993 resultados para Canada-U.S. Border


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It has been established that modern humans were living in the Levant and Africa ca. 100 ka ago. Hitherto, this has contrasted with the situation in China where no unequivocal specimens of this species have been securely dated to more than 30 ka. Here we present the results of stratigraphic studies and U-series dating of the Tongtianyan Cave, the discovery site of the Liujiang hominid, which represents one of the few well-preserved fossils of modern Homo sapiens in China. The human fossils are inferred to come from either a refilling breccia or a primarily deposited gravel-bearing sandy clay layer. In the former case, which is better supported, the fossils would date to at least similar to 68 ka, but more likely to similar to 111-139 ka. Alternatively, they would be older than, similar to 153 ka. Both scenarios would make the Liujiang hominid one of the earliest modem humans in East Asia, possibly contemporaneous with the earliest known representatives from the Levant and Africa. Parallel studies on other Chinese localities have provided supporting evidence for the redating of Liujiang, which may have important implications for, the origin of modem humans. (C) 2002 Elsevier Science Ltd. All rights reserved.

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Este artigo tem como objetivo investigar se as aquisições realizadas por empresas brasileiras fora do País nos últimos 15 anos têm aumentado o desempenho financeiro dessas empresas. Além disso, é realizada uma análise empírica dos fatores determinantes desse sucesso, com base nas teorias institucional, sociocultural e de aprendizagem organizacional. Os resultados indicam que, de fato, as investidas cross border de companhias do Brasil melhoram o desempenho, que é positivamente impactado quando a distância cultural entre os países da adquirida e da adquirente é baixa ou média e quando o ambiente institucional no qual a empresa-alvo se encontra é desenvolvido. Já a relação entre as experiências anteriores das brasileiras em fusões ou aquisições internacionais e o desempenho de uma nova aquisição fora do País segue o formato de U invertido, enfatizando a relevância de se considerar a experiência com fusões e aquisições da empresa compradora além das características institucionais dos seus países-alvo.

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New precise zircon U-Pb ages are proposed for the Triassic-Jurassic (Rhetian-Hettangian) and the Hettangian-Sinemurian boundaries, The ages were obtained by ID-TIMS dating of single chemical-abraded zircons from volcanic ash layers within the Pucara Group, Aramachay Formation in the Utcubamba valley, northern Peru. Ash layers situated between last and first occurrences of boundary-defining ammonites yielded Pb-206/U-238 ages of 201.58 +/- 0.17/0.28 Ma (95% c.l., uncertainties without/with decay constant errors, respectively) for the Triassic-Jurassic and of 199.53 +/- 0.19/0.29 Ma for the Hettangian-Sinemurian boundaries. The former is established on a tuff located 1 m above the last local occurrence of the topmost Triassic genus Choristoceras, and 5 m below the Hettangian genus Psiloceras. The latter sample was obtained from a tuff collected within the Badouxia canadensis beds. Our new ages document total duration of the Hettagian of no more than c. 2 m.y., which has fundamental implications for the interpretation and significance of the ammonite recovery after the topmost Triassic extinction. The U-Pb age is about 0.8 +/- 0.5% older than Ar-40-Ar-39 dates determined on flood basalts of the Central Atlantic Magmatic Province (CAMP). Given the widely accepted hypothesis that inaccuracies in the K-40 decay constants or physical constants create a similar bias between the two dating methods, our new U-Pb zircon age determination for the T/J boundary corroborates the hypothesis that the CAMP was emplaced at the same time and may be responsible for a major climatic turnover and mass extinction. The zircon Pb-206/U-238 age for the T/J boundary is marginally older than the North Mountain Basalt (Newark Supergroup, Nova Scotia, Canada), which has been dated at 201.27 +/- 0.06 Ma [Schoene et al., 2006. Geochim. Cosmochim. Acta 70, 426-445]. It will be important to look for older eruptions of the CAMP and date them precisely by U-Pb techniques while addressing all sources of systematic uncertainty to further test the hypothesis of volcanic induced climate change leading to extinction. Such high-precision, high-accuracy data will be instrumental for constraining the contemporaneity of geological events at a 100 kyr level. (C) 2007 Elsevier B.V. All rights reserved.

