WorldWideScience

Sample records for terrestrial analogue space

  1. Historical space psychology: Early terrestrial explorations as Mars analogues

    Science.gov (United States)

    Suedfeld, Peter

    2010-03-01

    The simulation and analogue environments used by psychologists to circumvent the difficulties of conducting research in space lack many of the unique characteristics of future explorations, especially the mission to Mars. This paper suggests that appropriate additional analogues would be the multi-year maritime and terrestrial explorations that mapped the surface of the Earth in previous centuries. These, like Mars, often involved a hazardous trek through unknown territory, flanked by extended, dangerous voyages to and from the exploration sites. Characteristic issues included interpersonal relationships under prolonged stress, stretches of boredom interspersed with intense work demands, the impossibility of rescue, resupply, or other help from home, chronic danger, physical discomfort and lack of privacy, and the crucial role of the leader. Illustrative examples of one important factor, leadership style, are discussed. The examination of such expeditions can help to identify the psychological stressors that are likely to be experienced by Mars explorers, and can also indicate countermeasures to reduce the damaging impact of those stressors.

  2. Habitability & Astrobiology Research in Mars Terrestrial Analogues

    Science.gov (United States)

    Foing, Bernard

    2014-05-01

    We performed a series of field research campaigns (ILEWG EuroMoonMars) in the extreme Utah desert relevant to Mars environments, and in order to help in the interpretation of Mars missions measurements from orbit (MEX, MRO) or from the surface (MER, MSL), or Moon geochemistry (SMART-1, LRO). We shall give an update on the sample analysis in the context of habitability and astrobiology. Methods & Results: In the frame of ILEWG EuroMoonMars campaigns (2009 to 2013) we deployed at Mars Desert Research station, near Hanksville Utah, a suite of instruments and techniques [A, 1, 2, 9-11] including sample collection, context imaging from remote to local and microscale, drilling, spectrometers and life sensors. We analyzed how geological and geochemical evolution affected local parameters (mineralogy, organics content, environment variations) and the habitability and signature of organics and biota. Among the important findings are the diversity in the composition of soil samples even when collected in close proximity, the low abundances of detectable PAHs and amino acids and the presence of biota of all three domains of life with significant heterogeneity. An extraordinary variety of putative extremophiles was observed [3,4,9]. A dominant factor seems to be soil porosity and lower clay-sized particle content [6-8]. A protocol was developed for sterile sampling, contamination issues, and the diagnostics of biodiversity via PCR and DGGE analysis in soils and rocks samples [10, 11]. We compare the 2009 campaign results [1-9] to new measurements from 2010-2013 campaigns [10-12] relevant to: comparison between remote sensing and in-situ measurements; the study of minerals; the detection of organics and signs of life. Keywords: field analogue research, astrobiology, habitability, life detection, Earth-Moon-Mars, organics References [A] Foing, Stoker & Ehrenfreund (Editors, 2011) "Astrobiology field Research in Moon/Mars Analogue Environments", Special Issue of International

  3. Space Analogue Environments: Are the Populations Comparable?

    Science.gov (United States)

    Sandal, G. M.

    Background: Much of our present understanding about psychology in space is based on studies of groups operating in so-called analogue environments where personnel are exposed to many of the same stressors as those experienced by astronauts in space. One possible problem with extrapolating results is that personnel operating in various hazardous and confined environments might differ in characteristics influencing coping, interaction, and performance. The object of this study was to compare the psychological similarity of these populations in order to get a better understanding of whether this extrapolation is justifiable. The samples investigated include polar crossings (N= 22), personnel on Antarctic research stations (N= 183), several military occupations (N= 187), and participants in space simulation studies (N=20). Methods: Personnel in each of these environments were assessed using the Personality Characteristic Inventory (PCI) and Utrecht Coping List (UCL). The PCI is a multidimensional trait assessment battery that measures various aspects of achievement orientation and social competence. The UCL is a questionnaire designed to assess habitual coping strategies when encountering stressful or demanding situations. Results: Only minor differences in use of habitual coping strategies were evident across the different samples. In relation to personality scores, the military subjects and participants in space simulation studies indicated higher competitiveness and negative instrumentality compared to both the personnel on Antarctic research stations and participants in polar expedition. Among the personnel on Antarctic research stations, significant gender differences were found with women scoring lower on competitiveness, negative instrumentality and impatience/irritability. Compared to the other samples, the participants in polar expeditions were found to be more homogeneous in personality and no significant gender differences were evident on the traits that

  4. Space and Terrestrial Photovoltaics: Synergy and Diversity

    Science.gov (United States)

    Bailey, Sheila; Raffaelle, Ryne; Emery, Keith

    2002-01-01

    A historical view of the research and development in photovoltaics from the perspective of both the terrestrial and the space communities is presented from the early days through the '70s and '80s and the '90s and beyond. The synergy of both communities in the beginning and once again in the present and hopefully future are highlighted, with examples of the important features in each program. The space community which was impressed by the light-weight and reliability of photovoltaics drove much of the early development. Even up to today, nearly every satellites and other scientific space probe that has been launched has included some solar power. However, since the cost of these power systems were only a small fraction of the satellite and launch cost, the use of much of this technology for the terrestrial marketplace was not feasible. It was clear that the focus of the terrestrial community would be best served by reducing costs. This would include addressing a variety of manufacturing issues and raising the rate of production. Success in these programs and a resulting globalization of effort resulted in major strides in the reduction of PV module costs and increased production. Although, the space community derived benefit from some of these advancements, its focus was on pushing the envelope with regard to cell efficiency. The gap between theoretical efficiencies and experimental efficiencies for silicon, gallium arsenide and indium phosphide became almost non-existent. Recent work by both communities have focused on the development thin film cells of amorphous silicon, CuInSe2 and CdTe. These cells hold the promise of lower costs for the terrestrial community as well as possible flexible substrates, better radiation resistance, and higher specific power for the space community. It is predicted that future trends in both communities will be directed toward advances through the application of nanotechnology. A picture is emerging in which the space and

  5. Solar terrestrial coupling through space plasma processes

    International Nuclear Information System (INIS)

    Birn, J.

    2000-01-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project investigates plasma processes that govern the interaction between the solar wind, charged particles ejected from the sun, and the earth's magnetosphere, the region above the ionosphere governed by the terrestrial magnetic field. Primary regions of interest are the regions where different plasma populations interact with each other. These are regions of particularly dynamic plasma behavior, associated with magnetic flux and energy transfer and dynamic energy release. The investigations concerned charged particle transport and energization, and microscopic and macroscopic instabilities in the magnetosphere and adjacent regions. The approaches combined space data analysis with theory and computer simulations

  6. Río Tinto: A Geochemical and Mineralogical Terrestrial Analogue of Mars

    Directory of Open Access Journals (Sweden)

    Ricardo Amils

    2014-09-01

    Full Text Available The geomicrobiological characterization of the water column and sediments of Río Tinto (Huelva, Southwestern Spain have proven the importance of the iron and the sulfur cycles, not only in generating the extreme conditions of the habitat (low pH, high concentration of toxic heavy metals, but also in maintaining the high level of microbial diversity detected in the basin. It has been proven that the extreme acidic conditions of Río Tinto basin are not the product of 5000 years of mining activity in the area, but the consequence of an active underground bioreactor that obtains its energy from the massive sulfidic minerals existing in the Iberian Pyrite Belt. Two drilling projects, MARTE (Mars Astrobiology Research and Technology Experiment (2003–2006 and IPBSL (Iberian Pyrite Belt Subsurface Life Detection (2011–2015, were developed and carried out to provide evidence of subsurface microbial activity and the potential resources that support these activities. The reduced substrates and the oxidants that drive the system appear to come from the rock matrix. These resources need only groundwater to launch diverse microbial metabolisms. The similarities between the vast sulfate and iron oxide deposits on Mars and the main sulfide bioleaching products found in the Tinto basin have given Río Tinto the status of a geochemical and mineralogical Mars terrestrial analogue.

  7. Iberian Pyrite Belt Subsurface Life (IPBSL), a drilling project in a geochemical Mars terrestrial analogue

    Science.gov (United States)

    Amils, R.; Fernández-Remolar, D. C.; Parro, V.; Manfredi, J. A.; Timmis, K.; Oggerin, M.; Sánchez-Román, M.; López, F. J.; Fernández, J. P.; Omoregie, E.; Gómez-Ortiz, D.; Briones, C.; Gómez, F.; García, M.; Rodríguez, N.; Sanz, J. L.

    2012-09-01

    Iberian Pyrite Belt Subsurface Life (IPBSL) is a drilling project specifically designed to characterize the subsurface ecosystems operating in the Iberian Pyrite Belt (IPB), in the area of Peña de Hierro, and responsible of the extreme acidic conditions existing in the Rio Tinto basin [1]. Rio Tinto is considered a good geochemical terrestrial analogue of Mars [2, 3]. A dedicated geophysical characterization of the area selected two drilling sites (4) due to the possible existence of water with high ionic content (low resistivity). Two wells have been drilled in the selected area, BH11 and BH10, of depths of 340 and 620 meters respectively, with recovery of cores and generation of samples in anaerobic and sterile conditions. Preliminary results showed an important alteration of mineral structures associated with the presence of water, with production of expected products from the bacterial oxidation of pyrite (sulfates and ferric iron). Ion chromatography of water soluble compounds from uncontaminated samples showed the existence of putative electron donors (ferrous iron, nitrite in addition of the metal sulfides), electron acceptors (sulfate, nitrate, ferric iron) as well as variable concentration of metabolic organic acids (mainly acetate, formate, propionate and oxalate), which are strong signals of the presence of active subsurface ecosystem associated to the high sulfidic mineral content of the IPB. The system is driven by oxidants that appear to be provided by the rock matrix, only groundwater is needed to launch microbial metabolism. The geological, geomicrobiological and molecular biology analysis which are under way, should allow the characterization of this ecosystem of paramount interest in the design of an astrobiological underground Mars exploration mission in the near future.

  8. Survival rates of some terrestrial microorganisms under simulated space conditions

    Science.gov (United States)

    Koike, J.; Oshima, T.; Koike, K. A.; Taguchi, H.; Tanaka, R.; Nishimura, K.; Miyaji, M.

    1992-10-01

    In connection with planetary quarantine, we have been studying the survival rates of nine species of terrestrial microorganisms (viruses, bacteria, yeasts, fungi, etc.) under simulated interstellar conditions. If common terrestrial microorganisms cannot survive in space even for short periods, we can greatly reduce expenditure for sterilizing space probes. The interstellar environment in the solar system has been simulated by low temperature, high vacuum (77 k, 4 × 10-6 torr), and protons irradiation from a Van de Graaff generator. After exposure to a barrage of protons corresponding to about 250 years of irradiation in solar space, Tobacco mosaic virus. Bacillus subtilis spores, Aspergillus niger spores, and Clostridium mangenoti spores showed survival rates of 82%, 45%, 28%, and 25%, respectively. Furthermore, pathogenic Candida albicans showed 7% survival after irradiation corresponding to about 60 years in space.

  9. Nanotechnologies and regenerative medical approaches for space and terrestrial medicine.

    Science.gov (United States)

    Grattoni, Alessandro; Tasciotti, Ennio; Fine, Daniel; Fernandez-Moure, Joseph S; Sakamoto, Jason; Hu, Ye; Weiner, Bradley; Ferrari, Mauro; Parazynski, Scott

    2012-11-01

    One purpose of the International Space Station (ISS) is to explore powerful new areas of biomedical science in microgravity. Recent advances in nanotechnology applied to medicine--what we now refer to as nano-medicine--and regenerative medicine have enormous untapped potential for future space and terrestrial medical applications. Novel means for drug delivery and nanoscale screening tools will one day benefit astronauts venturing to Mars and places beyond, while the space laboratory will foster advances in nanotechnologies for diagnostic and therapeutic tools to help our patients here on Earth. Herein we review a series of nanotechnologies and selected regenerative medical approaches and highlight key areas of ongoing and future investigation that will benefit both space and terrestrial medicine. These studies target significant areas of human disease such as osteoporosis, diabetes, radiation injury, and many others.

  10. The Manicouagan impact structure as a terrestrial analogue site for lunar and martian planetary science

    Science.gov (United States)

    Spray, John G.; Thompson, Lucy M.; Biren, Marc B.; O'Connell-Cooper, Catherine

    2010-03-01

    The 90 km diameter, late Triassic Manicouagan impact structure of Québec, Canada, is a well-preserved, undeformed complex crater possessing an anorthositic central uplift and a 55 km diameter melt sheet. As such, it provides a valuable terrestrial analogue for impact structures developed on other planetary bodies, especially the Moon and Mars, which are currently the focus of exploration initiatives. The scientific value of Manicouagan has recently been enhanced due to the production, between 1994 and 2006, of ˜18 km of drill core from 38 holes by the mineral exploration industry. Three of these holes are in excess of 1.5 km deep, with the deepest reaching 1.8 km. Here we combine recent field work, sampling and the drill core data with previous knowledge to provide insight into processes occurring at Manicouagan and, by inference, within extraterrestrial impact structures. Four areas of comparative planetology are discussed: impact melt sheets, central uplifts, impact-generated hydrothermal regimes and footwall breccias. Human training and instrument testing opportunities are also considered. The drill core reveals that the impact melt and clast-bearing impact melts in the centre of the structure reach thicknesses of 1.4 km. The 1.1 km thick impact melt has undergone differentiation to yield a lower monzodiorite, a transitional quartz monzodiorite and an upper quartz monzonite sequence. This calls into question the previous citing of Manicouagan as an exemplar of a relatively large crater possessing an undifferentiated melt sheet, which was used as a rationale for assigning different composition lunar impact melts and clast-bearing impact melts to separate cratering events. The predominantly anorthositic central uplift at Manicouagan is comparable to certain lunar highlands material, with morphometric analogies to the King, Tycho, Pythagoras, Jackson, and Copernicus impact structures, which have similar diameters and uplift structure. Excellent exposure of the

  11. Observing terrestrial ecosystems and the carbon cycle from space

    Energy Technology Data Exchange (ETDEWEB)

    Schimel, David [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Pavlick, Ryan [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Fisher, Joshua B. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Asner, Gregory P. [Department of Global Ecology, Carnegie Institution for Science, 260 Panama St. Stanford CA 94305 USA; Saatchi, Sassan [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Townsend, Philip [University of Wisconsin-Madison, Madison WI 53706 USA; Miller, Charles [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Frankenberg, Christian [Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA 91101 USA; Hibbard, Kathy [Pacific Northwest National Laboratory, PO Box 999 MSIN: K9-34 Richland WA 99352 USA; Cox, Peter [College of Engineering, Mathematics and Physical Sciences, University of Exeter, North Park Road Streatham Campus Harrison Building Exeter EX4 4QF UK

    2015-02-06

    Modeled terrestrial ecosystem and carbon cycle feedbacks contribute substantial uncertainty to projections of future climate. The limitations of current observing networks contribute to this uncertainty. Here we present a current climatology of global model predictions and observations for photosynthesis, biomass, plant diversity and plant functional diversity. Carbon cycle tipping points occur in terrestrial regions where fluxes or stocks are largest, and where biological variability is highest, the tropics and Arctic/Boreal zones. Global observations are predominately in the mid-latitudes and are sparse in high and low latitude ecosystems. Observing and forecasting ecosystem change requires sustained observations of sufficient density in time and space in critical regions. Using data and theory available now, we can develop a strategy to detect and forecast terrestrial carbon cycle-climate interactions, by combining in situ and remote techniques.

  12. Martian Feeling: An Analogue Study to Simulate a Round-Trip to Mars using the International Space Station

    Science.gov (United States)

    Felix, C. V.; Gini, A.

    When talking about human space exploration, Mars missions are always present. It is clear that sooner or later, humanity will take this adventure. Arguably the most important aspect to consider for the success of such an endeavour is the human element. The safety of the crew throughout a Martian mission is a top priority for all space agencies. Therefore, such a mission should not take place until all the risks have been fully understood and mitigated. A mission to Mars presents unique human and technological challenges in terms of isolation, confinement, autonomy, reliance on mission control, communication delays and adaptation to different gravity levels. Analogue environments provide the safest way to simulate these conditions, mitigate the risks and evaluate the effects of long-term space travel on the crew. Martian Feeling is one of nine analogue studies, from the Mars Analogue Path (MAP) report [1], proposed by the TP Analogue group of ISU Masters class 2010. It is an integrated analogue study which simulates the psychological, physiological and operational conditions that an international, six-person, mixed gender crew would experience on a mission to Mars. Set both onboard the International Space Station (ISS) and on Earth, the Martian Feeling study will perform a ``dress rehearsal'' of a mission to Mars. The study proposes to test both human performance and operational procedures in a cost-effective manner. Since Low Earth Orbit (LEO) is more accessible than other space-based locations, an analogue studies in LEO would provide the required level of realism to a simulated transit mission to Mars. The sustained presence of microgravity and other elements of true spaceflight are features of LEO that are neither currently feasible nor possible to study in terrestrial analogue sites. International collaboration, economics, legal and ethical issues were considered when the study was proposed. As an example of international collaboration, the ISS would

  13. Evaluation of meteorites as habitats for terrestrial microorganisms: Results from the Nullarbor Plain, Australia, a Mars analogue site

    Science.gov (United States)

    Tait, Alastair W.; Wilson, Siobhan A.; Tomkins, Andrew G.; Gagen, Emma J.; Fallon, Stewart J.; Southam, Gordon

    2017-10-01

    Unambiguous identification of biosignatures on Mars requires access to well-characterized, long-lasting geochemical standards at the planet's surface that can be modified by theoretical martian life. Ordinary chondrites, which are ancient meteorites that commonly fall to the surface of Mars and Earth, have well-characterized, narrow ranges in trace element and isotope geochemistry compared to martian rocks. Given that their mineralogy is more attractive to known chemolithotrophic life than the basaltic rocks that dominate the martian surface, exogenic rocks (e.g., chondritic meteorites) may be good places to look for signs of prior life endemic to Mars. In this study, we show that ordinary chondrites, collected from the arid Australian Nullarbor Plain, are commonly colonized and inhabited by terrestrial microorganisms that are endemic to this Mars analogue site. These terrestrial endolithic and chasmolithic microbial contaminants are commonly found in close association with hygroscopic veins of gypsum and Mg-calcite, which have formed within cracks penetrating deep into the meteorites. Terrestrial bacteria are observed within corrosion cavities, where troilite (FeS) oxidation has produced jarosite [KFe3(SO4)2(OH)6]. Where terrestrial microorganisms have colonized primary silicate minerals and secondary calcite, these mineral surfaces are heavily etched. Our results show that inhabitation of meteorites by terrestrial microorganisms in arid environments relies upon humidity and pH regulation by minerals. Furthermore, microbial colonization affects the weathering of meteorites and production of sulfate, carbonate, Fe-oxide and smectite minerals that can preserve chemical and isotopic biosignatures for thousands to millions of years on Earth. Meteorites are thus habitable by terrestrial microorganisms, even under highly desiccating environmental conditions of relevance to Mars. They may therefore be useful as chemical and isotopic ;standards; that preserve evidence of

  14. Terrestrial analogues models based on MOURA magnetometer data. Application to Gusev crater and Apollinaris volcano

    Science.gov (United States)

    Díaz-Michelena, Marina; Cerdán, Miguel Felipe; Ramírez-Nicolás, María; Sánchez-Cano, Beatríz; Sánchez-Bayton, Marina; Kilian, Rolf

    2014-05-01

    Sometimes it is a problem to determine whether a crater was formed by an explosive volcanic event or a meteorite impact. This issue is of interest even on Earth where geological features are often masked by erosion or vegetation and for the interpretation of ancient craters on other planets or moons, where the geological context is not clearly determined. Thus we propose a geophysical modelling approach to study the formation of such craters with potential application to Mars, whose surface is fully covered with craters. The evolution of this study might shed more light over the martian ancient geodynamo. The Earth provides many examples to develop models for the geological features of such craters since it is feasible to perform magnetic and gravity surveys at different altitudes, and therefore to have information on different surface scales. The models developed with real satellite, airborne and on ground data on Earth (Moar, 2004) can be extrapolated to other bodies, like Mars or the Moon, where only satellite and limited ground data are available. In the present study, surveys are mainly based on vector data from surveys with MOURA magnetometer developed by INTA for Mars MetNet mission. Since the ambient conditions of Mars are so extreme, MOURA is capable to withstand the extreme conditions of the terrestrial analogues. The models of craters are based on typical crater structures proposed by Lorenz (2003) and Grieve (2006), where distinct susceptibilities and remanent magnetization have been attributed to different volcanic or impact related rock units (bedded upper diatreme facies and unbedded lower diatreme facies, tephra rims and ejecta blankets, high pressures and temperature volumes, etc) and target rocks. The analysis of the scalar magnetic potential and its harmonics can help in the interpretation of the origin of these craters and their geological context by means of the magnetic signature. In this study, it will be presented the correlation between

  15. Studies of fracture network geometry of reservoir outcrop analogues from terrestrial lidar data: attempts to quantify spatial variations of fracture characteristics

    Science.gov (United States)

    Vsemirnova, E. A.; Jones, R. R.; McCaffrey, K. J. W.

    2012-04-01

    We describe studies analysing terrestrial lidar datasets of fracture systems from a range of reservoir analogues in clastic and carbonate lithologies that represent geological analogues of offshore hydrocarbon reservoirs for the UK continental shelf. As fracture networks (observed here from centimetre to kilometre scale) can significantly affect the permeability of a fractured reservoir, the definition of fracture network geometry at various scales has become an important goal of structural analysis. The main aim of the study has been to extend the investigation of fracture networks in order to quantify spatial variations in fracture parameters in a variety of lithologies. The datasets were pre-processed using RiSCAN PRO software, and then re-sampled and filtered to derive characteristics which are traditionally measured from outcrops, including size distributions, fracture spacing and clustering statistics. This type of analysis can significantly reduce the uncertainty associated with some field fracture network measurements. The digitised fracture networks datasets are then used to investigate various aspects of spatial heterogeneity. A series of fracture maps (joints and faults) were generated at different scales, and fracture trends were studied to test scale dependency of fracture orientations. Multiscale trend analysis was then applied to describe the trend structure of the fracture networks.

  16. Advancing Translational Space Research Through Biospecimen Sharing: Amplified Impact of Studies Utilizing Analogue Space Platforms

    Science.gov (United States)

    Staten, B.; Moyer, E.; Vizir, V.; Gompf, H.; Hoban-Higgins, T.; Lewis, L.; Ronca, A.; Fuller, C. A.

    2016-01-01

    Biospecimen Sharing Programs (BSPs) have been organized by NASA Ames Research Center since the 1960s with the goal of maximizing utilization and scientific return from rare, complex and costly spaceflight experiments. BSPs involve acquiring otherwise unused biological specimens from primary space research experiments for distribution to secondary experiments. Here we describe a collaboration leveraging Ames expertise in biospecimen sharing to magnify the scientific impact of research informing astronaut health funded by the NASA Human Research Program (HRP) Human Health Countermeasures (HHC) Element. The concept expands biospecimen sharing to one-off ground-based studies utilizing analogue space platforms (e.g., Hindlimb Unloading (HLU), Artificial Gravity) for rodent experiments, thereby significantly broadening the range of research opportunities with translational relevance for protecting human health in space and on Earth.

  17. Leveraging Terrestrial Industry for Utilization of Space Resources

    Science.gov (United States)

    Sanders, Gerald B.; Linne, Diane L.; Starr, Stan O.; Boucher, Dale

    2017-01-01

    NASA's Journey to Mars: Pioneering Next Steps in Space Exploration released in October of 2015 states that NASA is working toward the capability to work, operate, and sustainably live safely beyond Earth. To progress from our current "Earth-Reliant" approach to exploration and eventually become "Earth Independent", we need to first identify resources in space and then learn to use and harvest them to minimize logistics from Earth, reduce costs, and enable sustainable and affordable space transportation and surface operations. Known as In Situ Resource Utilization (ISRU), the collection and conversion of space resources into products such as propellants, fuel cell reactants, and life support consumables can greatly reduce the mass, cost, and risk of space exploration. Also, the ability to perform civil engineering, construction, and manufacturing at sites of exploration can also allow for increased crew safety and sustainable growth in critical infrastructure. Much of what NASA wants to do on the Moon and Mars with respect to harnessing and utilizing space resources has been performed and perfected on Earth over the centuries. While minimizing mass and operating in the vacuum of space may be unique challenges to NASA, both terrestrial industry and NASA face many of the same challenges associated with operating in severe environments, minimizing maintenance and logistics, maximizing performance per unit mass and volume, performing remote and autonomous operations, and integrating hardware from many vendors and countries. In the end, both NASA and terrestrial industry need to obtain a return on the investment for the development and deployment of these capabilities. This paper will first examine what is ISRU and what are the space resources of interest. The paper will than discuss what are NASA's approach, life cycle, and economic considerations for implementing ISRU. The paper will outline the site and infrastructure needs associated with a phased implementation of

  18. Radiation safety standards: space hazards vs. terrestrial hazards

    International Nuclear Information System (INIS)

    Sinclair, W.K.

    1983-01-01

    Policies regarding the setting of standards for radiation exposure for astronauts and other workers in space are discussed. The first recommendations for dose limitation and the underlying philosophy of these recommendations, which were put out in 1970, are examined, and consequences for the standards if the same philosophy of allowing a doubling in overall cancer risk for males aged 30-35 over a 20-year period were applied to more recent risk estimates are calculated, leading to values about a factor of 4 below the 1970 recommendation. Standards set since 1930 for terrestrial occupational exposures, which lead to a maximum lifetime risk of about 2.3 percent, are then considered, and the space and terrestrial exposure risks for fatal cancers at maximum lifetime dose are compared with industrial accidental death rates. Attention is also given to the question of the potential effects of HZE particles in space and to the possibility that HZE particle effects, rather than radiation carcinogenesis, might be the limiting factor. 17 references

  19. Terrestrial Applications of Extreme Environment Stirling Space Power Systems

    Science.gov (United States)

    Dyson, Rodger. W.

    2012-01-01

    NASA has been developing power systems capable of long-term operation in extreme environments such as the surface of Venus. This technology can use any external heat source to efficiently provide electrical power and cooling; and it is designed to be extremely efficient and reliable for extended space missions. Terrestrial applications include: use in electric hybrid vehicles; distributed home co-generation/cooling; and quiet recreational vehicle power generation. This technology can reduce environmental emissions, petroleum consumption, and noise while eliminating maintenance and environmental damage from automotive fluids such as oil lubricants and air conditioning coolant. This report will provide an overview of this new technology and its applications.

  20. Reliability program requirements for Space and Terrestrial Nuclear Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    1982-10-01

    The objectives of the reliability program requirements described in this report are (1) to provide contractors with an outline of the reliability requirements established by the Department of Energy (DOE) in the areas of design, development, production, testing, and acceptance of space and terrestrial nuclear systems hardware, and (2) to guide the contractor in meeting these requirements. This publication or particular portions of it is applicable as specified in the contract. Whether the contractors/subcontractors are subject to all the requirements or only to part of them will be specified by contract, program letter, or by the contract statement-of-work.

  1. Astrobiology through the ages of Mars: the study of terrestrial analogues to understand the habitability of Mars.

    Science.gov (United States)

    Fairén, Alberto G; Davila, Alfonso F; Lim, Darlene; Bramall, Nathan; Bonaccorsi, Rosalba; Zavaleta, Jhony; Uceda, Esther R; Stoker, Carol; Wierzchos, Jacek; Dohm, James M; Amils, Ricardo; Andersen, Dale; McKay, Christopher P

    2010-10-01

    Mars has undergone three main climatic stages throughout its geological history, beginning with a water-rich epoch, followed by a cold and semi-arid era, and transitioning into present-day arid and very cold desert conditions. These global climatic eras also represent three different stages of planetary habitability: an early, potentially habitable stage when the basic requisites for life as we know it were present (liquid water and energy); an intermediate extreme stage, when liquid solutions became scarce or very challenging for life; and the most recent stage during which conditions on the surface have been largely uninhabitable, except perhaps in some isolated niches. Our understanding of the evolution of Mars is now sufficient to assign specific terrestrial environments to each of these periods. Through the study of Mars terrestrial analogues, we have assessed and constrained the habitability conditions for each of these stages, the geochemistry of the surface, and the likelihood for the preservation of organic and inorganic biosignatures. The study of these analog environments provides important information to better understand past and current mission results as well as to support the design and selection of instruments and the planning for future exploratory missions to Mars.

  2. Novel peptide chemistry in terrestrial animals: natural luciferin analogues from the bioluminescent earthworm Fridericia heliota.

    Science.gov (United States)

    Dubinnyi, Maxim A; Tsarkova, Aleksandra S; Petushkov, Valentin N; Kaskova, Zinaida M; Rodionova, Natalja S; Kovalchuk, Sergey I; Ziganshin, Rustam H; Baranov, Mikhail S; Mineev, Konstantin S; Yampolsky, Ilia V

    2015-03-02

    We report isolation and structure elucidation of AsLn5, AsLn7, AsLn11 and AsLn12: novel luciferin analogs from the bioluminescent earthworm Fridericia heliota. They were found to be highly unusual modified peptides, comprising either of the two tyrosine-derived chromophores, CompX or CompY and a set of amino acids, including threonine, gamma-aminobutyric acid, homoarginine, and unsymmetrical N,N-dimethylarginine. These natural compounds represent a unique peptide chemistry found in terrestrial animals and rise novel questions concerning their biosynthetic origin. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Terrestrial Micro Renewable Energy Applications of Space Technology

    Science.gov (United States)

    Komerath, N. M.; Komerath, P. P.

    This paper explores the synergy between technologies intended for extraterrestrial in situ resource utilization and those for terrestrial mass-market micro renewable power generation systems. The case for a micro renewable energy architecture is presented. The obstacles hindering market success are summarized, along with opportunities from recent demonstrations suggesting that the public appetite for sophisticated technology worldwide may be underappreciated by technical researchers. Technical innovations from space research are summarized along with estimates of possible conversion efficiencies. It is argued that the cost-effectiveness of micro power generation must be viewed through the value of the first few watts of available power, rather than the marginal cost per kilowatt-hour of electric power from utility power grids. This leads to the finding that the actual target cost per unit power, and efficiency, are well within reach of space technology products. Hybrid systems integrating power extraction from multiple resources, and adaptable for multiple applications, can break through mass market price barriers. Recent work to develop learning resources and test beds as part of a Micro Renewable Energy Laboratory is summarized.

  4. Extreme Environment Technologies for Space and Terrestrial Applications

    Science.gov (United States)

    Balint, Tibor S.; Cutts, James A.; Kolawa, Elizabeth A.; Peterson, Craig E.

    2008-01-01

    Over the next decades, NASA's planned solar system exploration missions are targeting planets, moons and small bodies, where spacecraft would be expected to encounter diverse extreme environmental (EE) conditions throughout their mission phases. These EE conditions are often coupled. For instance, near the surface of Venus and in the deep atmospheres of giant planets, probes would experience high temperatures and pressures. In the Jovian system low temperatures are coupled with high radiation. Other environments include thermal cycling, and corrosion. Mission operations could also introduce extreme conditions, due to atmospheric entry heat flux and deceleration. Some of these EE conditions are not unique to space missions; they can be encountered by terrestrial assets from the fields of defense,oil and gas, aerospace, and automotive industries. In this paper we outline the findings of NASA's Extreme Environments Study Team, including discussions on state of the art and emerging capabilities related to environmental protection, tolerance and operations in EEs. We will also highlight cross cutting EE mitigation technologies, for example, between high g-load tolerant impactors for Europa and instrumented projectiles on Earth; high temperature electronics sensors on Jupiter deep probes and sensors inside jet engines; and pressure vessel technologies for Venus probes and sea bottom monitors. We will argue that synergistic development programs between these fields could be highly beneficial and cost effective for the various agencies and industries. Some of these environments, however, are specific to space and thus the related technology developments should be spear headed by NASA with collaboration from industry and academia.

  5. Quantitative Investigations of Polygonal Ground in Continental Antarctica: Terrestrial Analogues for Polygons on Mars

    Science.gov (United States)

    Sassenroth, Cynthia; Hauber, Ernst; Schmitz, Nicole; de Vera, Jean Pierre

    2017-04-01

    Polygonally fractured ground is widespread at middle and high latitudes on Mars. The latitude-dependence and the morphologic similarity to terrestrial patterned ground in permafrost regions may indicate a formation as thermal contraction cracks, but the exact formation mechanisms are still unclear. In particular, it is debated whether freeze-thaw processes and liquid water are required to generate the observed features. This study quantitatively investigates polygonal networks in ice-free parts of continental Antarctica to help distinguishing between different hypotheses of their origin on Mars. The study site is located in the Helliwell Hills in Northern Victoria Land ( 71.73°S/161.38°E) and was visited in the framework of the GANOVEX XI expedition during the austral summer of 2015/2016. The local bedrock consists mostly of sediments (sandstones) of the Beacon Supergroup and mafic igneous intrusions (Ferrar Dolerites). The surfaces are covered by glacial drift consisting of clasts with diverse lithologies. Thermal contraction cracks are ubiquitous. We mapped polygons in the northern part of Helliwell Hills in a GIS environment on the basis of high-resolution satellite images with a pixel size of 50 cm. The measured spatial parameters include polygon area, perimeter, length, width, circularity and aspect. We also analyzed the connectivity of enclosed polygons within a polygon network. The polygons do not display significant local relief, but overall the polygon centers are slightly higher than the bounding cracks (i.e. high-center polygons). Sizes of polygons can vary widely, dependent on the geographical location, between 10m2 and >900m2. In planar and level areas, thermal contraction cracks tend to be well connected as hexagonal or irregular polygonal networks without a preferred alignment. In contrast, polygonal networks on slopes form elongated, orthogonal primary cracks, which are either parallel or transverse to the steepest topographic gradient. During

  6. Tracking Changes in Iron Mineralogy Through Time in Gale Crater and Terrestrial Analogues

    Science.gov (United States)

    Sheppard, R.; Milliken, R.; Russell, J. M.

    2017-12-01

    Iron and other redox-sensitive elements measured in ancient mudstones of Gale Crater, Mars by the Curiosity rover can provide information on past climate and interactions between water and the early atmosphere. Preserved ferrous mineralogy can constrain lake bottom water conditions and potentially the relative position of the oxycline and/or shoreline through the stratigraphic section. Multiple oxidation states in a given assemblage may also indicate a potential energy source for microbes. The X-ray amorphous fraction of all rocks measured in Gale Crater to date is also enigmatic: it can constitute up to 50 wt% of the sediment but the precise composition and formation conditions are unknown. Features similar to those in the martian mudstones are seen in sediments from the terrestrial redox-stratified Lake Towuti, including alternating ferrous and ferric mineralogy and an abundant Fe-rich X-ray amorphous phase. To constrain conditions in the water column and early diagenetic processes, we present trends in chemistry and mineralogy for sediment acquired from soils in the mafic/ultramafic catchment and lake bottom/core samples. The soils contain high abundances of crystalline Fe-oxides (e.g. magnetite, goethite, hematite), whereas sediment from the very surface of the lake bottom maintain high Fe but not in crystalline form based on XRD. This suggests Fe is being rapidly cycled to form amorphous phases after entering the lake. Sequential extractions to isolate highly reactive iron (e.g. ferrihydrite) will be used to confirm the relative abundance of poorly crystalline phases in catchment versus lake sediment. Sediments from a 150 m core representing 1 Myr lake history also maintain high Fe content and distinct alternating bands of red and green sediment, but there are no crystalline Fe-oxides discernible in XRD data. The process(es) and timescale for this switching is not yet known, but understanding the conditions that allow ferrous vs. ferric iron to form, and what

  7. Covariant differential calculus on quantum Minkowski space and the q-analogue of Dirac equation

    International Nuclear Information System (INIS)

    Song Xingchang; Academia Sinica, Beijing

    1992-01-01

    The covariant differential calculus on the quantum Minkowski space is presented with the help of the generalized Wess-Zumino method and the quantum Pauli matrices and quantum Dirac matrices are constructed parallel to those in the classical case. Combining these two aspects a q-analogue of Dirac equation follows directly. (orig.)

  8. Smart Grid Development Issues for Terrestrial and Space Applications

    Science.gov (United States)

    Soeder, James F.

    2014-01-01

    The development of the so called Smart Grid has as many definitions as individuals working in the area. Based on the technology or technologies that are of interest, be it high speed communication, renewable generation, smart meters, energy storage, advanced sensors, etc. they can become the individual defining characteristic of the Smart Grid. In reality the smart grid encompasses all of these items and quite at bit more. This discussion attempts to look at what the needs are for the grid of the future, such as the issues of increased power flow capability, use of renewable energy, increased security and efficiency and common power and data standards. It also shows how many of these issues are common with the needs of NASA for future exploration programs. A common theme to address both terrestrial and space exploration issues is to develop micro-grids that advertise the ability to enable the load leveling of large power generation facilities. However, for microgrids to realize their promise there needs to a holistic systems approach to their development and integration. The overall system integration issues are presented along with potential solution methodologies.

  9. Subsurface geomicrobiology in a Mars terrestrial analogue, Río Tinto (SW, Spain)

    Science.gov (United States)

    Amils, R.; Fernández-Remolar, D.; Gómez, F.; González-Toril, E.; Rodríguez, N.; Prieto-Ballesteros, O.; Sanz, J. L.; Díaz, E.; Stoker, C.

    2008-09-01

    carbon or transient oxygen. These results suggest that multiple energy sources are available from sulfide-mineral weathering to support microbial metabolism, even in the absence of atmospheric oxygen. [1] Stevens, T.O and McKinley, J.P. (1995) Scienc,, 270, 450-454. [2] Amis, R. et al. (2007) Planet Space Sci, 55, 370- 381. [3] Fernández-Remolar, D. et al. (2005) Earth Planet Sci Lett, 240, 149-167. [4] Amils, R. et al. (2008) Microbiology of Extreme Soils, 205-223.

  10. Anesthesia and critical-care delivery in weightlessness: A challenge for research in parabolic flight analogue space surgery studies

    Science.gov (United States)

    Ball, Chad G.; Keaney, Marilyn A.; Chun, Rosaleen; Groleau, Michelle; Tyssen, Michelle; Keyte, Jennifer; Broderick, Timothy J.; Kirkpatrick, Andrew W.

    2010-03-01

    BackgroundMultiple nations are actively pursuing manned exploration of space beyond low-earth orbit. The responsibility to improve surgical care for spaceflight is substantial. Although the use of parabolic flight as a terrestrial analogue to study surgery in weightlessness (0 g) is well described, minimal data is available to guide the appropriate delivery of anesthesia. After studying anesthetized pigs in a 0 g parabolic flight environment, our group developed a comprehensive protocol describing prolonged anesthesia in a parabolic flight analogue space surgery study (PFASSS). Novel challenges included a physically remote vivarium, prolonged (>10 h) anesthetic requirements, and the provision of veterinary operating room/intensive care unit (ICU) equivalency on-board an aircraft with physical dimensions of ethical approval, multiple ground laboratory sessions were conducted with combinations of anesthetic, pre-medication, and induction protocols on Yorkshire-cross specific pathogen-free (SPF) pigs. Several constant rate infusion (CRI) intravenous anesthetic combinations were tested. In each regimen, opioids were administered to ensure analgesia. Ventilation was supported mechanically with blended gradients of oxygen. The best performing terrestrial 1 g regime was flight tested in parabolic flight for its effectiveness in sustaining optimal and prolonged anesthesia, analgesia, and maintaining hemodynamic stability. Each flight day, a fully anesthetized, ventilated, and surgically instrumented pig was transported to the Flight Research Laboratory (FRL) in a temperature-controlled animal ambulance. A modular on-board surgical/ICU suite with appropriate anesthesia/ICU and surgical support capabilities was employed. ResultsThe mean duration of anesthesia (per flight day) was 10.28 h over four consecutive days. A barbiturate and ketamine-based CRI anesthetic regimen supplemented with narcotic analgesia by bolus administration offered the greatest prolonged hemodynamic

  11. Innovation in Deep Space Habitat Interior Design: Lessons Learned From Small Space Design in Terrestrial Architecture

    Science.gov (United States)

    Simon, Matthew A.; Toups, Larry

    2014-01-01

    Increased public awareness of carbon footprints, crowding in urban areas, and rising housing costs have spawned a 'small house movement' in the housing industry. Members of this movement desire small, yet highly functional residences which are both affordable and sensitive to consumer comfort standards. In order to create comfortable, minimum-volume interiors, recent advances have been made in furniture design and approaches to interior layout that improve both space utilization and encourage multi-functional design for small homes, apartments, naval, and recreational vehicles. Design efforts in this evolving niche of terrestrial architecture can provide useful insights leading to innovation and efficiency in the design of space habitats for future human space exploration missions. This paper highlights many of the cross-cutting architectural solutions used in small space design which are applicable to the spacecraft interior design problem. Specific solutions discussed include reconfigurable, multi-purpose spaces; collapsible or transformable furniture; multi-purpose accommodations; efficient, space saving appliances; stowable and mobile workstations; and the miniaturization of electronics and computing hardware. For each of these design features, descriptions of how they save interior volume or mitigate other small space issues such as confinement stress or crowding are discussed. Finally, recommendations are provided to provide guidance for future designs and identify potential collaborations with the small spaces design community.

  12. Comparison of Jovian and Terrestrial Lightning as Observed from Space

    Science.gov (United States)

    Dyudina, Ulyana A.; Ingersoll, A. P.; Boccippio, Dennis; Arnold, James E. (Technical Monitor)

    2001-01-01

    We compare the images of Jovian lightning taken by Galileo spacecraft with the images of terrestrial lightning observed by Lightning Imaging Spectrometer (LIS) onboard the TERRA spacecraft. Both data sets have good spatial resolution: Galileo's pixel is 25 km, or about half the atmospheric scale height, LIS pixel is 3-6 km, also about half of the scale height. This good resolution allows us to see that both Jovian and terrestrial lightning spots look diffuse because of the scattering in the clouds above. Previously we used the appearance of the diffuse spots on Jupiter to model lightning depths and the opacity and shape of the overlying clouds (Dyudina and Ingersoll, 2000). The comparison with LIS data allowed us to verify that the model is valid for terrestrial lightning. The irregular shapes of large terrestrial lightning suggests 30-km scale horizontal bolts. On Jupiter the spots, projected onto the horizontal plane, are nearly circular suggesting that the large size of the spots is mostly due to the horizontal diffusion of the photons scattered in the clouds. Unlike the Galileo observations, LIS has fine temporal resolution of 2 ms, or about 250 frames per single lightning flash. We will discuss the temporal evolution of terrestrial flashes and its implications for Jupiter.

  13. A theory of ionospheric dynamo for complete model of terrestrial space at high and medium latitudes

    International Nuclear Information System (INIS)

    Vardanyan, Yu.S.

    1992-01-01

    A multi-layer model of terrestrial cosmic space at high and medium latitudes is considered in the approximation of infinite conductivity of the Earth taking into account the ambipolar diffusion processes in upper layers of ionosphere. 14 refs

  14. Detection of macromolecules in desert cyanobacteria mixed with a lunar mineral analogue after space simulations.

    Science.gov (United States)

    Baqué, Mickael; Verseux, Cyprien; Rabbow, Elke; de Vera, Jean-Pierre Paul; Billi, Daniela

    2014-09-01

    In the context of future exposure missions in Low Earth Orbit and possibly on the Moon, two desert strains of the cyanobacterium Chroococcidiopsis, strains CCMEE 029 and 057, mixed or not with a lunar mineral analogue, were exposed to fractionated fluencies of UVC and polychromatic UV (200-400 nm) and to space vacuum. These experiments were carried out within the framework of the BIOMEX (BIOlogy and Mars EXperiment) project, which aims at broadening our knowledge of mineral-microorganism interaction and the stability/degradation of their macromolecules when exposed to space and simulated Martian conditions. The presence of mineral analogues provided a protective effect, preserving survivability and integrity of DNA and photosynthetic pigments, as revealed by testing colony-forming abilities, performing PCR-based assays and using confocal laser scanning microscopy. In particular, DNA and pigments were still detectable after 500 kJ/m(2) of polychromatic UV and space vacuum (10(-4) Pa), corresponding to conditions expected during one-year exposure in Low Earth Orbit on board the EXPOSE-R2 platform in the presence of 0.1 % Neutral Density (ND) filter. After exposure to high UV fluencies (800 MJ/m(2)) in the presence of minerals, however, altered fluorescence emission spectrum of the photosynthetic pigments were detected, whereas DNA was still amplified by PCR. The present paper considers the implications of such findings for the detection of biosignatures in extraterrestrial conditions and for putative future lunar missions.

  15. A dual use case study of space technologies for terrestrial medical applications (Conference Presentation)

    Science.gov (United States)

    Cozmuta, Ioana

    2017-05-01

    Many challenges exist in understanding the human body as a whole, its adaptability, its resilience, its immunological response, its healing and regeneration power. New knowledge is usually obtained by exploring unique conditions and environments and space is one such variable. Primarily, these attributes have been studied in space for the purpose of understanding the effect of the space environment on long duration space travel. However a myriad of lessons learned have emerged that are important for terrestrial medicine problems such as cardiovascular changes, intracranial pressure changes, vision changes, reduced immunity, etc. For medical study purposes, the changes induced by the space environment on the human body are in general fast and predictable; they persist while in the space environment but also revert to the initial pre-flight healthy state upon return to Earth. This provides a unique cycle to study wellness and disease prediction as well as to develop more effective countermeasures for the benefit of people on earth. At a scientific level, the environment of space can be used to develop new lines of investigations and new knowledge to push the terrestrial state of the art (i.e. study of phase diagrams, identification of new system's states, etc). Moreover, the specialized requirements for space medicine have driven advances in terrestrial medical technologies in areas such as monitoring, diagnostic, prevention and treatment. This talk will provide an overview of compelling examples in key areas of interest for terrestrial medical applications.

  16. Space Resource Utilization: Technologies and Potential Synergism with Terrestrial Mining

    Science.gov (United States)

    Sanders, Gerald B.

    2015-01-01

    Space Resources and Their Uses: The idea of using resources in space to support human exploration and settlement or for economic development and profit beyond the surface of Earth has been proposed and discussed for decades. Work on developing a method to extract oxygen from lunar regolith started even before humans set foot on the Moon for the first time. The use of space resources, commonly referred to as In Situ Resource Utilization (ISRU), involves the processes and operations to harness and utilize resources in space (both natural and discarded) to create products for subsequent use. Potential space resources include water, solar wind implanted volatiles (hydrogen, helium, carbon, nitrogen, etc.), vast quantities of metals and minerals in extraterrestrial soils, atmospheric constituents, unlimited solar energy, regions of permanent light and darkness, the vacuum and zero-gravity of space itself, trash and waste from human crew activities, and discarded hardware that has completed its primary purpose. ISRU covers a wide variety of concepts, technical disciplines, technologies, and processes. When considering all aspects of ISRU, there are 5 main areas that are relevant to human space exploration and the commercialization of space: 1. Resource Characterization and Mapping, 2. In Situ Consumables Production, 3. Civil Engineering and Construction, 4. In Situ Energy Production and Storage, and 5. In Situ Manufacturing.

  17. An Artificial-Gravity Space-Settlement Ground-Analogue Design Concept

    Science.gov (United States)

    Dorais, Gregory A.

    2016-01-01

    The design concept of a modular and extensible hypergravity facility is presented. Several benefits of this facility are described including that the facility is suitable as a full-scale artificial-gravity space-settlement ground analogue for humans, animals, and plants for indefinite durations. The design is applicable as an analogue for on-orbit settlements as well as those on moons, asteroids, and Mars. The design creates an extremely long-arm centrifuge using a multi-car hypergravity vehicle travelling on one or more concentric circular tracks. This design supports the simultaneous generation of multiple-gravity levels to explore the feasibility and value of and requirements for such space-settlement designs. The design synergizes a variety of existing technologies including centrifuges, tilting trains, roller coasters, and optionally magnetic levitation. The design can be incrementally implemented such that the facility can be operational for a small fraction of the cost and time required for a full implementation. Brief concept of operation examples are also presented.

  18. Cost-Loss Analysis of Ensemble Solar Wind Forecasting: Space Weather Use of Terrestrial Weather Tools

    Science.gov (United States)

    Henley, E. M.; Pope, E. C. D.

    2017-12-01

    This commentary concerns recent work on solar wind forecasting by Owens and Riley (2017). The approach taken makes effective use of tools commonly used in terrestrial weather—notably, via use of a simple model—generation of an "ensemble" forecast, and application of a "cost-loss" analysis to the resulting probabilistic information, to explore the benefit of this forecast to users with different risk appetites. This commentary aims to highlight these useful techniques to the wider space weather audience and to briefly discuss the general context of application of terrestrial weather approaches to space weather.

  19. Effect of the Ionosphere on Space and Terrestrial Systems

    Science.gov (United States)

    1978-01-01

    of the ionospheric conditions along the path. shown schematically in Figure 1. The energetic par- ticle data were obtained by the Space Sciences Labor ...Adaptive tures, of difficult inclusion in clima - Ionospheric Range Error Correction for tological models. To accommodate then High Accuracy Radars, URSI...that size and a consistent identification in clima - are effervescent from hour to hour. tology, such as the nighttime trough and the plasmapause

  20. Overview of Global Monitoring of Terrestrial Chlorophyll Fluorescence from Space

    Science.gov (United States)

    Guanter, Luis; Zhang, Yongguang; Kohler, Philipp; Walther, Sophia; Frankenberg, Christian; Joiner, Joanna

    2016-01-01

    Despite the critical importance of photosynthesis for the Earth system, understanding how it is influenced by factors such as climate variability, disturbance history, and water or nutrient availability remains a challenge because of the complex interactions and the lack of GPP measurements at various temporal and spatial scales. Space observations of the sun-induced chlorophyll fluorescence (SIF) electromagnetic signal emitted by plants in the 650-850nm spectral range hold the promise of providing a new view of vegetation photosynthesis on a global basis. Global retrievals of SIF from space have recently been achieved from a number of spaceborne spectrometers originally intended for atmospheric research. Despite not having been designed for land applications, such instruments have turned out to provide the necessary spectral and radiometric sensitivity for SIF retrieval from space. The first global measurements of SIF were achieved in 2011 from spectra acquired by the Japanese GOSAT mission launched in 2009. The retrieval takes advantage of the high spectral resolution provided by GOSATs Fourier Transform Spectrometer (FTS) which allows the evaluation of the in-filling of solar Fraunhofer lines by SIF. Unfortunately, GOSAT only provides a sparse spatial sampling with individual soundings separated by several hundred kilometers. Complementary, the Global Ozone Monitoring Experiment-2 (GOME-2) instruments onboard MetOp-A and MetOp-B enable SIF retrievals since 2007 with a continuous and global spatial coverage. GOME-2 measures in the red and near-infrared (NIR) spectral regions with a spectral resolution of 0.5 nm and a pixel size of up to 40x40 km2. Most recently, another global and spatially continuous data set of SIF retrievals at 740 nm spanning the 2003-2012 time frame has been produced from ENVISATSCIAMACHY. This observational scenario has been completed by the first fluorescence data from the NASA-JPL OCO-2 mission (launched in July 2014) and the upcoming

  1. Space Life Support Technology Applications to Terrestrial Environmental Problems

    Science.gov (United States)

    Schwartzkopf, Steven H.; Sleeper, Howard L.

    1993-01-01

    Many of the problems now facing the human race on Earth are, in fact, life support issues. Decline of air Quality as a result of industrial and automotive emissions, pollution of ground water by organic pesticides or solvents, and the disposal of solid wastes are all examples of environmental problems that we must solve to sustain human life. The technologies currently under development to solve the problems of supporting human life for advanced space missions are extraordinarily synergistic with these environmental problems. The development of these technologies (including both physicochemical and bioregenerative types) is increasingly focused on closing the life support loop by removing and recycling contaminants and wastes to produce the materials necessary to sustain human life. By so doing, this technology development effort also focuses automatically on reducing resupply logistics requirements and increasing crew safety through increased self-sufficiency. This paper describes several technologies that have been developed to support human life in space and illustrates the applicability of the technologies to environmental problems including environmental remediation and pollution prevention.

  2. Petroleum potential of Oligocene lacustrine mudstones and coals at Dong Ho, Vietnam — an outcrop analogue to terrestrial source rocks in the greater Song Hong Basin

    Science.gov (United States)

    Petersen, H. I.; Andersen, C.; Anh, P. H.; Bojesen-Koefoed, J. A.; Nielsen, L. H.; Nytoft, H. P.; Rosenberg, P.; Thanh, L.

    2001-02-01

    The outcrop of Oligocene age at Dong Ho, northern Vietnam, may constitute an immature analogue to offshore terrestrial source rocks in the greater Song Hong Basin. The outcrop includes an interval with two source rocks: (1) highly oil-prone carbonaceous mudstones containing kerogen types IIA and IIA/I, and with TOC contents from 6.48 to 16.89 wt%, and HI values from 472 to 690; and (2) oil-prone humic coals (kerogen type III) with HI values from 200 to 242. The mudstones were deposited in oxygen-deficient lakes, which on occasion were subject to marine influence, and the coals accumulated in freshwater peat-forming mires. The coals have broad activation energy ( Ea) distributions, while the mudstones have Ea distributions characterised by a pronounced principal Ea. During artificial maturation about 16-17% of the organic carbon in the coals and 45-50% of the organic carbon in the mudstones participated in petroleum formation. The two source rocks primary generate oil and secondary generate gas, however, the mudstones realised the majority of their potential over a more narrow temperature range than the coals. The excellent generative potential of the terrestrial source rocks at Dong Ho is encouraging for offshore exploration for reservoirs charged by Cenozoic rift-lake successions.

  3. Advances in terrestrial physics research at NASA/Goddard Space Flight Center

    Science.gov (United States)

    Salomonson, Vincent V.

    1987-01-01

    Some past, current, and future terrestrial physics research activities at NASA/Goddard Space Flight Center are described. The uses of satellites and sensors, such as Tiros, Landsat, Nimbus, and SMMR, for terrestrial physics research are discussed. The spaceborne data are applicable for monitoring and studying vegetation, snow, and ice dynamics; geological features; soil moisture; water resources; the geoid of the earth; and the earth's magnetic field. Consideration is given to improvements in remote sensing systems and data records and the Earth Observing System sensor concepts.

  4. Carbon Nanotube Based Chemical Sensors for Space and Terrestrial Applications

    Science.gov (United States)

    Li, Jing; Lu, Yijiang

    2009-01-01

    A nanosensor technology has been developed using nanostructures, such as single walled carbon nanotubes (SWNTs), on a pair of interdigitated electrodes (IDE) processed with a silicon-based microfabrication and micromachining technique. The IDE fingers were fabricated using photolithography and thin film metallization techniques. Both in-situ growth of nanostructure materials and casting of the nanostructure dispersions were used to make chemical sensing devices. These sensors have been exposed to nitrogen dioxide, acetone, benzene, nitrotoluene, chlorine, and ammonia in the concentration range of ppm to ppb at room temperature. The electronic molecular sensing of carbon nanotubes in our sensor platform can be understood by intra- and inter-tube electron modulation in terms of charge transfer mechanisms. As a result of the charge transfer, the conductance of p-type or hole-richer SWNTs in air will change. Due to the large surface area, low surface energy barrier and high thermal and mechanical stability, nanostructured chemical sensors potentially can offer higher sensitivity, lower power consumption and better robustness than the state-of-the-art systems, which make them more attractive for defense and space applications. Combined with MEMS technology, light weight and compact size sensors can be made in wafer scale with low cost. Additionally, a wireless capability of such a sensor chip can be used for networked mobile and fixed-site detection and warning systems for military bases, facilities and battlefield areas.

  5. Can space ties on board GNSS satellites replace terrestrial ties in the implementation of Terrestrial Reference Frames?

    Science.gov (United States)

    Bruni, Sara; Zerbini, Susanna; Altamimi, Zuheir; Rebischung, Paul; Errico, Maddalena; Santi, Efisio

    2016-04-01

    SLR techniques via the so-called space ties, instead of relying on the terrestrial ties evaluated with ground measurement campaigns at co-located ITRF sites.

  6. Mount Everest: a space analogue for speech monitoring of cognitive deficits and stress.

    Science.gov (United States)

    Lieberman, Philip; Morey, Angie; Hochstadt, Jesse; Larson, Mara; Mather, Sandra

    2005-06-01

    In deep-space missions, the basal ganglia and hippocampus, subcortical structures of the brain that play critical roles in motor activity, cognition, and memory, will be vulnerable to damage from cosmic rays. These metabolically active structures are also sensitive to damage arising from the low oxygen content of air at extreme altitudes. We have, therefore, used Mount Everest as an analogue for deep space, where astronauts will be subject to danger and stress as well as neural damage. We can ethically obtain data because our climber-subjects already intend to climb Mt. Everest. We record speech and test cognitive and linguistic performance before, during, and after exposure to hypoxic conditions. From these data we have derived and validated computer-implemented acoustic voice measures that track slight as well as profound cognitive impairment. Vowel duration and speech motor sequencing errors increase as climbers ascend, reflecting degraded basal ganglia activity. These metrics detect deficits in language comprehension and the ability to change plans in changing circumstances. Preliminary analyses also reveal memory deficits reflecting hippocampal damage. Our speech metrics are unobtrusive and do not reveal the content of a verbal message; they could be derived automatically, allowing space crews to detect subtle motor and cognitive deficits and invoke countermeasures before performance is profoundly impaired. In future work we will be validating the voice metrics of stress in collaboration with the Dinges NSBRI laboratory study of task-induced stress. Our procedures can also be applied in general aviation and in the treatment of Parkinson's disease, Alzheimer's dementia, and other neurological disorders.

  7. The requirements and feasibility of business planning in the office of space and terrestrial applications

    Science.gov (United States)

    Greenberg, J. S.; Miller, B. P.

    1979-01-01

    The feasibility of applying strategic business planning techniques which are developed and used in the private sector to the planning of certain projects within the NASA Office of Space and Terrestrial Applications was assessed. The methods of strategic business planning that are currently in use in the private sector are examined. The typical contents of a private sector strategic business plan and the techniques commonly used to develop the contents of the plan are described, along with modifications needed to apply these concepts to public sector projects. The current long-range planning process in the Office of Space and Terrestrial Applications is reviewed and program initiatives that might be candidates for the use of strategic business planning techniques are identified. In order to more fully illustrate the information requirements of a strategic business plan for a NASA program, a sample business plan is prepared for a hypothetical Operational Earth Resources Satellite program.

  8. Isotopic power supplies for space and terrestrial systems: quality assurance by Sandia National Laboratories

    International Nuclear Information System (INIS)

    Hannigan, R.L.; Harnar, R.R.

    1981-09-01

    The Sandia National Laboratories participation in Quality Assurance (QA) programs for Radioisotopic Thermoelectric Generators which have been used in space and terrestrial systems over the past 15 years is summarized. Basic elements of the program are briefly described and recognition of assistance from other Sandia organizations is included. Descriptions of the various systems for which Sandia has had the QA responsibility are also presented. In addition, the outlook for Sandia participation in RTG programs for the next several years is noted

  9. Isotopic power supplies for space and terrestrial systems: quality assurance by Sandia National Laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Hannigan, R.L.; Harnar, R.R.

    1981-09-01

    The Sandia National Laboratories participation in Quality Assurance (QA) programs for Radioisotopic Thermoelectric Generators which have been used in space and terrestrial systems over the past 15 years is summarized. Basic elements of the program are briefly described and recognition of assistance from other Sandia organizations is included. Descriptions of the various systems for which Sandia has had the QA responsibility are also presented. In addition, the outlook for Sandia participation in RTG programs for the next several years is noted.

  10. Anomalous Features on Anomalous Rocks — Deciphering the Physical Weathering History of Iron Meteorites found on Mars using Terrestrial Analogues

    Science.gov (United States)

    Ashley, J.

    2015-12-01

    behavior. For example, flutings appear to be coalesced boreholes in cross section, which can be truncated locally, producing sharp-edged margins in both martian and terrestrial examples. Topographic visualization from meteorite stereo imagery are expected to enable quantitative comparison with analog morphologies.

  11. Space microbiology--lethality, mutagenicity and cytological effects of terrestrial microorganisms by irradiation of cosmic proton under simulated space condition.

    Science.gov (United States)

    Koike, J; Taguchi, H

    1993-04-01

    We have been discussing in connection with a space quarantine. The subject is not merely an academic problem, but it contains a fundamental problem which avoid the contamination of other planets by terrestrial microflora. The space environments in the solar system were simulated by using an apparatus of cryostat (low temperature of 110-310K, high vacuum of 1 x 10(-8) torr) and proton irradiation from the Van de Graaff generator. After exposure to a barrage of protons corresponding to about 250 years in solar space, Tobacco mosaic virus, Bacillus subtilis spore, Staphylococcus aureus. Micrococcusflavus, Clostridium mangenoti spore and Aspergillus niger spore showed considerably high survival rates. Furthermore, it was found firstly that an irradiation of proton induced considerable mutation frequency compared to that of spontaneous and caused also the cytological effects based on a damage of chromosome.

  12. Flight Experience from Space Photovoltaic Concentrator Arrays and its Implication on Terrestrial Concentrator Systems

    Science.gov (United States)

    Piszczor, Michael F., Jr.

    2003-01-01

    Nearly all photovoltaic solar arrays flown in space have used a planar (non- concentrating) design. However, there have been a few notable exceptions where photovoltaic concentrators have been tested and used as the mission s primary power source. Among these are the success experienced by the SCARLET (Solar Concentrator Array with Refractive Linear Element Technology) concept used to power NASA's Deep Space 1 mission and the problems encountered by the original Boeing 702 reflective trough concentrator design. This presentation will give a brief overview of past photovoltaic concentrator systems that have flown in space, specifically addressing the valuable lessons learned from flight experience, and other viable concentrator concepts that are being proposed for the future. The general trends of this flight experience will be noted and discussed with regard to its implications on terrestrial photovoltaic concentrator designs.

  13. Exploring New Multi-Instrument Approaches To Observing Terrestrial Ecosystems And The Carbon Cycle From Space

    Science.gov (United States)

    Pavlick, R.; Schimel, D.; Dubayah, R.; Wennberg, P. O.

    2015-12-01

    In October 2015, we held a five-day workshop at the Keck Institute for Space Studies, bringing together experts on terrestrial ecology and the carbon cycle, remote sensing, in-situ networks, modeling, and systems engineering. The goals of the workshop were to: 1) Identify grand challenges in terrestrial ecology and carbon cycle science and outline how new multi-instrument remote sensing products can enable revolutionary advancements towards unlocking those challenges 2) Collaborate on using existing airborne, space-based, and ground-based measurements to highlight and quantify those potential advancements 3) Explore how multi-instrument data products can reduce key parameter and structural uncertainties in terrestrial biosphere models The more general themes of the workshop were framed around the potential, that in a few years time, we could see co-flight of suite of sensors aboard the International Space Station providing simultaneous observations of ecosystem structure, functioning, and composition. These include two instruments recently selected by the NASA Earth Venture Instrument program, GEDI, a LiDAR which will measure the 3D structure and biomass of forests, and ECOSTRESS, a thermal radiometer, which will estimate evapotranspiration and plant water stress. These also include two proposed instruments, OCO-3, capable of targeted mapping of solar-induced fluorescence and column CO2, and an imaging spectrometer, which would provide near-global maps of plant biodiversity and plant canopy biochemistry. The workshop sought to break down the 'stovepiping', that can arise from the traditionally contingency-adverse systems engineering approach to mission planning, by developing a broader strategy that would combine data products from multiple sensors to address carbon cycle grand challenge questions that no single sensor can address alone. We will present highlights from the workshop, as well as results from the discussion of observation needs, potential data

  14. Textural and Mineralogical Characteristics of Microbial Fossils Associated with Modern and Ancient Iron (Oxyhydr)Oxides: Terrestrial Analogue for Sediments in Gale Crater

    Science.gov (United States)

    Chan, Marjorie A.; McPherson, Brian J.

