Oehler, Dorothy Z.; Allen, Carlton C.
Hydrothermal springs are important astrobiological sites for several reasons: 1) On Earth, molecular phylogeny suggests that many of the most primitive organisms are hyperthermophiles, implying that life on this planet may have arisen in hydrothermal settings; 2) on Mars, similar settings would have supplied energy- and nutrient-rich waters in which early martian life may have evolved; 3) such regions on Mars would have constituted oases of continued habitability providing warm, liquid water to primitive life forms as the planet became colder and drier; and 4) mineralization associated with hydrothermal settings could have preserved biosignatures from those martian life forms. Accordingly, if life ever developed on Mars, then hydrothermal spring deposits would be excellent localities in which to search for morphological or chemical remnants of that life. Previous attempts to identify martian spring deposits from orbit have been general or limited by resolution of available data. However, new satellite imagery from HiRISE has a resolution of 28 cm/pixel which allows detailed analysis of geologic structure and geomorphology. Based on these new data, we report several features in Vernal Crater, Arabia Terra that we interpret as ancient hydrothermal springs.
Michalski, Joseph R; Bleacher, Jacob E
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 possess 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 sulphur and erupted fine-grained pyroclastics from these calderas probably fed the formation of altered, layered sedimentary rocks and fretted terrain found throughout the equatorial region. The 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. PMID:24091975
Pozzobon, Riccardo; Pio Rossi, Angelo; Massironi, Matteo; Mazzarini, Francesco; Pondrelli, Monica; Marinangeli, Lucia; Unnithan, Vikram
Arabia Terra is a region of Mars located at the boundary between the southern highlands and the northern lowlands and classically dominated by heavily cratered terrain. Unlike the rest of the topographic dichotomy on the planet, in Arabia Terra the elevation transition is very gentle, falling of 4 km over a distance of 2500 km (average slope = 0.0016°). Most of the impact craters within the region display a central bulge, bearing a well preserved stratification and a wide range of smaller morphologies like pitted cones, mounds and knobs (Franchi et al. 2013). Images acquired by HiRISE and CTX cameras on board MRO provided a comprehensive dataset in which also these small features can be easily recognized. These are tens of meters of diameter and tens of meters high, and many of them show an apical orifice. They are interpreted to have worked as pathways for subsurface fluid flow (e.g. Pondrelli et al., 2011; Rossi et al., 2008). Indeed an active underground fluid flow activity in Arabia Terra It has been recently hypothesized (e.g. Andrews-Hanna et al, 2011) , being crater central bulges a place of sulfate precipitation, due to local water table emergence (e.g. Franchi et al., 2013). To date, there is no clear explanation for occurrence of central bulges surrounded by prominent depressions in Arabia craters. In addition, in Firsoff and Crommelin craters it is possible to recognize folds and outward dipping strata on the central bulges and their surroundings. Interestingly, a few craters with a prominent bulged floor elsewhere in Arabia Terra do not display stratification and are not explainable as impact related structures as their expected pristine central peak derived by hydrocode modelling is ~2km lower and one third the diameter than the actual topography (Pozzobon et al., 2013). All these evidences are not consistent with a typical lacustrine stratigraphic environment, whether interested by sulfate precipitation or not, and suggest active deformation after or
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.
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.
Silvestro, S.; Vaz, D.A.; Fenton, L.K.; Geissler, P.E.
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.
Allen, C. C.; Oehler, D. Z.; Paris, K. N.; Venechuk, E. M.
Understanding the habitability of ancient Mars is a key goal in the exploration of that planet. Evidence for conditions favorable to early life must be sought in ancient sedimentary rocks, such as those of Arabia Terra and Meridiani Planum. Arabia Terra, the northernmost extension of the ancient highlands, is dominated by cratered plains and minor ridged units. These plains extend south into the adjacent Meridiani Planum. The Opportunity rover landed in northern Meridiani, close to the border with Arabia. High resolution MOC images reveal extensive layered sequences across much of the Arabia and Meridiani region. These layers have been interpreted as eroded remnants of sedimentary rock deposits (Edgett, 2005). The layered sequences are concentrated in the SW quadrant of Arabia and in northern Meridiani. Preliminary mapping by Edgett (2005) distinguished four large scale layered sequences in the Arabia and Meridiani region. These have dimensions of hundreds to more than 1,000 km. MOLA altimetry shows that each of the sequences can attain a thickness of 200 to 400 m, with a total thickness greater than 1 km. The sequences are generally flat lying, with regional slopes of a few degrees. Much finer layering is evident within a number of craters. The plains and ridged units of the Arabia and Meridiani region were originally mapped as Noachian based on crater statistics, particularly the number of large craters (Scott and Carr, 1978). The layered sequences in the current study postdate many, but not all, of these large craters. The layered sequences have partially or totally filled a number of craters with diameters ranging from 20 to over 50 km. The topmost layered sequence, as well as the lower two sequences, have intermediate thermal inertia, as derived from THEMIS, indicative of moderate induration. The TES spectra from the lower sequences include features indicative of basalt. Some areas of the topmost sequence, which includes the Opportunity landing site, have TES
Robbins, S. J.; Hynek, B. M.
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.
Rodriguez, J.A.P.; Tanaka, K.L.; Yamamoto, A.; Berman, D.C.; Zimbelman, J.R.; Kargel, J.S.; Sasaki, S.; Jinguo, Y.; Miyamoto, H.
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
Bleacher, Jacob; Michalski, Joseph
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
[figure removed for brevity, see original site] This scene from the dust covered plains of eastern Arabia Terra portrays a range of geological time. Three craters at the center of the image capture some of this range. Two have the classic bowl-shape of small, relatively recent craters while the one just to the north has seen much more history. Its rim has been scoured away by erosion and its floor has been filled in by material likely of a sedimentary nature. The channels that wind through the scene may be the oldest features present while the relatively dark streaks scattered about could have been produced in the past few years or even months as winds remove a layer of dust to reveal darker material below.Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, 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.
Harrington, B. W.; Phillips, R. J.; Golombek, M. P.
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.
Dohm, James M.; Barlow, Nadine; Williams, Jean-Pierre; Baker, Victor R.; Anderson, Robert C.; Boynton, William V.; Fairen, Alberto G.; Hare, Trent M.
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 , 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 ), 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  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.
Anderson, R. C.; Dohm, J. M.; Robbins, S.; Schroeder, J.
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.
Anderson, R. C.; Dohm, J. M.; Robbins, S.; Hynek, B.; Andrews-Hanna, J.
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.
Wong, M. P.; Sakimoto, S. E. H.; Garvin, J. B.
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.
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,…
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.
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 , 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.
Dohm, J. M.; Barlow, N. G.; Williams, Jean-Pierre; Ferris, J. C.; Miyamoto, H.; Baker, V. R.; Boynton, W. V.; Strom, R. G.; Rodriguez, Alexis; Fairen, Alberto G.
Ancient geologic and hydrologic phenomena on Mars observed through the magnetic data provide windows to the ancient past through the younger Argyre and Hellas impacts, the northern plains basement and the rock materials that mantle the basement, and the Tharsis and Elysium magmatic complexes (recently referred to as superplumes). These signatures, coupled with highly degraded macrostructures (tectonic features that energetic planet during its embryonic development (0.5 Ga or so of activity) with an active dynamo and magnetosphere. One such window into the ancient past occurs northwest of the Hellas impact basin in Arabia Tern. Arabia Terra is one of the few water-rich equatorial regions of Mars, as indicated I through impact crater and elemental information. This region records many unique characteristics, including predominately Noachian materials, a highland-lowland boundary region that is distinct from other boundary regions, the presence of very few macrostructures when compared to the rest of the cratered highlands, the largest region of fretted terrain on Mars, outflow channels such as Mamers Valles that do not have obvious origins, and distinct albedo, thermal inertia, gravity, magnetic, and elemental signatures.
Hauber, E.; Gwinner, K.; Kleinhans, M.; Reiss, D.; Di Achille, G.; Ori, G.-G.; Scholten, F.; Marinangeli, L.; Jaumann, R.; Neukum, G.
A variety of sedimentary deposits is observed in Xanthe Terra, Mars, including Gilbert-type deltas, fan deltas dominated by resedimentation processes, and alluvial fans. Sediments were provided through deeply incised valleys, which were probably incised by both runoff and groundwater sapping. Mass balances based on High-Resolution Stereo Camera (HRSC) digital terrain models show that up to ˜30% of the material that was eroded in the valleys is present as deltas or alluvial fan deposits. Stratigraphic relationships and crater counts indicate an age of ˜4.0 to ˜3.8 Ga for the fluvial activity. Hydrologic modeling indicates that the deposits were probably formed in geologically very short time scales. Our results point to episodes of a warmer and wetter climate on early Mars, followed by a long period of significantly reduced erosion rates.
Hobbs, S. W.; Clarke, J. D. A.; Paull, D. J.
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.
den Haan, J.; Zegers, T. E.; van Ruitenbeek, F. J. A.; van der Werff, H. M. A.; Rossi, A.
Introduction The discovery of phyllosilicates on Mars  has had major implications on the perceived geologic and climatologic evolution of Mars . 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. ) 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 . The ratio of
Zimbelman, J. R.; Johnson, M. B.
The High Resolution Imaging Science Experiment (HiRISE) has revealed abundant wind ripples on sand dunes across Mars. Ripple orientations have been documented using HiRISE images of sand dunes at 24 widely distributed sites across Mars, in order to identify the last significant wind directions at these locations. Howard (GSAB, 1977) gives a mathematical expression for how surface slopes on a sand dune can affect the orientation of ripples with respect to the formative winds. In order to evaluate this mechanism for measured ripple orientations on Mars, quantitative data for surface slopes on the sand dunes is required. Stereo pairs of HiRISE images are used to generate Digital Terrain Models (DTMs) with postings of one meter. In June 2014 we produced a DTM of sand dunes in the Terra Tyrrhena region of Mars (14.55° S, 97.77° E) using SOCET SET at the Astrogeology Branch, USGS-Flagstaff. Typically it is difficult for feature matching software to work well on sand dunes, but our stereo images (ESP_022609_1655 and ESP_026675_1655) were obtained only six Earth days apart under excellent illumination conditions. The Terra Tyrrhena DTM had remarkably few artifacts on the sand dunes (except at slip faces, where the average slope between slip face crest and base was interpolated) and excellent control from irregular terrain exposed in interdune areas. Slopes on the stoss sides of sand dunes are generally ripple deflection angles should be ripple orientations to account for surface slopes utilizing the DTM data, and so far we do not see major changes to inferred surface wind directions that would be derived directly from the ripple orientations.
Skiner, J. A., Jr.; Rogers, A. D.; Seelos, K. D.
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.
Schon, S.; Head, J.; Fassett, C.
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 . 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
Arvidson, R. E.; Deal, K.; Hynek, B. M.; Seelos, F. P., IV; Snider, N. O.; Mellon, M. T.; Garvin, J. B.
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.
Irwin, R. P., III; Grant, J. A.
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  and 1:15M scales , 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.
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.
Thomas M. Missimer
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.
Hobbs, S. W.; Paull, D. J.; Clarke, J. D. A.; Roach, Ian C.
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.
Sefton-Nash, E.; Fawdon, P.; Gupta, S.; Balme, M.; Davis, J; Grindrod, P.; Sidiropoulos, P.; Yershov, V.; Muller, J.-P.
The search for life on Mars is a cornerstone of international solar system exploration. In 2018, the European Space agency will launch the ExoMars Rover to further this goal. The key science objectives of the ExoMars Rover are to: 1) search for signs of past and present life on Mars; 2) investigate the water/geochemical environment as a function of depth in the shallow subsurface; and 3) to characterize the surface environment. ExoMars will drill into the sub-surface to look for indicators of...
Skinner, J. A., Jr.; Rogers, A. D.; Seelos, K. D.
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.
Rogers, A.D.; Fergason, R.L.
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. Copyright ?? 2011 by the American Geophysical Union.
Elkins-Tanton, Linda T
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
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.
Wahl, Manfred W.
The overarching goal of the InfoTerra/TerraSAR Initiative is to establish a self-sustaining operational/commercial business built on Europe"s know-how and experience in space-borne Synthetic Aperture Radar (SAR) technology, in SAR data processing as well as in SAR applications. InfoTerra stands for a new business concept based on supplying innovative geo-information products and services. TerraSAR is a space and ground system conceived to consist of an initial deployment and operation of 2 Radar satellites (one in X- and one in L-band) flying in a tandem configuration in the same orbit. The design of TerraSAR is driven by the market and is user-oriented. TerraSAR is key to capturing a significant proportion of the existing market and to opening new market opportunities, when it becomes operational. The InfoTerra/TerraSAR Initiative has evolved gradually. It started in 1997 as a joint venture between German (DSS) and British (MMS-UK) space industry, strongly supported by both space agencies, DLR and BNSC. In early 2001, DLR and BNSC submitted to ESA the Formal Programme Proposal for InfoTerra/TerraSAR to become an essential element of ESA"s Earth Watch Programme. In summer 2001, when it became evident that there was not yet sufficient support from the ESA Member States to allow immediate start entering into TerraSAR Phase C/D, it has been decided to implement first a TerraSAR consolidation phase. In early 2002, in order to avoid further delays, a contract was signed between DLR and Astrium GmbH on the development of one component of TerraSAR, the TerraSAR-X, in the frame of a national programme, governed by a Public Private Partnership Agreement. Even if now the different launch dates for TerraSAR-X and TerraSAR-L are narrowing down the window of common data acquisition, it is a reasonable starting point, but it should always be kept in mind that the utmost goal for the longterm is to achieve self sustainability by supplying geo-information products and services
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.)
Arvidson, R.E.; Grotzinger, J.; Ehlmann, B. L.
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...
Farmer, Jack D.; Desmarais, David J.
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
Paula Simas de Andrade
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.
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
Barclay, Tom; Eberl, Robert; Gray, Jim; Nordlinger, John; Raghavendran, Guru; Slutz, Don; Smith, Greg; Smoot, Phil; Hoffman, John; Robb III, Natt; Rossmeissl, Hedy; Duff, Beth; Lee, George; Mathesmier, Theresa; Sunne, Randall
The Microsoft TerraServer stores aerial and satellite images of the earth in a SQL Server Database served to the public via the Internet. It is the world's largest atlas, combining five terabytes of image data from the United States Geodetic Survey, Sovinformsputnik, and Encarta Virtual Globe. Internet browsers provide intuitive spatial and gazetteer interfaces to the data. The TerraServer is also an E-Commerce application. Users can buy the right to use the imagery using Microsoft Site Serve...
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...
Bish, D. L. (David L.); Vaniman, D. T. (David T.); Fialips, C. I. (Clair I.); Carey, J. W. (James W.); Feldman, W. C. (William C.)
Great interest was generated with the discovery by the Odyssey spacecraft OC heterogeneously distributed hydrogcn at martian mid-latitudes, suggesting that large areas of the near-equatorial highlands contain near-surface deposits of 'chemically and/or physically bound 1120 and/or OH' in amounts up to 3.8% equivalent H20. More recent interpretations of the Odyssey data using new calibrations suggest that some near-equatorial areas, such as Arabia Terra, contain up to 8.5f I .3% water-equivalent hydrogen. Such shallow occurrences (Mars, and both groups of minerals are common terrestrial alteration products of hydrovolcanic basaltic ashes and palagonitic material comparable io those that may be widespread on Mars. Smectites within martian meteorites, attributed to hydrous alteration on Mars rather than on Earth, provide direct evidence of clay minerals from Mars. In addition, new thermal emission spectrometer (TES) data provide evidence for unspecified zeolites in martian surface dust, and concluded that spectral deconvolution of MGS TES and Mariner 9 IRIS data is consistent with the presence of zeolite in the martian surface dust.
Full Text Available TerraSAR-X è sviluppato ed operato dall’Agenzia Spaziale Tedesca (DLR, Deutsches Zentrum für Luft- und Raumfahrt e da EADS Astrium con l’obiettivo di essere il primo satellite per osservazione della Terra (EO in grado di fornire globalmente e con continuità dati radar in banda X. La tecnologia Radar ad Apertura Sintetica (SAR realizzata in banda X, cioè a frequenze superiori rispetto a quelle delle bande C ed L usate in precedenza in altre missioni, permetterà di fornire servizi con risoluzioni variabili tra 1 e 16 metri.
This image of the Terra Sirenum region of Mars was taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) at 0918 UTC (4:18 a.m. EST) on Nov. 25, 2006, near 38.9 degrees south latitude, 195.9 degrees east longitude. CRISM's image was taken in 544 colors covering 0.36-3.92 micrometers, and shows features as small as 18 meters (60 feet) across. At this time, Mars' southern hemisphere was experiencing mid-winter. During Martian southern winter, the southern polar cap is covered and surrounded by carbon dioxide frost and water frost. This is unlike Earth, whose frozen winter precipitation is made up of only one volatile -- water. The carbon dioxide frost evaporates, or sublimates, at a lower temperature than water frost. So, during spring, the carbon dioxide ice evaporates first and leaves a residue of water frost, which later sublimates as well. The image shown here covers part of a crater rim, which is illuminated from the upper left. North is at the top. The topography creates a cold microenvironment on the south side of the rim that is partially protected from solar illumination. That cold surface contains an outlier of the southern seasonal frost about 15 degrees of latitude closer to the equator than the average edge of the frost at this season. The top image was constructed from three infrared wavelengths that highlight the bluer color of frost than the background rock and soil. Note that the frost occurs both on sunlit and shaded surfaces on the south side of the rim. The shaded areas are still visible because they are illuminated indirectly by the Martian sky. The bottom image was constructed by measuring the depths of spectral absorption bands due to water frost and carbon dioxide frost, and displaying the results in image form. Blue shows strength of an absorption due to water frost near 1.50 micrometers, and green shows strength of an absorption due to carbon dioxide frost near 1.45 micrometers. Red shows brightness of the surface at 1
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
Encarnação, José d'
Recensão do livro «Terra Fria Terra Quente», de Maria José Corrêa Pinto. Salienta-se o facto de constituir um romance de costumes, pois dá a conhecer a vida da cidade de Chaves nos derradeiros anos da II Grande Guerra, demorando-se na descrição de tradições transmontanas e, também, dos costumes da tribo moçambicana dos Macuas.
Baioni, D.; Sgavetti, M.; Tampella, G.; Wezel, F. C.
