Results 41 to 50 of about 10,002 (189)

Deciphering Biosignatures in Planetary Contexts [PDF]

Astrobiology, 2019
Microbial life permeates Earth's critical zone and has likely inhabited nearly all our planet's surface and near subsurface since before the beginning of the sedimentary rock record. Given the vast time that Earth has been teeming with life, do astrobiologists truly understand what geological features untouched by biological processes would look like ...
Chan, Marjorie A., Hinman, Nancy W., Potter-McIntyre, Sally L., Schubert, Keith E., Gillams, Richard J., Awramik, Stanley M., Boston, Penelope J., Bower, Dina M., Des Marais, David J., Farmer, Jack D., Jia, Tony Z., King, Penelope L., Hazen, Robert M., Leveille, Richard J., Papineau, Dominic, Rempfert, Kaitlin R., Sanchez-Roman, Monica, Spear, John R., Southam, Gordon, Stern, Jennifer C., Cleaves, Henderson James   +20 more
openaire   +6 more sources

Exoplanet biosignatures

Astronomy & Geophysics, 2021
Abstract Biosignature science has come a long way in half a century, but its future depends on more interdisciplinary feeback and conceptual innovation.
openaire   +1 more source

The Cell and the Sum of Its Parts: Patterns of Complexity in Biosignatures as Revealed by Deep UV Raman Spectroscopy

Frontiers in Microbiology, 2019
The next NASA-led Mars mission (Mars 2020) will carry a suite of instrumentation dedicated to investigating Martian history and the in situ detection of potential biosignatures. SHERLOC, a deep UV Raman/Fluorescence spectrometer has the ability to detect
Haley M. Sapers, Haley M. Sapers, Haley M. Sapers, Joseph Razzell Hollis, Rohit Bhartia, Luther W. Beegle, Victoria J. Orphan, Jan P. Amend, Jan P. Amend   +8 more
doaj   +1 more source

Trace Element Concentrations Associated with Mid-Paleozoic Microfossils as Biosignatures to Aid in the Search for Life

Life, 2021
Identifying microbial fossils in the rock record is a difficult task because they are often simple in morphology and can be mimicked by non-biological structures.
Andrew Gangidine, Malcolm R. Walter, Jeff R. Havig, Clive Jones, Daniel M. Sturmer, Andrew D. Czaja   +5 more
doaj   +1 more source

Early evolution of purple retinal pigments on Earth and implications for exoplanet biosignatures

, 2018
We propose that retinal-based phototrophy arose early in the evolution of life on Earth, profoundly impacting the development of photosynthesis and creating implications for the search for life beyond our planet.
DasSarma, Shiladitya, Schwieterman, Edward W.   +1 more
core   +1 more source

Fat/Water Separation at 7 T Using a 3D Radial Sequence With Quasi‐Continuous Echo Times

Magnetic Resonance in Medicine, EarlyView.
ABSTRACT Purpose To achieve a reliable fat/water separation (FWS) at 7 T using a new 3D radial sequence and reconstruction workflow with quasi‐continuous TE sampling. Methods A 3D radial density‐adapted sequence with quasi‐continuous TE sampling was developed for a 7 T whole‐body MRI system.
Matthias Rohe, Katharina Tkotz, Armin M. Nagel, Stefan Sommer, Max Brockmüller, Florian Knoll, Michael Uder, Nico Egger, Frederik B. Laun, Tobias Wilferth   +9 more
wiley   +1 more source

Immune non‐response despite effective antiretroviral therapy in people living with HIV: A review of potential mechanisms, biomarkers and therapeutic approaches

HIV Medicine, EarlyView.
Abstract Introduction A proportion of people living with HIV (PLWH) fail to restore their CD4 count or their CD4/CD8 ratio despite effective antiretroviral therapy (ART). PLWH with immune non‐response (INR) are at a higher risk of both AIDS and non‐AIDS events. The underlying mechanisms of INR remain unclear.
Charlotte Silvestre, Antoine Gross, Alain Makinson   +2 more
wiley   +1 more source