    2014-01-01

    Abstract Iron (oxyhydr)oxide microbial mats in modern to ∼100 ka tufa terraces are present in a cold spring system along Ten Mile Graben, southeastern Utah, USA. Mats exhibit morphological, chemical, and textural biosignatures and show diagenetic changes that occur over millennial scales. The Jurassic Brushy Basin Member of the Morrison Formation in the Four Corners region of the USA also exhibits comparable microbial fossils and iron (oxyhydr)oxide biosignatures in the lacustrine unit. Both the modern spring system and Brushy Basin Member represent alkaline, saline, groundwater-fed systems and preserve diatoms and other similar algal forms with cellular elaboration. Two distinct suites of elements (1. C, Fe, As and 2. C, S, Se, P) are associated with microbial fossils in modern and ancient iron (oxyhydr)oxides and may be potential markers for biosignatures. The presence of ferrihydrite in ∼100 ka fossil microbial mats and Jurassic rocks suggests that this thermodynamically unstable mineral may also be a potential biomarker. One of the most extensive sedimentary records on Mars is exposed in Gale Crater and consists of non-acidic clays and sulfates possibly of lacustrine origin. These terrestrial iron (oxyhydr)oxide examples are a valuable analogue because of similar iron- and clay-rich host rock compositions and will help (1) understand diagenetic processes in a non-acidic, saline lacustrine environment such as the sedimentary rocks in Gale Crater, (2) document specific biomediated textures, (3) demonstrate how biomediated textures might persist or respond to diagenesis over time, and (4) provide a ground truth library of textures to explore and compare in extraterrestrial iron (oxyhydr)oxides, where future explorations hope to detect past evidence of life. Key Words: Biogeochemistry—Mars—Biosignatures—Diagenesis—Iron oxides. Astrobiology 14, 1–14. PMID:24380534

  15. Textural and mineralogical characteristics of microbial fossils associated with modern and ancient iron (oxyhydr)oxides: terrestrial analogue for sediments in Gale Crater.

    Science.gov (United States)

    Potter-McIntyre, Sally L; Chan, Marjorie A; McPherson, Brian J

    2014-01-01

    Iron (oxyhydr)oxide microbial mats in modern to ∼100 ka tufa terraces are present in a cold spring system along Ten Mile Graben, southeastern Utah, USA. Mats exhibit morphological, chemical, and textural biosignatures and show diagenetic changes that occur over millennial scales. The Jurassic Brushy Basin Member of the Morrison Formation in the Four Corners region of the USA also exhibits comparable microbial fossils and iron (oxyhydr)oxide biosignatures in the lacustrine unit. Both the modern spring system and Brushy Basin Member represent alkaline, saline, groundwater-fed systems and preserve diatoms and other similar algal forms with cellular elaboration. Two distinct suites of elements (1. C, Fe, As and 2. C, S, Se, P) are associated with microbial fossils in modern and ancient iron (oxyhydr)oxides and may be potential markers for biosignatures. The presence of ferrihydrite in ∼100 ka fossil microbial mats and Jurassic rocks suggests that this thermodynamically unstable mineral may also be a potential biomarker. One of the most extensive sedimentary records on Mars is exposed in Gale Crater and consists of non-acidic clays and sulfates possibly of lacustrine origin. These terrestrial iron (oxyhydr)oxide examples are a valuable analogue because of similar iron- and clay-rich host rock compositions and will help (1) understand diagenetic processes in a non-acidic, saline lacustrine environment such as the sedimentary rocks in Gale Crater, (2) document specific biomediated textures, (3) demonstrate how biomediated textures might persist or respond to diagenesis over time, and (4) provide a ground truth library of textures to explore and compare in extraterrestrial iron (oxyhydr)oxides, where future explorations hope to detect past evidence of life.

  16. Design of shipping packages to transport varying radioisotopic source materials for future space and terrestrial missions

    International Nuclear Information System (INIS)

    Barklay, C.D.

    1995-01-01

    The exploration of space will begin with manned missions to the moon and to Mars, first for scientific discoveries, then for mining and manufacturing. Because of the great financial costs of this type of exploration, it can only be accomplished through an international team effort. This unified effort must include the design, planning and, execution phases of future space missions, extending down to such activities as isotope processing, and shipping package design, fabrication, and certification. All aspects of this effort potentially involve the use of radioisotopes in some capacity, and the transportation of these radioisotopes will be impossible without a shipping package that is certified by the Nuclear Regulatory Commission or the U.S. Department of Energy for domestic shipments, and the U.S. Department of Transportation or the International Atomic Energy Agency for international shipments. To remain without the international regulatory constraints, and still support the needs of new and challenging space missions conducted within ever-shrinking budgets, shipping package concepts must be innovative. A shipping package must also be versatile enough to be reconfigured to transport the varying radioisotopic source materials that may be required to support future space and terrestrial missions. One such package is the Mound USA/9516/B(U)F. Taking into consideration the potential need to transport specific types of radioisotopes, approximations of dose rates at specific distances were determined taking into account the attenuation of dose rate with distance for varying radioisotopic source materials. As a result, it has been determined that the shipping package requirements that will be demanded by future space (and terrestrial) missions can be met by making minor modifications to the USA/9516/B(U)F. copyright 1995 American Institute of Physics

  17. Bidirectional reflectance and VIS-NIR spectroscopy of cometary analogues under simulated space conditions

    Science.gov (United States)

    Jost, Bernhard; Pommerol, Antoine; Poch, Olivier; Yoldi, Zuriñe; Fornasier, Sonia; Hasselmann, Pedro Henrique; Feller, Clément; Carrasco, Nathalie; Szopa, Cyril; Thomas, Nicolas

    2017-10-01

    This work is intended to be the second publication in a series of papers reporting on the spectro-photometric properties of cometary analogues measured in the laboratory. Herein, we provide in-situ hyperspectral imaging data in the 0.40-2.35 μm range from three sublimation experiments under simulated space conditions in thermal vacuum from samples made of water ice, carbonaceous compounds and complex organic molecules. The dataset is complemented by measurements of the bidirectional reflectance in the visible (750 nm) spectral range before and after sublimation. A qualitative characterization of surface evolution processes is provided as well as a description of morphological changes during the simulation experiment. The aim of these experiments is to mimic the spectrum of comet 67P/Churyumov-Gerasimenko (67P) as acquired by the Rosetta mission by applying sublimation experiments on the mixtures of water ice with a complex organic material (tholins) and carbonaceous compounds (carbon black; activated charcoal) studied in our companion publication (Jost et al., submitted). Sublimation experiments are needed to develop the particular texture (high porosity), expected on the nucleus' surface, which might have a strong influence on spectro-photometric properties. The spectrally best matching mixtures of non volatile organic molecules from Jost et al. (submitted) are mixed with fine grained water ice particles and evolved in a thermal vacuum chamber, in order to monitor the influence of the sublimation process on their spectro-photometric properties. We demonstrate that the way the water ice and the non-volatile constituents are mixed, plays a major role in the formation and evolution of a surface residue mantle as well as having influence on the consolidation processes of the underlying ice. Additionally it results in different activity patterns under simulated insolation cycles. Further we show that the phase curves of samples having a porous surface mantle layer

  18. The coronas-F space mission key results for solar terrestrial physics

    CERN Document Server

    2014-01-01

    This volume is the updated and extended translation of the Russian original. It presents the results of observations of solar activity and its effects in the Earth space environment carried out from July 2001 to December 2005 on board the CORONAS-F space mission. The general characteristics of the CORONAS-F scientific payload are provided with a description of the principal experiments. The main results focus on the global oscillations of the Sun (p-modes), solar corona, solar flares, solar cosmic rays, Earth’s radiation belts, and upper atmosphere. The book will be welcomed by students, post-graduates, and scientists working in the field of solar and solar-terrestrial physics. This English edition is supplemented by sections presenting new results of the SPIRIT and TESIS experiments under the CORONAS solar program, as well as from the SONG experiment onboard the CORONAS-F satellite.

  19. Self-rewetting carbon nanofluid as working fluid for space and terrestrial heat pipes

    Science.gov (United States)

    Di Paola, R.; Savino, R.; Mirabile Gattia, D.; Marazzi, R.; Vittori Antisari, M.

    2011-11-01

    Thermal management is very important in modern electronic systems. Recent researches have been dedicated to the study of the heat transfer performances of binary heat transfer fluids with peculiar surface tension properties and in particular to that of "self-rewetting fluids", i.e., liquids with a surface tension increasing with temperature and concentration. Since in the course of liquid/vapor-phase change, self-rewetting fluids behavior induces a rather strong liquid inflow (caused by both temperature and concentration gradients) from the cold region (where liquid condensates) to the hot evaporator region, this fluids have been proposed and investigated as new heat transfer fluids for advanced heat transfer devices, e.g., heat pipes or heat spreaders for terrestrial and space applications (Savino et al. in Space Technol 25(1):59-61, 2009). The present work is dedicated to the study of the thermophysical properties of a new class of heat transfer fluids based on water/alcohol solutions with suspended carbon nanostructures, in particular single-wall carbon nanohorns (SWNH), synthesized by a homemade apparatus with an AC arc discharge in open air (Mirabile Gattia et al. in Nanotechnology 18:255604, 2007). SWNHs are cone-shaped nanoparticles with diameters between 1 and 5 nm and lengths in the range of 20-100 nm. SWNHs could be found in the form of quite-spherical aggregates with diameters ranging from 20 to 100 nm. The paper also discusses the results of these investigations and laboratory characterization tests of different heat pipes, including reference ordinary heat pipes and innovative pipes filled with self-rewetting fluids and self-rewetting nanofluids. The potential interest of the proposed studies stems from the large number of possible industrial applications, including space technologies and terrestrial applications, such as cooling of electronic components.

  20. Self-rewetting carbon nanofluid as working fluid for space and terrestrial heat pipes

    International Nuclear Information System (INIS)

    Di Paola, R.; Savino, R.; Mirabile Gattia, D.; Marazzi, R.; Vittori Antisari, M.

    2011-01-01

    Thermal management is very important in modern electronic systems. Recent researches have been dedicated to the study of the heat transfer performances of binary heat transfer fluids with peculiar surface tension properties and in particular to that of “self-rewetting fluids”, i.e., liquids with a surface tension increasing with temperature and concentration. Since in the course of liquid/vapor-phase change, self-rewetting fluids behavior induces a rather strong liquid inflow (caused by both temperature and concentration gradients) from the cold region (where liquid condensates) to the hot evaporator region, this fluids have been proposed and investigated as new heat transfer fluids for advanced heat transfer devices, e.g., heat pipes or heat spreaders for terrestrial and space applications (Savino et al. in Space Technol 25(1):59–61, 2009). The present work is dedicated to the study of the thermophysical properties of a new class of heat transfer fluids based on water/alcohol solutions with suspended carbon nanostructures, in particular single-wall carbon nanohorns (SWNH), synthesized by a homemade apparatus with an AC arc discharge in open air (Mirabile Gattia et al. in Nanotechnology 18:255604, 2007). SWNHs are cone-shaped nanoparticles with diameters between 1 and 5 nm and lengths in the range of 20–100 nm. SWNHs could be found in the form of quite-spherical aggregates with diameters ranging from 20 to 100 nm. The paper also discusses the results of these investigations and laboratory characterization tests of different heat pipes, including reference ordinary heat pipes and innovative pipes filled with self-rewetting fluids and self-rewetting nanofluids. The potential interest of the proposed studies stems from the large number of possible industrial applications, including space technologies and terrestrial applications, such as cooling of electronic components.

  1. Emphasis on High Power Lithium Ion Technology for Pulse-Load Operations: Terrestrial Developments Potential Benefits to Space Application

    Science.gov (United States)

    Fusalba, Florence; Chami, Marianne; Rey, Marlene; Moreau, Gilles; Reynier, Yvan; Azais, Philippe

    2014-08-01

    Currently Li-ion batteries are preferred to supply space missions owing to their large energy density. However, these batteries are designed for standard missions without high-power pulsed payloads, therefore for low C-rates profiles, and do not answer the needs of high- power space applications. More enhanced power sources compatible with extended thermal environment are therefore needed for some space applications like next generation launchers or radar satellites. It is believed that synergy between terrestrial and space sectors could foster the avoidance of multiple financing for the development of similar technologies and systems, as well as dual-use of facilities, providing some real applications for synergy. CEA experienced terrestrial requirements for Hybrid Electric Vehicle applications, start & stop, e-buses and other larger vehicles. In this frame, materials especially designed for high power needs, new cells conception and recently hybrid supercapacitors developments at CEA are discussed as potential solutions for space high power feature.

  2. Lunar Underground Mining and Construction : A Terrestrial Vision enabling Space Exploration and Commerce

    Science.gov (United States)

    Baiden, Greg; Grenier, Louis; Blair, Brad

    As the Space Shuttle, Candarm and Space Station near their useful extended lives before the end of this decade, the question "What will be the next frontier for humans and robots to explore and how will we get there?" needs to be considered. Several countries are planning their next take on the exploration of the solar system. The moon is still a viable destination for several countries for two main reasons: the recent discovery of water improves the prospects of a basic infrastructure capability that would enable future commercial interests to drive the impetus to deploy profitable operations in the near future. The commercial appeal to establish a permanent lunar base should rise in this decade with the prospect of using natural resources available, in particular recently found water. The ability to break water into hydrogen and oxygen for providing the main necessities of life, rocket fuel and air to breathe make this permanent base feasible. Furthermore, several significant environmental issues will force this permanent base underground. These issues include lunar radiation, solar flares, temperature extremes and micro-meteorites. Lunar radiation alone will force this move to rock shielding protection of astronauts as at least 10 metres of rock cover will be required to protect human, animals and plants. As early as 1959 the placecountry-regionUS army considered a permanent underground base on the moon. While the original underground idea has merit space pioneers have strayed from this sensible safe concept. Furthermore, advances in proven telerobotic min-ing technology for terrestrial purposes can provide the opportunity for the commercial interests and perhaps government space programs to consider the concept, design, build and implement an underground lunar habitat and a mining and processing operation from basic infrastructure to commercial deployment of profitable operations. This paper discusses a Canadian concept behind a permanent manned outpost on the

  3. Remote Sensing of Aerosol in the Terrestrial Atmosphere from Space: New Missions

    Science.gov (United States)

    Milinevsky, G.; Yatskiv, Ya.; Degtyaryov, O.; Syniavskyi, I.; Ivanov, Yu.; Bovchaliuk, A.; Mishchenko, M.; Danylevsky, V.; Sosonkin, M.; Bovchaliuk, V.

    2015-01-01

    The distribution and properties of atmospheric aerosols on a global scale are not well known in terms of determination of their effects on climate. This mostly is due to extreme variability of aerosol concentrations, properties, sources, and types. Aerosol climate impact is comparable to the effect of greenhouse gases, but its influence is more difficult to measure, especially with respect to aerosol microphysical properties and the evaluation of anthropogenic aerosol effect. There are many satellite missions studying aerosol distribution in the terrestrial atmosphere, such as MISR/Terra, OMI/Aura, AVHHR, MODIS/Terra and Aqua, CALIOP/CALIPSO. To improve the quality of data and climate models, and to reduce aerosol climate forcing uncertainties, several new missions are planned. The gap in orbital instruments for studying aerosol microphysics has arisen after the Glory mission failed during launch in 2011. In this review paper, we describe several planned aerosol space missions, including the Ukrainian project Aerosol-UA that obtains data using a multi-channel scanning polarimeter and wide-angle polarimetric camera. The project is designed for remote sensing of the aerosol microphysics and cloud properties on a global scale.

  4. Assessment of the possible contribution of space ties on-board GNSS satellites to the terrestrial reference frame

    Science.gov (United States)

    Bruni, Sara; Rebischung, Paul; Zerbini, Susanna; Altamimi, Zuheir; Errico, Maddalena; Santi, Efisio

    2018-04-01

    The realization of the international terrestrial reference frame (ITRF) is currently based on the data provided by four space geodetic techniques. The accuracy of the different technique-dependent materializations of the frame physical parameters (origin and scale) varies according to the nature of the relevant observables and to the impact of technique-specific errors. A reliable computation of the ITRF requires combining the different inputs, so that the strengths of each technique can compensate for the weaknesses of the others. This combination, however, can only be performed providing some additional information which allows tying together the independent technique networks. At present, the links used for that purpose are topometric surveys (local/terrestrial ties) available at ITRF sites hosting instruments of different techniques. In principle, a possible alternative could be offered by spacecrafts accommodating the positioning payloads of multiple geodetic techniques realizing their co-location in orbit (space ties). In this paper, the GNSS-SLR space ties on-board GPS and GLONASS satellites are thoroughly examined in the framework of global reference frame computations. The investigation focuses on the quality of the realized physical frame parameters. According to the achieved results, the space ties on-board GNSS satellites cannot, at present, substitute terrestrial ties in the computation of the ITRF. The study is completed by a series of synthetic simulations investigating the impact that substantial improvements in the volume and quality of SLR observations to GNSS satellites would have on the precision of the GNSS frame parameters.

  5. International Living With a Star (ILWS), a new collaborative space program in Solar, Heliospheric and Solar-Terrestrial Physics

    Science.gov (United States)

    Opgenoorth, H. J.; Guhathakurta, M.; Liu, W.; Kosugi, T.; Zelenyi, L.

    2003-04-01

    International cooperation has long been a vital element in the scientific investigation of solar variability and its impact on Earth and its space environment. Recently a new international cooeperative program in solar terrestrial physics has been established by the major space agencies of the world, called the International Living With a Star (ILWS) program. ILWS is a follow on to the highly successful International Solar Terrestrial Physics (ISTP) program which involved international parterners. ISTP, with its steady flow of discoveries and new knowledge in solar Terrestrial physics, has laid the foundation for the coordinated study of the Sun-Earth sytem as a connected stellar-planetary system, system which is humanity's home. The first step in establishing ILWS was taken in the fall of 2000 when funding was approved for the NASA's Living With a Star (LWS) program whose goal is to develop the scientific understanding necessary to effectively address those aspects of the connected Sun-Earth system that directly affect life and society. The scientific goals of ILWS are defined in a broader sense, aiming to include future solar, heliospheric and solar terrestrial missions of both applied and fundamental scientific focus. The ultimate goal of ILWS wil be to increase our understanding of how solar variability affects the terrestrial and other planetary environments both in the short and long term, and in particular how man and society may be affected by solar variability and its consequences. The mission charter of ILWS is 'to stimulate, strengthen and coordinate space research in order to understand the governing processes of the connected Sun-Earth System as an integrated entity'. More detailed ILWS Objectives are to stimulate and facilitate: - The study of the Sun Earth connected system and the effects which influence life and society - Collaboration among all potential partners in solar-terrestrial space missions - Synergistic coordination of international

  6. Space and Terrestrial Power System Integration Optimization Code BRMAPS for Gas Turbine Space Power Plants With Nuclear Reactor Heat Sources

    Science.gov (United States)

    Juhasz, Albert J.

    2007-01-01

    In view of the difficult times the US and global economies are experiencing today, funds for the development of advanced fission reactors nuclear power systems for space propulsion and planetary surface applications are currently not available. However, according to the Energy Policy Act of 2005 the U.S. needs to invest in developing fission reactor technology for ground based terrestrial power plants. Such plants would make a significant contribution toward drastic reduction of worldwide greenhouse gas emissions and associated global warming. To accomplish this goal the Next Generation Nuclear Plant Project (NGNP) has been established by DOE under the Generation IV Nuclear Systems Initiative. Idaho National Laboratory (INL) was designated as the lead in the development of VHTR (Very High Temperature Reactor) and HTGR (High Temperature Gas Reactor) technology to be integrated with MMW (multi-megawatt) helium gas turbine driven electric power AC generators. However, the advantages of transmitting power in high voltage DC form over large distances are also explored in the seminar lecture series. As an attractive alternate heat source the Liquid Fluoride Reactor (LFR), pioneered at ORNL (Oak Ridge National Laboratory) in the mid 1960's, would offer much higher energy yields than current nuclear plants by using an inherently safe energy conversion scheme based on the Thorium --> U233 fuel cycle and a fission process with a negative temperature coefficient of reactivity. The power plants are to be sized to meet electric power demand during peak periods and also for providing thermal energy for hydrogen (H2) production during "off peak" periods. This approach will both supply electric power by using environmentally clean nuclear heat which does not generate green house gases, and also provide a clean fuel H2 for the future, when, due to increased global demand and the decline in discovering new deposits, our supply of liquid fossil fuels will have been used up. This is

  7. Feasibility study of a small, thorium-based fission power system for space and terrestrial applications

    Science.gov (United States)

    Worrall, Michael Jason

    One of the current challenges facing space exploration is the creation of a power source capable of providing useful energy for the entire duration of a mission. Historically, radioisotope batteries have been used to provide load power, but this conventional system may not be capable of sustaining continuous power for longer duration missions. To remedy this, many forays into nuclear powered spacecraft have been investigated, but no robust system for long-term power generation has been found. In this study, a novel spin on the traditional fission power system that represents a potential optimum solution is presented. By utilizing mature High Temperature Gas Reactor (HTGR) technology in conjunction with the capabilities of the thorium fuel cycle, we have created a light-weight, long-term power source capable of a continuous electric power output of up to 70kW for over 15 years. This system relies upon a combination of fissile, highly-enriched uranium dioxide and fertile thorium carbide Tri-Structural Isotropic (TRISO) fuel particles embedded in a hexagonal beryllium oxide matrix. As the primary fissile material is consumed, the fertile material breeds new fissile material leading to more steady fuel loading over the lifetime of the core. Reactor control is achieved through an innovative approach to the conventional boron carbide neutron absorber by utilizing sections of borated aluminum placed in rotating control drums within the reflector. Borated aluminum allows for much smaller boron concentrations, thus eliminating the potential for 10B(n,alpha)6Li heating issues that are common in boron carbide systems. A wide range of other reactivity control systems are also investigated, such as a radially-split rotating reflector. Lastly, an extension of the design to a terrestrial based system is investigated. In this system, uranium enrichment is dropped to 20 percent in order to meet current regulations, a solid uranium-zirconium hydride fissile driver replaces the

  8. Solar-Terrestrial and Astronomical Research Network (STAR-Network) - A Meaningful Practice of New Cyberinfrastructure on Space Science

    Science.gov (United States)

    Hu, X.; Zou, Z.

    2017-12-01

    For the next decades, comprehensive big data application environment is the dominant direction of cyberinfrastructure development on space science. To make the concept of such BIG cyberinfrastructure (e.g. Digital Space) a reality, these aspects of capability should be focused on and integrated, which includes science data system, digital space engine, big data application (tools and models) and the IT infrastructure. In the past few years, CAS Chinese Space Science Data Center (CSSDC) has made a helpful attempt in this direction. A cloud-enabled virtual research platform on space science, called Solar-Terrestrial and Astronomical Research Network (STAR-Network), has been developed to serve the full lifecycle of space science missions and research activities. It integrated a wide range of disciplinary and interdisciplinary resources, to provide science-problem-oriented data retrieval and query service, collaborative mission demonstration service, mission operation supporting service, space weather computing and Analysis service and other self-help service. This platform is supported by persistent infrastructure, including cloud storage, cloud computing, supercomputing and so on. Different variety of resource are interconnected: the science data can be displayed on the browser by visualization tools, the data analysis tools and physical models can be drived by the applicable science data, the computing results can be saved on the cloud, for example. So far, STAR-Network has served a series of space science mission in China, involving Strategic Pioneer Program on Space Science (this program has invested some space science satellite as DAMPE, HXMT, QUESS, and more satellite will be launched around 2020) and Meridian Space Weather Monitor Project. Scientists have obtained some new findings by using the science data from these missions with STAR-Network's contribution. We are confident that STAR-Network is an exciting practice of new cyberinfrastructure architecture on

  9. Planetary quarantine in the solar system. Survival rates of some terrestrial organisms under simulated space conditions by proton irradiation

    Science.gov (United States)

    Koike, J.; Oshima, T.

    We have been studying the survival rates of some species of terrestrial unicellular and multicellular organism (viruses, bacteria, yeasts, fungi, algae, etc.) under simulated interstellar conditions, in connection with planetary quarantine. The interstellar environment in the solar system has been simulated by low temperature, high vacuum (77 K, 4 × 10 -8 torr), and proton irradiation from a Van de Graaff generator. After exposure to a barrage of protons corresponding to about 250 years of irradiation in solar space, tobacco mosaic virus, Bacillus subtilis spores, Staphylococcus aureus, Micrococcus flavus, Aspergillus niger spores, and Clostridium mangenoti spores showed survival rates of 82, 45, 74, 13, 28, and 25%, respectively.

  10. Inferring terrestrial photosynthetic light use efficiency of temperate ecosystems from space

    Science.gov (United States)

    Thomas Hilker; Nicholas C. Coops; Forest G. Hall; Caroline J. Nichol; Alexei Lyapustin; T. Andrew Black; Michael A. Wulder; Ray Leuning; Alan Barr; David Y. Hollinger; Bill Munger; Compton J. Tucker

    2011-01-01

    Terrestrial ecosystems absorb about 2.8 Gt C yr−1, which is estimated to be about a quarter of the carbon emitted from fossil fuel combustion. However, the uncertainties of this sink are large, on the order of ±40%, with spatial and temporal variations largely unknown. One of the largest factors contributing to the uncertainty is photosynthesis,...

  11. Analogue Gravity

    Directory of Open Access Journals (Sweden)

    Barceló Carlos

    2005-12-01

    Full Text Available Analogue models of (and for gravity have a long and distinguished history dating back to the earliest years of general relativity. In this review article we will discuss the history, aims, results, and future prospects for the various analogue models. We start the discussion by presenting a particularly simple example of an analogue model, before exploring the rich history and complex tapestry of models discussed in the literature. The last decade in particular has seen a remarkable and sustained development of analogue gravity ideas, leading to some hundreds of published articles, a workshop, two books, and this review article. Future prospects for the analogue gravity programme also look promising, both on the experimental front (where technology is rapidly advancing and on the theoretical front (where variants of analogue models can be used as a springboard for radical attacks on the problem of quantum gravity.

  12. Extraterrestrial Hemorrhage Control: Terrestrial Developments in Technique, Technology, and Philosophy with Applicability to Traumatic Hemorrhage in Space

    Science.gov (United States)

    Kirkpatrick, Andrew; Dawson, David; Campbell, Mark; Jones, Jeff; Ball, Chad G.; Hamilton, Douglas R.; Dulchavsky, Scott; McBeth, Paul; Holcomb, John

    2004-01-01

    Managing injury and illness during long duration space flight limits efforts to explore beyond low earths orbit. Traumatic injury may be expected to occur in space and is a frequent cause of preventable deaths, often related to uncontrolled or ongoing hemorrhage (H). Such bleeding causes 40% of terrestrial injury mortality. Current guidelines emphasize early control of H compared to intravenous infusions. Recent advances in surgical and critical care may be applicable to trauma care in space, with appropriate considerations of the extreme logistical and personnel limitations. Methods: Recent developments in technique, resuscitation fluids, hemoglobin (Hb) substitutes, hemostatic agents, interventional angiography, damage control principles, and concepts related to suspended animation were reviewed. Results: H associated with instability frequently requires definitive intervention. Direct pressure should be applied to all compressible bleeding, but novel approaches are required for intracavitary noncompressible bleeding. Intravenous hemostatic agents such as recombinant Factor VII may facilitate hemostasis especially when combined with a controlled hypotension approach. Both open and laparoscopic techniques could be used in weightlessness, but require technical expertise not likely to be available. Specific rehearsed invasive techniques such as laparotomy with packing, or arterial catherterization with with robotic intravascular embolization might be considered . Hemodynamic support, thermal manipulation, or pharmacologic induction of a state of metabolic down regulation for whole body preservation may be appropriate. Hypertonic saline, with or without dextran, may temporize vascular support and decrease reperfusion injury, with less mass than other solutions. Hb substitutes have other theoretical advantages. Conclusions: Terrestrial developments suggest potential novel strategies to control H in space, but will required a coordinated program of evaluation and

  13. Analogue Gravity

    Directory of Open Access Journals (Sweden)

    Carlos Barceló

    2011-05-01

    Full Text Available Analogue gravity is a research programme which investigates analogues of general relativistic gravitational fields within other physical systems, typically but not exclusively condensed matter systems, with the aim of gaining new insights into their corresponding problems. Analogue models of (and for gravity have a long and distinguished history dating back to the earliest years of general relativity. In this review article we will discuss the history, aims, results, and future prospects for the various analogue models. We start the discussion by presenting a particularly simple example of an analogue model, before exploring the rich history and complex tapestry of models discussed in the literature. The last decade in particular has seen a remarkable and sustained development of analogue gravity ideas, leading to some hundreds of published articles, a workshop, two books, and this review article. Future prospects for the analogue gravity programme also look promising, both on the experimental front (where technology is rapidly advancing and on the theoretical front (where variants of analogue models can be used as a springboard for radical attacks on the problem of quantum gravity.

  14. The European Space Analogue Rock Collection (ESAR) at the OSUC-Orleans for in situ planetary missions

    Science.gov (United States)

    Westall, F.; Pullan, D.; Bost, N.; Ramboz, C.; Foucher, F.; Hofmann, B.; Bridges, J.

    2011-10-01

    The ESAR is a collection of well-characterised planetary analogue rocks and minerals that can be used for testing in situ instrumentation for planetary exploration. An online database of all relevant structural, compositional and geotechnics information is also available to the instrument teams and to aid data interpretation during missions.

  15. The Pulsed Fission-Fusion (PUFF) Concept for Deep Space Exploration and Terrestrial Power Generation

    Science.gov (United States)

    Adams, Robert; Cassibry, Jason; Schillo, Kevin

    2017-01-01

    This team is exploring a modified Z-pinch geometry as a propulsion system, imploding a liner of liquid lithium onto a pellet containing both fission and fusion fuel. The plasma resulting from the fission and fusion burn expands against a magnetic nozzle, for propulsion, or a magnetic confinement system, for terrestrial power generation. There is considerable synergy in the concept; the lithium acts as a temporary virtual cathode, and adds reaction mass for propulsion. Further, the lithium acts as a radiation shield against generated neutrons and gamma rays. Finally, the density profile of the column can be tailored using the lithium sheath. Recent theoretical and experimental developments (e.g. tailored density profile in the fuel injection, shear stabilization, and magnetic shear stabilization) have had great success in mitigating instabilities that have plagued previous fusion efforts. This paper will review the work in evaluating the pellet sizes and z-pinch conditions for optimal PuFF propulsion. Trades of pellet size and composition with z-pinch power levels and conditions for the tamper and lithium implosion are evaluated. Current models, both theoretical and computational, show that a z-pinch can ignite a small (1 cm radius) fission-fusion target with significant yield. Comparison is made between pure fission and boosted fission targets. Performance is shown for crewed spacecraft for high speed Mars round trip missions and near interstellar robotic missions. The PuFF concept also offers a solution for terrestrial power production. PuFF can, with recycling of the effluent, achieve near 100% burnup of fission fuel, providing a very attractive power source with minimal waste. The small size of PuFF relative to today's plants enables a more distributed power network and less exposure to natural or man-made disruptions.

  16. Airbursts as a viable source of seismic and acoustic energy for the 2016 InSight geophysical lander mission to Mars: analysis using terrestrial analogues

    Science.gov (United States)

    Taylor, Jennifer; Wookey, James; Teanby, Nick

    2014-05-01

    The explosion of a bolide as a terminal airburst, before impact into a planetary surface, is a well-documented source of both seismic and acoustic energy[1]. Here we aim to define some diagnostic properties of a recorded airburst time-series and determine detectability criteria for such events for a single station seismo-acoustic station on the Martian surface. In 2016 NASA will launch the InSight geophysical monitoring system. This lander will carry in its SEIS payload two 3-component seismic instruments - the Short Period (SP) and Very Broadband (VBB) seismometers, as well as a micro-barometer for measurement of atmospheric pressure fluctuations. The SEIS and MB packages aboard InSight could potentially be used together for seismo-acoustic detection of impact or airburst events. In past studies, this technique has been used to analyse and model the Washington State Bolide[2] and, more recently, the Chelyabinsk fireball in 2013[3]. Using a multi-station array, it is possible to estimate total kinetic energy of a bolide, its line-of-sight direction and the approximate time of its terminal burst[4]. However, with only a single station, as would be the case on Mars, more creative methods must be employed to extract information from the event. We explore the diagnostic waveform properties of an airburst, including various arrivals from the event. We also show how dominant frequency changes with distance from the event, altitude and yield. Several terrestrial events are analysed, including the 2013 Chelyabinsk fireball. We present theoretical calculations of the likely proportion of bolide terminal bursts on Mars relative to impacts, based on differences in the structure and composition of the Martian atmosphere. We go on to predict the seismic arrivals that may be observed by InSight from the coupling of the acoustic blast into the Martian crust. It is hoped that these diagnostic tools will be useful to identify and quantify bolide terminal bursts on Mars over the

  17. Terrestrial Plume Impingement Testbed Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Masten Space Systems proposes to create a terrestrial plume impingement testbed for generating novel datasets for extraterrestrial robotic missions. This testbed...

  18. Combination of terrestrial reference frames based on space geodetic techniques in SHAO: methodology and main issues

    Science.gov (United States)

    He, Bing; Wang, Xiao-Ya; Hu, Xiao-Gong; Zhao, Qun-He

    2017-09-01

    Based on years of input from the four geodetic techniques (SLR, GPS, VLBI and DORIS), the strategies of the combination were studied in SHAO to generate a new global terrestrial reference frame as the material realization of the ITRS defined in IERS Conventions. The main input includes the time series of weekly solutions (or fortnightly for SLR 1983-1993) of observational data for satellite techniques and session-wise normal equations for VLBI. The set of estimated unknowns includes 3-dimensional Cartesian coordinates at the reference epoch 2005.0 of the stations distributed globally and their rates as well as the time series of consistent Earth Orientation Parameters (EOPs) at the same epochs as the input. Besides the final solution, namely SOL-2, generated by using all the inputs before 2015.0 obtained from short-term observation processing, another reference solution, namely SOL-1, was also computed by using the input before 2009.0 based on the same combination of procedures for the purpose of comparison with ITRF2008 and DTRF2008 and for evaluating the effect of the latest six more years of data on the combined results. The estimated accuracy of the x-component and y-component of the SOL-1 TRF-origin was better than 0.1 mm at epoch 2005.0 and better than 0.3 mm yr-1 in time evolution, either compared with ITRF2008 or DTRF2008. However, the z-component of the translation parameters from SOL-1 to ITRF2008 and DTRF2008 were 3.4 mm and -1.0 mm, respectively. It seems that the z-component of the SOL-1 TRF-origin was much closer to the one in DTRF2008 than the one in ITRF2008. The translation parameters from SOL-2 to ITRF2014 were 2.2, -1.8 and 0.9 mm in the x-, y- and z-components respectively with rates smaller than 0.4 mm yr-1. Similarly, the scale factor transformed from SOL-1 to DTRF2008 was much smaller than that to ITRF2008. The scale parameter from SOL-2 to ITRF2014 was -0.31 ppb with a rate lower than 0.01 ppb yr-1. The external precision (WRMS) compared

  19. Validation of EM Signals Associated with Major Earthquakes by Joint Analysis of Space and Terrestrial Data

    Science.gov (United States)

    Ouzounov, D.; Pulinets, S.; Parrot, M.; Liu, J. Y.; Hattori, K.; Habib, S.; Taylor, P.; Kafatos, M.

    2009-04-01

    Ground and space observations have shown that there were precursory electromagnetic signals associated with several recent earthquakes. The goals of this work are: (1) to identify the common methodology for statistical validation of the major EQ precursory phenomena; and (2) to cross-examine these results of precursory detection for several major earthquakes by using different methodologies. Our approach is based on data fusion of satellite thermal infrared observations from Aqua, GOES, POES and space plasma parameters variations from DEMETER, simultaneously with ground based multi parameter continuous measurements of GPS/TEC, ion concentration, atmospheric electrical field and magnetic array. We used existing satellite sensors and ground observations and linked them together with the Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) model. This model describes a physical coupling between the boundary layer of atmosphere and the ionosphere with the observed ground and space data prior to some major earthquakes. The significance of joint satellite and ground based EM precursors search was defined by cross validating with different techniques the precursory phenomena around the time of four more recent major earthquakes: (1) M 9.3 Sumatra (Indonesia) 2004.12.26; (2) M7.0 Ping Tong (Taiwan) 2006.12.24; (3) M6.8 Chuetsu Oki (Japan) 2007.7.16; and (4) M7.9 Wenchuan (China) 2008.5.12. Our first results show that simultaneous satellite and ground measurements, using the integrated web, can help to understand better the pre-earthquake processes and provides opportunity for global scale monitoring framework by combining multiple sensor sources.

  20. Analysis of Rain Effects on Terrestrial Free Space Optics based on Data Measured in Tropical Climate

    Directory of Open Access Journals (Sweden)

    Suriza Ahmad Zabidi

    2012-01-01

    Full Text Available Free Space Optics (FSO shows a great alternative as the solution for last mile problem where fiber optics is unavailable due to deployment time and cost constraint.  However, the feasibility of using FSO system as communication link very much depends on local weather.  Since tropical region experiences heavy rainfall, rain with high intensity is expected to affect the FSO link severely. Few prediction models have been proposed by ITU-R based on France and Japan’s measurement. This paper has compared  rain attenuation predicted by  models and  data measured in Malaysia over Free Space Optical links for one year period. Prediction models are clearly unable to predict attenuation measured in tropical climate. ABSTRAK: Wayarles optik menjadi alternatif sebagai satu penyelesaian kepada masalah kesesakan terutama diakhir sesuatu talian dimana ianya tidak dapat diselesaikan dengan menggunakan gentian fiber akibat daripada kekangan masa pemasangan dan masalah kewangan.  Walaubagaimanapun, kejayaan untuk menggunakan wayarless optic ini amat bergantung kepada keadaan cuaca di sesuatu tempat.  Di rantau tropika  hujan lebat sentiasa dialami, oleh itu hujan dengan kepadatan tinggi adalah dijangkakan lebih memberi kesan kepada talian wayarles optic ini. Beberapa model yang telah dicadangkan oleh ITU-R berlandaskan kepada pengumpulan data yang dibuat di Perancis dan Jepun.  Kertas kajian ini akan membandingkan antara model-model yang telah digunapakai dengan data yang dikumpulkan di Malaysia selama setahun.  Jelasnya model yang telah digunapakai tidak dapat digunakan secara berkesan di rantau tropika.KEYWORDS: free space optics; rainfall rate; rain attenuation

  1. A space-based public service platform for terrestrial rescue operations

    Science.gov (United States)

    Fleisig, R.; Bernstein, J.; Cramblit, D. C.

    1977-01-01

    The space-based Public Service Platform (PSP) is a multibeam, high-gain communications relay satellite that can provide a variety of functions for a large number of people on earth equipped with extremely small, very low cost transceivers. This paper describes the PSP concept, the rationale used to derive the concept, the criteria for selecting specific communication functions to be performed, and the advantages of performing such functions via satellite. The discussion focuses on the benefits of using a PSP for natural disaster warning; control of attendant rescue/assistance operations; and rescue of people in downed aircraft, aboard sinking ships, lost or injured on land.

  2. BALANOL ANALOGUES

    DEFF Research Database (Denmark)

    1997-01-01

    The present invention relates to a solid phase methodology for the preparation of a combinatorial library of structural analogues of the natural product balanol (ophiocordin, azepinostatin), which is a protein kinase C (PKC) and protein kinase A (PKA) inhibitor. The method comprises solid...

  3. Use of nuclear space technology of direct energy conversion for terrestrial application

    International Nuclear Information System (INIS)

    Chitaykin, V.I.; Meleta, Ye.A.; Yarygin, V.I.; Mikheyev, A.S.; Tulin, S.M.

    2000-01-01

    In due time the SSC RF-IPPE exercised the scientific supervision and directly participated in the development, fabrication, space flight test and maintenance of the direct energy conversion nuclear power plants (NPP) for space application under the 'BUK' and 'TOPAZ' programs. We have used the acquired experience and the high technologies developed for the 'BUK' NPP with a thermoelectric conversion of thermal (nuclear) energy into electrical one in the development under the order of RAO 'GAZPROM' of the natural gas fired self contained thermoelectric current sources (AIT-500) and heat and electricity sources (TEP-500). These are intended for electrochemical rust protection of gas pipelines and for the electricity and heat supply to the telemetric and microwave-link systems located along the gas pipelines. Of special interest at the moment are the new developments of self contained current sources with the electrical output of ∼500 Wel for new gas pipelines being constructed under the projects such as the 'Yamal-Europe' project. The electrochemical rust protection of gas pipelines laying on unsettled and non-electrified territory of arctic regions of Russia is performed by means of the so-called Cathodic Protection Stations (CPS). Accounting for a complex of rather rigid requirements imposed by arctic operating conditions, the most attractive sources of electricity supply to the CPS are the thermoelectric heat-into-electricity converters and the generators (TEG). This paper deals with the essential results of the development, investigation and testing of unconventional TEGs using the low-temperature bismuth-tellurium thermoelectric batteries assembled together as tubular thermoelectric batteries with a radial ring geometry built into the gas-heated thermoelectric modules, which are collected to make up either the thermoelectric plants for heat and electricity supply or the self contained power sources. One of the peculiarities of these plants is the combination of

  4. Analysis of fog effects on terrestrial Free Space optical communication links

    KAUST Repository

    Esmail, Maged Abdullah

    2016-07-26

    In this paper, we consider and examine fog measurement data, coming from several locations in Europe and USA, and attempt to derive a unified model for fog attenuation in free space optics (FSO) communication links. We evaluate and compare the performance of our proposed model to that of many well-known alternative models. We found that our proposed model, achieves an average RMSE that outperforms them by more than 9 dB. Furthermore, we have studied the performance of the FSO system using different performance metrics such as signal-to-noise (SNR) ratio, bit error rate (BER), and channel capacity. Our results show that FSO is a short range technology. Therefore, FSO is expected to find its place in future networks that will have small cell size, i.e., <1 km diameter. Moreover, our investigation shows that under dense fog, it is difficult to maintain a communications link because of the high signal attenuation, which requires switching the communications to RF backup. Our results show that increasing the transmitted power will improve the system performance under light fog. However, under heavy fog, the effect is minor. To enhance the system performance under low visibility range, multi-hop link is used which can enhance the power budget by using short segments links. Using 22 dBm transmitted power, we obtained BER=10-3 over 1 km link length with 600 m visibility range which corresponds to light fog. However, under lower visibility range equals 40 m that corresponds to dense fog, we obtained the same BER but over 200 m link length. © 2016 IEEE.

  5. Cosmogenic radionuclides. Theory and applications in the terrestrial and space environments

    Energy Technology Data Exchange (ETDEWEB)

    Beer, Juerg [Eidgenoessische Anstalt fuer Wasserversorgung, Abwasserreinigung und Gewaesserschutz, Duebendorf (Switzerland); Steiger, Rudolf von [International Space Science Insitute, Bern (Switzerland); McCracken, Ken [Maryland Univ., College Park (United States). IPST

    2012-07-01

    Cosmogenic radionuclides are radioactive isotopes which are produced by natural processes and distributed within the Earth system. With a holistic view of the environment the authors show in this book how cosmogenic radionuclides can be used to trace and to reconstruct the history of a large variety of processes. They discuss the way in which cosmogenic radionuclides can assist in the quantification of complex processes in the present-day environment. The book aims to demonstrate to the reader the strength of analytic tools based on cosmogenic radionuclides, their contribution to almost any field of modern science, and how these tools may assist in the solution of many present and future problems that we face here on Earth. The book provides a comprehensive discussion of the basic principles behind the applications of cosmogenic (and other) radionuclides as environmental tracers and dating tools. The second section of the book discusses in some detail the production of radionuclides by cosmic radiation, their transport and distribution in the atmosphere and the hydrosphere, their storage in natural archives, and how they are measured. The third section of the book presents a number of examples selected to illustrate typical tracer and dating applications in a number of different spheres (atmosphere, hydrosphere, geosphere, biosphere, solar physics and astronomy). At the same time the authors have outlined the limitations of the use of cosmogenic radionuclides. Written on a level understandable by graduate students without specialist skills in physics or mathematics, the book addresses a wide audience, ranging from archaeology, biophysics, and geophysics, to atmospheric physics, hydrology, astrophysics and space science.

  6. Recent developments and future directions in the monitoring of terrestrial sun-induced chlorophyll fluorescence from space

    Science.gov (United States)

    Guanter, L.

    2017-12-01

    Sun-induced chlorophyll fluorescence (SIF) is an electromagnetic signal emitted by the chlorophyll-a of assimilating plants in the 650-850 nm spectral range. The SIF emission has a mechanistic link to photosynthesis and responds instantaneously to perturbations in environmental conditions such as light and water stress, which makes it a powerful proxy for plants' photosynthetic activity. Global measurements of SIF from space have been available since late 2011 from four different atmospheric satellite missions (chronologically, GOSAT, SCIAMACHY, GOME-2 and OCO-2). The potential of the derived SIF data sets to represent the photosynthetic activity of different ecosystems, including large crop belts worldwide, the Amazon rainforest and boreal evergreen forests has been demonstrated in the relatively short life-time of global SIF data. Despite the demonstrated potential of SIF data as a proxy for global terrestrial gross primary production, current observations are partly hampered by a coarse spatial resolution or the lack of spatial coverage. For this reason, great expectations are put on the upcoming TROPOMI instrument onboard the Copernicus' Sentinel 5-Precursor mission to be launched by mid-end of 2017. TROPOMI will provide daily global coverage with a spatial resolution between 3 and 7 km and continuous spectral coverage of the visible and near-infrared part of the spectrum. The recent selection of FLEX as the ESA Earth Explorer 8 to be launched around 2022 and several upcoming geostationary missions (TEMPO, Sentinel-4 and GeoCARB, covering Europe and the Americas) with potential for SIF retrievals complete an exciting near-future scenario for the monitoring of SIF from space. In this contribution, we will provide an overview of recent developments in the global monitoring of SIF and will introduce the near-future observational scenario with especial emphasis on TROPOMI and the geostationary missions to be launched in the coming years.

  7. Ion-Specific Nutrient Management in Closed Systems: The Necessity for Ion-Selective Sensors in Terrestrial and Space-Based Agriculture and Water Management Systems

    OpenAIRE

    Alain Berinstain; Alan Scott; Matthew Bamsey; Michael Dixon; Cody Thompson; Thomas Graham

    2012-01-01

    The ability to monitor and control plant nutrient ions in fertigation solutions, on an ion-specific basis, is critical to the future of controlled environment agriculture crop production, be it in traditional terrestrial settings (e.g., greenhouse crop production) or as a component of bioregenerative life support systems for long duration space exploration. Several technologies are currently available that can provide the required measurement of ion-specific activities in solution. The greenh...

  8. Solar-Terrestrial Interactions

    National Research Council Canada - National Science Library

    Kahler, Stephen W

    2008-01-01

    This report covers a basic research (6.1 level) task on solar-terrestrial interactions carried out in the Space Weather Center of Excellence over an 11-year period for the Air Force Office of Scientific Research...

  9. Starting a European Space Agency Sample Analogue Collection (ESA2C) and Curation Facility for Exploration Missions.

    Science.gov (United States)

    Smith, C. L.; Rumsey, M. S.; Manick, K.; Gill, S.-J.; Mavris, C.; Schroeven-Deceuninck, H.; Duvet, L.

    2017-09-01

    The ESA2C will support current and future technology development activities that are required for human and robotic exploration of Mars, Phobos, Deimos, C-Type Asteroids and the Moon.The long-term goal of this work is to produce a useful, useable and sustainable resource for engineers and scientists developing technologies for ESA space exploration missions.

  10. Lessons Learned from Biosphere 2: When Viewed as a Ground Simulation/Analogue for Long Duration Human Space Exploration and Settlement

    Science.gov (United States)

    MacCallum, T.; Poynter, J.; Bearden, D.

    A human mission to Mars, or a base on the Moon or Mars, is a longer and more complex mission than any space endeavor undertaken to date. Ground simulations provide a relevant, analogous environment for testing technologies and learning how to manage complex, long duration missions, while addressing inherent mission risks. Multiphase human missions and settlements that may preclude a rapid return to Earth, require high fidelity, end-to-end, at least full mission duration tests in order to evaluate a system's ability to sustain the crew for the entire mission and return the crew safely to Earth. Moreover, abort scenarios are essentially precluded in many mission scenarios, though certain risks may only become evident late in the mission. Aging and compounding effects cannot be simulated through accelerated tests for all aspects of the mission. Until such high fidelity long duration simulations are available, and in order to help prepare those simulations and mission designs, it is important to extract as many lessons as possible from analogous environments. Possibly the best analogue for a long duration space mission is the two year mission of Biosphere 2. Biosphere 2 is a three-acre materially closed ecological system that supported eight crewmembers with food, air and water in a sunlight driven bioregenerative system for two years. It was designed for research applicable to environmental management on Earth and the development of human life support for space. A brief overview of the two-year Biosphere 2 mission is presented, followed by select data and lessons learned that are applicable to the design and operation of a long duration human space mission, settlement or test bed. These lessons include technical, programmatic, and psychological issues

  11. Quantum analogue computing.

    Science.gov (United States)

    Kendon, Vivien M; Nemoto, Kae; Munro, William J

    2010-08-13

    We briefly review what a quantum computer is, what it promises to do for us and why it is so hard to build one. Among the first applications anticipated to bear fruit is the quantum simulation of quantum systems. While most quantum computation is an extension of classical digital computation, quantum simulation differs fundamentally in how the data are encoded in the quantum computer. To perform a quantum simulation, the Hilbert space of the system to be simulated is mapped directly onto the Hilbert space of the (logical) qubits in the quantum computer. This type of direct correspondence is how data are encoded in a classical analogue computer. There is no binary encoding, and increasing precision becomes exponentially costly: an extra bit of precision doubles the size of the computer. This has important consequences for both the precision and error-correction requirements of quantum simulation, and significant open questions remain about its practicality. It also means that the quantum version of analogue computers, continuous-variable quantum computers, becomes an equally efficient architecture for quantum simulation. Lessons from past use of classical analogue computers can help us to build better quantum simulators in future.

  12. Modular Extended-Stay HyperGravity Facility Design Concept: An Artificial-Gravity Space-Settlement Ground Analogue

    Science.gov (United States)

    Dorais, Gregory A.

    2015-01-01

    This document defines the design concept for a ground-based, extended-stay hypergravity facility as a precursor for space-based artificial-gravity facilities that extend the permanent presence of both human and non-human life beyond Earth in artificial-gravity settlements. Since the Earth's current human population is stressing the environment and the resources off-Earth are relatively unlimited, by as soon as 2040 more than one thousand people could be living in Earthorbiting artificial-gravity habitats. Eventually, the majority of humanity may live in artificialgravity habitats throughout this solar system as well as others, but little is known about the longterm (multi-generational) effects of artificial-gravity habitats on people, animals, and plants. In order to extend life permanently beyond Earth, it would be useful to create an orbiting space facility that generates 1g as well as other gravity levels to rigorously address the numerous challenges of such an endeavor. Before doing so, developing a ground-based artificial-gravity facility is a reasonable next step. Just as the International Space Station is a microgravity research facility, at a small fraction of the cost and risk a ground-based artificial-gravity facility can begin to address a wide-variety of the artificial-gravity life-science questions and engineering challenges requiring long-term research to enable people, animals, and plants to live off-Earth indefinitely.

  13. Observing terrestrial water storage and land-atmosphere dynamics from space: Implications for forecasting and climate projections

    Science.gov (United States)

    Seneviratne, S. I.; Humphrey, V.; Nicolai-Shaw, N.; Gudmundsson, L.; Guillod, B.; Hirschi, M.; Michel, D.; Orth, R.; Zscheischler, J.

    2016-12-01

    In recent years, several new satellite products have been derived which allow an unprecendented assessment of terrestrial water storage and land-atmosphere dynamics. This presentation will review some of these new developments, with a focus on drought dynamics, plant-water interactions, and soil moisture-atmosphere feedbacks. Results derived based on the Gravity Recovery and Climate Experiment (GRACE, Humphrey et al. 2016) and the European Space Agency Climate Change Initiative (ESA CCI) Soil Moisture dataset (Nicolai-Shaw et al. 2015, 2016; Hirschi et al. 2014) will be highlighted, as well as assessments using satellite-based estimates of evapotranspiration (Mueller and Seneviratne 2014, Michel et al. 2016), vegetation activity (Zscheischler et al. 2015), and combined soil moisture and precipitation analyses (Guillod et al. 2015). These findings provide new insights on the development of prediction capabilities for droughts, precipitation events, and heat waves, and the reduction of uncertainties in climate model projections. References: Guillod, B.P., B. Orlowsky, D.G. Miralles, A.J. Teuling, and S.I. Seneviratne, 2015. Nature Communications, 6:6443, DOI: 10.1038/ncomms7443 Hirschi, M., B. Mueller, W. Dorigo, and S.I. Seneviratne, 2014. Remote Sensing of Environment, 154, 246-252. Humphrey, V., L. Gudmundsson, and S.I. Seneviratne, 2016. Surv. Geophysics, 37, 357-395, DOI 10.1007/s10712-016-9367-1. Michel, D., et al. 2016. Hydrol. Earth Syst. Sci. 20, 803-822, doi:10.5194/hess-20-803-2016. Mueller, M., and S.I. Seneviratne, 2014. Geophys. Res. Lett., 41, 1-7, doi:10.1002/2013GL058055. Nicolai-Shaw, N., L. Gudmundsson, M. Hirschi, and S.I. Seneviratne, 2016. Geophys. Res. Lett., in review. Nicolai-Shaw, N., M. Hirschi, H. Mittelbach, and S.I. Seneviratne, 2015. Journal of Geophysical Research, 120, doi:10.1002/2015JD023305. Zscheischler, J., R. Orth, and S.I. Seneviratne, 2015. Geophys. Res. Lett., 42, 9816-9824, doi:10.1002/2015GL066563.

  14. Intubation after rapid sequence induction performed by non-medical personnel during space exploration missions: a simulation pilot study in a Mars analogue environment.

    Science.gov (United States)

    Komorowski, Matthieu; Fleming, Sarah

    2015-01-01

    The question of the safety of anaesthetic procedures performed by non anaesthetists or even by non physicians has long been debated. We explore here this question in the hypothetical context of an exploration mission to Mars. During future interplanetary space missions, the risk of medical conditions requiring surgery and anaesthetic techniques will be significant. On Earth, anaesthesia is generally performed by well accustomed personnel. During exploration missions, onboard medical expertise might be lacking, or the crew doctor could become ill or injured. Telemedical assistance will not be available. In these conditions and as a last resort, personnel with limited medical training may have to perform lifesaving procedures, which could include anaesthesia and surgery. The objective of this pilot study was to test the ability for unassisted personnel with no medical training to perform oro-tracheal intubation after a rapid sequence induction on a simulated deconditioned astronaut in a Mars analogue environment. The experiment made use of a hybrid simulation model, in which the injured astronaut was represented by a torso manikin, whose vital signs and hemodynamic status were emulated using a patient simulator software. Only assisted by an interactive computer tool (PowerPoint(®) presentation), five participants with no previous medical training completed a simplified induction of general anaesthesia with intubation. No major complication occurred during the simulated trials, namely no cardiac arrest, no hypoxia, no cardiovascular collapse and no failure to intubate. The study design was able to reproduce many of the constraints of a space exploration mission. Unassisted personnel with minimal medical training and familiarization with the equipment may be able to perform advanced medical care in a safe and efficient manner. Further studies integrating this protocol into a complete anaesthetic and surgical scenario will provide valuable input in designing health

  15. Using the Moon as a high-fidelity analogue environment to study biological and behavioral effects of long-duration space exploration

    Science.gov (United States)

    Goswami, Nandu; Roma, Peter G.; De Boever, Patrick; Clément, Gilles; Hargens, Alan R.; Loeppky, Jack A.; Evans, Joyce M.; Peter Stein, T.; Blaber, Andrew P.; Van Loon, Jack J. W. A.; Mano, Tadaaki; Iwase, Satoshi; Reitz, Guenther; Hinghofer-Szalkay, Helmut G.

    2012-12-01

    Due to its proximity to Earth, the Moon is a promising candidate for the location of an extra-terrestrial human colony. In addition to being a high-fidelity platform for research on reduced gravity, radiation risk, and circadian disruption, the Moon qualifies as an isolated, confined, and extreme (ICE) environment suitable as an analog for studying the psychosocial effects of long-duration human space exploration missions and understanding these processes. In contrast, the various Antarctic research outposts such as Concordia and McMurdo serve as valuable platforms for studying biobehavioral adaptations to ICE environments, but are still Earth-bound, and thus lack the low-gravity and radiation risks of space. The International Space Station (ISS), itself now considered an analog environment for long-duration missions, better approximates the habitable infrastructure limitations of a lunar colony than most Antarctic settlements in an altered gravity setting. However, the ISS is still protected against cosmic radiation by the Earth magnetic field, which prevents high exposures due to solar particle events and reduces exposures to galactic cosmic radiation. On Moon the ICE environments are strengthened, radiations of all energies are present capable of inducing performance degradation, as well as reduced gravity and lunar dust. The interaction of reduced gravity, radiation exposure, and ICE conditions may affect biology and behavior - and ultimately mission success - in ways the scientific and operational communities have yet to appreciate, therefore a long-term or permanent human presence on the Moon would ultimately provide invaluable high-fidelity opportunities for integrated multidisciplinary research and for preparations of a manned mission to Mars.

  16. Ion-Specific Nutrient Management in Closed Systems: The Necessity for Ion-Selective Sensors in Terrestrial and Space-Based Agriculture and Water Management Systems

    Directory of Open Access Journals (Sweden)

    Alain Berinstain

    2012-10-01

    Full Text Available The ability to monitor and control plant nutrient ions in fertigation solutions, on an ion-specific basis, is critical to the future of controlled environment agriculture crop production, be it in traditional terrestrial settings (e.g., greenhouse crop production or as a component of bioregenerative life support systems for long duration space exploration. Several technologies are currently available that can provide the required measurement of ion-specific activities in solution. The greenhouse sector has invested in research examining the potential of a number of these technologies to meet the industry’s demanding requirements, and although no ideal solution yet exists for on-line measurement, growers do utilize technologies such as high-performance liquid chromatography to provide off-line measurements. An analogous situation exists on the International Space Station where, technological solutions are sought, but currently on-orbit water quality monitoring is considerably restricted. This paper examines the specific advantages that on-line ion-selective sensors could provide to plant production systems both terrestrially and when utilized in space-based biological life support systems and how similar technologies could be applied to nominal on-orbit water quality monitoring. A historical development and technical review of the various ion-selective monitoring technologies is provided.

  17. Ion-specific nutrient management in closed systems: the necessity for ion-selective sensors in terrestrial and space-based agriculture and water management systems.

    Science.gov (United States)

    Bamsey, Matthew; Graham, Thomas; Thompson, Cody; Berinstain, Alain; Scott, Alan; Dixon, Michael

    2012-10-01

    The ability to monitor and control plant nutrient ions in fertigation solutions, on an ion-specific basis, is critical to the future of controlled environment agriculture crop production, be it in traditional terrestrial settings (e.g., greenhouse crop production) or as a component of bioregenerative life support systems for long duration space exploration. Several technologies are currently available that can provide the required measurement of ion-specific activities in solution. The greenhouse sector has invested in research examining the potential of a number of these technologies to meet the industry's demanding requirements, and although no ideal solution yet exists for on-line measurement, growers do utilize technologies such as high-performance liquid chromatography to provide off-line measurements. An analogous situation exists on the International Space Station where, technological solutions are sought, but currently on-orbit water quality monitoring is considerably restricted. This paper examines the specific advantages that on-line ion-selective sensors could provide to plant production systems both terrestrially and when utilized in space-based biological life support systems and how similar technologies could be applied to nominal on-orbit water quality monitoring. A historical development and technical review of the various ion-selective monitoring technologies is provided.

  18. Recent Advances in Atmospheric, Solar-Terrestrial Physics and Space Weather From a North-South network of scientists [2006-2016] PART B : Results and Capacity Building

    Science.gov (United States)

    Amory-Mazaudier, C.; Fleury, R.; Petitdidier, M.; Soula, S.; Masson, F.; Davila, J.; Doherty, P.; Elias, A.; Gadimova, S.; Makela, J.; Nava, B.; Radicella, S.; Richardson, J.; Touzani, A.; Girgea Team

    2017-12-01

    This paper reviews scientific advances achieved by a North-South network between 2006 and 2016. These scientific advances concern solar terrestrial physics, atmospheric physics and space weather. This part B is devoted to the results and capacity building. Our network began in 1991, in solar terrestrial physics, by our participation in the two projects: International Equatorial Electrojet Year IEEY [1992-1993] and International Heliophysical Year IHY [2007-2009]. These two projects were mainly focused on the equatorial ionosphere in Africa. In Atmospheric physics our research focused on gravity waves in the framework of the African Multidisciplinary Monsoon Analysis project n°1 [2005-2009 ], on hydrology in the Congo river basin and on lightning in Central Africa, the most lightning part of the world. In Vietnam the study of a broad climate data base highlighted global warming. In space weather, our results essentially concern the impact of solar events on global navigation satellite system GNSS and on the effects of solar events on the circulation of electric currents in the earth (GIC). This research began in the framework of the international space weather initiative project ISWI [2010-2012]. Finally, all these scientific projects have enabled young scientists from the South to publish original results and to obtain positions in their countries. These projects have also crossed disciplinary boundaries and defined a more diversified education which led to the training of specialists in a specific field with knowledge of related scientific fields.

  19. Investigations in space-related molecular biology. [cryo-electron microscopic and diffraction studies on terrestrial and extraterrestrial specimens

    Science.gov (United States)

    Fernandez-Moran, H.; Pritzker, A. N.

    1974-01-01

    Improved instrumentation and preparation techniques for high resolution, high voltage cryo-electron microscopic and diffraction studies on terrestrial and extraterrestrial specimens are reported. Computer correlated ultrastructural and biochemical work on hydrated and dried cell membranes and related biological systems provided information on membrane organization, ice crystal formation and ordered water, RNA virus linked to cancer, lunar rock samples, and organometallic superconducting compounds. Apollo 11, 12, 14, and 15 specimens were analyzed

  20. Digital networks and their evolution - Space and terrestrial systems; Proceedings of the Thirty-third International Congress on Electronics and Twenty-sixth International Meeting on Space, Rome, Italy, Mar. 18-20, 1986

    Science.gov (United States)

    Among the topics presently discussed are the position of space and terrestrial systems in digital communications network evolution, research and experiments on broadband subscriber networks in Italy, ESA satellite communications activities and plans, research on the integrated switching of voice and video transmissions, advanced structures for digital broadband switching, and the use of Banyan networks for high throughput switching exchanges. Also considered are the interconnection of digital systems with different standards, standard compatibility of ISND terminals, the global plan for network layer addressing in open systems interconnection, videoconferencing, ISND and office automation, intelligent networks, the European Data Relay Satellite, the Space Station's data systems, and Columbus communications.

  1. Analysis of ICASA broadcasting frequency plan for possible use of TV white spaces for broadband access

    CSIR Research Space (South Africa)

    Masonta, MT

    2013-09-01

    Full Text Available Television white spaces (TVWS) are unused portion of TV spectrum as a result of analogue TV coverage planning and the migration to digital terrestrial TV (DTT). As a member of the International Telecommunications (ITU) Region 1, South African...

  2. Analogue computing methods

    CERN Document Server

    Welbourne, D

    1965-01-01

    Analogue Computing Methods presents the field of analogue computation and simulation in a compact and convenient form, providing an outline of models and analogues that have been produced to solve physical problems for the engineer and how to use and program the electronic analogue computer. This book consists of six chapters. The first chapter provides an introduction to analogue computation and discusses certain mathematical techniques. The electronic equipment of an analogue computer is covered in Chapter 2, while its use to solve simple problems, including the method of scaling is elaborat

  3. Volumetrically-Derived Global Navigation Satellite System Performance Assessment from the Earths Surface through the Terrestrial Service Volume and the Space Service Volume

    Science.gov (United States)

    Welch, Bryan W.

