Our Fellows

James Croker, PhD

Postdoctoral Scholar

J. Alton Croker III, PhD, received his doctorate in Health Services & Policy focusing on cannabis policy, health outcomes, and health disparities. He graduated from the University of Iowa in 2021, where he served as a research investigator for the Cannabis and End-of-Life Study, along with research associate roles within the RUPRI Center. He previously worked in public affairs at GLAD (GLBTQ Advocates & Defenders), an impact litigation firm focusing on social equity for LGBTQ persons, people living with HIV/AIDS, and their families. He also held research and grant management roles at Fenway Health Institute and the SARDI Center for Interventions at Wright State University Boonshoft School of Medicine, working to meet the health needs of communities of color. With a focus on health and social equity for Black people and LGBTQ youth of color, he also served in policy and community engagement roles with the National Black Treatment Advocates Network.

As a postdoctoral fellow at UCSF, Dr. Croker hopes to investigate adverse health effects of cannabis use, the ‘reinvestment’ of cannabis revenues by states and local governments into communities of color disproportionately impacted by the War on Drugs, and the role of the cannabis industry in the policy making process.

Sheiphali Gandhi, MD

HS Asst Clinical Professor

Sheiphali Gandhi, MD, is a pulmonologist specializing in occupational and environmental respiratory disease. She graduated from Indiana University School of Medicine in 2012. She went to the University of Minnesota for her internal medicine residency and global health chief residency during which she received her Certificate in Tropical Medicine through the Center of Disease Control and American Society of Tropical Medicine and Hygiene. She completed her fellowships in Pulmonary and Critical Medicine at Northwestern University and Occupational and Environmental Medicine at the University of California San Francisco. During this time, she specialized in occupational pulmonology namely pneumoconioses with projects in coal mine and silica dust respiratory disease surveillance. 

As a postdoctoral fellow at UCSF, Dr. Gandhi plans to investigate the environmental and occupational risk factors for mesothelioma in the collaboration through a case-control study in collaboration with the California Department of Public Health and the California Cancer Registry. Additionally, she will conduct a feasibility study of the creation of a rapid case ascertainment and patient contact study utilizing natural language processing techniques using electronic pathology records. 

Dian Gu, PhD

Postdoctoral Scholar

Dian Gu, PhD, received her doctorate in Health Economics/Health Services Research from the University of Texas Health Science Center at Houston. Along with her PhD study, she was a PhD trainee in MD Anderson Cancer Center. In that role, she gained experience in applying health economics to cancer research, collaborating on manuscripts with clinicians on multiple projects concerned with cancer patients’ healthcare utilization, expenditures, and health outcomes.

After finishing her PhD, she joined the Institute for Health & Aging at the University of California, San Francisco in 2019. In the work here, she mainly performs data analyses and collaborates on manuscripts with professors on a wide range of tobacco economics research projects. For example, she analyzed the National Health Interview Survey (NHIS), Medical Expenditure Panel Survey data (MEPS) and California Health Interview Survey (CHIS) to evaluate the economic impact of a $2-per-pack cigarette tax increase due to Proposition 56 on smoking behaviors, healthcare costs, and the financial burden on low-income people in California.

As a postdoctoral fellow, Dr. Gu is interested in integrating both cancer and tobacco research. Her current research areas of interest include 1) estimating economic costs attributable to tobacco use of cancer and other tobacco-related illnesses; 2) examining the role of tobacco use in cancer prevention and development; 3) evaluating the economic impact of different tobacco control policies on the financial burden on vulnerable populations.

Eileen Han, PhD

Postdoctoral Scholar

Eileen Han, PhD, received her doctorate in Communication from the Annenberg School for Communication, University of Pennsylvania. During and after her PhD studies, she mainly conducted qualitative research about social media, with a focus on collective memory and social activism. She published a book about social media and collective memory in China, which was an expansion of her dissertation research. Since then, she has been expanding her research to look at social media in many other contexts, including health and medicine, in which she is primarily interested in the use and understanding of expertise and authority in the digital age. Her current research mainly focuses on the public discourses on social media about health issues, including how Twitter users talk about doctors and the medical community during the COVID-19 pandemic. This year, she has also received a MS degree in Information from the University of Michigan, where she had trainings in programming, data analysis, natural language processing and machine learning. 

Dr. Han is very excited to join the fellowship program at CTCRE, where she would like to combine her qualitative and computational skills to explore promising topics in the tobacco regulatory field. She will focus on how the public discussions on major social media platforms about new tobacco products and personal experiences could inform policymaking and regulation. She is also interested in looking at different types of authorities and expertise in this process. She would also like to study various forms of texts related to tobacco marketing and control. 

Sabrina Islam, PhD, MS

Postdoctoral Scholar

Sabrina Islam, PhD received her doctorate in Public Health (Social and Behavioral Sciences) with a Graduate Certificate in Gender, Sexualities, and Women’s Studies from the University of Florida. Prior to joining the CTCRE in August 2022, she completed a training fellowship in prevention science and alcohol research at the University of California, Berkeley. Dr. Islam is interested in qualitative and mixed-methods approaches to studying differential patterns of risk associated with substance use and structural levels of stigma among sexual and gender minority populations. Her most recent published work pivots towards young people who co-use tobacco, cannabis, and alcohol.

