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This week we are excited to feature one of our faculty members, Liping Du, PhD, who is an Assistant in Biostatistics and supports the Center for Quantitative Sciences.  Read on to learn more about her work here at Vanderbilt and her interests outside of our group:

What is the focus of your research and where have your findings been published?   
I have worked in several areas of research. When I was a student working with Dr. Robert Tanner in the Chemical Engineering Department of Vanderbilt, we published 11 papers about protein purification using foam fractionation in applied biochemical and biotechnology journals, and in addition we published a book chapter. After graduation, as a biomedical researcher, I investigated the roles of Cytochrome P450 and related lipids in skin biology in Dr. Diane Keeney’s lab and we published 8 related papers in biochemistry, toxicology and pharmacology journals. Then I worked with Dr. Anthony Forster in the field of synthetic biology. We had 3 publications together, and last year a paper based on my work on in vitro synthesis of E. coli translation factor module of a minimal genome was published and 4 plasmids named after my name are in the Genbank now. In the past five years, as a biostatistician, I have collaborated with many investigators and had about 26 collaborative publications in different fields. I also had a statistical method paper in evaluating bioequivalence trials data using the evidential likelihood approach with my advisor Dr. Leena Choi in the Biostatistics Department.  

What was your inspiration to pursue a career in statistics? 
The hands on experience that I had during my graduate studies in chemical engineering making a novel plasma reactor and a photoelectric device for measuring bubble size distribution in a foam fractionation column was very fulfilling. But I found that I was most interested in the quantitative part-- mathematically modeling the chemical reaction or physical separation process based on theory and confirming the results with the measured data was exciting. I do miss this part of investigating that comes with being in a wet biomedical research lab.  Fortunately, the Vanderbilt Biostatistics graduate program was started in 2011 and I joined with one of the earliest cohorts of 8 students. The reputation of Dr. Shyr’s group led me to pursue a position in this group.  I am so lucky to be able to work on several interesting projects in  the CQS over the past several years. 

As a statistician, I love this quote:  

“…the statistician must be instinctively and primary a logician and a scientist in the broader sense and only secondarily a user of the specialized statistical techniques…” 

What makes Vanderbilt special in your experiences of collaborating with others? 
At Vanderbilt, as a statistician, you may collaborate with investigators in different fields. It is so much fun working on many different projects and it is very rewarding. As I learned more about the statistical methods in Frequentist, Bayesian, and Likelihoodist, I often wonder what role statistics (probabilistic relationship) plays in science and in life. Is it providing evidence from the data, and/or guiding our belief, and/or guiding our action using the data? Also, should I consider more the causal relationship (e.g. a DAG and causal model) more in practice than just describing associations with a probabilistic model?  These are interesting questions and will keep me pondering. 

Tell us about your life outside of Vanderbilt. Do you have a significant other? Children?  What about your hobbies? 
I am a cook at home; I truly love cooking!  I learned from my mom that as a mother I need to feed my family with healthy food and ensure that they have a good appetite at every meal. I have 3 lovely children and they are the joy of my life.  As for hobbies, both my husband and I enjoy exercise and outdoor activities.  When we have chance, we take the kids out playing sports or out to enjoy nature. I wish I could go hiking more often. I hope we will continue to live a healthy and productive life.   

Finally, what is something about you that most people at Vanderbilt still don't know about you? (Until now, of course!)
I have lived around Nashville for over 21 years and it is the place where I have stayed the longest in my life. It is truly becoming my home and I really love this city!  

This week we are excited to feature one of our postdoctoral fellows from the Center for Quantitative Sciences within the Department of Biostatistics.  Dr. Yu Wang has had experience in both bioinformatics and biostatistics and is involved in some fascinating research.  Read on to learn more...

Tell us about your current research focus. 
By developing and adopting relevant bioinformatical and biostatistical methods on NGS and clinical data, my work is mainly focused on parsing genetic, transcriptomic, and immunogenetic features associated with response to anti-PD-1 and/or anti-CTLA-4 immunotherapy in patients with malignancies, and developing biomarkers by combining different features to help discriminate patients for choosing more reasonable therapy strategy.  