    2016-01-01

    NASA is participating in the International Committee on Global Navigation Satellite Systems (GNSS) (ICG)'s efforts towards demonstrating the benefits to the space user from the Earth's surface through the Terrestrial Service Volume (TSV) to the edge of the Space Service Volume (SSV), when a multi-GNSS solution space approach is utilized. The ICG Working Group: Enhancement of GNSS Performance, New Services and Capabilities has started a three phase analysis initiative as an outcome of recommendations at the ICG-10 meeting, in preparation for the ICG-11 meeting. The first phase of that increasing complexity and fidelity analysis initiative was recently expanded to compare nadir-facing and zenith-facing user hemispherical antenna coverage with omnidirectional antenna coverage at different distances of 8,000 km altitude and 36,000 km altitude. This report summarizes the performance using these antenna coverage techniques at distances ranging from 100 km altitude to 36,000 km to be all encompassing, as well as the volumetrically-derived system availability metrics.

  4. Analogue MIMO Detection

    Directory of Open Access Journals (Sweden)

    McNamara Darren

    2006-01-01

    Full Text Available In this contribution we propose an analogue receiver that can perform turbo detection in MIMO systems. We present the case for a receiver that is built from nonlinear analogue devices, which perform detection in a "free-flow" network (no notion of iterations. This contribution can be viewed as an extension of analogue turbo decoder concepts to include MIMO detection. These first analogue implementations report reductions of few orders of magnitude in the number of required transistors and in consumed energy, and the same order of improvement in processing speed. It is anticipated that such analogue MIMO decoder could bring about the same advantages, when compared to traditional digital implementations.

  5. Previously hidden low-energy ions: a better map of near-Earth space and the terrestrial mass balance

    International Nuclear Information System (INIS)

    André, Mats

    2015-01-01

    This is a review of the mass balance of planet Earth, intended also for scientists not usually working with space physics or geophysics. The discussion includes both outflow of ions and neutrals from the ionosphere and upper atmosphere, and the inflow of meteoroids and larger objects. The focus is on ions with energies less than tens of eV originating from the ionosphere. Positive low-energy ions are complicated to detect onboard sunlit spacecraft at higher altitudes, which often become positively charged to several tens of volts. We have invented a technique to observe low-energy ions based on the detection of the wake behind a charged spacecraft in a supersonic ion flow. We find that low-energy ions usually dominate the ion density and the outward flux in large volumes in the magnetosphere. The global outflow is of the order of 10 26 ions s –1 . This is a significant fraction of the total number outflow of particles from Earth, and changes plasma processes in near-Earth space. We compare order of magnitude estimates of the mass outflow and inflow for planet Earth and find that they are similar, at around 1 kg s −1 (30 000 ton yr −1 ). We briefly discuss atmospheric and ionospheric outflow from other planets and the connection to evolution of extraterrestrial life. (invited comment)

  6. Innovative Approaches for the Dissemination of Near Real-time Geostationary Satellite Data for Terrestrial and Space Weather Applications

    Science.gov (United States)

    Jedlovec, G.; McGrath, K.; Meyer, P. J.; Berndt, E.

    2017-12-01

    A GOES-R series receiving station has been installed at the NASA Marshall Space Flight Center (MSFC) to support GOES-16 transition-to-operations projects of NASA's Earth science program and provide a community portal for GOES-16 data access. This receiving station is comprised of a 6.5-meter dish; motor-driven positioners; Quorum feed and demodulator; and three Linux workstations for ingest, processing, display, and subsequent product generation. The Community Satellite Processing Package (CSPP) is used to process GOES Rebroadcast data from the Advanced Baseline Imager (ABI), Geostationary Lightning Mapper (GLM), Solar Ultraviolet Imager (SUVI), Extreme Ultraviolet and X-ray Irradiance Sensors (EXIS), and Space Environment In-Situ Suite (SEISS) into Level 1b and Level 2 files. GeoTIFFs of the imagery from several of these instruments are ingested into an Esri Arc Enterprise Web Map Service (WMS) server with tiled imagery displayable through a web browser interface or by connecting directly to the WMS with a Geographic Information System software package. These data also drive a basic web interface where users can manually zoom to and animate regions of interest or acquire similar results using a published Application Program Interface. While not as interactive as a WMS-driven interface, this system is much more expeditious with generating and distributing requested imagery. The legacy web capability enacted for the predecessor GOES Imager currently supports approximately 500,000 unique visitors each month. Dissemination capabilities have been refined to support a significantly larger number of anticipated users. The receiving station also supports NASA's Short-term Prediction, Research, and Transition Center's (SPoRT) project activities to dissemination near real-time ABI RGB products to National Weather Service National Centers, including the Satellite Analysis Branch, National Hurricane Center, Ocean Prediction Center, and Weather Prediction Center, where they

  7. Recent Advances in Atmospheric, Solar-Terrestrial Physics and Space Weather From a North-South network of scientists [2006-2016] PART A: TUTORIAL

    Science.gov (United States)

    Amory-Mazaudier, C.; Menvielle, M.; Curto, J-J.; Le Huy, M.

    2017-12-01

    This paper reviews scientific advances achieved by a North-South network between 2006 and 2016. These scientific advances concern Solar Terrestrial Physics, Atmospheric Physics and Space Weather. In this part A, we introduce knowledge on the Sun-Earth system. We consider the physical process of the dynamo which is present in the Sun, in the core of the Earth and also in the regions between the Sun and the Earth, the solar wind-magnetosphere and the ionosphere. Equations of plasma physics and Maxwell's equations will be recalled. In the Sun-Earth system there are permanent dynamos (Sun, Earth's core, solar wind - magnetosphere, neutral wind - ionosphere) and non-permanent dynamos that are activated during magnetic storms in the magnetosphere and in the ionosphere. All these dynamos have associated electric currents that affect the variations of the Earth's magnetic field which are easily measurable. That is why a part of the tutorial is also devoted to the magnetic indices which are indicators of the electric currents in the Sun-Earth system. In order to understand some results of the part B, we present some characteristics of the Equatorial region and of the electrodynamics coupling the Auroral and Equatorial regions.

  8. Filling-in of Far-Red and Near-Infrared Solar Lines by Terrestrial and Atmospheric Effects: Simulations and Space-Based Observations from SCIAMACHY and GOSAT

    Science.gov (United States)

    Joiner, J.; Yoshida, Y.; Vasilkov, A. P.; Middleton, E. M.; Campbell, P. K. E.; Yoshida, Y.; Kuse, A.; Corp, L. A.

    2012-01-01

    Mapping of terrestrial vegetation fluorescence from space is of interest because it can potentially provide global information on the functional status of vegetation including light use efficiency and global primary productivity that can be used for global carbon cycle modeling. Space-based measurement of solar-induced chlorophyll fluorescence is challenging, because its signal is small as compared with the much larger reflectance signal. Ground- and aircraft-based approaches have made use of the dark and spectrally-wide O2-A ( approx 760 nm) and O2-B (approx 690 nm) atmospheric features to detect the weak fluorescence signal. More recently, Joiner et al. and Frankenberg et al. focused on longer-wavelength solar Fraunhofer lines that can be observed with space-based instruments such as the currently operational GOSAT. They showed that fluorescence can be detected using Fraunhofer lines away from the far-red chlorophyll-a fluorescence peak even when the surface is relatively bright. Here, we build on that work by developing methodology to correct for instrumental artifacts that produce false filling-in signals that can bias fluorescence retrievals. We also examine other potential sources of filling-in at far-red and NIR wavelengths. Another objective is to explore the possibility of making fluorescence measurements from space with lower spectral resolution instrumentation than the GOSAT interferometer. We focus on the 866nm Ca II solar Fraunhofer line. Very few laboratory and ground-based measurements of vegetation fluorescence have been reported at wavelengths longer than 800 nm. Some results of fluorescence measurements of corn leaves acquired in the laboratory using polychromatic excitation at wavelengths shorter than 665nm show that at 866 nm, the measured signal is of the order of 0.1-0.2 mW/sq m/nm/sr. In this work, we use the following satellite observations: We use SCIAMACHY channel 5 in nadir mode that covers wavelengths between 773 and 1063nm at a spectral

  9. Filling-in of Far-Red and Near-Infrared Solar Lines by Terrestrial and Atmospheric Effects: Simulations and Space-Based Observations from SCHIAMACHY and GOSAT

    Science.gov (United States)

    Joiner, J.; Yoshida, Y.; Vasilkov, A. P.; Middleton, E. M.; Campbell, P. K. E.; Kuze, A.; Corp, L. A.

    2012-01-01

    Mapping of terrestrial vegetation fluorescence from space is of interest because it can potentially provide global information on the functional status of vegetation including light use efficiency and global primary productivity that can be used for global carbon cycle modeling. Space-based measurement of solar-induced chlorophyll fluorescence is challenging, because its signal is small as compared with the much larger reflectance signal. Ground- and aircraft-based approaches have made use of the dark and spectrally-wide 02-A (approx 760 nm) and O2-B (approx 690 nm) atmospheric features to detect the weak fluorescence signal. More recently, Joiner et a1. and Frankenberg et a1. focused on longer-wavelength solar Fraunhofer lines that can be observed with space-based instruments such as the currently operational GOSAT. They showed that fluorescence can be detected using Fraunhofer lines away from the far-red chlorophyll-a fluorescence peak even when the surface is relatively bright. Here, we build on that work by developing methodology to correct for instrumental artifacts that produce false filling-in signals that can bias fluorescence retrievals. We also examine other potential sources of filling-in at far-red and NIR wavelengths. Another objective is to explore the possibility of making fluorescence measurements from space with lower spectral resolution instrumentation than the GOSAT interferometer. We focus on the 866 nm Ca II solar Fraunhofer line. Very few laboratory and ground-based measurements of vegetation fluorescence have been reported at wavelengths longer than 800 mn. Some results of fluorescence measurements of corn leaves acquired in the laboratory using polychromatic excitation at wavelengths shorter than 665 nm show that at 866 nm, the measured signal is of the order of 0.1-0.2 mw/sq m/nm/sr. In this work we use the following satellite observations: We use SCIAMACHY channel 5 in nadir mode that covers wavelengths between 773 and 1063 nm at a

  10. Terrestrial magnetosphere

    International Nuclear Information System (INIS)

    Pande, D.C.; Agarwal, D.C.

    1982-01-01

    This paper presents a review about terrestrial magnetosphere. During the last few years considerable investigation have been carried out about the properties of Solar Wind and its interaction with planetary magnetic fields. It is therefore of high importance to accumulate all the investigations in a comprehensive form. The paper reviews the property of earth's magnetosphere, magnetosheath, magneto pause, polar cusps, bow shook and plasma sheath. (author)

  11. Biosignature Preservation Vulnerability Associated with Stress Response Metabolic Redox Mode Switching in a Mars Analogue Coupled Microbial Mat Transiting Near-Space

    Science.gov (United States)

    Archer, R.; Ralat, A.

    2016-05-01

    Examination of a coupled microbial mat recovered from Death Valley failed to detect rosickyte, both before and after exposure to near-space conditions; associated redox proxies suggest diagenesis caused by rapid adaptive microbial stress response.

  12. Terrestrial radioecology

    International Nuclear Information System (INIS)

    Ohmomo, Yoichiro

    1992-01-01

    Environmental radioecology is a science of studying radionuclide transfer and distribution in the environmental ecosystem and the effects of radiation of the ecosystem. This review highlights radionuclide transfer to crops. There is, however, limited data available on this field in Japan. Therefore, a history of environmental radioecological study in Japan is briefly mentioned: radioecological study has been reflected by social backgrounds, including nuclear explosion and peaceful application of radionuclides. In view of the relationship between siting of nuclear installations and dietary habits for Japanese, research on hydrological radioecology has actually preceded that of terrestrial radioecology. Transfer parameters are discussed in terms of deposition velosity, interception fraction, environmental halftimes, and transfer coefficients from soils to crops. (N.K.) 50 refs

  13. Comparative Exploration of the Structure-Activity Space of Clonedα-Like Octopamine Receptors from a Marine and a Terrestrial Arthropod.

    Science.gov (United States)

    Dalwadi, Dhwanil A; Schetz, John A

    2017-09-01

    The α -like octopamine receptors (OctR) are believed to be the evolutionary precursor to the vertebrate α 2 -adrenergic receptors ( α 2 -ARs) based upon sequence similarity and the ability to interact with norepinephrine and a number of compounds that bind with high affinity to α 2 -ARs. Barnacles and fruit flies are two prominent model marine and terrestrial representatives of the Arthropoda phylum, and although α -like OctRs have been cloned from Balanus improvisus (BiOctR) and Drosophila melanogaster (DmOctR), little is known about the structure-activity space for these important species. A diverse panel of 22 probes spanning different structural classes were employed to interrogate the structure-activity of the BiOctR and DmOctR. While BiOctR and DmOctR exhibited similar functional profiles for mammalian biogenic amine G protein-coupled receptor agonists and antagonists, some ligands had dramatically different mechanisms of action. For instance, significant differences in the efficacy for some agonists were observed, including that vertebrate biogenic amines structurally related to octopamine acted as superagonists at the DmOctR but partial agonists at the BiOctR, and the two species diverged in their sensitivities to the α 2 -AR antagonist [ 3 H]rauwolscine. Furthermore, sodium enhanced [ 3 H]rauwolscine's interactions with the BiOctR, but not at a vertebrate α 2 -AR. Molecular mechanistic studies indicate that rauwolscine interacts with the BiOctR, DmOctR, and α 2C -adrenergic receptor at an allosteric site. In addition, compounds that acted as agonists at a cloned α -like BiOctR also induced a hyperactivity response in Balanus cyprids mediated by the α -like OctR, suggesting that the receptor may serve as a higher throughput proxy for discovering compounds with potential cyprid deterrent properties. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

  14. Burfellshraun - a terrestrial analogue to recent volcanism on mars

    DEFF Research Database (Denmark)

    Haack, Henning; Dall, Jørgen; Rossi, Matti

    2004-01-01

    The up to 2000 km long and very young lava flows from Elysium Planitia to Amazonis Planitia on Mars often include km-sized rafting plates. We have studied the unique Burfellshraun lava field east of lake Myvatn in Iceland that, although on a much smaller scale, share many characteristics of the M...

  15. Terrestrial ecology

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The main effort of the Terrestrial Ecology Division has been redirected to a comprehensive study of the Espiritu Santo Drainage Basin located in northeastern Puerto Rico. The general objective are to provide baseline ecological data for future environmental assessment studies at the local and regional levels, and to provide through an ecosystem approach data for the development of management alternatives for the wise utilization of energy, water, and land resources. The interrelationships among climate, vegetation, soils, and man, and their combined influence upon the hydrologic cycle will be described and evaluated. Environmental management involves planning and decision making, and both require an adequate data base. At present, little is known about the interworkings of a complete, integrated system such as a drainage basin. A literature survey of the main research areas confirmed that, although many individual ecologically oriented studies have been carried out in a tropical environment, few if any provide the data base required for environmental management. In view of rapidly changing socio-economic conditions and natural resources limitations, management urgently requires data from these systems: physical (climatological), biological, and cultural. This integrated drainage basin study has been designed to provide such data. The scope of this program covers the hydrologic cycle as it is affected by the interactions of the physical, biological, and cultural systems

  16. Natural Analogue Synthesis Report

    Energy Technology Data Exchange (ETDEWEB)

    A. M. Simmons

    2002-05-01

    The purpose of this report is to present analogue studies and literature reviews designed to provide qualitative and quantitative information to test and provide added confidence in process models abstracted for performance assessment (PA) and model predictions pertinent to PA. This report provides updates to studies presented in the ''Yucca Mountain Site Description'' (CRWMS M and O 2000 [151945], Section 13) and new examples gleaned from the literature, along with results of quantitative studies conducted specifically for the Yucca Mountain Site Characterization Project (YMP). The intent of the natural analogue studies was to collect corroborative evidence from analogues to demonstrate additional understanding of processes expected to occur during postclosure at a potential Yucca Mountain repository. The report focuses on key processes by providing observations and analyses of natural and anthropogenic (human-induced) systems to improve understanding and confidence in the operation of these processes under conditions similar to those that could occur in a nuclear waste repository. The process models include those that represent both engineered and natural barrier processes. A second purpose of this report is to document the various applications of natural analogues to geologic repository programs, focusing primarily on the way analogues have been used by the YMP. This report is limited to providing support for PA in a confirmatory manner and to providing corroborative inputs for process modeling activities. Section 1.7 discusses additional limitations of this report. Key topics for this report are analogues to emplacement drift degradation, waste form degradation, waste package degradation, degradation of other materials proposed for the engineered barrier, seepage into drifts, radionuclide flow and transport in the unsaturated zone (UZ), analogues to coupled thermal-hydrologic-mechanical-chemical processes, saturated zone (SZ) transport

  17. NATURAL ANALOGUE SYNTHESIS REPORT

    International Nuclear Information System (INIS)

    Simmons, A.M.

    2004-01-01

    The purpose of this report is to present analogue studies and literature reviews designed to provide qualitative and quantitative information to test and provide added confidence in process models abstracted for performance assessment (PA) and model predictions pertinent to PA. This report provides updates to studies presented in the Yucca Mountain Site Description (CRWMS M and O 2000 [151945], Section 13) and new examples gleaned from the literature along with results of quantitative studies conducted specifically for the Yucca Mountain Project (YMP). The intent of the natural analogue studies was to collect corroborative evidence from analogues to demonstrate additional understanding of processes expected to occur during postclosure at a potential Yucca Mountain repository. The report focuses on key processes by providing observations and analyses of natural and anthropogenic (human-induced) systems to improve understanding and confidence in the operation of these processes under conditions similar to those that could occur in a nuclear waste repository. The process models include those that represent both engineered and natural barrier processes. A second purpose of this report is to document the various applications of natural analogues to geologic repository programs, focusing primarily on the way analogues have been used by the YMP. This report is limited to providing support for PA in a confirmatory manner and to providing corroborative inputs for process modeling activities. Section 1.7 discusses additional limitations of this report. Key topics for this report are analogues to emplacement-drift degradation, waste-form degradation, waste-package degradation, degradation of other materials proposed for the engineered barrier, seepage into drifts, radionuclide flow and transport in the unsaturated zone (UZ), analogues to coupled thermal-hydrologic-mechanical-chemical processes, saturated-zone (SZ) transport, impact of radionuclide release on the biosphere

  18. CEC natural analogue working group

    International Nuclear Information System (INIS)

    Come, B.; Chapman, N.A.

    1986-01-01

    The second meeting of the CEC Natural Analogue Working Group took place on June 17-19, 1986, hosted by the Swiss NAGRA in Interlaken (CH). A review of recent progress in natural analogue programmes was carried out, and complemented by detailed discussions about geomicrobiology, archaeological analogues, natural colloids, and use of analogues to increase confidence in safety assessments for radioactive waste disposal. A statement drafted by the Group, and the presentations made, are put together in this report

  19. The ratio of animal protein intake to potassium intake is a predictor of bone resorption in space flight analogues and in ambulatory subjects

    Science.gov (United States)

    Zwart, Sara R.; Hargens, Alan R.; Smith, Scott M.

    2004-01-01

    BACKGROUND: Bone loss is a critical concern for space travelers, and a dietary countermeasure would be of great benefit. Dietary protein and potassium-associated bicarbonate precursors may have opposing effects on the acid-base balance in the body and therefore on bone loss. OBJECTIVE: In 2 studies, we examined the ability of dietary protein and potassium to predict markers of bone metabolism. DESIGN: In the first study, 8 pairs of male identical twins were assigned to 1 of 2 groups: bed rest (sedentary, or SED, group) or bed rest with supine treadmill exercise in a lower-body negative pressure chamber (EX group). In a second study, groups of 4 subjects lived in a closed chamber for 60 or 91 d, and dietary data were collected for two or three 5-d sessions. Urinary calcium, N-telopeptide, and pyridinium cross-links were measured before bed rest; on bed rest days 5-6, 12-13, 19-20, and 26-27; and daily during the chamber studies. Data were analyzed by Pearson's correlation (P animal protein intake to potassium intake was significantly correlated with N-telopeptide in the SED group during bed rest weeks 3 and 4 (r = 0.77 and 0.80) and during the 91-d chamber study (r = 0.75). The ratio of animal protein intake to potassium intake was positively correlated with pyridinium cross-links before bed rest in the EX group (r = 0.83), in the EX group during bed rest week 1 (r = 0.84), and in the SED group during bed rest week 2 (r = 0.72) but not during either chamber study. In both studies, these relations were not significant with the ratio of vegetable protein intake to potassium intake. CONCLUSIONS: The ratio of animal protein intake to potassium intake may affect bone in ambulatory and bed-rest subjects. Changing this ratio may help to prevent bone loss on Earth and during space flight.

  20. CEC Natural Analogue Working Group

    International Nuclear Information System (INIS)

    Come, B.; Chapman, N.A.

    1989-01-01

    The central theme for the third meeting of the CEC analogue working group was ''How can analogue data be used for performance assessments, both in support of the results and for presentation to the public''. This report puts together the most recent achievements in this field, together with a review of on-going natural analogue programmes

  1. From the Canadian High Arctic to Mars by Analogue

    Science.gov (United States)

    Soare, R. J.; Pollard, W. H.

    2002-12-01

    Planetary scientists are limited in their understanding of physical bodies in the solar system by the lack of primary data or knowledge. Analogue science is science practised in absentia, precisely in those instances when a non-terrestrial physical environment lies beyond one's direct, empirical grasp. Recognising that some environments on Earth may mirror present or past conditions on Mars, planetary scientists have invoked terrestrial analogues with increasing regularity over the last thirty years as fonts of putative understanding. Notwithstanding its ubiquity in planetary science, analogical reasoning has stood, by and large, unconstrained by rules or guidelines of usage. In order to redress this imbalance we propose to take two steps: 1. introduce primary data on newly discovered pingos at Axel Heiberg Island in the Canadian High Arctic, and 2. coalesce these and related data on Martian glacial, peri-glacial and fluvio-glacial landforms as a model with which to evaluate the meaningfulness of analogical reasoning in planetary science.

  2. Natural analogue working group

    International Nuclear Information System (INIS)

    Come, B.; Chapman, N.

    1986-01-01

    A Natural Analogue Working Group was established by the Commission of the European Communities in 1985. The purpose of this group is to bring together modellers with earth scientists and others, so that maximum benefit can be obtained from natural analogue studies with a view to safe geological disposal of radioactive waste. The first meeting of this group was held in Brussels from November 5 to 7, 1985. The discussions mainly concerned the identification of the modellers' needs and of the earth scientists' capacity to provide for them. Following the debates, a written statement was produced by the Group; this document forms the core of the present Report. Notes and outlines of many of the presentations made are grouped in four appendixes. The valuable contribution of all those involved in the meeting is gratefully acknowledged

  3. The Palmottu analogue project

    International Nuclear Information System (INIS)

    Ahonen, L.; Blomqvist, R.; Suksi, J.

    1993-01-01

    The report gives a summary of the results of investigations carried out in 1992 at the Palmottu natural analogue study site, which is a small U-Th mineralization in Nummi-Pusula, southwestern Finland. Additionally, the report includes several separate articles dealing with various aspects of the Palmottu Analogue Project: (1) deep groundwater flow, (2) interpretation of hydraulic connections, (3) characterization of groundwater colloids, (4) uranium mineral-groundwater equilibrium, (5) water-rock interaction and (6) modelling of in situ matrix diffusion. The Palmottu Analogue Project aims at a more profound understanding of radionuclide transport processes in fractured crystalline bedrock. The essential factors controlling transport are groundwater flow and interaction between water and rock. Accordingly, the study includes (1) structural interpretations partly based on geophysical measurements, (2) hydrological studies including hydraulic drill-hole measurements, (3) flow modelling, (4) hydrogeochemical characterization of groundwater, uranium chemistry and colloid chemistry, (5) mineralogical studies, (6) geochemical interpretation and modelling, (7) studies of radionuclide mobilization and retardation including matrix diffusion, and (8) modelling of uranium series data. Palaeohydrogeological aspects, due to the anticipated future glaciation of the Fennoscandian Shield, are of special interest. Quaternary sediments are studied to gain information on post-glacial migration in the overburden. (orig.)

  4. Advanced Li batteries for terrestrial balloons, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — For future advanced terrestrial balloon missions, NASA requires energy dense and power dense energy storage solutions significantly exceeding the performance of...

  5. The Application of an Online Data Visualization Tool, Ptplot, in the World Data Center (WDC for Solar-Terrestrial Science (STS in IPS Radio and Space Services, Australia

    Directory of Open Access Journals (Sweden)

    K Wang

    2013-02-01

    Full Text Available Ptplot is a set of two dimensional signal plotters components written in Java with multiple properties, such as being embeddable in applets or applications, utilizing automatic or manual tick marks, logarithmic axes, infinite zooming, and much more. The World Data Centre of IPS applies Ptplot as a multiple function online data plot tool by converting various text format data files into Ptplot recognizable XML files with the AWK language. At present, Ptplot has allowed eight archived solar-terrestrial science data sets to be easily plotted, viewed, and downloaded from the IPS web site.

  6. Space life sciences: search for signatures of life, and space flight environmental effects on the nervous system.

    Science.gov (United States)

    2004-01-01

    This volume contains selected papers of the Joint COSPAR-IAC event "Search for signatures of life in the solar system, terrestrial analogues and simulation experiments" held during the World Space Congress 2002 in Houston, Texas, USA. The first section of the volume reports on the rich variety of terrestrial microbial communities adapted to extreme environments, such as microbial life at very low temperatures in permafrost and ice layers, at high salt concentrations, as inhabitants of rocks and the microbial recolonization of impact-shocked rocks. These communities are suggested to serve as analogues for extraterrestrial habitats, which are also described in this section. The second section deals with the detection of biomarkers and signatures from extinct life on Earth, which might provide clues for detection of potential extraterrestrial biomarkers. This section is followed by reports of experiments in space and in the laboratory simulating space conditions, such as the prebiotic organic chemistry, the chemistry of dust particles to be detected during the Cassini mission to Saturn, as well as the photochemistry of biological systems exposed to space or planetary surface conditions. The second part of the issue contains papers from the session "The nervous system: space flight environmental factors effects--present results and new perspectives." The presentations in this session explored various aspects of the effects of exposure to protons and heavy particles on central nervous system function and on behavior. The second series of papers examines the effects of exposure to heavy particles and protons on neurochemistry and on behavior.

  7. ACTINOMYCIN D ANALOGUES

    DEFF Research Database (Denmark)

    1997-01-01

    acids, $g(b)-amino acids and/or longer chain $g(v)-amino acids, and a difunctional group which preferably is a cyclic entity, in particular, an aromatic or heteroaromatic entity acting as an intercalator group. Specific compounds and a library of such compounds may be prepared using conventional solid......The present invention relates to new compounds being structurally and functionally similar to Actinomycin D and to combinatorial libraries of such compounds. The Actinomycin D analogues according to the present invention comprise two linear or cyclic peptide moieties constituted by $g(a)-amino...

  8. Transaxial analogue tomography

    International Nuclear Information System (INIS)

    Duinker, S.; Geluk, R.J.; Mulder, H.

    1978-01-01

    After an introduction on computerized tomography (CT) scanners summarizing the various generations, the general outline of the concept of a transaxial tomography system is given, which is entirely based on analogue instead of digital techniques (AT system). In particular, the use of X-ray image-intensifier systems as a means of detecting the transmission profiles of the object in a so-called half-field detection method are discussed as well as various possibilities of detector scanning. It is further discussed how in a purely electronic way with the aid of a scan-converter, density profiles representative of parallel beams can be derived from the family of profiles as obtained from the fan-shaped beams in the actual experiment. A practical opto-electronic solution of the analogue spatial filtering problem is described as to how to process, on a real-time basis, parallel density profiles so that after back-projection tomographic images which are free from point-spreading effects will be obtained. Finally, after a brief indication of certain technical details for which corrective measures have to be worked out in the course of practical realization, the main relative advantages of AT scanners in comparison to CT scanners are enumerated. (Auth.)

  9. Measurement of Air Pollution from Satellites (MAPS) Office of Space and Terrestrial Applications - 3 (OSTA3) Carbon Monoxide 5 degree by 5 degree data

    Data.gov (United States)

    National Aeronautics and Space Administration — MAPS Overview The MAPS experiment measures the global distribution of carbon monoxide (CO) mixing ratios in the free troposphere. Because of MAPS' previous flights...

  10. Measurement of Air Pollution from Satellites (MAPS) Office of Space and Terrestrial Applications - 3 (OSTA3) Carbon Monoxide Second by Second data

    Data.gov (United States)

    National Aeronautics and Space Administration — MAPS Overview The MAPS experiment measures the global distribution of carbon monoxide (CO) mixing ratios in the free troposphere. Because of MAPS' previous flights...

  11. Terrestrial Laser Scanner Two-Face Measurements for Analyzing the Elevation-Dependent Deformation of the Onsala Space Observatory 20-m Radio Telescope's Main Reflector in a Bundle Adjustment.

    Science.gov (United States)

    Holst, Christoph; Schunck, David; Nothnagel, Axel; Haas, Rüdiger; Wennerbäck, Lars; Olofsson, Henrik; Hammargren, Roger; Kuhlmann, Heiner

    2017-08-09

    For accurate astronomic and geodetic observations based on radio telescopes, the elevation-dependent deformation of the radio telescopes' main reflectors should be known. Terrestrial laser scanning has been used for determining the corresponding changes of focal lengths and areal reflector deformations at several occasions before. New in this publication is the situation in which we minimize systematic measurement errors by an improved measurement and data-processing concept: Sampling the main reflector in both faces of the laser scanner and calibrating the laser scanner in situ in a bundle adjustment. This concept is applied to the Onsala Space Observatory 20-m radio telescope: The focal length of the main reflector decreases by 9.6 mm from 85 ∘ to 5 ∘ elevation angle. Further local deformations of the main reflector are not detected.

  12. Terrestrial Laser Scanner Two-Face Measurements for Analyzing the Elevation-Dependent Deformation of the Onsala Space Observatory 20-m Radio Telescope’s Main Reflector in a Bundle Adjustment

    Directory of Open Access Journals (Sweden)

    Christoph Holst

    2017-08-01

    Full Text Available For accurate astronomic and geodetic observations based on radio telescopes, the elevation-dependent deformation of the radio telescopes’ main reflectors should be known. Terrestrial laser scanning has been used for determining the corresponding changes of focal lengths and areal reflector deformations at several occasions before. New in this publication is the situation in which we minimize systematic measurement errors by an improved measurement and data-processing concept: Sampling the main reflector in both faces of the laser scanner and calibrating the laser scanner in situ in a bundle adjustment. This concept is applied to the Onsala Space Observatory 20-m radio telescope: The focal length of the main reflector decreases by 9.6 mm from 85 ∘ to 5 ∘ elevation angle. Further local deformations of the main reflector are not detected.

  13. Alligator Rivers analogue project

    International Nuclear Information System (INIS)

    Duerden, P.

    1990-01-01

    Australian Nuclear Science and Technology Organization has extensively evaluated uranium ore bodies in the Alligator Rivers Uranium Province in Australia as analogues of radioactive waste repositories. The work was extended for a three-year program as an international project based on the Koongarra uranium deposit and sponsored by the OECD Nuclear Energy Agency. The technical program comprises six major sub-projects involving modelling and experimental work: modelling of radionuclide migration; hydrogeology of the Koongarra uranium deposit; uranium/thorium series disequilibria studies; groundwater and colloid studies; fission product studies; transuranic nuclide studies; an outline of the technical programs and a summary of progress in the technical sub-projects is given. This is followed by a series of technical reports which briefly describe current research tasks, and which have been separately indexed

  14. A Short Term Analogue Memory

    DEFF Research Database (Denmark)

    Shah, Peter Jivan

    1992-01-01

    A short term analogue memory is described. It is based on a well-known sample-hold topology in which leakage currents have been minimized partly by circuit design and partly by layout techniques. Measurements on a test chip implemented in a standard 2.4 micron analogue CMOS process show a droop...

  15. Efficacy of Antimicrobials on Bacteria Cultured in a Spaceflight Analogue

    Science.gov (United States)

    Nickerson, CA; Wotring, Virginia; Barrila, Jennifer; Crabbe, Aurelie; Castro, Sarah; Davis, Richard; Rideout, April; McCarthy, Breanne; Ott, C. Mark

    2014-01-01

    As humans travel in space, they will interact with microbial flora from themselves, other crewmembers, their food, and the environment. While evaluations of microbial ecology aboard the Mir and ISS suggest a predominance of common environmental flora, the presence of (and potential for) infectious agents has been well documented. Likewise, pathogens have been detected during preflight monitoring of spaceflight food, resulting in the disqualification of that production lot from flight. These environmental and food organisms range from the obligate pathogen, Salmonella enterica serovar Typhimurium (S. Typhimurium), which has been responsible for disqualification and removal of food destined for ISS and has previously been reported from Shuttle crew refuse, to the opportunistic pathogen Staphylococcus aureus, isolated numerous times from ISS habitable compartments and the crew. Infectious disease events have affected spaceflight missions, including an upper respiratory infection that delayed the launch of STS-36 and an incapacitating Pseudomonas aeruginosa urinary tract infection of a crewmember during Apollo 13. These observations indicate that the crew has the potential to be exposed to obligate and opportunistic pathogens. This risk of exposure is expected to increase with longer mission durations and increased use of regenerative life support systems. As antibiotics are the primary countermeasure after infection, determining if their efficacy during spaceflight missions is comparable to terrestrial application is of critical importance. The NASA Rotating Wall Vessel (RWV) culture system has been successfully used as a spaceflight culture analogue to identify potential alterations in several key microbial characteristics, such as virulence and gene regulation, in response to spaceflight culture. We hypothesized that bacteria cultured in the low fluid shear RWV environment would demonstrate changes in efficacy of antibiotics compared to higher fluid shear controls

  16. Classification and segmentation of orbital space based objects against terrestrial distractors for the purpose of finding holes in shape from motion 3D reconstruction

    Science.gov (United States)

    Mundhenk, T. Nathan; Flores, Arturo; Hoffman, Heiko

    2013-12-01

    3D reconstruction of objects via Shape from Motion (SFM) has made great strides recently. Utilizing images from a variety of poses, objects can be reconstructed in 3D without knowing a priori the camera pose. These feature points can then be bundled together to create large scale scene reconstructions automatically. A shortcoming of current methods of SFM reconstruction is in dealing with specular or flat low feature surfaces. The inability of SFM to handle these places creates holes in a 3D reconstruction. This can cause problems when the 3D reconstruction is used for proximity detection and collision avoidance by a space vehicle working around another space vehicle. As such, we would like the automatic ability to recognize when a hole in a 3D reconstruction is in fact not a hole, but is a place where reconstruction has failed. Once we know about such a location, methods can be used to try to either more vigorously fill in that region or to instruct a space vehicle to proceed with more caution around that area. Detecting such areas in earth orbiting objects is non-trivial since we need to parse out complex vehicle features from complex earth features, particularly when the observing vehicle is overhead the target vehicle. To do this, we have created a Space Object Classifier and Segmenter (SOCS) hole finder. The general principle we use is to classify image features into three categories (earth, man-made, space). Classified regions are then clustered into probabilistic regions which can then be segmented out. Our categorization method uses an augmentation of a state of the art bag of visual words method for object categorization. This method works by first extracting PHOW (dense SIFT like) features which are computed over an image and then quantized via KD Tree. The quantization results are then binned into histograms and results classified by the PEGASOS support vector machine solver. This gives a probability that a patch in the image corresponds to one of three

  17. Cobalamin analogues in humans

    DEFF Research Database (Denmark)

    Hardlei, Tore Forsingdal; Obeid, Rima; Herrmann, Wolfgang

    2013-01-01

    BACKGROUND: Haptocorrin (HC) carries cobalamin analogues (CorA), but whether CorA are produced in the body is unknown. All cobalamins (Cbl) to the foetus are delivered by the Cbl-specific protein transcobalamin (TC), and therefore analysis of cord serum for CorA may help to clarify the origin...... of CorA. METHODS: HC-CorA were quantified in paired samples of cord serum from newborns and serum from mothers (n = 69). RESULTS: The CorA-concentration was higher in cord serum (median = 380, range: 41-780 pmol/L) than in serum from the mothers (median = 160, range: 64-330 pmol/L), (p...-analysis showed CorA-peaks with retention times of 13.5, 14,5 and 16.5 min in samples from both the mother and cord serum. The peak with retention time 16.5 min constituted 24% (mother) and 45% (cord serum) of the total amount CorA, and eluted as does dicyanocobinamide. CONCLUSION: Our results support that Cor...

  18. Space-time analysis of the Seismic Waves propagation and World Wide Lightning Location Network data association with the Terrestrial Gamma-ray Flashes detected by the Fermi Gamma-ray Burst Monitor

    International Nuclear Information System (INIS)

    Sorokin, L.

    2017-01-01

    The natural high intensity sub-millisecond electromagnetic pulses associated with seismic waves from earthquakes can trigger +CG, -CG and IC lightning discharges, transient luminous events (TLEs) and non luminous events as TGFS. The lightning discharges with higher peak currents are more probable during the moments when seismic waves from earthquakes pass through a place of lightning. Huge charge transfer of triggered +CG, -CG and IC lightning discharges can radiate powerful electromagnetic emission. Space-time analysis of the seismic wave’s propagation and WWLLN data was done together with the second Fermi GBM Terrestrial Gamma-ray Flashes (TGF) Catalog. A total number of 1203 events from the WWLLN associations table were associated with the entrance the exact seismic waves from earthquakes in the place of lightning. Only 11 events from 1214 associations were rejected. After that the full list of 1049 TGFs has been checked out. As the result the 1038 TGFS has been associated with earthquakes. Among them 42 events with time difference exceeding ±100 sec were found. As the result 996 events get inside the time interval for the space-time analysis ±100 sec, they correspond to 95% from the total number of 1049 TGFS. The probability density function for the Time difference data was calculated and more preferably can be explained by the probability density functions of Cauchy distribution. The Phases of Seismic Waves and earthquakes magnitude associated with selected 996 TGFS from WWLLN associations table were studied. (author)

  19. Chemoenzymatic preparation of germacrene analogues.

    Science.gov (United States)

    Cascón, Oscar; Touchet, Sabrina; Miller, David J; Gonzalez, Veronica; Faraldos, Juan A; Allemann, Rudolf K

    2012-10-09

    A small library of novel germacrenes was generated using a combination of two plant enzymes, germacrene A synthase, and D synthase and modified farnesyl diphosphate (FDP) analogues. This chemoenzymatic approach allows the preparation of potentially valuable volatiles for biological studies.

  20. Chemoenzymatic preparation of germacrene analogues

    OpenAIRE

    Cascón, Oscar; Touchet, Sabrina; Miller, David James; Gonzalez, Veronica; Faraldos, Juan A.; Allemann, Rudolf Konrad

    2012-01-01

    A small library of novel germacrenes was generated using a combination of two plant enzymes, germacrene A synthase, and D synthase and modified farnesyl diphosphate (FDP) analogues. This chemoenzymatic approach allows the preparation of potentially valuable volatiles for biological studies.

  1. Spatial resolution of tropical terrestrial CO2 fluxes inferred using space-borne column CO2 sampled in different earth orbits: the role of spatial error correlations

    Directory of Open Access Journals (Sweden)

    H. Bösch

    2011-09-01

    Full Text Available We use realistic numerical experiments to assess the sensitivity of 8-day CO2 flux estimates, inferred from space-borne short-wave infrared measurements of column-averaged CO2 dry air mixing ratio XCO2, to the choice of Earth observing orbit. We focus on three orbits: (1 a low-inclination circular orbit used by the NASA Tropical Rainfall Measuring Mission (TRMM; (2 a sun-synchronous orbit used by the Japanese Greenhouse Gases Observing SATellite (GOSAT and proposed for the NASA Orbiting Carbon Observatory (OCO-2 instrument; and (3 a precessing orbit used by the International Space Station (ISS. For each orbit, we assume an instrument based on the specification of the OCO-2; for GOSAT we use the relevant instrument specification. Sun-synchronous orbits offer near global coverage within a few days but have implications for the density of clear-sky measurements. The TRMM and ISS orbits intensively sample tropical latitudes, with sun-lit clear-sky measurements evenly distributed between a.m./p.m. For a specified spatial resolution for inferred fluxes, we show there is a critical number of measurements beyond which there is a disproportionately small decrease in flux uncertainty. We also show that including spatial correlations for measurements and model errors (of length 300 km reduces the effectiveness of high measurement density for flux estimation, as expected, and so should be considered when deciding sampling strategies. We show that cloud-free data from the TRMM orbit generally can improve the spatial resolution of CO2 fluxes achieved by OCO-2 over tropical South America, for example, from 950 km to 630 km, and that combining data from these low-inclination and sun-synchronous orbits have the potential to reduce this spatial length further. Decreasing the length of the error correlations to 50 km, reflecting anticipated future improvements to transport models, results in CO2 flux estimates on spatial scales that approach those observed by

  2. Research of the Effect Caused by Terrestrial Power Sources on the Near-Earth Space above China based on DEMETER Satellite Data

    Science.gov (United States)

    Zhang, C.; Wu, J.; Ma, Q.

    2017-12-01

    The environmental effect on the ionosphere caused by man-made power line emission (PLE) and power line harmonic radiation (PLHR) has become an increasing concern. Based on the observed data of 6.5 operating years of DEMETER satellite, by scanning the electric field power density time-frequency spectrograms, 133 PLHR events with central frequencies from 500 Hz to 4.5 kHz are detected in the near-Earth space above China. Among the 133 events, 129 events have PLE events at the base power system frequency (50 Hz in China). The duration time of every PLE event covers that of the corresponding PLHR event totally. As the same with PLHR, PLE is also propagating in whistler mode in the ionosphere. In two events that are detected in the conjugate region of Australian NWC VLF transmitter, radiations with line structure in the vicinity of 19.8 kHz are detected. There are 5 lines distributed from about 19.7 kHz to 19.9 kHz, which are in accordance with the frequency range of NWC transmitted signals. The frequency spacing of the 5 lines is exactly 50 Hz and the bandwidth of each line is about 10 Hz. The electric field power density of the line structure radiation is at the same level with the corresponding PLE, much higher than that of PLHR. The line structure radiations suggest possible modulation of VLF signals by PLE. At last, the variation of ionospheric parameters measured by DEMETER in relation with PLHR is analyzed statistically. As the revisiting orbits of DEMETER pass over the same area with nearly no deviation and at the same time of day, for each PLHR event, we check and average the parameters of 3 revisiting orbits before and after the event respectively. Combined with the event orbit, the variations of these parameters can be obtained. There are totally 5 tendencies: no variation, ascending, descending, crest and trough. Only a few events show no variation. Though there are differences in other 4 tendencies, none of the parameters show extremely preferences on one

  3. An ESA roadmap for geobiology in space exploration

    Science.gov (United States)

    Cousins, Claire R.; Cockell, Charles S.

    2016-01-01

    Geobiology, and in particular mineral-microbe interactions, has a significant role to play in current and future space exploration. This includes the search for biosignatures in extraterrestrial environments, and the human exploration of space. Microorganisms can be exploited to advance such exploration, such as through biomining, maintenance of life-support systems, and testing of life-detection instrumentation. In view of these potential applications, a European Space Agency (ESA) Topical Team "Geobiology in Space Exploration" was developed to explore these applications, and identify research avenues to be investigated to support this endeavour. Through community workshops, a roadmap was produced, with which to define future research directions via a set of 15 recommendations spanning three key areas: Science, Technology, and Community. These roadmap recommendations identify the need for research into: (1) new terrestrial space-analogue environments; (2) community level microbial-mineral interactions; (3) response of biofilms to the space environment; (4) enzymatic and biochemical mineral interaction; (5) technical refinement of instrumentation for space-based microbiology experiments, including precursor flight tests; (6) integration of existing ground-based planetary simulation facilities; (7) integration of fieldsite biogeography with laboratory- and field-based research; (8) modification of existing planetary instruments for new geobiological investigations; (9) development of in situ sample preparation techniques; (10) miniaturisation of existing analytical methods, such as DNA sequencing technology; (11) new sensor technology to analyse chemical interaction in small volume samples; (12) development of reusable Lunar and Near Earth Object experimental platforms; (13) utility of Earth-based research to enable the realistic pursuit of extraterrestrial biosignatures; (14) terrestrial benefits and technological spin-off from existing and future space

  4. Scientific results and lessons learned from an integrated crewed Mars exploration simulation at the Rio Tinto Mars analogue site

    Science.gov (United States)

    Orgel, Csilla; Kereszturi, Ákos; Váczi, Tamás; Groemer, Gernot; Sattler, Birgit

    2014-02-01

    Between 15 and 25 April 2011 in the framework of the PolAres programme of the Austrian Space Forum, a five-day field test of the Aouda.X spacesuit simulator was conducted at the Rio Tinto Mars-analogue site in southern Spain. The field crew was supported by a full-scale Mission Control Center (MCC) in Innsbruck, Austria. The field telemetry data were relayed to the MCC, enabling a Remote Science Support (RSS) team to study field data in near-real-time and adjust the flight planning in a flexible manner. We report on the experiences in the field of robotics, geophysics (Ground Penetrating Radar) and geology as well as life sciences in a simulated spaceflight operational environment. Extravehicular Activity (EVA) maps had been prepared using Google Earth and aerial images. The Rio Tinto mining area offers an excellent location for Mars analogue simulations. It is recognised as a terrestrial Mars analogue site because of the presence of jarosite and related sulphates, which have been identified by the NASA Mars Exploration Rover "Opportunity" in the El Capitan region of Meridiani Planum on Mars. The acidic, high ferric-sulphate content water of Rio Tinto is also considered as a possible analogue in astrobiology regarding the analysis of ferric sulphate related biochemical pathways and produced biomarkers. During our Mars simulation, 18 different types of soil and rock samples were collected by the spacesuit tester. The Raman results confirm the presence of minerals expected, such as jarosite, different Fe oxides and oxi-hydroxides, pyrite and complex Mg and Ca sulphates. Eight science experiments were conducted in the field. In this contribution first we list the important findings during the management and realisation of tests, and also a first summary of the scientific results. Based on these experiences suggestions for future analogue work are also summarised. We finish with recommendations for future field missions, including the preparation of the experiments

  5. Introduced Terrestrial Species (Future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — These data represent predicted future potential distributions of terrestrial plants, animals, and pathogens non-native to the Middle-Atlantic region. These data are...

  6. Extreme solar-terrestrial events

    Science.gov (United States)

    Dal Lago, A.; Antunes Vieira, L. E.; Echer, E.; Balmaceda, L. A.; Rockenbach, M.; Gonzalez, W. D.

    2017-10-01

    Extreme solar-terrestrial events are those in which very energetic solar ejections hit the earth?s magnetosphere, causing intense energization of the earth?s ring current. Statistically, their occurrence is approximately once per Gleissberg solar cycle (70-100yrs). The solar transient occurred on July, 23rd (2012) was potentially one of such extreme events. The associated coronal mass ejection (CME), however, was not ejected towards the earth. Instead, it hit the STEREO A spacecraft, located 120 degrees away from the Sun-Earth line. Estimates of the geoeffectiveness of such a CME point to a scenario of extreme Space Weather conditions. In terms of the ring current energization, as measured by the Disturbance Storm-Time index (Dst), had this CME hit the Earth, it would have caused the strongest geomagnetic storm in space era.

  7. Introduction to electronic analogue computers

    CERN Document Server

    Wass, C A A

    1965-01-01

    Introduction to Electronic Analogue Computers, Second Revised Edition is based on the ideas and experience of a group of workers at the Royal Aircraft Establishment, Farnborough, Hants. This edition is almost entirely the work of Mr. K. C. Garner, of the College of Aeronautics, Cranfield. As various advances have been made in the technology involving electronic analogue computers, this book presents discussions on the said progress, including some acquaintance with the capabilities of electronic circuits and equipment. This text also provides a mathematical background including simple differen

  8. Terrestrial Planet Finder Coronagraph High Accuracy Optical Propagation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Terrestrial Planet Finder (TPF) project is considering several approaches to discovering planets orbiting stars far from earth and assessing their suitability to...

  9. Terrestrial Planet Finder Coronagraph High Accuracy Optical Propagation, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Terrestrial Planet Finder (TPF) project is considering several approaches to discovering planets orbiting stars far from earth and assessing their suitability to...

  10. Electrochemical Power Plant for Terrestrial Flight Platforms, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An electrochemical power plant is proposed by MicroCell Technologies to provide power to terrestrial flight platforms. Our power plant is based upon a proton...

  11. NACP Site: Terrestrial Biosphere Model Output Data in Original Format

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set contains the original model output data submissions from the 24 terrestrial biosphere models (TBM) that participated in the North American...

  12. NACP Site: Terrestrial Biosphere Model Output Data in Original Format

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the original model output data submissions from the 24 terrestrial biosphere models (TBM) that participated in the North American Carbon...

  13. Between Analogue and Digital Diagrams

    Directory of Open Access Journals (Sweden)

    Zoltan Bun

    2012-10-01

    Full Text Available This essay is about the interstitial. About how the diagram, as a method of design, has lead fromthe analogue deconstruction of the eighties to the digital processes of the turn of the millennium.Specifically, the main topic of the text is the interpretation and the critique of folding (as a diagramin the beginning of the nineties. It is necessary then to unfold its relationship with immediatelypreceding and following architectural trends, that is to say we have to look both backwards andforwards by about a decade. The question is the context of folding, the exchange of the analogueworld for the digital. To understand the process it is easier to investigate from the fields of artand culture, rather than from the intentionally perplicated1 thoughts of Gilles Deleuze. Both fieldsare relevant here because they can similarly be used as the yardstick against which the era itselfit measured. The cultural scene of the eighties and nineties, including performing arts, movies,literature and philosophy, is a wide milieu of architecture. Architecture responds parallel to itsera; it reacts to it, and changes with it and within it. Architecture is a medium, it has always beena medium, yet the relations are transformed. That’s not to say that technical progress, for exampleusing CAD-software and CNC-s, has led to the digital thinking of certain movements ofarchitecture, (it is at most an indirect tool. But the ‘up-to-dateness’ of the discipline, however,a kind of non-servile reading of an ‘applied culture’ or ‘used philosophy’2 could be the key.(We might recall here, parenthetically, the fortunes of the artistic in contemporary mass society.The proliferation of museums, the magnification of the figure of the artist, the existence of amassive consumption of printed and televised artistic images, the widespread appetite for informationabout the arts, all reflect, of course, an increasingly leisured society, but also relateprecisely to the fact

  14. Superconductive analogue of spin glasses

    International Nuclear Information System (INIS)

    Feigel'man, M.; Ioffe, L.; Vinokur, V.; Larkin, A.

    1987-07-01

    The properties of granular superconductors in magnetic fields, namely the existence of a new superconductive state analogue of the low-temperature superconductive state in spin glasses are discussed in the frame of the infinite-range model and the finite-range models. Experiments for elucidation of spin-glass superconductive state in real systems are suggested. 30 refs

  15. PTH analogues and osteoporotic fractures

    NARCIS (Netherlands)

    Verhaar, H.J.; Lems, W.F.

    2010-01-01

    Importance of the field: At present there are two parathyroid hormone (PTH) analogues (PTH 1 34 and PTH 1 84) registered for the treatment of established osteoporosis in postmenopausal women (PTH 1 34 and PTH 1 84) and in men (PTH 1 34 only) who are at increased risk of having a fracture. Areas

  16. Chemopreventive properties of curcumin analogues ...

    African Journals Online (AJOL)

    Chemopreventive properties of curcumin analogues, hexagamavunone-0 and gamavutone-0, in rat colorectal cancer model. ... Histopathological analysis was performed using H & E staining and immunohistochemistry with antibodies against adenomatous polyposis coli (APC) and cyclooxygenase 2 (COX-2). Results: All ...

  17. Terrestrial Analogs to Mars

    Science.gov (United States)

    Farr, T. G.; Arcone, S.; Arvidson, R. W.; Baker, V.; Barlow, N. G.; Beaty, D.; Bell, M. S.; Blankenship, D. D.; Bridges, N.; Briggs, G.; Bulmer, M.; Carsey, F.; Clifford, S. M.; Craddock, R. A.; Dickerson, P. W.; Duxbury, N.; Galford, G. L.; Garvin, J.; Grant, J.; Green, J. R.; Gregg, T. K. P.; Guinness, E.; Hansen, V. L.; Hecht, M. H.; Holt, J.; Howard, A.; Keszthelyi, L. P.; Lee, P.; Lanagan, P. D.; Lentz, R. C. F.; Leverington, D. W.; Marinangeli, L.; Moersch, J. E.; Morris-Smith, P. A.; Mouginis-Mark, P.; Olhoeft, G. R.; Ori, G. G.; Paillou, P.; Reilly, J. F., II; Rice, J. W., Jr.; Robinson, C. A.; Sheridan, M.; Snook, K.; Thomson, B. J.; Watson, K.; Williams, K.; Yoshikawa, K.

    2002-08-01

    It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing. These studies include field workshops, characterization of terrestrial analog sites, instrument tests, laboratory measurements (including analysis of Martian meteorites), and computer and laboratory modeling. The combination of all these activities allows scientists to constrain the processes operating in specific terrestrial environments and extrapolate how similar processes could affect Mars. The Terrestrial Analogs for Mars Community Panel has considered the following two key questions: (1) How do terrestrial analog studies tie in to the Mars Exploration Payload Assessment Group science questions about life, past climate, and geologic evolution of Mars, and (2) How can future instrumentation be used to address these questions. The panel has considered the issues of data collection, value of field workshops, data archiving, laboratory measurements and modeling, human exploration issues, association with other areas of solar system exploration, and education and public outreach activities.

  18. Terrestrial Gravity Fluctuations

    Directory of Open Access Journals (Sweden)

    Jan Harms

    2015-12-01

    Full Text Available Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10^–23 Hz^–1/2 above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our

  19. Terrestrial Gravity Fluctuations

    Science.gov (United States)

    Harms, Jan

    2015-12-01

    Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW) detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10-23 Hz-1/2 above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of

  20. Terrestrial and extraterrestrial fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Heymann, D.; Jenneskens, L.W.; Jehlicka, J; Koper, C.; Vlietstra, E. [Rice Univ, Houston, TX (United States). Dept. of Earth Science

    2003-07-01

    This paper reviews reports of occurrences of fullerenes in circumstellar media, interstellar media, meteorites, interplanetary dust particles (IDPs), lunar rocks, hard terrestrial rocks from Shunga (Russia), Sudbury (Canada) and Mitov (Czech Republic), coal, terrestrial sediments from the Cretaceous-Tertiary-Boundary and Pennian-Triassic-Boundary, fulgurite, ink sticks, dinosaur eggs, and a tree char. The occurrences are discussed in the context of known and postulated processes of fullerene formation, including the suggestion that some natural fullerenes might have formed from biological (algal) remains.

  1. Sobolev spaces on graphs | Ostrovskii | Quaestiones Mathematicae

    African Journals Online (AJOL)

    The present paper is devoted to discrete analogues of Sobolev spaces of smooth functions. The discrete analogues that we consider are spaces of functions on vertex sets of graphs. Such spaces have applications in Graph Theory, Metric Geometry and Convex Geometry. We present known and prove some new results on ...

  2. The terrestrial silica pump.

    Directory of Open Access Journals (Sweden)

    Joanna C Carey

    Full Text Available Silicon (Si cycling controls atmospheric CO(2 concentrations and thus, the global climate, through three well-recognized means: chemical weathering of mineral silicates, occlusion of carbon (C to soil phytoliths, and the oceanic biological Si pump. In the latter, oceanic diatoms directly sequester 25.8 Gton C yr(-1, accounting for 43% of the total oceanic net primary production (NPP. However, another important link between C and Si cycling remains largely ignored, specifically the role of Si in terrestrial NPP. Here we show that 55% of terrestrial NPP (33 Gton C yr(-1 is due to active Si-accumulating vegetation, on par with the amount of C sequestered annually via marine diatoms. Our results suggest that similar to oceanic diatoms, the biological Si cycle of land plants also controls atmospheric CO(2 levels. In addition, we provide the first estimates of Si fixed in terrestrial vegetation by major global biome type, highlighting the ecosystems of most dynamic Si fixation. Projected global land use change will convert forests to agricultural lands, increasing the fixation of Si by land plants, and the magnitude of the terrestrial Si pump.

  3. Radionuclides in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Bocock, K.L.

    1981-01-01

    This report summarizes information on the distribution and movement of radionuclides in semi-natural terrestrial ecosystems in north-west England with particular emphasis on inputs to, and outputs from ecosystems; on plant and soil aspects; and on radionuclides in fallout and in discharges by the nuclear industry. (author)

  4. Histories of terrestrial planets

    International Nuclear Information System (INIS)

    Benes, K.

    1981-01-01

    The uneven historical development of terrestrial planets - Mercury, Venus, Earth, Moon and Mars - is probably due to the differences in their size, weight and rotational dynamics in association with the internal planet structure, their distance from the Sun, etc. A systematic study of extraterrestrial planets showed that the time span of internal activity was not the same for all bodies. It is assumed that the initial history of all terrestrial planets was marked with catastrophic events connected with the overall dynamic development of the solar system. In view of the fact that the cores of small terrestrial bodies cooled quicker, their geological development almost stagnated after two or three thousand million years. This is what probably happened to the Mercury and the Moon as well as the Mars. Therefore, traces of previous catastrophic events were preserved on the surface of the planets. On the other hand, the Earth is the most metamorphosed terrestrial planet and compared to the other planets appears to be atypical. Its biosphere is significantly developed as well as the other shell components, its hydrosphere and atmosphere, and its crust is considerably differentiated. (J.P.)

  5. Terrestrial planet formation.

    Science.gov (United States)

    Righter, K; O'Brien, D P

    2011-11-29

    Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (~10(6) y), followed by planetesimals to embryos (lunar to Mars-sized objects; few 10(6) y), and finally embryos to planets (10(7)-10(8) y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids.

  6. Novel acetylcholine and carbamoylcholine analogues

    DEFF Research Database (Denmark)

    Hansen, Camilla Petrycer; Jensen, Anders Asbjørn; Christensen, Jeppe K.

    2008-01-01

    A series of carbamoylcholine and acetylcholine analogues were synthesized and characterized pharmacologically at neuronal nicotinic acetylcholine receptors (nAChRs). Several of the compounds displayed low nanomolar binding affinities to the alpha 4beta 2 nAChR and pronounced selectivity...... for this subtype over alpha 3beta 4, alpha 4beta 4, and alpha 7 nAChRs. The high nAChR activity of carbamoylcholine analogue 5d was found to reside in its R-enantiomer, a characteristic most likely true for all other compounds in the series. Interestingly, the pronounced alpha 4beta 2 selectivities exhibited...... by some of the compounds in the binding assays translated into functional selectivity. Compound 5a was a fairly potent partial alpha 4beta 2 nAChR agonist with negligible activities at the alpha 3beta 4 and alpha 7 subtypes, thus being one of the few truly functionally selective alpha 4beta 2 nACh...

  7. Comparative Climatology of Terrestrial Planets

    Science.gov (United States)

    Mackwell, Stephen J.; Simon-Miller, Amy A.; Harder, Jerald W.; Bullock, Mark A.

    Public awareness of climate change on Earth is currently very high, promoting significant interest in atmospheric processes. We are fortunate to live in an era where it is possible to study the climates of many planets, including our own, using spacecraft and groundbased observations as well as advanced computational power that allows detailed modeling. Planetary atmospheric dynamics and structure are all governed by the same basic physics. Thus differences in the input variables (such as composition, internal structure, and solar radiation) among the known planets provide a broad suite of natural laboratory settings for gaining new understanding of these physical processes and their outcomes. Diverse planetary settings provide insightful comparisons to atmospheric processes and feedbacks on Earth, allowing a greater understanding of the driving forces and external influences on our own planetary climate. They also inform us in our search for habitable environments on planets orbiting distant stars, a topic that was a focus of Exoplanets, the preceding book in the University of Arizona Press Space Sciences Series. Quite naturally, and perhaps inevitably, our fascination with climate is largely driven toward investigating the interplay between the early development of life and the presence of a suitable planetary climate. Our understanding of how habitable planets come to be begins with the worlds closest to home. Venus, Earth, and Mars differ only modestly in their mass and distance from the Sun, yet their current climates could scarcely be more divergent. Our purpose for this book is to set forth the foundations for this emerging science and to bring to the forefront our current understanding of atmospheric formation and climate evolution. Although there is significant comparison to be made to atmospheric processes on nonterrestrial planets in our solar system — the gas and ice giants — here we focus on the terrestrial planets, leaving even broader comparisons

  8. Substrate analogues for isoprenoid enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Stremler, K.E.

    1987-01-01

    Diphosphonate analogues of geranyl diphosphate, resistant to degradation by phosphatases, were found to be alternate substrates for the reaction with farnesyl diphosphate synthetase isolated from avian liver. The difluoromethane analogue was shown to be the better alternate substrate, in agreement with solvolysis results which indicate that the electronegativity of the difluoromethylene unit more closely approximates that of the normal bridging oxygen. The usefulness of the C/sub 10/ difluoro analogue, for detecting low levels of isoprenoid enzymes in the presence of high levels of phosphatase activity, was demonstrated with a cell-free preparation from lemon peel. A series of C/sub 5/ through C/sub 15/ homoallylic and allylic diphosphonates, as well as two 5'-nucleotide diphosphonates, was prepared in high overall yield using the activation-displacement sequence. Radiolabeled samples of several of the allylic diphosphonates were prepared with tritium located at C1. A series of geraniols, stereospecifically deuterated at C1, was prepared. The enantiomeric purities and absolute configurations were determined by derivatization as the mandelate esters for analysis by /sup 1/H NMR. The stereochemistry of the activation-displacement sequence was examined using C1-deuterated substrates.

  9. Application of Terrestrial Environments in Orion Assessments

    Science.gov (United States)

    Barbre, Robert E.

    2016-01-01

    This presentation summarizes the Marshall Space Flight Center Natural Environments Terrestrial and Planetary Environments (TPE) Team support to the NASA Orion space vehicle. The TPE utilizes meteorological data to assess the sensitivities of the vehicle due to the terrestrial environment. The Orion vehicle, part of the Multi-Purpose Crew Vehicle Program, is designed to carry astronauts beyond low-earth orbit and is currently undergoing a series of tests including Exploration Test Flight (EFT) - 1. The presentation describes examples of TPE support for vehicle design and several tests, as well as support for EFT-1 and planning for upcoming Exploration Missions while emphasizing the importance of accounting for the natural environment's impact to the vehicle early in the vehicle's program.

  10. Interferometer Designs for the Terrestrial Planet Finder

    Science.gov (United States)

    Lawson, P. R.; Dumont, P. J.; Colavita, M. M.

    2000-01-01

    The Terrestrial Planet Finder (TPF) is a space-based infrared interferometer that will combine high sensitivity and spatial resolution to detect and characterize planetary systems within 15 pc of our sun. TPF is a key element in NASA's Origins Program and is currently un- der study in its Pre-Project Phase. We review some of the interferometer designs that have been considered for starlight nulling, with particular attention to the architecture and subsystems of the central beam-combiner.

  11. Working group 4: Terrestrial

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    A working group at a Canada/USA symposium on climate change and the Arctic identified major concerns and issues related to terrestrial resources. The group examined the need for, and the means of, involving resource managers and users at local and territorial levels in the process of identifying and examining the impacts and consequences of climatic change. Climatic change will be important to the Arctic because of the magnitude of the change projected for northern latitudes; the apparent sensitivity of its terrestrial ecosystems, natural resources, and human support systems; and the dependence of the social, cultural, and economic welfare of Arctic communities, businesses, and industries on the health and quality of their environment. Impacts of climatic change on the physical, biological, and associated socio-economic environment are outlined. Gaps in knowledge needed to quantify these impacts are listed along with their relationships with resource management. Finally, potential actions for response and adaptation are presented

  12. Phytopharmacology of Tribulus terrestris.

    Science.gov (United States)

    Shahid, M; Riaz, M; Talpur, M M A; Pirzada, T

    2016-01-01

    Tribulus terrestris is an annual herb which belongs to the Zygophyllaceae family. This plant has been used in traditional medicine for the treatment of various diseases for hundreds of decades. The main active phytoconstituents of this plant include flavonoids, alkaloids, saponins, lignin, amides, and glycosides. The plant parts have different pharmacological activities including aphrodisiac, antiinflammatory, antimicrobial and antioxidant potential. T. terrestris is most often used for infertility and loss of libido. It has potential application as immunomodulatory, hepatoprotective, hypolipidemic, anthelmintic and anticarcinogenic activities. The aim of the present article is to create a database for further investigation of the phytopharmacological properties of this plant to promote research. This study will definitely help to confirm its traditional use along with its value-added utility, eventually leading to higher revenues from the plant.

