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101.
102.
J. Gonda Armand Minard G. W. J. Drewes J. W. de Jong F. B. J. Kuiper 《Indo-Iranian Journal》1963,6(3-4):298-310
103.
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
107.
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
108.
Oxygen is a key parameter in the degradation of archaeological material, but little is known of its dynamics in situ. In this study, 10 optical oxygen sensors placed in a 2 m deep test pit in the cultural deposits at Bryggen in Bergen have monitored oxygen concentrations every half hour for more than a year. It is shown that there is a significant spatial and temporal variation in the oxygen concentration, which is correlated to measured soil characteristics, precipitation, soil water content and degradation of organic material. In these deposits oxygen typically occurs when the air content of the soil exceeds 10–15% vol, while oxygen dissolved in infiltrating rainwater is of less importance for the supply of oxygen in the unsaturated zone. 相似文献
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C. N. Duckworth R. Córdoba de la Llave E. W. Faber D. J. Govantes Edwards J. Henderson 《Archaeometry》2015,57(1):27-50
Twenty‐six samples from domestic assemblages of 9th–12th century Córdoba were subjected to electron microprobe analysis. The results reveal two main compositional types. The first, encountered in 13 of the samples, seems to result from the combination of plant ashes with high‐impurity sand, and has some contemporary parallels from Syria and Egypt. The second type is a lead–soda–silica glass, encountered in a relatively high proportion of the glasses (11 of the 26 sampled), possibly formed by the addition of lead metal to existing glasses and with very few known parallels. These are among a very small number of results available to date on the chemical composition of glasses from medieval Spain, and the presence of a high proportion of lead–soda–silica glasses is particularly interesting, possibly indicating a technological practice unique to, or originating in, the western Muslim world. 相似文献