Julia Katz
Julia Katz joined the Warriors Research Institute in June 2024 – July 2025 as a Clinical Research Assistant. She graduated from Southern Methodist University in 2022 with a Bachelor of Arts in Psychology and minors in cognitive science, philosophy, and English literature. She also has a Master of Science in Psychology with a focus in child development from the University of Texas at Dallas.
Nate Kimbrel, PhD
Dr. Nathan Kimbrel is a Clinical Research Psychologist at the Durham VAMC and an Assistant Professor in the Department of Psychiatry and Behavioral Science at Duke University Medical Center. He was previously affiliated with the VISN 17 Center of Excellence for Research on Returning War Veterans and Texas A&M University Health Science Center.
Dr. Kimbrel received his Bachelor's degree in psychology from The Ohio State University in 2000 and his doctorate in clinical psychology from the University of North Carolina at Greensboro in 2009.
His primary areas of interest include the etiology and treatment of PTSD, depression, anxiety, suicide, and deliberate self-harm among returning veterans and emergency responders.
John Klocek, PhD
Dr. Klocek is the Director of Clinical Training of Baylor’s clinical psychology doctoral program as well as the Director of the Baylor Psychology Clinic (which offers clinical services to the citizens of Waco). A Chicago transplant to Texas at the age of 12, Dr. Klocek grew up in the Fort Worth area and began his academic journey at the University of Texas at Austin, where he received his Bachelor of Arts degree in psychology. Dr. Klocek then moved on to complete his graduate education at Saint Louis University.
After serving as an associate professor at the University of Montana, Dr. Klocek joined the VA as a staff psychologist at the Temple VAMC. He later served as the Supervisory Psychologist at the WacoVAMC. Dr. Klocek then joined the VISN 17 Center of Excellence (on the Waco VAMC campus) as the Director of the Treatment Development and Treatment Outcomes Core. During his time working for VA, Dr. Klocek also served as an IRB member and IRB Chair. Working in VA engendered passion for serving veterans . In an effort to continue serving the veteran community, Dr. Klocek entered into collaboration with the WRI, particularly through our recent project, Testing Family Interventions to Motivate Veterans to Seek Treatment, a study focused on helping veterans and their families.
Marc I. Kruse, PhD
Dr. Marc Kruse is the staff psychologist for the Austin Fire Department and Austin-Travis County Emergency Medical Services. He is a licensed clinical psychologist who earned his Ph.D. from the University of Texas at Austin and completed his clinical internship at the Center for Alcohol and Addiction Studies at Brown Medical School and the Providence, Rhode Island Veterans Affairs Medical Center.
He is an Adjunct Assistant Professor (Research) in the Department of Psychiatry and Behavioral Sciences in the College of Medicine at Texas A&M Health Science Center. Prior to joining the City of Austin, Marc was an investigator on multiple federally-funded research projects and directed the data management division of the Central Texas VA and VISN 17 Center of Excellence for Research on Returning War Veterans. In addition to his work with military veterans, Dr. Kruse has been involved in clinical research with firefighters and first-responders from Austin, Boston, Chicago, Dallas, Fairfax, New York, Providence, and Toronto.
The majority of Dr. Kruse’s clinical and research efforts are focused on working with trauma-exposed populations (firefighters, first-responders, military veterans) with particular emphasis on the assessment and treatment of Posttraumatic Stress Disorder (PTSD) and substance use disorders. His clinical practice emphasizes the use of empirically-supported treatments.
Lindsay Lange
Lindsay joined the Warriors Research Institute in July of 2017. She earned a Bachelor of Arts degree in Philosophy from Carleton College in 2003. Her thesis examined cognitive dissonance’s impact on moral reasoning through the lens of Aristotelian virtue ethics. In May of 2016, Lindsay graduated from Texas A&M University – San Antonio with a Master of Arts degree in Counseling and Guidance.
During her studies, she worked in the Neurobehavioral Research Laboratory and Clinic, at the University of Texas Health – San Antonio, researching the efficacy of contingency management interventions for the treatment of adolescent substance use and other externalizing behaviors. She has worked in a partial hospitalization program, counseling individuals with serious mental illness and co-occurring substance use disorder.