  13. Terrestrial plant methane production

    DEFF Research Database (Denmark)

    Mikkelsen, Teis Nørgaard; Bruhn, Dan; Møller, Ian M.

    We evaluate all experimental work published on the phenomenon of aerobic methane (CH4) generation in terrestrial plants. We conclude that the phenomenon is true. Four stimulating factors have been observed to induce aerobic plant CH4 production, i.e. cutting injuries, increasing temperature...... the aerobic methane emission in plants. Future work is needed for establishing the relative contribution of several proven potential CH4 precursors in plant material....

  14. Search Extra-Terrestrial of a civilization as a global problem of modernity: sociocultural of measurement

    OpenAIRE

    Щедрін, А. Т.

    2018-01-01

    In clause are considered evolution of a problem of life Extra-Terrestrial of reason in a context cultural practice of the past, its transformation in modern sociocultural space in a problem of life Extra-Terrestrial of civilizations. The bases of this process were spacing of culture of mankind, philosophy of Space. Consideration of space space as potential sphere creative of activity not only mankind, but also other social subjects having Extra-Terrestrial an origin and more a high level of d...

  15. Terrestrial Planet Formation Around Individual Stars Within Binary Star Systems

    OpenAIRE

    Quintana, Elisa V.; Adams, Fred C.; Lissauer, Jack J.; Chambers, John E.

    2007-01-01

    We calculate herein the late stages of terrestrial planet accumulation around a solar type star that has a binary companion with semimajor axis larger than the terrestrial planet region. We perform more than one hundred simulations to survey binary parameter space and to account for sensitive dependence on initial conditions in these dynamical systems. As expected, sufficiently wide binaries leave the planet formation process largely unaffected. As a rough approximation, binary stars with per...

  16. The Valles natural analogue project

    International Nuclear Information System (INIS)

    Stockman, H.; Krumhansl, J.; Ho, C.; McConnell, V.

    1994-12-01

    The contact between an obsidian flow and a steep-walled tuff canyon was examined as an analogue for a highlevel waste repository. The analogue site is located in the Valles Caldera in New Mexico, where a massive obsidian flow filled a paleocanyon in the Battleship Rock tuff. The obsidian flow provided a heat source, analogous to waste panels or an igneous intrusion in a repository, and caused evaporation and migration of water. The tuff and obsidian samples were analyzed for major and trace elements and mineralogy by INAA, XRF, X-ray diffraction; and scanning electron microscopy and electron microprobe. Samples were also analyzed for D/H and 39 Ar/ 4O isotopic composition. Overall,the effects of the heating event seem to have been slight and limited to the tuff nearest the contact. There is some evidence of devitrification and migration of volatiles in the tuff within 10 meters of the contact, but variations in major and trace element chemistry are small and difficult to distinguish from the natural (pre-heating) variability of the rocks

  17. Terrestrial Steering Group. 2014. Arctic Terrestrial Biodiversity Monitoring Plan

    DEFF Research Database (Denmark)

    Aastrup, Peter; Aronsson, Mora; Barry, Tom

    implementation of the Arctic Terrestrial Biodiversity Monitoring Plan for the next two years. Identify expert networks required for successful implementation of the plan. Identify key gaps and opportunities for the TSG related to plan implementation and identify near-term next steps to address gaps.......The Terrestrial Steering Group (TSG), has initiated the implementation phase of the CBMP Terrestrial Plan. The CBMP Terrestrial Steering Group, along with a set of invited experts (see Appendix A for a participants list), met in Iceland from February 25-27th to develop a three year work plan...... to guide implementation of the CBMP-Terrestrial Plan. This report describes the outcome of that workshop. The aim of the workshop was to develop a three year work plan to guide implementation of the CBMP-Terrestrial Plan. The participants were tasked with devising an approach to both (a) determine what...

  18. Arctic Terrestrial Biodiversity Monitoring Plan

    DEFF Research Database (Denmark)

    Christensen, Tom; Payne, J.; Doyle, M.

    The Conservation of Arctic Flora and Fauna (CAFF), the biodiversity working group of the Arctic Council, established the Circumpolar Biodiversity Monitoring Program (CBMP) to address the need for coordinated and standardized monitoring of Arctic environments. The CBMP includes an international...... on developing and implementing long-term plans for monitoring the integrity of Arctic biomes: terrestrial, marine, freshwater, and coastal (under development) environments. The CBMP Terrestrial Expert Monitoring Group (CBMP-TEMG) has developed the Arctic Terrestrial Biodiversity Monitoring Plan (CBMP......-Terrestrial Plan/the Plan) as the framework for coordinated, long-term Arctic terrestrial biodiversity monitoring. The goal of the CBMP-Terrestrial Plan is to improve the collective ability of Arctic traditional knowledge (TK) holders, northern communities, and scientists to detect, understand and report on long...

  19. Contaminant exposure in terrestrial vertebrates

    International Nuclear Information System (INIS)

    Smith, Philip N.; Cobb, George P.; Godard-Codding, Celine; Hoff, Dale; McMurry, Scott T.; Rainwater, Thomas R.; Reynolds, Kevin D.

    2007-01-01

    Here we review mechanisms and factors influencing contaminant exposure among terrestrial vertebrate wildlife. There exists a complex mixture of biotic and abiotic factors that dictate potential for contaminant exposure among terrestrial and semi-terrestrial vertebrates. Chemical fate and transport in the environment determine contaminant bioaccessibility. Species-specific natural history characteristics and behavioral traits then play significant roles in the likelihood that exposure pathways, from source to receptor, are complete. Detailed knowledge of natural history traits of receptors considered in conjunction with the knowledge of contaminant behavior and distribution on a site are critical when assessing and quantifying exposure. We review limitations in our understanding of elements of exposure and the unique aspects of exposure associated with terrestrial and semi-terrestrial taxa. We provide insight on taxa-specific traits that contribute, or limit exposure to, transport phenomenon that influence exposure throughout terrestrial systems, novel contaminants, bioavailability, exposure data analysis, and uncertainty associated with exposure in wildlife risk assessments. Lastly, we identify areas related to exposure among terrestrial and semi-terrestrial organisms that warrant additional research. - Both biotic and abiotic factors determine chemical exposure for terrestrial vertebrates

  20. Terrestrial Carbon Cycle Variability.

    Science.gov (United States)

    Baldocchi, Dennis; Ryu, Youngryel; Keenan, Trevor

    2016-01-01

    A growing literature is reporting on how the terrestrial carbon cycle is experiencing year-to-year variability because of climate anomalies and trends caused by global change. As CO 2 concentration records in the atmosphere exceed 50 years and as satellite records reach over 30 years in length, we are becoming better able to address carbon cycle variability and trends. Here we review how variable the carbon cycle is, how large the trends in its gross and net fluxes are, and how well the signal can be separated from noise. We explore mechanisms that explain year-to-year variability and trends by deconstructing the global carbon budget. The CO 2 concentration record is detecting a significant increase in the seasonal amplitude between 1958 and now. Inferential methods provide a variety of explanations for this result, but a conclusive attribution remains elusive. Scientists have reported that this trend is a consequence of the greening of the biosphere, stronger northern latitude photosynthesis, more photosynthesis by semi-arid ecosystems, agriculture and the green revolution, tropical temperature anomalies, or increased winter respiration. At the global scale, variability in the terrestrial carbon cycle can be due to changes in constituent fluxes, gross primary productivity, plant respiration and heterotrophic (microbial) respiration, and losses due to fire, land use change, soil erosion, or harvesting. It remains controversial whether or not there is a significant trend in global primary productivity (due to rising CO 2 , temperature, nitrogen deposition, changing land use, and preponderance of wet and dry regions). The degree to which year-to-year variability in temperature and precipitation anomalies affect global primary productivity also remains uncertain. For perspective, interannual variability in global gross primary productivity is relatively small (on the order of 2 Pg-C y -1 ) with respect to a large and uncertain background (123 +/- 4 Pg-C y -1 ), and

  1. Terrestrial case studies of ilmenite exploration and lunar implications

    Science.gov (United States)

    Feldman, S. C.; Franklin, H. A.

    1993-03-01

    The Space Exploration Initiative (SEI) includes space resource utilization as one of the four architectures to achieve U.S. goals in space. Space resource utilization will make use of lunar resources to support long term activities on the lunar surface. Lunar ilmenite and regolith are two of the materials that can be mined and processed for lunar oxygen production. During this investigation, several sources were reviewed to assess terrestrial exploration methods used for locating ilmenite resources. These sources included published reports on terrestrial ilmenite exploration methods, analytical methods, case histories, chemical and physical properties, and associations with other minerals. Using a terrestrial analog and considering the differences between terrestrial and lunar environmental conditions, rocks, and minerals, exploration methods and analytical instruments can be recommended for a lunar orbiter and lander for assessing lunar resources. Twelve terrestrial case histories were reviewed to gain insight into ilmenite exploration on the Moon. All exploration case histories follow the same pattern. They begin with a model, use remote geophysical techniques, define regional sampling sites from the model and geophysics, narrow down the area of exploration based on the preceding work, collect more samples and cores, and perform laboratory analyses of samples. An important part of this process is the collection of samples to determine the correctness of the model. Surface and core samples are collected in areas expected to contain both high and low concentration of the commodity to test the model. After samples are analyzed and the area of mineralization is defined, reserves are calculated to determine the cost/benefit ratio, the necessary capacity of the processing plant, and the life of the mine. The exploration methods used for locating terrestrial ilmenite resources are reviewed with respect to the petrology, chemistry, and mineral associations of the

  2. French radioactive wastes performance assessment and the natural analogues approach: an overview

    International Nuclear Information System (INIS)

    Escalier des Orres, P.

    1988-10-01

    One of the main difficulties linked to the Radioactive Waste Performance Assessment calculations lies in the scale of time and space underlying these calculations: mechanisms and parameters can directly be affected by time or space dependency. The ''natural analogues'' approach has evident advantages, at least qualitative, to enlighten these aspects. It may also provide confidence in our ability to model partial or overall natural systems. The following paper gives the headlines of the use of the ''natural analogues'' methodology in the French Radioactive Wastes Performance Assessment in the field of waste disposal

  3. On the Use of the Analogue Transformation Acoustics in Aeroacoustics

    Directory of Open Access Journals (Sweden)

    Umberto Iemma

    2017-01-01

    Full Text Available The objective of the paper is the assessment of the Analogue Transformation Acoustics (ATA in the design of acoustic metamaterial for aeronautical applications. The work focuses on the consistency of the background flow resulting from the application of the ATA with the equations governing the potential aerodynamics. Indeed, in case of acoustic perturbations propagating within moving media, the convective terms in the governing equations are responsible for the failure of formal invariance under the action of conformal mappings. The ATA approach overcomes this limitation, introducing the possibility of handling the convective form of the wave equation in a straightforward and elegant way. It is based on the concept of analogue space-time and fully relies on the analytical tools of Lorentzian differential geometry. The present paper analyses the relationship between the analogue velocity field with a realistic potential flow. The method is validated through numerical simulations using two widely assessed acoustic cloaking problems. The preliminary results obtained show that the use of numerical, quasi-conformal mappings can lead to transformed streamlines negligibly deviating from those of the potential velocity field satisfying the fluid-dynamic conservation laws, but with incompatible intensity of the local velocity.

  4. Condensed matter analogues of cosmology

    Science.gov (United States)

    Kibble, Tom; Srivastava, Ajit

    2013-10-01

    It is always exciting when developments in one branch of physics turn out to have relevance in a quite different branch. It would be hard to find two branches farther apart in terms of energy scales than early-universe cosmology and low-temperature condensed matter physics. Nevertheless ideas about the formation of topological defects during rapid phase transitions that originated in the context of the very early universe have proved remarkably fruitful when applied to a variety of condensed matter systems. The mathematical frameworks for describing these systems can be very similar. This interconnection has led to a deeper understanding of the phenomena in condensed matter systems utilizing ideas from cosmology. At the same time, one can view these condensed matter analogues as providing, at least in a limited sense, experimental access to the phenomena of the early universe for which no direct probe is possible. As this special issue well illustrates, this remains a dynamic and exciting field. The basic idea is that when a system goes through a rapid symmetry-breaking phase transition from a symmetric phase into one with spontaneously broken symmetry, the order parameter may make different choices in different regions, creating domains that when they meet can trap defects. The scale of those domains, and hence the density of defects, is constrained by the rate at which the system goes through the transition and the speed with which order parameter information propagates. This is what has come to be known as the Kibble-Zurek mechanism. The resultant scaling laws have now been tested in a considerable variety of different systems. The earliest experiments illustrating the analogy between cosmology and condensed matter were in liquid crystals, in particular on the isotropic-to-nematic transition, primarily because it is very easy to induce the phase transition (typically at room temperature) and to image precisely what is going on. This field remains one of the

  5. Antimicrobial Activity of Resveratrol Analogues

    Directory of Open Access Journals (Sweden)

    Malik Chalal

    2014-06-01

    Full Text Available Stilbenes, especially resveratrol and its derivatives, have become famous for their positive effects on a wide range of medical disorders, as indicated by a huge number of published studies. A less investigated area of research is their antimicrobial properties. A series of 13 trans-resveratrol analogues was synthesized via Wittig or Heck reactions, and their antimicrobial activity assessed on two different grapevine pathogens responsible for severe diseases in the vineyard. The entire series, together with resveratrol, was first evaluated on the zoospore mobility and sporulation level of Plasmopara viticola (the oomycete responsible for downy mildew. Stilbenes displayed a spectrum of activity ranging from low to high. Six of them, including the most active ones, were subsequently tested on the development of Botrytis cinerea (fungus responsible for grey mold. The results obtained allowed us to identify the most active stilbenes against both grapevine pathogens, to compare the antimicrobial activity of the evaluated series of stilbenes, and to discuss the relationship between their chemical structure (number and position of methoxy and hydroxy groups and antimicrobial activity.

  6. A low-dimensional analogue of holographic baryons

    Science.gov (United States)

    Bolognesi, Stefano; Sutcliffe, Paul

    2014-04-01

    Baryons in holographic QCD correspond to topological solitons in the bulk. The most prominent example is the Sakai-Sugimoto model, where the bulk soliton in the five-dimensional spacetime of AdS-type can be approximated by the flat space self-dual Yang-Mills instanton with a small size. Recently, the validity of this approximation has been verified by comparison with the numerical field theory solution. However, multi-solitons and solitons with finite density are currently beyond numerical field theory computations. Various approximations have been applied to investigate these important issues and have led to proposals for finite density configurations that include dyonic salt and baryonic popcorn. Here we introduce and investigate a low-dimensional analogue of the Sakai-Sugimoto model, in which the bulk soliton can be approximated by a flat space sigma model instanton. The bulk theory is a baby Skyrme model in a three-dimensional spacetime with negative curvature. The advantage of the lower-dimensional theory is that numerical simulations of multi-solitons and finite density solutions can be performed and compared with flat space instanton approximations. In particular, analogues of dyonic salt and baryonic popcorn configurations are found and analysed.

  7. Terrestrial forest management plan for Palmyra Atoll

    Science.gov (United States)

    Hathaway, Stacie A.; McEachern, Kathryn; Fisher, Robert N.

    2011-01-01

    , and though rarely documented, beach nesting could be affected by terrestrial management actions. There are various nonnative or invasive species throughout the terrestrial ecosystem. The most notable examples of terrestrial invasive species include coconut palms (Cocos nucifera) and black rats (Rattus rattus). Although it is unclear whether they are nonnative, coconut palms are currently the most dominant plant across Palmyra Atoll. They compete with native plant species for space and resources and are potentially detrimental to sea birds dependent on native vegetation for roosting and nesting habitat. This competition in turn impacts nutrient resource availability, thereby reshaping energy flow in the ecosystem. Black rats are known to prey on ground-nesting sea birds and are likely responsible for the lack of burrowing sea bird reproduction at Palmyra Atoll. In addition, they may be facilitating the invasion of other nonnative species and negatively impacting other native fauna. Although the extent and impacts of these and other nonnative and (or) invasive species are not fully understood, the extent and impacts are clearly a threat to the native species and one of the most urgent threats to the overall ecosystem integrity of Palmyra Atoll. This 'Terrestrial Forest Management Plan for Palmyra Atoll' addresses issues related to invasive species and other problems. Priority goals are established as are associated objectives and strategies. The overarching goal is to perpetuate and where possible restore terrestrial ecosystem integrity through the following techniques: 1. Habitat management: Maintain and enhance habitat to the extent possible to sustain thriving Pisonia grandis forest, coastal strand forest, endemic grassland, self-sustaining populations of sea birds, shore birds, coconut crabs, native lizards, and native insects. 2. Monitoring and assessment: Acquire information on distribution and abundance as needed for conservation of each resour

  8. Ecological transfer mechanisms - Terrestrial

    International Nuclear Information System (INIS)

    Martin, W.E.; Raines, Gilbert E.; Bloom, S.G.; Levin, A.A.

    1969-01-01

    Radionuclides produced by nuclear excavation detonations and released to the environment may enter a variety of biogeochemical cycles and follow essentially the same transfer pathways as their stable-element counterparts. Estimation of potential internal radiation doses to individuals and/or populations living in or near fallout-contaminated areas requires analysis of the food-chain and other ecological pathways by which radionuclides released to the environment may be returned to man. A generalized materials transfer diagram, applicable to the forest, agricultural, freshwater and marine ecosystems providing food and water to the indigenous population of Panama and Colombia in regions that could be affected by nuclear excavation of a sea-level canal between the Atlantic and Pacific Oceans, is presented. Transfer mechanisms effecting the movement of stable elements and radionuclides in terrestrial ecosystems are discussed, and methods used to simulate these processes by means of mathematical models are described to show how intake values are calculated for different radionuclides in the major ecological pathways leading to man. These data provide a basis for estimating potential internal radiation doses for comparison with the radiation protection criteria established by recognized authorities; and this, in turn, provides a basis for recommending measures to insure the radiological safety of the nuclear operation plan. (author)

  9. Immediate, non-submerged, root-analogue zirconia implant in single tooth replacement.

    Science.gov (United States)

    Pirker, W; Kocher, A

    2008-03-01

    This report demonstrates the successful clinical use of a modified root-analogue zirconia implant for immediate single tooth replacement. A right maxillary premolar was removed and a custom-made, root-analogue, roughened zirconia implant with macro-retentions in the interdental space was fabricated and placed into the extraction socket 4 days later. Four months after root implantation a composite crown was cemented. No complications occurred during the healing period. An excellent esthetic and functional result was achieved with the composite crown. No clinically noticeable bone resorption or soft-tissue recession was observed at 26 months follow up. Significant modifications such as macro-retentions seem to indicate that primary stability and excellent osseointegration of immediate root-analogue zirconia implants can be achieved, while preventing unesthetic bone resorption. The macro-retentions must be limited to the interdental space to avoid fracture of the thin buccal cortex. This successful case warrants further clinical research in well controlled trials.

  10. An arsenical analogue of adenosine diphosphate.

    Science.gov (United States)

    Webster, D; Sparkes, M J; Dixon, H B

    1978-01-01

    An analogue of ADP was made in which the terminal phosphono-oxy group, -O-PO(OH)2, has been replaced by the arsonomethyl group, -CH2-AsO(OH)2. This compound cannot form a stable analogue of ATP because anhydrides of arsonic acids are rapidly hydrolysed, so that any enzyme that phosphorylates ADP and accepts this analogue as a substrate should release orthophosphate in its presence. The analogue proves to be a poor substrate for 3-phosphoglycerate kinase (V/Km is diminished by a factor of 10(2)-10(3)) and a very poor substrate for pyruvate kinase (V/Km is diminished by a factor of 10(5)-10(6)). No substrate action was detected with adenyl kinase and creatine kinase. PMID:204292

  11. International video project on natural analogues

    International Nuclear Information System (INIS)

    Guentensperger, Marcel

    1993-01-01

    A natural analogue can be defined as a natural process which has occurred in the past and is studied in order to test predictions about the future evolution of similar processes. In recent years, natural analogues have been used increasingly to test the mathematical models required for repository performance assessment. Analogues are, however, also of considerable use in public relations as they allow many of the principles involved in demonstrating repository safety to be illustrated in a clear manner using natural systems with which man is familiar. The international Natural Analogue Working Group (NAWG), organised under the auspices of the CEC, has recognised that such PR applications are of considerable importance and should be supported from a technical level. At the NAWG meeting in Pitlochry, Scotland (June 1990), it was recommended that the possibilities for making a video film on this topic be investigated and Nagra was requested to take the lead role in setting up such a project

  12. Natural analogues and radionuclide transport model validation

    International Nuclear Information System (INIS)

    Lever, D.A.

    1987-08-01

    In this paper, some possible roles for natural analogues are discussed from the point of view of those involved with the development of mathematical models for radionuclide transport and with the use of these models in repository safety assessments. The characteristic features of a safety assessment are outlined in order to address the questions of where natural analogues can be used to improve our understanding of the processes involved and where they can assist in validating the models that are used. Natural analogues have the potential to provide useful information about some critical processes, especially long-term chemical processes and migration rates. There is likely to be considerable uncertainty and ambiguity associated with the interpretation of natural analogues, and thus it is their general features which should be emphasized, and models with appropriate levels of sophistication should be used. Experience gained in modelling the Koongarra uranium deposit in northern Australia is drawn upon. (author)

  13. Volcanic lake systems as terrestrial analogue for sulphate-rich terrains on Mars

    NARCIS (Netherlands)

    Rodríguez, A.

    2016-01-01

    Remote-sensing observations and rover missions have documented the abundant presence of sulphate-rich mineral associations on the surface of Mars. Together with widespread occurrences of silica and frequent enrichments of chlorine and bromine in soils and rocks, the sulphate associations are

  14. Hybrid Processing Combining Electrostatic Levitation and Laser Heating: Application to Terrestrial Analogues of Asteroid Materials

    Directory of Open Access Journals (Sweden)

    Paul-François Paradis

    2011-01-01

    Full Text Available Electrostatic levitation combined with laser heating is becoming a mature technique that has been used for several fundamental and applied studies in fluid and materials sciences (synthesis, property determination, solidification studies, atomic dynamic studies, etc.. This is attributable to the numerous processing conditions (containerless, wide heating temperature range, cooling rates, atmospheric compositions, etc. that levitation and radiative heating offer, as well as to the variety of diagnostics tools that can be used. In this paper, we describe the facility, highlighting the combined advantages of electrostatic levitation and laser processing. The various capabilities of the facility are discussed and are exemplified with the measurements of the density of selected iron-nickel alloys taken over the liquid phase.

  15. Río Tinto : A geochemical and mineralogical terrestrial analogue of Mars

    NARCIS (Netherlands)

    Amils, Ricardo; Fernández-Remolar, David; Parro, Victor; Rodríguez-Manfredi, José Antonio; Oggerin, Monike; Sánchez-Román, Mónica; López, Francisco J.; Fernández-Rodríguez, José Pablo; Puente-Sánchez, Fernando; Briones, Carlos; Prieto-Ballesteros, Olga; Tornos, Fernando; Gómez, Felipe; García-Villadangos, Miriam; Rodríguez, Nuria; Omoregie, Enoma; Timmis, Kenneth; Arce, Alejandro; Sanz, José Luis; Gómez-Ortiz, David

    2014-01-01

    The geomicrobiological characterization of the water column and sediments of Río Tinto (Huelva, Southwestern Spain) have proven the importance of the iron and the sulfur cycles, not only in generating the extreme conditions of the habitat (low pH, high concentration of toxic heavy metals), but also

  16. Space Commercialization

    Science.gov (United States)

    Martin, Gary L.

    2011-01-01

    A robust and competitive commercial space sector is vital to continued progress in space. The United States is committed to encouraging and facilitating the growth of a U.S. commercial space sector that supports U.S. needs, is globally competitive, and advances U.S. leadership in the generation of new markets and innovation-driven entrepreneurship. Energize competitive domestic industries to participate in global markets and advance the development of: satellite manufacturing; satellite-based services; space launch; terrestrial applications; and increased entrepreneurship. Purchase and use commercial space capabilities and services to the maximum practical extent Actively explore the use of inventive, nontraditional arrangements for acquiring commercial space goods and services to meet United States Government requirements, including measures such as public-private partnerships, . Refrain from conducting United States Government space activities that preclude, discourage, or compete with U.S. commercial space activities. Pursue potential opportunities for transferring routine, operational space functions to the commercial space sector where beneficial and cost-effective.

  17. Space space space

    CERN Document Server

    Trembach, Vera

    2014-01-01

    Space is an introduction to the mysteries of the Universe. Included are Task Cards for independent learning, Journal Word Cards for creative writing, and Hands-On Activities for reinforcing skills in Math and Language Arts. Space is a perfect introduction to further research of the Solar System.

  18. DAS photonics developments for analogue and digital photonic links for intra-satellite communications

    Science.gov (United States)

    Blasco, Julián.; Rico, Eloy; Genovard, Pablo; Sáez, Cristina; Navasquillo, Olga; Martí, Javier

    2017-11-01

    During past years, special efforts have been invested to develop optical links, both digital and analogue, for space applications, such as reference signal distribution or digital communication cables. The aim of this paper is to present the current DAS developments for these applications as well as future work to increase TRL levels and flight opportunities.

  19. Perspectives on Human Attachment (Pair Bonding: Eve's Unique Legacy of a Canine Analogue

    Directory of Open Access Journals (Sweden)

    Ronald S. Immerman

    2003-01-01

    Full Text Available The mother-child bond is undoubtedly homologous with that of other primates (and mammals. However, the man-woman pair bond and man(tochild pair bond are not paralleled by any terrestrial primate nor many mammals. Hence, knowledge of primate behavior would not be predictive of the pan-human (i social father and (ii the extended pair bond between a man and woman (with the cultural overlay of marriage. It is suggested that female choice of mating partner shifted in the direction of a canid analogue in which men's motivations to share resources with the female and to exhibit paternalistic behaviors were positively selected. Accordingly, it would be predicted that, compared to other terrestrial primates, the neuro-hormonal bases for the mother-child affiliative bond would be similar, but the bases of man-woman affiliative bond and the man(tochild affiliative bond would be dissimilar.

  20. Classical analogue of an interstellar travel through a hydrodynamic wormhole

    Science.gov (United States)

    Euvé, L.-P.; Rousseaux, G.

    2017-09-01

    The classical theory of space-time, namely general relativity, suggests but does not demonstrate the existence of so-called wormholes allowing for interstellar journeys. Alternative proposals such as quantum gravity theories are developed nowadays to allow for wormhole travels by assuming hypothetical trans-Planckian effects at tiny scales. Here we show experimentally that analogue traversable and bidirectional wormholes exist in hydrodynamics following a suggestion by Wheeler. Using a water channel, we sent free surface waves on a countercurrent in an analogue gravity setup aiming at showing that hydrodynamic wormhole travels are controlled by a cascade of dispersive scales including surface tension effects: the capillary wavelength plays the role of a Planckian scale below which long gravity waves are transformed into short capillary waves that are able to move at speeds higher than the "flow" of space-time. Whereas our results do not apply to putative astrophysical wormholes per se, we anticipate that they will trigger new ideas to explore quantum gravity physics.

  1. Biome-BGC: Terrestrial Ecosystem Process Model, Version 4.1.1

    Data.gov (United States)

    National Aeronautics and Space Administration — Biome-BGC is a computer program that estimates fluxes and storage of energy, water, carbon, and nitrogen for the vegetation and soil components of terrestrial...

  2. Low Earth Orbit satellite/terrestrial mobile service compatibility

    Science.gov (United States)

    Sheriff, Ray E.; Gardiner, John G.

    1993-01-01

    Currently the geostationary type of satellite is the only one used to provide commercial mobile-satellite communication services. Low earth orbit (LEO) satellite systems are now being proposed as a future alternative. By the implementation of LEO satellite systems, predicted at between 5 and 8 years time, mobile space/terrestrial technology will have progressed to the third generation stage of development. This paper considers the system issues that will need to be addressed when developing a dual mode terminal, enabling access to both terrestrial and LEO satellite systems.

  3. Geological trainings for analogue astronauts: Lessons learned from MARS2013 expedition, Morocco

    Science.gov (United States)

    Orgel, C.; Achorner, I.; Losiak, A.; Gołębiowska, I.; Rampey, M.; Groemer, G.

    2013-09-01

    The Austrian Space Forum (OeWF) is a national organisation for space professionals and space enthusiasts. In collaboration with internal partner organisations, the OeWF focuses on Mars analogue research with their space volunteers and organises space-related outreach/education activities and conducts field tests with the Aouda.X and Aouda.S spacesuit simulators in Mars analogue environment. The main project of OeWF is called "PolAres" [1]. As the result of lessons learned from the Río Tinto 2011 expedition [4], we started to organise geological training sessions for the analogue astronauts. The idea was to give them basic geological background to perform more efficiently in the field. This was done in close imitation of the Apollo astronaut trainings that included theoretical lectures (between Jan. 1963-Nov. 1972) about impact geology, igneous petrology of the Moon, geophysics and geochemistry as well as several field trips to make them capable to collect useful samples for the geoscientists on Earth [3] [5]. In the last year the OeWF has organised three geoscience workshops for analogue astronauts as the part of their "astronaut" training. The aim was to educate the participants to make them understand the fundamentals in geology in theory and in the field (Fig. 1.). We proposed the "Geological Experiment Sampling Usefulness" (GESU) experiment for the MARS2013 simulation to improve the efficiency of the geological trainings. This simulation was conducted during February 2013, a one month Mars analogue research was conducted in the desert of Morocco [2] (Fig. 2.).

  4. On an analogue of Hardy's inequality for the Walsh-Fourier

    International Nuclear Information System (INIS)

    Golubov, B I

    2001-01-01

    According to Hardy's well-known inequality, the l 1 -norm of a function in the Hardy space H(t) consisting of 2π-periodic functions serves as an upper estimate for the l 1 -norm of the sequence of Fourier coefficients of the integral of the function. In this paper, the dyadic Hardy space H(R + ) is introduced and an analogue of this estimate is proved for the Walsh-Fourier transform

  5. Synthesis and anticancer evaluation of spermatinamine analogues

    KAUST Repository

    Moosa, Basem

    2016-02-04

    Spermatinamine was isolated from an Australian marine sponge, Pseudoceratina sp. as an inhibitor of isoprenylcystiene carboxyl methyltransferase (Icmt), an attractive and novel anticancer target. Herein, we report the synthesis of spermatinamine analogues and their cytotoxic evaluation against three human cancer cell lines i.e. cervix adenocarcinoma (HeLa), breast adenocarcinoma (MCF-7), and prostate carcinoma (DU145). Analogues 12, 14 and 15 were found to be the most potent against one or more cell lines with the IC50 values in the range of 5 - 10 μM. The obtained results suggested that longer polyamine linker along with aromatic oxime substitution provided the most potent analogue compounds against cancer cell lines.

  6. NASA HRP Immunology Discipline - Use of Terrestrial Analogs

    Science.gov (United States)

    Crucian, Brian

    2014-01-01

    Due to the cost and operational constraints, as well as technical implementation limitations, it is desirous to perform relevant space physiology investigations first in terrestrial 'space analogs'. This is particularly true for initial investigations, which may then provide appropriate focus for subsequent flight investigations, or for mechanistic investigations that simply cannot be performed during spaceflight. Appropriate analog choice is extremely important. There are a wide variety of terrestrial space analogs, each relevant to a particular physiological discipline (or disciplines) and each with a particular fidelity (or lack thereof) to spaceflight, and each with unique operational constraints. The HRP Immunology Discipline is tasked with managing the HRP Risk concerning clinical risk for Astronaut crews related to spaceflight-associated immune dysregulation. Such dysregulation has been documented to occur during spaceflight, and found to persist for the duration of a 6-month ISS mission. Studies continue to characterize the onorbit phenomenon, but it generally consists of diminished immunocyte function, dysregulated cytokine profiles, and persistent herpesvirus reactivation. Causes are thought to synergistically include microgravity, psychological or physiological stress, radiation, and/or circadian misalignment. An appropriate terrestrial analog for immune dysregulation would replicate as many of these influences as possible. Such analogs may include clinostat or bioreactor cell culture (microgravity), hindlimb suspension (stress, fluid shifts, hypokinesis), or human deployment to remote or extreme environments (isolation, stress, circadian). Also, the laboratory setting may be used as an analog, or to augment analogs, such as sleep deprivation/misalignment or human centrifugation to replicate gravitational stress. As an appropriate example of a NASA Disciplines use of Terrestrial space analogs, this talk will discuss spaceflight associated immune

  7. Design Of Robots For Outer Space

    Science.gov (United States)

    Roston, Gerald P.

    1990-01-01

    Report discusses design of robots for use in zero gravity and vacuum, with attention to differences between requirements imposed on designs by outer space and by terrestrial applications. Terrestrial robots designed for multiple purposes and for minimal cost. Outer-space robots designed specialized to one task where cost has relatively low priority. Design optimal in one environment unlikely optimal in another.

  8. Nontoxic piperamides and their synthetic analogues as novel antifouling reagents

    KAUST Repository

    Huang, Xiang-Zhong

    2014-03-25

    Bioassay-guided isolation of an acetone extract from a terrestrial plant Piper betle produced four known piperamides with potent antifouling (AF) activities, as evidenced by inhibition of settlement of barnacle cypris larvae. The AF activities of the four piperamides and 15 synthesized analogues were compared and their structure-activity relationships were probed. Among the compounds, piperoleine B and 1-[1-oxo-7-(3′,4′-methylenedioxyphenyl)-6E-heptenyl]-piperidine (MPHP) showed strong activity against settlement of cyprids of the barnacle Balanus amphitrite, having EC50 values of 1.1 ± 0.3 and 0.5 ± 0.2 μg ml-1, respectively. No toxicity against zebra fish was observed following incubation with these two compounds. Besides being non-toxic, 91% of piperoleine B-treated cyprids and 84% of MPHP-treated cyprids at a concentration of 100 μM completed normal metamorphosis in recovery bioassays, indicating that the anti-settlement effect of these two compounds was reversible. Hydrolysis and photolysis experiments indicated that MPHP could be decomposed in the marine environment. It is concluded that piperamides are promising compounds for use in marine AF coatings. © 2014 © 2014 Taylor & Francis.

  9. Soil and terrestrial biology studies

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Soil and terrestrial biology studies focused on developing an understanding of the uptake of gaseous substances from the atmosphere by plants, biodegradation of oil, and the movement of Pu in the terrestrial ecosystems of the southeastern United States. Mathematical models were developed for SO 2 and tritium uptake from the atmosphere by plants; the uptake of tritium by soil microorganisms was measured; and the relationships among the Pu content of soil, plants, and animals of the Savannah River Plant area were studied. Preliminary results are reported for studies on the biodegradation of waste oil on soil surfaces

  10. Priapism caused by 'Tribulus terrestris'.

    Science.gov (United States)

    Campanelli, M; De Thomasis, R; Tenaglia, R L

    2016-01-01

    A 36-year-old Caucasian man was diagnosed with a 72-h-lasting priapism that occurred after the assumption of a Herbal supplement based on Tribulus terrestris, which is becoming increasingly popular for the treatment of sexual dysfunction. The patient underwent a cavernoglandular shunt (Ebbehoj shunt) in order to obtain complete detumescence, from which derived negative post-episode outcomes on sexual function. All patients consuming non-FDA-approved alternative supplements such as Tribulus terrestris should be warned about the possible serious side effects.

  11. Water vapor estimation using digital terrestrial broadcasting waves

    Science.gov (United States)

    Kawamura, S.; Ohta, H.; Hanado, H.; Yamamoto, M. K.; Shiga, N.; Kido, K.; Yasuda, S.; Goto, T.; Ichikawa, R.; Amagai, J.; Imamura, K.; Fujieda, M.; Iwai, H.; Sugitani, S.; Iguchi, T.

    2017-03-01

    A method of estimating water vapor (propagation delay due to water vapor) using digital terrestrial broadcasting waves is proposed. Our target is to improve the accuracy of numerical weather forecast for severe weather phenomena such as localized heavy rainstorms in urban areas through data assimilation. In this method, we estimate water vapor near a ground surface from the propagation delay of digital terrestrial broadcasting waves. A real-time delay measurement system with a software-defined radio technique is developed and tested. The data obtained using digital terrestrial broadcasting waves show good agreement with those obtained by ground-based meteorological observation. The main features of this observation are, no need for transmitters (receiving only), applicable wherever digital terrestrial broadcasting is available and its high time resolution. This study shows a possibility to estimate water vapor using digital terrestrial broadcasting waves. In the future, we will investigate the impact of these data toward numerical weather forecast through data assimilation. Developing a system that monitors water vapor near the ground surface with time and space resolutions of 30 s and several kilometers would improve the accuracy of the numerical weather forecast of localized severe weather phenomena.

  12. Analogue alternative the electronic analogue computer in Britain and the USA, 1930-1975

    CERN Document Server

    Small, James S

    2013-01-01

    We are in the midst of a digital revolution - until recently, the majority of appliances used in everyday life have been developed with analogue technology. Now, either at home or out and about, we are surrounded by digital technology such as digital 'film', audio systems, computers and telephones. From the late 1940s until the 1970s, analogue technology was a genuine alternative to digital, and the two competing technologies ran parallel with each other. During this period, a community of engineers, scientists, academics and businessmen continued to develop and promote the analogue computer.

  13. A Bosonic Analogue of a Topological Dirac Semi-Metal

    Science.gov (United States)

    Lapa, Matthew; Cho, Gil Young; Hughes, Taylor

    We construct a bosonic analogue of a two-dimensional topological Dirac Semi-Metal (DSM). The low-energy description of the most basic 2D DSM model consists of two Dirac cones at positions +/-k0 in momentum space. The local stability of the Dirac cones is guaranteed by a composite symmetry Z2, where  is time-reversal and  is inversion. This model also exhibits interesting time-reversal and inversion symmetry breaking electromagnetic responses. In this work we construct a bosonic analogue of a DSM by replacing each Dirac cone with a copy of the O (4) Nonlinear Sigma Model (NLSM) with topological theta term and theta angle θ = +/- π . One copy of this NLSM also describes the gapless surface termination of the 3D Bosonic Topological Insulator (BTI). We compute the time-reversal and inversion symmetry breaking electromagnetic responses for our model and show that they are twice the value one gets in the DSM case. We also investigate the local stability of the individual O (4) NLSM's in the BSM model. Along the way we clarify many aspects of the surface theory of the BTI including the electromagnetic response, the charges of vortex excitations, and the stability to symmetry-allowed perturbations. Nsf CAREER DMR-1351895.

  14. Total synthesis of sannanine and analogues thereof

    Indian Academy of Sciences (India)

    BADHER NAVEEN

    2018-03-02

    Mar 2, 2018 ... concise manner. The key strategies involve Friedländer quinoline synthesis, demethylation, in situ oxidation and amination process. ..... (b) Hargreaves R, David C L, Whitesell L and Skibo E. B 2003 Design of Quinolinedione-Based Geldanamycin. Analogues Bioorg. Med. Chem. Lett. 13 3075; (c) Arg-.

  15. Ultrasound exfoliation of inorganic analogues of graphene

    Czech Academy of Sciences Publication Activity Database

    Štengl, Václav; Henych, Jiří; Slušná, Michaela; Ecorchard, Petra

    2014-01-01

    Roč. 9, APR (2014), s. 1-14 ISSN 1556-276X R&D Projects: GA ČR(CZ) GA14-05146S Institutional support: RVO:61388980 Keywords : Ultrasound * Exfoliation * Graphene inorganic analogues Subject RIV: CA - Inorganic Chemistry Impact factor: 2.779, year: 2014

  16. The World Is either Digital or Analogue

    NARCIS (Netherlands)

    Berto, F.; Tagliabue, J.

    2014-01-01

    We address an argument by Floridi (Synthese 168(1):151-178, 2009; 2011a), to the effect that digital and analogue are not features of reality, only of modes of presentation of reality. One can therefore have an informational ontology, like Floridi’s Informational Structural Realism, without

  17. Somatostatin analogue scintigraphy and tuberculosis: case report

    International Nuclear Information System (INIS)

    Biancheri, I.; Rudenko, B.; Vautrin, P.; Raddoul, J.; Lamfichek, N.; Kantelip, B.; Mantion, G.

    2005-01-01

    Scintigraphy using a radiolabelled somatostatin analogue (111 In-pentetreotide) is useful in the detection of neuroendocrine tumors. But this radiopharmaceutical accumulates also in solid tumours or in inflammatory diseases such as granulomatosis. We present a case of 111 In-pentetreotide uptake in a tuberculous adenopathy. (author)

  18. Prussian Blue Analogues of Reduced Dimensionality

    NARCIS (Netherlands)

    Gengler, Regis Y. N.; Toma, Luminita M.; Pardo, Emilio; Lloret, Francesc; Ke, Xiaoxing; Van Tendeloo, Gustaaf; Gournis, Dimitrios; Rudolf, Petra

    2012-01-01

    Mixed-valence polycyanides (Prussian Blue analogues) possess a rich palette of properties spanning from room-temperature ferromagnetism to zero thermal expansion, which can be tuned by chemical modifications or the application of external stimuli (temperature, pressure, light irradiation). While

  19. The Palmottu analogue project: overview for 1993

    International Nuclear Information System (INIS)

    Ruskeeniemi, T.; Blomqvist, R.; Suksi, J.; Niini, H.

    1994-01-01

    This article gives a summary of the activities carried out within the Palmottu analogue project in 1993. It consists of (1) an introductory part, followed by (2) a geological description of the site, and (3)an up-to-date summary of the results of the project. (orig.) (33 refs., 6 figs.)

  20. Terrestrial ecosystems and their change

    Science.gov (United States)

    Anatoly Z. Shvidenko; Eric Gustafson; A. David McGuire; Vjacheslav I. Kharuk; Dmitry G. Schepaschenko; Herman H. Shugart; Nadezhda M. Tchebakova; Natalia N. Vygodskaya; Alexander A. Onuchin; Daniel J. Hayes; Ian McCallum; Shamil Maksyutov; Ludmila V. Mukhortova; Amber J. Soja; Luca Belelli-Marchesini; Julia A. Kurbatova; Alexander V. Oltchev; Elena I. Parfenova; Jacquelyn K. Shuman

    2012-01-01

    This chapter considers the current state of Siberian terrestrial ecosystems, their spatial distribution, and major biometric characteristics. Ongoing climate change and the dramatic increase of accompanying anthropogenic pressure provide different but mostly negative impacts on Siberian ecosystems. Future climates of the region may lead to substantial drying on large...

  1. Provenance of the terrestrial planets.

    Science.gov (United States)

    Wetherill, G W

    1994-01-01

    Earlier work on the simultaneous accumulation of the asteroid belt and the terrestrial planets is extended to investigate the relative contribution to the final planets made by material from different heliocentric distances. As before, stochastic variations intrinsic to the accumulation processes lead to a variety of final planetary configurations, but include systems having a number of features similar to our solar system. Fifty-nine new simulations are presented, from which thirteen are selected as more similar to our solar system than the others. It is found that the concept of "local feeding zones" for each final terrestrial planet has no validity for this model. Instead, the final terrestrial planets receive major contributions from bodies ranging from 0.5 to at least 2.5 AU, and often to greater distances. Nevertheless, there is a correlation between the final heliocentric distance of a planet and its average provenance. Together with the effect of stochastic fluctuations, this permits variation in the composition of the terrestrial planets, such as the difference in the decompressed density of Earth and Mars. Biologically important light elements, derived from the asteroidal region, are likely to have been significant constituents of the Earth during its formation.

  2. Aquatic and Terrestrial Environment 2004

    DEFF Research Database (Denmark)

    Andersen, J. M.; Boutrup, S.; Bijl, L. van der

    , watercourses, lakes and marine waters and the pressures upon them and reviews the monitoring of terrestrial natural habitats and selected plants and animals. The report is based on the annual reports prepared for each subprogramme by the Topic Centres. The latter reports are mainly based on data collected...

  3. Geology and Habitability of Terrestrial Planets

    CERN Document Server

    Fishbaugh, Kathryn E; Raulin, François; Marais, David J; Korablev, Oleg

    2007-01-01

    Given the fundamental importance of and universal interest in whether extraterrestrial life has developed or could eventually develop in our solar system and beyond, it is vital that an examination of planetary habitability goes beyond simple assumptions such as, "Where there is water, there is life." This book has resulted from a workshop at the International Space Science Institute (ISSI) in Bern, Switzerland (5-9 September 2005) that brought together planetary geologists, geophysicists, atmospheric scientists, and biologists to discuss the multi-faceted problem of how the habitability of a planet co-evolves with the geology of the surface and interior, the atmosphere, and the magnetosphere. Each of the six chapters has been written by authors with a range of expertise so that each chapter is itself multi-disciplinary, comprehensive, and accessible to scientists in all disciplines. These chapters delve into what life needs to exist and ultimately to thrive, the early environments of the young terrestrial pl...

  4. Quantitative comparisons of analogue models of brittle wedge dynamics

    Science.gov (United States)

    Schreurs, Guido

    2010-05-01

    , models accommodated initial shortening by a forward- and a backward-verging thrust. Further shortening was taken up by in-sequence formation of forward-verging thrusts. In all experiments, boundary stresses created significant drag of structures along the sidewalls. We therefore compared the surface slope and the location, dip angle and spacing of thrusts in sections through the central part of the model. All models show very similar cross-sectional evolutions demonstrating reproducibility of first-order experimental observations. Nevertheless, there are significant along-strike variations of structures in map view highlighting the limits of interpretations of analogue model results. These variations may be related to the human factor, differences in model width and/or differences in laboratory temperature and especially humidity affecting the mechanical properties of the granular materials. GeoMod2008 Analogue Team: Susanne Buiter, Caroline Burberry, Jean-Paul Callot, Cristian Cavozzi, Mariano Cerca, Ernesto Cristallini, Alexander Cruden, Jian-Hong Chen, Leonardo Cruz, Jean-Marc Daniel, Victor H. Garcia, Caroline Gomes, Céline Grall, Cecilia Guzmán, Triyani Nur Hidayah, George Hilley, Chia-Yu Lu, Matthias Klinkmüller, Hemin Koyi, Jenny Macauley, Bertrand Maillot, Catherine Meriaux, Faramarz Nilfouroushan, Chang-Chih Pan, Daniel Pillot, Rodrigo Portillo, Matthias Rosenau, Wouter P. Schellart, Roy Schlische, Andy Take, Bruno Vendeville, Matteo Vettori, M. Vergnaud, Shih-Hsien Wang, Martha Withjack, Daniel Yagupsky, Yasuhiro Yamada

  5. Natural product analogues: towards a blueprint for analogue-focused synthesis.

    Science.gov (United States)

    Bebbington, Magnus W P

    2017-08-14

    For the first time a general overview of approaches to the synthesis of natural product analogues is presented. This reflects a process of evolution of natural product synthesis which has accelerated in the years since the implementation of diversity-oriented synthesis, which has emerged in parallel with collective synthesis, diverted total synthesis and the preparation of truncated natural products optimised for biological activity. A method involving computational assessment for the validation of core-modified natural product analogues is discussed.

  6. Human factors research as part of a Mars exploration analogue mission on Devon Island

    Science.gov (United States)

    Binsted, Kim; Kobrick, Ryan L.; Griofa, Marc Ó.; Bishop, Sheryl; Lapierre, Judith

    2010-06-01

    Human factors research is a critical element of space exploration as it provides insight into a crew's performance, psychology and interpersonal relationships. Understanding the way humans work in space-exploration analogue environments permits the development and testing of countermeasures for and responses to potential hazardous situations, and can thus help improve mission efficiency and safety. Analogue missions, such as the one described here, have plausible mission constraints and operational scenarios, similar to those that a real Mars crew would experience. Long duration analogue studies, such as those being conducted at the Flashline Mars Arctic Research Station (FMARS) on Devon Island, Canada, offer an opportunity to study mission operations and human factors in a semi-realistic environment, and contribute to the design of missions to explore the Moon and Mars. The FMARS XI Long Duration Mission (F-XI LDM) was, at four months, the longest designed analogue Mars mission conducted to date, and thus provides a unique insight into human factors issues for long-duration space exploration. Here, we describe the six human factors studies that took place during F-XI LDM, and give a summary of their results, where available. We also present a meta-study, which examined the impact of the human-factors research itself on crew schedule and workload. Based on this experience, we offer some lessons learnt: some aspects (perceived risk and crew motivation, for example) of analogue missions must be realistic for study results to be valid; human factors studies are time-consuming, and should be fully integrated into crew schedules; and crew-ground communication and collaboration under long-term exploration conditions can present serious challenges.

  7. Tryptophan analogues. 1. Synthesis and antihypertensive activity of positional isomers.

    Science.gov (United States)

    Safdy, M E; Kurchacova, E; Schut, R N; Vidrio, H; Hong, E

    1982-06-01

    A series of tryptophan analogues having the carboxyl function at the beta-position was synthesized and tested for antihypertensive activity. The 5-methoxy analogue 46 exhibited antihypertensive activity in the rat via the oral route and was much more potent than the normal tryptophan analogue. The methyl ester was found to be a critical structural feature for activity.

  8. Space dosimetry

    International Nuclear Information System (INIS)

    Doke, Tadayoshi

    1988-01-01

    Japan will take part in the LML-1 (International Microgravity Laboratory 1) program that is scheduled to be carried out with space shuttles to be launched in 1991. The program will be followed by the LS-J (Space Laboratory-Japan) and IML-2 programs. A reliable dosimetry system is currently required to be established to evaluate the radiations in space. The present article reviews major features of different types of space radiations and requirements of dosimeters for these radiations. The radiations in the space environment consist of: 1) electrons and protons that have been trapped by the terrestrial magnetism, 2) corpuscular, gamma-and X-rays released from the sun, and 3) galactic cosmic rays (corpuscular, gamma-and X-rays). The effects of the trapped radiations will be low if a spacecraft can get through the zone of such radiations in a short period of time. The effects of galactic cosmic rays are much smaller than those of the trapped radiations. A solar flare can give significant contributions to the total radiations received by a spacecraft. An extremely large flare can release a fatal amount of radiations to the crew of a spacecraft. Prediction of such a large flare is of great important for a long trip through the space. Significant improvements should be made on existing dosimeters. (Nogami, K.)

  9. Strategy for the Explorer program for solar and space physics

    International Nuclear Information System (INIS)

    1984-01-01

    Contents include: executive summary; the Explorer program - background and current status; strategy - level of activity; solar-terrestrial research (solar physics, space plasma physics, and upper atmospheric physics)

  10. Mars : a small terrestrial planet

    OpenAIRE

    Mangold, N.; Baratoux, David; Witasse, O.; Encrenaz, T.; Sotin, C.

    2016-01-01

    Mars is characterized by geological landforms familiar to terrestrial geologists. It has a tenuous atmosphere that evolved differently from that of Earth and Venus and a differentiated inner structure. Our knowledge of the structure and evolution of Mars has strongly improved thanks to a huge amount of data of various types (visible and infrared imagery, altimetry, radar, chemistry, etc) acquired by a dozen of missions over the last two decades. In situ data have provided ground truth for rem...

  11. Somatostatin analogues for acute bleeding oesophageal varices

    DEFF Research Database (Denmark)

    Gøtzsche, Peter C.; Hrobjartsson, A.

    2008-01-01

    BACKGROUND: Somatostatin and its derivatives are sometimes used for emergency treatment of bleeding oesophageal varices in patients with cirrhosis of the liver. OBJECTIVES: To study whether somatostatin or its analogues improve survival or reduce the need for blood transfusions in patients...... with bleeding oesophageal varices. SEARCH STRATEGY: PubMed and The Cochrane Library were searched (November 2007). Reference lists of publications, contacts with authors. SELECTION CRITERIA: All randomised trials comparing somatostatin or analogues with placebo or no treatment in patients suspected of acute...... or recent bleeding from oesophageal varices. DATA COLLECTION AND ANALYSIS: The outcome measures extracted were: mortality, blood transfusions, use of balloon tamponade, initial haemostasis and rebleeding. Intention-to-treat analyses including all randomised patients were conducted if possible; a random...

  12. Studies of natural analogues and geological systems

    International Nuclear Information System (INIS)

    Brandberg, F.; Grundfelt, B.; Hoeglund, L.; Skagius K.; Karlsson, F.; Smellie, J.

    1993-04-01

    This review has involved studies of natural analogues and natural geological systems leading to the identification and quantification of processes and features of importance to the performance and safety of repositories for radioactive waste. The features and processes selected for the study comprise general geochemical issues related to the performance of the near- and far-field, the performance and durability of construction materials and the effects of glaciation. For each of these areas a number of potentially important processes for repository performance have been described, and evidence for their existence, as well as quantification of parameters of models describing the processes have been sought from major natural analogue studies and site investigations. The review has aimed at covering a relatively broad range of issues at the expense of in-depth analysis. The quantitative data presented are in most cases compilations of data from the literature; in a few cases results of evaluations made within the current project are included

  13. Boron hydride analogues of the fullerenes

    International Nuclear Information System (INIS)

    Quong, A.A.; Pederson, M.R.; Broughton, J.Q.

    1994-01-01

    The BH moiety is isoelectronic with C. We have studied the stability of the (BH) 60 analogue of the C 60 fullerene as well as the dual-structure (BH) 32 icosahedron, both of them being putative structures, by performing local-density-functional electronic calculations. To aid in our analysis, we have also studied other homologues of these systems. We find that the latter, i.e., the dual structure, is the more stable although the former is as stable as one of the latter's lower homologues. Boron hydrides, it seems, naturally form the dual structures used in algorithmic optimization of complex fullerene systems. Fully relaxed geometries are reported as well as electron affinities and effective Hubbard U parameters. These systems form very stable anions and we conclude that a search for BH analogues of the C 60 alkali-metal supeconductors might prove very fruitful

  14. The synthesis and pharmacology of ephedrine analogues

    OpenAIRE

    Mullen, Aidan J

    1991-01-01

    In this report we set out to extend recent studies on substituted PAC analogues produced by the fermentation of aromatic aldehydes with Saccharomyces cerevisiae. The medium selected contained glucose as a carbon source for the biotransformation, and sodium pyruvate as an inhibitor for alcohol dehydrogenase, the enzyme responsible for the conversion of the carbinol to a benzyl alcohol derivatives. An investigation of sodium cyanoborohydride for a selective reductive ami...

  15. Electromagnetic wave analogue of electronic diode

    OpenAIRE

    Shadrivov, Ilya V.; Powell, David A.; Kivshar, Yuri S.; Fedotov, Vassili A.; Zheludev, Nikolay I.

    2010-01-01

    An electronic diode is a nonlinear semiconductor circuit component that allows conduction of electrical current in one direction only. A component with similar functionality for electromagnetic waves, an electromagnetic isolator, is based on the Faraday effect of the polarization state rotation and is also a key component of optical and microwave systems. Here we demonstrate a chiral electromagnetic diode, which is a direct analogue of an electronic diode: its functionality is underpinned by ...

  16. Geometric Analogue of Holographic Reduced Representation

    OpenAIRE

    Aerts, Diederik; Czachor, Marek; De Moor, Bart

    2007-01-01

    Holographic reduced representations (HRR) are based on superpositions of convolution-bound $n$-tuples, but the $n$-tuples cannot be regarded as vectors since the formalism is basis dependent. This is why HRR cannot be associated with geometric structures. Replacing convolutions by geometric products one arrives at reduced representations analogous to HRR but interpretable in terms of geometry. Variable bindings occurring in both HRR and its geometric analogue mathematically correspond to two ...

  17. Analogue forecasting of New Zealand climate anomalies

    Science.gov (United States)

    Mullan, A. Brett; Thompson, Craig S.

    2006-03-01

    An analogue forecast scheme is described for multifield prediction of monthly and seasonal New Zealand climate anomalies on the basis of the methodology of Livezey and Barnston ([1988]) for US seasonal temperatures. The method is applied to predicting terciles of temperature and precipitation for six regions of New Zealand. Empirical orthogonal function analysis is used to reduce sea surface temperature and sea-level pressure predictors down to a set of five independent indices, which incorporate variations due to El Niño-Southern Oscillation, Indian Ocean sea temperatures and a wave 3 pattern in the Southern Hemisphere westerlies. A full bootstrap cross-validation procedure is carried out, along with Monte Carlo tests, to assess the skill of the method on independent data and to determine the significance of the results. Significant skill is found for seasonal temperature forecasts for the summer and winter seasons; there is less success in predicting monthly temperatures or rainfall at either timescale. Considerable care is required to constrain the climate state vector, from which analogues are defined, and to constrain the search procedure itself, in order to produce results that are stable with respect to small parameter changes in the model. For the New Zealand region, 5 to 7 is found to be the optimum number of closest analogues, and the inclusion of anti-analogues improves the predictions, at least in the seasonal case. Skill in predicting regional temperature and rainfall is shown to be related to a combination of skill in predicting sea-level pressure patterns and to how strongly these patterns project onto temperature and rainfall anomalies.

  18. The Brookhaven electron analogue, 1953--1957

    International Nuclear Information System (INIS)

    Plotkin, M.

    1991-01-01

    The following topics are discussed on the Brookhaven electron analogue: L.J. Haworth and E.L. VanHorn letters; Original G.K. Green outline for report; General description; Parameter list; Mechanical Assembly; Alignment; Degaussing; Vacuum System; Injection System; The pulsed inflector; RF System; Ferrite Cavity; Pick-up electrodes and preamplifiers; Radio Frequency power amplifier; Lens supply; Controls and Power; and RF acceleration summary

  19. The Brookhaven electron analogue, 1953--1957

    Energy Technology Data Exchange (ETDEWEB)

    Plotkin, M.

    1991-12-18

    The following topics are discussed on the Brookhaven electron analogue: L.J. Haworth and E.L. VanHorn letters; Original G.K. Green outline for report; General description; Parameter list; Mechanical Assembly; Alignment; Degaussing; Vacuum System; Injection System; The pulsed inflector; RF System; Ferrite Cavity; Pick-up electrodes and preamplifiers; Radio Frequency power amplifier; Lens supply; Controls and Power; and RF acceleration summary.

  20. Synthesis of D-nor steroid analogues

    Czech Academy of Sciences Publication Activity Database

    Slavíková, Barbora; Kudová, Eva

    2014-01-01

    Roč. 108, S2 (2014), s142 ISSN 0009-2770. [Conference on Isoprenoids /22./. 07.09.2014-10.09.2014, Praha] R&D Projects: GA TA ČR(CZ) TE01020028; GA ČR(CZ) GAP303/12/1464 Institutional support: RVO:61388963 Keywords : D-nor steroid analogues * patch clamp technique Subject RIV: CC - Organic Chemistry

  1. New alloferon analogues: synthesis and antiviral properties.

    Science.gov (United States)

    Kuczer, Mariola; Majewska, Anna; Zahorska, Renata

    2013-02-01

    We have extended our study on structure/activity relationship studies of insect peptide alloferon (H-His-Gly-Val-Ser-Gly-His-Gly-Gln-His-Gly-Val-His-Gly-OH) by evaluating the antiviral effects of new alloferon analogues. We synthesized 18 alloferon analogues: 12 peptides with sequences shortened from N- or C-terminus and 6 N-terminally modified analogues H-X(1)-Gly-Val-Ser-Gly-His-Gly-Gln-His-Gly-Val-His-Gly-OH, where X(1) = Phe (13), Tyr (14), Trp (15), Phg (16), Phe(p-Cl) (17), and Phe(p-OMe) (18). We found that most of the evaluated peptides inhibit the replication of Human Herpesviruses or Coxsackievirus B2 in Vero, HEp-2 and LLC-MK(2) cells. Our results indicate that the compound [3-13]-alloferon (1) exhibits the strongest antiviral activity (IC(50) = 38 μM) among the analyzed compound. Moreover, no cytotoxic activity against the investigated cell lines was observed for all studied peptides at concentration 165 μM or higher. © 2012 John Wiley & Sons A/S.

  2. Synthetic spectra of simulated terrestrial atmospheres containing possible biomarker gases.

    Science.gov (United States)

    Schindler, T L; Kasting, J F

    2000-05-01

    NASA's proposed Terrestrial Planet Finder, a space-based interferometer, will eventually allow spectroscopic analyses of the atmospheres of extrasolar planets. Such analyses would provide information about the existence of life on these planets. One strategy in the search for life is to look for evidence of O3 (and hence O2) in a planet's atmosphere; another is to look for gases that might be present in an atmosphere analogous to that of the inhabited early Earth. In order to investigate these possibilities, we have calculated synthetic spectra for several hypothetical terrestrial-type atmospheres. The model atmospheres represent four different scenarios. The first two, representing inhabited terrestrial planets, are an Earth-like atmosphere containing variable amounts of oxygen and an early Earth-type atmosphere containing methane. In addition, two cases representing Mars-like and early Venus-like atmospheres were evaluated, to provide possible "false positive" spectra. The calculated spectra suggest that ozone could be detected by an instrument like Terrestrial Planet Finder if the O2 concentration in the planet's atmosphere is > or = 200 ppm, or 10(-3) times the present atmospheric level. Methane should be observable on an early-Earth type planet if it is present in concentrations of 100 ppm or more. Methane has both biogenic and abiogenic sources, but concentrations exceeding 1000 ppm, or 0.1% by volume, would be difficult to produce from abiogenic sources alone. High methane concentrations in a planet's atmosphere are therefore another potential indicator for extraterrestrial life.

  3. SAR mapping of Burfellshraun: A terrestrial analog for recent volcanism on Mars

    DEFF Research Database (Denmark)

    Haack, Henning; Rossi, Matti; Dall, Jørgen

    2006-01-01

    between 10 and 100 Myr. Parts of the lava flows show smooth kilometer-sized plates that appear to have rafted on the moving lava flow. We have found a terrestrial analogue with similar features, the Burfellshraun lava flow in Northern Iceland. This is the only known lava flow on Earth where kilometer......-sized rafting plates are observed and constitute the dominating feature. Using a combination of airborne remote sensing data and field observations we have studied the emplacement and physical properties of the flow. On the basis of our observations we have reconstructed the sequence of events that led...

  4. Analogue to Digital and Digital to Analogue Converters (ADCs and DACs): A Review Update

    CERN Document Server

    Pickering, J.

    2015-06-15

    This is a review paper updated from that presented for CAS 2004. Essentially, since then, commercial components have continued to extend their performance boundaries but the basic building blocks and the techniques for choosing the best device and implementing it in a design have not changed. Analogue to digital and digital to analogue converters are crucial components in the continued drive to replace analogue circuitry with more controllable and less costly digital processing. This paper discusses the technologies available to perform in the likely measurement and control applications that arise within accelerators. It covers much of the terminology and 'specmanship' together with an application-oriented analysis of the realisable performance of the various types. Finally, some hints and warnings on system integration problems are given.

  5. Space technology needs nuclear power

    International Nuclear Information System (INIS)

    Leidinger, B.J.G.

    1993-01-01

    Space technology needs nuclear power to solve its future problems. Manned space flight to Mars is hardly feasible without nuclear propulsion, and orbital nuclear power lants will be necessary to supply power to large satellites or large space stations. Nuclear power also needs space technology. A nuclear power plant sited on the moon is not going to upset anybody, because of the high natural background radiation level existing there, and could contribute to terrestrial power supply. (orig./HP) [de

  6. Space weather: European Space Agency perspectives

    Science.gov (United States)

    Daly, E. J.; Hilgers, A.

    Spacecraft and payloads have become steadily more sophisticated and therefore more susceptible to space weather effects. ESA has long been active in applying models and tools to the problems associated with such effects on its spacecraft. In parallel, ESA and European agencies have built a highly successful solar-terrestrial physics capability. ESA is now investigating the marriage of these technological and scientific capabilities to address perceived user needs for space weather products and services. Two major ESA-sponsored studies are laying the groundwork for a possible operational European space weather service. The wide-ranging activities of ESA in the Space Weather/Space Environment domain are summarized and recent important examples of space weather concerns given.

