835 resultados para Eastern Screech Owls


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The Jebel Ressas Pb-Zn deposits in North-Eastern Tunisia occur mainly as open-space fillings (lodes, tectonic breccia cements) in bioclastic limestones of the Upper Jurassic Ressas Formation and along the contact of this formation with Triassic rocks. The galena-sphalerite association and their alteration products (cerussite, hemimorphite, hydrozincite) are set within a calcite gangue. The Triassic rocks exhibit enrichments in trace metals, namely Pb, Co and Cd enrichment in clays and Pb, Zn, Cd, Co and Cr enrichment in carbonates, suggesting that the Triassic rocks have interacted with the ore-bearing fluids associated with the Jebel Ressas Pb-Zn deposits. The delta(18)O content of calcite associated with the Pb-Zn mineralization suggests that it is likely to have precipitated from a fluid that was in equilibrium with the Triassic dolostones. The delta(34)S values in galenas from the Pb-Zn deposits range from -1.5 to +11.4%, with an average of 5.9% and standard deviation of 3.9%. These data imply mixing of thermochemically-reduced heavy sulfur carried in geothermal- and fault-stress-driven deep-seated source fluid with bacterially-reduced light sulfur carried in topography-driven meteoric fluid. Lead isotope ratios in galenas from the Pb-Zn deposits are homogenous and indicate a single upper crustal source of base-metals for these deposits. Synthesis of the geochemical data with geological data suggests that the base-metal mineralization at Jebel Ressas was formed during the Serravallian-Tortonian (or Middle-Late Miocene) Alpine compressional tectonics.

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Standard practice of wave-height hazard analysis often pays little attention to the uncertainty of assessed return periods and occurrence probabilities. This fact favors the opinion that, when large events happen, the hazard assessment should change accordingly. However, uncertainty of the hazard estimates is normally able to hide the effect of those large events. This is illustrated using data from the Mediterranean coast of Spain, where the last years have been extremely disastrous. Thus, it is possible to compare the hazard assessment based on data previous to those years with the analysis including them. With our approach, no significant change is detected when the statistical uncertainty is taken into account. The hazard analysis is carried out with a standard model. Time-occurrence of events is assumed Poisson distributed. The wave-height of each event is modelled as a random variable which upper tail follows a Generalized Pareto Distribution (GPD). Moreover, wave-heights are assumed independent from event to event and also independent of their occurrence in time. A threshold for excesses is assessed empirically. The other three parameters (Poisson rate, shape and scale parameters of GPD) are jointly estimated using Bayes' theorem. Prior distribution accounts for physical features of ocean waves in the Mediterranean sea and experience with these phenomena. Posterior distribution of the parameters allows to obtain posterior distributions of other derived parameters like occurrence probabilities and return periods. Predictives are also available. Computations are carried out using the program BGPE v2.0

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From 6 to 8 November 1982 one of the most catastrophic flash-flood events was recorded in the Eastern Pyrenees affecting Andorra and also France and Spain with rainfall accumulations exceeding 400 mm in 24 h, 44 fatalities and widespread damage. This paper aims to exhaustively document this heavy precipitation event and examines mesoscale simulations performed by the French Meso-NH non-hydrostatic atmospheric model. Large-scale simulations show the slow-evolving synoptic environment favourable for the development of a deep Atlantic cyclone which induced a strong southerly flow over the Eastern Pyrenees. From the evolution of the synoptic pattern four distinct phases have been identified during the event. The mesoscale analysis presents the second and the third phase as the most intense in terms of rainfall accumulations and highlights the interaction of the moist and conditionally unstable flows with the mountains. The presence of a SW low level jet (30 m s-1) around 1500 m also had a crucial role on focusing the precipitation over the exposed south slopes of the Eastern Pyrenees. Backward trajectories based on Eulerian on-line passive tracers indicate that the orographic uplift was the main forcing mechanism which triggered and maintained the precipitating systems more than 30 h over the Pyrenees. The moisture of the feeding flow mainly came from the Atlantic Ocean (7-9 g kg-1) and the role of the Mediterranean as a local moisture source was very limited (2-3 g kg-1) due to the high initial water vapour content of the parcels and the rapid passage over the basin along the Spanish Mediterranean coast (less than 12 h).

