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Sample records for arabia terra mars

  1. Supervolcanoes Within an Ancient Volcanic Province in Arabia Terra, Mars

    Science.gov (United States)

    Michalski, Joseph. R.; Bleacher, Jacob E.

    2014-01-01

    Several irregularly shaped craters located within Arabia Terra, Mars represent a new type of highland volcanic construct and together constitute a previously unrecognized martian igneous province. Similar to terrestrial supervolcanoes, these low-relief paterae display a range of geomorphic features related to structural collapse, effusive volcanism, and explosive eruptions. Extruded lavas contributed to the formation of enigmatic highland ridged plains in Arabia Terra. Outgassed sulfur and erupted fine-grained pyroclastics from these calderas likely fed the formation of altered, layered sedimentary rocks and fretted terrain found throughout the equatorial region. Discovery of a new type of volcanic construct in the Arabia volcanic province fundamentally changes the picture of ancient volcanism and climate evolution on Mars. Other eroded topographic basins in the ancient Martian highlands that have been dismissed as degraded impact craters should be reconsidered as possible volcanic constructs formed in an early phase of widespread, disseminated magmatism on Mars.

  2. Prospecting for Methane in Arabia Terra, Mars - First Results

    Science.gov (United States)

    Allen, Carlton C.; Oehler, Dotoyhy Z.; Venechuk, Elizabeth M.

    2006-01-01

    Methane has been measured in the Martian atmosphere at concentrations of approx. 10 ppb. Since the photochemical lifetime of this gas is approx. 300 years, it is likely that methane is currently being released from the surface. Possible sources for the methane include 1) hydrothermal activity, 2) serpentinization of basalts and other water-rock interactions, 3) thermal maturation of sedimentary organic matter, and 4) metabolism of living bacteria. Any such discovery would revolutionize our understanding of Mars. Longitudinal variations in methane concentration, as measured by the Planetary Fourier Spectrometer (PFS) on Mars Express, show the highest values over Arabia Terra, Elysium Planum, and Arcadia-Memnonia, suggesting localized areas of methane release. We are using orbital data and methodologies derived from petroleum exploration in an attempt to locate these release points.

  3. Possible ancient giant basin and related water enrichment in the Arabia Terra province, Mars

    Science.gov (United States)

    Dohm, J.M.; Barlow, N.G.; Anderson, R.C.; Williams, J.-P.; Miyamoto, H.; Ferris, J.C.; Strom, R.G.; Taylor, G.J.; Fairen, A.G.; Baker, V.R.; Boynton, W.V.; Keller, J.M.; Kerry, K.; Janes, D.; Rodriguez, J.A.P.; Hare, T.M.

    2007-01-01

    A circular albedo feature in the Arabia Terra province was first hypothesized as an ancient impact basin using Viking-era information. To test this unpublished hypothesis, we have analyzed the Viking era-information together with layers of new data derived from the Mars Global Surveyor (MGS) and Mars Odyssey (MO) missions. Our analysis indicates that Arabia Terra is an ancient geologic province of Mars with many distinct characteristics, including predominantly Noachian materials, a unique part of the highland-lowland boundary, a prominent paleotectonic history, the largest region of fretted terrain on the planet, outflow channels with no obvious origins, extensive exposures of eroded layered sedimentary deposits, and notable structural, albedo, thermal inertia, gravity, magnetic, and elemental signatures. The province also is marked by special impact crater morphologies, which suggest a persistent volatile-rich substrate. No one characteristic provides definitive answers to the dominant event(s) that shaped this unique province. Collectively the characteristics reported here support the following hypothesized sequence of events in Arabia Terra: (1) an enormous basin, possibly of impact origin, formed early in martian history when the magnetic dynamo was active and the lithosphere was relatively thin, (2) sediments and other materials were deposited in the basin during high erosion rates while maintaining isostatic equilibrium, (3) sediments became water enriched during the Noachian Period, and (4) basin materials were uplifted in response to the growth of the Tharsis Bulge, resulting in differential erosion exposing ancient stratigraphic sequences. Parts of the ancient basin remain water-enriched to the present day. ?? 2007 Elsevier Inc. All rights reserved.

  4. Active aeolian processes on Mars: A regional study in Arabia and Meridiani Terrae

    Science.gov (United States)

    Silvestro, S.; Vaz, D.A.; Fenton, L.K.; Geissler, P.E.

    2011-01-01

    We present evidence of widespread aeolian activity in the Arabia Terra/Meridiani region (Mars), where different kinds of aeolian modifications have been detected and classified. Passing from the regional to the local scale, we describe one particular dune field in Meridiani Planum, where two ripple populations are distinguished by means of different migration rates. Moreover, a consistent change in the ripple pattern is accompanied by significant dune advancement (between 0.4-1 meter in one Martian year) that is locally triggered by large avalanche features. This suggests that dune advancement may be common throughout the Martian tropics. ?? 2011 by the American Geophysical Union.

  5. Testing Formation Theories of NW Arabia Terra, Mars: New Clues from Old Craters

    Science.gov (United States)

    Robbins, S. J.; Hynek, B. M.

    2008-03-01

    Northwest Arabia Terra has topography and crater populations indicating a unique history. We directly tested two proposed formation mechanisms. Crater size-frequency and d/D ratios suggest neither scenario is easily reconcilable with the new datasets.

  6. Aram Dorsum, Candidate ExoMars Rover Landing Site: a Noachian Inverted Fluvial Channel System in Arabia Terra Mars

    Science.gov (United States)

    Balme, Matthew; Grindrod, Peter; Sefton-Nash, Elliot; Davis, Joel; Gupta, Sanjeev; Fawdon, Peter

    2016-04-01

    Much of Mars' Noachian-aged southern highlands is dissected by systems of fluvial channels and valleys > 3.7 Ga in age. Arabia Terra, lying between the southern highlands and the northern lowlands, is similarly ancient, yet apparently has few valley networks. This regional lack of valley networks only matches Noachian precipitation predictions from climate models if the Noachian climate was dry and cold [1]. In this scenario, highlands dissection was caused by transient flows of meltwater from large, regionally restricted ice-bodies. However, new results [2,3] show that Arabia Terra is not as poorly dissected as previously thought, and in fact there are extensive networks of inverted channel systems. Here, we describe an example of such a system - Aram Dorsum - which has been studied extensively as an ExoMars Rover candidate landing site. Aram Dorsum is an ~100 km long, 1-2 km wide, branching, flat-topped ridge system, in western Arabia Terra. We have mapped the system using CTX images, DEMs and other data. We interpret the ridge system to be fluvial in origin, preserved in positive relief due to infill and differential erosion; this working hypothesis is used as a conceptual framework for the study. Aram Dorsum is a branching, multi-level, contributory network, set in surrounding floodplains-like material. This demonstrates that it was a relatively long-lived, aggradational fluvial system, rather than an erosional outflow or bedrock-carved fluvial channel. Interestingly, the system shows little evidence for unconfined lateral channel migration, so there must have been significant bank stability. Aram Dorsum was therefore probably once a sizable river and, as just one example of many similar systems, is an exemplar for the middle part of a regional sediment transport system that could have extended from the southern highlands to the northern lowlands. Like Aram Dorsum, many of these other recently-recognized fluvial systems have an origin more consistent with

  7. The sedimentology and dynamics of crater-affiliated wind streaks in western Arabia Terra, Mars and Patagonia, Argentina

    Science.gov (United States)

    Rodriguez, J.A.P.; Tanaka, K.L.; Yamamoto, A.; Berman, D.C.; Zimbelman, J.R.; Kargel, J.S.; Sasaki, S.; Jinguo, Y.; Miyamoto, H.

    2010-01-01

    Wind streaks comprise recent aeolian deposits that have been extensively documented on Venus, Earth and Mars. Martian wind streaks are among the most abundant surface features on the planet and commonly extend from the downwind margins of impact craters. Previous studies of wind streaks emerging from crater interior deposits suggested that the mode of emplacement was primarily related to the deposition of silt-sized particles as these settled from plumes. We have performed geologic investigations of two wind streaks clusters; one situated in western Arabia Terra, a region in the northern hemisphere of Mars, and another in an analogous terrestrial site located in southern Patagonia, Argentina, where occurrences of wind streaks emanate from playas within maar craters. In both these regions we have identified bedforms in sedimentary deposits on crater floors, along wind-facing interior crater margins, and along wind streaks. These observations indicate that these deposits contain sand-sized particles and that sediment migration has occurred via saltation from crater interior deposits to wind streaks. In Arabia Terra and in Patagonia wind streaks initiate from crater floors that contain lithic and evaporitic sedimentary deposits, suggesting that the composition of wind streak source materials has played an important role in development. Spatial and topographic analyses suggest that regional clustering of wind streaks in the studied regions directly correlates to the areal density of craters with interior deposits, the degree of proximity of these deposits, and the craters' rim-to-floor depths. In addition, some (but not all) wind streaks within the studied clusters have propagated at comparable yearly (Earth years) rates. Extensive saltation is inferred to have been involved in its propagation based on the studied terrestrial wind streak that shows ripples and dunes on its surface and the Martian counterpart changes orientation toward the downslope direction where it

  8. Fresh Shallow Valleys in Northern Arabia Terra: Evidence for a Late, Widespread Period of Aqueous Activity on Mars

    Science.gov (United States)

    Wilson, S. A.; Howard, A. D.; Moore, J. M.; Grant, J. A., III

    2015-12-01

    Concentrations of fresh shallow valleys (FSVs) on Mars occur between ~30-45° in both hemispheres as well as near the equator (e.g., Gale crater and vicinity). FSVs in the northern hemisphere occur along the dichotomy boundary, with the highest concentration in northern Arabia Terra from 35-40°N between 0-20ºE. In this region, FSVs developed both on and away from ejecta of relatively fresh craters, making the direct association between impact processes and formation less likely. Crater statistics and cross-cutting relationships indicate the formation of FSVs terminated prior to about 1.4 Ga, suggesting they may be contemporaneous with alluvial fan and delta formation in the equatorial and mid-latitudes. Many FSV systems are 150+ km long, and in several cases appear to cross depressions that were likely filled with ice or water during FSV formation. Most FSV systems could have formed from a single episode of erosion but incision of the main channel in some locations may imply episodic formation. One long valley system in N. Arabia Terra with an incised channel (100 m wide, up to 10 m deep) yields formative discharges in the range of 100-200 m3/s assuming sand sized particles and a flow depth of 0.25 m, consistent with formation via snowmelt. The grain size is unknown, therefore discharges could range from 10s m3/s for active transport of fine sand to 1000 m3/s for gravel sized grains. Approximately 25 small craters (diameters ranging from ~2-10 km) have single channels extending outward from their rim, implying overflow of the crater and the possible presence of a deep lake. Widespread occurrence of FSVs, their similar morphology, and modest state of degradation is consistent with most forming during one or more global intervals of favorable climate, likely through snowmelt from surface or sub-ice flows during the Hesperian.

  9. Discovery of a Plains Caldera Complex and Extinct Lava Lake in Arabia Terra, Mars: Implications for the Discovery of Additional Highland Volcanic Source Regions

    Science.gov (United States)

    Bleacher, Jacob; Michalski, Joseph

    2012-01-01

    Several irregularly shaped topographic depressions occur near the dichotomy boundary in northern Arabia Terra, Mars. The geomorphology of these features suggests that they formed by collapse, opposed to meteor impact. At least one depression (approx.55 by 85 km) displays geologic features indicating a complex, multi-stage collapse history. Features within and around the collapse structure indicate volcanic processes. The complex occurs within Hesperian ridged plains of likely volcanic origin and displays no crater rim or evidence for ejecta. Instead the depression consists of a series of circumferential graben and down-dropped blocks which also display upper surfaces similar to ridged plain lavas. Large blocks within the depression are tilted towards the crater center, and display graben that appear to have originally been linked with circumferential graben outside of the complex related to earlier collapse events. A nearly 700 m high mound exists along a graben within the complex that might be a vent. The deepest depression displays two sets of nearly continuous terraces, which we interpret as high-stands of a drained lava lake. These features appear similar to the black ledge described during the Kilauea Iki eruption in 1959. A lacustrine origin for the terraces seems unlikely because of the paucity of channels found in or around the depression that could be linked to aqueous surface processes. In addition, there is no obvious evidence for lacustrine sediments within the basin. Together with the presence of significant faulting that is indicative of collapse we conclude that this crater complex represents a large caldera formed in the Late Noachian to Early Hesperian. Other linear and irregular depressions in the region also might be linked to ancient volcanism. If that hypothesis is correct, it suggests that northern Arabia Terra could contain a large, previously unrecognized highland igneous province. Evacuation of magma via explosive and effusive activity

  10. Extension Across Tempe Terra, Mars from MOLA Topographic Measurements

    Science.gov (United States)

    Harrington, B. W.; Phillips, R. J.; Golombek, M. P.

    1999-01-01

    Previously, methods of estimating the extension across grabens and rifts on Mars by necessity relied on photogeologic methods such as shadow measurement, crater ellipticity, or photoclinometry. With the new data being returned by the Mars Global Surveyor, specifically from the Mars Orbital Laser Altimeter (MOLA), it is now possible to directly measure the depths of these structures and therefore to estimate more accurately the amount of extension. Here we provide an example of this new approach in the Tempe Terra region. Additional information is contained in the original extended abstract.

  11. Ancient Giant Basin/Aquifer System in the Arabia Region, Mars

    Science.gov (United States)

    Dohm, James M.; Barlow, Nadine; Williams, Jean-Pierre; Baker, Victor R.; Anderson, Robert C.; Boynton, William V.; Fairen, Alberto G.; Hare, Trent M.

    2004-01-01

    Ancient geologic/hydrologic phenomena on Mars observed through the magnetic data [1,2] provide windows to the ancient past through the younger Argyre and Hellas impacts [e.g., 3,4], the northern plains basement [5], and the Tharsis and Elysium magmatic complexes (recently referred to as superplumes [6,7]). These signatures, coupled with highly degraded macrostructures (tectonic features that are tens to thousands of km-long [8]), reflect an energetic planet during its embryonic development (.5 Ga or so of activity) with an active dynamo and magnetosphere [1,2,6]. One such window into the ancient past occurs northwest of the Hellas impact basin in Arabia Terra. Arabia Terra is one of the few water-rich equatorial regions of Mars, as indicated through impact crater [9] and elemental [10,11] information. This region records many unique traits, including stratigraphy, topography, cratering record, structural character, geomorphology, and geophysical, elemental, albedo, and thermal inertia signatures. We interpret these to collectively indicate a possible ancient giant impact basin that later became an important aquifer, as it provided yet another source of water for the formation of putative water bodies that occupied the northern plains [12,13] and addresses possible water-related characteristics that may be observed at the Opportunity landing site. This basin is antipodal to Tharsis and estimated to be at least 3,000 km in diameter.

  12. Identifying the Pre-Tharsis Structures Associated with the Terra Sirenum Region, Mars

    Science.gov (United States)

    Anderson, R. C.; Dohm, J. M.; Robbins, S.; Schroeder, J.

    2014-07-01

    The Terra Sirenum region contains some of the oldest stratigraphic units found on Mars. Examination of the structures and units provides an excellent window into clarifying the processes that influenced the early geologic evolution of Mars.

  13. Terra Sirenum: Window into Pre-Tharsis and Tharsis Phases of Mars Evolution

    Science.gov (United States)

    Anderson, R. C.; Dohm, J. M.; Robbins, S.; Hynek, B.; Andrews-Hanna, J.

    2012-03-01

    The Terra Sirenum region contains some of the oldest stratigraphic units on Mars. Detailed examination of the structures and units provides an excellent window into identifying the processes that influenced the early geologic evolution of Mars.

  14. MOLA Topography of Small Volcanoes in Tempe Terra and Ceraunius Fossae, Mars: Implications for Eruptive Styles

    Science.gov (United States)

    Wong, M. P.; Sakimoto, S. E. H.; Garvin, J. B.

    2001-01-01

    We use Mars Orbiter Laser Altimeter (MOLA) data to measure small volcanoes in the Tempe Terra and Ceraunius Fossae regions of Mars. We find that previous geometry estimates based on imagery alone are inaccurate, but MOLA data support image-based interpretations of eruptive style. Additional information is contained in the original extended abstract.

  15. TERRA.

    Science.gov (United States)

    Locke, Kirsty

    1997-01-01

    TERRA (Teaching Ecological Responsibility, Recreation, and Adventure) is an integrated, one-semester, four-course program in environmental science, environmental English, independent geography, and outdoor education for grades 11 and 12 in New Liskeard, Ontario. Program activities include outdoor adventure, environmental research projects,…

  16. Blueberries on Earth and Mars: Correlations Between Concretions in Navajo Sandstone and Terra Meridiani on Mars.

    Science.gov (United States)

    Mahaney, W. C.; Milner, M. W.; Netoff, D.; Dohm, J.; Kalm, V.; Krinsley, D.; Sodhi, R. N.; Anderson, R. C.; Boccia, S.; Malloch, D.; Kapran, B.; Havics, A.

    2008-12-01

    Concretionary Fe-Mn-rich nodular authigenic constituents of Jurassic Navajo sandstone (moki marbles) bear a certain relationship to similar concretionary forms ('blueberries') observed on Mars. Their origin on Earth is considered to invoke variable redox conditions with underground fluids penetrating porous quartz-rich sandstone leading to precipitation of hematite and goethite-rich material from solution, generally forming around a central nucleus of fine particles of quartz and orthoclase, recently verified by XRD and SEM-EDS analyses. At the outer rim/inner nucleus boundary, bulbous lobes of fine-grained quartz often invade and fracture the outer rim armored matrix. The bulbous forms are interpreted to result from fluid explusion from the inner concretionary mass, a response to pressure changes accompanying overburden loading. Moki marbles, harder than enclosing rock, often weather out of in situ sandstone outcrops that form a surface lag deposit of varnished marbles that locally resemble desert pavement. The marbles appear morphologically similar to 'blueberries' identified on the martian surface in Terra Meridiani through the MER-1 Opportunity rover. On Earth, redox fluids responsible for the genesis of marbles may have emanated from deep in the crust (often influenced by magmatic processes). These fluids, cooling to ambient temperatures, may have played a role in the genesis of the cemented outer rim of the concretions. The low frequency of fungi filaments in the marbles, contrasts with a high occurrence in Fe-encrusted sands of the Navajo formation [1], indicating that microbial content is of secondary importance in marble genesis relative to the fluctuating influx of ambient groundwater. Nevertheless, the presence of filaments in terrestrial concretions hints at the possibility of discovering fossil/extant life on Mars, and thus should be considered as prime targets for future reconnaissance missions to Mars. 1] Mahaney, W.C., et al. (2004), Icarus, 171, 39-53.

  17. A cold-wet middle-latitude environment on Mars during the Hesperian-Amazonian transition: Evidence from northern Arabia valleys and paleolakes

    Science.gov (United States)

    Wilson, Sharon A.; Howard, Alan D.; Moore, Jeffrey M.; Grant, John A.

    2016-09-01

    The growing inventory of post-Noachian fluvial valleys may represent a late, widespread episode of aqueous activity on Mars, contrary to the paradigm that fluvial activity largely ceased around the Noachian-Hesperian boundary. Fresh shallow valleys (FSVs) are widespread from ~30 to 45° in both hemispheres with a high concentration in northern Arabia Terra. Valleys in northern Arabia Terra characteristically start abruptly on steeper slopes and terminate in topographic depressions at elevations corresponding to model-predicted lake levels. Longer valley systems flowed into and out of chains of paleolakes. Minimum discharges based on the dimensions of the incised channel assuming medium to coarse sand-size grains ranges from tens to hundreds of m3 s-1, respectively, consistent with formation via snowmelt from surface or sub-ice flows. Hydrologic calculations indicate the valleys likely formed in hundreds of years or less, and crater statistics constrain the timing of fluvial activity to between the Hesperian and middle Amazonian. Several craters with channels extending radially outward supports evidence for overflow of interior crater lakes possibly fed by groundwater. Most FSVs occur away from young impact craters which make an association with impact processes improbable. The widespread occurrence of FSVs along with their similar morphology and shared modest state of degradation is consistent with most forming during a global interval of favorable climate, perhaps contemporaneous with alluvial fan formation in equatorial and midlatitudes. Evidence for a snowmelt-based hydrology and considerable depths of water on the landscape in Arabia supports a cold, wet, and possibly habitable environment late in Martian history.

  18. Columbus crater and other possible groundwater-fed paleolakes of Terra Sirenum, Mars

    Science.gov (United States)

    Wray, J.J.; Milliken, R.E.; Dundas, C.M.; Swayze, G.A.; Andrews-Hanna, J. C.; Baldridge, A.M.; Chojnacki, M.; Bishop, J.L.; Ehlmann, B.L.; Murchie, S.L.; Clark, R.N.; Seelos, F.P.; Tornabene, L.L.; Squyres, S. W.

    2011-01-01

    Columbus crater in the Terra Sirenum region of the Martian southern highlands contains light-toned layered deposits with interbedded sulfate and phyllosilicate minerals, a rare occurrence on Mars. Here we investigate in detail the morphology, thermophysical properties, mineralogy, and stratigraphy of these deposits; explore their regional context; and interpret the crater's aqueous history. Hydrated mineral-bearing deposits occupy a discrete ring around the walls of Columbus crater and are also exposed beneath younger materials, possibly lava flows, on its floor. Widespread minerals identified in the crater include gypsum, polyhydrated and monohydrated Mg/Fe-sulfates, and kaolinite; localized deposits consistent with montmorillonite, Fe/Mg-phyllosilicates, jarosite, alunite, and crystalline ferric oxide or hydroxide are also detected. Thermal emission spectra suggest abundances of these minerals in the tens of percent range. Other craters in northwest Terra Sirenum also contain layered deposits and Al/Fe/Mg-phyllosilicates, but sulfates have so far been found only in Columbus and Cross craters. The region's intercrater plains contain scattered exposures of Al-phyllosilicates and one isolated mound with opaline silica, in addition to more common Fe/Mg-phyllosilicates with chlorides. A Late Noachian age is estimated for the aqueous deposits in Columbus, coinciding with a period of inferred groundwater upwelling and evaporation, which (according to model results reported here) could have formed evaporites in Columbus and other craters in Terra Sirenum. Hypotheses for the origin of these deposits include groundwater cementation of crater-filling sediments and/or direct precipitation from subaerial springs or in a deep (???900 m) paleolake. Especially under the deep lake scenario, which we prefer, chemical gradients in Columbus crater may have created a habitable environment at this location on early Mars. ?? 2011 by the American Geophysical Union.

  19. Geologic Map of MTM -20012 and -25012 Quadrangles, Margaritifer Terra Region of Mars

    Science.gov (United States)

    Grant, J. A.; Wilson, S.A.; Fortezzo, C.M.; Clark, D.A.

    2009-01-01

    Mars Transverse Mercator (MTM) -20012 and -25012 quadrangles (lat 17.5 deg - 27.5 deg S., long 345 deg - 350 deg E.) cover a portion of Margaritifer Terra near the east end of Valles Marineris. The map area consists of a diverse assemblage of geologic surfaces including isolated knobs of rugged mountainous material, heavily cratered and dissected ancient highland material, a variety of plains materials, chaotic terrain materials, and one of the highest densities of preserved valleys and their associated deposits on the planet (Saunders, 1979; Baker, 1982; Phillips and others, 2000, 2001). The map area is centered on a degraded, partially filled, ~200-km-diameter impact structure (lat 22 deg S., long 347.5 deg E.), informally referred to as Parana basin, located between Parana Valles to the east and Loire Valles to the west. Parana Valles is a network of multidigitate, mostly east-west-oriented valleys that flowed west and discharged into Parana basin (Grant, 1987, 2000; Grant and Parker, 2002). Loire Valles, broadly comparable in length to the Grand Canyon on Earth, has a deeply incised channel within the map area that originates at the west-northwest edge of Erythraeum Chaos within Parana basin (Grant, 1987, 2000; Grant and Parker, 2002; Strom and others, 2000). Parana and Loire Valles, combined with Samara Valles to the west, form one of the most laterally extensive, well-integrated valley networks on Mars (Grant, 2000) and record a long history of modification by fluvial processes. The origin and morphology of the valley networks, therefore, provide insight into past environmental conditions, whereas their relation with other landforms helps constrain the timing and role of fluvial processes in the evolution and modification of the Margaritifer Terra region.

  20. Amazonian-aged fluvial system and associated ice-related features in Terra Cimmeria, Mars

    Science.gov (United States)

    Adeli, Solmaz; Hauber, Ernst; Kleinhans, Maarten; Le Deit, Laetitia; Platz, Thomas; Fawdon, Peter; Jaumann, Ralf

    2016-10-01

    The Martian climate throughout the Amazonian is widely believed to have been cold and hyper-arid, very similar to the current conditions. However, ubiquitous evidence of aqueous and glacial activity has been recently reported, including channels that can be tens to hundreds of kilometres long, alluvial and fluvial deposits, ice-rich mantles, and glacial and periglacial landforms. Here we study a ∼340 km-long fluvial system located in the Terra Cimmeria region, in the southern mid-latitudes of Mars. The fluvial system is composed of an upstream catchment system with narrow glaciofluvial valleys and remnants of ice-rich deposits. We observe depositional features including fan-shaped deposits, and erosional features such as scour marks and streamlined islands. At the downstream section of this fluvial system is an outflow channel named Kārūn Valles, which displays a unique braided alluvial fan and terminates on the floor of the Ariadnes Colles basin. Our observations point to surface runoff of ice/snow melt as the water source for this fluvial activity. According to our crater size-frequency distribution analysis the entire fluvial system formed during early to middle Amazonian, between ∼ 1.8-0.2+0.2 Ga to 510-40+40 Ma. Hydraulic modelling indicates that the Kārūn Valles and consequently the alluvial fan formation took place in geologically short-term event(s). We conclude that liquid water was present in Terra Cimmeria during the early to middle Amazonian, and that Mars during that time may have undergone several episodic glacial-related events.

  1. Geologic map of MTM -15027, -20027, -25027, and -25032 quadrangles, Margaritifer Terra region of Mars

    Science.gov (United States)

    Irwin, Rossman P.; Grant, John A.

    2013-01-01

    Mars Transverse Mercator (MTM) quadrangles −15027, −20027, −25027, and −25032 (lat 12.5°−28° S., long 330°−335° E. and lat 22.5°−28° S., long 324.5°−330° E.) in southwestern Margaritifer Terra include diverse erosional landforms, sedimentary deposits, and tectonic structures that record a long geologic and geomorphic history. The northeastern regional slope of the pre-Noachian crustal dichotomy (as expressed along the Chryse trough) and structures of the informally named Middle Noachian or older Holden and Ladon impact basins dominate the topography of the map area. A series of mesoscale outflow channels, Uzboi, Ladon, and Morava Valles, integrated these formerly enclosed basins by overflow and incision around the Noachian/Hesperian transition, although some flooding may have occurred earlier. The area includes excellent examples of Late Noachian to Hesperian valley networks, dissected crater rims, alluvial fans, deltas, and light-toned layered deposits, particularly in Holden and Eberswalde craters. Structural forms include Tharsis-radial grabens, Hesperian wrinkle ridges, floor-fractured impact craters, and severely disrupted chaotic terrains. These well-preserved landforms and sedimentary deposits represent multiple erosional epochs and discrete flooding events, which provide significant insight into the geomorphic processes and climate change on early Mars.

  2. Analysis of crater valleys, Noachis Terra, Mars: Evidence of fluvial and glacial processes

    Science.gov (United States)

    Hobbs, S. W.; Clarke, J. D. A.; Paull, D. J.

    2016-05-01

    The precise mechanism for the formation and evolution of crater valley networks in the Martian southern highlands remains under debate, with precipitation, groundwater flow, and melting induced by impact being suggested. We studied valley networks within four craters of the Noachis Terra highlands that were representative of similar features in Noachis Terra and where orbital data existed for analysis in order to characterise their morphology and infer possible processes involved in their formation and evolution. We found evidence for valleys carved by liquid water and ice-related processes. This included strong evidence of liquid water-based valley formation through melting of ice-rich deposits throughout our study area, suggesting an alternative to previously suggested rainfall or groundwater-based scenarios. The location of these valleys on steeply sloping crater walls, as opposed to the shallow slopes of the highlands where Martian valleys are typically found, suggested that our 'fluvial' valleys had not evolved a more structured fluvial morphology as valley networks found on the Martian plains. Our studied valleys' association with ice-rich material and abundant evidence for erosion caused by downslope flow of ice-rich material are consistent with a cold, wet Mars hypothesis where accumulation, flow, and melting of ice have been dominant factors in eroding crater valleys. Additionally, analysis of valley morphology with slope and aspect suggested a greater dependence on local geology and presence of volatiles than larger valley networks, though ice-related valleys were consistently wider for their length than valleys assessed as fluvial carved. We assessed that local conditions such as climate, geology, and availability of ice-rich material played a major role in the erosion of crater valleys at our study site.

  3. Detection and context of hydrated mineralogy in the Tyrrhena Terra region, Mars

    Science.gov (United States)

    den Haan, J.; Zegers, T. E.; van Ruitenbeek, F. J. A.; van der Werff, H. M. A.; Rossi, A.

    2008-09-01

    Introduction The discovery of phyllosilicates on Mars [1] has had major implications on the perceived geologic and climatologic evolution of Mars [2]. Not only do phyllosilicates represent a `wet' period on Mars, they might also represent a potentially favorable environment for life. The phyllosilicates have so far exclusively been found in or close to ancient Noachian highland terrain. Those phyllosilicate deposits studied (e.g. [3]) show a clear association between hydrated mineralogy and heavily eroded and crater-saturated outcrops. Phyllosilicates on Earth are associated with a wide variety of geological processes (volcanism, metamorphism, hydrothermal alteration, sedimentation). The occurrence of phyllosilicates on Mars may be equally diverse in nature. To be able to place constraints on the early Martian environment, the processes by which these phyllosilicates formed need to be reconstructed. To derive this information from individual phyllosilicate deposits, it is necessary to interpret their composition in relation to their geological context and relative time relationships. We conducted such an integrated hyperspectral and geological study of the Tyrrhena Terra region. Data products ad methods HRSC data products (both image at 12 m/pixel and stereo-derived DTMs) are used for examining geologic cross-cutting relationships, geomorphologic landforms and visual determination of unit boundaries. Odyssey THEMIS nighttime TIR images are analyzed for spatial variations in thermal inertia. Where available, HRSC is supplemented by higher-resolution visible observations of CTX or MOC. Hyperspectral analysis is conducted using data from the OMEGA hyperspectral instrument. In order to batch-process large amounts of OMEGA data, an IDL/ENVI tool was developed on top of the existing SOFT04, distributed by PSA. The applied atmospheric correction assumes that atmospheric contributions are multiplicative, and follow a power-law distribution with altitude [4]. The ratio of

  4. Geology of Libya Montes and the Interbasin Plains of Northern Tyrrhena Terra, Mars: Project Introduction and First Year Work Plan

    Science.gov (United States)

    Skiner, J. A., Jr.; Rogers, A. D.; Seelos, K. D.

    2009-01-01

    The highland-lowland boundary (HLB) of Mars is interpreted to be a complex tectonic and erosional transition that may hold evidence for past geologic processes and environments. The HLB-abutting margin of the Libya Montes and the interbasin plains of northern Tyrrhena Terra display an exceptional view of the earliest to middle history of Mars that has yet to be fully characterized. This region contains some of the oldest exposed materials on the Martian surface as well as aqueous mineral signatures that may be potential chemical artifacts of early highland formational processes. However, a full understanding of the regions geologic and stratigraphic evolution is remarkably lacking. Some outstanding questions regarding the geologic evolution of Libya Montes and northern Tyrrhena Terra in-clude: Does combining geomorphology and composition advance our understanding of the region s evolution? Can highland materials be subdivided into stratigraphically discrete rock and sediment sequences? What do major physiographic transitions imply about the balanced tectonism, climate change, and erosion? Where is the erosional origin and what is the post-depositional history of channel and plains units? When and in what types of environments did aqueous mineral signatures arise? This abstract introduces the geologic setting, science rationale, and first year work plan of a recently-funded 4-year geologic mapping proposal (project year = calendar year). The objective is to delineate the geologic evolution of Libya Montes and northern Tyrrhena Terra at 1:1M scale using both classical geomorphological and compositional mapping techniques. The funded quadrangles are MTMs 00282, -05282, -10282, 00277, -05277, and -10277.

  5. Multiple Episodes of Recent Gully Activity Indicated by Gully Fan Stratigraphy in Eastern Promethei Terra, Mars.

    Science.gov (United States)

    Schon, S.; Head, J.; Fassett, C.

    2008-09-01

    Introduction Gullies are considered among the youngest geomorphic features on Mars based upon their stratigraphic relationships, superposition on steep slopes and distinctive morphology in unconsolidated sediment. Multiple formation hypotheses have been proposed, which can be divided into three broad classes: entirely dry mechanisms (e.g., [1,2]), wet mechanisms invoking groundwater or ground ice (e.g., [3,4]) and wet mechanisms invoking surficial meltwater (e.g., [5,6,7,8]). It has been difficult to differentiate between these hypotheses based upon past observations and it remains possible that gullies are polygenetic landforms. This study presents stratigraphic relationships in the depositional fan of a crater wall gully system that suggest: (1) multiple episodes of alluvial fan-style deposition, (2) very recent depositional activity that is younger than a newly recognized rayed crater, and (3) surficial snowmelt as the most likely source of these multiple episodes of recent gully activity. Gully-Fan Stratigraphy In Eastern Promethei Terra an ~5 km-diameter crater is observed with a well-developed gully system (Fig. 1) and several smaller gullies in its northnortheast wall. The large gully system (composed of a small western gully and larger eastern gully) shows evidence for incision into the crater wall country rock and has multiple contributory sub-alcoves and channels. The depositional fan associated with this gully system is bounded on its western side by a small arcuate ridge swell that is not observed on the eastern side of the fan. This ridge is interpreted as a moraine-like structure that may have bounded a glacially-formed depression into which the fan is deposited [8]. Similar depressions with bounding ridges are commonly observed in this latitude band (~30-50°S) in association with deeply incised gully alcoves [9,10,11]. This gully fan is composed of multiple lobes with distinct lobe contacts, incised channels, and cut-andfill deposits - all features

  6. Thermal Inertia, Albedo, and MOLA-derived Roughness for Terrains in the Terra Meridiani Area, Mars

    Science.gov (United States)

    Arvidson, R. E.; Deal, K.; Hynek, B. M.; Seelos, F. P., IV; Snider, N. O.; Mellon, M. T.; Garvin, J. B.

    2002-01-01

    Surface properties of layered deposits draped on dissected, cratered terrain in the Terra Meridiani area are analyzed using remote sensing data. The etched plains are cemented and differentially eroded, and the hematite plains are loose and drifting. Additional information is contained in the original extended abstract.

  7. Evidence for Noachian flood volcanism in Noachis Terra, Mars, and the possible role of Hellas impact basin tectonics

    Science.gov (United States)

    Rogers, A. D.; Nazarian, A. H.

    2013-05-01

    Spectral and imaging data sets from Mars Reconnaissance Orbiter and Mars Odyssey, as well as spectral and topographic data from Mars Global Surveyor, are used to understand the origin of in-place rock units found in the intercrater plains and Hellas circumferential graben floors of Noachis Terra, Mars. The rocky units are interpreted as effusive volcanic plains on the basis of broad areal extent, structural competence, association with topographic lows, distinct mineralogy from regolith, and lack of sedimentary textures or minerals associated with aqueous processes. Some rocky expanses contain at least two compositionally distinct units. The relatively light-toned unit exhibits a higher plagioclase/pyroxene ratio than the lower, dark-toned unit. Both units exhibit ~10% olivine enrichment compared to surrounding regolith. These units are heavily degraded and exhibit crater model ages between ~3.80 and 4.0 Ga, making these some of the oldest preserved volcanic plains accessible by remote sensing. They are found in association with Hellas ring structures, where the westward extent of these rocky units is limited to the outermost ring structure. Fracturing associated with the Hellas impact may have enabled magmas to ascend from the base of the crust in the circum-Hellas region. Identification of these units as volcanic materials extends previous estimates for volume of outgassed volatiles. Though the estimated volcanic volume increase is minor, the local effects could have been significant. The role of multi-ring impact basins in providing a spatial control on Martian highlands volcanism and subsurface mineralization may have been underestimated in the past.

  8. Geology of Holden Crater and the Holden and Ladon Multi-Ring Impact Basins, Margaritifer Terra, Mars

    Science.gov (United States)

    Irwin, R. P., III; Grant, J. A.

    2008-01-01

    Geologic mapping at 1:500K scale of Mars quads 15s027, 20s027, 25s027, and 25s032 (Fig. 1) is in progress to constrain the geologic and geomorphic history of southwestern Margaritifer Terra. This work builds on earlier maps at 1:5M [1] and 1:15M scales [2], recent to concurrent 1:500Kscale mapping of adjacent areas to the east [3-5], and studies of drainage basin evolution along the Uzboi-Ladon-M (ULM; the third valley in the sequence has no formal name) Valles basin overflow system and nearby watersheds [6-9]. Two of the six landing sites under consideration for the Mars Science Laboratory rover are in this map area, targeting finely layered, phyllosilicate-rich strata and alluvial fans in Holden crater [10-12] (26degS, 34degW, 150 km diameter) or deposits southeast of a likely delta in Eberswalde crater [13-16] (24degS, 33degW, 50 km in diameter). Diverse processes including larger and smaller impacts, a wide range in fluvial activity, and local to regional structural influences have all affected the surface morphology.

  9. Managed Aquifer Recharge (MAR Economics for Wastewater Reuse in Low Population Wadi Communities, Kingdom of Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Thomas M. Missimer

    2014-08-01

    Full Text Available Depletion of water supplies for potable and irrigation use is a major problem in the rural wadi valleys of Saudi Arabia and other areas of the Middle East and North Africa. An economic analysis of supplying these villages with either desalinated seawater or treated wastewater conveyed via a managed aquifer recharge (MAR system was conducted. In many cases, there are no local sources of water supply of any quality in the wadi valleys. The cost per cubic meter for supplying desalinated water is $2–5/m3 plus conveyance cost, and treated wastewater via an MAR system is $0–0.50/m3 plus conveyance cost. The wastewater reuse, indirect for potable use and direct use for irrigation, can have a zero treatment cost because it is discharged to waste in many locations. In fact, the economic loss caused by the wastewater discharge to the marine environment can be greater than the overall amortized cost to construct an MAR system, including conveyance pipelines and the operational costs of reuse in the rural environment. The MAR and associated reuse system can solve the rural water supply problem in the wadi valleys and reduce the economic losses caused by marine pollution, particularly coral reef destruction.

  10. Managed aquifer recharge (MAR) economics for wastewater reuse in low population wadi communities, Kingdom of Saudi Arabia

    KAUST Repository

    Missimer, T.M.

    2014-08-07

    Depletion of water supplies for potable and irrigation use is a major problem in the rural wadi valleys of Saudi Arabia and other areas of the Middle East and North Africa. An economic analysis of supplying these villages with either desalinated seawater or treated wastewater conveyed via a managed aquifer recharge (MAR) system was conducted. In many cases, there are no local sources of water supply of any quality in the wadi valleys. The cost per cubic meter for supplying desalinated water is $2-5/m3 plus conveyance cost, and treated wastewater via an MAR system is $0-0.50/m3 plus conveyance cost. The wastewater reuse, indirect for potable use and direct use for irrigation, can have a zero treatment cost because it is discharged to waste in many locations. In fact, the economic loss caused by the wastewater discharge to the marine environment can be greater than the overall amortized cost to construct an MAR system, including conveyance pipelines and the operational costs of reuse in the rural environment. The MAR and associated reuse system can solve the rural water supply problem in the wadi valleys and reduce the economic losses caused by marine pollution, particularly coral reef destruction. 2014 by the authors.

  11. Multi-agent gully processes: Evidence from the Monaro Volcanic Province, Australia and in Terra Cimmeria, Mars

    Science.gov (United States)

    Hobbs, S. W.; Paull, D. J.; Clarke, J. D. A.; Roach, Ian C.

    2016-03-01

    Comparison of the similarities and differences between terrestrial and Martian hillside gullies promotes understanding of how surface processes operate on both planets. Here we tested the viability of subsurface flow of water as a process affecting gully evolution. We compared gullies within the Monaro Volcanic Province near Cooma, New South Wales, Australia, to gullies possessing strong structural control near Gasa Crater, Terra Cimmeria, Mars. Although cursory examination of the Monaro gullies initially suggested strong evidence for aquifer erosion, detailed field surveys showed the evidence to be ambiguous. Instead a complex regime of erosion dependent on multiple conditions and processes such as local geology, surface runoff, dry mass wasting, and animal activity emerged. We found the morphology of gullies near Gasa Crater to be consistent with erosion caused by liquid water, while also being heavily influenced by the local environment, including slope and geology. Additionally, erosion at the Martian site was not consistent with evidence of subsequent, smaller scale erosion and channel modification by dry mass wasting. Local conditions thus play an important role in gully evolution, further highlighting that processes forming Martian gullies may be more diverse than initially thought.

  12. Geology of Libya Montes and the Interbasin Plains of Northern Tyrrhena Terra, Mars: First Year Results and Second Year Work Plan

    Science.gov (United States)

    Skinner, J. A., Jr.; Rogers, A. D.; Seelos, K. D.

    2010-01-01

    The Libya Montes-Tyrrhena Terra highland-lowland transitional zone of Mars is a complex tectonic and erosional region that contains some of the oldest exposed materials on the Martian surface as well as aqueous mineral signatures that may be potential chemical artifacts of early highland formational processes. Our 1:1M scale mapping project includes the geologic materials and landforms contained within MTMs 00282, -05282, -10282, 00277, - 05277, and -10277, which cover the highland portion of the transitional zone. The map region extends from the Libya Montes southward into Tyrrhena Terra and to the northern rim of Hellas basin and includes volcanic rocks of Syrtis Major Planum and a broad lowlying plain (palus) that forms a topographic divide between Isidis and Hellas basins. The objective of this project is to describe the geologic history of regional massif and plains materials by combining geomorphological and compositional mapping observations. This abstract summarizes the technical approaches and interim scientific results of Year 1 efforts and the expected work plan for Year 2 efforts.

  13. Regional-scale stratigraphy of surface units in Tyrrhena and Iapygia Terrae, Mars: insights into highland crustal evolution and alteration history

    Science.gov (United States)

    Rogers, A. Deanne; Fergason, Robin L.

    2011-01-01

    The compositional, thermophysical and geologic characteristics of surface units in Iapygia and Tyrrhena Terra (60°E-100°E, 0°-30°S) provide new insights into the compositional stratigraphy of the region. Intercrater plains are dominated by two surface units. The older unit (unit 1) is deficient in olivine and more degraded and likely consists of a mixture of impact, volcanic and sedimentary materials. The younger unit (unit 2) is enriched in olivine, exhibits a resistant morphology and higher thermal inertia, and likely represents volcanic infilling of plains. Units 1 and 2 bear a strong resemblance to those previously mapped in Mare Serpentis, a section of highlands crust located northwest of Hellas Basin. Thus, the two major intercrater plains units are even more widespread than previously thought and therefore likely constitute important components of Mars' highland stratigraphy. Many craters in the region contain high thermal inertia deposits (unit 3) that are compositionally identical to unit 2. These may have formed via volcanic infilling or may represent sedimentary materials that have been eroded from crater walls and lithified. Less common units include olivine and/or pyroxene-rich massifs and crater central peaks. These are primarily found within Hellas Basin rim units and may represent mantle materials brought toward the surface during the Hellas impact. Putative chloride deposits are primarily associated with olivine-deficient surfaces (unit 1) that may be heavily degraded occurrences of unit 2. The observations raise a variety of questions related to Martian crustal evolution and alteration that may have more widespread implications outside the study region.

  14. Mars

    CERN Document Server

    Elkins-Tanton, Linda T

    2010-01-01

    Mars exploration has never been more active, and our understanding of the planet is advancing rapidly. New discoveries reveal gullies carved by recent groundwater flow, thick ice deposits protected by rocks and soil even at the equator, and new evidence for lakes and seas in Mars' past. The Martian surface has some of the oldest planetary crust in the solar system, containing clues to conditions in early planets that cannot be obtained elsewhere.Beginning with a discussion of Mars as a planet in orbit, Mars, Revised Edition covers fundamental facts about this planet, including its mass and siz

  15. Mars

    CERN Document Server

    Day, Trevor

    2006-01-01

    Discusses the fundamental facts concerning this mysterious planet, including its mass, size, and atmosphere, as well as the various missions that helped planetary scientists document the geological history of Mars. This volume also describes Mars'' seasons with their surface effects on the planet and how they have changed over time.

  16. Saudi Arabia

    International Nuclear Information System (INIS)

    Saudi Arabia is a country of the first importance because of its oil reserves (26% of the known world reserves) and its oil production: the third of the whole Opec production. This energetic gold mine finances up to 75% of the budget and assures 90% of its exports. The capacity of Saudi Arabia to refine crude oil is now comparable to that of France. Nevertheless the inflexibility of government expenditures makes foreign investors necessary to a balanced industrial development. It is expected that the Board of Trade soon presents some dispositions in order to promote and ease the opening to foreign investors. (A.C.)

  17. Nature and origin of the hematite-bearing plains of Terra Meridiani based on analyses of orbital and Mars Exploration rover data sets

    OpenAIRE

    Arvidson, R.E.; Grotzinger, J.; Ehlmann, B. L.

    2006-01-01

    The ~5 km of traverses and observations completed by the Opportunity rover from Endurance crater to the Fruitbasket outcrop show that the Meridiani plains consist of sulfate-rich sedimentary rocks that are largely covered by poorly-sorted basaltic aeolian sands and a lag of granule-sized hematitic concretions. Orbital reflectance spectra obtained by Mars Express OMEGA over this region are dominated by pyroxene, plagioclase feldspar, crystalline hematite (i.e., concretions), and nano-phase iro...

  18. Exobiology site priorities for Mars Pathfinder

    Science.gov (United States)

    Farmer, Jack D.; Desmarais, David J.

    1994-01-01

    The fact that life developed on the Earth within the first billion years of its history makes it quite plausible that life may have also developed on Mars. If life did develop on Mars, it undoubtedly left behind a fossil record. Such a fossil record is likely to be more accessible than either subsurface environments that may harbor life, or scattered 'oases' that may be present at the surface. Consequently, the post-Viking approach of Mars exobiology has shifted focus to search for evidence of an ancient martian biosphere. This has led to the emergence of a new subdiscipline of paleontology, herein termed 'exopaleontology', which deals with the exploration for fossils on other planets and whose core concepts derive from Earth-based Precambrian paleontology, microbial ecology, and sedimentology. Potential targets on Mars for subaqueous spring deposits, sedimentary cements, and evaporites are ancient terminal lake basins where hydrological systems could have endured for some time under arid conditions. Potential targets for the Mars Pathfinder mission include channeled impact craters and areas of deranged drainage associated with outflows in northwest Arabia and Xanthe Terra, where water may have ponded temporarily to form lakes. The major uncertainty of such targets is their comparatively younger age and the potentially short duration of hydrological activity compared to older paleolake basins found in the southern hemisphere. However, it has been suggested that cycles of catastrophic flooding associated with Tharsis volcanism may have sustained a large body of water, Oceanus Borealis, in the northern plains area until quite late in martian history. Although problematic, the shoreline areas of the proposed northern ocean provide potential targets for a Mars Pathfinder mission aimed at exploring for carbonates or other potentially fossiliferous marine deposits. Carbonates and evaporites possess characteristic spectra signatures in the near-infrared and should be

  19. A Corrida por Terras

    Directory of Open Access Journals (Sweden)

    Paula Simas de Andrade

    2013-07-01

    Full Text Available PEARCE, Fred. The Land Grabbers - The New Fight over Who Owns the World. Boston: Beacon Press, 2012. 326 p. [Uso da terra rural, Propriedade real terras estrangeiras, propriedade Rural, investimento estrangeiro]. ISBN 978-0-8070-0324-4.

  20. Saudi Arabia.

    Science.gov (United States)

    1986-12-01

    In 1985, Saudi Arabia's population stood at 9.6 million, with an annual growth rate of 2.8%. The infant mortality rate was 78/1000 and life expectancy was 60 years. Literacy was at the 50% level among men and 25% among women. Of the work force of 3 million, 66% are foreign workers. The labor force is distributed as follows: agriculture, 14%; industry, 11%; services, commerce, and government, 53%; construction, 20%; and oil and mining, 2%. The GDP was US$98.1 billion in 1985-86, with an annual growth rate of 8% and a per capita GDP of $9800. Under the impact of rapid economic growth, urbanization has advanced rapidly and 95% of the population is now settled. Saudi Arabia, a monarchy, is divided into 14 provinces that are governed by princes or relatives of the royal family. Oil is the major source of foreign exchange, contributing 81% of government revenues. Ample government funds and foreign exchange resources are available for development, defense, and aid to other Arab and Islamic countries. The government has sought to allocate its petroleum income to transform its relatively undeveloped oil-based economy into that of a modern industrial state while maintaining traditional Islamic values. The standard of living of most Saudis has improved significantly. A shortage of skilled workers at all levels remains the principal obstacle to rapid development. PMID:12178138

  1. Nature and origin of the hematite-bearing plains of Terra Meridiani based on analyses of orbital and Mars Exploration rover data sets

    Science.gov (United States)

    Arvidson, R. E.; Poulet, F.; Morris, R.V.; Bibring, J.-P.; Bell, J.F.; Squyres, S. W.; Christensen, P.R.; Bellucci, G.; Gondet, B.; Ehlmann, B.L.; Farrand, W. H.; Fergason, R.L.; Golombeck, M.; Griffes, J.L.; Grotzinger, J.; Guinness, E.A.; Herkenhoff, K. E.; Johnson, J. R.; Klingelhofer, G.; Langevin, Y.; Ming, D.; Seelos, K.; Sullivan, R.J.; Ward, J.G.; Wiseman, S.M.; Wolff, M.J.

    2006-01-01

    The ???5 km of traverses and observations completed by the Opportunity rover from Endurance crater to the Fruitbasket outcrop show that the Meridiani plains consist of sulfate-rich sedimentary rocks that are largely covered by poorly-sorted basaltic aeolian sands and a lag of granule-sized hematitic concretions. Orbital reflectance spectra obtained by Mars Express OMEGA over this region are dominated by pyroxene, plagioclase feldspar, crystalline hematite (i.e., concretions), and nano-phase iron oxide dust signatures, consistent with Pancam and Mini-TES observations. Mo??ssbauer Spectrometer observations indicate more olivine than observed with the other instruments, consistent with preferential optical obscuration of olivine features in mixtures with pyroxene and dust. Orbital data covering bright plains located several kilometers to the south of the landing site expose a smaller areal abundance of hematite, more dust, and a larger areal extent of outcrop compared to plains proximal to the landing site. Low-albedo, low-thermal-inertia, windswept plains located several hundred kilometers to the south of the landing site are predicted from OMEGA data to have more hematite and fine-grained olivine grains exposed as compared to the landing site. Low calcium pyroxene dominates spectral signatures from the cratered highlands to the south of Opportunity. A regional-scale model is presented for the formation of the plains explored by Opportunity, based on a rising ground water table late in the Noachian Era that trapped and altered local materials and aeolian basaltic sands. Cessation of this aqueous process led to dominance of aeolian processes and formation of the current configuration of the plains. Copyright 2006 by the American Geophysical Union.

  2. NASA 3D Models: Terra

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA launched the Earth Observing System's flagship satellite Terra, named for Earth, on December 18, 1999. Terra has been collecting data about Earth's changing...

  3. Terra Harvest software architecture

    Science.gov (United States)

    Humeniuk, Dave; Klawon, Kevin

    2012-06-01

    Under the Terra Harvest Program, the DIA has the objective of developing a universal Controller for the Unattended Ground Sensor (UGS) community. The mission is to define, implement, and thoroughly document an open architecture that universally supports UGS missions, integrating disparate systems, peripherals, etc. The Controller's inherent interoperability with numerous systems enables the integration of both legacy and future UGS System (UGSS) components, while the design's open architecture supports rapid third-party development to ensure operational readiness. The successful accomplishment of these objectives by the program's Phase 3b contractors is demonstrated via integration of the companies' respective plug-'n'-play contributions that include controllers, various peripherals, such as sensors, cameras, etc., and their associated software drivers. In order to independently validate the Terra Harvest architecture, L-3 Nova Engineering, along with its partner, the University of Dayton Research Institute, is developing the Terra Harvest Open Source Environment (THOSE), a Java Virtual Machine (JVM) running on an embedded Linux Operating System. The Use Cases on which the software is developed support the full range of UGS operational scenarios such as remote sensor triggering, image capture, and data exfiltration. The Team is additionally developing an ARM microprocessor-based evaluation platform that is both energy-efficient and operationally flexible. The paper describes the overall THOSE architecture, as well as the design decisions for some of the key software components. Development process for THOSE is discussed as well.

  4. Slope Streaks in Terra Sabaea

    Science.gov (United States)

    2007-01-01

    [figure removed for brevity, see original site] Figure 1 Click on image for larger version This HiRISE image shows the rim of a crater in the region of Terra Sabaea in the northern hemisphere of Mars. The subimage (figure 1) is a close-up view of the crater rim revealing dark and light-toned slope streaks. Slope streak formation is among the few known processes currently active on Mars. While their mechanism of formation and triggering is debated, they are most commonly believed to form by downslope movement of extremely dry sand or very fine-grained dust in an almost fluidlike manner (analogous to a terrestrial snow avalanche) exposing darker underlying material. Other ideas include the triggering of slope streak formation by possible concentrations of near-surface ice or scouring of the surface by running water from aquifers intercepting slope faces, spring discharge (perhaps brines), and/or hydrothermal activity. Several of the slope streaks in the subimage, particularly the three longest darker streaks, show evidence that downslope movement is being diverted around obstacles such as large boulders. Several streaks also appear to originate at boulders or clumps of rocky material. In general, the slope streaks do not have large deposits of displaced material at their downslope ends and do not run out onto the crater floor suggesting that they have little reserve kinetic energy. The darkest slope streaks are youngest and can be seen to cross cut and superpose older and lighter-toned streaks. The lighter-toned streaks are believed to be dark streaks that have lightened with time as new dust is deposited on their surface. Observation Geometry Image PSP_001808_1875 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 15-Dec-2006. The complete image is centered at 7.4 degrees latitude, 47.0 degrees East longitude. The range to the target site was 272.1 km (170.1 miles). At this distance the

  5. EOS Terra Terra Constellation Exit/Future Maneuver Plans Update

    Science.gov (United States)

    Mantziaras, Dimitrios

    2016-01-01

    This EOS Terra Constellation Exit/Future Maneuver Plans Update presentation will discuss brief history of Terra EOM work; lifetime fuel estimates; baseline vs. proposed plan origin; resultant exit orbit; baseline vs. proposed exit plan; long term orbit altitude; revised lifetime proposal and fallback options.

  6. Geopolitical hotspots : Saudi Arabia

    International Nuclear Information System (INIS)

    This presentation reviewed the geopolitics of energy in the Middle East, with particular reference to Saudi Arabia as a potential hotspot. The author examined the question of who actually governs Saudi Arabia and the core relationship between Crown Prince Abdullah and the interior Minister, Prince Nayef. Issues regarding the country's social stability were discussed with reference to the high unemployment rate. The financial security of Saudi Arabia was also discussed with reference to the need for economic and political reform. Expectations for Saudi petroleum output were outlined along with regional spurs for energy competition and OPEC participation

  7. A hypersaline spring analogue in Manitoba, Canada for potential ancient spring deposits on Mars

    Science.gov (United States)

    Berard, Genevieve; Applin, Daniel; Cloutis, Edward; Stromberg, Jessica; Sharma, Raven; Mann, Paul; Grasby, Stephen; Bezys, Ruth; Horgan, Briony; Londry, Kathleen; Rice, Melissa; Last, Bill; Last, Fawn; Badiou, Pascal; Goldsborough, Gordon; Bell, James

    2013-06-01

    This study explores the possible applications of a spring complex, East German Creek (EGC), Manitoba, Canada, as a terrestrial analogue for similar environments on Mars. Potential ancient spring deposits have been identified by Allen and Oehler (Allen, C.C., Oehler, D.Z. [2008]. Astrobiology 8, 1093-1112) in Vernal Crater, Arabia Terra, as well as in the intercrater plains of Terra Sirenum by Wray et al. (Wray et al. [2011]. J. Geophys. Res., 116, 1-41). EGC can provide guidance in the search for fossil spring deposits on Mars by using comparative mineralogy to contrast mineral identification from field studies to that available from remote sensing instruments such as the CRISM instrument aboard the Mars Reconnaissance Orbiter. The formation processes of EGC are also useful for finding spring-like environments on Mars. A variety of techniques were employed (X-ray diffractometry, reflectance spectra, water chemistry analysis) to analyze mineralogical changes in spring water precipitates with distance from the main springs at EGC, which were compared with concentrations of dissolved species in outflow water. Biosignatures in outflow stream sediments as well as the effect of surficial Fe oxyhydroxide coatings on the detection of underlying carbonate absorption features have also been spectrally characterized. Halite is the main mineral precipitated at EGC, followed by gypsum, and calcite. The presence of gypsum is readily detected in surficial precipitate spectra while halite does not have a diagnostic spectral signature in the 0.35-2.5 μm region. An absorption feature indicative of chlorophyll a is present in stream sediment spectra from most sampling stations and on outwash plain sediments. Carbonates appear to be spectrally detectable through a coating of ferric minerals, such as goethite by a characteristic absorption band near 2.3 μm. We attempted to detect significant spectral changes over an area of potential spring features in Vernal Crater on Mars using

  8. The Seasonal Cycle of Water Vapour on Mars from Assimilation of Thermal Emission Spectrometer Data

    Science.gov (United States)

    Steele, Liam J.; Lewis, Stephen R.; Patel, Manish R.; Montmessin, Franck; Forget, Francois; Smith, Michael D.

    2014-01-01

    We present for the first time an assimilation of Thermal Emission Spectrometer (TES) water vapour column data into a Mars global climate model (MGCM). We discuss the seasonal cycle of water vapour, the processes responsible for the observed water vapour distribution, and the cross-hemispheric water transport. The assimilation scheme is shown to be robust in producing consistent reanalyses, and the global water vapour column error is reduced to around 2-4 pr micron depending on season. Wave activity is shown to play an important role in the water vapour distribution, with topographically steered flows around the Hellas and Argyre basins acting to increase transport in these regions in all seasons. At high northern latitudes, zonal wavenumber 1 and 2 stationary waves during northern summer are responsible for spreading the sublimed water vapour away from the pole. Transport by the zonal wavenumber 2 waves occurs primarily to the west of Tharsis and Arabia Terra and, combined with the effects of western boundary currents, this leads to peak water vapour column abundances here as observed by numerous spacecraft. A net transport of water to the northern hemisphere over the course of one Mars year is calculated, primarily because of the large northwards flux of water vapour which occurs during the local dust storm around L(sub S) = 240-260deg. Finally, outlying frost deposits that surround the north polar cap are shown to be important in creating the peak water vapour column abundances observed during northern summer.

  9. TERRA and the state of the telomere.

    Science.gov (United States)

    Rippe, Karsten; Luke, Brian

    2015-11-01

    Long noncoding telomeric repeat-containing RNA (TERRA) has been implicated in telomere maintenance in a telomerase-dependent and a telomerase-independent manner during replicative senescence and cancer. TERRA's proposed activities are diverse, thus making it difficult to pinpoint the critical roles that TERRA may have. We propose that TERRA orchestrates different activities at chromosome ends in a manner that depends on the state of the telomere.

  10. SUV Tracks On Mars? The 'Devil' is in the Details

    Science.gov (United States)

    1998-01-01

    Sport Utility Vehicles (SUVs) on Mars? Imagine the MOC imaging team's surprise on the morning of April 27, 1998, as the latest images came in from the 'Red Planet.'A picture taken by the camera on Mars Global Surveyor just one day earlier showed several thin, dark lines that--at first glance--looked like pathways blazed by off-road sport utility vehicles. Who's been driving around on Mars?The MOC image in question (#26403), seen here at full resolution of 13.8 meters (45 feet) per pixel, was obtained around 10:22 a.m. PDT on April 26, 1998, during Mars Global Surveyor's 264th orbit. North is approximately up, illumination is from the lower right. Located in eastern Arabia Terra near 16.5o N latitude, 311.4o W longitude, the image showed a number of natural features--small craters formed by meteor impact, several buttes and mesas left by erosion of the surrounding terrain, small dunes and drifts, and a mantle of dust that varies in thickness from place to place. But the new picture also showed two dark lines--each varying in width up to about 15 meters (49 feet)--that extended several kilometers/miles across the image.Lines like these have been seen before on Mars. They are most likely the result of dust devils--columnar vortices of wind that move across the landscape, pick up dust, and look somewhat like miniature tornadoes. Dust devils are a common occurrence in dry and desert landscapes on Earth as well as Mars. They form when the ground heats up during the day, warming the air immediately above the surface. As pockets of warm air rise and interfere with one another, they create horizontal pressure variations that, combined with other meteorological winds, cause the upward moving air to spin (the direction of the spin is controlled by the same Coriolis forces that cause terrestrial hurricanes to spin in specific directions). As the spinning column of air moves across the surface, it occasionally encounters dust on the surface, which it can suck upward. This dust

  11. Relative Ages of the Highlands, Lowlands, and Transition Zone Along a Portion of the Mars Crustal Dichotomy from Densities of Visible and Buried Impact Craters

    Science.gov (United States)

    DeSoto, G. E.; Frey, H. V.