Karla Llanes, PhD

Postdoctoral Scholar

Karla Llanes, PhD, received her doctorate in Health Psychology at the University of Texas at El Paso (UTEP). During her PhD training, she worked for A Smoke Free Paso del Norte, a west Texas, southern New Mexico, and Juarez, Mexico regional initiative targeting tobacco control in adolescents and adults. She has also taught several Statistics courses and Motivation and Emotion courses at the University of Texas at El Paso. Her research interests are in judgment and decision-making processes in the context of health-related decisions (e.g., vaccination decisions, driving under the influence of alcohol, marijuana use, and novel tobacco use). Her goal is to identify judgment biases that distort risk communications and risk perceptions and, eventually, impact individuals' decisions to engage in health-threatening and health-promoting behaviors. She currently studies individual’s motivation for initiating and continuing drug use.

   As a postdoctoral fellow, Dr. Llanes plans on continuing her research investigating predictors of drug use, drug use initiation, and cessation. She is particularly interested in investigating risk factors associated with tobacco use, novel tobacco use, and co-use (e.g., e-cigarette and alcohol use). Specifically, she would like to identify why individuals make harmful health decisions. By understanding what leads to harmful real-life decisions, then she can help develop interventions that may help people change for the better.

Joanne Lyu, PhD

Postdoctoral Scholar

Joanne Lyu, PhD, received her PhD in Communication from The Chinese University of Hong Kong. Prior to joining CTCRE, she was an Assistant Professor at Macau University of Science and Technology, and most recently at The Hang Seng University of Hong Kong. During her doctoral study, Joanne won a Top Student Paper award in the Public Relations (PR) Division at the 2012 annual conference of International Communication Association (ICA). In 2017, as a principal investigator, she was awarded a Hong Kong government research grant. Joanne is excited to be a member of CTCRE. She is very much looking forward to studying the PR and marketing strategies used by the tobacco industry, and exploring the social, relational, and individual factors influencing smoking behavior and smoking cessation. Joanne is also eager to branch out into other research areas in tobacco education and control during her fellowship at CTCRE.

Seyed Mehrdad Mohammadi, MD

Postdoctoral Scholar

Mehrdad Mohammadi, MD, MPH, MA in Law and Diplomacy received his credentials in medicine, public health, law and development economics from Tehran University, Tufts University and Harvard University. He has been an adjunct professor at the School of Public Health at Tehran University teaching Justice and Public Health Law. Working with the WHO, Dr. Mohammadi has advised the Ministry of Health on International Health Regulations and the Framework Convention on Tobacco Control (FCTC). This includes projects on tobacco content and emission regulation (FCTC Articles 9 and 10), tobacco products plain packaging (FCTC Articles 11 and 13), NGO advocacy (FCTC Articles 4.7 and 12.e), smoke-free cities and campuses (Article 8), liability of the tobacco industry (FCTC Article 19), and participation in COP9 in 2021. He has founded the NGO titled An Iran Immune to Tobacco (IMAD).

Jelena Mustra Rakic, PhD

Postdoctoral Scholar

Jelena Mustra Rakic, PhD, received her PhD in Biochemical and Molecular Nutrition from Tufts University in Boston. Her dissertation was focused on elucidating the effect and mechanisms of the naturally occurring carotenoid, lycopene, on chronic obstructive pulmonary disease, lung carcinogenesis and non-alcoholic fatty liver disease. The important finding from her PhD implicated smoking-related alterations in lipid metabolism as one of main pathways leading to chronic inflammation and lung diseases development. As a postdoctoral fellow at the Center for Tobacco Control Research and Education, Dr. Mustra Rakic is interested in exploring the effects of tobacco smoking and/or vaping on biochemical properties of lipids and lipoproteins that contribute to excessive inflammation, and the risk of chronic diseases, particularly cardiovascular disease and cancer.  

Andre Luiz Oliveira da Silva, PhD

Postdoctoral Scholar

Andre Luiz Oliveira da Silva, PhD received his doctorate from Escola Nacional de Saúde Pública Sergio Arouca in 2019 with a specialization in public health. Dr. Oliveira da Silva joined the CTCRE in June 2022. As the Tobacco Center's first Briger Fellow, he anticipates spending one year in the Tobacco Control Research Fellowship both gaining from our faculty's expertise and sharing his rich experiences in tobacco control research from his homeland of Brazil. Dr. Oliveira da Silva will be mentored by Stella Bialous, DrPH, FAAN, also from Brazil. Both researchers have worked for a long time with the WHO Framework Convention on Tobacco Control and tobacco control polices.

Vira Pravosud, PhD

Postdoctoral Scholar

Vira Pravosud, PhD, received her doctorate in Epidemiology and Biostatistics from the University of Kentucky. Having obtained an undergraduate degree in Social Work & Sociology and a Master’s degree in Healthcare Management and Administration from the National University of Kyiv-Mohyla Academy in Kyiv, Dr. Pravosud came to the U.S. in 2014 as a Fulbright Scholar from Ukraine pursuing more expertise in public health research. Her dissertation focused on examining whether the use of social-networking and dating online platforms can facilitate engagement in HIV-related risk behaviors among young adult men who have sex with men. During her doctoral program, Dr. Pravosud also had the opportunity to conduct studies assessing respiratory health outcomes, including chronic obstructive pulmonary disease, lung cancer, and nontuberculous mycobacterial lung infection.

As a postdoctoral fellow, Dr. Pravosud’s research agenda will include assessment of health impacts of novel tobacco products (e-cigarettes and heated tobacco products). Additionally, she is interested in digital usage for prevention of novel tobacco products consumption, especially among youth and adolescents.