It’s a very challenging and hot topic with significant breakthrough in cancer therapy. I feel excited and lucky to be involved. I set up pipelines for immunogenetic signature evaluation, immune cell composition and neoantigen prediction by integrating WES, RNAseq and SWATH-MS proteomical data. By cooperating with our collaborators, we combine multidimensional data from the somatic mutation and expression profiles, to immunogenetic features in TILs, to depict the key players associated with the response to immune checkpoint blockade therapy and clinical outcomes. 

​What was your draw to statistics and/or Vanderbilt? 
Even though I am working with a lot of biological and clinical data daily, I am still a beginner in biostatistics. I really appreciate the environment provided by our department. I can learn a lot of statistics from our colleagues, courses, workshops, etc. I realize that not only the concepts and methods but also the way of thinking in biostatistics is critical for data science. I cherish the opportunities of being surrounded by the experts, and I hope I can add the cannon into my armory.

Tell us about your publications and research findings.
My most recent first author manuscript was sent out for reviewing and in that manuscript we show that rare mutations in antigen processing machinery are associated with high mutational burden and an enhancement of predicted neoantigens, providing insights into the mechanisms of high mutation burden in some patients.  I had previously published about 20 papers in plant science before I joined VUMC. After I transferred to the biomedical research field, I participated as a co-author in several publications in biomedical/clinical journals, like Nature Genetics, NPJ Breast Cancer, JCI Insight, bioRXiv etc.  

What makes Vanderbilt special in your experiences of collaborating with others? 
It’s actually my favorite part about working in CQS/Biostatistics/VUMC. With Dr. Xu's help, I am able to be focused on a specific and challenging topic with many active collaborators who work in cancer cell biology, cancer immunology and in the clinic at VUMC. They are all immunotherapeutic experts and can provide valuable data and suggestions. I can always count on help from my colleagues in many ways and know who to turn to for help with questions I have pertaining to NGS data analysis, cloud computing, REDCap and many other areas.  The atmosphere of collaborating is critical for personal development as a researcher in interdisciplinary fields, like bioinformatics, and for trying to make efforts to study complex diseases. 

Tell us about your life outside of Vanderbilt. Do you have a significant other? Children? Pets? What about your hobbies? What are your goals for the future? 
Music, cuisine and basketball feed my body and soul. The Spurs with Tim Duncan is my favorite team. I have been married to my wife for eight years. She was my classmate in college and is currently pursuing a MS’s degree in Biostatistics. We really hope to add new members to our home soon; I had a German shepherd when I was in high school and we plan to adopt a puppy next year.  

Finally, what is something about you that most people at Vanderbilt still don't know about you? (Until now, of course!) 
Well, this is a good opportunity to explain how to pronounce my first name “Yu”. It’s totally fine for me if you say it as ‘/ju:/’, like in “Thank you”.  But if you want to know something about Chinese language or just for fun, here are tips. Some of you may know that there are many Chinese characters. Each character has a sound (some have multiple). And for each sound, there are four tones. The “u” here is a vowel which is not exist in English (that is why it’s difficult for native English speakers  and it is actually written as “ü”).  Here is a link of explaining how to pronounce it. Here is an example on YouTube.  My name is the fourth tones. Try it! 

This week's Spotlight features one of our newer staff biostatisticians, Ahra Kim.  Learn how this Southern California native ventured East to Nashville for a great opportunity in research and is now learning to brave the winters, all while providing statistical support to her collaborators here at Vanderbilt.

Tell us about the research you are involved in.
I am involved with three collaborations here at Vanderbilt. Half of my time is spent working on projects with the Caribbean, Central and South America network (CCASAnet) for HIV epidemiology. It consists of HIV clinical sites from seven countries in Latin America, and is also a member of a larger consortium, International Epidemiologic Databases to Evaluate AIDS (IeDEA). In one study, we are comparing outcomes such as mortality, retention in care, and timing of antiretroviral therapy initiation in HIV infected adults with and without tuberculosis. We have recently submitted several abstracts to a conference and are currently working on additional analyses for manuscripts.