    2005-01-01

    Understanding the fundamental age relationships of the different parts of the Mars Crustal Dichotomy is essential to fully understanding the events that shaped the early history and formation of the surface of Mars. A dominant question is what are the true relative ages of the Northern Lowlands and the Southern Highlands? Using MOLA data from the Mars Global Surveyor and Viking visual images, a dataset of both buried and visible crater diameters was created over a nine million sq km study area of a section of the dichotomy boundary stretching from Arabia Terra to Utopia Planitia. Cumulative frequency plots on a log-log scale were used to determine the relative ages for the Highlands, the Lowlands, and the Transition Zone, separately for the visible, the buried and the combined total (visible+ buried) populations. We find the overall Highland crater population in this area is slightly older than the Lowlands, consistent with previous global studies, but the Lowlands and Transition Zone are also very old and formed at roughly the same time. It appears that the formation of the Lowlands in this region formed contemporaneously with a large-scale resurfacing event in the Highlands, perhaps caused by the process responsible for the Lowland formation.

  12. TerraSAR-X mission

    Science.gov (United States)

    Werninghaus, Rolf

    2004-01-01

    The TerraSAR-X is a German national SAR- satellite system for scientific and commercial applications. It is the continuation of the scientifically and technologically successful radar missions X-SAR (1994) and SRTM (2000) and will bring the national technology developments DESA and TOPAS into operational use. The space segment of TerraSAR-X is an advanced high-resolution X-Band radar satellite. The system design is based on a sound market analysis performed by Infoterra. The TerraSAR-X features an advanced high-resolution X-Band Synthetic Aperture Radar based on the active phased array technology which allows the operation in Spotlight-, Stripmap- and ScanSAR Mode with various polarizations. It combines the ability to acquire high resolution images for detailed analysis as well as wide swath images for overview applications. In addition, experimental modes like the Dual Receive Antenna Mode allow for full-polarimetric imaging as well as along track interferometry, i.e. moving target identification. The Ground Segment is optimized for flexible response to (scientific and commercial) User requests and fast image product turn-around times. The TerraSAR-X mission will serve two main goals. The first goal is to provide the strongly supportive scientific community with multi-mode X-Band SAR data. The broad spectrum of scientific application areas include Hydrology, Geology, Climatology, Oceanography, Environmental Monitoring and Disaster Monitoring as well as Cartography (DEM Generation) and Interferometry. The second goal is the establishment of a commercial EO-market in Europe which is driven by Infoterra. The commercial goal is the development of a sustainable EO-business so that the e.g. follow-on systems can be completely financed by industry from the profit. Due to its commercial potential, the TerraSAR-X project will be implemented based on a public-private partnership with the Astrium GmbH. This paper will describe first the mission objectives as well as the

  13. Terra firma-forme dermatosis

    Directory of Open Access Journals (Sweden)

    Emel Erkek

    2012-01-01

    Full Text Available Terra firma-forme dermatosis is characterized by ′dirty′ brown-grey cutaneous patches and plaques that can simply be eradicated by forceful swabbing with alcohol pads. The pathogenesis has been attributed to abnormal and delayed keratinization. Although affected patients present with typical lesions, the disorder is not well-known by dermatologists. In this report, we describe two patients with terra firma-forme dermatosis in the setting of xerosis cutis and atopic dermatitis. From a clinical point of view, we lay emphasis on its unique expression and diagnosis/treatment. From a histological perspective, we highlight its resemblance to dermatosis neglecta and speculate on the role of ′neglect′ in a patient with seemingly adequate hygiene. The role of urea containing emollients in the development of this disorder remains to be determined.

  14. Variations in Crustal Structure, Lithospheric Flexural Strength, and Isostatic Compensation Mechanisms of Mars

    Science.gov (United States)

    Ding, M.; Lin, J.; Zuber, M. T.

    2014-12-01

    We analyze gravity and topography of Mars to investigate the spatial variations in crustal thickness, lithospheric strength, and mechanisms of support of prominent topographic features on Mars. The latest gravity model JGMRO110c (released in 2012) from the Mars Reconnaissance Orbiter mission has a spatial block size resolution of ~97 km (corresponding to degree-110), enabling us to resolve crustal structures at higher spatial resolution than those determined from previous degree-80 and 85 gravity models [Zuber et al., 2000; McGovern et al., 2002, 2004; Neumann et al., 2004; Belleguic et al., 2005]. Using the latest gravity data, we first inverted for a new version of crustal thickness model of Mars assuming homogeneous crust and mantle densities of 2.9 and 3.5 g/cm3. We calculated "isostatic" topography for the Airy local isostatic compensation mechanism, and "non-isostatic" topography after removing the isostatic part. We find that about 92% of the Martian surface is in relatively isostatic state, indicating either relatively small lithospheric strength and/or small vertical loading. Relatively isostatic regions include the hemispheric dichotomy, Hellas and Argyre Planitia, Noachis and Arabia Terra, and Terra Cimmeria. In contrast, regions with significant amount of non-isostatic topography include the Olympus, Ascraeus, Arsia, Pavonis, Alba, and Elysium Mons, Isidis Planitia and Valles Marineris. Their relatively large "non-isostatc topography" implies relatively strong lithospheric strength and large vertical loading. Spectral analysis of the admittance and correlation relationship between gravity and topography were conducted for the non-isostatic regions using the localized spectra method [Wieczorek and Simons, 2005, 2007] and thin-shell lithospheric flexural approximation [Forsyth, 1985; McGovern et al., 2002, 2004]. The best-fitting models reveal significant variations in the effective lithospheric thickness with the greatest values for the Olympus Mon

  15. The global distribution of near-surface hydrogen on Mars

    Energy Technology Data Exchange (ETDEWEB)

    Feldman, W. C. (William C.); Prettyman, T. H. (Thomas H.); Maurice, S. (Sylvestre); Bish, D. L. (David L.); Vaniman, D. T. (David T.); Squyres, Steven W.; Boynton, W. V. (William V.); Elphic, R. C. (Richard C.); Funsten, H. O. (Herbert O.); Lawrence, David J. (David Jeffery),; Tokar, R. L. (Robert L.); Moore, K. R. (Kurt R.)

    2004-01-01

    Odyssey neutron observations also revealed a near equatorial hydrogen reservoir that maximizes in Arabia Terra and its antipode. Initial quantitative estimates of hydrogen abundances in these investigations were normalized to an assumed 1% H{sub 2}O content by mass for the Viking 1 landing site. However, a recent analysis of the seasonal variation of the CO{sub 2} frost cover at the north pole has allowed an independent absolute calibration of the three neutron energy bands measured using the NS aboard Mars Odyssey. This calibration allows a reinterpretation of neutron fluxes measured globally to provide a lower bound of the hydrogen abundance within about 1 m of the Martian surface. A determination of true hydrogen abundances requires knowledge of the stratigraphy of hydrogen-bearing layers because the presence of an overlying relatively desiccated layer would mask enhanced abundances of a lower layer.

  16. Breaking new ground: digging into TERRA function.

    Science.gov (United States)

    Maicher, André; Lockhart, Arianna; Luke, Brian

    2014-05-01

    Despite the fact that telomeres carry chromatin marks typically associated with silent heterochromatin, they are actively transcribed into TElomeric Repeat containing RNA (TERRA). TERRA transcription is conserved from yeast to man, initiates in the subtelomeric region and proceeds through the telomeric tract of presumably each individual telomere. TERRA levels are increased in yeast survivors and in cancer cells employing ALT as a telomere maintenance mechanism (TMM). Thus, TERRA may be a promising biomarker and potential target in anti-cancer therapy. Interestingly, several recent publications implicate TERRA in regulatory processes including telomere end protection and the establishment of the heterochromatic state at telomeres. A picture is emerging whereby TERRA acts as a regulator of telomere length and hence the associated onset of replicative senescence in a cell. In this review we will summarize the latest results regarding TERRA transcription, localization and related function. A special focus will be set on the potential role of TERRA in the regulation of telomere length and replicative senescence. Possible implications of increased TERRA levels in yeast survivors and in ALT cancer cells will be discussed.

  17. Mars Ice Age, Simulated

    Science.gov (United States)

    2003-01-01

    December 17, 2003This simulated view shows Mars as it might have appeared during the height of a possible ice age in geologically recent time.Of all Solar System planets, Mars has the climate most like that of Earth. Both are sensitive to small changes in orbit and tilt. During a period about 2.1 million to 400,000 years ago, increased tilt of Mars' rotational axis caused increased solar heating at the poles. A new study using observations from NASA's Mars Global Surveyor and Mars Odyssey orbiters concludes that this polar warming caused mobilization of water vapor and dust into the atmosphere, and buildup of a surface deposit of ice and dust down to about 30 degrees latitude in both hemispheres. That is the equivalent of the southern Unites States or Saudi Arabia on Earth. Mars has been in an interglacial period characterized by less axial tilt for about the last 300,000 years. The ice-rich surface deposit has been degrading in the latitude zone of 30 degrees to 60 degrees as water-ice returns to the poles.In this illustration prepared for the December 18, 2003, cover of the journal Nature, the simulated surface deposit is superposed on a topography map based on altitude measurements by Global Surveyor and images from NASA's Viking orbiters of the 1970s.Mars Global Surveyor and Mars Odyssey are managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, for the NASA Office of Space Science, Washington.

  18. Terra Firma-forme Dermatosis

    Directory of Open Access Journals (Sweden)

    Anagha Ramesh Babu

    2013-01-01

    Full Text Available Terra firma-forme dermatosis is a cutaneous discoloration. ‘Dirty’ brown grey cutaneous patches and plaques that can be rid off by forceful swabbing with alcohol pads characterize it. The pathogenesis has been attributed to abnormal and delayed keratinization. It poses no medical threat. A 40-year-old male patient presented to the Department of Dermatology with a 2-3 month history of persistent pigmented patches on both upper arms. The lesions were not associated with itching or burning sensation. He gives no history of exacerbation on exposure to the sun.

  19. Telomere elongation chooses TERRA ALTernatives.

    Science.gov (United States)

    Arora, Rajika; Azzalin, Claus M

    2015-01-01

    Alternative Lengthening of Telomeres (ALT) mechanisms allow telomerase-negative immortal cells to buffer replicative telomere shortening. ALT is naturally active in a number of human cancers and might be selected upon telomerase inactivation. ALT is thought to operate through homologous recombination (HR) occurring between telomeric repeats from independent chromosome ends. Indeed, suppression of a number of HR factors impairs ALT cell proliferation. Yet, how HR is initiated at ALT telomeres remains elusive. Mounting evidence suggests that the long noncoding telomeric RNA TERRA renders ALT telomeres recombinogenic by forming RNA:DNA hybrids with the telomeric C-rich strand. TERRA and telomeric hybrids act in concert with a number of other factors, including the RNA endoribonuclease RNaseH1 and the single stranded DNA binding protein RPA. The functional interaction network built upon these different players seems indispensable for ALT telomere maintenance, and digging into the molecular details of this previously unappreciated network might open the way to novel avenues for cancer treatments.

  20. Telomere functions grounding on TERRA firma.

    Science.gov (United States)

    Azzalin, Claus M; Lingner, Joachim

    2015-01-01

    Long noncoding telomeric repeat-containing RNAs - TERRAs - are transcribed in a regulated manner from telomeres throughout eukaryotes. TERRA molecules consist of chromosome end-specific subtelomeric sequences and telomeric repeats at their 3' ends. Recent work suggests that TERRA sustains several important functions at chromosome ends. TERRA can regulate telomere length through modulation of exonuclease 1 and telomerase, it may promote recruitment of chromatin modifiers to damaged telomeres and thereby enable DNA end-processing, and it may promote telomere protein composition changes during cell cycle progression. Furthermore, telomere transcription regulates chromosome-end mobility within the nucleus. We review how TERRA, by regulated expression and by providing a molecular scaffold for various protein enzymes, can support a large variety of vital functions.

  1. Outflow channel sources, reactivation, and chaos formation, Xanthe Terra, Mars

    Science.gov (United States)

    Rodriguez, J.A.P.; Sasaki, S.; Kuzmin, R.O.; Dohm, J.M.; Tanaka, K.L.; Miyamoto, H.; Kurita, K.; Komatsu, G.; Fairen, A.G.; Ferris, J.C.

    2005-01-01

    The undulating, warped, and densely fractured surfaces of highland regions east of Valles Marineris (located north of the eastern Aureum Chaos, east of the Hydraotes Chaos, and south of the Hydaspis Chaos) resulted from extensional surface warping related to ground subsidence, caused when pressurized water confined in subterranean caverns was released to the surface. Water emanations formed crater lakes and resulted in channeling episodes involved in the excavation of Ares, Tiu, and Simud Valles of the eastern part of the circum-Chryse outflow channel system. Progressive surface subsidence and associated reduction of the subsurface cavernous volume, and/or episodes of magmatic-driven activity, led to increases of the hydrostatic pressure, resulting in reactivation of both catastrophic and non-catastrophic outflow activity. Ancient cratered highland and basin materials that underwent large-scale subsidence grade into densely fractured terrains. Collapse of rock materials in these regions resulted in the formation of chaotic terrains, which occur in and near the headwaters of the eastern circum-Chryse outflow channels. The deepest chaotic terrain in the Hydaspis Chaos region resulted from the collapse of pre-existing outflow channel floors. The release of volatiles and related collapse may have included water emanations not necessarily linked to catastrophic outflow. Basal warming related to dike intrusions, thermokarst activity involving wet sediments and/or dissected ice-enriched country rock, permafrost exposed to the atmosphere by extensional tectonism and channel incision, and/or the injection of water into porous floor material, may have enhanced outflow channel floor instability and subsequent collapse. In addition to the possible genetic linkage to outflow channel development dating back to at least the Late Noachian, clear disruption of impact craters with pristine ejecta blankets and rims, as well as preservation of fine tectonic fabrics, suggest that plateau subsidence and chaos formation may have continued well into the Amazonian Period. The geologic and paleohydrologic histories presented here have important implications, as new mechanisms for outflow channel formation and other fluvial activity are described, and new reactivation mechanisms are proposed for the origin of chaotic terrain as contributors to flooding. Detailed geomorphic analysis indicates that subterranean caverns may have been exposed during chaos formation, and thus chaotic terrains mark prime locations for future geologic, hydrologic, and possible astrobiologic exploration. ?? 2004 Elsevier Inc. All rights reserved.

  2. Hyperlipidaemia in Saudi Arabia

    International Nuclear Information System (INIS)

    Objective was to determine the prevalence of hyperlipidemia among Saudis of both genders in rural and urban communities. Selected Saudis in the age group of 30-70 years were studied over a 5-year period between 1995 and 2000 in Saudi Arabia. Data were obtained from history, physical examination and analysis of fasting plasma lipids. The data were analyzed to classify individuals with hypercholesterolemia (HC) (total cholesterol >=5.2 mmol/l) and hypertriglyceridemia (HT) (total triglycerides >=1.69 mmol/l). Logistic regression analysis was performed to provide a risk assessment model and correlation with other coronary artery disease (CAD) risk factors. The number of study samples included in the final analysis was 16,819. The prevalence of HC was 54% with mean cholesterol level of 5.4+-1.52 mmol/l. Prevalence of HC among males was 54.9% and 53.2% for females, while 53.4% among urban Saudis and 55.3% for rural Saudis. Hypertriglycemia prevalence was 40.3% with mean triglycerides level of 1.8+-1.29 mmol/l. Males had statistically significant higher HT prevalence of 47.6% compared to 33.7% in females (p<0.0001). Hyperlipidemia is reaching higher prevalence rates in KSA. This finding may suggest that CAD will soon be a major health problem. Reduction in obesity by adopting healthier eating problem habits and increasing physical activity are of considerable importance to our community. (author)

  3. First dinosaurs from Saudi Arabia.

    Directory of Open Access Journals (Sweden)

    Benjamin P Kear

    Full Text Available Dinosaur remains from the Arabian subcontinent are exceedingly rare, and those that have been documented manifest indeterminate affinities. Consequently the discovery of a small, but diagnostic, accumulation of elements from Campanian-Maastrichtian (~ 75 Ma deposits in northwestern Saudi Arabia is significant because it constitutes the first taxonomically identifiable dinosaur material described from the Arabian Peninsula. The fossils include a series of possible lithostrotian titanosaur caudal vertebrae, and some isolated theropod marginal teeth that share unique character states and metric parameters (analyzed using multivariate statistical methods with derived abelisaurids - this is the first justifiable example of a non-avian carnivorous dinosaur clade from Arabia. The recognition of titanosaurians and abelisaurids from Saudi Arabia extends the palaeogeographical range of these groups along the entire northern Gondwanan margin during the latest Cretaceous. Moreover, given the extreme paucity of coeval occurrences elsewhere, the Saudi Arabian fossils provide a tantalizing glimpse into dinosaurian assemblage diversity within the region.

  4. Saudi Arabia: petroleum industry review

    International Nuclear Information System (INIS)

    A comprehensive review is provided of Saudi Arabia's petroleum industry covering oil and gas exploration and production, refining, oil and gas trade, marketing and Saudi overseas investments. Profiles of key Saudi decision makers are provided. A statistical appendix includes data from the start of oil production in Saudi Arabia in 1938. Part I Geological potential; Part II The Saudi energy economy; Part III Production capacity; Part IV The oil refining sector ; Part V Exports and logistics; Part VI Overseas petroleum industry investments; Part VII The decision makers; Part VIII Statistical Appendix; Reserves, Production, Exports, Prices 1950 to 1999. (Author)

  5. EOS Terra: Mission Status Constellation MOWG

    Science.gov (United States)

    Mantziaras, Dimitrios

    2016-01-01

    This EOS Terra Mission Status Constellation MOWG will discuss mission summary; spacecraft subsystems summary, recent and planned activities; inclination adjust maneuvers, conjunction history, propellant usage and lifetime estimate; and end of mission plan.

  6. Adult Education in Saudi Arabia.

    Science.gov (United States)

    Griffin, Tim D.; Algren, Mark S.

    Religion pervades all aspects of Saudi Arabia, the conservative home of Islam, where the constitution is the Quran and law is interpreted by religious scholars. A formal adult basic education program was initiated in 1960. As part of the country's modernization since the early 1970s, the Saudi government has begun an enormous nation-building plan…

  7. Tectonic implications of Mars crustal magnetism.

    Science.gov (United States)

    Connerney, J E P; Acuña, M H; Ness, N F; Kletetschka, G; Mitchell, D L; Lin, R P; Reme, H

    2005-10-18

    Mars currently has no global magnetic field of internal origin but must have had one in the past, when the crust acquired intense magnetization, presumably by cooling in the presence of an Earth-like magnetic field (thermoremanent magnetization). A new map of the magnetic field of Mars, compiled by using measurements acquired at an approximately 400-km mapping altitude by the Mars Global Surveyor spacecraft, is presented here. The increased spatial resolution and sensitivity of this map provide new insight into the origin and evolution of the Mars crust. Variations in the crustal magnetic field appear in association with major faults, some previously identified in imagery and topography (Cerberus Rupes and Valles Marineris). Two parallel great faults are identified in Terra Meridiani by offset magnetic field contours. They appear similar to transform faults that occur in oceanic crust on Earth, and support the notion that the Mars crust formed during an early era of plate tectonics.

  8. Study of Aerosols’ Characteristics and Dynamics over the Kingdom of Saudi Arabia Using a Multisensor Approach Combined with Ground Observations

    Directory of Open Access Journals (Sweden)

    Ashraf Farahat

    2015-01-01

    Full Text Available This study covers various aspects of the aerosol distribution and characteristics, namely, optical depth climatology, absorption characteristics, and their microphysical properties over four regions in Saudi Arabia using satellite and ground observations including MODIS/Terra and Aqua, OMI, MISR/Terra, AERONET, and CALIPSO for the period April 2003–January 2013. The study includes cities in the North Western, Western, Eastern provinces of Saudi Arabia and in the Rub al Khali desert or Empty Quarter. Satellite and ground observations showed that the dust season extends from April to August with prominent peaks yet with high anthropogenic contribution late summer and early fall. Analysis shows an increase in the aerosol concentration during March 2009 which could be attributed to a major dust storm during that time. Comparing the AOD time series over regions 1–3 and region 4 (desert we observe monthly and annual variability with no recurrence pattern over the years. The Aqua Deep Blue AOD550 data shows a single peak pattern that occurs over region 4 during the spring season known for its frequent dust events. OMI data shed the light on the presence of higher air pollution levels over region 3, representing the oil rich eastern province of Saudi Arabia.

  9. DEMONSTRATION BULLETIN: TERRA KLEEN SOLVENT EXTRACTION TECHNOLOGY - TERRA-KLEEN RESPONSE GROUP, INC.

    Science.gov (United States)

    The Terra-Kleen Solvent Extraction Technology was developed by Terra-Kleen Response Group, Inc., to remove polychlorinated biphenyls (PCB) and other organic constituents from contaminated soil. This batch process system uses a proprietary solvent at ambient temperatures to treat ...

  10. Scaling the Pipe: NASA EOS Terra Data Systems at 10

    Science.gov (United States)

    Wolfe, Robert E.; Ramapriyan, Hampapuram K.

    2010-01-01

    Standard products from the five sensors on NASA's Earth Observing System's (EOS) Terra satellite are being used world-wide for earth science research and applications. This paper describes the evolution of the Terra data systems over the last decade in which the distributed systems that produce, archive and distribute high quality Terra data products were scaled by two orders of magnitude.

  11. Health Education in Saudi Arabia; Historical overview

    OpenAIRE

    Anwar Al-Hashem

    2016-01-01

    This article provides a historical overview of the evolution of health education in Saudi Arabia. It outlines milestones in the development of the health education profession and traces the roles of various health sectors and their achievements in the health education field. Additionally, this review seeks to describe the status of health education professionals in Saudi Arabia.

  12. Development of Higher Education in Saudi Arabia.

    Science.gov (United States)

    Saleh, Mahmoud Abdullah

    1986-01-01

    The history of higher education in Saudi Arabia is outlined, especially as it relates to Islamic religion and educational philosophy, and its rapid growth is chronicled. These aspects are examined: Saudi students studying abroad, foreign students in Saudi Arabia, women's education, the Ministry of Higher Education's role, and financing. (MSE)

  13. Urihi A: A Terra-Floresta Yanomami

    OpenAIRE

    Welch, James R.

    2010-01-01

    Review of Urihi A: A Terra-Floresta Yanomami. Bruce Albert and William Milliken with Gale Goodwin Gomez. São Paulo: Instituto Socioambiental, 2009. 207 pp., illustrations, tables, bibliography, appendices, index. Paperback ISBN: 978‐85 85994‐72‐3.

  14. Complete Genome Sequence of Gordonia terrae 3612

    Science.gov (United States)

    Russell, Daniel A.; Guerrero Bustamante, Carlos A.; Garlena, Rebecca A.

    2016-01-01

    Here, we report the complete genome sequence of Gordonia terrae 3612, also known by the strain designations ATCC 25594, NRRL B-16283, and NBRC 100016. The genome sequence reveals it to be free of prophage and clustered regularly interspaced short palindromic repeats (CRISPRs), and it is an effective host for the isolation and characterization of Gordonia bacteriophages. PMID:27688316

  15. Complete Genome Sequence of Gordonia terrae 3612.

    Science.gov (United States)

    Russell, Daniel A; Guerrero Bustamante, Carlos A; Garlena, Rebecca A; Hatfull, Graham F

    2016-01-01

    Here, we report the complete genome sequence of Gordonia terrae 3612, also known by the strain designations ATCC 25594, NRRL B-16283, and NBRC 100016. The genome sequence reveals it to be free of prophage and clustered regularly interspaced short palindromic repeats (CRISPRs), and it is an effective host for the isolation and characterization of Gordonia bacteriophages. PMID:27688316

  16. ULF fluctuations at Terra Nova Bay (Antarctica

    Directory of Open Access Journals (Sweden)

    A. Meloni

    2000-06-01

    Full Text Available ULF geomagnetic field measurements in Antarctica are a very important tool for better understanding the dynamics of the Earth’s magnetosphere and its response to the variable solar wind conditions. We review the results obtained in the last few years at the Italian observatory at Terra Nova Bay

  17. Terra Populus and DataNet Collaboration

    Science.gov (United States)

    Kugler, T.; Ruggles, S.; Fitch, C. A.; Clark, P. D.; Sobek, M.; Van Riper, D.

    2012-12-01

    Terra Populus, part of NSF's new DataNet initiative, is developing organizational and technical infrastructure to integrate, preserve, and disseminate data describing changes in the human population and environment over time. Terra Populus will incorporate large microdata and aggregate census datasets from the United States and around the world, as well as land use, land cover, climate and other environmental datasets. These data are widely dispersed, exist in a variety of data structures, have incompatible or inadequate metadata, and have incompatible geographic identifiers. Terra Populus is developing methods of integrating data from different domains and translating across data structures based on spatio-temporal linkages among data contents. The new infrastructure will enable researchers to identify and merge data from heterogeneous sources to study the relationships between human behavior and the natural world. Terra Populus will partner with data archives, data producers, and data users to create a sustainable international organization that will guarantee preservation and access over multiple decades. Terra Populus is also collaborating with the other projects in the DataNet initiative - DataONE, the DataNet Federation Consortium (DFC) and Sustainable Environment-Actionable Data (SEAD). Taken together, the four projects address aspects of the entire data lifecycle, including planning, collection, documentation, discovery, integration, curation, preservation, and collaboration; and encompass a wide range of disciplines including earth sciences, ecology, social sciences, hydrology, oceanography, and engineering. The four projects are pursuing activities to share data, tools, and expertise between pairs of projects as well as collaborating across the DataNet program on issues of cyberinfrastructure and community engagement. Topics to be addressed through program-wide collaboration include technical, organizational, and financial sustainability; semantic

  18. Euripus Mons - Landform Evolution and Climate Constraints in Promethei Terra

    Science.gov (United States)

    van Gasselt, Stephan; Kim, Jungrack; Baik, Hyun-Seob

    2016-04-01

    The Promethei Terra region of Mars exhibits a variety of geomorphic landforms indicative of ice-assisted creep of debris and ice, similar to features and processes found at the Martian dichotomy boundary in Deuteronilus, Protonilus and Nilosyrtis Mensae. Despite only little doubt about the fact that ice played an integral role in the formation of these features, it is still disputed if these features were formed by glacial processes, requiring precipitation of ice and snow and exhibiting glacial deformation and basal sliding, or if these landforms are a product of periglacial denudation and subject to different deformation regimes. As information about past climate conditions on Mars is sparse, the proper assessment of landform types today allows to put constraints on their environmental conditions in the past. Due to limited knowledge about the internal physical and thermal structure of these landforms, it remains impossible to unambiguously determine their origin [1]. A variety of geomorphic and model-based indicators need to be taken into account when putting constraints on their history and when trying to reconstruct their evolution. For selected features on Mars it has been shown by SHARAD radar observations that the ice content might be relatively high [2], and that some of them might be composed of pure ice, protected from sublimation by a thin debris cover. One of such examples, Euripus Mons, is a 80 km remnant feature with an associated circumferential talus deposit that shows indicators for deformation by downslope movement, i.e. debris apron morphology. Recent modelling assuming glacial deformation helped to reconstruct some internal structural properties [3]. Despite these attempts, Euripus Mons shows clear geomorphic signatures of classical periglacial denudation which do not fit into the concept of glacial-only evolution. Denudation rates as well as ages are similar to those reported from other locations on Mars for which hyperarid climate conditions

  19. Levantamento de cafèzais do Estado de São Paulo pela análise química foliar II: Solos Podzolizados de Lins e Marília, Latossolo Roxo e Podzólico Vermelho Amarelo-Orto Survey of the nutritional condition of the coffee in the State of São Paulo through foliar analyses: II - Podzolized soils of Lins and Marilia, Latosolic B "Terra Roxa" and Ortho-Red Yellow Podzol

    Directory of Open Access Journals (Sweden)

    J. Romano Gallo

    1970-01-01

    Full Text Available Em amostras de 134 cafèzais, distribuídos nos principais grupos de solos do Estado de São Paulo, colhidas em três estações do ano, foram determinados 12 elementos químicos essenciais, sódio e alumínio. A percentagem de cafèzais deficientes em nitrogênio foi superior a 80% em todos os solos. No Podzolizado de Lins e Marília, o segundo elemento em falta foi o ferro. No Latossolo Roxo, depois do nitrogênio, a maior deficiência foi a de potássio e zinco; no Podzólico Vermelho Amarelo-Orto, a de boro.Roughly, coffee fields are distributed on. the main types of soil in the State of São Paulo as follows: Podzolized Soils of Lins and Marilia, 70%; latosolic B "Terra Roxa", 15%; Ortho-Red Yellow Podzol, 10%; other types, 5%. This paper presents and discusses data on foliar analyses of coffee, plants cultivated on the 3 first soil types. It complements a previous survey made on red-yellow ortho podzol. Leaf samples were collected in the spring, summer and fall, from 134 "Mundo Novo" coffee fields. Besides the content of 12 essential elements, amount of Na and Al were also determined in these samples. Fe, Zn, Mn, and Cu were determined by atomic absorption spectrophotometry. The first 3 elements were determined in a wet digest of 0.5 g of dry plant material with a mixture of HNO3-H2SO4-HC10(4, in a final volume of 20 ml. Determination of Cu, on the other hand, required an extract obtained by dissolving in 10 ml of 0.25N HC1, ashes from 1.25 g of dry leaf tissue, incinerated at 500°C for 2 hours. The same extract used for Fe, Zn and Mn analyses served for Na and Al determination. However, content of Al was estimated by colorimetric method of Aluminon (1 whereas amount of Na was determined by flame emission photometry (2. The remaining elements - N, P, K, Ca Mg, S-S0(4, B and Mo - were determined according to the process described by Lott et al (4, 5. Evaluation of the nutritional condition of the coffee fields in each soil type was based

  20. Saudi Arabia plans future strategy

    International Nuclear Information System (INIS)

    The future strategy of Saudi Arabia with respect to its oil production capacity is discussed. A major uncertainty affecting planning is the prospect of an Iraqi return to the market as and when Saddam Hussein falls or he manages to comply fully with all the UN resolutions and sanctions are lifted. It is believed that Iraq could at very short notice be capable of exporting 2mb/d of crude rising to 2.5 mb/d within a few months. This is 10% of OPEC's physically traded crude. Also taken seriously are Baghdad's assertions that Iraq will have a production capacity of about 6mb/d by the year 2000. Saudi officials are concerned that OPEC is not ready to tackle the impact of an Iraqi return to the market at a time when some OPEC members are producing above quota anyway. The most likely outcome is thought to be that OPEC would simply raise their nominal production ceiling. Against this background, Saudi Arabia has embarked on the exploitation of the gigantic oil reserves of the Shaybah field. This development offers the kingdom an ability, on the one hand, to increase its earnings while remaining within its OPEC quota and, on the other hand, to increase output substantially should it ever appear that its best interests are served by not adhering to quotas. (UK)

  1. Volatile-rich Crater Interior Deposits on Mars: An Energy Balance Model of Modification

    Science.gov (United States)

    Russell, Patrick S.; Head, James W.; Hecht, Michael H.

    2003-01-01

    Several craters on Mars are partially filled by material emplaced by post-impact processes. Populations of such craters include those in the circumsouth polar cap region, in Arabia Terra, associated with the Medusae Fossae Formation, and in the northern lowlands proximal to the north polar cap. In this study, crater fill material refers to an interior mound, generally separated from the interior walls of the crater by a trough that may be continuous along the crater s circumference (i.e. a ring-shaped trough), or may only partially contact the crater walls (i.e. a crescent-shaped trough). The fill deposit is frequently off-center from the crater center and may be asymmetric, (i.e. not circular) in plan view shape. Here we test the hypothesis that asymmetries in volatile fill shape, profile, and center-location within a crater result from asymmetries in local energy balance within the crater due mainly to variation of solar insolation and radiative effects of the crater walls over the crater interior. We first focus on Korolev crater in the northern lowlands. We can then apply this model to other craters in different regions. If asymmetry in morphology and location of crater fill are consistent with radiative-dominated asymmetries in energy budget within the crater, then 1) the volatile-rich composition of the fill is supported (this process should not be effective at shaping volcanic or sedimentary deposits), and 2) the dominant factor determining the observed shape of volatile-rich crater fill is the local radiative energy budget within the crater (and erosive processes such as eolian deflation are not necessary).

  2. Saudi Arabia: persistent but tenable deficits

    International Nuclear Information System (INIS)

    In this article is described the economic situation of Saudi Arabia. In a first time, Saudi Arabia drew from external reserves to finance gulf war and covered its budget deficits, then the internal debts took over. The actual strategy in order to transfer from state to private national and foreign sector a great part of new projects financing is become a necessity to control the deficits in a country where state is strongly got in debt. (N.C.). 2 tabs

  3. FACTORS AFFECTING RICE CONSUMPTION IN SAUDI ARABIA

    OpenAIRE

    Duwais, Abdul-Aziz M.

    1983-01-01

    During the past decade, the Kingdom of Saudi Arabia has undergone rapid economic growth and development. This expansion stems from the increase in the Kingdom's production of petroleum--oil being the source of most of the country's exports, foreign exchange, and government revenues. However, despite this growth, Saudi Arabia is one of the top foodstuff importers among developing countries. It has been estimated that the value of Saudi agriculture imports in 1981 increased about 33 percent to ...

  4. Terra Mission Operations: Launch to the Present (and Beyond)

    Science.gov (United States)

    Kelly, Angelita; Moyer, Eric; Mantziaras, Dimitrios; Case, Warren

    2014-01-01

    The Terra satellite, flagship of NASA's long-term Earth Observing System (EOS) Program, continues to provide useful earth science observations well past its 5-year design lifetime. This paper describes the evolution of Terra operations, including challenges and successes and the steps taken to preserve science requirements and prolong spacecraft life. Working cooperatively with the Terra science and instrument teams, including NASA's international partners, the mission operations team has successfully kept the Terra operating continuously, resolving challenges and adjusting operations as needed. Terra retains all of its observing capabilities (except Short Wave Infrared) despite its age. The paper also describes concepts for future operations. This paper will review the Terra spacecraft mission successes and unique spacecraft component designs that provided significant benefits extending mission life and science. In addition, it discusses special activities as well as anomalies and corresponding recovery efforts. Lastly, it discusses future plans for continued operations.

  5. Mars bevares

    DEFF Research Database (Denmark)

    Hendricks, Vincent Fella; Hendricks, Elbert

    2009-01-01

    2009 er femåret for Mission Mars. I den anledning opridser de to kronikører, far og søn, hvorfor man bør lade planer om en bemandet tur til Mars forblive i skrivebordsskuffen......2009 er femåret for Mission Mars. I den anledning opridser de to kronikører, far og søn, hvorfor man bør lade planer om en bemandet tur til Mars forblive i skrivebordsskuffen...

  6. Celebrating Saudi Arabia: Using the Five Fundamental Themes of Geography in Order to Discover Saudi Arabia

    Science.gov (United States)

    Fitzhugh, William

    2006-01-01

    The Kingdom of Saudi Arabia is a large Arab, Muslim country in the Middle East. It has been an economic and political partner of the United States for many years. This unit, designed for elementary students, provides a text, questions, mapping skills, and fun activities. Students read about Saudi Arabia to gain insights and an appreciation of…

  7. Mars Mission

    OpenAIRE

    2004-01-01

    This interactive exercise allows students to test their knowledge of orbital mechanics by sending a rocket to Mars. They will have to estimate the time in space, the phase between earth and Mars at the time the rocket is launched, and the initial speed of the rocket. PH2151 Particle Mechanics

  8. Results of Statewide TerraNova Testing, Fall 1998.

    Science.gov (United States)

    La Marca, Paul M.

    This summary provides key findings about state, district, and school level performance on the TerraNova examinations (CTB/McGraw Hill) in Nevada in 1998-1999. The TerraNova tests are used to assess students in grades 4, 8, and 10 as stipulated by Nevada law. Within this summary, a description of performance as measured by national percentile…

  9. Genomic Organization and Expression in E. coli of Zebrafish Terra

    Institute of Scientific and Technical Information of China (English)

    赵知行; 华正春; 孟安明

    2001-01-01

    Zebrafish terra encodes a transcription factor that is specifically expressed in developing somites.Previous studies suggested that this gene is involved in vertebrate somitogenesis. In this study, the genomic DNA of terra locus was isolated and its organization was investigated. The analysis showed that terra locus consists of 3 introns and occupies 3154 bp in the genome of zebrafish. The exon-intron junctions of the second and third introns conform to the GT-AG rule, while the first intron has the unusual junction sequences of GT-AC. An IPTG-inducible expression system was established to produce terra protein in bacterial cells. Overexpression of terra protein leads to the formation of inclusion bodies in the bacterial ceils. The protein will be used to study its structure and function.

  10. Role of TERRA in the regulation of telomere length.

    Science.gov (United States)

    Wang, Caiqin; Zhao, Li; Lu, Shiming

    2015-01-01

    Telomere dysfunction is closely associated with human diseases such as cancer and ageing. Inappropriate changes in telomere length and/or structure result in telomere dysfunction. Telomeres have been considered to be transcriptionally silent, but it was recently demonstrated that mammalian telomeres are transcribed into telomeric repeat-containing RNA (TERRA). TERRA, a long non-coding RNA, participates in the regulation of telomere length, telomerase activity and heterochromatinization. The correct regulation of telomere length may be crucial to telomeric homeostasis and functions. Here, we summarize recent advances in our understanding of the crucial role of TERRA in the maintenance of telomere length, with focus on the variety of mechanisms by which TERRA is involved in the regulation of telomere length. This review aims to enable further understanding of how TERRA-targeted drugs can target telomere-related diseases.

  11. Saudi Arabia and CERN sign protocol

    CERN Multimedia

    2008-01-01

    On 9 May 2008, Mohammed I. Al Suwaiyel, President of the King Abdulaziz City of Science and Technology, representing the Government of Saudi Arabia, and CERN Director-General, Robert Aymar, signed a protocol to the 2006 cooperation agreement between CERN and Saudi Arabia. Members of the Saudi Arabian Government visit ATLAS.The purpose of the protocol is to define the operational framework needed to carry out various specific tasks provided for in the cooperation agreement in order to promote the development of a high energy particle physics community in Saudi Arabia and its ultimate visible participation as a member of the global CERN community. Signing the protocol, Mohammed I. Al-Suwaiyel said: "The Saudi Arabian Government has taken a number of initiatives to promote R&D in the interests of our country’s development and the advancement of science. Thanks to this protocol, Saudi scientists will be able to work towards this go...

  12. Sustainable Energy Development in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Mounir Belloumi

    2015-04-01

    Full Text Available The main objective of this research is to study the role of energy consumption in economic growth in Saudi Arabia over the period of 1971–2012 using the autoregressive distributed lag (ARDL cointegration procedure, and based on neoclassical growth, endogenous growth, and ecological-economics viewpoints. Our empirical results show the existence of a cointegrating relationship between the different variables investigated. In addition, all the inputs (conventional and non-conventional Granger cause economic growth in both the short and long runs. Our findings confirm the energy-led growth hypothesis in the case of Saudi Arabia. Hence, energy conservation policies may deteriorate economic growth in Saudi Arabia if they are not followed by measures that improve energy efficiency, energy saving technologies and encourage the investment and use of renewable energy sources such as solar and wind energies that can participate in the attenuation of climate changes.

  13. Mars Pathfinder

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    First of NASA's Discovery missions. Launched in December 1996 and arrived at Mars on 4 July 1997. Mainly intended as a technology demonstration mission. Used airbags to cushion the landing on Mars. The Carl Sagan Memorial station returned images of an ancient flood plain in Ares Vallis. The 10 kg Sojourner rover used an x-ray spectrometer to study the composition of rocks and travelled about 100 ...

  14. Exploring Mars

    Science.gov (United States)

    Breuil, Stéphanie

    2016-04-01

    Mars is our neighbour planet and has always fascinated humans as it has been seen as a potential abode for life. Knowledge about Mars is huge and was constructed step by step through numerous missions. It could be difficult to describe these missions, the associated technology, the results, the questions they raise, that's why an activity is proposed, that directly interests students. Their production is presented in the poster. Step 1: The main Mars feature and the first Mars explorations using telescope are presented to students. It should be really interesting to present "Mars Canals" from Percival Lowell as it should also warn students against flawed interpretation. Moreover, this study has raised the big question about extra-terrestrial life on Mars for the first time. Using Google Mars is then a good way to show the huge knowledge we have on the planet and to introduce modern missions. Step 2: Students have to choose and describe one of the Mars mission from ESA and NASA. They should work in pairs. Web sites from ESA and NASA are available and the teacher makes sure the main missions will be studied. Step 3: Students have to collect different pieces of information about the mission - When? Which technology? What were the main results? What type of questions does it raise? They prepare an oral presentation in the form they want (role play, academic presentation, using a poster, PowerPoint). They also have to produce playing cards about the mission that could be put on a timeline. Step 4: As a conclusion, the different cards concerning different missions are mixed. Groups of students receive cards and they have to put them on a timeline as fast as possible. It is also possible to play the game "timeline".

  15. Mars resources

    Science.gov (United States)

    Duke, Michael B.

    1986-01-01

    The most important resources of Mars for the early exploration phase will be oxygen and water, derived from the Martian atmosphere and regolith, which will be used for propellant and life support. Rocks and soils may be used in unprocessed form as shielding materials for habitats, or in minimally processed form to expand habitable living and work space. Resources necessary to conduct manufacturing and agricultural projects are potentially available, but will await advanced stages of Mars habitation before they are utilized.

  16. Terra Foundation for American Art Europe

    Directory of Open Access Journals (Sweden)

    Géraldine Chouard

    2009-07-01

    Full Text Available Le 25 novembre 2008, à l'INHA, l'équipe de la Terra Foundation for American Art a annoncé ses nouveaux projets et notamment, à la suite de la fermeture du Musée d’art américain de Giverny, la création d'un centre parisien, situé dans le 2è arrondissement. Ce centre souhaite être, pour tous ceux que l'art américain intéresse, un nouveau lieu de ressources, d'échanges et de contacts.Sophie Lévy, Veerle Thielemans, Katherine Bourguignon, Ewa Bobrowska, Francesca Rose et Véronique Bossard ont tou...

  17. Mars crustal magnetism, plate tectonics, and more

    Science.gov (United States)

    Connerney, J.; Acuna, M.; Ness, N.

    Mars has no global magnetic field of internal origin, but must have had one in the past when the crust acquired intense magnetization, presumably by cooling in the presence of an Earth-like magnetic field (thermoremanent magnetization or TRM). The Mars crust is at least an order of magnitude more intensely magnetized than that of the Earth. The apparent lack of magnetization associated with major impact basins suggests that the crust acquired magnetic remanence early in its history, about 4 billion years ago. A new map of the magnetic field of Mars, compiled at ˜ 400 km mapping altitude by Mars Global Surveyor, is presented here. The spatial resolution and sensitivity of this global map is unprecedented, inviting geologic interpretation heretofor reserved for aeromagnetic and ship surveys on Earth. These data provide new insight into the origin and evolution of the Mars crust. The apparent lack of magnetization associated with volcanic provinces may indicate that the magnetic layer resides within a few km of the surface, requiring magnetization intensity of order few 100 A/m, almost unthinkable. Two parallel great faults are identified in Terra Meridiani by offset magnetic field contours. They appear similar to transform faults that occur in oceanic crust on Earth, and describe the relative motion of two ancient Mars plates on the surface of a sphere. The magnetic imprint in Meridiani is consistent with that observed above a mid-ocean ridge on Earth. It is a relic of an era of plate tectonics on Mars, an era of crustal spreading, rifting, plate motions, and widespread volcanism following the demise of the dynamo. We present this new data in the context of the early development of plate tectonics on Earth, as advanced by the Vine-Matthews hypothesis and the work of W. Jason Morgan and others. Finally, we discuss the next logical steps in Mars exploration: magnetic surveys on global and regional scales.

  18. History and Technology of Terra Preta Sanitation

    Directory of Open Access Journals (Sweden)

    Sabino De Gisi

    2014-03-01

    Full Text Available In order to reach the Millennium Development Goals for significantly reducing the number of people without access to adequate sanitation, new holistic concepts are needed focusing on economically feasible closed-loop ecological sanitation systems rather than on expensive end-of-pipe technologies. An analysis of a former civilization in the Amazon (nowadays Brazil highlights the possibility to close the loop with a more sustainable lifestyle integrating soil fertility, food security, waste management, water protection and sanitation, renewable energy. Terra Preta do Indio is the anthropogenic black soil produced by ancient cultures through the conversion of bio-waste, fecal matter and charcoal into long-term fertile soils. These soils have maintained high amounts of organic carbon several thousand years after they were abandoned. Deriving from these concepts, Terra Preta Sanitation (TPS has been re-developed and adopted. TPS includes urine diversion, addition of a charcoal mixture and is based on lactic-acid-fermentation with subsequent vermicomposting. Lacto-fermentation is a biological anaerobic process that generates a pre-stabilization of the mixture. The main advantage of lacto-fermentation is that no gas and no odor is produced. What makes it particularly interesting for in-house systems even in urban areas. Instead, vermicomposting is an aerobic decomposition process of the pre-digested materials by the combined action of earthworms and microorganisms. It transforms the carbon and nutrients into the deep black, fertile and stable soil that can be utilized in agriculture. No water, ventilation or external energy is required. Starting from ancient Amazonian civilizations traditional knowledge, the aim of this work is to present TPS systems adopted nowadays.

  19. TERRA NEWS: Sensationalism and Fait-divers on the Internet

    OpenAIRE

    Carlos Golembiewski; Diógenes Pandini

    2009-01-01

    This article presents an analysis of the news program Jornal do Terra (Terra News) shown on the Terra website. The study involved two aspects: forms of news presentations on TV, based on studies by Pedro Maciel, and criteria of news value, based on Mário Erbolatto’s view. In addition, we used Luis Arthur Ferraretto’s studies of the news formats used specifically on the radio. The objective of this work was to verify what kind of news is transmitted by the news p...

  20. Alkhurma Hemorrhagic Fever in Saudi Arabia

    Centers for Disease Control (CDC) Podcasts

    2010-10-28

    This podcast looks at the epidemiologic characteristics of Alkhurma Hemorrhagic Fever in humans in Najran City, Saudi Arabia. CDC epidemiologist Dr. Adam MacNeil discusses the severity and risk factors for the illness.  Created: 10/28/2010 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 11/17/2010.

  1. Cenozoic volcanic rocks of Saudi Arabia

    Science.gov (United States)

    Coleman, R.G.; Gregory, R.T.; Brown, G.F.

    2016-01-01

    The Cenozoic volcanic rocks of Saudi Arabia cover about 90,000 km2, one of the largest areas of alkali olivine basalt in the world. These volcanic rocks are in 13 separate fields near the eastern coast of the Red Sea and in the western Arabian Peninsula highlands from Syria southward to the Yemen Arab Republic.

  2. Saudi Arabia between conservatism, accomodation and reform

    NARCIS (Netherlands)

    R. Meijer; P. Aarts; J. Wagemakers; M. Kanie; A. Geel

    2012-01-01

    Of all the countries in the Middle East, Saudi Arabia seems to have remained immovable since the beginning of the Arab Spring. What does conservatism mean, are reforms possible, and what is the pace of change? The clever mix of conservatism, reform and accommodation are the characteristic features o

  3. Online Continuing Medical Education in Saudi Arabia

    Science.gov (United States)

    Alwadie, Adnan D.

    2013-01-01

    As the largest country in the Middle East, Saudi Arabia and its health care system are well positioned to embark on an online learning intervention so that health care providers in all areas of the country have the resources for updating their professional knowledge and skills. After a brief introduction, online continuing medical education is…

  4. The Education of Women in Saudi Arabia.

    Science.gov (United States)

    Al Rawaf, Haya Saad; Simmons, Cyril

    1991-01-01

    Describes the development and expansion of formal education for women in Saudi Arabia since 1960. Discusses girls' curriculum in elementary and secondary schools, the influence of conservative attitudes toward sex roles, and the growth of female higher education despite a lack of female employment. Contains 20 references. (SV)

  5. Effect of MODIS Terra Radiometric Calibration Improvements on Collection 6 Deep Blue Aerosol Products: Validation and Terra/Aqua Consistency

    Science.gov (United States)

    Sayer, A. M.; Hsu, N. C.; Bettenhausen, C.; Jeong, M.-J.; Meister, G.

    2015-01-01

    The Deep Blue (DB) algorithm's primary data product is midvisible aerosol optical depth (AOD). DB applied to Moderate Resolution Imaging Spectroradiometer (MODIS) measurements provides a data record since early 2000 for MODIS Terra and mid-2002 for MODIS Aqua. In the previous data version (Collection 5, C5), DB production from Terra was halted in 2007 due to sensor degradation; the new Collection 6 (C6) has both improved science algorithms and sensor radiometric calibration. This includes additional calibration corrections developed by the Ocean Biology Processing Group to address MODIS Terra's gain, polarization sensitivity, and detector response versus scan angle, meaning DB can now be applied to the whole Terra record. Through validation with Aerosol Robotic Network (AERONET) data, it is shown that the C6 DB Terra AOD quality is stable throughout the mission to date. Compared to the C5 calibration, in recent years the RMS error compared to AERONET is smaller by approximately 0.04 over bright (e.g., desert) and approximately 0.01-0.02 over darker (e.g., vegetated) land surfaces, and the fraction of points in agreement with AERONET within expected retrieval uncertainty higher by approximately 10% and approximately 5%, respectively. Comparisons to the Aqua C6 time series reveal a high level of correspondence between the two MODIS DB data records, with a small positive (Terra-Aqua) average AOD offset Terra DB AOD data remain stable (to better than 0.01 AOD) throughout the mission to date, suitable for quantitative scientific analyses.

  6. Career profile of dentists in Saudi Arabia

    International Nuclear Information System (INIS)

    The aims of the present survey were to determine whether differences existed between male and female dentists in Saudi Arabia in career development, positions occupied within their employment, and to analyze the effect of different variables on their career development in some of the provinces in Saudi Arabia. A self-conducted questionnaire was distributed among male and female dentists, general practitioners as well as specialists, working at several governmental hospitals in Saudi Arabia. The questionnaires consisted of 40 questions in the format of multiple choices and yes/no answer. Data were analyzed by gender with the significant difference level set at (P < 0.05). The response rate was 40.8% of which 51.9% were females and 48.1% males with 70% of them below 45 years of age. No significant difference was found between males and females in having higher education or additional degrees. The specialty that was highly reported among females was pedodontics and in males, orthodontics. Males were more likely to hold authorized administrative positions (63%), while females held administrative positions which were internally arranged by their departments (57%). Eighty-three percent of female respondents thought that there was favouritism towards males in appointment to administrative positions, while only 5.5% of male respondents reported that there was favouritism to females in occupying the same positions. There was no significant difference between male and female dentists in Saudi Arabia with respect to job opportunities, working hours and relationships with their colleagues. In addition, there is evidence of an intensifying determination of female dentists in Saudi Arabia, to pursue their chosen career while coping with the diverse demands of being a professional, a wife and mother. (author)

  7. Identification of chromatin marks at TERRA promoter and encoding region.

    Science.gov (United States)

    Negishi, Yutaka; Kawaji, Hideya; Minoda, Aki; Usui, Kengo

    2015-11-27

    TERRA is a long non-coding RNA that is essential for telomere integrity. Although it is transcribed from subtelomeres and telomeres, how it is expressed in heterochromatic region is currently unknown. In this study, we focused our analysis on TERRA-encoding region TelBam3.4 and TelBam3.4-like sequences, and determined their transcription start sites, as well as enrichment of RNA polymerase II and histone modifications. We found that H3K4me3 and H3K9me3 are present at TERRA promoters, whereas H3K27ac and H3K9me3 are present at telomeric repeats. Consistently, we show that presence of active histone modifications H3K4me3 and H3K27ac are correlated to TERRA expression. These results mark an important step towards understanding telomere maintenance and transcription.

  8. Completion and Submission of the Terra Sirenum Map Project

    Science.gov (United States)

    Anderson, R. C.; Dohm, J. M.; Robbins, S.; Schroeder, J.

    2016-06-01

    We have completed and plan to submit a detailed 1:5,000,000-scale geologic map of the Terra Sirenum region, which includes mapping stratigraphic units and identifying tectonic, erosional, depositional, and impact structures.

  9. TERRA promotes telomerase-mediated telomere elongation in Schizosaccharomyces pombe.

    Science.gov (United States)

    Moravec, Martin; Wischnewski, Harry; Bah, Amadou; Hu, Yan; Liu, Na; Lafranchi, Lorenzo; King, Megan C; Azzalin, Claus M

    2016-07-01

    Telomerase-mediated telomere elongation provides cell populations with the ability to proliferate indefinitely. Telomerase is capable of recognizing and extending the shortest telomeres in cells; nevertheless, how this mechanism is executed remains unclear. Here, we show that, in the fission yeast Schizosaccharomyces pombe, shortened telomeres are highly transcribed into the evolutionarily conserved long noncoding RNA TERRA A fraction of TERRA produced upon telomere shortening is polyadenylated and largely devoid of telomeric repeats, and furthermore, telomerase physically interacts with this polyadenylated TERRA in vivo We also show that experimentally enhanced transcription of a manipulated telomere promotes its association with telomerase and concomitant elongation. Our data represent the first direct evidence that TERRA stimulates telomerase recruitment and activity at chromosome ends in an organism with human-like telomeres.

  10. TerraService.NET: An Introduction to Web Services

    OpenAIRE

    Barclay, Tom; Gray, Jim; Strand, Eric; Ekblad, Steve; Richter, Jeffrey

    2002-01-01

    This article explores the design and construction of a geo-spatial Internet web service application from the host web site perspective and from the perspective of an application using the web service. The TerraService.NET web service was added to the popular TerraServer database and web site with no major structural changes to the database. The article discusses web service design, implementation, and deployment concepts and design guidelines. Web services enable applications that aggregate a...

  11. Functional characterization of the TERRA transcriptome at damaged telomeres.

    Science.gov (United States)

    Porro, Antonio; Feuerhahn, Sascha; Delafontaine, Julien; Riethman, Harold; Rougemont, Jacques; Lingner, Joachim

    2014-01-01

    Telomere deprotection occurs during tumorigenesis and aging upon telomere shortening or loss of the telomeric shelterin component TRF2. Deprotected telomeres undergo changes in chromatin structure and elicit a DNA damage response (DDR) that leads to cellular senescence. The telomeric long noncoding RNA TERRA has been implicated in modulating the structure and processing of deprotected telomeres. Here, we characterize the human TERRA transcriptome at normal and TRF2-depleted telomeres and demonstrate that TERRA upregulation is occurring upon depletion of TRF2 at all transcribed telomeres. TRF2 represses TERRA transcription through its homodimerization domain, which was previously shown to induce chromatin compaction and to prevent the early steps of DDR activation. We show that TERRA associates with SUV39H1 H3K9 histone methyltransferase, which promotes accumulation of H3K9me3 at damaged telomeres and end-to-end fusions. Altogether our data elucidate the TERRA landscape and defines critical roles for this RNA in the telomeric DNA damage response.

  12. FACTORS AFFECTING THE IMPORT OF WHEAT IN SAUDI ARABIA

    OpenAIRE

    Al-Goosi, Adbullah I.

    1980-01-01

    The modern economy of Saudi Arabia depends primarily on oil exports. Oil being the source of most of the country's exports, foreign exchange, and government revenues, it follows that the oil sector affects the economy rather than the economy affecting the oil sector. Saudi Arabia lacks natural resources for most of its essential goods and because of sudden high income, it has become necessary to introduce new strategies for producing necessary goods and services. Since Saudi Arabia depends mo...

  13. Peaceful nuclear energy to Saudi Arabia

    International Nuclear Information System (INIS)

    The argument for and against the application of peaceful nuclear energy in Saudi Arabia is discussed in terms of the country's industrial development and power requirement for electricity and desalination. The discussion leads to the conclusion that due to its large oil reserve, Saudi Arabia may tolerate a considerate approach to nuclear energy up to the year 2000. Beyond this date, nuclear energy should be used in order to achieve the desired industrial maturity in the country. The introduction of nuclear energy, however, will be faced with three constraints, namely man power availability, cooling water requirement, and the size of the electrical grid. The period 1980-2000 is thus most suitable for important preparation steps, among which are the adoption of regulatory provisions, establishment of nuclear facilities with necessary equipments, and staff training for regulatory, organizational, and technical activities. The paper outlines a scheme for the initiation steps and efforts to meet these requirements. (orig.)

  14. Solar Power Potential In Saudi Arabia

    Directory of Open Access Journals (Sweden)

    F. R. Pazheri

    2014-09-01

    Full Text Available The expansion of power generation in Saudi Arabia is essential in order to meet the expected growth of its electricity demand. Due to the availability of high solar irradiation, vast rainless area and longtime sun light, Saudi Arabia is one of the most suitable countries to utilize solar energy resources in greater extend. Kingdom has planned to increase the production of solar power in order to meet a considerable share of country’s future energy demand. Numerous installation and research works are going on nowadays in the kingdom in order to attain its targets of solar power capacity in the coming years. Hence latest updates of country’s solar industry are essential for further research and R&D works in this field. Saudi Arabia’s current status and future possibility of solar industry are discussed in this paper.

  15. Core inflation indicators for Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Alkhareif Ryadh M.

    2015-01-01

    Full Text Available This paper constructs and analyzes core inflation indicators for Saudi Arabia for the period of March 2012 to May 2014 using two alternative approaches: the exclusion method (ex food and housing/rent and the statistical method. The findings of the analysis suggest that the ex food and housing/ rent inflation is more volatile than the overall CPI inflation over the sample period. In contrast, the statistical core inflation is relatively more stable and less volatile. Moreover, the ex food and housing/rent inflation is only weakly correlated with headline inflation, whereas the statistical core inflation exhibits a stronger correlation. This combination of lower volatility and higher correlation with headline inflation makes the statistical method a much better choice for policymakers. From a monetary policy standpoint, using a bundle of core inflation measures, including both properly constructed exclusion and statistical methods, is more desirable, especially when variation across measures is widespread, as is the case in Saudi Arabia.

  16. ERP Implementation Success Factors in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Malik F. Saleh

    2013-04-01

    Full Text Available A review of the literature on successful implementation of ERP reveals that there are many case studies undertaken by researches, but very few have empirically examined the success factors of ERP implementation. While most of those empirical studies were undertaken in Western countries, very few had examined the implementations in Middle Eastern countries and none in Saudi Arabia. Factors and challenges of ERP implementation in developing countries differ from those of Western countries. Hence a gap in the literature that examines Middle Eastern countries exists. This study is motivated to fill such gap by going beyond case study and boundaries of Western counties to empirically examine the determinants of successful ERP implementation in Saudi Arabia. The main purpose of this study is to examine the influence of some critical factors on successful implementation of ERP.

  17. Telomeric repeat-containing RNA (TERRA) constitutes a nucleoprotein component of extracellular inflammatory exosomes

    Science.gov (United States)

    Wang, Zhuo; Deng, Zhong; Dahmane, Nadia; Tsai, Kevin; Wang, Pu; Williams, Dewight R.; Kossenkov, Andrew V.; Showe, Louise C.; Zhang, Rugang; Huang, Qihong; Conejo-Garcia, José R.; Lieberman, Paul M.

    2015-01-01

    Telomeric repeat-containing RNA (TERRA) has been identified as a telomere-associated regulator of chromosome end protection. Here, we report that TERRA can also be found in extracellular fractions that stimulate innate immune signaling. We identified extracellular forms of TERRA in mouse tumor and embryonic brain tissue, as well as in human tissue culture cell lines using RNA in situ hybridization. RNA-seq analyses revealed TERRA to be among the most highly represented transcripts in extracellular fractions derived from both normal and cancer patient blood plasma. Cell-free TERRA (cfTERRA) could be isolated from the exosome fractions derived from human lymphoblastoid cell line (LCL) culture media. cfTERRA is a shorter form (∼200 nt) of cellular TERRA and copurifies with CD63- and CD83-positive exosome vesicles that could be visualized by cyro-electron microscopy. These fractions were also enriched for histone proteins that physically associate with TERRA in extracellular ChIP assays. Incubation of cfTERRA-containing exosomes with peripheral blood mononuclear cells stimulated transcription of several inflammatory cytokine genes, including TNFα, IL6, and C-X-C chemokine 10 (CXCL10) Exosomes engineered with elevated TERRA or liposomes with synthetic TERRA further stimulated inflammatory cytokines, suggesting that exosome-associated TERRA augments innate immune signaling. These findings imply a previously unidentified extrinsic function for TERRA and a mechanism of communication between telomeres and innate immune signals in tissue and tumor microenvironments. PMID:26578789

  18. Telomeric repeat-containing RNA (TERRA) constitutes a nucleoprotein component of extracellular inflammatory exosomes.

