Impact of equivalence class training on same/different learning by pigeons.

Separating and isolating the contributions of perception to concept formation in animals has been a long-standing and persistent challenge. Here we describe a novel approach to assessing this question by using equivalence training consisting of unrelated images as the basis for subsequent same/different (S/D) learning. Following equivalence class training, two groups of pigeons attempted to learn a go/no-go discrimination task constructed from these classes. In the go/no-go task, a consistent group was given an S/D assignment that aligned with this prior training (same vs. different classes). An inconsistent group was given go/no-go assignments that were misaligned with their established classes. The consistent group exhibited better learning and stimulus control in their S/D task than did the inconsistent group. These results suggest that pigeons can use trained properties derived from class-based information to learn an S/D task without the aid of perceptual similarity. This novel approach holds promise for helping to evaluate the contribution of perceptual similarity to different types of concept learning. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Role of Electronegativity in Environmentally Persistent Free Radicals (EPFRs) Formation on ZnO.

Environmentally persistent free radicals (EPFRs), a group of emerging pollutants, have significantly longer lifetimes than typical free radicals. EPFRs form by the adsorption of organic precursors on a transition metal oxide (TMO) surface involving electron charge transfer between the organic and TMO. In this paper, dihalogenated benzenes were incorporated to study the role of electronegativity in the electron transfer process to obtain a fundamental knowledge of EPFR formation mechanism on ZnO. Upon chemisorption on ZnO nanoparticles at 250 °C, electron paramagnetic resonance (EPR) confirms the formation of oxygen adjacent carbon-centered organic free radicals with concentrations between 1016 and 1017 spins/g. The radical concentrations show a trend of 1,2-dibromobenzene (DBB) > 1,2-dichlorobenzene (DCB) > 1,2-difluorobenzene (DFB) illustrating the role of electronegativity on the amount of radical formation. X-ray absorption spectroscopy (XAS) confirms the reduction of the Zn2+ metal center, contrasting previous experimental evidence of an oxidative mechanism for ZnO single crystal EPFR formation. The extent of Zn reduction for the different organics (DBB > DCB > DFB) also correlates to their polarity. DFT calculations provide theoretical evidence of ZnO surface reduction and exhibit a similar trend of degree of reduction for different organics, further building on the experimental findings. The lifetimes of the EPFRs formed confirm a noteworthy persistency.

Perspectives Among Health Care Providers and People with HIV on the Implementation of Long-Acting Injectable Cabotegravir/Rilpivirine for Antiretroviral Therapy in Florida.

Long-acting injectable (LAI) cabotegravir/rilpivirine (CAB/RPV) for antiretroviral therapy (ART) could benefit many people with HIV (PWH). However, its impact will largely be determined by providers' willingness to prescribe it and PWH's willingness to take it. This study explores the perceived barriers and facilitators of LAI CAB/RPV implementation among PWH and HIV care providers in Florida, a high prevalence setting. Semi-structured qualitative interviews were conducted in English with 16 PWH (50% non-Hispanic White, 50% cis men, and 94% on oral ART) and 11 providers (27% non-Hispanic Black, 27% Hispanic, 73% cis women, and 64% prescribed LAI CAB/RPV) throughout the state. Recruitment occurred between October 2022 and October 2023 from HIV clinics. Interviews were recorded, professionally transcribed, and then double coded using thematic analysis. The Consolidated Framework for Implementation Research guided the interview guide and coding. While PWH viewed LAI CAB/RPV as effective, predominant barriers included administration via injection, challenges of attending more clinic visits, and a feeling that this made HIV the center of one's life. Providers additionally expressed concerns about the development of integrase resistance. Barriers noted by PWH and providers outside of the clinic included transportation, stigma, access inequities, and payor issues. Within clinics, providers identified the need for extra staffing and the increased burden on existing staff as barriers. These barriers decreased the perceived need for LAI CAB/RPV among PWH and providers, especially with the high effectiveness of oral ART. Many of the identified barriers occur outside of the clinic and will likely apply to other novel long-acting ART options.

