (southeastern Michigan) near the southern extent of the last glacial maximum to a relatively cool environment (central Ontario) near the northern extent of post-glacial recolonization. For painted turtles, population-level differences in reaction norm elevation for two phenological traits were consistent with adaptation to time constraints, but no differences in reaction norm slopes were observed. For snapping turtle populations, the difference in reaction norm elevation for a single phenological trait was in the opposite direction of what was expected under adaptation to time constraints, and no difference in reaction norm slope was observed. Finally, among-individual variation in individual plasticity for nesting date was detected only in the northern population of snapping turtles, suggesting that reaction norms are less canalized in this northern population. Overall, we observed evidence of phenological adaptation, and possibly maladaptation, to time constraints in long-lived reptiles. Where present, (mal)adaptation occurred by virtue of differences in reaction norm elevation, not reaction norm slope. Glacial history, generation time, and genetic constraint may all play an important role in the evolution of phenological timing and its plasticity in long-lived reptiles.


Asunto(s)
Fenotipo , Estaciones del Año , Tortugas/fisiología , Animales , Michigan , Ontario
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