In the Terra Meridiani- Arabia Terra region of Mars, layered rock units with a range of stratal patterns have been widely reported in the literature, and the record of the spectral signatures indicative of hydrate minerals suggests the existence of aqueous activity in at least some of the stratigraphic units. . In this work we investigated the area in the northern region of Sinus Meridiani located between 2°N to 3°N latitude and 2°W to 1°E longitude, using multiple remote sensing data sets to identify, characterize in detail, and understand the origin and evolution of the selected units in this region of Mars. MOLA and HiRISE data were used in combination to classify and correlate surface units recorded in distinct stratigraphic logs, based on planimetric configuration, topography, morphological and litho-facies characteristics. In particular, detailed analyses were focused on the layered units discovered in the walls of two impact craters located at a distance of about 100 km to each other within the study area. The stratigraphic interval analysed here corresponds to the upper part of the well known "light-toned layered deposits" identified by several authors. Distinct competent layers are observed in the internal slopes of both craters. Our observations indicate that the lithostratigraphic sections can be divided in three units. The lower unit consists of very thick bodies of light-toned bouldery breccia deposits. In the HiRISE images these white-coloured beds are composed of irregularly-shaped, white nodules which are either isolated or coalescent, distributed between bedding planes. The middle unit mainly consists of alternating thin strong layers and thicker sequences of relatively weak layers, horizontally bedded. The strong, competent layers maintain steeper erosional profiles and play a major role in controlling the overall shape and geomorphology of the wall slopes. The upper unit can be traced laterally in the surrounding ground level, displaying mesa
There are three main highland areas on Venus: Beta Regio, Ishtar Terra and Aphrodite Terra. The latter is least known and the least mapped, yet existing analyses of Aphrodite Terra based on available Pioneer-Venus orbiter data suggest that it may be the site of extensive rifting. Some of the highest resolution (30 km) PV data (SAR) included most of the western half of Aphrodite Terra. Recent analysis of the SAR data together with Arecibo range-doppler topographic profiling (10 X 100 km horizontal and 10 m vertical resolution) across parts of Aphrodite, further characterized the nature of possible tectonic processes in the equatorial highlands. The existence of distinct topographic and radar morphologic linear discontinuities across the nearly east-west strike of Aphrodite Terra is indicated. Another prominent set of linear features is distinctly parallel to and orthogonal to the ground tracks of the PV spacecraft and are not included because of the possibility that they are artifacts. Study of the northwest trending cross-strike discontinuities (CSD's) and the nature of topographic and morphologic features along their strike suggest the presence of bilateral topographic and morphologic symmetry about the long axis of Aphrodite Terra
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
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. . 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. . 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
Steele, Liam J.; Lewis, Stephen R.; Patel, Manish R.; Montmessin, Franck; Forget, Francois; Smith, Michael D.
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.
Smith, David E.; Zuber, Maria T.
The presence of large impact basins and the low northern plains that might have contained ice or liquid water at an earlier stage of Mars evolution suggests that the global gravity field could have been different in the distant past than it is today. In addition, any significant change in the distribution of mass affects the moments of inertia and consequently and could conceivably change the position of the pole and the length of day. Similar effects could have been produced by large erosional processes, such as the removal of crustal material from the Arabia Terra region and subsequent re-deposition in the Chryse region of the northern plains. We have endeavored to estimate the magnitudes of material that might have been involved in these processes and their possible effect on the gravity and dynamics of Mars. We have used present-day topography and gravity field as a starting point, recognizing that both the result of the processes that we are trying to study rather than the state at the times of interest.
Aycan Özden Sezgin
Full Text Available Terra firma-forme dermatosis (TFFD is an asymptomatic keratinization disorder of an unknown etiology which is characterized by dirt like brown hyperpigmented papillomatous plaques. Development of lesions is not associated with a hygiene disorder. The most important feature of the disease is that the lesions can not be removed by washing with soap and water, while they can only be removed by rubbing with 70% isopropyl alcohol or ethyl alcohol. Here, we present a child with terra firma-forme dermatosis who has been previously diagnosed as epidermal nevus.
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
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
Oztürk, Ferdi; Kocabaş, Engin; Ertan, Pelin; Ermertcan, Aylin Türel
Terra firma-forme dermatosis (TFFD) is an uncommon disorder of keratinization with an unknown etiology in which patients present with dirt-like lesions that are resistant to washing. A 6-year old girl presented with the complaint of an asymptomatic brownish black dirt-like eruption on her body. Her parents reported no response to washing with soap and water. Dermatologic examination revealed brown hyperpigmented patches on the trunk and abdominal region. TFFD was suspected, and isopropyl alcohol was applied to the patient's lesions. All lesions completely disappeared after rubbing with alcohol. Terra firma-forme dermatosis is a relatively recently described entity that is much more common than might be expected when surveying the medical literature. With the very few reports found in the literature about TFFD, we believe that an increased awareness of this entity among primary care physicians would help decrease unnecessary worries or medical procedures, since TFFD lesions simply resolve by rubbing with isopropyl alcohol. PMID:20684734
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.
We described a Saudi patient infected with Diphyllobothrium latum D. latum. A 38-year-old male presented, complaining of passing worms. He had a history of recent travel to Europe and South East Asia. Stools examination revealed typical D. latum eggs. He was treated with praziquantel followed by saline purge, after which he discharged an intact tapeworm. Macroscopic and microscopic examinations of the worm confirmed the diagnosis of D. latum. This is the first case of diphyllobothriasis to be reported in Saudi Arabia. The epidemiology and methods of prevention of diphyllobothriasis are discussed. (author)
Ding, M.; Lin, J.; Zuber, M. T.
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
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.
Anagha Ramesh Babu
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.
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)
Energy and the Saudi economy were discussed with reference to reserves, oil prices, gross domestic product co-movements, and gas resources and development. In particular, this presentation reviewed the emergence and prospects of the petrochemical industry of Saudi Arabia using statistical, institutional and economic analyses relying on a wide range of data sources. Saudi Arabia has the world's largest oil reserves, at 263 billion barrels. In the 1990s, more than 54 Tcf of non-associated gas reserves were added to Saudi Arabia's resource base, more than doubling its proven non-associated gas reserves to approximately 97 Tcf. With 138 Tcf of associated gas reserves, Saudi Arabia holds the fourth largest gas reserves in the world at nearly 235 Tcf. First, this presentation identified and evaluated the endowments as well as the institutional and strategic forces that are driving the growth of the petrochemical industry in Saudi Arabia. Some of the economic, technical and geopolitical factors that influenced the increase in oil prices between 2003 and 2005 were also identified. The dual relationship between the Saudi petrochemical industry and long term economic performance of the Saudi economy were illustrated within a broad domestic economic diversification policy objective. The future growth prospects and challenges facing the Saudi petrochemical industry were also evaluated with respect to the evolving economic reform policies and Saudi international commitments. Potential implications for the petrochemical industry in North America were also identified, in terms of technology transfer and having Saudi Arabia secure the markets in order to meet its commitment to the World Trade Organization. tabs., figs
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)
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.
InfoTerra is an innovative market-derived EO-services concept with end-to-end products and service chains addressing end user information requirements in existing and new markets, with the advantage of a dedicated SAR satellite system TerraSAR (L+X-band) featuring high spatial and thematic resolution. The services will be provided from integrated value chains in a network with complementary partners, benefiting from most up-to-date and reliable image acquisition. The service development has been initiated in 1998 running in parallel to the TerraSAR space and ground system implementation. Infoterra, a new geo-information services company founded in 2001, implements the business concept. TerraSAR-X will be the first system element being available in 2006. The X-band SAR capability enables various applications, e.g. change detection to rationalize updating of cartographic databases; forest inventories, and de-/afforestation monitoring; crop stand density monitoring to support optimized fungicide application; land use monitoring in support of environmental control. A key challenge addressed in the exploitation development is the largely automated and quality controlled large area processing and feature extraction. The high resolution, multi-polarization, and multi-mode TerraSAR-X data source will considerably improve the short-term event observation from space. Reception of data via dedicated ground stations of customers or partners will also be offered.
Dialdin Osman; Elsaudi Mohammed
We examine dividend policy in a unique environment in Saudi Arabia, where (1) firms distribute almost 100% of their profits in dividends, (2) firms are highly levered mainly through bank loans, and (3) there are no income or capital gains taxes. Some common factors that affect dividend policy of both financial and non-financial firms, we found some factors that affect only non-financial firms. In particular, the common factors are profitability, size, and business risk. Government ownership, ...
This paper reviews the development of alliances to help develop the Terra Nova oil and gas field in the offshore Atlantic areas of Canada. Largely attributed to BP, the strategic alliance concept got its start in the North Sea and on the North Slope of Alaska. BP saw it as the best way to take advantage of economy-of-scale, mitigate risk, and achieve outsourcing goals while retaining their core competencies. This paper reviews the methods of developing the alliances, the developing of a development plan for the Terra Nova field, and how the alliance plans to maximize the profittability of the operation for all involved
Wolfe, Robert E.; Ramapriyan, Hampapuram K.
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.
Saleh, Mahmoud Abdullah
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)
Welch, James R.
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.
Full Text Available ULF geomagnetic field measurements in Antarctica are a very important tool for better understanding the dynamics of the Earths 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
Kugler, T.; Ruggles, S.; Fitch, C. A.; Clark, P. D.; Sobek, M.; Van Riper, D.
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
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
J. Romano Gallo
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
Russell, Patrick S.; Head, James W.; Hecht, Michael H.
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).
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)
The Grand Bank Alliance of Companies, which includes Brown and Root and Agra Industries, Haliburton Energy Services, Doris Engineering, FMC Corporation and PCL Constructors, have been awarded the primary fabrication contract by Petro-Canada to build a floating production and storage vessel for the Terra Nova oil project. The total pre-production costs are estimated at $1.6 billion; the first oil is scheduled for 1999. The contract involves construction of a double-hulled floating production, storage and offloading vessel, designed to process up to 150,000 barrels of crude per day, and storing up to one million barrels. In addition to Terra Nova, Brown and Root and Agra also have project management contracts building infrastructure for Sable Island natural gas
The mountain belts of Ishtar Terra and the surrounding tesserae are interpreted as compressional regions. The gravity and surface topography of western Ishtar Terra suggest a thick crust of 60-110 km that results from crustal thickening through tectonic processes. Underthrusting was proposed for the regions along Danu Montes and Itzpapalotl Tessera. Crustal thickening was suggested for the entire Ishtar Terra. In this study, three lithospheric models with total thicknesses of 40.75 and 120 km and initial crustal thicknesses of 3.9 and 18 km are examined. These models could be produced by partial melting and chemical differentiation in the upper mantle of a colder, an Earth-like, and a hotter Venus having temperatures of respectively 1300 C, 1400 C, and 1500 C at the base of their thermal boundary layers associated with mantle convection. The effects of basalt-granulite-eclogite transformation (BGET) on the surface topography of a thickening basaltic crust is investigated adopting the experimental phase diagram and density variations through the phase transformation.
Hendricks, Vincent Fella; Hendricks, Elbert
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...
Hicham Benjelloun; Abdulkader M.A. Abdullah
Purpose – The purpose of this paper is to investigate how best to diversify in Saudi Arabia's stock market. Design/methodology/approach – The analysis proceeds as follows: first, repeated sampling with replacement from a sample of 62 actual companies' monthly stock returns from January 2001 to June 2006 is used to simulate the performance of various portfolio sizes; second, a modified Statman diversification model is used to evaluate the performance of index funds in Saudi Arabia and thus ass...
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
Duwais, Abdul-Aziz M.
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 ...
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
Browning, John; Rosen, Ted
Terra firma-forme dermatosis is a cutaneous discoloration resembling dirt, hence the clinical name. The dyschromia cannot be removed with routine soap and water washing, but can be eliminated by rubbing with isopropyl alcohol. Although the condition poses no serious medical threat, it is cosmetically distressing. Our experience is that this entity is much more frequent that might be expected when considering the paucity of reports in the readily available medical literature. We chronicle a series of cases to highlight occurrence in widely divergent demographic groups and long duration of remission following appropriate topical intervention. The cause remains unknown. PMID:16150223
Chiara Tangari, Anna; Marinangeli, Lucia; Piluso, Eugenio; Pompilio, Loredana; Scarciglia, Fabio
Clay minerals, such as Fe/Mg smectite and Al-rich phyllosilicates (i.e., montmorillonite and kaolinite) were detected in the last years on Mars by numerous missions[1,2]. These minerals can be formed by fluid/rock interaction. Therefore, their study may provide important information on the climatic conditions and consequent habitability of the Martian surface. In this work we compare the mineralogy observed with CRISM data in the eastern part of Valles Marineris (Coprates-Ganges-Capri-Eos Chasmata), Margaritifer Terra and Margaritifer Chaos regions, with soils sampled on the Etna volcano (Sicily) and Cerviero Mount (Calabria, Southern Italy). We use an integrated approach of remote sensing coupled with pedological, petrographical and mineralogical investigations. Our purpose, here, is to find possible analogies between some Andosols developed on the basaltic substrates of Etna and Cerviero Mount, and the Martian soils, based on their spectral response and formation processes. CRISM data show poor abundance of clay minerals, such as illite, smectite and montmorillonite, in the eastern part of Valles Marineris. On the contrary, these phases are widely exposed in the Margaritifer Terra and Margaritifer Chaos, where we detected allophone (poorly crystalline clay), vermiculite, chlorite and other phyllosilicates belonging to the smectite group, such as saponite and nontronite. The surrounding area shows dominant signatures of basaltic composition.Our preliminary analysis on terrestrial soil profiles, using X-ray diffraction analysis, shows similar characteristics to Mars in terms of bedrock composition and clay mineralogy. Etnean soils, formed from lavas and pyroclastics of various ages (from 12 ka to 122 BC)  show the presence of clay minerals, such as kaolinite and small amounts of illite. The Cerviero Mount soils, developed on pillow basalts of Maastrichtian-Paleocene ages  are composed of vermiculite, illite, chlorite and interstratified clays such as
Arvidson, Raymond E.
This document summarizes the work accomplished under NASA Grant NAG5-3870. Emphasis was put on the development of the FIDO rover, a prototype for the twin-Mers which will be operating on the surface of Mars in 2004, specifically the primary work was the analysis of FIDO field trials. The grantees also analyzed VIKING Lander 1 XRFS and Pathfinder APXS data. Results show that the Viking site chemistry is consistent with an andesite, and the Pathfinder site is consistent with a basaltic andesite. The grantees also worked to demonstrate the capability to simulate annealing methods to apply to the inversion of remote sensing data. They performed an initial analyses of Sojourner engineering telemetry and imaging data. They performed initial analyses of Viking Lander Stereo Images, and of Hematite deposits in Terra Meridiani. They also acquired and analyzed the New Goldstone radar data.
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".
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 ...
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...
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.
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.
Sabino De Gisi
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.
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.
Al Rawaf, Haya Saad; Simmons, Cyril
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)
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)
Anderson, R. C.; Dohm, J. M.; Robbins, S.; Schroeder, J.
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.
Barclay, Tom; Gray, Jim; Strand, Eric; Ekblad, Steve; Richter, Jeffrey
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...
Rino N. Tosello
Full Text Available Neste trabalho descreve-se um novo amostrador tubular, de percussão, especialmente desenvolvido para a amostragem freqüente do solo, em terras roxas, para fins de determinação de umidade e controle de irrigação. Um desenho detalhado do novo amostrador é apresentado, com tôdas as indicações necessárias para que as pessoas ou organizações interessadas possam mandar construir novos modelos, em qualquer oficina mecânica bem aparelhada.In this paper is described a new soil sampler, specially designed for use in sampling Brazilian purple-soil series, which is known to present very peculiar physical properties. The sampler was developed as a result of the need to sample the soil frequently, for the purpose of maintaining the soil water balance in irrigation experiments, carried on field plots. This basic method of controlling water application in such experiments is being extensively used by the Seção de Irrigação, of the Instituto Agronômico. Detailed drawings ond some pictures are shown to allow interested persons or organizations, facing similar problems, to have models of the new sampler built in any good machine shop. The new sampler is very similar in its general characteristics to Veihmeyer's soil sampling tube, and was developed after the failure of this last sampler to operate properly in Brazilian purple-soils
Al-Goosi, Adbullah I.
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...
Bishop, Janice L.; Lane, Melissa D.; Dyar, M. Darby; Brown, Adrian J.
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 . 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 . 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 . 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.
Alkhareif Ryadh M.
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.
F. R. Pazheri
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.
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.)
Eriksen, Jonas Nogel; Kababo, Anas Yoseph; Madsen, Signe Røskva; Petersen, Asger Bagge
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...
Malik F. Saleh; Muneer Abbad; Mohammed Al-Shehri
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...
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
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
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.
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
Most of the Saudi desalination plants are of the multistage flash (MSF) type. These plants are often constructed as a dual purpose installation, producing power and water. MSF plants are considered to be energy intensive, where the energy cost is a major controlling parameter in the overall cost of desalination. Oil price fluctuations affect the cost of desalted water significantly. On the other hand, nuclear power offers price stability in the long term. Nuclear powered desalination provides long term availability of indigenous fuel, as well as long term fuel price stability. It has a minimum environmental impact if compared with other conventional desalination processes. The operational expenses of nuclear desalination are far lower than those of conventional plants. implementation of nuclear desalination in Saudi Arabia is essential where large water requirements exist. The CANDU PHWR is the appropriate type of nuclear reactor for Saudi Arabia. A hybrid reverse osmosis/MSF CANDU PHWR is the candidate system for applying dual purpose nuclear desalination plants in Saudi Arabia. (author)
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
Sayer, A. M.; Hsu, N. C.; Bettenhausen, C.; Jeong, M.-J.; Meister, G.
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.
Papers about Mars and Mars exploration are presented, covering topics such as Martian history, geology, volcanism, channels, moons, atmosphere, meteorology, water on the planet, and the possibility of life. The unmanned exploration of Mars is discussed, including the Phobos Mission, the Mars Observer, the Mars Aeronomy Observer, the seismic network, Mars sample return missions, and the Mars Ball, an inflatable-sectored-tire rover concept. Issues dealing with manned exploration of Mars are examined, such as the reasons for exploring Mars, mission scenarios, a transportation system for routine visits, technologies for Mars expeditions, the human factors for Mars missions, life support systems, living and working on Mars, and the report of the National Commission on Space
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…
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.
Devide, Antonio Carlos Pries
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).
Abdel-Razek, Moheb M; Fathy, Hanan
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. PMID:26632811
Maria Del Loreto Meix
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...
