984 resultados para Great Western Railway
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The overarching goal of the proposed research was to evaluate the hydraulic performance of twenty two (22) fish-passage structures located in close proximity to bridges in western Iowa and within the HCA (Hungry Canyon Alliance) territory. Such structures include riprap weirs, fish ladders and grouted ripraps. The hydraulic performance of the aforementioned structures was evaluated via detailed field tests for a range of flow conditions relevant to fish migration through bridge waterways in different streams in western Iowa.
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Résumé Le « terrane » d'Anarak-Jandak occupe une position géologique clé au nord-ouest du Microcontinent Centre-East Iranien (CE1M), connecté avec le Bloc du Grand Kavir et la ceinture métamorphique de Sanandaj-Sirjan. Nous discutons ici l'origine de ces différentes unités, reliées jusqu'à présent à des épisodes orogéniques d'âge Précambrien à Paléozoïque inférieur, pour conclure finalement de leur affinité paléotéthysienne. Leur histoire commence par un épisode de rifting d'âge Ordovicien supérieur-Dévonien inférieur, pour se terminer au Trias par la collision des blocs Cimmériens dérivé du Gondwana avec le Bloc du Turan d'affinité asiatique (événement Eocimmérien). La plus importante unité métamorphique affleurant au sud-ouest de la région de Jandak-Anarak-Kaboudan est une épaisse séquence silicoclastique à grains fins contenant des blocs ophiolitiques (marginal-sea-type), et des associations basalte-gabbro à signatures géochimiques de type supra-subduction. Dans la région de Nakhlak, nous avons daté ces gabbros par la méthode U-Pb à 387f0.11 Ma ; les roches métamorphiques pélitiques ont donné des âges de refroidissement Ar-Ar pour la muscovite de 320 à 333 Ma. Ce complexe d'accrétion "varisque" a été métamorphisé dans le faciès schiste vert-amphibolite au cours de l'accrétion de la ceinture granitique d'Airekan, d'âge Cambrien inférieur (549±15 Ma par la méthode U/Pb), qui affleure aujourd'hui à l'extrémité nord-ouest du terrane d'Anarak-Jandak . La subduction vers le nord de l'océan Paléotéthys depuis le Paléazoïque supérieur jusqu'au Trias, a permis l'accumulation de grandes quantités de matériel océanique dans la zone de subduction. Par exemple, une succession de guyots (Anarak, Kaboudan, et Meraji Seamounts) et de hauts sous-marins, entrés en collision oblique avec le prisme d'accrétion, est à l'origine d'un léger métamorphisme de type HP qui affecte ces séries {âges Ar-Ar de 280 à 230 Ma). De plus, le magmatisme bimodal de Chah Gorbeh est caractérisé d'une part par des roches de type trondjémite-gabbros (262 Ma), d'autre part par des laves en coussin de type basaltes alcalins-rhyolites; ces roches magmatiques ont recoupé l'ophiolite d'Anarak lors de la mise en place de cette dernière dans la fosse interne de subduction. Quant au prisme d'accrétion de Doshakh, d'âge essentiellement Permien supérieur, i1 a été accrété le long de la marge continentale et métamorphisé dans le faciès schiste vert. La fermeture de la Paléotéthys s'enregistre finalement par la sédimentation dans le bassin d'avant pays du flysch de Bayazeh, d'âge probable Triasique. Le matériel issu de l'arc magmatique de la Paléotéthys est très bien préservé dans les dépôts infra-arc Dévonien supérieur-Carbonifère de Godar-e-Siah, ainsi que dans la succession d'avant-arc de Nakhlak. Pendant l'intervalle Paléozoïque supérieur-Trias, la région de Jandak a été soumise à un régime extensif de type bassin d'arrière-arc, dont un témoin pourrait être la ceinture ophiolitique d'Arusan, elle-même comparable aux écailles ophiolitiques d'Aghdarband au nord-est de l'Iran. Cet ensemble métamorphique est recoupé par des granites d'arc à collisionnel datés à 215±15 Ma. Dans la région de Yazd, témoin de la marge passive Cimmérienne, la sédimentation syn-rift Silurienne à Dévonienne inférieure a été interrompue pendant l'intervalle Trias moyen-Trias supérieur; il en a été de même pour les dépôts de plate-forme Paléozoïque supérieur. L'érosion, qui dans ce dernier cas a atteint le Permien, pourrait être liée au bombement flexural de la marge passive. La collision finale n'a pas induit de déformations trop importantes, et se caractérise par la mise en place de nappes sur la marge passive. Cet événement est scellé par des dépôts molassique du Lias. D'un point de vue régional, la zone s'étendant actuellement de la Mer Noire au Pamir a été soumise à six épisodes d'extension-compression du Jurassique inférieur (début du l'ouverture en position arrière-arc de