971 resultados para Ships -- Great Lakes (North America) -- History.


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Water chestnut (Trapa natans L.,sensu lato) is an annual, floating-leaved aquatic plant of temperate and tropical freshwater wetlands, rivers, lakes, ponds, and estuaries. Native to Eurasia and Africa, water chestnut has been widely gathered for its large nutritious seed since the Neolithic and is cultivated for food in Asia. Water chestnut is now a species of conservation concern in Europe and Russia. Introduced to the northeastern United States in the mid-1800s, the spread of water chestnut as a nuisance weed was apparently favored by cultural eutrophication. Water chestnut is considered a pest in the U.S. because it forms extensive, dense beds in lakes, rivers, and freshwater-tidal habitats.

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Covers the history of the study of boring sponges, taxonomy and distributions. Also includes identification of species, descriptions, key, references and plates. (PDF contains 30 pages)

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Before the mass migrations from Ireland in the nineteenth century, earlier waves of migration in the eighteenth century saw significant numbers of people leave Ireland, predominantly from Ulster, to settle in North America. This article, using as its principal data source the Belfast News Letter ( BNL), its letters, advertisements and reports, focuses firstly on reconstructing the late eighteenth-century migration process and voyage, highlighting the barriers represented by the Atlantic Ocean. In addition to the challenges of the sea, there were problems with the ships, the ever-present danger of disease and also threats from other vessels, from privateers to press gangs. The voyage was recognized as a ‘universal dread’, and the risks taken to ‘dare the boist’rous main’ were perhaps not minimized in the pages of the BNL, whose editorial stance was antipathetic to the migration for the potential harm it caused to Ulster by removing so many of its industrious young. The second part of this article goes on to consider the newspaper’s and others’ vested interests in the emigration process, demonstrates how these were manifested in the press and sets the coverage of this very significant early emigration flow within the context of contemporary religious and colonial discourses at a period of very lively transatlantic interactions.

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This archive contains materials relating to the Great Lakes Waterways Development Association. The collection contains correspondence, financial information, clippings, biographical materials, media releases, presentations and publications. The bulk of the materials are correspondence.

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Salmonid proliferative kidney disease (PKD) is caused by the myxozoan Tetracapsuloides bryosalmonae. Given the serious and apparently growing impact of PKD on farmed and wild salmonids, we undertook a phylogeographic study to gain insights into the history of genealogical lineages of T. bryosalmonae in Europe and North America, and to determine if the global expansion of rainbow trout farming has spread the disease. Phylogenetic analyses of internal transcribed spacer 1 sequences revealed a clade composed of all North American sequences plus a subset of Italian and French sequences. High genetic diversity in North America and the absence of genotypes diagnostic of the North American clade in the rest of Europe imply that southern Europe was colonized by immigration from North America; however, sequence divergence suggests that this colonization substantially pre-dated fisheries activities. Furthermore, the lack of southern European lineages in the rest of Europe, despite widespread rainbow trout farming, indicates that T. bryosalmonae is not transported through fisheries activities. This result strikingly contrasts with the commonness of fisheries-related introductions of other pathogens and parasites and indicates that fishes may be dead-end hosts. Our results also demonstrate that European strains of T. bryosalmonae infect and induce PKD in rainbow trout introduced to Europe.

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In a recent study we found that crania from South Amerindian populations on each side of the Andes differ significantly in terms of craniofacial shape. Western populations formed one morphological group, distributed continuously over 14,000 km from the Fuegian archipelago (southern Chile) to the Zulia region (northwestern Venezuela). Easterners formed another group, distributed from the Atlantic Coast up to the eastern foothills of the Andes. This differentiation is further supported by several genetic studies, and indirectly by ecological and archaeological studies. Some authors suggest that this dual biological pattern is consistent with differential rates of gene flow and genetic drift operating on both sides of the Cordillera due to historical reasons. Here we show that such East-West patterning is also observable in North America. We suggest that the ""ecological zones model"" proposed by Dixon, explaining the spread of the early Americans along a Pacific dispersal corridor, combined with the evolution of different population dynamics in both regions, is the most parsimonious mechanism to explain the observed patterns of within- and between-group craniofacial variability. (c) 2007 Elsevier Ltd. All rights reserved.

