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Asmara, Eritrea

The University of Asmara was a public university in Asmara, Eritrea. The nation's first university, it was founded in 1958 by the Piae Madres Nigritiae . The school was meant to provide for the local population, though its initial enrollment in the 50s was entirely Italian. Wikipedia.

ArRajehi A.,King Abdulaziz City for Science and Technology | McClusky S.,Massachusetts Institute of Technology | Reilinger R.,Massachusetts Institute of Technology | Daoud M.,Syrian National Earthquake Center | And 13 more authors.
Tectonics | Year: 2010

Five years of continuously recording GPS observations in the Kingdom of Saudi Arabia together with new continuous and survey-mode GPS observations broadly distributed across the Arabian Peninsula provide the basis for substantially improved estimates of present-day motion and internal deformation of the Arabian plate. We derive the following relative, geodetic Euler vectors (latitude (̊N), longitude (̊E), rate (̊/Myr, counterclockwise)) for Arabia-Nubia (31.7 ± 0.2, 24.6 ± 0.3, 0.37 ± 0.01), Arabia-Somalia (22.0 ± 0.5, 26.2 ± 0.5, 0.40 ± 0.01), Arabia-India (18.0 ± 3.8, 87.6 ± 3.3, 0.07 ± 0.01), Arabia-Sinai (35.7 ± 0.8, 17.1 ± 5.0, 0.15 ± 0.04), and Arabia-Eurasia (27.5 ± 0.1, 17.6 ± 0.3, 0.404 ± 0.004). We use these Euler vectors to estimate present-day stability of the Arabian plate, the rate and direction of extension across the Red Sea and Gulf of Aden, and slip rates along the southern Dead Sea fault south of the Lebanon restraining bend (4.5-4.7 ± 0.2 mm/yr, left lateral; 0.8-1.1 ± 0.3 mm/yr extension) and the Owens fracture zone (3.2-2.5 ± 0.5 mm/yr, right lateral, increasing from north to south; 1-2 mm/yr extension). On a broad scale, the Arabian plate has no resolvable internal deformation (weighted root mean square of residual motions for Arabia equals 0.6 mm/yr), although there is marginally significant evidence for N-S shortening in the Palmyride Mountains, Syria at ≤1.5 mm/yr.We show that present day Arabia plate motion with respect to Eurasia is consistent within uncertainties (i.e., ±10%) with plate tectonic estimates since the early Miocene when Arabia separated from Nubia. We estimate the time of Red Sea and Gulf of Aden rifting from present-day Arabia motion, plate tectonic evidence for a 70% increase in Arabia-Nubia relative motion at 13 Ma, and the width of the Red Sea and Gulf of Aden and find that rifting initiated roughly simultaneously (±2.2 Myr) along the strike of the Red Sea from the Gulf of Suez to the Afar Triple Junction, as well as along the West Gulf of Aden at 24 ± 2.2 Ma. Based on the present kinematics, we hypothesize that the negative buoyancy of the subducted ocean lithosphere beneath the Makran and the Zagros fold-thrust belt is the principle driver of Arabia-Eurasia convergence and that resisting forces associated with Arabia-Eurasia continental collision have had little impact on plate motion. © 2010 by the American Geophysical Union. Source

Tesfamichael D.,University of British Columbia | Tesfamichael D.,University of Asmara | Pitcher T.J.,University of British Columbia | Pauly D.,University of British Columbia
Ecology and Society | Year: 2014

The data requirements for most quantitative fishery assessment models are extensive, and most of the fisheries in the world lack time series of the required biological and socioeconomic data. Many innovative approaches have been developed to improve data collection for fisheries. We explored the use of data from fishers' interviews to estimate time series of approximate "best" catch rates. A total of 472 standardized interviews were conducted with 423 fishers along the southern Red Sea coast recording the best catch recalled and the change in average catch rates throughout the fishing career of interviewees. The results showed a decline of best catch rates in all fisheries, ranging from 4% to 10% per year for more than 50 years. The estimated rates of decline of the typical catch were higher for fishers who started fishing in recent years, suggesting that the resource base is declining, in concordance with other indicators. It is suggested that analysis of approximate data, quickly acquired at low cost from fishers through interviews, can be used to supplement other data-recording systems or used independently to document the changes that have occurred in the resource base over a lifetime of fishing. The results can be used to guide the assessment and management of resources to conserve ecosystems and livelihoods. © 2014 by the author(s). Source

Teklay M.,University of Asmara | Teklay M.,University of Munster | Scherer E.E.,University of Munster | Mezger K.,University of Munster | Danyushevsky L.,University of Tasmania
Contributions to Mineralogy and Petrology | Year: 2010

