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Methane Production on Rock and Soil Substrates by Methanogens: Implications for Life on Mars
Bioastronomy 2007: Molecules, Microbes, and Extraterrestrial Life ASP Conference Series, Vol. 420, 2009 K. J. Meech, J. V. Keane, M. J. Mumma, J. L. Siefert, and D. J. Werthimer, eds. Methane Production on Rock and Soil Substrates by Methanogens: Implications for Life on Mars H. A. Kozup and T. A. Kral 1West Virginia University, WV 26505 2Arkansas Center for Space and Planetary Sciences, University of Arkansas, Fayetteville 72701 Abstract. In order to understand the methanogens as models for possible life on Mars, and some of the factors likely to be important in determining their abundance and distribution, we have measured their ability to produce methane on a few types of inorganic rock and soil substrates. Since organic ma- terials have not been detected in measurable quantities at the surface of Mars, there is no reason to believe that they would exist in the subsurface. Samples of three methanogens (Methanosarcina barkeri, Methanobacterium formicicum, and Methanothermobacter wolfeii) were placed on four substrates (sand, gravel, basalt, and a Mars soil simulant, JSC Mars-1) and methane production mea- sured. Glass beads were used as a control substrate. As in earlier experiments with JSC Mars-1 soil simulant, a crushed volcanic tephra, methane was pro- duced by all three methanogens when placed on the substrates, sand and gravel. None produced methane on basalt in these experiments, a mineral common in Martian soil. While these substrates do not represent the full range of materials likely to be present on the surface of Mars, the present results suggest that while some surface materials on Mars may not support this type of organism, others might. -
Radiation Exposure and Mission Strategies for Interplanetary Manned Mission
Radiation Exposure and Mission Strategies for Interplanetary Manned Mission Radiation Hazard and Space Weather Warning System WP 5000 Final Version: 14 December 2004 Compiled by Claire Foullon1, Andrew Holmes-Siedle2, Norma Bock Crosby1, Daniel Heynderickx1 1 Belgian Institute for Space Aeronomy Ringlaan-3-Avenue Circulaire 1180 Brussels, Belgium 2 REM OXFORD Ltd. 64A Acre End St. Eynsham, Oxford OX29 4PD, England INTRODUCTION Radiation protection is a prime issue for space station operations, for extended missions to planets in our solar system (e.g. Mars), or for a return visit to the Moon. The radiation environment encountered by solar system missions mainly consists of the following components: 1. Trapped radiation in the Earth’s Van Allen Belts and in the magnetosphere of Jupiter 2. Galactic Cosmic Ray (GCR) background radiation 3. Solar Energetic Particle Events – Solar Proton Events (SPEs) Along with the continuous GCR background, SPEs constitute the main hazard for interplanetary missions. Up to now, prediction of SPE events is not possible. Future interplanetary manned missions will need to consider solar activity (e.g. solar flares, coronal mass ejections, …) very carefully due to the obvious detrimental effects of radiation on humans. Very high doses during the transit phase of a mission can result in radiation sickness or even death. This is equally true for extended visits to surfaces of other planets (for example to Mars) and moons lacking a strong magnetic field capable of deflecting solar particles. The risk of developing cancer several years after a mission is somewhat more difficult to quantify, but must also be considered in mission planning. -
Histone Variants in Archaea and the Evolution of Combinatorial Chromatin Complexity
Histone variants in archaea and the evolution of combinatorial chromatin complexity Kathryn M. Stevensa,b, Jacob B. Swadlinga,b, Antoine Hochera,b, Corinna Bangc,d, Simonetta Gribaldoe, Ruth A. Schmitzc, and Tobias Warneckea,b,1 aMolecular Systems Group, Quantitative Biology Section, Medical Research Council London Institute of Medical Sciences, London W12 0NN, United Kingdom; bInstitute of Clinical Sciences, Faculty of Medicine, Imperial College London, London W12 0NN, United Kingdom; cInstitute for General Microbiology, University of Kiel, 24118 Kiel, Germany; dInstitute of Clinical Molecular Biology, University of Kiel, 24105 Kiel, Germany; and eDepartment of Microbiology, Unit “Evolutionary Biology of the Microbial Cell,” Institut Pasteur, 75015 Paris, France Edited by W. Ford Doolittle, Dalhousie University, Halifax, NS, Canada, and approved October 28, 2020 (received for review April 14, 2020) Nucleosomes in eukaryotes act as platforms for the dynamic inte- additional histone dimers can be taggedontothistetramertoyield gration of epigenetic information. Posttranslational modifications oligomers of increasing length that wrap correspondingly more DNA are reversibly added or removed and core histones exchanged for (3, 6–9). Almost all archaeal histones lack tails and PTMs have yet to paralogous variants, in concert with changing demands on tran- be reported. Many archaea do, however, encode multiple histone scription and genome accessibility. Histones are also common in paralogs (8, 10) that can flexibly homo- and heterodimerize in -
Field Measurements of Terrestrial and Martian Dust Devils Journal Item
Open Research Online The Open University’s repository of research publications and other research outputs Field Measurements of Terrestrial and Martian Dust Devils Journal Item How to cite: Murphy, Jim; Steakley, Kathryn; Balme, Matt; Deprez, Gregoire; Esposito, Francesca; Kahanpää, Henrik; Lemmon, Mark; Lorenz, Ralph; Murdoch, Naomi; Neakrase, Lynn; Patel, Manish and Whelley, Patrick (2016). Field Measurements of Terrestrial and Martian Dust Devils. Space Science Reviews, 203(1) pp. 39–87. For guidance on citations see FAQs. c 2016 Springer https://creativecommons.org/licenses/by-nc-nd/4.0/ Version: Accepted Manuscript Link(s) to article on publisher’s website: http://dx.doi.org/doi:10.1007/s11214-016-0283-y Copyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyright owners. For more information on Open Research Online’s data policy on reuse of materials please consult the policies page. oro.open.ac.uk 1 Field Measurements of Terrestrial and Martian Dust Devils 2 Jim Murphy1, Kathryn Steakley1, Matt Balme2, Gregoire Deprez3, Francesca 3 Esposito4, Henrik Kahapää5, Mark Lemmon6, Ralph Lorenz7, Naomi Murdoch8, Lynn 4 Neakrase1, Manish Patel2, Patrick Whelley9 5 1-New Mexico State University, Las Cruces NM, USA 2 - Open University, Milton Keynes UK 6 3 - Laboratoire Atmosphères, Guyancourt, France 4 - INAF - Osservatorio Astronomico di 7 Capodimonte, Naples, Italy 5 - Finnish Meteorological Institute, Helsinki, Finland 6 - Texas 8 A&M University, College Station TX, USA 7 -Johns Hopkins University Applied Physics Lab, 9 Laurel MD USA 8 - ISAE-SUPAERO, Toulouse University, France 9 - NASA Goddard 10 Space Flight Center, Greenbelt MD, USA 11 submitted to SSR 10 May, 2016 12 Revised manuscript 08 August 2016 13 ABSTRACT 14 Surface-based measurements of terrestrial and martian dust devils/convective vortices 15 provided from mobile and stationary platforms are discussed. -
18Th EANA Conference European Astrobiology Network Association
18th EANA Conference European Astrobiology Network Association Abstract book 24-28 September 2018 Freie Universität Berlin, Germany Sponsors: Detectability of biosignatures in martian sedimentary systems A. H. Stevens1, A. McDonald2, and C. S. Cockell1 (1) UK Centre for Astrobiology, University of Edinburgh, UK ([email protected]) (2) Bioimaging Facility, School of Engineering, University of Edinburgh, UK Presentation: Tuesday 12:45-13:00 Session: Traces of life, biosignatures, life detection Abstract: Some of the most promising potential sampling sites for astrobiology are the numerous sedimentary areas on Mars such as those explored by MSL. As sedimentary systems have a high relative likelihood to have been habitable in the past and are known on Earth to preserve biosignatures well, the remains of martian sedimentary systems are an attractive target for exploration, for example by sample return caching rovers [1]. To learn how best to look for evidence of life in these environments, we must carefully understand their context. While recent measurements have raised the upper limit for organic carbon measured in martian sediments [2], our exploration to date shows no evidence for a terrestrial-like biosphere on Mars. We used an analogue of a martian mudstone (Y-Mars[3]) to investigate how best to look for biosignatures in martian sedimentary environments. The mudstone was inoculated with a relevant microbial community and cultured over several months under martian conditions to select for the most Mars-relevant microbes. We sequenced the microbial community over a number of transfers to try and understand what types microbes might be expected to exist in these environments and assess whether they might leave behind any specific biosignatures. -