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An important issue in both Canadian and United States immigration history has been the control of immigration, which includes possible quotas, immigration laws as well as denying entry, and finally, the deportation of immigrants. This paper is based on information that is available on the deportations of 167 people, most of them young adult males. Many assume politics was a key motivation for deportation. However, Finnish Americans were rarely deported for political activities. The paper discusses a few interesting cases of political deportations both during the interwar years, and after the Second World War. The information is mostly based on the correspondence between the authorities in Finland and the United States and Canada, available at the Foreign Ministry Archives in Helsinki, Finland. Special attention is directed to the social and political background of those people and of special interest are the specific reasons, social or health problems, which seem to be the basis of most deportation decisions.

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Acer saccharum Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as being the predisposing and inciting factors in different regions at different times. Some of the most common factors attributed to previous maple dieback episodes were insect defoliation outbreaks, inadequate precipitation, poor soils, atmospheric deposition, fungal pathogens, poor management, or a combination of these. The current sugar maple dieback was evaluated to determine the etiology, severity, and change in dieback on both industry and public lands. A network of 120 sugar maple health evaluation plots was established in the Upper Peninsula, Michigan, northern Wisconsin, and eastern Minnesota and evaluated annually from 2009-2012. Mean sugar maple crown dieback between 2009-2012 was 12.4% (ranging from 0.8-75.5%) across the region. Overall, during the sampling period, mean dieback decreased by 5% but individual plots and trees continued to decline. Relationships were examined between sugar maple dieback and growth, habitat conditions, ownership, climate, soil, foliage nutrients, and the maple pathogen sapstreak. The only statistically significant factor was found to be a high level of forest floor impacts due to exotic earthworm activity. Sugar maple on soils with lower pH had less earthworm impacts, less dieback, and higher growth rates than those on soils more favorable to earthworms. Nutritional status of foliage and soil was correlated with dieback and growth suggesting perturbation of nutrient cycling may be predisposing or contributing to dieback. The previous winter's snowfall totals, length of stay on the ground, and number of days with freezing temperatures had a significant positive relationship to sugar maple growth rates. Sapstreak disease, Ceratocystis virescens, may be contributing to dieback in some stands but was not related to the amount of dieback in the region. The ultimate goal of this research is to help forest managers in the Great Lakes Region prevent, anticipate, reduce, and/or salvage stands with dieback and loss in the future. An improved understanding of the complex etiology associated with sugar maple dieback in the Upper Great Lakes Region is necessary to make appropriate silvicultural decisions. Forest Health education helps increase awareness and proactive forest management in the face of changing forest ecosystems. Lessons are included to assist educators in incorporating forest health into standard biological disciplines at the secondary school curricula.

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The outermost layer of the Earth is broken into tectonic plates whose motions cause earthquakes and volcanism. Much of what we know about the structure of these plates comes from studying the Earth's surface. Seismic waves recorded by the EarthScope Transportable Array, however, show us the internal structure of plates down to 200 km deep and help us understand the relationship between deep structure and the Earth's surface. EarthScope images for the western United States hint at the presence of the mid-depth discontinuities. To better understand these features, Dr. Lekic relates them to the geologic history of the west.

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The performance of reanalysis-driven Canadian Regional Climate Model, version 5 (CRCM5) in reproducing the present climate over the North American COordinated Regional climate Downscaling EXperiment domain for the 1989–2008 period has been assessed in comparison with several observation-based datasets. The model reproduces satisfactorily the near-surface temperature and precipitation characteristics over most part of North America. Coastal and mountainous zones remain problematic: a cold bias (2–6 °C) prevails over Rocky Mountains in summertime and all year-round over Mexico; winter precipitation in mountainous coastal regions is overestimated. The precipitation patterns related to the North American Monsoon are well reproduced, except on its northern limit. The spatial and temporal structure of the Great Plains Low-Level Jet is well reproduced by the model; however, the night-time precipitation maximum in the jet area is underestimated. The performance of CRCM5 was assessed against earlier CRCM versions and other RCMs. CRCM5 is shown to have been substantially improved compared to CRCM3 and CRCM4 in terms of seasonal mean statistics, and to be comparable to other modern RCMs.

