OA01-06 LB. HIV-1 plasma RNA and risk of HIV-1 transmission

Background: Non-sterilizing HIV-1 vaccines may provide public health benefits if they significantly reduce plasma HIV-1 RNA, thus potentially reducing infectiousness. Quantification of reduction in plasma HIV-1 RNA needed to decrease HIV-1 transmission is useful for design of efficacy trials of candidate HIV-1 vaccines. We modeled the relationship between plasma HIV-1 RNA and HIV-1 transmission using data from a prospective study of African heterosexual HIV-1 serodiscordant couples. Methods: 3408 HIV-1-infected participants with CD4 counts ≥250 cells/mm3 enrolled in the Partners in Prevention HSV/HIV Transmission Study and their partners were followed for ≤24 months. HIV-1 transmission events were assessed for viral genetic linkage within the enrolled partnership by determining HIV-1 env and gag sequences from partners. The relationship between plasma HIV-1 RNA over time and risk of genetically linked HIV-1 transmission was evaluated with a Cox model with a natural cubic spline. Results: 84 post-enrollment linked HIV-1 transmissions were observed. HIV-1 incidence increased rapidly and non-linearly with higher plasma HIV-1: from 0.53 transmissions per 100 person-years for plasma HIV-1 RNA 1,000,000 copies/mL (p<0.0001). Baseline HIV-1 RNA in men was, on average, 0.4 log10 higher than in women; no significant difference in risk of transmission for a given HIV-1 level was observed between men and women (p = 0.17). Given the distribution of plasma HIV-1 RNA in this population of stable cohabiting couples, our modeling predicts that a 0.74 log10 reduction in average plasma HIV-1 RNA in the population would be required for a 50% reduction in HIV-1 transmission risk. Conclusion: This analysis provides a detailed description of the relationship between plasma HIV-1 RNA and risk of heterosexual HIV-1 transmission. These findings suggest targets for reduction in HIV-1 RNA for use in evaluating non-sterilizing HIV-1 vaccine candidates in HIV-1 infected persons to reduce risk of heterosexual HIV-1 transmission

Demystifying the Relationship Between Confidence and Critical Thinking in Mathematics among Preservice Teachers in West Philippines

Mathematical confidence and critical thinking are essential in preparing preservice teachers. Thus, this study explored the perceived confidence and critical thinking levels in mathematics of elementary and secondary preservice teachers. A descriptive-correlational-comparative research design was employed, with a sample of 107 randomly selected preservice teachers enrolled in the Bachelor in Elementary and Secondary Education programs of a state university in West Philippines. The study used arithmetic mean, standard deviation, Spearman’s rank-order correlation, and independent samples t-test to analyze and draw conclusions from the data. The findings revealed that the preservice teachers have high confidence and critical thinking skills. Their program significantly correlates with their perceived critical thinking and confidence level. Besides, the preservice teachers’ confidence levels and perceived critical thinking skills significantly correlate. Further analysis found significant confidence and critical thinking differences favoring the secondary over the elementary preservice teachers. These findings provide insights that would benefit mathematics educators in providing priority programs to enhance the preparation of future math teachers

Problem-Solving Difficulties, Performance, and Differences among Preservice Teachers in Western Philippines University

The ability to solve problems is a prerequisite in preparing mathematics preservice teachers. This study assessed preservice teachers’ problem-solving difficulties and performance, particularly in worded problems on number sense, measurement, geometry, algebra, and probability. Also, academic profile differences in the preservice teacher’s problem-solving performance and common errors were determined. A descriptive-comparative research design was employed with 158 random respondents. Data were gathered face-to-face during the first semester of the school year 2022-2023, and data were analyzed with the aid of jamovi software, ensuring ethical measures. Overall findings revealed that the preservice teachers experienced average difficulty in solving problems. The low performance of the preservice teachers on the given problems was also demonstrated. Further analysis revealed a significant difference between the preservice teachers’ problem-solving performance based on their subject preference and program. Moreover, the error analysis revealed that the preservice teachers incurred comprehension errors in misrepresentation, misinterpretation, and miscalculation. These results will serve as a measure for policymakers and curriculum developers of the teacher education institution concerned to make relevant enhancements to the math courses offered in the elementary and secondary education programs

Subjective impressions of minority group representation in the media: A comparison of majority and minority viewers' judgments and underlying processes

Consumers' judgments of the frequency with which members of an ethnic minority are represented in advertisements can depend on the processing strategies they employ both at the time the ads are first encountered and at the time the judgments are reported. These strategies, in turn, can depend on whether the consumers personally belong to the minority group in question. European American and African American participants received a series of advertisements that varied in terms of the relative numbers of Black and White models that were portrayed. European Americans overestimated the number of Black models that appeared in the ads when the actual incidence of these models was low, but this overestimation decreased (and thus they became more accurate) as the number of ads containing these models increased. In contrast, African Americans were accurate when only a small number of Black models were presented, but became less accurate as the actual incidence of the models became greater. European Americans apparently based their estimates on the ease of recalling individual instances at the time of judgment, whereas African Americans appeared to perform an online tally of the number of Black models shown at the time they encountered them

Meningiomas and hormonal receptors: immunohistochemical study in typical and non-typical tumors Meningiomas e receptores hormonais: estudo imuno-histoquímico em tumores típicos e não típicos

The authors assessed 116 cases of meningiomas classified as typical, atypical and anaplastic and they used an immunohistochemical technique for estrogen and progesterone receptors attempting to determine if there is any difference between typical and non-typical tumors in relation to hormone receptors. The immunohistochemical technique to estrogen receptors was negative in all meningiomas studied. Progesterone receptors were detected in 58.3% of typical, and in 48.2% of non-typical meningiomas. This difference was not statistically significant. However, individually considering the criteria used for selection of non-typical tumours, those that concurrently displayed brain invasion and increased mitotic activity or necrosis, as well as the summation of those three features, were predominantly negative for progesterone receptors (respectively p=0.038; p=0.001; and p=0.044). The authors conclude that estrogen receptors were not present in meningiomas; that progesterone receptors in isolation are not enough to predict a higher tumoral malignancy but can be useful associated with other histological features.<br>Os autores avaliam 116 meningiomas classificados em típicos, atípicos ou anaplásicos usando técnica imuno-histoquímica para receptores de estrógeno (ER) e progesterona (PR) com o objetivo de determinar se existe diferença entre tumores típicos e não típicos em relação aos receptores hormonais. Todos os tumores estudados foram negativos para ER. Os receptores de progesterona foram detectados em 58,3% dos meningiomas típicos e em 48,2% dos tumores não-típicos. Essa diferença não foi estatisticamente significativa. Entretanto, considerando os critérios utilizados para seleção dos não-típicos, os tumores que apresentavam, de forma concomitante, invasão do sistema nervoso central e aumento da taxa mitótica ou necrose, bem como a soma das três características, foram predominantemente negativos para PR (p=0,038; 0,01 e 0,044, respectivamente). Os autores concluem que: ERs não estão presentes em meningiomas; PRs estão presentes na maioria dos meningiomas; a negatividade para PR isoladamente não é suficiente para predizer maior malignidade mas pode ser útil se associada a outras características histológicas