My two other collaborations are with the Department of Psychiatry and Center for Biomedical Ethics. For one project in Psychiatry, we are interested in assessing how catatonia and delirium affect survival in critically-ill patients. For Biomedical Ethics, we have been trying to better understand characteristics of patients needing ethical consults for controversial topics like organ donation or treatment decision making, as well as practice patterns of clinicians when it comes to these issues. I am grateful to be working on such a wide range of interesting projects.

What was your draw to statistics and/or Vanderbilt? 
I was drawn to statistics in a non-traditional way since I have a social science background. I enjoyed doing research, but many of my classes as an undergraduate involved secondary research and I wanted to do something more hands-on. I was fascinated when I took a course in biostatistics, which was my first exposure to learning R programming. This encouraged me to pursue a master’s degree in biostatistics. Joining the Department at Vanderbilt was an amazing opportunity for me as a new graduate, so I relocated from California.

What lessons have you learned from being a biostatistician?
Though I haven’t been a biostatistician for very long now, I’ve learned that being organized and transparent is key. Sometimes projects pause and resume months or even years later, so it’s helpful to clearly document everything and practice reproducibility to avoid confusion and save time in the long run.

What makes Vanderbilt special in your experiences of collaborating with others?
The collaboration opportunities here have been wonderful. Everybody has been very kind and respectful, and view statisticians as valuable team members. I also appreciate the diverse resources and how there are so many experts in various fields that you can learn from, especially if you encounter a difficult problem in an area you may not be familiar with.

Tell us about your life outside of Vanderbilt. Do you have a significant other? What about your hobbies?
I have been engaged to my fiancé for almost a year now and will be getting married next spring. We both moved here from California. Outside of work, I enjoy a variety of hobbies including hiking, playing tennis, and practicing yoga. I also like to see live music performances, visit cool galleries or exhibits, and occasionally attend sporting events.

Finally, what is something about you that most people at Vanderbilt still don't know about you?
Prior to moving to Nashville, I lived in an inland region of Southern California (Inland Empire) where summer temperatures can reach highs of 116 degrees Fahrenheit. Winters are usually mild with highs in the 60s. Coming to Nashville, I was shocked to see temperatures drop to single digits last winter. Though I’ve been here for a year and half now, I still haven’t acclimated fully to the cold!

This week's spotlight features one of our amazing staff biostatisticians, Samuel Nwosu.  Read on to learn more about his work and contributions to medical research through biostatistics . . . 

What is your research focus and what have been the major findings so far in your research? 
My main research collaboration has been working with the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) clinical trial group.  This has been a 6 year ongoing NIH grant funded study, with a primary goal of determining whether an invasive (INV) strategy of routine early cardiac catheterization will reduce the incidence of major adverse cardiovascular death as compared to an initial conservative (CON) medical therapy approach.  The study spans across 38 countries with over 300 sites enrolling patients.  This is a great team to be part of, there are seven principle collaborators and 16 collaborating research institutes, all having vast knowledge and experience in cardiovascular research. 

The study is scheduled to be completed towards the end of 2019 and we are currently working to finalize the main manuscripts.  In July of this past year, while outlining the methods and procedures of the trial, our study group did publish the ISCHEMIA Design Paper in the American Heart Journal (AHJ) which was a great accomplishment.  

Our group is also working on a ancillary ISCHEMIA trial called the Chronic Kidney Disease (CKD) trial.  The primary objective of this trial is to determine whether an invasive strategy of cardiac catheterization will reduce the composite endpoint of death or nonfatal myocardial infarction in patients with stable ischemic heart disease and advanced chronic kidney disease.  This study is also a multinational trial including 30 countries and over 100 sites.
With ischemia being one of the leading causes in heart disease, its great knowing that this research can change how they diagnose and treat this condition as we move into the future.