Experimentally Induced Reductions in Alcohol Consumption and Brain, Cognitive, and Clinical Outcomes in Older Persons With and Those Without HIV Infection (30-Day Challenge Study): Protocol for a Nonrandomized Clinical Trial.

BACKGROUND: Both alcohol consumption and HIV infection are associated with worse brain, cognitive, and clinical outcomes in older adults. However, the extent to which brain and cognitive dysfunction is reversible with reduction or cessation of drinking is unknown. OBJECTIVE: The 30-Day Challenge study was designed to determine whether reduction or cessation of drinking would be associated with improvements in cognition, reduction of systemic and brain inflammation, and improvement in HIV-related outcomes in adults with heavy drinking. METHODS: The study design was a mechanistic experimental trial, in which all participants received an alcohol reduction intervention followed by repeated assessments of behavioral and clinical outcomes. Persons were eligible if they were 45 years of age or older, had weekly alcohol consumption of 21 or more drinks (men) or 14 or more drinks (women), and were not at high risk of alcohol withdrawal. After a baseline assessment, participants received an intervention consisting of contingency management (money for nondrinking days) for at least 30 days followed by a brief motivational interview. After this, participants could either resume drinking or not. Study questionnaires, neurocognitive assessments, neuroimaging, and blood, urine, and stool samples were collected at baseline, 30 days, 90 days, and 1 year after enrollment. RESULTS: We enrolled 57 persons with heavy drinking who initiated the contingency management protocol (mean age 56 years, SD 4.6 years; 63%, n=36 male, 77%, n=44 Black, and 58%, n=33 people with HIV) of whom 50 completed 30-day follow-up and 43 the 90-day follow-up. The planned study procedures were interrupted and modified due to the COVID-19 pandemic of 2020-2021. CONCLUSIONS: This was the first study seeking to assess changes in brain (neuroimaging) and cognition after alcohol intervention in nontreatment-seeking people with HIV together with people without HIV as controls. Study design strengths, limitations, and lessons for future study design considerations are discussed. Planned analyses are in progress, after which deidentified study data will be available for sharing. TRIAL REGISTRATION: ClinicalTrials.gov NCT03353701; https://clinicaltrials.gov/study/NCT03353701. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/53684.

Spatial and temporal analysis of HIV clinical outcomes in Florida reveals counties with persistent racial and ethnic disparities during 2012-2019.

BACKGROUND: Racial/ethnic disparities in the HIV care continuum have been well documented in the US, with especially striking inequalities in viral suppression rates between White and Black persons with HIV (PWH). The South is considered an epicenter of the HIV epidemic in the US, with the largest population of PWH living in Florida. It is unclear whether any disparities in viral suppression or immune reconstitution-a clinical outcome highly correlated with overall prognosis-have changed over time or are homogenous geographically. In this analysis, we 1) investigate longitudinal trends in viral suppression and immune reconstitution among PWH in Florida, 2) examine the impact of socio-ecological factors on the association between race/ethnicity and clinical outcomes, 3) explore spatial and temporal variations in disparities in clinical outcomes. METHODS: Data were obtained from the Florida Department of Health for 42,369 PWH enrolled in the Ryan White program during 2008-2020. We linked the data to county-level socio-ecological variables available from County Health Rankings. GEE models were fit to assess the effect of race/ethnicity on immune reconstitution and viral suppression longitudinally. Poisson Bayesian hierarchical models were fit to analyze geographic variations in racial/ethnic disparities while adjusting for socio-ecological factors. RESULTS: Proportions of PWH who experienced viral suppression and immune reconstitution rose by 60% and 45%, respectively, from 2008-2020. Odds of immune reconstitution and viral suppression were significantly higher among White [odds ratio =2.34, 95% credible interval=2.14-2.56; 1.95 (1.85-2.05)], and Hispanic [1.70 (1.54-1.87); 2.18(2.07-2.31)] PWH, compared with Black PWH. These findings remained unchanged after accounting for socio-ecological factors. Rural and urban counties in north-central Florida saw the largest racial/ethnic disparities. CONCLUSIONS: There is persistent, spatially heterogeneous, racial/ethnic disparity in HIV clinical outcomes in Florida. This disparity could not be explained by socio-ecological factors, suggesting that further research on modifiable factors that can improve HIV outcomes among Black and Hispanic PWH in Florida is needed.

