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