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Sökning: L773:1473 5504 OR L773:1475 3006

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1.
  • Boettcher, Thomas, et al. (författare)
  • The HADES mission concept : astrobiological survey of Jupiter's icy moon Europa
  • 2009
  • Ingår i: International Journal of Astrobiology. - 1473-5504 .- 1475-3006. ; 8:4, s. 321-329
  • Tidskriftsartikel (refereegranskat)abstract
    • The HADES Europa mission concept aims to provide a framework for an astrobiological in-depth investigation of the Jupiter moon Europa, relying on existing technologies and feasibility. This mission study proposes a system consisting of an orbiter, lander and cryobot as a platform for detailed exploration of Europa. While the orbiter will investigate the presence of a liquid ocean and characterize Europa's internal structure, the lander will survey local dynamics of the ice layer and the surface environment. The lander releases a cryobot, that melts into the ice, will sample the pristine subsurface and is expected to provide data on organic and gaseous content and putative bio-signatures. In summary, we present the scientific objectives for an astrobiological investigation of Europa, resulting in a mission concept with a detailed evaluation of scientific instrumentation, mission sequences, basic design of the spacecraft, technology needs and cost estimations.
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2.
  • Chon-Torres, Octavio Alfonso, et al. (författare)
  • Astrobiocentrism : Reflections on challenges in the transition to a vision of life and humanity in space
  • 2024
  • Ingår i: International Journal of Astrobiology. - : Cambridge University Press. - 1473-5504 .- 1475-3006. ; 23:e6, s. 1-17
  • Tidskriftsartikel (refereegranskat)abstract
    • Astrobiocentrism is a vision that places us in a scenario of confirmation of life in the universe, either as a second genesis or as an expansion of humanity in space. It manages to raise consistent arguments in relation to questions such as what would happen to knowledge if life were confirmed in the universe, how would this change the way we understand our place in the cosmos? Astrobiocentrism raises a series of reflections in the context of confirmed discovery, and it develops concepts that work directly with what would happen after irrefutable evidence has been obtained that we are not alone in space. Unlike biocentrism or ecocentrism, the astrobiocentric view is not limited to the Earth-centric perspective, and for it incorporates a multi-, inter- and transdisciplinary understanding. Therefore, the aim of this paper is to make a reflection on the astrobiocentric issues related to the challenges and problems of the discovery of life in the universe and the expansion of mankind into space. Here we explore some aspects of the transition from biogeocentrism to astrobiocentrism, astrobiosemiotics, homo mensura, moral community, planetary sustainability and astrotheology.
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3.
  • Cockell, Charles S., et al. (författare)
  • Subsurface scientific exploration of extraterrestrial environments (MINAR 5) : analogue science, technology and education in the Boulby Mine, UK
  • 2019
  • Ingår i: International Journal of Astrobiology. - : Cambridges Institutes Press. - 1473-5504 .- 1475-3006. ; 18:2, s. 157-182
  • Tidskriftsartikel (refereegranskat)abstract
    • The deep subsurface of other planetary bodies is of special interest for robotic and human exploration. The subsurface provides access to planetary interior processes, thus yielding insights into planetary formation and evolution. On Mars, the subsurface might harbour the most habitable conditions. In the context of human exploration, the subsurface can provide refugia for habitation from extreme surface conditions. We describe the fifth Mine Analogue Research (MINAR 5) programme at 1 km depth in the Boulby Mine, UK in collaboration with Spaceward Bound NASA and the Kalam Centre, India, to test instruments and methods for the robotic and human exploration of deep environments on the Moon and Mars. The geological context in Permian evaporites provides an analogue to evaporitic materials on other planetary bodies such as Mars. A wide range of sample acquisition instruments (NASA drills, Small Planetary Impulse Tool (SPLIT) robotic hammer, universal sampling bags), analytical instruments (Raman spectroscopy, Close-Up Imager, Minion DNA sequencing technology, methane stable isotope analysis, biomolecule and metabolic life detection instruments) and environmental monitoring equipment (passive air particle sampler, particle detectors and environmental monitoring equipment) was deployed in an integrated campaign. Investigations included studying the geochemical signatures of chloride and sulphate evaporitic minerals, testing methods for life detection and planetary protection around human-tended operations, and investigations on the radiation environment of the deep subsurface. The MINAR analogue activity occurs in an active mine, showing how the development of space exploration technology can be used to contribute to addressing immediate Earth-based challenges. During the campaign, in collaboration with European Space Agency (ESA), MINAR was used for astronaut familiarization with future exploration tools and techniques. The campaign was used to develop primary and secondary school and primary to secondary transition curriculum materials on-site during the campaign which was focused on a classroom extra vehicular activity simulation.
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4.