  7. Terrestrial ecosystems under warmer and drier climates

    Science.gov (United States)

    Pan, Y.

    2016-12-01

    Future warmer and drier climates will likely affect many of the world's terrestrial ecosystems. These changes will fundamentally reshape terrestrial systems through their components and across organization levels. However, it is unclear to what extent terrestrial ecosystems would be resilient enough to stay put to increased temperature and water stress by only adjusting carbon fluxes and water balances? And to what extent it would reach the thresholds at which terrestrial ecosystems were forced to alter species compositions and ecosystem structures for adapting to newer climates? The energy balance of terrestrial ecosystems link thermal and water conditions to defines terrestrial carbon processes and feedbacks to climate, which will inevitably change under warmer and drier climates. Recent theoretical studies provide a new framework, suggesting that terrestrial ecosystems were capable of balancing costs of carbon gain and water transport to achieve optimums for functioning and distribution. Such a paradigm is critical for understanding the dynamics of future terrestrial ecosystems under climate changes, and facilitate modeling terrestrial ecosystems which needs generalized principles for formulating ecosystem behaviors. This study aims to review some recent studies that explore responses of terrestrial ecosystems to rather novel climate conditions, such as heat-induced droughts, intending to provide better comprehension of complex carbon-water interactions through plants to an ecosystem, and relevant factors that may alleviate or worsen already deteriorated climates such as elevated CO2 and soil conditions.

  8. Introduction to Space Resource Mining

    Science.gov (United States)

    Mueller, Robert P.

    2013-01-01

    There are vast amounts of resources in the solar system that will be useful to humans in space and possibly on Earth. None of these resources can be exploited without the first necessary step of extra-terrestrial mining. The necessary technologies for tele-robotic and autonomous mining have not matured sufficiently yet. The current state of technology was assessed for terrestrial and extraterrestrial mining and a taxonomy of robotic space mining mechanisms was presented which was based on current existing prototypes. Terrestrial and extra-terrestrial mining methods and technologies are on the cusp of massive changes towards automation and autonomy for economic and safety reasons. It is highly likely that these industries will benefit from mutual cooperation and technology transfer.

  9. State selective reactions of cosmic dust analogues at cryogenic temperatures

    International Nuclear Information System (INIS)

    Perry, James Samuel Anthony

    2001-01-01

    Molecular hydrogen (H 2 ) is the most abundant molecule in interstellar space. It is crucial for initiating all of the chemistry in the Interstellar Medium (ISM) and consequently plays an important role in star formation. However, the amount of H 2 believed to exist in the ISM cannot be accounted for by formation through gas-phase reactions alone. The current, widely accepted theory, is that H 2 forms on the surface of cosmic dust grains. These grains are thought to be composed of amorphous forms of carbon or silicates with temperatures of around 10 K. This thesis describes a new experiment that has been constructed to study H 2 formation on the surface of cosmic dust analogues and presents the initial experimental results. The experiment simulates, through ultra-high vacuum and the use of cryogenics, the conditions of the ISM where cosmic dust grains and H 2 molecules exist. During the experiment, a beam of atomic hydrogen is aimed at a cosmic dust analogue target. H 2 formed on the target's surface is ionised using a laser spectroscopy technique known as Resonance Enhanced Multiphoton lonisation (REMPI) and detected using time-of-flight mass spectrometry. The sensitivity of REMPI is such that H 2 molecules can be ionised in selective internal energy states. This allows the rovibrational populations of the H 2 molecules desorbing from the cosmic dust targets to be determined, providing information on the energy budget of the H 2 formation process in the ISM. Preliminary results from the experiment show that H 2 molecules formed on a diamond-like-carbon surface have a significant non-thermal population of excited vibrational and rotational energy states. (author)

  10. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2014-01-01

    Terrestrial water storage (TWS) comprises groundwater, soil moisture, surface water, snow,and ice. Groundwater typically varies more slowly than the other TWS components because itis not in direct contact with the atmosphere, but often it has a larger range of variability onmultiannual timescales (Rodell and Famiglietti, 2001; Alley et al., 2002). In situ groundwaterdata are only archived and made available by a few countries. However, monthly TWSvariations observed by the Gravity Recovery and Climate Experiment (GRACE; Tapley et al.,2004) satellite mission, which launched in 2002, are a reasonable proxy for unconfinedgroundwater at climatic scales.

  11. ADS-B in space

    DEFF Research Database (Denmark)

    Knudsen, Bjarke Gosvig; Jensen, Morten; Birklykke, Alex

    2014-01-01

    them to the terrestrial receivers. This paper gives an overview of the GATOSS mission and of its highly-sensitive ADS-B software-defined radio receiver payload. Details of the design and implementation of the receiver's decoder are introduced. The first real-life, space-based results show that ADS......-B signals are indeed successfully received in space and retransmitted to a terrestrial station by the GATOSS nano-satellite orbiting at 700+ km altitudes, thus showing that GATOSS is capable of tracking flights, including transoceanic ones, from space....

  12. The Greenland analogue project. Yearly report 2010

    International Nuclear Information System (INIS)

    Harper, J.; Brinkerhoff, D.; Johnson, J.; Ruskeeniemi, T.; Engstroem, J.; Kukkonen, I.

    2012-04-01

    A four-year field and modelling study of the Greenland ice sheet and subsurface conditions, Greenland Analogue Project (GAP), has been initiated collaboratively by SKB, Posiva and NWMO to advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository. The study site encompasses a land terminus portion of the Greenland ice sheet, east of Kangerlussuaq, and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project begins in 2009 and is scheduled for completion in 2012. Our current understanding of the hydrological, hydrogeological and hydrogeochemical processes associated with cold climate conditions and glacial cycles, and their impact on the long-term performance of deep geological repositories for spent nuclear fuel, will be significantly improved by studying a modern analogue. The GAP will conduct the first in situ investigations of some of the parameters and processes needed to achieve a better understanding of how an ice sheet may impact a deep repository, and will provide measurements, observations and data that may significantly improve our safety assessments and risk analyses of glaciation scenarios. This report was produced by the GAP team members and presents an overview of the activities within the GAP during the interval January 1 to December 31, 2010, as well as research results obtained during this time frame. Research for the GAP is ongoing, and additional results related to the data presented here may become available in the future and will be presented in subsequent annual reports. (orig.)

  13. The Greenland analogue project. Yearly report 2010

    Energy Technology Data Exchange (ETDEWEB)

    Harper, J.; Brinkerhoff, D.; Johnson, J. [University of Montana, Missoula (United States); Ruskeeniemi, T.; Engstroem, J.; Kukkonen, I. [Geological Survey of Finland (Finland)] [and others

    2012-04-15

    A four-year field and modelling study of the Greenland ice sheet and subsurface conditions, Greenland Analogue Project (GAP), has been initiated collaboratively by SKB, Posiva and NWMO to advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository. The study site encompasses a land terminus portion of the Greenland ice sheet, east of Kangerlussuaq, and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project begins in 2009 and is scheduled for completion in 2012. Our current understanding of the hydrological, hydrogeological and hydrogeochemical processes associated with cold climate conditions and glacial cycles, and their impact on the long-term performance of deep geological repositories for spent nuclear fuel, will be significantly improved by studying a modern analogue. The GAP will conduct the first in situ investigations of some of the parameters and processes needed to achieve a better understanding of how an ice sheet may impact a deep repository, and will provide measurements, observations and data that may significantly improve our safety assessments and risk analyses of glaciation scenarios. This report was produced by the GAP team members and presents an overview of the activities within the GAP during the interval January 1 to December 31, 2010, as well as research results obtained during this time frame. Research for the GAP is ongoing, and additional results related to the data presented here may become available in the future and will be presented in subsequent annual reports. (orig.)

  14. Natural Analogues of CO2 Geological Storage

    International Nuclear Information System (INIS)

    Perez del Villar, L.; Pelayo, M.; Recreo, F.

    2007-01-01

    Geological storage of carbon dioxide is nowadays, internationally considered as the most effective method for greenhouse gas emission mitigation, in order to minimize the global climate change universally accepted. Nevertheless, the possible risks derived of this long-term storage have a direct influence on its public acceptance. Among the favourable geological formations to store CO2, depleted oil and gas fields, deep saline reservoirs, and unamiable coal seams are highlighted. One of the most important objectives of the R and D projects related to the CO2 geological storage is the evaluation of the CO2 leakage rate through the above mentioned geological formations. Therefore, it is absolutely necessary to increase our knowledge on the interaction among CO2, storage and sealing formations, as well as on the flow paths and the physical resistance of the sealing formation. The quantification of the CO2 leakage rate is essential to evaluate the effects on the human and animal health, as well as for the ecosystem and water quality. To achieve these objectives, the study of the natural analogues is very useful in order to know the natural leakage rate to the atmosphere, its flow paths, the physical, chemical and mineralogical modifications due to the long term interaction processes among the CO2 and the storage and sealing formations, as well as the effects on the groundwaters and ecosystems. In this report, we have tried to summarise the main characteristics of the natural reservoirs and surficial sources of CO2, which are both natural analogues of the geological storage and CO2 leakage, studied in EEUU, Europe and Australia. The main objective of this summary is to find the possible applications for long-term risk prediction and for the performance assessment by means of conceptual and numerical modelling, which will allow to validate the predictive models of the CO2 storage behaviour, to design and develop suitable monitoring techniques to control the CO2 behaviour

  15. Nuclear waste geochemistry: natural and anthropic analogues

    International Nuclear Information System (INIS)

    Petit, J.C.

    1997-01-01

    The geochemical evolution of nuclear waste storage is difficult to describe, due to the long time scales involved, the radioactivity confinement complexity and the un-natural radionuclides which evolution is not known. In order to carry out a long term prediction, a special approach is used, based on a combination of experiments conducted in laboratories and in situ, modelizations and comparisons with process and material analogues (natural or man-made, such as basaltic and rhyolitic volcanic glasses, plutonium, historical and archaeological artefacts)

  16. Somatostatin analogue scintigraphy in granulomatous diseases

    Energy Technology Data Exchange (ETDEWEB)

    Vanhagen, P.M. (Dept. of Internal Medicine 3, Dijkzigt Univ. Hospital, Rotterdam (Netherlands) Dept. of Immunology, Dijkzigt Univ. Hospital, Rotterdam (Netherlands)); Krenning, E.P. (Dept. of Internal Medicine 3, Dijkzigt Univ. Hospital, Rotterdam (Netherlands) Dept. of Nuclear Medicine, Dijkzigt Univ. Hospital, Rotterdam (Netherlands)); Reubi, J.C. (Inst. of Pathology, Bern Univ. (Switzerland)); Kwekkeboom, D.J. (Dept. of Nuclear Medicine, Dijkzigt Univ. Hospital, Rotterdam (Netherlands)); Bakker, W.H. (Dept. of Nuclear Medicine, Dijkzigt Univ. Hospital, Rotterdam (Netherlands)); Mulder, A.H. (Dept. of Pathology, Dijkzigt Univ. Hospital, Rotterdam (Netherlands)); Laissue, I. (Inst. of Pathology, Bern Univ. (Switzerland)); Hoogstede, H.C. (Dept. of Chest Medicine, Dijkzigt Univ. Hospital, Rotterdam (Netherlands)); Lamberts, S.W.J. (Dept. of Internal Medicine 3, Dijkzigt Univ. Hospital, Rotterdam (Netherlands))

    1994-06-01

    In the present study 20 consecutive patients were investigated, 12 with sarcoidosis, one with both sarcoidosis and aspergillosis, four with tuberculosis and three with Wegener's granulomatosis. For in vivo SS-R imaging, total-body scintigraphy was performed 24 and 48 h after the administration of [sup 111]In-octreotide. Granuloma localizations could be visualized in all patients studied; additional sites were found in nine patients with sarcoidosis and in two patients with tuberculosis. In vitro autoradiography of fresh tissue biopsies, using the SS analogue [[sup 125]I-Tyr[sup 3

  17. JACoW Lightweight acquisition system for analogue signals

    CERN Document Server

    Bielawski, Bartosz

    2018-01-01

    In a complex machine such as a particle accelerator there are thousands of analogue signals that need monitoring and even more signals that could be used for debugging or as a tool for detecting symptoms of potentially avoidable problems. Usually it is not feasible to acquire and monitor all of these signals not only because of the cost but also because of cabling and space required. The Radio Frequency system in the Large Hadron Collider (LHC) is protected by multiple hardware interlocks that ensure safe operation of klystrons, superconducting cavities and all the other equipment. In parallel, a diagnostic system has been deployed to monitor the health of the klystrons. Due to the limited amount of space and the moderate number of signals to be monitored, a standard approach with a full VME or Compact PCI crate has not been selected. Instead, small embedded industrial computers with Universal Serial Bus (USB) oscilloscopes chosen for the specific application have been installed. This cost effective, rapidly ...

  18. Terrestrial carbon storage dynamics: Chasing a moving target

    Science.gov (United States)

    Luo, Y.; Shi, Z.; Jiang, L.; Xia, J.; Wang, Y.; Kc, M.; Liang, J.; Lu, X.; Niu, S.; Ahlström, A.; Hararuk, O.; Hastings, A.; Hoffman, F. M.; Medlyn, B. E.; Rasmussen, M.; Smith, M. J.; Todd-Brown, K. E.; Wang, Y.

    2015-12-01

    Terrestrial ecosystems have been estimated to absorb roughly 30% of anthropogenic CO2 emissions. Past studies have identified myriad drivers of terrestrial carbon storage changes, such as fire, climate change, and land use changes. Those drivers influence the carbon storage change via diverse mechanisms, which have not been unified into a general theory so as to identify what control the direction and rate of terrestrial carbon storage dynamics. Here we propose a theoretical framework to quantitatively determine the response of terrestrial carbon storage to different exogenous drivers. With a combination of conceptual reasoning, mathematical analysis, and numeric experiments, we demonstrated that the maximal capacity of an ecosystem to store carbon is time-dependent and equals carbon input (i.e., net primary production, NPP) multiplying by residence time. The capacity is a moving target toward which carbon storage approaches (i.e., the direction of carbon storage change) but usually does not attain. The difference between the capacity and the carbon storage at a given time t is the unrealized carbon storage potential. The rate of the storage change is proportional to the magnitude of the unrealized potential. We also demonstrated that a parameter space of NPP, residence time, and carbon storage potential can well characterize carbon storage dynamics quantified at six sites ranging from tropical forests to tundra and simulated by two versions (carbon-only and coupled carbon-nitrogen) of the Australian Community Atmosphere-Biosphere Land Ecosystem (CABLE) Model under three climate change scenarios (CO2 rising only, climate warming only, and RCP8.5). Overall this study reveals the unified mechanism unerlying terrestrial carbon storage dynamics to guide transient traceability analysis of global land models and synthesis of empirical studies.

  19. Terrestrial Zone Exoplanets and Life

    Science.gov (United States)

    Matthews, Brenda

    2018-01-01

    One of the most exciting results from ALMA has been the detection of significant substructure within protoplanetary disks that can be linked to planet formation processes. For the first time, we are able to observe the process of assembly of material into larger bodies within such disks. It is not possible, however, for ALMA to probe the growth of planets in protoplanetary disks at small radii, i.e., in the terrestrial zone, where we expect rocky terrestrial planets to form. In this regime, the optical depths prohibit observation at the high frequencies observed by ALMA. To probe the effects of planet building processes and detect telltale gaps and signatures of planetary mass bodies at such small separations from the parent star, we require a facility of superior resolution and sensitivity at lower frequencies. The ngVLA is just such a facility. We will present the fundamental science that will be enabled by the ngVLA in protoplanetary disk structure and the formation of planets. In addition, we will discuss the potential for an ngVLA facility to detect the molecules that are the building blocks of life, reaching limits well beyond those reachable with the current generation of telescopes, and also to determine whether such planets will be habitable based on studies of the impact of stars on their nearest planetary neighbours.

  20. Global Drainage Patterns to Modern Terrestrial Sedimentary Basins and its Influence on Large River Systems

    Science.gov (United States)

    Nyberg, B.; Helland-Hansen, W.

    2017-12-01

    Long-term preservation of alluvial sediments is dependent on the hydrological processes that deposit sediments solely within an area that has available accomodation space and net subsidence know as a sedimentary basin. An understanding of the river processes contributing to terrestrial sedimentary basins is essential to fundamentally constrain and quantify controls on the modern terrestrial sink. Furthermore, the terrestrial source to sink controls place constraints on the entire coastal, shelf and deep marine sediment routing systems. In addition, the geographical importance of modern terrestrial sedimentary basins for agriculture and human settlements has resulted in significant upstream anthropogenic catchment modification for irrigation and energy needs. Yet to our knowledge, a global catchment model depicting the drainage patterns to modern terrestrial sedimentary basins has previously not been established that may be used to address these challenging issues. Here we present a new database of 180,737 global catchments that show the surface drainage patterns to modern terrestrial sedimentary basins. This is achieved by using high resolution river networks derived from digital elevation models in relation to newly acquired maps on global modern sedimentary basins to identify terrestrial sinks. The results show that active tectonic regimes are typically characterized by larger terrestrial sedimentary basins, numerous smaller source catchments and a high source to sink relief ratio. To the contrary passive margins drain catchments to smaller terrestrial sedimentary basins, are composed of fewer source catchments that are relatively larger and a lower source to sink relief ratio. The different geomorphological characteristics of source catchments by tectonic setting influence the spatial and temporal patterns of fluvial architecture within sedimentary basins and the anthropogenic methods of exploiting those rivers. The new digital database resource is aimed to help

  1. Riparian vegetation in the alpine connectome: Terrestrial-aquatic and terrestrial-terrestrial interactions.

    Science.gov (United States)

    Zaharescu, Dragos G; Palanca-Soler, Antonio; Hooda, Peter S; Tanase, Catalin; Burghelea, Carmen I; Lester, Richard N

    2017-12-01

    Alpine regions are under increased attention worldwide for their critical role in early biogeochemical cycles, their high sensitivity to environmental change, and as repositories of natural resources of high quality. Their riparian ecosystems, at the interface between aquatic and terrestrial environments, play important geochemical functions in the watershed and are biodiversity hotspots, despite a harsh climate and topographic setting. With climate change rapidly affecting the alpine biome, we still lack a comprehensive understanding of the extent of interactions between riparian surface, lake and catchment environments. A total of 189 glacial - origin lakes were surveyed in the Central Pyrenees to test how key elements of the lake and terrestrial environments interact at different scales to shape riparian plant composition. Secondly, we evaluated how underlying ecotope features drive the formation of natural communities potentially sensitive to environmental change and assessed their habitat distribution. At the macroscale, vegetation composition responded to pan-climatic gradients altitude and latitude, which captured in a narrow geographic area the transition between large European climatic zones. Hydrodynamics was the main catchment-scale factor connecting riparian vegetation with major water fluxes, followed by topography and geomorphology. Lake sediment Mg and Pb, and water Mn and Fe contents reflected local influences from mafic bedrock and soil water saturation. Community analysis identified four keystone ecosystems: (i) damp ecotone, (ii) snow bed-silicate bedrock, (iii) wet heath, and (iv) calcareous substrate. These communities and their connections with ecotope elements could be at risk from a number of environmental change factors including warmer seasons, snow line and lowland species advancement, increased nutrient/metal input and water level fluctuations. The results imply important natural terrestrial-aquatic linkages in the riparian environment

  2. [Extrasolar terrestrial planets and possibility of extraterrestrial life].

    Science.gov (United States)

    Ida, Shigeru

    2003-12-01

    Recent development of research on extrasolar planets are reviewed. About 120 extrasolar Jupiter-mass planets have been discovered through the observation of Doppler shift in the light of their host stars that is caused by acceleration due to planet orbital motions. Although the extrasolar planets so far observed may be limited to gas giant planets and their orbits differ from those of giant planets in our Solar system (Jupiter and Saturn), the theoretically predicted probability of existence of extrasolar terrestrial planets that can have liquid water ocean on their surface is comparable to that of detectable gas giant planets. Based on the number of extrasolar gas giants detected so far, about 100 life-sustainable planets may exist within a range of 200 light years. Indirect observation of extrasolar terrestrial planets would be done with space telescopes within several years and direct one may be done within 20 years. The latter can detect biomarkers on these planets as well.

  3. A note on regular martingales in Riesz spaces | Korostenski ...

    African Journals Online (AJOL)

    ... setting of Riesz spaces. The aim of this note is to show that the space of such martingales is a Riesz space. We derive an analogue of a result of Troitsky's on regular norm bounded martingales in Banach lattices. Keywords: filtration; martingale; submartingale; Riesz space. Quaestiones Mathematicae 31(2008), 219–224 ...

  4. U.S. Nuclear Regulatory Commission natural analogue research program

    International Nuclear Information System (INIS)

    Kovach, L.A.; Ott, W.R.

    1995-01-01

    This article describes the natural analogue research program of the U.S. Nuclear Regulatory Commission (US NRC). It contains information on the regulatory context and organizational structure of the high-level radioactive waste research program plan. It also includes information on the conditions and processes constraining selection of natural analogues, describes initiatives of the US NRC, and describes the role of analogues in the licensing process

  5. AdS and dS black hole solutions in analogue gravity: The relativistic and nonrelativistic cases

    Science.gov (United States)

    Dey, Ramit; Liberati, Stefano; Turcati, Rodrigo

    2016-11-01

    We show that Schwarzschild black hole solutions in asymptotically anti-de Sitter (AdS) and de Sitter spaces may, up to a conformal factor, be reproduced in the framework of analogue gravity. The aforementioned derivation is performed using relativistic and nonrelativistic Bose-Einstein condensates. In addition, we demonstrate that the (2 +1 ) planar AdS black hole can be mapped into the nonrelativistic acoustic metric. Given that AdS black holes are extensively employed in the gauge/gravity duality, we then comment on the possibility of studying the AdS/CFT correspondence and gravity/fluid duality from an analogue gravity perspective.

  6. Ways to Optimize Analogue Switched Circuits

    Directory of Open Access Journals (Sweden)

    J. Hospodka

    2008-12-01

    Full Text Available This paper describes how analogue switched circuits (switched-capacitor and switched-current circuits can be optimized by means of a personal computer. The optimization of this kind of circuits is not so common and their analysis is more difficult in comparison with continuously working circuits. Firstly, the nonidealities occurring in these circuits whose effect on their characteristics should be optimized are discussed. Then a few ways to analyze analogue switched circuits are shown. From all optimization algorithms applicable for this kind of optimization, two ones that seem to be the most promising are proposed. The differential evolution (one of evolutionary algorithms combined with the simplex method was found to be most appropriate from these two ones. Two types of programs are required for the optimization of these circuits: a program for implementing calculations of the used optimization algorithm and a program for the analysis of the optimized circuit. Several suitable computer programs from both of the groups together with their proper settings according to authors’ experience are proposed. At the end of the paper, an example of a switched-current circuit optimization documenting the previous description is presented.

  7. Andrographolide and analogues in cancer prevention.

    Science.gov (United States)

    Mishra, Siddhartha Kumar; Tripathi, Swati; Shukla, Archana; Oh, Seung Hyun; Kim, Hwan Mook

    2015-01-01

    Andrographis paniculata is a medicinal plant traditionally used for treatment of cough and cold, fever, laryngitis, and several infectious diseases. Extracts of A. paniculata have shown versatile potency against various diseases including cancer. The active biomolecules of A. paniculata mainly are lactone and diterpene. Andrographolide and analogues have been widely used for prevention of different diseases. Andrographolides have shown potent antiinflammatory and anticancer activities. It showed potentials as chemopreventive agents by suppressing growth of cancer cells by inhibiting NF-kappaB, PI3K/AKT and other kinase pathways and by inducing apoptosis. Andrographolide induced both intrinsic and extrinsic apoptosis pathway in different cancer cells via expression of different anti-apoptotic protein like Bax, p53, and activated caspases. Andrographolide was successfully used as an antineoplastic drug in cancer chemotherapy. Andrographolide inhibited the growth of human breast, prostate, and hepatoma tumors. Andrographolide and analogues need to be subjected to further clinical and biomedical studies in cancer chemoprevention. Andrographolide could be potent anticancer agent when used in combination with other chemotherapeutic agents.

  8. Solar--terrestrial relations: stone age to space age

    International Nuclear Information System (INIS)

    Siscoe, G.L.

    1976-01-01

    A historical account of auroral displays recorded since the seventh century B.C. is given. The geological history of the earth's geomagnetic dipole and mechanisms of auroral production are discussed. Archeological implications of aurorae such as folk traditions of Eskimo cultures are mentioned. 34 references

  9. 3D Flash LIDAR Space Laser, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Advanced Scientific Concepts, Inc. (ASC) is a small business that has developed 3D Flash LIDAR systems for space and terrestrial applications. 3D Flash LIDAR is...

  10. Isotope powered Stirling generator for terrestrial applications

    International Nuclear Information System (INIS)

    Tingey, G.L.; Sorensen, G.C.; Ross, B.A.

    1995-01-01

    An electric power supply, small enough to be man-portable, is being developed for remote, terrestrial applications. This system is designed for an operating lifetime of five years without maintenance or refueling. A small Radioisotope Stirling Generator (RSG) has been developed. The energy source of the generator is a 60 watt plutonium-238 fuel clad used in the General Purpose Heat Sources (GPHS) developed for space applications. A free piston Stirling Engine drives a linear alternator to convert the heat to power. The system weighs about 7.5 kg and produces 11 watts AC power with a conversion efficiency of 18.5%. Two engine models have been designed, fabricated, and tested to date: (a) a developmental model instrumented to confirm and test parameters, and (b) an electrically heated model with an electrical heater equipped power input leads. Critical components have been tested for 10,000 to 20,000 hours. One complete generator has been operating for over 11,000 hours. Radioisotope heated prototypes are expected to be fabricated and tested in late 1995

  11. Isotope powered stirling generator for terrestrial applications

    International Nuclear Information System (INIS)

    Tingey, G.L.; Sorensen, G.C.; Ross, B.A.

    1995-01-01

    An electric power supply, small enough to be man-portable, is being developed for remote, terrestrial applications. This system is designed for an operating lifetime of five years without maintenance or refueling. A small Radioisotope Stirling Generator (RSG) has been developed. The energy source of the generator is a 60 watt plutonium-238 fuel clad used in the General Purpose Heat Sources (GPHS) developed for space applications. A free piston Stirling ENgine drives a linear alternator to convert the heat to power. The system weighs about 7.5 kg and produces 11 watts AC power with a conversion efficiency of 18.5%. Two engine models have been designed, fabricated, and tested to data: (a) a development model instrumented to confirm and test parameters, and (b) an electrically heated model with an electrical heater equipped power input leads. Critical components have been tested for 10,000 to 20,000 hours. One complete generator has been operating for over 11,000 hours. Radioisotope heated prototypes are expected to be fabricated and tested in late 1995. copyright 1995 American Institute of Physics

  12. Using Artificial Life to Assess the Typicality of Terrestrial Life: Implications for Human Mission Planetary Protection

    Science.gov (United States)

    Lupisella, Mark; Powers, Edward I. (Technical Monitor)

    2001-01-01

    The extent to which extraterrestrial life questions can be addressed, in the absence of an actual example, rests in some measure on the extent to which terrestrial life is representative of life in general since we will likely have to draw heavily, if not completely, from terrestrial life research. One example of a practical question involving extraterrestrial life that arises in preparing for a human mission to another planet such as Mars, is trying to assess and minimize the possible adverse effects of the presence of humans on possible indigenous extraterrestrial life-forms. This paper will present some key planetary protection challenges for a human Mars mission and then focus on one possible approach for assessing the extent to which terrestrial life is representative of biological phenomena in general, informing perhaps, the level of confidence we might have in applying terrestrial research - to extraterrestrial life issues. The approach involves appealing to the relatively new field of Artificial Life (A-Life) to: (1) use what might be the most basic minimal set of life-defining characteristics in (2) a large number of open-ended Artificial Life simulations to generate a "life possibility space" (3) the products of which can be examined for their plausibility within the context of relevant constraining knowledge, so that (4) the remaining possibility space can be examined for its variability relative to terrestrial life, where low variability might suggest that terrestrial life is representative of life in general, and high variability would indicate otherwise.

  13. Terrestrial atmosphere, water and astrobiology

    Directory of Open Access Journals (Sweden)

    Coradini M.

    2010-12-01

    Full Text Available Primitive life, defined as a chemical system capable to transfer its molecular information via self-replication and also capable to evolve, originated about 4 billion years ago from the processing of organic molecules by liquid water. Terrestrial atmosphere played a key role in the process by allowing the permanent presence of liquid water and by participating in the production of carbon-based molecules. Water molecules exhibit specific properties mainly due to a dense network of hydrogen bonds. The carbon-based molecules were either home made in the atmosphere and/or in submarine hydrothermal systems or delivered by meteorites and micrometeorites. The search for possible places beyond the earth where the trilogy atmosphere/water/life could exist is the main objective of astrobiology. Within the Solar System, exploration missions are dedicated to Mars, Europa, Titan and the icy bodies. The discovery of several hundreds of extrasolar planets opens the quest to the whole Milky Way.

  14. Traumatic insemination in terrestrial arthropods.

    Science.gov (United States)

    Tatarnic, Nikolai J; Cassis, Gerasimos; Siva-Jothy, Michael T

    2014-01-01

    Traumatic insemination is a bizarre form of mating practiced by some invertebrates in which males use hypodermic genitalia to penetrate their partner's body wall during copulation, frequently bypassing the female genital tract and ejaculating into their blood system. The requirements for traumatic insemination to evolve are stringent, yet surprisingly it has arisen multiple times within invertebrates. In terrestrial arthropods traumatic insemination is most prevalent in the true bug infraorder Cimicomorpha, where it has evolved independently at least three times. Traumatic insemination is thought to occur in the Strepsiptera and has recently been recorded in fruit fly and spider lineages. We review the putative selective pressures that may have led to the evolution of traumatic insemination across these lineages, as well as the pressures that continue to drive divergence in male and female reproductive morphology and behavior. Traumatic insemination mechanisms and attributes are compared across independent lineages.

  15. Radionuclide transfer in terrestrial animals

    International Nuclear Information System (INIS)

    DiGregorio, D.; Kitchings, T.; Van Voris, P.

    1978-01-01

    The analysis of dispersion of radionuclides in terrestrial food chains, generally, is a series of equations identifying the fractional input and outflow rates from trophic level to trophic level. Data that are prerequisite inputs for these food chain transport models include: (1) identification of specific transport pathway, (2) assimilation at each pathway link, and (3) the turnover rate or retention function by successive receptor species in the appropriate food chain. In this report, assimilation coefficients, biological half-lives, and excretion rates for a wide variety of vertebrate and invertebrate species and radionuclides have been compiled from an extensive search of the available literature. Using the information accumulated from the literature, correlations of nuclide metabolism and body weight are also discussed. (author)

  16. Terrestrial pathways of radionuclide particulates

    International Nuclear Information System (INIS)

    Boone, F.W.; Ng, Y.C.

    1981-01-01

    Formulations are developed for computing potential human intake of 13 radionuclides via the terrestrial food chains. The formulations are an extension of the NRC methodology. Specific regional crop and livestock transfer and fractional distribution data from the southern part of the U.S.A. are provided and used in the computation of comparative values with those computed by means of USNRC Regulatory Guide 1.109 formulations. In the development of the model, emphasis was also placed on identifying the various time-delay compartments of the food chains and accounting for all of the activity initially deposited. For all radionuclides considered, except 137 Cs, the new formulations predict lower potential intakes from the total of all food chains combined than do the comparable Regulatory Guide formulations by as much as a factor of 40. For 137 Cs the new formulations predict 10% higher potential intakes. (author)

  17. Phytopharmacological overview of Tribulus terrestris

    Science.gov (United States)

    Chhatre, Saurabh; Nesari, Tanuja; Somani, Gauresh; Kanchan, Divya; Sathaye, Sadhana

    2014-01-01

    Tribulus terrestris (family Zygophyllaceae), commonly known as Gokshur or Gokharu or puncture vine, has been used for a long time in both the Indian and Chinese systems of medicine for treatment of various kinds of diseases. Its various parts contain a variety of chemical constituents which are medicinally important, such as flavonoids, flavonol glycosides, steroidal saponins, and alkaloids. It has diuretic, aphrodisiac, antiurolithic, immunomodulatory, antidiabetic, absorption enhancing, hypolipidemic, cardiotonic, central nervous system, hepatoprotective, anti-inflammatory, analgesic, antispasmodic, anticancer, antibacterial, anthelmintic, larvicidal, and anticariogenic activities. For the last few decades or so, extensive research work has been done to prove its biological activities and the pharmacology of its extracts. The aim of this review is to create a database for further investigations of the discovered phytochemical and pharmacological properties of this plant to promote research. This will help in confirmation of its traditional use along with its value-added utility, eventually leading to higher revenues from the plant. PMID:24600195

  18. Variational calculus on Banach spaces

    International Nuclear Information System (INIS)

    Uglanov, A V

    2000-01-01

    The problem of variational calculus is considered in a (variable) subdomain of a Banach space. Analogues of the basic principles of the finite-dimensional theory are derived: the main formula for variations of a functional, necessary conditions of an extremum, Noether's theorem. All the results obtained are dimension-invariant and become the classical ones in the finite-dimensional setting. The main tool of the analysis is the theory of surface integration in Banach spaces

  19. A Spherical Aerial Terrestrial Robot

    Science.gov (United States)

    Dudley, Christopher J.

    This thesis focuses on the design of a novel, ultra-lightweight spherical aerial terrestrial robot (ATR). The ATR has the ability to fly through the air or roll on the ground, for applications that include search and rescue, mapping, surveillance, environmental sensing, and entertainment. The design centers around a micro-quadcopter encased in a lightweight spherical exoskeleton that can rotate about the quadcopter. The spherical exoskeleton offers agile ground locomotion while maintaining characteristics of a basic aerial robot in flying mode. A model of the system dynamics for both modes of locomotion is presented and utilized in simulations to generate potential trajectories for aerial and terrestrial locomotion. Details of the quadcopter and exoskeleton design and fabrication are discussed, including the robot's turning characteristic over ground and the spring-steel exoskeleton with carbon fiber axle. The capabilities of the ATR are experimentally tested and are in good agreement with model-simulated performance. An energy analysis is presented to validate the overall efficiency of the robot in both modes of locomotion. Experimentally-supported estimates show that the ATR can roll along the ground for over 12 minutes and cover the distance of 1.7 km, or it can fly for 4.82 minutes and travel 469 m, on a single 350 mAh battery. Compared to a traditional flying-only robot, the ATR traveling over the same distance in rolling mode is 2.63-times more efficient, and in flying mode the system is only 39 percent less efficient. Experimental results also demonstrate the ATR's transition from rolling to flying mode.

  20. Identifying climate analogues for precipitation extremes for Denmark based on RCM simulations from the ENSEMBLES database

    DEFF Research Database (Denmark)

    Arnbjerg-Nielsen, Karsten; Funder, S. G.; Madsen, H.

    2015-01-01

    change over time. The study focuses on assessing climate analogues for Denmark based on current climate data set (E-OBS) observations as well as the ENSEMBLES database of future climates with the aim of projecting future precipitation extremes. The local present precipitation extremes are assessed......Climate analogues, also denoted Space-For-Time, may be used to identify regions where the present climatic conditions resemble conditions of a past or future state of another location or region based on robust climate variable statistics in combination with projections of how these statistics...... by means of intensity-duration-frequency curves for urban drainage design for the relevant locations being France, the Netherlands, Belgium, Germany, the United Kingdom, and Denmark. Based on this approach projected increases of extreme precipitation by 2100 of 9 and 21% are expected for 2 and 10 year...

  1. The cosmic gorilla effect or the problem of undetected non terrestrial intelligent signals

    Science.gov (United States)

    G. De la Torre, Gabriel; Garcia, Manuel A.

    2018-05-01

    This article points to a long lasting problem in space research and cosmology, the problem of undetected signs of non terrestrial life and civilizations. We intentionally avoid the term extraterrestrial as we consider other possibilities that may arise but not fall strictly within the extraterrestrial scope. We discuss the role of new physics including dark matter and string theory in the search for life and other non terrestrial intelligence. A new classification for non terrestrial civilizations with three types and five dimensions is also provided. We also explain how our own neurophysiology, psychology and consciousness can play a major role in this search of non terrestrial civilizations task and how they have been neglected up to this date. To test this, 137 adults were evaluated using the cognitive reflection test, an attention/awareness questionnaire and a visuospatial searching task with aerial view images to determine the presence of inattentional blindness.

  2. Hepatoprotective and Antioxidant Activities of Tribulus Terrestris

    NARCIS (Netherlands)

    Harraz, Fathalla M; Ghazy, Nabila M; Hammoda, Hala M; Nafeaa, Abeer A.; Abdallah, Ingy I.

    2015-01-01

    Tribulus terrestris L. has been used in folk medicine throughout history. The present study examined the acute toxicity of the total ethanolic extract of T. Terrestris followed by investigation of the hepatoprotective activity of the total ethanolic extract and different fractions of the aerial

  3. A terrestrial Eocene stack: tying terrestrial lake ecology to marine carbon cycling through the Early Eocene Climatic Optimum

    Science.gov (United States)

    Grogan, D. S.; Whiteside, J. H.; Musher, D.; Rosengard, S. Z.; Vankeuren, M. A.; Pancost, R. D.

    2010-12-01

    The lacustrine Green River Formation is known to span ≥15 million years through the early-middle Eocene, and recent work on radioisotopic dating has provided a framework on which to build ties to the orbitally-tuned marine Eocene record. Here we present a spliced stack of Fischer assay data from drilled cores of the Green River Formation that span both an East-West and a North-South transect of the Uinta Basin of Utah. Detailed work on two cores demonstrate that Fischer assay measurements covary with total organic carbon and bulk carbon isotopes, allowing us to use Fisher assay results as a representative carbon cycling proxy throughout the stack. We provide an age model for this core record by combining radioisotopic dates of tuff layers with frequency analysis of Fischer assay measurements. Identification of orbital frequencies tied directly to magnetochrons through radioisotopic dates allows for a direct comparison of the terrestrial to the marine Eocene record. Our analysis indicates that the marker beds used to correlate the stack cores represent periods of enhanced lake productivity and extreme carbon burial; however, unlike the hyperthermal events that are clearly marked in the marine Eocene record, the hydrocarbon-rich "Mahogany Bed" period of burial does not correspond to a clear carbon isotope excursion. This suggests that the terrestrial realm may have experienced extreme ecological responses to relatively small perturbations in the carbon cycle during the Early Eocene Climatic Optimum. To investigate the ecological responses to carbon cycle perturbations through the hydrocarbon rich beds, we analyzed a suite of microbial biomarkers, finding evidence for cyanobacteria, dinoflagellates, and potentially green sulfur bacteria. These taxa indicate fluctuating oxic/anoxic conditions in the lake during abrupt intervals of carbon burial, suggesting a lake biogeochemical regime with no modern analogues.

  4. The circumpolar biodiversity monitoring program - Terrestrial plan

    DEFF Research Database (Denmark)

    Christensen, Tom; Payne, J.; Doyle, M.

    The Circumpolar Biodiversity Monitoring Program, CBMP, Terrestrial Plan, www.caff.is/terrestrial, is a framework to focus and coordinate monitoring of terrestrial biodiversity across the Arctic. The goal of the plan is to improve the collective ability of Arctic traditional knowledge (TK) holders......, northern communities, and scientists to detect, understand and report on long-term change in Arctic terrestrial ecosystems and biodiversity. This presentation will outline the key management questions the plan aims to address and the proposed nested, multi-scaled approach linking targeted, research based...... monitoring with survey-based monitoring and remotely sensed data. The CBMP Terrestrial Plan intends to build upon and expand existing monitoring networks, engaging participants across a range of capacity and interests. The presentation will summarize the recommended focal soil ecosystem components...

  5. The Crisis of Public Local Digital Terrestrial Television in Spain: The case of Catalonia

    Directory of Open Access Journals (Sweden)

    Federica Alborch-Gil, M.A.

    2011-01-01

    Full Text Available The article describes and analyses the state of public local digital terrestrial television (L-DTT in Catalonia just after the analogue switch-off in April 2010. The results show that only 12 of the 37 anticipated public television channels were broadcasting, and only five more were expected to do so in the medium term. These data indicate that public local television was experiencing a crisis in the context of the digital switchover process: while some digital programmes were finding it hard to get off the ground due to severe limitations, other historical analogue stations were disappearing.The article is grounded on qualitative research based on in-depth interviews with representatives of the 37 aforementioned channels. The objectives of the paper are: to describe the L-DTT model and its roll-out status in Catalonia as at May 2010; to provide interpretative elements to explain the crisis identified; and to provide insights for the formulation of hypotheses about the state of the sector in the rest of Spain. The results suggest that the problems of public L-DTT stem from the digital roll-out policies of the Government of Spain and the Government of Catalonia, neither of which – especially the first – seems to have taken into account the pre-existing analogue reality. In this respect, the Catalan case offers signs and evidence that can be extrapolated to the situation in Spain as a whole.

  6. Jupiter analogues and planets of active stars

    Directory of Open Access Journals (Sweden)

    Henning T.

    2013-04-01

    Full Text Available Combined results are now available from a 15 year long search for Jupiter analogues around solar-type stars using the ESO CAT + CES, ESO 3.6 m + CES, and ESO 3.6 m + HARPS instruments. They comprise planet (co-discoveries (ι Hor and HR 506 and confirmations (three planets in HR 3259 as well as non-confirmations of planets (HR 4523 and ɛ Eri announced elsewhere. A long-term trend in ɛ Ind found by our survey is probably attributable to a Jovian planet with a period >30 yr, but we cannot fully exclude stellar activity effects as the cause. A 3.8 year periodic variation in HR 8323 can be attributed to stellar activity.

  7. The gravitational analogue of the Witten effect

    International Nuclear Information System (INIS)

    Foda, O.

    1984-06-01

    In the presence of massive fermions, and assuming a non-vanishing theta-parameter as the only source of CP-violation, the Witten effect [a shift in the electric charge of a magnetic monopole due to CP-non-conservation] is shown to follow from an anomalous chiral commutator. Next, given the gravitational contribution to the chiral anomaly, the corresponding anomalous commutator for Dirac fermion currents in a gravitational background is derived. From that, we infer the equivalence of a theta R-tilde R term in the Lagrangian to a shift in the mass parameter of the NUT metric, in proportion to theta. This is interpreted as the gravitational analogue of the Witten effect. Its relevance to certain Kaluza-Klein monopoles is briefly discussed. (author)

  8. Gravitational analogue of the Witten effect

    Energy Technology Data Exchange (ETDEWEB)

    Foda, O. (International Centre for Theoretical Physics, Trieste (Italy))

    1985-07-22

    In the presence of massive fermions, and assuming a non-vanishing theta-parameter as the only source of CP violation, the Witten effect (a shift in the electric charge of a magnetic monopole due to CP non-conservation) is shown to follow from an anomalous chiral commutator. Next, given the gravitational contribution to the chiral anomaly, the corresponding anomalous commutator for Dirac fermion currents in a gravitational background is derived. From that, we infer the equivalence of a thetaR tildeR term in the lagrangian to a shift in the mass parameter of the NUT metric, in proportion to theta. This is interpreted as the gravitational analogue of the Witten effect. Its relevance to certain Kaluza-Klein monopoles is briefly discussed.

  9. The gravitational analogue of the Witten effect

    International Nuclear Information System (INIS)

    Foda, O.

    1985-01-01

    In the presence of massive fermions, and assuming a non-vanishing theta-parameter as the only source of CP violation, the Witten effect (a shift in the electric charge of a magnetic monopole due to CP non-conservation) is shown to follow from an anomalous chiral commutator. Next, given the gravitational contribution to the chiral anomaly, the corresponding anomalous commutator for Dirac fermion currents in a gravitational background is derived. From that, we infer the equivalence of a thetaR tildeR term in the lagrangian to a shift in the mass parameter of the NUT metric, in proportion to theta. This is interpreted as the gravitational analogue of the Witten effect. Its relevance to certain Kaluza-Klein monopoles is briefly discussed. (orig.)

  10. Reflective analogue optical link operating issues

    CERN Document Server

    Batten, Jeremy

    1996-01-01

    The proposed readout of analogue data from CMS tracker will use an optical fibre link. The choice of transmitter/receiver technology, however, has been the subject of intense research and development by the RD23 collaboration. One solution uses passive devices, multi-quantum well modulators, at the detector front end, and continuous wave driving lasers at the readout back end. This system has been tested at Imperial College. We report on the following: problems of noise associated with multimoded behaviour of a degraded laser; measurements of laser wavelength dependence on both drive current and temperature; and modulator reflectance dependence on laser wavelength. We extrapolate the findings to system issues, highlighting the degree of temperature control required of the driving laser.

  11. The glaciogenic reservoir analogue studies project (GRASP)

    DEFF Research Database (Denmark)

    Moscariello, A.; Moreau, Julien; Vegt, P. van der

    increasing the risk associated with developing effectively these reservoirs. Therefore a analogue-based predictive stratigraphical and sedimentological model can help to steer drilling strategy and reduce uncertainties and associated risks. For this purpose the GRASP joint industry programme was established......Tunnel galleys are common features in Palaeozoic glacigenic succession in North Afrcica and Middle East and they are amongst the most challenging target for hydrocarbon exploration and developing drilling in these regions. Similarly, these buried valleys form important groundwater reservoirs...... in Quaternary glaciated areas and their nature and sediment composition is critical to drive a sustainable production strategy and assess their vulnerability. Seismic resolution however, often limits the understanding of channel valleys morphology, 3D geometry and internal reservoir distribution, thus...

  12. Synthesis of an Orthogonal Topological Analogue of Helicene

    DEFF Research Database (Denmark)

    Wixe, Torbjörn; Wallentin, Carl‐Johan; Johnson, Magnus T.

    2013-01-01

    The synthesis of an orthogonal topological pentamer analogue of helicene is presented. This analogue forms a tubular structure with its aromatic systems directed parallel to the axis of propagation, which creates a cavity with the potential to function as a host molecule. The synthetic strategy...

  13. Caged ceramide 1-phosphate analogues: synthesis and properties.

    Science.gov (United States)

    Lankalapalli, Ravi S; Ouro, Alberto; Arana, Lide; Gómez-Muñoz, Antonio; Bittman, Robert

    2009-11-20

    Sphingolipid phosphate analogues bearing 7-(diethylamino)coumarin (DECM) and 4-bromo-5-hydroxy-2-nitrobenzhydryl (BHNB) groups in a photolabile ester bond were synthesized. The ability of the "caged" ceramide 1-phosphate analogues to release the bioactive parent molecule upon irradiation at 400-500 nm was demonstrated by stimulation of macrophage cell proliferation.

  14. Automated Layout Generation of Analogue and Mixed-Signal ASIC's

    DEFF Research Database (Denmark)

    Bloch, Rene

    The research and development carried out in this Ph.D. study focusses on two key areas of the design flow for analogue and mixed-signal integrated circuit design, the mixed-signal floorplanning and the analogue layout generation.A novel approach to floorplanning is presented which provides true i...

  15. Uncertainties and credibility building of safety analyses. Natural analogues

    International Nuclear Information System (INIS)

    Laciok, A.

    2001-07-01

    The substance of natural analogues and their studies is defined as a complementary method to laboratory and in-situ experiments and modelling. The role of natural analogues in the processes of development of repositories is defined, mainly in performance assessment of repository system and communication with public. The criteria for identification of natural analogues which should be evaluated in the phase of initiation of new studies are specified. Review part of this report is divided to study of natural analogues and study of anthropogenic and industrial analogues. The main natural analogue studies performed in various countries, in different geological setting, with various aims are characterized. New results acquired in recently finished studies are included: Palmottu (2nd phase of project financed by European Commission), Oklo (results of research financed also by European Commission), Maqarin (3rd phase) and other information obtained from last meetings and workshops of NAWG. In view of the fact that programmes of development of deep repositories in Czech and Slovak Republics are interconnected, the natural analogues studies carried out in the Czech republic are incorporated in separate chapter - study of uranium accumulation in Tertiary clays at Ruprechtov site and study of degradation of natural glasses. In final part the areas of natural analogue studies as an integral part of development of deep geological repository are proposed along with characterization of broader context and aspects of realization of these studies (international cooperation, preparation and evaluation of procedures, communication with public). (author)

  16. Insulin analogues and severe hypoglycaemia in type 1 diabetes

    DEFF Research Database (Denmark)

    Kristensen, P L; Hansen, L S; Jespersen, M J

    2012-01-01

    The effect of insulin analogues on glycaemic control is well-documented, whereas the effect on avoidance of severe hypoglycaemia remains tentative. We studied the frequency of severe hypoglycaemia in unselected patients with type 1 diabetes treated with insulin analogues, human insulin, or mixed...

  17. MAQARIN natural analogue study: phase III

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, W.R.; Mazurek, M.; Waber, H.N. [Univ. of Berne (Switzerland). Institutes of Geology, Mineralogy and Petrology, Rock-Water Interaction Group (GGWW); Arlinger, J.; Erlandson, A.C.; Hallbeck, L.; Pedersen, K. [Goeteborg University (Sweden). Dept. of General and Marine Microbiology; Boehlmann, W.; Fritz, P.; Geyer, S.; Geyer, W.; Hanschman, G.; Kopinke, F.D.; Poerschmann, J. [Umweltforschungszentrum Leipzig-Halle (Germany); Chambers, A.V.; Haworth, A.; Ilett, D.; Linklater, C.M.; Tweed, C.J. [AEA Technology plc, Harwell (United Kingdom); Chenery, S.R.N.; Kemp, S.J.; Milodowski, A.E.; Pearce, J.M.; Reeder, S.; Rochelle, C.A.; Smith, B.; Wetton, P.D.; Wragg, J. [British Geological Survey, Keyworth (United Kingdom); Clark, I.D. [Univ. of Ottawa (Canada). Dept. of Geology; Hodginson, E.; Hughes, C.R. [Univ. of Manchester (United Kingdom). Dept. of Earth Sciences; Hyslop, E.K. [British Geological Survey, Edinburgh (United Kingdom); Karlsson, F. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Khoury, H.N.; Salameh, E. [Univ. of Jordan, Amman (Jordan); Lagerblad, B. [Cement Institute, Stockholm (Sweden); Longworth, G. [Univ. of Manchester (United Kingdom). Dept. of Geology; Pitty, A.F. [Private consultant, Norwich (United Kingdom); Savage, D. [QuantiSci Ltd, Melton Mowbray (United Kingdom); Smellie, J.A.T. [ed.] [Conterra AB, Uppsala (Sweden)

    1998-12-01

    This report represents the conclusion to Phase III of the Maqarin Natural Analogue Study. The main thrust was to establish the origin and chemistry of the Western Springs hyper alkaline groundwaters (Na/K enriched Ca(OH){sub 2} type) and to study their interaction with rocks of different compositions, as natural analogues to key processes that might occur at an early stage within the `alkali disturbed zone` of cementitious repositories in different host rocks. Whilst earlier studies at Maqarin were very much site-specific and process-oriented, Phase III provided a regional perspective to the geological evolution of the Maqarin region. This was made possible by greater field access which allowed a more systematic structural and geomorphological study of the area. This has resulted in a greater understanding of the age and spatial relationships concerning formation of the cement zones through spontaneous combustion of the Bituminous Marls, and the subsequent formation of high pH groundwaters at the Eastern and Western Springs locations. At the Western Springs locality, hydrochemical and hydrogeological evaluation of new and published data (plus access to unpublished data), together with detailed mineralogical and geochemical studies, helped to clarify the very earliest stage of cement leachate/host rock interaction. The data were used also to test coupled flow/transport codes developed to assess the long-term evolution of a cementitious repository. Additional objectives addressed include: a) rock matrix diffusion, b) the occurrence and chemical controls on zeolite composition, e) the occurrence and chemical controls on clay stability, and d) the role of microbes, organics and colloids in trace element transport. The Maqarin site now provides a consistent picture explaining the origin of the hyperalkaline groundwaters, and is therefore a unique location for the examination of the mechanisms and processes associated with cementitious repositories. Application of these

  18. Natural analogues of nuclear waste glass corrosion

    International Nuclear Information System (INIS)

    Abrajano, T.A. Jr.; Ebert, W.L.; Luo, J.S.

    1999-01-01

    This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information available on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses

  19. Natural analogues of nuclear waste glass corrosion.

    Energy Technology Data Exchange (ETDEWEB)

    Abrajano, T.A. Jr.; Ebert, W.L.; Luo, J.S.

    1999-01-06

    This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information available on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses.

  20. MAQARIN natural analogue study: phase III

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, W.R.; Mazurek, M.; Waber, H.N. [Univ. of Berne (Switzerland). Institutes of Geology, Mineralogy and Petrology, Rock-Water Interaction Group (GGWW); Arlinger, J.; Erlandson, A.C.; Hallbeck, L.; Pedersen, K. [Goeteborg Univ. (Sweden). Dept. of General and Marine Microbiology; Boehlmann, W.; Fritz, P.; Geyer, S.; Geyer, W.; Hanschman, G.; Kopinke, F.D.; Poerschmann, J. [Umweltforschungszentrum Leipzig-Halle (Germany); Chambers, A.V.; Haworth, A.; Ilett, D.; Linklater, C.M.; Tweed, C.J. [AEA Technology plc, Harwell (United Kingdom); Chenery, S.R.N.; Kemp, S.J.; Milodowski, A.E.; Pearce, J.M.; Reeder, S.; Rochelle, C.A.; Smith, B.; Wetton, P.D.; Wragg, J. [British Geological Survey, Keyworth (United Kingdom); Clark, I.D. [Univ. of Ottawa (Canada). Dept. of Geology; Hodginson, E.; Hughes, C.R. [Univ. of Manchester (United Kingdom). Dept. of Earth Sciences; Hyslop, E.K. [British Geological Survey, Edinburgh (United Kingdom); Karlsson, F. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Khoury, H.N.; Salameh, E. [Univ. of Jordan, Amman (Jordan); Lagerblad, B. [Cement Inst., Stockholm (Sweden); Longworth, G. [Univ. of Manchester (United Kingdom). Dept. of Geology; Pitty, A.F. [Private consultant, Norwich (United Kingdom); Savage, D. [QuantiSci Ltd, Melton Mowbray (United Kingdom); Smellie, J.A.T. [ed.] [Conterra AB, Uppsala (Sweden)

    1998-12-01

    This report represents the conclusion to Phase III of the Maqarin Natural Analogue Study. The main thrust was to establish the origin and chemistry of the Western Springs hyper alkaline groundwaters (Na/K enriched Ca(OH){sub 2} type) and to study their interaction with rocks of different compositions, as natural analogues to key processes that might occur at an early stage within the `alkali disturbed zone` of cementitious repositories in different host rocks. Whilst earlier studies at Maqarin were very much site-specific and process-oriented, Phase III provided a regional perspective to the geological evolution of the Maqarin region. This was made possible by greater field access which allowed a more systematic structural and geomorphological study of the area. This has resulted in a greater understanding of the age and spatial relationships concerning formation of the cement zones through spontaneous combustion of the Bituminous Marls, and the subsequent formation of high pH groundwaters at the Eastern and Western Springs locations. At the Western Springs locality, hydrochemical and hydrogeological evaluation of new and published data (plus access to unpublished data), together with detailed mineralogical and geochemical studies, helped to clarify the very earliest stage of cement leachate/host rock interaction. The data were used also to test coupled flow/transport codes developed to assess the long-term evolution of a cementitious repository. Additional objectives addressed include: a) rock matrix diffusion, b) the occurrence and chemical controls on zeolite composition, e) the occurrence and chemical controls on clay stability, and d) the role of microbes, organics and colloids in trace element transport. The Maqarin site now provides a consistent picture explaining the origin of the hyperalkaline groundwaters, and is therefore a unique location for the examination of the mechanisms and processes associated with cementitious repositories. Application of these

  1. Magnetic properties of Proxima Centauri b analogues

    Science.gov (United States)

    Zuluaga, Jorge I.; Bustamante, Sebastian

    2018-03-01

    The discovery of a planet around the closest star to our Sun, Proxima Centauri, represents a quantum leap in the testability of exoplanetary models. Unlike any other discovered exoplanet, models of Proxima b could be contrasted against near future telescopic observations and far future in-situ measurements. In this paper we aim at predicting the planetary radius and the magnetic properties (dynamo lifetime and magnetic dipole moment) of Proxima b analogues (solid planets with masses of ∼ 1 - 3M⊕ , rotation periods of several days and habitable conditions). For this purpose we build a grid of planetary models with a wide range of compositions and masses. For each point in the grid we run the planetary evolution model developed in Zuluaga et al. (2013). Our model assumes small orbital eccentricity, negligible tidal heating and earth-like radiogenic mantle elements abundances. We devise a statistical methodology to estimate the posterior distribution of the desired planetary properties assuming simple lprior distributions for the orbital inclination and bulk composition. Our model predicts that Proxima b would have a mass 1.3 ≤Mp ≤ 2.3M⊕ and a radius Rp =1.4-0.2+0.3R⊕ . In our simulations, most Proxima b analogues develop intrinsic dynamos that last for ≥4 Gyr (the estimated age of the host star). If alive, the dynamo of Proxima b have a dipole moment ℳdip >0.32÷2.9×2.3ℳdip , ⊕ . These results are not restricted to Proxima b but they also apply to earth-like planets having similar observed properties.

  2. MAQARIN natural analogue study: phase III

    International Nuclear Information System (INIS)

    Alexander, W.R.; Mazurek, M.; Waber, H.N.; Arlinger, J.; Erlandson, A.C.; Hallbeck, L.; Pedersen, K.; Chambers, A.V.; Haworth, A.; Ilett, D.; Linklater, C.M.; Tweed, C.J.; Chenery, S.R.N.; Kemp, S.J.; Milodowski, A.E.; Pearce, J.M.; Reeder, S.; Rochelle, C.A.; Smith, B.; Wetton, P.D.; Wragg, J.; Clark, I.D.; Karlsson, F.; Khoury, H.N.; Salameh, E.; Lagerblad, B.; Longworth, G.; Savage, D.; Smellie, J.A.T.

    1998-12-01

    This report represents the conclusion to Phase III of the Maqarin Natural Analogue Study. The main thrust was to establish the origin and chemistry of the Western Springs hyper alkaline groundwaters (Na/K enriched Ca(OH) 2 type) and to study their interaction with rocks of different compositions, as natural analogues to key processes that might occur at an early stage within the 'alkali disturbed zone' of cementitious repositories in different host rocks. Whilst earlier studies at Maqarin were very much site-specific and process-oriented, Phase III provided a regional perspective to the geological evolution of the Maqarin region. This was made possible by greater field access which allowed a more systematic structural and geomorphological study of the area. This has resulted in a greater understanding of the age and spatial relationships concerning formation of the cement zones through spontaneous combustion of the Bituminous Marls, and the subsequent formation of high pH groundwaters at the Eastern and Western Springs locations. At the Western Springs locality, hydrochemical and hydrogeological evaluation of new and published data (plus access to unpublished data), together with detailed mineralogical and geochemical studies, helped to clarify the very earliest stage of cement leachate/host rock interaction. The data were used also to test coupled flow/transport codes developed to assess the long-term evolution of a cementitious repository. Additional objectives addressed include: a) rock matrix diffusion, b) the occurrence and chemical controls on zeolite composition, e) the occurrence and chemical controls on clay stability, and d) the role of microbes, organics and colloids in trace element transport. The Maqarin site now provides a consistent picture explaining the origin of the hyperalkaline groundwaters, and is therefore a unique location for the examination of the mechanisms and processes associated with cementitious repositories. Application of these

  3. Di-uniform texture spaces

    Directory of Open Access Journals (Sweden)

    Selma Ozcag

    2003-04-01

    Full Text Available Textures were introduced by the second author as a point-based setting for the study of fuzzy sets, and have since proved to be an appropriate framework for the development of complement-free mathematical concepts. In this paper the authors lay the foundation for a theory of uniformities in a textural context. Analogues are given for both the diagonal and covering approaches to the classical theory of uniform structures, the notion of uniform topology is generalized and an analogue given for the well known result that a topological space is uniformizable if and only if it is completely regular. Finally a textural analogue of the classical interplay between uniformities and families of pseudo-metrics is presented.

  4. Analogue Hawking radiation from astrophysical black-hole accretion

    International Nuclear Information System (INIS)

    Das, Tapas K

    2004-01-01

    We show that spherical accretion onto astrophysical black holes can be considered as a natural example of an analogue system. We provide, for the first time, an exact analytical scheme for calculating the analogue Hawking temperature and surface gravity for general relativistic accretion onto astrophysical black holes. Our calculation may bridge the gap between the theory of transonic astrophysical accretion and the theory of analogue Hawking radiation. We show that the domination of the analogue Hawking temperature over the actual Hawking temperature may be a real astrophysical phenomenon, though observational tests of this fact will at best be difficult and at worst might prove to be impossible. We also discuss the possibilities of the emergence of analogue white holes around astrophysical black holes. Our calculation is general enough to accommodate accreting black holes with any mass

  5. Estimating Exposure of Terrestrial Wildlife to Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Sample, B.E.

    1994-01-01

    This report presents a general model for exposure of terrestrial wildlife to contaminants (Sect. 2), methods for estimating parameters of the model (Sect. 3), species specific parameters for endpoint species on the Oak Ridge Reservation (ORR) (Sect. 4), and a sample application (Sect. 5). Exposure can be defined as the coincidence in both space and time of a receptor and a stressor, such that the receptor and stressor come into contact and interact (Risk Assessment Forum 1992). In the context of ecological risk assessment, receptors include all endpoint species or communities identified for a site [see Suter (1989) and Suter et al. (1994) for discussions of ecological endpoints for waste sites]. In the context of waste site assessments, stressors are chemical contaminations, and the contact and interaction are uptake of the contaminant by the receptor. Without sufficient exposure of the receptor to the contaminants, there is no ecological risk. Unlike some other endpoint assemblages, terrestrial wildlife are significantly exposed to contaminants in multiple media. They may drink or swim in contaminated water, ingest contaminated food and soil, and breath contaminated air. In addition, because most wildlife are mobile, moving among and within habitats, exposure is not restricted to a single location. They may integrate contamination from several spatially discrete sources. Therefore, exposure models for terrestrial wildlife must include multiple media. This document provides models and parameters for estimating exposure of birds and mammals. Reptiles and amphibians are not considered because few data exist with which to assess exposure to these organisms. In addition, because toxicological data are scarce for both classes, evaluation of the significance of exposure estimates is problematic. However, the general exposure estimation procedure developed herein for birds and mammals is applicable to reptiles and amphibians. Exposure models must be appropriate to the

  6. Space Weather Forecasting at IZMIRAN

    Science.gov (United States)

    Gaidash, S. P.; Belov, A. V.; Abunina, M. A.; Abunin, A. A.

    2017-12-01

    Since 1998, the Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation (IZMIRAN) has had an operating heliogeophysical service—the Center for Space Weather Forecasts. This center transfers the results of basic research in solar-terrestrial physics into daily forecasting of various space weather parameters for various lead times. The forecasts are promptly available to interested consumers. This article describes the center and the main types of forecasts it provides: solar and geomagnetic activity, magnetospheric electron fluxes, and probabilities of proton increases. The challenges associated with the forecasting of effects of coronal mass ejections and coronal holes are discussed. Verification data are provided for the center's forecasts.

  7. Application of Autonomous Spacecraft Power Control Technology to Terrestrial Microgrids

    Science.gov (United States)

    Dever, Timothy P.; Trase, Larry M.; Soeder, James F.

    2014-01-01

    This paper describes the potential of the power campus located at the NASA Glenn Research Center (GRC) in Cleveland, Ohio for microgrid development. First, the benefits provided by microgrids to the terrestrial power grid are described, and an overview of Technology Needs for microgrid development is presented. Next, GRC's work on development of autonomous control for manned deep space vehicles, which are essentially islanded microgrids, is covered, and contribution of each of these developments to the microgrid Technology Needs is detailed. Finally, a description is provided of GRC's existing physical assets which can be applied to microgrid technology development, and a phased plan for development of a microgrid test facility is presented.