la Néotéthys) à l'Eocène moyen. Par exemple, le terrane d'AnarakJandak, probablement situé entre le Kopeh Dagh et la plate-forme nord Afghane, s'est complètement détaché de sa patrie d'origine au début du Crétacé supérieur. Des preuves de cet événement se retrouvent dans les séries de plate-forme de Khur (préservation de séries syn-rift puis de marge passive). Les ophiolites de Nain et de Sabzevar sont de plus interprétée comme un témoin de l'existence de ce bassin d'arrière-arc. Dans l'intervalle Eocène-Oligocène, l'indentation par la plaque indienne de l'Eurasie a été contemporaine de la rotation horaire de fragments de l'ancien microcontinent Iranien et de la formation du CEIM. Cette rotation est responsable du transport du terrane d'Anarak-Jandak vers sa position actuelle en Iran Central, et de la dislocation de Terranes de moindre importance, comme le bloc de Posht-e Badam. Depuis le Miocène supérieur, et à la suite de la collision entre l'Arabie et l'Iran, le ternane d'Anarak-Jandak a subi des déformations liées à l'activité d'une zone de cisaillement dextre parallèle à la suture du Zagros, à l'arrière de l'arc magmatique d'Uromieh-Dokhtar. Résumé large public Le Microcontinent Centre-Est Iranien occupe une position géologique clé au centre de l'Iran. Les différentes unités qui le composent, reliées jusqu'à présent à des épisodes orogéniques d'âge Précambrien à Paléozoïque inférieur, sont maintenant rajeunies et liés à la fermeture de l'océean Paléotéthys. Leur histoire commence par un épisode de rifting d'âge Ordovicien supérieur à Dévonien inférieur, pour se terminer au Trias par la collision des- blocs Cimmériens, dérivés du Gondwana, avec le Bloc du Turan d'affinité asiatique. Dans la marge active asiatique de la Paléotéthys, nous avons daté les restes d'un océan marginal à 387±0.11 Ma. Ce complexe d'accrétion a été métamorphisé au cours de la réaccrétion de la ceinture granitique d'Airekan, d'âge Cambrien inférieur (549±15 Ma), qui affleure aujourd'hui à l'extrémité nord-ouest du « terrane » d'Anarak-Jandak correspondant à la plus grande partie de la région étudiée. Le matériel issu de l'arc magmatique de la Paléotéthys est très bien préservé et daté du Dévonien supérieur-Carbonifère. Pendant l'intervalle Paléozoïque supérieur-Trias, la région a été soumise à un régime extensif de type bassin d'arrière-arc, dont un témoin pourrait être la ceinture ophiolitique d'Arusan, comparable aux écailles ophiolitiques d'Aghdarband au nord-est de l'Iran. Cet ensemble métamorphique est recoupé par des granites datés à 215±15 Ma. La subduction vers le nord de l'océan Paléotéthys depuis le Paléozoïque supérieur jusqu'au Trias, a permis l'accumulation de grandes quantités de matériel océanique dans la zone de subduction. Par exemple, une succession de volcans sous-marins, entrés en collision avec le prisme d'accrétion, est à l'origine d'un léger métamorphisme de type HP qui affecte ces séries (280 à 230 Ma). Quant au prisme d'accrétion de Doshakh, d'âge essentiellement Permien supérieur, il a été mis en place le long de la marge continentale et métamorphisé dans le faciès schiste vert. La fermeture de la Paléotéthys s'enregistre finalement par la sédimentation dans le bassin d'avant pays du flysch de Bayazeh, d'âge Triasique. Dans la région de Yazd, on trouve les témoins de la marge passive Cimmérienne, la sédimentation syn-rift Silurienne à Dévonienne inférieure a été interrompue pendant l'intervalle Trias moyen-Trias supérieur, marqué par la flexuration de la marge passive lorsqu'elle rentra en collision avec la marge active asiatique. Cet événement est scellé par des dépôts molassique à charbon du Lias. Le «terrane» d'Anarak-Jandak, probablement situé à l'origine entre le Kopeh Dagh et la plate-forme nord Afghane, s'est complètement détaché de cette région au début du Crétacé supérieur lors de l'ouverture d'un bassin d'arrière-arc, engendré, cette fois, par la subduction de l'océan Néotéthys situé au sud des blocs cimmériens. Des preuves de cet événement se retrouvent dans les séries syn-rift, puis de marge passive de Khour. Les ophiolites de Nain et de Sabzevar sont interprétées comme un témoin de l'existence de ce bassin d'arrière-arc. Dans l'intervalle Eocène-Oligocène, l'indentation de l'Eurasie par la plaque indienne a été contemporaine de la rotation horaire de fragments de l'ancien microcontinent centre-Iranien. Cette rotation de près de 90° est responsable du transport du « terrane » d'Anarak-Jandak vers sa position actuelle. Abstract The Anarak-Jandaq terrane occupies a strategic geological situation at the north-western part of the Central-East Iranian Microcontinent (CEIM) and in connection with the Great Kavir Block and Sanandaj-Sirjan metamorphic belt. Our recent findings redefine the origin of these mentioned areas so far attributed to the Precambrian-Early Palaeozoic orogenic episodes, to be now directly related to the tectonic evolution of the Palaeo-Tethys Ocean, commenced by Late Ordovician-Early Devonian rifting events and terminated in the Triassic by the Eocimmerian tectonic event due to the collision of the Cimmerian blocks with the Asiatic Turan block. The most distributed metamorphic unit that is exposed from the south-west of Jandaq to the Anarak and Kaboudan areas is a thick and fine grain siliciclastic sequence accompanied by marginal-sea-basin ophiolitic blocks including basalt-gabbro association with supra-subduction-geochemical signature. These gabbros in the Nakhlak area were dated by U/Pb method at 387.6 ± 0.11 Ma and the metamorphic pelitic rocks yielded a range of 320 to 333 Ma muscovite-cooling ages based on 40Ar/39 Ar method. This "Variscan" accretionary complex was metamorphosed in greenschist-amphibolite facies during accretion to the Lower Cambrian Airekan granitic belt (549 ± 15 Ma by U/Pb method) that crops out at the northwestern edge of the Anarak-Jandaq terrane. Continued northward subduction of the Palaeo-Tethys Ocean during the entire Late Palaeozoic-Middle Triassic brought huge amount of oceanic material to the subduction zone. One chain of Carboniferous-Triassic oceanic rises and seamounts (the Anarak, Kaboudan, and Meraji Seamounts) obliquely collided with the accretionary wedge and created a mild HP metamorphic event (280-230 Ma based on 40Ar/39Ar results). Bimodal magmatism of the Chah Gorbeh area is characterized by a 262 Ma trondjemite-gabbro as well as pillow alkalibasalts-rhyolites which intruded the Anarak ophiolite when it was being emplaced within the inner-wall trench. The mainly Late Permian-Triassic Doshakh wedge was accreted along the continent and metamorphosed under lower greenschist facies and the probable Triassic Bayazeh flysch filled the foreland basin during the final closure. The Palaeo-Tethys magmatic arc products have been well preserved in the Late Devonian-Carboniferous Godar-e-Siah intra-arc deposits and the Triassic Nakhlak fore-arc succession. During the Late Palaeozoic-Triassic times, the Jandaq area has been affected by back-arc extension and probably the Arusan ophiolitic belt is the remnant of this narrow basin comparable to the Aqdarband ophiolitic remnant in north-east Iran. This metamorphic belt was intruded by 215 ± 15 Ma arc to collisional granites. In the passive margin of the Cimmerian block, on the Yazd region, the Silurian-Early Devonian syn-rift succession as well as the nearly continuous Upper Palaeozoic platform-type deposition was interrupted during the Middle to Late Triassic time, local erosion down to Devonian levels may be related to flexural bulge erosion. The collision event was not so strong to generate intensive deformation but was accompanied by some nappe thrusting onto the passive margin. It is finally unconformably covered by Liassic continental molassic deposits. Related to the onset of Neo-Tethyan back-arc opening in Early Jurassic to Mid-Eocene times, six periods of extensional-compressional events have differently influenced an elongated area, extending from the West Black Sea to Pamir. The Anarak-Jandaq terrane which was situated somewhere in this affected area, probably between the Kopeh Dagh and North Afghan platform, was completely detached from its source at the beginning of the Late Cretaceous
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Combining data from police statistics and crime victim surveys, this article analyses the evolution of crime in Western Europe from 1988 to 2007. The results show that there is no general drop in crime. Property offences and homicide have been decreasing since the mid 1990s, while violent and drug offences have increased during the period under study. These trends highlight the limits of the explanations to the crime drop in the United States, which are based on the premise of a correlation in the evolution of all offences. The drop in property offences seems related to changes in the socioeconomic situation in Europe as well as to increases in security measures in households, and the reinforcement of private security. The increase in violent offences can be explained by the combination of several factors, including changes in youth's free time provoked by the development of the Internet, changing demographics, and the rise of episodic heavy alcohol consumption and street gangs.