Lindsay has also conducted individual and group therapy with bereaved children and their caregivers at the Children’s Bereavement Center of South Texas. Currently, Lindsay is a clinical psychology doctoral student at Baylor University. A native Texan, she enjoys spending time with family, traveling, playing trivia, and searching for the best breakfast taco in Texas.
AJ Franzetti Lawson
AJ joined the WRI team as a practicum student in 2022-2023. He received his B.A. in Psychology from the University of Texas at Austin in 2017, his M.Ed. in Counseling Education from the University of Texas at Austin in 2019, and his Ph.D. in Counseling Psychology from Texas A&M University in. AJ grew up in Austin, TX in a Latino household, and has a passion for working with Latino and underserved communities. Prior to joining WRI, AJ provided counseling services at Texas A&M's Counseling and Psychological Services office as well as working in the Suicide Awareness and Prevention Office. AJ enjoys taking a collaborative approach to therapy, helping clients find their voice and strengths. His hobbies include traveling, being outdoors, and swimming.
Cade Lemmons
Kevin Lentz
Retired Firefighter Kevin Lentz has 20 years of experience as a career firefighter with Garland Fire Department and over 15 additional years as a fire service consultant. Kevin collaborated with Dr. Gulliver on the Peer Support Training and Supervision for Texas Firefighters study.
He has diversified experience in the fields of public safety, research and product development, as well as in-depth field testing and sales. He is a voting member of the NFPA Technical Committee on Electronic Safety Equipment and the Standard on Open-Circuit Self-Contained Breathing Apparatus (SCBA) for Emergency Services. Kevin currently works with Grace Industries, Inc., and he is the sole proprietor of Cool Fire Tools.
Capt. Frank Leto
Capt. Frank Leto is a 30-year veteran of the FDNY and the Deputy Director of its Counseling Service Unit (CSU). His association with the CSU began over 20 years ago as a Crisis Counselor for incidents such as line of duty deaths and mass casualty events. On September 11th, 2001 he responded to the World Trade Center as an officer in charge of a rescue team. Since 9/11, Capt. Leto has developed innovative outreach, counseling and education programs for firefighters and their families who have experienced potentially traumatic events.
In addition to his work as Deputy Director of the CSU and its staff of ninety, he has worked closely with the International Association of Fire Fighters (IAFF) and the National Fallen Firefighters Foundation (NFFF) to develop behavioral health protocols and to aid departments nationwide after major incidents. Captain Leto has also traveled internationally to share his experiences with fire departments in Northern Ireland, the Netherlands and to Okinawa Japan to aid Military Fire Fighters. He has assisted the London Fire Brigade after the transit bombings in 2005, and the Urban Search and Rescue Teams following the devastating earthquake in Haiti in 2010. Through his work with the IAFF and NFFF, he has supported numerous departments including those on the Gulf Coast after Katrina, Charleston, SC and Aurora, Colorado after the theater shooting and more recently Boston following the Marathon Bombing.
Frank was one the first graduates of the West Point - FDNY Terrorism and Counterterrorism Program and also is a Certified Employees Assistance Professional.
Precious Mathis
Precious graduated from Baylor University with a Bachelor of Arts in Psychology. Precious is currently serving as a therapist intern at WRI as she pursues her doctorate degree in clinical psychology. Before joining the WRI team, Precious worked with a variety of patients from different backgrounds using evidence-based approaches. Additionally, Precious is engaged in research that investigates dissemination and implementation of evidence-based substance use treatments to adolescents. Her research work also focuses on increasing access to substance use treatment and mental health support among underserved populations.
For fun, Precious enjoys writing poetry, enjoying nature, cooking, and spending time with her family.
Alton McCallum, MA, LPC
Alton has experience working with PTSD, trauma, anxiety, depression, identity, relationships, fatigue/burnout, and transitional and development issues. Among other therapies, he is trained in Eye Movement Desensitization and Reprocessing Therapy (EMDR) which is an integrative psychotherapy approach that has been extensively researched and proven effective for the treatment of trauma.