Because no previous studies have addressed the issue, we describe clinical characteristics and surgical outcome of patients with rhegmatogenous retinal detachment (RRD) in a pediatric population of the Eastern province of Saudi Arabia. We conducted a retrospective review of all consecutive cases of pediatric RRD (0-18 years) patients presenting at Dhahran Eye Specialist Hospital, a tertiary care hospital, in the Eastern Province of Saudi Arabia over a period of 3 years. Twenty patients were included in the study, accounting for 9.4% of all retinal detachment surgery cases performed over a period of 3 years (January 2006 to December 2008). The median age was 11.0 years, (range, birth to 18 years). Trauma, (45%) myopia/vitreoretinal degeneration (10%) and prior ocular surgery (25%) were significant risk factors for RRD. Proliferative vitreoretinopathy (PVR) more than grade C was present in 14/20 (70%) of cases. Most patients (15/20, 75%) were treated with pars plana vitrectomy and placement of an encircling buckle, while silicone oil or gas was used as tamponade in 13/20 (65%) patients. Surgery was successful in 17/20 (85%) cases in achieving retinal re-attachment. Visual acuity improved significantly following surgery (Mean preop 2.146 LogMAR, Mean postop 1.497 LogMAR) ( P= .014). Longer duration of RRD ( P =.007) and macular involvement ( P =.05) were associated with worse anatomical outcomes following surgery. Pediatric RRD in the Eastern province is often associated with predisposing pathology. Surgery is successful in achieving anatomical reattachment of the retina in a majority of cases with improvement of visual acuity. (author)
Full Text Available Background and Objectives: Because no previous studies have addressed the issue, we describe clinical characteristics and surgical outcome of patients with rhegmatogenous retinal detachment (RRD in a pediatric population of the Eastern province of Saudi Arabia. Patients and Methods: We conducted a retrospective review of all consecutive cases of pediatric RRD (0-18 years patients presenting at Dhahran Eye Specialist Hospital, a tertiary care hospital, in the Eastern Province of Saudi Arabia over a period of 3 years. Results: Twenty patients were included in the study, accounting for 9.4% of all retinal detachment surgery cases performed over a period of 3 years (January 2006 to December 2008. The median age was 11.0 years, (range, birth to 18 years. Trauma, (45% myopia/vitreoretinal degeneration (10% and prior ocular surgery (25% were significant risk factors for RRD. Proliferative vitreoretinopathy (PVR more than grade C was present in 14/20 (70% of cases. Most patients (15/20, 75% were treated with pars plana vitrectomy and placement of an encircling buckle, while silicone oil or gas was used as tamponade in 13/20 (65% patients. Surgery was successful in 17/20 (85% cases in achieving retinal re-attachment. Visual acuity improved significantly following surgery (Mean preop 2.146 LogMAR, Mean postop 1.497 LogMAR ( P= .014. Longer duration of RRD ( P =.007 and macular involvement ( P =.05 were associated with worse anatomical outcomes following surgery. Conclusion: Pediatric RRD in the Eastern province is often associated with predisposing pathology. Surgery is successful in achieving anatomical reattachment of the retina in a majority of cases with improvement of visual acuity.
Abdulrazzak, Mohammed J.; Khan, Muhammad Z. A.
Domestic water conservation in arid climates can result in efficient utilization of existing water supplies. The impacts of conservation measures such as the installation of water-saving devices, water metering and pricing schemes, water rationing and public awareness programs, strict plumbing codes, penalties for wasting water, programs designed to reduce leakage from public water lines and within the home, water-efficient landscaping, economic and ethical incentives are addressed in detail. Cost savings in arid climates, with particular reference to Saudi Arabia, in relation to some conservation techniques, are presented. Water conservation technology and tentative demonstration and implementation of water conservation programs are discussed.
The new economic trends of Saudi Arabia are detailed in this article. This country can take an important place on the world petroleum market in the future; he has the quarter of world petroleum reserves, and is determined to keep its place of first petroleum exporter. New developments projects are arising: electric power, telecommunications, civil aviation, seawater desalination. In terms of financing, as the state cannot finance all these new projects, new means are used: privatisation, BOT (build-operate-transfer) contracts, and offset programs. (N.C.)
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.
Garavís, M.; Bocanegra, Rebeca; Herrero-Galán, E.; González, Carlos; Villasante, Alfredo; Arias-González, J. R.
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.
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
Kaitseväe juhataja kindralmajor Riho Terras kinnitas NATO sõjalise komitee istungil Brüsselis liitlasriikidele, et Eesti on valmis osalema Afganistanis väljaõppe- ja toetusmissioonil "Resolute Support" pärast 2014. aastat, mil seal lõpeb rahvusvaheliste julgeolekutagamisjõudude sõjaline missioon
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
Compana, J. M.; Leon-Reina, L.; Aranda, M. A. G.
Terra Sigillata was a Roman pottery, which was also produced in several workshops in Hispania. Two known workshops at Granada (Cartuja and Carmen de la Muralla, or Albayzin) are known to have produced both typical Terra Sigillata and low-gloss coating related pottery. Potsherds from these workshops have been thoroughly studied from an archaeological approach, but not by analytical chemistry techniques. Here, we report a full characterization of nine selected samples from these workshops and also a tenth sample, Terra Sigillata made in the Gaul, for comparison. The pastes characterization includes elemental analysis from XRF and quantitative mineralogical analysis by Rietveld analysis of XRPD data. Cluster analysis to both types of data has been carried out. SEM-EDX and GI-XRPD have been used to characterize the slips of the pottery. The elemental analysis results for the pastes suggest that terra sigillata potsherds from both workshops were likely made from the same clay, different to that used to make the low-gloss coating pottery. The firing temperatures have been estimated from the phase assemblages being about 900-950 degree centigrade for the Granada sigillata. (Author)
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
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
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 ...
To assess the prevalence and characteristics of medication errors (ME) in patients admitted to King Fahd University Hospital, Alkhobar, Kingdom of Saudi Arabia. Medication errors are documented by the nurses and physicians standard reporting forms (Hospital Based Incident Report). The study was carried out in King Fahd University Hospital, Alkhobar, Kingdom of Saudi Arabia and all the incident reports were collected during the period from January 2008 to December 2009. The incident reports were analyzed for age, gender, nationality, nursing unit, and time where ME was reported. The data were analyzed and the statistical significance differences between groups were determined by Student's t-test, and p-values of <0.05 using confidence interval of 95% were considered significant. There were 38 ME reported for the study period. The youngest patient was 5 days and the oldest 70 years. There were 31 Saudis, and 7 non-Saudi patients involved. The most common error was missed medication, which was seen in 15 (39.5%) patients. Over 15 (39.5%) of errors occurred in 2 units (pediatric medicine, and obstetrics and gynecology). Nineteen (50%) of the errors occurred during the 3-11 pm shift. Our study shows that the prevalence of ME in our institution is low, in comparison with the world literature. This could be due to under reporting of the errors, and we believe that ME reporting should be made less punitive so that ME can be studied and preventive measures implemented (Author).
The objective of this study was to identify various stress factors affecting dentists and to evaluate their stress manifestations and stress management. A questionnaire was distributed among dentists residing in Jeddah, Saudi Arabia. The questionnaire classified stress factors into professional, patient-related, dental procedure-related, and office management factors. Sign and symptoms of stress manifestations and management were also evaluated. The sample included 80 females and 75 males, with 47% of them below the age of 30 years. Out of the total sample, the largest percentage (60.6%) were general practitioners, 47.7% had experience of less than 5 years and 32.2% had 11 years of experience. The highest mean scores of stress were related to professional factors and dental procedure-related factors. Among those, the main significant factors that caused stress in the surveyed sample were lack of time in relation to workload (76.1%), limited visibility and accessibility (67.7%). The most common manifestations of stress were nervousness (95%), musculoskeletal fatigue (72%) and anger (58%). Dentists predominantly managed their stress by praying and reading holy books (80%) and by spending time alone (75%) or with family and friends (70%). The most prevalent and significant causes of stress among dentists working in Jeddah, Saudi Arabia were professional in nature. Stress has been manifested by nervousness and musculoskeletal problem and was mainly managed by praying and spending time alone or with family and friends. (author)
de Vera, Jean-Pierre Paul; Lorek, Andreas; Koncz, Alexander; Billi, Daniela; Baqué, Mickael; Leya, Thomas; Brown, Sarah; Cockell, Charles
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.
... universities. Billions more are going toward ultra-modern mega-commerce and tourism projects, and the country's... architecture, engineering, design and construction firms. Saudi Arabia's transport sector--including...
Al Mohandis, Ahmed A. [احمد عبد القادر المهندس
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. ...
Abeer Abdullah Al Saud; Muhammad Rahatullah Khan (Rahatullah, M, K.,)
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...
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...
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 q...
Alosaimi, Fahad D; Alyahya, Haifa; Alshahwan, Hatem; Mahyijari, Nawal Al; Shaffi A Shaik
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....
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.
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...
Chang, S.; van der Lee, S.
The three-dimensional S-velocity structure beneath Arabia and East Africa is estimated down to the lower mantle to investigate vertical and horizontal extension of low-velocity anomalies that bear out the presence of mantle plumes and their flows beneath lithosphere. We estimated this model through joint inversion of teleseismic S- and SKS-arrival times, regional S- and Rayleigh waveform fits, fundamental-mode Rayleigh-wave group velocities, and independent Moho constraints from receiver functions, reflection/refraction profiles, and gravity measurements. With the unprecedented resolution in our S-velocity model, we found different flow patterns of hot materials upwelling beneath Afar beneath the Red Sea and the Gulf of Aden. While the low-velocity anomaly from Afar is well confined beneath the Gulf of Aden, inferring mantle flow along the gulf, N-S channel of low velocity is found beneath Arabia, not along the Red Sea. The Afar plume is distinctively separate from the Kenya plume, showing its origin in the lower mantle beneath southwestern Arabia. We identified another low-velocity extension to the lower mantle beneath Jordan and northern Arabia, which is thought to have caused volcanism in Jordan, northern Arabia, and possibly southern Turkey. Comparing locations of mantle plumes from the joint inversion with fast axes of shear-wave splitting, we confirmed horizontal plume flow from Afar in NS direction beneath Arabia and in NE-SW direction beneath Ethiopia as a likely cause of the observed seismic anisotropy.
Mansour Saleh AlYami
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.
Kumar, P. Senthil; Head, James W., III
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.
Vorderbruegge, R. W.; Head, James W.
Previous analyses have recognized several styles and orientations of compressional deformation, crustal convergence, and crustal thickening in Eastern Ishtar Terra. An east to west sense of crustal convergence through small scale folding, thrusting, and buckling is reflected in the high topography and ridge-and-valley morphology of Maxwell Montes and the adjacent portion of Fortuna Tessera. This east to west convergence was accompanied by up to 1000 km of lateral motion and large scale strike-slip faulting within two converging shear zones which has resulted in the present morphology of Maxwell Montes. A more northeast to southwest sense of convergence through large scale buckling and imbrication is reflected in large, northwest-trending scarps along the entire northern boundary of Ishtar Terra, with up to 2 km of relief present at many of the scarps. It was previously suggested that both styles of compression have occurred at the expense of pre-existing tessera regions which have then been overprinted by the latest convergence event. The difference in style is attributed mostly to differences in the properties of the crust converging with the tessera blocks. If one, presumably thick, tessera block converges with another tessera region, then the widespread, distributed style of deformation occurs, as observed in western Fortuna Tessera. However, if relatively thin crust (such as suggested for the North Polar Plains converges with thicker tessera regions, then localized deformation occurs, as reflected in the scarps along Northern Ishtar Terra. The purpose is to identify the types of features observed in Eastern Ishtar Terra. Their potential temporal and spatial relationships, is described, possible origins for them is suggested, and how the interpretation of some of these features has led to the multiple-style tectonic evolution model described is shown.
Previous analyses have recognized several styles and orientations of compressional deformation, crustal convergence, and crustal thickening in Eastern Ishtar Terra. An east to west sense of crustal convergence through small scale folding, thrusting, and buckling is reflected in the high topography and ridge-and-valley morphology of Maxwell Montes and the adjacent portion of Fortuna Tessera. This east to west convergence was accompanied by up to 1000 km of lateral motion and large scale strike-slip faulting within two converging shear zones which has resulted in the present morphology of Maxwell Montes. A more northeast to southwest sense of convergence through large scale buckling and imbrication is reflected in large, northwest-trending scarps along the entire northern boundary of Ishtar Terra, with up to 2 km of relief present at many of the scarps. It was previously suggested that both styles of compression have occurred at the expense of pre-existing tessera regions which have then been overprinted by the latest convergence event. The difference in style is attributed mostly to differences in the properties of the crust converging with the tessera blocks. If one, presumably thick, tessera block converges with another tessera region, then the widespread, distributed style of deformation occurs, as observed in western Fortuna Tessera. However, if relatively thin crust such as suggested for the North Polar Plains converges with thicker tessera regions, then localized deformation occurs, as reflected in the scarps along Northern Ishtar Terra. The purpose is to identify the types of features observed in Eastern Ishtar Terra. Their potential temporal and spatial relationships, is described, possible origins for them is suggested, and how the interpretation of some of these features has led to the multiple-style tectonic evolution model described is shown
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.
Sun, Junqiang; Xiong, Xiaoxiong; Madhavan, Sriharsha; Wenny, Brian
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.
Maria Del Loreto Meix
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.
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...
Winski, Richard; Bose, Dave; Komar, David R.; Samareh, Jamshid
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.
Kumar, P. Senthil; Head, James W.
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.
Parteli, Eric J R; Herrmann, Hans J
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
Parteli, Eric J. R.; Herrmann, Hans J.
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.
Li, Fuk K.
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.
AlGhamdi, Rayed; Drew, Steve; Al-Ghaith, Waleed
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...
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 ...
Durn, Goran; Ćorić, Radica; Tadej, Neven; Barudžija, Uroš; Rubinić, Vedran; Husnjak, Stjepan
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...
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 ...
This chart illustrates the variation in available solar power for each of NASA's twin Mars Exploration Rovers over the course of approximately two Mars years. Two factors affect the amount of available power: the tilt of Mars' axis and the eccentricity of the Mars' orbit about the sun. The horizontal scale is the number of Martian days (sols) after the Jan. 4, 2004, (Universal Time) landing of Spirit at Mars' Gusev Crater. The vertical scale on the right indicates the amount of available solar power as a ratio of the amount available at the equator when Mars is closest to the sun (perihelion). The red line indicates power availability at Spirit's landing site (Gusev). The blue line indicates power availability at Opportunity's landing site (Meridiani). The vertical scale on the right applies to the dotted line, indicating the latitude north or south of Mars' equator where the noon sun is overhead at different times of the Martian year.
Michelsen, Nils; Reshid, Mustefa; Siebert, Christian; Schulz, Stephan; Rausch, Randolf; Knöller, Kay; Weise, Stephan; Al-Saud, Mohammed; Schüth, Christoph
Arid countries like Saudi Arabia often depend on fossil groundwater. Hence, thorough studies of the available resources are crucial. In the course of such investigations, analyses of δ18O and δD are frequently applied to constrain the provenance of the waters and to reconstruct the (paleo)climatic conditions during their recharge. Yet, to be able to evaluate the isotopic signature of the groundwater, one also has to know the isotopic composition of current precipitation. Although a few rain water analyses are available for Central Saudi Arabia in the literature - mostly in unpublished consultant reports - a Local Meteoric Water Line has never been established. To complement the available data, 28 rain events occurring in Riyadh between 2009 and 2013 were studied for their stable isotope composition. Samples were collected as integral samples, i.e., they represent the entire precipitation event. Moreover, one event was sampled several times, aiming at an evaluation of intra-storm variability. During selected storms, a grab sample was taken for 3H analysis. The event samples showed δ18O and δD values scattering between -6.5 and +9.5 and between -30 and +50 ‰ V-SMOW, respectively. In the course of the event that was sequentially sampled, a proceeding isotopic depletion was observed with respect to both isotopes. The relatively large ranges of δ-values for 18O and D of approximately 7 and 38 ‰ V-SMOW highlight the general need for integral sampling. The obtained grab samples are characterized by moderate 3H concentrations of a few Tritium Units. Further results will be presented and discussed in view of associated weather data (e.g. rain amount and temperature) and the probable moisture sources derived from back-trajectories, which were calculated using HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory Model; Draxler & Rolph, 2003). References Draxler, R.R. & Rolph, G.D. (2013): HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory
Chang, Sung-Joon; Van der Lee, Suzan
We investigate mantle plumes and associated flow beneath the lithosphere by imaging the three-dimensional S-velocity structure beneath Arabia and East Africa. This image shows elongated vertical and horizontal low-velocity anomalies down to at least mid mantle depths. This three-dimensional S-velocity model is obtained through the joint inversion of teleseismic S- and SKS-arrival times, regional S- and Rayleigh waveform fits, fundamental-mode Rayleigh-wave group velocities, and independent Moho constraints from receiver functions, reflection/refraction profiles, and gravity measurements. In the resolved parts of our S-velocity model we find that the Afar plume is distinctly separate from the Kenya plume, showing the Afar plume's origin in the lower mantle beneath southwestern Arabia. We identify another quasi-vertical low-velocity anomaly beneath Jordan and northern Arabia which extends into the lower mantle and may be related to volcanism in Jordan, northern Arabia, and possibly southern Turkey. Comparing locations of mantle plumes from the joint inversion with fast axes of shear-wave splitting, we confirm horizontal mantle flow radially away from Afar. Low-velocity channels in our model support southwestward flow beneath Ethiopia, eastward flow beneath the Gulf of Aden, but not northwestwards beneath the entire Red Sea. Instead, northward mantle flow from Afar appears to be channeled beneath Arabia.
Mutlaq B. Alotaibi
Full Text Available The main purpose of this research was to gain an understanding of the adoption behavior of mobile computing in Saudi Arabia. In particular, it aimed to acquire new insight into mobile computing trends, specifically in Saudi Arabia, in order to develop hypotheses and formulate precise criteria for mobile computing evaluation. In order to achieve these aims, the researcher created a focus group by recruiting eight participants with solid background knowledge of usability engineering and mobile computing. The focus group proposed a four-phase process: determination, qualification, categorization and evaluation of the mobile computing applications developed by Saudi organizations. During the determination phase, two hundred and twenty seven (n=227 mobile applications were determined as having been developed by organizations in Saudi Arabia. During the qualification phase, one hundred and forty two (n=142 mobile applications were qualified. Within the categorization phase, the experts categorized only the qualified applications into a two-level categorization hierarchy. Finally, in the evaluation phase, the qualified applications were evaluated in terms of purpose, platform, visual appearance, content, organization and usability. The results herein revealed that 43% of the mobile applications in Saudi Arabia were M-Government applications, while 57% were M-Business applications. In addition, the study proposed a sample of thirty six (n=36 applications as having statistical significance from all of the mobile applications in Saudi Arabia.