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Among the large number of granitic intrusions within the Dora-Maira massif, several main types can be distinguished. In this study we report field, petrographic and geochemical investigations as well as zircon typology and conventional U-Pb zircon dating of plutons representing these types. The main results are as follows: the Punta Muret augengneiss is a polymetamorphosed peraluminous granite of anatectic origin. It is 457 +/- 2 Ma old and represents one of the numerous Caledonian orthogneisses of the Alpine basement. All other dated granites are of Late Variscan age. The Cavour leucogranite is an evolved granite of probably calc-alkaline affiliation, dated at 304 +/- 2 Ma. The dioritic and granodioritic facies of the Malanaggio diorite (auct.) are typical calc-alkaline rocks, whose respective age of 290 +/- 2 and 288 +/- 2 Ma overlap within errors. The Sangone and Freidour granite types have very similar alkali-calcic characteristics; their ages are poorly constrained between 267-279 and 268-283 Ma, respectively. The new data for the Dora-Maira granites are in keeping with models of the overall evolution of the Late- to Post-Variscan magmatism in the Alpine area in terms of age distribution and progressive geochemical evolution towards alkaline melts. In a first approximation, granitic rocks across the Variscan belt seem to be increasingly younger towards the internal (southern) parts of the orogen. A Carboniferous, distensive Basin and Range situation is thought to be responsible for the magmatic activity. This tectonic context is comparable to the back-are opening of an active continental margin. The observed southward migration of the magmatism could be linked to the roll-back of the subducting Paleotethyan oceanic plate along the Variscan cordillera.
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Computed tomography (CT) is used increasingly to measure liver volume in patients undergoing evaluation for transplantation or resection. This study is designed to determine a formula predicting total liver volume (TLV) based on body surface area (BSA) or body weight in Western adults. TLV was measured in 292 patients from four Western centers. Liver volumes were calculated from helical computed tomographic scans obtained for conditions unrelated to the hepatobiliary system. BSA was calculated based on height and weight. Each center used a different established method of three-dimensional volume reconstruction. Using regression analysis, measurements were compared, and formulas correlating BSA or body weight to TLV were established. A linear regression formula to estimate TLV based on BSA was obtained: TLV = -794.41 + 1,267.28 x BSA (square meters; r(2) = 0.46; P <.0001). A formula based on patient weight also was derived: TLV = 191.80 + 18.51 x weight (kilograms; r(2) = 0.49; P <.0001). The newly derived TLV formula based on BSA was compared with previously reported formulas. The application of a formula obtained from healthy Japanese individuals underestimated TLV. Two formulas derived from autopsy data for Western populations were similar to the newly derived BSA formula, with a slight overestimation of TLV. In conclusion, hepatic three-dimensional volume reconstruction based on helical CT predicts TLV based on BSA or body weight. The new formulas derived from this correlation should contribute to the estimation of TLV before liver transplantation or major hepatic resection.
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Audit report on the Great River Regional Waste Authority for the years ended June 30, 2005 and 2006.
