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6. U.S. Visa and Immigration Policy Challenges: Explanations for Faculty Perceptions and Intent to Leave

Author

Feeney, Mary K., Jung, Heyjie, Johnson, Timothy P., and Welch, Eric W.

Abstract

United States (US) immigration policies have increasingly focused on national security resulting in universities experiencing declines in international student applications, constraints on international scholar employment, and complications facilitating international research collaborations. The COVID-19 pandemic brought additional travel restrictions, embassy closures, and health and safety concerns that exacerbated these challenges. Science mobility is critical for science education, training, competitiveness, and innovation. Using a representative sample of US and foreign-born scientists in three STEM fields, we explore how recent visa and immigration policies have shaped research collaborations, work with students and postdoctoral scholars, and intentions to leave. We use descriptive statistics, analysis of variance, and logistic regression and find academic scientists report disruptions from visa and immigration policies; negative impacts of immigration policies on US higher education; negative effects on recruitment and retention of international trainees; and increased intentions to leave the US driven by negative perceptions of immigration policy.

Published
2023
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21. Sources of HIV information and women's HIV knowledge in Southwest Sumba Indonesia: a cross-sectional study with mediation analysis.

Author

Kurniadi, Angela, Levy, Judith A., and Johnson, Timothy P.

Abstract

Background: Despite multiple years of government HIV educational efforts, the growing trend of new cases among women in Indonesia runs parallel with their seemingly overall lack of comprehensive knowledge about HIV. A major prevention challenge for the Indonesian government lies in delivering HIV prevention education across the world's largest archipelago. This study investigates comprehensive HIV knowledge among reproductive-age women in Southwest Sumba, Indonesia, and the sources through which they report having learned about HIV along with potential mediators of the relationship between socioeconomic status (SES) and HIV knowledge. Methods: This cross-sectional study using convenience sampling recruited 159 married women ages 15–49 years old living in 4 selected church parishes in Southwest Sumba on March 12–20, 2023. The HIV Knowledge Questionnaire-18 and items from the 2017 Indonesian Demographic and Health Survey (24 total) measured the women's comprehensive knowledge about HIV. Additional items asked about sources through which the women had received information about HIV. One-way ANOVA examined differences in the level of HIV knowledge obtained through one or more information sources (healthcare providers, media, schools, and social network members). Mediation analysis investigated potential mediators of the relationship between SES and HIV knowledge. Results: Comprehensive HIV knowledge scores ranged from 0 to 21 (mean = 10.6). About 65% of the 159 women could only correctly answer 50% or less of the questions. Most incorrect answers pertained either to Mother-to-Child HIV Transmission (MTCT) or misconceptions about the virus. One-way ANOVA revealed that the mean of HIV knowledge increased as the number of informational sources increased (p <.001). Structural Equation Modelling found that social network members, healthcare providers, and the media all had significant direct effects on HIV knowledge. In addition, an indirect positive relationship between SES and comprehensive HIV knowledge was mediated by information obtained through the media and marginally through healthcare providers. Conclusions: The study's results suggest that more extensive in-depth HIV education is greatly needed to help prevent transmission among women living in small and outlying islands in Indonesia. Wider promotion of HIV information through the media and more intensively through local healthcare providers appears a promising and likely effective means to reach these women. [ABSTRACT FROM AUTHOR]

Published
2025
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22. Estimating the Prevalence of Missing Experiments in a Neuroimaging Meta-Analysis

Author

Samartsidis, Pantelis, Montagna, Silvia, Laird, Angela R., Fox, Peter T., Johnson, Timothy D., and Nichols, Thomas E.