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The aim of the study was to assess the clinical performance of the model combining areal bone mineral density (aBMD) at spine and microarchitecural texture (TBS) for the detection of the osteoporotic fracture. The Eastern European Study is a multicenter study (Serbia, Bulgaria, Romania and Ukraine) evaluating the role of TBS in routine clinical practice as a complement to aBMD. All scans were acquired on Hologic Discovery and GE Prodigy densitometers in a routine clinical manner. The additional clinical values of aBMD and TBS were analyzed using a two steps classification tree approach (aBMD followed by TBS tertiles) for all type of osteoporotic fracture (All-OP Fx). Sensitivity, specificity and accuracy of fracture detection as well as the Net Reclassification Index (NRI) were calculated. This study involves 1031 women subjects aged 45 and older recruited in east European countries. Clinical centers were cross-calibrated in terms of BMD and TBS. As expected, areal BMD (aBMD) at spine and TBS were only moderately correlated (r (2) = 0.19). Prevalence rate for All-OP Fx was 26 %. Subjects with fracture have significant lower TBS and aBMD than subjects without fracture (p < 0.01). TBS remains associated with the fracture even after adjustment for age and aBMD with an OR of 1.27 [1.07-1.51]. When using aBMD T-score of -2.5 and the lowest TBS tertile thresholds, both BMD and TBS were similar in terms of sensitivity (35 vs. 39 %), specificity (78 vs. 80 %) and accuracy (64 vs. 66 %). aBMD and TBS combination, induced a significant improvement in sensitivity (+28 %) and accuracy (+17 %) compared to aBMD alone whereas a moderate improvement was observed in terms of specificity (+9 %). The overall combination gain was 36 % as expressed using the NRI. aBMD and TBS combination decrease significantly the number of subjects needed to diagnose from 7 for aBMD alone to 2. In a multi-centre Eastern European cohort, we have shown that the use of TBS in addition to the aBMD permit to reclassified correctly more than one-third of the overall subjects. Furthermore, the number of subjects needed to diagnose fell to 2 subjects. Economical studies have to be performed to evaluate the gain induced by the use of TBS for the healthcare system.

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The results of a coupled, in situ laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb study on zircon and geochemical characterization of the Eastern Cordilleran intrusives of Peru reveal 1.15 Ga of intermittent magmatism along central Western Amazonia, the Earth's oldest active open continental margin. The eastern Peruvian batholiths are volumetrically dominated by plutonism related to the assembly and breakup of Pangea during the Paleozoic-Mesozoic transition. A Carboniferous-Permian (340-285 Ma) continental arc is identified along the regional orogenic strike from the Ecuadorian border (6 degrees S) to the inferred inboard extension of the Arequipa-Antofalla terrane in southern Peru (14 degrees S). Widespread crustal extension and thinning, which affected western Gondwana throughout the Permian and Triassic resulted in the intrusion of the late- to post-tectonic La Merced-San Ramon-type anatectites dated between 275 and 220 Ma, while the emplacement of the southern Cordillera de Carabaya peraluminous granitoids in the Late Triassic to Early Jurassic (220-190 Ma) represents, temporally and regionally, a separate tectonomagmatic event likely related to resuturing of the Arequipa-Antofalla block. Volcano-plutonic complexes and stocks associated with the onset of the present Andean cycle define a compositionally bimodal alkaline suite and cluster between 180 and 170 Ma. A volumetrically minor intrusive pulse of Oligocene age (ca. 30 Ma) is detected near the southwestern Cordilleran border with the Altiplano. Both post-Gondwanide (30-170 Ma), and Precambrian plutonism (691-1123 Ma) are restricted to isolated occurrences spatially comprising less than 15% of the Eastern Cordillera intrusives. Only one remnant of a Late Ordovician intrusive belt is recognized in the Cuzco batholith (446.5 +/- 9.7 Ma) indicating that the Famatinian arc system previously identified in Peru along the north-central Eastern Cordillera and the coastal Arequipa-Antofalla terrane also existed inboard of this parautochthonous crustal fragment. Hitherto unknown occurrences of late Mesoproterozoic and middle Neoproterozoic granitoids from the south-central cordilleran segment define magmatic events at 691 +/- 13 Ma, 751 +/- 8 Ma, 985 +/- 14 Ma, and 1071-1123 +/- 23 Ma that are broadly coeval with the Braziliano and Grenville-Sunsas orogenies, respectively. Our data suggest the existence of a continuous orogenic belt in excess of 3500 km along Western Amazonia during the formation of Rodinia, its ``early'' fragmentation prior to 690 Ma, and support a model of reaccretion of the Paracas-Arequipa-Antofalla terrane to western Gondwana in the Early Ordovician with subsequent detachment of the Paracas segment in form of the Mexican Oaxaquia microcontinent in Middle Ordovician. A tectonomagmatic model involving slab detachment, followed by underplating of cratonic margin by asthenospheric mantle is proposed for the genesis of the volumetrically dominant Late Paleozoic to early Mesozoic Peruvian Cordilleran batholiths.