A Behavioral Economic Examination of Sexual Behaviors in the Era of Pre-exposure Prophylaxis via Explanatory Sequential Mixed Methods.

Pre-exposure prophylaxis (PrEP) use may be associated with condom use decisions. The current investigation examined sexual decision-making in the context of PrEP among young adult men who have sex with men (MSM) between 18 and 30 years old, using an explanatory sequential mixed methods design. For the quantitative aim, 99 MSM currently taking PrEP (i.e., PrEP-experienced) and 140 MSM not currently taking PrEP (i.e., PrEP-naive) completed an online survey, including the Sexual Delay Discounting Task (SDDT), which captures likelihood of condom use. For the qualitative aim, 15 people from each group were interviewed about their (1) conceptualizations of risky sex and (2) ways they manage their sexual risk. Participants were, on average, 25.69 years old (SD = 3.07) and 64% White. Results from the quantitative aim revealed, controlling for covariates, PrEP-experienced participants exhibited significantly lower likelihood of (1) using an immediately available condom and (2) waiting for a delayed condom (i.e., sexual delay discounting) compared to PrEP-naive participants. Qualitative themes explaining what young adult MSM consider to be risky sex included: (1) any sex as risky sex, (2) risky sex as "sex without a conversation," and (3) risky sex as sex with risk for physical harm. Themes on ways young adult MSM manage sexual risk were classified as proactive, reactive, and passive. Results suggest that PrEP use is related to condom use decisions. Taken together, quantitative differences in sexual delay discounting, but qualitatively similar conceptualizations and management of risky sex, suggest that the SDDT may be a useful tool in sex research to capture processes (i.e., delay discounting) underlying sexual decision-making that may be missed by traditional self-reports. Implications of results, including potentially providing (good quality) condoms with every PrEP prescription, and future research topics are discussed.

Comorbidity Burden and Health Care Utilization by Substance use Disorder Patterns among People with HIV in Florida.

Substance use disorder (SUD), a common comorbidity among people with HIV (PWH), adversely affects HIV clinical outcomes and HIV-related comorbidities. However, less is known about the incidence of different chronic conditions, changes in overall comorbidity burden, and health care utilization by SUD status and patterns among PWH in Florida, an area disproportionately affected by the HIV epidemic. We used electronic health records (EHR) from a large southeastern US consortium, the OneFlorida + clinical research data network. We identified a cohort of PWH with 3 + years of EHRs after the first visit with HIV diagnosis. International Classification of Diseases (ICD) codes were used to identify SUD and comorbidity conditions listed in the Charlson comorbidity index (CCI). A total of 42,271 PWH were included (mean age 44.5, 52% Black, 45% female). The prevalence SUD among PWH was 45.1%. Having a SUD diagnosis among PWH was associated with a higher incidence for most of the conditions listed on the CCI and faster increase in CCI score overtime (rate ratio = 1.45, 95%CI 1.42, 1.49). SUD in PWH was associated with a higher mean number of any care visits (21.7 vs. 14.8) and more frequent emergency department (ED, 3.5 vs. 2.0) and inpatient (8.5 vs. 24.5) visits compared to those without SUD. SUD among PWH was associated with a higher comorbidity burden and more frequent ED and inpatient visits than PWH without a diagnosis of SUD. The high SUD prevalence and comorbidity burden call for improved SUD screening, treatment, and integrated care among PWH.

Intersectional Stigma, Fear of Negative Evaluation, Depression, and ART Adherence Among Women Living with HIV Who Engage in Substance Use: A Latent Class Serial Mediation Analysis.