    Science.gov (United States)

    Wang, Zhuo; Deng, Zhong; Dahmane, Nadia; Tsai, Kevin; Wang, Pu; Williams, Dewight R; Kossenkov, Andrew V; Showe, Louise C; Zhang, Rugang; Huang, Qihong; Conejo-Garcia, José R; Lieberman, Paul M

    2015-11-17

    Telomeric repeat-containing RNA (TERRA) has been identified as a telomere-associated regulator of chromosome end protection. Here, we report that TERRA can also be found in extracellular fractions that stimulate innate immune signaling. We identified extracellular forms of TERRA in mouse tumor and embryonic brain tissue, as well as in human tissue culture cell lines using RNA in situ hybridization. RNA-seq analyses revealed TERRA to be among the most highly represented transcripts in extracellular fractions derived from both normal and cancer patient blood plasma. Cell-free TERRA (cfTERRA) could be isolated from the exosome fractions derived from human lymphoblastoid cell line (LCL) culture media. cfTERRA is a shorter form (∼200 nt) of cellular TERRA and copurifies with CD63- and CD83-positive exosome vesicles that could be visualized by cyro-electron microscopy. These fractions were also enriched for histone proteins that physically associate with TERRA in extracellular ChIP assays. Incubation of cfTERRA-containing exosomes with peripheral blood mononuclear cells stimulated transcription of several inflammatory cytokine genes, including TNFα, IL6, and C-X-C chemokine 10 (CXCL10) Exosomes engineered with elevated TERRA or liposomes with synthetic TERRA further stimulated inflammatory cytokines, suggesting that exosome-associated TERRA augments innate immune signaling. These findings imply a previously unidentified extrinsic function for TERRA and a mechanism of communication between telomeres and innate immune signals in tissue and tumor microenvironments.

  19. Sulfates on Mars: Indicators of Aqueous Processes

    Science.gov (United States)

    Bishop, Janice L.; Lane, Melissa D.; Dyar, M. Darby; Brown, Adrian J.

    2006-01-01

    Recent analyses by MER instruments at Meridiani Planum and Gusev crater and the OMEGA instrument on Mars Express have provided detailed information about the presence of sulfates on Mars [1,2,3]. We are evaluating these recent data in an integrated multi-disciplinary study of visible-near-infrared, mid-IR and Mossbauer spectra of several sulfate minerals and sulfate-rich analog sites. Our analyses suggest that hydrated iron sulfates may account for features observed in Mossbauer and mid-IR spectra of Martian soils [4]. The sulfate minerals kieserite, gypsum and other hydrated sulfates have been identified in OMEGA spectra in the layered terrains in Valles Marineris and Terra Meridiani [2]. These recent discoveries emphasize the importance of studying sulfate minerals as tracers of aqueous processes. The sulfate-rich rock outcrops observed in Meridiani Planum may have formed in an acidic environment similar to acid rock drainage environments on Earth [5]. Because microorganisms typically are involved in the oxidation of sulfides to sulfates in terrestrial sites, sulfate-rich rock outcrops on Mars may be a good location to search for evidence of past life on that planet. Whether or not life evolved on Mars, following the trail of sulfate minerals will lead to a better understanding of aqueous processes and chemical weathering.

  20. Acidic Conditions During Open System Weathering on Late Noachian/Early Hesperian Mars? Newly Identified Outcrops of Alunite and Jarosite from Orbital CRISM Data

    Science.gov (United States)

    Ehlmann, Bethany; Dundar, Murat

    2016-10-01

    Sequences of Al-phyllosilicates atop Fe,Mg-phylloslicates occur in multiple regions of Mars, including Mawrth Vallis/northern Arabia Terra, Nili Fossae/Northeast Syrtis Major, Terra Sirenum/Eridania basin, northern Hellas, and portions of Valles Marineris. The sequences are exposed beneath unaltered capping materials with Early Hesperian surface ages, thus implying phyllosilicate formation occurred earlier. Because of the presence of clay minerals, the sequences are certainly a product of water interactions with rocks and sediments, but key questions remain about the environmental conditions implied. Are Al-phyllosilicates simply a result of alteration of a silicic precursor? Or do they represent the end product of substantial open system leaching of a basaltic protolith? Was open system leaching substantial because of high water throughput, long cumulative duration, acidity, or some combination? Each scenario leads to Al-phyllosilicate formation but with different accompanying mineral phases in response to pH, Eh, and chemical species concentrations in the fluids. Key to further progress in constraining the environmental conditions of alteration is more sophisticated spectral analyses to identify intermixed phases and isolate rare spectral classes within the Al phyllosilicate units.Here, we employ a newly developed, non-parametric Bayesian algorithm [1] for semi-automatic identification of rare spectral classes. We employ this algorithm on 139 CRISM images in areas with reported regional-scale occurrences of Al-phyllosilicates that were compiled from the literature [e.g. 2, 3]. Dozens of detections of the minerals alunite and jarosite were made with the algorithm and then verified by manual analysis. These sulfate hydroxides form only at low pHs, and thus their presence tightly constrains water chemistry. Crucial for understanding whether the alunite and jarosite deposits are contemporaneous with the Al phyllosilicates or later overprinting deposits is study of

  1. Regional Security Issues in Contemporary Saudi Arabia

    OpenAIRE

    Eriksen, Jonas Nogel; Kababo, Anas Yoseph; Madsen, Signe Røskva; Petersen, Asger Bagge

    2014-01-01

    In this project we seek to analyse what security issues the country of Saudi Arabia is facing in the Middle East and the Gulf. These issues are analysed from the theoretical framework of Barry Buzan, Ole Wæver and Jaap de Wilde, and their theory on Regional Security Complex. The analysis framework of securitization is divided into five sectors, our analysis being conducted only in the political, military, economic and societal sectors. This has allowed us to deconstruct and get an understandi...

  2. ERP Implementation Success Factors in Saudi Arabia

    OpenAIRE

    Malik F. Saleh; Muneer Abbad; Mohammed Al-Shehri

    2013-01-01

    A review of the literature on successful implementation of ERP reveals that there are many case studies undertaken by researches, but very few have empirically examined the success factors of ERP implementation. While most of those empirical studies were undertaken in Western countries, very few had examined the implementations in Middle Eastern countries and none in Saudi Arabia. Factors and challenges of ERP implementation in developing countries differ from those of Western countries. Henc...

  3. BOOK REVIEW: European Perceptions of Terra Australis

    Science.gov (United States)

    Sterken, Christiaan

    2012-12-01

    Terra Australis - the southern land - has been one of the most widespread concepts in European geography from the sixteenth to the eighteenth century. This book comprises a set of 14 interdisciplinary scholarly contributions that deal with personal perceptions of Terra Australis by cartographers and explorers, and with putting these perceptions in their historical and cultural environments. This book seems, at a first glance, to be very remote from astronomy - and even from the history of astronomy - however, as it also offers an excellent background to Captain James Cook's second voyage to observe the 1769 transit of Venus from Tahiti, it definitely is a work of truly interdisciplinary character. Cook's voyages, in fact, became a model in which key scientists of many nationalities and disciplines traveled together on ships. In these voyages, art, science, technology and political power were centralised and united. The chapters range across history, the visual arts, literature, popular culture, technology, politics and science. Issues of scientific reasoning are raised in the description of how people did think about the south before there even existed a perception of the unknown land - quite comparable to how ancient and early-modern astronomers had their thought about cosmology even before any observational data were available. Several early map systems - like the zonal and T-O maps (medieval world maps with the letter T inside an O representing the lands inside a circle of oceans) - are described, and the description of Roman geography shows the amazing fact that theory and practice were not unified, and existed independently of each other insofar that a real paradox between theory and observation had persisted for a very long time. The maps and charts also exemplify the long-lasting consequences of early modern copy-paste practice: navigators copied original sketch charts of coasts that were previously unknown to them, herewith committing many translation and

  4. Mars habitat

    Science.gov (United States)

    Ayers, Dale; Barnes, Timothy; Bryant, Woody; Chowdhury, Parveen; Dillard, Joe; Gardner, Vernadette; Gregory, George; Harmon, Cheryl; Harrell, Brock; Hilton, Sherrill

    1991-01-01

    The objective of this study is to develop a conceptual design for a permanently manned, self-sustaining Martian facility, to accommodate a crew of 20 people. The goal is to incorporate the major functions required for long term habitation in the isolation of a barren planet into a thriving ecosystem. These functions include living, working, service, and medical facilities as well as a green house. The main design task was to focus on the internal layout while investigating the appropriate structure, materials, and construction techniques. The general concept was to create a comfortable, safe living environment for the crew members for a stay of six to twelve months on Mars. Two different concepts were investigated, a modular assembly reusable structure (MARS) designated Lavapolis, and a prefabricated space frame structure called Hexamars. Both models take into account factors such as future expansion, radiation shielding, and ease of assembly.

  5. Mars attacks.

    Science.gov (United States)

    Cohain, Judy Slome

    2008-01-01

    "Mars Attacks" is a new term coined to describe unjustified violation of women by care providers at the time of birth, as well as the purposeful abandonment of the peer review system by major obstetric journals and the abandonment of the use of research evidence by ACOG in their latest protocols, in order to justify continued use of this form of violence against women. PMID:19244777

  6. Effect of MODIS Terra radiometric calibration improvements on Collection 6 Deep Blue aerosol products: Validation and Terra/Aqua consistency

    Science.gov (United States)

    Sayer, A. M.; Hsu, N. C.; Bettenhausen, C.; Jeong, M.-J.; Meister, G.

    2015-12-01

    The Deep Blue (DB) algorithm's primary data product is midvisible aerosol optical depth (AOD). DB applied to Moderate Resolution Imaging Spectroradiometer (MODIS) measurements provides a data record since early 2000 for MODIS Terra and mid-2002 for MODIS Aqua. In the previous data version (Collection 5, C5), DB production from Terra was halted in 2007 due to sensor degradation; the new Collection 6 (C6) has both improved science algorithms and sensor radiometric calibration. This includes additional calibration corrections developed by the Ocean Biology Processing Group to address MODIS Terra's gain, polarization sensitivity, and detector response versus scan angle, meaning DB can now be applied to the whole Terra record. Through validation with Aerosol Robotic Network (AERONET) data, it is shown that the C6 DB Terra AOD quality is stable throughout the mission to date. Compared to the C5 calibration, in recent years the RMS error compared to AERONET is smaller by ˜0.04 over bright (e.g., desert) and ˜0.01-0.02 over darker (e.g., vegetated) land surfaces, and the fraction of points in agreement with AERONET within expected retrieval uncertainty higher by ˜10% and ˜5%, respectively. Comparisons to the Aqua C6 time series reveal a high level of correspondence between the two MODIS DB data records, with a small positive (Terra-Aqua) average AOD offset radiometric calibration efforts and that the C6 MODIS Terra DB AOD data remain stable (to better than 0.01 AOD) throughout the mission to date, suitable for quantitative scientific analyses.

  7. Monitoring on Xi'an Ground Fissures Deformation with TerraSAR-X Data%采用TerraSAR-X数据监测西安地裂缝形变

    Institute of Scientific and Technical Information of China (English)

    赵超英; 张勤; 朱武; Lu Zhong

    2012-01-01

    Owing to the fine resolution of TerraSAR-X data provided since 2007,this paper applied 6 TerraSAR data(strip mode) during 3rd Dec.2009 to 23rd Mar.2010 to detect and monitor the active fissures over Xi'an region.Three themes have been designed for high precision detection and monitoring of Xi'an-Chang'an fissures,as small baseline subsets(SBAS) to test the atmospheric effects of differential interferograms pair stepwise,2-pass differential interferogram with very short baseline perpendicular to generate the whole deformation map with 44 days interval,and finally,corner reflector(CR) technique was used to closely monitor the relative deformation time series between two CRs settled crossing two ground fissures.Results showed that TerraSAR data are a good choice for small-scale ground fissures detection and monitoring,while special considerations should be taken for their great temporal and baseline decorrelation.Secondly,ground fissures in Xi'an were mostly detected at the joint section of stable and deformable regions.Lastly,CR-InSAR had potential ability to monitor relative deformation crossing fissures with millimeter precision.%基于3m分辨率的TerraSAR-X数据对覆盖西安地区的活动地裂缝进行了定位与监测研究。数据为2009-12-03~2010-03-23共6景Strip模式数据。实验结果显示,高分辨率TerraSAR数据是监测地裂缝很好的数据源,但为了获取高精度的监测成果还需要特别考虑时间和基线去相干因素。二轨法监测结果显示,活动地裂缝往往出现在稳定区域与形变区域的转折部位,而采用人工角反射器技术可以监测出mm量级的地裂缝相对形变信息。

  8. The dangers of incense burning: COPD in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Al-Kassimi FA

    2013-05-01

    Full Text Available Feisal A Al-KassimiDepartment of Medicine, College of Medicine, King Saud University, Riyadh, Saudi ArabiaWe read with great interest the article titled "Chronic obstructive pulmonary disease: hospital and intensive care unit outcomes in the Kingdom of Saudi Arabia"1 and we would like to comment on its methodology.View original paper by Alaithan and colleagues.

  9. Women and Education in Saudi Arabia: Challenges and Achievements

    Science.gov (United States)

    Hamdan, Amani

    2005-01-01

    The historical socio-economic and political conditions of Saudi Arabia are an essential aspect of understanding a woman's position in Saudi society. The persistence of women's exclusion from public life in contemporary Saudi Arabia is one of the most heated debates not only among Muslims but also worldwide, as Saudi society comes under more and…

  10. Mars Albedo

    Science.gov (United States)

    2001-01-01

    These two views of Mars are derived from the MGS Thermal Emission Spectrometer (TES) measurements of global broadband (0.3 - 3.0 microns) visible and near-infrared reflectance, also known as albedo. The range of colors are in dimensionless units. The values are the ratio of the amount of electromagnetic energy reflected by the surface to the amount of energy incident upon it from the sun (larger values are brighter surfaces).The TES instrument was built by Santa Barbara Remote Sensing and is operated by Philip R. Christensen, of Arizona State University, Tempe, AZ.

  11. Terra firma-forme dermatosis: Case Series and dermoscopic features.

    Science.gov (United States)

    Abdel-Razek, Moheb M; Fathy, Hanan

    2015-10-01

    Terra firma-forme dermatosis (TFFD) is characterized by dirt-like skin lesions that disappear after rubbing with alcohol. We describe the dermoscopic features of TFFD before and after alcohol swabbing in six patients. All patients showed similar dermoscopic appearance with large polygonal plate-like brown scales arranged together giving a mosaic pattern. These features disappear completely after isopropyl alcohol swabbing of the lesions. In conclusion dermoscopy can assist in the evaluation of terra firma-forme dermatosis and the dermoscopic evaluation of other dirty dermatoses is recommended in the future to compare findings with TFFD.

  12. Cócs. Hallmark of the Terra Alta

    OpenAIRE

    Maria Del Loreto Meix

    2004-01-01

    This article looks at the traditional cake making in the Terra Alta (Catalonien) area linked to festivities, and in particular the pastries usually made. In this area the pastries are known as cócs, a word common to Terra Alta and the neighbouring districts of Ribera d'Ebre and the Priorat. Locally produced mistelle, sweet or rancid wine is served with the pastries. Nowadays, the bakeries and cake makers in the area's towns and villages also produce traditionally crafted products, tha...

  13. Terra preta de índio (TPI) Anthropogenic Dark Earth.

    OpenAIRE

    Devide, Antonio Carlos Pries

    2012-01-01

    As pesquisas arqueológicas sobre a Terra Preta de Índio no Brasil vem despertando a atenção mundial devido às propriedades que o solo adquiriu através da adição de grande quantidade de carbono e restos orgânicos e cerâmicos. Essa Revisão de Literatura possibilita uma introdução sobre Terra Preta de Índio e as pesquisas sobre o Biochar (Biocarvão).

  14. Sol-Terra - AN Operational Space Weather Forecasting Model Framework

    Science.gov (United States)

    Bisi, M. M.; Lawrence, G.; Pidgeon, A.; Reid, S.; Hapgood, M. A.; Bogdanova, Y.; Byrne, J.; Marsh, M. S.; Jackson, D.; Gibbs, M.

    2015-12-01

    The SOL-TERRA project is a collaboration between RHEA Tech, the Met Office, and RAL Space funded by the UK Space Agency. The goal of the SOL-TERRA project is to produce a Roadmap for a future coupled Sun-to-Earth operational space weather forecasting system covering domains from the Sun down to the magnetosphere-ionosphere-thermosphere and neutral atmosphere. The first stage of SOL-TERRA is underway and involves reviewing current models that could potentially contribute to such a system. Within a given domain, the various space weather models will be assessed how they could contribute to such a coupled system. This will be done both by reviewing peer reviewed papers, and via direct input from the model developers to provide further insight. Once the models have been reviewed then the optimal set of models for use in support of forecast-based SWE modelling will be selected, and a Roadmap for the implementation of an operational forecast-based SWE modelling framework will be prepared. The Roadmap will address the current modelling capability, knowledge gaps and further work required, and also the implementation and maintenance of the overall architecture and environment that the models will operate within. The SOL-TERRA project will engage with external stakeholders in order to ensure independently that the project remains on track to meet its original objectives. A group of key external stakeholders have been invited to provide their domain-specific expertise in reviewing the SOL-TERRA project at critical stages of Roadmap preparation; namely at the Mid-Term Review, and prior to submission of the Final Report. This stakeholder input will ensure that the SOL-TERRA Roadmap will be enhanced directly through the input of modellers and end-users. The overall goal of the SOL-TERRA project is to develop a Roadmap for an operational forecast-based SWE modelling framework with can be implemented within a larger subsequent activity. The SOL-TERRA project is supported within

  15. Wind power potential of Saudi Arabia

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Ph.

    1985-01-01

    Wind data for 20 locations in Saudi Arabia have been analysed. Monthly and annual mean wind speeds and wind powers have been determined. The latter range from 2.5 to 4.4 m s/sup -1/, and from 21.8 to 77.7 W m/sup -2/, respectively. Specific outputs from two hypothetical aerogenerators with rated wind speeds of 5 and 7 m s/sup -1/ have been estimated. Examples of monthly mean wind speed and wind power temporal variations are given. Results suggest that wind power would be more profitably used for local small-scale applications. (author).

  16. Geologic Map of MTM 35337, 40337, and 45337 Quadrangles, Deuteronilus Mensae Region of Mars

    Science.gov (United States)

    Chuang, Frank C.; Crown, David A.

    2009-01-01

    Deuteronilus Mensae, first defined as an albedo feature at lat 35.0 deg N., long 5.0 deg E., by U.S. Geological Survey (USGS) and International Astronomical Union (IAU) nomenclature, is a gradational zone along the dichotomy boundary in the northern mid-latitudes of Mars. The boundary in this location includes the transition from the rugged cratered highlands of Arabia Terra to the northern lowland plains of Acidalia Planitia. Within Deuteronilus Mensae, polygonal mesas are prominent along with features diagnostic of Martian fretted terrain, including lobate debris aprons, lineated valley fill, and concentric crater fill. Lobate debris aprons, as well as the valley and crater fill deposits, are geomorphic indicators of ground ice, and their concentration in Deuteronilus Mensae is of great interest because of their potential association with Martian climate change. The paucity of impact craters on the surfaces of debris aprons and the presence of ice-cemented mantle material imply young (for example, Amazonian) surface ages that are consistent with recent climate change in this region of Mars. North of Deuteronilus Mensae are the northern lowlands, a potential depositional sink that may have had large standing bodies of water or an ocean in the past. The northern lowlands have elevations that are several kilometers below the ancient cratered highlands with significantly younger surface ages. The morphologic and topographic characteristics of the Deuteronilus Mensae region record a diverse geologic history, including significant modification of the ancient highland plateau and resurfacing of low-lying regions. Previous studies of this region have interpreted a complex array of geologic processes, including eolian, fluvial and glacial activity, coastal erosion, marine deposition, mass wasting, tectonic faulting, effusive volcanism, and hydrovolcanism. The origin and age of the Martian crustal dichotomy boundary are fundamental questions that remain unresolved at the

  17. Quantitative interaction screen of telomeric repeat-containing RNA reveals novel TERRA regulators.

    Science.gov (United States)

    Scheibe, Marion; Arnoult, Nausica; Kappei, Dennis; Buchholz, Frank; Decottignies, Anabelle; Butter, Falk; Mann, Matthias

    2013-12-01

    Telomeres are actively transcribed into telomeric repeat-containing RNA (TERRA), which has been implicated in the regulation of telomere length and heterochromatin formation. Here, we applied quantitative mass spectrometry (MS)-based proteomics to obtain a high-confidence interactome of TERRA. Using SILAC-labeled nuclear cell lysates in an RNA pull-down experiment and two different salt conditions, we distinguished 115 proteins binding specifically to TERRA out of a large set of background binders. While TERRA binders identified in two previous studies showed little overlap, using quantitative mass spectrometry we obtained many candidates reported in these two studies. To test whether novel candidates found here are involved in TERRA regulation, we performed an esiRNA-based interference analysis for 15 of them. Knockdown of 10 genes encoding candidate proteins significantly affected total cellular levels of TERRA, and RNAi of five candidates perturbed TERRA recruitment to telomeres. Notably, depletion of SRRT/ARS2, involved in miRNA processing, up-regulated both total and telomere-bound TERRA. Conversely, knockdown of MORF4L2, a component of the NuA4 histone acetyltransferase complex, reduced TERRA levels both globally and for telomere-bound TERRA. We thus identified new proteins involved in the homeostasis and telomeric abundance of TERRA, extending our knowledge of TERRA regulation.

  18. Genome Sequences of Gordonia terrae Bacteriophages Phinally and Vivi2.

    Science.gov (United States)

    Pope, Welkin H; Anderson, Kaitlyn C; Arora, Charu; Bortz, Michael E; Burnet, George; Conover, David H; D'Incau, Gina M; Ghobrial, Jonathan A; Jonas, Audrey L; Migdal, Emily J; Rote, Nicole L; German, Brian A; McDonnell, Jill E; Mezghani, Nadia; Schafer, Claire E; Thompson, Paige K; Ulbrich, Megan C; Yu, Victor J; Furbee, Emily C; Grubb, Sarah R; Warner, Marcie H; Montgomery, Matthew T; Garlena, Rebecca A; Russell, Daniel A; Jacobs-Sera, Deborah; Hatfull, Graham F

    2016-08-18

    Bacteriophages Phinally and Vivi2 were isolated from soil from Pittsburgh, Pennsylvania, USA, using host Gordonia terrae 3612. The Phinally and Vivi2 genomes are 59,265 bp and 59,337 bp, respectively, and share sequence similarity with each other and with GTE6. Fewer than 25% of the 87 to 89 putative genes have predictable functions.

  19. S'accabadora: viaggio nella terra del vento.

    Directory of Open Access Journals (Sweden)

    Roberta Murroni

    2010-11-01

    Full Text Available S'accabadora: viaggio nella terra del vento. Con testi dell'autrice.(Giovanna Mulas, Accabadora (Nessuno doveva sapere, nessuno doveva sentire Como - Il Ciliegio, in coll. Con Acco Editore, 2010, con illustrazioni a colori e b/n di Pinna Podestà, 112 pp.di Roberta Murroni

  20. Mechanical unfolding of long human telomeric RNA (TERRA)

    OpenAIRE

    Garavís, M.; Bocanegra, Rebeca; Herrero-Galán, E.; González, Carlos; Villasante, Alfredo; Arias-González, J. R.

    2013-01-01

    We report the first single molecule investigation of TERRA molecules. By using optical-tweezers and other biophysical techniques, we have found that long RNA constructions of up to 25 GGGUUA repeats form higher order structures comprised of single parallel G-quadruplex blocks, which unfold at lower forces than their DNA counterparts. © 2013 The Royal Society of Chemistry.

  1. SITE TECHNOLOGY CAPSULE: TERRA-KLEEN SOLVENT EXTRACTION TECHNOLOGY

    Science.gov (United States)

    Remediation of PCBs in soils has been difficult to implement on a full-scale, cost-effective basis. The Terra-Kleen solvent extraction system has overcome many of the soil handling, contaminant removal, and regulatory restrictions that have made it difficult to implement a cost-e...

  2. Terra Vac In Situ Vacuum Extraction System: Applications Analysis Report

    Science.gov (United States)

    This document is an evaluation of the Terra Vac in situ vacuum extraction system and its applicability as a treatment method for waste site cleanup. This report analyzes the results from the Superfund Innovative Technology Evaluation (SITE) Program’s 56-day demonstration at t...

  3. Telomeric Repeat Containing RNA (TERRA): Aging and Cancer.

    Science.gov (United States)

    Sinha, Sonam; Shukla, Samriddhi; Khan, Sajid; Farhan, Mohammad; Kamal, Mohammad Amjad; Meeran, Syed Musthapa

    2015-01-01

    Telomeric repeat containing RNAs (TERRA) are small RNA molecules synthesized from telomeric regions which were previously considered as silent genomic domains. In normal cells, these RNAs are transcribed in a direction from subtelomeric region towards the chromosome ends, but in case of cancer cells, their expression remains limited or absent. Telomerase is a rate limiting enzyme for cellular senescence, cancer and aging. Most of the studies deal with the manipulation of telomerase enzyme in cancer and aging either by synthetic oligonucleotide or by natural phytochemicals. Here, we collected evidences and discussed intensely about the bio-molecular structure of TERRA, naturally occurring ligands of telomerase, and their genetic and epigenetic regulations in aging associated diseases. Due to their capability to act as naturally occurring ligands of telomerase, these RNAs can overcome the limitations possessed by synthetic oligonucleotides, which are aimed against telomerase. Drugs specifically targeting TERRA molecules could modulate telomerase-mediated telomere lengthening. Thus, targeting TERRA-mediated regulation of telomerase would be a promising therapeutic strategy against cancer and age-associated diseases.

  4. Genome Sequences of Gordonia terrae Phages Benczkowski14 and Katyusha.

    Science.gov (United States)

    Pope, Welkin H; Benczkowski, Matthew S; Green, Daryn E; Hwang, Melina; Kennedy, Bryan; Kocak, Bradley; Kruczek, Ellen; Lin, Leon; Moretti, Matthew L; Onelangsy, Faith L; Mezghani, Nadia; Milliken, Katherine A; Toner, Chelsea L; Thompson, Paige K; Ulbrich, Megan C; Furbee, Emily C; Grubb, Sarah R; Warner, Marcie H; Montgomery, Matthew T; Garlena, Rebecca A; Russell, Daniel A; Jacobs-Sera, Deborah; Hatfull, Graham F

    2016-01-01

    Bacteriophages Katyusha and Benczkowski14 are newly isolated phages that infect Gordonia terrae 3612. Both have siphoviral morphologies with isometric heads and long tails (500 nm). The genomes are 75,380 bp long and closely related, and the tape measure genes (9 kbp) are among the largest to be identified. PMID:27340062

  5. Bilateral topographic symmetry patterns across Aphrodite Terra, Venus

    International Nuclear Information System (INIS)

    Western Aphrodite Terra, Venus, is characterized by a series of parallel linear structural discontinuities 2000--4000 km in length and 100--200 km wide, which strike at high angles to the general topographic trend of the Aphrodite Terra highlands. The broad chracteristics of the cross-strike discontinuities (CSDs) are similar to both strike-slip fault zones and terrestrial oceanic fracture zones. In an effort to distinguish between these two hypotheses, topographic profiles were taken across Aphrodite Terra to test for bilateral symmetry of the type associated with thermal boundary layer topography at divergent plate boundaries on Earth. In addition to a broad bilateral symmetry at a range of angles across Aphrodite Terra, detailed bilateral symmetry is observed within domains between linear discontinuities in directions generally parallel to the strike of the discontinuities. In addition, within a domain the centers of symmetry of several profiles define a linear rise crest that is oriented normal to the bounding CSDs and terminates against them

  6. Mars Public Engagement Overview

    Science.gov (United States)

    Johnson, Christine

    2009-01-01

    This viewgraph presentation reviews the Mars public engagement goal to understand and protect our home planet, explore the Universe and search for life, and to inspire the next generation of explorers. Teacher workshops, robotics education, Mars student imaging and analysis programs, MARS Student Imaging Project (MSIP), Russian student participation, MARS museum visualization alliance, and commercialization concepts are all addressed in this project.

  7. 10 years of Terra Outreach over the Internet

    Science.gov (United States)

    Yuen, K.; Riebeek, H.; Chambers, L. H.

    2009-12-01

    1 Author Yuen, Karen JPL (818) 393-7716 2 Author Riebeek, Holli Sigma Space Corporation (department) at NASA Goddard Space Flight Center (Institution), Greenbelt, Maryland 3 Author Chambers, Lin NASA Abstract: Since launch, Terra has returned about 195 gigabytes (level 0) of data per day or 1 terabyte every 5 days. Few outlets were able to accommodate and quickly share that amount of information as well as the Internet. To honor the 10-year anniversary of the launch of Terra, we would like to highlight the education and outreach efforts of the Terra mission on the Internet and its reach to the science attentive public. The Internet or web has been the primary way of delivering Terra content to different groups- from formal and informal education to general public outreach. Through the years, many different web-based projects have been developed, and they were of service to a growing population of the science attentive public. One of Terra’s original EPO activities was the Earth Observatory. It was initially dedicated to telling the remote sensing story of Terra, but quickly grew to include science and imagery from other sensors. The web site allowed for collaboration across NASA centers, universities and other organizations by exchanging and sharing of story ideas, news and images. The award winning Earth Observatory helped pave the way for the more recently funded development of the Climate Change website. With its specific focus on climate change studies, once again, Terra stories and images are shared with an even more specific audience base. During the last 10 years, Terra as a mission has captured the imagination of the public through its visually stunning and artistically arresting images. With its five instruments of complementary but unique capabilities, the mission gave the world not just pretty pictures, but scientific data-based images. The world was able to see from space everything from calving icebergs to volcanic eruption plumes and the eye of a

  8. Mars Scouts: An Overview

    OpenAIRE

    Matousek, Steve

    2001-01-01

    The Mars Program institutes the Mars Scout Missions in order to address science goals in the program not otherwise covered in the baseline Mars plan. Mars Scout missions will be Principal-Investigator (PI) led science missions. Analogous to the Discovery Program, PI led investigations optimize the use of limited resources to accomplish the best focused science and allow the flexibility to quickly respond to discoveries at Mars. Scout missions also require unique investments in technology and ...

  9. Telomeric noncoding RNA TERRA is induced by telomere shortening to nucleate telomerase molecules at short telomeres.

    Science.gov (United States)

    Cusanelli, Emilio; Romero, Carmina Angelica Perez; Chartrand, Pascal

    2013-09-26

    Elongation of a short telomere depends on the action of multiple telomerase molecules, which are visible as telomerase RNA foci or clusters associated with telomeres in yeast and mammalian cells. How several telomerase molecules act on a single short telomere is unknown. Herein, we report that the telomeric noncoding RNA TERRA is involved in the nucleation of telomerase molecules into clusters prior to their recruitment at a short telomere. We find that telomere shortening induces TERRA expression, leading to the accumulation of TERRA molecules into a nuclear focus. Simultaneous time-lapse imaging of telomerase RNA and TERRA reveals spontaneous events of telomerase nucleation on TERRA foci in early S phase, generating TERRA-telomerase clusters. This cluster is subsequently recruited to the short telomere from which TERRA transcripts originate during S phase. We propose that telomere shortening induces noncoding RNA expression to coordinate the recruitment and activity of telomerase molecules at short telomeres.

  10. “SEM TEKOA NÃO HÁ TEKO – SEM TERRA NÃO HÁ CULTURA”: ESTUDO E DESENVOLVIMENTO AUTO-SUSTENTÁVEL

    Directory of Open Access Journals (Sweden)

    ALDO LITAIFF

    2008-12-01

    Full Text Available ABSTRACT: This article reports the results of the “Sem tekoa não há teko, sem terra não há cultura: estudo e desenvolvimento auto-sustentável de comunidades indígenas guarani” project. It was carried out by UNISUL (University of the South of Santa Catarina and byUFSC (Federal University of Santa Catarina from March, 2002 through December, 2007, and aimed at promoting economic modes appropriate for the ethnodevelopment and auto sustainability of the guarani land at the coast of the state of Santa Catarina, a measure compatible with teko, that is, the way of beeing, the guarani culture.RESUMO: A finalidade deste artigo é relatar os resultados do projeto “Sem tekoa não há teko, sem terra não há cultura: estudo e desenvolvimento auto-sustentável de comunidades indígenas guarani”. Executado conjuntamente pela UFSC (Universidade Federal de SantaCatarina e Unisul (Universidade do Sul de Santa Catarina, entre março de 2002 e dezembro de 2007, o projeto visava como objetivo geral, incentivar formas econômicas apropriadas aoetnodesenvolvimento e à auto-sustentabilidade de terras indígenas guarani localizadas no litoral do Estado de Santa Catarina, medida compatível com “teko”, ou seja, modo de ser ou cultura guarani.

  11. Climate change and animals in Saudi Arabia.

    Science.gov (United States)

    Williams, Joseph B; Shobrak, Mohammed; Wilms, Thomas M; Arif, Ibrahim A; Khan, Haseeb A

    2012-04-01

    Global warming is occurring at an alarming rate and predictions are that air temperature (T a) will continue to increase during this century. Increases in T a as a result of unabated production of greenhouse gases in our atmosphere pose a threat to the distribution and abundance of wildlife populations worldwide. Although all the animals worldwide will likely be affected by global warming, diurnal animals in the deserts will be particularly threatened in the future because T as are already high, and animals have limited access to water. It is expected that Saudi Arabia will experience a 3-5 °C in T a over the next century. For predicting the consequences of global warming for animals, it is important to understand how individual species will respond to higher air temperatures. We think that populations will not have sufficient time to make evolutionary adjustments to higher T a, and therefore they will be forced to alter their distribution patterns, or make phenotypic adjustments in their ability to cope with high T a. This report examines how increases in T a might affect body temperature (T b) in the animals of arid regions. We chose three taxonomic groups, mammals, birds, and reptiles (Arabian oryx, Arabian spiny-tailed lizard, vultures, and hoopoe larks) from Saudi Arabia, an area in which T a often reaches 45 °C during midday in summer. When T a exceeds T b, animals must resort to behavioral and physiological methods to control their T b; failure to do so results in death. The observations of this study show that in many cases T b is already close to the upper lethal limit of around 47° C in these species and therefore allowing their T b to increase as T a increases are not an option. We conclude that global warming will have a detrimental impact on a wide range of desert animals, but in reality we know little about the ability of most animals to cope with change in T a. The data presented should serve as base-line information on T b of animals in the

  12. Can we expect habitable niches for cyanobacteria on Mars?

    Science.gov (United States)

    de Vera, Jean-Pierre Paul; Lorek, Andreas; Koncz, Alexander; Billi, Daniela; Baqué, Mickael; Leya, Thomas; Brown, Sarah; Cockell, Charles

    2013-04-01

    The most resistant cyanobacteria can be found in tropic deserts and in polar and alpine habitats. The reason for their resistance can be explained by their occurrence in intensely irradiated, very dry and/or cold environments which are supposed to be as close as possible similar to Martian surface conditions. A systematically approach comparing measurements on photosynthetic activity of cyanobacteria in relation to measured environmental parameters obtained in Mars analog field sites with data collected from space exposed samples or during Mars simulation experiments will show differences and common results after analyzing the investigated organisms. Some of the investigated species are foreseen to be exposed during the next ESA-space-exposure experiment BIOMEX either directly to real space conditions on space exposure platforms like EXPOSE-R2 on the International Space Station or to Mars simulation conditions in a Mars simulation chamber. Some of the species were still exposed to both of the extreme environmental conditions and some of the results will be presented and might serve for future investigations as references. We will emphasize that in parallel monitoring of environmental parameters on Mars analog field sites was performed as well as partly in space and in the simulation chambers. This experimental combination might help to get a better impression about the influence of each of the tested parameters on metabolic activity of the tested cyanobacteria in complete different planetary environments comparing characterized habitats on our home planet Earth with those we might expect according to recently observed data on Mars. The outcome of this work could be relevant to classify e.g. Mars as a habitable planet by a new combination of different experimental and biological approaches and to evaluate and discuss the likelihood of terra forming Mars in the far future.

  13. Distribution And Mineralogy Of The Clay Deposits In Saudi Arabia

    OpenAIRE

    Al Mohandis, Ahmed A. [احمد عبد القادر المهندس

    1993-01-01

    The main goal of this paper is to characterize the mineral clay deposits in Saudi Arabia; especially their mineral composition, deposit size, geological setting and possible uses. Different published reports and papers on clay deposits of Saudi Arabia have been reviewed. Three major clay deposits have been studied by XRD, DTA and chemical analyses. Saudi clay deposits consist generally of kaolinite as a major mineral, and small amounts other clay minerals, such as montmorillonite and illite. ...

  14. Role of social media in brand development in Saudi Arabia

    OpenAIRE

    Abeer Abdullah Al Saud; Muhammad Rahatullah Khan (Rahatullah, M, K.,)

    2013-01-01

    Literature is ripe with the scholarly contributions on brand development from all aspects. The new marketing tools and techniques are introduced frequently. However, the impact social media has had on brand development is no match to traditional promotion in 4Ps. The information about Saudi Arabia is specially rare. This article based on a survey of 200 social media users on www.surveymonkey.com evaluates the role of social media in brand development in Saudi Arabia. The results from this Sau...

  15. Counter-Terrorism in Saudi Arabia: Narratives, Practices and Challenges

    OpenAIRE

    AlMaawi, Mohammad

    2016-01-01

    Since 9/11, both in the Middle East and worldwide, the academic, political and religious focus on extreme radicalisation has intensified. The attacks carried out in Riyadh, the capital of the Kingdom of Saudi Arabia, by Al-Qaeda in 2003, motivated a succession of bombings within and outside of the Kingdom. These events have led to a plethora of general and specific studies to understand the phenomenon of extremism. This thesis investigates radicalisation in Saudi Arabia since 2001, focus...

  16. Smartphone addiction among university students in Riyadh, Saudi Arabia

    OpenAIRE

    Alosaimi, Fahad D; Alyahya, Haifa; Alshahwan, Hatem; Mahyijari, Nawal Al; Shaffi A Shaik

    2016-01-01

    Objectives: To investigate the prevalence and correlates of smartphone addiction among university students in Saudi Arabia. Methods: This cross-sectional study was conducted in King Saud University, Riyadh, Kingdom of Saudi Arabia between September 2014 and March 2015. An electronic self administered questionnaire and the problematic use of mobile phones (PUMP) Scale were used. Results: Out of 2367 study subjects, 27.2% stated that they spent more than 8 hours per day using their smartphones....

  17. Awareness of cardiovascular disease in eastern Saudi Arabia

    OpenAIRE

    Al-Baghli, Nadira A.; Al-Ghamdi, Aqeel J.; Khalid A Al-Turki; Ahmad G El-Zubaier; Al-Mostafa, Bader A.; Fadel A Al-Baghli; Al-Ameer, Mahmood M.

    2010-01-01

    Objective: To estimate the awareness of cardiovascular disease (CVD) and their determinants in a screening campaign in the eastern province of Saudi Arabia. Materials and Methods: All national residents in the eastern province of Saudi Arabia aged 30 years and above, were invited to participate in a screening campaign for the early detection of diabetes and hypertension at more than 300 examination posts throughout the eastern province. A pre-structured questionnaire was designed to collect d...

  18. An overview of nursing in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Mansour Saleh AlYami

    2014-01-01

    Full Text Available Achieving and maintaining a stable nursing workforce is an important issue for the well-being of the rapidly growing population of Saudi Arabia. However, high turnover of expatriate staff and low recruitment of Saudi nationals have led to a serious staff shortage in the professions, particularly of well-qualified and experienced nurses. Nursing leaders need to work to improve the image of nurses and facilitate the recruitment of women into the nursing profession. Reduced working hours and part-time contracts with increased salaries and benefits could attract more young women to the profession, as might the provision of facilities such as private transportation and on-site childcare. Furthermore, establishing a national association for nurses would advance the nursing profession and help to ensure that all nurses undertake fully comprehensive training before entering the workforce.

  19. Indonesians in Saudi Arabia: Worhsip and Work

    Directory of Open Access Journals (Sweden)

    Laurence Husson

    2014-03-01

    Full Text Available This article, which  opens a new  line of research,  is intended  to make a first assessment of the consequences  of Indonesian migration to saudi Arabia,  in particular  during  the  first half of the 2Oth century-a period when the immigration is bound  up with the pilgrimage from which Saudi Arabia draws a large part of its revenues. It must be added  that while documentary  evidence and partial studies on  this period  exist,  it turns out that documentation on the contemporary period  is scarce. This article also  is concerned with describing the evolution  of certain striking  aspects of the close  relation  between  the pilgrimage to Mecca  and Indonesian migrants  looking  for work.  We need to consider  the methods  of hiring  labor,  the networks  involved  in recruiting it, the organization  of travel,  as well as the increasing indebtedness  of the migrants  through  intermediaries  who, more and more professionally, arrange  these attempts  to live abroad, prompted in many cases by the same desire  for wealth.Copyright (c 2014 by SDI. All right reserved.DOI: 10.15408/sdi.v4i4.767

  20. Glomerulonephritis in Saudi Arabia: A Review

    Directory of Open Access Journals (Sweden)

    Mitwalli Ahmed

    2000-01-01

    Full Text Available Glomerulonephritis (GN is one of the leading causes of end-stage renal disease. A good understanding of its pattern and prevalence as well as exploration of effective therapeutic strategies for protecting the glomerulus, would have tremendous impact on public health. In the Kingdom of Saudi Arabia (KSA, focal and segmental glomerulo sclerosis (FSGS is the commonest type of primary glomerular diseases (PGD encountered in clinical practice. Its prevalence varies from less than 4% in Gizan, in the southern part of KSA, to approximately 35% in Riyadh, central Saudi Arabia. In our experience, the nephrotic syndrome was the commonest mode of presentation of FSGS. Response to corticosteroid therapy is generally poor and the mortality rate is high. Mesangioproliferative GN is the second most common GN constituting up to 25% of PGD in our experience. Other researchers from different parts of the Kingdom, however, have given prevalence rates ranging from 8 to 57.1%. The reported prevalence of Immunoglobulin-A nephropathy (IgAN in KSA ranges from 5.8% to 13.6%. It is more common in the elderly, and men are affected more often than women. In contrast to KSA, IgAN is the commonest PGD in Japan, China, Hong Kong, Singapore and Taiwan. Membranous GN (MGN is less common in KSA than encountered elsewhere, the prevalence ranging from 3.9 to 21.8%. Nephropathy secondary to systemic diseases are also common in KSA. Lupus nephritis (LN accounted for 48.5% of secondary glomerular diseases (SGD with the combination of WHO classes III and IV (aggressive types of LN accounting for 56% of all patients. LN is another disease where differences in racial susceptibility may account for the uneven distribution. Post-streptococcal GN seems to be declining in frequency in KSA, the reported prevalence ranging from 2.7% to 2.9%.

  1. Summary of Terra and Aqua MODIS Long-Term Performance

    Science.gov (United States)

    Xiong, Xiaoxiong (Jack); Wenny, Brian N.; Angal, Amit; Barnes, William; Salomonson, Vincent

    2011-01-01

    Since launch in December 1999, the MODIS ProtoFlight Model (PFM) onboard the Terra spacecraft has successfully operated for more than 11 years. Its Flight Model (FM) onboard the Aqua spacecraft, launched in May 2002, has also successfully operated for over 9 years. MODIS observations are made in 36 spectral bands at three nadir spatial resolutions and are calibrated and characterized regularly by a set of on-board calibrators (OBC). Nearly 40 science products, supporting a variety of land, ocean, and atmospheric applications, are continuously derived from the calibrated reflectances and radiances of each MODIS instrument and widely distributed to the world-wide user community. Following an overview of MODIS instrument operation and calibration activities, this paper provides a summary of both Terra and Aqua MODIS long-term performance. Special considerations that are critical to maintaining MODIS data quality and beneficial for future missions are also discussed.

  2. Geological Mapping of the Lada Terra (V-56) Quadrangle, Venus

    Science.gov (United States)

    Kumar, P. Senthil; Head, James W., III

    2009-01-01

    Geological mapping of the V-56 quadrangle (Fig. 1) reveals various tectonic and volcanic features and processes in Lada Terra that consist of tesserae, regional extensional belts, coronae, volcanic plains and impact craters. This study aims to map the spatial distribution of different material units, deformational features or lineament patterns and impact crater materials. In addition, we also establish the relative age relationships (e.g., overlapping or cross-cutting relationship) between them, in order to reconstruct the geologic history. Basically, this quadrangle addresses how coronae evolved in association with regional extensional belts, in addition to evolution of tesserae, regional plains and impact craters, which are also significant geological units of Lada Terra.

  3. Cócs. Hallmark of the Terra Alta

    Directory of Open Access Journals (Sweden)

    Maria Del Loreto Meix

    2004-04-01

    Full Text Available This article looks at the traditional cake making in the Terra Alta (Catalonien area linked to festivities, and in particular the pastries usually made. In this area the pastries are known as cócs, a word common to Terra Alta and the neighbouring districts of Ribera d'Ebre and the Priorat. Locally produced mistelle, sweet or rancid wine is served with the pastries. Nowadays, the bakeries and cake makers in the area's towns and villages also produce traditionally crafted products, that used only to be homemade.The article, resulting from the final degree project produced by the author for her Humanities degree at the UOC, offers a privileged look at the richness of the Terra Alta in terms of its gastronomic history, customs and its high regard for its cakes. The author, who has previous experience in the field, places the specific aspects of Terra Alta cake making in the context of the Mediterranean cultures with common roots dating back to the ancient and medieval worlds and which still have an easily identifiable "family feel", whilst looking, from an ethnographic point of view, at what she calls the "world of wheat" in the area, (the dough for bread, the craft of the baker, the ovens and other tools, and the associated traditions, among other things. In short, she rescues a living part of the local day-to-day activities and places it under the microscope of food history, whilst providing information that may well be of interest for study from other points of view.

  4. Terra MODIS Band 27 Electronic Crosstalk Effect and Its Removal

    Science.gov (United States)

    Sun, Junqiang; Xiong, Xiaoxiong; Madhavan, Sriharsha; Wenny, Brian

    2012-01-01

    The MODerate-resolution Imaging Spectroradiometer (MODIS) is one of the primary instruments in the NASA Earth Observing System (EOS). The first MODIS instrument was launched in December, 1999 on-board the Terra spacecraft. MODIS has 36 bands, covering a wavelength range from 0.4 micron to 14.4 micron. MODIS band 27 (6.72 micron) is a water vapor band, which is designed to be insensitive to Earth surface features. In recent Earth View (EV) images of Terra band 27, surface feature contamination is clearly seen and striping has become very pronounced. In this paper, it is shown that band 27 is impacted by electronic crosstalk from bands 28-30. An algorithm using a linear approximation is developed to correct the crosstalk effect. The crosstalk coefficients are derived from Terra MODIS lunar observations. They show that the crosstalk is strongly detector dependent and the crosstalk pattern has changed dramatically since launch. The crosstalk contributions are positive to the instrument response of band 27 early in the mission but became negative and much larger in magnitude at later stages of the mission for most detectors of the band. The algorithm is applied to both Black Body (BB) calibration and MODIS L1B products. With the crosstalk effect removed, the calibration coefficients of Terra MODIS band 27 derived from the BB show that the detector differences become smaller. With the algorithm applied to MODIS L1B products, the Earth surface features are significantly removed and the striping is substantially reduced in the images of the band. The approach developed in this report for removal of the electronic crosstalk effect can be applied to other MODIS bands if similar crosstalk behaviors occur.

  5. Validation of TERRA-ML with discharge measurements

    Directory of Open Access Journals (Sweden)

    René Grasselt

    2008-12-01

    Full Text Available We evaluate the runoff-simulation performance of a water transport model (routing scheme coupled to the Land Surface Parameterization module TERRA-ML of the operational COSMO (Consortium for Small-Scale Modelling weather forecast model. In addition to the successful implemention of the routing scheme, we also included an alternative vertical soil water transport parameterisation in TERRA-ML in order to estimate the uncertainty caused by the component of the LSP central to runoff generation. A combination of two data sets, both operational products by DWD, is used for precipitation input. These are the hourly precipitation data set RADOLAN RW, which is based on radar data and is calibrated by rain gauges, as well as the daily REGNIE data set, which is only based on gauge data. The mesoscale Sieg river catchment located in Western Germany is used as the evaluation testbed. The extended TERRA-ML was run in standalone mode (decoupled from the atmospheric part of the COSMO model with 1 × 1 km spatial resolution from April to September 2005 based on and provided with spatially more detailed descriptions of topography, land use and soil texture. The model was driven by operational COSMO analysis data and two different sources of observed precipitation (gauge and radar measurements. The results are compared to discharge measurements. They indicate a good representation of the observed discharge by the extended TERRA-ML system. The additionally implemented linear vertical soil water parameterization overestimates total discharge less (6 % than the default exponential parameterization (20 % when compared to a gauging station located at the lower reaches of the river Sieg. Suggestions are given on how to further enhance the modelled discharge by improvements in the LSP scheme.

  6. Geologic map of the Lada Terra quadrangle (V-56), Venus

    Science.gov (United States)

    Kumar, P. Senthil; Head, James W.

    2013-01-01

    This publication provides a geological map of Lada Terra quadrangle (V–56), a portion of the southern hemisphere of Venus that extends from lat 50° S. to 70° S. and from long 0° E. to 60° E. V–56 is bordered by Kaiwan Fluctus (V–44) and Agnesi (V–45) quadrangles in the north and by Mylitta Fluctus (V–61), Fredegonde (V–57), and Hurston (V–62) quadrangles in the west, east, and south, respectively. The geological map of V–56 quadrangle reveals evidence for tectonic, volcanic, and impact processes in Lada Terra in the form of tesserae, regional extensional belts, coronae, and volcanic plains. In addition, the map also shows relative age relations such as overlapping or cross-cutting relations between the mapped geologic units. The geology observed within this quadrangle addresses (1) how coronae evolved in association with regional extensional belts and (2) how tesserae, regional plains, and impact craters, which are also significant geological units observed in Lada Terra quadrangle, were formed.

  7. Mission Applications of a HIAD for the Mars Southern Highlands

    Science.gov (United States)

    Winski, Richard; Bose, Dave; Komar, David R.; Samareh, Jamshid

    2013-01-01

    Recent discoveries of evidence of a flowing liquid in craters throughout the Mars Southern Highlands, like Terra Sirenum, have spurred interest in sending science missions to those locations; however, these locations are at elevations that are much higher (0 to +4 km MOLA) than any previous landing site (-1 to -4 km MOLA). New technologies may be needed to achieve a landing at these sites with significant payload mass to the surface. A promising technology is the hypersonic inflatable aerodynamic decelerator (HIAD); a number of designs have been advanced but the stacked torus has been recently successfully flight tested in the IRVE-2 and IRVE-3 projects through the NASA Langley Research Center. This paper will focus on a variety of mission applications of the stacked torus type attached HIAD to the Mars southern highlands.

  8. Mars Gashopper Airplane Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Gas Hopper Airplane, or "gashopper" is a novel concept for propulsion of a robust Mars flight and surface exploration vehicle that utilizes indigenous CO2...

  9. Beyond water on Mars

    OpenAIRE

    Grotzinger, John

    2009-01-01

    Mars exploration has been guided by the search for water. The more complex quest by Mars Science Laboratory for habitable environments should illuminate the Martian environmental history, and possibly deliver insights into extraterrestrial life.

  10. Saltation transport on Mars.

    Science.gov (United States)

    Parteli, Eric J R; Herrmann, Hans J

    2007-05-11

    We present the first calculation of saltation transport and dune formation on Mars and compare it to real dunes. We find that the rate at which grains are entrained into saltation on Mars is 1 order of magnitude higher than on Earth. With this fundamental novel ingredient, we reproduce the size and different shapes of Mars dunes, and give an estimate for the wind velocity on Mars. PMID:17677662

  11. Saltation transport on Mars

    OpenAIRE

    Parteli, Eric J. R.; Herrmann, Hans J.

    2007-01-01

    We present the first calculation of saltation transport and dune formation on Mars and compare it to real dunes. We find that the rate at which grains are entrained into saltation on Mars is one order of magnitude higher than on Earth. With this fundamental novel ingredient, we reproduce the size and different shapes of Mars dunes, and give an estimate for the wind velocity on Mars.

  12. 基于TerraScan的LiDAR数据处理%LiDAR' Data Processing Based on TerraScan

    Institute of Scientific and Technical Information of China (English)

    黄金浪

    2007-01-01

    介绍LiDAR技术的国内外发展情况,围绕LiDAR数据后处理软件TerraScan的应用,详细论述该软件的数据处理流程,特别针对LiDAR数据特点和处理技术难点提出笔者的看法.

  13. Mars: 2010 - 2020

    Science.gov (United States)

    Li, Fuk K.

    2006-01-01

    This slide presentation reviews the Mars Exploration program for the current decade and beyond. The potential items for procurements for the Mars Science Laboratory (MSL) are discussed, as well as future technology investments to enable to continued development of exploration of Mars by rovers and orbiters that are planned and envisioned for future missions.

  14. Factors unflinching e-commerce adoption by retailers in Saudi Arabia: Qual Analysis

    OpenAIRE

    AlGhamdi, Rayed; Drew, Steve; Al-Ghaith, Waleed

    2012-01-01

    This paper presents the preliminary findings of a study researching the diffusion and the adoption of online retailing in Saudi Arabia. It reports new research that identifies and explores the key issues that positively and negatively influence retailers in Saudi Arabia regarding the adoption of electronic commerce. Retailers in Saudi Arabia have been reserved in their adoption of electronically delivered aspects of their business. Despite the fact that Saudi Arabia has the largest and fastes...

  15. Retrospective analysis of keratoconus at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia

    OpenAIRE

    Alabdelmoneam M

    2012-01-01

    Mussaed AlabdelmoneamFaculty of Applied Medical Sciences, Shaqra University, Shaqra University, Saudi ArabiaBackground: This work was a retrospective study undertaken in a tertiary eye care hospital to evaluate the putative prevalence and referral patterns for keratoconus by gender, age, and region of Saudi Arabia.Methods: Files from 1638 keratoconus patients from different regions of Saudi Arabia referred to King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia, between January 1999 and ...

  16. Terra Rossa in the Mediterranean Region: Parent Materials, Composition and Origin

    OpenAIRE

    Durn, G.

    2003-01-01

    In the past, the term “terra rossa” became quite a common indication for all limestone derived red soils in the Mediterranean region. Today, in some classification systems based on the Mediterranean climate as the major soil differentiating criterion, the term terra rossa is used as a name for the soil subclass “Modal Fersiallitic Red soil” when situated on limestones (Duchaufour, 1982). However, several national soil classifications (e.g. Croatian, Italian, Israeli) retained the term “terra ...

  17. Bulk and clay mineral composition indicate origin of terra rossa soils in Western Herzegovina

    OpenAIRE

    Durn, Goran; Ćorić, Radica; Tadej, Neven; Barudžija, Uroš; Rubinić, Vedran; Husnjak, Stjepan

    2014-01-01

    The B horizons of terra rossa soils developed on three different carbonate lithologies having variable insoluble residue contents were studied in Western Herzegovina. Comparison of  their composition and properties illustrates to what extent mineral (especially clay mineral assemblage) and particle size composition of those horizons and the insoluble residue of the underlying carbonate rocks can be used as indicators of the polygenetic nature of terra rossa in this region. Terra rossa B horiz...

  18. Pasolini, Marilyn e la partenza degli dei dalla terra

    OpenAIRE

    A. Bernardi

    2010-01-01

    Nella poesia che Pasolini aveva scritto per la morte di Marilyn Monroe, e che poi inserì nel film La rabbia (1963), letta dalla voce di Giorgio Bassani, l’autore fa rivivere un mito antichissimo, sulle orme di Ovidio e delle "Metamorfosi", Libro I: il mito di Astrea, la dea della giustizia che per ultima abbandonò la terra alla fine delle epoche felici dell’umanità, prima che Zeus mandasse il diluvio. Il saggio confronta i passi delle Metamorfosi con alcuni versi di Pasolini, individua somigl...

  19. Role of social media in brand development in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Abeer Abdullah Al Saud

    2013-01-01

    Full Text Available Literature is ripe with the scholarly contributions on brand development from all aspects. The new marketing tools and techniques are introduced frequently. However, the impact social media has had on brand development is no match to traditional promotion in 4Ps. The information about Saudi Arabia is specially rare. This article based on a survey of 200 social media users on www.surveymonkey.com evaluates the role of social media in brand development in Saudi Arabia. The results from this Saudi example show that social media including Facebook and Twitter are among the most effective tool to develop a brand as compared to traditional promotional methods. It has also been found that these media are more successful in Saudi Arabia to develop the brand recall and image.

  20. The need for national medical licensing examination in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Alzahrani Khalid

    2008-11-01

    Full Text Available Abstract Background Medical education in Saudi Arabia is facing multiple challenges, including the rapid increase in the number of medical schools over a short period of time, the influx of foreign medical graduates to work in Saudi Arabia, the award of scholarships to hundreds of students to study medicine in various countries, and the absence of published national guidelines for minimal acceptable competencies of a medical graduate. Discussion We are arguing for the need for a Saudi national medical licensing examination that consists of two parts: Part I (Written which tests the basic science and clinical knowledge and Part II (Objective Structured Clinical Examination which tests the clinical skills and attitudes. We propose this examination to be mandated as a licensure requirement for practicing medicine in Saudi Arabia. Conclusion The driving and hindering forces as well as the strengths and weaknesses of implementing the licensing examination are discussed in details in this debate.

  1. Rabies in Saudi Arabia: a need for epidemiological data

    Directory of Open Access Journals (Sweden)

    Ziad A. Memish

    2015-05-01

    Full Text Available Rabies is endemic in animals in the Arabian Peninsula. Although Saudi Arabia is the largest country in the Peninsula, little has been published about the rabies situation in the country. A total of 11 069 animal bites to humans were reported during 2007–2009, and 40 animals suspected of rabies were examined for rabies infection from 2005 through 2010. Results suggest that animal-related injuries in Saudi Arabia remain a public health problem, with feral dogs accounting for the majority of bites to humans and for the majority of animals found to be rabid. Over the last 10 years, no confirmed human rabies case has been reported. More detailed information about the epidemiology of animal bites and that of animal rabies in Saudi Arabia would be of great interest, notably to provide a basis on which vaccination recommendations could be made for the numerous international travellers visiting the country.

  2. Introducing SMART Table Technology in Saudi Arabia Education System

    Directory of Open Access Journals (Sweden)

    Gafar Almalki

    2013-03-01

    Full Text Available Education remains one of the most important economic development indicators in Saudi Arabia. This is evident in the continuous priority of the development and enhancement of education. The application of technology is crucial to the growth and improvement of the educational system in Saudi Arabia. Introducing SMART Table technology in the Saudi Arabian education system is argued in this paper as being able to assist teachers and students in the process of accommodating both technological changes and new knowledge. SMART Tables also can enhance the level of flexibility in the educational system, thus improving the quality of education within a modern Saudi Arabia. It is crucial to integrate technology effectively and efficiently within the educational system to improve the quality of student outcomes. This study will consider the potential benefits and recommendations associated with the adoption of SMART Tables in Saudi Arabian education system.

  3. Essays on oil and business cycles in Saudi Arabia

    Science.gov (United States)

    Aba Alkhail, Bandar A.

    This dissertation consists of three chapters. Chapter one presents a theoretical model using a dynamic stochastic general equilibrium (DSGE) approach to investigate the role of world oil prices in explaining the business cycle in Saudi Arabia. This model incorporates both productivity and oil revenue shocks. The results indicate that productivity shocks are relatively more important to business cycles than oil shocks. However, this model has some unfavorable features that are associated with both investment and labor hours. The second chapter presents a modified theoretical model using DSGE approach to examine the role of world oil prices versus productivity shocks in explaining the business cycles in Saudi Arabia. To overcome the unfavorable features of the baseline model, the alternative model adds friction to the model by incorporating investment portfolio adjustment cost. Thus, the alternative model produces similar dynamics to that of the baseline model but the unfavorable characteristics are eliminated. Also, this chapter conducts sensitivity analysis. The objective of the third chapter is to empirically investigate how real world oil price and productivity shocks affect output, consumption, investment, labor hours, and trade balance/output ratio for Saudi Arabia. This chapter complements the theoretical model of the previous chapters. In addition, this study builds a foundation for future studies in examining the impact of real world oil price shocks on the economies of key trade partners of Saudi Arabia. The results of the third chapter show that productivity shocks matter more for macroeconomic fluctuations than oil shocks for the Saudis' primary trade partners. Therefore, fears of oil importing countries appear to be overstated. As a whole, this research is important for the following reasons. First, the empirical model is consistent with the predictions of our theoretical model in that productivity is a driving force of business cycles in Saudi Arabia

  4. Fruit and vegetable consumption among adults in Saudi Arabia, 2013

    OpenAIRE

    Mokdad, Ali

    2015-01-01

    Charbel El Bcheraoui,1 Mohammed Basulaiman,2 Mohammad A AlMazroa,2 Marwa Tuffaha,1 Farah Daoud,1 Shelley Wilson,1 Mohammad Y Al Saeedi,2 Faisal M Alanazi,2 Mohamed E Ibrahim,2 Elawad M Ahmed,2 Syed A Hussain,2 Riad M Salloum,2 Omer Abid,2 Mishal F Al-Dossary,2 Ziad A Memish,2 Abdullah A Al Rabeeah,2 Ali H Mokdad1 1Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA; 2Ministry of Health of the Kingdom of Saudi Arabia, Riyadh, Saudi Arabia Background: Dietar...

