Current Fellows
Pulmonary & Critical Care Fellows
Class of 2025-2028
Shannen Kim, MD
Medical School: UCSF
Residency: UCSF
Bio: Shannen grew up in Chino Hills, California. She went to Harvard for college before coming to the Bay Area for medical school, where she has been ever since. After completing medical school and internal medicine residency at UCSF, she worked as a hospitalist at the San Francisco VA before starting fellowship. She is excited to be joining the Stanford PCCM community and looks forward to exploring her interests in critical care, end-of-life care and communication, and clinical design and innovation. Outside of medicine, she enjoys Tahitian dance, watching reality TV with her cat Sokka, and traveling abroad whenever she can!
Albert Ya-Po Lui, MD
Medical School: New York University
Residency: UCLA
Bio: Albert was born in Taipei, Taiwan and grew up between Taipei and Vancouver, BC. He moved to New York City for college at Columbia University, relocated west to California to pursue a master’s degree at Stanford University, and then returned to New York City for medical school at NYU. During his internal medicine residency training at UCLA, he developed interests in pulmonary hypertension, critical care, and machine learning applications within medicine. Outside of work, Albert enjoys watching horror movies, exploring local coffeeshops, training capoeira, and hiking through national parks.
John Rose, MD
Medical School: University of Virginia
Residency: University of Texas Southwestern
Bio: John was born and raised in Virginia, where he attended college and medical school. He made the trip westward to Dallas for residency at UT Southwestern. Following a chief resident year, he was thrilled to take the next step in his training as a PCCM fellow at Stanford in Sunny California. His academic and clinical interests include implementation science, pulmonary infections, and the care of veterans. Outside the hospital, he enjoys exploring art museums with friends, sampling new ice cream flavors, and the beach!
 Rubin.jpg)
‘Yoni’ Samuel Rubin, PhD, MD
Medical School: Stanford
Residency: Stanford
Bio: Yoni was raised in Seattle, WA and journeyed to California for college where he has meandered since. He is excited to continue training on The Farm as a PCCM fellow and to utilize his experience in immunology for research and clinical applications. Outside the hospital and laboratory, Yoni is an amateur runner as well as a semi-professional farm-to-table chef.
Adrienne Strait, MD
Medical School: UCSF
Residency: UCSF
Bio: Adrienne grew up in Oakland, CA. She attended Williams College in Massachusetts before returning to the Bay Area to complete medical school and residency at UCSF. She spent a year working as a hospitalist in San Francisco before beginning her fellowship at Stanford. Alongside her clinical work, she is passionate about medical education and improving patient safety through quality improvement initiatives. Outside of medicine, she enjoys running, hiking, spending time with friends and family, and baking.
Natalie Stumpf, MD
Medical School: Temple University
Residency: UCSF
Bio: Natalie was born in Oakland, California. She went to college in the Bay Area, moved to the East Coast for medical school at Temple University, then returned to the bay for internal medicine residency at UCSF. Her clinical interests include bronchiectasis and lung transplant. Outside of the hospital, she enjoys reading, knitting, and going on hikes with her dog.
Sangeetha Thevuthasan, MD
Medical School: University of Washington
Residency: Columbia
Bio: Sangeetha grew up in Eastern Washington. She went to college in Atlanta at Georgia Tech and moved back to Washington for medical school at the University of Washington. She ended up in New York City for internal medicine residency at Columbia and is thrilled to be moving back to her favorite coast for fellowship! Her clinical interests include critical care, interventional pulmonology and healthcare technology. Outside of work, she loves to spend time outside whether it’s running, playing basketball, or picnicking in parks.
Jonathan Tiao, MD
Medical School: Columbia
Residency: Columbia
Bio: Jonathan was born in Cincinnati, OH, and went to college at the University of Michigan before moving to the Bay Area for a brief 2 year stint in tech. Afterwards he moved to New York City for both medical school and residency before joining Stanford for fellowship. He is excited to explore his interests in critical care, technology innovation, and entrepreneurship. Outside of the hospital, he enjoys traveling, outdoor activities with his dog, and watching the Bengals/Wolverines.
Pulmonary & Critical Care Fellows
Class of 2024-2027
Tsion Abraham, MD
Medical School: George Washington University
Residency: UCSF
Bio: Tsion was born in Toronto, Ontario. She grew up in Canada until moving to DC to attend medical school at George Washington University. She made the move to the west coast for residency at UCSF and is excited to stay in the Bay Area for fellowship. Her clinical interests include critical care, pulmonary infections and interventional pulmonology. Outside of work, she enjoys running, spin classes and reading sci-fi novels.