Methanobacterium Paludis Sp. Nov. and a Novel Strain of Methanobacterium Lacus Isolated from Northern Peatlands
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by The University of North Carolina at Greensboro Archived version from NCDOCKS Institutional Repository http://libres.uncg.edu/ir/asu/ Methanobacterium Paludis Sp. Nov. And A Novel Strain Of Methanobacterium Lacus Isolated From Northern Peatlands By: Suzanna L. Brauer, Hinsby Cadillo-Quiroz, Noah Goodson, Joseph B. Yavitt & Stephen H. Zinder Abstract Two mesophilic, hydrogenotrophic methanogens, designated strains SWAN1T and AL-21, were isolated from two contrasting peatlands: a near circumneutral temperate minerotrophic fen in New York State, USA, and an acidic boreal poor fen site in Alaska, USA, respectively. Cells of the two strains were rod-shaped, non- motile, stained Gram-negative and resisted lysis with 0.1 % SDS. Cell size was 0.6 1.5–2.8 mm for strain SWAN1T and 0.45–0.85 1.5–35 mm for strain AL-21. The strains used H2/CO2 but not formate or other substrates for methanogenesis, grew optimally around 32–37 6C, and their growth spanned through a slightly low to neutral pH range (4.7–7.1). Strain AL-21 grew optimally closer to neutrality at pH 6.2, whereas strain SWAN1T showed a lower optimal pH at 5.4–5.7. The two strains were sensitive to NaCl with a maximal tolerance at 160 mM for strain SWAN1T and 50 mM for strain AL-21. Na2S was toxic at very low concentrations (0.01–0.8 mM), resulting in growth inhibition above these values. The DNA G+C content of the genomes was 35.7 mol% for strain SWAN1T and 35.8 mol% for strain AL-21. -
METHANOGENS AS MODELS for LIFE on MARS. R. L. Mickol1, W. H. Waddell2, and T
Eighth International Conference on Mars (2014) 1005.pdf METHANOGENS AS MODELS FOR LIFE ON MARS. R. L. Mickol1, W. H. Waddell2, and T. A. Kral1,3, 1Arkansas Center for Space and Planetary Sciences, 202 Old Museum Building, University of Arkansas, Fayetteville, Arkansas, 72701, USA, [[email protected]], 2Dept. of Health, Human Performance, and Recreation, HPER 308, University of Arkansas, Fayetteville, Arkansas, 72701, USA, 3Dept. of Biological Sciences, SCEN 632, University of Arkansas, Fayetteville, Arkansas, 72701, USA. Introduction: The discovery of methane in the Sciences, University of Arkansas, Fayetteville, Arkan- martian atmosphere [1-4] has fueled the study of meth- sas. All four methanogen species were tested in these anogens as ideal candidates for life on Mars. Methano- experiments. Methanogens were grown in their respec- gens are chemoautotrophs from the domain Archaea. tive anaerobic growth media and placed into the cham- These microorganisms utilize hydrogen as an energy ber with a palladium catalyst box to remove residual source and carbon dioxide as a carbon source to pro- oxygen. The chamber was evacuated to a pre- duce methane. Methanogens can be considered ideal determined pressure and filled with 80:20 H2:CO2 gas. candidates for life on Mars because they are anaerobic, This procedure was repeated three times to ensure re- they do not require organic nutrients and are non- moval of the atmosphere. The chamber was then main- photosynthetic, indicating they could exist in sub- tained at the desired pressure (133-143 mbar, 67-72 surface environments. mbar, 33-38 mbar, 6-10 mbar, 7-20 mbar) for the dura- Our lab has studied methanogens as models for life tion of the experiments. -
6 FOTON RETRIEVABLE CAPSULES This Section Is Aimed at Providing New and Experienced Users with Basic Utilisation Information Regarding Foton Retrievable Capsules