Schmaltz, J. E.; Alarcon, C.; Boller, R. A.; Cechini, M. F.; Davies, D.; Fu, G.; Gunnoe, T.; Hall, J. R.; Huang, T.; Ilavajhala, S.; Jackson, M.; King, J.; McGann, M.; Murphy, K. J.; Roberts, J. T.; Thompson, C. K.; Ye, G.
The instruments onboard the Terra spacecraft were designed for long-term Earth science research but not long after launch it became apparent that this data and imagery could be made available in near real-time for applications users. During the year 2000 fire season in the western United States, the US Forest Service approached NASA with a request to expedite MODIS fire detections. The Rapid Response system was created to generate fire detections as well as true color imagery in both swath and geo-referenced formats. This imagery was used by a wide variety of applications, such as NASA's AERONET program, the USDA Foreign Agricultural Service, Antarctic resupply shipping, flood mapping for relief agencies, Deepwater Horizon monitoring, volcanic ash monitoring, as well as print, televised, and Internet media. From 2004, the University of Maryland's Web Fire Mapper helped distribute fire detection information in a variety of formats. However, the applications community expressed the need for near-real time access to the underlying data. This requirement led to the development of the Land Atmosphere Near real-time Capability for EOS (Earth Observing System) (LANCE) in 2009. To achieve the latency requirements, many components of the EOS satellite operations, ground and science processing systems had to be made more efficient. In addition, products that require ancillary data were modified to use alternate inputs. Forty Terra MODIS data products are currently available from LANCE. LANCE also includes data from other instruments including AIRS, AMSR-E, MLS, and OMI. To help near-real time users navigate this large data offering, a new imagery service was begun in 2011 - Global Imagery Browse Services (GIBS). This service provides very responsive viewing using the Web Map Tile Service protocol. These programs will continue to support and expand the use of Terra data for near-real time applications well into the future.
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...
Abeer Abdullah Al Saud
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.
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.
Ziad A. Memish
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.
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.
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
Landis, Geoffrey A.; Kerslake, Thomas W.; Jenkins, Phillip P.; Scheiman, David A.
NASA missions to Mars, both robotic and human, rely on solar arrays for the primary power system. Mars presents a number of challenges for solar power system operation, including a dusty atmosphere which modifies the spectrum and intensity of the incident solar illumination as a function of time of day, degradation of the array performance by dust deposition, and low temperature operation. The environmental challenges to Mars solar array operation will be discussed and test results of solar cell technology operating under Mars conditions will be presented, along with modeling of solar cell performance under Mars conditions. The design implications for advanced solar arrays for future Mars missions is discussed, and an example case, a Martian polar rover, are analyzed.
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...
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…
Budney, C. J.; Miller, S. L.; Cutts, J. A.
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.
Sohus, A. M.; Viotti, M. A.; de Jong, E. M.
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.
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.
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.
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...
Abdel Gader Abdel Galil
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.
Mckay, Christopher P. (Editor); Davis, Wanda, L. (Editor)
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.
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
... 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 Caithness Dixie Valley, LLC) (Terra-Gen) pursuant to section 206 of the Federal Power Act, and 18 CFR...
Abu-Elmagd, Muhammad; Assidi, Mourad; Schulten, Hans-Juergen; Dallol, Ashraf; Pushparaj, Peter; Ahmed, Farid; Scherer, Stephen W; Al-Qahtani, Mohammed
The biomedical research sector in Saudi Arabia has recently received special attention from the government, which is currently supporting research aimed at improving the understanding and treatment of common diseases afflicting Saudi Arabian society. To build capacity for research and training, a number of centres of excellence were established in different areas of the country. Among these, is the Centre of Excellence in Genomic Medicine Research (CEGMR) at King Abdulaziz University, Jeddah, with its internationally ranked and highly productive team performing translational research in the area of individualized medicine. Here, we present a panorama of the recent trends in different areas of biomedical research in Saudi Arabia drawing from our vision of where genomics will have maximal impact in the Kingdom of Saudi Arabia. We describe advances in a number of research areas including; congenital malformations, infertility, consanguinity and pre-implantation genetic diagnosis, cancer and genomic classifications in Saudi Arabia, epigenetic explanations of idiopathic disease, and pharmacogenomics and personalized medicine. We conclude that CEGMR will continue to play a pivotal role in advances in the field of genomics and research in this area is facing a number of challenges including generating high quality control data from Saudi population and policies for using these data need to comply with the international set up. PMID:25951871
Priehodová, E.; Abdelsawy, A.; Heyer, E.; Černý, Viktor
Roč. 86, č. 1 (2014), s. 7-18. ISSN 0018-7143 R&D Projects: GA ČR GA13-37998S Institutional support: RVO:67985912 Keywords : lactase persistence * Arabia * Africa * migration Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 0.853, year: 2014
Alameen, Lubna; Male, Trevor; Palaiologou, Ioanna
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…
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
Payne, Mark; Almansour, Maram
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…
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
Fernandes, V.; Triska, P.; Pereira, J. B.; Alshamali, F.; Rito, T.; Machado, A.; Fajkošová, Zuzana; Cavadas, B.; Černý, Viktor; Soares, P.; Richards, M. B.; Pereira, L.
Roč. 10, č. 3 (2015), e0118625. E-ISSN 1932-6203 R&D Projects: GA ČR GA13-37998S Institutional support: RVO:67985912 Keywords : Arabia * archaeogenetics * migrations Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 3.234, year: 2014
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
Borg, Simon; Alshumaimeri, Yousif
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…
Alakeel, Ali M.
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…
Spicer, Richard G.
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)
King, Elizabeth J.
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)
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)
... Information and Communication Technologies (ICT) trade mission to the Kingdom of Saudi Arabia, April 2-5, 2011... introduce suppliers of information technology (IT) and communication products and services to potential..., estimated at $3.7 billion in 2010. The Communication and Information Technology Commission (CITC), the......
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
Dubinin, Eduard; Fraenz, Markus; Andrews, Dave; Morgan, Dave
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.
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
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
The aim of this study is to assess the clinical presentation of 23 patients with subacute thyroiditis (SAT) and the diagnostic value of radionuclear scan. This is a cohort study, which consists of 23 patients with a suspected diagnosis of subacute thyroiditis. The study was carried out in the Endocrinology Clinic, King Abdul-Aziz University Hospital, Jeddah, Kingdom of Saudi Arabia between July 2002 and July 2004. Medical charts including age, gender, clinical presentation, systemic symptoms and clinical examination of the thyroid gland were reviewed. Laboratory data included white blood count and its differential count, erythrocyte sedimentation rate (ESR), thyroid function test and thyroid antibodies. The radionuclear scan results were also noted. The mode of therapy provided to patients and the outcome of the treatment during a follow up period of 2 years was reported. Twenty-three adult patients with subacute thyroiditis (15 females and 8 males with a female to male ratio of 1.9:1) were reviewed over a 2-year period. The mean age was 35.8+9.2 years. Eighteen patients (78%) had an upper respiratory tract infection at the initial clinical presentation. Twenty patients (87%) visited an Ear, Nose and Throat specialist for sore throat and abnormal sensation in the throat at least 2 weeks before presentation to the endocrinologist. Two patients were admitted to a medical unit with a diagnosis of fever of unknown origin for 4 weeks. All patients had an elevated free thyroxine (35.7+19.8 pmol/L) and suppressed thyroid-stimulating hormone (TSH) (0.043+0.065IU). The radionuclear scan showed either no uptake at all in 12 patients or minimal uptake in 11 patients (0.32+0.55%). Eight patients (35%) received prednisolone therapy alone with an average dose of 30-40 mg daily for 7-8 days; 7 patients (30%) were treated with non-steroidal anti-inflammatory drugs (NSAIDs) only. Eight (35%) patients were treated with both NSAIDs and corticosteroids. Hypothyroidism, with elevated
During the course of a plant accident, a consistent understanding of the plant response is vital to support an accident manager's decision making process. One tool that can provide assistance to the plant staff in assessing conditions in the plant during accident conditions is the MAAP Accident Response System (MARS) software. During an accident, MARS utilizes the on-line data from the plant instrumentation to initialize the Modular Accident Analysis Program (MAAP) code. Once initialized, MARS tracks and characterizes the plant behavior through the use of integrated logic modules. These logic modules provide the user with important information about the status of systems and the possible cause of the accident. The MARS logic modules evaluate relevant available plant instrumentation and the observations of the operating staff using fuzzy logic. The fuzzy logic is applied to provide a transition between areas where one is absolutely sure that a situation has not occurred to a condition where one is absolutely certain that a situation has occurred. One example of the use of logic modules in MARS is illustrated by that used to assess if a steam generator tube rupture (SGTR) event has occurred. Each piece of relevant plant data is evaluated to determine if it is consistent with the symptoms of a SGTR. Each of the evaluations for the individual plant instruments and the operating staff observations are assembled to determine an overall confidence which characterizes the likelihood that a SGTR is occurring. Additional MARS logic modules are used to determine confidence levels for other types of accident events. The conclusions arrived at by each individual logic module are expressed as confidence levels. The logic module confidence levels can be graphically displayed using the MARS Graphical Users Interface (GUI), to indicate the confidence level MARS has assessed for each accident type. The GUI shows the identification of the possible accident types, but is not limited
Xiong, X.; Salomonson, V.
The first MODIS instrument, launched on-board the NASA EOS Terra spacecraft in December 1999, has successfully operated for nearly 15 years. MODIS observations have significantly contributed to the studies of many geophysical parameters of the earth's system and its changes over time. Dedicated effort made by the MODIS Characterization Support Team (MCST) to constantly monitor instrument operation, to calibrate changes in sensor response, to derive and update sensor calibration parameters, and to maintain and improve calibration algorithms has played an extremely important role to assure the quality of MODIS data products. MODIS was developed with overall improvements over its heritage sensors. Its observations are made in 36 spectral bands, covering wavelengths from visible to long-wave infrared. The reflective solar bands (1-19 and 26) are calibrated on-orbit 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 tracked by a spectroradiometric calibration assembly (SRCA). This paper provides an overview of Terra MODIS on-orbit operation and calibration activities implemented from launch to present and the status of instrument health and functions. It demonstrates sensor on-orbit performance derived from its telemetry, on-board calibrators (OBC), and lunar observations. Also discussed in this paper are changes in sensor characteristics, corrections applied to maintain level 1B data quality, various challenging issues, and future improvements.
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
Irwin, Patrick G. J.; Calcutt, S.B.; P. L. Read; Bowles, N E; Lewis, S
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...
An evaluation is presented of the ramifications of the loss of contact with the Mars Observer spacecraft in August, 1993; the Observer constituted the first NASA mission to Mars in 17 years. It is noted that most, if not all of the scientists involved with the mission will have to find alternative employment within 6 months. The loss of the Observer will leave major questions concerning the geologic history of Mars, and its turbulent atmospheric circulation, unanswered. A detailed account of the discovery of the loss of communications, the unsuccessful steps taken to rectify the problem, and the financial losses incurred through the failure of the mission, are also given.
Devincenzi, D. L. (Editor); Marshall, J. R. (Editor); Andersen, D. (Editor)
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.
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...
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...
Al-maghrabi, T; Dennis, C.
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...
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...
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.
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...
High resolution images that help scientists fine tune the landing site for NASA's Mars Surveyor lander mission are shown. These images reveal a smooth surface in the southern cratered highlands near the Nepenthes Mensae.
Anderson, D. L.
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.
A compilation of scientific knowledge about the planet Mars is provided. Information is divided into three categories: atmospheric data, surface data, and astrodynamic data. The discussion of atmospheric data includes the presentation of nine different models of the Mars atmosphere. Also discussed are Martian atmospheric constituents, winds, clouds, and solar irradiance. The great dust storms of Mars are presented. The section on Mars surface data provides an in-depth examination of the physical and chemical properties observed at the two Viking landing sites. Bulk densities, dielectric constants, and thermal inertias across the planet are then described and related back to those specific features found at the Viking landing sites. The astrodynamic materials provide the astronomical constants, time scales, and reference coordinate frames necessary to perform flightpath analysis, navigation design, and science observation design
Cavagna, G. A.; Willems, P. A.; Heglund, N. C.
Sometime in the near future humans may walk in the reduced gravity of Mars. Gravity plays an essential role in walking. On Earth, the body uses gravity to `fall forwards' at each step and then the forward speed is used to restore the initial height in a pendulum-like mechanism. When gravity is reduced, as on the Moon or Mars, the mechanism of walking must change. Here we investigate the mechanics of walking on Mars onboard an aircraft undergoing gravity-reducing flight profiles. The optimal walking speed on Mars will be 3.4 km h-1 (down from 5.5 km h-1 on Earth) and the work done per unit distance to move the centre of mass will be half that on Earth.
Almeida, Murilo P.; Parteli, Eric J. R.; José S. Andrade; Herrmann, Hans J.
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...
Albee, A. L.; Arvidson, R.E.; Palluconi, F. D.
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...
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.
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...
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...
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...
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...
Roeder, Brent W.; Fish, Robert C.
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.
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.
This paper reports on the prevalence of oral lichen planus among 4277 dental patients aged 18-73 years, seen in the Dental Department, King Fahad Central Hospital, Gizan, Saudi Arabia, between 1982 and 1987. Oral mucosal lesions, diagnosed as lichen planus, were clinically and histologically identified in 72 subjects (40 males and 32 females). The average age of the affected group was 49 years. No correlation was evident between lichen planus and tobacco habits in this study, nor was there any association with diabetes or hypertension. The average period of follow-up was 3.2 years, during which time 4 patients developed malignant transformation of their oral lesions. The prevalence of lichen planus in this study was 1.7%, which is higher than the prevalence figures reported earlier for this disease in Saudi Arabia. (author)
Al-Hajoj, Sahal; Varghese, Bright
Saudi Arabia is the third-largest Arab country with a moderate annual burden of tuberculosis. However, tuberculosis (TB) is among several infectious diseases that have not been brought under control, despite the government's considerable efforts. This is clearly evidenced by the ongoing transmission of several imported and indigenous clades of Mycobacterium tuberculosis. In addition, the country faces the threat from rising proportions of extrapulmonary TB, non-tuberculous mycobacterial infections, and drug resistance. Furthermore, the country falls behind the global targets set by World Health Organization for the success rate of TB treatment. The country needs more population-based research studies, centralized and easily accessible clinical data registries, and centralized research and diagnostic facilities. This review focused on the trends of mycobacterial infections and on future proposals to improve TB control measures in Saudi Arabia. PMID:25771458
Mansour, A A; Hassan, S A
We studied knowledge of nutritional needs during pregnancy and lactation in 150 pregnant Saudi women at three primary health care centers in Riyadh, Saudi Arabia. We used an interview schedule to collect data regarding the women's knowledge and to determine the effects of certain independent variables on the knowledge scores. Green et al.'s (1980) PRECEDE model provided the theoretical framework for the study. Descriptive statistics, t test, and chi-square methods were used to analyze the data. The majority of the women had poor nutrition knowledge scores, with no significant differences among the three centers. A positive relationship was found between knowledge score and educational level. Negative relationships were found between knowledge score and number of pregnancies, number of deliveries, and number of living children. The findings have several implications for efforts to improve the health status of women in Saudi Arabia. PMID:8002417
Gebhardt, S.; Huth, J.; Wehrmann, T.; Schettler, I.; Künzer, C.; Schmidt, M.; Dech, S.
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
Al Alwan, Ibrahim; Felimban, Naila; Altwaijri, Yasmin; Tamim, Hani; Al Mutair, Angham; Shoukri, Mohamed; Tamimi, Waleed
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...
International Monetary Fund
KEY ISSUES Context. Saudi Arabiaâ€™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 ...
Intakhab Alam Khan
The present paper attempts to explore the characteristics of an effective teacher of English. Some related factors such as qualification, attributes, roles, and professional ethics have also been dealt with. In Saudi Arabia, the teacher of English plays the most important role in the process of teaching/learning. There are so many factors such as L1 interference, parental attitude, home environment, schooling etc that are usually influential in the case of educational setting in general and E...
Mohamed A. Almannie
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 ...
Jamjoom, Ghazi A.; Azhar, Esam I.; Moujahid A. Kao; Radadi, Raja M.
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...
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 f...
Al-Kahtani, Safer H.; Sofian, Badr El-din E.
The purpose of this paper is to investigate the preference change in the demand for meat subject to random coefficients in Saudi Arabia. A Fortran 77 program has been designed to estimate the demand function for meat using Kalman filtering techniques and maximum likelihood approach. The initial values of the coefficient and covariance estimates are an essential prior information in the Kalman filtering techniques. Results provide substantial random coefficients in red meat, implying important...
Salem, G; Holm, S A; Fattah, R; Basset, S; Nasser, C
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
Saeed, Abdalla A.
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...
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 ...
Sherif, Sherin A.; Al-Kahtani, Safer H.
Managerial efficiency for broiler producers in Saudi Arabia is generally difficult to achieve. High investment costs coupled with relatively high average production costs and the consequent incompetent market prices, have resulted in projects either working at less than full capacity or being shut down completely. The aim here is to determine the most efficient production alternatives (actions) available to managers under business risk considerations. The ordinary stochastic dominance approac...
Mounir Belloumi; Atef Saad Alshehry
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...
Rajaa M. Milyani
The aerobic microbial skin flora of 40 healthy subjects living in Jeddah city (Saudi Arabia) was determined. Two age groups: children and adults; including males and females were investigated. Seven sites were studied: forehead, axilla, chest, groin, leg, toe web and anterior nares. The skin was sampled by rubbing the chosen site with a surfactant substance (Tween 80) moistened cotton swab which was dipped back in the surfactant container and the resulted suspension was agitated for one minut...
KKhodran H. Al-Zahrani and M. B. Baig
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...
Haifa Abdulaziz Al-Turki
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...
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...
Ginting, Grace Anastasia br
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....
Sitepu, Maria Atrina
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...
Extraterritorial ownership and control of sub-Saharan African land have a long and troubledhistory. This research investigates a much-studied practicethe recent enclosure of African landand resourcesbut asks a little-studied question: how are non-Africans reasserting terra nulliusnarratives of the past to justify the present transformation of African landscapes? The answersuggested here lies in a bulwark of de facto terra nullius claims couched in security needs of theglobal North and referen...