Women Living with HIV (WLHIV) who use substances face stigma related to HIV and substance use (SU). The relationship between the intersection of these stigmas and adherence to antiretroviral therapy (ART), as well as the underlying mechanisms, remains poorly understood. This study aimed to examine the association between intersectional HIV and SU stigma and ART adherence, while also exploring the potential role of depression and fear of negative evaluation (FNE) by other people in explaining this association. We analyzed data from 409 WLHIV collected between April 2016 and April 2017, Using Multidimensional Latent Class Item Response Theory analysis. We identified five subgroups (i.e., latent classes [C]) of WLHIV with different combinations of experienced SU and HIV stigma levels: (C1) low HIV and SU stigma; (C2) moderate SU stigma; (C3) higher HIV and lower SU stigma; (C4) moderate HIV and high SU stigma; and (C5) high HIV and moderate SU stigma. Medication adherence differed significantly among these classes. Women in the class with moderate HIV and high SU stigma had lower adherence than other classes. A serial mediation analysis suggested that FNE and depression symptoms are mechanisms that contribute to explaining the differences in ART adherence among WLHIV who experience different combinations of intersectional HIV and SU stigma. We suggest that FNE is a key intervention target to attenuate the effect of intersectional stigma on depression symptoms and ART adherence, and ultimately improve health outcomes among WLHIV.

New Features of Laboratory-Generated EPFRs from 1,2-Dichlorobenzene (DCB) and 2-Monochlorophenol (MCP).

The present research is primarily focused on investigating the characteristics of environmentally persistent free radicals (EPFRs) generated from commonly recognized aromatic precursors, namely, 1,2-dichlorobenzene (DCB) and 2-monochlorophenol (MCP), within controlled laboratory conditions at a temperature of 230 °C, termed as DCB230 and MCP230 EPFRs, respectively. An intriguing observation has emerged during the creation of EPFRs from MCP and DCB utilizing a catalyst 5% CuO/SiO2, which was prepared through various methods. A previously proposed mechanism, advanced by Dellinger and colleagues (a conventional model), postulated a positive correlation between the degree of hydroxylation on the catalyst's surface (higher hydroxylated, HH and less hydroxylated, LH) and the anticipated EPFR yields. In the present study, this correlation was specifically confirmed for the DCB precursor. Particularly, it was observed that increasing the degree of hydroxylation at the catalyst's surface resulted in a greater yield of EPFRs for DCB230. The unexpected finding was the indifferent behavior of MCP230 EPFRs to the surface morphology of the catalyst, i.e., no matter whether copper oxide nanoparticles are distributed densely, sparsely, or completely agglomerated. The yields of MCP230 EPFRs remained consistent regardless of the catalyst type or preparation protocol. Although current experimental results confirm the early model for the generation of DCB EPFRs (i.e., the higher the hydroxylation is, the higher the yield of EPFRs), it is of utmost importance to closely explore the heterogeneous alternative mechanism(s) responsible for generating MCP230 EPFRs, which may run parallel to the conventional model. In this study, detailed spectral analysis was conducted using the EPR technique to examine the nature of DCB230 EPFRs and the aging phenomenon of DCB230 EPFRs while they exist as surface-bound o-semiquinone radicals (o-SQ) on copper sites. Various aspects concerning bound radicals were explored, including the hydrogen-bonding tendencies of o-semiquinone (o-SQ) radicals, the potential reversibility of hydroxylation processes occurring on the catalyst's surface, and the analysis of selected EPR spectra using EasySpin MATLAB. Furthermore, alternative routes for EPFR generation were thoroughly discussed and compared with the conventional model.

Correction: The impact of pet ownership on healthcare access and utilization among people with HIV.

[This corrects the article DOI: 10.1371/journal.pone.0292658.].

Alarming patterns of moderate and high-risk alcohol use among transgender women in Goiás, Central Brazil.

