Introduction: The possible existence of an ocean beneath the surface of Jupiter’s icy moon Europa has fueled scientific interest in this tiny world. Liquid water is a crucial element in the development of life on Earth, and if present on Europa, increases the likelihood of finding life there as well. Hydrothermal vents on the Europan ocean floor could provide habitat for microbes as well as gen...

During my 2006-2007 VSGC fellowship I modeled the O2 atmosphere of Jupiter’s moon Europa. By assuming that atmospheric O2 can react with species contained in portions of Europa’s surface, my coauthors and I have been able to reproduce the O2 density variations seen by a previously-unexplained HST observation. This work included further refinements to a regolith model that I published previous t...

Tesfaye Bekele 2000. Plant Population Dynamics of Dodonaea angustifolia and Olea europaea ssp. cuspidata in Dry Afromontane Forests of Ethiopia. Acta Universitatis Upsaliensis. Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 559. 47 pp. Uppsala. ISBN 91-554-4781-3. Human disturbance has led to excessive deforestation and to a very limited forest cover...

Previous studies identified the oleABCD genes involved in head-to-head olefinic hydrocarbon biosynthesis. The present study more fully defined the OleABCD protein families within the thiolase, alpha/beta-hydrolase, AMP-dependent ligase/synthase, and short-chain dehydrogenase superfamilies, respectively. Only 0.1 to 1% of each superfamily represents likely Ole proteins. Sequence analysis based o...

The aim of the present study was to confirm that olive oil phenols reduce human platelet aggregability and to verify the hypothesis that cAMP- and cGMP- phosphodiesterases (PDE) could be one of the targets of the biological effect. Four extracts from oils characterized by a high phenol content (HPE), and low phenol levels (LPE) were prepared and analyzed qualitatively and quantitatively by HPLC...

F or most of Earth’s history, life was microscopic and, even today, microorganisms dominate the planet. Hence, we believe that, if life exists beyond Earth, it likely started as microorganisms and may remain at this stage. Much of contemporary astrobiological research focuses on the metabolic potential of microorganisms and their ability to inhabit extreme environments. The search for life beyo...

El Seven Countries Study, que comenzó en 1958, llevó a cabo encuestas en cohortes de varones para determinar sus hábitos alimentarios y les dio seguimiento para determinar su mortalidad por causas especı́ficas. Una de las observaciones realizadas en ese estudio fue que la «dieta mediterránea» (caracterizada por un consumo elevado de verduras, frutas, legumbres, cereales y pescado junto con un co...