  5. CRISM's Global Mapping of Mars, Part 2

    Science.gov (United States)

    2007-01-01

    tiles just delivered to the PDS. It shows a part of the planet called Tyrrhena Terra in the ancient, heavily cratered highlands. The colored strips are CRISM multispectral survey data acquired over several months, in which each pixel has a calibrated 72-color spectrum of Mars. The three wavelengths shown are 2.53, 1.50, and 1.08 micrometers in the red, green, and blue image planes respectively. At these wavelengths, rocky areas appear brown, dusty areas appear tan, and regions with hazy atmosphere appear bluish. Note that there is a large difference in brightness between strips, because there is no correction for the lighting conditions at the time of each observation. The gray areas between the strips are from an earlier mosaic of the planet taken by the Thermal Emission Imaging System (THEMIS) instrument on Mars Odyssey, and are included only for context. Ultimately the multispectral survey will cover nearly all of this area. CRISM is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter and the Mars Science Laboratory for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter.

  6. CRISM's Global Mapping of Mars, Part 1

    Science.gov (United States)

    2007-01-01

    tiles just delivered to the PDS. It shows a part of the planet called Tyrrhena Terra in the ancient, heavily cratered highlands. The colored strips are CRISM multispectral survey data acquired over several months, in which each pixel has a calibrated 72-color spectrum of Mars. The three wavelengths shown are 2.53, 1.50, and 1.08 micrometers in the red, green, and blue image planes respectively. At these wavelengths, rocky areas appear brown, dusty areas appear tan, and regions with hazy atmosphere appear bluish. Note that there is a large difference in brightness between strips, because there is no correction for the lighting conditions at the time of each observation. The gray areas between the strips are from an earlier mosaic of the planet taken by the Thermal Emission Imaging System (THEMIS) instrument on Mars Odyssey, and are included only for context. Ultimately the multispectral survey will cover nearly all of this area. CRISM is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter and the Mars Science Laboratory for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter.

  7. The crosstalk of telomere dysfunction and inflammation through cell-free TERRA containing exosomes.

    Science.gov (United States)

    Wang, Zhuo; Lieberman, Paul M

    2016-08-01

    Telomeric repeats-containing RNA (TERRA) are telomere-derived non-coding RNAs that contribute to telomere function in protecting chromosome ends. We recently identified a cell-free form of TERRA (cfTERRA) enriched in extracellular exosomes. These cfTERRA-containing exosomes stimulate inflammatory cytokines when incubated with immune responsive cells. Here, we report that cfTERRA levels were increased in exosomes during telomere dysfunction induced by the expression of the dominant negative TRF2. The exosomes from these damaged cells also enriched with DNA damage marker γH2AX and fragmented telomere repeat DNA. Purified cfTERRA stimulated inflammatory cytokines, but the intact membrane-associated nucleoprotein complexes produced a more robust cytokine activation. Therefore, we propose cfTERRA-containing exosomes transport a telomere-associated molecular pattern (TAMP) and telomere-specific alarmin from dysfunctional telomeres to the extracellular environment to elicit an inflammatory response. Since cfTERRA can be readily detected in human serum it may provide a useful biomarker for the detection of telomere dysfunction in the early stage of cancers and aging-associated inflammatory disease.

  8. EPA SITE DEMONSTRATION OF THE TERRA VAC IN SITU VACUUM EXTRACTION PROCESS IN GROVELAND, MASSACHUSETTS

    Science.gov (United States)

    This paper presents an EPA evaluation of the patented Terra Vac, Inc.'s in situ vacuum extraction process that was field-demonstrated on a trichloroethylene (TCE) contaminated soil in Groveland, MA, under the EPA Superfund Innovative Technology Evaluation (SITE) program. he Terra...

  9. Identification of TERRA locus unveils a telomere protection role through association to nearly all chromosomes.

    Science.gov (United States)

    López de Silanes, Isabel; Graña, Osvaldo; De Bonis, Maria Luigia; Dominguez, Orlando; Pisano, David G; Blasco, Maria A

    2014-01-01

    Telomeric RNAs (TERRAs) are UUAGGG repeat-containing RNAs that are transcribed from the subtelomere towards the telomere. The precise genomic origin of TERRA has remained elusive. Using a whole-genome RNA-sequencing approach, we identify novel mouse transcripts arising mainly from the subtelomere of chromosome 18, and to a lesser extend chromosome 9, that resemble TERRA in several key aspects. Those transcripts contain UUAGGG-repeats and are heterogeneous in size, fluctuate in abundance in a TERRA-like manner during the cell cycle, are bound by TERRA RNA-binding proteins and are regulated in a manner similar to TERRA in response to stress and the induction of pluripotency. These transcripts are also found to associate with nearly all chromosome ends and downregulation of the transcripts that originate from chromosome 18 causes a reduction in TERRA abundance. Interestingly, downregulation of either chromosome 18 transcripts or TERRA results in increased number of telomere dysfunction-induced foci, suggesting a protective role at telomeres.

  10. Terra-Kleen Response Group, Inc. Solvent Extraction Technology Rapid Commercialization Initiative Report

    Science.gov (United States)

    Terra-Kleen Response Group Inc. (Terra-Kleen), has commercialized a solvent extraction technology that uses a proprietary extraction solvent to transfer organic constituents from soil to a liquid phase in a batch process at ambient temperatures. The proprietary solvent has a rel...

  11. Status of Terra MODIS Operation, Calibration, and Performance

    Science.gov (United States)

    Xiong, X.; Wenny, B.; Wu, A.; Angal, A.; Geng, X.; Chen, H.; Dodd, J.; Link, D.; Madhavan, S.; Chen, N.; Li, Y.; Iacangelo, S.; Barnes, W.; Salomonson, V.

    2014-01-01

    Since launch in December 1999, Terra MODIS has successfully operated for nearly 15 years, making continuous observations. Data products derived from MODIS observations have significantly contributed to a wide range of studies of key geophysical parameters of the earth's eco-system of land, ocean, and atmosphere, and their changes over time. The quality of MODIS data products relies on the dedicated effort to monitor and sustain instrument health and operation, to calibrate and update sensor parameters and properties, and to improve calibration algorithms. MODIS observations are made in 36 spectral bands, covering wavelengths from visible to long-wave infrared. The reflective solar bands (1-19 and 26) are primarily calibrated by a solar diffuser (SD) panel and regularly scheduled lunar observations. The thermal emissive bands (20-25 and 27- 36) calibration is referenced to an on-board blackbody (BB) source. On-orbit changes in the sensor spectral and spatial characteristics are monitored by a spectroradiometric calibration assembly (SRCA). This paper provides an overview of Terra MODIS on-orbit operation and calibration activities and implementation strategies. It presents and summarizes sensor on-orbit performance using nearly 15 years of data from its telemetry, on-board calibrators, and lunar observations. Also discussed in this paper are changes in sensor characteristics, corrections applied to maintain MODIS level 1B (L1B) data quality, and efforts for future improvements.

  12. Why did Arabia separate from Africa ?

    Science.gov (United States)

    Bellahsen, N.; Faccenna, C.; Funiciello, F.; Daniel, J. M.; Jolivet, L.

    2003-04-01

    We have performed 3-D scaled lithospheric experiments to investigate the role of the gravitational force exerted by subduction slab on the deformation of the subducting plate itself. Experiments have been constructed using a dense silicone putty plate, to simulate a thin viscous lithosphere, floated in glucose syrup, simulating the upper mantle. We show different plate configuration: (i) subduction of a uniform oceanic plate, (ii) subduction of oceanic-continental plate system, and (iii) subduction of a more complex oceanic-continental system simulating the asymmetric Africa-Eurasia system at the beginning of the Tertiary. Each model has been performed including or not the presence of circular weak zone inside the subducting plate simulating the near-surface weakening effect of a plume activity. Our results show that a subducting plate can deform in its interior only if the velocity field generated by the slab varies laterally along the subduction zone, i.e. by the asymmetrical entrance of continental material at trench. The result of this study can be used to analyze the formation of the Arabian plate. We found that intraplate stresses, similar to the one that generated the Africa-Arabia break-up, can be related to the Neogene evolution of the northern convergent margin of the African plate where a lateral change from collision (Mediterranean and Bitlis) to active subduction (Makran) has been described. Second, intraplate stress and strain localization are favored by the presence of a weakness zone, such as the one generated by the Afar plume, producing a pattern of extensional deformation belts resembling to the Red Sea-Gulf of Aden rift system.

  13. Attitude to blood donation in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Abdel Gader Abdel Galil

    2011-01-01

    Full Text Available Background and Objectives: The blood donor system in the Kingdom of Saudi Arabia depends on a combination of voluntary and involuntary donors. The aim of this study is to explore the attitudes, beliefs and motivations of Saudis toward blood donation. Materials and Methods: The study was conducted at the Donor Centers at King Khalid University Hospital (KKUH Blood Bank and King Saud University Students Health Center, Riyadh. A self-administered questionnaire was distributed to donors (n = 517 and nondonors (n = 316, between February and June 2008. All were males. Results: Ninety-nine percent of the respondents showed positive attitude toward blood donations and its importance for patients care, and object the importation of blood from abroad. Blood donors: Ninety-one percent agree that that blood donation is a religious obligation, 91% think no compensation should be given, 63% will accept a token gift, 34% do not object to donating six times/year and 67% did not mind coming themselves to the donor center to give blood. Nondonors: Forty-six percent were not asked to give blood and those who were asked mentioned fear (5% and lack of time (16% as their main deterrents. Reasons for rejection as donors include underweight and age (71% and health reasons (19%. Seventy-five percent objected to money compensation but 69% will accept token gifts and 92% will donate if a relative/friend needs blood. Conclusion: These results reflect an encouraging strong positive attitude toward blood donation. Further future planning with emphasis on educational/publicity programs and careful organization of donor recruitment campaigns could see the dream of total voluntary nonremunerated blood donations should not take long to be true.

  14. Mars at Opposition

    Science.gov (United States)

    Riddle, Bob

    2010-01-01

    On January 29, Mars will reach opposition, a point along its orbit around the Sun where Mars will be directly opposite from the Sun in a two-planet and Sun line-up with the Earth in between. At this opposition, the Earth and Mars will be separated by nearly 100 million km. An opposition is similar to a full Moon in that the planet at opposition…

  15. Preliminary study of provenance and firing style of terra-cotta from Qinshihuang mausoleum

    International Nuclear Information System (INIS)

    Petrographic analyses of the shards of terra-cotta from Qinshihuang Mausoleum showed that the terra-cotta was made of sand-tempered pottery. Pure clay samples should be obtained from pottery body using a special method to remove the tempered sand. Both pure clay and soil samples from the area of Mountain Li were analyzed by ICP-AES, and then the composition data were handled with cluster analysis. Its result supported the conjecture that the material of terra-cotta was from Mountain Li area. The firing temperature of 4 shards of terra-cotta suggested that not every terra-cotta was made in the kiln, some individual might be made in the open air

  16. Digital cartography of Mars

    Science.gov (United States)

    Batson, R. M.

    1987-01-01

    A medium-resolution Digital Image Model (DIM) of Mars is being compiled. A DIM is a mosaic of radiometrically corrected, photometrically modelled spacecraft images displaying accurate reflectance properties at uniform resolution, and geometrically tied to the best available control. The Mars medium-resolution DIM contains approximately 4700 Viking Orbiter image frames that were used to compile the recently completed 1:2,000,000-scale controlled photomosaic series of Mars. This DIM provides a planimetric control base to which all other Mars maps will be registered. A similar control base of topographic elevations (Digital Terrain Model, or DTM) is also being compiled. These products are scheduled for completion in 1989.

  17. Mars Museum Visualization Alliance

    Science.gov (United States)

    Sohus, A. M.; Viotti, M. A.; de Jong, E. M.

    2004-11-01

    The Mars Museum Visualization Alliance is a collaborative effort funded by the Mars Public Engagement Office and supported by JPL's Informal Education staff and the Solar System Visualization Project to share the adventure of exploration and make Mars a real place. The effort started in 2002 with a small working group of museum professionals to learn how best to serve museum audiences through informal science educators. By the time the Mars Exploration Rovers landed on Mars in January 2004, over 100 organizations were partners in the Alliance, which has become a focused community of Mars educators. The Alliance provides guaranteed access to images, information, news, and resources for use by the informal science educators with their students, educators, and public audiences. Thousands of people have shared the adventure of exploring Mars and now see it as a real place through the efforts of the Mars Museum Visualization Alliance partners. The Alliance has been lauded for "providing just the right inside track for museums to do what they do best," be that webcasts, live presentations with the latest images and information, high-definition productions, planetarium shows, or hands-on educational activities. The Alliance is extending its mission component with Cassini, Genesis, Deep Impact, and Stardust. The Mars Exploration and Cassini Programs, as well as the Genesis, Deep Impact, and Stardust Projects, are managed for NASA by the Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California.

  18. Mars Stratigraphy Mission

    Science.gov (United States)

    Budney, C. J.; Miller, S. L.; Cutts, J. A.

    2000-01-01

    The Mars Stratigraphy Mission lands a rover on the surface of Mars which descends down a cliff in Valles Marineris to study the stratigraphy. The rover carries a unique complement of instruments to analyze and age-date materials encountered during descent past 2 km of strata. The science objective for the Mars Stratigraphy Mission is to identify the geologic history of the layered deposits in the Valles Marineris region of Mars. This includes constraining the time interval for formation of these deposits by measuring the ages of various layers and determining the origin of the deposits (volcanic or sedimentary) by measuring their composition and imaging their morphology.

  19. Exobiology and Future Mars Missions

    Science.gov (United States)

    Mckay, Christopher P. (Editor); Davis, Wanda, L. (Editor)

    1989-01-01

    Scientific questions associated with exobiology on Mars were considered and how these questions should be addressed on future Mars missions was determined. The mission that provided a focus for discussions was the Mars Rover/Sample Return Mission.

  20. Meteorological impact of realistic Terra Nova Bay polynyas.

    Science.gov (United States)

    Morelli, Sandra

    2010-05-01

    The energy exchange between the ocean and the atmosphere in the Antarctic marginal sea ice zone is influenced by the extent of sea-ice cover. In areas of open water, a direct contact is established and intense energy exchanges occur, due to the large difference of temperature between the water and the air above it. This implies that the polynyas are areas where the ocean exchanges energy with the atmosphere and as a result they have an effect on the polar meteorology/climate. The work presented here concerns real polynya events in the region of Terra Nova Bay (TNB), Antarctica, where a recurring coastal polynya occurs nearby the Italian Antarctic Base. The aim is the study of the impact of polynyas on the atmosphere by three-dimensional numerical simulations. The ETA model (Mesinger et al., 2006) was used and ECMWF and NCEP data provided the initial and boundary conditions. The model had already been successfully used in the Antarctic area (Casini and Morelli, 2007) A polynya of realistic size (as observed by satellite image) was included in the initial conditions for the simulations and a study of the air circulation during the events is found in Morelli et al. (2007), Morelli and Casini (2008), Morelli et al. (2009). The Eta Model reproduced the evolution of upper and mod-level conditions in good agreement with AVHRR observations (Morelli, 2008, Morelli and Parmiggiani, 2009). Also, the simulated 10 m wind was well correlated with the observed extension of the polynya. In order to isolate the effect of the presence of the open water area on the structure of the atmospheric boundary layer and on the atmospheric circulation, further simulations were performed without the presence of the polynya, i.e. with its extent covered with sea ice. The numerical simulations show that the polynyas act to increase the speed of the air above them and generate strong heat fluxes that warm the air. The effects are found over and downwind the sea ice free area. Results from the Eta

  1. Exploring Pedagogical Leadership in Early Years Education in Saudi Arabia

    Science.gov (United States)

    Alameen, Lubna; Male, Trevor; Palaiologou, Ioanna

    2015-01-01

    The empirical research for this paper was undertaken with leaders of early years setting in the Kingdom of Saudi Arabia (KSA). The investigation sought to establish to what extent it was possible to behave in line with the concept of pedagogical leadership in the twenty-first century in an Arab Muslim monarchy, dominated by Islam, where directive…

  2. Foreign Language Planning in Saudi Arabia: Beyond English

    Science.gov (United States)

    Payne, Mark; Almansour, Maram

    2014-01-01

    This paper presents findings from an exploratory study of foreign language planning in Saudi Arabia. In terms of official policy, the sole foreign language taught in Saudi public schools is English. Therefore, researching foreign languages there is often limited to researching the area of English as a Foreign Language. However, evidence shows that…

  3. Novel Gentic Variations Contributing to Asthma Susceptability in Saudi Arabia

    Science.gov (United States)

    2014-04-13

    Collection of Clinical Data That Will be Used in This Study and Will Form a Data Bank for Asthma in Saudi Arabia; Identify Known and NOVEL Genetic Risk Factors Contributing to Asthma Susceptibility; Study the Mechanistic Roles of the Genetic Variants Within Major Asthma Susceptibility Genes

  4. 75 FR 21598 - Energy and Infrastructure Mission to Saudi Arabia

    Science.gov (United States)

    2010-04-26

    ... its Master Gas System, building an NGL recovery plant, a new grass-roots gas plant, and enhancing capacity at an existing plant. While the global recession that began in 2008 has presented new economic... architecture, engineering, design and construction firms. Saudi Arabia's transport sector--including...

  5. University Teacher Educators' Research Engagement: Perspectives from Saudi Arabia

    Science.gov (United States)

    Borg, Simon; Alshumaimeri, Yousif

    2012-01-01

    This paper examines university teacher educators' engagement with and in educational research. Survey results collected from eighty-two teacher educators at a leading university in Saudi Arabia pointed to modest levels of research activity and also suggested that these individuals held largely technical views of what research is. Their assessments…

  6. Aetiology of Neonatal Septicaemia in Qatif, Saudi Arabia.

    Science.gov (United States)

    Elbashier, Ali M.; And Others

    1994-01-01

    Of the 1,797 babies admitted to a hospital in Saudi Arabia over a 3-year period, 8% were documented as having NNS. Identified several gram-positive bacteria, several gram-negative bacteria, and candida albicans as etiological agents in the cases of NNS. Determined the antibiotic susceptibility of the bacteria. (BC)

  7. Perspectives of petroleum and petrochemical industry in Saudi Arabia

    International Nuclear Information System (INIS)

    With the actual development of petroleum and petrochemical industry it is obvious that Saudi Arabia goes on to take an important place on the worldwide market; with its part in world reserves but with its determination to keep its place of first world exporter. From the point of view of its petroleum production, financial constraints can delay its expansion

  8. Geomatics Education in Saudi Arabia: Status, Challenges and Prospects

    Science.gov (United States)

    Aina, Yusuf Adedoyin

    2009-01-01

    Geospatial technology has been identified as one of the three most important emerging fields along with nanotechnology and biotechnology. The application of the technology is expected to grow and become more diversified in the coming years. In Saudi Arabia, the utilization of geotechnology is growing but still limited compared to the Western…

  9. Investigating Difficulties of Learning Computer Programming in Saudi Arabia

    Science.gov (United States)

    Alakeel, Ali M.

    2015-01-01

    Learning computer programming is one of the main requirements of many educational study plans in higher education. Research has shown that many students face difficulties acquiring reasonable programming skills during their first year of college. In Saudi Arabia, there are twenty-three state-owned universities scattered around the country that…

  10. 75 FR 54300 - Energy and Infrastructure Mission to Saudi Arabia

    Science.gov (United States)

    2010-09-07

    ... Information and Communication Technologies (ICT) trade mission to the Kingdom of Saudi Arabia, April 2-5, 2011... representatives from a variety of U.S. ICT industry suppliers and service providers. This trade mission will...'s primary ICT hubs. Trade mission participants will have the opportunity to interact with...

  11. Lactase persistence variants in Arabia and in the African Arabs.

    Science.gov (United States)

    Priehodová, Edita; Abdelsawy, Abdelhay; Heyer, Evelyne; Cerný, Viktor

    2014-01-01

    Lactase persistence (LP), the state enabling the digestion of milk sugar in adulthood, occurs only in some human populations. The convergent and independent origin of this physiological ability in Europe and Africa is linked with animal domestication that either had started in both places independently or had spread from the Near East by acculturation. However, it has recently been shown that at least in its southern parts, the population of Arabia not only has a different LP-associated mutation profile than the rest of Africa and Europe but also had experienced an independent demographic expansion occurring before the Neolithic around the Pleistocene-Holocene boundary. In Arabia, LP is associated with mutation -13,915*G and not, as in Europe, with -13,910*T or, as in Africa, with -13,907*G and -14,010*C. We show here that, in Arabia, -13,915*G frequency conforms to a partial clinal pattern and that this specific mutation has likely been spread from Arabia to Africa only recently from the sixth century AD onward by nomadic Arabs (Bedouins) looking for new pastures. Arabic populations in Africa that still maintain a nomadic way of life also have more -13,915*G variants and fewer sub-Saharan L-type mitochondrial DNA haplogroups; this observation matches archaeological and historical records suggesting that the migration of Arabic pastoralists was accompanied by gradual sedentarization that allowed for admixture with the local African population.

  12. Transition to knowledge-based economy in Saudi Arabia

    NARCIS (Netherlands)

    Nour, S.

    2014-01-01

    This paper discusses the progress in transition to knowledge-based economy in Saudi Arabia. As for the methodology, this paper uses updated secondary data obtained from different sources. It uses both descriptive and comparative approaches and uses the OECD definition of knowledge-based economy and

  13. Measuring the Climate of Training in Saudi Arabia.

    Science.gov (United States)

    Spicer, Richard G.

    1981-01-01

    One practitioner's experience in setting up on-the-job training in Saudi Arabia is described, including training materials, cultural environment, and the Saudi work ethic. In a related article, off-duty life for Americans is discussed, including dress for women and men, cultural aspects, and entertainment. (CT)

  14. Libraries of Two Women's Colleges in Saudi Arabia.

    Science.gov (United States)

    King, Elizabeth J.

    1987-01-01

    Describes the current status of higher education for women in Saudi Arabia and discusses the special problems of access to library materials encountered by women in this society, focusing on the collections, services, and administration of two women's colleges' libraries. A proposed national educational development plan is briefly described. (CLB)

  15. Islam's Point of View on Women's Education in Saudi Arabia.

    Science.gov (United States)

    Al-Hariri, Rafeda

    1987-01-01

    Shows links between Islamic doctrine and girls' education in Saudi Arabia providing examples of ways in which the Islamic attitude towards women and social life is applied to educational policy. Summarizes educational opportunities available for girls and women and notes milestones in the 26-year history of girls' education. (JHZ)

  16. Microscope on Mars

    Science.gov (United States)

    2004-01-01

    This image taken at Meridiani Planum, Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's microscopic imager (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  17. Genetic stratigraphy of key demographic events in Arabia.

    Science.gov (United States)

    Fernandes, Verónica; Triska, Petr; Pereira, Joana B; Alshamali, Farida; Rito, Teresa; Machado, Alison; Fajkošová, Zuzana; Cavadas, Bruno; Černý, Viktor; Soares, Pedro; Richards, Martin B; Pereira, Luísa

    2015-01-01

    At the crossroads between Africa and Eurasia, Arabia is necessarily a melting pot, its peoples enriched by successive gene flow over the generations. Estimating the timing and impact of these multiple migrations are important steps in reconstructing the key demographic events in the human history. However, current methods based on genome-wide information identify admixture events inefficiently, tending to estimate only the more recent ages, as here in the case of admixture events across the Red Sea (~8-37 generations for African input into Arabia, and 30-90 generations for "back-to-Africa" migrations). An mtDNA-based founder analysis, corroborated by detailed analysis of the whole-mtDNA genome, affords an alternative means by which to identify, date and quantify multiple migration events at greater time depths, across the full range of modern human history, albeit for the maternal line of descent only. In Arabia, this approach enables us to infer several major pulses of dispersal between the Near East and Arabia, most likely via the Gulf corridor. Although some relict lineages survive in Arabia from the time of the out-of-Africa dispersal, 60 ka, the major episodes in the peopling of the Peninsula took place from north to south in the Late Glacial and, to a lesser extent, the immediate post-glacial/Neolithic. Exchanges across the Red Sea were mainly due to the Arab slave trade and maritime dominance (from ~2.5 ka to very recent times), but had already begun by the early Holocene, fuelled by the establishment of maritime networks since ~8 ka. The main "back-to-Africa" migrations, again undetected by genome-wide dating analyses, occurred in the Late Glacial period for introductions into eastern Africa, whilst the Neolithic was more significant for migrations towards North Africa. PMID:25738654

  18. Summary of Aqua, Aura, and Terra High Interest Events

    Science.gov (United States)

    Newman, Lauri

    2015-01-01

    Single-obs tracking Sparsely tracked objects are an unfortunate reality of CARA operations Terra vs. 32081: new track with bad data was included in OD solution for secondary object and risk became high CARA and JSpOC discussed tracking and OSAs threw out the bad data. Event no longer presented high risk based on new OD Improvement: CARA now sends JSpOC a flag indicating when a single obs is included, so OSAs can evaluate if manual update to OD is required. Missing ASW OCMsAura vs. 87178, TCA: 317 at 08:04 UTC. Post-maneuver risk (conjunction was identified in OO results)CARA confirmed with JSpOC that ASW OCMs should have been received in addition to OO OCMsJSpOC corrected the manual error in their script that prevented the data from being delivered to CARAJSpOC QAd their other scripts to ensure this error did not exist in other places.

  19. Ionosphere of Mars observed by Mars Express.

    Science.gov (United States)

    Dubinin, Eduard; Fraenz, Markus; Andrews, Dave; Morgan, Dave

    2016-04-01

    The Martian ionosphere is studied at different solar zenith angles using the local electron number densities and total electron content (TEC) derived from the observations by MARSIS onboard Mars Express. The data are complemented by the ASPERA-3 observations which provide us with the information about upward/downward velocity of the low-energy ions and electron precipitation. We consider the Mars Express observations at different solar cycle intervals. Different factors which influence the ionosphere dynamics are analyzed. The focus is made on a role of the crustal magnetic field on the Martian ionosphere and its influence on ion escape.

  20. Accuracy assessment of Terra-MODIS aerosol optical depth retrievals

    International Nuclear Information System (INIS)

    Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol products have been widely used to address environment and climate change subjects with daily global coverage. Aerosol optical depth (AOD) is retrieved by different algorithms based on the pixel surface, determining between land and ocean. MODIS-Terra and Global Aerosol Robotic Network (AERONET) products can be obtained from the Multi-sensor Aerosol Products Sampling System (MAPSS) for coastal regions during 2000-2010. Using data collected from 83 coastal stations worldwide from AERONET from 2000-2010, accuracy assessments are made for coastal aerosol optical depth (AOD) retrieved from MODIS aboard the Terra satellite. AOD retrieved from MODIS at 0.55μm wavelength has been compared With the AERONET derived AOD, because it is reliable with the major wavelength used by many chemistry transport and climate models as well as previous MODIS validation studies. After removing retrievals with quality flags below1 for Ocean algorithm and below 3 for Land algorithm, The accuracy of AOD retrieved from MODIS Dark Target Ocean algorithms (correlation coefficient R2 is 0.844 and a regression equation of τM = 0.91·τA + 0.02 (where subscripts M and A represent MODIS and AERONET respectively), is the greater than the MODIS Dark Target Land algorithms (correlation coefficient R2 is 0.764 and τM = 0.95·τA + 0.03) and the Deep Blue algorithm (correlation coefficient R2 is 0.652 and τM = 0.81·τA + 0.04). The reasons of the retrieval error in AOD are found to be the various underlying surface reflectance. Therefore, the aerosol models and underlying surface reflectance are the dominant factors which influence the accuracy of MODIS retrieval performance. Generally the MODIS Land algorithm implements better than the Ocean algorithm for coastal sites

  1. Probing Mars’ atmosphere with ExoMars Mars Climate Sounder

    OpenAIRE

    Irwin, Patrick G. J.; Calcutt, S.B.; P. L. Read; Bowles, N E; Lewis, S

    2011-01-01

    The 2016 Mars Trace Gas Mission will carry with it the ExoMars Mars Climate Sounder instrument, a development of the very successful Mars Climate Sounder instrument already in orbit about Mars on NASA's Mars Reconnaissance Orbiter spacecraft. EMCS will continue the monitoring of Mars global temperature/pressure/aerosol field, and will also be able to measure the vertical profile of water vapour across the planet from 0 – 50 km. Key components of EMCS will be provided by Oxford, Reading and Ca...

  2. ExoMars 2016 arrives at Mars

    Science.gov (United States)

    Svedhem, Hakan; Vago, Jorge L.; ExoMars Team

    2016-10-01

    The Trace Gas Orbiter (TGO) and the Schiaparelli Entry, descent and landing Demonstrator Model (EDM) will arrive at Mars on 19 October 2016. The TGO and the EDM are part of the first step of the ExoMars Programme. They will be followed by a Rover and a long lived Surface Platform to be launched in 2020.The EDM is attached to the TGO for the full duration of the cruise to Mars and will be separated three days before arrival at Mars. After separation the TGO will perform a deflection manoeuvre and, on 19 October (during the EDM landing), enter into a highly elliptical near equatorial orbit. TGO will remain in this parking orbit until January 2017, when the orbital plane inclination will be changed to 74 degrees and aerobraking to the final 400 km near circular orbit will start. The final operational orbit is expected to be reached at the end of 2017.The TGO scientific payload consists of four instruments. These are: ACS and NOMAD, both infrared spectrometers for atmospheric measurements in solar occultation mode and in nadir mode, CASSIS, a multichannel camera with stereo imaging capability, and FREND, an epithermal neutron detector for search of subsurface hydrogen. The mass of the TGO is 3700 kg, including fuel. The EDM, with a mass of 600 kg, is mounted on top of the TGO as seen in its launch configuration. The main objective of the EDM is to demonstrate the capability of performing a safe entry, descent and landing on the surface, but it does carry a descent camera and a small battery powered meteorological package that may operate for a few days on the surface.The ExoMars programme is a joint activity by the European Space Agency(ESA) and ROSCOSMOS, Russia. ESA is providing the TGO spacecraft and Schiaparelli (EDM) and two of the TGO instruments and ROSCOSMOS is providing the launcher and the other two TGO instruments. After the arrival of the ExoMars 2020 mission at the surface of Mars, the TGO will handle the communication between the Earth and the Rover and

  3. A qualitative exploration of the major challenges facing pharmacovigilance in Saudi Arabia

    OpenAIRE

    2015-01-01

    Objectives: To explore the challenges facing pharmacovigilance in Saudi Arabia and formulate recommendations to improve it from the perspective of healthcare professionals in Saudi Arabia. Methods: This was a qualitative study of 4 focus group discussions with pharmacists, physicians, and academicians held under the auspices of the King Saud University School of Pharmacy and the Center for Medicine in the Public Interest, Riyadh, Saudi Arabia. A total of 29 eligible healthcare professionals w...

  4. Evaluation of Different Soil Salinity Mapping Using Remote Sensing Techniques in Arid Ecosystems, Saudi Arabia

    OpenAIRE

    Mohamed Elhag

    2016-01-01

    Land covers in Saudi Arabia are generally described as salty soils with sand dunes and sand sheets. Waterlogging and higher soil salinity are major challenges to sustaining agricultural practices in Saudi Arabia principally within closed drainage basins. Agricultural practices in Saudi Arabia were flourishing in the last two decades. The newly reclaimed lands were added annually and distributed all over the country. Irrigation techniques are mostly modernized to fulfill water saving strategie...

  5. Driving online shopping: Spending and behavioral differences among women in Saudi Arabia

    OpenAIRE

    Al-maghrabi, T; Dennis, C.

    2009-01-01

    This study proposes a revised technology acceptance model that integrates expectation confirmation theory to measure gender differences with regard to continuance online shopping intentions in Saudi Arabia. The sample consists of 650 female respondents. A structural equation model confirms model fit. Perceived enjoyment, usefulness, and subjective norms are determinants of online shopping continuance in Saudi Arabia. High and low online spenders among women in Saudi Arabia are equivalent. The...

  6. Exobiology on Mars

    Science.gov (United States)

    Devincenzi, D. L. (Editor); Marshall, J. R. (Editor); Andersen, D. (Editor)

    1990-01-01

    Descriptions of several instrument concepts that were generated during a workshop entitled, Exobiology Instrument Concepts for a Soviet Mars 94/94 Mission, held at NASA Ames Research Center in 1989 are presented. The objective was to define and describe instrument concepts for exobiology and related science that would be compatible with the mission types under discussion for the 1994 and 1996 Soviet Mars missions. Experiments that use existing technology were emphasized. The concepts discussed could also be used on U.S. missions that follow Mars Observer.

  7. SST, Terra MODIS, NPP, 0.05 degrees, Global, Nighttime (4 microns), Science Quality

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch provides SST data from NASA's Terra Spacecraft. Measurements are gathered by the Moderate Resolution Imaging Spectroradiometer (MODIS) carried...

  8. SST, Terra MODIS, NPP, 0.05 degrees, Global, Daytime, Science Quality

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch provides SST data from NASA's Terra Spacecraft. Measurements are gathered by the Moderate Resolution Imaging Spectroradiometer (MODIS) carried...

  9. Chlorophyll-a, Terra MODIS, OSU DB, 0.0125 degrees, West US, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration data from NASA's Terra satellite. Measurements are gathered by the Moderate Resolution Imaging...

  10. Retrieval of Aerosol Properties from MODIS Terra, MODIS Aqua, and VIIRS SNPP: Calibration Focus

    Science.gov (United States)

    Levy, Robert C.; Mattoo, Shana; Sawyer, Virginia; Kleidman, Richard; Patadia, Falguni; Zhou, Yaping; Gupta, Pawan; Shi, Yingxi; Remer, Lorraine; Holz, Robert

    2016-01-01

    MODIS-DT Collection 6 - Aqua/Terra level 2, 3; entire record processed - "Trending" issues reduced - Still a 15% or 0.02 Terra vs Aqua offset. - Terra/Aqua convergence improved with C6+, but bias remains. - Other calibration efforts yield mixed results. VIIRS-­-DT in development - VIIRS is similar, yet different then MODIS - With 50% wider swath, VIIRS has daily coverage - Ensures algorithm consistency with MODIS. - Currently: 20% NPP vs Aqua offset over ocean. - Only small bias (%) over land (2012-­-2016) - Can VIIRS/MODIS create aerosol CDR? Calibration for MODIS - VIIRS continues to fundamentally important. It's not just Terra, or just Aqua, or just NPP-­-VIIRS, I really want to push synergistic calibration.

  11. Telomeric repeat-containing RNA (TERRA) and telomerase are components of telomeres during mammalian gametogenesis.

    Science.gov (United States)

    Reig-Viader, Rita; Vila-Cejudo, Marta; Vitelli, Valerio; Buscà, Rafael; Sabaté, Montserrat; Giulotto, Elena; Caldés, Montserrat Garcia; Ruiz-Herrera, Aurora

    2014-05-01

    Telomeres are ribonucleoprotein structures at the end of chromosomes composed of telomeric DNA, specific-binding proteins, and noncoding RNA (TERRA). Despite their importance in preventing chromosome instability, little is known about the cross talk between these three elements during the formation of the germ line. Here, we provide evidence that both TERRA and the telomerase enzymatic subunit (TERT) are components of telomeres in mammalian germ cells. We found that TERRA colocalizes with telomeres during mammalian meiosis and that its expression progressively increases during spermatogenesis until the beginning of spermiogenesis. While both TERRA levels and distribution would be regulated in a gender-specific manner, telomere-TERT colocalization appears to be regulated based on species-specific characteristics of the telomeric structure. Moreover, we found that TERT localization at telomeres is maintained throughout spermatogenesis as a structural component without affecting telomere elongation. Our results represent the first evidence of colocalization between telomerase and telomeres during mammalian gametogenesis.

  12. Technology Demonstration Summary: Terra Vac In Situ Vacuum Extraction System, Groveland, Massachusetts

    Science.gov (United States)

    Terra Vac Inc's vacuum extraction system was demonstrated at the Valley Manufactured Products Company, Inc., site in Groveland, Massachusetts. The property is part of the Groveland Wells Superfund site and is contaminated mainly by trichloroethylene (TCE). Vacuum extraction...

  13. EASE-Grid Land Cover Classifications Derived from Boston University MODIS/Terra Land Cover Data

    Data.gov (United States)

    National Aeronautics and Space Administration — These data provide land cover classifications derived from the Boston University MOD12Q1 V004 MODIS/Terra 1 km Land Cover Product (Friedl et al. 2002). The data are...

  14. Development of Terra Harvest compliant plug-ins for McQ Unattended Ground Sensors (UGS)

    Science.gov (United States)

    Roeder, Brent W.; Fish, Robert C.

    2013-05-01

    The Army Research Lab (ARL), in collaboration with the Defense Intelligence Agency (DIA) and representatives from industry, recently validated the feasibility of the Terra Harvest architecture by successfully integrating dozens of Intelligence, Surveillance, and Reconnaissance (ISR) assets at the Trident Spectre 12 (TS12) exercise in Fort Story, VA. Based on the exercise, it is evident that Terra Harvest will greatly simplify the process of integrating disparate ISR systems. By reducing this complexity, Terra Harvest will increase the variety of devices U.S. soldiers have at their disposal giving them a greater technological advantage over their adversaries than ever before. This paper describes McQ's effort to develop Terra Harvest compliant plug-ins for its UGS along with lessons learned from their demonstration at TS12.

  15. Mars Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA’s Mars Exploration Program (MEP) calls for a series of highly ambitious missions over the next decade and beyond. The overall goals of the MEP must be...

  16. Mars' core and magnetism.

    Science.gov (United States)

    Stevenson, D J

    2001-07-12

    The detection of strongly magnetized ancient crust on Mars is one of the most surprising outcomes of recent Mars exploration, and provides important insight about the history and nature of the martian core. The iron-rich core probably formed during the hot accretion of Mars approximately 4.5 billion years ago and subsequently cooled at a rate dictated by the overlying mantle. A core dynamo operated much like Earth's current dynamo, but was probably limited in duration to several hundred million years. The early demise of the dynamo could have arisen through a change in the cooling rate of the mantle, or even a switch in convective style that led to mantle heating. Presently, Mars probably has a liquid, conductive outer core and might have a solid inner core like Earth.

  17. Internal constitution of Mars.

    Science.gov (United States)

    Anderson, D. L.

    1972-01-01

    Models of the internal structure of Mars consistent with the mass, radius and moment of inertia of the planet are constructed. The models assume that the radius of the core is between 0.36 and 0.60 of the radius of the planet, that the zero-pressure density of the mantle is between 3.54 and 3.49 g/cu cm, and that the planet contains 25 to 28% iron. Meteorite models of Mars containing 25 wt % iron and 12 wt % core are also proposed. It is maintained that Mars in contrast to the earth is an incompletely differentiated planet with a core substantially richer in sulfur than the core of the earth. The absence of a magnetic field on Mars is possibly linked with lack of lunar precessional torque and the small size and high resistivity of the Martian core.

  18. Mars Express & Co

    Science.gov (United States)

    Borgeest, Ulf; Staude, Jakob; Kratzenber-Annies, Volker; Coradini, Marcello; Flury, Walter; Jaumann, Ralf; Neukum, Gerhard; Ongaro, Franco; Lemke, Dietrich; Althaus, Tilmann; Fuhrmeister, Birgit

    Contents: Europa und der übrige Kosmos. Der Weltraum und das öffentliche Interesse an ihm. Europa besucht Mars. INTEGRAL - Blick ins Herz der Galaxis. ISO - Von der Idee zum Instrument. Dienstreisen ins All. ENVISAT.

  19. Mars Rover Photos API

    Data.gov (United States)

    National Aeronautics and Space Administration — This API is designed to collect image data gathered by NASA's Curiosity, Opportunity, and Spirit rovers on Mars and make it more easily available to other...

  20. Factors Influencing Consumer Behavior Towards Online Shopping in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Hani A

    2015-08-01

    Full Text Available This study intends to identify factors that may affect consumer behavior in Saudi Arabia while shopping online. Although Saudi Arabia has the largest and fastest growing ICT in the Middle East and the online shopping activities in Saudi are increasing rapidly, it is still lagging behind the global development. The four factors–website design quality, perceived trust, perceived convenience and advertisements & promotions were selected from the available literature. A survey was conducted and questionnaire that includes 25 questions was distributed randomly to a sample of 107 participants in Dammam city (in the Eastern Province of the kingdom. The collected data was analyzed by using SPSS software. The result indicates one hypothesis has been accepted. The findings of the study are analyzed and discussed further at the end of this paper.

  1. BURIAL AND EXHUMATION OF THE TERRA NOVA BAY REGION, TRANSANTARCTIC MOUNTAINS

    OpenAIRE

    Prenzel, Jannis

    2014-01-01

    This thesis focuses on the Terra Nova Bay region in the Ross Sea sector of the Transantarctic Mountains. For quantification of the burial and exhumation history, thermochronological methods were applied on samples from vertical profiles across the basement in the northern Terra Nova Bay region (Eisenhower Range, Deep Freeze Range) and supplemented by paleotemperature analysis on overlying Beacon sandstones from the Eisenhower Range and published thermochronological data of vertical basement p...

  2. Uji In Vitro Aktivitas Antelmintik Ekstrak Etanol Daun Pugun Tanoh [Curanga fel-terrae (Lour.) Merr.

    OpenAIRE

    Ginting, Grace Anastasia br

    2016-01-01

    Background: Ethanolic extract of Curanga fel-terrae (Lour.) Merr. leaves obtained by maceration has anthelmintic activity against Pheretima posthuma. However the anthelmintic activity is affected by extraction method. Soxhletation can extract more chemical compounds of plant than maceration. Objective: Aim of this study was to evaluate the in vitro anthelmintic activity of leaf ethanolic extract of C. fel-terrae obtained by soxhletation against P. posthuma. Methods: Dried material of C....

  3. Uji In vitro Aktivitas Antelmintik Ekstrak Etilasetat Daun Pugun Tanoh [Curanga fel-terrae (Lour.) Merr.

    OpenAIRE

    Sitepu, Maria Atrina

    2016-01-01

    Helminthiasis is a world health problem. Emerging of helminthical resistant strain to anthelmintics leads to the difficulty of helminthiasis treatment. Therefore, it is nessecary to do study to find out a new anthelmintic source. This study was to determine characteristics of dried material and ethylacetate extract of Curanga fel-terrae leaves, as well as the anthelmintic activity of the leaves extract. The extract was prepared by extracting C.fel-terrae dried leaves powder in ethylacetate...

  4. Mars Exploration Architecture

    Science.gov (United States)

    Jordan, James F.; Miller, Sylvia L.

    2000-01-01

    The architecture of NASA's program of robotic Mars exploration missions received an intense scrutiny during the summer months of 1998. We present here the results of that scrutiny, and describe a list of Mars exploration missions which are now being proposed by the nation's space agency. The heart of the new program architecture consists of missions which will return samples of Martian rocks and soil back to Earth for analysis. A primary scientific goal for these missions is to understand Mars as a possible abode of past or present life. The current level of sophistication for detecting markers of biological processes and fossil or extant life forms is much higher in Earth-based laboratories than possible with remotely deployed instrumentation, and will remain so for at least the next decade. Hence, bringing Martian samples back to Earth is considered the best way to search for the desired evidence. A Mars sample return mission takes approximately three years to complete. Transit from Earth to Mars requires almost a single year. After a lapse of time of almost a year at Mars, during which orbital and surface operations can take place, and the correct return launch energy constraints are met, a Mars-to-Earth return flight can be initiated. This return leg also takes approximately one year. Opportunities to launch these 3-year sample return missions occur about every 2 years. The figure depicts schedules for flights to and from Mars for Earth launches in 2003, 2005, 2007 and 2009. Transits for less than 180 deg flight angle, measured from the sun, and more than 180 deg are both shown.

  5. Giant saltation on Mars

    OpenAIRE

    Almeida, Murilo P.; Parteli, Eric J. R.; José S. Andrade; Herrmann, Hans J.

    2008-01-01

    Saltation, the motion of sand grains in a sequence of ballistic trajectories close to the ground, is a major factor for surface erosion, dune formation, and triggering of dust storms on Mars. Although this mode of sand transport has been matter of research for decades through both simulations and wind tunnel experiments under Earth and Mars conditions, it has not been possible to provide accurate measurements of particle trajectories in fully developed turbulent flow. Here we calculate the mo...

  6. Mars Observer mission

    OpenAIRE

    Albee, A. L.; Arvidson, R.E.; Palluconi, F. D.

    1992-01-01

    The Mars Observer mission will extend the exploration and characterization of Mars by providing new and systematic measurements of the atmosphere, surface, and interior of the planet. These measurements will be made from a low-altitude polar orbiter over a period of 1 Martian year, permitting repetitive observations of the surface and of the seasonal variations of the atmosphere. The mission will be conducted in a manner that will provide new and valuable scientific data using a distributed d...

  7. Automated inundation monitoring using TerraSAR-X multitemporal imagery

    Science.gov (United States)

    Gebhardt, S.; Huth, J.; Wehrmann, T.; Schettler, I.; Künzer, C.; Schmidt, M.; Dech, S.

    2009-04-01

    The Mekong Delta in Vietnam offers natural resources for several million inhabitants. However, a strong population increase, changing climatic conditions and regulatory measures at the upper reaches of the Mekong lead to severe changes in the Delta. Extreme flood events occur more frequently, drinking water availability is increasingly limited, soils show signs of salinization or acidification, species and complete habitats diminish. During the Monsoon season the river regularly overflows its banks in the lower Mekong area, usually with beneficial effects. However, extreme flood events occur more frequently causing extensive damage, on the average once every 6 to 10 years river flood levels exceed the critical beneficial level X-band SAR data are well suited for deriving inundated surface areas. The TerraSAR-X sensor with its different scanning modi allows for the derivation of spatial and temporal high resolved inundation masks. The paper presents an automated procedure for deriving inundated areas from TerraSAR-X Scansar and Stripmap image data. Within the framework of the German-Vietnamese WISDOM project, focussing the Mekong Delta region in Vietnam, images have been acquired covering the flood season from June 2008 to November 2008. Based on these images a time series of the so called watermask showing inundated areas have been derived. The product is required as intermediate to (i) calibrate 2d inundation model scenarios, (ii) estimate the extent of affected areas, and (iii) analyze the scope of prior crisis. The image processing approach is based on the assumption that water surfaces are forward scattering the radar signal resulting in low backscatter signals to the sensor. It uses multiple grey level thresholds and image morphological operations. The approach is robust in terms of automation, accuracy, robustness, and processing time. The resulting watermasks show the seasonal flooding pattern with inundations starting in July, having their peak at the end

  8. TerraFERMA: Harnessing Advanced Computational Libraries in Earth Science

    Science.gov (United States)

    Wilson, C. R.; Spiegelman, M.; van Keken, P.

    2012-12-01

    Many important problems in Earth sciences can be described by non-linear coupled systems of partial differential equations. These "multi-physics" problems include thermo-chemical convection in Earth and planetary interiors, interactions of fluids and magmas with the Earth's mantle and crust and coupled flow of water and ice. These problems are of interest to a large community of researchers but are complicated to model and understand. Much of this complexity stems from the nature of multi-physics where small changes in the coupling between variables or constitutive relations can lead to radical changes in behavior, which in turn affect critical computational choices such as discretizations, solvers and preconditioners. To make progress in understanding such coupled systems requires a computational framework where multi-physics problems can be described at a high-level while maintaining the flexibility to easily modify the solution algorithm. Fortunately, recent advances in computational science provide a basis for implementing such a framework. Here we present the Transparent Finite Element Rapid Model Assembler (TerraFERMA), which leverages several advanced open-source libraries for core functionality. FEniCS (fenicsproject.org) provides a high level language for describing the weak forms of coupled systems of equations, and an automatic code generator that produces finite element assembly code. PETSc (www.mcs.anl.gov/petsc) provides a wide range of scalable linear and non-linear solvers that can be composed into effective multi-physics preconditioners. SPuD (amcg.ese.ic.ac.uk/Spud) is an application neutral options system that provides both human and machine-readable interfaces based on a single xml schema. Our software integrates these libraries and provides the user with a framework for exploring multi-physics problems. A single options file fully describes the problem, including all equations, coefficients and solver options. Custom compiled applications are

  9. Mental health system in Saudi Arabia: an overview

    Directory of Open Access Journals (Sweden)

    Qureshi NA

    2013-08-01

    Full Text Available Naseem Akhtar Qureshi,1 Abdulhameed Abdullah Al-Habeeb,2 Harold G Koenig3 1General Administration for Research and Studies, 2Mental Health and Social Services, Ministry of Health, Riyadh, Saudi Arabia; 3Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA Background: There is evidence that mapping mental health systems (MHSs helps in planning and developing mental health care services for users, families, and other caregivers. The General Administration of Mental Health and Social Services of the Ministry of Health over the past 4 years has sought to streamline the delivery of mental health care services to health consumers in Saudi Arabia. Objective: We overview here the outcome of a survey that assessed the Saudi MHS and suggest strategic steps for its further improvement. Method: The World Health Organization Assessment Instrument for Mental Health Systems was used systematically to collect information on the Saudi MHS in 2009–2010, 4 years after a baseline assessment. Results: Several mental health care milestones, especially provision of inpatient mental health services supported by a ratified Mental Health Act, were achieved during this period. However, community mental health care services are needed to match international trends evident in developed countries. Similarly, a larger well-trained mental health workforce is needed at all levels to meet the ever-increasing demand of Saudi society. Conclusion: This updated MHS information, discussed in light of international data, will help guide further development of the MHS in Saudi Arabia in the future, and other countries in the Eastern Mediterranean region may also benefit from Saudi experience. Keywords: Saudi Arabia, mental health system, organization, legal issues, research, training

  10. Puberty Onset Among Boys in Riyadh, Saudi Arabia

    OpenAIRE

    Al Alwan, Ibrahim; Felimban, Naila; Altwaijri, Yasmin; Tamim, Hani; Al Mutair, Angham; Shoukri, Mohamed; Tamimi, Waleed

    2010-01-01

    Background: The ages of onset of pubertal characteristics are influenced by genetic, geographic, dietary and socioeconomic factors; however, due to lack of country-specific norms, clinicians in Saudi Arabia use Western estimates as standards of reference for local children. Aims: The aim of the Riyadh Puberty Study was to provide data on pubertal development to determine the average age of onset of pubertal characteristics among Saudi boys. Methods: Cross-sectional study among male school chi...

  11. Saudi Arabia; Staff Report for the 2014 Article IV Consultation

    OpenAIRE

    International Monetary Fund

    2014-01-01

    KEY ISSUES Context. Saudi Arabia’s economy has grown very strongly in recent years, benefitting from high oil prices and output, strong private sector activity, and government spending. It has played a systemic and stabilizing role in the global oil market. The economy has not been affected by the recent global financial market volatility. The Saudi population is young, growing, and increasingly well educated. Outlook and risks. The near term economic outlook is positive. Oil production is ...

  12. Pharmacy Education in Jordan, Saudi Arabia, and Kuwait

    OpenAIRE

    Al-Wazaify, Mayyada; Matowe, Lloyd; Albsoul-Younes, Abla; Al-Omran, Ola A.

    2006-01-01

    The practice of pharmacy, as well as pharmacy education, varies significantly throughout the world. In Jordan, Kuwait, and Saudi Arabia, the profession of pharmacy appears to be on the ascendance. This is demonstrated by an increase in the number of pharmacy schools and the number of pharmacy graduates from pharmacy programs. One of the reasons pharmacy is on the ascendance in these countries is government commitment to fund and support competitive, well-run pharmacy programs.

  13. Anthropometric predictors of dyslipidemia among adults in Saudi Arabia

    OpenAIRE

    Saeed, Abdalla A.

    2013-01-01

    Background: dyslipidemia and obesity are key independent modifiable risk factors for many non communicable chronic diseases. Patterns of association between these factors may help prevention and control. This study aims to assess the association between lipids profile and obesity among adults in Kingdom of Saudi Arabia and identify anthropometric predictors of dyslipidemia.Methods: data were collected and analyzed from a cross-sectional study using WHO STEPwise approach that included 4 990 Sa...

  14. The Impact of Urbanization on Energy Intensity in Saudi Arabia

    OpenAIRE

    Mounir Belloumi; Atef Saad Alshehry

    2016-01-01

    This paper investigates the long-term and causal relationship between energy intensity, real GDP per capita, urbanization and industrialization in Saudi Arabia over the period 1971–2012 using the breakpoint unit root tests developed by Perron (1989) and the autoregressive distributed lag (ARDL) model bounds testing to cointegration proposed by Pesaran et al. (2001) and employing a modified version of the Granger causality test proposed by Toda and Yamamoto (1995). Additionally, to test the ro...

  15. Leadership Role of School Superintendents in Saudi Arabia

    OpenAIRE

    Mohamed A. Almannie

    2015-01-01

    This study examines the practice of school superintendents in Saudi Arabia in five roles as seen by education supervisors within school district offices. The purpose of the study is to examine the leadership of school superintendents in these five roles: work environment, rules and regulations, implementation of technology, accountability, and professional development of the education supervisors in school districts. The study sample consists of 276 education supervisors working in 30 school ...

  16. Developmental oral anomalies among schoolchildren in Gizan region, Saudi Arabia.

    Science.gov (United States)

    Salem, G; Holm, S A; Fattah, R; Basset, S; Nasser, C

    1987-06-01

    The present report gives prevalence values for some developmental oral anomalies in 1932 schoolchildren aged 6-12 yr in Gizan region, Saudi Arabia. The developmental oral anomalies identified in this study were: torus palatinus (1.4%), fissured tongue (0.8%), geographic tongue (0.2%), and tongue tie (0.1%). None of the following developmental oral anomalies were observed: lip pits, cleft lip and/or palate, torus mandibularis, microglossia, macroglossia or median rhomboid glossitis. PMID:3474099

  17. Seroepidemiology of Asymptomatic Dengue Virus Infection in Jeddah, Saudi Arabia

    OpenAIRE

    Jamjoom, Ghazi A.; Azhar, Esam I.; Moujahid A. Kao; Radadi, Raja M.

    2016-01-01

    BACKGROUND Although virologically confirmed dengue fever has been recognized in Jeddah, Saudi Arabia, since 1994, causing yearly outbreaks, no proper seroepidemiologic studies on dengue virus have been conducted in this region. Such studies can define the extent of infection by this virus and estimate the proportion that may result in disease. The aim of this study was to measure the seroprevalence of past dengue virus infection in healthy Saudi nationals from different areas in the city of J...

  18. WATER IN THE KINGDOM OF SAUDI ARABIA: SUSTAINABLE MANAGEMENT OPTIONS

    OpenAIRE

    KKhodran H. Al-Zahrani and M. B. Baig

    2011-01-01

    Water is one of the most precious and valuable resources affecting the Saudi development plans. The acute shortage of fresh water resources poses a major challenge in Saudi Arabia. Demand for fresh water is on the rise as sufficient water is no longer available to meet daily needs. Some 95% of water comes from aquifers. Desalination plants and waste water reclamation projects provide about 4% and 1% water respectively. About 30% of the water for household consumption comes from desalinating p...

  19. Transition to knowledge-based economy in Saudi Arabia

    OpenAIRE

    Nour, S.

    2014-01-01

    This paper discusses the progress in transition to knowledge-based economy in Saudi Arabia. As for the methodology, this paper uses updated secondary data obtained from different sources. It uses both descriptive and comparative approaches and uses the OECD definition of knowledge-based economy and the World Bank Knowledge Index (KI) and Knowledge Economy Index (KEI) and other indicators often used in the international literature to examine progress in transition to a knowledge-based economy ...

  20. Trends in Ectopic Pregnancies in Eastern Saudi Arabia

    OpenAIRE

    Haifa Abdulaziz Al-Turki

    2013-01-01

    Background. The objective of this study was to estimate trends in ectopic pregnancies (EP) in a tertiary care center of Eastern Saudi Arabia. Method. Information about patients with ectopic pregnancies who had been admitted to King Fahd Hospital of the University, AlKhobar, between January 2000 and 31 December 2011 was collected from a computerized hospital registry. Age-specific ectopic pregnancy incidence was calculated. The data was analyzed using SPSS (Statistical Package for the Social S...

  1. Mars Rover RTG Study

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1989-11-27

    This report summarizes the results of a Radioisotope Thermoelectric Generator (RTG) design study conducted by Fairchild Space Company at the direction of the U.S. Department of Energy's Office of Special Applications, in support of the Mars Rover and Sample Return mission under investigation at NASA's Jet Propulsion Laboratory. Presented at the 40th Congress of the IAF, Oct. 7-13, 1989 in Torremolinos, Malaga-Spain. The paper describes the design and analysis of Radioisotope Thermoelectric Generators (RTGs) for powering the Mars Rover vehicle, which is a critical element of the unmanned Mars Rover and Sample Return mission (MRSR). The RTG design study was conducted by Fairchild Space for the U.S. DOE in support of the JPL MRSR Project. The paper briefly describes a reference mission scenario, an illustrative Rover design and activity pattern on Mars, and its power system requirements and environmental constraints, including the RTG cooling requirements during transit to Mars. It summarizes the baseline RTG's mass breakdown, and presents a detailed description of its thermal, thermoelectric, and electrical analysis. The results presented show the RTG performance achievable with current technology, and the performance improvements that would be achievable with various technology developments. It provides a basis for selecting the optimum strategy for meeting the Mars Rover design goals with minimal programmatic risk and cost. Cross Reference CID #7135 dated 10/1989. There is a duplicate copy. This document is not relevant to the OSTI Library. Do not send.

  2. Life on Mars

    Science.gov (United States)

    McKay, Christopher P.; Cuzzi, Jeffrey (Technical Monitor)

    1996-01-01

    Although the Viking results may indicate that Mars has no life today, the possibility exists that Mars may hold the best record of the events that led to the origin of life. There is direct geomorphological evidence that in the past Mars had large amounts of liquid water on its surface. Atmospheric models would suggest that this early period of hydrological activity was due to the presence of a thick atmosphere and the resulting warmer temperatures. From a biological perspective the existence of liquid water, by itself motivates the question of the origin of life on Mars. From studies of the Earth's earliest biosphere we know that by 3.5 Gyr. ago, life had originated on Earth and reached a fair degree of biological sophistication. Surface activity and erosion on Earth make it difficult to trace the history of life before the 3.5 Gyr timeframe. If Mars did maintain a clement environment for longer than it took for life to originate on Earth, then the question of the origin of life on Mars follows naturally.

  3. A three-state model for the regulation of telomerase by TERRA and hnRNPA1.

    Science.gov (United States)

    Redon, Sophie; Zemp, Ivo; Lingner, Joachim

    2013-10-01

    Telomeres, the physical ends of eukaryotic chromosomes, are transcribed into telomeric repeat-containing RNA (TERRA), a large non-coding RNA, which forms an integral part of telomeric heterochromatin. In vitro, naked TERRA molecules are efficient inhibitors of human telomerase, base-pairing via their 5'-UUAGGG-3' repeats with the template sequence of telomerase RNA, in addition to contacting the telomerase reverse transcriptase protein subunit. In vivo, however, TERRA-mediated inhibition of telomerase can be prevented by unknown mechanisms. Also, heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) has been implicated in telomere length control. In vivo, TERRA is partially associated with hnRNPA1, and hnRNPA1 is also detected at telomeres. We demonstrate that on binding of TERRA, hnRNPA1 can alleviate the TERRA-mediated inhibition of telomerase. However, when in excess over TERRA, hnRNPA1 becomes itself an inhibitor of telomere extension, on binding of the telomeric DNA substrate. Yet, hnRNPA1 has no notable direct effects on the telomerase catalysis. Our in vitro results suggest that TERRA-mediated telomerase inhibition may be prevented by hnRNPA1 in vivo. Telomere extension by telomerase may require balanced levels of TERRA and hnRNPA1 at telomeres. Thus, TERRA and hnRNPA1 can function as a bimolecular regulator to turn telomerase and the telomere on and off.