Antonio Porro; Sascha Feuerhahn; Joachim Lingner
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...
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
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. PMID:24823799
Allergenicity Prosopis juliflora pollen antigen has been reported fromonly a few countries, including the US, South Africa, India and Kuwait. Insome parts of Saudi Arabia, species of Prosopis have been introduced by themillions as roadside ornamentation. There appear to be four flowering seasonsduring which pollen grains float in all directions. However, the role ofProsopis pollen as the sensitizing and/or rhinitis in the Kingdom has neverbeen evaluated. A total of 473 allergic patients suffering from the bronchialasthma in four different geographical regions (Abha, Qassim, Hofuf, Gizan),and attending allergy clinics and chest disease centers of university andMinistry of Health hospitals in the region were tested for immediatehypersensitivity reaction to Prosopis Juliflora allergens. Airborne pollengrains at one center were also studied for one full year, using volumetricsampling techniques. A total of 76.1% patients in Qassim, 37.5% in Gizan, 29%in Abha and 11% in Hofuf reacted positively to Prosopis antigen. Multiplesensitivities to other pollen antigens were detected in all patients. Thelevel of airborne Prosopis pollen detected in Gizan exceeded 90 grains m ofair. In view of documented evidence of Prosopis pollen as a sensitizingfactor in Saudi Arabia has been confirmed. However the cause of elicitationof symptoms in many multiple sensitive patients, together with the questionof cross-reactivities, needs thorough and detailed investigation. In vitroconfirmation of all positive results is also required to incriminate Prosopisas one of the major allergens in parts of Saudi Arabia. (author)
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.
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
Madhavan, Sriharsha; Xiong, Xiaoxiong; Sun, Junqiang; Chiang, Kwofu; Wu, Aisheng
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.
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
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.
Bruck, Miguel; Lehner, Susanne
The main highlights of TerraSAR-X (TS-X) synthetic aperture radar (SAR) imagery are a higher resolution of up to 1 m, when compared to conventional C-band SAR data, and a reduction of nonlinear imaging effects of a moving target by lower platform altitude. Thus, ocean waves with wavelength TS-X particularly useful to observe coastal areas where complex bathymetry strongly impacts the approaching waves. TS-X images acquired in different coastal areas are presented, including three case studies at the German coast. Wave fields (significant wave height and peak wavelength) are derived from the TS-X imagery using the proposed XWAVE algorithm and compared not only to in situ buoy wave measurements but also to results of a high-resolution numerical wave model. The objective is to study the quality of significant wave height field estimation in the spatial domain in highly variable conditions, which are typically dominant in coastal areas. The results show that the empirical XWAVE algorithm allows estimating wave fields from TS-X data with high resolution, thus showing the spatial information on wave variations. Therefore, it is a new useful tool to characterize sea state in coastal areas by remote sensing.
During GANOVEX VII in 1992, kyanite was discovered in quartz veins on the southwest flank of Mt Levick, in the Deep Freeze Range, Terra Nova Bay, Antarctica. The quartz veins cut an isoclinally (D1) folded sequence of low-grade (Mu-Bt-Crd±And±St) pelitic schist with associated para-amphibolites, calc-silicates, and quartzites (Priestley Formation), which forms the western, steeply dipping to overturned limb of a D2, kilometric fold. The schists grade northeastwards into higher grade schists (Kfs-Sil-Crd) of the low-angle upper limb of the D2 fold, and thus the regional metamorphism postdates the fold. D3 southeast-verging folds lie on the upper limb. The kyanite crystals (up to 3.5 cm long) occur with paragonitic muscovite and minor plagioclase (An36. The quartz veins and saddle reefs are cleaved and boudinaged, but the kyanite shows only mild deformation suggesting late tectonic growth. There is no indication that the host schists entered the stability field of kyanite. The change in P-T conditions that promoted the growth of kyanite appears to have been transient and temporally insufficient to allow the country rocks to react. It is suggested that the action of the nearby Boomerang Thrust bringing older gneiss over the Priestley Formation schists could have generated the D3 folds and provided the necessary overpressure conditions for the kyanite to grow from the quartz vein fluids. (author). 23 refs., 5 figs., 1 tab
Luiz Marcelo Brandão Carneiro
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.
Zulipiye, Kaiyoumu; Balik Sanli, Fusun
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.
Full details of the Merit Appraisal and Recognition Scheme (MARS) are available via the HR Department’s homepage or directly on the Department’s MARS web page: https://cern.ch/hr-dept/ https://cern.ch/hr-eguide/mars/mars.asp You will find on these pages: MARS procedures including the MARS timetable for proposals and decisions; Regulations with links to the scheme’s statutory basis; Frequently Asked Questions; Useful documents with links to relevant documentation; e.g. mandate of the Senior Staff Advisory Committee (SSAC); Related links and contacts. HR Department Tel. 73566
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
Gupta, S.; Fawdon, P.; Grindrod, P. M.; Balme, M. R.; Hauber, E.; Warner, N. H.; Muller, J. P.
The identification of putative ancient deltaic sedimentary systems on Mars has been both exciting and controversial. Our excitement is elicted by the potential provided by deltas as evidence for standing bodies of water associated with the deltas, and the resulting implications for both the ancient climate of Mars and ancient habitability. The controversy stems from how confident can we be in the identification of ancient deltaic systems from orbital data, and how robust are our assertions about the habitability potential of such settings. Delta systems in particular are key astrobiological targets because at their distal toes fine-grained sediment (ie., clays) settle from suspension in a lower energy setting and they are commonly characterised by high rates of sedimentation. This leads to high preservation potential of biosignatures. Targeting of future Mars rovers to investigate deltaic landing sites requires better understanding of these issues to reduce exploration risk. In this presentation, we describe the key criteria that enable us to make robust interpretations of deltaic stratigraphy and constrain delta evolution for martian systems. In particular, the past 10 years has seen in a revolution in our process understanding of terrestrial delta systems through a combination of field, experimental and numerical modelling studies. Analysis of martian deltas has much to gain from these results. We go on to consider why deltaic systems offer potential as astrobiological target paleoenvironments. We use the exhumed delta system (Hypanis delta system) at the termination of Hypanis Vallis, 11.8°N, 314.96°E as a case example. This system, situated in Xanthe Terra, comprises layered sedimentary rocks with an overall multi-lobate geometry and associated inverted channel networks. The Hypanis 'delta' is a proposed landing site for the ExoMars rover and also for the NASA 2020 mission.
Ghulam, Ayman S.
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
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.
Russell, C. T
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 ...
Riebeek, H.; Chambers, L. H.; Yuen, K.; Herring, D.
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
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...
Curtis, S. A.; Ness, N. F.
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.
Meneses, Avelino de Freitas de
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. ...
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)
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 respondentsâ€™ 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.
Van Loef, J.; Schmets, A. J. M.
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 bewijs geleverd is over het bestaan van leven op Mars blijft echter een open vraag.
Albee, A. L.; Palluconi, D. F.
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...
Tanaka, Kenneth L.
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.
Cabrol, Nathalie A
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
Burns, Roger G.
The appearance of rusty iron-rich oxidized cappings over sulfide-bearing rocks on earth indicates that similar gossans may have formed on the surface of Mars. Electrochemical processes and thermodynamic relationships linking acidity to oxidation-reduction reactions between primary sulfide minerals and their oxidative weathering products present in the regolith of Mars are discussed. Remote-sensed visible spectra of the Martian surface are in keeping with the presence of poorly-crystalline FeOOH, jarosite, silica, and clay silicates found in gossans, while incompletely weathered pyrrhotite may represent the magnetic material observed in Martian regolith.
Johnstone, C. M.; McCombes, T.; Bahaj, A. S.;
/ 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...
Blanchard, Douglas P.
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.
<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
Full Text Available With a new era dawning with regard to access to space and an increase in the number of nations capable of reaching and exploiting space, the field of space law as a whole needs to be re-evaluated. One such area where current legal thinking needs to be examined is with regard to the property rights to objects in space. While it was sufficient in the past for governments to frown upon the institutions of ownership in outer space and leave many space-related issues unresolved, one would need to re-examine the current body of space-law and related international instruments in the light of the ability of private enterprises’ and other new players’ ability to partake in and commercially exploit space travel. This paper investigates whether property rights should be available to space-faring nations and individuals, as well as how these rights could be acquired. Also very important is how these rights could be limited or structured in such a way as not to unnecessarily interfere with the aims of current space law. Characteristics such as the impersonality, tangibility, independence, susceptibility to control, and the usefulness and value for mankind of an object in space will once again be of crucial importance when it is necessary to determine if it can be classified as an object with regard to which one can have property rights. This is discussed against the background of objects that are deemed to be res nullius (things belonging to nobody as well as the theory of terra nullius (land belonging to nobody.
Kim, Soo-Jin; Park, Joo-Hyeon; Lim, Jun-Muk; Ahn, Jae-Hyung; Anandham, Rangasamy; Weon, Hang-Yeon; Kwon, Soon-Wo
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
Van Loef, J.; Schmets, A.J.M.
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
Hauber, E.; Platz, T.; Le Deit, L.; van Gasselt, S.; Kinch, K.; Madsen, M. B.; Rosenberg, H.
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.
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
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
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.
Al-Alaiyan, Saleh; Alfaleh, Khalid M
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
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.
Mahmoud, Mahmoud Abdulrahman; Al-Zalabani, Abdulmohsen H; Bin Abdulrahman, Khalid A
In the last decade, public health (PH) has come to the frontlines in Saudi Arabia. The recent outbreak of a novel corona virus (MERS-CoV) highlighted the importance of PH services and the need for a competent PH workforce. The urgency and panic induced by infectious disease outbreaks explain the heightened interest. Decision makers' interest in public health was observed through a series of decisions, including creating a position for Deputy Minister for Public Health, changing the name of "Directorate of Primary Healthcare Centers" to "Directorate of Public Health" in all health regions and initiating a special scholarship program to prepare health administration professionals in collaboration with US-based universities. A distinguished group of PH leaders in Saudi Arabia was gathered in a structured workshop that was organized by the Al Imam Mohammad Ibn Saud Islamic University, college of medicine to discuss the current status and future needs of PH education in the Kingdom of Saudi Arabia. The workshop highlighted the need for PH education development and outlined the challenges ahead. The main challenges laid out by participants in the workshop were the development of an appropriate PH curriculum, appropriate training spots for practical placement, the development of research priorities for PH to satisfy the needs of PH programs and agencies, attracting the most qualified academic staff, the enrolment of highly motivated students and finally, the establishment of a quality assurance program to ensure the quality of PH education programs. The development of a framework for graduate competencies in PH was perceived to be a top priority. Moreover, setting a PH workforce surveillance system, building partnership between PH academic institutions and PH services providers, implementing national campaigns to explain what PH is about and illuminating the role of PH workers were also of utmost importance. PMID:26984034
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)
Moore, Jeffrey M.; Bullock, Mark A.; Stoker, Carol R.
Evaporites, particularly carbonates, nitrates, and sulfates, may be major sinks of volatiles scavenged from the martian atmosphere. Mars is thought to have once had a denser, warmer atmosphere that permitted the presence of liquid surface water. The conversion of atmospheric CO2 into carbonate is hypothesized to have degraded the martian climate to its present state of a generally subfreezing, desiccated desert. The rate for such a conversion under martian conditions is poorly known, so the time scale of climate degradation by this process cannot be easily evaluated. If some models are correct, carbonate formation may have been fast at geological time scales. The experiments of Booth and Kieffer also imply fast (10(exp 6) - 10(exp 7) yr) removal of the missing CO2 inventory, estimated to be 1 - 5 bar, by means of carbonate formation. The timing of formation of many of the fluvial features observed on Mars is, in large part, dependent on when and how fast the atmosphere changed. A knowledge of the rate at which carbonates and nitrates formed is also essential for assessing the probability that life, or its chemical precursors, could have developed on Mars. No previous experiments have quantitatively evaluated the rate of solution for a suite of mobile anions and cations from unaltered minerals and atmospheric gases into liquid water under Mars-like conditions. Such experiments are the focus of this task.
Almeida, Murilo P; Parteli, Eric J R; Andrade, José S; Herrmann, Hans J
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
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...
Mathew, K. J.; Marti, K.; Marty, B.
Fission Xe components due to Pu-244 decay in the early history of Mars have been identified in nakhlites; as in the case of ALH84001 and Chassigny the fission gas was assimilated into indigenous solar-type Xe. Additional information is contained in the original extended abstract.
Dindler, Christian; Eriksson, Eva; Iversen, Ole Sejer;
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...
Bin Abdulrahman, Khalid A; Tawfik, Bassel
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. PMID:26984027
B. H. Alharbi; M. J. Pasha; N. Tapper
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...
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...
The Ablah sedimentary succession represents a molasse basin in the Neo-Proterozoic Shield of Saudi Arabia. A rhyolite flow interbedded in the succession has been dated by the Pb/Pb method at 641± 1 Ma, indicating that the basin is a local expression of Panafrican tectonism in the south of the shield. Consequently, the Panafrican phase that has previously been described in the north can now be extrapolated to the south of the shield. This age determination also enables post-Panafrican events, which differ between the south and the north, to be analysed over the entire shield. (authors)
Al-Kadri HM; Madkhali A; Al-Kadi MT; Bakhsh H; Alruwaili NN; Tamim HM
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...
Teixeira, Rubenilson B.
Natal, capitale de l’état du Rio Grande Norte, Brésil, et Dakar, capitale du Sénégal, situées respectivement dans des points extrêmes de l’Amérique du Sud et de l’Afrique Occidentale, se trouvent dans la distance la plus courte entre les deux continents, séparés par l’Atlantique. Historiquement, ces sites urbains ont été stratégiques depuis les grandes navigations, et sont restés importants aux temps du développement moderne des voies de communications survenues avec la Révolution Industriell...
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
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.
Muggler, Cristine Carole; Rozenberg, Bianca; de Cássia Francisco, Talita; Gramacho de Oliveira, Elisa
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
Kim, Soo-Jin; Moon, Ji-Young; Hamada, Moriyuki; Tamura, Tomohiko; Weon, Hang-Yeon; Suzuki, Ken-ichiro; Kwon, Soon-Wo
A novel Gram-stain-positive, non-motile, rod-shaped bacterium, designated 5GHs34-4(T), was isolated from greenhouse soil in Yongin, Republic of Korea. Growth occurred in the temperature range of 10-37 °C (optimum 28-30 °C) and at pH 5.0-9.0 (optimum pH 7.0). It can tolerate up to 3 % (w/v) NaCl. The strain showed 16S rRNA gene sequence similarity levels of 95.1-97.0 % with species of the genus Leifsonia, 95.7-96.7 % with species of the genus Herbiconiux, 95.1-96.4 % with species of the genus Salinibacterium and 96.1 % with Labedella gwakjiensis and Homoserinimonas aerilata. The highest sequence similarities (97.0 %) were with Leifsonia aquatica JCM 1368(T), Leifsonia poae VKM Ac-1401(T) and Leifsonia psychrotolerans LI1(T). The peptidoglycan type determined for strain 5GHs34-4(T) was B2γ with dl-2,4-diaminobutyric acid at position 3. The murein was of the acetyl type. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol and two unknown glycolipids. The menaquinones detected were MK-13, MK-12 and MK-14, and the major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), anteiso-C17 : 0 and anteiso-C15 : 0. The phenotypic and phylogenetic traits of strain 5GHs34-4(T) differed in some respects from those of members of the family Microbacteriaceae. Therefore, strain 5GHs34-4(T) is considered to represent a novel species of a new genus in the family Microbacteriaceae, for which the name Rudaibacter terrae gen. nov., sp. nov. is proposed. The type strain is 5GHs34-4(T) ( = KACC 15523(T) = NBRC 108754(T)). PMID:23728372
Bruck, Miguel; Lehner, Susanne
An empirical algorithm (XWAVE) to derive integrated sea state parameters from TerraSAR-X (TS-X) SAR data is developed and validated using NOAA in-situ buoy wave measurements. The comparison for significant wave height and peak wave length was performed as well for deep water locations in open ocean as well as for coastal areas. The significant wave height validation results show a correlation of 0.93% and a scatter index of 0.21 when using in-situ wave buoy data. Verification of the TS-X derived peak wavelength against in-situ buoy data resulted in a correlation of 0.96 and a scatter index of 0.13. The main highlights of TS-X imagery are a higher resolution of up to 1m, when compared to conventional C-band SAR data and a reduction of non-linear imaging effects of a moving target by lower platform altitude. Thus, ocean waves with wavelength less than 30m are detectable. This makes TS-X particularly useful to observe coastal areas where complex bathymetry strongly impacts the approaching waves. In this paper, TS-X images acquired in different coastal areas are presented, including three cases of the German coast and one case near the coast of the Azores Archipelago in the North Atlantic Ocean. Wave fields are derived from the TS-X imagery using the proposed XWAVE algorithm and compared not only to in-situ buoy wave measurements but also to results of a high resolution numerical wave model. The objective was to study the quality of significant wave height field estimation in the spatial domain in highly variable conditions which are typically dominant in coastal areas. The results show that the empirical XWAVE algorithm allows estimating wave fields from TS-X data with high resolution thus showing the spatial information on wave variations. Therefore it is a new useful tool to characterize sea state in coastal areas by remote sensing.
Full Text Available Extraterritorial ownership and control of sub-Saharan African land have a long and troubledhistory. This research investigates a much-studied practicethe recent enclosure of African landand resourcesbut asks a little-studied question: how are non-Africans reasserting terra nulliusnarratives of the past to justify the present transformation of African landscapes? The answersuggested here lies in a bulwark of de facto terra nullius claims couched in security needs of theglobal North and referenced to the low density of Africas rural population, its land and laborunder-utilization, the ambiguity of its land tenure and related low yields, and its arrestedcivilization. De facto terra nullius is neither narrow in scope nor static in application. It isstirring again as a potent justificatory logic for north-south land relations.
Ehlmann, Bethany; Beaty, David; Meyer, Michael
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...
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
Baes, C.F. III; Sharp, R.D.; Sjoreen, A.L.; Hermann, O.W.
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.
Uceda, E.; Fairen, A.; Woodworth-Lynas, C.; Palmero Rodriguez, A.
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
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.