What was your draw to statistics and/or Vanderbilt?
It was almost serendipitous how I got into the field of biostatistics.  I have somewhat always had an affinity for math and how it relates to everyday life.  I graduated with an undergraduate degree in mathematics, uncertain which career field I should pursue with my degree.  I researched different fields from accounting to economics, then by chance one of my undergraduate professors asked me if I liked statistics and suggested I look into the field of biostatistics.  As I researched the more about biostatistics I saw how I could bridge my background in mathematics with statistics and apply it to the field of health research.  Upon finishing my last semester in graduate school, my advisor forwarded me the job opening for a biostatistician II position within Vanderbilt's biostatistics department, I applied and I was able to start my career as a biostatistician.


What makes Vanderbilt special in your experiences of collaborating with others?
What I enjoy about my job is the opportunity to work with so many talented people and the ability to be involved in cutting edge research.  I've been able to work on a variety of different collaborations from PTSD research to multinational clinical trials.  I like the fact that knowing the research I am involved with can enrich the scientific world and benefit people at the same time.  Plus, it is also gratifying that I work in a department that fosters growth and high importance on continuing education.  I've been able to grow as a biostatistician due to working in such a great environment.


Tell us about your life outside of Vanderbilt.
I am married to Brionni Nwosu, a professor at the Relay Graduate School of Education.  We have two beautiful girls named Kanaya (4 years old) and Kalia (15 months old) who keep our lives filled with joy and excitement.  As a family we enjoy spending time playing at the park, visiting the animals at the zoo, or viewing all the sea and water creatures at the aquarium.


Finally, what is something about you that most people at Vanderbilt still don't know about you?
I enjoy the occasional adventurous/extreme activity from time to time- whether it is zip lining, scuba diving, bungee jumping, high speed Go-Karting, or off-roading on dune buggies, I'm game.
 

We have a new staff member onboard!  Elizabeth McNeer recently joined our group as a Biostatistician II.  Read on to learn more about her studies and interests here:

What is your area of focus?
I’m just starting out as a biostatistician, so I don’t have much research experience yet. My master’s thesis work under the direction of Dr. Dandan Liu focused on evaluating the impact of various chart review strategies using electronic health record data in the context of risk prediction modeling. I currently work with researchers in the Vanderbilt Center for Child Health Policy where I’m involved with various projects that focus on improving the well-being of children. I have ongoing projects dealing with topics such as hepatitis C testing in infants and mechanical ventilation in the neonatal intensive care unit.

What was your draw to statistics and/or Vanderbilt? What has served as the pathway to your position?
As an undergraduate, I majored in math and biology, so I wanted to find a career that would combine both of my interests. I also had an interest in the medical field, so the biology courses that I chose to take were the same courses that the pre-med majors took. During the summer after my junior year of college, I attended a Summer Institute for Training in Biostatistics program at Emory University. After this program, I knew that I wanted to pursue a graduate degree in biostatistics. I came to Vanderbilt in 2016 after graduating from Mississippi College, and I earned an MS in Biostatistics in the summer of 2018. Because of my interest in the medical field, I knew that I wanted to work at a medical center like Vanderbilt, so I’m excited to now be working in the same department where I spent two years as a student!

What makes Vanderbilt special in your experiences of collaborating with others?
I’ve found that my collaborators treat me like a valuable part of the group and want me involved in the entire project, not just the parts involving statistical analysis. My collaborators value the work that I do, which makes coming to work enjoyable. I’ve also been encouraged to continually learn and apply new skills to the projects that I work on.

Tell us about your life outside of Vanderbilt.
After being in school most of my life, I’m really enjoying not having constant homework and studying to do! I enjoy reading, watching Netflix, playing board games, and hiking every once in a while. I attend The Church at Avenue South, and I also tutor math on the weekends. Also, I very much enjoy Jeni’s ice cream.

Finally, what is something that most people at Vanderbilt still don’t know about you?
Long before I took my first statistics class or knew I would have a career in statistics, my dad bought me a baseball score book and showed me how to keep baseball statistics. In elementary and middle school, I would keep stats for my brother’s Little League teams just for fun. Keeping stats helped me understand and appreciate baseball, and I still enjoy going to an occasional baseball game.

