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Unique Phenomenon (unique + phenomenon)
Selected AbstractsSeismotectonics of the Sinai subplate , the eastern Mediterranean regionGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2003Amos Salamon SUMMARY We define the Sinai subplate, from a seismotectonic perspective, as a distinct component in the plate tectonics of the eastern Mediterranean region. This is based on the tectonic characteristics of a comprehensive listing of all ML, 4 recorded seismicity in the region during the 20th century, on newly calculated and recalculated fault plane mechanisms of first P -wave arrivals and on published solutions based on waveform inversion of broad-band data. The low seismicity level and scarcity of strong events in the region required a thorough search for useful data and a careful examination of the reliability of the focal solutions. We gathered all available records of first P -wave onsets from the ISS and ISC Bulletins and the local seismic networks. Altogether, we were able to calculate 48 new focal mechanisms and 33 recalculated ones of events that occurred during the years 1940,1992. With the increasing number of teleseismic and regional broad-band stations in the later years, we added 37 solutions based on teleseismic and regional waveform inversions of events that occurred during 1977,2001. These mechanisms enabled us to examine the seismotectonic character of the Sinai subplate. The strike and rake directions of the calculated mechanisms usually reflect the geometry and the large-scale type of deformation observed along the boundaries of the Sinai subplate,the Dead Sea Transform, the Cypriot Arc convergent zone and the Suez Rift. Nevertheless, along each of these boundaries we found anomalous solutions that attest to the complexity of the deformation processes along plate margins. Earthquakes along the Dead Sea Transform exhibit mainly sinistral transtension and transpression, reflecting its leaky manner and local change in the transform geometry. The presence of other unexpected mechanisms near the transform, however, reflects the heterogeneous deformation it induces around. As expected, thrust mechanisms along the Cypriot Arc mirror its convergent nature and typical curved geometry. Transtension and transpressional solutions in the eastern segment of the arc reflect the sinistral shear motion between Anatolia and Sinai there. However, shear mechanisms found between Cyprus and the Eratosthenes Seamount pose a problem regarding its collision process. Most intriguing of all are ML, 4 thrust and shear solutions found in the Gulf of Suez. They are associated with predominantly normal mechanisms within a rift zone and therefore constitute a unique phenomenon, yet to be deciphered. [source] Carnivores and their prey in the Wezmeh Cave (Kermanshah, Iran): a Late Pleistocene refuge in the ZagrosINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 6 2009M. Mashkour Abstract Wezmeh Cave is located on the northeastern edge of the Islamabad plain, a high intermontane valley in the western-central Zagros. In 1999 a disturbed but large faunal assemblage was recovered from this site. The abundant and extremely diverse faunal spectra present at Wezmeh Cave has highlighted the importance of this assemblage. Carnivore remains constitute the bulk of the assemblage; red fox (Vulpes vulpes) has the highest number of identified specimens followed by spotted hyena (Crocuta crocuta), brown bear (Ursus arctos), wolf (Canis lupus), felids (lion, leopard, lynx/caracal and wildcat), mustelids (badger, polecat, marten) and viverrids (mongoose). Artiodactyls (bovid, cervid, suid), equids, rhinoceros (Dicerorhinus sp.) and small animals (Cape hare, porcupine, tortoise, snake, birds) are also present. According to U-series dating, the site was occupied from around 70 ka BP through to sub-recent periods by carnivores. Amongst this rich assemblage, a human fossil tooth was also found and dated by non-invasive spectrometry gamma dating to 20,25 ka BP. A preliminary zooarchaeological and taphonomic study shows that Wezmeh Cave was used by multiple carnivore species, a unique phenomenon in the Zagros Mountains in particular and southwest Asia in general. Copyright © 2008 John Wiley & Sons, Ltd. [source] RNA interference , small RNAs effectively fight viral hepatitisLIVER INTERNATIONAL, Issue 6 2004Amir Shlomai Abstract: RNA interference (RNAi) is the process of sequence-specific gene silencing, initiated by double-stranded RNA that is homologous in sequence to the target gene. This unique phenomenon has been extensively investigated during the last few years not only in the context of its mechanism and its possible role in the regulation of gene expression and cell function, but also as a potential powerful tool for gene therapy. Targeting essential viral genes or oncogenic alleles are only some of the possible applications of RNAi in the field of gene-directed therapy. This review covers the potential use of RNAi against hepatitis B and hepatitis C viruses, the main pathogens causing chronic liver disease. The major milestones along the discovery of RNAi will also be covered. [source] War, Factionalism, and the State in AfghanistanAMERICAN ANTHROPOLOGIST, Issue 3 2002Nazif M. Shahrani Since September 11, 2001, the explanations offered to account for the rise of a foreign-led terrorist network on Afghan soil have variously focused on the political vacuum opened up by the Soviet withdrawal from Afghanistan in February 1989, interference by foreign powers in Afghanistan's internal affairs, the failure of Afghanistan to produce a "strong state" because of ethnic factionalism, and an internal moral incoherence inherent to Afghan culture. I argue that none of these explanations is entirely satisfactory in itself. To understand the situation in Afghanistan, we must recognize that its political and military chaos is not an isolated or unique phenomenon, and at the same time acknowledge the particular social and political dynamics of Afghanistan's history that have set the parameters for current events. I show that communal conflicts in Afghanistan are part of a much wider affliction common to many postcolonial states and multinational societies, and that Afghanistan's current situation can only be understood by focusing on its failed attempts at nation-state building within the broader geopolitical circumstance of foreign manipulation and proxy wars that have given rise to particular forms of ethnic division. [Keywords: Afghanistan, nation-building, ethnic factionalism, warfare, the State] [source] New Dihydroxy Bis(Oxazoline) Ligands for the Palladium-Catalyzed Asymmetric Allylic Alkylation: Experimental Investigations of the Origin of the Reversal of the EnantioselectivityCHEMISTRY - A EUROPEAN JOURNAL, Issue 3 2004Hassan Aït-Haddou Dr. Abstract The origin of the reversal of the enantioselectivity in the palladium-catalyzed allylic alkylation of rac -1,3-diphenyl-2-propenyl acetate with dimethyl malonate anion using chiral dihydroxy bis(oxazoline) "BO" ligands derived from (1S,2S)-(+)-2-amino-1-phenyl-1,3-propanediol was investigated. To determine the structural effects of the dihydroxy BO ligand on this unique phenomenon, new homochiral dihydroxy BO ligands were prepared from L -threonine and L -serine and were assessed in the transformation. The results obtained with these novel BO ligands, compared with the one obtained by using the dihydroxy BO ligands derived from (1S,2S)-(+)-2-amino-1-phenyl-1,3-propanediol, reveal that the reversal in the enantioselectivity observed with the dihydroxy BO ligand depends on the structure of the ligand. The effect of different bases used to generate the dimethyl malonate anion was also examined. The results are discussed in terms of the interaction of one hydroxy group in the intermediate ,-allyl palladium complex with the dimethyl malonate anion. [source] | ||||||||||