  4. Telomeric repeat-containing RNA TERRA: a noncoding RNA connecting telomere biology to genome integrity.

    Science.gov (United States)

    Cusanelli, Emilio; Chartrand, Pascal

    2015-01-01

    Telomeres are dynamic nucleoprotein structures that protect the ends of chromosomes from degradation and activation of DNA damage response. For this reason, telomeres are essential to genome integrity. Chromosome ends are enriched in heterochromatic marks and proper organization of telomeric chromatin is important to telomere stability. Despite their heterochromatic state, telomeres are transcribed giving rise to long noncoding RNAs (lncRNA) called TERRA (telomeric repeat-containing RNA). TERRA molecules play critical roles in telomere biology, including regulation of telomerase activity and heterochromatin formation at chromosome ends. Emerging evidence indicate that TERRA transcripts form DNA-RNA hybrids at chromosome ends which can promote homologous recombination among telomeres, delaying cellular senescence and sustaining genome instability. Intriguingly, TERRA RNA-telomeric DNA hybrids are involved in telomere length homeostasis of telomerase-negative cancer cells. Furthermore, TERRA transcripts play a role in the DNA damage response (DDR) triggered by dysfunctional telomeres. We discuss here recent developments on TERRA's role in telomere biology and genome integrity, and its implication in cancer.

  5. The Impact of Urbanization on Energy Intensity in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Mounir Belloumi

    2016-04-01

    Full Text Available This paper investigates the long-term and causal relationship between energy intensity, real GDP per capita, urbanization and industrialization in Saudi Arabia over the period 1971–2012 using the breakpoint unit root tests developed by Perron (1989 and the autoregressive distributed lag (ARDL model bounds testing to cointegration proposed by Pesaran et al. (2001 and employing a modified version of the Granger causality test proposed by Toda and Yamamoto (1995. Additionally, to test the robustness of the results, the fully modified ordinary least squares (OLS regression, the dynamic OLS regression, and the Hansen test are used. Our results show that the variables are cointegrated when energy intensity is the dependent variable. It is also found that urbanization positively affects energy intensity in both the short term and the long term. Causality tests indicate that urbanization causes economic output that causes energy intensity in the long term. Our results do not support the urban compaction hypothesis where urban cities benefit from basic public services and economies of scale for public infrastructure. Therefore, measures that slow down the rapid urbanization process should be taken to reduce energy intensity in Saudi Arabia. In addition, reducing energy inefficiency in energy consumption should be a strategy to attain sustainable development in the near future in Saudi Arabia.

  6. Magnetically inferred basement structure in central Saudi Arabia

    Science.gov (United States)

    Johnson, Peter R.; Stewart, Ian C. F.

    1995-05-01

    A compilation of magnetic data acquired during the past three decades for a region in central Saudi Arabia where Precambrian basement is partly exposed on the Arabian shield and partly concealed by overlying Phanerozoic strata, shows a central sector of conspicuous N-S-trending anomalies, a heterogeneous western sector of short-wavelength, high-intensity anomalies, and an eastern sector of low- to moderate-intensity broad-wavelength anomalies. Anomalies in the western and central sectors correlate with Neoproterozoic metavolcanic, metasedimentary, and intrusive rocks of the Arabian shield and are interpreted as delineating extensions of shield-type rocks down-dip beneath Phanerozoic cover. These rocks constitute terranes making up part of a Neoproterozoic orogenic belt that underlies Northeast Africa and western Arabia and it is proposed that their magnetically indicated easternmost extent marks the concealed eastern edge of the orogenic belt in central Arabia. The flat magnetic signature of the eastern sector, not entirely accounted for as an effect of deep burial, may reflect the presence of a crustal block different in character to the terranes of the orogenic belt and, speculatively, may outline a continental block that, according to some tectonic models of the region, collided with the Neoproterozoic terranes and thereby caused their deformation and tectonic accretion.

  7. A refined approach: Saudi Arabia moves beyond crude

    International Nuclear Information System (INIS)

    Saudi Arabia's role in global energy markets is changing. The kingdom is reshaping itself as a supplier of refined petroleum products while moving beyond its long-held role as a simple exporter of crude oil. This change is commensurate with the typical development trajectory of a state progressing to a more advanced stage of global economic integration. Gains from increased refining include reducing fuel imports and capturing margins now bequeathed to competitors. Refining also allows the kingdom to export its heavy crude oil to a wider array of customers, beyond select importers configured to handle heavy crudes. However, the move also presents strategic complications. The world's 'swing supplier' of oil may grow less willing or able to adjust supply to suit market demands. In the process, Saudi Arabia may have to update the old “oil for security” relationship that links it with Washington, augmenting it with a more diverse set of economic and investment ties with individual companies and countries, including China. -- Highlights: •Saudi Arabia is diverting crude oil into an expanding refining sector. •In doing so, the kingdom is moving beyond its role as global “swing supplier” of crude oil. •The kingdom will benefit from increased refining, including enhanced demand for heavy crude. •Strategic complications may force it to seek security partners beyond Washington

  8. Indoor Radon Concentration Levels in Najran Region, Saudi Arabia

    Science.gov (United States)

    Alyami, S. H.; Al-Ghamdi, S. S.; Baig, M. R.; Al-Garawi, M. S.

    2010-07-01

    Measurement of indoor radon concentration was performed in Najran region in the south west of Saudi Arabia, using CR-39 dosimeter. Despite many previous studies on indoor radon concentrations in Saudi Arabia, the data available are still limited. The objective of this study, which is the first of its kind in the region, is to have preliminary data of radon in this region. Such measurement will contribute towards further studies in this region of Saudi Arabia. The indoor radon concentration was measured in the villages of Fara Al-Jabal and Badr Al-Janoob (about 2000 m above sea level), Hadadah and Al-Khanig (about 1700 m above sea level). It was found that radon distribution in these villages is normal skewed to the right, with a range of 9±5 to 163±32 Bqm-3 and an average of 49±2 Bqm-3. It was also found that the average radon concentration is independent of altitude. Our findings show that the values are below the safe limit of 150 Bqm-3 set by the Environmental Protection Agency (EPA) of the USA

  9. Thromboembolism in inflammatory bowel diseases: a report from Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Hussain Issa

    2011-01-01

    Full Text Available Hussain Issa1, Sami Al-Momen1, Bahaa Bseiso1, Ghada Ali Al-Janobi1, Mohamad Al-Jama1, Fadel Ali Almousa1, Mahdi E Al-Jarodi1, Ahmed H Al-Salem21Department of Internal Medicine, King Fahad Specialist Hospital, Dammam, Saudi Arabia; 2Department of Pediatric Surgery, Maternity and Children Hospital, Dammam, Saudi ArabiaAbstract: Thromboembolism (TE is a serious but under-recognized complication of inflammatory bowel disease (IBD. This is specially so in developing countries where the incidence of IBD is low. In Saudi Arabia, IBD is considered to be rare, but the incidence is increasing. Where the clinical manifestations resemble those of developed countries, TE as a complication of IBD is considered to be very rare. This report describes six IBD patients with TE. This importance of the complication of TE is stressed, and physicians caring for these patients should be aware of it in order to obviate potential morbidity and mortality.Keywords: thromboembolism, inflammatory bowel disease, Crohn's disease, ulcerative colitis

  10. The MARS2013 Mars analog mission.

    Science.gov (United States)

    Groemer, Gernot; Soucek, Alexander; Frischauf, Norbert; Stumptner, Willibald; Ragonig, Christoph; Sams, Sebastian; Bartenstein, Thomas; Häuplik-Meusburger, Sandra; Petrova, Polina; Evetts, Simon; Sivenesan, Chan; Bothe, Claudia; Boyd, Andrea; Dinkelaker, Aline; Dissertori, Markus; Fasching, David; Fischer, Monika; Föger, Daniel; Foresta, Luca; Fritsch, Lukas; Fuchs, Harald; Gautsch, Christoph; Gerard, Stephan; Goetzloff, Linda; Gołebiowska, Izabella; Gorur, Paavan; Groemer, Gerhard; Groll, Petra; Haider, Christian; Haider, Olivia; Hauth, Eva; Hauth, Stefan; Hettrich, Sebastian; Jais, Wolfgang; Jones, Natalie; Taj-Eddine, Kamal; Karl, Alexander; Kauerhoff, Tilo; Khan, Muhammad Shadab; Kjeldsen, Andreas; Klauck, Jan; Losiak, Anna; Luger, Markus; Luger, Thomas; Luger, Ulrich; McArthur, Jane; Moser, Linda; Neuner, Julia; Orgel, Csilla; Ori, Gian Gabriele; Paternesi, Roberta; Peschier, Jarno; Pfeil, Isabella; Prock, Silvia; Radinger, Josef; Ramirez, Barbara; Ramo, Wissam; Rampey, Mike; Sams, Arnold; Sams, Elisabeth; Sandu, Oana; Sans, Alejandra; Sansone, Petra; Scheer, Daniela; Schildhammer, Daniel; Scornet, Quentin; Sejkora, Nina; Stadler, Andrea; Stummer, Florian; Taraba, Michael; Tlustos, Reinhard; Toferer, Ernst; Turetschek, Thomas; Winter, Egon; Zanella-Kux, Katja

    2014-05-01

    We report on the MARS2013 mission, a 4-week Mars analog field test in the northern Sahara. Nineteen experiments were conducted by a field crew in Morocco under simulated martian surface exploration conditions, supervised by a Mission Support Center in Innsbruck, Austria. A Remote Science Support team analyzed field data in near real time, providing planning input for the management of a complex system of field assets; two advanced space suit simulators, four robotic vehicles, an emergency shelter, and a stationary sensor platform in a realistic work flow were coordinated by a Flight Control Team. A dedicated flight planning group, external control centers for rover tele-operations, and a biomedical monitoring team supported the field operations. A 10 min satellite communication delay and other limitations pertinent to human planetary surface activities were introduced. The fields of research for the experiments were geology, human factors, astrobiology, robotics, tele-science, exploration, and operations research. This paper provides an overview of the geological context and environmental conditions of the test site and the mission architecture, in particular the communication infrastructure emulating the signal travel time between Earth and Mars. We report on the operational work flows and the experiments conducted, including a deployable shelter prototype for multiple-day extravehicular activities and contingency situations.

  11. Mars at Ls 357o

    Science.gov (United States)

    2006-01-01

    31 January 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 357o during a previous Mars year. This month, Mars looks similar, as Ls 357o occurred in mid-January 2006. The picture shows the south polar region of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn. Season: Northern Winter/Southern Summer

  12. Mars at Ls 324o

    Science.gov (United States)

    2005-01-01

    29 November 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 324o during a previous Mars year. This month, Mars looks similar, as Ls 324o occurred in mid-November 2005. The picture shows the south polar region of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn. Season: Northern Winter/Southern Summer

  13. Electronic crosstalk characterization of Terra MODIS long wave infrared channels

    Science.gov (United States)

    Madhavan, Sriharsha; Xiong, Xiaoxiong; Sun, Junqiang; Chiang, Kwofu; Wu, Aisheng

    2015-09-01

    Terra (T) MODerate-resolution Imaging Spectroradiometer (MODIS), a heritage Earth observing sensor has completed 15 years of operation as of December 18 2014. T-MODIS has 36 spectral channels designed to monitor the land, ocean, and atmosphere. The long term climate data record from T-MODIS is an important dataset for global change monitoring. Sixteen of the spectral channels fall in the Mid (M) (3.7-4.5μm) to Long (L) (6.7-14.1μm)Wave InfraRed (M/LWIR) wavelengths, which are also referred to as the Thermal Emissive Bands (TEBs). To date the TEBs have very satisfactory performance which is attributed to the scan-by-scan calibration using an on-board BlackBody whose temperature is traceable to the NIST temperature standards. However, with an aging instrument, it was observed from 2010 onwards that the Photo Voltaic LWIR channels (Bands 27-30) have suffered significantly from electronic crosstalk. This is mainly due to the deterioration of the electronic circuits of the relevant bands in the LWIR Focal Plane Array (FPA). In this paper, we report the characterization of the electronic crosstalk in the above-mentioned bands using the well characterized test site such as Dome Concordia (C). Such characterization can be used to reduce the effects of crosstalk when implemented in the future Level 1B reprocessing and thereby increasing the radiometric fidelity of the concerned bands.

  14. Estimating terra MODIS polarization effect using ocean data

    Science.gov (United States)

    Wald, Andrew; Brinkmann, Jake; Wu, Aisheng; Xiong, Jack

    2016-05-01

    Terra MODIS has been known since pre-launch to have polarization sensitivity, particularly in shortest-wavelength bands 8 and 9. On-orbit reflectance trending of pseudo-invariant sites show a variation in reflectance as a function of band and scan mirror angle of incidence consistent with time-dependent polarization effects from the rotating doublesided scan mirror. The MODIS Characterization Support Team [MCST] estimates the Mueller matrix trending from this variation as observed from a single desert site, but this effect is not included in Collection 6 [C6] calibration. Here we extend the MCST's current polarization sensitivity monitoring to two ocean sites distributed over latitude to help estimate the uncertainties in the derived Mueller matrix. The Mueller matrix elements derived for polarization-sensitive Band 8 for a given site are found to be fairly insensitive to surface brdf modeling. The site-to-site variation is a measure of the uncertainty in the Mueller estimation. Results for band 8 show that the polarization correction reduces mirror-side striping by up to 50% and reduces the instrument polarization effect on reflectance time series of an ocean target.

  15. Aoutomatic Oil Spill Detection Using TerraSAR-X Data

    Science.gov (United States)

    Zulipiye, Kaiyoumu; Balik Sanli, Fusun

    2016-07-01

    Oil release into the ocean may affect marine ecosystems and cause environmental pollution. Thus, oil spill detection and identification becomes critical important. Characterized by synoptic view over large regions, remote sensing has been proved to be a reliable tool for oil spill detection. Synthetic Aperture Radar (SAR) imagery shows returned signal that clearly distinguish oil from oil-free surface under optimal wind conditions, which makes it the most frequent used remote sensing technique in oil spill detection. Algorithms of automatic oil spill detection has already been developed for different SAR sensors, including RADARSAT and ENVISAT. In this study, we want to apply automatic oil spill detection algorithms on TerraSAR-X data which is previously developed for ASAR data. The applied methodology includes two steps as segmentation and classification. First segmentation algorithms compiled by C# have been applied under a Bayesian framework adopting a multi-level logistic. After segmentation different classification methods such as feature selection, filter, and embedded selection have been applied. As a result the used classifiers for oil spill detection will be compared, and the complete processing chain will be evaluated.

  16. Variations in effective compensation depth across Aphrodite Terra, Venus

    International Nuclear Information System (INIS)

    Aphrodite Terra is the largest elevated terrain on Venus and it serves as a focal point in current discussions of global tectonic style. Using the topography and gravity data acquired by the Pioneer Venus Orbiter (PVO) the authors have estimated an effective depth of Airy compensation for each of 75 orbital arcs that provide fairly uniform areal coverage of the entire province. The most pronounced pattern that emerges is a general increase in compensation depth to the east. The most rapid change occurs near 135 degree; the average west of there is 70 km, while the average to the east is 230 km. Superimposed on this larger trend are five distinctive regional patterns, four well defined peaks and one interval of widely scattered and poorly constrained depths. The maxima in compensation depth are well correlated with regional topographic highs. While these observations are easily reconciled with the general notion that Aphrodite is a region of crustal divergence, the great depth of compensation is difficult to accord with the more specific suggestion that Aphrodite is a terrestrial type divergent plate margin. The alternative suggestion that Aphrodite, and the other equatorial highlands on Venus, are surface manifestations of hot upwelling mantle plumes is consistent both with the great depths of compensation and with the pattern of regional peaks and intervening troughs. The broader scale increase in effective depth of compensation from west to east is more enigmatic, but it might reflect an age progression of the plumes

  17. High resolution geomagnetic field observations at Terra Nova bay, Antarctica

    Directory of Open Access Journals (Sweden)

    P. Palangio

    1996-06-01

    Full Text Available he preliminary results obtained from the analysis in the micropulsation frequency range of high time resolution magnetic field data recorded at the Antarctic Italian geomagnetic observatory at Terra Nova Bay for 11 consecutive days in February 1994 are reported. The spectral index over the whole Pcl-Pc5 frequency range is of the order of 3.5 and its value significantly increases beyond about 50 mHz. Spectral peaks in the Pc3 frequency range are common, especially during the daytime hours, and are probably due to the direct penetration of upstream waves in the cusp region. From the local time distribution of the micro pulsation power, a signifi - cant activity enhancement around the local magnetic noon emerges, in agreement with previous observations. The analysis of the signal polarisation characteristics in the horizontal plane shows a predominant CW polarisation in the Pcl-Pc3 frequency ranges with the major axis of the polarisation ellipse in the first quadrant.

  18. Stars come down to Earth As estrelas descem à Terra

    Directory of Open Access Journals (Sweden)

    Luiz Marcelo Brandão Carneiro

    2009-09-01

    Full Text Available Stars come down to Earth — A little known essay by Theodor W. Adorno, Stars Come Down to Earth is a study about horoscopes and superstition, written in the form of an analysis for the astrology column of the Los Angeles Times in the early 1950s. The German philosopher points out that the texts offered to the reader are an amalgam of the rational and the irrational, revealing the frankly ideological meanderings of their object. Obra não muito conhecida de Theodor W. Adorno, As estrelas descem à Terra é um estudo sobre horóscopo e superstição, originalmente dirigido à coluna de astrologia do Los Angeles Times do início dos anos 1950. O filósofo alemão, pontuando os textos oferecidos aos leitores como um mistura entre o racional e o irracional, revela os meandros do caráter francamente ideológico de seu objeto.

  19. Public awareness of blood donation in Central Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Abolfotouh MA

    2014-08-01

    Full Text Available Mostafa A Abolfotouh,1,2 Mohammed H Al-Assiri,1 Manar Al-Omani,2 Alwaleed Al Johar,3 Abdulaziz Al Hakbani,3 Ahmed S Alaskar1,2 1King Abdullah International Medical Research Center, 2King Saud bin-Abdulaziz University for Health Sciences, 3College of Medicine, King Saud University, Riyadh, Saudi Arabia Introduction: In Saudi Arabia, voluntary donors are the only source of blood donation. The aim of this study was to assess the level of public knowledge and attitude toward blood donation in Saudi Arabia. Methods: Using a previously validated questionnaire that comprises 38 questions to assess the levels of knowledge, attitudes, and motivations towards blood donation, 469 Saudi adults who attended different shopping malls in Riyadh, Saudi Arabia were surveyed. Multiple regression analyses were used to identify the significant predictors of blood donation, with the significance set at P<0.05. Results: Approximately half of all subjects (53.3% reported that they had previously donated blood, 39% of whom had donated more than once. The knowledge percentage mean score was 58.07%, denoting a poor level of knowledge, with only 11.9% reporting a good level of knowledge. The attitude percentage mean score towards donation was 75.45%, reflecting a neutral attitude towards donating blood, with 31.6% reporting a positive attitude. Donation was significantly more prevalent among males than females (66% versus 13.3%; P<0.001. After adjustment for confounders, a higher knowledge score (t=2.59; P=0.01, a higher attitude score (t=3.26; P=0.001, and male sex (t=10.45; P<0.001 were significant predictors of blood donation. An inability to reach the blood donation centers and a fear of anemia were the main reasons for females not donating blood (49.9% and 35.7%, respectively, whereas a lack of time was the main reason for males (59.5%. Conclusion: Prevalence of blood donation was less than satisfactory among the Saudi public, probably due to misconceptions, poor

  20. Bringing Terra Science to the People: 10 years of education and public outreach

    Science.gov (United States)

    Riebeek, H.; Chambers, L. H.; Yuen, K.; Herring, D.

    2009-12-01

    The default image on Apple's iPhone is a blue, white, green and tan globe: the Blue Marble. The iconic image was produced using Terra data as part of the mission's education and public outreach efforts. As far-reaching and innovative as Terra science has been over the past decade, Terra education and public outreach efforts have been equally successful. This talk will provide an overview of Terra's crosscutting education and public outreach projects, which have reached into educational facilities—classrooms, museums, and science centers, across the Internet, and into everyday life. The Earth Observatory web site was the first web site designed for the public that told the unified story of what we can learn about our planet from all space-based platforms. Initially conceived as part of Terra mission outreach in 1999, the web site has won five Webby awards, the highest recognition a web site can receive. The Visible Earth image gallery is a catalogue of NASA Earth imagery that receives more than one million page views per month. The NEO (NASA Earth Observations) web site and WMS (web mapping service) tool serves global data sets to museums and science centers across the world. Terra educational products, including the My NASA Data web service and the Students' Cloud Observations Online (S'COOL) project, bring Terra data into the classroom. Both projects target multiple grade levels, ranging from elementary school to graduate school. S'COOL uses student observations of clouds to help validate Terra data. Students and their parents have puzzled over weekly "Where on Earth" geography quizzes published on line. Perhaps the most difficult group to reach is the large segment of the public that does not seek out science information online or in a science museum or classroom. To reach these people, EarthSky produced a series of podcasts and radio broadcasts that brought Terra science to more than 30 million people in 2009. Terra imagery, including the Blue Marble, have

  1. Heavy Thunderstorm Synoptic Climatology and Forcing Mechanisms in Saudi Arabia.

    Science.gov (United States)

    Ghulam, Ayman S.

    2010-05-01

    Meteorologists are required to provide accurate and comprehensive weather information for planning and operational aviation, agricultural, water projects and also for the public. In general, weather phenomena such as thunderstorms over the area between the tropics and the middle latitudes are not fully understood, particularly in the Middle East area, for many reasons such as: 1) the complexity of the nature of the climate due to the wide-ranging diversity in the topography and landscape in the area; 2) the lack of meteorological data in the area; and 3) the lack of studies on local weather situations. In arid regions such as Saudi Arabia, the spatial and temporal variation of thunderstorms and associated rainfall are essential in determining their effects on social and economic conditions. Thunderstorms form rapidly, due to the fact that the significant heating of the air from the surface and the ensuing rainfall usually occurs within a short period of time. Thus, understanding thunderstorms and rainfall distribution in time and space would be useful for hydrologists, meteorologists and for environmental studies. Research all over the world has shown, however, that consideration of local factors like Low Level Jets (LLJ), moisture flux, sea breezes, and the Red Sea Convergence Zone (RSCZ) would be valuable in thunderstorm prediction. The combined effects of enhanced low-level moisture convergence and layer destabilization due to upslope flow over mountainous terrain has been shown to be responsible for thunderstorm development in otherwise non-favourable conditions. However, there might be other synoptic features associated with heavy thunderstorms or cause them, but these features have not been investigated in any research in Saudi Arabia. Thus, relating the local weather and synoptic situations with those over the middle latitudes will provide a valuable background for the forecasters to issue the medium-range forecasts which are important for many projects

  2. Mars Rover RTG Study

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1989-10-01

    Presented at the 40th Congress of the IAF, Oct. 7-13, 1989 in Torremolinos, Malaga-Spain. The paper describes the design and analysis of Radioisotope Thermoelectric Generators (RTGs) for powering the Mars Rover vehicle, which is a critical element of the unmanned Mars Rover and Sample Return mission (MRSR). The RTG design study was conducted by Fairchild Space for the U.S. DOE in support of the JPL MRSR Project. The paper briefly describes a reference mission scenario, an illustrative Rover design and activity pattern on Mars, and its power system requirements and environmental constraints, including the RTG cooling requirements during transit to Mars. It summarizes the baseline RTG's mass breakdown, and presents a detailed description of its thermal, thermoelectric, and electrical analysis. The results presented show the RTG performance achievable with current technology, and the performance improvements that would be achievable with various technology developments. It provides a basis for selecting the optimum strategy for meeting the Mars Rover design goals with minimal programmatic risk and cost. There is a duplicate copy and three copies in the file.

  3. The Mars Plasma Environment

    CERN Document Server

    Russell, C. T

    2007-01-01

    Mars sits very exposed to the solar wind and, because it is a small planet, has but a weak hold on its atmosphere. The solar wind therefore plays an important role in the evolution of the martian atmosphere. Over the last four decades a series of European missions, first from the Soviet Union and more recently from the European Space Agency, together with a single investigation from the U.S., the Mars Global Surveyor spacecraft, have added immeasurably to our understanding of the interplay between the solar wind and Mars atmosphere. Most recently the measurements of the plasma and fast neutral populations, conducted on the Mars Express spacecraft by the ASPERA-3 instrument have been acquired and analyzed. Their presentation to the public, most notably at the workshop "The Solar Wind Interaction and Atmosphere Evolution of Mars" held in Kiruna in early 2006, was the inspiration for this series of articles. However participation in the Kiruna conference was not a selection criterion for this volume. The papers ...

  4. CRISM's Global Mapping of Mars, Part 3

    Science.gov (United States)

    2007-01-01

    750, showing a part of Mars called Tyrrhena Terra in the ancient, heavily cratered highlands. The colored strips are CRISM multispectral survey data acquired over several months, in which each pixel began as calibrated 72-color spectrum of Mars. An experimental correction for illumination and atmospheric effects was applied to the data, to show how Mars' surface would appear if each strip was imaged with the same illumination and without an atmosphere. Then, the spectrum for each pixel was transformed into a set of 'summary parameters,' which indicate absorptions showing the presence of different minerals. Detections of the igneous, iron-bearing minerals olivine and pyroxene are shown in the red and blue image planes, respectively. Clay-like minerals called phyllosilicates, which formed when liquid water altered the igneous rocks, are shown in the green image plane. The gray areas between the strips are from an earlier mosaic of the planet taken by the Thermal Emission Imaging System (THEMIS) instrument on Mars Odyssey, and are included for context. Note that most areas imaged by CRISM contain pyroxene, and that olivine-containing rocks are concentrated on smooth deposits that fill some crater floors and the low areas between craters. Phyllosilicate-containing rocks are concentrated in and around small craters, such as the one at 13 degrees south latitude, 97 degrees east longitude. Their concentration in crater materials suggests that they were excavated when the craters formed, from a layer that was buried by the younger, less altered, olivine- and pyroxene-containing rocks. CRISM is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the

  5. Mycobacterium algericum sp. nov., a novel rapidly growing species related to M. terrae complex and associated with goat lung lesions

    OpenAIRE

    Sahraoui, N; Ballif, M.; Zelleg, S; Yousfi, N; C. Ritter; Friedel, U; Amstutz, B.; Yala, D; Boulahbal, F.; Guetarni, D; Zinsstag, J; Keller, P M

    2011-01-01

    A previously undescribed, rapid growing, non-chromogenic Mycobacterium novel species isolated from a goat lung lesion in Algeria is reported. Biochemical and molecular tools were used for its complete description and showed its affiliation to the M. terrae complex. 16S rRNA, rpoB and hsp65 sequences were unique. Phylogenetic analyses showed close relationship with M. terrae sensu stricto and M. senuense. Culture and biochemical characteristics were generally similar to M. terrae and M. senuen...

  6. Chromatin remodeling of human subtelomeres and TERRA promoters upon cellular senescence: commonalities and differences between chromosomes.

    Science.gov (United States)

    Thijssen, Peter E; Tobi, Elmar W; Balog, Judit; Schouten, Suzanne G; Kremer, Dennis; El Bouazzaoui, Fatiha; Henneman, Peter; Putter, Hein; Eline Slagboom, P; Heijmans, Bastiaan T; van der Maarel, Silvère M

    2013-05-01

    Subtelomeres are patchworks of evolutionary conserved sequence blocks and harbor the transcriptional start sites for telomere repeat containing RNAs (TERRA). Recent studies suggest that the interplay between telomeres and subtelomeric chromatin is required for maintaining telomere function. To further characterize chromatin remodeling of subtelomeres in relation to telomere shortening and cellular senescence, we systematically quantified histone modifications and DNA methylation at the subtelomeres of chromosomes 7q and 11q in primary human WI-38 fibroblasts. Upon senescence, both subtelomeres were characterized by a decrease in markers of constitutive heterochromatin, suggesting relative chromatin relaxation. However, we did not find increased levels of markers of euchromatin or derepression of the 7q VIPR2 gene. The repressed state of the subtelomeres was maintained upon senescence, which could be attributed to a rise in levels of facultative heterochromatin markers at both subtelomeres. While senescence-induced subtelomeric chromatin remodeling was similar for both chromosomes, chromatin remodeling at TERRA promoters displayed chromosome-specific patterns. At the 7q TERRA promoter, chromatin structure was co-regulated with the more proximal subtelomere. In contrast, the 11q TERRA promoter, which was previously shown to be bound by CCCTC-binding factor CTCF, displayed lower levels of markers of constitutive heterochromatin that did not change upon senescence, whereas levels of markers of facultative heterochromatin decreased upon senescence. In line with the chromatin state data, transcription of 11q TERRA but not 7q TERRA was detected. Our study provides a detailed description of human subtelomeric chromatin dynamics and shows distinct regulation of the TERRA promoters of 7q and 11q upon cellular senescence.

  7. Driving online shopping: Spending and behavioral differences among women in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Al-maghrabi, T.

    2010-01-01

    Full Text Available This study proposes a revised technology acceptance model that integrates expectation confirmation theory to measure gender differences with regard to continuance online shopping intentions in Saudi Arabia. The sample consists of 650 female respondents. A structural equation model confirms model fit. Perceived enjoyment, usefulness, and subjective norms are determinants of online shopping continuance in Saudi Arabia. High and low online spenders among women in Saudi Arabia are equivalent. The structural weights are also largely equivalent, but the regression paths from perceived site quality to perceived usefulness is not invariant between high and low e-shoppers in Saudi Arabia. This research moves beyond online shopping intentions and includes factors affecting online shopping continuance. The research model explains 60% of the female respondents’ intention to continue shopping online. Online strategies cannot ignore either the direct and indirect spending differences on continuance intentions, and the model can be generalized across Saudi Arabia.

  8. The Role and Responsibility of the National Regulator of Radiation Sources and Materials in Saudi Arabia

    International Nuclear Information System (INIS)

    There are neither nuclear power reactors nor are there research reactors in Saudi Arabia. However, the country imports a lot of radioactive sources that are used in different fields such as medicine, hydrology, industry and research. Usage of radioactive material is governed by national and the IAEA regulations for the safe usage and transport of radioactive materials. KACST (King Abdulaziz City for Science and Technology) is an independent scientific organization established in 1977. It is the national competent authority that sets the rules of transporting, using and disposing of radioactive sources in Saudi Arabia.. This paper discusses the role of KACST and other authorities in the country regarding the 1) licensing and evaluation of the importing and exporting applications of radioactive sources and/or devices in Saudi Arabia, 2) The regulatory framework of radiation protection in Saudi Arabia, 3) the management of radioactive wastes in Saudi Arabia. (author)

  9. Produtores familiares e estratégias ligadas à terra

    Directory of Open Access Journals (Sweden)

    Antonio Lázaro Sant'Ana

    2004-12-01

    Full Text Available A manutenção e/ou a ampliação da terra compõem o eixo central em torno do qual os produtores familiares organizam sua vida e seu trabalho. Este artigo analisa as estratégias desses produtores em relação à divisão de herança e à sucessão, e as formas que utilizam para aquisição de novas áreas. O levantamento das características das famílias e da propriedade foi realizado por meio de um questionário aplicado junto a 89 produtores familiares de três municípios da mesorregião de São José do Rio Preto (SP. Posteriormente foi entrevistado um terço dos produtores de cada município que havia respondido ao questionário. A análise das estratégias fundiárias mostrou uma grande diversidade na forma de partilhar a herança e de conduzir a sucessão, sendo que ambos os processos são apoiados, basicamente, em regras tradicionais, embora mantenham uma fachada de adequação às normas legais. Quanto às estratégias de aquisição de mais terras, observou-se que os produtores são capazes de organizar complexas formas de capitalização, centradas em maiores esforços no trabalho e na contenção de gastos, além da utilização de políticas públicas favoráveis e de práticas costumeiras. Os arranjos intra-familiares e as formas de cooperação ligadas ao parentesco mais amplo também se mostraram importantes para a ampliação da propriedade.The maintenance and/or expansion of land form the central axle along which family farming organize their livelihood and work.. This paper analyzes these producers' strategies that are related to division of inheritance and succession, and the forms of acquisition of new areas. The survey on the characteristics of families and property was carried out by a questionnaire in 89 familiar producers of three cities of São José do Rio Preto (SP region. Next, one third of those answering the questionnaire were interviewed in the same cities. The analysis of agrarian strategies showed a great

  10. Mars Aqueous Processing System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Aqueous Processing System (MAPS) is a novel technology for recovering oxygen, iron, and other constituents from lunar and Mars soils. The closed-loop...

  11. MOPITT Mechanisms 16 Years In-Orbit Operation on TERRA

    Science.gov (United States)

    Gibson, Andrew S.; Nichitiu, Florian; Caldwell, Dwight

    2016-01-01

    The 16th anniversary of the launch of NASA's Terra Spacecraft was marked on December 18, 2015, with the Measurements of Pollution in the Troposphere (MOPITT) instrument being a successful contributor to the NASA EOS flagship. MOPITT has been enabled by a large suite of mechanisms, allowing the instrument to perform long-duration monitoring of atmospheric carbon monoxide, providing global measurements of this important greenhouse gas for 16 years. Mechanisms have been successfully employed for scanning, cooling of detectors, and to optically modulate the gas path length within the instrument by means of pressure and gas cell length variation. The instrument utilizes these devices to perform correlation spectroscopy, enabling measurements with vertical resolution from the nadir view, and has thereby furthered understanding of source and global transport effects of carbon monoxide. Given the design requirement for a 5.25-year lifetime, the stability and performance of the majority of mechanisms have far surpassed design goals. With 16 continuously operating mechanisms in service on MOPITT, including 12 rotating mechanisms and 4 with linear drive elements, the instrument was an ambitious undertaking. The long life requirements combined with demands for cleanliness and optical stability made for difficult design choices including that of the selection of new lubrication processes. Observations and lessons learned with regards to many aspects of the mechanisms and associated monitoring devices are discussed here. Mechanism behaviors are described, including anomalies, long-term drive current/power, fill pressure, vibration and cold-tip temperature trends. The effectiveness of particular lubrication formulations and the screening method implemented is discussed in relation to continuous rotating mechanisms and stepper motors, which have exceeded 15 billon rotations and 2.5 billion steps respectively. Aspects of gas cell hermeticity, optical cleanliness, heater problems

  12. Parafilimonas terrae gen. nov., sp. nov., isolated from greenhouse soil.

    Science.gov (United States)

    Kim, Soo-Jin; Park, Joo-Hyeon; Lim, Jun-Muk; Ahn, Jae-Hyung; Anandham, Rangasamy; Weon, Hang-Yeon; Kwon, Soon-Wo

    2014-09-01

    A Gram-stain-negative, short rod-shaped, non-flagellated, yellow bacterium, designated strain 5GHs7-2(T), was isolated from a greenhouse soil sample in South Korea. 16S rRNA gene sequence analysis of strain 5GHs7-2(T) indicated that the isolate belonged to the family Chitinophagaceae, and exhibited the highest sequence similarities with members of the genera Terrimonas (89.2-92.6 %), Sediminibacterium (90.8-91.4 %) and Chitinophaga (89.2-91.7 %), Filimonas lacunae YT21(T) (91.7 %), members of the genus Segetibacter (90.2-91.6 %), Parasegetibacter luojiensis RHYL-37(T) (90.9 %) and Flavihumibacter petaseus T41(T) (91.2 %). Flexirubin-type pigments were present. The major cellular fatty acids of the novel strain were iso-C15 : 0, iso-C17 : 0 3-OH and iso-C15 : 1 G. The polar lipid profile consisted of a large amount of phosphatidylethanolamine, and moderate and small amounts of several unknown aminolipids and lipids. The only respiratory quinone of strain 5GHs7-2(T) was MK-7, and the DNA G+C content was 47.6 mol%. On the basis of the evidence presented, it is concluded that strain 5GHs7-2(T) represents a novel species of a new genus in the family Chitinophagaceae, for which the name Parafilimonas terrae gen. nov., sp. nov. is proposed. The type strain of the type species is 5GHs7-2(T) ( = KACC 17343(T) = DSM 28286(T)). PMID:24925599

  13. Deslizamentos de Terra e as Leis de Newton

    Directory of Open Access Journals (Sweden)

    Gleide Alencar do Nascimento Dias

    2013-07-01

    Full Text Available A física teórica e experimental pode ser relacionada ao nosso quotidiano, buscando desta forma o desenvolvimento científico para educadores e funcionar como um facilitador no aprendizado para os alunos. Procurou-se mostrar a interdisciplinaridade para o aluno, adaptando um antigo experimento da área de física através dos princípios das leis de Newton do movimento de um bloco em uma rampa inclinada com as forças que contribuem para os deslizamentos de terras em taludes, como também a influência da variação granulométrica. Os taludes ou encostas naturais são definidos como superfícies de maciços rochosos, terrosos ou mistos (solo e rocha. Na análise da estabilidade de taludes o método analítico é empregado no equilíbrio-limite no qual se utiliza um coeficiente ou Fator de Segurança (FS, onde são calculados pelo quociente entre a resistência do terreno e as forças motoras ao longo da superfície de movimentação. Observou-se que para uma rocha de superfície lisa em uma rampa com grãos na fração de areia a silte desliza a partir de um ângulo mais raso do que para superfície com grãos na fração de cascalho fino, onde as rochas deslizam em ângulos diferentes em diferentes tipos de grãos.

  14. Remanent magnetism at Mars

    Science.gov (United States)

    Curtis, S. A.; Ness, N. F.

    1988-01-01

    It is shown that a strong case can be made for an intrinsic magnetic field of dynamo origin for Mars earlier in its history. The typical equatorial magnetic field intensity would have been equal to about 0.01-0.1 gauss. The earlier dynamo activity is no longer extant, but a significant remanent magnetic field may exist. A highly non-dipole magnetic field could result from the remanent magnetization of the surface. Remanent magnetization may thus play an important role in the Mars solar wind interactions, in contrast to Venus with its surface temperatures above the Curie point. The anomalous characteristics of Mars'solar wind interaction compared to that of Venus may be explicable on this basis.

  15. Portugal é o mar

    OpenAIRE

    Meneses, Avelino de Freitas de

    2007-01-01

    Os oceanos são críticos para a sobrevivência e o bem-estar da Humanidade, pelo que as oportunidades que encerram estão ao alcance e são um desafio para todos nós. Longe vão os tempos em que o mar separava os países e os povos – hoje é o mar que os aproxima e lhes confere poder e competitividade. Sendo um facto que sempre que Portugal se voltou para o mar prosperou, é objetivo do presente trabalho conhecer as razões que contribuíram para que o país chegasse à atual situação. ...

  16. Magnetic storms on Mars

    DEFF Research Database (Denmark)

    Vennerstrøm, Susanne

    2011-01-01

    Based on data from the Mars Global Surveyor magnetometer we examine periods of significantly enhanced magnetic disturbances in the martian space environment. Using almost seven years of observations during the maximum and early declining phase of the previous solar cycle the occurrence pattern...... and typical time profile of such periods is investigated and compared to solar wind measurements at Earth. Typical durations of the events are 20–40h, and there is a tendency for large events to last longer, but a large spread in duration and intensity are found. The large and medium intensity events at Mars...... field disturbance at Mars is solar wind dynamic pressure variations associated with the eccentricity of the martian orbit around the Sun....

  17. Mars Observer's Global Mapping Mission

    OpenAIRE

    Albee, A. L.; Palluconi, D. F.

    1990-01-01

    The Mars Observer mission, scheduled for launch in September 1992, will provide an orbital platform at Mars from which the entire Martian surface and atmosphere will be observed beginning in late 1993. Mars Observer will extend the exploration and characterization of Mars by providing new and systematic measurements of the surface and atmosphere of the planet. These measurements will be made from a low-altitude polar orbiter over a period of one Martian year (687 Earth days), permitting repet...

  18. EquiMar

    DEFF Research Database (Denmark)

    Johnstone, C. M.; McCombes, T.; Bahaj, A. S.;

    2011-01-01

    / financiers etc when attempting to quantify the performance of a device since it makes it very difficult to reference and benchmark the performance of a marine energy converter. The EC Framework Programme VII EquiMar project has set out to develop a suite of Best Practices to be adopted when undertaking the...... performance evaluation of such systems in order to address this deficiency. This paper reports the development of a set of ‘Best Practices’ within the ECFPVII EquiMar project to be adopted for the performance quantification of wave and tidal energy converters as they evolve from an engineering concept to...

  19. Flying To Mars

    Institute of Scientific and Technical Information of China (English)

    周铭杨

    2015-01-01

    <正>Do you know"Mars migration programme"by SpaceX?It’s an immigrant plan to a planet—Mars,Sounds incredible,isn’t it?After two-round tests,Li Dapeng,graduating from Handan NO.1 high school in 2001,was selected.There entered four Chinese in final test.To be more precise,Li is the only one who comes from the mainland of China.Last weekend,Li came to our school for a speech.Driven by

  20. Mars sample return - Science

    Science.gov (United States)

    Blanchard, Douglas P.

    1988-01-01

    The possible scientific goals of a Mars sample return mission are reviewed, including the value of samples and the selection of sampling sites. The fundamental questions about Mars which could be studied using samples are examined, including planetary formation, differentiation, volcanism and petrogenesis, weathering, and erosion. Scenarios are presented for sample acquisition and analysis. Possible sampling methods and tools are discussed, including drilling techniques, types of rovers, and processing instruments. In addition, the possibility of aerocapture out of elliptical or circular orbit is considered.

  1. Lakes on Mars

    CERN Document Server

    Cabrol, Nathalie A

    2014-01-01

    On Earth, lakes provide favorable environments for the development of life and its preservation as fossils. They are extremely sensitive to climate fluctuations and to conditions within their watersheds. As such, lakes are unique markers of the impact of environmental changes. Past and current missions have now demonstrated that water once flowed at the surface of Mars early in its history. Evidence of ancient ponding has been uncovered at scales ranging from a few kilometers to possibly that of the Arctic ocean. Whether life existed on Mars is still unknown; upcoming missions may find critic

  2. The stratigraphy of Mars

    Science.gov (United States)

    Tanaka, Kenneth L.

    1986-01-01

    A global stratigraphy of Mars was developed from a global geologic map series derived from Viking images; the stratigraphy is composed of three maps. A new chronostratigraphic classification system which consists of lower, middle, and upper Noachian, Hesperian, and Amazonian systems is described. The crater-density boundaries of the chronostratigraphic units and the absolute ages of the Martian epochs aer estimated. The relative ages of major geologic units and featues are calculated and analyzed. The geologic history of Mars is summarized on the maps in terms of epochs.

  3. Toxicity assessment in marine sediment for the Terra Nova environmental effects monitoring program (1997-2010)

    Science.gov (United States)

    Whiteway, Sandra A.; Paine, Michael D.; Wells, Trudy A.; DeBlois, Elisabeth M.; Kilgour, Bruce W.; Tracy, Ellen; Crowley, Roger D.; Williams, Urban P.; Janes, G. Gregory

    2014-12-01

    This paper discusses toxicity test results on sediments from the Terra Nova offshore oil development. The Terra Nova Field is located on the Grand Banks approximately 350 km southeast of Newfoundland (Canada). The amphipod (Rhepoxynius abronius) survival and solid phase luminescent bacteria (Vibrio fischeri, or Microtox) assays were conducted on sediment samples collected from approximately 50 stations per program year around Terra Nova during baseline (1997), prior to drilling, and in 2000, 2001, 2002, 2004, 2006, 2008 and 2010 after drilling began. The frequency of toxic responses in the amphipod toxicity test was low. Of the ten stations that were toxic in environmental effects monitoring (EEM) years, only one (station 30(FE)) was toxic in more than one year and could be directly attributed to Terra Nova project activities. In contrast, 65 (18%) of 364 EEM samples were toxic to Microtox. Microtox toxicity in EEM years was not related to distance from Terra Nova drill centres or concentrations of >C10-C21 hydrocarbons or barium, the primary constituents of the synthetic-based drill muds used at Terra Nova. Of the variables tested, fines and strontium levels showed the strongest (positive) correlations with toxicity. Neither fines nor strontium levels were affected by drill cuttings discharge at Terra Nova, except at station 30(FE) (and that station was not toxic to Microtox). Benthic macro-invertebrate abundance, richness and diversity were greater in toxic than in non-toxic sediments. Therefore, Microtox responses indicating toxicity were associated with positive biological responses in the field. This result may have been an indirect function of the increased abundance of most invertebrate taxa in less sandy sediments with higher gravel content, where fines and strontium levels and, consequently, toxicity to Microtox were high; or chemical substances released by biodegradation of organic matter, where invertebrates are abundant, may be toxic to Microtox. Given

  4. A potential Mars 2020 rover landing site at a delta in Magong Crater, Mars

    Science.gov (United States)

    Hauber, E.; Platz, T.; Le Deit, L.; van Gasselt, S.; Kinch, K.; Madsen, M. B.; Rosenberg, H.

    2015-10-01

    For the upcoming NASA 2020 Mars rover mission we identified a potential landing site that meets all geological criteria including the presence of Noachian/Early Hesperian aqueous sediments and mineral phases and access to unaltered igneous rocks. Our proposed landing site is located at the terminus of Sabrina Vallis in Magong crater. The 25 km×20 km landing ellipse is centred at 11.990°N, 313.425°E. This site features deltaic sediments and distal lacustrine sediments. Weak signatures of Fe/Mg-bearing phyllosilicates were detected at central delta cliff sections. Lacustrine sediments are cut by a partially exhumed igneous dyke. On the crater floor of Magong crater remnants of an approximately 1m thick dark deposit are observed, which is interpreted to be a tephra layer sourced from an adjacent volcanic field within Lederberg crater. Detailed terra in analysis of the landing site shows that engineering constraints are met with respect to slope and relief.

  5. Vulkanisme en water op Mars?

    NARCIS (Netherlands)

    Van Loef, J.; Schmets, A.J.M.

    2005-01-01

    In januari 2004 werd Mars bezocht door de tweeling robotverkenners Spirit en Opportunity. Zij werden erop uitgestuurd om eindelijk het definitieve antwoord te geven op de vraag of er leven op Mars is geweest. Alles wijst er inmiddels op dat er op Mars ooit vloeibaar water stroomde. Of daarmee een be

  6. TERRA-Reinforced Association of LSD1 with MRE11 Promotes Processing of Uncapped Telomeres

    Directory of Open Access Journals (Sweden)

    Antonio Porro

    2014-02-01

    Full Text Available Telomeres protect chromosome ends from being recognized as sites of DNA damage. Upon telomere shortening or telomere uncapping induced by loss of telomeric repeat-binding factor 2 (TRF2, telomeres elicit a DNA-damage response leading to cellular senescence. Here, we show that following TRF2 depletion, the levels of the long noncoding RNA TERRA increase and LSD1, which binds TERRA, is recruited to telomeres. At uncapped telomeres, LSD1 associates with MRE11, one of the nucleases implicated in the processing of 3′ telomeric G overhangs, and we show that LSD1 is required for efficient removal of these structures. The LSD1-MRE11 interaction is reinforced in vivo following TERRA upregulation in TRF2-deficient cells and in vitro by TERRA-mimicking RNA oligonucleotides. Furthermore, LSD1 enhances the nuclease activity of MRE11 in vitro. Our data indicate that recruitment of LSD1 to deprotected telomeres requires MRE11 and is promoted by TERRA. LSD1 stimulates MRE11 catalytic activity and nucleolytic processing of uncapped telomeres.

  7. Peeling skin syndrome: 11 cases from Saudi Arabia

    International Nuclear Information System (INIS)

    Peeling skin syndrome (PSS) is a rare genodermatoses of probable autosomal recessive inheritance in Saudi Arabia, consanguinity of parents is common and consequently the occurrence of family disease, including that of the skin, is not uncommon. To characterize the clinical and pathological features of PSS in Saudi Arabia, we reviewed the medical records and clinical photographs of patients with recurring blistering diseases and conducted a histopathologic evaluation of skin biopsies to identify the site of cleavage. Eleven persons with PSS were seen at King Khalid National Guard Hospital in Jeddah between the years 1986 and 2005. Ages ranged between 2 and 15 years and there were 9 males (81.8%) and 2 females (18.2%). The most common presentation in the majority of patients was localized spontaneous peeling of the skin. Eight patients (72.8%) had a history of vesicles that were small, dry and peeled away. Trauma did no play role in blister formation. All patients were local from Bedouin tribes where a family history of a similar complaint was documented in 8 cases (72.7%). And consanguinity of marriage was evident on 6 patients (54.5%). Histological examination of the biopsies showed either intracorneal or superficial subcorneal cleavage above the granuler layer in all biopsied patients. Although rare, PSS occurs in Saudi Arabia and is most likely related to consanguinity of marriages. This disease is generally mild and is characterized by intrascorneal cleavage within the superficial epidermis. The disease should be recognized and not confused with other vasicobullous disease. (author)

  8. Aborting a malformed fetus: a debatable issue in saudi arabia.

    Science.gov (United States)

    Al-Alaiyan, Saleh; Alfaleh, Khalid M

    2012-01-01

    Congenital anomalies contribute a significant proportion of infant morbidity and mortality, as well as fetal mortality. They are generally grouped into three major categories: structural/metabolic, congenital infections, and other conditions. The most prevalent conditions include congenital heart defects, orofacial clefts, Down syndrome, and neural tube defects. Several prenatal diagnostic procedures have been introduced, both cytogenetic (such as chorion biopsy, amniocentesis and funiculocentesis) and biophysical (ultrasound 2-D, 3-D and 4-D, ultrasonography with Doppler, etc.). Insufficient data are currently available from Saudi Arabia on the epidemiology of the lethal congenital abnormalities which should be a priority due to high rate of consanguineous marriages among first cousins and their association with congenital anomalies. In terms of consanguinity and birth defects, a significant positive association has been consistently demonstrated between consanguinity and morbidity, and congenital defects with a complex etiology appear to be both more prevalent in consanguineous families and have a greater likelihood of recurrence. A debate regarding aborting a malformed fetus still exists among the senior Islamic scholars in many of the Islamic countries. The progressive interpretations of Islam have resulted in laws allowing for early abortion on request in two countries; six others permit abortion on health grounds and three more also allow abortion in cases of rape or fetal impairment. In Saudi Arabia, efforts to legalize abortion in certain circumstances have been recently discussed among Senior Religious Scholars and specialized physicians to permit abortions in certain circumstances. In this mini-review we discuss the current debate regarding aborting a malformed fetus in Saudi Arabia with a focus on the Islamic perspective. PMID:24027674

  9. Spatial Autocorrelation of Cancer Incidence in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Khalid Al-Ahmadi

    2013-12-01

    Full Text Available Little is known about the geographic distribution of common cancers in Saudi Arabia. We explored the spatial incidence patterns of common cancers in Saudi Arabia using spatial autocorrelation analyses, employing the global Moran’s I and Anselin’s local Moran’s I statistics to detect nonrandom incidence patterns. Global ordinary least squares (OLS regression and local geographically-weighted regression (GWR were applied to examine the spatial correlation of cancer incidences at the city level. Population-based records of cancers diagnosed between 1998 and 2004 were used. Male lung cancer and female breast cancer exhibited positive statistically significant global Moran’s I index values, indicating a tendency toward clustering. The Anselin’s local Moran’s I analyses revealed small significant clusters of lung cancer, prostate cancer and Hodgkin’s disease among males in the Eastern region and significant clusters of thyroid cancers in females in the Eastern and Riyadh regions. Additionally, both regression methods found significant associations among various cancers. For example, OLS and GWR revealed significant spatial associations among NHL, leukemia and Hodgkin’s disease (r² = 0.49–0.67 using OLS and r² = 0.52–0.68 using GWR and between breast and prostate cancer (r² = 0.53 OLS and 0.57 GWR in Saudi Arabian cities. These findings may help to generate etiologic hypotheses of cancer causation and identify spatial anomalies in cancer incidence in Saudi Arabia. Our findings should stimulate further research on the possible causes underlying these clusters and associations.

  10. Assessment of Ambient Air Quality in Riyadh City, Saudi Arabia.

    OpenAIRE

    B. H. Alharbi; M. J. Pasha; N. Tapper

    2014-01-01

    Concentrations of airborne particulate matter with an aerodynamic diameter less than 10 µm (PM10) and five gaseous air pollutants (O3, CO, NO2, SO2 and H2S) were measured over a period of approximately six years (October 1999-June 2004) at five air quality monitoring network stations of King Abulaziz City for Science and Technology (KACST) in Riyadh city, Saudi Arabia. The main objective of this study is to evaluate the quality of ambient air in relation to its possible effects on human healt...

  11. Strategic directions for university hospitals in Saudi Arabia.

    Science.gov (United States)

    Bin Abdulrahman, Khalid A; Tawfik, Bassel

    2016-01-01

    The kingdom of Saudi Arabia is currently witnessing a massive support for its healthcare services. This year's fiscal budget for health care is by far the largest in the history of the kingdom. While pursuing the conventional goals of healthcare delivery systems, such as equity, affordability and availability of services, the ministry of education (MOE), formerly called ministry of higher education (MOHE), is also seeking to achieve certain excellence standards, which are expected to set the bar for other countries in the region to follow suit. Almost all, under construction, university hospitals were adopting a paradigm shift in the standard of health care and training provided. This report summarizes these standards.

  12. Fruit and vegetable consumption among adults in Saudi Arabia, 2013

    Directory of Open Access Journals (Sweden)

    El Bcheraoui C

    2015-02-01

    Full Text Available Charbel El Bcheraoui,1 Mohammed Basulaiman,2 Mohammad A AlMazroa,2 Marwa Tuffaha,1 Farah Daoud,1 Shelley Wilson,1 Mohammad Y Al Saeedi,2 Faisal M Alanazi,2 Mohamed E Ibrahim,2 Elawad M Ahmed,2 Syed A Hussain,2 Riad M Salloum,2 Omer Abid,2 Mishal F Al-Dossary,2 Ziad A Memish,2 Abdullah A Al Rabeeah,2 Ali H Mokdad1 1Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA; 2Ministry of Health of the Kingdom of Saudi Arabia, Riyadh, Saudi Arabia Background: Dietary risks were the leading risk factors for death worldwide in 2010. However, current national estimates on fruit and vegetable consumption in the Kingdom of Saudi Arabia (KSA are nonexistent. We conducted a large household survey to inform the Saudi Ministry of Health (MOH on a major modifiable risk factor: daily consumption of fruits and vegetables. Methods: The Saudi Health Interview Survey is a national multistage survey of individuals aged 15 years or older. It includes questions on sociodemographic characteristics, tobacco consumption, diet, physical activity, health care utilization, different health-related behaviors, and self-reported chronic conditions. We used a backward elimination multivariate logistic regression model to measure association between the Centers for Disease Control and Prevention (CDC-recommended daily consumption of fruits and vegetables and different factors. Results: Between April and June 2013, a total of 10,735 participants completed the survey. Overall, 2.6% of Saudis aged 15 years or older met the CDC guidelines for daily consumption of fruits and vegetables. The likelihood of meeting the CDC guidelines increased with age; among women; among persons who graduated from elementary or high school or had a higher education; among residents of Makkah, Al Sharqia, Ha’il, or Jizan; among those who consumed at least two servings of meat or chicken per day; among those who visited a health care facility for a routine medical exam

  13. Smoking pattern among female college students in Dammam, Saudi Arabia

    OpenAIRE

    Koura, Manal R.; Ahlam F Al-Dossary; Bahnassy, Ahmed A.

    2011-01-01

    Background: Smoking is the most important avoidable cause of premature morbidity and mortality in the world. The estimated annual death rate of 4.9 million people in 1999 is expected to rise to 10 million by the 2020s and 2030s, 7 million of which will occur in developing countries. Aim: The aim of the present study was to estimate the prevalence of smoking and assess its pattern among non-medical female college students in Dammam, Saudi Arabia. Materials and Methods: A cross-sectional study ...

  14. Diffusion of the Adoption of Online Retailing in Saudi Arabia

    OpenAIRE

    AlGhamdi, Rayed

    2014-01-01

    Despite the fact that Saudi Arabia is a leading producer of oil and natural gas, a member of G-20, has the largest and fastest growth of ICT marketplaces in the Arab region, and is very wealthy, online retailing activities are not progressing at the same speed as its growing ICT marketplace. For this reason, the attitudes of retailers in companies at different stages of e-commerce maturity were investigated to determine what factors are causing this problem. The data collection included two s...

  15. Tertiary care availability and adolescent pregnancy characteristics in Saudi Arabia

    OpenAIRE

    Al-Kadri HM; Madkhali A; Al-Kadi MT; Bakhsh H; Alruwaili NN; Tamim HM

    2014-01-01

    Hanan M Al-Kadri,1 Azza Madkhali,1 Mohammed T Al-Kadi,2 Hanadi Bakhsh,1 Nourah N Alruwaili,2 Hani M Tamim21Department of Obstetrics and Gynecology, King Abdulaziz Medical City, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, 2King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Kingdom of Saudi ArabiaBackground: In this study, we aimed to assess the rate of adolescent delivery in a Saudi tertiary health care center and to investigate the association between maternal...

  16. Giant saltation on Mars.

    Science.gov (United States)

    Almeida, Murilo P; Parteli, Eric J R; Andrade, José S; Herrmann, Hans J

    2008-04-29

    Saltation, the motion of sand grains in a sequence of ballistic trajectories close to the ground, is a major factor for surface erosion, dune formation, and triggering of dust storms on Mars. Although this mode of sand transport has been matter of research for decades through both simulations and wind tunnel experiments under Earth and Mars conditions, it has not been possible to provide accurate measurements of particle trajectories in fully developed turbulent flow. Here we calculate the motion of saltating grains by directly solving the turbulent wind field and its interaction with the particles. Our calculations show that the minimal wind velocity required to sustain saltation on Mars may be surprisingly lower than the aerodynamic minimal threshold measurable in wind tunnels. Indeed, Mars grains saltate in 100 times higher and longer trajectories and reach 5-10 times higher velocities than Earth grains do. On the basis of our results, we arrive at general expressions that can be applied to calculate the length and height of saltation trajectories and the flux of grains in saltation under various physical conditions, when the wind velocity is close to the minimal threshold for saltation. PMID:18443302

  17. Ancient aliens on mars

    CERN Document Server

    Bara, Mike

    2013-01-01

    Best-selling author and Secret Space Program researcher Bara brings us this lavishly illustrated volume on alien structures on Mars. Was there once a vast, technologically advanced civilization on Mars, and did it leave evidence of its existence behind for humans to find eons later? Did these advanced extraterrestrial visitors vanish in a solar system wide cataclysm of their own making, only to make their way to Earth and start anew? Was Mars once as lush and green as the Earth, and teeming with life? Did Mars once orbit a missing member of the solar system, a "Super Earth” that vanished in a disaster that devastated life on Earth and Venus and left us only the asteroid belt as evidence of its once grand existence? Did the survivors of this catastrophe leave monuments and temples behind, arranged in a mathematical precision designed to teach us the Secret of a new physics that could lift us back to the stars? Does the planet have an automated defense shield that swallows up robotic probes if they wander int...