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1 Insect pests, biological invasions and climate change are considered to representmajor threats to biodiversity, ecosystem functioning, agriculture and forestry.Deriving hypothesis of contemporary and/or future potential distributions of insectpests and invasive species is becoming an important tool for predicting the spatialstructure of potential threats.2 The western corn rootworm (WCR) Diabrotica virgifera virgifera LeConte is apest of maize in North America that has invaded Europe in recent years, resultingin economic costs in terms of maize yields in both continents. The present studyaimed to estimate the dynamics of potential areas of invasion by the WCR under aclimate change scenario in the Northern Hemisphere. The areas at risk under thisscenario were assessed by comparing, using complementary approaches, the spatialprojections of current and future areas of climatic favourability of the WCR. Spatialhypothesis were generated with respect to the presence records in the native rangeof the WCR and physiological thresholds from previous empirical studies.3 We used a previously developed protocol specifically designed to estimatethe climatic favourability of the WCR. We selected the most biologicallyrelevant climatic predictors and then used multidimensional envelope (MDE) andMahalanobis distances (MD) approaches to derive potential distributions for currentand future climatic conditions.4 The results obtained showed a northward advancement of the upper physiologicallimit as a result of climate change, which might increase the strength of outbreaksat higher latitudes. In addition, both MDE and MD outputs predict the stability ofclimatic favourability for the WCR in the core of the already invaded area in Europe,which suggests that this zone would continue to experience damage from this pestin Europe.
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Mineral dust aerosols recently collected at the high-altitude Jungfraujoch research station (46 degrees 33'51 `' N, 7 degrees 59'06 `' E; 3580 m a.s.l.) were compared to mineral dust deposited at the Colle Gnifetti glacier (45 degrees 52'50 `' N, 7 degrees 52'33 `' E; 4455 m a.s.l.) over the last millennium. Radiogenic isotope signatures and backward trajectories analyses indicate that major dust sources are situated in the north-central to north-western part of the Saharan desert. Less radiogenic Sr isotopic compositions of PM10 aerosols and of mineral particles deposited during periods of low dust transfer likely result from the enhancement of the background chemically-weathered Saharan source. Saharan dust mobilization and transport were relatively reduced during the second part of the Little Ice Age (ca. 1690-1870) except within the greatest Saharan dust event deposited around 1770. After ca. 1870, sustained dust deposition suggests that increased mineral dust transport over the Alps during the last century could be due to stronger spring/summer North Atlantic southwesterlies and drier winters in North Africa. On the other hand, increasing carbonaceous particle emissions from fossil fuel combustion combined to a higher lead enrichment factor point to concomitant anthropogenic sources of particulate pollutants reaching high-altitude European glaciers during the last century.
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Ectoparasites are common in most bird species, but experimental evidence of their effects on life-history traits is scarce. We investigated experimentally the effects of the hematophagous hen flea (Ceratophyllus gallinae) on timing of reproduction, nest-site choice, nest desertion, clutch size, and hatching success in the great tit (Parus major). When great tits were offered a choice on their territory between an infested and a parasite-free nest-box, they chose the one without parasites. When there was no choice, the great tits in a territory containing an infested nest-box delayed laying the clutch by 11 days as compared with the birds that were offered a parasite-free nesting opportunity. The finding that there was no difference in phenotypic traits related to dominance between the birds nesting in infested boxes and birds nesting in parasite-free boxes suggests that the delay is not imposed by social dominance. Nest desertion between laying and shortly after hatching was significandy higher in infested nests. There was no difference between infested and parasite-free nests in clutch size, but hatching success and hence brood size at hatching were significantly smaller in infested nests. Nest-box studies of great tits have been seminal in the development of evolutionary, ecological, and behavioral theory, but recently a polemic has arisen in the literature about the validity of the conclusions drawn from nest-box studies where the naturally occurring, detrimental ectoparasites are eliminated by the routine removal of old nests between breeding seasons. Our study suggests that this criticism is valid and that the evaluation of the effects of ectoparasites may improve our understanding of behavioral traits, life-history traits, or population dynamics
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Since its inception, a most distinctive (and controversial) feature of the ECB monetary policy strategy has been its emphasis on money and monetary analysis, which constitute the basis of the so-called monetary pillar. The present paper examines the performance of the monetary pillar around the recent financial crisis episode, and discusses its prospects in light of the renewed emphasis on financial stability and the need for enhanced macro-prudential policies.