6 FOTON RETRIEVABLE CAPSULES This section is aimed at providing new and experienced users with basic utilisation information regarding Foton retrievable capsules. It begins with an introduction to the Foton capsule. 6.1 Introduction to Foton Capsules 6.1.1 What Are Foton Capsules? Foton capsules (Figure 6-1 and Figure 6-2) are unmanned, retrievable capsules, derived from the design of the 1960’s Soviet Vostok manned spacecraft and the Zenit military reconnaissance satellite. These capsules are very similar to the Bion and Resurs-F satellites introduced by the Soviets in the 1970’s, for biological research and Earth natural resources investigation, respectively. The first Foton capsule was launched in 1985 as Cosmos 1645 and only with the fourth launch in 1988 was the spacecraft officially designated Foton (Foton-4). These capsules are launched into near-circular, low-earth orbits by a Soyuz-U rocket, providing researchers with gravity levels less than 10 -5 g, for missions lasting approximately 2 weeks. The earlier Foton missions were conceived primarily for materials science research, but later missions also began to include experiments in the fields of fluid physics, biology and radiation dosimetry. ESA’s participation in the Foton programme began in 1991 with a protein crystallisation experiment on-board Foton-7, followed by a further 35 experiments up to and including the Foton- 12 mission in 1999. In 2002, ESA provided a large number of experiments for the Foton-M1 mission (the first flight of an upgraded version of the Foton spacecraft). This mission ended in disaster when the Soyuz launcher rocket exploded shortly after lift-off due to a malfunction in one of its engines. -
The Space Exposure Platforms BIOPAN and EXPOSE to Study
The space exposure platforms BIOPAN and EXPOSE to study living organisms in space Wolfgang Schulte (1), Pietro Baglioni (2), René Demets (2), Ralf von Heise-Rotenburg (1), Petra Rettberg (3) (1) Kayser-Threde GmbH, Wolfratshauser Str. 48, 81379 Munich, Germany, [email protected], Phone: +49-89-72495-225, Fax: +49-89-72495-215; [email protected], Phone: +49-89-72495-341, Fax: +49-89-72495-215 (2) European Space Agency ESA/ESTEC, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands, [email protected], Phone + 31-71-565-3856, Fax +31-71-565-3141; [email protected], Phone +31-71-565-5081, Fax +31-71-565-3141 (3) German Aerospace Center (DLR e.V.), Institute of Aerospace Medicine, Linder Höhe, 51147 Köln, Germany, [email protected], Phone +49-2203-601-4637, Fax +49-2203-61970 BIOPAN and EXPOSE are two European space exposure platforms, developed for the European Space Agency by Kayser-Threde GmbH, Munich/Germany to offer flight opportunities to the science community of exo/astrobiology research in low earth orbit. Both platforms are conceived for the research on the behaviour of living organisms in the environment of space and on simulated conditions of other planets (Mars). The conditions for a possible transfer of life between planets can be studied. Both facilities can also be used for materials and components validation and as test bed for advanced technologies envisaged for future exploration missions (radio-protection, miniaturized devices, electronic components). Since 1992 BIOPAN has flown five times aboard the Russian FOTON re-entry cap- sule. -
IRPA13 Final Program
IRPA13 v v Final Programme v DOCHART CARRON To Clyde Auditorium, Forth and Gala Rooms and Hotel HALL 4 LOMOND BOISDALE ALSH 13 - 18 May 2012 CLYDE AUDITORIUMCLYDE AUDITORIUM Magnox Fuel Pond Alternative ILW Treatment Bradwell turbine hall MagnoxDecommissioning Fuel Pond Alternative& Disposition ILW Treatment demolitionBradwell turbine hall FORTH ROOM Decommissioning & Disposition demolition (GROUND FLOOR) GALA ROOM (FIRST FLOOR) ProvidingProviding integrated integrated services andand solutions to the global nuclear industry TOILETS (WC’s) M-MALE F-FEMALE TOILETS CLOAKROOM solutions to the global nuclear industry TOILETS FOR DISABLED SHOP EnergySolutions is an international nuclear services company MEDICAL CENTRE BABYCARE ROOMS Magnox Fuel Pond Alternative ILW Treatment Bradwell turbine hall INFORMATION & BUSINESS CENTRE CATERING DecommissioningEnergywith operationsSolutions aroundis& anDisposition international the world, Energy nuclearSolutions’ servicesdemolition work company BOX OFFICE LIFT withspans operations the nuclear around life cycle the world, from operating EnergySolutions’ nuclear power work BANK RECEPTION spansstations the throughnuclear late-life life cycle management from operating and on nuclear to defueling, power stationsdecommissioning, through late-life waste management processing and and packaging, on to defueling, and Providingdecommissioning,complete integrated site restoration. waste processing services and packaging, and and complete site restoration. Registration, Exhibition, solutionsIn the UK,to wethe manage, global on behalf nuclear of the Nuclear industry Hall 4 SECC, Glasgow Posters and Catering Decommissioning Authority, 22 Magnox reactors across 10 In sites,the UK, over we seeing manage, the safe on behalfdelivery of of the continued Nuclear operations. Opening Ceremony, Plenary EnergyDecommissioningSolutions is an Authorit internationaly, 22 Magnox nuclear reactors services across 10 company Clyde Auditorium sites,For further over information seeing contact: the safe delivery of continued operations. -