  18. Terra e Arte Project: Soils connecting Art and Education

    Science.gov (United States)

    Muggler, Cristine Carole; Rozenberg, Bianca; de Cássia Francisco, Talita; Gramacho de Oliveira, Elisa

    2015-04-01

    The "Terra e Arte" project was designed to combine science and art by approaching soil contents in basic education schools in Viçosa, Minas Gerais, Brazil. The project was developed to awake, sensitize and create awareness about soils and their importance to life and environment within school communities. It was proposed and realized by the Earth Sciences Museum Alexis Dorofeef (MCTAD) of the Federal University of Viçosa (UFV), as part of the celebrations of its 20th anniversary. Since all the schools of the town visit the museum at least once a year and most of them have received and carried out pedagogic projects on soil themes in the last 20 years, it was proposed to them to develop a soil subject with any of their groups and combine it with painting using soil materials. Each group interested in joining the project received a basic set of material to produce soil paints. They were expected to develop a soil theme and its contents for a few weeks and to finalize it with a figurative and textual collective creation that synthetized their learning. 16 of the 24 visited schools joined the project and realized it for an average of two months. During this time, the school groups visited the museum and/or borrowed the itinerant exposition on soils from the museum to work with in in the school community. At the end of the projects, the productions were presented at the Knowledge Market (Feira do Conhecimento) that happens every year in the central square of the town, as part of the National Week of Science and Technology. At the event, 58 works were presented by 14 schools, involving directly 700 pupils and their teachers. They approached themes from soil formation and properties to agroecology and urban occupation and impacts on the soils. 30 of the works were selected for a commemorative exposition and 12 were chosen for a table calendar 2014. The movement created around the project mobilized many people and had strong impact on the school communities, especially

  19. Mars Surface Environmental Issues

    Science.gov (United States)

    Charles, John

    2002-01-01

    Planetary exploration by astronauts will require extended periods of habitation on a planet's surface, under the influence of environmental factors that are different from those of Earth and the spacecraft that delivered the crew to the planet. Human exploration of Mars, a possible near-term planetary objective, can be considered a challenging scenario. Mission scenarios currently under consideration call for surface habitation periods of from 1 to 18 months on even the earliest expeditions. Methods: Environmental issues associated with Mars exploration have been investigated by NASA and the National Space Biomedical Research Institute (NSBRI) as part of the Bioastronautics Critical Path Roadmap Project (see http ://criticalpath.jsc.nasa.gov). Results: Arrival on Mars will immediately expose the crew to gravity only 38% of that at Earth's surface in possibly the first prolonged exposure to gravity other than the 1G of Earth's surface and the zero G of weightless space flight, with yet unknown effects on crew physiology. The radiation at Mars' surface is not well documented, although the planet's bulk and even its thin atmosphere may moderate the influx of galactic cosmic radiation and energetic protons from solar flares. Secondary radiation from activated components of the soil must also be considered. Ultrafine and larger respirable and nonrespirable particles in Martian dust introduced into the habitat after surface excursions may induce pulmonary inflammation exacerbated by the additive reactive and oxidizing nature of the dust. Stringent decontamination cannot eliminate mechanical and corrosive effects of the dust on pressure suits and exposed machinery. The biohazard potential of putative indigenous Martian microorganisms may be assessed by comparison with analog environments on Earth. Even in their absence, human microorganisms, if not properly controlled, can be a threat to the crew's health. Conclusions: Mars' surface offers a substantial challenge to the

  20. [MaRS Project

    Science.gov (United States)

    Aruljothi, Arunvenkatesh

    2016-01-01

    The Space Exploration Division of the Safety and Mission Assurances Directorate is responsible for reducing the risk to Human Space Flight Programs by providing system safety, reliability, and risk analysis. The Risk & Reliability Analysis branch plays a part in this by utilizing Probabilistic Risk Assessment (PRA) and Reliability and Maintainability (R&M) tools to identify possible types of failure and effective solutions. A continuous effort of this branch is MaRS, or Mass and Reliability System, a tool that was the focus of this internship. Future long duration space missions will have to find a balance between the mass and reliability of their spare parts. They will be unable take spares of everything and will have to determine what is most likely to require maintenance and spares. Currently there is no database that combines mass and reliability data of low level space-grade components. MaRS aims to be the first database to do this. The data in MaRS will be based on the hardware flown on the International Space Stations (ISS). The components on the ISS have a long history and are well documented, making them the perfect source. Currently, MaRS is a functioning excel workbook database; the backend is complete and only requires optimization. MaRS has been populated with all the assemblies and their components that are used on the ISS; the failures of these components are updated regularly. This project was a continuation on the efforts of previous intern groups. Once complete, R&M engineers working on future space flight missions will be able to quickly access failure and mass data on assemblies and components, allowing them to make important decisions and tradeoffs.

  1. TERRA: a computer code for simulating the transport of environmentally released radionuclides through agriculture

    International Nuclear Information System (INIS)

    TERRA is a computer code which calculates concentrations of radionuclides and ingrowing daughters in surface and root-zone soil, produce and feed, beef, and milk from a given deposition rate at any location in the conterminous United States. The code is fully integrated with seven other computer codes which together comprise a Computerized Radiological Risk Investigation System, CRRIS. Output from either the long range (> 100 km) atmospheric dispersion code RETADD-II or the short range (<80 km) atmospheric dispersion code ANEMOS, in the form of radionuclide air concentrations and ground deposition rates by downwind location, serves as input to TERRA. User-defined deposition rates and air concentrations may also be provided as input to TERRA through use of the PRIMUS computer code. The environmental concentrations of radionuclides predicted by TERRA serve as input to the ANDROS computer code which calculates population and individual intakes, exposures, doses, and risks. TERRA incorporates models to calculate uptake from soil and atmospheric deposition on four groups of produce for human consumption and four groups of livestock feeds. During the environmental transport simulation, intermediate calculations of interception fraction for leafy vegetables, produce directly exposed to atmospherically depositing material, pasture, hay, and silage are made based on location-specific estimates of standing crop biomass. Pasture productivity is estimated by a model which considers the number and types of cattle and sheep, pasture area, and annual production of other forages (hay and silage) at a given location. Calculations are made of the fraction of grain imported from outside the assessment area. TERRA output includes the above calculations and estimated radionuclide concentrations in plant produce, milk, and a beef composite by location

  2. Cross-calibration of the Oceansat-2 Ocean Colour Monitor (OCM) with Terra and Aqua MODIS

    Science.gov (United States)

    Angal, Amit; Brinkmann, Jake; Kumar, A. Senthil; Xiong, Xiaoxiong

    2016-05-01

    The Ocean Colour Monitor (OCM) sensor on-board the Oceansat-2 spacecraft has been operational since its launch in September, 2009. The Oceansat 2 OCM primary design goal is to provide continuity to Oceansat-1 OCM to obtain information regarding various ocean-colour variables. OCM acquires Earth scene measurements in eight multi-spectral bands in the range from 402 to 885 nm. The MODIS sensor on the Terra and Aqua spacecraft has been successfully operating for over a decade collecting measurements of the earth's land, ocean surface and atmosphere. The MODIS spectral bands, designed for land and ocean applications, cover the spectral range from 412 to 869 nm. This study focuses on comparing the radiometric calibration stability of OCM using near-simultaneous TOA measurements with Terra and Aqua MODIS acquired over the Libya 4 target. Same-day scene-pairs from all three sensors (OCM, Terra and Aqua MODIS) between August, 2014 and September, 2015 were chosen for this analysis. On a given day, the OCM overpass is approximately an hour after the Terra overpass and an hour before the Aqua overpass. Due to the orbital differences between Terra and Aqua, MODIS images the Libya 4 site at different scan-angles on a given day. Some of the high-gain ocean bands for MODIS tend to saturate while viewing the bright Libya 4 target, but bands 8-10 (412 nm - 486 nm) provide an unsaturated response and are used for comparison with the spectrally similar OCM bands. All the standard corrections such as bidirectional reflectance factor (BRDF), relative spectral response mismatch, and impact for atmospheric water-vapor are applied to obtain the reflectance differences between OCM and the two MODIS instruments. Furthermore, OCM is used as a transfer radiometer to obtain the calibration differences between Terra and Aqua MODIS reflective solar bands.

  3. TERRA: a computer code for simulating the transport of environmentally released radionuclides through agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Baes, C.F. III; Sharp, R.D.; Sjoreen, A.L.; Hermann, O.W.

    1984-11-01

    TERRA is a computer code which calculates concentrations of radionuclides and ingrowing daughters in surface and root-zone soil, produce and feed, beef, and milk from a given deposition rate at any location in the conterminous United States. The code is fully integrated with seven other computer codes which together comprise a Computerized Radiological Risk Investigation System, CRRIS. Output from either the long range (> 100 km) atmospheric dispersion code RETADD-II or the short range (<80 km) atmospheric dispersion code ANEMOS, in the form of radionuclide air concentrations and ground deposition rates by downwind location, serves as input to TERRA. User-defined deposition rates and air concentrations may also be provided as input to TERRA through use of the PRIMUS computer code. The environmental concentrations of radionuclides predicted by TERRA serve as input to the ANDROS computer code which calculates population and individual intakes, exposures, doses, and risks. TERRA incorporates models to calculate uptake from soil and atmospheric deposition on four groups of produce for human consumption and four groups of livestock feeds. During the environmental transport simulation, intermediate calculations of interception fraction for leafy vegetables, produce directly exposed to atmospherically depositing material, pasture, hay, and silage are made based on location-specific estimates of standing crop biomass. Pasture productivity is estimated by a model which considers the number and types of cattle and sheep, pasture area, and annual production of other forages (hay and silage) at a given location. Calculations are made of the fraction of grain imported from outside the assessment area. TERRA output includes the above calculations and estimated radionuclide concentrations in plant produce, milk, and a beef composite by location.

  4. Developing an Updated, Integrated Understanding of Mars

    OpenAIRE

    Ehlmann, Bethany; Beaty, David; Meyer, Michael

    2014-01-01

    More than 650 scientists from 21 countries gathered in mid‐July at the California Institute of Technology (Caltech) to debate and examine the status of our exploration of the Red Planet. Since the Seventh International Conference on Mars in 2007, seven Mars missions— Mars Odyssey, Mars Exploration Rovers (Spirit/Opportunity), Mars Express, Mars Reconnaissance Orbiter, Phoenix, and Mars Science Laboratory (Curiosity)—have been returning data, augmented by telescop...

  5. The genome of the fungal-interactive soil bacterium Burkholderia terrae BS001 : A plethora of outstanding interactive capabilities unveiled

    NARCIS (Netherlands)

    Haq, Irshad Ul; Graupner, Katharina; Nazir, Rashid; van Elsas, Jan Dirk

    2014-01-01

    Burkholderia terrae strain BS001, obtained as an inhabitant of the mycosphere of Laccaria proxima (a close relative of Lyophyllum sp. strain Karsten), actively interacts with Lyophyllum sp. strain Karsten. We here summarize the remarkable ecological behavior of B. terrae BS001 in the mycosphere and

  6. 75 FR 1052 - Terra-Gen Dixie Valley, LLC; TGP Dixie Development Company, LLC; New York Canyon, LLC; Notice of...

    Science.gov (United States)

    2010-01-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Terra-Gen Dixie Valley, LLC; TGP Dixie Development Company, LLC; New York Canyon, LLC; Notice of Filing December 30, 2009. Take notice that on December 24, 2009, Terra-Gen...

  7. 75 FR 5780 - Green Borders Geothermal, LLC, Complainant, v. Terra-Gen Dixie Valley, LLC, Respondent; Notice of...

    Science.gov (United States)

    2010-02-04

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Green Borders Geothermal, LLC, Complainant, v. Terra-Gen Dixie Valley, LLC... Geothermal, LLC (Green Borders) filed a formal complaint against Terra-Gen Dixie Valley, LLC (f/k/a...

  8. Uso da terra e a qualidade microbiana de agregados de um Latossolo Vermelho-Amarelo

    OpenAIRE

    Rogério Melloni; Eliane Guimarães Pereira Melloni; Lucas Lopes Vieira

    2013-01-01

    A maioria dos estudos relacionados à agregação do solo associa o efeito de manejos ou tipos de uso da terra ao teor de matéria orgânica. No entanto, a avaliação de microrganismos e seus processos, feita diretamente em estruturas indeformadas do solo, permite maior entendimento do real efeito de diferentes tipos de manejos exercidos sobre esse. Assim, o objetivo deste trabalho foi avaliar modificações impostas por diferentes tipos de uso da terra (pastagem, mata de eucalipto, mata com araucári...

  9. Use of TerraSAR-X data to retrieve soil moisture over bare soil agricultural fields

    OpenAIRE

    Baghdadi, N.; Aubert, M.; Zribi, M.

    2012-01-01

    The retrieval of the bare soil moisture content from TerraSAR-X data is discussed using empirical approaches. Two cases were evaluated: 1) one image at low or high incidence angle and 2) two images, one at low incidence and one at high incidence. This study shows by using three databases collected between 2008 and 2010 over two study sites in France (Orgeval and Villamblain) that TerraSAR-X is a good remote sensing tool for the retrieving of surface soilmoisture with accuracy of about 3% (rms...

  10. Detection of Toxic Metalsin Lipsticks Products in Riyadh, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Khairia Mohamed Ahmed Al-Qahtani

    2016-08-01

    Full Text Available Background and aims: Since the dawn of civilization cosmetics have constituted a part of routine body care not only by the upper strata of society but also by middle and low class people. Heavy metals contamination in cosmetic products is becoming an important health problem in both worldwide and locally at the level of the Kingdom of Saudi Arabia (KSA.The aim of this study was tostudy.Quantitatively estimated heavy metals “lead, cadmium, mercury and Arsenic” using graphite.Methods: total of 21 popular brands used lipstick products sold in Riyadh market samples from 3 different types of lipsticks frequently used among females in Saudi Arabia was digested. The digested samples were analyzed for lead, cadmium, mercury and Arsenic using graphite furnace- atomic absorption spectrometry. Results:the mercury concentration was high followed by arsenic and cadmium, finally lead. The results indicate that the toxic heavy metals in all the samples were below the US FDA and SFDA permissible limits for cosmetic products with the exception the mercury content in some lipstick samples was higher than SFDA. There was no significant difference among the lipsticks in price categories.Conclusion: Continuous use and possible unintended ingestion of these toxic heavy metals, though in low levels in the cosmetics, may pose potential health risk due to their bioaccumulation in body organs.

  11. Biodiversity characteristics of Teucrium polium species in Saudi Arabia.

    Science.gov (United States)

    Bukhari, Najat A; Al-Otaibi, Reem A; Ibhrahim, Mohammed M

    2015-03-01

    Teucrium (Lamiaceae) is a large and polymorphic genus distributed mainly in Europe, North Africa and in the temperate parts of Asia. In this study, the anatomical features of the leaf and stem of Teucrium polium are investigated. Teucrium has 19 taxa in Iran, which mainly grow in the Irano-Turanian region between 700 and 2000 m above sea level. T. polium belonging to sect. Polium, is a perennial herb growing on Lorestan province. The leaves clearly exhibit xeromorphy due to features such as thick cuticle layer, thick outer epidermal cell wall, high density of trichomes and thick palisade layer of the mesophyll. Anatomical studies on T. polium revealed that the stem shares the general characteristics of the Labiatae family. The aim of our approach was to study the morphological and taxonomical parameters for T. polium in Saudi Arabia. The results of this study showed that there was no influence of environment on the structure of stomata and trichomes as studying species with T . polium. In conclusion our study shows we have studied the geographical distribution of the species in Saudi Arabia and in the world.

  12. Holocene and Pleistocene pluvial periods in Yemen, southern Arabia

    Science.gov (United States)

    Fleitmann, Dominik; Burns, Stephen J.; Pekala, Marek; Mangini, Augusto; Al-Subbary, Abdulkarim; Al-Aowah, Mohammad; Kramers, Jan; Matter, Albert

    2011-04-01

    Arabia is an important potential pathway for the dispersal of Homo sapiens ("out of Africa"). Yet, because of its arid to hyper-arid climate humans could only migrate across southern Arabia during pluvial periods when environmental conditions were favorable. However, knowledge on the timing of Arabian pluvial periods prior to the Holocene is mainly based on a single and possibly incomplete speleothem record from Hoti Cave in Northern Oman. Additional terrestrial records from the Arabian Peninsula are needed to confirm the Hoti Cave record. Here we present a new speleothem record from Mukalla Cave in southern Yemen. The Mukalla Cave and Hoti Cave records clearly reveal that speleothems growth occurred solely during peak interglacial periods, corresponding to Marine Isotope Stages (MIS) 1 (early to mid-Holocene), 5.1, 5.3, 5.5 (Eemian), 7.1, 7.5 and 9. Of these humid periods, highest precipitation occurred during MIS 5.5 and lowest during early to middle Holocene.

  13. Prevalence of Musculoskeletal Pain in Construction Workers in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Ahmad Alghadir

    2015-01-01

    Full Text Available The objective of this study was to find out the prevalence, characteristics, and distribution of musculoskeletal pain among construction workers in Saudi Arabia. A questionnaire about musculoskeletal pain in different parts of the body was completed by 165 construction workers from the construction industries in Dammam and Riyadh cities. The descriptive data were analyzed using chi-square test. The level of statistical significance was set at P<0.05. Eighty (48.5% of the responding workers had pain in neck, shoulders, lower back, hand, knee, or ankle. The majority of respondents had low back pain (50% followed by knee pain (20%. The average intensity of pain at all sites during activity and rest was 6.65 and 3.59, respectively. Thirty-four (42.5% respondents had dull aching pain and 24 (30% had cramping pain. There was an association between years of experience, duration of break during work, and use of protective equipment with the prevalence of musculoskeletal pain in construction workers (P<0.05. Most of the workers complaining of pain got medical treatment (62.5% and only 25% received physical therapy. It can be concluded from this study that the prevalence of musculoskeletal pain among construction workers in Saudi Arabia is high.

  14. Radon concentration measurements in the desert caves of Saudi Arabia

    International Nuclear Information System (INIS)

    Beneath the harsh deserts of Saudi Arabia lie dark chambers and complex mazes filled with strange shapes and wondrous beauty. Radon concentration measurements have been carried out in the desert caves of Al-Somman Plateau in the Eastern Province of Saudi Arabia. Passive radon dosimeters, based on alpha particle etch track detectors with an inlet filter, were used in this study. A total of 59 dosimeters were placed in five caves for a period of six months. Out of 59 dosimeters, 37 could be collected for analysis. Measurements showed significant variations in radon concentrations in caves depending upon their natural ventilation. The results of the study show that the average radon concentration in the different caves ranges from 74 up to 451Bqm-3. The average radon concentration in four of the caves was low in the range 74-114Bqm-3. However, one cave showed an average radon concentration of 451Bqm-3. Radon is not a problem for tourists in the majority of caves. However, sometimes it may imply some limitation to the working time of guides

  15. Sustainability Assessment of Higher Education Institutions in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Habib M. Alshuwaikhat

    2016-08-01

    Full Text Available Universities are paramount change drivers in bringing about a culture of sustainability in society by setting themselves up as models and nurseries for sustainable development. Thus, assessment of sustainability integration within universities is key to their impact on sustainable development. This study conducted an assessment of different public sector universities of Saudi Arabia based on five components: (i Teaching and Curriculum; (ii Research and Scholarship; (iii Campus Operations; (iv Management and Community; and (v Financial Management. The sustainability assessment questionnaire (SAQ was utilized as a tool to discern the component-wise sustainability assessment for Saudi universities. The outcomes of the survey reveal that, in stark contrast with the universities of the developed world, offerings of sustainability relevant academic courses in Saudi Arabia are still lacking. Most Saudi universities still need to integrate research and scholarship in the area of sustainability; sustainable-campus operations in the current scenario are not sufficient. The results also reveal that sustainability-related projects are not prioritized within universities and sustainable financial management practices are not significant. This article concludes by proposing some recommendations emphasizing the importance of adopting sustainability practices in Saudi universities.

  16. Crude oil price fluctuations and Saudi Arabia's behaviour

    International Nuclear Information System (INIS)

    This study attempts to explain why crude oil prices fluctuate, the main cause being the quota regime, which characterises the OPEC agreements. Given that the Saudi oil supply is inelastic in the short term, a shock in the oil market is accommodated by an immediate price change. By contrast, a dominant firm behaviour in the long term causes an output change, which is accompanied by a smaller price change. This explains why oil prices overshoot. The results of a general equilibrium model applied to Saudi Arabia support this analysis. They also indicate that Saudi Arabia does not have any incentive for altering the crude oil market equilibrium with either positive or negative supply shocks, as its welfare declines; and that it has an incentive (disincentive) for intervening if a negative (positive) demand shock hits the crude oil market. A second set of simulations is designed to understand what kind of OECD policy might help to bring down prices. A tax cut would worsen the situation, whereas policies that can increase the price elasticity of demand seem to be very effective. (Author)

  17. Biodiversity characteristics of Teucrium polium species in Saudi Arabia.

    Science.gov (United States)

    Bukhari, Najat A; Al-Otaibi, Reem A; Ibhrahim, Mohammed M

    2015-03-01

    Teucrium (Lamiaceae) is a large and polymorphic genus distributed mainly in Europe, North Africa and in the temperate parts of Asia. In this study, the anatomical features of the leaf and stem of Teucrium polium are investigated. Teucrium has 19 taxa in Iran, which mainly grow in the Irano-Turanian region between 700 and 2000 m above sea level. T. polium belonging to sect. Polium, is a perennial herb growing on Lorestan province. The leaves clearly exhibit xeromorphy due to features such as thick cuticle layer, thick outer epidermal cell wall, high density of trichomes and thick palisade layer of the mesophyll. Anatomical studies on T. polium revealed that the stem shares the general characteristics of the Labiatae family. The aim of our approach was to study the morphological and taxonomical parameters for T. polium in Saudi Arabia. The results of this study showed that there was no influence of environment on the structure of stomata and trichomes as studying species with T . polium. In conclusion our study shows we have studied the geographical distribution of the species in Saudi Arabia and in the world. PMID:25737650

  18. Awareness of cardiovascular disease in eastern Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Nadira A Al-Baghli

    2010-01-01

    Full Text Available Objective: To estimate the awareness of cardiovascular disease (CVD and their determinants in a screening campaign in the eastern province of Saudi Arabia. Materials and Methods: All national residents in the eastern province of Saudi Arabia aged 30 years and above, were invited to participate in a screening campaign for the early detection of diabetes and hypertension at more than 300 examination posts throughout the eastern province. A pre-structured questionnaire was designed to collect data on age, gender, marital status, education level, occupation, lifestyle habits, and history of heart attack, angina, arterial disease, stroke, and transient ischemic attack. Weight, height, blood pressure, and glucose concentration were measured. Results: Out of 197,681 participants, 5372 (2.7% were aware of a history of a CVD. The prevalence correlated well with age. It was higher in women, widows, and subjects with lower level of education. More than 75% of affected subjects had two or more risk factors. Conclusion: A substantial proportion of those with a history of CVD had multiple risk factors, necessitating an effective, focused policy for the prevention and treatment. Increased effort is required to promote an awareness of cardiac disease and also probably target primary care providers involved in the screening process.

  19. Predictors of smoking among male college students in Saudi Arabia.

    Science.gov (United States)

    Almogbel, Y S; Abughosh, S M; Almogbel, F S; Alhaidar, I A; Sansgiry, S S

    2013-11-01

    Identifying the predictors of smoking in one of the top cigarette-consuming countries in the world is a vital step in smoking prevention. A cross-sectional study assessed the predictors of smoking in a cohort of male students in 3 universities in Saudi Arabia. A pre-tested, validated questionnaire was used to determine sociodemographic characteristics, academic performance, peers' smoking, and presence of a smoker within the family. Of the 337 participants, 30.9% were current smokers (smoked 1 or more cigarettes within the last 30 days). Lower academic performance (OR = 2.29, 95% CI: 1.02-5.17), peer smoking (OR = 4.14, 95% CI: 1.53-11.3) and presence of other smokers in the family (OR = 2.77, 95% CI: 1.37-5.64) were the significant predictors of smoking status identified using multiple logistic regression analysis. These findings highlight the influence of family and peer pressure in initiating cigarette use among the youth of Saudi Arabia. PMID:24673080

  20. Prospect of Neem Plantation at Arafat, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    M. A. U Mridha

    2014-04-01

    Full Text Available Neem (Azadirachta indicaA.Juss. is a multipurpose agroforestry tree that is well adapted to a wide range of climatic and soil conditions and has gained worldwide recognition for its pharmaceutical and pesticidal properties.The world's largest pure Neem plantations are available in the plains of Arafat, Saudi Arabia where 50,000 thousands Neem trees were planted to provide shade from the blazing summer sun for the millions of Hajis (Muslim pilgrims. Sporadic mature Neem trees are also found in Medinah, Taif and elsewhereof the Kingdom. The Neem tree is adapted to Arafat under harsh climatic conditions of Saudi Arabia and the plantation may be extended to other parts of the Kingdom as a avenue tree and also to minimize the desertification under changing climatic conditions and to improve the environmental condition of the country. At Arafat mixed plantations may be advocated to save the present plantation which may come from climate change as well as pest and diseases problems. So care must be taken to monitor the diseases of Neem tree at Arafat on a regularbasis. Because of insufficient growth of Neem at Arafat the methods of green cultivation with microbial inoculants, organic fertilizers, mycotrophic green manure plants may be practiced for successful plantation.

  1. Preliminary assessment of atmospheric turbidity at Dhahran, Saudi Arabia

    Energy Technology Data Exchange (ETDEWEB)

    Abdelrahman, M.A.; Nimmo, B.G.

    1984-01-01

    Direct and total radiation measurements carried out over several years in Dhahran, Saudi Arabia in support of the Research Institute's solar energy programs have indicated a relatively large diffuse radiation component. This is primarily due to airborne particulates carried aloft by the prevailing winds in a desert environment and occurs particularly during the Shamal (north wind) sandstorm season. As a first step in quantifying the nature of this atmospheric turbidity, spectral beam solar radiation measurements for the period July 1980 to June 1981 were made in Dhahran, Saudi Arabia (Lat. 26/sup 0/ 23', Long. 50/sup 0/ 00'), using broad-band filter techniques. Schott filters (OG1, RG2 and RG8) arranged on an automatically rotated disk mounted on an Eppley Normal Incidence Pyrheliometer were used for the measurements. The Beer-Lambert relation was used to calculate optical depths from which values of the Angstroem Coefficient of Turbidity, ..beta.., were obtained for the wavelength exponent, ..cap alpha.. = 1.3. In addition, Herovanu's method was used to obtain ..cap alpha.. and ..beta.. values for each month. The 12-month average values of ..beta.. and ..cap alpha.. were 0.22 and 1.28, respectively. 12 references, 3 figures, 1 table.

  2. Gender inequity in Saudi Arabia and its role in public health.

    Science.gov (United States)

    Mobaraki, A E H; Söderfeldt, B

    2010-01-01

    In Saudi Arabia, local interpretations of Islamic laws and social norms have a negative impact on the health and well-being of women. The objective of this literature review was to discuss gender inequity in Saudi Arabia and its relation to public health. Despite the scarcity of recent statistics and information regarding gender inequity in Saudi Arabia, this review is an attempt to explore this sensitive issue in this country. Women's roles and rights in Saudi society were examined, including education, marriage, polygamy, fertility, job opportunities, car driving and identification cards. Further research to assess knowledge, attitudes and practices towards health care of Saudi men and women is recommended.

  3. Gender inequity in Saudi Arabia and its role in public health.

    Science.gov (United States)

    Mobaraki, A E H; Söderfeldt, B

    2010-01-01

    In Saudi Arabia, local interpretations of Islamic laws and social norms have a negative impact on the health and well-being of women. The objective of this literature review was to discuss gender inequity in Saudi Arabia and its relation to public health. Despite the scarcity of recent statistics and information regarding gender inequity in Saudi Arabia, this review is an attempt to explore this sensitive issue in this country. Women's roles and rights in Saudi society were examined, including education, marriage, polygamy, fertility, job opportunities, car driving and identification cards. Further research to assess knowledge, attitudes and practices towards health care of Saudi men and women is recommended. PMID:20214168

  4. Icebergs on early Mars

    Science.gov (United States)

    Uceda, E.; Fairen, A.; Woodworth-Lynas, C.; Palmero Rodriguez, A.

    2015-12-01

    The smooth topography of the Martian northern lowlands has been classically equated to an ancient ocean basin. The High-Resolution Imaging Science Experiment (HiRISE) onboard the Mars Reconnaissance Orbiter (MRO) is providing unprecedented images of the Martian surface at scales of 25 to 32 cm per pixel. The analysis of this high-resolution imaging reveals the presence of three differentiated geomorphologies throughout the northern lowlands of Mars and the Hellas basin, which are informative of the presence of icebergs floating in ancient oceans and/or seas. These morphologies are: (i) scattered scour marks, including curvilinear furrows several km long and some meters deep; (ii) boulders ranging in size from 0.5 m to ~2 m in diameter, distributed forming clusters with sizes from several hundred meters to 1-2 km; and (iii) flat-topped and conical circular fractured mounds. The association of plough marks, clusters of boulders and mounds on the northern plains of Mars can be related to the dual processes of ice keel scouring and ice rafting of both glacial and non-glacial detritus by a floating ice canopy and icebergs. These processes are well documented on Earth and result in distinct morphologies on the ocean floor, which are analogous to features observed in the Martian basins. Importantly, the features are located in elevated areas of the northern plains and Hellas, near the dichotomy boundary and on local topographic highs. Such distribution is expected, as these relatively shoal areas are where the iceberg-related features should occur on Mars: these areas had shallow water depths, less than the iceberg's keel depth, and therefore keels reached through the full depth of the water column to impinge on the sediments below. The presence of icebergs floating in cold oceans early in Mars' history imply the occurrence of continental glaciers forming in the highlands and streaming northward towards the lowlands, and towards the Hellas and Argyre Basins. Glacier

  5. Happy Mars Solstice!

    Science.gov (United States)

    2008-01-01

    This image was acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager (SSI) in the late afternoon of the 30th Martian day of the mission, or Sol 30 (June 25, 2008). This is hours after the beginning of Martian northern summer. SSI used its natural-color filters, therefore the color is the color you would see on Mars. The image shows shadows from the SSI (left) and from the meteorological station mast (right) stretching toward the east as the sun dropped low in the west. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver

  6. The politics of Mars

    Science.gov (United States)

    Schmitt, Harrison H.

    1986-01-01

    A discussion is presented comparing past and present major accomplishments of the U.S. and the Soviet Union in space. It concludes that the Soviets are presently well ahead of the U.S. in several specific aspects of space accomplishment and speculates that the Soviet strategy is directed towards sending a man to the vicinity of Mars by the end of this century. A major successful multinational space endeavor, INTELSAT, is reviewed and it is suggested that the manned exploration of Mars offers a unique opportunity for another such major international cooperative effort. The current attitude of U.S. leadership and the general public is assessed as uniformed or ambivalent about the perceived threat of Soviet dominance in space.

  7. The Exploration of Mars by Humans: Why Mars? Why Humans?

    Science.gov (United States)

    Levine, Joel S.

    2011-01-01

    As we commemorate the 50th anniversary of Yuri Gagarin's historic flight in 1961, the first flight of a human in space, plans are underway for another historic human mission. Plans are being developed for a human mission to Mars. Once we reach Mars, the human species will become the first two-planet species. Both the Bush Administration (in 2004) and the Obama Administration (in 2010) proposed a human mission to Mars as a national goal of the United States.

  8. A synthesis of Martian aqueous mineralogy after 1 Mars year of observations from the Mars Reconnaissance Orbiter

    Science.gov (United States)

    Murchie, S.L.; Mustard, J.F.; Ehlmann, B.L.; Milliken, R.E.; Bishop, J.L.; McKeown, N.K.; Noe Dobrea, E.Z.; Seelos, F.P.; Buczkowski, D.L.; Wiseman, S.M.; Arvidson, R. E.; Wray, J.J.; Swayze, G.; Clark, R.N.; Des Marais, D.J.; McEwen, A.S.; Bibring, J.-P.

    2009-01-01

    Martian aqueous mineral deposits have been examined and characterized using data acquired during Mars Reconnaissance Orbiter's (MRO) primary science phase, including Compact Reconnaissance Imaging Spectrometer for Mars hyperspectral images covering the 0.4-3.9 ??m wavelength range, coordinated with higher-spatial resolution HiRISE and Context Imager images. MRO's new high-resolution measurements, combined with earlier data from Thermal Emission Spectrometer; Thermal Emission Imaging System; and Observatoire pour la Min??ralogie, L'Eau, les Glaces et l'Activiti?? on Mars Express, indicate that aqueous minerals are both diverse and widespread on the Martian surface. The aqueous minerals occur in 9-10 classes of deposits characterized by distinct mineral assemblages, morphologies, and geologic settings. Phyllosilicates occur in several settings: in compositionally layered blankets hundreds of meters thick, superposed on eroded Noachian terrains; in lower layers of intracrater depositional fans; in layers with potential chlorides in sediments on intercrater plains; and as thousands of deep exposures in craters and escarpments. Carbonate-bearing rocks form a thin unit surrounding the Isidis basin. Hydrated silica occurs with hydrated sulfates in thin stratified deposits surrounding Valles Marineris. Hydrated sulfates also occur together with crystalline ferric minerals in thick, layered deposits in Terra Meridiani and in Valles Marineris and together with kaolinite in deposits that partially infill some highland craters. In this paper we describe each of the classes of deposits, review hypotheses for their origins, identify new questions posed by existing measurements, and consider their implications for ancient habitable environments. On the basis of current data, two to five classes of Noachian-aged deposits containing phyllosilicates and carbonates may have formed in aqueous environments with pH and water activities suitable for life. Copyright 2009 by the American

  9. Organics on Mars?

    Science.gov (United States)

    ten Kate, Inge L

    2010-01-01

    Organics are expected to exist on Mars based on meteorite infall, in situ production, and any possible biological sources. Yet they have not been detected on the martian surface; are they there, or are we not capable enough to detect them? The Viking gas chromatograph-mass spectrometer did not detect organics in the headspace of heated soil samples with a detection limit of parts per billion. This null result strongly influenced the interpretation of the reactivity seen in the Viking biology experiments and led to the conclusion that life was not present and, instead, that there was some chemical reactivity in the soil. The detection of perchlorates in the martian soil by instruments on the Phoenix lander and the reports of methane in the martian atmosphere suggest that it may be time to reconsider the question of organics. The high-temperature oxidizing properties of perchlorate will promote combustion of organics in pyrolytic experiments and may have affected the ability of both Phoenix's organic analysis experiment and the Viking mass spectrometer experiments to detect organics. So the question of organics on Mars remains open. A primary focus of the upcoming Mars Science Laboratory will be the detection and identification of organic molecules by means of thermal volatilization, followed by gas chromatography-mass spectrometry--as was done on Viking. However, to enhance organic detectability, some of the samples will be processed with liquid derivatization agents that will dissolve organics from the soil before pyrolysis, which may separate them from the soil perchlorates. Nonetheless, the problem of organics on Mars is not solved, and for future missions other organic detection techniques should therefore be considered as well.

  10. MARS Flight Engineering Status

    Energy Technology Data Exchange (ETDEWEB)

    Fast, James E.; Dorow, Kevin E.; Morris, Scott J.; Thompson, Robert C.; Willett, Jesse A.

    2010-04-06

    The Multi-sensor Airborne Radiation Survey Flight Engineering project (MARS FE) has designed a high purity germanium (HPGe) crystal array for conducting a wide range of field measurements. In addition to the HPGe detector system, a platform-specific shock and vibration isolation system and environmental housing have been designed to support demonstration activities in a maritime environment on an Unmanned Surface Vehicle (USV). This report describes the status of the equipment as of the end of FY09.

  11. Sustainable Mars Sample Return

    Science.gov (United States)

    Alston, Christie; Hancock, Sean; Laub, Joshua; Perry, Christopher; Ash, Robert

    2011-01-01

    The proposed Mars sample return mission will be completed using natural Martian resources for the majority of its operations. The system uses the following technologies: In-Situ Propellant Production (ISPP), a methane-oxygen propelled Mars Ascent Vehicle (MAV), a carbon dioxide powered hopper, and a hydrogen fueled balloon system (large balloons and small weather balloons). The ISPP system will produce the hydrogen, methane, and oxygen using a Sabatier reactor. a water electrolysis cell, water extracted from the Martian surface, and carbon dioxide extracted from the Martian atmosphere. Indigenous hydrogen will fuel the balloon systems and locally-derived methane and oxygen will fuel the MAV for the return of a 50 kg sample to Earth. The ISPP system will have a production cycle of 800 days and the estimated overall mission length is 1355 days from Earth departure to return to low Earth orbit. Combining these advanced technologies will enable the proposed sample return mission to be executed with reduced initial launch mass and thus be more cost efficient. The successful completion of this mission will serve as the next step in the advancement of Mars exploration technology.

  12. Mars Rocket Propulsion System

    Science.gov (United States)

    Zubrin, Robert; Harber, Dan; Nabors, Sammy

    2008-01-01

    A report discusses the methane and carbon monoxide/LOX (McLOx) rocket for ascent from Mars as well as other critical space propulsion tasks. The system offers a specific impulse over 370 s roughly 50 s higher than existing space-storable bio-propellants. Current Mars in-situ propellant production (ISPP) technologies produce impure methane and carbon monoxide in various combinations. While separation and purification of methane fuel is possible, it adds complexity to the propellant production process and discards an otherwise useful fuel product. The McLOx makes such complex and wasteful processes unnecessary by burning the methane/CO mixtures produced by the Mars ISPP systems without the need for further refinement. Despite the decrease in rocket-specific impulse caused by the CO admixture, the improvement offered by concomitant increased propellant density can provide a net improvement in stage performance. One advantage is the increase of the total amount of propellant produced, but with a decrease in mass and complexity of the required ISPP plant. Methane/CO fuel mixtures also may be produced by reprocessing the organic wastes of a Moon base or a space station, making McLOx engines key for a human Lunar initiative or the International Space Station (ISS) program. Because McLOx propellant components store at a common temperature, very lightweight and compact common bulkhead tanks can be employed, improving overall stage performance further.

  13. On Target to Mars

    Science.gov (United States)

    Cheng, Yang

    2007-01-01

    This viewgraph presentation reviews the use of Descent Image Motion Estimation System (DIMES) for the descent of a spacecraft onto the surface of Mars. In the past this system was used to assist in the landing of the MER spacecraft. The overall algorithm is reviewed, and views of the hardware, and views from Spirit's descent are shown. On Spirit, had DIMES not been used, the impact velocity would have been at the limit of the airbag capability and Spirit may have bounced into Endurance Crater. By using DIMES, the velocity was reduced to well within the bounds of the airbag performance and Spirit arrived safely at Mars. Views from Oppurtunity's descent are also shown. The system to avoid and detect hazards is reviewed next. Landmark Based Spacecraft Pinpoint Landing is also reviewed. A cartoon version of a pinpoint landing and the various points is shown. Mars s surface has a large amount of craters, which are ideal landmarks . According to literatures on Martian cratering, 60 % of Martian surface is heavily cratered. The ideal (craters) landmarks for pinpoint landing will be between 1000 to 50 meters in diagonal The ideal altitude for position estimation should greater than 2 km above the ground. The algorithms used to detect and match craters are reviewed.

  14. Unsteady saltation on Mars

    Science.gov (United States)

    Wang, Ping; Zheng, Xiaojing

    2015-11-01

    Saltation is an important process on Mars, as it contributes to dust raising, bedform dynamics, and aeolian abrasion. Lander measurements and mesoscale meteorological models suggest that winds in the Martian atmosphere rarely exceed the fluid threshold value that is necessary to aerodynamically initiate saltation, a fact in stark contrast to the existence of dunes and ripples on the planet, many of which are in an active state of migration. In an attempt to reconcile these observations, we perform an unsteady simulation with a simple turbulence model to calculate the saltation transport rate. Sinusoidal wind variations are imposed on the saltation layer. The numerical simulations verify that gusty transport is one of the main manifestations of Martian sediment transport events. A formula for the saltation transport rate is reported, Qm ∼(u∗ -u∗it) p , where u∗ and u∗it are the friction velocity and impact threshold friction velocity. The power p varies in the range of 0.7-1.8 on Mars and ∼1.5 on Earth, depending on the period and amplitude of the gusty inflow wind. Our results show that the law of Martian and terrestrial transport rate are not universal, and hence one should be cautious when trying to extrapolate existing terrestrial results to Mars.

  15. Microbial mats in playa lakes and other saline habitats: Early Mars analog?

    Science.gov (United States)

    Bauld, John

    1989-01-01

    Microbial mats are cohesive benthic microbial communities which inhabit various Terra (Earth-based) environments including the marine littoral and both permanent and ephemeral (playa) saline lakes. Certain geomorphological features of Mars, such as the Margaritifer Sinus, were interpreted as ancient, dried playa lakes, presumably formed before or during the transition to the present Mars climate. Studies of modern Terran examples suggest that microbial mats on early Mars would have had the capacity to survive and propagate under environmental constraints that would have included irregularly fluctuating regimes of water activity and high ultraviolet flux. Assuming that such microbial communities did indeed inhabit early Mars, their detection during the Mars Rover Sample Return (MRSR) mission depends upon the presence of features diagnostic of the prior existence of these communities or their component microbes or, as an aid to choosing suitable landing, local exploration or sampling sites, geomorphological, sedimentological or chemical features characteristic of their playa lake habitats. Examination of modern Terran playas (e.g., the Lake Eyre basin) shows that these features span several orders of magnitude in size. While stromatolites are commonly centimeter-meter scale features, bioherms or fields of individuals may extend to larger scales. Preservation of organic matter (mats and microbes) would be favored in topographic lows such as channels or ponds of high salinity, particularly those receiving silica-rich groundwaters. These areas are likely to be located near former zones of groundwater emergence and/or where flood channels entered the paleo-playa. Fossil playa systems which may aid in assessing the applicability of this particular Mars analog include the Cambrian Observatory Hill Beds of the Officer Basin and the Eocene Wilkins Peak Member of the Green River Formation.

  16. Mars - is it a habitable planet? - A biological approach to find answers to this question

    Science.gov (United States)

    de Vera, J. P.; Lorek, A.; Koncz, A.; Khan, A.; Schulze-Makuch, D.; Möhlmann, D.; Spohn, T.

    2012-12-01

    An overview on different experiments with photosynthetic organisms such as extremophilic microorganisms like lichens and cyanobacteria and even higher plants shows the different degrees of adaptation. The most resistant organisms can be found in tropic deserts and in polar and alpine habitats. The reason for their resistance can be explained by their occurrence in intensely irradiated, very dry and/or cold environments which are supposed to be as close as possible to Martian surface conditions. A systematically approach comparing measurements on photosynthetic activity of a variety of organisms in relation to measured environmental parameters obtained in Mars analog field sites with data collected from space exposed samples or during Mars simulation experiments will show differences and common results after analyzing the investigated organisms. Some of the investigated species were exposed during different experiments either directly to real space conditions on space exposure platforms like BIOPAN and EXPOSE-E on the International Space Station or to Mars simulation conditions in a Mars simulation chamber. Some of these species were also exposed to both of the extreme environmental conditions. In parallel environmental parameters were monitored in space and in the simulation chambers to get an impression about the influence of each of the tested parameters on metabolic activity. The outcome of this work might be relevant to classify e.g. Mars as a habitable planet by a new experimental and biological approach and to evaluate how bio-regenerative life supporting systems might be feasible and discuss the likelihood of terra forming Mars in the far future.

  17. Guidelines for 2007 MARS exercise

    CERN Multimedia

    HR Department

    2007-01-01

    Following the introduction of the new Merit Appraisal and Recognition Scheme (MARS), full details of the scheme are now available via the HR Department's homepage or directly on the Department's MARS web page: in English: http://humanresources.web.cern.ch/HumanResources/internal/personnel/pmd/cr/MARS.asp or French: http://humanresources.web.cern.ch/humanresources/internal/personnel/pmd/cr/mars_fr.asp You will find on this page: 'Introduction to MARS' with detailed information presented in Frequently Asked Questions; these include the MARS timetable for proposals and decisions; 'Regulations' with links to the scheme's statutory documents; 'Procedures and Forms' and 'Useful Information' with links to all the relevant documentation; these include the mandates of the Senior Staff Advisory Committee (SSAC) and the Technical Engineers and Administrative Careers Committee (TEACC). HR Department Tel. 73566

  18. Traceability of PDO Olive Oil “Terra di Bari” Using High Resolution Melting

    Directory of Open Access Journals (Sweden)

    Cinzia Montemurro

    2015-01-01

    Full Text Available The aim of the research was to verify the applicability of microsatellite (SSR markers in High Resolution Melting (HRM analysis for the identification of the olive cultivars used in the “Terra di Bari” PDO extra virgin olive oil. A panel of nine cultivars, widespread in Apulia region, was tested with seventeen SSR primer pairs and the PCR products were at first analysed with a Genetic Analyzer automatic sequencer. An identification key was obtained for the nine cultivars, which showed an unambiguous discrimination among the varieties constituting the “Terra di Bari” PDO extra virgin olive oil: Cima di Bitonto, Coratina, and Ogliarola. Subsequently, an SSR based method was set up with the DCA18 marker, coupled with HRM analysis for the distinction of the Terra di Bari olive oil from non-Terra di Bari olive oil using different mixtures. Thus, this analysis enabled the distinction and identification of the PDO mixtures. Hence, this assay provided a flexible, cost-effective, and closed-tube microsatellite genotyping method, well suited to varietal identification and authentication analysis in olive oil.

  19. Overcoming Terra Nullius: Aboriginal Perspectives in Schools as a Site of Philosophical Struggle.

    Science.gov (United States)

    Butler, Kathy

    2000-01-01

    Examines the philosophical basis of "Terra Nullius" as a justification for colonialism and racism directed at indigenous peoples, and its persistence as a pervasive mindset that impedes true equality and reconciliation in Australia. Discusses problems that arise when biased teachers or those with little cross-cultural experience attempt to present…

  20. Adjustments to the MODIS Terra Radiometric Calibration and Polarization Sensitivity in the 2010 Reprocessing

    Science.gov (United States)

    Meister, Gerhard; Franz, Bryan A.

    2011-01-01

    The Moderate-Resolution Imaging Spectroradiometer (MODIS) on NASA s Earth Observing System (EOS) satellite Terra provides global coverage of top-of-atmosphere (TOA) radiances that have been successfully used for terrestrial and atmospheric research. The MODIS Terra ocean color products, however, have been compromised by an inadequate radiometric calibration at the short wavelengths. The Ocean Biology Processing Group (OBPG) at NASA has derived radiometric corrections using ocean color products from the SeaWiFS sensor as truth fields. In the R2010.0 reprocessing, these corrections have been applied to the whole mission life span of 10 years. This paper presents the corrections to the radiometric gains and to the instrument polarization sensitivity, demonstrates the improvement to the Terra ocean color products, and discusses issues that need further investigation. Although the global averages of MODIS Terra ocean color products are now in excellent agreement with those of SeaWiFS and MODIS Aqua, and image quality has been significantly improved, the large corrections applied to the radiometric calibration and polarization sensitivity require additional caution when using the data.

  1. TERRA-KLEEN RESPONSE GROUP, INC. SOLVENT EXTRACTION TECHNOLOGY: INNOVATIVE TECHNOLOGY EVALUATION REPORT

    Science.gov (United States)

    This report summarizes the results of a field demonstration conducted under the SITE program. The technology which was demonstrated was a solvent extraction technology developed by Terra-Kleen Response Group. Inc. to remove organic contaminants from soil. The technology employs...

  2. FIELD EVALUATION OF TERRA THERM IN SITU THERMAL DESTRUCTION (ISTD) TREATMENT OF HEXACHLOROCYCLOPENTADIENE

    Science.gov (United States)

    This report summarizes the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) Program evaluation of the In Situ Thermal Destruction (ISTD) technology, developed by others, was refined by TerraTherm, Inc. The demonstration was designed to ...

  3. Terra Pretas: Charcoal Amendments Influence on Relict Soils and Modern Agriculture

    Science.gov (United States)

    Ricigliano, Kristin

    2011-01-01

    Most soils found in the Amazon region are characterized by highly weathered profiles that are incapable of longterm agricultural production. However, small patches of highly fertile relict soil referred to as Terra Pretas, are also found in the Amazon region, and have maintained their integrity for thousands of years. These soils were…

  4. Electronic-government in Saudi Arabia: A positive revolution in the peninsula

    CERN Document Server

    Al-Mushayt, Omar S; Haq, Kashiful

    2012-01-01

    The informatization practice of countries all over the world has shown that the level of a government's informatization is one main factor that can affect its international competitive power. At present, e-government construction is regarded as one of the most important tasks for the national economy and society upliftment and informatization in Saudi Arabia. Unlike the traditional governments, an e-government takes on a new look with its framework and operation mode more suitable for the contemporary era. In fact, it is a basic national strategy to promote Saudi Arabia's informatization by means of e-government construction. This talk firstly introduces the basic concepts and relevant viewpoints of egovernment, then reviews the development process of e-government in Saudi Arabia, and describes the current states, development strategies of e-government in Saudi Arabia. And also review e-government maturity models and synthesize them e-government maturity models are investigated, in which the authors have prop...

  5. 76 FR 7152 - ICT Trade Mission to Saudi Arabia; Application Deadline Extended

    Science.gov (United States)

    2011-02-09

    ... International Trade Administration ICT Trade Mission to Saudi Arabia; Application Deadline Extended AGENCY: International Trade Administration, Department of Commerce. ACTION: Notice. Timeframe for Recruitment and... Federal Register, posting on the Commerce Department trade mission calendar (...

  6. The Influence of Mineralogy on Recovering Organic Acids from Mars Analogue Materials Using the One-Pot Derivatization Experiment on the Sample Analysis at Mars(SAM) Instrument Suite

    Science.gov (United States)

    Stalport, Fabien; Glavin, Daniel P.; Eigenbrode, J. L.; Bish, D.; Blake, D.; Coll, P.; Szopa, C.; Buch, A.; McAdam, A.; Dworkin, J. P.; Mahaffy, P. R.

    2012-01-01

    The search for complex organic molecules on Mars, including important biomolecules such as amino acids and carboxylic acids, will require a chemical extraction and a derivatization step to transform these organic compounds into species that are sufficiently volatile to be detected by gas chromatography mass spectrometry (GCMS). We have developed a ''one-pot'' extraction and chemical derivatization protocol using N-methyl-N-(tert-butyldimethylsilyl) trifluoroacetamide (MTBSTFA) and dimethylformamide (DMF) for the Sample Analysis at Mars (SAM) experiment instrument suite on NASA's the Mars Science Laboratory (MSL) mission. The temperature and duration of the derivatization reaction, pre-concentration of chemical derivatives, and gas chromatographic separation parameters have been optimized under SAM instrument design constraints. MTBSTFA/DMF extraction and derivatization at 300 1C for several minutes of a variety of terrestrial Mars analog materials facilitated the detection of amino acids and carboxylic acids in a surface soil sample collected from the Atacama Desert and a carbonate-rich stromatolite sample from Svalbard. However, the rapid reaction of MTBSTFA with water in several analog materials that contained high abundances of hydrated minerals, and the possible deactivation of derivatized compounds by iron oxides, as detected by XRD/XRF using the CheMin field unit Terra, proved to be highly problematic for the direct extraction of organics using MTBSTFA. The combination of pyrolysis and two different wet-chemical derivatization methods employed by SAM should enable a wide range of organic compounds to be detected by GCMS if present on Mars.

  7. Review of Terra MODIS thermal emissive band L1B radiometric performance

    Science.gov (United States)

    Moeller, Chris; Menzel, W. P.; Quinn, Greg

    2014-09-01

    The MODerate-resolution Imaging Spectroradiometer (MODIS) on NASA's Earth Observing System Terra satellite, launched into orbit on 18 December 1999, will have a "first light" 15th anniversary on 24 February 2015. For nearly 15 years the MODIS instrument has provided radiances in all spectral bands. Though some detectors have fallen below SNR thresholds, the vast majority of spectral bands continue to provide high quality L1B measurements for use in L2 science algorithms supporting global climate research. Radiometric accuracy of the Terra MODIS thermal emissive bands (TEBs) in the C6 L1B product has been assessed using various approaches over the nearly 15 year Terra MODIS data record, including comparisons with instruments on the ground, in aircraft under-flights, and on other satellites. All of these approaches contribute to the understanding of the Terra MODIS radiometric L1B performance. Early in the lifetime of Terra, ground-based measurements and NASA ER-2 aircraft under-flights revealed that TEBs in the infrared window ("window" bands) are well calibrated and performing within accuracy specifications. The ER-2 under-flights also suggested that many atmospheric bands may be performing outside of specification, especially LWIR CO2 sensitive bands that are subject to optical crosstalk, although analysis uncertainties are larger for atmospheric bands. Beginning in 2007, MetOp-A IASI observations were used to evaluate Terra MODIS TEB performance through Simultaneous Nadir Overpass (SNO) comparisons. These inter-satellite comparisons largely affirm the early aircraft and ground-based evaluations, showing that all Terra MODIS window bands have small biases, minimal trending, and minor detector and mirror side striping over the 2007-2013 timeframe. Most atmospheric bands are performing satisfactorily near to specification; however, biases, striping and trending are large and significantly out of specification in the water vapor sensitive band 27 and ozone sensitive

  8. Mars Orbiting Plasma Surveyor (MOPS)

    OpenAIRE

    Barabash, Stas; André, Mats; Blomberg, Lars; Lundin, Rickard; Marklund, Göran; Rathsman, Peter; von Schéele, Fredrik; Wahlund, Jan-Erik

    2006-01-01

    Mars Orbiting Plasma Surveyor (MOPS) is a microsatellite mission focused on studies of the near -Mars environment and the planet - solar wind interaction. The recent findings by the ESA Mars Express mission further highlighted the complexity of the processes taking place at the planet resulting from the solar wind interaction that strongly affect the planet's atmosphere. However, despite many previous Martian missions carrying different types of space plasma experiments, a comprehensive inves...

  9. A Conceptual Framework for the Promotion of Trusted Online Retailing Environment in Saudi Arabia

    OpenAIRE

    Rayed AlGhamdi; Steve Drew; Thamer Alhussain

    2012-01-01

    This paper presents a model conceptual framework that is aimed at promoting trust in the online retailingenvironment in the Kingdom of Saudi Arabia (KSA). Despite rapid Internet growth, the development of onlineretailing in Saudi Arabia continues to progress very slowly compared to that of the developed and leadingdeveloping countries. To determine the reason behind the sluggish growth of online retailing in the KSA, amixed methods study involving retailers and customers was conducted in four...

  10. Motivation for domestic tourism : a case study of the Kingdom of Saudi Arabia

    OpenAIRE

    Bogari, Naima Bakor

    2002-01-01

    In Saudi Arabia there is a growing amount of leisure time and a high percentage of disposable income is being spent on various forms of tourism; such trends have increased the number of Saudis travelling to tourist destinations, internationally or domestically. Spending the annual holiday away from Saudi is normal for most Saudi families and it is estimated that the total expenditure on domestic tourism in Saudi Arabia is only 16.7% of total tourism expenditure. International e...

  11. Economic Efficiency Modelling of Water Resources in the Kingdom of Saudi Arabia

    OpenAIRE

    Bassam Hamdar; Hussin Hejase; Tamar Sayed

    2014-01-01

    Water is one of the most precious and valuable resources in the world generally and in Saudi Arabia specially. Situated in the tropical and sub-tropical desert region with arid climate, the Kingdom of Saudi Arabia (KSA) is exposed to dry winds and limited water resources .Therefore, the scarcity of fresh water resources poses a major challenge and affects the Saudi development plans since they realized that their supply of freshwater cannot be taken for granted. Moreover, the demand for fresh...

  12. The driving factors of continuance online shopping: Gender differences in behaviour the case of Saudi Arabia

    OpenAIRE

    Al-maghrabi, T; Dennis, C.

    2009-01-01

    This study proposes a revised technology acceptance model that integrates expectation confirmation theory to measure gender differences with regard to continuance online shopping intentions in Saudi Arabia. The 465-respondent sample consists of 68.8% women and 31.4% men. A structural equation model confirms model fit. Perceived usefulness, enjoyment, and subjective norms are determinants of online shopping continuance in Saudi Arabia. Both male and female groups are equivalent....

  13. The driving factors of continuance online shopping: Gender differences in behaviour among students in Saudi Arabia

    OpenAIRE

    Al-maghrabi, T; Dennis, C.

    2009-01-01

    This study proposes a revised technology acceptance model that integrates expectation confirmation theory to measure student gender differences with regard to continuance online shopping intentions in Saudi Arabia. The 234-respondent sample consists of 61.5% women and 38.5% men. A structural equation model confirms model fit. Perceived usefulness, enjoyment, and subjective norms are determinants of online shopping continuance in Saudi Arabia. Both male and female groups are equivalent. Th...

  14. Epidemiological aspects of prematurity in the Eastern region of Saudi Arabia

    OpenAIRE

    Al-Qurashi, Faisal O.; Abdullah A Yousef; Awary, Bassam H.

    2016-01-01

    Objectives: To assess the epidemiological characteristics of prematurity and survival rate in preterm infants diagnosed at a university hospital in the Eastern province of Saudi Arabia. Methods: A retrospective study was carried out of 476 preterm infants who were admitted with the diagnosis of prematurity to King Fahd Hospital of the University, Al-Khobar, Saudi Arabia, between June 2008 and 2013. Demographics, birth weight, and neonatal survival rate were analyzed. Results: Four hundred and...

  15. The factors driving online shopping in Saudi Arabia: Gender differences and behavior

    OpenAIRE

    Al-maghrabi, T; Dennis, C.

    2009-01-01

    Purpose — This study proposes a revised technology acceptance model that integrates expectation confirmation theory to measure gender differences with regard to continuance online shopping intentions in Saudi Arabia. Design/Methodology — The 465-respondent sample consists of 68.8% women and 31.4% men. A structural equation model confirms model fit. Findings — Perceived usefulness, enjoyment, and subjective norms are determinants of online shopping continuance in Saudi Arabia. Both male...

  16. A SOCIO-CULTURAL OVERVIEW OF E-LEARNING IN SAUDI ARABIA

    OpenAIRE

    Yamin, Mohammad

    2015-01-01

    Many regard Saudi Arabia as a conservative and religious nation with a perception of some degree of neglect or discrimination towards its female population. This deters many to realize the kind of revolution this nation is going through, especially in the field of education. Many might not realize that the kingdom of Saudi Arabia has state of art educational institutions with best possible equipment and infrastructure in the world. In addition, the government is providing very lucrative schol...

  17. The prevalence of sexual dysfunction in the female health care providers in Jeddah, Saudi Arabia

    OpenAIRE

    Rouzi, Abdulrahim A; Nora Sahly; Dana Sawan; Souzan Kafy; Faten Alzaban

    2015-01-01

    The objective of this study was to determine the prevalence of sexual dysfunction in Saudi and non-Saudi female health care providers in Jeddah, Saudi Arabia. One -hundred twenty (60 Saudi and 60 non-Saudi) sexually active female health care professionals in Jeddah, Saudi Arabia, were anonymously surveyed using the English version of the female sexual function index questionnaire. The individual domain scores for pain, arousal, lubrication, orgasm, satisfaction, pain, and overall score for th...

  18. Gender-segregated Education in Saudi Arabia: Its Impact on Social Norms the Saudi Labor Market

    OpenAIRE

    Roula Baki

    2004-01-01

    This article examines the Kingdom of Saudi Arabia's gender-segregated higher education system and how it is used to transmit the Kingdom's traditional societal expectations to the employment sector. With Saudi Arabia's current need for economic change, the education system is retarding instead of accelerating reform. A background consisting of Saudi Arabian history, governing laws, religious beliefs and women's roles is examined. I then discuss the education system's preservation goal by cons...

  19. Screening for Chlamydia trachomatis infection among infertile women in Saudi Arabia

    OpenAIRE

    Kamel RM

    2013-01-01

    Remah M Kamel Department of Obstetrics and Gynecology, Faculty of Medicine, University of Jazan, Saudi Arabia Background: Chlamydia trachomatis infection is a worldwide-distributed sexually transmitted infection that may lead to infertility. Objectives: This study aims to report the prevalence of Chlamydia trachomatis infection among infertile women in Saudi Arabia. Patients and methods: A community-based study carried out at the obstetrics and gynecology clinic at Jazan General Hospital, Sa...

  20. Prevalence and characteristics of abnormal Papanicolaou smear in Central Saudi Arabia

    OpenAIRE

    Al-Kadri, Hanan M.; Kamal, Mehak; Bamuhair, Samira S.; Omair, Aamir A.; Bamefleh, Hana S.

    2015-01-01

    Objectives: To assess the prevalence and characteristics of abnormal pap smear in the central region of Saudi Arabia. Methods: In this retrospective case control study conducted in the Departments of Obstetrics and Gynecology, and Histopathology at King Abdulaziz Medical City, Riyadh, Kingdom of Saudi Arabia, all pap smears screened for Saudi women between 2008 and 2011 were reviewed. Approximately 5000 pap smears are screened annually at King Abdulaziz Medical City utilizing the Bethesda III...

  1. The first national public breast cancer screening program in Saudi Arabia

    OpenAIRE

    Abulkhair, Omalkhair A.; Al Tahan, Fatina M.; Young, Susan E.; Musaad, Salma MA.; Jazieh, Abdul-Rahman M.

    2010-01-01

    BACKGROUND AND OBJECTIVES: Despite its relatively low incidence in Saudi Arabia, breast cancer has been the most common cancer among Saudi females for the past 12 consecutive years. The objective of this study was to report the results of the first national public breast cancer screening program in Saudi Arabia. METHODS: Women 40 years of age or older underwent breast cancer screening. Mammograms were scored using the Breast Imaging-Reporting and Data System (BI-RADS). Correlations between im...

  2. Body mass index and obstetric outcomes in Saudi Arabia: a prospective cohort study

    OpenAIRE

    El-Gilany, Abdel-Hady; Hammad, Sabry

    2010-01-01

    BACKGROUND AND OBJECTIVES: We examined the effect of body mass index in early pregnancy on pregnancy outcome since no study in Saudi Arabia has addressed this question. METHODS: This prospective cohort study involved women registered for antenatal care during the first month of pregnancy at primary health care centers in Al-Hassa, Saudi Arabia. Data was collected from records and by direct interview. RESULTS: The study included 787 women. Compared to normal weight women (n=307), overweight (n...

  3. The factors driving online shopping in Saudi Arabia: Regional and behavioral differences among women

    OpenAIRE

    Al-maghrabi, T; Dennis, C.

    2009-01-01

    This study proposes a revised technology acceptance model that integrates expectation confirmation theory to measure regional differences with regard to continuance online shopping intentions in Saudi Arabia. The sample consists of 650 female respondents. A structural equation model confirms model fit. Perceived usefulness, enjoyment, and subjective norms are determinants of online shopping continuance in Saudi Arabia. Women in the eastern, western, and central region groups are equivalent. T...

