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931.
Roads designed by civil or military engineers for animal-drawn vehicles before the arrival of the railways constituted an essential factor for the movement of goods and people and for the economy and trade in different countries. The improvement in road construction techniques over the 18th and 19th centuries, following the creation of the first civil engineering colleges and institutions, allowed greater transportation at diminishing cost. Despite its significance, this heritage has received comparatively little attention from industrial archaeologists. As such, the object of the present article is to provide an overview of the development in road planning and construction in Spain over the 18th and 19th centuries, in order to demonstrate the historical and technological value of these roads. The article also presents two sections of Spanish roads corresponding to the start and end of the study period, and identifies some of the main archaeological elements dating to their time of construction that prove the evolution in road technology. This process has made it possible to create an inventory which incorporates the main elements that characterise this type of infrastructure.  相似文献   
932.
ABSTRACT

Once considered a marginal side-story to the Fairbank-inspired narrative of an agrarian-centered, land-bound China, Chinese maritime history has received increasing attention in the United States as a research field in its own right. Through sustained engagement with trends in regional, comparative, military, and global histories, and dialogue with European and Asian academia, the efforts of several generations of scholars after Fairbank have slowly broken down his paradigm. Studies of maritime China are increasingly showing a broad, integrated maritime East Asian region comprising the seas and their littoral from the Sea of Japan to the Strait of Melaka. This article surveys the historiographical development of the field. It also highlights my work-in-progress on autonomous overseas Chinese polities along the Gulf of Siam littoral in mainland Southeast Asia during the eighteenth century as one possible future path for the study of maritime Chinese history.  相似文献   
933.
ABSTRACT The immunological identification of species-specific blood proteins in skeletal remains has an important role in the reconstruction of ancient dietary, ritual and domestic behaviour. However, which protein provides the most suitable target for such work has not been considered previously, and the present investigation was carried out on human bone to assess the relative merits of IgG and albumin. Extracts of bone from 31 individuals (from the English Civil War, medieval, Early Saxon, Roman, Iron Age and Bronze Age periods) were tested by an enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies. Albumin was detected in 23 of the 31 skeletons, including those from the Iron and Bronze Ages, whereas IgG was identified in only one; this difference was very highly significant (P < 0.0005, χ2 30.0). The better detection rate for albumin was thought to be due to its higher original blood level, inherent differences in survival pattern being considered unlikely. Testing the same extract for both proteins in the same assay system ensured that any effects due to soil factors, burial conditions, physical integrity of the bone, chronological age, amount of original specimen, method of analysis and type of reagent were the same for each part of the study, thus permitting a valid comparison of antigen survival to be made. Control samples, including fresh and ancient animal bone extracts and human and animal sera, confirmed that the results were consistent and specific, with no cross-reactivity between human and animal material, and that as little as 10 ng of protein was detectable. In summary, the investigation compared the suitability of IgG and albumin for osteoarchaeological studies using a highly specific, sensitive and versatile ELISA; the results showed that albumin was a far better target molecule for such work and that it can survive in ancient bone for long periods of time.  相似文献   
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