  • de Souza, Claudio M. D., et al. (författare)
  • Interaction of forsterite-91 with distilled water and artificial seawater : a prebiotic chemistry experiment
  • 2013
  • Ingår i: International Journal of Astrobiology. - 1473-5504 .- 1475-3006. ; 12:2, s. 135-143
  • Tidskriftsartikel (refereegranskat)abstract
    • In the present work, the interactions between forsterite-91 with distilled water and forsterite-91 with artificial seawater were studied at two pHs (2.0 and 8.0) using different techniques. A large increase in pH was observed for samples incubated at an initially acidic pH (2.0) due to the dissolution of forsterite-91 in distilled water and artificial seawater. Thus, in acidic hydrothermal vents, an increase in the amount of hydrocarbons and magnetite should be expected due to the release of Fe(II). The pH(PZC) decreased and the pH(IEP) increased when forsterite-91 was treated with distilled water and artificial seawater. The ions from the artificial seawater had an effect on zeta potential. Scanning electron microscopy (SEM) images and X-ray diffractograms showed halite in the samples of forsterite-91 mixed with artificial seawater. The presence of halite or adsorption of ions on the surface of forsterite-91 could affect the synthesis of magnetite and hydrocarbons in hydrothermal vents, due to a decrease in the dissolution rates of forsterite-91. The dissolution of forsterite-91 yields low concentrations of Fe(III) and Mn(II) as detected by electron paramagnetic resonance (EPR) spectroscopy. Microanalysis of forsterite-91 showed a higher amount of Mn, with an oxidation that was likely not + II, as Mn in supernatant solutions was only detected by EPR spectroscopy after mixing with artificial seawater at pH 2.0. As Fe(III) and Mn(II) are catalyst constituents of magnetite and manganese oxide, respectively, their presence is important for synthesis in hydrothermal vents. Etch pits were observed only in the forsterite-91 sample mixed with distilled water at pH 8.0. Na, Cl, S, Ca and K were detected in the samples mixed with artificial seawater by SEM-EDS. Si, Mg, Fe and Al were detected in almost all supernatant samples due to forsterite-91 dissolution. Cr was not dissolved in the experiments, thus Cr in the mineral could serve as an effective catalyst for Fischer Tropsch Types (FTT) reactions in hydrothermal vent systems. X-ray diffractograms of the original forsterite-91 also showed peaks arising from zeolites and clinochlore. After the samples were treated with artificial seawater, X-ray diffractograms showed the dissolution of zeolite. Experiments should be performed in the natural environment to verify the potential for zeolites to act as a catalyst in hydrothermal vents.
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5.
  • Goetz, W., et al. (författare)
  • MOMA : The challenge to search for organics and biosignatures on Mars
  • 2016
  • Ingår i: International Journal of Astrobiology. - : Cambridge University Press. - 1473-5504 .- 1475-3006. ; 15:3, s. 239-250
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper describes strategies to search for, detect, and identify organic material on the surface and subsurface of Mars. The strategies described include those applied by landed missions in the past and those that will be applied in the future. The value and role of ESA's ExoMars rover and of her key science instrument Mars Organic Molecule Analyzer (MOMA) are critically assessed.
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6.
  • Larsson, Mats (författare)
  • H-3(+) : the initiator of interstellar chemistry
  • 2008
  • Ingår i: International Journal of Astrobiology. - 1473-5504 .- 1475-3006. ; 7:04-mar, s. 237-241
  • Tidskriftsartikel (refereegranskat)abstract
    • Second only to H-2, protonated molecular hydrogen, H-3(+), is the most abundantly produced interstellar molecule. Owing to its high reactivity and acidity, it plays the pivotal role in initiating interstellar chemical reactions, something which also reduces its steady-state concentration. Interstellar H-3(+) is not only destroyed in chemical reactions but also in dissociative recombination with electrons. The rate constant and mechanism of recombination have long been controversial, but great advances have been made during recent years, with the important consequence that the cosmic ray ionization rate in diffuse Clouds is now believed to be higher by an order of magnitude than previously assumed.
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7.