Field Measurements of Terrestrial and Martian Dust Devils
Open Archive TOULOUSE Archive Ouverte ( OATAO ) OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. This is an author-deposited version published in: http://oatao.univ-toulous e.fr/ Eprints ID: 17289 To cite this version : Murphy, Jim and Steakley, Kathryn and Balme, Matt and Deprez, Gregoire and Esposito, Francesca and Kahanpaa, Henrik and Lemmon, Mark and Lorenz, Ralph and Murdoch, Naomi and Neakrase, Lynn and Patel, Manish and Whelley, Patrick Field Measurements of Terrestrial and Martian Dust Devils. (2016) Space Science Reviews, vol. 203 (n° 1). pp. 39-87. ISSN 0038-6308 Official URL: http://dx.doi.org/10.1007/s11214-016-0283-y Any correspondence concerning this service should be sent to the repository administrator: [email protected] Field Measurements of Terrestrial and Martian Dust Devils Jim Murphy1 · Kathryn Steakley1 · Matt Balme2 · Gregoire Deprez3 · Francesca Esposito4 · Henrik Kahanpää5,6 · Mark Lemmon7 · Ralph Lorenz8 · Naomi Murdoch9 · Lynn Neakrase1 · Manish Patel2 · Patrick Whelley10 Abstract Surface-based measurements of terrestrial and martian dust devils/convective vor- tices provided from mobile and stationary platforms are discussed. Imaging of terrestrial dust devils has quantified their rotational and vertical wind speeds, translation speeds, di- mensions, dust load, and frequency of occurrence. Imaging of martian dust devils has pro- vided translation speeds and constraints on dimensions, but only limited constraints on ver- tical motion within a vortex. The longer mission durations on Mars afforded by long op- erating robotic landers and rovers have provided statistical quantification of vortex occur- rence (time-of-sol, and recently seasonal) that has until recently not been a primary outcome of more temporally limited terrestrial dust devil measurement campaigns. -
Large Carbon Isotope Variability During Methanogenesis Under Alkaline Conditions Hannah M
Large carbon isotope variability during methanogenesis under alkaline conditions Hannah M. Millera Nabil Chaudhrya Mark E. Conradb Markus Billb Sebastian H. Kopfa Alexis S. Templetona Abstract 13 High carbon isotope values (δ CCH4 > −40‰) have widely been used as evidence that methane in alkaline rock-hosted fluids was formed abiotically, particularly in serpentinizing systems. However, isotope fractionation during microbial methanogenesis is relatively understudied at high pH. We isolated a hydrogenotrophic Methanobacterium sp. from hyperalkaline subsurface fluids in the Samail ophiolite to assess how carbon and hydrogen isotope values of CH4 varied depending upon pH and carbonate mineral source (NaHCO3 or CaCO3). The hydrogen isotope fractionation αH20/CH4 (1.46–1.66) did not vary across pH. In contrast, the expressed carbon isotope fractionation, αCO2/CH4, ranged from 1.028 to 1.089. Carbon isotope fractionation increased with pH, reaching a maximum 13C depletion of −85‰. However, the 13C depletion significantly diminished at pH ≥ 9 for 13 CaCO3-amended experiments, generating δ CCH4 as high as −28‰. To 13 evaluate the large variability in δ CCH4, we developed a steady-state model to assess how the rates of carbonate dissolution, cellular uptake of CO2 and irreversible CH4 production can affect the net isotope fractionation during 13 methanogenesis. Methanobacterium sp. can produce highly depleted δ CCH4 in simulated alkaline serpentinizing fluids when dissolved inorganic carbon levels are high and methanogenesis rates are slow. However, small carbon isotope fractionation occurs when rates of carbonate dissolution are slower 13 than cellular uptake, leading to relatively high δ CCH4 values (>∼−35‰) that are traditionally interpreted to be purely “abiotic”.