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This paper evaluates the global welfare impact of observed levels of migration using a quantitativemulti-sector model of the world economy calibrated to aggregate and firm-level data.Our framework features cross-country labor productivity differences, international trade, remittances,and a heterogeneous workforce. We compare welfare under the observed levels ofmigration to a no-migration counterfactual. In the long run, natives in countries that receiveda lot of migration -such as Canada or Australia- are better o due to greater product varietyavailable in consumption and as intermediate inputs. In the short run the impact of migrationon average welfare in these countries is close to zero, while the skilled and unskilled nativestend to experience welfare changes of opposite signs. The remaining natives in countries withlarge emigration flows -such as Jamaica or El Salvador- are also better off due to migration,but for a different reason: remittances. The welfare impact of observed levels of migration issubstantial, at about 5 to 10% for the main receiving countries and about 10% in countries withlarge incoming remittances. Our results are robust to accounting for imperfect transferabilityof skills, selection into migration, and imperfect substitution between natives and immigrants.

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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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The Second U.S. Regiment of Light Dragoons was formed in January 1812. In March of 1814, it merged with the First U.S. Regiment of Light Dragoons to form the Regiment of Light Dragoons.

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The Fenians were a group intent on securing Irish independence from England. The movement had its origins in Ireland in1857, under the leadership of James Stephens, with the assistance of John O'Mahony, an American who had raised funds for the cause. The American branch of this movement was especially successful, having raised $500 000 and enlisting about 10 000 American Civil War veterans. The group split into two separate factions, one desiring an invasion of Canada and the other preferring an uprising in Ireland. It soon became apparent that an uprising in Ireland was not imminent, and a decision was made to invade Canada. In April, 1866, a raid was launched against New Brunswick. It proved unsuccessful, and another raid was attempted on June 1, 1866, this time in Ridgeway, near Fort Erie, Ontario. The Canadian militiamen were defeated, but the Fenians subsequently withdrew. A third incident occurred on June 7, this time at Missisquoi Bay in Quebec, when the Fenians crossed the border, remained there for 2 days, and withdrew. A failed uprising in Ireland in 1867 signaled the demise of the movement. The Fenian threat helped to promote a sense of union among Canadians and provided an incentive for Confederation.

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An orderly book of the Second Regiment of U.S. Dragoons, New York, dated August 14, 1812-July 29, 1813. The book contains orders pertaining to day-to-day military matters, such as punishments for disobedience, court-martial proceedings, camp rules and regulations, and guidelines for interacting with civilians in the vicinity of the camp. The Regiment was stationed at various locations in upstate New York and Canada, including Greenbush, Albany, Sackets Harbor, Utica, Geneva, Fort Niagara and Fort George. General Henry Dearborn originally commanded the Regiment at Greenbush. Names noted in this book include:E. Beebe, Deputy Adjt. General; William King, Capt. 15th; John Chandler, General ;W. Gamewood, Major ;James Burns, Colonel;John Woodford, Major; Andrew McDowell, Capt.; Abm. Gustis, Major; C.W. Hunter, Brigade Major; Selden, Captain; Holland, Captain; Harris, Captain; Clarkson, Lieutenant; Johnson, Lieutenant; Robert Craig, Adjt.; R.G. Hith, A.A. General. Also included with the orderly book are a monthly return form, a contract for medical services, and a bonus pay voucher for Thomas Blunt. The monthly return form is partially completed and dated January 1813 at Greenbush, New York. It is signed by Captain Jonas Holland. The contract is dated May 20, 1812, between John Dodge, physician and surgeon, and Jonas Holland. The contract describes the services required of the physician and the salary to be paid. The bonus pay voucher is dated April 25, 1813, for $8.00 paid to Thomas Blunt by Captain Jonas Holland for 'enlisting into the army of the United States for five years'.

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The Fenians were a group intent on securing Irish independence from England. The movement had its origins in Ireland in1857, under the leadership of James Stephens, with the assistance of John O'Mahony, an American who had raised funds for the cause. The American branch of this movement was especially successful, having raised $500 000 and enlisting about 10 000 American Civil War veterans. The group split into two separate factions, one desiring an invasion of Canada and the other preferring an uprising in Ireland. It soon became apparent that an uprising in Ireland was not imminent, and a decision was made to invade Canada. In April, 1866, a raid was launched against New Brunswick. It proved unsuccessful, and another raid was attempted on June 1, 1866, this time in Ridgeway, near Fort Erie, Ontario. The Canadian militiamen were defeated, but the Fenians subsequently withdrew. A third incident occurred on June 7, this time at Missisquoi Bay in Quebec, when the Fenians crossed the border, remained there for 2 days, and withdrew. A failed uprising in Ireland in 1867 signaled the demise of the movement. The Fenian threat helped to promote a sense of union among Canadians and provided an incentive for Confederation.

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A selection of slides that appeared in the book "Rum Across the Border" by Allan Seymour Everest. The slides show Overton's Corners Border Station and the large volume of traffic that was inspected, a popular Canadian border spot, The Meridian Hotel and the U.S. Marshall destroying liquor in Rouses Point, N.Y.