The Afar Depression offers a rare opportunity to study the geodynamic evolution of a rift system from continental rifting to sea floor spreading. This study presents geochemical data for crustal and mantle xenoliths and their alkaline host basalts from the region. The basalts have enriched REE patterns, OIB-like trace element characteristics, and a limited range in isotopic composition (87Sr/86Sr = 0.70336-0.70356, εNd = +6.6 to +7.0, and εHf = +10.0 to +10.7). In terms of trace elements and Sr-Nd isotopes, they are similar to basalts from the Hanish and Zubair islands in the southern Red Sea and are thus interpreted to be melts from the Afar mantle. The gabbroic crustal xenoliths vary widely in isotope composition (87Sr/86Sr = 0.70437-0.70791, εNd = -8.1 to +2.5, and εHf = -10.5 to +4.9), and their trace element characteristics match those of Neoproterozoic rocks from the Arabian-Nubian Shield and modern arc rocks, suggesting that the lower crust beneath the Afar Depression contains Neoproterozoic mafic igneous rocks. Ultramafic mantle xenoliths from Assab contain primary assemblages of fresh ol + opx + cpx + sp ± pl, with no alteration or hydrous minerals. They equilibrated at 870-1,040°C and follow a steep geothermal gradient consistent with the tectonic environment of the Afar Depression. The systematic variations in major and trace elements among the Assab mantle xenoliths together with their isotopic compositions suggest that these rocks are not mantle residues but rather series of layered cumulate sills that crystallized from a relatively enriched picritic melt related to the Afar plume that was emplaced before the eruption of the host basalts. © 2009 The Author(s). Source

Tsegai A.T.,Northeast Normal University | Tsegai A.T.,University of Asmara | Wang L.,Northeast Normal University | Wang D.,Northeast Normal University | And 4 more authors.
Basic and Applied Ecology | Year: 2013

Several studies have shown that consumption of a focal plant by herbivores depends not only on its own defense traits but also on the characteristics of the neighboring plants. A number of studies have reported on plant associational defense in relation to neighboring plant palatability but the effect of the spatial distribution of the focal plant within patches of different neighboring plants has received less attention. We conducted a manipulative experiment to determine whether and how spatial distribution of focal plants affects the associational defense between plant species. In our experimental setup sheep encountered two patches varying in spatial distribution of the focal plant within patches (dispersed or clumped) and patch quality, good patch and bad patch, where the focal plant, Lathyrus quinquenervius, was neighbored to high- (Chloris virgata) or low-palatable (Kalimeris integrifolia) species, respectively. Results showed that, when focal plants were dispersed within both patches, the risk of attack was significantly lower for focal plants in the patches with low- than high-palatable neighbors, indicating associational defense. Alternatively, when focal plants were clumped within both patches, they were consumed in bad-patch as much as in good-patch plots, which indicates the absence of associational defense. However, if the focal plants have different spatial distributions in the two patches (dispersed in good-patch and clumped in bad-patch or vice versa), sheep foraging success for focal plants was greatly reduced in dispersed spatial pattern irrespective of the palatability of neighboring plants. Therefore, we concluded that spatial distribution is as important as traits of neighboring plants in predicting vulnerability of the focal plant to grazing by generalist herbivores. The outcome of plant associational defense for different types of neighborhood strongly depends on the magnitude of herbivore foraging selectivity between and within patches, which further depended on the contrasts between plant species or between patches. © 2013 Gesellschaft für Ökologie. Source

Ghinassi M.,University of Padua | Billi P.,University of Ferrara | Libsekal Y.,University of Asmara | Papini M.,University of Florence | Rook L.,University of Florence
Journal of Sedimentary Research | Year: 2013

Sedimentological and architectural data from three-dimensional larger vertical outcrops of Pleistocene fluvial deposits of the Dandiero Basin (Eritrean Danakil depression) are here used to reconstruct planform evolution of a meander bend and investigate the role of overbank flooding in sediment distribution on point bars. The point bar accumulated as part of a lowstand systems tract at the base of an incised valley cut into lacustrine mud. Selected outcrops transect a 1-km-long channel belt exposed parallel to the main fluvial transport direction. Sedimentological logs, outcrop line drawings, and paleocurrent and bedding measurements show that this outcrop belt represents a transverse section of an asymmetric fluvial point bar, which accumulated through migration of a channel 6 m deep and 70 m wide. This bar was characterized by early expansion followed by downstream accretion, which was abruptly interrupted by lacustrine deposition. The onset of downstream accretion started when the channel expanded to reach the more resistant valley wall. Sediment accreted on the downstream side of the point bar and accumulated both during bankfull discharge and overbank floods, with significant modification of the channel flow where the floodwater re-entered the main channel (i.e., riffle zone). In this zone, a secondary circulation cell triggered a shift of erosion toward the inner bank and scrolling on the downstream side of the point bar. Copyright © 2013, SEPM (Society for Sedimentary Geology). Source

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