Abstract

Coordinate-based meta-analyses (CBMA) allow researchers to combine the results from multiple functional magnetic resonance imaging experiments with the goal of obtaining results that are more likely to generalize. However, the interpretation of CBMA findings can be impaired by the file drawer problem, a type of publication bias that refers to experiments that are carried out but are not published. Using foci per contrast count data from the BrainMap database, we propose a zero-truncated modeling approach that allows us to estimate the prevalence of nonsignificant experiments. We validate our method with simulations and real coordinate data generated from the Human Connectome Project. Application of our method to the data from BrainMap provides evidence for the existence of a file drawer effect, with the rate of missing experiments estimated as at least 6 per 100 reported. The R code that we used is available at https://osf.io/ayhfv/.

Published
2020
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23. The Influence of Item Characteristics on Acquiescence among Latino Survey Respondents

Author

Davis, Rachel E., Lee, Sunghee, Johnson, Timothy P., Conrad, Frederick, Resnicow, Ken, Thrasher, James F., Mesa, Anna, and Peterson, Karen E.

Abstract

Acquiescence is often defined as the systematic selection of agreeable ("strongly agree") or affirmative ("yes") responses to survey items, regardless of item content or directionality. This definition implies that acquiescence is immune to item characteristics; however, the influence of item characteristics on acquiescence remains largely unexplored. We examined the influence of eight item characteristics on acquiescence in a telephone survey of 400 Latinos and non-Latino Whites: qualified wording, mental comparisons, negated wording, unfamiliar terms, ambiguous wording, knowledge accessibility, item length, and polysyllabic wording. Negated and ambiguous wording was associated with reduced acquiescence for the full sample as well as subsamples stratified by ethnicity and sociodemographic characteristics. This effect was strongest among younger, more educated, and non-Latino white respondents. No other item characteristics had a significant influence on respondent acquiescence. Findings from this study suggest that acquiescence may be affected by interactions between respondent and item characteristics.

Published
2020
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27. Bayesian log-Gaussian Cox process regression: applications to meta-analysis of neuroimaging working memory studies

Author

Samartsidis, Pantelis, Eickhoff, Claudia R., Eickhoff, Simon B., Wager, Tor D., Barrett, Lisa Feldman, Atzil, Shir, Johnson, Timothy D., and Nichols, Thomas E.

Subjects
Statistics - Applications
Abstract

Working memory (WM) was one of the first cognitive processes studied with functional magnetic resonance imaging. With now over 20 years of studies on WM, each study with tiny sample sizes, there is a need for meta-analysis to identify the brain regions that are consistently activated by WM tasks, and to understand the interstudy variation in those activations. However, current methods in the field cannot fully account for the spatial nature of neuroimaging meta-analysis data or the heterogeneity observed among WM studies. In this work, we propose a fully Bayesian random-effects metaregression model based on log-Gaussian Cox processes, which can be used for meta-analysis of neuroimaging studies. An efficient Markov chain Monte Carlo scheme for posterior simulations is presented which makes use of some recent advances in parallel computing using graphics processing units. Application of the proposed model to a real data set provides valuable insights regarding the function of the WM.

Published
2017
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47. Near real-time intraoperative brain tumor diagnosis using stimulated Raman histology and deep neural networks

Author

Hollon, Todd C., Pandian, Balaji, Adapa, Arjun R., Urias, Esteban, Save, Akshay V., Khalsa, Siri Sahib S., Eichberg, Daniel G., D’Amico, Randy S., Farooq, Zia U., Lewis, Spencer, Petridis, Petros D., Marie, Tamara, Shah, Ashish H., Garton, Hugh J. L., Maher, Cormac O., Heth, Jason A., McKean, Erin L., Sullivan, Stephen E., Hervey-Jumper, Shawn L., Patil, Parag G., Thompson, B. Gregory, Sagher, Oren, McKhann, II, Guy M., Komotar, Ricardo J., Ivan, Michael E., Snuderl, Matija, Otten, Marc L., Johnson, Timothy D., Sisti, Michael B., Bruce, Jeffrey N., Muraszko, Karin M., Trautman, Jay, Freudiger, Christian W., Canoll, Peter, Lee, Honglak, Camelo-Piragua, Sandra, and Orringer, Daniel A.

Published
2020
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