Next up in the spotlight is one of our Senior Project Managers in the Center for Quantitative Sciences, Mr. David Biagi .  Learn more about his role on the team and how he may find favor with a four-legged creature in the coming year . . .

Tell us about your group and role within the CQS IT team.
Our team in the Collaborative Studies Coordinating Center provides database and development support to a wide range of research projects. Our goal is to remove technological barriers for our collaborators. Currently we maintain a wide variety of projects for international research groups, including virtual bio-repositories, clinical trial management systems, and outcome aggregation systems. We hope to continue to enable science-at-scale by helping researchers pool their data, resources, and efforts.

What drew you to Vanderbilt and what has been your experience working in a collaborative environment such as this?
I was attracted to Vanderbilt by the personal recommendation of several colleagues. That trust was not misplaced, as it has been a great place to build a career over the last ten years. I have always felt like my input was valued and appreciated the way I have been enabled to pursue and achieve goals I've suggested in support of the department's efforts.

Tell us about your life outside of Vanderbilt. Do you have a significant other? Children? Pets? 
I'm married to my high school sweetheart and we have four daughters ages six months to seven years old. There's a long standing family debate raging over whether or not we should get a dog. I stand alone in opposition and I plan to lose this debate sometime next year.

Meet one of our newest faculty members, Dr. Simon Vandekar, an Assistant Professor in the Department of Biostatistics.  He is a great addition to our group and it's a pleasure to get to know him.

What are your research interests and what is the focus of your research? What have been the major findings so far?  
My statistical research develops inference procedures for high-dimensional data with a particular focus on neuroimaging data. This research has been published in Biostatistics, Neuroimage, and JASA. My collaborative research studies how the brain changes through development and how it is affected in psychiatric disorders. This work has been published in the Journal of Neuroscience, Nature Communications, and Science. My research has relied on family-wise error rate, spatial extent inference, and semiparametric procedures and I would like to begin to develop nonparametric procedures that control the false discovery rate. I am also interested in high-dimensional measures of replicability and the stability of findings across varying preprocessing parameters.

Tell us about any honors you have received, awards you have won or any significant publications you've had.
I was awarded the Saul Winegrad Oustanding Dissertation in my graduate group when I graduated in May 2018. My most recent first author publications were in JASA, Biostatistics, and the Journal of Cerebral Blood Flow and Metabolism.

What was your draw to statistics and what are some of your goals?
I realized I loved statistics after working in a neuroimaging lab after graduation with a BS in psychology. The goal of my research is to develop statistical tools that can be immediately applied to real world problems. I am most interested in semiparametric methods to do this.

Can you share the status of any of your past students?  What is your philosophy about teaching or research?
I haven’t mentored any students, but I look forward to the opportunity! I personally learn mathematical or statistical tools best when I use them to solve problems in my research. I think statistical methods should try to make realistic assumptions about the data and that the analysis approach should be determined by particular questions or hypotheses.

What makes Vanderbilt special in your experiences of collaborating with others? What are your thoughts on controversial statistical topics such as adjusting the p-value for multiple comparison, the choice between Bayesian, likelihood, or frequentists, ethical issues, etc.?
The collaborators I’ve worked with here seem extremely focused on the wellbeing of their patients, which makes working with them more rewarding. My work is in multiple comparisons adjustment and I see it as a way for understanding the amount of bias induced by looking at hundreds of thousands of variables, but I don’t think that we should use hard thresholds to decide about the unknown state of the world. Two studies that presents results with and without adjustment are equally valid, but the first provides more evidence against the null hypothesis. I am interested in learning more about semiparametric likelihood and Bayesian methods. I like the probabilistic statements the Bayesian philosophy affords but have an aversion to priors or heavily parametric models because I’m not sure how assumption violations affect the bias and interpretation.