  8. The rarity of terrestrial gamma-ray flashes

    OpenAIRE

    Smith, D. M.; Dwyer, J. R.; Hazelton, B. J.; Grefenstette, B. W.; Martinez-McKinney, G. F. M.; Zhang, Z. Y.; Lowell, A. W.; Kelley, N. A.; Splitt, M. E.; Lazarus, S. M.; Ulrich, W.; Schaal, M.; Saleh, Z. H.; Cramer, E.; Rassoul, H. K.

    2011-01-01

    We report on the first search for Terrestrial Gamma-ray Flashes (TGFs) from altitudes where they are thought to be produced. The Airborne Detector for Energetic Lightning Emissions (ADELE), an array of gamma-ray detectors, was flown near the tops of Florida thunderstorms in August/September 2009. The plane passed within 10 km horizontal distance of 1213 lightning discharges and only once detected a TGF. If these discharges had produced TGFs of the same intensity as those seen from space, ever...

  9. Synthesis of Volumetric Ring Antenna Array for Terrestrial Coverage Pattern

    Directory of Open Access Journals (Sweden)

    Alberto Reyna

    2014-01-01

    Full Text Available This paper presents a synthesis of a volumetric ring antenna array for a terrestrial coverage pattern. This synthesis regards the spacing among the rings on the planes X-Y, the positions of the rings on the plane X-Z, and uniform and concentric excitations. The optimization is carried out by implementing the particle swarm optimization. The synthesis is compared with previous designs by resulting with proper performance of this geometry to provide an accurate coverage to be applied in satellite applications with a maximum reduction of the antenna hardware as well as the side lobe level reduction.

  10. Ionospheric effects on terrestrial communications: Working Group 3 overview

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan; Bourdillon, A.

    2004-01-01

    Roč. 47, 2/3 (2004), s. 1269-1277 ISSN 1593-5213. [Final Meeting COST271 Action. Effects of the upper atmosphere on terrestrial and Earth-space communications (EACOS). Abingdon, 26.08.2004-27.08.2004] R&D Projects: GA MŠk OC 271.10; GA AV ČR IBS3012007 Institutional research plan: CEZ:AV0Z3042911 Keywords : ionospheric reflection * telecommunications * gravity waves * planetary waves Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 0.413, year: 2004 http://www.annalsofgeophysics.eu/index.php/annals/article/view/3299/3345

  11. Analogue to Digital and Digital to Analogue (AD/DA) Conversion Techniques: An Overview

    CERN Multimedia

    CERN. Geneva

    2002-01-01

    The basic ideas behind modern Analogue to Digital and Digital to Analogue (AD/DA) conversion methods will be introduced: a general view of the importance of these devices will be given, along with the digital representation of time-varying, real-world analogue signals. Some CERN applications will be outlined. The variety of conversion methods, their limitations, error sources and measurement methods will form the major part of this presentation. A review of the technological progress in this field over the last 30 years will be presented, concluding with the present 'state of the art' and a quick look at what is just around the corner. This Technical Training Seminar is in the framework of the FEED-2002 Lecture Series, and it is a prerequisite to attending to any of the FEED-2002 Terms. FEED-2002 is a two-term course that will review the techniques dealing with closed loop systems, focussing on time-invariant linear systems. (free attendance, no registration required) More information on the FEED-2002 ...

  12. Analogues of uracil nucleosides with intrinsic fluorescence (NIF-analogues): synthesis and photophysical properties.

    Science.gov (United States)

    Segal, Meirav; Fischer, Bilha

    2012-02-28

    Uridine cannot be utilized as fluorescent probe due to its extremely low quantum yield. For improving the uracil fluorescence characteristics we extended the natural chromophore at the C5 position by coupling substituted aromatic rings directly or via an alkenyl or alkynyl linker to create fluorophores. Extension of the uracil base was achieved by treating 5-I-uridine with the appropriate boronic acid under the Suzuki coupling conditions. Analogues containing an alkynyl linker were obtained from 5-I-uridine and the suitable boronic acid in a Sonogashira coupling reaction. The uracil fluorescent analogues proposed here were designed to satisfy the following requirements: a minimal chemical modification at a position not involved in base-pairing, resulting in relatively long absorption and emission wavelengths and high quantum yield. 5-((4-Methoxy-phenyl)-trans-vinyl)-2'-deoxy-uridine, 6b, was found to be a promising fluorescent probe. Probe 6b exhibits a quantum yield that is 3000-fold larger than that of the natural chromophore (Φ 0.12), maximum emission (478 nm) which is 170 nm red shifted as compared to uridine, and a Stokes shift of 143 nm. In addition, since probe 6b adopts the anti conformation and S sugar puckering favored by B-DNA, it makes a promising nucleoside analogue to be incorporated in an oligonucleotide probe for detection of genetic material.

  13. Marine Isotope Stage 11: Palaeoclimates, palaeoenvironments and its role as an analogue for the current interglacial

    Science.gov (United States)

    Candy, Ian; Schreve, Danielle C.; Sherriff, Jennifer; Tye, Gareth J.

    2014-01-01

    Interglacials of the Quaternary Period are currently the focus of a great deal of attention within the scientific community. This is primarily because they play a vital role in distinguishing between "natural" and "human" climate change in the current interglacial and in understanding how the Holocene would evolve in the absence of anthropogenic greenhouse warming. In this respect, Marine Isotope Stage 11 (MIS 11, ca 410,000 yr BP) is one of the key interglacial stages of the past 450,000 yr. The pattern of insolation variability that occurs during MIS 11 matches that which occurs in the Holocene more closely than in any other warm stage of the past half a million years. In addition there is now an extensive range of evidence for MIS 11 palaeoclimates and palaeoenvironments from marine, ice core, lacustrine and terrestrial sequences. The aim of this paper is to provide a comprehensive review of the current state of our understanding of MIS 11. This is the first paper to provide a detailed review of MIS 11 that incorporates the wide range of marine, ice core, long lacustrine and terrestrial records that have been generated over the last ten years since the last major overview. Crucially, it is the first review of MIS 11 that incorporates a detailed synthesis of the high-resolution terrestrial sequences of western and central Europe. This paper, therefore, provides a holistic integration of a diverse range of proxies and archives to provide a detailed understanding of the expression of MIS 11 in the Earth system. In particular the review focuses on: (1) the climatic background of MIS 11, (2) the robustness of the identification of MIS 11 in a diverse range of sequences, (3) the climatic structure of MIS 11, (4) the magnitude of warmth that occurred in this warm stage, (5) MIS 11 sea level magnitude and variability, (6) the duration of MIS 11, (7) evidence for abrupt climatic events within the interglacial of MIS 11 and (8) precipitation patterns and trends during

  14. Low earth orbit satellite/terrestrial mobile service compatibility

    Science.gov (United States)

    Sheriff, R. E.; Gardiner, J. G.

    Digital cellular mobile 'second generation' systems are now gradually being introduced into service; one such example is GSM, which will provide a digital voice and data service throughout Europe. Total coverage is not expected to be achieved until the mid '90's, which has resulted in several proposals for the integration of GSM with a geostationary satellite service. Unfortunately, because terrestrial and space systems have been designed to optimize their performance for their particular environment, integration between a satellite and terrestrial system is unlikely to develop further than the satellite providing a back-up service. This lack of system compatibility is now being addressed by system designers of third generation systems. The next generation of mobile systems, referred to as FPLMTS (future public land mobile telecommunication systems) by CCIR and UMTS (universal mobile telecommunication system) in European research programs, are intended to provide inexpensive, hand-held terminals that can operate in either satellite, cellular, or cordless environments. This poses several challenges for system designers, not least in terms of the choice of multiple access technique and power requirements. Satellite mobile services have been dominated by the geostationary orbital type. Recently, however, a number of low earth orbit configurations have been proposed, for example Iridium. These systems are likely to be fully operational by the turn of the century, in time for the implementation of FPLMTS. The developments in LEO mobile satellite service technology were recognized at WARC-92 with the allocation of specific frequency bands for 'big' LEO's, as well as a frequency allocation for FPLMTS which included a specific satellite allocation. When considering integrating a space service into the terrestrial network, LEO's certainly appear to have their attractions: they can provide global coverage, the round trip delay is of the order of tens of milliseconds, and

  15. A molecular palaeobiological exploration of arthropod terrestrialization

    Science.gov (United States)

    Carton, Robert; Edgecombe, Gregory D.

    2016-01-01

    Understanding animal terrestrialization, the process through which animals colonized the land, is crucial to clarify extant biodiversity and biological adaptation. Arthropoda (insects, spiders, centipedes and their allies) represent the largest majority of terrestrial biodiversity. Here we implemented a molecular palaeobiological approach, merging molecular and fossil evidence, to elucidate the deepest history of the terrestrial arthropods. We focused on the three independent, Palaeozoic arthropod terrestrialization events (those of Myriapoda, Hexapoda and Arachnida) and showed that a marine route to the colonization of land is the most likely scenario. Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record, Myriapoda are inferred to have colonized land earlier, substantially predating trace or body fossil evidence. An estimated origin of myriapods by the Early Cambrian precedes the appearance of embryophytes and perhaps even terrestrial fungi, raising the possibility that terrestrialization had independent origins in crown-group myriapod lineages, consistent with morphological arguments for convergence in tracheal systems. This article is part of the themed issue ‘Dating species divergences using rocks and clocks’. PMID:27325830

  16. Steroidal saponins from Tribulus terrestris.

    Science.gov (United States)

    Kang, Li-Ping; Wu, Ke-Lei; Yu, He-Shui; Pang, Xu; Liu, Jie; Han, Li-Feng; Zhang, Jie; Zhao, Yang; Xiong, Cheng-Qi; Song, Xin-Bo; Liu, Chao; Cong, Yu-Wen; Ma, Bai-Ping

    2014-11-01

    Sixteen steroidal saponins, including seven previously unreported compounds, were isolated from Tribulus terrestris. The structures of the saponins were established using 1D and 2D NMR spectroscopy, mass spectrometry, and chemical methods. They were identified as: 26-O-β-d-glucopyranosyl-(25R)-furost-4-en-2α,3β,22α,26-tetrol-12-one (terrestrinin C), 26-O-β-d-glucopyranosyl-(25R)-furost-4-en-22α,26-diol-3,12-dione (terrestrinin D), 26-O-β-d-glucopyranosyl-(25S)-furost-4-en-22α,26-diol-3,6,12-trione (terrestrinin E), 26-O-β-d-glucopyranosyl-(25R)-5α-furostan-3β,22α,26-triol-12-one (terrestrinin F), 26-O-β-d-glucopyranosyl-(25R)-furost-4-en-12β,22α,26-triol-3-one (terrestrinin G), 26-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranosyl-(25R)-furost-4-en-22α,26-diol-3,12-dione (terrestrinin H), and 24-O-β-d-glucopyranosyl-(25S)-5α-spirostan-3β,24β-diol-12-one-3-O-β-d-glucopyranosyl-(1→4)-β-d-galactopyranoside (terrestrinin I). The isolated compounds were evaluated for their platelet aggregation activities. Three of the known saponins exhibited strong effects on the induction of platelet aggregation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. The Circumpolar Biodiversity Monitoring Program Terrestrial Plan

    DEFF Research Database (Denmark)

    Christensen, Tom; Payne, J.; Doyle, M.

    and coastal environments. The CBMP Terrestrial Plan is a framework to focus and coordinate monitoring of terrestrial biodiversity across the Arctic. The goal of the plan is to improve the collective ability of Arctic traditional knowledge (TK) holders, northern communities, and scientists to detect......The Conservation of Arctic Flora and Fauna (CAFF), the biodiversity working group of the Arctic Council, established the Circumpolar Biodiversity Monitoring Program (CBMP) to address the need for coordinated and standardized monitoring of Arctic environments in terrestrial, marine, freshwater...

  18. The Greenland Analogue Project. Yearly Report 2009

    International Nuclear Information System (INIS)

    2010-12-01

    A deep geological repository for spent nuclear fuel needs to be designed to keep used nuclear fuel isolated from mankind and the environment for a million years. Within this time frame glacial conditions are expected in regions that have been glaciated in the past two to ten million years. Climate induced changes such as the growth of ice sheets and permafrost will influence and alter the ground surface and subsurface environment, including its hydrology, which may impact repository safety. Glaciation impact assessments have to-date used over-simplified models and conservative assumptions, for example in the representation of ice sheet hydrology, that do not reflect the complexity of natural systems and processes. This is largely due to lack of direct observations of such processes from existing ice sheets, which if more readily available could help reduce uncertainties and provide a strong scientific basis for the treatment of glacial impacts in safety assessments. Our current understanding of the hydrological, hydrogeological and hydrogeochemical processes associated with glacial cycles and their impact on the long-term performance of deep geological repositories for spent nuclear fuel will be significantly improved by studying a modern analogue. To advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository, the Greenland Analogue Project (GAP), a four-year field and modelling study of the Greenland ice sheet and sub-surface conditions, has been initiated collaboratively by SKB, Posiva and NWMO. The study site encompasses a land terminus portion of the Greenland ice sheet east of Kangerlussuaq and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project is planned to run from 2009 until 2012. The GAP will conduct the first in situ investigations of some of

  19. The Greenland Analogue Project. Yearly Report 2009

    Energy Technology Data Exchange (ETDEWEB)

    2010-12-15

    A deep geological repository for spent nuclear fuel needs to be designed to keep used nuclear fuel isolated from mankind and the environment for a million years. Within this time frame glacial conditions are expected in regions that have been glaciated in the past two to ten million years. Climate induced changes such as the growth of ice sheets and permafrost will influence and alter the ground surface and subsurface environment, including its hydrology, which may impact repository safety. Glaciation impact assessments have to-date used over-simplified models and conservative assumptions, for example in the representation of ice sheet hydrology, that do not reflect the complexity of natural systems and processes. This is largely due to lack of direct observations of such processes from existing ice sheets, which if more readily available could help reduce uncertainties and provide a strong scientific basis for the treatment of glacial impacts in safety assessments. Our current understanding of the hydrological, hydrogeological and hydrogeochemical processes associated with glacial cycles and their impact on the long-term performance of deep geological repositories for spent nuclear fuel will be significantly improved by studying a modern analogue. To advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository, the Greenland Analogue Project (GAP), a four-year field and modelling study of the Greenland ice sheet and sub-surface conditions, has been initiated collaboratively by SKB, Posiva and NWMO. The study site encompasses a land terminus portion of the Greenland ice sheet east of Kangerlussuaq and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project is planned to run from 2009 until 2012. The GAP will conduct the first in situ investigations of some of

  20. Medical judgement analogue studies with applications to spaceflight crew medical officer.

    Science.gov (United States)

    McCarroll, Michele L; Ahmed, Rami A; Schwartz, Alan; Gothard, Michael David; Atkinson, Steven Scott; Hughes, Patrick; Brito, Jose Cepeda; Assad, Lori; Myers, Jerry; George, Richard L

    2017-10-01

    The National Aeronautics and Space Administration (NASA) developed plans for potential emergency conditions from the Exploration Medical Conditions List. In an effort to mitigate conditions on the Exploration Medical Conditions List, NASA implemented a crew medical officer (CMO) designation for eligible astronauts. This pilot study aims to add knowledge that could be used in the Integrated Medical Model. An analogue population was recruited for two categories: administrative physicians (AP) representing the physician CMOs and technical professionals (TP) representing the non-physician CMOs. Participants completed four medical simulations focused on abdominal pain: cholecystitis (CH) and renal colic (RC) and chest pain: cardiac ischaemia (STEMI; ST-segment elevation myocardial infarction) and pneumothorax (PX). The Medical Judgment Metric (MJM) was used to evaluate medical decision making. There were no significant differences between the AP and TP groups in age, gender, race, ethnicity, education and baseline heart rate. Significant differences were noted in MJM average rater scores in AP versus TP in CH: 13.0 (±2.25), 4.5 (±0.48), p=medical judgement between the two analogue groups of spaceflight CMOs. Future studies should incorporate the MJM in a larger analogue population study to assess the medical risk for spaceflight crewmembers.

  1. Ultrasound in Space Medicine

    Science.gov (United States)

    Dulchavsky, Scott A.; Sargsyan, A.E.

    2009-01-01

    This slide presentation reviews the use of ultrasound as a diagnostic tool in microgravity environments. The goals of research in ultrasound usage in space environments are: (1) Determine accuracy of ultrasound in novel clinical conditions. (2) Determine optimal training methodologies, (3) Determine microgravity associated changes and (4) Develop intuitive ultrasound catalog to enhance autonomous medical care. Also uses of Ultrasound technology in terrestrial applications are reviewed.

  2. On Separation Axioms in an Ordered Neutrosophic Bitopological Space

    Directory of Open Access Journals (Sweden)

    R. Narmada Devi

    2017-12-01

    Full Text Available In this paper we introduce the concept of a new class of an ordered neutrosophic bitopological spaces. Besides giving some interesting properties of these spaces. We also prove analogues of Uryshon’s lemma and Tietze extension theorem in an ordered neutrosophic bitopological spaces.

  3. Joint control of terrestrial gross primary productivity by plant phenology and physiology

    NARCIS (Netherlands)

    Xia, J.; Niu, S.; Ciais, P.; Janssens, I.A.; Chen, J.; Ammann, C.; Arain, A.; Blanken, P.D.; Cescatti, A.; Moors, E.J.

    2015-01-01

    Terrestrial gross primary productivity (GPP) varies greatly over time and space. A better understanding of this variability is necessary for more accurate predictions of the future climate–carbon cycle feedback. Recent studies have suggested that variability in GPP is driven by a broad range of

  4. Terrestrial teleconnections link global rivers

    Science.gov (United States)

    O'Loughlin, F.; Howden, N. J.; Woods, R. A.; Bates, P. D.

    2013-12-01

    . Aside from these practical applications, the results also suggest teleconnections exist between terrestrial, as well as ocean and atmospheric water systems.

  5. Durable terrestrial bedrock predicts submarine canyon formation

    Science.gov (United States)

    Smith, Elliot; Finnegan, Noah J.; Mueller, Erich R.; Best, Rebecca J.

    2017-01-01

    Though submarine canyons are first-order topographic features of Earth, the processes responsible for their occurrence remain poorly understood. Potentially analogous studies of terrestrial rivers show that the flux and caliber of transported bedload are significant controls on bedrock incision. Here we hypothesize that coarse sediment load could exert a similar role in the formation of submarine canyons. We conducted a comprehensive empirical analysis of canyon occurrence along the West Coast of the contiguous United States which indicates that submarine canyon occurrence is best predicted by the occurrence of durable crystalline bedrock in adjacent terrestrial catchments. Canyon occurrence is also predicted by the flux of bed sediment to shore from terrestrial streams. Surprisingly, no significant correlation was observed between canyon occurrence and the slope or width of the continental shelf. These findings suggest that canyon incision is promoted by greater yields of durable terrestrial clasts to the shore.

  6. Durable Terrestrial Bedrock Predicts Submarine Canyon Formation

    Science.gov (United States)

    Smith, M. Elliot; Finnegan, Noah J.; Mueller, Erich R.; Best, Rebecca J.

    2017-10-01

    Though submarine canyons are first-order topographic features of Earth, the processes responsible for their occurrence remain poorly understood. Potentially analogous studies of terrestrial rivers show that the flux and caliber of transported bedload are significant controls on bedrock incision. Here we hypothesize that coarse sediment load could exert a similar role in the formation of submarine canyons. We conducted a comprehensive empirical analysis of canyon occurrence along the West Coast of the contiguous United States which indicates that submarine canyon occurrence is best predicted by the occurrence of durable crystalline bedrock in adjacent terrestrial catchments. Canyon occurrence is also predicted by the flux of bed sediment to shore from terrestrial streams. Surprisingly, no significant correlation was observed between canyon occurrence and the slope or width of the continental shelf. These findings suggest that canyon incision is promoted by greater yields of durable terrestrial clasts to the shore.

  7. UK Natural Analogue Coordinating Group: fourth annual report

    International Nuclear Information System (INIS)

    Read, D.; Hooker, P.J.

    1992-01-01

    HMIP has a research programme investigating some naturally radioactive sites as geochemical analogues of radionuclide migration. All of the analogue sites under investigation, both in the U.K. and overseas, are located where elevated uranium concentrations occur naturally. Coordination of the programme is achieved through the UK Natural Analogue Co-ordinating Group (NACG) which has met three times in this reporting period. The NACG is steered by the British Geological Survey. Its purpose is to ensure that the different research projects have an integrated function aimed at increasing our understanding of natural geochemical processes. Effort is also being expended in testing research models which may be used in such assessments. (author)

  8. A chemoselective and continuous synthesis of m-sulfamoylbenzamide analogues

    Directory of Open Access Journals (Sweden)

    Arno Verlee

    2017-02-01

    Full Text Available For the synthesis of m-sulfamoylbenzamide analogues, small molecules which are known for their bioactivity, a chemoselective procedure has been developed starting from m-(chlorosulfonylbenzoyl chloride. Although a chemoselective process in batch was already reported, a continuous-flow process reveals an increased selectivity at higher temperatures and without catalysts. In total, 15 analogues were synthesized, using similar conditions, with yields ranging between 65 and 99%. This is the first automated and chemoselective synthesis of m-sulfamoylbenzamide analogues.

  9. A Low-cost Multi-channel Analogue Signal Generator

    CERN Document Server

    Müller, F; The ATLAS collaboration; Shen, W; Stamen, R

    2009-01-01

    A scalable multi-channel analogue signal generator is presented. It uses a commercial low-cost graphics card with multiple outputs in a standard PC as signal source. Each color signal serves as independent channel to generate an analogue signal. A custom-built external PCB was developed to adjust the graphics card output voltage levels for a specific task, which needed differential signals. The system furthermore comprises a software package to program the signal shape. The signal generator was successfully used as independent test bed for the ATLAS Level-1 Trigger Pre-Processor, providing up to 16 analogue signals.

  10. Long-term predictions using natural analogues

    International Nuclear Information System (INIS)

    Ewing, R.C.

    1995-01-01

    One of the unique and scientifically most challenging aspects of nuclear waste isolation is the extrapolation of short-term laboratory data (hours to years) to the long time periods (10 3 -10 5 years) required by regulatory agencies for performance assessment. The direct validation of these extrapolations is not possible, but methods must be developed to demonstrate compliance with government regulations and to satisfy the lay public that there is a demonstrable and reasonable basis for accepting the long-term extrapolations. Natural systems (e.g., open-quotes natural analoguesclose quotes) provide perhaps the only means of partial open-quotes validation,close quotes as well as data that may be used directly in the models that are used in the extrapolation. Natural systems provide data on very large spatial (nm to km) and temporal (10 3 -10 8 years) scales and in highly complex terranes in which unknown synergisms may affect radionuclide migration. This paper reviews the application (and most importantly, the limitations) of data from natural analogue systems to the open-quotes validationclose quotes of performance assessments

  11. Parallel Computing for Terrestrial Ecosystem Carbon Modeling

    International Nuclear Information System (INIS)

    Wang, Dali; Post, Wilfred M.; Ricciuto, Daniel M.; Berry, Michael

    2011-01-01

    Terrestrial ecosystems are a primary component of research on global environmental change. Observational and modeling research on terrestrial ecosystems at the global scale, however, has lagged behind their counterparts for oceanic and atmospheric systems, largely because the unique challenges associated with the tremendous diversity and complexity of terrestrial ecosystems. There are 8 major types of terrestrial ecosystem: tropical rain forest, savannas, deserts, temperate grassland, deciduous forest, coniferous forest, tundra, and chaparral. The carbon cycle is an important mechanism in the coupling of terrestrial ecosystems with climate through biological fluxes of CO 2 . The influence of terrestrial ecosystems on atmospheric CO 2 can be modeled via several means at different timescales. Important processes include plant dynamics, change in land use, as well as ecosystem biogeography. Over the past several decades, many terrestrial ecosystem models (see the 'Model developments' section) have been developed to understand the interactions between terrestrial carbon storage and CO 2 concentration in the atmosphere, as well as the consequences of these interactions. Early TECMs generally adapted simple box-flow exchange models, in which photosynthetic CO 2 uptake and respiratory CO 2 release are simulated in an empirical manner with a small number of vegetation and soil carbon pools. Demands on kinds and amount of information required from global TECMs have grown. Recently, along with the rapid development of parallel computing, spatially explicit TECMs with detailed process based representations of carbon dynamics become attractive, because those models can readily incorporate a variety of additional ecosystem processes (such as dispersal, establishment, growth, mortality etc.) and environmental factors (such as landscape position, pest populations, disturbances, resource manipulations, etc.), and provide information to frame policy options for climate change

  12. Topics in Banach space theory

    CERN Document Server

    Albiac, Fernando

    2016-01-01

    This text provides the reader with the necessary technical tools and background to reach the frontiers of research without the introduction of too many extraneous concepts. Detailed and accessible proofs are included, as are a variety of exercises and problems. The two new chapters in this second edition are devoted to two topics of much current interest amongst functional analysts: Greedy approximation with respect to bases in Banach spaces and nonlinear geometry of Banach spaces. This new material is intended to present these two directions of research for their intrinsic importance within Banach space theory, and to motivate graduate students interested in learning more about them. This textbook assumes only a basic knowledge of functional analysis, giving the reader a self-contained overview of the ideas and techniques in the development of modern Banach space theory. Special emphasis is placed on the study of the classical Lebesgue spaces Lp (and their sequence space analogues) and spaces of continuous f...

  13. Approximation by q-analogue of modified Jakimovski-Leviatan-Stancu type operators

    Directory of Open Access Journals (Sweden)

    Mursaleen Mohammad

    2017-04-01

    Full Text Available In this paper, we introduce the q-analogue of the Jakimovski-Leviatan type modified operators introduced by Atakut with the help of the q-Appell polynomials.We obtain some approximation results via the well-known Korovkin’s theorem for these operators.We also study convergence properties by using the modulus of continuity and the rate of convergence of the operators for functions belonging to the Lipschitz class. Moreover,we study the rate of convergence in terms of modulus of continuity of these operators in aweighted space.

  14. Anthropogenic transformation of the terrestrial biosphere.

    Science.gov (United States)

    Ellis, Erle C

    2011-03-13

    Human populations and their use of land have transformed most of the terrestrial biosphere into anthropogenic biomes (anthromes), causing a variety of novel ecological patterns and processes to emerge. To assess whether human populations and their use of land have directly altered the terrestrial biosphere sufficiently to indicate that the Earth system has entered a new geological epoch, spatially explicit global estimates of human populations and their use of land were analysed across the Holocene for their potential to induce irreversible novel transformation of the terrestrial biosphere. Human alteration of the terrestrial biosphere has been significant for more than 8000 years. However, only in the past century has the majority of the terrestrial biosphere been transformed into intensively used anthromes with predominantly novel anthropogenic ecological processes. At present, even were human populations to decline substantially or use of land become far more efficient, the current global extent, duration, type and intensity of human transformation of ecosystems have already irreversibly altered the terrestrial biosphere at levels sufficient to leave an unambiguous geological record differing substantially from that of the Holocene or any prior epoch. It remains to be seen whether the anthropogenic biosphere will be sustained and continue to evolve.

  15. Linking animals aloft with the terrestrial landscape

    Science.gov (United States)

    Buler, Jeffrey J.; Barrow, Wylie; Boone, Matthew; Dawson, Deanna K.; Diehl, Robert H.; Moore, Frank R.; Randall, Lori A.; Schreckengost, Timothy; Smolinsky, Jaclyn A.

    2018-01-01

    Despite using the aerosphere for many facets of their life, most flying animals (i.e., birds, bats, some insects) are still bound to terrestrial habitats for resting, feeding, and reproduction. Comprehensive broad-scale observations by weather surveillance radars of animals as they leave terrestrial habitats for migration or feeding flights can be used to map their terrestrial distributions either as point locations (e.g., communal roosts) or as continuous surface layers (e.g., animal densities in habitats across a landscape). We discuss some of the technical challenges to reducing measurement biases related to how radars sample the aerosphere and the flight behavior of animals. We highlight a recently developed methodological approach that precisely and quantitatively links the horizontal spatial structure of birds aloft to their terrestrial distributions and provides novel insights into avian ecology and conservation across broad landscapes. Specifically, we present case studies that (1) elucidate how migrating birds contend with crossing ecological barriers and extreme weather events, (2) identify important stopover areas and habitat use patterns of birds along their migration routes, and (3) assess waterfowl response to wetland habitat management and restoration. These studies aid our understanding of how anthropogenic modification of the terrestrial landscape (e.g., urbanization, habitat management), natural geographic features, and weather (e.g., hurricanes) can affect the terrestrial distributions of flying animals.

  16. Abiogenic synthesis on terrestrial orbit

    Science.gov (United States)

    Simakov, Michael B.; Kuzicheva, Evgenia; Gontareva, Natalia

    Meteorites probably played a central role in the evolution of life. Due to the structure, they tend to adsorb organic compounds and catalyze a variety of organic reactions critical to scenarios of life’s origins. We have shown experimentally that extraterrestrial minerals can catalyze the formation of peptides and nucleotides. The present study was performed onboard different Russian space stations (BION, COSMOS, and MIR) with various duration, altitude, and radiation conditions. Irradiation of solid samples, free or admixed with certain minerals, was the major task of future space flight experiments, planned for performing onboard Russian space satellite Bion-M. The «simulated space ice conditions» experiments have shown the synthesis of simple biochemical compounds in the form of amino acid’s precursors and pyrimidine bases (uracil, cyrosine and thymine) of the nucleic acids. Our investigation dealt with further reaction of nucleic acid components to nucleotides - main components of RNA and DNA, and single aminoacids to oligopeptides. We investigated two types of reactions: (1) abiogenic synthesis of nucleotides from mixtures of nucleoside + inorganic phosphate; (2) abiogenic synthesis of dipeptides from mixtures of simple amino acids. The reaction mixture in the form of a solid film contains (1) nucleoside and dihydrogen phosphate; (2) two different amino acids. Seven different nucleosides (thymidine, cytidine, uracil, adenosine or deoxyadenosine, guanosine or deoxyguanosine) and four mixtures of aromatic (tyrosine or triptophan) and aliphatic (glycine or alanine) amino acids were investigated. Mixtures were irradiated as solid films with different sources of energy: (1) VUV-light of 145 nm; (2) high energy protons (2-6 MeV); and (3) were installed on the surface of biosputnik in outstanding container when they were exposed to the action of all spectra of the open space energy sources during the entire time of flight. We have shown experimentally that the

  17. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2011-01-01

    Most people think of groundwater as a resource, but it is also a useful indicator of climate variability and human impacts on the environment. Groundwater storage varies slowly relative to other non-frozen components of the water cycle, encapsulating long period variations and trends in surface meteorology. On seasonal to interannual timescales, groundwater is as dynamic as soil moisture, and it has been shown that groundwater storage changes have contributed to sea level variations. Groundwater monitoring well measurements are too sporadic and poorly assembled outside of the United States and a few other nations to permit direct global assessment of groundwater variability. However, observational estimates of terrestrial water storage (TWS) variations from the GRACE satellites largely represent groundwater storage variations on an interannual basis, save for high latitude/altitude (dominated by snow and ice) and wet tropical (surface water) regions. A figure maps changes in mean annual TWS from 2009 to 2010, based on GRACE, reflecting hydroclimatic conditions in 2010. Severe droughts impacted Russia and the Amazon, and drier than normal weather also affected the Indochinese peninsula, parts of central and southern Africa, and western Australia. Groundwater depletion continued in northern India, while heavy rains in California helped to replenish aquifers that have been depleted by drought and withdrawals for irrigation, though they are still below normal levels. Droughts in northern Argentina and western China similarly abated. Wet weather raised aquifer levels broadly across western Europe. Rains in eastern Australia caused flooding to the north and helped to mitigate a decade long drought in the south. Significant reductions in TWS seen in the coast of Alaska and the Patagonian Andes represent ongoing glacier melt, not groundwater depletion. Figures plot time series of zonal mean and global GRACE derived non-seasonal TWS anomalies (deviation from the mean of

  18. Solistatinol, a novel phenolic compactin analogue from Penicillium solitum

    DEFF Research Database (Denmark)

    Larsen, Thomas Ostenfeld; Lange, Lene; Schnorr, Kirk

    2007-01-01

    Solistatinol, a novel phenolic compactin analogue, has been isolated from Penicillium solitum using a UV-guided strategy. The structure and relative stereochemistry were determined by NMR spectroscopy and mass spectrometry. The absolute stereochemistry was determined by chemical degradation...

  19. Heterocyclic Analogues of Modafinil as Novel, Atypical Dopamine Transporter Inhibitors.

    Science.gov (United States)

    Kalaba, Predrag; Aher, Nilima Y; Ilić, Marija; Dragačević, Vladimir; Wieder, Marcus; Miklosi, Andras G; Zehl, Martin; Wackerlig, Judith; Roller, Alexander; Beryozkina, Tetyana; Radoman, Bojana; Saroja, Sivaprakasam R; Lindner, Wolfgang; Gonzalez, Eduardo Perez; Bakulev, Vasiliy; Leban, Johann Jakob; Sitte, Harald H; Urban, Ernst; Langer, Thierry; Lubec, Gert

    2017-11-22

    Modafinil is a wake promoting compound with high potential for cognitive enhancement. It is targeting the dopamine transporter (DAT) with moderate selectivity, thereby leading to reuptake inhibition and increased dopamine levels in the synaptic cleft. A series of modafinil analogues have been reported so far, but more target-specific analogues remain to be discovered. It was the aim of this study to synthesize and characterize such analogues and, indeed, a series of compounds were showing higher activities on the DAT and a higher selectivity toward DAT versus serotonin and norepinephrine transporters than modafinil. This was achieved by substituting the amide moiety by five- and six-membered aromatic heterocycles. In vitro studies indicated binding to the cocaine pocket on DAT, although molecular dynamics revealed binding different from that of cocaine. Moreover, no release of dopamine was observed, ruling out amphetamine-like effects. The absence of neurotoxicity of a representative analogue may encourage further preclinical studies of the above-mentioned compounds.

  20. Trustworthiness and Influence: A Reexamination in an Extended Counseling Analogue.

    Science.gov (United States)

    Rothmeier, Rosemarie C.; Dixon, David N.

    1980-01-01

    The study demonstrated that: (1) interviewer trustworthiness can be manipulated in an analogue interview setting; and (2) interviewer trustworthiness is related to interpersonal influence in the interview setting. Findings follow a pattern of outcomes predicted by cognitive dissonance theory. (Author)

  1. Synthesis and antifungal activity of two novel spermidine analogues.

    Science.gov (United States)

    Mackintosh, C A; Slater, L A; McClintock, C A; Walters, D R; Havis, N D; Robins, D J

    1997-03-01

    Two spermidine analogues were synthesised and examined for antifungal activity. Both compounds used as 1 mM post-inoculation sprays reduced infection of barley seedlings by the powdery mildew fungus, Erysiphe graminis f.sp. hordei, infection of broad bean seedlings by the rust fungus, Uromyces viciae-fabae, and infection of apple seedlings by the powdery mildew fungus, Podosphaera leucotricha. Since these fungal pathogens cannot be cultured axenically, the effects of the two spermidine analogues on mycelial growth in vitro, as well as preliminary investigations on polyamine biosynthesis, were undertaken using the oat stripe pathogen, Pyrenophora avenae. Although neither compound affected radial growth of the fungus on plates, both analogues reduced fungal biomass in liquid culture substantially. The two spermidine analogues, used at a concentration of 1 mM, had no significant effect on the conversion of labelled ornithine into polyamines in P. avenae.

  2. Current prodrug strategies for improving oral absorption of nucleoside analogues

    Directory of Open Access Journals (Sweden)

    Youxi Zhang

    2014-04-01

    Full Text Available Nucleoside analogues are first line chemotherapy in various severe diseases: AIDS (acquired immunodeficiency disease syndrome, cytomegalovirus infections, cancer, etc. However, many nucleoside analogues exhibit poor oral bioavailability because of their high polarity and low intestinal permeability. In order to get around this drawback, prodrugs have been utilized to improve lipophilicity by chemical modification of the parent drug. Alternatively, prodrugs targeting transporters present in the intestine have been applied to promote the transport of the nucleoside analogues. Valacyclovir and valganciclovir are two classic valine ester prodrugs transported by oligopeptide transporter 1. The ideal prodrug achieves delivery of a parent drug by attaching a non-toxic moiety that is stable during transport, but is readily degraded to the parent drug once at the target. This article presents advances of prodrug approaches for enhancing oral absorption of nucleoside analogues.

  3. Insulin analogues in pregnancy and specific congenital anomalies

    DEFF Research Database (Denmark)

    de Jong, Josta; Garne, Ester; Wender-Ozegowska, Ewa

    2016-01-01

    women with pregestational diabetes using insulin analogues in the first trimester and information on congenital anomalies. The studies were analysed to compare the congenital anomaly rate among foetuses of mothers using insulin analogues with foetuses of mothers using human insulin. Of 29 studies, we...... included 1286 foetuses of mothers using short-acting insulin analogues with 1089 references of mothers using human insulin and 768 foetuses of mothers using long-acting insulin analogues with 685 references of mothers using long-acting human insulin (Neutral Protamine Hagedorn). The congenital anomaly rate...... was 4.84% and 4.29% among the foetuses of mothers using lispro and aspart. For glargine and detemir, the congenital anomaly rate was 2.86% and 3.47%, respectively. No studies on the use of insulin glulisine and degludec in pregnancy were found. There was no statistically significant difference...

  4. Analogue Signal Processing: Collected Papers 1996-97

    DEFF Research Database (Denmark)

    1997-01-01

    This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of the Department of Information Technology, Technical University of Denmark, in 1996 and 1997....

  5. Extra-terrestrial construction processes - Advancements, opportunities and challenges

    Science.gov (United States)

    Lim, Sungwoo; Prabhu, Vibha Levin; Anand, Mahesh; Taylor, Lawrence A.

    2017-10-01

    Government space agencies, including NASA and ESA, are conducting preliminary studies on building alternative space-habitat systems for deep-space exploration. Such studies include development of advanced technologies for planetary surface exploration, including an in-depth understanding of the use of local resources. Currently, NASA plans to land humans on Mars in the 2030s. Similarly, other space agencies from Europe (ESA), Canada (CSA), Russia (Roscosmos), India (ISRO), Japan (JAXA) and China (CNSA) have already initiated or announced their plans for launching a series of lunar missions over the next decade, ranging from orbiters, landers and rovers for extended stays on the lunar surface. As the Space Odyssey is one of humanity's oldest dreams, there has been a series of research works for establishing temporary or permanent settlement on other planetary bodies, including the Moon and Mars. This paper reviews current projects developing extra-terrestrial construction, broadly categorised as: (i) ISRU-based construction materials; (ii) fabrication methods; and (iii) construction processes. It also discusses four categories of challenges to developing an appropriate construction process: (i) lunar simulants; (ii) material fabrication and curing; (iii) microwave-sintering based fabrication; and (iv) fully autonomous and scaled-up construction processes.

  6. Water ice is water ice: some applications and limitations of Earth analogues to Mars

    Science.gov (United States)

    Koutnik, M.; Pathare, A.; Waddington, E. D.; Winebrenner, D. P.

    2017-12-01

    Quantitative and qualitative analyses of ice on Mars have advanced with the acquisition of abundant topography, imagery, and radar data, which have enabled the planetary-science community to tackle sophisticated questions about the martian cryosphere. Over the past decades, many studies have applied knowledge of terrestrial ice-sheet and glacier flow to improve understanding of ice behavior on Mars. A key question for both planets is how we can robustly interpret past climate from glaciological and glacial geomorphological features. Doing this requires deciphering how the history of accumulation, ablation, dust/debris deposition, and flow led to the shape and internal structure of present-day ice. Terrestrial glaciology and glacial geomorphology provide physical relationships that can be extended across environmental conditions to characterize related processes that may act at different rates or on different timescales. However, there remain fundamental unknowns about martian ice rheology and history that often limit our ability to directly apply understanding of ice dynamics learned from Antarctica, Greenland, terrestrial glaciers, and laboratory ice experiments. But the field is rich with opportunity because the constitutive relationship for water ice depends on quantities that can typically be reasonably estimated; water ice is water ice. We reflect on progress to understand the history of the ice-rich North Polar Layered Deposits (NPLD) and of select mid-latitude Lobate Debris Aprons (LDAs), and the utility of terrestrial ice-sheet and glacier analogues for these problems. Our work on Earth and Mars has focused on constraining surface accumulation/ablation patterns and ice-flow histories from topography and radar observations. We present on the challenge of interpreting internal-layer shapes when both accumulation/ablation and ice-flow histories are unknown, and how this non-uniqueness can be broken only by making assumptions about one or the other. In

  7. 3-alkyl fentanyl analogues: Structure-activity-relationship study

    OpenAIRE

    Vučković, Sonja; Savić-Vujović, Katarina; Srebro, Dragana; Ivanović, Milovan; Došen-Mićović, Ljiljana; Stojanović, Radan; Prostran, Milica

    2012-01-01

    Introduction. Fentanyl belongs to 4-anilidopiperidine class of synthetic opioid analgesics. It is characterized by high potency, rapid onset and short duration of action. A large number of fentanyl analogues have been synthesized so far, both to establish the structure-activity-relationship (SAR) and to find novel, clinically useful analgesic drugs. Objective. In this study, newly synthesized 3-alkyl fentanyl analogues were examined for analgesic activity and compared with fentanyl. Methods. ...

  8. Analogue Signal Processing: Collected Papers 1994-95

    DEFF Research Database (Denmark)

    1996-01-01

    This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of Electronics Institute, Technical University of Denmark, in 1994 and 1995.......This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of Electronics Institute, Technical University of Denmark, in 1994 and 1995....

  9. The Greenland Analogue Project, Yearly Report 2009

    International Nuclear Information System (INIS)

    2011-08-01

    To advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository, the Greenland Analogue Project (GAP), a four-year field and modelling study of the Greenland ice sheet and sub-surface conditions, has been initiated collaboratively by SKB, Posiva and NWMO. The study site encompasses a land terminus portion of the Greenland ice sheet east of Kangerlussuaq and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project is planned to run from 2009 until 2012. The GAP will conduct the first in situ investigations of some of the parameters and processes needed to achieve a realistic understanding of how an ice sheet may impact a deep repository, and will provide measurements, observations and data that may significantly improve our safety assessments and risk analyses of glaciation scenarios. The project includes three sub-projects (A-C) with specific individual objectives, which collectively aim at contributing knowledge and input to the overall project aim. Three field campaigns were carried out in SPA during 2009. These campaigns focused on: (1) deployment and maintenance of AWS and GPS stations and to test the deep-look radar equipment; (2) investigating the hydrological processes and feedbacks and testing of passive seismic equipment; (3) downloading of weather station data and GPS data and winterizing the equipment. An extensive archive of real-time satellite remote sensing datasets has been obtained to be able to better constraint the surface elevation and dynamics of basal hydrological mechanisms. From this archive it has been possible to obtain Russell Glacier Cachment (RGC)-wide constraints on annual, seasonal and specific temporal snapshots of surface speed, initial lake and moulin distribution, drainage and network connections along with the temporal

  10. Taking the trophic bypass: aquatic-terrestrial linkage reduces methylmercury in a terrestrial food web.

    Science.gov (United States)

    Bartrons, Mireia; Gratton, Claudio; Spiesman, Brian J; Vander Zanden, M Jake

    2015-01-01

    Ecosystems can be linked by the movement of matter and nutrients across habitat boundaries via aquatic insect emergence. Aquatic organisms tend to have higher concentrations of certain toxic contaminants such as methylmercury (MeHg) compared to their terrestrial counterparts. If aquatic organisms come to land, terrestrial organisms that consume them are expected to have elevated MeHg concentrations. But emergent aquatic insects could have other impacts as well, such as altering consumer trophic position or increasing ecosystem productivity as a result of nutrient inputs from insect carcasses. We measure MeHg in terrestrial arthropods at two lakes in northeastern Iceland and use carbon and nitrogen stable isotopes to quantify aquatic reliance and trophic position. Across all terrestrial focal arthropod taxa (Lycosidae, Linyphiidae, Acari, Opiliones), aquatic reliance had significant direct and indirect (via changes in trophic position) effects on terrestrial consumer MeHg. However, contrary to our expectations, terrestrial consumers that consumed aquatic prey had lower MeHg concentrations than consumers that ate mostly terrestrial prey. We hypothesize that this is due to the lower trophic position of consumers feeding directly on midges relative to those that fed mostly on terrestrial prey and that had, on average, higher trophic positions. Thus, direct consumption of aquatic inputs results in a trophic bypass that creates a shorter terrestrial food web and reduced biomagnification of MeHg across the food web. Our finding that MeHg was lower at terrestrial sites with aquatic inputs runs counter to the conventional wisdom that aquatic systems are a source of MeHg contamination to surrounding terrestrial ecosystems.

  11. SPGD: A central power system for space title in French

    International Nuclear Information System (INIS)

    Widrig, R.D.

    1991-01-01

    This paper describes the Space Power Generation and Distribution (SPGD) concept for providing power to any satellite in earth orbit via power beaming. Other applications such as providing power for terrestrial or space exploration purposes are identified. An assessment of SPGD versus conventional space power is summarized concluding SPGD appears extremely attractive for our space future. 1 ref

  12. Application of natural analogues in the Yucca Mountain project - overview

    International Nuclear Information System (INIS)

    Simmons, Ardyth M.

    2003-01-01

    The Natural Analogue Synthesis Report (NASR) [1] provides a compilation of information from analogues that test, corroborate, and add confidence to process models and model predictions pertinent to total system performance assessment (TSPA). The report updated previous work [2] with new literature examples and results of quantitative studies conducted by the Yucca Mountain Project (YMP). The intent of the natural analogue studies was to collect corroborative evidence from analogues to demonstrate greater understanding of processes expected to occur during postclosure of a proposed Yucca Mountain repository. Natural analogues, as used here, refer to either natural or anthropogenic systems in which processes similar to those expected to occur in a nuclear waste repository are thought to have occurred over long time periods (decades to millenia) and large spatial scales (up to tens of kilometers). In the past, the YMP has used analogues for testing and building confidence in conceptual and numerical process models in a number of ways. Yucca Mountain mineral alteration phases provided a self-analogue for postclosure alteration [3]. Thermodynamic parameters for silica minerals of the Wairakai, New Zealand geothermal field were added to databases used in geochemical modeling [4]. Scoping calculations of radionuclide transport using the Yucca Mountain TSPA numerical model were conducted for the Peqa Blanca site [5]. Eruption parameters from the Cerro Negro volcano, Nicaragua, were used to verify codes that model ash plume dispersion [6]. Analogues have also been used in supplemental science and performance analyses to provide multiple lines of evidence in support of both analyses and model reports (AMRs) [7]; in screening arguments for inclusion or exclusion of features, events, and processes (FEP)s in TSPAs; in the quantification of uncertainties [7]; in expert elicitations of volcanic and seismic hazards [8, 9] and in peer reviews [10]. Natural analogues may be applied

  13. Characterisation of insulin analogues therapeutically available to patients

    KAUST Repository

    Adams, Gary G.

    2018-03-29

    The structure and function of clinical dosage insulin and its analogues were assessed. This included \\'native insulins\\' (human recombinant, bovine, porcine), \\'fast-acting analogues\\' (aspart, glulisine, lispro) and \\'slow-acting analogues\\' (glargine, detemir, degludec). Analytical ultracentrifugation, both sedimentation velocity and equilibrium experiments, were employed to yield distributions of both molar mass and sedimentation coefficient of all nine insulins. Size exclusion chromatography, coupled to multi-angle light scattering, was also used to explore the function of these analogues. On ultracentrifugation analysis, the insulins under investigation were found to be in numerous conformational states, however the majority of insulins were present in a primarily hexameric conformation. This was true for all native insulins and two fast-acting analogues. However, glargine was present as a dimer, detemir was a multi-hexameric system, degludec was a dodecamer (di-hexamer) and glulisine was present as a dimer-hexamer-dihexamer system. However, size-exclusion chromatography showed that the two hexameric fast-acting analogues (aspart and lispro) dissociated into monomers and dimers due to the lack of zinc in the mobile phase. This comprehensive study is the first time all nine insulins have been characterised in this way, the first time that insulin detemir have been studied using analytical ultracentrifugation and the first time that insulins aspart and glulisine have been studied using sedimentation equilibrium. The structure and function of these clinically administered insulins is of critical importance and this research adds novel data to an otherwise complex functional physiological protein.

  14. Surface exposure dating of non-terrestrial bodies using optically stimulated luminescence: A new method

    DEFF Research Database (Denmark)

    Sohbati, Reza; Jain, Mayank; Murray, Andrew

    2012-01-01

    We propose a new method for in situ surface exposure dating of non-terrestrial geomorphological features using optically stimulated luminescence (OSL); our approach is based on the progressive emptying of trapped charge with exposure to light at depth into a mineral surface. A complete model...... will be applicable over the last 100 ka. The method is ideally suited to in situ measurement using existing technology developed for space applications, and so offers for the first time the realistic possibility of direct determination of exposure ages of young non-terrestrial surfaces. © 2012 Elsevier Inc. All...... rights reserved....

  15. Microplastics in the terrestrial ecosystem: Implications for Lumbricus terrestris (Oligochaeta, Lumbricidae)

    NARCIS (Netherlands)

    Huerta Lwanga, Esperanza; Gertsen, H.F.; Gooren, H.; Peters, P.D.; Salanki, T.E.; Ploeg, van der M.J.C.; Besseling, E.; Koelmans, A.A.; Geissen, V.

    2016-01-01

    Plastic debris is widespread in the environment, but information on the effects of microplastics on terrestrial fauna is completely lacking. Here, we studied the survival and fitness of the earthworm Lumbricus terrestris (Oligochaeta, Lumbricidae) exposed to microplastics (Polyethylene, <150 μm)

  16. The white space opportunity in Southern Africa: measurements with Meraka cognitive radio platform

    CSIR Research Space (South Africa)

    Masonta, MT

    2011-11-01

    Full Text Available The global migration of television (TV) from analogue to digital broadcasting will result in more spectrum bands (known as TV white space), previously used in analogue broadcasting, becoming available and unoccupied. A question is on how much white...

  17. Predictability of the terrestrial carbon cycle.

    Science.gov (United States)

    Luo, Yiqi; Keenan, Trevor F; Smith, Matthew

    2015-05-01

    Terrestrial ecosystems sequester roughly 30% of anthropogenic carbon emission. However this estimate has not been directly deduced from studies of terrestrial ecosystems themselves, but inferred from atmospheric and oceanic data. This raises a question: to what extent is the terrestrial carbon cycle intrinsically predictable? In this paper, we investigated fundamental properties of the terrestrial carbon cycle, examined its intrinsic predictability, and proposed a suite of future research directions to improve empirical understanding and model predictive ability. Specifically, we isolated endogenous internal processes of the terrestrial carbon cycle from exogenous forcing variables. The internal processes share five fundamental properties (i.e., compartmentalization, carbon input through photosynthesis, partitioning among pools, donor pool-dominant transfers, and the first-order decay) among all types of ecosystems on the Earth. The five properties together result in an emergent constraint on predictability of various carbon cycle components in response to five classes of exogenous forcing. Future observational and experimental research should be focused on those less predictive components while modeling research needs to improve model predictive ability for those highly predictive components. We argue that an understanding of predictability should provide guidance on future observational, experimental and modeling research. © 2014 John Wiley & Sons Ltd.

  18. Numerical simulations for terrestrial planets formation

    Directory of Open Access Journals (Sweden)

    Ji J.

    2011-07-01

    Full Text Available We investigate the formation of terrestrial planets in the late stage of planetary formation using two-planet model. At that time, the protostar has formed for about 3 Myr and the gas disk has dissipated. In the model, the perturbations from Jupiter and Saturn are considered. We also consider variations of the mass of outer planet, and the initial eccentricities and inclinations of embryos and planetesimals. Our results show that, terrestrial planets are formed in 50 Myr, and the accretion rate is about 60%–80%. In each simulation, 3–4 terrestrial planets are formed inside “Jupiter” with masses of 0.15–3.6 M⊕. In the 0.5–4 AU, when the eccentricities of planetesimals are excited, planetesimals are able to accrete material from wide radial direction. The plenty of water material of the terrestrial planet in the Habitable Zone may be transferred from the farther places by this mechanism. Accretion may also happen a few times between two giant planets only if the outer planet has a moderate mass and the small terrestrial planet could survive at some resonances over time scale of 108 yr.

  19. Space Weather Research: Indian perspective

    Science.gov (United States)

    Bhardwaj, Anil; Pant, Tarun Kumar; Choudhary, R. K.; Nandy, Dibyendu; Manoharan, P. K.

    2016-12-01

    Space weather, just like its meteorological counterpart, is of extreme importance when it comes to its impact on terrestrial near- and far-space environments. In recent years, space weather research has acquired an important place as a thrust area of research having implications both in space science and technology. The presence of satellites and other technological systems from different nations in near-Earth space necessitates that one must have a comprehensive understanding not only of the origin and evolution of space weather processes but also of their impact on technology and terrestrial upper atmosphere. To address this aspect, nations across the globe including India have been investing in research concerning Sun, solar processes and their evolution from solar interior into the interplanetary space, and their impact on Earth's magnetosphere-ionosphere-thermosphere system. In India, over the years, a substantial amount of work has been done in each of these areas by various agencies/institutions. In fact, India has been, and continues to be, at the forefront of space research and has ambitious future programs concerning these areas encompassing space weather. This review aims at providing a glimpse of this Indian perspective on space weather research to the reader and presenting an up-to-date status of the same.

  20. Fock representations of the superalgebra sl(n+1 vertical bar m), its quantum analogue Uq[sl(n+1 vertical bar m)] and related quantum statistics

    International Nuclear Information System (INIS)

    Palev, T.D.; Stoilova, N.I.; Jeugt, J. van der

    1999-12-01

    Fock space representations of the Lie superalgebra sl(n + 1 vertical bar m) and of its quantum analogue U q [sl(n + 1 vertical bar m)] are written down. The results are based on a description of these superalgebras via creation and annihilation operators. The properties of the underlying statistics are briefly discussed. (author)

  1. Nuclear Power in Space

    Science.gov (United States)

    1994-01-01

    In the early years of the United States space program, lightweight batteries, fuel cells, and solar modules provided electric power for space missions. As missions became more ambitious and complex, power needs increased and scientists investigated various options to meet these challenging power requirements. One of the options was nuclear energy. By the mid-1950s, research had begun in earnest on ways to use nuclear power in space. These efforts resulted in the first radioisotope thermoelectric generators (RTGs), which are nuclear power generators build specifically for space and special terrestrial uses. These RTGs convert the heat generated from the natural decay of their radioactive fuel into electricity. RTGs have powered many spacecraft used for exploring the outer planets of the solar system and orbiting the sun and Earth. They have also landed on Mars and the moon. They provide the power that enables us to see and learn about even the farthermost objects in our solar system.

  2. Spectroscopy and chemistry of interstellar ice analogues

    NARCIS (Netherlands)

    Bouwman, Jordy

    2010-01-01

    Mid-infrared (mid-IR) astronomical observations show that molecules freeze out on interstellar grains to form interstellar ices. These ices play an important role in the chemical evolution of molecules in space. Understanding the physical interactions and chemical reactions that take place in these

  3. Impact of space environment on stability of medicines: Challenges and prospects.

    Science.gov (United States)

    Mehta, Priti; Bhayani, Dhara

    2017-03-20

    To upkeep health of astronauts in a unique, isolated, and extreme environment of space is the primary goal for a successful space mission, hence, safe and efficacious medications are essential for the wellness of astronauts. Space medication has been challenged with problems related to efficacy. Along with altered physiology, one of the possible reasons could be instability of space medications in the presence of harsh spaceflight environmental conditions. Altered physical and chemical stability can result in reduced potency which can result in reduced efficacy. Right now, medicines from the International Space Station are replaced before their expiration. But, for longer duration missions to Mars or any other asteroid, there will not be any chance of replacement of medicines. Hence, it is desired that medicines maintain the shelf-life throughout the space mission. Stability of medicines used for short term or long term space missions cannot be judged by drug stability guidelines based on terrestrial environmental factors. Unique environmental conditions related to spaceflight include microgravity, excessive vibration, hard vacuum, humidity variation, temperature differences and excessive radiation, which may cause instability of medicines. This write-up provides a review of the problem and countermeasure approaches for pharmaceuticals exposed to the space environment. The first part of the article discusses thought processes behind outlining of International Conference on Harmonization drug stability guidelines, Q1A (R2) and Q1B, and its acceptance limits for accelerated stability study. The second part of the article describes the difference in the radiation environment of deep space compared to radiation environment inside the space shuttle based on penetration power of different types of radiation. In the third part of the article, various promising approaches are listed which can be used for assurance of space medicine stability. One of the approaches is the

  4. VEGETATION CHARACTERISTICS USING MULTI-RETURN TERRESTRIAL LASER SCANNER

    Directory of Open Access Journals (Sweden)

    F. Pirotti

    2012-09-01

    Full Text Available Distinguishing vegetation characteristics in a terrestrial laser scanner dataset is an interesting issue for environmental assessment. Methods for filtering vegetation points to distinguish them from ground class have been widely studied mostly on datasets derived from airborne laser scanner, less so for terrestrial laser scanners (TLS. Recent developments in terrestrial laser sensors – further ranges, faster acquisition and multiple return echoes for some models – has risen interest for surface modelling applications. The downside of TLS is that a typical dataset has a very dense cloud, with obvious side-effects on post-processing time. Here we use a scan from a sensor which provides evaluation of multiple target echoes providing with more than 70 million points on our study area. The area presents a complex set of features ranging from dense vegetation undergrowth to very steep and uneven terrain. The method consists on a first step which subsets the original points to define ground candidates by taking into account the ordinal return number and the amplitude. Next a custom progressive morphological filter (closing operation is applied on ground candidate points using multidimensional (varying resolutions grids and a structure element to determine cell values. Vegetation density mapping over the area is then estimated using a weighted ration of point counts in the tri-dimensional space over each cell. The overall result is a pipeline for processing TLS points clouds with minimal user interaction, producing a Digital Terrain Model (DTM, a Digital Surface Model (DSM a vegetation density map and a derived canopy height model (CHM. Results on DTM show an accuracy (RMSE of 0.307 m with a mean error of 0.0573 m compared to a control DTM extracted from Terrascan's progressive triangulation procedure. The derived CHM was tested over 30 tree heights resulting in 27 trees having an absolute error value below 0.2 m (three were just below 0.7 m.

  5. The Spectrum Landscape: Prospects for Terrestrial Radio Astronomy

    Science.gov (United States)

    Liszt, Harvey Steven

    2018-01-01

    Radio astronomers work within broad constraints imposed by commercial and other non-astronomical uses of the radio spectrum, somewhat modified to accommodate astronomy’s particular needs through the provision of radio quiet zones, radio frequency allocations, coordination agreements and other devices of spectrum management. As radio astronomers increase the instantaneous bandwidth, frequency coverage and sensitivity of their instruments, these external constraints, and not the limitations of their own instruments, will increasingly be the greatest obstacles to radio astronomy’s ability to observe the cosmos from the surface of the Earth. Therefore, prospects for future radio astronomy operations are contingent on situational awareness and planning for the impact of non-astronomical uses of the radio frequency spectrum. New radio astronomy instruments will have to incorporate adaptive reactions to external developments, and radio astronomers should be encouraged to think in untraditional ways. Increased attention to spectrum management is one of these. In this talk I’ll recap some recent developments such as the proliferation of 76 – 81 GHz car radar and orbiting earth-mapping radars, either of which can burn out a radio astronomy receiver. I’ll summarize present trends for non-astronomical radio spectrum use that will be coming to fruition in the next decade or so, categorized into terrestrial fixed and mobile, airborne and space-borne uses, sub-divided by waveband from the cm to the sub-mm. I’ll discuss how they will impact terrestrial radio astronomy and the various ways in which radio astronomy should be prepared to react. Protective developments must occur both within radio astronomy’s own domain – designing, siting and constructing its instruments and mitigating unavoidable RFI – and facing outward toward the community of other spectrum users. Engagement with spectrum management is no panacea but it is an important means, and perhaps the only

  6. Incorporation of tryptophan analogues into the lantibiotic nisin.

    Science.gov (United States)

    Zhou, Liang; Shao, Jinfeng; Li, Qian; van Heel, Auke J; de Vries, Marcel P; Broos, Jaap; Kuipers, Oscar P

    2016-05-01

    Lantibiotics are posttranslationally modified peptides with efficient inhibitory activity against various Gram-positive bacteria. In addition to the original modifications, incorporation of non-canonical amino acids can render new properties and functions to lantibiotics. Nisin is the most studied lantibiotic and contains no tryptophan residues. In this study, a system was constructed to incorporate tryptophan analogues into nisin, which included the modification machinery (NisBTC) and the overexpression of tryptophanyl-tRNA synthetase (TrpRS). Tryptophan and three different tryptophan analogues (5-fluoroTrp (5FW), 5-hydroxyTrp (5HW) and 5-methylTrp (5MeW)) were successfully incorporated at four different positions of nisin (I1W, I4W, M17W and V32W). The incorporation efficiency of tryptophan analogues into mutants I1W, M17W and V32W was over 97 %, while the mutant I4W showed relatively low incorporation efficiency (69-93 %). The variants with 5FW showed relatively higher production yield, while 5MeW-containing variants showed the lowest yield. The dehydration efficiency of serines or threonines was affected by the tryptophan mutants of I4W and V32W. The affinity of the peptides for the cation-ion exchange and reverse phase chromatography columns was significantly reduced when 5HW was incorporated. The antimicrobial activity of IIW and its 5FW analogue both decreased two times compared to that of nisin, while that of its 5HW analogue decreased four times. The 5FW analogue of I4W also showed two times decreased activity than nisin. However, the mutant M17W and its 5HW analogue both showed 32 times reduced activity relative to that of nisin.

  7. Insulin analogues and cancer: a note of caution

    Directory of Open Access Journals (Sweden)

    Joseph A.M.J.L. eJanssen

    2014-05-01

    Full Text Available Abstract In view of the lifelong exposure and large patient populations involved, insulin analogues with an increased mitogenic effect in comparison to human insulin may potentially constitute a major health problem, since these analogues may possibly induce the growth of pre-existing neoplasms. At present, the available data suggest that insulin analogues are safe. In line with these findings, we observed that serum of diabetic patients treated with insulin analogues, compared to that of diabetic patients treated with human insulin, did not induce an increased phosphorylation of tyrosine residues of the insulin-like growth factor-I receptor (IGF-IR. However, the classical model of the IGF-IR signaling may be insufficient to explain (all mitogenic effects of insulin analogues since also non-canonical signaling pathways of the IGF-IR may play a major role in this respect. Although phosphorylation of tyrosine residues of the IGF-IR is generally considered to be the initial activation step within the intracellular IGF-IR signaling pathway, it has been found that cells undergo a signaling switch under hyperglycemic conditions. After this switch, a completely different mechanism is utilized to activate the mitogenic (mitogen-activated protein kinase (MAPK pathways of the IGF-IR that is independent from tyrosine phosphorylation of the IGF-IR. At present it is unknown whether activation of this alternative intracellular pathway of the IGF-IR occurs during hyperglycemia in vivo and whether it is stronger in patients treated with (some insulin analogues than in patients treated with human insulin. In addition, it is unknown whether the insulin receptors (IRs also undergo a signaling switch during hyperglycemia. This should be investigated in future studies. Finally, relative overexpression of IR isoform A (IR-A in (pre cancer tissues may play a key role in the development and progression of human cancers during treatment with insulin (analogues. Further

  8. Response of Staphylococcus Aureus to a Spaceflight Analogue

    Science.gov (United States)

    Castro, S. L.; Ott, C. M.