As a retired combat veteran, Alton has a special interest in helping service members, veterans, and their family members overcome life's circumstances that affect career, marriage, family and social relationships.
Eric Meyer, PhD
Dr. Meyer is a licensed clinical psychologist, experienced clinician, researcher, trainer and mentor. His clinical expertise is in evidence-based treatments for people living with post-traumatic stress and commonly co-occurring problems such as depression, anxiety, and alcohol and other substance use problems.
Dr. Meyer’s research focuses on 1) identifying modifiable psychological factors that influence mental health challenges and problems with functioning (e.g., relationship and employment-related functioning) over time; and 2) developing and testing interventions that target these factors.
Dr. Meyer has studied predictors of PTSD, other mental health problems, and problems with functional readjustment in war Veterans. He is an expert in Acceptance and Commitment Therapy (ACT), a mindfulness and acceptance-based form of behavior therapy, for co-occurring PTSD and alcohol use problems in Veterans. He has studied mental health challenges, substance use problems and occupational stress in firefighters. He collaborates on studies of risk factors for suicide and self-injury and a study of a novel, intensive form of PTSD treatment. Dr. Meyer has published numerous journal articles and book chapters in the areas of PTSD, other mental health problems, mental health-related disability, traumatic brain injury (TBI), and suicide.
Alex Meyers
Alex Meyers joined the Warriors Research Institute in June 2020 as a practicum student. She is currently a third year Doctoral Program student in Clinical Psychology at Baylor University. Prior to joining WRI, she completed training rotations at the Baylor Psychology Clinic and the Baylor University Counseling Center in Waco, Texas.
Alex’s clinical interests include helping adults navigate the distress they face in everyday life. Alex’s research interests include further understanding anxiety disorders and the relationship of neuroticism and health promotion behaviors.
Alex enjoys spending time with her pets (dog and guinea pigs), working out, and spending time with her friends in her spare time.
Sandra Morissette, PhD
Dr. Morissette received her Ph.D. in clinical psychology from Boston University. She is a professor at The University of Texas at San Antonio. Dr. Morissette’s expertise is in studying co-occurring anxiety and addictive behaviors, having published numerous articles and book chapters in this area.
Her research interests are in studying the impact of traumatic stress and co-occurring mental health disorders on functional recovery processes. She has served as principal investigator (PI) for a series of longitudinal studies that comprise a program of research called, Project SERVE. These studies evaluate modifiable predictors of functional recovery trajectories. Through this research she aims to develop empirically-supported prevention and interventions to improve functional recovery in returning veterans.
Hyeji Na
Hyeji joined the Warriors Research Institute (WRI) team in October 2018. She obtained her Bachelor of Arts degree in Psychology at Emory University and is currently working on her Doctorate in Clinical Psychology from Baylor University.
Prior to joining the WRI, Hyeji completed clinical practica at the Baylor Psychology Clinic, Baylor Scott & White Hillcrest Medical Rehabilitation Center, Bill Logue Juvenile Justice Center and the Baylor University Counseling Center in Waco, TX. She completed her predoctoral internship at the Veterans Affairs North Texas Health Care System in Dallas, TX. Hyeji’s clinical interests include health promotion, disease prevention and positive psychology interventions.
Hyeji’s research experience includes projects evaluating the use of hypnotherapeutic interventions on various medical and psychological concerns, such as tobacco use, hot flashes, sleep problems and enhancing well-being. In her spare time, Hyeji enjoys various forms of exercise, laughing with her friends and family, exploring places near and far and listening to audiobooks on 2x speed (try it!).
Lt. William Ostiguy
Lt. William Ostiguy retired from Boston Fire Department with 40 years of service, many of which were spent developing Behavioral Health systems for the fire department. He has been a standing member of the IAFF’s Behavioral Health Committee for 23 years, and brought Recovery High Schools to the Boston Metropolitan Area.
Lt. Ostiguy has collaborated with Dr. Gulliver since 2001, beginning with the RAPID grant. Since then he has also contributed to the ASD grant, Project PREVENT, Project REACH OUT, Project RESPONDER, and Project RECRUIT.