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71.
The use of immunological techniques for identifying the origin of proteins and inferring foodstuffs exploited by prehistoric occupations has been conducted for several decades. Cases of experimental laboratory and archaeological studies have shown the potential of these techniques for reliable results. However, very few of these case studies employ archaeological sites that have excellent preservation and high-resolution spatial contexts between identifiable faunal remains, features, and stone tools. We present an assessment of the identification reliability of one immunological technique, protein radioimmunoassay (pRIA), using faunal remains and stone tools from two sites from arctic and subarctic contexts. The results of this research indicate that, even in contexts with excellent preservation, the identifications produced by the pRIA technique are subject to misidentification and cross-reactions due to diagenetic alteration of proteins. We propose a higher minimum reaction value (percent binding of labeled antibody) that mitigates these effects, and renders the pRIA results more reliable for ancient, poorly preserved organic remains.  相似文献   
72.
This article examines the portrayal of non-North Koreans in North Korean textbooks to assess the influences on the formation of North Korean identity, and how such identity formation is important in Kim Jeong-il's retention of power. This study not only looks closely at textual representations; it also examines how political and ideological changes in North Korea had a critical influence on these texts. The study encompasses both lexico-grammatical analysis and the analysis of textual and visual images, based on an examination of six North Korean language textbooks published from 1954 to 2000. It demonstrates that North Korean identity is defined through the portrayal of non-North Koreans, particularly enemy others. The portrayal of non-North Koreans facilitates the formation of a solid North Korean identity – an identity that entails serving their political leaders, remaining vigilant against threats to their country, and liberating South Koreans from poverty and oppression by America and its puppet states.  相似文献   
73.
Until now, the oldest known human hair was from a 9000-year-old South American mummy. Here we report fossil hairs of probable human origin that exceed that age by about 200,000 years. The hairs have been discovered in a brown hyaena (Parahyaena brunnea) coprolite from Gladysvale cave in South Africa. The coprolite is part of a hyaena latrine preserved in calcified cave sediment dated between 195,000 and 257,000 years ago. This find supports the hypothesis that hyaenas accumulated some of the early hominin remains found in cave sites, and provides a new source of information on Pleistocene mammals in the Sterkfontein Valley.  相似文献   
74.
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   
75.
Research on the neurobiology and pharmacotherapy of attention-deficit/hyperactivity disorder (ADHD) has grown exponentially since 1980. A reasonable question is whether this research has improved our understanding and treatment of ADHD. This article describes relevant developments that took place roughly between 1900 and 1970. During this time, the efficacy of stimulant therapy for the disorder was established and the symptoms of ADHD were linked to many possible nervous system disorders including in the brain-stem, reticular formation, diencephalon, basal ganglia, frontal lobes, and cortex. In 1970, the catecholamine hypothesis of ADHD was proposed. It is concluded that early theories about the neurobiologic basis of ADHD anticipated core ideas of modern theory.  相似文献   
76.
ABSTRACT In research conducted some 20 years ago, we elucidated the starkly lower suburbanization propensities of black households in the Washington, D.C. metropolitan area. The paper showed that simulated closure of large socio‐economic gaps between blacks and whites did little to diminish prevailing high levels of residential segregation or otherwise enhance moves by black households to areas of educational, employment, and housing opportunity. Some two decades later and in the wake of significant urban evolution, this paper assesses anew racial variations in residential location choice. Results of the multinomial logit (MNL) analysis indicate large, persistent racial differentials in intrametropolitan residential location choice. While black location choice in 2000 was relatively more dispersed than in 1980, it remained remarkably concentrated in D.C. and Prince George's County. As in our prior analysis, results showed that large simulated gains in black economic and educational status had little effect on prevailing racial segregation. These findings underscore the ongoing, limited access of black households to schooling, employment, and homeownership opportunities available outside traditional areas of settlement. In marked contrast, the locational choices of Latino and immigrant households bore greater similarity to those of whites and were more sensitive to improvements in socio‐economic status.  相似文献   
77.
Fezzeh Khanom (c. 1835–82), an African woman, was a slave of Sayyed ‘Ali-Mohammad of Shiraz, the Bab. Information about her life can be recovered from various pious Baha'i histories. She was honored, and even venerated by Babis, though she remained subordinate and invisible. The paper makes the encouraging discovery that a history of African slavery in Iran is possible, even at the level of individual biographies. Scholars estimate that between one and two million slaves were exported from Africa to the Indian Ocean trade in the nineteenth century, most to Iranian ports. Some two-thirds of African slaves brought to Iran were women intended as household servants and concubines. An examination of Fezzeh Khanom's life can begin to fill the gaps in our knowledge of enslaved women in Iran. The paper discusses African influences on Iranian culture, especially in wealthy households and in the royal court. The limited value of Western legal distinctions between slavery and freedom when applied to the Muslim world is noted.  相似文献   
78.
This study explores how a scientist's location in science‐based policy networks can affect her policy‐oriented behaviors. In particular, we hypothesize that those scientists who fill structural holes in their networks will be more likely than others to engage in policy‐oriented behaviors. The network data are defined by scientists' coauthorship on policy documents regarding climate change in the Great Lakes. We employ a two‐mode network analysis to identify clusters of scientists who coauthored similar documents, and relative to those clusters, we identify those who fill structural holes by bridging between clusters. We find that those scientists who bridged between clusters were more likely to engage in policy‐oriented behaviors of policy advocacy and advising than were others in the network. This is an example of a link between network location and policy‐oriented behavior indicative of the broader phenomenon of how individuals exert agency, given structural constraints.  相似文献   
79.
Charcoal-tempered pottery is uncommon in North America, but was produced with notable frequency in Northeast Florida from ca. AD 300–600. Thirty-six thin sections of pottery were analyzed by petrographic analysis and compared to 10 clay samples in order to characterize the paste of charcoal-tempered wares in terms of charcoal and mineralogical composition and abundance, assess the number of clay sources used to make the pottery, identify the species of wood represented in charcoal inclusions, and infer techniques of ceramic production. This analysis identified four temper categories, three texture groups, and three distinct clay resources used to make charcoal-tempered pottery, all of which were likely local to Northeast Florida. Identified wood taxa include pine (Pinus sp.), cedar (cf. Juniperus sp.), cypress (cf. Taxodium sp.), and sassafras (Sassafras albidum), with pine suspected to be the most common. These genera of charred wood, which exhibit minimal shrinkage in the samples, along with the prevalence of bone and grog inclusions, indicate that hearth contents were processed as temper, sometimes in combination with quartz sand. Potential reasons for the use of hearth contents as temper are considered.  相似文献   
80.
A panel of geographers debates possible future developments in the Soviet Union in regional and environmental policy, water resource management, agriculture, industry, energy, population, urban growth and planning, transportation, and foreign trade. The present emphasis on modernization of existing plant capacity in cities of the western, more heavily settled regions of the USSR seems destined to continue, although it will be constrained by a growing shortage of industrial labor, declining terms of trade and resource oversupply in increasingly competitive export markets, and the continued resistance of Central Asian populations to urbanization and industrial employment.  相似文献   
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