The Oxygen Release Instrument: Space Mission Reactive Oxygen Species Measurements for Habitability Characterization, Biosignature Preservation Potential Assessment, and Evaluation of Human Health Hazards

Life, 2019
We describe the design of an instrument, the OxR (for Oxygen Release), for the enzymatically specific and non-enzymatic detection and quantification of the reactive oxidant species (ROS), superoxide radicals (O2•−), and peroxides (O22−,
Christos D. Georgiou, Christopher P. McKay, Richard C. Quinn, Electra Kalaitzopoulou, Polyxeni Papadea, Marianna Skipitari   +5 more
doaj   +1 more source

The Chemical Composition of {\tau} Ceti and Possible Effects on Terrestrial Planets

, 2015
{\tau} Ceti (HD10700), a G8 dwarf with solar mass of 0.78, is a close (3.65 pc) sun-like star where 5 possibly terrestrial planet candidates (minimum masses of 2, 3.1, 3.5, 4.3, and 6.7 Earth masses) have recently been discovered. We report abundances of
Pagano, Michael, Shim, Sang-Heon, Truitt, Amanda, Young, Patrick A.   +3 more
core   +1 more source

Nitrate-Dependent Iron Oxidation: A Potential Mars Metabolism [PDF]

, 2018
This work considers the hypothetical viability of microbial nitrate-dependent Fe2+ oxidation (NDFO) for supporting simple life in the context of the early Mars environment.
Abramov, Amils, Anand, Arevalo, Arnold, Arvidson, Bauermeister, Benz, Bibring, Bridges, Bridges, Bruce, Busigny, Byrne-Bailey, Cabrol, Canfield, Carlson, Carlson, Carr, Chakraborty, Chakraborty, Changela, Charlou, Chassefière, Chastain, Chaudhuri, Chevrier, Cockell, Cockell, Cockell, Comeau, Czaja, Dartnell, Edwards, Edwards, Edwards, Ehlmann, Ehlmann, Ehlmann, Ehrenreich, Emerson, Emerson, Emerson, Etique, Ettwig, Fassett, Filiberto, Fisk, Formisano, Fowler, Fox, Fox, Fox-Powell, Frydenvang, Gauger, Gendrin, Glavin, Grady, Gronstal, Grotzinger, Grotzinger, Hafenbradl, Hecht, Hedrich, Hicks, Hoefen, Hoehler, Hoppert, Hurowitz, Ilbert, Ionescu, Irwin, Jakosky, Jepsen, Johnson, Kappler, Kappler, Kappler, King, Kish, Klueglein, Klueglein, Konhauser, Konn, Kounaves, Kumaraswamy, Lack, Lalonde, Lanza, Laufer, Lopez-Reyes, Lovley, Lovley, Madigan, Mahaffy, Malin, Mangold, Manning, Martin, Martín-Torres, Marzo, McSween, McSween, Michalski, Millero, Ming, Ming, Miot, Miot, Miot, Miot, Miot, Miot, Miot, Miot, Mirvaux, Montoya, Morgan, Morris, Morris, Morris, Muehe, Myers, Nachon, Navarro-González, Nealson, Nie, Nixon, Nixon, Nixon, Oren, Osinski, Palucis, Pantke, Parnell, Pirajno, Popa, Raghoebarsing, Raiswell, Ramirez, Rampe, Rampe, Reimers, Revsbech, Roden, Santelli, Schieber, Schuerger, Schwenzer, Schwenzer, Schädler, Sephton, Sholes, Smith, Smith, Squyres, Squyres, Squyres, Steele, Stern, Stern, Stevens, Straub, Straub, Straub, Strohm, Summers, Summers, Summers, Sutter, Toporski, Tosca, Tosca, Tuff, Vaniman, Visscher, Wacey, Weber, Weber, Weber, Webster, Welhan, Wheat, Williams, Yen, Yen   +185 more
core   +4 more sources