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This narrative deals with the author's experiences while attending a human trafficking panel at the Pontifical Academy of Social Sciences (PASS) in the Casina Pio IV, Vatican City, 7–21 April 2015.  相似文献   
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We have investigated the survival of PCR-amplifiable mitochondrial and nuclear DNA in a small number of modern and medieval bovine leather samples. The results of this preliminary investigation demonstrate that, while no nuclear DNA can be PCR-amplified from any of the specimens, mitochondrial DNA can be amplified from all samples. To investigate this contrasting pattern of DNA survival further, we have vegetable-tanned cow skin in our own laboratory, and directly assayed the survival of PCR-amplifiable mitochondrial and nuclear DNA at each step of the process. The results indicate that nuclear DNA is reduced to sub-amplifiable levels as a result of the tanning baths, whereas amplifiable mitochondrial DNA survives the complete process. Our results suggest that old and archaeological bovine leather may represent a useful source of genetic information, although this information will most likely be limited to that which can be gained from mitochondrial DNA.  相似文献   
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Osteobiographies were reconstructed from the skeletal remains of four adults from Fort Edmonton, a 19th century trading post of the Canadian fur trade. Three males were Caucasoid and probably ethnic Scots, given the usual origin of fur traders in this region. The lone adult female in the sample was Mongoloid, either Indian or Métis, and likely the ‘country wife’ of a fur trader, since she was buried in the European tradition in the fort cemetery. The cause of death is not discernible from any of the skeletal remains and none of these individuals exhibit any evidence of chronic infectious disease, malnutrition or neoplasia. Trauma, arthritis and other indicators of physical stress do appear, however, and present an opportunity to expand our understanding of the effects of fur trade life on the skeleton. Viewed in the context of historical accounts of life at the fort in the early 19th century, stress markers on the skeletons of three males have led to the conclusion that they were voyageurs who engaged in trading trips by canoe or boat. Lesions of the capsule attachment area at the proximal tibio‐fibular articulation appear unilaterally in two males and may be associated with ‘mushing’ or driving a dog sled in winter. The musculoskeletal lesions on the one preserved female skeleton are consistent with the arduous domestic activities documented at the fort, which include milking cows, churning butter, stirring lye soap, and harvesting grain and root vegetables by hand. Since specific occupations or behaviours cannot be precisely determined from muscular attachment and other stress markers, these interpretations are made cautiously and only in the culture‐historical context of the skeletal sample. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
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ABSTRACT This paper examines the role of the structure of transportation rates in the Weber-Moses triangle model. It shows that, in Zeigler's analysis, the appearance of the price elasticities of demand for inputs actually vanish by a simple application of the envelope theorem. Applying comparative statics analysis, we show when transportation rates are a function of quantity and distance, the assumptions that the production function is homogeneous of degree one and the transportation rates elasticities with respect to quantity and distance are constant are not sufficient to insure that the optimum location is independent of the level of output. This result is significantly different from that obtained by either Miller and Jensen or Zeigler.  相似文献   
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