  4. Bioassay- and liquid chromatography/mass spectrometry-guided acetylcholinesterase inhibitors from Picriafel-terrae

    Directory of Open Access Journals (Sweden)

    Lu Wen

    2013-01-01

    Full Text Available Background: Picria fel-terrae is a traditional Chinese medicine. Materials and Methods: A new approach to the search for acetylcholinesterase (AChE inhibitors from Picria fel-terrae is presented. Results: Bioassay- and LC-MS-guided fractionation of the ethyl acetate extract was from traditional Chinese medicine P.fel-terrae. Following primary extraction, the ethyl acetate extracts fraction of P.fel-terrae showed strong AChE inhibitory activities. So the sample was separated using highperformance liquid chromatography (HPLC. The effluent was split towards two identical 96-well fraction collectors, and the presence of the biologically interesting portion and chromatographic fractions could be readily detected by analyzing selected ion chromatograms through an electrophoresis-electrospray ionization mass spectrometry (ESIMS system for accurate mass measurement. One 96-well plate was used for a bioassay (AChE-inhibitory assay and detected the bioactivity and position of the relevant peak in the chromatogram. The positive well in the second 96-well plate was used for identification by LC-(+ ESIMS. Conclusion: As abovementioned, the AChE inhibitory constituents from P.fel-terrae by LC-bioassay-ESIMS were rapid identified. Liquid chromatography/ mass spectrometry (LC-MS screening detected the presence of six active compounds, identified as picfeltarraenin IA (1, picfeltarraenin IB (2, picfeltarraenin IV (3, picfeltarraenin X (4, picfeltarraenin XI (5, and one unknown compound. The structures were further determined by 13C NMR. The six compounds expressed stronger AChE inhibition than the known AChE inhibitorTacrine. Above all, the value of this LC-bioassay-ESIMS methodology is highlighted by the finding and structure elucidation of the active constituents from many other structural families of natural products.

  5. Kingdom of Saudi Arabia Geospatial Information Infrastructure - AN Initial Study

    Science.gov (United States)

    Alsultan, S. H.; Rahman, A. A.

    2015-10-01

    This paper reviews the current Geographic Information System (Longley et al.) implementation and status in the Kingdom of Saudi Arabia (KSA). Based on the review, several problems were identified and discussed. The characteristic of these problems show that the country needs a national geospatial centre. As a new initiative for a national geospatial centre, a study is being conducted especially on best practice from other countries, availability of national committee for standards and policies on data sharing, and the best proposed organization structure inside the administration for the KSA. The study also covers the degree of readiness and awareness among the main GIS stakeholders within the country as well as private parties. At the end of this paper, strategic steps for the national geospatial management centre were proposed as the initial output of the study.

  6. Retinal vein occlusion in Saudi Arabia: possible role of dehydration.

    Science.gov (United States)

    Alghadyan, A A

    1993-10-01

    The medical records of 90 patients with a clinical diagnosis of retinal vein occlusion (RVO) who were seen at two referral hospitals in Saudi Arabia were reviewed. Sixty-eight (75.6%) were men. Central RVO was present in 50 patients (55.6%); branch RVO, in 35 patients (38.9%); and hemiretinal occlusion, in five patients (5.6%). Arterial hypertension was present in 43 patients (47.8%); diabetes mellitus, in 28 patients (31%); and preexisting glaucoma, in 26 patients (28.9%). The date of onset of RVO was available in 61 patients. Eighteen attacks (29.5%) had occurred during the month of Ramadan. The Student's t test of paired samples indicated that the incidence of RVO during the month of Ramadan was significantly higher than that of the other months of the Gregorian year. These findings suggest that dehydration may play a role in the pathogenesis of RVO. PMID:8304694

  7. The Challenges Faced by New Science Teachers in Saudi Arabia

    Science.gov (United States)

    Alsharari, Salman

    Growing demand for science teachers in the Kingdom of Saudi Arabia, fed by increasing numbers of public school students, is forcing the Saudi government to attract, recruit and retain well-qualified science teachers. Beginning science teachers enter the educational profession with a massive fullfilment and satisfaction in their roles and positions as teachers to educating children in a science classroom. Nevertheless, teachers, over their early years of practice, encounter numerous challenges to provide the most effective science instruction. Therefore, the current study was aimed to identify academic and behavioral classroom challenges faced by science teachers in their first three years of teaching in the Kingdom of Saudi Arabia. In addition, new science teacher gender, school level and years of teaching experience differences in perceptions of the challenges that they encountered at work were analyzed. The present study also investigated various types of support that new science teachers may need to overcome academic and behavioral classroom challenges. In order to gain insights about ways to adequately support novice science teachers, it was important to examine new science teachers' beliefs, ideas and perceptions about effective science teaching. Three survey questionnaires were developed and distributed to teachers of both sexes who have been teaching science subjects, for less than three years, to elementary, middle and high school students in Al Jouf public schools. A total of 49 novice science teachers responded to the survey and 9 of them agreed to participate voluntarily in a face-to-face interview. Different statistical procedures and multiple qualitative methodologies were used to analyze the collected data. Findings suggested that the top three academic challenges faced by new science teachers were: poor quality of teacher preparation programs, absence of appropriate school equipment and facilities and lack of classroom materials and instructional

  8. Measuring Students' Beliefs about Physics in Saudi Arabia

    Science.gov (United States)

    Alhadlaq, H.; Alshaya, F.; Alabdulkareem, S.; Perkins, K. K.; Adams, W. K.; Wieman, C. E.

    2009-11-01

    Over the last decade, science education researchers in the US have studied students' beliefs about science and learning science and measured how these beliefs change in response to classroom instruction in science. In this paper, we present an Arabic version of the Colorado Learning Attitudes about Science Survey (CLASS) which was developed to measure students' beliefs about physics at King Saud University (KSU) in Riyadh, Saudi Arabia. We describe the translation process, which included review by four experts in physics and science education and ten student interviews to ensure that the statements remained valid after translation. We have administered the Arabic CLASS to over 300 students in introductory physics courses at KSU's men's and women's campuses. We present a summary of students' beliefs about physics at KSU and compare these results to similar students in the US.

  9. TERRA Expression Levels Do Not Correlate With Telomere Length and Radiation Sensitivity in Human Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Alexandra eSmirnova

    2013-05-01

    Full Text Available Mammalian telomeres are transcribed into long non-coding telomeric RNA molecules (TERRA that seem to play a role in the maintenance of telomere stability. In human cells, CpG island promoters drive TERRA transcription and are regulated by methylation. It was suggested that the amount of TERRA may be related to telomere length. To test this hypothesis we measured telomere length and TERRA levels in single clones isolated from five human cell lines: HeLa (cervical carcinoma, BRC-230 (breast cancer, AKG and GK2 (gastric cancers and GM847 (SV40 immortalized skin fibroblasts. We observed great clonal heterogeneity both in TRF (Terminal Restriction Fragment length and in TERRA levels. However, these two parameters did not correlate with each other. Moreover, cell survival to γ-rays did not show a significant variation among the clones, suggesting that, in this cellular system, the intra-population variability in telomere length and TERRA levels does not influence sensitivity to ionizing radiation. This conclusion was supported by the observation that in a cell line in which telomeres were greatly elongated by the ectopic expression of telomerase, TERRA expression levels and radiation sensitivity were similar to the parental HeLa cell line.

  10. Undergraduate teaching of forensic medicine in Saudi Arabia.

    Science.gov (United States)

    Madadin, Mohammed; Al-Saif, Dalia M; Khamis, Amar Hassan; Taha, Attia Z; Kharoshah, Magdy A; Alsayyah, Ahmed; Alfehaid, Suha; Yaghmour, Khalid; Hakami, Ahmad Yahia; Bamousa, Manal S; Menezes, Ritesh G; Almadani, Osama M

    2016-07-01

    Medico-legal tasks are not exclusive to forensic medical experts -any physician may face medico-legal issues in his career. Hence, the practice of medicine requires education in legal issues. In Saudi Arabia, there are 30 universities with medical colleges, but we do not know how they teach undergraduate forensic medicine and medico-legal issues. The aim of this study was to discover undergraduate training courses in forensic medicine in Saudi universities. We conducted a cross-sectional study involving all colleges of medicine in Saudi Arabia. A structured, self-administered questionnaire containing 13 items relating to the undergraduate forensic medicine course was distributed. Out of a total of 30 universities, 27 universities responded. Of these 27 universities, 16 (59.26%) teach forensic medicine to undergraduate medical students, and 11 (40.74%) do not teach forensic medicine in their undergraduate curriculum. Of the 27 universities that responded, none has a department of forensic medicine. Eleven universities that do not teach forensic medicine have no forensic medicine unit/division or faculty at all. Forensic medicine belongs to the pathology department in 11 universities, while it belongs to different departments in five universities. There is variation in teaching methods, years where the course is taught and length of the course. Practical and morgue visits take place in 7/16 (43.8%) universities, while 9/16 (56.3%) universities only teach the theoretical aspects of forensic medicine. All 16 universities teach forensic medicine only to medical students and do not teach it to students in other colleges such as dentistry and nursing. PMID:27354384

  11. Centro de Conferencias, Hotel y Mezquita Riyadh - Arabia Saudita

    Directory of Open Access Journals (Sweden)

    Dannatt, Trevor

    1980-11-01

    Full Text Available The complex, designed and built for the Finance Ministry of the Kingdom of Saudi Arabia, is located on a 78,000 m2 lot, close to the intersection of highways crossing the Arabian desert, which connect the location directly with the area of public buildings of the city and with the airport as well. The complex situates the Convention Hall, with 23,230 m2 of constructed surface, in the southeast half of the lot; the Hotel, with 14,860 m2 of constructed surface, Is on the other half. Each has independent accesses, as is the case of the Mosque which is located at one end of the lot. Individual dwellings three-storeys high, gardens, parking areas, service roads an auxiliary buildings have been constructed next to the Mosque.

    El conjunto, diseñado y construido para el Ministerio de Finanzas del Reino de Arabia Saudita, está situado en una parcela de 78.000 m2, próxima a la intersección de carreteras que cruzan el desierto arábigo y que conectan directamente la parcela con el área de edificios públicos de la ciudad y con el aeropuerto. El complejo sitúa en la mitad sudoeste el Centro de Conferencias, de 23.230 m2 de edificabilidad, y el Hotel, de 14.860 m2 de superficie construida, en la otra mitad; cada uno de ellos con accesos independientes, al igual que la Mezquita emplazada en un extremo de la parcela. Junto a ésta se han construido viviendas unifamiliares de tres plantas, así como jardines, aparcamientos, carreteras de servicio y locales auxiliares.

  12. Undergraduate teaching of forensic medicine in Saudi Arabia.

    Science.gov (United States)

    Madadin, Mohammed; Al-Saif, Dalia M; Khamis, Amar Hassan; Taha, Attia Z; Kharoshah, Magdy A; Alsayyah, Ahmed; Alfehaid, Suha; Yaghmour, Khalid; Hakami, Ahmad Yahia; Bamousa, Manal S; Menezes, Ritesh G; Almadani, Osama M

    2016-07-01

    Medico-legal tasks are not exclusive to forensic medical experts -any physician may face medico-legal issues in his career. Hence, the practice of medicine requires education in legal issues. In Saudi Arabia, there are 30 universities with medical colleges, but we do not know how they teach undergraduate forensic medicine and medico-legal issues. The aim of this study was to discover undergraduate training courses in forensic medicine in Saudi universities. We conducted a cross-sectional study involving all colleges of medicine in Saudi Arabia. A structured, self-administered questionnaire containing 13 items relating to the undergraduate forensic medicine course was distributed. Out of a total of 30 universities, 27 universities responded. Of these 27 universities, 16 (59.26%) teach forensic medicine to undergraduate medical students, and 11 (40.74%) do not teach forensic medicine in their undergraduate curriculum. Of the 27 universities that responded, none has a department of forensic medicine. Eleven universities that do not teach forensic medicine have no forensic medicine unit/division or faculty at all. Forensic medicine belongs to the pathology department in 11 universities, while it belongs to different departments in five universities. There is variation in teaching methods, years where the course is taught and length of the course. Practical and morgue visits take place in 7/16 (43.8%) universities, while 9/16 (56.3%) universities only teach the theoretical aspects of forensic medicine. All 16 universities teach forensic medicine only to medical students and do not teach it to students in other colleges such as dentistry and nursing.

  13. Drowning in children: Aseer Central Hospital experience, Southwestern Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Suliman H Al-Fifi

    2011-01-01

    Full Text Available Aim: To study the reasons, magnitude and outcome of drowning following submersion in water of children admitted to the Pediatric Intensive Care Unit in Aseer Province, Saudi Arabia. Materials and Methods: A retrospective cohort study of all pediatric patients (0-13 years old who drowned and were admitted to the Pediatric Intensive Care Unit, Aseer Central Hospital, Southwestern Saudi Arabia, between January 1st 1999 and December 31st 2009. Results: A total of 19 cases were admitted following submersion in water. The mean age was 5.2 years ±3.8. Majority of victims (94.1% were from the highland areas. Events most frequently occurred in the summer (46.7%, followed by spring and winter, 33.3% and 20%, respectively. Home events constituted 44.4% of submersion cases. Of these, 55.6% drowned in a washing container, While 53.4% submersed in swimming pools. Twenty-two percent of these accidents occurred in the sea and in wells while 11.1% occurred in a lake. The mean duration of submersion was 4.04 minutes ± 5.35. Cardiac arrest was reported upon arrival at hospital in 42.1% of the victims. There were seven deaths (36.8 % and in one patient (5.2 % there was severe brain injury. In all deceased cases, no adults were watching the children when the accidents occurred. Conclusion: Drowning is a significant risk factor facing our children and can claim lives. The media as well as the authority should play a major role in increasing the public awareness to minimize or prevent such a problem.

  14. Aerosols physical properties at Hada Al Sham, western Saudi Arabia

    Science.gov (United States)

    Lihavainen, H.; Alghamdi, M. A.; Hyvärinen, A.-P.; Hussein, T.; Aaltonen, V.; Abdelmaksoud, A. S.; Al-Jeelani, H.; Almazroui, M.; Almehmadi, F. M.; Al Zawad, F. M.; Hakala, J.; Khoder, M.; Neitola, K.; Petäjä, T.; Shabbaj, I. I.; Hämeri, K.

    2016-06-01

    This is the first time to clearly derive the comprehensive physical properties of aerosols at a rural background area in Saudi Arabia. Aerosol measurements station was established at a rural background area in the Western Saudi Arabia to study the aerosol properties. This study gives overview of the aerosol physical properties (PM10, PM2.5, black carbon and total number concentration) over the measurement period from November 2012 to February 2015. The average PM10 and PM2.5 concentrations were 95 ± 78 μg m-3 (mean ± STD, at ambient conditions) and 33 ± 68 μg m-3 (at ambient conditions), respectively. As expected PM10 concentration was dominated by coarse mode particles (PM10-PM2.5), most probably desert dust. Especially from February to June the coarse mode concentrations were high because of dust storm season. Aerosol mass concentrations had clear diurnal cycle. Lower values were observed around noon. This behavior is caused by wind direction and speed, during night time very calm easterly winds are dominating whereas during daytime the stronger westerly winds are dominating (sea breeze). During the day time the boundary layer is evolving, causing enhanced mixing and dilution leading to lower concentration. PM10 and PM2.5 concentrations were comparable to values measured at close by city of Jeddah. Black carbon concentration was about 2% and 6% of PM10 and PM2.5 mass, respectively. Total number concentration was dominated by frequent new particle formation and particle growth events. The typical diurnal cycle in particle total number concentration was clearly different from PM10 and PM2.5.

  15. Analysis of Organic Molecules Extracted from Mars Analogues and Influence of Their Mineralogy Using N-Methyl-N-(tert-butyldimethylsilyl)Trifluoroacetamide Derivatization Coupled with Gas Chromatography Mass Spectrometry in Preparation for the Sample Analysis at Mars Derivatization Experiment on the Mars Science Laboratory Mission

    Science.gov (United States)

    Stalport, F.; Glavin, D. P.; Eigenbrode, J. L.; Bish, D.; Blake, D.; Coll, P.; Szopa, C.; Buch, A.; McAdam, A.; Dworkin, J. P.; Mahaffy, P. R.

    2012-01-01

    The search for complex organic molecules on Mars, including important biomolecules such as amino acids and carboxylic acids will require a chemical extraction and derivatization step to transform these organic compounds into species that are sufficiently volatile to be detected by gas chromatography mass spectrometry (GCMS). We have developed, a one-pot extraction and chemical derivatization protocol using N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) and dimethylformamide (DMF) for the Sample Analysis at Mars (SAM) experiment on the Mars Science Laboratory (MSL). The temperature and duration the derivatization reaction, pre-concentration of chemical derivatives, and gas chromatographic separation parameters have been optimized under SAM instrument design constraints. MTBSTFA/DMF extraction and derivatization at 300 C for several minutes of a variety of terrestrial Mars analogue materials facilitated the detection of amino acids and carboxylic acids in a surface soil sample collected from the Atacama Desert and a carbonate-rich stromatolite sample from Svalbard. However, the rapid reaction of MTBSTFA with water in several analogue materials that contained high abundances of hydrated minerals and the possible deactivation of derivatized compounds by iron oxides, as detected by XRD/XRF using the CheMin field unit Terra, proved to be highly problematic for the direct extraction of organics using MTBSTFA, The combination of pyrolysis and two different chemical derivatization methods employed by SAM should enable a wide range of organic compounds to be detected by GCMS if present on Mars,

  16. Method of Relating Grain Size Distribution to Hydraulic Conductivity in Dune Sands to Assist in Assessing Managed Aquifer Recharge Projects: Wadi Khulays Dune Field, Western Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Oliver M. Lopez

    2015-11-01

    Full Text Available Planning for use of a dune field aquifer for managed aquifer recharge (MAR requires that hydraulic properties need to be estimated over a large geographic area. Saturated hydraulic conductivity of dune sands is commonly estimated from grain size distribution data by employing some type of empirical equation. Over 50 samples from the Wadi Khulays dune field in Western Saudi Arabia were collected and the grain size distribution, porosity, and hydraulic conductivity were measured. An evaluation of 20 existing empirical equations showed a generally high degree of error in the predicted compared to the measured hydraulic conductivity values of these samples. Statistical analyses comparing estimated versus measured hydraulic conductivity demonstrated that there is a significant relationship between hydraulic conductivity and mud percentage (and skewness. The modified Beyer equation, which showed a generally low prediction error, was modified by adding a second term fitting parameter related to the mud concentration based on 25 of the 50 samples analyzed. An inverse optimization process was conducted to quantify the fitting parameter and a new empirical equation was developed. This equation was tested against the remaining 25 samples analyzed and produced an estimated saturated hydraulic conductivity with the lowest error of any empirical equation. This methodology can be used for large dune field hydraulic conductivity estimation and reduce planning costs for MAR systems.

  17. Method of Relating Grain Size Distribution to Hydraulic Conductivity in Dune Sands to Assist in Assessing Managed Aquifer Recharge Projects: Wadi Khulays Dune Field, Western Saudi Arabia

    KAUST Repository

    Lopez, Oliver

    2015-11-12

    Planning for use of a dune field aquifer for managed aquifer recharge (MAR) requires that hydraulic properties need to be estimated over a large geographic area. Saturated hydraulic conductivity of dune sands is commonly estimated from grain size distribution data by employing some type of empirical equation. Over 50 samples from the Wadi Khulays dune field in Western Saudi Arabia were collected and the grain size distribution, porosity, and hydraulic conductivity were measured. An evaluation of 20 existing empirical equations showed a generally high degree of error in the predicted compared to the measured hydraulic conductivity values of these samples. Statistical analyses comparing estimated versus measured hydraulic conductivity demonstrated that there is a significant relationship between hydraulic conductivity and mud percentage (and skewness). The modified Beyer equation, which showed a generally low prediction error, was modified by adding a second term fitting parameter related to the mud concentration based on 25 of the 50 samples analyzed. An inverse optimization process was conducted to quantify the fitting parameter and a new empirical equation was developed. This equation was tested against the remaining 25 samples analyzed and produced an estimated saturated hydraulic conductivity with the lowest error of any empirical equation. This methodology can be used for large dune field hydraulic conductivity estimation and reduce planning costs for MAR systems.

  18. Toward an objective assessment of technical skills: a national survey of surgical program directors in Saudi Arabia

    OpenAIRE

    Alkhayal A; Aldhukair S; Alselaim N; Aldekhayel S; Alhabdan S; Altaweel W; Magzoub ME; Zamakhshary M

    2012-01-01

    Abdullah Alkhayal,1 Shahla Aldhukair,2 Nahar Alselaim,1 Salah Aldekhayel,1 Sultan Alhabdan,1 Waleed Altaweel,3 Mohi Elden Magzoub,4 Mohammed Zamakhshary1,21Department of Surgery, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia; 2Public Health Section, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia; 3Urology Department, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; 4Department of Medical Education, King Saud b...

  19. Mission from Mars:

    DEFF Research Database (Denmark)

    Dindler, Christian; Eriksson, Eva; Iversen, Ole Sejer;

    2005-01-01

    In this paper a particular design method is propagated as a supplement to existing descriptive approaches to current practice studies especially suitable for gathering requirements for the design of children's technology. The Mission from Mars method was applied during the design of an electronic...... school bag (eBag). The three-hour collaborative session provides a first-hand insight into children's practice in a fun and intriguing way. The method is proposed as a supplement to existing descriptive design methods for interaction design and children....

  20. Mars Rover RTG Study

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1989-08-25

    This report summarizes the results of a Radioisotope Thermoelectric Generator (RTG) design study conducted by Fairchild Space Company at the direction of the U.S. Department of Energy's Office of SpecialApplications, in suppport of the Mars Rover and Sample Return mission under investigation at NASA's Jet Propulsion Laboratory. The report is a rearranged, updated, and significantly expanded amalgam of three interrelated papers presented at the 24th Intersocity Energy Conversion Engineering Conference (IECEC) at Arlington, Virginia, on August 10, 1989.

  1. MARS15 overview

    Energy Technology Data Exchange (ETDEWEB)

    Mokhov, N.V.; Striganov, S.I.; /Fermilab

    2007-01-01

    MARS15 is a Monte Carlo code for inclusive and exclusive simulation of three-dimensional hadronic and electromagnetic cascades, muon, heavy-ion, and low-energy neutron transport in accelerator, detector, spacecraft, and shielding components in the energy range from a fraction of an electronvolt up to 100 TeV. Main features of the code are described in this paper with a focus on recent developments and benchmarking. Newest developments concern inclusive and exclusive nuclear event generators, extended particle list in both modes, heavy-ion capability, electromagnetic interactions, enhanced geometry, tracking, histogramming and residual dose modules, improved graphical-user interface, and other external interfaces.

  2. Life sciences and Mars exploration

    Science.gov (United States)

    Sulzman, Frank M.; Rummel, John D.; Leveton, Lauren B.; Teeter, Ron

    1990-01-01

    The major life science considerations for Mars exploration missions are discussed. Radiation protection and countermeasures for zero gravity are discussed. Considerations of crew psychological health considerations and life support systems are addressed. Scientific opportunities presented by manned Mars missions are examined.

  3. Mars oxygen production system design

    Science.gov (United States)

    Cotton, Charles E.; Pillow, Linda K.; Perkinson, Robert C.; Brownlie, R. P.; Chwalowski, P.; Carmona, M. F.; Coopersmith, J. P.; Goff, J. C.; Harvey, L. L.; Kovacs, L. A.

    1989-01-01

    The design and construction phase is summarized of the Mars oxygen demonstration project. The basic hardware required to produce oxygen from simulated Mars atmosphere was assembled and tested. Some design problems still remain with the sample collection and storage system. In addition, design and development of computer compatible data acquisition and control instrumentation is ongoing.

  4. Water and Life on Mars

    Science.gov (United States)

    McKay, Christopher P.; DeVincenzi, Donald (Technical Monitor)

    2000-01-01

    Mars appears to be cold dry and dead world. However there is good evidence that early in its history it had liquid water, more active volcanism, and a thicker atmosphere. Mars had this earth-like environment over three and a half billion years ago, during the same time that life appeared on Earth. The main question in the exploration of Mars then is the search for a independent origin of life on that planet. Ecosystems in cold, dry locations on Earth - such as the Antarctic - provide examples of how life on Mars might have survived and where to look for fossils. Although the Viking results may indicate that Mars has no life today, there is direct geomorphological evidence that, in the past, Mars had large amounts of liquid water on its surface - possibly due to a thicker atmosphere. From a biological perspective the existence of liquid water, by itself motivates the question of the origin of life on Mars. One of the martian meteorites dates back to this early period and may contain evidence consistent with life. From studies of the Earth's earliest biosphere we know that by 3.5 Gyr. ago, life had originated on Earth and reached a fair degree of biological sophistication. Surface activity and erosion on Earth make it difficult to trace the history of life before the 3.5 Gyr timeframe. Ecosystems in cold, dry locations on Earth - such as the Antarctic - provide examples of how life on Mars might have survived and where to look for fossils.

  5. Monitoring Mars for Electrostatic Disturbances

    Science.gov (United States)

    Compton, D.

    2011-01-01

    The DSN radio telescope DSS-13 was used to monitor Mars for electrostatic discharges from 17 February to 11 April, 2010, and from 19 April to 4 May, 2011, over a total of 72 sessions. Of these sessions, few showed noteworthy results and no outstanding electrostatic disturbances were observed on Mars from analyzing the kurtosis of radio emission from Mars. Electrostatic discharges on mars were originally detected in June of 2006 by Ruf et al. using DSS-13. he kurtosis (normalized fourth moment of the electrical field strength) is sensitive to non-thermal radiation. Two frequencies bands, either 2.4 and 8.4 GHz or 8.4 and 32 GHz were used. The non-thermal radiation spectrum should have peaks at the lowest three modes of the theoretical Schumann Resonances of Mars. The telescope was pointed away from Mars every 5 minutes for 45 seconds to confirm if Mars was indeed the sources of any events. It was shown that by including a down-link signal in one channel and by observing when the kurtosis changed as the telescope was pointed away from the source that the procedure can monitor Mars without the need of extra equipment monitoring a control source.

  6. Mars Express 10 years at Mars: Observations by the Mars Express Radio Science Experiment (MaRS)

    Science.gov (United States)

    Pätzold, M.; Häusler, B.; Tyler, G. L.; Andert, T.; Asmar, S. W.; Bird, M. K.; Dehant, V.; Hinson, D. P.; Rosenblatt, P.; Simpson, R. A.; Tellmann, S.; Withers, P.; Beuthe, M.; Efimov, A. I.; Hahn, M.; Kahan, D.; Le Maistre, S.; Oschlisniok, J.; Peter, K.; Remus, S.

    2016-08-01

    The Mars Express spacecraft is operating in Mars orbit since early 2004. The Mars Express Radio Science Experiment (MaRS) employs the spacecraft and ground station radio systems (i) to conduct radio occultations of the atmosphere and ionosphere to obtain vertical profiles of temperature, pressure, neutral number densities and electron density, (ii) to conduct bistatic radar experiments to obtain information on the dielectric and scattering properties of the surface, (iii) to investigate the structure and variation of the crust and lithosphere in selected target areas, (iv) to determine the mass, bulk and internal structure of the moon Phobos, and (v) to track the MEX radio signals during superior solar conjunction to study the morphology of coronal mass ejections (CMEs). Here we report observations, results and discoveries made in the Mars environment between 2004 and 2014 over almost an entire solar cycle.

  7. Safety during MARS exercise

    CERN Multimedia

    2015-01-01

    It is MARS(1) time again! All employed members of the CERN personnel are currently undergoing the annual MARS evaluations.   This is also a good occasion for supervisors and their supervisees to fill in or update the OHS-0-0-3 form(2) “Identification of occupational hazards”. Filling in the OHS-0-0-3 form is an opportunity to assess any safety issues related to the supervisee's activities.  Each of us should, together with our supervisor, regularly identify and assess the hazards we may be exposed to in the course of our professional activities and reflect on how to control and mitigate them. When filling in the OHS form for the first time, it is important to determine any potential hazards as well as the corresponding preventive measures, in particular training and protective equipment. When updating the form, please review the available information to ensure that it still corresponds to the current activities. The form should be updated w...

  8. Mars Exploration Rover mission

    Science.gov (United States)

    Crisp, Joy A.; Adler, Mark; Matijevic, Jacob R.; Squyres, Steven W.; Arvidson, Raymond E.; Kass, David M.

    2003-10-01

    In January 2004 the Mars Exploration Rover mission will land two rovers at two different landing sites that show possible evidence for past liquid-water activity. The spacecraft design is based on the Mars Pathfinder configuration for cruise and entry, descent, and landing. Each of the identical rovers is equipped with a science payload of two remote-sensing instruments that will view the surrounding terrain from the top of a mast, a robotic arm that can place three instruments and a rock abrasion tool on selected rock and soil samples, and several onboard magnets and calibration targets. Engineering sensors and components useful for science investigations include stereo navigation cameras, stereo hazard cameras in front and rear, wheel motors, wheel motor current and voltage, the wheels themselves for digging, gyros, accelerometers, and reference solar cell readings. Mission operations will allow commanding of the rover each Martian day, or sol, on the basis of the previous sol's data. Over a 90-sol mission lifetime, the rovers are expected to drive hundreds of meters while carrying out field geology investigations, exploration, and atmospheric characterization. The data products will be delivered to the Planetary Data System as integrated batch archives.

  9. Estimated Radiation Dosage on Mars

    Science.gov (United States)

    2002-01-01

    This global map of Mars shows the estimated radiation dosages from cosmic rays reaching the surface, a serious health concern for any future human exploration of the planet.The estimates are based on cosmic-radiation measurements by the Mars radiation environment experiment, an instrument on NASA's Mars 2000 Odyssey spacecraft, plus information about Mars' surface elevations from the laser altimeter instrument on NASA's Mars Global Surveyor. The areas of Mars expected to have the lowest levels of cosmic radiation are where the elevation is lowest, because those areas have more atmosphere above them to block out some of the radiation. Earth's thick atmosphere shields us from most cosmic radiation, but Mars has a much thinner atmosphere than we have on Earth.The colors in the map refer to the estimated annual dose equivalent in rems, a unit of radiation dose. The range is generally from 10 rems(color-coded dark blue) to 20 rems (color coded dark red). Radiation exposure for astronauts on the International Space Station in Earth orbit is typically equivalent to an annualized rate of 20 to 40 rems.NASA's Jet Propulsion Laboratory, Pasadena, Calif. manages the 2001 Mars Odyssey and Mars Global Surveyor missions for NASA's Office of Space Science, Washington D.C. The Mars radiation environment experiment was developed by NASA's Johnson Space Center, Houston. Lockheed Martin Astronautics, Denver, is the prime contractor for Odyssey, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  10. MODIS/TERRA MOD11B1 Land Surface Temperature and Emissivity Daily L3 Global 5 km Grid SIN

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The MODIS/Terra Land Surface Temperature and Emissivity (LST/E) products provide per-pixel temperature and emissivity values in a sequence of swath-based to...

  11. MODIS/TERRA MOD11_L2 Land Surface Temperature and Emissivity 5-Minute L2 Swath 1 km

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The MODIS/Terra Land Surface Temperature and Emissivity (LST/E) products provide per-pixel temperature and emissivity values in a sequence of swath-based to...

  12. Terra Cucersita = Терра Кукерсита / Annely Oone

    Index Scriptorium Estoniae

    Oone, Annely

    2012-01-01

    Projektist "Ümber TERRA CUCERSITA (Põlevkivimaa)", mille eesmärk on noorte seas huvi äratamine loodus- ja täppisteaduste ja tehnoloogia ning teadus- ja arendustegevuse vastu nende kompleksse populariseerimisprogrammi kaudu

  13. EASE-Grid 2.0 Land Cover Classifications Derived from Boston University MODIS/Terra Land Cover Data

    Data.gov (United States)

    National Aeronautics and Space Administration — These data provide land cover classifications derived from the Boston University MOD12Q1 V004 MODIS/Terra 1 km Land Cover Product (Friedl et al. 2002). The data are...

  14. MODIS/TERRA MOD11A2 Land Surface Temperature & Emissivity 8-Day L3 Global 1km

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The MODIS/Terra Land Surface Temperature and Emissivity (LST/E) products provide per-pixel temperature and emissivity values in a sequence of swath-based to...

  15. EASE-Grid Land-Ocean-Coastline-Ice Masks Derived from Boston University MODIS/Terra Land Cover Data

    Data.gov (United States)

    National Aeronautics and Space Administration — These Land-Ocean-Coastline-Ice (LOCI) files provide land classification masks derived from the Boston University MOD12Q1 V004 MODIS/Terra 1 km Land Cover Product...

  16. Comparisons of Terra- and Aqua MODIS in band reflectance and vegetation index%Terra MODIS和Aqua MODIS波段反射率及植被指数比较

    Institute of Scientific and Technical Information of China (English)

    王静; 郭铌

    2008-01-01

    Terra MODIS和Aqua MODIS之间单波段反射率及植被指数进行了比较.结果表明:Terra MODIS和Aqua MODIS单波段反射率及植被指数具有极显著的相关性,植被指数较单波段反射率相关性更高些;Terra MODIS单波段反射率值普遍较Aqua MODIS值低,而植被指数值普遍较Aqua MODIS值高;不同时段Terra MODIS和Aqua MODIS单波段反射率及植被指数间差异不同,植被指数在冬季差异最大,而单波段反射率则在夏秋季差异较大;不同植被类型Terra MODIS和Aqua MODIS间植被指数差异总体规律相似,但单波段反射率间差异较为复杂;草甸、草原无论是单波段反射率还是植被指数,Terra MODIS和AquaMODIS的差异均比其他几种植被类型小,而阔叶林和一年两熟作物则差异相对大些.

  17. Martian clouds observed by Mars Global Surveyor Mars Orbiter Camera

    OpenAIRE

    Wang, Huiqun; Ingersoll, Andrew P.

    2002-01-01

    We have made daily global maps that cover both polar and equatorial regions of Mars for Ls 135°–360° and 0°–111° using the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red and blue wide-angle swaths taken from May 1999 to January 2001. We study the seasonal distribution of condensate clouds and dust clouds during roughly 1 Martian year using these daily global maps. We present the development and decay of the tropical cloud belt and the polar hoods, the spatial and temporal distributi...

  18. CAP_USO: Um sistema especialista para determinação da capacidade de uso da terra

    OpenAIRE

    Monica Luri Giboshi; Luiz Henrique Antunes Rodrigues; Francisco Lombardi Neto

    1999-01-01

    O objetivo deste trabalho foi desenvolver um sistema especialista (CAP_USO) para determinar a capacidade de uso da terra, visando auxiliar e dar mais agilidade ao processo de tomada de decisão para o planejamento do uso da terra. O sistema foi desenvolvido utilizando um software conhecido como C Language Integrated Production System (CLIPS), desenvolvido pela National Aeronautics and Space Administration (Nasa). Para determinar a capacidade de uso, foram considerados doze fatores limitantes a...

  19. La gestione del movimento terra con i sistemi di controllo 3DMC di Topcon

    Directory of Open Access Journals (Sweden)

    Marco Pallotta

    2007-04-01

    Full Text Available La spinta dei fratelli Trovati verso l’innovazione è il comune denominatore che sta caratterizzando molte entità nel settore del movimento terra in questi anni. Costituita nel 1980 a Perugia dai titolari, Lamberto e Valeriano Trovati, nel corso degli anni l’azienda si è consolidata ed ha acquisito una buona posizione nel mercato, adattandosi alle mutevoli richieste della domanda mediante la fornitura di nuovi servizi, tra tutti l’edilizia stradale. I Trovati, che avevano precedentemente maturato esperienza nel movimento terra presso aziende operanti nel settore, si sono affidati alle tecnologie Topcon allo scopo di ottimizzare il lavoro in cantiere, incrementando la produttività e riducendo tempi morti e sprechi di materiale.

  20. Superstructure scattering distribution based ship recognition in TerraSAR-X imagery

    International Nuclear Information System (INIS)

    Benefiting from the improved resolution and polarization information of SAR data, ship recognition has attracted much attention during the last decade. This paper considers the ship recognition in TerraSAR-X imagery. We propose a novel feature extraction algorithm, named Superstructure Scattering Distribution (SSD), by investigating the ship's superstructure and corresponding electromagnetic scattering mechanism. In SSD, we first segment the image areas that correspond to the scattering of ship's superstructure using segmentation and edge detection methods. Once the superstructure areas of ship in SAR imagery have been obtained, we then calculate a novel feature parameter to describe the distribution and shape complexity of the ship based on the fractal dimension and other shape complexity descriptors. Extensive experiments have been carried out on ship datasets collected from TerraSAR-X SAR imagery. The results validate that the SSD feature can achieve better performance together with other physical features

  1. Estimation of Atmospheric Path Delays in TerraSAR-X Data using Models vs. Measurements

    Directory of Open Access Journals (Sweden)

    Donat Perler

    2008-12-01

    Full Text Available Spaceborne synthetic aperture radar (SAR measurements of the Earth’s surface depend on electromagnetic waves that are subject to atmospheric path delays, in turn affecting geolocation accuracy. The atmosphere influences radar signal propagation by modifying its velocity and direction, effects which can be modeled. We use TerraSAR-X (TSX data to investigate improvements in the knowledge of the scene geometry. To precisely estimate atmospheric path delays, we analyse the signal return of four corner reflectors with accurately surveyed positions (based on differential GPS, placed at different altitudes yet with nearly identical slant ranges to the sensor. The comparison of multiple measurements with path delay models under these geometric conditions also makes it possible to evaluate the corrections for the atmospheric path delay made by the TerraSAR processor and to propose possible improvements.

  2. Traffic monitoring with the German remote monitoring satellite TerraSAR-X; Verkehrsmonitoring mit dem deutschen Fernerkundungssatelliten TerraSAR-X

    Energy Technology Data Exchange (ETDEWEB)

    Runge, H. [DLR-Institut fuer Methodik Fernerkundung, Oberpfaffenhofen (Germany); Ruhe, M. [DLR-Institut fuer Verkehrsforschung, Berlin-Adlershof (Germany)

    2003-12-01

    The TerraSAR-X satellite will be started in early 2006 and will provide pictures with a spatial resolution of less than 1 m. This is the first civil satellite resulting from a 'Public Private Partnership' between DLR and satellite producer EADS Astrium GmbH. The partners will share the cost. EADS intends to market the satellite pictures on a commercial basis via their Astrium company subsidiary Infoterra, while the DLR intends to make them available to the scientific community. Traffic monitoring will be a new application of remote monitoring. (orig.) [German] Fuer Anfang 2006 ist der Start des ersten operationellen deutschen Fernerkundungssatelliten TerraSAR-X geplant. Dieser Radar-Satellit wird erstmals im zivilen Bereich Bilder der Erdoberflaeche mit einer raeumlichen Aufloesung von bis zu einem Meter liefern. Das Projekt wird als 'Public Private Partnership' durchgefuehrt, die zwischen dem DLR und dem Satellitenhersteller EADS Astrium GmbH geschlossen wurde. Beide Seiten finanzieren den Bau des Satelliten gemeinsam und teilen sich die Nutzung: Die EADS Astrium-Tochter Infoterra wird die Satellitenbilder kommerziell vermarkten, das DLR ist fuer die wissenschaftliche Nutzergemeinschaft zustaendig. Eine neue Anwendung der Fernerkundung wird dabei die Verkehrsbeobachtung sein. (orig.)

  3. Investigation and Mitigation of the Crosstalk Effect in Terra MODIS Band 30

    OpenAIRE

    Junqiang Sun; Sriharsha Madhavan; Menghua Wang

    2016-01-01

    It has been previously reported that thermal emissive bands (TEB) 27–29 in the Terra (T-) MODerate resolution Imaging Spectroradiometer (MODIS) have been significantly affected by electronic crosstalk. Successful linear theory of the electronic crosstalk effect was formulated, and it successfully characterized the effect via the use of lunar observations as viable inputs. In this paper, we report the successful characterization and mitigation of the electronic crosstalk for T-MODIS band 30 us...

  4. An Overview of Lunar Calibration and Characterization for the EOS Terra and Aqua MODIS

    Science.gov (United States)

    Xiong, X.; Salomonson, V. V.; Sun, J.; Chiang, K.; Xiong, S.; Humphries, S.; Barnes, W.; Guenther, B.

    2004-01-01

    The Moon can be used as a stable source for Earth-observing sensors on-orbit radiometric and spatial stability monitoring in the VIS and NIR spectral regions. It can also serve as a calibration transfer vehicle among multiple sensors. Nearly identical copies of the Moderate Resolution Imaging Spectroradiometer (MODE) have been operating on-board the NASA's Earth Observing System (EOS) Terra and Aqua satellites since their launches in December 1999 and May 2002, respectively. Terra and Aqua MODIS each make observations in 36 spectral bands covering the spectral range from 0.41 to 14.5 microns and are calibrated on-orbit by a set of on-board calibrations (OBCs) including: 1) a solar diffuser (SD), 2) a solar diffuser stability monitor (SDSM), 3) a blackbody (BB), and 4) a spectro-radiometric calibration assembly (SRCA). In addition to fully utilizing the OBCs, the Moon has been used extensively by both Terra and Aqua MODIS to support their on-orbit calibration and characterization. A 4 This paper provides an overview of applications of lunar calibration and characterization from the MODIS perspective, including monitoring radiometric calibration stability for the reflective solar bands (RSBs), tracking changes of the sensors response versus scan-angle (RVS), examining the sensors spatial performance , and characterizing optical leaks and electronic crosstalk among different spectral bands and detectors. On-orbit calibration consistency between the two MODIS instruments is also addressed. Based on the existing on-orbit time series of the Terra and Aqua MODIS lunar observations, the radiometric difference between the two sensors is less than +/-1% for the RSBs. This method provides a powerful means of performing calibration comparisons among Earth-observing sensors and assures consistent data and science products for the long-term studies of climate and environmental changes.

  5. Integrating regional and continental scale comparisons of tree composition in Amazonian terra firme forests

    OpenAIRE

    E. N. Honorio Coronado; Baker, T. R.; Phillips, O.L.; Pitman, N. C. A.; Pennington, R. T.; R. Vásquez Martínez; A. Monteagudo; H. Mogollón; N. Dávila Cardozo; M. Ríos; García-Villacorta, R.; Valderrama, E.; M. Ahuite; I. Huamantupa; Neill, D. A.

    2009-01-01

    We contrast regional and continental-scale comparisons of the floristic composition of terra firme forest in South Amazonia, using 55 plots across Amazonia and a subset of 30 plots from northern Peru and Ecuador. Firstly, we examine the floristic patterns using both genus- or species-level data and find that the species-level analysis more clearly distinguishes different plot clusters. Secondly, we compare the patterns and causes of floristic differences at regional and continental scales. At...

  6. Terra Preta Sanitation: A Key Component for Sustainability in the Urban Environment

    OpenAIRE

    Thorsten Schuetze; Vicente Santiago-Fandiño

    2014-01-01

    Terra Preta Sanitation (TPS) plays a key role in sustainable sanitation (SuSan) and in the sustainable management of resources such as water, energy, soil (agriculture), liquid and solid organic waste streams as well as in the development of sustainable urban environment and infrastructure systems. This paper discusses the advantages of, and requirements for, SuSan systems, focusing on TPS. Case studies showing the stepwise extension and re-development of conventional sanitation systems (CSS)...

  7. Coherent scatterers detection: application over glacier terrain using TerraSAR-X time series data

    OpenAIRE

    Sanjuan-Ferrer, Maria J.; Hajnsek, Irena; Papathanassiou, Kostantinos P.

    2011-01-01

    This paper investigates the detection of Coherent Scatterers (CSs) in ice and glacier terrain by means of TerraSAR-X time series data in the test site of the Helheim Glacier in Greenland. CSs are evaluated with respect to detection and potential applications. Applying optimized detection scheme can be useful for retrieving information about the glacier movement using time series data. Finally, some conclusions about the temporal stability of natural CSs are obtained by ...

  8. Long-term drift induced by the electronic crosstalk in Terra MODIS Band 29

    Science.gov (United States)

    Sun, Junqiang; Madhavan, Sriharsha; Xiong, Xiaoxiong; Wang, Menghua

    2015-10-01

    Terra MODerate Resolution Imaging Spectroradiometer (MODIS) is one of the key sensors in the NASA's Earth Observing System, which has successfully completed 15 years of on-orbit operation. Terra MODIS continues to collect valuable information of the Earth's energy radiation from visible to thermal infrared wavelengths. The instrument has been well characterized over its lifetime using onboard calibrators whose calibration references are traceable to the National Institute of Standards and Technology standards. In this paper, we focus on the electronic crosstalk effect of Terra MODIS band 29, a thermal emissive band (TEB) whose center wavelength is 8.55 µm. Previous works have established the mechanism to describe the effect of the electronic crosstalk in the TEB channels of Terra MODIS. This work utilizes the established methodology to apply to band 29. The electronic crosstalk is identified and characterized using the regularly scheduled lunar observations. The moon being a near-pulse-like source allowed easy detection of extraneous signals around the actual Moon surface. First, the crosstalk-transmitting bands are identified along with their amplitudes. The crosstalk effect then is characterized using a moving average mechanism that allows a high fidelity of the magnitude to be corrected. The lunar-based analysis unambiguously shows that the crosstalk contamination is becoming more severe in recent years and should be corrected in order to maintain calibration quality for the affected spectral bands. Finally, two radiometrically well-characterized sites, Pacific Ocean and Libya 1 desert, are used to assess the impact of crosstalk effect. It is shown that the crosstalk contamination induces a long-term upward drift of 1.5 K in band 29 brightness temperature of MODIS Collection 6 L1B, which could significantly impact the science products. The crosstalk effect also induces strong detector-to-detector differences, which result in severe stripping in the Earth view

  9. Estimation of Daily Sunshine Duration from Terra and Aqua MODIS Data

    OpenAIRE

    Kandirmaz, H. M.; K. Kaba

    2014-01-01

    Some studies have shown that the estimation of global sunshine duration can be done with the help of geostationary satellites because they can record several images of the same location in a day. In this paper, images obtained from the MODIS (Moderate Resolution Imaging Spectroradiometer) sensors of polar orbiting satellites Aqua and Terra were used to estimate daily global sunshine duration for any region in Turkey. A new quadratic correlation between daily mean cloud cover index and relati...

  10. Assessment of diverse algorithms applied on MODIS Aqua and Terra data over land surfaces in Europe

    OpenAIRE

    Glantz, P.; Tesche, M

    2012-01-01

    The aim of the present study is to validate AOT (aerosol optical thickness) and Ångström exponent (α), obtained with the SAER (Satellite AErosol Retrieval) algorithm for MODIS (MODerate resolution Imaging Spectroradiometer) Aqua and Terra calibrated level 1 data (1 km horizontal resolution at ground) and MODIS Collection 5 (c005) standard product retrievals (10 km), against AERONET (AErosol RObotic NETwork) observations over land surfaces in Europe. The three time periods investigated in ...

  11. Inter-comparison of Terra and Aqua MODIS Feflective Solar Bands using Suomi NPP VIIRS

    OpenAIRE

    Blonski, Slawomir; Cao, Changyong; Uprety, Sirish; Shao, Xi

    2013-01-01

    VIIRS (Visible Infrared Imager Radiometer Suite) onboard the Suomi NPP (National Polar-orbiting Partnership) satellite has been acquiring Earth observations for more than a year. During that time, SNO (Simultaneous Nadir Overpass) events have provided many opportunities for inter-comparisons between VIIRS and the MODIS (Moderate Resolution Imaging Spectroradiometer) instruments from the Aqua and Terra satellites. The SNOs have occurred over snow-covered Antarctica, which provided bright surfa...

  12. The Biotoxicity of Mars Soils

    Science.gov (United States)

    Kerney, Krystal

    2010-01-01

    Recent evidence from the Opportunity and Spirit rovers suggests that the soils on Mars might be very high in biotoxic materials induding sulfate salts, chlorides, and acidifying agents. Yet, very little is known about how the chemistries of Mars soils might affect the survival and growth of terrestrial microorganisms. The primary objectives of the proposed research will be to: (1) prepare and characterize Mars analog soils amended with potential biotoxic levels of sulfates, chlorides, and acidifying minerals; (2) use the stimulants to conduct a series of toxicology assays to determine if terrestrial microorganisms from spacecraft or extreme environments can survive direct exposure to the biotoxic soils, and (3) mix soils from extreme environments on Earth into Mars analog soils to determine if terrestrial microorganisms can grow and replicate under Martian conditions. The Mars analog soils will be thoroughly characterized by a wide diversity of soil chemistry assays to determine the exact nature of the soluble biotoxic components following hydration. The microbial experiments will be designed to test the effects of Mars stimulants on microbial survival, growth and replication during direct challenge experiments. Toxicology experiments will be designed to mimic terrestrial microbes coming into contact with biotoxic soils with and without liquid water. Results are expected to help" ... characterize the limits of life in ... planetary environments ... " and may help constrain the search for life on Mars.

  13. Mars Before the Space Age

    CERN Document Server

    Jones, Barrie W

    2008-01-01

    Mars has surely been scrutinised since the dawn of humankind. In the 16th century Tycho Brahe made accurate observations of the position of Mars that enabled Johannes Kepler to obtain his first two laws of planetary motion. In the 17th century the first telescope observations were made, but very little surface detail could be discerned. Throughout the 18th and 19th centuries telescopes improved, revealing many dark areas on the red tinted surface. After the close opposition of 1877 Giovanni Schiaparelli announced about 40 canali on Mars. This led to the saga of the canals of Mars, laid to rest in 1971 when Mariner 9 made observations from Martian orbit showing that the canali/canals of Mars do not exist. Belief that there was life on Mars was widespread in the 19th century, including the view that the dark areas were some form of plant life. This view persisted until Mariner 4 flew past Mars in 1965 and discovered a far thinner atmosphere than previously thought, with impact craters dominating the images. It ...

  14. Assessment of metals in cosmetics commonly used in Saudi Arabia.

    Science.gov (United States)

    Salama, Ahmed K

    2015-10-01

    Cosmetics are one of the most important sources of releasing heavy metals. Different varieties of chemicals are used in cosmetic products as ingredients and some are used as preservatives. There are concerns regarding the presence of harmful chemicals in these products. Among the harmful chemicals, cosmetic products contain heavy metals. The present study was conducted to determine the content of certain heavy metals in the products made in different countries and marketed in Saudi Arabia. Thirty-one products of different brands or misbrands of commonly used cosmetic products (hair cream, beauty cream, skin cream, hair food formula, hair gel, whitening daily scrub, shampoo, shower gel, body care, body lotion, hand wash, daily fairness, shaving cream, toothpaste, germ and beauty soap, and cream soap) were purchased from local markets of Saudi Arabia. Samples were analyzed to determine the concentrations of ten metals (lead, aluminum, cadmium, cobalt, chromium, copper, manganese, nickel, mercury, and arsenic) using inductively coupled plasma mass spectrometer (ICP-MS). Based on the maximum concentrations, the heavy metal contents were arranged in the following decreasing order: Al > Cu > Mn > Pb > Cr > Ni > Hg > Co > As > Cd in cream products, Al > Pb > Cu > Cr > Mn > Ni > Hg > As > Co > Cd in shampoo products, Al > Cu > Pb > Cr > Mn > Ni > As > Co > Hg > Cd in soap products, and Al > Cu > Mn > Pb > Cr > Co > Ni > Cd > As > Hg in toothpaste products. Since the metal concentrations may relate to specific brands, product type, color, or cost, industrialist would have to check the raw materials before they are gathered into the final products to track the source of these contaminants. PMID:27613289

  15. Assessment of metals in cosmetics commonly used in Saudi Arabia.

    Science.gov (United States)

    Salama, Ahmed K

    2015-10-01

    Cosmetics are one of the most important sources of releasing heavy metals. Different varieties of chemicals are used in cosmetic products as ingredients and some are used as preservatives. There are concerns regarding the presence of harmful chemicals in these products. Among the harmful chemicals, cosmetic products contain heavy metals. The present study was conducted to determine the content of certain heavy metals in the products made in different countries and marketed in Saudi Arabia. Thirty-one products of different brands or misbrands of commonly used cosmetic products (hair cream, beauty cream, skin cream, hair food formula, hair gel, whitening daily scrub, shampoo, shower gel, body care, body lotion, hand wash, daily fairness, shaving cream, toothpaste, germ and beauty soap, and cream soap) were purchased from local markets of Saudi Arabia. Samples were analyzed to determine the concentrations of ten metals (lead, aluminum, cadmium, cobalt, chromium, copper, manganese, nickel, mercury, and arsenic) using inductively coupled plasma mass spectrometer (ICP-MS). Based on the maximum concentrations, the heavy metal contents were arranged in the following decreasing order: Al > Cu > Mn > Pb > Cr > Ni > Hg > Co > As > Cd in cream products, Al > Pb > Cu > Cr > Mn > Ni > Hg > As > Co > Cd in shampoo products, Al > Cu > Pb > Cr > Mn > Ni > As > Co > Hg > Cd in soap products, and Al > Cu > Mn > Pb > Cr > Co > Ni > Cd > As > Hg in toothpaste products. Since the metal concentrations may relate to specific brands, product type, color, or cost, industrialist would have to check the raw materials before they are gathered into the final products to track the source of these contaminants.

  16. Orogenic plateau magmatism of the Arabia-Eurasia collision zone

    Science.gov (United States)

    Allen, M. B.; Neill, I.; Kheirkhah, M.; van Hunen, J.; Davidson, J. P.; Meliksetian, Kh.; Emami, M. H.

    2012-04-01

    Magmatism is a common feature of high plateaux created during continental collision, but the causes remain enigmatic. Here we study Pliocene-Quaternary volcanics from the active Arabia-Eurasia collision zone, to determine the chemistry of these rocks and their relations to faulting and deeper lithospheric structure. The great majority of the centres lie within the overriding Eurasian plate in Iran, eastern Turkey and Armenia , implying that mantle fertilised by pre-collision subduction processes plays a significant role in magma generation. The composition of the Pliocene-Quaternary centres is extremely variable, ranging from OIB-like alkali basalts, to intermediate types resembling mature continental arc lavas, to potassic and even ultrapotassic lavas. These centres are erupted across a mosaic of pre-Cenozoic suture zones and heterogeneous lithospheric blocks. The chemical diversity implies a range of partial melting conditions operating on lithospheric and perhaps sub-lithospheric sources. Published data show a thick (>200 km) lithospheric keel beneath the Arabia-Eurasia suture, thinning to near normal thicknesses (~120 km) across much of central and northern Iran. Thin mantle lithosphere under eastern Turkey (max. ~30 km) may relate to the region's juvenile, accretionary lithosphere. These variable thicknesses are constraints on the cause of the melting in each area, and the degree of variation suggests that no one mechanism applies across the plateau. Various melting models have been suggested. Break-off of the subducted Neo-Tethyan oceanic slab is supported by tomographic data, which may have permitted melting related to adiabatic ascent of hot asthenosphere under areas where the lithosphere is thin. This seems a less plausible mechanism where the lithosphere is at normal or greater than normal thickness. The same problem applies to postulated lower lithosphere delamination. Isolated pull-aparts may account for the location of some centres, but are not

  17. Small-scale volcanoes on Mars: distribution and types

    Science.gov (United States)

    Broz, Petr; Hauber, Ernst

    2015-04-01

    Volcanoes differ in sizes, as does the amount of magma which ascends to a planetary surface. On Earth, the size of volcanoes is anti-correlated with their frequency, i.e. small volcanoes are much more numerous than large ones. The most common terrestrial volcanoes are scoria cones (active over most (if not all) of its history, a similar distribution of volcano size might be expected. Martian small-scale volcanoes were not intensely studied for a long time due to a lack of high-resolution data enabling their proper identification; however their existence and basic characteristics were predicted on theoretical grounds. Streams of new high-resolution images now enable discovering and studying kilometer-size volcanoes with various shapes in unprecedented detail. Several types of small-scale volcanoes in various regions on Mars were recently described. Scoria cones provide a record of magmatic volatile content and have been identified in Tharsis (Ulysses Colles), on flanks of large volcanoes (e.g., Pavonis Mons), in the caldera of Ulysses Patera, in chaotic terrains or other large depressions (Hydraotes Colles, Coprates Chasma) and in the northern lowlands. Tuff rings and tuff cones, formed as a result of water-magma interaction, seem to be relatively rare on Mars and were only tentatively identified in three locations (Nepenthes/Amenthes region, Arena Colles and inside Lederberg crater), and alternative interpretations (mud volcanoes) seem possible. Other relatively rare volcanoes seem to be lava domes, reported only from two regions (Acracida Planitia and Terra Sirenum). On the other hand, small shields and rootless cones (which are not primary volcanic landforms) represent widely spread phenomena recognized in Tharsis and Elysium. Based on these new observations, the distribution of small volcanoes on Mars seems to be much more widespread than anticipated a decade ago. There are sometimes significant differences in the final morphologies between Martian hypothesized

  18. Thenature of marbled Terra Sigillata slips: a combined mu XRF and mu XRD investigation

    Energy Technology Data Exchange (ETDEWEB)

    Leon, Yoanna; Sciau, Philippe; Goudeau, Philippe; Tamura, Nobumichi; Webb, Sam; Mehta, Apurva

    2009-01-31

    In addition to the red terra sigillata production, the largest Gallic workshop (La Graufesenque) made a special type of terra sigillata, called 'marbled' by the archaeologists. Produced exclusively on this site, this pottery is characterized by a surface finish made of a mixture of yellow and red slips. Because the two slips are intimately mixed, it is difficult to obtain the precise composition of one of the two constituents without contamination by the other. In order to obtain very precise correlation at the appropriate scale between the color aspect and the element and mineralogical phase distributions in the slip, combined electron microprobe, x-ray micro spectroscopies and micro diffraction on cross sectional samples were performed. The aim is to discover how potters were able to produce this unique type of terra sigillata and especially this slip showing an intense yellow color. Results show that the yellow component of marbled sigillata was made from a titanium-rich clay preparation. The color is related to the formation of a pseudobrookite (TiFe2O5) phase in the yellow part of the slip, the main characteristics of that structure being considered nowadays as essential for the fabrication of stable yellow ceramic pigments. Its physical properties such as high refractive indices and a melting point higher than that of most silicates widely used as ceramic colorants are indeed determinant for this kind of applications. Finally, the red parts have a similar composition (elementary and mineralogical) to the one of standard red slip.

  19. TerraSAR-X Small Baseline interferometry of Popocatepetl volcano, Mexico.

    Science.gov (United States)

    de Zeeuw van Dalfsen, Elske; Walter, Thomas

    2013-04-01

    Popocatepetl is an active 5426 m high stratovolcano, with a steep-walled, 400 by 600 m wide crater. It is located 70 km southeast of Mexico city, and its activity potentially influences up to 25 million people. More than 15 major eruptions occurred in historic times, the last one in 1947. The year 2012 has been a highly active one, with numerous ash plumes in mid-April, and explosions during July-October. We have acquired TerraSAR-X images of Popocatepetl, and the surrounding area, using strip and spot mode, covering this period. We have created small baseline interferograms from TerraSAR-X strip mode images, using the Stanford Method for Persistent Scatterers (StaMPS) software. Of the resulting interferograms, several show medium to good coherence on the lower and upper flanks of the volcano and some are even coherent in the crater area. We further analysed the data that cover the time period from 27 march 2012 to 22 october 2012. During this time period the volcano has been very active, displaying on and off: gas and ash plumes, explosions injecting incandescent fragments up to 1 km from the crater and even ashfall in municipalities up to 50 km away. The short revisit time of TerraSAR-X of 11 days increases the chances of a coherent image during such active periods. We present the preliminary results from this unique data set.

  20. Biografias e movimentos de luta por terra em Pernambuco Biographies and land claim movements in Pernambuco

    Directory of Open Access Journals (Sweden)

    Marcelo C. Rosa

    2009-01-01

    Full Text Available Este artigo analisa a contribuição das chamadas "lutas por terra" para a produção de novas formas de significação social na região da Zona da Mata de Pernambuco. Por meio da análise de entrevistas com militantes dos diversos movimentos que organizam ocupações de terra na região, foi possível compreender que, além da posse de um pedaço de terra, tais organizações criam condições inéditas para a transformação dos seus líderes em figuras de destaque nas instâncias políticas dos pequenos municípios da região, contribuindo assim para a modificação das estruturas tradicionais de poder.This paper analyzes the contribution of so-called 'land struggles' in the creation of new forms of 'social meaning' in a sugar plantation region of the Brazilian Northeast. Analysis of interviews with militants from various movements coordinating land occupations in the region reveals that, as well as supporting rural people's access to land, these organizations enable their leaders to become prominent figures in local urban politics, thereby contributing to the modification of traditional power structures.