The first report of glucose-6-phosphate dehydrogenase (G6PD) deficiency in Saudi population of the Eastern Province paved the way for extensive investigations to determine the distribution and molecular pathogenesis of G6PD deficiency in Saudis in different parts of the country. During a national study lasting from 1980 to 1993, 24,407 Saudi in 31 different areas of Saudi Arabia screened for G6PD deficiency using spectrophoretic estimation of enzyme activity and electrophoretic separation of the phenotypes. The results in the males and females were separately analyzed and showed a statistically significant difference in the frequency in the male (0.0905) and female (0.041) population (P<0.05). The frequency in the male varied from 0 to 0.398 and in the female from 0 to 0.214. The phenotypes identified included G6PD-A, G6PD-Mediterranean and G6PD-Med-Like with G6PD-B as the normal phenotype in all areas. This study shows that G6PD deficiency is a frequently identified single-gene disorder in Saudi Arabia and G6PD-Mediterranean is the major variant producing the severe deficiency state in this population. (author)
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
Almogbel, Y S; Abughosh, S M; Almogbel, F S; Alhaidar, I A; Sansgiry, S S
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
With the evolution of health services in Saudi Arabia, there has been increase in the number of medical practice litigations. The author analyzed the medical malpractice litigation that was referred to the National Medico-Legal Committee (MLC) in order to evaluate the magnitude and underlying factors of the problem in Saudi Arabia. A retrospective analysis of the official records of Medico-Legal malpractice over the period 1420H-1424H (199-2003) was performed. The incidence among different medical specialties, location, and final resolution of each claim were identified. Data analysis revealed an increasing trend in the total number of claims over the study period, with a sharp increase in the transition between 1422H and 1423H (2001-200). The distribution of claims over different medical specialties showed that obstetrical practice took the lead with 27%, followed by general surgery and subspecialties, represented by 17% each, internal medicine 13%, while pediatrics contributed 10% of claims: the fewest claims were in dentistry with 2.5%. The majority of claims were referred to the Ministry of Health and private sectors medical facilities. Most claims were from the Riyadh region over the period between 1420H to 1422H (1999-2001), while thereafter, during 1423 and 1424H (2002 and 2003), the Holy Capital had the highest number of claims referred to the MLC. Adherence to standards of medical practice is by far the best approach to avoid or reduce the incidence of litigation. (author)
Nadira A Al-Baghli
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.
Fleitmann, Dominik; Burns, Stephen J.; Pekala, Marek; Mangini, Augusto; Al-Subbary, Abdulkarim; Al-Aowah, Mohammad; Kramers, Jan; Matter, Albert
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.
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)
Abdelrahman, M.A.; Nimmo, B.G.
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.
M. A. U Mridha
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.
Bukhari, Najat A; Al-Otaibi, Reem A; Ibhrahim, Mohammed M
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
Rogério Melloni; Eliane Guimarães Pereira Melloni; Lucas Lopes Vieira
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...
Baghdadi, N.; Aubert, M.; Zribi, M.
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...
Haq, Irshad Ul; Graupner, Katharina; Nazir, Rashid; van Elsas, Jan Dirk
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
Mobaraki, A E H; Söderfeldt, B
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
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
Schmitt, Harrison H.
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.
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...... are found to occur predominantly in association with interplanetary sector boundaries, with solar wind dynamic pressure enhancements being the most likely interplanetary driver. In addition it is found that, on time scales of months to several years, the dominant cause of global variability of the magnetic...
Fast, James E.; Dorow, Kevin E.; Morris, Scott J.; Thompson, Robert C.; Willett, Jesse A.
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.
In the mid 21st century, humans finally established a small community on Mars. The Martian colony grew slowly over its first 50 years. There were substantial technical challenges to living in the artificial biospheres. Early colonists had to accept significant restrictions because of the harshness of the environment, and the limited shared physical space. However, by 2116, the community was starting to relax its initial strictures. There was a growing community of young, native Martians. T...
Alston, Christie; Hancock, Sean; Laub, Joshua; Perry, Christopher; Ash, Robert
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.
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.
Wang, Ping; Zheng, Xiaojing
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.
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.
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
Broz, Petr; Hauber, Ernst
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 (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 and possible terrestrial analogs, despite fact that the physical processes behind volcano formation should be similar on both planets. For example, Martian scoria cones are ~2.6 times wider than terrestrial analogues, as lower gravity and atmospheric pressure enable wider dispersion of pyroclasts from the vent. In addition, exit velocities of ejected particles should be increased on Mars because the lower atmospheric pressure favors more rapid exsolution of dissolved gases from the magma, which also favors a wider dispersion of ejected particles. Therefore, care must be taken when applying terrestrial morphometric relationships to the interpretation of hypothesized volcanic features on Mars and other terrestrial bodies. As on Earth, small-scale volcanoes on Mars display diverse shapes and hence provide insight into diverse volcanic processes responsible for such variations. Those diverse processes may point to various mechanisms of magma ascent and eruption styles in dependency on magma properties (e.g., amount of volatiles) and the paleo
McKay, C P
Pictures of Mars from the Viking and Mariner 9 missions provide evidence of liquid water in Mars' past, indicating a warmer climate. It is speculated that outflow channels and valley networks were formed 3.5 to 4 billions years ago, at the same time life was developing on Earth. Current theories suggest that chemical reactions in Mars' early atmosphere depleted the original amounts of carbon dioxide with no mechanism to recycle it back into the atmosphere. Ecosystems in the cold, dry Antarctic valleys provide models of Mars on Earth and indicate that if life evolved on Mars there may be organic or fossil evidence under the surface. Lake beds on Mars surface are considered to be the best place to hunt for fossils. PMID:11540045
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
Digital Terrain Models (DTMs) produced from stereoscopic, submeter-resolution High Resolution Imaging Science Experiment (HiRISE) imagery provide a solid basis for all morphometric analyses of the surface of Mars. In view of the fact that a more effective use of DTMs is hindered by complicated and time-consuming manual handling, the automated process provided by specialists of the Ames Intelligent Robotics Group (NASA), Ames Stereo Pipeline, constitutes a good alternative. Four DTMs, covering the global dichotomy boundary between the southern highlands and northern lowlands along the line of the presumable Arabia shoreline, were produced and analysed. One of them included forms that are likely to be indicative of an oceanic basin that extended across the lowland northern hemisphere of Mars in the geological past. The high resolution DTMs obtained were used in the process of landscape visualisation.
de Vera, J. P.; Lorek, A.; Koncz, A.; Khan, A.; Schulze-Makuch, D.; Möhlmann, D.; Spohn, T.
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.
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.
Murchie, S.; Merenyi, E.; Singer, R.; Kirkland, L.
Spectroscopic studies of altered Martian soils at visible and at NIR wavelengths have generally supported the canonical model of the surface layer as consisting mostly of 2 components, bright red hematite-containing dust and dark gray pyroxene-containing sand. However several of the studies have also provided tantalizing evidence for distinct 1 micrometer Fe absorptions in discrete areas, particularly dark red soils which are hypothesized to consist of duricrust. These distinct absorptions have been proposed to originate from one or more non-hematitic ferric phases. We have tested this hypothesis by merging high spatial resolution visible- and NIR-wavelength data to synthesize composite 0.44-3.14 1lm spectra for regions of western Arabia and Margaritifer Terra. The extended wavelength coverage allows more complete assessment of ferric, ferrous, and H2O absorptions in both wavelength ranges. The composite data show that, compared to nearby bright red soil in Arabia, dark red soil in Oxia has a lower albedo, a more negative continuum slope, and a stronger 3 micrometer H2O absorption . However Fe absorptions are closely similar in position and depth. These results suggest that at least some dark red soils may differ from "normal" dust and mafic sand more in texture than in Fe mineralogy, although there appears to be enrichment in a water-containing phase and/or a dark, spectrally neutral phase. In contrast, there is clear evidence for enrichment of a low-albedo ferric mineral in dark gray soils composing Sinus Meridiani. These have visible- and NIR-wavelength absorptions consistent with crystalline hematite with relatively little pyroxene, plus a very weak 3 micrometer H2O absorption. These properties suggest a Ethology richer in crystalline hematite and less hydrated than both dust and mafic-rich sand.
[figure removed for brevity, see original site] Annotated Version This global map of Mars is based on topographical information collected by the Mars Orbiter Laser Altimeter instrument on NASA's Mars Global Surveyor orbiter. Illumination is from the upper right. The image width is approximately 18,000 kilometers (11,185 miles). Candor Chasma forms part of the large Martian canyon system named Valles Marineris. The location of Southwest Candor Chasma is indicated in the annotated version.
Barabash, Stas; André, Mats; Blomberg, Lars; Lundin, Rickard; Marklund, Göran; Rathsman, Peter; von Schéele, Fredrik; Wahlund, Jan-Erik
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...
Al-Surimi, Khaled; Househ, Mowafa; Almohandis, Essam; Alshagathrh, Fahd
Medical device evaluation presents several unique challenges due to the great diversity and complexity of medical devices and their rapid technological evolution. There has been a variety of work conducted on the development of disease based registries and health surveillance systems in Saudi Arabia. However, the progress of medical device registry systems and post-market medical device surveillance systems remains in its infancy in Saudi Arabia and within the region. In 2007, a royal decree assigned the responsibility for regulating medical devices to the Saudi Food and Drug Authority (SFDA). Soon afterwards, the SFDA established the Medical Devices National Registry (MDNR) to house medical device information relating to manufacturers, agents, suppliers and end-users. The aim of this paper is to provide an overview on the Medical Device National Registry (MDNR) in Saudi Arabia and describe the current experience and future work of establishing a comprehensive medical device registry and post-market surveillance system in Saudi Arabia. PMID:26152943
... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration ICT Trade Mission to Saudi Arabia; Application Deadline Extended AGENCY: International Trade Administration, Department of Commerce. ACTION: Notice. Timeframe for Recruitment...
Al-Mushayt, Omar S; Haq, Kashiful
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...
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.
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.
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…
Cassano, J. J.; Seefeldt, M. W.; Palo, S.; Knuth, S. L.; Bradley, A. C.; Herrman, P. D.; Kernebone, P. A.; Logan, N. J.
In September 2012 five Aerosonde unmanned aircraft were used to make measurements of the atmospheric state over the Terra Nova Bay polynya, Antarctica, to explore the details of air - sea ice - ocean coupling. A total of 14 flights were completed in September 2012. Ten of the flight missions consisted of two unmanned aircraft systems (UAS) sampling the atmosphere over Terra Nova Bay on five different days, with one UAS focusing on the downwind evolution of the air mass and a second UAS flying transects roughly perpendicular to the low level winds. The data from these coordinated UAS flights provide a comprehensive three-dimensional data set of the atmospheric state (air temperature, humidity, pressure, and wind) and surface skin temperature over Terra Nova Bay. The remaining UAS flights during the September 2012 field campaign included two local flights near McMurdo Station for flight testing, a single UAS flight to Terra Nova Bay, and a single UAS flight over the Ross Ice Shelf and Ross Sea polynya. A dataset containing the atmospheric and surface data as well as operational aircraft data has been submitted to the United States Antarctic Program Data Coordination Center (USAP-DCC, http://www.usap-data.org/) for free access (http://gcmd.nasa.gov/getdif.htm?NSF-ANT10-43657, doi:10.15784/600125).
Cassano, John J.; Seefeldt, Mark W.; Palo, Scott; Knuth, Shelley L.; Bradley, Alice C.; Herrman, Paul D.; Kernebone, Peter A.; Logan, Nick J.
In September 2012 five Aerosonde unmanned aircraft were used to make measurements of the atmospheric state over the Terra Nova Bay polynya, Antarctica, to explore the details of air-sea ice-ocean coupling. A total of 14 flights were completed in September 2012. Ten of the flight missions consisted of two unmanned aerial systems (UAS) sampling the atmosphere over Terra Nova Bay on 5 different days, with one UAS focusing on the downwind evolution of the air mass and a second UAS flying transects roughly perpendicular to the low-level winds. The data from these coordinated UAS flights provide a comprehensive three-dimensional data set of the atmospheric state (air temperature, humidity, pressure, and wind) and surface skin temperature over Terra Nova Bay. The remaining UAS flights during the September 2012 field campaign included two local flights near McMurdo Station for flight testing, a single UAS flight to Terra Nova Bay, and a single UAS flight over the Ross Ice Shelf and Ross Sea polynya. A data set containing the atmospheric and surface data as well as operational aircraft data have been submitted to the United States Antarctic Program Data Coordination Center (USAP-DCC, http://www.usap-data.org/) for free access (http://gcmd.nasa.gov/getdif.htm?NSF-ANT10-43657, doi:10.15784/600125).
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.
Akkash, Laith; Badran, Dana; Al-Omari, Aseel Q
Terra Firma forme dermatosis (TFFD) is an infrequently described disorder which features dirt-like lesions that clear after rubbing with alcohol. We describe a series of four patients with the disorder, discuss differential diagnostic considerations and review the literature. PMID:19087214
Biery, Daniel N.; Huff, Zachary T.; Huynh, Amy B.; McFadden, William M.; Mouat, Julia S.; Schneiderman, Scott E.; Song, Hannah; Szpak, Leah E.; Umbaugh, Melanie S.; 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.
Attis and SoilAssassin are two closely related bacteriophages isolated on Gordonia terrae 3612 from separate soil samples in Pittsburgh, PA. The Attis and SoilAssassin genomes are 47,881 bp and 47,880 bp, respectively, and have 74 predicted protein-coding genes, including toxin-antitoxin systems, but no tRNAs. PMID:27365347
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…
Sokolowski, Michel B. C.; Disma, Gerald; Abramson, Charles I.
An operant conditioning situation for the blow fly ("Protophormia terrae novae") is described. Individual flies are trained to enter and reenter a hole as the operant response. Only a few sessions of contingent reinforcement are required to increase response rates. When the response is no longer followed by food, the rate of entering the hole…
Moeller, Chris; Menzel, W. P.; Quinn, Greg
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
Waleed H. BuAli; Abdul Sattar Khan; Mohammad Hussain Al-Qahtani; Shaikha aldossary
Purpose: No study had been conducted to assess the hospitals’ environment for learning purposes in multicenter sites in Saudi Arabia. It aims to evaluate the environment of hospitals for learning purposes of pediatric residents. Methods: We applied Postgraduate Hospital Educational Environment Measure (PHEEM) to measure the learning environment at six teaching hospitals in the Eastern Region of Saudi Arabia from September to December 2013. Results: The number of respondents was 104 (86.7%) ou...
Rayed AlGhamdi; Steve Drew; Thamer Alhussain
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...
The objective of this study is to explore the knowledge, attitudes and intake of energy drinks among adolescents in Saudi Arabia. A multi-stage stratified sampling procedure was carried out to select 1061 school children aged 12–19 years, from Jeddah city, Saudi Arabia. A short self-reported questionnaire was administrated in order to collect the data. Of adolescents in the study, 45% drank energy drinks (71.3% males and 35.9% females; P
Hajar, Saad; Hazmi, Ali Al; Wasli, Mustafa; Mousa, Ahmed; Rabiu, Mansour
Objectives: To determine the prevalence and causes of blindness and diabetic retinopathy (DR) in Jazan district, Southern Saudi Arabia. Methods: Using the standardized Rapid Assessment for Avoidable Blindness (RAAB) and DR cross-sectional methodology, 3800 subjects were randomly selected from the population of ≥50 years of age in Jazan, Saudi Arabia between November 2011 and January 2012. Participants underwent screening comprised of interview, random blood glucose test, and ophthalmic assess...
Hamid, Mohamed E; Mohammed M. Assiry; Joseph, Martin R.; Haimour, Waleed O.; Abdelrahim, Ihab M.; Al-Abed, Fatin; Fadul, Abdalla N.; Ahmed M. Al-Hakami
Objectives: To isolate, identify, and determine the prevalence of Candida and other yeasts of clinical importance in Aseer region, Saudi Arabia. Methods: This is a cross-sectional study involving retrospective analysis of 6100 samples submitted to the Microbiology Laboratory, Aseer Central Hospital, Abha, Saudi Arabia between 2011 and 2012, and prospective isolation and identification of 84 isolates recovered from various clinical specimens presented to the Microbiology Laboratory between 201...
Nouf AlMobarak; Rawan AlAbdulrahman; Shahad AlHarbi; Wea’am AlRashed
This paper reports the results of an online survey study, which was conducted to investigate the use of software project management tools in Saudi Arabia. The survey provides insights of project management in the local context of Saudi Arabia from ten different companies which participated in this study. The aim is to explore and specify the project management tools used by software project management teams and their managers, to understand the supported features that might influence their se...
AL Anazi, Abdullah D.; Alyousif, Mohamed S.
This study aimed to provide recent data on the occurrence of non-strongyle intestinal parasite infestation in horses in the Riyadh region of Saudi Arabia as a basis for developing parasite control strategies. We conducted necropsy for 45 horses from September 2006 to November 2007 in the Riyadh region, Saudi Arabia. 39 out of 45 horses were infected with intestinal parasites with an infestation rate of 86.6%. Infestations with seven nematode species and two species of Gasterophilus larva were...
Mustafa S Saeed; Ali S Alkhoshaiban; Yaser Mohammed Ali Al-Worafi; Chiau Ming Long
The aim of this study is to assess self-medication practice among university students in the Al-Qassim Province of Saudi Arabia. A cross-sectional community-based survey was conducted by distributing a self-administered 18-item questionnaire among university students in the Al-Qassim Province of Saudi Arabia in the period between October and December 2012. The participants were selected using a convenience sampling technique. Data were collected from the questionnaire and analyzed using SPSS ...
Abanmy, Norah O.; Al-quait, Nouf A.; Alami, Amani H.; Al-Juhani, Meshaal H.; Al-Aqeel, Sinaa
In Saudi Arabia, the utilization of the world wide web has become increasingly popular. However, the exact figure of such use is unknown. This study aimed to determine the percentage of, and experience with, online Arabic drug information by Arabic-speaking adults in Saudi Arabia. A web based questionnaire was used. The questionnaire language was Arabic. Public were invited to participate in the survey through e-mails, Twitter, WhatsApp and Facebook in March 2012. The survey included 17 items...
Mutlaq B. Alotaibi
Electronic Commerce (E-Commerce) has a growing potential in Saudi Arabia, due to widespread use of the internet and the maturity of the Information Technology (IT) infrastructure. The purpose of this paper is to assess the quality of E-Commerce websites in Saudi Arabia, using a proposed evaluation instrument. To achieve this aim, six E-Commerce websites were selected for evaluation and then categorized into three categories: domestic, regional and international. Each category consisted of two...
Al-Qurashi, Faisal O.; Abdullah A Yousef; Awary, Bassam H.