Background: Scant studies have examined alcohol consumption among transgender women in Latin America. This cross-sectional study estimated the prevalence and associated factors of risky alcohol use among transgender women in Goiás, a state located in the center of Brazil. Methods: Participants were 440 transgender women (median age = 35 years, interquartile range = 9) recruited through respondent-driven sampling. All participants were interviewed about sociodemographic characteristics, violence, and risk behavior. Alcohol use was assessed using the alcohol use disorders identification test (AUDIT). An AUDIT score greater than or equal to eight was considered as risky alcohol consumption. Logistic regression analysis was used to examine predictors of risky alcohol use, and p-values <0.05 were considered significant. Results: The majority were young, single, sex workers. Most transgender women had used alcohol in the previous year (85.7%), and more than half (56.6%) reported binge drinking and risky alcohol consumption (60.2%). There was a high overlap between sexual behavior, drugs, and alcohol use. Using alcohol during sex (adjusted odds ratio [aOR]: 2.9; 95% confidence interval [CI]: 1.7-4.8), cocaine/crack use (aOR: 2.3; 95% CI: 1.5-3.7) and having a drug user as a sexual partner (aOR: 2.9; 95% CI: 1.5-5.9) were independently associated with risky alcohol consumption. Conclusion: Alcohol consumption was highly prevalent, and drugs seem to play an important role in risky alcohol consumption among transgender women Goiás. These findings support stakeholders to promote intervention strategies to reduce this pattern of alcohol consumption and reduce the burden of substance use disorders among transgender women.

Associations of Intimate Partner Violence and Drug Use on Viral Suppression Among Women Living With HIV in South Florida: A Secondary Analysis.

ABSTRACT: Suboptimal viral suppression is associated with worse outcomes and increased HIV transmission among women with HIV (WWH). Based on syndemic theory, we hypothesized that women exposed to recent intimate partner violence (IPV) and current drug use would be most likely to have suboptimal HIV viral suppression. We analyzed baseline data from a longitudinal clinical trial (WHAT-IF? Will Having Alcohol Treatment Improve My Functioning?) that enrolled WWH from Miami, FL, who reported heavy drinking. Bivariate logistic regression was done, mean age was 48 years ( n = 194; SD : 8.7), 40% had current drug use (other than alcohol), and 14% reported recent IPV. WWH who reported both IPV and drug use had the highest rate of suboptimal viral suppression (45%), but these differences were not statistically significant. The high rates of suboptimal viral suppression, drug use, and IPV suggest a need to include screening for IPV in clinical guidelines related to HIV care in women.

Demographics, Trends, and Clinical Characteristics of HIV Pre-Exposure Prophylaxis Recipients and People Newly Diagnosed with HIV from Large Electronic Health Records in Florida.

Florida is one of the HIV epicenters with high incidence and marked sociodemographic disparities. We analyzed a decade of statewide electronic health record/claims data-OneFlorida+-to identify and characterize pre-exposure prophylaxis (PrEP) recipients and newly diagnosed HIV cases in Florida. Refined computable phenotype algorithms were applied and a total of 2186 PrEP recipients and 7305 new HIV diagnoses were identified between January 2013 and April 2021. We examined patients' sociodemographic characteristics, stratified by self-reported sex, along with both frequency-driven and expert-selected descriptions of clinical conditions documented within 12 months before the first PrEP use or HIV diagnosis. PrEP utilization rate increased in both sexes; higher rates were observed among males with sex differences widening in recent years. HIV incidence peaked in 2016 and then decreased with minimal sex differences observed. Clinical characteristics were similar between the PrEP and new HIV diagnosis cohorts, characterized by a low prevalence of sexually transmitted infections (STIs) and a high prevalence of mental health and substance use conditions. Study limitations include the overrepresentation of Medicaid recipients, with over 96% of female PrEP users on Medicaid, and the inclusion of those engaged in regular health care. Although PrEP uptake increased in Florida, and HIV incidence decreased, sex disparity among PrEP recipients remained. Screening efforts beyond individuals with documented prior STI and high-risk behavior, especially for females, including integration of mental health care with HIV counseling and testing, are crucial to further equalize PrEP access and improve HIV prevention programs.

