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61.
Thomas R 《Journal of regional science》1999,39(2):359-385
The persistence of HIV/AIDS has seen a revival of academic interest in the development of modeling systems to assist understanding the population dynamics of this infection. Moreover, it has become increasingly recognized that a key component of these systems for interpreting disease prevention is their reproduction rate, which provides an indication of whether an epidemic might start in a community described by a particular set of epidemiological characteristics. The properties of these rates have been explored in detail for models of a single risk behavior but not for multiregion formats that allow for the transfer of infection between geographical units. Therefore, in this paper I derive reproduction rates for a multiregion HIV/AIDS model together with their associated critical thresholds that estimate the minimum population of susceptibles necessary for an epidemic to begin. These statistics are interpreted for a simplified global setting representing regional variations in the potential onset of HIV/AIDS. In the discussion I examine the potential applicability of these results to understanding HIV/AIDS prevention. 相似文献
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Street Martin Baales Michael Cziesla Erwin Hartz Sönke Heinen Martin Jöris Olaf Koch Ingrid Pasda Clemens Terberger Thomas Vollbrecht Jürgen 《Journal of World Prehistory》2001,15(4):365-453
During the past decade research into the German Final Paleolithic and Mesolithic has experienced an important revival. One clear sign of this renewed interest in the periods are the annual meetings of the Arbeitsgruppe Mesolithikum (Mesolithic Working Group) which have taken place every spring since 1992. At these meetings, which take place at changing venues, topical themes of Final Paleolithic and Mesolithic interest are presented by informal lectures and it is also possible to study regional collections (artifacts, raw materials) at first hand. Numerous contributions were subsequently published together in one volume (Conard and Kind (1998) Aktuelle Forschungen zum Mesolithikum/Current Mesolithic Research, Mo Vince, Tübingen). The present paper intends to complement that collection of papers with a synthesis of developments and perspectives and to present recent research highlights in the German Final Paleolithic and Mesolithic, together with a comprehensive bibliography, to a wider international audience. 相似文献
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E. Tourigny R. Thomas E. Guiry R. Earp A. Allen J. L. Rothenburger D. Lawler M. Nussbaumer 《International Journal of Osteoarchaeology》2016,26(5):818-829
A 19th‐century dog burial uncovered from a historical homelot in Toronto, Canada, provided a unique opportunity to reconstruct the individual's osteobiography. Of particular interest are the dog's very large size and a suite of skeletal pathologies. Recovery of a nearly complete skeleton combined with the use of X‐rays and micro‐computed tomography (micro‐CT) allowed for a discriminating differential diagnoses. Stable isotope analyses were applied to investigate questions of diet. Results reveal an individual who suffered greatly from disease towards the end of his life and hint at its owners attitudes towards dogs. The interdisciplinary approach applied to this case study highlights the potential information obtainable from pet burials. We argue that better analyses and reporting of pet burials will help address research questions targeting broader themes related to human–animal relationships. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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EMERGENCE OF LEAPFROGGING FROM RESIDENTIAL CHOICE WITH ENDOGENOUS GREEN SPACE: ANALYTICAL RESULTS 下载免费PDF全文
Dominique Peeters Geoffrey Caruso Jean Cavailhès Isabelle Thomas Pierre Frankhauser Gilles Vuidel 《Journal of regional science》2015,55(3):491-512
Leapfrog development is a typical form of sprawl. This paper aims at analyzing the existence, size, and persistence of leapfrogging in a dynamic urban economic model with endogenous green amenities. We analyze whether incoming households choose to settle at the fringe of the city or to jump further away depending on their preferences and the structure of the city. We first provide an analytical treatment of the conditions and characteristics under which a first leapfrog occurs and show how the optimal choice is affected by the size of the city, income, commuting costs, as well as the size of the area where green amenities are considered. We then study how further leapfrogging and multiple urban rings may appear and be maintained in the long‐run equilibrium, and how infill processes take place through time. 相似文献
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ABSTRACT We investigate the relationship between income tax rate variation and internal migration for the unique case of Switzerland, whose system of determining tax rates primarily at the community level results in enough variation to permit analysis of their influence on migration. Specifically, using Swiss census data, we analyze migratory responses to tax rate variations for various groups defined by age, education, and nationality/residence permit. The results suggest that young Swiss college graduates are most sensitive to tax rate differences, but the estimated effects are not large enough to offset the revenue‐increasing effect of a rise in tax rate. The migratory responses of foreigners and other age‐education groups are even smaller, and reverse causation seems negligible. 相似文献
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In this paper, we describe and reflect upon our journey through Indigenous online mapping in Canada. This journey has been planned according to an academic goal: assessing the potential of online cartography for decolonial purposes. To reach this goal, we have followed methodological directions provided by Indigenous scholar Linda Tuhiwai Smith to review 18 Indigenous web-mapping sites across Canada. Supported by a series of ten interviews, this content analysis enabled us to sketch some of the contours of contemporary Indigenous cartography. On one hand, Indigenous communities largely control the data that are shared on these websites. They also partially control the way these data are represented through the mobilization of digital storytelling technologies that are better aligned with Indigenous ways of envisioning relationships to places than conventional maps. On the other hand, they do not have much control over the technological aspects of these projects, for which they remain heavily dependent on non-Indigenous partners. Throughout this journey, we noticed that women's voices remained marginal in most of these mapping projects, but we also identified evidence supporting the idea that these voices are starting to play a vital role in the on-going effort of decolonizing mapping processes. 相似文献
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Thomas Lienhard 《Early Medieval Europe》2020,28(1):57-78
The Slavonic Lives of Constantine/Cyril (d. 869) and Methodius (d. 885) are generally considered to have been written shortly after the death of these two saints, and in any case in the ninth century. However, the present article tries to show that this contention is not conclusive. Instead, it argues for a later writing, in the course of the tenth or eleventh centuries, taking into account in particular the authors' use of older Latin sources on the same theme. As a result, the specific information from these two Lives is subject to caution, which has important consequences for the biography of Constantine/Cyril, for the modalities of the papal mission to Moravia, and more generally for the history of the Slavic countries in the ninth century. 相似文献
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