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...
OBJECTIVE: To study the clinical presentation, endoscopic features and prevalence of Helicobacter pylori in duodenal ulcer (DU) patients in southern Saudi Arabia, located 3150 m above sea level, and to compare results with those from low altitude regions of the Kingdom.METHODS: Prospective study of patients with proven DU referred for upper gastrointestinal endoscopy at Asir Central Hospital, Abha, southern Saudi Arabia over an 18-month period.RESULTS: Of 126 patients with proven DU, 72% were...
Hasan A Alzahrani,1 Owiss H Alzahrani21Department of Surgery, 2Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi ArabiaObjectives: To identify medical students' perceptions of their learning strategies including, learning habits, resources, and preferred teaching methods, in the Department of Surgery (DOS) of the King Abdulaziz University-Faculty of Medicine (KAU-FoM), in Jeddah, Saudi Arabia.Methods: A cross-sectional descriptive study which was designed to identify stude...
Bassam Hamdar; Hussin Hejase; Tamar Sayed
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...
Mohammed Al-OmranThe Peripheral Vascular Disease Research Chair and Division of Vascular Surgery, Department of Surgery, College of Medicine, King Saud University, Riyadh, Saudi ArabiaPurpose: Atherosclerotic disease (AD) is the leading cause of death worldwide and in Saudi Arabia. Intensive risk reduction therapy plays a major role in reducing adverse cardiovascular outcomes in patients with AD. The level of awareness of this important fact amongst physicians (family physicians, general inte...
Objectives: To investigate the association between stress, shift work, and eating behavior among non-Saudi female nurses working in Central Saudi Arabia. Methods: A sample of 395 non-Saudi female nurses from 2 major hospitals in Riyadh, Kingdom of Saudi Arabia participated in this cross-sectional study. The nurses completed a questionnaire from November 2013 to January 2014 that included items relating to stress and eating behavior using the Dutch Eating Behavior Questionnaire (DEBQ). The que...
Al-Meedani, Laila A.; Al-Dlaigan, Yousef H
Objectives: To determine the prevalence of dental caries, and associated social risk factors among preschool children in Riyadh, Saudi Arabia. Methods: The study consisted of a random sample of 3 to 5 years- old preschool children who were examined in Riyadh, Saudi Arabia; 388 children (184 boys and 204 girls) were examined from 10 different preschools. Each surface of their teeth was examined for dental caries utilizing modified WHO criteria (WHO, 1997). Data information about age, gender an...
Al-maghrabi, T; Dennis, C.
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....
Al-maghrabi, T; Dennis, C.
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...
Al-maghrabi, T; Dennis, C.
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...
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...
Rouzi, Abdulrahim A; Nora Sahly; Dana Sawan; Souzan Kafy; Faten Alzaban
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...
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...
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...
Al-Kadri, Hanan M.; Kamal, Mehak; Bamuhair, Samira S.; Omair, Aamir A.; Bamefleh, Hana S.
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...
Abulkhair, Omalkhair A.; Al Tahan, Fatina M.; Young, Susan E.; Musaad, Salma MA.; Jazieh, Abdul-Rahman M.
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...
El-Gilany, Abdel-Hady; Hammad, Sabry
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...
Al-maghrabi, T; Dennis, C.
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...
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.
Alsultan, S. H.; Rahman, A. A.
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.
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
This paper presents an analysis of energy and exergy utilization in the agricultural sector of Saudi Arabia by considering the sectoral energy and exergy flows for a period of 12 years between 1990 and 2001. Energy and exergy analyses are conducted for its two essential devices, namely tractors and pumps, and hence the sectoral energy and exergy efficiencies are obtained for comparison for a period of 12 years. Two main energy sources are diesel for tractors and electricity for pumps in the sector. It is found that the overall exergy efficiencies in this sector are slightly less than the corresponding energy efficiencies, e.g. 74.19-69.20% for exergy efficiency and 74.94-74.60% for energy efficiency from 1990 to 2001. The present technique is proposed as a useful tool in sectoral analysis of energy and exergy utilization, developing energy policies and providing energy conservation measures
Al-Mofleh, Ibrahim A; Azzam, Nahlah A
We attempted, through systematic review to explore the epidemiology and risk factors of Crohn's disease (CD) with special attention to the Kingdom of Saudi Arabia (KSA). We selected articles that contained population-based, epidemiological, and clinical character studies of CD. We collected data concerned with the prevalence, demographic features, and the possible etiology of CD that might explain its emergence in KSA. The prevalence of CD in Western countries ranged between 11-43/100,000 with flawless evidence of CD prevalence emerging in previously low incidence areas like Asia. Prevalence in KSA has markedly increased over the last 3 decades. Combined ileal and colonic involvement was the most frequently affected site. Diet, smoking, drugs, and westernization of life are assumed to contribute to the pathogenesis. There is convincing evidence of CD emerging in Asia, including KSA. Westernization of lifestyle and smoking is probably the major contributing factors. Genetic studies are warranted. PMID:24252887
Full Text Available This study report results of a survey conducted in the EasternProvince of Saudi Arabia to explore the procedures and financialtechniques that large-size contractors utilise in replacingequipment. The results indicated that contractors set severalreplacement alternatives that they evaluate by using a set ofvarious qualitative and quantitative factors. The contractors’business objectives, employee safety and morale, and, contractors’image in the industry were found to be the most influentialqualitative factors affecting the decision of equipment replacement.Inflation, downtime, obsolescence, salvage value, and depreciationare among the top quantitative factors that contractors considerwhile making a decision to replace equipment. Because of theirsimplicity and practicality, the net present value, payback period,and the economic life are the most popular techniques that areutilised for analysing the financial issues of proposed replacementalternatives.
Alhadlaq, H.; Alshaya, F.; Alabdulkareem, S.; Perkins, K. K.; Adams, W. K.; Wieman, C. E.
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.
Short-wave reflectivity or albedo is an important component of net radiation which represents the major determinant of radiation balance of crop surface. This study was conducted on an irrigated alfalfa crop field at Al-Kharj agricultural area in Saudi Arabia, grown according to normal agricultural practices. Data on radiation balance and crop cover were collected over a number of days from March to October 1986, crop albedo varying from 0–4 in early morning to 0–20 at noon, the overall mean value of the crop albedo being estimated at 0–26. The relation between the individual components of radiation balance was studied, and a significant correlation between incident radiation and net radiation was found. Possible causes responsible for changes in crop albedo were discussed. (author)
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
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.
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,
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.
Oliver M. Lopez
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.
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.
Suaad S. Alwakeel
Full Text Available The occurrence of harmful aflatoxins from agricultural products varies with geographic location, farming practices and processing. To date, no data was reported from Saudi Arabia on mycotoxin content of nuts and edible seeds. Forty samples of edible nuts and dried seeds were randomly collected from different locations in Al-Riyadh, Saudi Arabia. Fungi were detected by seed-plate and dilutions plate method and were cultured on glucose-Czapek's agar, sucrose-Czapek's agar and starch yeast agar. Purified fungal isolates were identified morphologically. Mycotoxins were extractedusing chloroform and detected by thin layer chromatography. Bacterial analysis was done using total plate count method. There was a predominance of A. niger and A. flavus in all medium types. Aflatoxin B1 (8.5 µg mL-1 was detected in peanuts containing A. flavus. Aflatoxin B1 (1.7 µg mL-1 and B2 (1.7 µg mL-1 was detected in sunflower seeds containing A. terreus. T2 toxin (2.8 mg mL-1 was detected in pumpkinseeds containing Stachybotrys chartarum and DAS (2.4 µg mL-1 was detected in a salted peanut sample containing Trichthecium roseum. Four nut samples showed contamination with bacteria. Turkish pine seeds and American walnut had total plate counts of 12x10. Pakistani pine seeds and Iranian salted pistachio had TPC of 3x10. Listeria monocytogenes was isolated from American walnut samples. Government authorities for food safety consumption should continue to monitor and set appropriate guidelines and information initiatives for public knowledge on the safety of these agricultural products whole year round.
Tarek Tawfik Amin
Full Text Available Tarek Tawfik Amin1, Feroze Kaliyadan2, Nouria Saab Al-Muhaidib31Community Medicine Department, Faculty of Medicine, Cairo, Egypt; 2Department of Internal Medicine, Dermatology Section; 3Vice Dean for Female Students, College of Medicine, King Faisal University, Saudi ArabiaObjective: To assess the preferred methods for assessment among medical students at both preclinical and clinical stages of medical education and the possible correlates that promote these preferences.Subjects and methods: All medical students from the third year onwards were surveyed. A self-administered anonymous questionnaire was designed to gather information on the preferred assessment method for course achievement. The preferred methods were also evaluated in relation to cognitive functions. Preference for specific exam format, in the form of multiple choices, short essay questions, or both, and the stated reasons for that preference, was also included in the questionnaire.Results: Out of 310 questionnaires distributed, 238 were returned. Written tests, projects, portfolios, and take home exams were the preferred modes for assessing students’achievements in a course; oral tests including a viva voce were the least preferred type of assessment. Questions that tested the domains of ‘understanding’ and ‘application’ were the most preferred type while those entailing ‘analysis’ were the least preferred. Multiple choice question format was the most preferred type of question (68.7% at both pre- and clinical stages.Conclusion: Students’ assessments at the College of Medicine, King Faisal University, Saudi Arabia, do not use the full range of cognitive domains. The emphasis on higher domains for medical students’ assessment incorporating critical thinking should increase as the students’ progress through their medical courses.Keywords: medical students, assessment, exams, multiple choices, essay
Suliman H Al-Fifi
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.
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
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
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.
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.
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.
Alkhayal A; Aldhukair S; Alselaim N; Aldekhayel S; Alhabdan S; Altaweel W; Magzoub ME; Zamakhshary M
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...
Fry, C. D.; Rosenberg, T. J.; Lutz, L.; Detrick, D. L.; Weatherwax, A. T.; Knouse, E.; Breden, H.; Giganti, J.
The Planetary Surface Instruments Workshop (Meyer et al., LPI Tech. Rpt. 95-05, 1995) identified surface-based radio science instruments as key tools for observing Mars' middle atmosphere, its ionosphere and solar-wind interaction. For example, Mars has a substantial daytime ionosphere, and some important features of the Martian ionosphere can only be observed from below. One instrument, the Relative Ionospheric Opacity Meter (Riometer), is expected to work well on Mars (Detrick et al., PSS, 45, p. 289, 1997). In the past, the size, power requirements and complexity of these instruments have argued against including them on a lander or rover mission, in spite of the potentially rich science return. We describe the development of a miniature radio receiver designed to operate as a Riometer. The development of this receiver was funded by NASA as an enabling technology for future planetary radio science missions. Our receiver includes features that are desirable for extended autonomous operation: low power consumption, wide dynamic range and linearity, computer command and data interface, and the ability to be remotely reconfigured. The receiver design provides significant improvements over previous implementations used in terrestrial riometry. The high degree of system linearity, combined with a digital feedback loop (including a low-duty calibration cycle), allows a longer measurement time. We were able to significantly miniaturize the receiver by using modern, low-power electronic components that have come on the market. We also implemented several of the subsystems in a field-programmable gate array, including the receiver detector, the control logic, and the data acquisition and processing blocks. Considerable efforts were made to eliminate or minimize RF noise and spurious emissions generated by the receiver's digital circuitry. Results of laboratory and field tests are presented and discussed.
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.
Nørnberg, Per; Merrison, Jonathan P.; Gunnlaugsson, Haraldur P.
Laboratory simulations of the Martian surface are of importance to broaden scientific understanding of the physical processes, but also in order to develop the technology necessary for exploration of the planet. The Mars Simulation Laboratory at Aarhus University  has been involved in such simulations for around ten years and has developed several experimental facilities for carrying out science or instrument testing under conditions similar to those at the Martian surface, specifically low pressure, low temperature and importantly recreating the wind flow environment and dust suspension (reproducing the Martian dusty aerosol) using Mars analogue material . The science involved in this simulation work has covered a broad spectrum including, erosion induced mineralogy/chemistry, particulate electrification, magnetic properties of Martian dust, biological survival, UV induced chemistry/mineralogy (using a solar simulator), adhesion/cohesion processes and the wind driven transport of dust and sand [3,4]. With regard to technology the wind tunnel facilities have been used in the development of the latest wind and dust sensing instrumentation [5,6]. With support from the European Space Agency (ESA) and Danish national funding an advanced Mars simulation facility has recently been constructed (2009). This wind tunnel facility has a cross section of 2 x 1 m and a length of 8 m, a temperature range down to below -120C, wind speeds in excess of 20m/s, and automated dust control. With a range of (specialised) sensing instrumentation it provides the opportunity to perform a new generation of scientific experiments and allow testing and technology development in the most realistic and rigorous environment. As well as being available for the space agencies, this facility will be open to all potential scientific collaborators. Also European planetary scientists may benefit from support through the EU Europlanet FP7 networking programme. For more information on access
Juhasz, Antal; Horanyi, Mihaly
We investigate the orbital dynamics of small dust particles generated via the continuous micrometeoroid bombardment of the Martian moons. In addition to Mar's oblateness, we also consider the radiation pressure perturbation that is complicated by the planet's eccentric orbit and tilted rotational axis. Considering the production rates and the lifetimes of dust grains, we show that particles from Deimos with radii of about 15 micrometers are expected to dominate the population of a permanently present and tilted dust torus. This torus has an estimated peak number density of approximately equals 5 x 10(exp -12)/cu cm and an optical depth of approximately equals 4 x 10(exp -8).
Mokhov, N.V.; Striganov, S.I.; /Fermilab
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.
Bulmer, M. H.; Glaze, L.; Barnouin-Jha, O.; Murphy, W.; Neumann, G.
Slope failure and the resulting movement of material downslope on Mars has never been witnessed, making careful data analyses combined with physical modeling the only way to understand their emplacement process. Evidence exists for varying types of landsliding on Mars. They are a significant geomorphic agent in the modification of the surface of Mars and their emplacement style remains contentious. Furthermore, little is known about the slope forming materials and the processes that govern the triggering, failure, and deposition of landslides. We are examining the emplacement of a range of mass movement types in varying geologic settings on Mars by building on detailed landslide field and modeling studies we have conducted on Earth. We have identified a spectrum of different landslide types on Mars ranging from small gully failures such as those in Nirgal Vallis, lobate debris aprons, to large rock avalanches such as those in Ganges Chasma. The deposits associated with gullies and small debris aprons have characteristics analogous to alluvial fans, rock chutes, talus slopes, and debris flows on Earth. The large landslides on Mars have similar attributes to terrestrial rock avalanches and rockslides. Detailed studies on Earth have shown unique topographic and morphological differences between these mass movement types, which have been well documented and that we have examined. We are using Mars Global Surveyor (MGS) data to conduct new geomorphic, topographic and theoretical modeling studies on the emplacement of landslides on Mars at resolutions comparable to those on Earth.
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.
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.
Sulzman, Frank M.; Rummel, John D.; Leveton, Lauren B.; Teeter, Ron
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.
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.
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.
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.
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...
Crisp, Joy A.; Adler, Mark; Matijevic, Jacob R.; Squyres, Steven W.; Arvidson, Raymond E.; Kass, David M.
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.
The miniature biological laboratory of the Viking-1 lander had three experiments to determine, whether the micro-organisms of the Martian soil has: (1) photo-synthetic activity (2) metabolic process activity (utilisation of nutrients) and (3) respiration. The Martian soil was warmed in an incubator and exposed to carbon dioxide (containing C14) in presence of xenon arc lamp to simulate the Sun. If the Martian organisms of the expected type are present in the soil, the gas released during the heating would be radio-active which can be detected by a radiation counter. The three experiments had given positive signals denoting the presence of micro-organisms on the surface of Mars. The presence of superoxide in the soil would be poisonous to life but it is likely that organisms may survive deeper below the soil, where the chemicals would not be formed. The Viking-2 results also offered similar results. However, the basic question whether there is life on Mars still remains unanswered. (K.M.)
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.
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
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...
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...
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...
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...
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...
对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.
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.
Moore, H. J.
Three distinct soillike materials sampled by the Viking landers (VL) on Mars are (in order of increasing strength): (1) drift; (2) crusty to cloddy; and (3) blocky. Relative strengths of these materials are manifested by footpad penetrations during landing (VL 1), depths of deep holes, motor currents during sampling, sampler backhoe penetrations, comminutor motor currents, impact pits, trench tailings, and successful acquisitions of the coarse fraction (only blocky material). Cementation by S Cl compounds probably contributes to the relative strengths. This is shown where the weight pct. of SO3 + Cl of each material is plotted against their relative strengths. A similar result is obtained using SO3 alone, but not with Cl which is deficient in VL 2 samples.
Davies, D. W.
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.
Mctamaney, Louis S.; Douglas, Barry D.; Harmon, Scott Y.
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.
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.
Trigo i Rodriguez, Josep Maria
L’article es centra en la descripció de l’evolució del disc protoplanetari solar que donàlloc a la formació dels planetes. La diferència en composició química dels anomenats planetes interiors -com ara la pròpia Terra- i dels exteriors -com el gegantí Júpiter - és explicada en funció de la temperatura de cada regió en el temps de l’acreció. L’existència de materials lleugers (aigua, matèria orgànica, etc.) en la Terra es justificada corn provenint de matèria interplanetària exterior. Aquests ...
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
Carlos, Ambrósio Joaquim
Atendendo às crescentes preocupações ambientais na indústria da construção e às potencialidades do bambu como material ecológico, neste trabalho, é apresentado uma técnica construtiva sustentável e inovadora de conceção de lajes de terra e bambu. Para tal, foram desenvolvidos ensaios de caracterização mecânica de bambu da espécie Phyllostachys nidulária e de argamassas de terra estabilizadas com cal e/ou cimento. Com os materiais caracterizados, partiu-se para o dimensionamento e construção d...
Full Text Available Spaceborne synthetic aperture radar (SAR measurements of the EarthÃ¢Â€Â™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.
Monica Luri Giboshi; Luiz Henrique Antunes Rodrigues; Francisco Lombardi Neto
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...
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
Seu, Roberto; Phillips, Roger J.; Biccari, Daniela; Orosei, Roberto; Masdea, Arturo; Picardi, Giovanni; Safaeinili, Ali; Campbell, Bruce A.; Plaut, Jeffrey J.; Marinangeli, Lucia; Smrekar, Suzanne E.; Nunes, Daniel C.