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Land-atmosphere coupling and its impact on extreme precipitation and temperature events over North America are studied using the fifth generation of the Canadian Regional Climate Model (CRCM5). To this effect, two 30 year long simulations, spanning the 1981–2010 period, with and without land-atmosphere coupling, have been performed with CRCM5, driven by the European Centre for Medium-Range Weather Forecasts reanalysis at the boundaries. In the coupled simulation, the soil moisture interacts freely with the atmosphere at each time step, while in the uncoupled simulation, soil moisture is replaced with its climatological value computed from the coupled simulation, thus suppressing the soil moisture-atmosphere interactions. Analyses of the coupled and uncoupled simulations, for the summer period, show strong soil moisture-temperature coupling over the Great Plains, consistent with previous studies. The maxima of soil moisture-precipitation coupling is more spread out and covers the semiarid regions of the western U.S. and parts of the Great Plains. However, the strength of soil moisture-precipitation coupling is found to be generally weaker than that of soil moisture-temperature coupling. The study clearly indicates that land-atmosphere coupling increases the interannual variability of the seasonal mean daily maximum temperature in the Great Plains. Land-atmosphere coupling is found to significantly modulate selected temperature extremes such as the number of hot days, frequency, and maximum duration of hot spells over the Great Plains. Results also suggest additional hot spots, where soil moisture modulates extreme events. These hot spots are located in the southeast U.S. for the hot days/hot spells and in the semiarid regions of the western U.S. for extreme wet spells. This study thus demonstrates that climatologically wet/dry regions can become hot spots of land-atmosphere coupling when the soil moisture decreases/increases to an intermediate transitional level where evapotranspiration becomes moisture sensitive and large enough to affect the climate.

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List of Physicians and Surgeons arranged by location, giving post office address with population and location, the School practiced, date and college of graduation, all the existing and extinct medical colleges in North America, with locations, officers, number of professors, lecturers, demonstrators, etc., the various medical societies, penal, reformatory and charitable state institutions, hospitals, sanitariums, dispensaries, asylums and other medical institutions, boards of health, boards of medical examiners, health officers at principal points, the laws of registration and other laws relating to the profession, medical journals with names of editors, frequency of publication and subscription rates, medical libraries, a therapeutic classification of American health resorts, mineral springs, official list of officers of the medical departments of the U.S. Army, Navy and Marine Hospital Service, the U.S. Indian Service, roster of examining surgeons of the U.S. Pension Department, a descriptive sketch of each state, territory and province, embodying such matters as location, boundary, extent in miles and acres, latitude and longitude, statistics relating to climate, temperature, rate of mortality, etc. Full particulars of all national and inter-state associations and societies relating to medicine and surgery, and an INDEX TO THE PHYSICIANS OF THE UNITED STATES. Arranged alphabetically, with the number of the page and column in which the name appears.

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Thermokarst lakes are thought to have been an important source of methane (CH4) during the last deglaciation when atmospheric CH4 concentrations increased rapidly. Here we demonstrate that meltwater from permafrost ice serves as an H source to CH4 production in thermokarst lakes, allowing for region-specific reconstructions of dD-CH4 emissions from Siberian and North American lakes. dD CH4 reflects regionally varying dD values of precipitation incorporated into ground ice at the time of its formation. Late Pleistocene-aged permafrost ground ice was the dominant H source to CH4 production in primary thermokarst lakes, whereas Holocene-aged permafrost ground ice contributed H to CH4 production in later generation lakes. We found that Alaskan thermokarst lake dD-CH4 was higher (-334 ± 17 per mil) than Siberian lake dD-CH4 (-381 ± 18 per mil). Weighted mean dD CH4 values for Beringian lakes ranged from -385 per mil to -382 per mil over the deglacial period. Bottom-up estimates suggest that Beringian thermokarst lakes contributed 15 ± 4 Tg CH4 /yr to the atmosphere during the Younger Dryas and 25 ± 5 Tg CH4 /yr during the Preboreal period. These estimates are supported by independent, top-down isotope mass balance calculations based on ice core dD-CH4 and d13C-CH4 records. Both approaches suggest that thermokarst lakes and boreal wetlands together were important sources of deglacial CH4.

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From ≈11,200 to 8,000 years ago, the Great Plains of North America were populated by small Paleoindian hunting groups with well developed weaponry and the expertise to successfully hunt large mammals, especially mammoths and bison. Mammoths became extinct on the Plains by 11,000 years ago, and, although paleoecological conditions were worsening, their demise may have been hastened by human predation. After this, the main target of the Plains Paleoindian hunters consisted of subspecies of bison, Bison antiquus and Bison occidentalis. As bison populations gradually diminished, apparently because of worsening ecological conditions, by ≈8,000 years ago, human subsistence was forced into a greater dependence on small animal and plant foods. Human paleoecology studies of the Paleoindian time period rely heavily on multidisciplinary efforts. Geomorphologists, botanists, soil scientists, palynologists, biologists, and other specialists aid archaeologists in data recovery and analysis, although, with few exceptions, their contributions are derived from the fringes rather than the mainstream of their disciplines.