  1. A LUTA PELA TERRA ENTRE A CIDADE E O CAMPO UM OLHAR SOBRE PRESIDENTE PRUDENTE

    Directory of Open Access Journals (Sweden)

    João Vitor Ramos da Silva

    2012-01-01

    Full Text Available Este texto é fruto das ações de pesquisa que vêm sendo desenvolvidas por meio do projeto de iniciação científica, denominado “Significados da Reforma Agrária em bairros periféricos de Presidente Prudente (SP: uma tentativa de diálogo entre a luta pela terra e a Soberania Alimentar”, vigente a partir de fevereiro de 2011, com financiamento da Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP. Tem por objetivo apresentar alguns aspectos sobre a relevância da inserção de comunidades periurbanas da cidade de Presidente Prudente no processo de luta pela terra no Pontal do Paranapanema, protagonizado principalmente pelos movimentos socioterritoriais, em especial o MST. O eixo central de análise envolve uma interrelação entre o trabalho, a luta pela terra e la Soberania Alimentar, assim como uma tentativa de construção de uma abordagem ontológica a partir da centralidade do trabalho, que potencialmente contribui para que as dicotomias teoricamente construídas entre cidade e campo sejam superadas, visto que os sujeitos da pesquisa, produtores de espaços/espacialidades e territórios/territorialidades, constituem o foco principal, para além das fragmentações.

  2. Corrections to MODIS Terra Calibration and Polarization Trending Derived from Ocean Color Products

    Science.gov (United States)

    Meister, Gerhard; Eplee, Robert E.; Franz, Bryan A.

    2014-01-01

    Remotely sensed ocean color products require highly accurate top-of-atmosphere (TOA) radiances, on the order of 0.5% or better. Due to incidents both prelaunch and on-orbit, meeting this requirement has been a consistent problem for the MODIS instrument on the Terra satellite, especially in the later part of the mission. The NASA Ocean Biology Processing Group (OBPG) has developed an approach to correct the TOA radiances of MODIS Terra using spatially and temporally averaged ocean color products from other ocean color sensors (such as the SeaWiFS instrument on Orbview-2 or the MODIS instrument on the Aqua satellite). The latest results suggest that for MODIS Terra, both linear polarization parameters of the Mueller matrix are temporally evolving. A change to the functional form of the scan angle dependence improved the quality of the derived coefficients. Additionally, this paper demonstrates that simultaneously retrieving polarization and gain parameters improves the gain retrieval (versus retrieving the gain parameter only).

  3. The Unique Geomorphology and Physical Properties of the Vestalia Terra Plateau

    Science.gov (United States)

    Buczkowski, D.L.; Wyrick, D.Y.; Toplis, M.; Yingst, R. A.; Williams, D. A.; Garry, W. B.; Mest, S.; Kneissl, T.; Scully, J. E. C.; Nathues, A.; DeSanctis, M. C.; LeCorre, L.; Reddy, V.; Hoffmann, M.; Ammannito, E.; Frigeri, A.; Tosi, F.; Preusker, F.; Roatsch, T.; Raymond, C. A.; Jaumann, R.; Pieters, C. M.; Russell, C. T.

    2014-01-01

    We produced a geologic map of the Av-9 Numisia quadrangle of asteroid Vesta using Dawn spacecraft data to serve as a tool to understand the geologic relations of surface features in this region. These features include the plateau Vestalia Terra, a hill named Brumalia Tholus, and an unusual "dark ribbon" material crossing the majority of the map area. Stratigraphic relations suggest that Vestalia Terra is one of the oldest features on Vesta, despite a model crater age date similar to that of much of the surface of the asteroid. Cornelia, Numisia and Drusilla craters reveal bright and dark material in their walls, and both Cornelia and Numisia have smooth and pitted terrains on their floors suggestive of the release of volatiles during or shortly after the impacts that formed these craters. Cornelia, Fabia and Teia craters have extensive bright ejecta lobes. While diogenitic material has been identified in association with the bright Teia and Fabia ejecta, hydroxyl has been detected in the dark material within Cornelia, Numisia and Drusilla. Three large pit crater chains appear in the map area, with an orientation similar to the equatorial troughs that cut the majority of Vesta. Analysis of these features has led to several interpretations of the geological history of the region. Vestalia Terra appears to be mechanically stronger than the rest of Vesta. Brumalia Tholus may be the surface representation of a dike-fed laccolith. The dark ribbon feature is proposed to represent a long-runout ejecta flow from Drusilla crater.

  4. Divergent plate boundaries and crustal spreading on Venus: Evidence from Aphrodite Terra

    International Nuclear Information System (INIS)

    The modes of lithospheric heat transfer and the tectonic styles may differ between Earth and Venus, depending on how the high surface temperature (700 K = 430 C), dense and opaque atmosphere (approx. 10 MPa = 100 bars), lack of water oceans, and the other known ways in which Venus differs from Earth, influence basic lithospheric processes, thermal gradient, upper mantle temperature, thermal and chemical evolution, and convection. A fundamental question is whether the lithosphere of Venus is horizontally stable, like the other terrestrial planets, or is mobile like that on Earth. The variety of characteristics, their integrated relationships, and their predictable behavior throughout Western Aphrodite Terra are similar to those features known to occur in association with the terrestrial seafloor at spreading centers and divergent plate boundaries. It is concluded that Western Aphrodite Terra represents the site of crustal spreading centers and divergent plate boundaries. The extent of similar characteristics and processes elsewhere on Venus outside of the 13,000 km long Western and Eastern Aphrodite Terra rise is unknown at the present, but their presence in other areas of the equatorial highlands, suggested from recent analysis, may be tested with forthcoming Magellan data

  5. Mars - an escaping planet?

    CERN Document Server

    Dvorak, R

    2005-01-01

    The chaotic behaviour of the motion of the planets in our Solar System is well established. Numerical experiments with a modified Solar System consisting of a more massive Earth have shown, that for special values of an enlargement factor K around 5 the dynamical state of a truncated planetary system (excluding Mercury and the outer planets Uranus and Neptune) is highly chaotic. On the contrary for values of the mass of the Earth up to the mass of Saturn no irregular dynamical behaviour was observed. We extended our investigations to the complete planetary system and showed, that this chaotic window found before still exists. Tests in different 'Solar Systems' showed that only including Jupiter and Saturn with their actual masses together with a 'massive' Earth (between 4 and 6 times more massive) destabilize the orbit of Mars so that even escapes from the system are possible.

  6. Mars Under the Microscope

    Science.gov (United States)

    2004-01-01

    This magnified look at the martian soil near the Mars Exploration Rover Opportunity's landing site, Meridiani Planum, shows coarse grains sprinkled over a fine layer of sand. The image was captured by the rover's microscopic imager on the 10th day, or sol, of its mission. Scientists are intrigued by the spherical rocks, which can be formed by a variety of geologic processes, including cooling of molten lava droplets and accretion of concentric layers of material around a particle or 'seed.'The examined patch of soil is 3 centimeters (1.2 inches) across. The circular grain in the lower left corner is approximately 3 millimeters (.12 inches) across, or about the size of a sunflower seed.

  7. The Mars water cycle

    Science.gov (United States)

    Davies, D. W.

    1981-01-01

    A model has been developed to test the hypothesis that the observed seasonal and latitudinal distribution of water on Mars is controlled by the sublimation and condensation of surface ice deposits in the Arctic and Antarctic, and the meridional transport of water vapor. Besides reproducing the observed water vapor distribution, the model correctly reproduces the presence of a large permanent ice cap in the Arctic and not in the Antarctic. No permanent ice reservoirs are predicted in the temperate or equatorial zones. Wintertime ice deposits in the Arctic are shown to be the source of the large water vapor abundances observed in the Arctic summertime, and the moderate water vapor abundances in the northern temperate region. Model calculations suggest that a year without dust storms results in very little change in the water vapor distribution. The current water distribution appears to be the equilibrium distribution for present atmospheric conditions.

  8. Mars rover concept development

    Science.gov (United States)

    Mctamaney, Louis S.; Douglas, Barry D.; Harmon, Scott Y.

    1989-01-01

    A structured study effort to develop an extensive, innovative set of mobility and navigation concepts for a planetary exploration vehicle along with the concomitant value system and evaluation tools is presented. A further objective is to submit these concepts to a rigorous, structured evaluation process to derive the most promising candidate systems. To support the evaluation process, a three-layer computer model of the Martian surface was developed, based on the 1/64 deg Digital Elevation Model (DEM) of Mars. Local surface roughness based on measured Martian slope distribution and power spectral density was superimposed on the DEM, and rocks based on Moore's distribution model were added. To assess performance, selected concepts were modeled using DADS, and simulations were run with the vehicle traversing the Martian surface model, including one-meter-high vertical steps and one-meter-wide crevasses. The design details of three promising candidate systems are presented, along with the discussion of their evolution with some recommendations.

  9. Belly Dancing on Mars

    Science.gov (United States)

    2004-01-01

    This image shows a screenshot from the software used by engineers to drive the Mars Exploration Rover Spirit. The software simulates the rover's movements across the martian terrain, helping to plot a safe course for the rover. The virtual 3-D world around the rover is built from images taken by Spirit's stereo navigation cameras. Regions for which the rover has not yet acquired 3-D data are represented in beige. The red dart to the left shows a target destination for the rover. Red lines indicate the path the rover's wheels will follow to reach the target, and the blue line denotes the path of the rover's 'belly button,' as engineers like to call it.

  10. Geologic map of Mars

    Science.gov (United States)

    Tanaka, Kenneth L.; Skinner, James A.; Dohm, James M.; Irwin, Rossman P.; Kolb, Eric J.; Fortezzo, Corey M.; Platz, Thomas; Michael, Gregory G.; Hare, Trent M.

    2014-01-01

    This global geologic map of Mars, which records the distribution of geologic units and landforms on the planet's surface through time, is based on unprecedented variety, quality, and quantity of remotely sensed data acquired since the Viking Orbiters. These data have provided morphologic, topographic, spectral, thermophysical, radar sounding, and other observations for integration, analysis, and interpretation in support of geologic mapping. In particular, the precise topographic mapping now available has enabled consistent morphologic portrayal of the surface for global mapping (whereas previously used visual-range image bases were less effective, because they combined morphologic and albedo information and, locally, atmospheric haze). Also, thermal infrared image bases used for this map tended to be less affected by atmospheric haze and thus are reliable for analysis of surface morphology and texture at even higher resolution than the topographic products.

  11. Salt Weathering on Mars

    Science.gov (United States)

    Jagoutz, E.

    2006-12-01

    Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement, these rocks were fragmented and disassembled. Nests of angular rock fragments are marking the locations of preexisting larger rocks. Frequently it is possible to reconstruct larger rounded rocks from smaller angular fragments. In other cases transport after fragmentation obscured the relationship of the fragments. However, a strewn field of fragments is still reminiscent of the preexisting rock. Mechanical salt weathering could be a plausible explanation for the insitu fragmentation of larger rounded blocks into angular fragments. Impact or secondary air fall induced fragmentation produces very different patterns, as observed around impact crates on Earth. Salt weathering of rocks is a common process in terrestrial environments. Salt crystallization in capillaries causes fragmentation of rocks, irrespective of the process of salt transportation and concentration. On Earth significant salt weathering can be observed in different climatic environments: in the transition zone of alluvial aprons and salt playas in desserts and in dry valleys of Antarctica. In terrestrial semi-arid areas the salt is transported by salt solution, which is progressively concentrated by evaporation. In Antarctic dry valleys freeze-thaw cycles causes salt transportation and crystallization resulting in rock fragmentation. This salt induced process can lead to complete destruction of rocks and converts rocks to fine sand. The efficient breakdown of rocks is dominating the landscape in some dry valleys of the Earth but possibly also on Mars. (Malin, 1974

  12. Approach to Mars Field Geology

    Science.gov (United States)

    Muehlberger, William; Rice, James W.; Parker, Timothy; Lipps, Jere H.; Hoffman, Paul; Burchfiel, Clark; Brasier, Martin

    1998-01-01

    The goals of field study on Mars are nothing less than to understand the processes and history of the planet at whatever level of detail is necessary. A manned mission gives us an unprecedented opportunity to use the immense power of the human mind to comprehend Mars in extraordinary detail. To take advantage of this opportunity, it is important to examine how we should approach the field study of Mars. In this effort, we are guided by over 200 years of field exploration experience on Earth as well as six manned missions exploring the Moon.

  13. 30. Cardiovascular risk factors burden in Saudi Arabia: The africa middle east cardiovascular epidemiological (ace study

    Directory of Open Access Journals (Sweden)

    A. Ahmed

    2016-07-01

    Full Text Available Limited data exit on the epidemiology of cardiovascular risk factors in Saudi Arabia particularly in relation to the differences between local citizens and expatriates. The aim of this analysis is to describe the current prevalence of cardiovascular risk factors among patients attending general practice clinics in Saudi Arabia. In a cross- sectional epidemiological study, the presence of cardiovascular risk factors (hypertension, diabetes, dyslipidaemia, obesity, smoking, and abdominal obesity was evaluated in stable adult outpatients attending primary care clinics in Saudi Arabia. Groups comparison were made between local Saudi patients and expatriates. A total of 550 participant were enrolled form different clinics in Saudi Arabia (71% were male, mean age was 43 ± 10 years. Nearly half of the study cohort had more than two cardiovascular risk factors (49.6%. Dyslipidemia had the highest prevalence (68.4%. Furthermore, prevalence of hypertension (47.5% vs. 31.4%, dyslipidaemia (75.2% vs. 55.1% and abdominal obesity (63.9% vs. 52.2% were higher among expatriates compare to Saudis (p-value < 0.001. This analysis clearly shows that there is a high prevalence of cardiovascular risk factors prevalence in Saudi population. In addition, a significant proportion of patients with risk factors have poor overall control. Programmed community based screening is needed for all cardiovascular risk factors in Saudi Arabia. Increased awareness and improved primary care services may decrease incidence of coronary artery disease and improve overall quality of life.

  14. Too costly to matter: Economics of nuclear power for Saudi Arabia

    International Nuclear Information System (INIS)

    Saudi Arabia has ambitious plans for nuclear power. Given this context, this paper examines the economics of nuclear power and compares it to two other sources of electricity, natural gas and solar energy. It calculates the costs of electricity generation, water desalination and the opportunity cost associated with forgone oil and gas revenues. A sensitivity analysis is included to account for variations in important parameters within the comparative cost analysis. Our results suggest that for a large range of parameters, the economics of nuclear power are not favorable in comparison with natural gas, even if the currently low domestic natural gas prices in Saudi Arabia were to rise substantially. Further, electricity from solar plants has the potential to be cheaper than nuclear power within the next decade if the rapid decline in solar energy costs in the last decade continue, i.e., before the first planned nuclear power plant would be completed. However, unless the price of oil drops substantially below current values, it would be more economically optimal to export the oil than using it for generating electricity. - Highlights: • Future projections show nuclear power is not cost effective for Saudi Arabia. • A combination of solar and natural gas could largely meet future electricity demand. • There are multiple, non-economic, motivations for Saudi Arabia's nuclear program. • Saudi Arabia would economically benefit by not using oil for electricity generation

  15. A GPS Network Densification in Saudi Arabia in Support of Geophysical Investigations in the Region

    Science.gov (United States)

    Almuslmani, B.; Al-Motari, E.; Bingley, R. M.; Teferle, F. N.; Moore, T.

    2006-12-01

    Current investigations of the motions of the Arabian and its neighboring plates are primarily based on GPS measurements obtained in the surrounding areas of the Arabian plate, with few stations actually located on the Arabian plate itself in the Kingdom of Saudi Arabia. In order to advance the knowledge of the dynamics of the Arabian plate and its intra-plate deformations, the General Directorate of Military Survey (GDMS), through a collaboration with the Institute of Engineering Surveying and Space Geodesy (IESSG), densified the GPS network in Saudi Arabia, covering nearly two thirds of the tectonic plate. Since July 2002, a network of 32 GPS stations has been established at locations of the Saudi Arabia geodetic network. At all of these GPS stations a concrete pillar has been used as the monument and the locations have been selected in order to give the broadest distribution of observing sites. During 2005, 27 additional GPS stations in the Hejaz and Asser Mountains in the south-western part of Saudi Arabia, have been established, with the GDMS GPS network now comprising a total of 59 stations. In this presentation we will introduce the new GPS network in Saudi Arabia established by GDMS and will present the initial results from campaigns in March 2003 and March 2005. We show preliminary estimates of absolute and relative Arabian plate motions inferred from the GPS network and a detailed comparison of the results based on the Bernese GPS software versions 4.2 and 5.0.

  16. Female Leadership Capacity and Effectiveness: A Critical Analysis of the Literature on Higher Education in Saudi Arabia

    Science.gov (United States)

    Alomair, Miznah O.

    2015-01-01

    In light of the progressive changes occurring in Saudi Arabia, developing female leadership capacity and effectiveness in the country's higher education is vital. This literature review examines the scholarship and research on female leadership in higher education in Saudi Arabia, describes the major barriers for female leaders, and provides a…

  17. Magnetic activity at Mars - Mars Surface Magnetic Observatory

    DEFF Research Database (Denmark)

    Vennerstrøm, Susanne; Menvielle, M.; Merayo, José M.G.;

    2012-01-01

    We use the extensive database of magnetic observations from the Mars Global Surveyor to investigate magnetic disturbances in the Martian space environment statistically, both close to and far from crustal anomalies. We discuss the results in terms of possible ionospheric and magnetospheric currents...... a magnetic experiment at the martian surface, the Mars Surface Magnetic Observatory (MSMO) including the science objectives, science experiment requirements, instrument and basic operations. We find the experiment to be feasible within the constraints of proposed stationary landing platforms....

  18. The ballistic Mars hopper: An alternative Mars mobility concept

    OpenAIRE

    Sercel, J. C.; Blandino, J. J.; Wood, K. L.

    1987-01-01

    The ballistic Mars hopper is proposed as an alternative mobility concept for unmanned exploration of the martian surface. In the ballistic Mars hopper concept, oxygen and carbon monoxide produced from the martian atmosphere are used as propellants in a rocket propulsion system for an unmanned vehicle on suborbital trajectories between landing sights separated by distances of up to 1000 km. This mobility concept is seen as uniquely capable of allowing both intensive and extensive exploration o...

  19. An extremely high altitude plume seen at Mars morning terminator

    Science.gov (United States)

    Sanchez-Lavega, Agustin; Garcia-Muñoz, Antonio; Garcia-Melendo, Enrique; Perez-Hoyos, Santiago; Gomez-Forrellad, Josep M.; Pellier, Christophe; Delcroix, Marc; Lopez-Valverde, Miguel Angel; Gonzalez-Galindo, Francisco; Jaeschke, Wayne; Parker, Donald C.; Phillips, James H.; Peach, Damian

    2014-11-01

    We report the occurrence in March and April 2012 of two bright very high altitude plumes at the Martian terminator at 250 km or more above the surface, thus well into the ionosphere and bordering on the exosphere. They were located at about 195 deg West longitude and -45 deg latitude (at Terra Cimmeria) and lasted for about 10 days. The features showed day-to-day variability, and were seen at the morning terminator but not at the evening limb, which indicates rapid evolution in less than 10 hours and a cyclic behavior. Photometric measurements are used to explore two possible scenarios to explain their nature. If the phenomenon is due to suspended particles (dust, CO2 or H2O ice clouds) reflecting solar radiation, the mean size is about 0.1 microns with a nadir optical depth > 0.06. Alternatively, the plume could be auroral emission above a region with a strong magnetic anomaly and where aurora has previously been detected. Importantly, both explanations defy our current understanding of the Mars upper atmosphere.AcknowledgementsThis work was supported by the Spanish MINECO projects AYA2012-36666 with FEDER support, CONSOLIDER program ASTROMOL CSD2009-00038 and AYA2011-30613-CO2-1. Grupos Gobierno Vasco IT765-13 and UPV/EHU UFI11/55.

  20. A Top to Bottom Lithospheric Study of Africa and Arabia

    Energy Technology Data Exchange (ETDEWEB)

    Pasyanos, M

    2006-10-31

    We study the lithospheric structure of Africa, Arabia and adjacent oceanic regions with fundamental-mode surface waves over a wide period range. Including short period group velocities allows us to examine shallower features than previous studies of the whole continent. In the process, we have developed a crustal thickness map of Africa. Main features include crustal thickness increases under the West African, Congo, and Kalahari cratons. We find crustal thinning under Mesozoic and Cenozoic rifts, including the Benue Trough, Red Sea, and East, Central, and West African rift systems. Crustal shear wave velocities are generally faster in oceanic regions and cratons, and slower in more recent crust and in active and formerly active orogenic regions. Deeper structure, related to the thickness of cratons and modern rifting, is generally consistent with previous work. Under cratons we find thick lithosphere and fast upper mantle velocities, while under rifts we find thinned lithosphere and slower upper mantle velocities. There are no consistent effects in areas classified as hotspots, indicating that there seem to be numerous origins for these features. Finally, it appears that the African Superswell has had a significantly different impact in the north and the south, indicating specifics of the feature (temperature, time of influence, etc.) to be dissimilar between the two regions. Factoring in other information, it is likely that the southern portion has been active in the past, but that shallow activity is currently limited to the northern portion of the superswell.

  1. Tobacco Use among Health Care Workers in Southwestern Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Ahmed A. Mahfouz

    2013-01-01

    Full Text Available The present study targeted health care workers (HCWs in Governmental Hospitals and Primary Health Care Centers in Abha City, southwestern Saudi Arabia. An anonymous self-report questionnaire was used to assess tobacco use and the reasons for smoking. The present study included 736 HCWs. The overall prevalence of tobacco use amounted to 26.3% (14.8% current and 11.5% former users. In a binary logistic regression analysis, males were found significantly more prone to smoke compared to females (aOR = 3.081, 95% CI: 2.004–4.739. Similarly, parental history of tobacco use was found to be a significant risk factor (aOR = 1.540, 95% CI: 1.040–2.278. Among current users, 89.9% were interested in quitting and 66.1% tried before to quit. The prevalence of smoking among HCWs in the present study, besides being a public health problem, represents a potential barrier in involving this group as a first line for tobacco control. There is a need for a national intervention programme in the country in a tailored manner for HCWs to control tobacco use parallel to the running national program for public. These interventions should begin early in basic medical education and to be applied continually during one’s medical career.

  2. Assessment of Ambient Air Quality in Riyadh City, Saudi Arabia.

    Directory of Open Access Journals (Sweden)

    B. H. Alharbi

    2014-08-01

    Full Text Available Concentrations of airborne particulate matter with an aerodynamic diameter less than 10 µm (PM10 and five gaseous air pollutants (O3, CO, NO2, SO2 and H2S were measured over a period of approximately six years (October 1999-June 2004 at five air quality monitoring network stations of King Abulaziz City for Science and Technology (KACST in Riyadh city, Saudi Arabia. The main objective of this study is to evaluate the quality of ambient air in relation to its possible effects on human health in the urban area of Riyadh city using the U.S. Environmental Protection Agency (USEPA Air Quality Index (AQI and break down analysis of five criteria pollutants (O3, CO, NO2 and SO2 and PM10 and Hydrogen Sulphide (H2S. The concentrations of selected pollutants in ambient air has shown upward trends except for sulfur dioxide (SO2 and hydrogen sulfide (H2S, which exhibited decreasing trends over the time. Using the AQI based on a health perspective, a breakdown analysis was conducted. The results confirmed that 71% of the time Riyadh city air is of “Good” quality using the AQI and causes almost no health impacts on city inhabitants. The remaining 29% of more problematic air quality is caused by PM10 (74% and SO2 (~24%. The study has revealed that both ozone (O3 and carbon monoxide (CO have little contribution to Riyadh air pollution at 2% and 0.52%, respectively.

  3. Osteoarthritis of knees and obesity in Eastern Saudi Arabia

    International Nuclear Information System (INIS)

    Objective was to find out the prevalence and relation between osteoarthritis of knees and obesity in Al-Ahsa region, Kingdom of Saudi Arabia (KSA). The study included 243 male and female patients diagnosed with osteoarthritis of knees of knees in between June 2001 to March 2003. All patients were recruited from the Physical Therapy Department, King Fahd Hofuf Hospital, Hofuf, KSA. The clinical diagnosis was supported plain x-rays of knees, and of other joint if needed. The weight and height of all patients were taken using one standard weight and height scale, and body mass index was also calculated and recorded. More than 90.53% of the patients referred with osteoarthritis of knees were obese or overweight. The mean body weight of all patients was 84.61 kg and the mean weight was 1.59 meters. Osteoarthritis of the knees was more in obese female than male patients with a female to male ratio of 2.37:1. Obesity is a disease. The aim of all health professionals and others in the community should be directed to the prevention of this disease and its risk to develop multiple complications. (author)

  4. Prevalence of Glomerular Diseases: King Khalid University Hospital, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Mitwalli A

    2000-01-01

    Full Text Available To obtain a more recent and comprehensive insight into the prevalence of glomerular diseases in our patient population, medical records of 200 patients with biopsy proven glomerulonephritis (GN, between January 1994 and June 1999, at the King Khalid University Hospital, Riyadh, Saudi Arabia were analyzed. Primary glomerular disease was found to be the most prevalent, accounting for 63.5% of all glomerular diseases. Among primary glomerular diseases, focal and segmental glomerulosclerosis (FSGS was the most common histological lesion (34.6% and was associated with a high prevalence of hypertension (86.4%, nephrotic syndrome (68.18%, hematuria (63.6% and renal functional impairment (27.3%. Mesangioproliferative GN was the second most common lesion (25.1% followed by mesangiocapillary GN (15.7%, IgA nephropathy (10.2%, and minimal change disease (8.5%. Amongst secondary glomerular diseases, lupus nephritis was the most prevalent (24.5%. In conclusion, primary glomerular diseases constituted the commonest group encountered and the prevalence of FSGS was quite high with male sex and young adults predominating. FSGS was also associated with a high prevalence of end-stage renal disease. Further collaborative studies are necessary to explore the predisposing factors and associations of glomerular disease, especially FSGS.

  5. Automated management of radioactive sources in Saudi Arabia

    Science.gov (United States)

    Al-Kheliewi, Abdullah S.; Jamil, M. F.; Basar, M. R.; Tuwaili, W. R.

    2014-09-01

    For usage of radioactive substances, any facility has to register and take license from relevant authority of the country in which such facility is operating. In the Kingdom of Saudi Arabia (KSA), the authority for managing radioactive sources and providing licenses to organizations for its usage is the National Center of Radiation Protection (NCRP). This paper describes the system that automates registration and licensing process of the National Center of Radiation Protection. To provide 24×7 accesses to all the customers of NCRP, system is developed as web-based application that provide facility to online register, request license, renew license, check request status, view historical data and reports etc. and other features are provided as Electronic Services that would be accessible to users via internet. The system also was designed to streamline and optimize internal operations of NCRP besides providing ease of access to its customers by implementing a defined workflow through which every registration and license request will be routed. In addition to manual payment option, the system would also be integrated with SADAD (online payment system) that will avoid lengthy and cumbersome procedures associated with manual payment mechanism. Using SADAD payment option license fee could be paid through internet/ATM machine or branch of any designated bank, Payment will be instantly notified to NCRP hence delay in funds transfer and verification of invoice could be avoided, SADAD integration is discussed later in the document.

  6. E-Commerce in Saudi Arabia: adoption and perspectives

    Directory of Open Access Journals (Sweden)

    Sadiq Sait

    2004-11-01

    Full Text Available Among one of the most far-reaching influences of the Internet, especially from the perspective of business and market models, is the concept and application of eCommerce. Today, this erstwhile ‘experimental’ commerce model has become a standard platform for streamlining business flows and broadening product outreach. This is validated by the significant emphasis by a number of countries in developing robust eCommerce architectures tailored to suit their economical-social systems. An interesting case study in this perspective is the Kingdom of Saudi Arabia, especially given its emphasis on local, regional and religious traditions. Presently, with a tremendous growth rate in Internet connectivity, the Kingdom is actively moving towards large-scale adoption of eCommerce systems. In 2001, a two year project was initiated to study the present influence of Internet on social, educational and business systems within the Kingdom. One of the major aspects was the analysis of user responses collected over the two-year period through a number of surveys, which were designed based on two prominent behavioural models: Theory of Planned Behaviour and Roger’s Theory of Diffusion of Innovations. The consequent analysis of the results was supported and in some cases verified with linear regression models. This paper reports on the consequent findings, which identify factors that may significantly affect the adoption of eCommerce in the Kingdom.

  7. Groundwater Quality Assessment in Jazan Region, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Adel M. Alhababy

    2015-04-01

    Full Text Available Jazan province is an arid area, located at the southwestern part of Saudi Arabia along the Red Sea coast. Groundwater is the only resource of drinking water in this area; thus, its suitability for drinking and domestic uses is of public and scientific concern. In this study, groundwater samples were collected from 23 sites in Jazan area during fall 2014; measurements and analysis of water quality parameters including pH, total dissolved solids TDS, turbidity, hardness, alkalinity, ammonia, nitrite, nitrate, sulfate, calcium, magnesium, chloride, iron and fluoride were carried out with references to WHO and Gulf Standardization Organization GSO. TDS values exceeded the permissible limit of 600 mg/l in 30.4% of samples, total hardness values exceeded the permissible limits of 300 mg/l in 34.8% of samples, and nitrate concentration exceeded the permissible limit of 50 mg/l in only one sample. However, the concentrations of investigated parameters in the groundwater samples were within the permissible limits of WHO. Our results showed that the water quality of groundwater in Jazan area is acceptable and could be used safely for drinking and domestic purposes. However, a special attention should be paid to the concentration of TDS and nitrate in groundwater in future studies.

  8. Measurement of acoustical characteristics of mosques in Saudi Arabia

    Science.gov (United States)

    Abdou, Adel A.

    2003-03-01

    The study of mosque acoustics, with regard to acoustical characteristics, sound quality for speech intelligibility, and other applicable acoustic criteria, has been largely neglected. In this study a background as to why mosques are designed as they are and how mosque design is influenced by worship considerations is given. In the study the acoustical characteristics of typically constructed contemporary mosques in Saudi Arabia have been investigated, employing a well-known impulse response. Extensive field measurements were taken in 21 representative mosques of different sizes and architectural features in order to characterize their acoustical quality and to identify the impact of air conditioning, ceiling fans, and sound reinforcement systems on their acoustics. Objective room-acoustic indicators such as reverberation time (RT) and clarity (C50) were measured. Background noise (BN) was assessed with and without the operation of air conditioning and fans. The speech transmission index (STI) was also evaluated with and without the operation of existing sound reinforcement systems. The existence of acoustical deficiencies was confirmed and quantified. The study, in addition to describing mosque acoustics, compares design goals to results obtained in practice and suggests acoustical target values for mosque design. The results show that acoustical quality in the investigated mosques deviates from optimum conditions when unoccupied, but is much better in the occupied condition.

  9. Anthropometric predictors of dyslipidemia among adults in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Abdalla A Saeed

    2013-03-01

    Full Text Available Background: dyslipidemia and obesity are key independent modifiable risk factors for many non communicable chronic diseases. Patterns of association between these factors may help prevention and control. This study aims to assess the association between lipids profile and obesity among adults in Kingdom of Saudi Arabia and identify anthropometric predictors of dyslipidemia.Methods: data were collected and analyzed from a cross-sectional study using WHO STEPwise approach that included 4 990 Saudi adults aged 15- 64 years selected by stratified, multistage, cluster random sampling technique. Lipid profiles (cholesterol categories and triglycerides were determined spectrophotometrically by colorimetric biochemical methods. Obesity was determined by calculation of body mass index (BMI=Kg/m2, waist and hip circumferences and ratio and waist to height ratio.Results: the overall prevalence of obesity ranged from 33.8 to 44.4 % and the overall dyslipidemia prevalence ranged from about 25 to 44% depending on type of dyslipidemia and anthropometrics used. Prevalence of dyslipidemia and mean concentration of lipids profile were generally significantly higher in obese than non obese. The indicator waist/height ratio was the significant predictor for all types of dyslipidemia and all levels of serum lipids.Conclusions: the prevalence dyslipidemia and obesity are high and they are positively associated. Waist/height ratio was the most important predictor of dyslipidemia among adults.

  10. Review of domestic water conservation practices in Saudi Arabia

    Science.gov (United States)

    Ouda, Omar K. M.; Shawesh, Ahmad; Al-Olabi, Tareq; Younes, Firas; Al-Waked, Rafat

    2013-12-01

    The Kingdom of Saudi Arabian (KSA) has a substantial water shortage problem where water demand far exceeds water resources sustainable yields. This fact has motivated the Ministry of Water and Electricity (MOWE) to launch a massive water conservation awareness program to enhance water-using efficiency in the country. The MOWE among other water awareness activities has introduced a four-stage program of free distribution of water conservation tools. This research reviewed the domestic water conservation awareness program in Saudi Arabia and assessed the program performance through conducting questionnaire surveys. The latter was designed and implemented in Al-Khobar city in the Eastern Province to measure public awareness regarding water issues. The survey started on April 28, 2012, and continued for 3 weeks. A total of 197 questionnaires were completed. The survey results showed a relatively low awareness among respondents about water shortage problem in the Kingdom. A low percentage of respondents have water conservation tools installed in their houses, but a high percentage is willing to buy and install water conservation tools. The majority of respondents consider the water price low and are willing to pay more for water. The respondents' feedback highlighted the need to improve the current water conservation awareness program.

  11. Radon exhalation from granites used in Saudi Arabia.

    Science.gov (United States)

    al-Jarallah, M

    2001-01-01

    Measurements of radon exhalation for a total of 50 selected samples of construction materials used in Saudi Arabia were taken using a radon gas analyzer. These materials included sand, aggregate, cement, gypsum, hydrated lime, ceramics and granite. It was found that the granite samples were the main source of radon emanations. A total of 32 local and imported granite samples were tested. It was found that the radon exhalation rates per unit area from these granite samples varied from not detectable to 10.6 Bq m-2 h-1 with an average of 1.3 Bq m-2 h-1. The linear correlation coefficient between emanated radon and radium content was 0.92. The normalized radon exhalation rates from 2.0 cm thick granite samples varied from not detectable to 0.068 (Bq m-2 h-1)/(Bq kg-1) with an average of 0.030 (Bq m-2 h-1)/(Bq kg-1). The average radon emanation of the granite samples was found to be 21% of the total radium concentration. Therefore, granite can be a source of indoor radon as well as external gamma-radiation from the uranium decay series. PMID:11378931

  12. Sleep medicine in Saudi Arabia: Current problems and future challenges

    Directory of Open Access Journals (Sweden)

    BaHammam Ahmed

    2011-01-01

    Full Text Available Sleep medicine is a relatively new specialty in the medical community. The practice of sleep medicine in Saudi Arabia (KSA began in the mid to late nineties. Since its inception, the specialty has grown, and the number of specialists has increased. Nevertheless, sleep medicine is still underdeveloped in the KSA, particularly in the areas of clinical service, education, training and research. Based on available data, it appears that sleep disorders are prevalent among Saudis, and the demand for sleep medicine service is expected to rise significantly in the near future. A number of obstacles have been defined that hinder the progress of the specialty, including a lack of trained technicians, specialists and funding. Awareness about sleep disorders and their serious consequences is low among health care workers, health care authorities, insurance companies and the general public. A major challenge for the future is penetrating the educational system at all levels to demonstrate the high prevalence and serious consequences of sleep disorders. To attain adequate numbers of staff and facilities, the education and training of health care professionals at the level of sleep medicine specialists and sleep technologists is another important challenge that faces the specialty. This review discusses the current position of sleep medicine as a specialty in the KSA and the expected challenges of the future. In addition, it will guide clinicians interested in setting up new sleep medicine services in the KSA or other developing countries through the potential obstacles that may face them in this endeavor.

  13. Automated management of radioactive sources in Saudi Arabia

    International Nuclear Information System (INIS)

    For usage of radioactive substances, any facility has to register and take license from relevant authority of the country in which such facility is operating. In the Kingdom of Saudi Arabia (KSA), the authority for managing radioactive sources and providing licenses to organizations for its usage is the National Center of Radiation Protection (NCRP). This paper describes the system that automates registration and licensing process of the National Center of Radiation Protection. To provide 24×7 accesses to all the customers of NCRP, system is developed as web-based application that provide facility to online register, request license, renew license, check request status, view historical data and reports etc. and other features are provided as Electronic Services that would be accessible to users via internet. The system also was designed to streamline and optimize internal operations of NCRP besides providing ease of access to its customers by implementing a defined workflow through which every registration and license request will be routed. In addition to manual payment option, the system would also be integrated with SADAD (online payment system) that will avoid lengthy and cumbersome procedures associated with manual payment mechanism. Using SADAD payment option license fee could be paid through internet/ATM machine or branch of any designated bank, Payment will be instantly notified to NCRP hence delay in funds transfer and verification of invoice could be avoided, SADAD integration is discussed later in the document

  14. Evaluation of outpatient service quality in Eastern Saudi Arabia

    Science.gov (United States)

    Fraihi, Khalid J. Al; FAMCO, Dip; FAMCO, Fellow; Latif, Shahid A.

    2016-01-01

    Objectives: To investigate perceptions and expectations of patients regarding hospital outpatient services by using a service quality gap model and factors influencing such gaps. Methods: In this cross-sectional descriptive study conducted between October and November 2014 in the outpatient waiting areas of a hospital in the Eastern Province of Saudi Arabia, a sample of 306 patients was selected by convenience sampling technique. The data was collected through an Arabic version of the service quality (SERVQUAL) questionnaire consisting of 2 parts: patients’ demographic characteristics, and 22 items scales of patients’ expectations and perceptions of SERVQUAL. The data was analyzed by confirmatory factor analysis, independent, and paired t samples tests and one way analysis of variance test. Results: The results showed that the proposed model for service quality dimensions had a good fit by satisfying the recommended values. The patients’ expectations exceeded perceptions in all service quality dimensions indicating statistically significant service quality gaps (t=26.3, pmodel is valid and reliable and significant service quality gaps of all 5 dimensions need to be prioritized and addressed by focused improvement efforts of hospital management. PMID:27052285

  15. Use of Dietary Supplements among Professional Athletes in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Sulaiman O. Aljaloud

    2013-01-01

    Full Text Available The objective of this study was to understand the usage patterns of dietary supplements among professional athletes in Saudi Arabia. The survey consisted of sixteen questions divided into four categories: use of supplements, reason for consumption of supplements, personal beliefs about supplements, and behavior. The questionnaires were given to the three teams residing in Riyadh: Al Hilal, Al Nasr, and Al-Shabab. Out of the 105 athletes surveyed, we found that only 98 are currently taking dietary supplements and the mean age and standard deviation were 25.74±2.90. The survey results showed a high percentage of athletes (93.3%; n=98 using different dietary supplements throughout the season, 43.8% (n=43 reported using supplements for performance, and 32.6% (n=32 believed in health benefits as a reason for using dietary supplements. Our results showed that a total of 87 (88.7%, 81 (82.6%, and 51 (52.0% athletes are consuming sports drinks, vitamin C, and multivitamins, respectively. Meanwhile, those supplements ranking among the least used included omega 6 (18.6%, creatine (16.3%, and Ginkgo biloba (10.2%. A majority of athletes indicated that their use of supplements was for the purpose of improving their health and performance.

  16. Causes of Contractors’ Failure in Industrial Projects in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Sadi Assaf

    2015-01-01

    Full Text Available The study aims at identifying and assessing the main causes of contractors’ failure in industrial projects in Saudi Arabia. 24 causes were identified from the literature for assessment by owners, contractors and subcontractors. These causes were classified under five categories, namely managerial causes, financial causes, growth causes, environmental causes and uncontrollable causes. A survey of 36 participants was conducted. Data was collected from 15 owners, 11 contractors and 10 subcontractors. The results indicated that lack of experience in the business field, war, poor project management, poor cost estimation, unavailability of stationed project leader at site, neglect and type of the contract are the most severe causes behind contractor’s failure in construction projects. The rank correlation coefficient indicated that there is a high level of agreement among owners, contractors and subcontractors on the severity of the different failure causes. The research provides a severity of the ranking of the different causes of failure so that mitigation measures could be developed to avoid them or lessen their effects.

  17. Web-based Hierarchical Ordering Mechanism (WHOM) tool for MODIS data from Terra

    Science.gov (United States)

    Sikder, M. S.; Eaton, P.; Leptoukh, G.; McCrimmon, N.; Zhou, B.

    2001-05-01

    At the NASA Goddard Earth Sciences (GES) Distributed Active Archive Center (DAAC), we have substantially enhanced the popular Web-based Hierarchical Ordering Mechanism (WHOM) to include data from the Earth Observing System (EOS). The GES DAAC archives unprecedented volumes of remotely sensed data and large number of geophysical products derived from the MODIS instrument on board Terra satellite, and distributes them to the world scientific and applications user community. These products are currently divided into three groups: Radiometric and Geolocation, Atmosphere, and Ocean data products. The so-called Terra-WHOM (http://acdisx.gsfc.nasa.gov/data/dataset/MODIS/index.html) is a GES DAAC developed search and order user interface which is a smaller segment of the WHOM interface that provides access to all other GES DAAC data holdings. Terra-WHOM specifically provides user access to MODIS data archived at the GES DAAC. It allows users to navigate through all the available data products and submit a data request with minimal effort. The WHOM modular design and hierarchical architecture makes this tool unique, user-friendly, and very efficient to complete the search and order. The main principle of WHOM is that it advertises the available data products, so, users always know what they can get. The WHOM design includes: simple point & click, flexible, web pages generated from templates, consistent look and feel throughout interface, and easy configuration management due to contents being encapsulated and separated from software. Modular search algorithms provide dynamic Spatial and Temporal search capability and return the search results as html pages using CGI scripts. In Terra-WHOM, calendar pages show the actual number of data granules archived for each day for high-resolution local scenes, and from there the user can go to a page showing the geo-coverage for every granule for a given day. This feature significantly optimizes user's effort for selecting data. The

  18. Uso da terra e a qualidade microbiana de agregados de um Latossolo Vermelho-Amarelo

    Directory of Open Access Journals (Sweden)

    Rogério Melloni

    2013-12-01

    Full Text Available A maioria dos estudos relacionados à agregação do solo associa o efeito de manejos ou tipos de uso da terra ao teor de matéria orgânica. No entanto, a avaliação de microrganismos e seus processos, feita diretamente em estruturas indeformadas do solo, permite maior entendimento do real efeito de diferentes tipos de manejos exercidos sobre esse. Assim, o objetivo deste trabalho foi avaliar modificações impostas por diferentes tipos de uso da terra (pastagem, mata de eucalipto, mata com araucária, plantio convencional com cenoura e plantio convencional com abóbora em atributos químicos (pH, Ca, Mg, Al, P, K, S e matéria orgânica e físicos (diâmetro médio geométrico - DMG, diâmetro médio ponderado - DMP, densidade do solo e densidade de partículas e na qualidade microbiana (atividade e carbono microbianos, micélio extrarradicular total de fungos micorrízicos arbusculares e quociente metabólico - qCO2 de classes de tamanho de agregados (I- 4,00 a 2,36 mm; II- 2,36 a 1,18 mm; III- 1,18 a 0,60 mm; IV- 0,60 a 0,30 mm; e V- 0,30 a 0,15 mm de um Latossolo Vermelho-Amarelo, no sul de Minas Gerais. Os resultados evidenciaram que os tipos de uso da terra interferem na formação, no tamanho e na qualidade microbiana dos agregados. Em agregados menores (classes IV e V, há redução de micélio extrarradicular de fungos e biomassa microbiana e aumento da atividade e do quociente metabólico, independentemente do tipo de uso da terra. A qualidade microbiana de agregados maiores do solo sob mata de araucária, com tamanho entre 0,60 e 4,00 mm (I, II e III, é semelhante a todas as classes de tamanho de agregados do solo sob mata de eucalipto, enquanto a de agregados menores de 0,60 mm (IV e V é semelhante a todas de tamanho de agregados da pastagem. Agregados do cultivo convencional, diferentemente dos demais tipos de uso da terra, apresentam baixa qualidade microbiana e relação com a fertilidade do solo.

  19. Validation of MODIS Terra and Aqua Ice Surface Temperatures at Summit, Greenland

    Science.gov (United States)

    Hall, D. K.; Shuman, C. A.; Xiong, X.; Wenny, B. N.; DiGirolamo, N. E.

    2014-12-01

    Ice-surface temperature (IST) is used in many studies, for example for validation of model output and for detection of leads and thin ice in sea ice. The MODerate-resolution Imaging Spectroradiometer (MODIS) instruments on the Terra and Aqua satellites are useful for mapping IST of sea ice and the Greenland ice sheet (Hall et al., 2012), and validation of the ISTs derived from MODIS has been an ongoing effort (e.g., Koenig & Hall, 2010; Shuman et al., 2014). Recent results call into question the calibration of the MODIS-derived ISTs at very cold temperatures that are characteristic of the Greenland ice sheet high interior during winter (Shuman et al., 2014). In the present work, we investigate the calibration of MODIS IR bands 31 (10.780 - 11.280 µm) and 32 (11.770 - 12.270 µm) under very cold conditions. MODIS IR bands are calibrated using a quadratic algorithm. In Collection 6 (C6), the offset and nonlinear calibration coefficients are computed from data collected during the blackbody cool-down vs the warm-up data used in Collection 5 (C5). To improve the calibration accuracy for low-temperature scenes, the offset terms are set to 0. In general, Aqua MODIS bands 31 and 32 perform better than Terra MODIS bands 31 and 32. One of the reasons is that the Aqua bands have a lower saturation temperature (~340 K) than the Terra (~380 K) bands, and lower saturation or smaller dynamic range means better resolution. As compared to ~2-m NOAA air temperatures (TA) at Summit, Greenland, Shuman et al. (2014) show a small (~0.5°C) offset in Terra MODIS-derived IST vs TA near 0°C, and an increasingly larger offset (up to ~5°C) as TA drops to -60°C. To investigate this further, we compare Terra and Aqua C5 and C6 ISTs with TA data from Summit. This work will document the calibration of bands 31 and 32 at very low temperatures in C5 and C6. Hall, D.K., et al., 2012: Satellite-Derived Climate-Quality Data Record of the Clear-Sky Surface Temperature of the Greenland Ice Sheet

  20. Mars Aqueous Processing System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Mars Aqueous Processing System (MAPS) is an innovative method to produce useful building materials from Martian regolith. Acids and bases produced from the regolith...

  1. Mars Solar Balloon Lander Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Solar Balloon Lander (MSBL) is a novel concept which utilizes the capability of solar-heated hot air balloons to perform soft landings of scientific...

  2. 2031, an edaphological Mars odyssey

    Science.gov (United States)

    Barrón, Vidal

    2016-04-01

    NASA is projecting to send humans to Mars in the 2030s. In the PICO session we will make a 4D experience, a journey in space and time. Wéll connect with a meeting in the future mission "Edaphos one" travelling to Mars in 2031. In that meeting, an international scientific team with one geophysicist, one mineralogist and two agronomist will review the state of the art of the geo-edaphological knowledge of the martian surface, based on the main Mars missions using orbiters (Mariner), landers (Viking) and rovers (Pathfinder, Spirit-Opportunity, Curiosity). A special attention will be devoted to the mineralogy of the iron oxides, as important aquamarkers. Finally, they discuss about the biological, physical and chemical limitations for plants growth on Mars. You can see the trailer of the presentation in this link: https://www.youtube.com/watch?v=yRS0tPNpvFU

  3. MARVY: Mars Velocity Sensor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The successful landing of the large Mars rover Curiosity on August 5, 2012 outlined the increasing complexity of safely landing large rovers on the planet. A...

  4. Properties of cryobrines on Mars

    DEFF Research Database (Denmark)

    Möhlmann, D.; Thomsen, Kaj

    2011-01-01

    Brines, i.e. aqueous salty solutions, increasingly play a role in a better understanding of physics and chemistry (and eventually also putative biology) of the upper surface of Mars. Results of physico-chemical modeling and experimentally determined data to characterize properties of cryobrines...... of potential interest with respect to Mars are described. Eutectic diagrams, the related numerical eutectic values of composition and temperature, the water activity of Mars-relevant brines of sulfates, chlorides, perchlorides and carbonates, including related deliquescence relative humidity, are parameters...... and properties, which are described here in some detail. The results characterize conditions for liquid low-temperature brines ("cryobrines") to evolve and to exist, at least temporarily, on present Mars. (C) 2010 Elsevier Inc. All rights reserved....

  5. Manned Mars mission cost estimate

    Science.gov (United States)

    Hamaker, Joseph; Smith, Keith

    1986-01-01

    The potential costs of several options of a manned Mars mission are examined. A cost estimating methodology based primarily on existing Marshall Space Flight Center (MSFC) parametric cost models is summarized. These models include the MSFC Space Station Cost Model and the MSFC Launch Vehicle Cost Model as well as other modes and techniques. The ground rules and assumptions of the cost estimating methodology are discussed and cost estimates presented for six potential mission options which were studied. The estimated manned Mars mission costs are compared to the cost of the somewhat analogous Apollo Program cost after normalizing the Apollo cost to the environment and ground rules of the manned Mars missions. It is concluded that a manned Mars mission, as currently defined, could be accomplished for under $30 billion in 1985 dollars excluding launch vehicle development and mission operations.

  6. Is There Life on Mars?

    Science.gov (United States)

    Allen, Bruce C.; Herreid, Clyde Freeman

    1998-01-01

    Presents a conflict scenario for a case study on whether there is evidence of past life on Mars. Includes details about the use of this case study in developing an interdisciplinary approach to scientific ethics. (DDR)

  7. Mars Regolith Water Extractor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Regolith Water Extractor (MRWE) is a system for acquiring water from the Martian soil. In the MRWE, a stream of CO2 is heated by solar energy or waste heat...

  8. An Overview of Mars Vicinity Transportation Concepts for a Human Mars Mission

    Science.gov (United States)

    Dexter, Carol E.; Kos, Larry

    1998-01-01

    To send a piloted mission to Mars, transportation systems must be developed for the Earth to Orbit, trans Mars injection (TMI), capture into Mars orbit, Mars descent, surface stay, Mars ascent, trans Earth injection (TEI), and Earth return phases. This paper presents a brief overview of the transportation systems for the Human Mars Mission (HMM) only in the vicinity of Mars. This includes: capture into Mars orbit, Mars descent, surface stay, and Mars ascent. Development of feasible mission scenarios now is important for identification of critical technology areas that must be developed to support future human missions. Although there is no funded human Mars mission today, architecture studies are focusing on missions traveling to Mars between 2011 and the early 2020's.

  9. Mars Image Collection Mosaic Builder

    Science.gov (United States)

    Plesea, Lucian; Hare, Trent

    2008-01-01

    A computer program assembles images from the Mars Global Surveyor (MGS) Mars Observer Camera Narrow Angle (MOCNA) collection to generate a uniform-high-resolution, georeferenced, uncontrolled mosaic image of the Martian surface. At the time of reporting the information for this article, the mosaic covered 7 percent of the Martian surface and contained data from more than 50,000 source images acquired under various light conditions at various resolutions.

  10. Adoption of Mobile Banking in Saudi Arabia : An Emprical Evaluation Study

    Directory of Open Access Journals (Sweden)

    Ayman N. Alkhaldi

    2016-05-01

    Full Text Available This study explores the adoption of mobile banking practices in Saudi Arabia. It focuses on the existence of sufficient infrastructure, and the possible challenges that m-banking services may face. Also, discovers the potential opportunities in the country. A sample of banks in Saudi Arabia was surveyed via questionnaire, with a particular focus on the staff in the related IT departments. The findings demonstrate that although m-banking is believed to be important, there is a general lack of awareness, and it is still not widely accepted by the public. M-banking services provided should be easier to use and offer more security to its users. Furthermore, findings reveal that cooperation among the concerned parties is currently not extensive. From this, the researcher recommends that governing regulations and policies should be properly identified and put in place, and proposes that banking decision-makers in Saudi Arabia should reevaluate their bank’s strategic plans.

  11. Recurrent appearance of foot and mouth disease virus (FMDV in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    A.F. Alsayeqh

    2012-09-01

    Full Text Available There are seven immunologically distinct serotypes of FMDV (O, A, C, Asia 1, SAT 1, SAT 2 and SAT 3, most of them were detected and identified in different regions of Saudi Arabia. FMDV serotype O was the most frequent strain in last decade. Outbreaks of FMDV repeatedly occur among cattle, sheep and goats in various regions of Saudi Arabia during years 1994, 1995, 2000, 2004, 2005, 2006, 2008 and 2010. Recently, 14 (0.78 % suspected cases of FMDV out of inspected 1800 cows were observed and recorded during Hajj season 1432 H (2011 in Makkah. Prevention and control strategies of FMD in Saudi Arabia particularly during Hajj seasons were discussed.

  12. Exports and Economic Growth in Saudi Arabia: A VAR Model Analysis

    Science.gov (United States)

    Alhajhoj, Hassan

    Kingdom of Saudi Arabia is a developing country and is rich in natural resources. The export sector plays an important role in the economic growth of a country. Basically, economic growth of a country depends on the nature and type of relationship between exports and domestic economic growth. Modern econometric techniques such as Vector Auto-Regression (VAR), Impulse Response Function (IFR) and the Granger-causality test were applied to determine long-term relationship between exports and domestic economic growth from 1970 to 2005. It was found that the export sector of Saudi Arabia caused a significant effect on the economic growth and a positive influence on other economic activities in the long run. Also, a long-term equilibrium existed among the various macroeconomic variables such as RGDP, RC, RG, RI, RX and RM considered in the study. It is apparent that a steady state condition can be reached between exports and economic growth in Saudi Arabia.

  13. Europe's eye on Mars: first spectacular results from Mars Express

    Science.gov (United States)

    2004-01-01

    Although the seven scientific instruments on board Mars Express are still undergoing a thorough calibration phase, they have already started collecting amazing results. The first high-resolution images and spectra of Mars have already been acquired. This first spectacular stereoscopic colour picture was taken on 14 January 2004 by ESA’s Mars Express satellite from 275 km above the surface of Mars by the High Resolution Stereo Camera (HRSC). This image is available on the ESA portal at: http://mars.esa.int The picture shows a portion of a 1700 km long and 65 km wide swath which was taken in south-north direction across the Grand Canyon of Mars (Valles Marineris). It is the first image of this size that shows the surface of Mars in high resolution (12 metres per pixel), in colour, and in 3D. The total area of the image on the Martian surface (top left corner) corresponds to 120 000 km². The lower part of the picture shows the same region in perspective view as if seen from a low-flying aircraft. This perspective view was generated on a computer from the original image data. One looks at a landscape which has been predominantly shaped by the erosional action of water. Millions of cubic kilometres of rock have been removed, and the surface features seen now such as mountain ranges, valleys, and mesas, have been formed. The HRSC is just one of the instruments to have collected exciting data. To learn more about the very promising beginning to ESA's scientific exploration of Mars, media representatives are invited to attend a press conference on Friday, 23 January 2004, at 11:00 CET at ESA’s Space Operations Centre in Darmstadt, Germany, and in video-conference with the other ESA centres. There, under the auspices of ESA Council Chair at Ministerial level, Germany's Minister for Education and Research, Mrs Edelgard Bulmahn, ESA's Director of the Scientific Programme, Prof. David Southwood and the Principal Investigators of all instruments on board Mars Express will

  14. Site selection for Mars exobiology

    Science.gov (United States)

    Farmer, J.; Des Marais, D.; Greeley, R.; Landheim, R.; Klein, H.

    1995-01-01

    The selection of sites on Mars that have a high priority for exobiological research is fundamental for planning future exploration. The most immediate need is to identify targets for high resolution orbital imaging during the Mars Observer and Mars '94/'96 missions that can be used to refined site priorities for surface exploration. We present an objective approach to site selection whereby individual sites are selected and scored, based on the presence of key geological features which indicate high priority environments. Prime sites are those that show evidence for the prolonged activity of liquid water and which have sedimentary deposits that are likely to have accumulated in environments favorable for life. High priority areas include fluvio-lacustrine (stream-fed lake systems), springs, and periglacial environments. Sites where mineralization may have occurred in the presence of organisms (e.g. springs) are given high priority in the search for a fossil record on Mars. A systematic review of Viking data for 83 sites in the Mars Landing Site Catalog (MLSC) resulted in the selection of 13 as being of exobiological interest. The descriptions of these sites were expanded to address exobiological concerns. An additional five sites were identified for inclusion in the second edition of the MLSC. We plan to broaden our site selection activities to include a systematic global reconnaissance of Mars using Viking data, and will continue to refine site priorities for exobiological research based on data from future missions in order to define strategies for surface exploration.

  15. Mars geodesy, rotation and gravity

    International Nuclear Information System (INIS)

    This review provides explanations of how geodesy, rotation and gravity can be addressed using radioscience data of an orbiter around a planet or of the lander on its surface. The planet Mars is the center of the discussion. The information one can get from orbitography and radioscience in general concerns the global static gravitational field, the time variation of the gravitational field induced by mass exchange between the atmosphere and the ice caps, the time variation of the gravitational field induced by the tides, the secular changes in the spacecraft's orbit induced by the little moons of Mars named Phobos and Deimos, the gravity induced by particular targets, the Martian ephemerides, and Mars' rotation and orientation. The paper addresses as well the determination of the geophysical parameters of Mars and, in particular, the state of Mars' core and its size, which is important for understanding the planet's evolution. Indeed, the state and dimension of the core determined from the moment of inertia and nutation depend in turn on the percentage of light elements in the core as well as on the core temperature, which is related to heat transport in the mantle. For example, the radius of the core has implications for possible mantle convection scenarios and, in particular, for the presence of a perovskite phase transition at the bottom of the mantle. This is also important for our understanding of the large volcanic province Tharsis on the surface of Mars. (invited reviews)

  16. Recurrent appearance of foot and mouth disease virus (FMDV) in Saudi Arabia

    OpenAIRE

    A.F. Alsayeqh; shawkat mohamed fathi

    2012-01-01

    There are seven immunologically distinct serotypes of FMDV (O, A, C, Asia 1, SAT 1, SAT 2 and SAT 3), most of them were detected and identified in different regions of Saudi Arabia. FMDV serotype O was the most frequent strain in last decade. Outbreaks of FMDV repeatedly occur among cattle, sheep and goats in various regions of Saudi Arabia during years 1994, 1995, 2000, 2004, 2005, 2006, 2008 and 2010. Recently, 14 (0.78 %) suspected cases of FMDV out of inspected 1800 cows were observed and...

  17. Phthiria sharafi sp. nov., a new record of the subfamily Phthiriinae (Bombyliidae, Diptera) from Saudi Arabia.

    Science.gov (United States)

    El-Hawagry, Magdi S; Al Dhafer, Hathal M

    2014-01-01

    This new species (Phthiria sharafi sp. nov.) represents the first record of the subfamily Phthiriinae (Bombyliidae, Diptera) from Saudi Arabia. The species was collected from Garf Raydah Protected Area, Abha, Asir Province, south-western part of Saudi Arabia, using a Malaise trap erected in a site rich in olive, cactus and Juniper trees. The type locality has an Afrotropical influence, with the Afrotropical elements predominant, and a closer affiliation to the Afrotropical region than to the Palearctic region or the Eremic zone.  PMID:25544092

  18. Prevalence and Pattern of Refractive Errors among Primary School Children in Al Hassa, Saudi Arabia

    OpenAIRE

    Wadaani, Fahd Abdullah Al; Amin, Tarek Tawfik; Ali, Ayub; Khan, Ataur Rahman

    2012-01-01

    Some 12.8 million in the age group 5–15 years are visually impaired from uncorrected or inadequately corrected refractive errors. In Saudi Arabia, the size of this public health problem is not well defined especially among primary schoolchildren. The purpose of this cross-sectional study was to assess the prevalence and pattern of refractive errors among primary school children in Al Hassa, Saudi Arabia. A total of 2246 Saudi primary school children aged 6 to 14 years of both genders were sel...

  19. Climate change and epidemiology of human parasitoses in Saudi Arabia: A review

    Directory of Open Access Journals (Sweden)

    Wael Mohamed Lotfy

    2016-07-01

    Full Text Available Climate change is an emerging global problem. It has hazardous effects that vary across different geographic regions and populations. It is anticipated to have significant effects in Saudi Arabia. The present work reviews the future of human parasitoses in Saudi Arabia in response to the expected climate change. The key projections are increased precipitations, flash floods, unstable temperatures, sea-level rise and shoreline retreat. Such environmental changes could strongly influence the epidemiology of fly-borne, mosquito-borne, snail-borne and water-borne human parasitoses in the country.

  20. Mapping the epidemiology and trends of extra-pulmonary tuberculosis in Saudi Arabia.

    Science.gov (United States)

    Varghese, Bright; Al-Hajoj, Sahal

    2015-12-01

    An extra-pulmonary tuberculosis (EPTB) infection rate of 30% in Saudi Arabia remains above the global rate. A variable rate of infection in each province has been reported and the involvement of most organs has been cited. Nationwide collective data on the current trends of infection are scarce and the factors behind the increased rate of EPTB are perplexing. This review endeavors to shed light into the epidemiology of EPTB, various types of infections sites, geographical differences in the infection rate, known risk factors, and challenges in the diagnosis and management of EPTB in Saudi Arabia.