Ben Berger, MD
Medical School: University of Utah
Residency: Duke
Bio: Ben grew up in Salt Lake City and went to the University of Utah for college and medical school. He left the mountains for residency at Duke. He is thrilled to return to the west for fellowship. Clinical interests include critical care, point-of-care ultrasound, and COPD. Academic interests include high-value healthcare, advocacy, and implementation science. Outside of work, he enjoys trail running, hiking, breweries, and hanging out with his fiancée and friends.
Chris Calkins, MD
Medical School: Stanford
Residency: Brigham & Women’s
Bio: Chris grew up in New England before making his first journey west for medical school at Stanford. After three years back in Boston for internal medicine residency at Brigham and Women's Hospital, Chris is thrilled to be back at Stanford for his fellowship training. Outside of clinical work, Chris is interested in medical education and quality improvement. When not in the hospital, Chris enjoys running, hiking, and exploring all California has to offer. Chris lives in Menlo Park with his wife, Madeline, and their cat, Piper.
Audrey Chai, MD
Medical School: USC/ Los Angeles General Hospital
Residency: USC/ Los Angeles General Hospital
Bio: Audrey was born and raised in Pasadena, California and is a true Southern California lifer. After finishing college at USC, she went on to complete medical school, internal medicine residency, and a chief residency year at USC/ Los Angeles General Hospital. During the PCCM fellowship interview process, she fell in love with the people and program at Stanford and is excited to come up to the Bay Area for this next chapter. In residency, she developed interests in medical education, rapid response and code blue training and lung cancer disparities. She hopes to work as a pulmonary and critical care clinician-educator after fellowship. Outside of medicine she enjoys spending time outdoors in sunny weather, Peloton-ing, and finding the best bakeries and dessert shops.
Sammy Emont, MD, MPH
Medical School: University of Miami
Residency: Columbia
Bio: Sammy was born in New York City and grew up in South Florida. She went to Yale for college but returned home where she attended University of Miami for medical school. She went back to New York to complete her residency at New York Presbyterian - Columbia and then spent a year working there as a hospitalist before making the big trip out to California to start fellowship at Stanford. Sammy is interested in ILD and lung transplant. Outside the hospital, she loves to run and play/watch tennis, hike with her dog, and visit vineyards.
Erica Mascarenhas, MD
Medical School: Tufts
Residency: Tulane
Bio: Erica was born and raised in Pennsylvania before heading to Boston for college and medical school. She left the East Coast and headed to New Orleans for her Internal Medicine residency at Tulane where she stayed on for an additional chief year during which she got to dance/march in several Mardi Gras parades. In the hospital, she's interested in medical education and health equity. Outside the hospital, she loves to run (with a recent interest in hiking now that she's in the mountains!), bake, listen to music and spend time with friends and family.
Arjun Panda, MD
Medical School: George Washington University
Residency: OHSU
Bio: Arjun was born in Cleveland Ohio, but considers the SF Bay Area his home - which is why after years away, he is thrilled to return for PCCM fellowship at Stanford to build a career helping people with respiratory diseases breathe more comfortably. In addition to his clinical work, he is passionate about clinical informatics, medical education in the ICU, and the history of medicine. When he's not in the hospital you can find him biking around town looking for his next oat-milk latte, or headphones in trying to perfect one of his seasonal Spotify playlists.
Abel Triana, MD, MSc
Medical School: Universidad del Norte, Colombia
Residency: University of Miami
Bio: Abel was born in Cartagena, Colombia, and completed medical training in Barranquilla. He gained research experience at a clinical trial center focused on diabetes and cardiovascular diseases. He then moved to Glasgow, Scotland, to pursue a master's degree in clinical trials and stratified medicine, with a research focus on sepsis and community-acquired pneumonia. During the COVID-19 pandemic, he returned to Colombia to work in the ER and ICU. Prior to joining Stanford, he was in Miami for residency. His professional interests include ILD, sleep medicine, and interventional pulmonology. In my free time, he enjoys traveling with his wife, spending time with friends, and playing soccer.
Pulmonary & Critical Care Fellows
Class of 2023-2026
Mansour Alkhunaizi, MD
Medical School: Royal College of Surgeons in Ireland
Residency: Baylor
Bio: Mansour was born in Denver, Colorado but grew up primarily in Saudi Arabia. He moved to Dublin, Ireland to attend medical school at the Royal College of Surgeons in Ireland (RCSI). He then made his way back to the United States for internal medicine residency at Baylor, where his interest in PCCM grew. He is thrilled to be moving to the west coast to begin his PCCM fellowship at Stanford. His interests are in critical care, point of care ultrasound and medical education. Outside of medicine, Mansour enjoys hiking, spending time in nature, and traveling with family and friends.
