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Trovato F 《Journal of biosocial science》2001,33(1):67-86
Indigenous populations in New World nations share the common experience of culture contact with outsiders and a prolonged history of prejudice and discrimination. This historical reality continues to have profound effects on their well-being, as demonstrated by their relative disadvantages in socioeconomic status on the one hand, and in their delayed demographic and epidemiological transitions on the other. In this study one aspect of aboriginals' epidemiological situation is examined: their mortality experience between the early 1980s and early 1990s. The groups studied are the Canadian Indians, the American Indians and the New Zealand Maori (data for Australian Aboriginals could not be obtained). Cause-specific death rates of these three minority groups are compared with those of their respective non-indigenous populations using multivariate log-linear competing risks models. The empirical results are consistent with the proposition that the contemporary mortality conditions of these three minorities reflect, in varying degrees, problems associated with poverty, marginalization and social disorganization. Of the three minority groups, the Canadian Indians appear to suffer more from these types of conditions, and the Maori the least. 相似文献
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Late Quaternary biomes of Canada and the eastern United States 总被引:6,自引:1,他引:6
John W. Williams Thompson Webb III Pierre H. Richard Paige Newby 《Journal of Biogeography》2000,27(3):585-607
Pollen data have been used to construct biome maps for today, 6000 14C yr bp and 18,000 14C yr bp for Canada and the eastern United States. The inferred modern biome distributions agree well with independent reconstructions of North American vegetation prior to European settlement. Some discrepancies between the pollen data and the modern potential vegetation are caused by post‐settlement clearing of the landscape and the consequent increase of herbaceous types in the recent pollen record. Biome distributions at 6000 14C yr bp reflected the warmer and drier conditions then prevalent in the continental interior, but the overall position of biomes was similar to that of today. The boreal treeline in North America was not significantly north of its present position, in contrast to the 100–200 km shift reported for Siberia. At the last glacial maximum (18,000 14C yr bp ), steppe and tundra were prevalent in the Midwest and north‐western Canada, and coniferous forests and woodlands grew in eastern North America. The open vegetation at 18,000 14C yr bp was probably due to drier conditions and/or lower concentrations of atmospheric CO2. The composition and physical structure of biomes is not constant over time. Mid‐Holocene biomes were similar in structure to those of today, but shifts in the relative importance of individual plant functional types are large enough that the physical properties of biomes, such as albedo, canopy conductance and surface roughness, are likely to have varied even during the Holocene. Last glacial maximum biomes were structurally different from their modern counterparts. The biome maps therefore may obscure significant vegetational changes in space and time during the late Quaternary. The difference between the highest and next highest affinity scores for each sample measures how strongly affinity scores discriminate among biomes. For many biomes, the difference is not large, and affinity score ties are not uncommon, highlighting the importance of tie‐break procedures when using the biomization method. 相似文献
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This article, 'Reflections on the United States Military 1941-1987' written by my grandmother, Mary Mandels, illustrates her
passion for life. Her outreach article was considered most appropriate for publication in this forum. Her career activities
are outlined in the prior article 'Mary Elizabeth Hickox Mandels, 90, Bioenergy Leader' while her accomplishments were fully
recognized, for instance, nationally through the American Chemical Society and through her induction into the Hall of Fame
at the US Army Soldier Systems Center in Natick, Massachusetts. As illustrated, along with Dr Elwyn Reese at Natick's Pioneering
Research Laboratory, she headed a bioengineering group that is particularly remembered for developing a process for the enzymatic
conversion of waste cellulosic biomass into soluble sugars that could be fermented to ethanol for an alternate liquid fuel
(gasohol). This technology remains a subject of interest with growing environmental concerns and an oil shortage crisis. 相似文献
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A considerable number of institutions offer courses in restoration ecology and its application, ecological restoration. We quantified the scope and structure of introductory restoration courses at 67 post‐secondary institutions by reviewing institutional course catalogs and course syllabi. Most courses were available at Research‐level institutions. More than half of the courses were offered within departments that focused on natural resource management, and were required or optional in a degree program. Most courses were taught in classroom settings during the academic year and were geared toward advanced students. Course titles suggested an emphasis on the science of restoration ecology over the practice of ecological restoration, and learning objectives focused primarily on concepts and less on skills and attitudes. Assessment was largely via conventional methods, notably exams. Many courses assigned readings from the primary literature; there was little consensus in terms of text selection. We conclude that restoration is being presented to students as an advanced undertaking and in largely theoretical terms. Although we were unable to consider other important elements such as thematic content, class size, or pedagogical method, our study provides a baseline assessment of introductory restoration courses that can be used to evaluate changes in restoration education or opportunities for restoration education in other countries. These results can inform the development of new introductory restoration courses, and raise important considerations in light of the development of a Practitioners' Certification Program by the Society for Ecological Restoration. 相似文献
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Gene H. Albrecht 《American journal of physical anthropology》1982,57(1):77-97