Oral Cannabidiol Treatment Is Associated with an Anti-Inflammatory Gene Expression Signature in Myeloid Cells of People Living with HIV.

Introduction: HIV-related comorbidities appear to be related to chronic inflammation, a condition characterizing people living with HIV (PLWH). Prior work indicates that cannabidiol (CBD) might reduce inflammation; however, the genetics underpinning of this effect are not well investigated. Our main objective is to detect gene expression alterations in human peripheral blood mononuclear cells (PBMCs) from PLWH after at least 1 month of CBD treatment. Materials and Methods: We analyzed ∼41,000 PBMCs from three PLWH at baseline and after CBD treatment (27-60 days) through single-cell RNA sequencing. Results: We obtained a coherent signature, characterized by an anti-inflammatory activity, of differentially expressed genes in myeloid cells. Conclusions: Our study shows how CBD is associated with alterations of gene expression in myeloid cells after CBD treatment. Clinical Trial Registration: NCT05209867.

Depression and Anxiety Symptoms and Treatment Utilization, and Associated HIV Outcomes among Adults with HIV in Rural Florida.

Persons living with HIV (PLWH) and depression or anxiety in the rural South may have suboptimal HIV outcomes. We sought to examine the proportion of PLWH from rural Florida with symptoms of depression or anxiety, the proportion who received depression or anxiety treatment, and the relationship between untreated and treated symptoms of depression or anxiety and HIV outcomes. Cross-sectional survey data collected between 2014 and 2018 were analyzed. Among 187 PLWH residing in rural Florida (median age 49 years, 61.5%, male 45.5% Black), 127 (67.9%) met criteria for symptoms of depression and/or anxiety. Among these 127 participants, 60 (47.2%) were not on depression or anxiety treatment. Participants with untreated symptoms of depression and anxiety (OR 3.2, 95% CI 1.2-9.2, p = 0.03) and treated depression and anxiety with uncontrolled symptoms (OR 1.4, 95% CI 0.5-4.0, p = 0.52) were more likely to have viral non-suppression compared to those without depression or anxiety in an unadjusted bivariate analysis. Only the association between untreated symptoms of depression and anxiety and viral non-suppression was statistically significant, and when adjusting for social and structural confounders the association was attenuated and was no longer statistically significant. This suggests that social and structural barriers impact both mental health and HIV outcomes. Our findings support the need for increased mental health services and resources that address the social and structural barriers to care for PLWH in the rural South.

The association of depression and anxiety symptoms to three different types of activities of daily living in persons with and without HIV.

Mood disorders are highly prevalent in people living with HIV (PLWH) and represent a potential contributor to functional impairment in activities of daily living. We aimed to determine if (1) Anxiety and depression symptoms were independently associated with impairments in basic self-care, role functioning, and social functioning and (2) PLWH differentially experienced impairments due to mood symptoms compared to those without HIV. Data for this study were obtained from 150 individuals (87 PLWH, 61% male, mean age = 44) via a cross-sectional study on alcohol and HIV-associated brain dysfunction. The Beck Anxiety Inventory (BAI) and the Center for Epidemiologic Studies Depression Scale (CES-D) were used to assess anxiety and depressive symptoms. Higher anxiety symptoms were associated with role functioning impairment, while higher depressive and anxiety symptoms were each associated with social functioning impairment. As depressive symptoms increased, PLWH were 3x more likely to have impairments in role functioning compared to those without HIV. HIV status did not interact with mood symptoms to affect basic self-care or social functioning. Overall, mood symptoms are associated with different types of functional impairment, and improved management of mood symptoms could lead to improved role and social functioning.

Antiretroviral Therapy Concealment Behaviors and their Association with Antiretroviral Therapy Adherence among People with HIV: Findings from the Florida Cohort Study.