SHARAD (SHAllow RADar) is a sounding radar provided by Agenzia Spaziale Italiana (ASI) as a Facility Instrument on the Mars Reconnaissance Orbiter mission. Its 20-MHz center frequency and 10-MHz bandwidth complement the lower-frequency, relatively narrower bandwidth capability of the MARSIS sounding radar. A joint Italian-U.S. team has guided the experiment development and is responsible for data analysis and interpretation. The radar transmits signals at a 700 Hz pulse repetition frequency (PRF) and collects reflections from both the surface and near subsurface of Mars. Vertical and horizontal resolutions are, respectively, 15 m (free-space) and 3-6 km (cross-track) by 0.3-1 km (along-track). The scientific objective of SHARAD is to map, in selected locales, dielectric interfaces to at least several hundred meters depth in the Martian subsurface and to interpret these results in terms of the occurrence and distribution of expected materials, including competent rock, soil, water, and ice. A signal-to-noise ratio of ~50 dB (for a specular surface return) is achieved with 10 W of radiated power by using range and azimuth focusing in ground data processing. Preprocessed data as well as range- and azimuth-focused data will be formatted according to Planetary Data System (PDS) standards and be made available from the ASI Science Data Center (ASDC) and from the Geosciences Node of the Planetary Data System (PDS). Important targets for SHARAD include the polar layered deposits, sedimentary stacks (especially in Terra Meridiani), buried channel systems, buried impact craters, volcanic complexes, and shallow ice deposits in equilibrium with the atmosphere.
Runge, H. [DLR-Institut fuer Methodik Fernerkundung, Oberpfaffenhofen (Germany); Ruhe, M. [DLR-Institut fuer Verkehrsforschung, Berlin-Adlershof (Germany)
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.)
Muehlberger, William; Rice, James W.; Parker, Timothy; Lipps, Jere H.; Hoffman, Paul; Burchfiel, Clark; Brasier, Martin
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.
Allen, M. B.; Neill, I.; Kheirkhah, M.; van Hunen, J.; Davidson, J. P.; Meliksetian, Kh.; Emami, M. H.
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
Thorsten Schuetze; Vicente Santiago-Fandiño
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)...
Ponomarev, Evgenii I.
Variety of radiation power of wildfire was investigated by processing TERRA/Modis imagery in 4 μm spectral band. Fire radiative power (FRP) was used for calibrating high-temperature event database obtained by the satellite technique. An analysis was performed on the database of Siberian wildfires for 2010– 2012. Dynamics of FRP was investigated for a number of wildfires including some cases of crown fire. FRP variation was evaluated for various forest zones of Siberia. Classification...
Sanjuan-Ferrer, Maria J.; Hajnsek, Irena; Papathanassiou, Kostantinos P.
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 ...
Sun, Junqiang; Madhavan, Sriharsha; Xiong, Xiaoxiong; Wang, Menghua
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
Bamler, Richard; Hinz, Stefan; Eineder, Michael
Noch steckt der am 15. Juni 2007 gestartete deutsche Radarfernerkundungssatellit TerraSAR-X mitten in der Erprobungsphase. Doch die Qualität seiner Bilder hat bereits weltweit Aufsehen erregt. Wissenschaftler vom Lehrstuhl für Methodik der Fernerkundung der TUM (Prof. Richard Bamler) und des Deutschen Zentrums für Luft- und Raumfahrt (DLR) entwickelten Auswerteverfahren für diesen Satelliten und führen gemeinsame Forschungsprojekte mit seinen Daten durch.
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.
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...
Clerbaux, Cathy; Edwards, David P.; Deeter, Merritt; Emmons, Louisa; Lamarque, Jean-François; Tie, Xue Xi; Massie, Steve T.; Gille, John
Carbon monoxide (CO) is a key species for tracking pollution plumes. The Measurement Of Pollution in The Troposphere (MOPITT) mission onboard the Terra satellite has already provided 7.5 years of CO atmospheric concentration measurements around the globe. Limited sensitivity to the boundary layer is well known to be a weakness of nadir looking thermal infrared sounders. This paper investigates the possibility of using the MOPITT surface measurements to detect CO emitted by cities and urban ce...
Junqiang Sun; Sriharsha Madhavan; Menghua Wang
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...
Xiong, X.; Salomonson, V. V.; Sun, J.; Chiang, K.; Xiong, S.; Humphries, S.; Barnes, W.; Guenther, B.
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.
Kandirmaz, H. M.; K. Kaba
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...
Glantz, P.; Tesche, M
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 ...
Blonski, Slawomir; Cao, Changyong; Uprety, Sirish; Shao, Xi
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...
Sercel, J. C.; Blandino, J. J.; Wood, K. L.
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...
de Zeeuw van Dalfsen, Elske; Walter, Thomas
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.
Leon, Yoanna; Sciau, Philippe; Goudeau, Philippe; Tamura, Nobumichi; Webb, Sam; Mehta, Apurva
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.
Meister, Gerhard; Eplee, Robert E.; Franz, Bryan A.
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).
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
Marcelo C. Rosa
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.
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.
Almuslmani, B.; Al-Motari, E.; Bingley, R. M.; Teferle, F. N.; Moore, T.
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.
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
... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration U.S. Clean Energy and Energy Efficiency Trade Mission to Saudi Arabia Riyadh and Dhahran, Saudi Arabia April 14-18, 2012 AGENCY: International Trade Administration, Department of Commerce. ACTION: Notice....
Alomair, Miznah O.
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…
Gaafar, A; Fadl, A; el Kadaro, A Y;
is caused by Leishmania major zymodeme LON-1, and in Saudi Arabia by L. major LON-4. Sporotrichoid leishmaniasis was significantly more common in Sudan, occurring in 23% of patients compared with 10% in Saudi Arabia. Lymph node involvement was slightly more prevalent in the Sudan. Clinical and pathological...
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
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.
Hamaker, Joseph; Smith, Keith
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.
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...
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...
Data from the Mars Observer, the first of a new series of unmanned planetary observers, will make Mars one of the best understood of the planets. Of the eight instruments that will be bolted onto the frame of the Mars Observer, four are devoted to elemental and compositional studies of the Red Planet's surface and atmosphere. These include the Gamma Ray Spectrometer, the Visual and Infrared Mapping Spectrometer, the Pressure Modulator Infrared Radiometer, and the Thermal Emission Spectrometer. The other instruments on board - the Mars Observer Camera, a magnetometer, a radar altimeter and radiometer, and radio science equipment - will provide detailed pictures of the surface as well as in-depth data about the planet's magnetic field, surface topography, and atmospheric structure. The data will contain information about how all of these Martian features change during different periods of time
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...
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
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...
Luhmann, J. G.
Although the Phobos-2 spacecraft recently obtained important results relevant to some of the major remaining questions in Mars aeronomy, much remains to be done. In particular, not since the Viking Landers have we made in-situ measurements of aeronomical quantities such as atmospheric and ionospheric densities and temperatures below 400 km altitude. We have never made magnetic field measurements at these altitudes. Without such measurements we cannot unambiguously resolve arguments concerning issues such as the significance of the planetary magnetic field in the solar wind interaction, or understand the atmospheric cycle that leads to escape to space. With the trio of future orbiters including Mars Observer, Mars-94, and Planet-B we should see a veritable explosion of new knowledge, but some gaps in aeronomical science coverage will still remain. This paper briefly reviews some of the major unsolved problems in Mars aeronomy, and points out which are expected to remain outstanding after this flotilla of missions.
Möhlmann, D.; Thomsen, Kaj
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....
Dexter, Carol E.; Kos, Larry
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.
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.
This article sets out to analyse the Saudi gas initiative in the context of the decision-making process in Saudi Arabia between 1998 and 2002. It describes the overall context in which the initiative was made. It focuses on the personalities and institutions that were important in its birth and its evolution. The article argues that a mixture of personalities (especially that of Crown Prince Abdullah and foreign minister Saud al-Faisal) and institutions (especially a clutch of new bodies formed in 1999 and 2000) were pivotal in the emergence of the initiative. It also looks at the obstacles that were placed in the way of the initiative, arguing that Saudi Aramco and the minister of oil, Ali Naimi, were key blocking players. Over time, the Saudi gas initiative has come to be seen as a benchmark of the wider cause of economic liberalization in the Kingdom. The lack of progress in the initiative since the initial indicative contract awards in June 2001 has reflected the lack of movement in the general reformist strategy
B. H. Alharbi
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.
Full Text Available Background/Aim: α-1 antitrypsin (AAT deficiency results from mutations of the protease inhibitor (PI. The AAT gene is mapped on chromosome 14 and has been associated with chronic liver disease and chronic obstructive pulmonary disease (COPD. Objective: To determine the frequency of AAT mutations on S and Z carrier alleles in healthy Saudi individuals from Qassim Province in Saudi Arabia. Patients and Methods : A total of 158 healthy, unrelated participants from Qassim Province were recruited. They were genotyped for the two AAT-deficiency alleles, PIFNx01S and PIFNx01Z, using polymerase chain reaction, with primers designed throughout to mediate site-directed mutagenesis. Results: Of the 158 subjects, 11.39% were carriers for the S mutation (i.e., had the MS genotype, whereas 2.53% were carriers for the Z mutation (i.e., had the MZ genotype. The SZ genotype was present in 3.8% of subjects, while the homozygous genotype SS was present in 1.9% of subjects. No subjects showed the ZZ mutant genotype. Accordingly, frequency of the mutant S and Z alleles of AAT gene was 9.49% and 3.19%, respectively. Conclusion: The results obtained showed a high prevalence of the AAT deficiency allele in the Saudi population. This probably warrants adoption of a screening program for at-risk individuals, so that they might initiate adequate prophylactic measures.
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)
The influences on indoor radon concentrations in Riyadh, Saudi Arabia survey was carried out for 786 dwellings. The measurements were obtained by using a passive integrating ionization system with an E-Perm® Electret ion chamber. Radon levels ranged from 1 to 195 Bq m−3, with a mean value of 24.68 Bq m−3, the geometric mean and the geometric standard deviation are 21 and 2 respectively. 98.5% of the results were below the action level recommended by WHO of 100 Bq.m−3. The results were found to vary substantially due to types of houses and rooms, ventilation, seasons and building materials. Radon concentrations were higher in houses with no ventilation systems, and central air conditioners, and were relatively lower in well ventilated houses with red bricks and water air conditioners. - Highlights: • Limited information about indoor radon in Riyadh. • Several factors influence Radon level were investigated in 786 dwellings in Riyadh over one year. • Some results are over the action level and are advised to improve their ventilation systems
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.
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
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
Background: Acinetobacter baumannii causes infections of respiratory, urinary tract, blood stream and surgical sites. Its clinical significance has increased due to its rapidly developing resistance to major groups of antibiotics used for its treatment. There is limited data available on antimicrobial susceptibility of A. baumannii from Saudi Arabia. Objectives: To determine the patterns of drug resistance of Acinetobacter baumannii and predisposing factors for its acquisition.Subjects and Methods: In this descriptive study, 72 hospitalized patients infected with A baumannii were studied. The clinical and demographic data of the patients were collected using a predesigned questionnaire. Isolation and identification of A.baumannii from all clinical specimens were done using standard microbiological methods. Antibiotic susce ptibility testing was performed by disk diffusion method recommended by Clinical Laboratory Standards Institute. Results: Majority of the isolates (61.1%) were from respiratory tract infections. A.baumannii isolates showed high drug resistance to piperacil lin (93.1%), aztreonam (80.5%), ticarcillin, ampicillin, and tetracycline (76.4%, each) and cefotaxime (75%). Only amikacin showed low rate of resistance compared to other antibiotics (40.3%). About 36% patients had some underlying diseases with diabetes mellitus (11%) being the predominant underlying disease. Conclusions: High antimicrobial resistance to commonly used antibiotics was seen against A.baumannii isolates. Only amikacin was most effective against it. (author)
Abdou, Adel A.
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.
Mubarak Ali AlGahtany
Full Text Available Adeloye-Odeku disease, also known as congenital inclusion dermoid cyst (CIDC of the anterior fontanelle was first described by Adeloye A and Odeku EL, as a solitary congenital subgaleal inclusion dermoid cyst of the anterior fontanelle. This rare lesion was initially thought to be confined to Africans . The universal distribution of this cyst has subsequently been shown in accumulated literature of other ethnic distribution ,Caucasian, Indians, Chinese, Japanese, Turkish and others. This is the first published report that we know of Adeloye-Odeku disease in Arab-Saudi children in Abha, Saudi Arabia. Four patients with Adeloye-Odeku disease, two boys and two girls, Saudi patients with ages ranging from 3months to 9 years are presented. Successful surgical excision of the cyst was achieved in each of the three patients who consented for surgery with no recurrence. The oldest patient did not go for surgery due to parental refusal but the lesion proved to be stable on follow up.
Al-Kheliewi, Abdullah S.; Jamil, M. F.; Basar, M. R.; Tuwaili, W. R.
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.
Ouda, Omar K. M.; Shawesh, Ahmad; Al-Olabi, Tareq; Younes, Firas; Al-Waked, Rafat
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.
Abdalla A Saeed
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.
Sulaiman O. Aljaloud
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.
Abdullah I. Al-Zarah
Full Text Available A field investigation was carried out to determine the Physical and chemical characteristics of Al-Khobar aquifer in the Eastern region of Saudi Arabia. Total Dissolved Solids (TDS varies from 4400 mg L-1 along the Gulf coast on the eastern side to around 1800 mg L-1 on the western side. Sodium (Na is the dominant cation followed by Mg, Ca and K in descending order. Whereas, the anion concentration order is Cl > SO4 > HCO3. Nitrate concentration was found to be higher than the recommended limit for drinking purposes. The Saturation Indices (SI indicated that the regional groundwater is under-saturated with respect to calcite, dolomite, gypsum, anhydrite, halite, pyrite and aragonite minerals and oversaturated with respect to goethite and hematite minerals. The hardness of groundwater is very high as compared to the established standards. The F contents are within permissible limits for drinking. The nitrate contents are within permissible limits for domestic use. Two water types i.e., Na-Ca-Cl-SO4 and Na-Ca-Mg-Cl-SO4 dominate the Al-Ahsa whereas Na-Ca-Cl and Na-Ca-Cl-SO4 water types are dominant in Al-Dammam, Al-Khobar and Al-Qatif areas. Overall, the study provided useful information on some important hydrogeochemical processes in groundwater of the eastern region. Further studies are required to determine heavy trace metals concentration for multiple uses.
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.
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.
Al-Kheliewi, Abdullah S.; Jamil, M. F.; Basar, M. R.; Tuwaili, W. R. [National Center for Radiation Protection, King Abdulaziz City for Science and Technology, 11442 Riyadh (Saudi Arabia)
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.
Passive radon dosimeters, based on alpha particle etched track detectors, were used in the indoor radon survey of the College of Science for Girls in Dammam, Saudi Arabia. A total of 95 dosimeters were distributed in the academic departments and the administrative building in the College. The exposure time in all the buildings was one complete lunar year in the period October 2001-October 2002 to get the average annual indoor radon concentration. All the buildings were constructed with ready-made concrete, except the administrative building which constructed with ordinary concrete bricks. A significant difference in the average indoor radon concentrations in the two types of buildings was found. The average indoor radon concentration in the ready-made concrete buildings was 6+/-2Bqm-3 whereas that for the ordinary concrete brick building was 24+/-2Bqm-3. This could be due to the fact that ready-made concrete has a significantly less voids for the radon to emanate compared with ordinary concrete bricks. The indoor radon concentration in the ground floor is slightly higher than that in the first and second floors
Plesea, Lucian; Hare, Trent
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.
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.
Highlights: • Geochemical evidences on stabile phase confirm Bajocian marl as terra fusca parent material. • Precipitation/Dissolution of secondary carbonates controls geochemistry of labile phases. • This terra fusca sequence record at least four geological and environmental events. - Abstract: Carbonate weathering mantles, like terra fusca, are common in Europe but their formation and evolution is still badly understood. We propose to combine geological, mineralogical and pedological knowledge with trace element and isotope data of a weathering mantle as a novel approach to understand the evolution of terra fuscas. Sr–Nd–Pb isotopes and rare earth element (REE) contents were analyzed in a cambisol developing on a typical terra fusca on top of a condensed Bajocian limestone-marl succession from the eastern side of the Paris Basin. The isotope data, REE distribution patterns and mass balance calculations suggest that the cambisol mirrors the trace element enrichments present in this carbonate lithology, which are exceptionally high compared to global average carbonate. The deeper soil horizons are strongly enriched not only in REE (ΣREE: 2640 ppm) but also in redox-sensitive elements such as Fe (44 wt.%), V (1000 ppm), Cr (700 ppm), Zn (550 ppm), As (260 ppm), Co (45 ppm) and Cd (2.4 ppm). The trace element distribution patterns of the carbonate bedrock are similar to those of the soil suggesting their close genetic relationships. Sr–Nd–Pb isotope data allow to identify four principal components in the soil: a silicate-rich pool close to the surface, a leachable REE enriched pool at the bottom of the soil profile, the limestone on which the weathering profile developed and an anthropogenic, atmosphere-derived component detected in the soil leachates of the uppermost soil horizon. The leachable phases are mainly secondary carbonate-bearing REE phases such as bastnaesite ((X) Ca(CO3)2F) (for X: Ce, La and Nd). The isotope data and trace element
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)
Farmer, J.; Des Marais, D.; Greeley, R.; Landheim, R.; Klein, H.
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.
Al Ahmad, Azzam M; Sallam, Mohamed F; Khuriji, Mohamed A; Kheir, Salah M; Azari-Hamidian, Shahyad
The Kingdom of Saudi Arabia includes fauna from three zoogeographic regions: the Afrotropical, Oriental, and Palaearctic regions. To study the mosquito (Diptera: Culicidae) fauna of these regions in Saudi Arabia, larval collections were made at 15 sites during 2005-2006. Thirty-three species representing nine genera were found. Six species, Anopheles culicifacies Giles s.l., Anopheles subpictus Grassi s.l., Culex arbieeni Salem, Culex simpsoni Theobald, Culex univittatus Theobald, and Ochlerotatus detritus Haliday are reported for the first time for Saudi Arabia. An annotated checklist and an illustrated key to the fourth-instar larvae of the 33 species are presented, along with some remarks about problematic species. Eleven species of genus Anopheles Meigen, five species of tribe Aedini, 13 species of genus Culex L., two species of genus Culiseta Felt, one species of genus Lutzia Theobald, and one species of genus Uranotaenia Lynch Arribátlzaga were recorded during the study. PMID:21845930
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.