Stanford University
Showing 751-760 of 2,068 Results
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Alex Hedgpeth
Postdoctoral Scholar, Earth System Science
BioAlexandra Hedgpeth is a biogeochemist whose research explores how soil carbon cycling in peatlands responds to environmental change. Her work focuses on understanding the mechanisms that regulate carbon storage and greenhouse gas production in both tropical and boreal wetlands, with a particular emphasis on the vulnerability of deep, ancient carbon to modern surface inputs and hydrologic shifts.
Through her Ph.D. research at the University of California, Los Angeles, Alex has developed and applied novel isotopic and geochemical approaches—including implementing radiocarbon dating, stable isotope analyses, and high-resolution molecular characterization—to trace the sources and fates of carbon in peat soils. Her fieldwork spans a range of ecosystems, from ombrotrophic bogs in the Arctic to saturated tropical peat domes in Central America. This comparative framework allows her to identify unifying controls on carbon preservation and loss across climate zones.
Alex's research integrates field measurements, laboratory experiments, and synthesis of global datasets. She is a key contributor to multi-institutional efforts to model peatland carbon cycling under climate change scenarios, including DOE- and NSF-supported initiatives. Her work helps clarify the role of peatlands as both long-term carbon sinks and potential sources of atmospheric CO₂ and CH₄ under future disturbance.
In addition to her scientific contributions, Alex is committed to collaborative, interdisciplinary research and has worked closely with partners at national laboratories, the Smithsonian Tropical Research Institute, and international data synthesis networks. She is especially interested in questions with high uncertainty and high relevance to climate feedbacks—such as thresholds in biogeochemical function and the persistence of deep soil carbon under hydrologic change. -
Britt Hedman
Professor of Photon Science
BioBritt Hedman’s research program is focused on the development and applications of x-ray absorption and emission spectroscopies using synchrotron radiation, with a scientific emphasis primarily on study of the electronic and structural aspects of metal ion active sites in bioinorganic and biological systems. A common theme is to investigate how structure at molecular and macromolecular levels relates to function.
A major long-term focus has been the active site of the enzyme nitrogenase, and the various nitrogenase metal clusters, including elucidating the electronic and geometric structure of those that are formed and changed along their biosynthetic pathways. Other systems of systematic studies include iron-sulfur cluster containing enzymes, blue and multi-copper proteins, heme-copper oxidases, and iron-containing oxidases. Methods developments include x-ray absorption spectroscopy (edge and extended fine structure - or EXAFS), including the application of multiple-scattering analysis in EXAFS studies of metal clusters relevant to bioinorganic systems, the development of methodology for polarized single crystal x-ray absorption spectroscopy, and methodology and instrumentation development for soft- through hard-energy XAS.
Britt Hedman received her B.S and B.A. in Chemistry, M.Sc. in Inorganic Chemistry, and Ph.D. in Chemistry from the University of Umeå, Sweden. She was Assistant Professor (equivalent) in Inorganic Chemistry at the University of Umeå before coming to Stanford, initially as Senior Academic Scientific Staff, followed by appointed as Professor (Research) in 2002, and Professor of Photon Science in 2007. -
Johannes Bodo Heekerens
Affiliate, Psychology
BioI am a clinical psychologist studying the nature of human well-being and ways to improve it. My current research focus is on dissociation and affect regulation. I am currently a visiting scholar at Stanford University’s Psychophysiology Lab, supported by a fellowship from the Deutsche Forschungsgemeinschaft (DFG). Additionally, I am a research fellow at Charité – Universitätsmedizin Berlin. I earned my Ph.D. in psychology from Freie Universität Berlin and am also a German board-certified cognitive-behavioral psychotherapist, having completed my training at the Zentrum für Psychotherapie der Humboldt-Universität zu Berlin.
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Gregory M. Heestand, MD
Clinical Associate Professor, Medicine - Oncology
BioDr. Heestand is a board-certified medical oncologist with a focus on gastrointestinal cancers, primarily hepatocellular carcinoma, cholangiocarcinoma, and gallbladder cancer. He serves as the medical oncology champion of the Stanford Hepatobiliary Tumor Board, as well as the principal investigator of multiple clinical trials. He collaborates with campus laboratories to help develop new biomarker and treatment technologies. He is the former director of the Stanford Oncology Fellowship Program.
Dr. Heestand and his team take great pride in helping patients and their families face gastrointestinal cancer.
Outside of the clinic, Dr. Heestand enjoys playing the piano, teaching his kids about music, cooking for friends and family, and surfing the internet for interesting things to read.