  • Lindgren, Paula, et al. (författare)
  • Putative fossil life in a hydrothermal system of the Dellen impact structure, Sweden
  • 2010
  • Ingår i: International Journal of Astrobiology. - Cambridge : Cambridge University Press. - 1473-5504 .- 1475-3006. ; 9:3, s. 137-146
  • Tidskriftsartikel (refereegranskat)abstract
    • The role of muscarinic acetylcholine receptors (mAChRs) in regulating glucose uptake in L6 skeletal muscle cells was investigated. [H-3]-2-Deoxyglucose uptake was increased in differentiated L6 cells by insulin, acetylcholine, oxotremorine-M and carbachol. mAChR-mediated glucose uptake was inhibited by the AMPK inhibitor Compound C. Whole cell radioligand binding using [H-3]-N-methyl scopolamine chloride identified mAChRs in differentiated but not undifferentiated L6 cells and M-3 mAChR mRNA was detected only in differentiated cells. M-3 mAChRs are Gq-coupled, and cholinergic stimulation by the rnAChR agonists acetylcholine, oxotremorine-M and carbachol increased Ca2+ in differentiated but not undifferentiated L6 cells. This was due to muscarinic but not nicotinic activation as responses were antagonised by the muscarinic antagonist atropine but not the nicotinic antagonist tubocurarine. Western blotting showed that both carbachol and the AMPK activator AICAR increased phosphorylation of the AMPK alpha subunit at Thr172, with responses to carbachol blocked by Compound C and the CaMKK inhibitor STO609 but not by the PI3K inhibitor wortmannin. AICAR-stimulated AMPK phosphorylation was not sensitive to STO-609, confirming that this compound inhibits CaMKK but not the classical AMPK kinase LKB1. The TAK1 inhibitor (5Z)-7-oxozeaenol and the G(i) inhibitor pertussis toxin both failed to block AMPK phosphorylation in response to carbachol. Using CHO-K1 cells stably expressing each of the mAChR subtypes (M-1-M-4), it was determined that only the M-1 and M-3 mAChRs phosphorylate AMPK, confirming a G(q)-dependent mechanism. This study demonstrates that activation of M-3 mAChRs in L6 skeletal muscle cells stimulates glucose uptake via a CaMKK-AMPK-dependent mechanism, independent of the insulin-stimulated pathway.
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8.
  • Masood, Ansar, et al. (författare)
  • Fabrication and tuning soft magnetic and magneto-optical properties of BMGs based Fe-B-Nb-Ni transparent thin films, obtained by Pulsed Laser Deposition
  • 2014
  • Ingår i: International Journal of Astrobiology. - : Springer Nature. - 1473-5504 .- 1475-3006. ; 1649:4
  • Tidskriftsartikel (refereegranskat)abstract
    • We have fabricated by pulse laser deposition very thin (∼5-7 nm) and thick (∼27-408 nm) films of composition Fe66B24Nb4Ni6 on silicon and quartz substrates respectively, and studied their magnetic and magneto-optic properties at room temperature. We find that the thicker films on silicon can be tuned by appropriate thermal annealing to exploit soft magnetic characteristics with low HC, and high MS values. The magnetic hysteretic loops of the as-deposited thicker films on silicon substrates show two interesting characteristics: 1) increase in the coercivity with the film thickness and 2) the onset of a two stage process during the approach to magnetic saturation. The initial in-plane characteristic of the hysteresis loop is followed by a linear anisotropic behavior between remanence and saturation- that changes into square soft-magnetic loops on decreasing the film thickness. By suitable annealing the intrinsic strain disappears at relatively low temperatures (≤200°C); the thicker films can be tailored to exhibit a simple soft-magnetic square loop with low HC. The ∼5-7 nm films deposited on glass are transparent and have been investigated for their magneto-optic properties using Faraday rotation (FR) measurement technique. Very high values of FR in the range 4-20 deg/μm almost linearly dependent on the wavelength of light in the range 405-611 nm are observed. The observed high values of Faraday rotation over a wide range of wavelength of light are useful for the applications as magneto-optic sensors in the UV to visible range.
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9.