A mail survey was completed of the nonhuman primate skeletal collections (excluding tupaiids) housed in United States and Canadian museums, universities, and other institutions. Survey results are reported by genus for both skulls and postcrania without regard for age or sex. The survey emphasized specimens of wild-caught primates but institutional personnel were not always able to separate animals which died in captivity. Responses were received from 157 of the 212 institutions to which questionnaires were sent. Of those who returned the questionnaires, 75 institutions have wild-caught, nonhuman primate skeletal materials in their collections. Institutions that have either no nonhuman primate skeletal materials (50) or only the remains of captive animals (36) are listed separately. The total number of specimens reported exeeds 21,000 skulls and 6,400 postcrania. 相似文献
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JOHN E. MCDONALD JR. 《The Journal of wildlife management》2008,72(7):1461-1462
Abstract The southern extent of the range of Canada lynx (Lynx canadensis) extends into the contiguous United States in locations from Washington State in the West to northern Maine in the East. Lynx persist in various habitats across this range from high-elevation wilderness to intensively managed industrial forests. Lynx habitat use at the species' southern range boundary was poorly understood before the species was listed as Threatened under the Endangered Species Act in 2000, because most research had been conducted in boreal forest. The papers in this special section outline a variety of questions regarding lynx populations at the southern extent of their range, address topics on lynx space use and denning habitat, and provide generally consistent results in terms of features important to lynx habitat use despite the wide variation in specific habitats among the study areas. 相似文献
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Elizabeth Elliot-Meisel 《Ocean Development & International Law》2013,44(2):204-232
The issue of the status of the Northwest Passage has ebbed and flowed in U.S.-Canada relations for decades, but the effect of global warming in the Arctic has moved this issue from the largely academic and legalistic realms to the forefront of bilateral (and international) relations. Intimately linked to Canadian nationalism, U.S. adherence to the doctrine of freedom of the seas, and to politics in both nations, the opposing positions held by the two states can no longer afford to be implacably held. Rather, it is time to put pride and politics aside and return to the “special relationship” between Canada and the United States in order to effect meaningful and mutually beneficial continental security. 相似文献
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Garth T. Hickle 《Journal of Industrial Ecology》2013,17(2):249-261
This article analyzes the policy choices and programmatic elements of extended producer responsibility (EPR) as implemented in the United States and Canada. The article traces the historical development of EPR in each country and defines common features of EPR in each nation. The U.S. states and the Canadian provinces have assumed the primary role, rather than the federal governments, for enacting producer responsibility requirements in their respective countries. However, the paths taken demonstrate several fundamental differences, including the prevalence of individual versus collective responsibility and the financing mechanisms implemented for EPR. Given the deepening experience with EPR and the breadth of its application to a widening array of products in the United States, the Canadian model for EPR is starting to receive more examination from policy makers in the United States, indicating that the policy and programmatic differences between the two nations may eventually be narrowing. The comparative policy analysis is illustrated through the lens of EPR regulatory efforts for waste electronics, with particular profiles of the programs in the State of Minnesota and Province of Ontario. Both approaches broadly reflect many of the policy considerations and governance and programmatic themes that dominate EPR programs in each country. Finally, the article offers recommendations for collaborative work between the United States and Canada to explore consistency between programs and other complementary strategies to support producer responsibility activities. 相似文献
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At present knowledge of fungal biodiversity in North America is scattered in diverse sources ranging from well-reviewed, comprehensive databases to unedited databases of reports from the literature, information on file cards, and uncomputerized reference collections. Resources available electronically were used to determine their relative importance in evaluating the plant-associated fungi known from the United States and to a lesser extent Canada. The results demonstrate that the literature provides the greatest information but that reference collections in the US National Fungus Collections contribute between 22–31% additional data. Little overlap exists between fungi isolated as endophytes and those reported in the literature or as reference collections. Eighty to 100% of the plant-associated fungi reported from Canada are accounted for in comprehensive resources for the United States. A comprehensive database of plant-associated fungi in Canada, the United States, and eventually Mexico would serve as a valuable resource for those making plant quarantine decisions. 相似文献
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Reviewing published coccinellid surveys we found that the number of adventive species has increased steadily over the last
century while the average proportion of native individuals has remained fairly constant until 1987 followed by a rapid decrease
between 1987 and 2006. Seven long-term studies indicated that the total density of coccinellids increased by an average of
14% following establishment of adventive species, but this increase was not significant and in 4 of 7 cases the total density
of coccinellids actually decreased following establishment. Similarly, no significant difference was found in comparisons
of diversity across all studies. These results illustrate that even with multiple long-term data sets it is currently difficult
to make any general conclusions regarding the impact adventive coccinellids have had on native coccinellid assemblages. However,
it is clear that specific systems and species have seen major shifts in recent years. For example, adventives have become
the dominant species in a third of the assemblages where they are found. Focusing on two formerly common native species, Adalia bipunctata and Coccinella novemnotata, we show they have become rare in their former ranges and discuss potential explanations for this phenomenon. 相似文献