Stephanie Chen, MD
Medical School: Univ of Michigan
Residency: UCSF
Bio: Stephanie was born in Lansing, MI and grew up in the Midwest before making the trek to the West Coast for internal medicine residency at UCSF. She is excited to continue staying in the Bay Area as a PCCM fellow at Stanford and to continue exploring her interests include critical care, clinical education/teaching, quality improvement/ICU outcomes. Outside of the hospital, she enjoys baking (joined the trend of sourdough baking during the pandemic), trying out new restaurants, and playing board games with friends.
Alex Heard, MD
Medical School: Univ of South Dakota
Residency: Yale
Bio: Alex was born and raised in Minnesota and attended undergrad and medical school in South Dakota. During residency at Yale, he developed a passion for medical education and created a POCUS and procedural curriculum. Outside of medicine, he enjoys hiking, backpacking, reading, and gardening.
Cyra Kang, MD
Medical School: Catholic University of Korea School of Medicine
Residency: John H. Stroger Hospital of Cook County
Bio: Cyra grew up on Jeju-do, a volcanic island off Korea’s southern coast and first lived in California during high school. She has lived in New Hampshire for undergrad, Korea for medical school, and Chicago for internal medicine residency. She is excited to be living in the Bay Area, which reminds her of the small island where she grew up. Cyra is particularly interested in clinical research on AI-driven prediction models. Outside of medicine, she enjoys playing the violin in chamber music, traveling, hiking, trying out new fitness classes, and going to jazz shows.
Rodrigo Diaz Lankenau, MD
Medical School: Tecnologico de Monterrey
Residency: Univ of Miami
Bio: Rodrigo was born and raised in Monterrey, Mexico where he completed his medical school at Tecnologico de Monterrey. He then chose to continue his training in the US and headed to the University of Miami for residency. During his time there he worked on home oxygen research and completed a medical education pathway. His current academic and research interests include mechanical ventilation, ILD, and interventions to improve medical education. Outside of medicine Rodrigo enjoys hiking, reading, working on his baking skills, and trying new coffee places with his wife.
Tracey Liu, MD
Medical School: Mt Sinai
Residency: UCLA
Bio: Having grown up in Fresno, California and spent her college years in the East Bay, Dr. Liu is thrilled to be returning to the California Bay Area to be training at Stanford. She completed medical school at Mount Sinai and internal medicine residency at UCLA. Having taken care of patients when Covid hit during her intern year, she found a passion in navigating complex goals of care discussions, and honoring patient-centered, goal concordant care. This led her to complete a fellowship in palliative care at NYU. She is excited to integrate her unique training with her passion for critical care medicine, potential interests in ILD and PH. Additional interests include medical education, healthcare disparities, and quality improvement. Outside of medicine she enjoys traveling, trying new foods, learning languages, live music, ice skating, and dancing in her studio.
Ahmed Taha, MD
Medical School: University of Khartoum
Residency: Texas Tech
Bio: Ahmed was born in Sudan. He completed his medical school at the University of Khartoum, Faculty of Medicine, and then moved to the US for his Internal Medicine training. Before embarking at Stanford, Ahmed practiced independently as an Academic Hospitalist in affiliation with Indiana University and also received the honorary FACP designation by the American College of Physicians. Ahmed joined Stanford aspiring to become a leading clinician-educator in the field of pulmonary and critical care medicine with career interests encompassing high-value care in critical care settings and ARDS pharmacotherapy. When not working, Ahmed enjoys spending time with his family, watching/attending stand-up comedy shows, and playing soccer. Ahmed also loves traveling and experiencing new cultures; he has been to 15 countries and counting!
Pulmonary & Critical Care Fellows
T32 Research Fellow
Joseph Rathkey, MD
Medical School: Case Western Reserve University
Residency: Stanford
Bio: Joseph enjoys research (innate immunology and molecular biology), running (generally slowly), reading (articles and books), riding (bikes), and relaxing (with family and friends).
Specialty/Subspecialty Fellows
Class of 2024-2025
Or Bruck, MD
Specialty: Pulmonary Hypertension
Residency: UMass Chan Medical School
PCCM Fellowship: Baylor College of Medicine
Justine Ko, MD
Specialty: Interventional Pulmonology
Residency: University of Southern California + Los Angeles General Medical Center
PCCM Fellowship: University of California, San Francisco - Fresno PCCM Program