  • Mathanlal, Thasshwin, et al. (författare)
  • Subsurface robotic exploration for geomorphology, astrobiology and mining during MINAR6 campaign, Boulby Mine, UK : part I (Rover development)
  • 2020
  • Ingår i: International Journal of Astrobiology. - : Cambridge University Press. - 1473-5504 .- 1475-3006. ; 19:2, s. 110-125
  • Tidskriftsartikel (refereegranskat)abstract
    • Autonomous exploration requires the use of movable platforms that carry a payload of instruments with a certain level of autonomy and communication with the operators. This is particularly challenging in subsurface environments, which may be more dangerous for human access and where communication with the surface is limited. Subsurface robotic exploration, which has been to date very limited, is interesting not only for science but also for cost-effective industrial exploitation of resources and safety assessments in mines. Furthermore, it has a direct application to exploration of extra-terrestrial subsurface environments of astrobiological and geological significance such as caves, lava tubes, impact or volcanic craters and subglacial conduits, for deriving in-situ mineralogical resources and establishing preliminary settlements. However, the technological solutions are generally tailor-made and are therefore considered as costly, fragile and environment-specific, further hindering their extensive and effective applications. To demonstrate the advantages of rover exploration for a broad-community, we have developed KORE (KOmpact Rover for Exploration); a low-cost, re-usable, rover multi-purpose platform. The rover platform has been developed as a technological demonstration for extra-terrestrial subsurface exploration and terrestrial mining operations pertaining to geomorphological mapping, environmental monitoring, gas leak detections and search and rescue operations in case of an accident. The present paper, the first part of a series of two, focuses on describing the development of a robust rover platform to perform dedicated geomorphological, astrobiological and mining tasks. KORE was further tested in the Mine Analogue Research 6 (MINAR6) campaign during September 2018 in the Boulby mine (UK), the second deepest potash mine in Europe at a subsurface depth of 1.1 km, the results of which will be presented in the second paper of this series. KORE is a large, semi-autonomous rover weighing 160 kg with L × W × H dimensions 1.2 m × 0.8 m × 1 m and a payload carrying capacity of 100 kg using 800 W traction power that can power to a maximum speed of 8.4 km h−1. The rover can be easily dismantled in three parts facilitating its transportation to any chosen site of exploration. Presently, the main scientific payloads on KORE are: (1) a three-dimensional mapping camera, (2) a methane detection system, (3) an environmental station capable of monitoring temperature, relative humidity, pressure and gases such as NO2, SO2, H2S, formaldehyde, CO, CO2, O3, O2, volatile organic compounds and particulates and (4) a robotic arm. Moreover, the design of the rover allows for integration of more sensors as per the scientific requirements in future expeditions. At the MINAR6 campaign, the technical readiness of KORE was demonstrated during 6 days of scientific research in the mine, with a total of 22 h of operation.
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10.
  • Mathanlal, Thasshwin, et al. (författare)
  • Subsurface robotic exploration for geomorphology, astrobiology and mining during MINAR6 campaign, Boulby Mine, UK : part II (Results and Discussion)
  • 2021
  • Ingår i: International Journal of Astrobiology. - : Cambridge University Press. - 1473-5504 .- 1475-3006. ; 20:1, s. 93-108
  • Tidskriftsartikel (refereegranskat)abstract
    • Geomorphological studies of the hidden and protected subsurface environments are crucial to obtain a greater insight into the evolution of planetary landforms, hydrology, climate, geology and mineralogy. From an astrobiological point of view subsurface environments are of interest for their potential habitability as they are local environments that are partially or fully shielded from the high levels of space and solar radiation. Furthermore, in the case of Mars, there is an increasing interest in searching for the presence of past or extant life in its subsurface. These applications make it mandatory to investigate equipment and instrumentation that allow for the study of subsurface geomorphology, as well as organic chemical biomarkers, such as biomolecules, carbon, nitrogen and sulphur isotopes, and other biologically significant minerals and gases. Mines on Earth can be used as analogues to investigate the geomorphology of Martian subsurface environments and perform astrobiology studies. With that goal, we have developed a low-cost, robust, remotely operable subsurface rover called KORE (KOmpact Rover for Exploration). This work illustrates the studies of a terrestrial analogue for the exploration of Mars using KORE during the Mine Analogue Research 6 (MINAR 6) campaign with the low-cost 3D mapping technology InXSpace 3D (In situ 3D mapping tool eXploration of space 3D). InXSpace 3D utilizes an RGB-D camera that captures depth information in addition to the RGB data of an image, operating based on the structured light principle capable of providing depth information in mm scale resolution at sub 3 m mapping range. InXSpace 3D is used to capture point clouds of natural and artificial features, thereby obtaining information about geologically relevant structures and also to incorporate them in earth mining safety. We tested two of the dense simultaneous localization and mapping (SLAM) algorithms: Kintinuous and Real-Time Appearance-Based Mapping (RTAB-Map) to check the performance of InXSpace 3D in a dark mine environment. Also, the air accumulation of volatiles such as methane and formaldehyde due to thermogenic and mining process was measured with the environmental station payload on the rover platform, which caters to both astrobiological significance and mine safety. The main conclusions of this work are: (1) a comparison made between the RTAB-Map algorithm and Kintinuous algorithm showed the superiority of Kintinuous algorithm in providing better 3D reconstruction; although RTAB-Map algorithm captured more points than the Kintinuous algorithm in the dark mine environment; (2) a comparison of point cloud images captured with and without lighting conditions had a negligible effect on the surface density of the point clouds; (3) close-range imaging of the polygonal features occurring on the halite walls using InXSpace 3D provided mm-scale resolution to enable further characterization; (4) heuristic algorithms to quickly post-process the 3D point cloud data provided encouraging results for preliminary analyses; (5) we successfully demonstrated the application of KORE to mine safety; and (6) the multi-sensors platform on KORE successfully monitored the accumulated volatiles in the mine atmosphere during its operation. The findings obtained during this KORE campaign could be incorporated in designing and planning future subsurface rover explorations to potential planetary bodies such as Mars with synergistic applications to subsurface environments in mines on Earth.
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