Tell us about your life outside of Vanderbilt. Do you have a significant other? What about your hobbies? 
My spouse currently lives in Houston with our two dogs (a dachshund and a basset-lab mix), where she is doing an internship, but she will get to move here soon! I like hiking, camping, running and visiting the many delicious breweries we have in Nashville. I also like foraging for mushrooms.

Finally, what is something about you that most people at Vanderbilt still don't know about you? (Until now, of course!)
My wife and I dabble in extreme sports. My favorite was hang gliding, but we also tried sky diving and go scuba diving not too infrequently.

This week we are excited to feature Quanhu "Tiger" Sheng who is one of our Research Assistant Professors in the Department of Biostatistics and also the Technical Associate Director of VANGARD.  Learn more about his work and interests here at Vanderbilt as you read on below:

What is your area of interest and what have been your findings? What are the next steps for your research?
I like coding and I always believe the algorithm development and/or paper should not be the end of our bioinformatics/biostatistics research, therefore I  focus on developing algorithms and implement software to help the lab, the collaborator and the research community.

For example, I have worked on TurboRawToMGF, BuildSummary and ProteomicsTools for proteomics research, NGFPERL, GLMVC and TIGER for next generation sequencing analysis. Almost all of those findings have come from my very close collaborations with various wet lab researchers. The manuscripts produced have been published in journals such as  Rapid Commun Mass Spectrom, J Proteome Res, Genomics and Journal of Extracellular Vesicles. Currently, I am very interested in large scale next generation sequencing analysis using cloud computing. I hope I can provide some software solutions to help people who want to migrate the analysis from a local cluster to a cloud platform.



Tell us about some of your achievements-- any publications, leadership positions, and/or committees you have served on.
I have published 83 peer-reviewed papers with the majority of those being related to qualitative and quantitative proteomics, glycomics, next generation sequencing and multi-omics data integration. I am currently the Technical Associate Director of VANGARD (Vanderbilt Technologies for Advanced Genomics Analysis and Research Design).  In addition to that, I am leading a group to develop the NGS analysis framework in ACCRE which can dramatically improve the reproducibility and efficiency of data analysis.

What was your draw to the field of statistics and what are your goals?
Actually, my major was bioinformatics, but I have learned so much since joining the Center for Quantitative Sciences and then the Department of Biostatistics. I have learned that even with the very basic t-test, I need to make sure that the data truly supports the assumptions. I really believe that statistics is an essential part of both basic science and clinical research, and that the Department of Biostatistics will play more important roles in the Vanderbilt research community in the near future. Currently, I define myself as an entry-level biostatistician and an expert in bioinformatics. My goal is to apply my knowledge in precision medicine to help doctors and patients.

Can you share the status of any of your past students? What is your best advice for aspiring statisticians? 
I haven't had any students yet but I have guided a lot of our postdocs and staff members at various stages.  I really enjoy sharing my experience with people.

For those aspiring statisticians, I hope they can also work with some technical fields, such as code management, test driven development and even cloud computing. Those fields will make their research more robust, more efficient, and most importantly, more reproducible.

What makes Vanderbilt special in your experiences of collaborating with others? 
When I joined the team in 2012, I immediately felt the closeness from the collaboration between the basic science groups and clinical groups, and the discussions between the bioinformaticians and biostatisticians were amazing. It felt like a new window had opened up for me at that time. I have enjoyed this environment and getting the chance to work with all of the experts from different fields.  Today data science has become the hottest field in the world and I expect that statistics will play an essential role in healthcare data science in the future.

Tell us about your life outside of Vanderbilt. Do you have a significant other? Children? What are your goals for the future?
My wife and I have two lovely sons. I love to play basketball with friends at recreation center and with my kids at backyard. My goal is to keep my family safe and happy in the future.

Finally, what is something about you that most people at Vanderbilt still don't know about you? (Until now, of course!)
My colleagues definitely believe that I am such a kind, mild-mannered person, but you will see a different side to me on the basketball court; I become very focused and assertive.  And I have to admit that I am no good at remembering peoples' names.  So, if you ever meet me down by the court just know that I may not remember your name even though we may have met; please forgive me.