Little is known about HIV medication concealment behaviors and the effect of medication concealment on antiretroviral therapy (ART) adherence among people with HIV (PWH). This study aims to (1) to describe medication concealment behaviors and factors associated with these behaviors, and (2) assess the association between medication concealment and suboptimal ART adherence. The Florida Cohort Study enrolled adult PWH from community-based clinics around the state from October 2020 to September 2022 (n = 416, 62% aged 50+, 56% male, 44% non-Hispanic Black, 18% Hispanic). Participants responded to questions about sociodemographics, stigma, ART adherence (≥ 85%), symptoms of depression, social networks and disclosure to their networks, and actions to conceal ART to avoid inadvertent disclosure of their HIV status. Analyses were conducted using multivariable logistic regressions models. The most common concealment behavior was hiding ART while having guests over (32%), followed by removing ART labels (26%), and putting ART into a different bottle (16%). Overall, 43% reported ≥ 1 behavior. In multivariable models, depressive symptoms, incomplete disclosure of HIV to close social networks, and not having a close social network were associated with ART concealment. After adjusting for risk factors for suboptimal ART adherence, endorsing hiding medication while having guests was associated with suboptimal ART adherence (aOR 2.87, 95% CI 1.15-7.55). Taking any action and other individual behaviors were not associated. ART concealment behaviors were common but did not consistently negatively influence adherence when accounting for other factors. PWH may want to receive ART medications in ways that ensure privacy and reduce the risk of inadvertent disclosure.

Assessing HIV-related stigma in the clinical setting: are providers in Florida interested?

HIV-related stigma is a key contributor to poor HIV-related health outcomes. The purpose of this study is to explore implementing a stigma measure into routine HIV care focusing on the 10-item Medical Monitoring Project measure as a proposed measure. Healthcare providers engaged in HIV-related care in Florida were recruited. Participants completed an interview about their perceptions of measures to assess stigma during clinical care. The analysis followed a directed content approach. Fifteen participants completed the interviews (87% female, 47% non-Hispanic White, case manager 40%). Most providers thought that talking about stigma would be helpful (89%). Three major themes emerged from the analysis: acceptability, subscales of interest, and utility. In acceptability, participants mentioned that assessing stigma could encourage patient-centered care and serve as a conversation starter, but some mentioned not having enough time. Participants thought that the disclosure concerns and negative self-image subscales were most relevant. Some worried they would not have resources for patients or that some issues were beyond their influence. Participants were generally supportive of routinely addressing HIV-related stigma in clinical care, but were concerned that resources, especially to address concerns about disclosure and negative self-image, were not available.

Trajectories of Pre-Exposure Prophylaxis (PrEP) Adherence Among Commercially Insured Individuals.

We used group-based trajectory models to identify four distinct trajectory patterns of adherence to pre-exposure prophylaxis (PrEP) among 20,696 users. Only 44.5% were consistently PrEP adherent, with younger age, being female, or having substance use disorder or depression associated with early discontinuation. Public health efforts are needed to improve PrEP adherence.

Modeling within-session dynamics of categorical and item-memory mechanisms in pigeons.

Past studies have shown that pigeons can learn complex categories and can also remember large numbers of individual objects. In recent work, Cook et al. Psychonomic Bulletin & Review, 28, 548-555, (2021) provided evidence that pigeons may use a dynamic combination of both category-based information and item-specific memorization to solve a categorical variation of the mid-session reversal (MSR) task, which is an influential task for exploring the nature of temporally organized behaviors in animals. To provide greater insight into these pigeons' behaviors, in this article we developed and investigated different computational models and their variations to account for these data. Of these, two models emerged as good candidates. One was a multinomial-processing-tree categorization/memory model, formalizing the two-process mechanism initially proposed by Cook et al. Psychonomic Bulletin & Review, 28, 548-555, (2021). The second was a new object/time-coding model, which posits the storage of object-specific memories with an additional within-session time code and assumes that a basic stimulus generalization process underlies the pigeons' choice behavior. Both provided high-quality fits to the published sets of training and transfer data collected in the categorical MSR task. These computational efforts give deeper insights into the theoretical mechanisms underlying the temporal and sequential structure of behavior in animals and stimulate future empirical research further revealing the organization of the pigeons' cognitive processes.