    2010-01-01

    The decreased gravity of the spaceflight environment creates quiescent, low fluid shear conditions. This environment can impart considerable effects on the physiology of microorganisms as well as their interactions with potential hosts. Using the rotating wall vessel (RWV), as a spaceflight analogue, the consequence of low fluid shear culture on microbial pathogenesis has provided a better understanding of the risks to the astronaut crew from infectious microorganisms. While the outcome of low fluid shear culture has been investigated for several bacterial pathogens, little has been done to understand how this environmental factor affects Staphylococcus aureus. S. aureus is an opportunistic human pathogen which presents a high level of infection risk to the crew, as it has been isolated from both the space shuttle and International Space Station. Given that approximately forty percent of the population are carriers of the bacteria, eradication of this organism from in flight environments is impractical. These reasons have lead to us to assess the response of S. aureus to a reduced fluid shear environment. Culture in the RWV demonstrated that S. aureus grown under the low-shear condition had lower cell concentrations after 10 hours when compared to the control culture. Furthermore, the low-shear cultured bacteria displayed a reduction in carotenoid production, pigments responsible for their yellow/gold coloration. When exposed to various environmental stressors, post low-shear culture, a decrease in the ability to survive oxidative assault was observed compared to control cultures. The low fluid shear environment also resulted in a decrease in hemolysin secretion, a staphylococcal toxin responsible for red blood cell lysis. When challenged by the immune components present in human whole blood, low-shear cultured S. aureus demonstrated significantly reduced survival rates as compared to the control culture. Assays to determine the duration of these alterations

  9. A molecular palaeobiological exploration of arthropod terrestrialization

    DEFF Research Database (Denmark)

    Lozano-Fernandez, Jesus; Carton, Robert; Tanner, Alastair R.

    2016-01-01

    to the colonization of land is the most likely scenario.Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record,Myriapoda are inferred to have colonized land...... earlier, substantially predating trace or body fossil evidence. An estimated origin of myriapods by the Early Cambrian precedes the appearance of embryophytes and perhaps even terrestrial fungi, raising the possibility that terrestrialization had independent origins in crown-group myriapod lineages......, consistent with morphological arguments for convergence in tracheal systems. This article is part of the themed issue ‘Dating species divergences using rocks and clocks’....

  10. Results of the first Seismometer to Investigate Ice and Ocean Structure (SIIOS) Analogue Mission

    Science.gov (United States)

    Della-Giustina, Daniella; Bray, Veronica; "Hop" Bailey, Samuel; Pettit, Erin; Schmerr, Nicholas; Dahl, Peter; Avenson, Brad; Byrne, Shane; SIIOS Team

    2017-10-01

    The icy moons of Europa and Enceladus are thought to have global subsurface oceans in contact with mineral-rich interiors, likely providing the ingredients needed for life as we know it. The possibility of life forming in the ocean or in melt pockets, relies on the presence of a source of energy and chemistry for biological molecule formation. A thick, stagnant ice crust would likely prevent transfer of oxidants from the surface to the water, halting the development of life. The ice thickness and structure is therefore one of the most important and controversial topics in astrobiology.The best way to access an icy moon’s interior structure is with a lander-based seismometer. Our team has identified a commercial-off-the-shelf device as a flight-candidate for operation in the extreme environment of the icy moons. Based on estimates of Europan seismicity, the flight candidate device is sensitive enough to detect the ice-water boundary and pockets of liquid within the ice. Its low mass and low power enables deployment of multiple seismometers in a short-baseline array on a lander. The performance, mass, and volume of this device meet or exceed flight requirements identified in lander studies making a field test of these seismometers highly representative of a flight unit developed for an Ocean Worlds mission.We report the results of the first field campaign for the SIIOS Analogue Mission Program (AMP), which has evaluates the performance of the flight candidate seismometer in Ocean World terrestrial analogue environments. In particular, the first SIIOS AMP field exercise is performed at Gulkana Glacier, Alaska. During the summer melt season Gulkana provides kilometer-scale regions of coexisting ice, water, and silicate material, thereby providing areas with the desired analogue seismic contrasts. During this first mission, we have demonstrated device sensitivity to the detection of seismicity from high frequency (> 50 Hz) active and passive sources, the depth of ice

  11. MARKOV GRAPHS OF ONE–DIMENSIONAL DYNAMICAL SYSTEMS AND THEIR DISCRETE ANALOGUES AND THEIR DISCRETE ANALOGUES

    Directory of Open Access Journals (Sweden)

    SERGIY KOZERENKO

    2016-04-01

    Full Text Available One feature of the famous Sharkovsky’s theorem is that it can be proved using digraphs of a special type (the so–called Markov graphs. The most general definition assigns a Markov graph to every continuous map from the topological graph to itself. We show that this definition is too broad, i.e. every finite digraph can be viewed as a Markov graph of some one–dimensional dynamical system on a tree. We therefore consider discrete analogues of Markov graphs for vertex maps on combinatorial trees and characterize all maps on trees whose discrete Markov graphs are of the following types: complete, complete bipartite, the disjoint union of cycles, with every arc being a loop.

  12. Causality and Borromean linking in twistor space

    Energy Technology Data Exchange (ETDEWEB)

    Low, Robert J, E-mail: mtx014@coventry.ac.uk [Department of Mathematics, Statistics and Engineering Science, Coventry University, Coventry CV1 5FB (United Kingdom)

    2011-10-01

    We consider the notion of the Borromean triple from classical linking theory, and develop an analogue of it in the case of linking of skies in twistor space. I would like to dedicate this paper to Roger Penrose, on the occasion of his 80th birthday.

  13. Oligo-Miocene peatland ecosystems of the Gippsland Basin and modern analogues

    Science.gov (United States)

    Korasidis, Vera A.; Wallace, Malcolm W.; Wagstaff, Barbara E.; Holdgate, Guy R.

    2017-02-01

    A detailed examination of the brown coal facies preserved in the Latrobe Valley Morwell 1B seam indicates that the type of peat-forming environment and the associated hydrological regime are the main factors influencing the development of lithotypes in brown coal deposits. New palynological data from the Morwell 1B seam suggests that each respective lithotype in the lightening-upwards lithotype cycles was deposited in a particular depositional environment that was characterised by a distinct floral community. The laminated dark lithotype represents a fire-prone emergent marsh that grew on the margins of a coastal lagoon and/or freshwater swamp. This facies grades into the dark lithotype, representing the transition from a meadow marsh to a periodically flooded ombrogenous forested bog. The medium and lighter lithotypes are interpreted as being deposited in an angiosperm-dominated ombrogenous forest bog that was intolerant of fire. These peat-forming environments are interpreted as being largely controlled by moisture and relative depth to water table. Each environment produces distinct lithotypes and lightening-upwards cycles are interpreted as terrestrialization cycles. As the peat grew upwards and above the water table, less moist conditions prevailed and lighter lithotypes were produced. The observed change in colour, from darker to lighter lithotypes, results from the environment evolving from anaerobic/inundated to less anaerobic/less moist settings via terrestrialization. The thin and laterally extensive light and pale lithotypes that top the cycles are interpreted to represent a residual layer of concentrated, oxidation resistant peat-forming elements that result from intense weathering and aerobic degradation of the peats. At a generic level, modern lowland bogs of South Westland in New Zealand have remarkably similar floral/ecological gradients to those of the Oligo-Miocene Morwell 1B brown coal cycles in Australia. This suggests that modern New Zealand

  14. Terrestrial propagation of long electromagnetic waves

    CERN Document Server

    Galejs, Janis; Fock, V A

    2013-01-01

    Terrestrial Propagation of Long Electromagnetic Waves deals with the propagation of long electromagnetic waves confined principally to the shell between the earth and the ionosphere, known as the terrestrial waveguide. The discussion is limited to steady-state solutions in a waveguide that is uniform in the direction of propagation. Wave propagation is characterized almost exclusively by mode theory. The mathematics are developed only for sources at the ground surface or within the waveguide, including artificial sources as well as lightning discharges. This volume is comprised of nine chapte

  15. Evolutionary tracks of the terrestrial planets

    International Nuclear Information System (INIS)

    Matsui, Takafumi; Abe, Yutaka

    1987-01-01

    On the basis of the model proposed by Matsui and Abe, the authors show that two major factors - distance from the Sun and the efficiency of retention of accretional energy - control the early evolution of the terrestrial planets. A diagram of accretional energy versus the optical depth of a proto-atmosphere provides a means to follow the evolutionary track of surface temperature of the terrestrial planets and an explanation for why the third planet in our solar system is an 'aqua'-planet. 15 refs; 3 figs

  16. Strong coupling analogue of the Born series

    International Nuclear Information System (INIS)

    Dolinszky, T.

    1989-10-01

    In a given partial wave, the strength of the centrifugal term to be incorporated into the WKBA solutions in different spatial regions can be adjusted so as to make the first order wave functions everywhere smooth and, in strong coupling, exactly reproduce Quantum Mechanics throughout the space. The relevant higher order approximations supply an absolute convergent series expansion of the exact scattering state. (author) 4 refs.; 2 figs.; 2 tabs

  17. Effects of Terrestrial Buffer Zones on Amphibians on Golf Courses

    Science.gov (United States)

    Puglis, Holly J.; Boone, Michelle D.

    2012-01-01

    A major cause of amphibian declines worldwide is habitat destruction or alteration. Public green spaces, such as golf courses and parks, could serve as safe havens to curb the effects of habitat loss if managed in ways to bolster local amphibian communities. We reared larval Blanchard's cricket frogs (Acris blanchardi) and green frogs (Rana clamitans) in golf course ponds with and without 1 m terrestrial buffer zones, and released marked cricket frog metamorphs at the golf course ponds they were reared in. Larval survival of both species was affected by the presence of a buffer zone, with increased survival for cricket frogs and decreased survival for green frogs when reared in ponds with buffer zones. No marked cricket frog juveniles were recovered at any golf course pond in the following year, suggesting that most animals died or migrated. In a separate study, we released cricket frogs in a terrestrial pen and allowed them to choose between mown and unmown grass. Cricket frogs had a greater probability of using unmown versus mown grass. Our results suggest that incorporating buffer zones around ponds can offer suitable habitat for some amphibian species and can improve the quality of the aquatic environment for some sensitive local amphibians. PMID:22761833

  18. Unique Spectroscopy and Imaging of Terrestrial Planets with JWST

    Science.gov (United States)

    Villanueva, Geronimo Luis; JWST Mars Team

    2017-06-01

    In this talk, I will present the main capabilities of the James Webb Space Telescope (JWST) for performing observations of terrestrial planets, using Mars as a test case. The distinctive vantage point of JWST at the Sun-Earth Lagrange point (L2) will allow sampling the full observable disk, permitting the study of short-term phenomena, diurnal processes (across the East-West axis) and latitudinal processes between the hemispheres (including seasonal effects) with excellent spatial resolutions (0.07 arcsec at 2 um). Spectroscopic observations will be achievable in the 0.7-5 um spectral region with NIRSpec at a maximum resolving power of 2700, and with 8000 in the 1-1.25 um range. Imaging will be attainable with NIRCam at 4.3 um and with two narrow filters near 2 um, while the nightside will be accessible with several filters in the 0.5 to 2 um. Such a powerful suite of instruments will be a major asset for the exploration and characterization of Mars, and terrestrial planets in general. Some science cases include the mapping of the water D/H ratio, investigations of the Martian mesosphere via the characterization of the non-LTE CO2 emission at 4.3 um, studies of chemical transport via observations of the O2 nightglow at 1.27 um, high cadence mapping of the variability dust and water ice clouds, and sensitive searches for trace species and hydrated features on the planetary surface.

  19. Theoretical study on absorption and emission spectra of adenine analogues.

    Science.gov (United States)

    Liu, Hongxia; Song, Qixia; Yang, Yan; Li, Yan; Wang, Haijun

    2014-04-01

    Fluorescent nucleoside analogues have attracted much attention in studying the structure and dynamics of nucleic acids in recent years. In the present work, we use theoretical calculations to investigate the structural and optical properties of four adenine analogues (termed as A1, A2, A3, and A4), and also consider the effects of aqueous solution and base pairing. The results show that the fluorescent adenine analogues can pair with thymine to form stable H-bonded WC base pairs. The excited geometries of both adenine analogues and WC base pairs are similar to the ground geometries. The absorption and emission maxima of adenine analogues are greatly red shifted compared with nature adenine, the oscillator strengths of A1 and A2 are stronger than A3 and A4 in both absorption and emission spectra. The calculated low-energy peaks in the absorption spectra are in good agreement with the experimental data. In general, the aqueous solution and base pairing can slightly red-shift both the absorption and emission maxima, and can increase the oscillator strengths of absorption spectra, but significantly decrease the oscillator strengths of A3 in emission spectra.

  20. A preliminary feasibility study on natural analogue in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Koh, Yong Kwon; Park, Byung Yun

    2000-03-01

    Preliminary study on the assessment of natural analogue study in Korea for the deep geological disposal of high-level radioactive waste was carried out. The project on natural analogue study in other countries are introduced. The uranium-bearing deposit in Okcheon belt are summarized, which reported to be uranium-bearing minerals in order to assess to feasibility for natural analogue study in Korea. Among the uranium-bearing deposits, the Deokpyeong area, reported to be the highest reservoir and grade, are selected as the study site, and the elementary investigation, including survey of radioactivity and geochemistry are carried out. According to the investigation of surface environment, the radioactivity and uranium content in the surface water and shallow groundwater does not show any anormal values. However, the radioactivity is expected to be increased in depth and the groundwater reacted with uranium-bearing graphite formation shows high unanium content, indicating the potential possibility for natural analogue study in Korea. In future, if more detail study are performed, the assessment of natural analogue study in Korea are expected.

  1. Adjuvants Based on Synthetic Mycobacterial Cord Factor Analogues: Biophysical Properties of Neat Glycolipids and Nanoself-Assemblies with DDA.

    Science.gov (United States)

    Kallerup, Rie S; Franzyk, Henrik; Schiøth, Mikkel L; Justesen, Sarah; Martin-Bertelsen, Birte; Rose, Fabrice; Madsen, Cecilie M; Christensen, Dennis; Korsholm, Karen S; Yaghmur, Anan; Foged, Camilla

    2017-07-03

    Synthetic mycobacterial cord factor analogues, e.g., trehalose 6,6'-dibehenate (TDB), are highly promising adjuvants due to their strong immunopotentiating capabilities, but their biophysical properties have remained poorly characterized. Here, we report the synthesis of an array of synthetic TDB analogues varying in acyl chain length, degree of acylation, and headgroup display, which was subjected to biophysical characterization of neat nondispersed self-assembled nanostructures in excess buffer and as aqueous dispersions with cationic dimethyldioctadecylammonium (DDA) bromide. The array comprised trehalose mono- (TMX) and diester (TDX) analogues with symmetrically shortened acyl chains [denoted by X: arachidate (A), stearate (S), palmitate (P), myristate (Myr), and laurate (L)] and an analogue with a short hydrophilic polyethylene glycol (PEG) linker inserted between the trehalose headgroup of TDS and the acyl chains (PEG-TDS). All dispersions were liposomes, but in contrast to the colloidally stable and highly cationic TDX-containing liposomes, the zeta-potential was significantly reduced for DDA/TMX and DDA/PEG-TDS liposomes, suggesting a charge-shielding effect, which compromises the colloidal stability. An increased d-spacing was observed for the lamellar phase of neat TDB analogues in excess buffer (TDS < TMS < PEG-TDS), confirming that the charge shielding is caused by an extended molecular configuration of the more flexible headgroup. Differential scanning calorimetry showed highly cooperative phase transitions for all tested dispersions albeit the monoesters destabilized the lipid bilayers. Langmuir experiments demonstrated that incorporation of TDXs and PEG-TDS stabilized DDA monolayers due to improved hydrogen bonding and reduced intermolecular repulsions. In conclusion, data suggest that the DDA/TDS dispersions exhibit favorable physicochemical properties rendering these DDA/TDS liposomes an attractive vaccine adjuvant, and they emphasize that not only

  2. Microplastics in the Terrestrial Ecosystem: Implications for Lumbricus terrestris (Oligochaeta, Lumbricidae).

    Science.gov (United States)

    Huerta Lwanga, Esperanza; Gertsen, Hennie; Gooren, Harm; Peters, Piet; Salánki, Tamás; van der Ploeg, Martine; Besseling, Ellen; Koelmans, Albert A; Geissen, Violette

    2016-03-01

    Plastic debris is widespread in the environment, but information on the effects of microplastics on terrestrial fauna is completely lacking. Here, we studied the survival and fitness of the earthworm Lumbricus terrestris (Oligochaeta, Lumbricidae) exposed to microplastics (Polyethylene, digestion of ingested organic matter, microplastic was concentrated in cast, especially at the lowest dose (i.e., 7% in litter) because that dose had the highest proportion of digestible organic matter. Whereas 50 percent of the microplastics had a size of earthworms. These concentration-transport and size-selection mechanisms may have important implications for fate and risk of microplastic in terrestrial ecosystems.

  3. Terrestrial water fluxes dominated by transpiration: Comment

    Science.gov (United States)

    Daniel R. Schlaepfer; Brent E. Ewers; Bryan N. Shuman; David G. Williams; John M. Frank; William J. Massman; William K. Lauenroth

    2014-01-01

    The fraction of evapotranspiration (ET) attributed to plant transpiration (T) is an important source of uncertainty in terrestrial water fluxes and land surface modeling (Lawrence et al. 2007, Miralles et al. 2011). Jasechko et al. (2013) used stable oxygen and hydrogen isotope ratios from 73 large lakes to investigate the relative roles of evaporation (E) and T in ET...

  4. South African red data book - Terrestrial mammals

    CSIR Research Space (South Africa)

    Smithers, RHN

    1986-01-01

    Full Text Available Currently, 243 species of terrestrial wild mammals are known to occur in the Republic of South Africa. Using the well established IUCN definitions, 42 of these may be considered as exposed to some level of threat of extinction. Three species...

  5. Strategies for monitoring terrestrial animals and habitats

    Science.gov (United States)

    Richard Holthausen; Raymond L. Czaplewski; Don DeLorenzo; Greg Hayward; Winifred B. Kessler; Pat Manley; Kevin S. McKelvey; Douglas S. Powell; Leonard F. Ruggiero; Michael K. Schwartz; Bea Van Horne; Christina D. Vojta

    2005-01-01

    This General Technical Report (GTR) addresses monitoring strategies for terrestrial animals and habitats. It focuses on monitoring associated with National Forest Management Act planning and is intended to apply primarily to monitoring efforts that are broader than individual National Forests. Primary topics covered in the GTR are monitoring requirements; ongoing...

  6. High efficiency, long life terrestrial solar panel

    Science.gov (United States)

    Chao, T.; Khemthong, S.; Ling, R.; Olah, S.

    1977-01-01

    The design of a high efficiency, long life terrestrial module was completed. It utilized 256 rectangular, high efficiency solar cells to achieve high packing density and electrical output. Tooling for the fabrication of solar cells was in house and evaluation of the cell performance was begun. Based on the power output analysis, the goal of a 13% efficiency module was achievable.

  7. Cepstrum Analysis of Terrestrial Impact Crater Records

    Directory of Open Access Journals (Sweden)

    Heon-Young Chang

    2008-06-01

    Full Text Available Study of terrestrial impact craters is important not only in the field of the solar system formation and evolution but also of the Galactic astronomy. The terrestrial impact cratering record recently has been examined, providing short- and intermediate-term periodicities, such as, Myrs, Myrs. The existence of such a periodicity has an implication in the Galactic dynamics, since the terrestrial impact cratering is usually interpreted as a result of the environmental variation during solar orbiting in the Galactic plane. The aim of this paper is to search for a long-term periodicity with a novel method since no attempt has been made so far in searching a long-term periodicity in this research field in spite of its great importance. We apply the cepstrum analysis method to the terrestrial impact cratering record for the first time. As a result of the analysis we have found noticeable peaks in the Fourier power spectrum appear ing at periods of Myrs and Myrs, which seem in a simple resonance with the revolution period of the Sun around the Galactic center. Finally we briefly discuss its implications and suggest theoretical study be pursued to explain such a long-term periodicity.

  8. Furostanol and Spirostanol Saponins from Tribulus terrestris.

    Science.gov (United States)

    Wang, Zhen-Fang; Wang, Bing-Bing; Zhao, Yang; Wang, Fang-Xu; Sun, Yan; Guo, Rui-Jie; Song, Xin-Bo; Xin, Hai-Li; Sun, Xin-Guang

    2016-03-30

    Twelve new steroidal saponins, including eleven furostanol saponins, terrestrinin J-T (1-11), and one spirostanol saponin, terrestrinin U (12), together with seven known steroidal saponins 13-19 were isolated from T. terrestris. The structures of the new compounds were established on the basis of spectroscopic data, including 1D and 2D NMR and HRESIMS, and comparisons with published data.

  9. Ethnopharmacological Studies of Tribulus Terrestris (Linn). in ...

    African Journals Online (AJOL)

    Synergism and antagonism impact of different plant metabolites present in crude fruit extract of Tribulus terrestris 'the herbal Viagra' have been studied. Variability in plant composition, biomass and metabolites concentration in different modules was significantly contributed by spatial factor. However the edhaphic ...

  10. CarbAl(TM) Based Thermal Management for Space Flight Systems Application Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Thermal Transfer is a critical part of power electronics application in both terrestrial and space environments. Due to longer lifetime expectancies and harsh...

  11. Benefits and Pitfalls of GRACE Terrestrial Water Storage Data Assimilation

    Science.gov (United States)

    Girotto, Manuela

    2018-01-01

    Satellite observations of terrestrial water storage (TWS) from the Gravity Recovery and Climate Experiment (GRACE) mission have a coarse resolution in time (monthly) and space (roughly 150,000 sq km at midlatitudes) and vertically integrate all water storage components over land, including soil moisture and groundwater. Nonetheless, data assimilation can be used to horizontally downscale and vertically partition GRACE-TWS observations. This presentation illustrates some of the benefits and drawbacks of assimilating TWS observations from GRACE into a land surface model over the continental United States and India. The assimilation scheme yields improved skill metrics for groundwater compared to the no-assimilation simulations. A smaller impact is seen for surface and root-zone soil moisture. Further, GRACE observes TWS depletion associated with anthropogenic groundwater extraction. Results from the assimilation emphasize the importance of representing anthropogenic processes in land surface modeling and data assimilation systems.

  12. Applications of plasma core reactors to terrestrial energy systems

    Science.gov (United States)

    Latham, T. S.; Biancardi, F. R.; Rodgers, R. J.

    1974-01-01

    Plasma core reactors offer several new options for future energy needs in addition to space power and propulsion applications. Power extraction from plasma core reactors with gaseous nuclear fuel allows operation at temperatures higher than conventional reactors. Highly efficient thermodynamic cycles and applications employing direct coupling of radiant energy are possible. Conceptual configurations of plasma core reactors for terrestrial applications are described. Closed-cycle gas turbines, MHD systems, photo- and thermo-chemical hydrogen production processes, and laser systems using plasma core reactors as prime energy sources are considered. Cycle efficiencies in the range of 50 to 65 percent are calculated for closed-cycle gas turbine and MHD electrical generators. Reactor advantages include continuous fuel reprocessing which limits inventory of radioactive by-products and thorium-U-233 breeder configurations with about 5-year doubling times.-

  13. DW complexes and their underlying topological spaces | Ntumba ...

    African Journals Online (AJOL)

    The naïve concept of a DW complex is that of a differential space that can be built up from cells and whose differential structure is defined in terms of differential structures on Euclidean unit closed balls. This concept stems from an analogue in the category of topological spaces: the so-called CW complex. The paper goes as ...

  14. Charged fluid distribution in higher dimensional spheroidal space-time

    Indian Academy of Sciences (India)

    analogue of Tolman's solutions. Recently, Ponce de Leon and Cruz [11] have con- sidered higher dimensional Schwarzschild space-time and studied the influence of the extra dimensions on the equilibrium configuration of stars. Vaidya and Tikekar. [12] have discussed spheroidal space-time and obtained an exact model ...

  15. Concise synthesis of new bridged-nicotine analogues

    DEFF Research Database (Denmark)

    Crestey, François; Hooyberghs, Geert; Kristensen, Jesper Langgaard

    2012-01-01

    This study describes a very efficient strategy for the synthesis of two new bridged-nicotine analogues. Starting from either 4- or 3-chloropyridine the desired tricyclic ring systems are accessed in just three steps in 23% and 40% overall yield, respectively.......This study describes a very efficient strategy for the synthesis of two new bridged-nicotine analogues. Starting from either 4- or 3-chloropyridine the desired tricyclic ring systems are accessed in just three steps in 23% and 40% overall yield, respectively....

  16. Desert spring mounds: a potential analogue to Martian arid environments?

    Science.gov (United States)

    Franchi, F.; Frisia, S.

    2017-09-01

    Spring carbonates have been often considered as putative analogues of Martian arid environments. On Earth these are believed to form by the interaction of highly saline water and microbial communities, which favor the formation of authigenic micrite. Here we present new data from spring mounds in the western Makgadikgadi Pan (Botswana) and the Great Artesian Basin (South Australia). In both areas, upwelling of ground water give rise to mounds and layered deposits which are close morphological analogues of landforms documented on Mars. The authigenic carbonates and evaporites associated with the spring mounds retain evidence of microbial microfabric founded elsewhere, pointing to the potential existence of similar microbial in the extreme Martian conditions.

  17. Medical applications of analogue and digital telephone data links.

    Science.gov (United States)

    Hill, D W; Mable, S E; Payne, J P

    1976-07-20

    The increasing use of digital computer techniques for the analysis of signals such as the EEG, ECG, plethysmograms and cardiac output curves has led to the use of multichannel analogue frequency modulation telephone data links in the forward direction from the patient to the computer and digital links in the return direction. Single-channel analogue links are also being used for the surveillance of cardiac pacemaker patients and the television Viewphone offers the possibility of a visual contact between two centers. Examples will be given of the use of these various forms of telephone link.

  18. Naturally occurring crystalline phases: analogues for radioactive waste forms

    International Nuclear Information System (INIS)

    Haaker, R.F.; Ewing, R.C.

    1981-01-01

    Naturally occurring mineral analogues to crystalline phases that are constituents of crystalline radioactive waste forms provide a basis for comparison by which the long-term stability of these phases may be estimated. The crystal structures and the crystal chemistry of the following natural analogues are presented: baddeleyite, hematite, nepheline; pollucite, scheelite;sodalite, spinel, apatite, monazite, uraninite, hollandite-priderite, perovskite, and zirconolite. For each phase in geochemistry, occurrence, alteration and radiation effects are described. A selected bibliography for each phase is included

  19. Naturally occurring crystalline phases: analogues for radioactive waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Haaker, R.F.; Ewing, R.C.

    1981-01-01

    Naturally occurring mineral analogues to crystalline phases that are constituents of crystalline radioactive waste forms provide a basis for comparison by which the long-term stability of these phases may be estimated. The crystal structures and the crystal chemistry of the following natural analogues are presented: baddeleyite, hematite, nepheline; pollucite, scheelite;sodalite, spinel, apatite, monazite, uraninite, hollandite-priderite, perovskite, and zirconolite. For each phase in geochemistry, occurrence, alteration and radiation effects are described. A selected bibliography for each phase is included.

  20. A Low-cost Multi-channel Analogue Signal Generator

    CERN Document Server

    Müller, F; The ATLAS collaboration; Shen, W; Stamen, R

    2009-01-01

    A scalable multi-channel analogue signal generator is presented. It uses a commercial low-cost graphics card with multiple outputs in a standard PC as signal source. Each color signal serves as independent channel to generate an analogue signal. A custom-built external PCB was developed to adjust the graphics card output voltage levels for a specific task, which needed differential signals. The system furthermore comprises a software package to program the signal shape. The implementation of the signal generator is presented as well as an application where it was successfully utilized.

  1. Neurochemical binding profiles of novel indole and benzofuran MDMA analogues.

    OpenAIRE

    Shimshoni, JA; Winkler, I; Golan, E; Nutt, D

    2016-01-01

    3,4-Methylenedioxy-N-methylamphetamine (MDMA) has been shown to be effective in the treatment of post-traumatic stress disorder (PTSD) in numerous clinical trials. In the present study, we have characterized the neurochemical binding profiles of three MDMA-benzofuran analogues (1-(benzofuran-5-yl)-propan-2-amine, 5-APB; 1-(benzofuran-6-yl)-N-methylpropan-2-amine, 6-MAPB; 1-(benzofuran-5-yl)-N-methylpropan-2-amine, 5-MAPB) and one MDMA-indole analogue (1-(1H-indol-5-yl)-2-methylamino-propan-1-...

  2. Natural analogues, paradigm for manmade repositories for radioactive wastes

    International Nuclear Information System (INIS)

    Pavelescu, M.; Pavelescu, A.

    2004-01-01

    Natural analogues are given by nature. They show the results of natural processes which have lasted thousands or millions of years. They provide an excellent example of what could happen in an underground site, offering in the same time the opportunity to test by observation and measurement, many of the geochemical processes that are expected to influence in a realistic and appropriate way, the predicted reliability of the radioactive waste repository over long periods of geological time. The natural analogue studies attempt to understand the multiprocessing complexity of the natural system, which contrasts with the limitations of the laboratory experiments and bring arguments to overcome the difficult time scale issue. By this the natural analogues are a useful paradigm for manmade repository for radioactive wastes. The paper discusses the implicit link in the public mind between natural analogues and manmade waste repository with an accent of the positive impact on public acceptance. It is also discussed the decisive qualities of the natural analogues concerning providing valid long term data and increasing the confidence of the public for manmade repositories. The debate is conducting in terms of sustainable development, having at base high-level principles in order to protect humans and their environment, both now and in the future, from potential hazards arising from such wastes. Safe radwaste management involves the application of technology and resources in a regulated manner so that the public, workers and the environment are protected in accordance with the accepted national and international standards. There are at least seven high-level principles which are mentioned in the paper. It is presented the general concept of the deep geological repository, very important for an acceptable solution for the management of nuclear waste, what is a prerequisite for a renewal of nuclear power. Further are introduced natural and archaeological (manufactured) analogue

  3. Adjuvants based on synthetic mycobacterial cord factor analogues: Biophysical properties of neat glycolipids and nano-self-assemblies with DDA

    DEFF Research Database (Denmark)

    Kallerup, Rie Selchau; Franzyk, Henrik; Schiøth, Mikkel Lohmann

    2017-01-01

    Synthetic mycobacterial cord factor analogues, e.g., trehalose 6,6'-dibehenate (TDB), are highly promising adjuvants due to their strong immunopotentiating capabilities, but their biophysical properties have remained poorly characterized. Here, we report the synthesis of an array of synthetic TDB...... and the acyl chains (PEG-TDS). All dispersions were liposomes, but in contrast to the colloidally stable and highly cationic TDX-containing liposomes, the zeta-potential was significantly reduced for DDA/TMX and DDA/PEG-TDS liposomes, suggesting a charge-shielding effect, which compromises the colloidal...... stability. An increased d-spacing was observed for the lamellar phase of neat TDB analogues in excess buffer (TDShighly cooperative...

  4. Engineering, construction, and operations in space - III: Space '92; Proceedings of the 3rd International Conference, Denver, CO, May 31-June 4, 1992. Vols. 1 & 2

    Science.gov (United States)

    Sadeh, Willy Z.; Sture, Stein; Miller, Russell J.

    The present volume on engineering, construction, and operations in space discusses surface structures on the moon and Mars, surface equipment, construction, and transportation on the moon and Mars, in situ materials use and processing, and space energy. Attention is given to such orbital structures as LEO and the space station, space mining and excavation, space materials, space automation and robotics, and space life support systems. Topics addressed include lunar-based astronomy, space systems integration, terrestrial support for space functions, and space education. Also discussed are space plans, policy, and history, space science and engineering, geoengineering and space exploration, and the construction and development of a human habitat on Mars.

  5. Louisiana ESI: T_MAMMAL (Terrestrial Mammal Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for terrestrial mammals in Louisiana. Vector polygons in this data set represent terrestrial mammal...

  6. 76 FR 50274 - Terrestrial Environmental Studies for Nuclear Power Stations

    Science.gov (United States)

    2011-08-12

    ... NUCLEAR REGULATORY COMMISSION [NRC-2011-0182] Terrestrial Environmental Studies for Nuclear Power... draft regulatory guide (DG), DG-4016, ``Terrestrial Environmental Studies for Nuclear Power Stations... environmental studies and analyses supporting licensing decisions for nuclear power reactors. DATES: Submit...

  7. Nilpotent Quantum Mechanics: Analogues and Applications

    Science.gov (United States)

    Marcer, Peter; Rowlands, Peter

    2017-07-01

    The most significant characteristic of nilpotent quantum mechanics is that the quantum system (fermion state) and its environment (vacuum) are, in mathematical terms, mirror images of each other. So a change in one automatically leads to corresponding changes in the other. We have used this characteristic as a model for self-organization, which has applications well beyond quantum physics. The nilpotent structure has also been identified as being constructed from two commutative vector spaces. This construction has a number of identifiable characteristics which we can expect to find in systems where self-organization is dominant, and a case presented after the publication of a paper by us on ‘The ‘Logic’ of Self-Organizing Systems’,1 in the organization of the neurons in the visual cortex. We expect to find many more complex systems where our general principles, based, by analogy, on nilpotent quantum mechanics, will apply.

  8. From Greenhouse to Icehouse: Marine and Terrestrial Palynological Evidence for Climatic and Oceanic Change Through the Cenozoic of the Arctic

    Science.gov (United States)

    Bujak, J. P.; Brinkhuis, H.

    2004-12-01

    The marine and terrestrial biotas of northern Alaska and the Canadian Beaufort Mackenzie Basin (BMB) are intimately linked to changes in the climate and oceanography of the region. These changes can be reconstructed using palynological data from surface sections and numerous exploration wells drilled in the region over the past 30 years. During the Late Triassic to Early Eocene, marine dinoflagellate cyst (dinocyst) and terrestrial miospore (pollen and spore) palynomorphs were diverse and abundant across the region, reflecting the presence of a relatively warm and productive polar ocean that was fringed by extensive forests. The region was heated by northward-flowing Pacific currents, but lay north of the Arctic Circle and had seasonal 24 hour winter darkness and summer daylight. No modern analogue exists for this environment. A dramatic change occurred at the end of the Early Eocene as global climate shifted from the greenhouse towards the modern icehouse world. This had a particularly strong effect in high latitudes. A succession of major extinction events reflected falling sea and air temperatures in the Arctic and progressively eliminated marine and terrestrial species from the region. These events can be correlated with Eocene cooling steps known from the North Atlantic, where they had a milder effect, and provide a chronostratigraphic link between the regions. By Oligocene time the Arctic populations were strongly impoverished, but Miocene warming permitted the immigration of cold-temperate species including marine dinoflagellates and terrestrial angiosperms. Following this warm phase, the marine and terrestrial populations became increasingly restricted as air and water temperatures fell during the Plio-Pleistocene, leading to the modern highly endemic Arctic biotas.

  9. Symplectic geometry on moduli spaces of holomorphic bundles over complex surfaces

    OpenAIRE

    Khesin, Boris; Rosly, Alexei

    2000-01-01

    We give a comparative description of the Poisson structures on the moduli spaces of flat connections on real surfaces and holomorphic Poisson structures on the moduli spaces of holomorphic bundles on complex surfaces. The symplectic leaves of the latter are classified by restrictions of the bundles to certain divisors. This can be regarded as fixing a "complex analogue of the holonomy" of a connection along a "complex analogue of the boundary" in analogy with the real case.

  10. Linkages between terrestrial ecosystems and the atmosphere

    Science.gov (United States)

    Bretherton, Francis; Dickinson, Robert E.; Fung, Inez; Moore, Berrien, III; Prather, Michael; Running, Steven W.; Tiessen, Holm

    1992-01-01

    The primary research issue in understanding the role of terrestrial ecosystems in global change is analyzing the coupling between processes with vastly differing rates of change, from photosynthesis to community change. Representing this coupling in models is the central challenge to modeling the terrestrial biosphere as part of the earth system. Terrestrial ecosystems participate in climate and in the biogeochemical cycles on several temporal scales. Some of the carbon fixed by photosynthesis is incorporated into plant tissue and is delayed from returning to the atmosphere until it is oxidized by decomposition or fire. This slower (i.e., days to months) carbon loop through the terrestrial component of the carbon cycle, which is matched by cycles of nutrients required by plants and decomposers, affects the increasing trend in atmospheric CO2 concentration and imposes a seasonal cycle on that trend. Moreover, this cycle includes key controls over biogenic trace gas production. The structure of terrestrial ecosystems, which responds on even longer time scales (annual to century), is the integrated response to the biogeochemical and environmental constraints that develop over the intermediate time scale. The loop is closed back to the climate system since it is the structure of ecosystems, including species composition, that sets the terrestrial boundary condition in the climate system through modification of surface roughness, albedo, and, to a great extent, latent heat exchange. These separate temporal scales contain explicit feedback loops which may modify ecosystem dynamics and linkages between ecosystems and the atmosphere. The long-term change in climate, resulting from increased atmospheric concentrations of greenhouse gases (e.g., CO2, CH4, and nitrous oxide (N2O)) will further modify the global environment and potentially induce further ecosystem change. Modeling these interactions requires coupling successional models to biogeochemical models to

  11. Cognitive Neuroscience in Space

    Directory of Open Access Journals (Sweden)

    Gabriel G. De la Torre

    2014-07-01

    Full Text Available Humans are the most adaptable species on this planet, able to live in vastly different environments on Earth. Space represents the ultimate frontier and a true challenge to human adaptive capabilities. As a group, astronauts and cosmonauts are selected for their ability to work in the highly perilous environment of space, giving their best. Terrestrial research has shown that human cognitive and perceptual motor performances deteriorate under stress. We would expect to observe these effects in space, which currently represents an exceptionally stressful environment for humans. Understanding the neurocognitive and neuropsychological parameters influencing space flight is of high relevance to neuroscientists, as well as psychologists. Many of the environmental characteristics specific to space missions, some of which are also present in space flight simulations, may affect neurocognitive performance. Previous work in space has shown that various psychomotor functions degrade during space flight, including central postural functions, the speed and accuracy of aimed movements, internal timekeeping, attentional processes, sensing of limb position and the central management of concurrent tasks. Other factors that might affect neurocognitive performance in space are illness, injury, toxic exposure, decompression accidents, medication side effects and excessive exposure to radiation. Different tools have been developed to assess and counteract these deficits and problems, including computerized tests and physical exercise devices. It is yet unknown how the brain will adapt to long-term space travel to the asteroids, Mars and beyond. This work represents a comprehensive review of the current knowledge and future challenges of cognitive neuroscience in space from simulations and analog missions to low Earth orbit and beyond.

  12. Analogue Simulation of human and psychosocial factors for MoonMars bases

    Science.gov (United States)

    Davidová, Lucie; Foing, Bernard

    2017-04-01

    Several courageous plans regarding future human space exploration have been proposed. Both main future targets, ESA's Moon village, as well as journey to Mars represent huge challenge for humans. Appropriate research on psychological aspects of humans in extreme conditions is needed. Analogue simulations represent valuable source of information that help us to understand how to provide an adequate support to astronauts in specific conditions of isolation and limited resources. The psychosocial investigation was designed to builds on combination of several methods based on subjective as well as objective assessments, namely observation, sociomapping, content analysis of interviews etc. Research on several simulations provided lessons learned and various insights. The attention was paid particularly to the interpersonal interactions among crew members, intragroup as well as intergroup communication, cooperation, and performance. This comprehensive approach enables early detection of hidden structures and potential insufficiencies of an astronaut team. The sociomapping of interpersonal communication as well as analysis of interviews with participants revealed insufficiencies especially in communication between the analogue astronauts and mission control. Another important finding was gain by investigation of the relationship between the astronaut crew and mission control. Astronauts low trust to mission control can have a great negative impact to the performance and well-being of astronauts. The findings of the psychosocial studies are very important for designing astronaut training and planning future mission.

  13. Properties of the single Jovian planet population and the pursuit of Solar system analogues

    Science.gov (United States)

    Agnew, Matthew T.; Maddison, Sarah T.; Horner, Jonathan

    2018-04-01

    While the number of exoplanets discovered continues to increase at a rapid rate, we are still to discover any system that truly resembles the Solar system. Existing and near future surveys will likely continue this trend of rapid discovery. To see if these systems are Solar system analogues, we will need to efficiently allocate resources to carry out intensive follow-up observations. We seek to uncover the properties and trends across systems that indicate how much of the habitable zone is stable in each system to provide focus for planet hunters. We study the dynamics of all known single Jovian planetary systems, to assess the dynamical stability of the habitable zone around their host stars. We perform a suite of simulations of all systems where the Jovian planet will interact gravitationally with the habitable zone, and broadly classify these systems. Besides the system's mass ratio (Mpl/Mstar), and the Jovian planet's semi-major axis (apl) and eccentricity (epl), we find that there are no underlying system properties which are observable that indicate the potential for planets to survive within the system's habitable zone. We use Mpl/Mstar, apl and epl to generate a parameter space over which the unstable systems cluster, thus allowing us to predict which systems to exclude from future observational or numerical searches for habitable exoplanets. We also provide a candidate list of 20 systems that have completely stable habitable zones and Jovian planets orbiting beyond the habitable zone as potential first order Solar system analogues.

  14. The Orléans-Lithothèque - an analogue rockstore for in situ missions

    Science.gov (United States)

    Bost, Nicolas; Westall, Frances; Ramboz, Claire

    2010-05-01

    The Orléans-Lithothèque - an analogue rockstore for in situ missions Nicolas Bost, Frances Westall, Claire Ramboz, Axelle Hubert, Derek Pullan, Beda Hofmann, Elisabeth Vergès, Michel Viso, Jorge Vago, Christelle Briois, Bruno Scaillet, Michel Tagger Instruments for in-situ missions to extraterrestrial bodies should ideally be cross calibrated using a common suite of relevant materials. Such multi-instrument calibration would enable a better comparison of instrument performances during the mission, as well as aid in the interpretation of the in-situ measurements. At the CNRS in Orléans, the Observatoire des Sciences de l'Univers de la region Centre is creating a collection of well-characterised rocks that will be available for testing and calibrating instruments to be flown on space missions. The characteristics of the collection's analogue materials will be described in an online database. In view of the upcoming 2018 ExoMars rover mission, we are concentrating initially on materials of direct relevance to Mars. The initial collection includes basalts (ultramafic, weathered, andesitic, hydrothermally-silicified); sediments (volcanic, biolaminated, banded iron formation); and minerals (silica, evaporites, clays, Fe oxides). This set of samples will be augmented with time. All samples will be characterised petrographically, petrologically, and geochemically using the types of analyses likely to be performed during an in-situ mission: hand specimen description, optical microscopy, mineralogical analysis (XRD, Raman and IR spectrometry), elemental analysis (EDX, microprobe, ICP) and organics analysis (Raman, pyr-GCMS).

  15. Synthesis, DNA interaction and antimicrobial activities of three rimantadine analogues

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bing-Mi; Zhang, Jun [Department of Pharmacy, Liaoning University, Shenyang 110036 (China); Wang, Xin, E-mail: wangxinlnu@163.com [Department of Pharmacy, Liaoning University, Shenyang 110036 (China); Zhang, Li-Ping; Liu, Yang [Department of Pharmacy, Liaoning University, Shenyang 110036 (China); Niu, Hua-Ying [Jinan Dachpharm Development Co., Ltd., Jinan 250100 (China); Liu, Bin, E-mail: liubinzehao@163.com [Department of Pharmacy, Liaoning University, Shenyang 110036 (China)

    2015-03-15

    The interactions of three rimantadine analogues (RAs) with calf thymus deoxyribonucleic acid (ct-DNA) in buffer solution (pH 7.4) were investigated using berberine (BR) as a probe by various methods. Fluorescence studies revealed that the RAs interacted with DNA in vitro and the quenchings were all static. Furthermore, the binding modes of these compounds to DNA were disclosed as groove binding supported by absorption spectroscopy, viscosity measurement and denatured DNA experiment. The antimicrobial activities of the RAs were also evaluated in Staphylococcus aureus and Escherichia coli, and they all exhibited good bacteriostasic effects. The results might provide an important reference for investigation of the molecular mechanism associated with the DNA binding of the RAs. - Highlights: • Three rimantadine analogues were synthesized. • The RAs effectively quenched the intrinsic fluorescence of DNA via a static combination. • These analogues can bind to DNA via groove binding mode. • The antimicrobial activities of three analogues were also evaluated by the disk diffusion method.

  16. Are structural analogues to bisphenol A a safe alternative?

    DEFF Research Database (Denmark)

    Rosenmai, Anna Kjerstine; Dybdahl, Marianne; Pedersen, Gitte Alsing

    2013-01-01

    of which are found in foods and have been measured in humans. Due to the structural analogy there is an inherent risk that these compounds may lead to similar effects as BPA. The aim of this study was to characterize the toxicological profile of BPA and the five analogues using in vitro assays assessing...

  17. A new analogue of fatty alcohol from Tamarix hampeana L.

    Science.gov (United States)

    Aykac, Ahmet; Akgül, Yurdanur

    2010-01-01

    New analogues of a long-chain secondary alcohol (1) and laserine (2) were isolated from the flowers of Tamarix hampeana L. The isolated compounds were identified using 1D and 2D NMR, LCMS/APCI, and chemical methods. Laserine was isolated for the first time from T. hampeana L.

  18. Cytotoxicity of natural ginseng glycosides and semisynthetic analogues

    NARCIS (Netherlands)

    Atopkina, LN; Malinovskaya, GV; Elyakov, GB; Uvarova, NI; Woerdenbag, HJ; Koulman, A; Potier, P

    The cytotoxicity of natural glycosides from Ginseng, semisynthetic analogues and related triterpenes of the dammarane series, isolated from the leaves of the Far-East species of the genus Betula was studied in order to elucidate structure-activity relationships. Some of the compounds studied were

  19. Influence of Bakuchiol, a JH analogue from Bemchi ( Psoralea ...

    African Journals Online (AJOL)

    The influence of a juvenile hormone analogue (JHA), bakuchiol on the silk yield of silkworm, Bombyx mori L. was studied involving two popular commercial hybrids, KA x NB4D2 (bivoltine x bivoltine) and PM x NB4D2 (multivoltine x bivoltine). The compound was administered topically to 5th instars at 24, 48, 72 and 96 h as ...

  20. Difference in brain activations during appreciating paintings and photographic analogues

    Directory of Open Access Journals (Sweden)

    Yoshinori eMizokami

    2014-07-01

    Full Text Available Several studies have investigated neural correlates of aesthetic appreciation for paintings but to date the findings have been heterogeneous. This heterogeneity may be attributed to previous studies’ measurement of aesthetic appreciation of not only the beauty of paintings but also the beauty of motifs of the paintings. In order to better elucidate the beauty of paintings, it seems necessary to compare aesthetic appreciation of paintings and photographic analogues which included corresponding real images. We prepared for famous painters’ pictures and their photographic analogues which were set up to resemble each painting in order to investigate the hypothesis that there exist specific neural correlates associated with the aesthetic appreciation for paintings. Forty-four subjects participated in functional magnetic resonance study which required comparisons of aesthetic appreciation of paintings of still life and landscape versus photographic analogues including corresponding real images of still life and landscape. Bilateral cuneus and the left lingual gyrus were activated in the comparison of aesthetic appreciation of paintings versus photographic analogues. In conclusion, the present findings suggest a possibility of the existence of specific neural correlates associated with the aesthetic appreciation for paintings and that bilateral cuneus and the left lingual gyrus may be involved.

  1. Trehalose Analogues: Latest Insights in Properties and Biocatalytic Production

    Directory of Open Access Journals (Sweden)

    Maarten Walmagh

    2015-06-01

    Full Text Available Trehalose (α-d-glucopyranosyl α-d-glucopyranoside is a non-reducing sugar with unique stabilizing properties due to its symmetrical, low energy structure consisting of two 1,1-anomerically bound glucose moieties. Many applications of this beneficial sugar have been reported in the novel food (nutricals, medical, pharmaceutical and cosmetic industries. Trehalose analogues, like lactotrehalose (α-d-glucopyranosyl α-d-galactopyranoside or galactotrehalose (α-d-galactopyranosyl α-d-galactopyranoside, offer similar benefits as trehalose, but show additional features such as prebiotic or low-calorie sweetener due to their resistance against hydrolysis during digestion. Unfortunately, large-scale chemical production processes for trehalose analogues are not readily available at the moment due to the lack of efficient synthesis methods. Most of the procedures reported in literature suffer from low yields, elevated costs and are far from environmentally friendly. “Greener” alternatives found in the biocatalysis field, including galactosidases, trehalose phosphorylases and TreT-type trehalose synthases are suggested as primary candidates for trehalose analogue production instead. Significant progress has been made in the last decade to turn these into highly efficient biocatalysts and to broaden the variety of useful donor and acceptor sugars. In this review, we aim to provide an overview of the latest insights and future perspectives in trehalose analogue chemistry, applications and production pathways with emphasis on biocatalysis.

  2. An Analysis of an Autoclitic Analogue in Pigeons

    Science.gov (United States)

    Kuroda, Toshikazu; Lattal, Kennon A.; García-Penagos, Andrés

    2014-01-01

    Using a conditional discrimination procedure, pigeons were exposed to a nonverbal analogue of qualifying autoclitics such as "definitely" and "maybe." It has been suggested that these autoclitics are similar to tacts except that they are under the control of private discriminative stimuli. Instead of the conventional assumption…

  3. Trehalose Analogues: Latest Insights in Properties and Biocatalytic Production

    Science.gov (United States)

    Walmagh, Maarten; Zhao, Renfei; Desmet, Tom

    2015-01-01

    Trehalose (α-d-glucopyranosyl α-d-glucopyranoside) is a non-reducing sugar with unique stabilizing properties due to its symmetrical, low energy structure consisting of two 1,1-anomerically bound glucose moieties. Many applications of this beneficial sugar have been reported in the novel food (nutricals), medical, pharmaceutical and cosmetic industries. Trehalose analogues, like lactotrehalose (α-d-glucopyranosyl α-d-galactopyranoside) or galactotrehalose (α-d-galactopyranosyl α-d-galactopyranoside), offer similar benefits as trehalose, but show additional features such as prebiotic or low-calorie sweetener due to their resistance against hydrolysis during digestion. Unfortunately, large-scale chemical production processes for trehalose analogues are not readily available at the moment due to the lack of efficient synthesis methods. Most of the procedures reported in literature suffer from low yields, elevated costs and are far from environmentally friendly. “Greener” alternatives found in the biocatalysis field, including galactosidases, trehalose phosphorylases and TreT-type trehalose synthases are suggested as primary candidates for trehalose analogue production instead. Significant progress has been made in the last decade to turn these into highly efficient biocatalysts and to broaden the variety of useful donor and acceptor sugars. In this review, we aim to provide an overview of the latest insights and future perspectives in trehalose analogue chemistry, applications and production pathways with emphasis on biocatalysis. PMID:26084050

  4. An azumamide C analogue without the zinc-binding functionality

    DEFF Research Database (Denmark)

    Villadsen, Jesper; Kitir, Betül; Wich, Kathrine

    2014-01-01

    + - coordinating moiety. Herein, we describe the synthesis of an azumamide analogue lacking its native Zn 2+ -binding group and evaluation of its inhibitory activity against recombinant human HDAC1 – 11. Furthermore, kinetic investigation of the inhibitory mechanism of both parent natural product and synthetic...

  5. Evaluation of the antibacterial spectrum of drosocin analogues

    NARCIS (Netherlands)

    Bikker, F.J.; Kaman-van Zanten, W.E.; Vries-van de Ruit, A.M.B.C. de; Voskamp-Visser, I.; Hooft, P.A.V. van; Mars-Groenendijk, R.H.; Visser, P.C. de; Noort, D.

    2006-01-01

    Drosocin is a 19-mer, cationic antimicrobial peptide from Drosophila melanogaster. The aim of the study was to examine the antibacterial spectrum of unglycosylated drosocin analogues. Furthermore, the amino acid sequence of DnaK, drosocin's intracellular target, from susceptible species was aligned

  6. Research on uranium deposits as analogues of radioactive waste repositories

    International Nuclear Information System (INIS)

    Hardy, C.J.

    1987-01-01

    The disposal of highly radioactive waste deep underground in suitable geological formations is proposed by many countries to protect public health and safety. The study of natural analogues of nuclear waste repositories is one method of validating mathematical models and assuring that a proposed repository site and design will be safe. (author)

  7. Scattering matrices and expansion coefficients of martian analogue palagonite particles

    NARCIS (Netherlands)

    Laan, E.C.; Volten, H.; Stam, D.M.; Muñoz, O.; Hovenier, J.W.; Roush, T.L.

    2009-01-01

    We present measurements of ratios of elements of the scattering matrix of martian analogue palagonite particles for scattering angles ranging from 3° to 174° and a wavelength of 632.8 nm. To facilitate the use of these measurements in radiative transfer calculations we have devised a method that

  8. Reasoning by analogy: rational foundation of natural analogue studies

    International Nuclear Information System (INIS)

    Petit, J.-C.

    1992-01-01

    Long-term extrapolations concerning the safety of a nuclear waste repository cannot be satisfactorily made on the sole basis of short-term laboratory investigations. Most nuclear countries have hence developed an approach relying on the following research directions: 1. laboratory experiments; 2. in situ testing; 3. modeling; and 4. natural analogues, which are the only means by which very slow mechanisms can be identified and by which long-term predictions of models can be tested for pertinence (if not truly validated). Although the field of natural analogues has grown very rapidly in recent years, receiving support from varied specialists and institutions involved in radioactive waste disposal, there is not yet a full consensus on their actual usefulness. More problematic is the criticism sometimes made that analogical reasoning is not ''true science'' and that information retrieved from the study of natural analogues will always remain questionable. The present paper gives some clues about the exact status of reasoning by analogy, compared to more ''scientific'' ways of deriving information from investigated systems. It is not a thorough discussion of this very complex, and by far too philosophical issue but we hope, at least, to present to readers of papers devoted to natural analogue studies arguments showing that this approach has some sound foundation. (author)

  9. Using natural analogue studies in the secondary science curriculum

    International Nuclear Information System (INIS)

    Ebert, E.K.

    1995-01-01

    This paper discusses an atomic theory unit of a high school chemistry course taught in Nevada. The unit is based on the application of natural analogues to nuclear waste issues. The paper focuses on the students' reactions to the subject material

  10. A Short Review on Cardiotonic Steroids and Their Aminoguanidine Analogues

    Directory of Open Access Journals (Sweden)

    Arturo San Feliciano

    2000-01-01

    Full Text Available A short review on cardiotonic steroids and their analogues is presented. The natural, semisynthetic and synthetic derivatives, as well as their mechanism of action and structure-activity relationships are shown, with a special reference to aminoguanidine derivatives.

  11. Design and synthesis of epicocconone analogues with improved fluorescence properties.

    Science.gov (United States)

    Peixoto, Philippe A; Boulangé, Agathe; Ball, Malcolm; Naudin, Bertrand; Alle, Thibault; Cosette, Pascal; Karuso, Peter; Franck, Xavier

    2014-10-29

    Epicocconone is a natural latent fluorophore that is widely used in biotechnology because of its large Stokes shift and lack of fluorescence in its unconjugated state. However, the low photostability and quantum yields of epicocconone have limited its wider use, and in the absence of a total synthesis, this limitation has been a long-standing problem. Here we report a general strategy for the synthesis of epicocconone analogues that relies on a 2-iodoxybenzoic acid-mediated dearomatization and on the replacement of the triene tail of the natural product by an aromatic ring. This design element is general and the synthesis is straightforward, providing ready access to libraries of polyfunctional fluorophores with long Stokes shifts based on the epicocconone core. Our structural modifications resulted in analogues with increased photostability and quantum yields compared with the natural product. Staining proteomic gels with these new analogues showed significant lowering of the detection limit and a 30% increase in the number of low-abundance proteins detected. These epiccoconone analogues will substantially improve the discovery rate of biomarker needles in the proteomic haystack.

  12. Evaluative comparison of palm wine analogue and oil palm wine ...

    African Journals Online (AJOL)

    0.05 and P=0.01) in colour, odour, effervescence and general acceptability between palm wine analogue and oil palm wine. While there also was no significant difference in the tastes and balance of sweetness at P=0.01, a slight difference ...

  13. Vitamin E analogues and immune response in cancer treatment

    Czech Academy of Sciences Publication Activity Database

    Tomasetti, M.; Neužil, Jiří

    2007-01-01

    Roč. 76, - (2007), s. 463-491 ISSN 0083-6729 Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50520701 Keywords : vitamin E analogues * inducers of apoptosis * immune surveillance Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.889, year: 2007

  14. Analogue Building Blocks Based on Digital CMOS Gates

    DEFF Research Database (Denmark)

    Mucha, Igor

    1996-01-01

    Low-performance analogue circuits built of digital MOS gates are presented. Depending on the threshold voltages of the technology used the final circuits can be operated using low supply voltages. The main advantage using the proposed circuits is the simplicity and ultimate compatibility...... with the design of digital circuits....

  15. Brassinosteroids: Synthesis and activity of some fluoro analogues

    Czech Academy of Sciences Publication Activity Database

    Slavíková, Barbora; Kohout, Ladislav; Buděšínský, Miloš; Swaczynová, Jana; Kasal, Alexander

    2008-01-01

    Roč. 51, č. 13 (2008), s. 3979-3984 ISSN 0022-2623 R&D Projects: GA AV ČR IAA400550609 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z50380511 Keywords : brassinosteroids * fluor o analogues Subject RIV: CC - Organic Chemistry Impact factor: 4.898, year: 2008

  16. Thulium heat sources for space power applications

    International Nuclear Information System (INIS)

    Alderman, C.J.

    1992-05-01

    Reliable power supplies for use in transportation and remote systems will be an important part of space exploration terrestrial activities. A potential power source is available in the rare earth metal, thulium. Fuel sources can be produced by activating Tm-169 targets in the space station reactor. The resulting Tm-170 heat sources can be used in thermoelectric generators to power instrumentation and telecommunications located at remote sites such as weather stations. As the heat source in a dynamic Sterling or Brayton cycle system, the heat source can provide a lightweight power source for rovers or other terrestrial transportation systems

  17. Evolution of Herbivory in Terrestrial Vertebrates

    Science.gov (United States)

    Sues, Hans-Dieter

    2000-08-01

    Although herbivory probably first appeared over 300 million years ago, it only became established as a common feeding strategy during Late Permian times. Subsequently, herbivory evolved in numerous lineages of terrestrial vertebrates, and the acquisition of this mode of feeding was frequently associated with considerable evolutionary diversification in those lineages. This book represents a comprehensive overview of the evolution of herbivory in land-dwelling amniote tetrapods in recent years. In Evolution of Herbivory in Terrestrial Vertebrates, leading experts review the evolutionary history and structural adaptations required for feeding on plants in the major groups of land-dwelling vertebrates, especially dinosaurs and ungulate mammals. As such, this volume will be the definitive reference source on this topic for evolutionary biologists and vertebrate paleontologists.

  18. The overlooked terrestrial impacts of mountaintop mining

    Science.gov (United States)

    Wickham, James; Wood, Petra Bohall; Nicholson, Matthew C.; Jenkins, William; Druckenbrod, Daniel; Suter, Glenn W.; Strager, Michael P.; Mazzarella, Christine; Galloway, Walter; Amos, John

    2013-01-01

    Ecological research on mountaintop mining has been focused on aquatic impacts because the overburden (i.e., the mountaintop) is disposed of in nearby valleys, which leads to a wide range of water-quality impacts on streams. There are also numerous impacts on the terrestrial environment from mountaintop mining that have been largely overlooked, even though they are no less wide ranging, severe, and multifaceted. We review the impacts of mountaintop mining on the terrestrial environment by exploring six broad themes: (1) the loss of topographic complexity, (2) forest loss and fragmentation, (3) forest succession and soil loss, (4) forest loss and carbon sequestration, (5) biodiversity, and (6) human health and well-being.

  19. Space Resources Roundtable 2

    Science.gov (United States)

    Ignatiev, A.

    2000-01-01

    Contents include following: Developing Technologies for Space Resource Utilization - Concept for a Planetary Engineering Research Institute. Results of a Conceptual Systems Analysis of Systems for 200 m Deep Sampling of the Martian Subsurface. The Role of Near-Earth Asteroids in Long-Term Platinum Supply. Core Drilling for Extra-Terrestrial Mining. Recommendations by the "LSP and Manufacturing" Group to the NSF-NASA Workshop on Autonomous Construction and Manufacturing for Space Electrical Power Systems. Plasma Processing of Lunar and Planetary Materials. Percussive Force Magnitude in Permafrost. Summary of the Issues Regarding the Martian Subsurface Explorer. A Costing Strategy for Manufacturing in Orbit Using Extraterrestrial Resources. Mine Planning for Asteroid Orebodies. Organic-based Dissolution of Silicates: A New Approach to Element Extraction from LunarRegohth. Historic Frontier Processes Active in Future Space-based Mineral Extraction. The Near-Earth Space Surveillance (NIESS) Mission: Discovery, Tracking, and Characterization of Asteroids, Comets, and Artificial Satellites with a microsatellite. Privatized Space Resource Property Ownership. The Fabrication of Silicon Solar Cells on the Moon Using In-Situ Resources. A New Strategy for Exploration Technology Development: The Human Exploration and Development of Space (HEDS) Exploratiori/Commercialization Technology Initiative. Space Resources for Space Tourism. Recovery of Volatiles from the Moon and Associated Issues. Preliminary Analysis of a Small Robot for Martian Regolith Excavation. The Registration of Space-based Property. Continuous Processing with Mars Gases. Drilling and Logging in Space; An Oil-Well Perspective. LORPEX for Power Surges: Drilling, Rock Crushing. An End-To-End Near-Earth Asteroid Resource Exploitation Plan. An Engineering and Cost Model for Human Space Settlement Architectures: Focus on Space Hotels and Moon/Mars Exploration. The Development and Realization of a Silicon-60-based

  20. MAFF monitoring of the terrestrial environment

    International Nuclear Information System (INIS)

    Sherlock, J.C.

    1993-01-01

    This paper addresses the food surveillance programme of the Ministry of Agriculture, Fisheries and Food (MAFF), in particular the Terrestrial Radioactivity Monitoring Programme (TRAMP) and the estimation of dietary intake of radionuclides. To define the surveillance programme the following issues need to be decided upon: 1) the type of food which should be analysed; 2) the nature of the contaminants which should be analysed; and 3) the geographical location from which the food samples should be taken. (author)

  1. Astrophysical and terrestrial neutrinos in Supernova detectors

    International Nuclear Information System (INIS)

    Lagage, P.O.

    1985-09-01

    Supernova (SN) explosions are the place of very fundamental phenomena, whose privileged messengers are neutrinos. But such events are very rare. Then, SN detection has to be combined with other purposes. The recent developments of SN detectors have been associated with developments of underground particle physics (proton decay, monopoles ...). But here, I will restrict myself to discuss the possibilities for a supernova detector to be sensitive to other sources of neutrinos, astrophysical or terrestrial

  2. Documentation of Bridges by Terrestrial Laser Scanner

    OpenAIRE

    Truong-Hong, Linh; Laefer, Debra F.

    2015-01-01

    Bridge structures are subjected to deterioration due to excessive usage, overloading, and aging material. For the last two decades, a significant amount research has been developed for collecting data for structural health monitoring. Yet, visual investigation with an on-site inspector remains the predominant method. This is true despite the highly subjective and time consuming aspects of this approach. Alternatively, terrestrial laser scanning can acquire surface details of structures quickl...

  3. Global change and terrestrial hydrology - A review

    Science.gov (United States)

    Dickinson, Robert E.

    1991-01-01

    This paper reviews the role of terrestrial hydrology in determining the coupling between the surface and atmosphere. Present experience with interactive numerical simulation is discussed and approaches to the inclusion of land hydrology in global climate models ae considered. At present, a wide range of answers as to expected changes in surface hydrology is given by nominally similar models. Studies of the effects of tropical deforestation and global warming illustrate this point.

  4. Furostanol and Spirostanol Saponins from Tribulus terrestris

    Directory of Open Access Journals (Sweden)

    Zhen-Fang Wang

    2016-03-01

    Full Text Available Twelve new steroidal saponins, including eleven furostanol saponins, terrestrinin J–T (1–11, and one spirostanol saponin, terrestrinin U (12, together with seven known steroidal saponins 13–19 were isolated from T. terrestris. The structures of the new compounds were established on the basis of spectroscopic data, including 1D and 2D NMR and HRESIMS, and comparisons with published data.

  5. Comparison of overlay metrology with analogue and digital cameras

    Science.gov (United States)

    Rigden, Timothy C.; Soroka, Andrew J.; Binns, Lewis A.

