Featured grants
- Christopher, Russian J (Principal), Percent Contribution: %25, Sam Gregory (Co-Principal), Percent Contribution: %25, Waugh, Jonathan (Supporting), Percent Contribution: %25, Dunlevy, Crystal, Percent Contribution: %25. Critical Thinking and Clinical Judgement Skills in Recent Graduates of Associate Degree and Baccalaureate Degree Programs, American Association for Respiratory Care, Private / Foundation / Corporate, $48950. (Funded: October 1, 2018 - September 30, 2019). Grant.
- Marshall, Sam Gregory. Texas State Athlete Sleep Wellness Program — Development Grant, $10000.00. (Funded: 2007). Grant.
- Marshall, Sam Gregory. Texas State Athlete Sleep Wellness Program — Development Grant, $13500.00. (Funded: 2006). Grant.
- Marshall, Sam Gregory. Texas State Football Sleep Wellness Program, Respironics Phillips Corp., $23772.50. (Funded: 2006). Grant.
- Marshall, Sam Gregory. Respironics Phillips Corp., Texas State Football Sleep Wellness Program, $9985.00. (Funded: 2006). Grant.

Featured scholarly/creative works
- Marshall, S. G. (2025). Regulation of Breathing. In Egan’s Fundamentals of Respiratory Care (13th ed). St. Louis, MO, USA: Elsevier.
- Marshall, S. G. (n.d.). Physiology of Sleep Disordered Breathing. In Respiratory Care Anatomy and Physiology: Foundations for Clinical Practice (pp. 247–266). St. Louis, MO, USA: Elsevier.
- Johnson, M. L., Marshall, S. G., Kelemen, W. L., & Westerberg, C. E. (2019). The effects of a single night of continuous positive airway pressure on memory in patients with obstructive sleep apnea. Sleep, 42(A33).
- Marshall, S. G. (2017). Physiology of Sleep Disordered Breathing. In Respiratory Care Anatomy and Physiology. Philadelphia, PA, USA: Mosby/Elsevier.
- Marshall, S. G., Henry, R. H., & Russian, C. J. (2016). Right versus left prong nasal cannula flow rate delivery and the effects of nasal cycling on inspired F102 in an adult anatomic model. Journal of Respiratory Care, 61, 397–404. https://doi.org/10.4187/respcare.04169
Featured awards
- Award / Honor Nominee: Service Excellence Award, College of Health Professions. 2016
- Award / Honor Recipient: Dedication of Service Award, Texas Society for Sleep Professionals. October 2015
- Award / Honor Recipient: Texas State University Service Award for "Thirty-five Years of Service". September 1, 2015
- Award / Honor Nominee: Teaching Excellence Award, College of Health Professions. 2013
- Award / Honor Recipient: Alpha Chi National Honor Society Favorite Professor Award, Alfred H. Nolle Chapter, Texas State University. 2011

Featured service activities
Texas Medical Board -- Texas Board for Respiratory Care
- Other
Department of Physical Therapy
Round Rock Chamber of Commerce Annual Awards Banquet
- Vice President
Coalition for Baccalaureate & Graduate Respiratory Therapy Education, Executive Board of Directors
- Member
Virginia Academy of Sleep Medicine
- Other
Coalition for Baccalaureate & Graudate Respiratory Therapy Education