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61.
The research concerns the Tiber delta area, about 3 km far from the present seacoast, where the remains of the ancient harbour of Rome are located. In 42 AD, Claudius started the construction of the harbour and Nero completed it in 64 AD. Then, the emperor Trajan went on to add a hexagonal basin to the former structure, which had gradually silted up. The imperial harbour was connected to the Tiber River and ultimately to the city of Rome through the Trajan channel. During the imperial period, most of the supplies imported from the Mediterranean provinces reached the city of Rome through Portus.  相似文献   
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This paper explores the meaning and use of colonoware ceramics recovered from six archaeological sites dating from the nineteenth-century at Manassas, Virginia. Americans, both free and enslaved, occupied this landscape. Archaeological investigations have recovered colonoware at some nineteenth-century domestic sites but not others. The occurrence of colonoware at these sites is patterned: colonoware in nineteenth-century Manassas was not an “ethnic” marker denoting peoples of African descent, but rather a social marker that distinguished enslaved people from free. People of free and enslaved status attributed negative connotations to colonoware. Enslaved servants employed colonoware out of economic necessity, not as a way to express ethnicity.  相似文献   
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We report the recovery of short fragments of PCR amplifiable ancient DNA from exoskeletal fragments of the grain weevil Sitophilus granarius (L.) extracted from Roman and medieval deposits in Northern England. If DNA preservation in archaeological insect remains is widespread then many applications in the spheres of evolutionary studies and archaeology can be conceived, some of which are outlined.  相似文献   
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The role of raw material quality in Oldowan technology has not been fully explored. There are numerous studies suggesting Oldowan hominins preferred certain types of stone for artifact manufacture. Previous studies of the artifact assemblage from the early Pliocene Oldowan locality of Kanjera South (South Rachuonyo District, Kenya) show that raw material selection and transport was an important aspect of Late Pliocene hominin adaptations. Yet the exact properties of stones that hominins were selecting remain enigmatic. Two potentially important features of artifact raw material are durability and fracture predictability. We investigate fracture predictability through mechanical tests of stone and investigations of the affect of stone properties on fracture patterns in archaeological collections. We investigate stone durability with actualistic studies of edge attrition combined with further mechanical tests of various lithologies. Oldowan hominins at Kanjera appear to have selected raw materials based on their durability. The ability for a stone to fracture consistently does not appear to be as important in hominin toolstone preference as previously assumed. Hominins that produced the assemblages at Kanjera South appear to have incorporated an extensive understanding of various attributes of raw material in the transport and production of stone artifacts. When combined with previous research on the transport patterns at Kanjera, the results of this study provide evidence for a more complex raw material acquisition strategy than has previously been suggested for Late Pliocene Oldowan hominins.  相似文献   
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Mentally ill individuals have always smoked at high rates and continue to do so, despite public health efforts to encourage smoking cessation. In the last half century, the tobacco industry became interested in this connection, and conducted and supported psychiatric and basic science research on the mental health implications of smoking, long before most mental health professionals outside the industry investigated this issue. Initially, representatives of tobacco industry research organizations supported genetics and psychosomatic research to try to disprove findings that smoking causes lung cancer. Tobacco industry research leaders engaged with investigators because of shared priorities and interests in the brain effects of nicotine. By the 1980s, collaborative funding programs and individual company research and development teams engaged in intramural and extramural basic science studies on the neuropharmacology of nicotine. When mental health researchers outside the industry became interested in the issue of the mentally ill and smoking in the mid-1990s, they increasingly explained it in terms of a disease of nicotine addiction. Both the idea that smoking/nicotine does something positive for the mentally ill and the conclusion that it is the result of nicotine dependence have the potential to support corporate agendas (tobacco or pharmaceutical).  相似文献   
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Popular cultural convention holds that, for those with enough gumption, the American frontier was a land of unparalleled opportunity. However, careful research throws doubt on the universality of this convention. Thus, the authors explore factors that increase or decrease opportunities for upward mobility in frontier towns. The authors' longitudinal study of late nineteenth century silver prospectors in Gothic, Colorado, demonstrates that while enthusiastic prospecting in Gothic did not lead to upward social mobility, it did provide enhanced reproductive opportunities.  相似文献   
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