    2005-05-01

    Overlay metrology is a very demanding image processing application; current applications are achieving dynamic precision of one hundredth of a pixel or better. As such it requires an accurate image acquisition system, with minimal distortions. Distortions can be physical (e.g. pixel size / shape) or electronic (e.g. clock skew) in nature. They can also affect the image shape, or the gray level intensity of individual pixels, the former causing severe problems to pattern recognition and measurement algorithms, the latter having an adverse effect primarily on the measurement itself. This paper considers the artifacts that are present in a particular analogue camera, with a discussion on how these artifacts translate into a reduction of overlay metrology performance, in particular their effect on precision and tool induced shift (TIS). The observed effects include, but are not limited to, banding and interlacing. This camera is then compared to two digital cameras. The first of these operates at the same frame rate as the analogue camera, and is found to have fewer distortions than the analogue camera. The second camera operates with a frame rate twice that of the other two. It is observed that this camera does not exhibit the distortions of the analogue camera, but instead has some very specific problems, particularly with regards to noise. The quantitative data on the effect on precision and TIS under a wide variety of conditions, is presented. These show that while it is possible to achieve metrology-capable images using an analogue camera, it is preferable to use a digital camera, both from the perspective of overall system performance, and overall system complexity.

  6. Neurochemical binding profiles of novel indole and benzofuran MDMA analogues.

    Science.gov (United States)

    Shimshoni, Jakob A; Winkler, Ilan; Golan, Ezekiel; Nutt, David

    2017-01-01

    3,4-Methylenedioxy-N-methylamphetamine (MDMA) has been shown to be effective in the treatment of post-traumatic stress disorder (PTSD) in numerous clinical trials. In the present study, we have characterized the neurochemical binding profiles of three MDMA-benzofuran analogues (1-(benzofuran-5-yl)-propan-2-amine, 5-APB; 1-(benzofuran-6-yl)-N-methylpropan-2-amine, 6-MAPB; 1-(benzofuran-5-yl)-N-methylpropan-2-amine, 5-MAPB) and one MDMA-indole analogue (1-(1H-indol-5-yl)-2-methylamino-propan-1-ol, 5-IT). These compounds were screened as potential second-generation anti-PTSD drugs, against a battery of human and non-human receptors, transporters, and enzymes, and their potencies as 5-HT 2 receptor agonist and monoamine uptake inhibitors determined. All MDMA analogues displayed high binding affinities for 5-HT 2a,b,c and NE α2 receptors, as well as significant 5-HT, DA, and NE uptake inhibition. 5-APB revealed significant agonist activity at the 5-HT 2a,b,c receptors, while 6-MAPB, 5-MAPB, and 5-IT exhibited significant agonist activity at the 5-HT 2c receptor. There was a lack of correlation between the results of functional uptake and the monoamine transporter binding assay. MDMA analogues emerged as potent and selective monoamine oxidase A inhibitors. Based on 6-MAPB favorable pharmacological profile, it was further subjected to IC 50 determination for monoamine transporters. Overall, all MDMA analogues displayed higher monoamine receptor/transporter binding affinities and agonist activity at the 5-HT 2a,c receptors as compared to MDMA.

  7. Analogue model studies of induction effects at auroral latitudes

    Directory of Open Access Journals (Sweden)

    A. Viljanen

    1995-11-01

    Full Text Available In addition to field observations and numerical models, geomagnetic induction effects can be studied by scaled analogue model experiments. We present here results of analogue model studies of the auroral electrojet with an Earth model simulating the Arctic Ocean and inland conductivity structures in northern Fennoscandia. The main elements of the analogue model used were salt water simulating the host rock, an aluminium plate corresponding to the ocean and graphite pieces producing the inland highly conducting anomalies. The electrojet was a time-harmonic line current flowing at a (simulated height of 100 km above northern Fennoscandia. The period simulated was 9 min. The analogue model results confirmed the well-known rapid increase of the vertical field when the coast is approached from the continent. The increase of the horizontal field due to induced ocean currents was demonstrated above the ocean, as well as the essentially negligible effect of these currents on the horizontal field on the continent. The behaviour of the magnetic field is explained with a simple two-dimensional thin-sheet model. The range, or the adjustment distance, of the ocean effect inland was found to be some hundreds of kilometers, which also agrees with earlier results of the Siebert-Kertz separation of IMAGE magnetometer data. The modelled inland anomalies evidently had too large conductivities, but on the other hand, their influence decayed on scales of only some tens of kilometers. Analogue model results, thin-sheet calculations, and field observations show that the induction effect on the horizontal magnetic field Bx near the electrojet is negligible. On the other hand, the vertical component Bz is clearly affected by induced currents in the ocean. Evidence of this is the shift of the zero point of Bz 0-1° southwards from the maximum of Bx. The importance of these results are discussed, emphasizing the determination of ionospheric currents.

  8. Strategies for Constraining the Atmospheres of Temperate Terrestrial Planets with JWST

    Science.gov (United States)

    Batalha, Natasha E.; Lewis, Nikole K.; Line, Michael R.; Valenti, Jeff; Stevenson, Kevin

    2018-04-01

    The Transiting Exoplanet Survey Satellite (TESS) is expected to discover dozens of temperate terrestrial planets orbiting M-dwarfs with atmospheres that could be followed up with the James Webb Space Telescope (JWST). Currently, the TRAPPIST-1 system serves as a benchmark for determining the feasibility and resources required to yield atmospheric constraints. We assess these questions and leverage an information content analysis to determine observing strategies for yielding high-precision spectroscopy in transmission and emission. Our goal is to guide observing strategies of temperate terrestrial planets in preparation for the early JWST cycles. First, we explore JWST’s current capabilities and expected spectral precision for targets near the saturation limits of specific modes. In doing so, we highlight the enhanced capabilities of high-efficiency readout patterns that are being considered for implementation in Cycle 2. We propose a partial saturation strategy to increase the achievable precision of JWST's NIRSpec Prism. We show that JWST has the potential to detect the dominant absorbing gas in the atmospheres of temperate terrestrial planets by the 10th transit using transmission spectroscopy techniques in the near-infrared (NIR). We also show that stacking ⪆10 transmission spectroscopy observations is unlikely to yield significant improvements in determining atmospheric composition. For emission spectroscopy, we show that the MIRI Low Resolution Spectroscopy (LRS) is unlikely to provide robust constraints on the atmospheric composition of temperate terrestrial planets. Higher-precision emission spectroscopy at wavelengths longward of those accessible to MIRI LRS, as proposed in the Origins Space Telescope concept, could help improve the constraints on molecular abundances of temperate terrestrial planets orbiting M-dwarfs.

  9. Insecticidal action of synthetic girgensohnine analogues and essential oils on Rhodnius prolixus (Hemiptera: Reduviidae

    Directory of Open Access Journals (Sweden)

    Juliana Cuadros

    2017-03-01

    Conclusion: Synthetic girgensohnine analogues, and C. flexuosus and C. sinensis essential oils showed insecticidal activity in R. prolixus. Analogue 3 showed the greatest insecticidal activity among all molecules and oils evaluated under our laboratory conditions.

  10. The impact of watching educational video clips on analogue patients' physiological arousal and information recall

    NARCIS (Netherlands)

    Bruinessen, I.R. van; Ende, I.T. van den; Visser, L.N.; Dulmen, S. van

    2016-01-01

    OBJECTIVE: Investigating the influence of watching three educational patient-provider interactions on analogue patients' emotional arousal and information recall. METHODS: In 75 analogue patients the emotional arousal was measured with physiological responses (electrodermal activity and heart rate)

  11. The impact of watching educational video clips on analogue patients' physiological arousal and information recall

    NARCIS (Netherlands)

    van Bruinessen, I. R.; van den Ende, I. T. A.; Visser, L. N. C.; van Dulmen, S.

    2016-01-01

    Investigating the influence of watching three educational patient-provider interactions on analogue patients' emotional arousal and information recall. In 75 analogue patients the emotional arousal was measured with physiological responses (electrodermal activity and heart rate) and self-reported

  12. Altering the communication networks of multispecies microbial systems using a diverse toolbox of AI-2 analogues.

    Science.gov (United States)

    Gamby, Sonja; Roy, Varnika; Guo, Min; Smith, Jacqueline A I; Wang, Jingxin; Stewart, Jessica E; Wang, Xiao; Bentley, William E; Sintim, Herman O

    2012-06-15

    There have been intensive efforts to find small molecule antagonists for bacterial quorum sensing (QS) mediated by the "universal" QS autoinducer, AI-2. Previous work has shown that linear and branched acyl analogues of AI-2 can selectively modulate AI-2 signaling in bacteria. Additionally, LsrK-dependent phosphorylated analogues have been implicated as the active inhibitory form against AI-2 signaling. We used these observations to synthesize an expanded and diverse array of AI-2 analogues, which included aromatic as well as cyclic C-1-alkyl analogues. Species-specific analogues that disrupted AI-2 signaling in Escherichia coli and Salmonella typhimurium were identified. Similarly, analogues that disrupted QS behaviors in Pseudomonas aeruginosa were found. Moreover, we observed a strong correlation between LsrK-dependent phosphorylation of these acyl analogues and their ability to suppress QS. Significantly, we demonstrate that these analogues can selectively antagonize QS in single bacterial strains in a physiologically relevant polymicrobial culture.

  13. Analogue Electrical Circuit for Simulation of the Duffing-Holmes Equation

    DEFF Research Database (Denmark)

    Tamaseviciute, E.; Tamasevicius, A.; Mykolaitis, G.

    2008-01-01

    An extremely simple second order analogue electrical circuit for simulating the two-well Duffing-Holmes mathematical oscillator is described. Numerical results and analogue electrical simulations are illustrated with the snapshots of chaotic waveforms, phase portraits (Lissajous figures...

  14. The impact of watching educational video clips on analogue patients' physiological arousal and information recall.

    NARCIS (Netherlands)

    Bruinessen, I.R. van; Ende, I.T.A. van den; Visser, I.N.C.; Dulmen, S. van

    2016-01-01

    Objective: Investigating the influence of watching three educational patient–provider interactions on analogue patients’ emotional arousal and information recall. Methods: In 75 analogue patients the emotional arousal was measured with physiological responses (electrodermal activity and heart rate)

  15. Hydrolytic microbial communities in terrestrial ecosystems

    Science.gov (United States)

    Manucharova, Natalia; Chernov, Timofey; Kolcova, Ekaterina; Zelezova, Alena; Lukacheva, Euhenia; Zenova, Galina

    2014-05-01

    Hydrolytic microbial communities in terrestrial ecosystems Manucharova N.A., Chernov T.I., Kolcova E.M., Zelezova A.D., Lukacheva E.G. Lomonosov Moscow State University, Russia Vertical differentiation of terrestrial biogeocenoses is conditioned by the formation of vertical tiers that differ considerably in the composition and structure of microbial communities. All the three tiers, phylloplane, litter and soil, are united by a single flow of organic matter, and are spatially separated successional stages of decomposition of organic substances. Decomposition of organic matter is mainly due to the activity of microorganisms producing enzymes - hydrolase and lyase - which destroy complex organic compounds. Application of molecular biological techniques (FISH) in environmental studies provides a more complete information concerning the taxonomic diversity and potential hydrolytic activity of microbial complexes of terrestrial ecosystems that exist in a wide range of environmental factors (moisture, temperature, redox potential, organic matter). The combination of two molecular biological techniques (FISH and DGGE-analysis of fragments of gene 16S rRNA total amplificate) enables an informative assessment of the differences in the structure of dominant and minor components of hydrolytic complexes formed in different tiers of terrestrial ecosystems. The functional activity of hydrolytic microbial complexes of terrestrial ecosystems is determined by the activity of dominant and minor components, which also have a high gross enzymatic activity. Degradation of biopolymers in the phylloplane is mainly due to the representatives of the Proteobacteria phylogenetic group (classes alpha and beta). In mineral soil horizons, the role of hydrolytic representatives of Firmicutes and Actinobacteria increases. Among the key environmental parameters that determine the functional activity of the hydrolytic (chitinolytic) complex of soil layer (moisture, nutrient supply, successional

  16. Deficiencies in fat-soluble vitamins in long-term users of somatostatin analogue

    NARCIS (Netherlands)

    Fiebrich, H. -B.; van den Berg, G.; Kema, I. P.; Links, T. P.; Kleibeuker, J. H.; van Beek, A. P.; Walenkamp, A. M. E.; Sluiter, W. J.; de Vries, E. G. E.

    2010-01-01

    P>Background Somatostatin analogues are administered to control hormone hypersecretion in acromegaly and carcinoid patients. Somatostatin analogues can increase fat in the stools, which can lead to loss of fat-soluble vitamins. The effect of long-term somatostatin analogue use on vitamin levels

  17. On Using Current Steering Logic in Mixed Analogue-digital Circuits

    DEFF Research Database (Denmark)

    Lehmann, Torsten

    1998-01-01

    The authors investigate power supply noise in mixed analogue-digital circuits, arising from communication between the analogue and digital parts of the circuit. Current steering techniques and proper buffering are used to show which noise currents can be reduced and which cannot. In addition......, a high-swing current steering buffer for driving analogue switches or external digital signals is proposed....

  18. Alligator Rivers Analogue project. Application of scenario development method in evaluation of the Koongarra Analogue. Final Report - Volume 16

    International Nuclear Information System (INIS)

    Skagius, K.; Wingefors, S.

    1992-01-01

    The study of natural analogues has been established as one of the most important methods for validation of concepts and models applied for the assessment of long-term performance of repositories for nuclear waste. The objectives of such studies range from detailed investigations of processes and features on a small scale to attempts of explaining the evolution of whole sites. For studies of specific processes it may well be as important to consider the larger scale settings as boundary conditions. This appreciation of context and an integrated view may be as important for evaluation of most natural analogues as for performance assessments. This is more evident the more the evaluation depends on a knowledge about the evolution of the natural analogue. The attempted formulation of scenarios of the Koongarra Analogue has been based on the external conditions and external features. A rapid weathering of the host rock, i.e. the chlorite schist, is assumed to have started around the onset of the Pleistocene Ice Age (ca 1.6 Ma BP). The eventual oxidation and mobilization of the uranium ore could then have occurred under unsaturated or saturated conditions. This leads to the following major scenarios: (1) Uranyl Phosphates formed under unsaturated conditions, with a periodical evolution of the dispersion fan in conjunction with alternating dry (glacial) and wet (interglacial) periods during the Pleistocene Ice Age; (2) Uranyl Phosphates formed under unsaturated conditions as a single event, taking place either early or late during the Pleistocene Ice Age; (3)Uranyl Phosphates formed under saturated conditions, in conjunction with periods of higher and lower flow due to the climatic cycling. Although the original objectives may not have been fully achieved, this work is believed to contribute to a better understanding of the Koongarra Analogue as well as to give a basis for further scenario work

  19. An analogue of Morse theory for planar linear networks and the generalized Steiner problem

    International Nuclear Information System (INIS)

    Karpunin, G A

    2000-01-01

    A study is made of the generalized Steiner problem: the problem of finding all the locally minimal networks spanning a given boundary set (terminal set). It is proposed to solve this problem by using an analogue of Morse theory developed here for planar linear networks. The space K of all planar linear networks spanning a given boundary set is constructed. The concept of a critical point and its index is defined for the length function l of a planar linear network. It is shown that locally minimal networks are local minima of l on K and are critical points of index 1. The theorem is proved that the sum of the indices of all the critical points is equal to χ(K)=1. This theorem is used to find estimates for the number of locally minimal networks spanning a given boundary set

  20. Raman-Mössbauer-XRD studies of selected samples from "Los Azulejos" outcrop: A possible analogue for assessing the alteration processes on Mars

    Science.gov (United States)

    Lalla, E. A.; Sanz-Arranz, A.; Lopez-Reyes, G.; Sansano, A.; Medina, J.; Schmanke, D.; Klingelhoefer, G.; Rodríguez-Losada, J. A.; Martínez-Frías, J.; Rull, F.

    2016-06-01

    The outcrop of "Los Azulejos" is visible at the interior of the Cañadas Caldera in Tenerife Island (Spain). It exhibits a great variety of alteration processes that could be considered as terrestrial analogue for several geological processes on Mars. This outcrop is particularly interesting due to the content of clays, zeolite, iron oxides, and sulfates corresponding to a hydrothermal alteration catalogued as "Azulejos" type alteration. A detailed analysis by portable and laboratory Raman systems as well as other different techniques such as X-ray diffraction (XRD) and Mössbauer spectroscopy has been carried out (using twin-instruments from Martian lander missions: Mössbauer spectrometer MIMOS-II from the NASA-MER mission of 2001 and the XRD diffractometer from the NASA-MSL Curiosity mission of 2012). The mineral identification presents the following mineral species: magnetite, goethite, hematite, anatase, rutile, quartz, gregoryite, sulfate (thenardite and hexahydrite), diopside, feldspar, analcime, kaolinite and muscovite. Moreover, the in-situ Raman and Micro-Raman measurements have been performed in order to compare the capabilities of the portable system specially focused for the next ESA Exo-Mars mission. The mineral detection confirms the sub-aerial alteration on the surface and the hydrothermal processes by the volcanic fluid circulations in the fresh part. Therefore, the secondary more abundant mineralization acts as the color agent of the rocks. Thus, the zeolite-illite group is the responsible for the bluish coloration, as well as the feldspars and carbonates for the whitish and the iron oxide for the redish parts. The XRD system was capable to detect a minor proportion of pyroxene, which is not visible by Raman and Mössbauer spectroscopy due to the "Azulejos" alteration of the parent material on the outcrop. On the other hand, Mössbauer spectroscopy was capable of detecting different types of iron-oxides (Fe3+/2+-oxide phases). These analyses

  1. 11th International Space Conference on Protection of Materials and Structures from Space Environment

    CERN Document Server

    2017-01-01

    The proceedings published in this book document and foster the goals of the 11th International Space Conference on “Protection of Materials and Structures from Space Environment” ICPMSE-11 to facilitate exchanges between members of the various engineering and science disciplines involved in the development of space materials. Contributions cover aspects of interaction with space environment of LEO, GEO, Deep Space, Planetary environments, ground-based qualification and in-flight experiments, as well as lessons learned from operational vehicles that are closely interrelated to disciplines of atmospheric sciences, solar-terrestrial interactions and space life sciences.

  2. SMILE: A new approach to exploring solar-terrestrial relationships

    Science.gov (United States)

    Branduardi-Raymont, Graziella; Wang, Chi; Steven, Sembay; Dai, Lei; Li, Lei; Donovan, Eric; Sun, Tianran; Kataria, Dhiren; Yang, Huigen; Read, Andrew; Whittaker, Ian; Spanswick, Emma; Sibeck, David; Kuntz, Kip; Escoubet, Philippe; Agnolon, David; Raab, Walfried; Zheng, Janhua

    2017-04-01

    SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) aims to investigate the coupling of the solar wind with the Earth's magnetosphere, and the geospace dynamics that ensue, in a novel and global manner never tried so far. From a highly elliptical and highly inclined polar orbit, SMILE will simultaneously image the soft X-rays produced by solar wind charge exchange to delineate the Earth's magnetic boundaries and polar cusps, image the northern auroral oval in ultraviolet emissions, and measure the solar wind/magnetosheath plasma and magnetic field input. SMILE measurements will inform the science underpinning our still limited understanding of solar-terrestrial relationships and of their fundamental drivers, and will validate both global empirical and first-principle models. For the first time we will be able to trace and link the processes governing magnetopause interactions to those causing charged particle precipitation into the cusps and the remainder of the auroral oval, mapping aspects of the global interaction including the evolution of energy and mass transport. SMILE is a joint space mission between the European Space Agency and the Chinese Academy of Sciences due for launch at the end of 2021. This presentation will cover the science that will be delivered by SMILE and will provide an overview of SMILE's payload and mission development, demonstrating the scientific potential of SMILE through simulations of the data that it will return.

  3. Terrestrial outgoing radiation measurements with small satellite mission

    Science.gov (United States)

    Zhu, Ping; Dewitte, Steven; Karatekin, Ozgur; Chevalier, André; Conscience, Christian

    2015-04-01

    The solar force is the main driver of the Earth's climate. For a balanced climate system, the incoming solar radiation is equal to the sum of the reflected visible and reemitted thermal radiation at top of the atmosphere (TOA). Thus the energy imbalance plays an important role to diagnose the health of nowadays climate. However it remains a challenge to directly track the small Energy imbalance in Earth's Radiation Budget (EIERB) from space due to the complicities of the Earth's climate system and the limitation on long term stability of space instrument. The terrestrial outgoing radiation (TOR) has been recoded with a Bolometric Oscillation Sensor onboard PICAD microsatellite. In this presentation, we will report the three years TOR observed with PICARD-BOS and its further comparison with the CERES product. However the data acquired from this mission is still not enough to derive the EIERB. But the heritage gained from this experiment shields a light on the EIERB tracking with the small satellite even a cubesat mission.

  4. Automated Terrestrial EMI Emitter Detection, Classification, and Localization

    Science.gov (United States)

    Stottler, R.; Ong, J.; Gioia, C.; Bowman, C.; Bhopale, A.

    Clear operating spectrum at ground station antenna locations is critically important for communicating with, commanding, controlling, and maintaining the health of satellites. Electro Magnetic Interference (EMI) can interfere with these communications, so it is extremely important to track down and eliminate sources of EMI. The Terrestrial RFI-locating Automation with CasE based Reasoning (TRACER) system is being implemented to automate terrestrial EMI emitter localization and identification to improve space situational awareness, reduce manpower requirements, dramatically shorten EMI response time, enable the system to evolve without programmer involvement, and support adversarial scenarios such as jamming. The operational version of TRACER is being implemented and applied with real data (power versus frequency over time) for both satellite communication antennas and sweeping Direction Finding (DF) antennas located near them. This paper presents the design and initial implementation of TRACER’s investigation data management, automation, and data visualization capabilities. TRACER monitors DF antenna signals and detects and classifies EMI using neural network technology, trained on past cases of both normal communications and EMI events. When EMI events are detected, an Investigation Object is created automatically. The user interface facilitates the management of multiple investigations simultaneously. Using a variant of the Friis transmission equation, emissions data is used to estimate and plot the emitter’s locations over time for comparison with current flights. The data is also displayed on a set of five linked graphs to aid in the perception of patterns spanning power, time, frequency, and bearing. Based on details of the signal (its classification, direction, and strength, etc.), TRACER retrieves one or more cases of EMI investigation methodologies which are represented as graphical behavior transition networks (BTNs). These BTNs can be edited easily

  5. Conical square function estimates in UMD Banach spaces and applications to H?-functional calculi

    NARCIS (Netherlands)

    Hytönen, T.; Van Neerven, J.; Portal, P.

    2008-01-01

    We study conical square function estimates for Banach-valued functions and introduce a vector-valued analogue of the Coifman-Meyer-Stein tent spaces. Following recent work of Auscher-M(c)Intosh-Russ, the tent spaces in turn are used to construct a scale of vector-valued Hardy spaces associated with

  6. Chemical evolution of Titan’s aerosol analogues under VUV irradiation

    Science.gov (United States)

    Carrasco, Nathalie; Gavilan, Lisseth; Tigrine, Sarah; Vettier, Ludovic; Nahon, Laurent; Pernot, Pascal

    2017-10-01

    Since the Cassini-CAPS measurements, organic aerosols are known to be present and formed at high altitudes in the diluted and partially ionized medium that is Titan’s ionosphere [1].After production in the ionosphere, Titan’s aerosols evolve through microphysics during their sedimentation down to Titan’s surface [2]. Starting with a few nanomers size in the upper atmosphere, they reach a fractal structure of a few hundreds nanometers close to the surface [3]. During sedimentation, aerosols are also submitted to solar irradiation. As laboratory analogs of Titan’s atmospheric aerosols (tholins) show a strong UV absorption [4], we suspect that VUV irradiation could also induce a chemical evolution of Titan’s aerosols during their descent in Titan’s atmosphere.The aim of this work ist to simulate the irradiation process occuring on the aerosols in Titan’s atmosphere and to address whether this irradiation impacts the chemical composition of the organic solids. First aerosol analogues were produced in a N2-CH4 plasma discharge as thin organic films of a few hundreds of nanometers thick [5]. Then those were irradiated at Lyman-α wavelength, the strongest VUV line in the solar spectrum, with a high photon flux on a synchrotron VUV beamline. We will present and discuss the significant chemical evolutions observed on the analogues after VUV irradiation by mid-IR absorption spectroscopy.[1] Waite et al. (2009) Science , 316, p. 870[2] Lavvas et al. (2011) Astrophysical Journal, 728:80[3] Tomasko et al. (2008) Planetary and Space Science, 56, p. 669[4] Mahjoub et al. (2012) Icarus 221, P. 670[5] Carrasco et al. (2016) Planetary and Space Science, 128, p. 52

  7. Phosphorylation of inositol 1,4,5-trisphosphate analogues by 3-kinase and dephosphorylation of inositol 1,3,4,5-tetrakisphosphate analogues by 5-phosphatase

    NARCIS (Netherlands)

    Dijken, Peter van; Lammers, Aleida A.; Ozaki, Shoichiro; Potter, Barry V.L.; Erneux, Christophe; Haastert, Peter J.M. van

    1994-01-01

    A series of P-32-labeled D-myo-inositol 1,3,4,5-tetrakisphosphate [Ins(1,3,4,5)P-4] analogues was enzymically prepared from the corresponding D-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P-3] analogues using recombinant rat brain Ins(1,4,5)P-3 3-kinase and [gamma-P-32]ATP. Ins(1,4,5)P-3 analogues

  8. The Greenland Analogue Project. Yearly Report 2010

    International Nuclear Information System (INIS)

    Harper, J.; Hubbard, A.; Ruskeeniemi, T.

    2011-12-01

    Sub-project A, (SPA), Ice sheet hydrology and subglacial groundwater formation. SPA aims to improve the understanding of ice sheet hydrology (i.e. to assess how an ice sheet impacts groundwater circulation and chemistry in crystalline bedrock) up to, including, and beyond proposed repository depths. The data collected in SPA will be utilized in numerical ice sheet flow and hydrological modelling. SPA focuses on indirect observations of the properties of the basal hydrological system, and on what parts of the ice sheet that contribute water for groundwater infiltration. The latter includes quantification of ice sheet surface water production and how that water is routed from the ice sheet surface to its basal interface. This is achieved through remote-sensing, as well as direct measurements of vertical ice displacement and horizontal velocity fluctuation, and the determination of how these parameters vary in space and time under variable surface meltwater production and routing. Main activities within SPA involve (1) the installation and monitoring of GPS receivers and automatic weather stations on the ice sheet, and (2) air borne- and ground-based radar studies. Sub-project B, (SPB), Subglacial ice sheet hydrology. SPB, like SPA, aims at improving the understanding of ice sheet hydrology. SPB aims at collecting direct observations and measurements of the characteristics of the hydrological system at the base of the ice sheet. The data collected in SPB will be utilized in numerical ice sheet flow and hydrological modelling. The main activity for SPB is drilling through the ice sheet at a number of locations where the ice sheet has been found to be wet-based from the radar surveys in SPA. The purpose of the drilling and borehole monitoring installations is to observe water pressures at the interface between the ice and bedrock. In addition to the ice drilling, collection of remote sensing data of ice-sheet surface conditions are to be carried out. SPB is the core of

  9. The Greenland Analogue Project. Yearly Report 2010

    Energy Technology Data Exchange (ETDEWEB)

    Harper, J. (Univ. of Montana (United States)); Hubbard, A. (Aberystwyth Univ. (United Kingdom)); Ruskeeniemi, T. (Geological Survey of Finland (Finland)) (and others)

    2011-12-15

    Sub-project A, (SPA), Ice sheet hydrology and subglacial groundwater formation. SPA aims to improve the understanding of ice sheet hydrology (i.e. to assess how an ice sheet impacts groundwater circulation and chemistry in crystalline bedrock) up to, including, and beyond proposed repository depths. The data collected in SPA will be utilized in numerical ice sheet flow and hydrological modelling. SPA focuses on indirect observations of the properties of the basal hydrological system, and on what parts of the ice sheet that contribute water for groundwater infiltration. The latter includes quantification of ice sheet surface water production and how that water is routed from the ice sheet surface to its basal interface. This is achieved through remote-sensing, as well as direct measurements of vertical ice displacement and horizontal velocity fluctuation, and the determination of how these parameters vary in space and time under variable surface meltwater production and routing. Main activities within SPA involve (1) the installation and monitoring of GPS receivers and automatic weather stations on the ice sheet, and (2) air borne- and ground-based radar studies. Sub-project B, (SPB), Subglacial ice sheet hydrology. SPB, like SPA, aims at improving the understanding of ice sheet hydrology. SPB aims at collecting direct observations and measurements of the characteristics of the hydrological system at the base of the ice sheet. The data collected in SPB will be utilized in numerical ice sheet flow and hydrological modelling. The main activity for SPB is drilling through the ice sheet at a number of locations where the ice sheet has been found to be wet-based from the radar surveys in SPA. The purpose of the drilling and borehole monitoring installations is to observe water pressures at the interface between the ice and bedrock. In addition to the ice drilling, collection of remote sensing data of ice-sheet surface conditions are to be carried out. SPB is the core of

  10. The analogue method for precipitation prediction: finding better analogue situations at a sub-daily time step

    Science.gov (United States)

    Horton, Pascal; Obled, Charles; Jaboyedoff, Michel

    2017-07-01

    Analogue methods (AMs) predict local weather variables (predictands) such as precipitation by means of a statistical relationship with predictors at a synoptic scale. The analogy is generally assessed on gradients of geopotential heights first to sample days with a similar atmospheric circulation. Other predictors such as moisture variables can also be added in a successive level of analogy. The search for candidate situations similar to a given target day is usually undertaken by comparing the state of the atmosphere at fixed hours of the day for both the target day and the candidate analogues. This is a consequence of using standard daily precipitation time series, which are available over longer periods than sub-daily data. However, it is unlikely for the best analogy to occur at the exact same hour for the target and candidate situations. A better analogue situation may be found with a time shift of several hours since a better fit can occur at different times of the day. In order to assess the potential for finding better analogues at a different hour, a moving time window (MTW) has been introduced. The MTW resulted in a better analogy in terms of the atmospheric circulation and showed improved values of the analogy criterion on the entire distribution of the extracted analogue dates. The improvement was found to increase with the analogue rank due to an accumulation of better analogues in the selection. A seasonal effect has also been identified, with larger improvements shown in winter than in summer. This may be attributed to stronger diurnal cycles in summer that favour predictors taken at the same hour for the target and analogue days. The impact of the MTW on the precipitation prediction skill has been assessed by means of a sub-daily precipitation series transformed into moving 24 h totals at 12, 6, and 3 h time steps. The prediction skill was improved by the MTW, as was the reliability of the prediction. Moreover, the improvements were greater for days

  11. Optical gyrotropy from axion electrodynamics in momentum space

    OpenAIRE

    Zhong, Shudan; Orenstein, Joseph; Moore, Joel E.

    2015-01-01

    Several emergent phenomena and phases in solids arise from configurations of the electronic Berry phase in momentum space that are similar to gauge field configurations in real space such as magnetic monopoles. We show that the momentum-space analogue of the "axion electrodynamics" term $\\mathbf{E}\\cdot\\mathbf{B}$ plays a fundamental role in a unified theory of Berry-phase contributions to optical gyrotropy in time-reversal invariant materials and the chiral magnetic effect. The Berry-phase m...

  12. AdS and dS black hole solutions in analogue gravity: The relativistic and non-relativistic cases

    OpenAIRE

    Dey, Ramit; Liberati, Stefano; Turcati, Rodrigo

    2016-01-01

    We show that Schwarzschild black hole solutions in asymptotically Anti-de Sitter (AdS) and de Sitter (dS) spaces may, up to a conformal factor, be reproduced in the framework of analogue gravity. The aforementioned derivation is performed using relativistic and non-relativistic Bose-Einstein condensates. In addition, we demonstrate that the (2+1) planar AdS black hole can be mapped into the non-relativistic acoustic metric. Given that AdS black holes are extensively employed in the gauge/grav...

  13. Teppeki, selective insecticide about Bombus terrestris.

    Science.gov (United States)

    Fanigliulo, Angela; Filì, Vittorio; Pacella, Rosa; Comes, Soccorsa; Crescenzi, Aniello

    2009-01-01

    At a time when a highly controversial debate about the causes of the widespread deaths of bees is taking place all over Europe, which accused the agriculture and its practices with particular reference to the harmful effects of some insecticides, it seems important to point out as another insecticide, the Teppeki, can be selective about bumble and have a good compatibility with the activity of the apiaries. This insecticide has the active ingredient flonicamid (500 g/kg) belonging to a new chemical class, called pyridinecarboxamides: the product works systemic and is known as having a long lasting efficacy against all important aphid species. Bioagritest test facility of Pignola (PZ, Italy) has conducted in two successive production cycles an experimental trial on a tomato hydroponic cultivation within the Agricola Bonsai farm in Sibari (CS, Italy), whose objective was to measure the selectivity of flonicamid on Bombus terrestris, insects playing an important role in the pollination of certain species grown in greenhouse such as Tomato, Eggplant, Pepper and Cucumber. On the pollinated flower B. terrestris leaves some trace of its visit, a typical dark trademark: on the detection of the marking of flowers was based the testing program conducted by Bioagritest. Two thesis were compared: A, standard) treatment with a foliar insecticide, the neonicotinoide acetamiprid, normally used for control of aphids and whiteflies (unlike other neonicotinoides--imidacloprid and thiametoxam--quite selective about B. terrestris) and B, Teppeki) foliar treatment with Teppeki, to the maximum dose indicated on the label. The experimental design included the use of randomized blocks with 4 repetitions (4 plots/thesis with 100 plants each). In every thesis six B. terrestris hives were placed 2 days before treatment: the respective holes remained closed during the treatment and the 12 following hours. In order to verify the pollination, by the detection of the flower marking, 2 flowers

  14. Optoelectronic analogue signal transfer for LHC detectors, 1991

    CERN Document Server

    Dowell, John D; Homer, R J; Jovanovic, P; Kenyon, I; Staley, R; Webster, K; Da Via, C; Feyt, J; Nappey, P; Stefanini, G; Dwir, B; Reinhart, F K; Davies, J; Green, N; Stewart, W; Young, T; Hall, G; Akesson, T; Jarlskog, G; Kröll, S; Nickerson, R; Jaroslawski, S; CERN. Geneva. Detector Research and Development Committee

    1991-01-01

    We propose to study and develop opto-electronic analogue front-ends based on electro-optic intensity modulators. These devices translate the detector electrical analogue signals into optical signals which are then transferred via optical fibres to photodetector receivers at the remote readout. In comparison with conventional solutions based on copper cables, this technique offers the advantages of high speed, very low power dissipation and transmission losses, compactness and immunity to electromagnetic interference. The linearity and dynamic range that can be obtained are more than adequate for central tracking detectors, and the proposed devices have considerable radiation- hardness capabilities. The large bandwidth and short transit times offer possibilities for improved triggering schemes. The proposed R&D programme is aimed at producing multi-channel "demonstrator" units for evaluation both in laboratory and beam tests. This will allow the choice of the most effective technology. A detailed study wil...

  15. Ribosome-catalyzed formation of an abnormal peptide analogue

    International Nuclear Information System (INIS)

    Roesser, J.R.; Chorghade, M.S.; Hecht, S.M.

    1986-01-01

    The peptidyl-tRNA analogue N-(chloracetyl) phenylalanyl-tRNA/sup Phe/ was prepared by chemical aminoacylation and prebound to the P site of Escherichia coli ribosomes in response to poly(uridylic acid). Admixture of phenylalanyl-tRNA/sup Phe/ to the A site resulted in the formation of two dipeptides, one of which was found by displacement of chloride ion from the peptidyl-tRNA. This constitutes the first example of ribosome-mediated formation of a peptide of altered connectivity and suggests a need for revision of the current model of peptide bond formation. Also suggested by the present finding is the feasibility of utilizing tRNAs to prepare polypeptides of altered connectivity in an in vitro protein biosynthesizing system. [ 32 P]-oligo(rA), [ 3 H]- and [ 14 C] phenylalanines were used in the assay of the peptidye-tRNA analogue

  16. Concentration and second-gas effects in the water analogue.

    Science.gov (United States)

    Mapleson, W W; Korman, B

    1998-12-01

    The water analogue provides a visual model of the process of anaesthetic exchange. In the standard version, a single pipe connects the mouth container to the lung container and the conductance of this mouth-lung pipe is proportional to alveolar ventilation. This implies that inspired and expired ventilations are equal. In fact, with high inspired concentrations of nitrous oxide, early rapid uptake of gas by solution leads to a substantial difference between inspired and expired ventilation which in turn leads to concentration and second-gas effects. It is shown that by representing inspired and expired ventilations separately, and keeping one of them constant while varying the other to compensate for rapid uptake, concentration and second-gas effects are reproduced in the water analogue. Other means of reproducing the effects are reported but we believe that the first method is the most realistic and the most appropriate for teaching.

  17. A rationally designed CD4 analogue inhibits experimental allergic encephalomyelitis

    Science.gov (United States)

    Jameson, Bradford A.; McDonnell, James M.; Marini, Joseph C.; Korngold, Robert

    1994-04-01

    EXPERIMENTAL allergic encephalomyelitis (EAE) is an acute inflammatory autoimmune disease of the central nervous system that can be elicited in rodents and is the major animal model for the study of multiple sclerosis (MS)1,2. The pathogenesis of both EAE and MS directly involves the CD4+ helper T-cell subset3-5. Anti-CD4 monoclonal antibodies inhibit the development of EAE in rodents6-9, and are currently being used in human clinical trials for MS. We report here that similar therapeutic effects can be achieved in mice using a small (rationally designed) synthetic analogue of the CD4 protein surface. It greatly inhibits both clinical incidence and severity of EAE with a single injection, but does so without depletion of the CD4+ subset and without the inherent immunogenicity of an antibody. Furthermore, this analogue is capable of exerting its effects on disease even after the onset of symptoms.

  18. Optical analogue of relativistic Dirac solitons in binary waveguide arrays

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Truong X., E-mail: truong.tran@mpl.mpg.de [Department of Physics, Le Quy Don University, 236 Hoang Quoc Viet str., 10000 Hanoi (Viet Nam); Max Planck Institute for the Science of Light, Günther-Scharowsky str. 1, 91058 Erlangen (Germany); Longhi, Stefano [Department of Physics, Politecnico di Milano and Istituto di Fotonica e Nanotecnologie del Consiglio Nazionale delle Ricerche, Piazza L. da Vinci 32, I-20133 Milano (Italy); Biancalana, Fabio [Max Planck Institute for the Science of Light, Günther-Scharowsky str. 1, 91058 Erlangen (Germany); School of Engineering and Physical Sciences, Heriot-Watt University, EH14 4AS Edinburgh (United Kingdom)

    2014-01-15

    We study analytically and numerically an optical analogue of Dirac solitons in binary waveguide arrays in the presence of Kerr nonlinearity. Pseudo-relativistic soliton solutions of the coupled-mode equations describing dynamics in the array are analytically derived. We demonstrate that with the found soliton solutions, the coupled mode equations can be converted into the nonlinear relativistic 1D Dirac equation. This paves the way for using binary waveguide arrays as a classical simulator of quantum nonlinear effects arising from the Dirac equation, something that is thought to be impossible to achieve in conventional (i.e. linear) quantum field theory. -- Highlights: •An optical analogue of Dirac solitons in nonlinear binary waveguide arrays is suggested. •Analytical solutions to pseudo-relativistic solitons are presented. •A correspondence of optical coupled-mode equations with the nonlinear relativistic Dirac equation is established.

  19. Somatostatin analogues labelled with 99mTc

    International Nuclear Information System (INIS)

    Obenaus, Esteban R.; Crudo, Jose L.; Edreira, Martin M.; Castiglia, Silvia G.

    1999-01-01

    Biological and radiochemical studies have been carried out on two labelled somatostatin analogues, the peptide RC-150 and the Tyr 3 -Octreotide. Both analogues have been labelled with 99m Tc using the direct and the indirect method and MAG-3 and HYNIC as chelating agents. By the direct method RC-150 was labelled using sodium ascorbate and dithionite as reducing agents. The radiochemical purity was 70%. By the indirect method, in the case of RC-160 with MAG-3 a radiochemical purity higher than 70% was attained while a purity of 100% was reached in the case of Tyr 3 -Octreotide with HYNIC. The biological distribution of HYNIC-Tyr 3 -Octreotide has been studied in rats. (author)

  20. Anti-cancer activities of diospyrin, its derivatives and analogues

    KAUST Repository

    Sagar, Sunil

    2010-09-01

    Natural products have played a vital role in drug discovery and development process for cancer. Diospyrin, a plant based bisnaphthoquinonoid, has been used as a lead molecule in an effort to develop anti-cancer drugs. Several derivatives/analogues have been synthesized and screened for their pro-apoptotic/anti-cancer activities so far. Our review is focused on the pro-apoptotic/anti-cancer activities of diospyrin, its derivatives/analogues and the different mechanisms potentially involved in the bioactivity of these compounds. Particular focus has been placed on the different mechanisms (both chemical and molecular) thought to underlie the bioactivity of these compounds. A brief bioinformatics analysis at the end of the article provides novel insights into the new potential mechanisms and pathways by which these compounds might exert their effects and lead to a better realization of the full therapeutic potential of these compounds as anti-cancer drugs. © 2010 Elsevier Masson SAS. All rights reserved.

  1. Solid-phase synthesis of polyamine toxin analogues

    DEFF Research Database (Denmark)

    Kromann, Hasse; Krikstolaityte, Sonata; Andersen, Anne J

    2002-01-01

    The wasp toxin philanthotoxin-433 (PhTX-433) is a nonselective and noncompetitive antagonist of ionotropic receptors, such as ionotropic glutamate receptors and nicotinic acetylcholine receptors. Polyamine toxins are extensively used for the characterization of subtypes of ionotropic glutamate...... receptors, in particular Ca(2+)-permeable AMPA and kainate receptors. We have previously shown that an analogue of PhTX-433 with one of the amino groups replaced by a methylene group, philanthotoxin-83 (PhTX-83) is a selective and potent antagonist of AMPA receptors. We now describe the solid...... of analogues, the acyl moiety of PhTX-83 was replaced by acids of different size and lipophilicity. Using electrophysiological techniques, PhTX-56 was shown to be a highly potent (K(i) = 3.3 +/- 0.78 nM) and voltage-dependent antagonist of homomeric GluR1 receptors and was more than 1000-fold less potent when...

  2. New Immunosuppressive Sphingoid Base and Ceramide Analogues in Wild Cordyceps

    Science.gov (United States)

    Mi, Jia-Ning; Han, Yuwei; Xu, Yingqiong; Kou, Junping; Wang, Jing-Rong; Jiang, Zhi-Hong

    2016-01-01

    A comprehensive identification of sphingoid bases and ceramides in wild Cordyceps was performed by integrating a sequential chromatographic enrichment procedure and an UHPLC-ultrahigh definition-Q-TOF-MS based sphingolipidomic approach. A total of 43 sphingoid bases and 303 ceramides were identified from wild Cordyceps, including 12 new sphingoid base analogues and 159 new ceramide analogues based on high-resolution MS and MS/MS data, isotope distribution, matching with the comprehensive personal sphingolipid database, confirmation by sphingolipid standards and chromatographic retention time rule. The immunosuppressive bioassay results demonstrated that Cordyceps sphingoid base fraction exhibits more potent immunosuppressive activity than ceramide fraction, elucidating the immunosuppressive ingredients of wild Cordyceps. This study represented the most comprehensive identification of sphingoid bases and ceramides from a natural source. The findings of this study provided an insight into therapeutic application of wild Cordyceps. PMID:27966660

  3. Haplopappus gracilis cell strains resistant to pyrimidine analogues.

    Science.gov (United States)

    Jones, G E; Hann, J

    1979-03-01

    Strains of Haplopappus gracilis (Nutt.) Gray cells resistant to 6-azauracil have been isolated from cultures of diploid cells. These strains are also resistant to 8-azaguanine, as is their parent. The variants are 100- to 125-fold more resistant to 6-azauracil than their parent, and they exhibit different spectra of cross resistance to other pyrimidine analogues. The phenotype of each variant is stable in the absence of selection. The majority of cells in cultures of the variants are diploid; all others examined were tetraploid. Initial rates of uptake of uracil are not reduced in the variants. Fluorouracil, to which two variants are resistant, is taken up by one of them as well as by the parent. Responses of the other two to fluorouracil are not correlated with decreased ability to accumulate this analogue.

  4. Higher-dimensional analogues of Donaldson-Witten theory

    International Nuclear Information System (INIS)

    Acharya, B.S.; Spence, B.

    1997-01-01

    We present a Donaldson-Witten-type field theory in eight dimensions on manifolds with Spin(7) holonomy. We prove that the stress tensor is BRST exact for metric variations preserving the holonomy and we give the invariants for this class of variations. In six and seven dimensions we propose similar theories on Calabi-Yau threefolds and manifolds of G 2 holonomy, respectively. We point out that these theories arise by considering supersymmetric Yang-Mills theory defined on such manifolds. The theories are invariant under metric variations preserving the holonomy structure without the need for twisting. This statement is a higher-dimensional analogue of the fact that Donaldson-Witten field theory on hyper-Kaehler 4-manifolds is topological without twisting. Higher-dimensional analogues of Floer cohomology are briefly outlined. All of these theories arise naturally within the context of string theory. (orig.)

  5. Evolution of ore deposits on terrestrial planets

    Science.gov (United States)

    Burns, R. G.

    1991-01-01

    Ore deposits on terrestrial planets materialized after core formation, mantle evolution, crustal development, interactions of surface rocks with the hydrosphere and atmosphere, and, where life exists on a planet, the involvement of biological activity. Core formation removed most of the siderophilic and chalcophilic elements, leaving mantles depleted in many of the strategic and noble metals relative to their chondritic abundances. Basaltic magma derived from partial melting of the mantle transported to the surface several metals contained in immiscible silicate and sulfide melts. Magmatic ore deposits were formed during cooling, fractional crystallization and density stratification from the basaltic melts. Such ore deposits found in earth's Archean rocks were probably generated during early histories of all terrestrial planets and may be the only types of igneous ores on Mars. Where plate tectonic activity was prevalent on a terrestrial planet, temporal evolution of ore deposits took place. Repetitive episodes of subduction modified the chemical compositions of the crust and upper mantles, leading to porphyry copper and molybdenum ores in calc-alkaline igneous rocks and granite-hosted tin and tungsten deposits. Such plate tectonic-induced mineralization in relatively young igneous rocks on earth may also have produced hydrothermal ore deposits on Venus in addition to the massive sulfide and cumulate chromite ores associated with Venusian mafic igneous rock. Sedimentary ore deposits resulting from mechanical and chemical weathering in reducing atmospheres in Archean earth included placer deposits (e.g., uraninite, gold, pyrite ores). Chromite, ilmenite, and other dense unreactive minerals could also be present on channel floors and in valley networks on Mars, while banded iron formations might underlie the Martian northern plains regions. As oxygen evolved in earth's atmosphere, so too did oxide ores. By analogy, gossans above sulfide ores probably occur on Mars

  6. Localisation and mechanism of renal retention of radiolabelled somatostatin analogues

    Energy Technology Data Exchange (ETDEWEB)

    Melis, Marleen; Krenning, Eric P.; Bernard, Bert F.; Jong, Marion de [Erasmus MC, Department of Nuclear Medicine, Rotterdam (Netherlands); Barone, Raffaella [UCL, Centre of Nuclear Medicine and Laboratory of PET, Brussels (Belgium); Visser, Theo J. [Erasmus MC, Department of Internal Medicine, Rotterdam (Netherlands)

    2005-10-01

    Radiolabelled somatostatin analogues, such as octreotide and octreotate, are used for tumour scintigraphy and radionuclide therapy. The kidney is the most important critical organ during such therapy owing to the reabsorption and retention of radiolabelled peptides. The aim of this study was to investigate in a rat model both the localisation and the mechanism of renal uptake after intravenous injection of radiolabelled somatostatin analogues. The multi-ligand megalin/cubilin receptor complex, responsible for reabsorption of many peptides and proteins in the kidney, is an interesting candidate for renal endocytosis of these peptide analogues. For localisation studies, ex vivo autoradiography and micro-autoradiography of rat kidneys were performed 1-24 h after injection of radiolabelled somatostatin analogues and compared with the renal anti-megalin immunohistochemical staining pattern. To confirm a role of megalin in the mechanism of renal retention of [{sup 111}In-DTPA]octreotide, the effects of three inhibitory substances were explored in rats. Renal ex vivo autoradiography showed high cortical radioactivity and lower radioactivity in the outer medulla. The distribution of cortical radioactivity was inhomogeneous. Micro-autoradiography indicated that radioactivity was only retained in the proximal tubules. The anti-megalin immunohistochemical staining pattern showed a strong similarity with the renal [{sup 111}In-DTPA]octreotide ex vivo autoradiograms. Biodistribution studies showed that co-injection of positively charged d-lysine reduced renal uptake to 60% of control. Sodium maleate reduced renal [{sup 111}In-DTPA]octreotide uptake to 15% of control. Finally, cisplatin pre-treatment of rats reduced kidney uptake to 70% of control. Renal retention of [{sup 111}In-DTPA]octreotide is confined to proximal tubules in the rat kidney, in which megalin-mediated endocytosis may play an important part. (orig.)

  7. Rubrene analogues with the aggregation-induced emission enhancement behaviour

    DEFF Research Database (Denmark)

    Zhang, Xiaoxu; Sørensen, Jakob Kryger; Fu, Xiaowei

    2014-01-01

    In the light of the principle of aggregation-induced emission enhancement (AIEE), the rubrene analogue with orange light-emitting properties is designed and synthesized by substituting the phenyl side groups of rubrene with thienyl groups. To the best of our knowledge, this is the first report on...... on the synthesis of rubrene with AIEE behaviour, thus paving the way for the development of light-emitting rubrene derivatives. This journal is...

  8. Synthetic analogues of natural semiochemicals as promising insect control agents

    International Nuclear Information System (INIS)

    Ujvary, Istvan; Toth, Miklos; Guerin, Patrick

    2000-01-01

    After decades of research and development, insect pheromones and other semiochemicals became indispensable tools of ecologically based agricultural pest and disease vector management programmes with main uses as: 1) detection and population monitoring of emerging and migrating insects, 2) mass trapping of insects, 3) combined formulation of semiochemicals and insecticides ('lure-and-kill'), and 4) mating disruption with specially formulated pheromone components. In spite of their demonstrated safety and biodegradability, the direct application of these semiochemicals for pest control has not fulfilled initial expectations. Nonetheless considerable field experience has been accumulated (Carde and Minks 1995). Evidently, two important factors limit the practical potential of these substances: 1) inherent in their particular mode of action, semiochemicals, especially pheromones, are effectively cleared by specific enzymes in the insect antennae, and 2) some of these compounds contain labile functional moieties that are prone to degradation (oxidation, isomerisation and polymerisation) under field conditions. Appropriate chemical modifications of these natural compounds, however, can circumvent these problems by providing synthetic analogues (sometimes also called parapheromones or antipheromones; for early studies, see Roelofs and Comeau 1971, Payne et al. 1973) which in ideal cases are not only more potent and environmentally acceptable but more economical as well. It should also be mentioned that many effective attractants have been discovered through the empirical screening of synthetic chemicals, some of which have actually turned out to be structural relatives of natural semiochemicals of the particular insect. In this paper, selected case studies of analogues of sex pheromones and kairomones will be presented. The examples from our work include nitrile bioisosteres of labile aldehyde pheromone components of the cranberry girdler moth, Chrysoteuchia topiaria

  9. Evaluation of Anti-HIV-1 Mutagenic Nucleoside Analogues*

    Science.gov (United States)

    Vivet-Boudou, Valérie; Isel, Catherine; El Safadi, Yazan; Smyth, Redmond P.; Laumond, Géraldine; Moog, Christiane; Paillart, Jean-Christophe; Marquet, Roland

    2015-01-01

    Because of their high mutation rates, RNA viruses and retroviruses replicate close to the threshold of viability. Their existence as quasi-species has pioneered the concept of “lethal mutagenesis” that prompted us to synthesize pyrimidine nucleoside analogues with antiviral activity in cell culture consistent with an accumulation of deleterious mutations in the HIV-1 genome. However, testing all potentially mutagenic compounds in cell-based assays is tedious and costly. Here, we describe two simple in vitro biophysical/biochemical assays that allow prediction of the mutagenic potential of deoxyribonucleoside analogues. The first assay compares the thermal stabilities of matched and mismatched base pairs in DNA duplexes containing or not the nucleoside analogues as follows. A promising candidate should display a small destabilization of the matched base pair compared with the natural nucleoside and the smallest gap possible between the stabilities of the matched and mismatched base pairs. From this assay, we predicted that two of our compounds, 5-hydroxymethyl-2′-deoxyuridine and 5-hydroxymethyl-2′-deoxycytidine, should be mutagenic. The second in vitro reverse transcription assay assesses DNA synthesis opposite nucleoside analogues inserted into a template strand and subsequent extension of the newly synthesized base pairs. Once again, only 5-hydroxymethyl-2′-deoxyuridine and 5-hydroxymethyl-2′-deoxycytidine are predicted to be efficient mutagens. The predictive potential of our fast and easy first line screens was confirmed by detailed analysis of the mutation spectrum induced by the compounds in cell culture because only compounds 5-hydroxymethyl-2′-deoxyuridine and 5-hydroxymethyl-2′-deoxycytidine were found to increase the mutation frequency by 3.1- and 3.4-fold, respectively. PMID:25398876

  10. Evaluation of anti-HIV-1 mutagenic nucleoside analogues.

    Science.gov (United States)

    Vivet-Boudou, Valérie; Isel, Catherine; El Safadi, Yazan; Smyth, Redmond P; Laumond, Géraldine; Moog, Christiane; Paillart, Jean-Christophe; Marquet, Roland

    2015-01-02

    Because of their high mutation rates, RNA viruses and retroviruses replicate close to the threshold of viability. Their existence as quasi-species has pioneered the concept of "lethal mutagenesis" that prompted us to synthesize pyrimidine nucleoside analogues with antiviral activity in cell culture consistent with an accumulation of deleterious mutations in the HIV-1 genome. However, testing all potentially mutagenic compounds in cell-based assays is tedious and costly. Here, we describe two simple in vitro biophysical/biochemical assays that allow prediction of the mutagenic potential of deoxyribonucleoside analogues. The first assay compares the thermal stabilities of matched and mismatched base pairs in DNA duplexes containing or not the nucleoside analogues as follows. A promising candidate should display a small destabilization of the matched base pair compared with the natural nucleoside and the smallest gap possible between the stabilities of the matched and mismatched base pairs. From this assay, we predicted that two of our compounds, 5-hydroxymethyl-2'-deoxyuridine and 5-hydroxymethyl-2'-deoxycytidine, should be mutagenic. The second in vitro reverse transcription assay assesses DNA synthesis opposite nucleoside analogues inserted into a template strand and subsequent extension of the newly synthesized base pairs. Once again, only 5-hydroxymethyl-2'-deoxyuridine and 5-hydroxymethyl-2'-deoxycytidine are predicted to be efficient mutagens. The predictive potential of our fast and easy first line screens was confirmed by detailed analysis of the mutation spectrum induced by the compounds in cell culture because only compounds 5-hydroxymethyl-2'-deoxyuridine and 5-hydroxymethyl-2'-deoxycytidine were found to increase the mutation frequency by 3.1- and 3.4-fold, respectively. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. The Two-Dimensional Analogue of General Relativity

    OpenAIRE

    Lemos, José P. S.; Sá, Paulo M.

    1993-01-01

    General Relativity in three or more dimensions can be obtained by taking the limit $\\omega\\rightarrow\\infty$ in the Brans-Dicke theory. In two dimensions General Relativity is an unacceptable theory. We show that the two-dimensional closest analogue of General Relativity is a theory that also arises in the limit $\\omega\\rightarrow\\infty$ of the two-dimensional Brans-Dicke theory.

  12. Matrix diffusion model. In situ tests using natural analogues

    International Nuclear Information System (INIS)

    Rasilainen, K.

    1997-11-01

    Matrix diffusion is an important retarding and dispersing mechanism for substances carried by groundwater in fractured bedrock. Natural analogues provide, unlike laboratory or field experiments, a possibility to test the model of matrix diffusion in situ over long periods of time. This thesis documents quantitative model tests against in situ observations, done to support modelling of matrix diffusion in performance assessments of nuclear waste repositories

  13. Matrix diffusion model. In situ tests using natural analogues

    Energy Technology Data Exchange (ETDEWEB)

    Rasilainen, K. [VTT Energy, Espoo (Finland)

    1997-11-01

    Matrix diffusion is an important retarding and dispersing mechanism for substances carried by groundwater in fractured bedrock. Natural analogues provide, unlike laboratory or field experiments, a possibility to test the model of matrix diffusion in situ over long periods of time. This thesis documents quantitative model tests against in situ observations, done to support modelling of matrix diffusion in performance assessments of nuclear waste repositories. 98 refs. The thesis includes also eight previous publications by author.

  14. (18)F-labelled metomidate analogues as adrenocortical imaging agents.

    Science.gov (United States)

    Erlandsson, Maria; Karimi, Farhad; Lindhe, Orjan; Långström, Bengt

    2009-05-01

    Two- and one-step syntheses of (18)F-labelled analogues of metomidate, such as 2-[(18)F]fluoroethyl 1-[(1R)-1-phenylethyl]-1H-imidazole-5-carboxylate (1), 2-[(18)F]fluoroethyl 1-[(1R)-1-(4-chlorophenyl)ethyl]-1H-imidazole-5-carboxylate (2), 2-[(18)F]fluoroethyl 1-[(1R)-1-(4-bromophenyl)ethyl]-1H-imidazole-5-carboxylate (3), 3-[(18)F]fluoropropyl 1-[(1R)-1-(4-bromophenyl)ethyl]-1H-imidazole-5-carboxylate (4) and 3-[(18)F]fluoropropyl 1-[(1R)-1-phenylethyl]-1H-imidazole-5-carboxylate (5) are presented. Analogues 1-5 were prepared by a two-step reaction sequence that started with the synthesis of either 2-[(18)F]fluoroethyl 4-methylbenzenesulfonate or 3-[(18)F]fluoropropyl 4-methylbenzenesulfonate. These were used as (18)F-alkylating agents in the second step, in which they reacted with the ammonium salt of a 1-[(1R)-1-phenylethyl]-1H-imidazole-5-carboxylic acid. One-step-labelling syntheses of 1, 2 and 5 were also explored. Analogues 1-4 were biologically validated by frozen-section autoradiography and organ distribution. Metabolite analysis was performed for 2 and 3. The radiochemical yield of the two-step synthesis was in the range of 10-29% and that of the one-step synthesis was 25-37%. Using microwave irradiation in the one-step synthesis of 1 and 2 increased the radiochemical yield to 46+/-3% and 79+/-30%, respectively. Both the frozen-section autoradiography and organ distribution results indicated that analogue 2 has a potential as an adrenocortical imaging agent, having the highest degree of specific adrenal binding and best ratio of adrenal to organ uptake among the compounds studied.

  15. Kidney protection during peptide receptor radionuclide therapy with somatostatin analogues

    Energy Technology Data Exchange (ETDEWEB)

    Rolleman, Edgar J.; Melis, Marleen; Valkema, Roelf; Krenning, Eric P.; Jong, Marion de [Erasmus MC, Department of Nuclear Medicine, V 220, Rotterdam (Netherlands); Boerman, Otto C. [Radboud University Hospital, Department of Nuclear Medicine, Nijmegen (Netherlands)

    2010-05-15

    This review focuses on the present status of kidney protection during peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues. This treatment modality for somatostatin receptor-positive tumours is limited by renal reabsorption and retention of radiolabelled peptides resulting in dose-limiting high kidney radiation doses. Radiation nephropathy has been described in several patients. Studies on the mechanism and localization demonstrate that renal uptake of radiolabelled somatostatin analogues largely depends on the megalin/cubulin system in the proximal tubule cells. Thus methods are needed that interfere with this reabsorption pathway to achieve kidney protection. Such methods include coadministration of basic amino acids, the bovine gelatin-containing solution Gelofusine or albumin fragments. Amino acids are already commonly used in the clinical setting during PRRT. Other compounds that interfere with renal reabsorption capacity (maleic acid and colchicine) are not suitable for clinical use because of potential toxicity. The safe limit for the renal radiation dose during PRRT is not exactly known. Dosimetry studies applying the principle of the biological equivalent dose (correcting for the effect of dose fractionation) suggest that a dose of about 37 Gy is the threshold for development of kidney toxicity. This threshold is lower when risk factors for development of renal damage exist: age over 60 years, hypertension, diabetes mellitus and previous chemotherapy. A still experimental pathway for kidney protection is mitigation of radiation effects, possibly achievable by cotreatment with amifostine (Ethylol), a radiation protector, or with blockers of the renin-angiotensin-aldosterone system. Future perspectives on improving kidney protection during PRRT include combinations of agents to reduce renal retention of radiolabelled peptides, eventually together with mitigating medicines. Moreover, new somatostatin analogues with lower

  16. Combinatorial Solid-Phase Synthesis of Balanol Analogues

    DEFF Research Database (Denmark)

    Nielsen, John; Lyngsø, Lars Ole

    1996-01-01

    The natural product balanol has served as a template for the design and synthesis of a combinatorial library using solid-phase chemistry. Using a retrosynthetic analysis, the structural analogues have been assembled from three relatively accessible building blocks. The solid-phase chemistry...... including MSNT-mediated esterification of both support-bound alcohols and carboxylic acids has been implemented successfully. Copyright (C) 1996 Elsevier Science Ltd....

  17. Alkaloids of family Amaryllidaceae and their analogues as potential drugs

    OpenAIRE

    Kavková, Zuzana

    2016-01-01

    Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate: Zuzana Kavková Supervisor: doc. Ing. Lucie Cahlíková, Ph.D. Title of diploma thesis: Alkaloids of family Amaryllidaceae and their analogues as potential drugs The object of this diploma thesis was to prepare derivatives of alkaloids of Amaryllidaceae family and to deal with their biological activity. These alkaloids are famous for their antibacterial, antiinfectives, a...

  18. Antineoplastic Efficacy of Novel Polyamine Analogues in Human Breast Cancer

    Science.gov (United States)

    2006-06-01

    product analogs. J Am Chem Soc 1978; 100: 2551–2553. 39 Burri C, Brun R. Eflornithine for the treatment of human African trypanosomiasis . Parasitol Res...ototoxicity) at high therapeutic doses [29]. Currently, DFMO is the front-line agent in the treatment of African trypanosomiasis and is undergoing...Polyamine Analogues in Human Breast Cancer. PRINCIPAL INVESTIGATOR: Yi Huang, M.D., Ph.D. CONTRACTING ORGANIZATION: Johns

  19. Bisphenol A and Its Analogues Activate Human Pregnane X Receptor

    OpenAIRE

    Sui, Yipeng; Ai, Ni; Park, Se-Hyung; Rios-Pilier, Jennifer; Perkins, Jordan T.; Welsh, William J.; Zhou, Changcheng

    2012-01-01

    Background: Bisphenol A (BPA) is a base chemical used extensively in many consumer products. BPA and its analogues are present in environmental and human samples. Many endocrine-disrupting chemicals, including BPA, have been shown to activate the pregnane X receptor (PXR), a nuclear receptor that functions as a master regulator of xenobiotic metabolism. However, the detailed mechanism by which these chemicals activate PXR remains unknown. Objective: We investigated the mechanism by which BPA ...

  20. Global analytic treatment of terrestrial photogrammetric networks

    CERN Document Server

    Mayoud, M

    1980-01-01

    In order to solve certain special CERN metrology problems, analytical terrestrial photogrammetry may have some advantages which are first discussed along with their drawbacks and limitations. In this application, it is necessary to carry out a rigorous and global adjustment of the observations and simultaneously process all the perspective ray bundles. The basic principles, the least squares solution and the stochastic analysis of the results are presented. However, for the CERN project, one wonders if the production of digital theodolites is going to reduce the advantages of the photogrammetric method. (12 refs).