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Climate change acts as a major new selective agent on many organisms, particularly at high latitudes where climate change is more pronounced than at lower latitudes. Studies are required to predict which species are at a high risk of extinction and whether certain phenotypes may be more affected by climate change than others. The identification of susceptible phenotypes is important for evaluating the potential negative effect of climate change on biodiversity at the inter- and intraspecific levels. Melanin-based coloration is an interesting and easily accessible candidate trait because, within certain species, reddish pheomelanin-based coloration is associated with adaptations to warm climates. However, it is unclear whether the same holds among species. We tested one prediction of this hypothesis in four owl genera (wood, scops, screech, and pygmy owls), namely that darker reddish species are more prevalent near the equator than polewards. Our comparative analysis is consistent with this prediction for the northern hemisphere, suggesting that pale reddish species may be adapted to cold climates and dark reddish species to warmer climates. Thus, climate change may have a larger negative impact on pale pheomelanic owls and favour dark pheomelanic species.

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When exposed to parasites, hosts often mount energetically expensive immune responses, and this may alter resource allocation between competing life history traits including other components of the immune system. Here, we investigated whether a humoral immune challenge towards a vaccine reduces or enhances the cutaneous immune responses towards an injection of lipopolysaccharid (LPS, innate immunity) and phytohaemagglutinin (PHA, T-cell immunity) in nestling tawny owls in interaction with the degree of plumage melanin-based coloration. The humoral immune challenge enhanced the response to LPS similarly in differently coloured nestlings. In contrast, the same humoral immune challenge enhanced immune response to PHA in dark reddish melanic nestlings while reducing it in pale reddish melanic nestlings. Our results highlight that both antagonistic and synergistic interactions can take place among branches of immune system, and that the sign and magnitude of these interactions can vary with immune responses involved and the degree of melanin-based coloration.

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This paper is concerned with the organization of societies in north-eastern Iberia (present-day Catalonia) during the Iron Age, using data provided by domestic architecture and settlement organization. I offer an analysis of the social differences detected in the dwellings based on a sample of houses excavated at different types of settlement. Although many Iberian houses had simple layouts and small surface areas, some larger dwellings at the main sites are distinguished by the shape of their ground plans, their surface areas, architectural features, and central locations; these houses are believed to be the residences of the Iberian elite. Such dwellings are not found at all sites and the data suggest that there was a relationship between the category of the settlement (or its function) and the types of dwelling in it.

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BACKGROUND: Hodgkin lymphoma (HL) is a largely curable disease and its mortality had steadily declined in western Europe since the late 1960s. Only modest declines were, however, observed in central/eastern Europe. MATERIALS AND METHODS: We updated trends in mortality from HL in various European areas up to 2004 and analyzed patterns in incidence for selected European countries providing national data. RESULTS: In most western European countries, HL mortality continued to steadily decline up to the mid 2000s. More recent reductions were also observed in eastern European countries. Overall, mortality from HL declined from 1.17/100,000 (age-standardized, world population) in 1980-1989 to 1.42/100,000 in 2000-2004 in men from the 15 member states of the European Union (EU) from western and northern Europe. In the EU 10 accession countries of central and eastern Europe, male mortality from HL was 1.42/100,000 in 1980-1984, 1.32 in 1990-1994, and declined to 0.76 in 2000-2004. Similar trends were observed in women. No consistent patterns were found for HL incidence. CONCLUSIONS: The present work confirms the persistent declines in HL mortality in western European countries, and shows favorable patterns over more recent calendar years in central/eastern ones, where rates, however, are still at levels observed in western Europe in the early 1990s.

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The karyotype, morphology and biology of Crocidura from Fuerteventura (Canary Islands) are described. The species has a diploid chromosome number of 2n = 36, thus differing from all other species of the genus. A detailed morphological comparison of the shrews from Fuerteventura, Lanzarote and other islets with C. russula from Morocco revealed specific characters for both taxa. Differences were also observed in biological parameters. It is concluded that the Canary Island populations of Crocidura form a biological species which is consequently named Crocidura canariensis sp. nov.

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This publication deals with various aspects of European Union enlargement effects faced by the companies from EU15 and especially from Finland when doing business in the ten transitional economies which joined European Union in 2004 and 2007