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131.
132.
In 1932, the U.S. Public Health Service began a study of untreated syphilis among black men in Macon County, Alabama. This project, later known as the Tuskegee Syphilis Study, became one of the most notorious ventures of twentieth-century medicine. Much has been written on it. Historians have suggested that scientific racism strongly influenced the study. But specific links between earlier racial science and the scientific conduct of the study have remained unexplored. The examination in this paper of the concept of a racially determined resistance to syphilis in the nervous system establishes such a link. Discussion of nervous resistance to syphilis appeared in the medical literature in the early twentieth century as a conjecture about the natural inferiority of blacks. White physicians used the concept to interpret racial differences in neurosyphilis as evidence of the rudimentary development of the brain. A small community of African American physicians joined other national experts in syphilis who chose to explain apparent racial differences through alternate mechanisms. But the scientific advisors to the Tuskegee Syphilis Study favored the concept of a racial resistance to neurosyphilis and steered the early design of the study to help to elucidate it. The Tuskegee Syphilis Study was an examination of untreated syphilis, but it also became a demonstration of a putative racial characteristic of syphilis long considered evidence of the natural inferiority of blacks. An examination of the concept of racial nervous resistance and its influence on the research in Macon County helps to define the influence of scientific racism on this notorious medical study.  相似文献   
133.
Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is applied to the study of four samples of opaque glass of Late Bronze Age date. The technique is uniquely capable of identifying compositional heterogeneity at a sub-micron resolution within the crystalline opacifiers dispersed through homogeneous glass matrices. It is shown that this provides crucial information on the possible raw ingredients of the opacifying inclusions used, and has the potential for highlighting regional variations in the production technology involved in creating different colours of opaque glass.  相似文献   
134.
This paper uses remote sensing data to document a raised field, chinampa system adjacent to the Postclassic kingdom of Xaltocan in the northern Basin of Mexico. Various forms of landscape information; historic records and maps as well as remote sensing; are considered to understand the chinampa system. The remote sensing data examined include 1950s aerial photographs, Landsat 7 data, and Quickbird VHR, multi-spectral imagery. This article evaluates the utility of each of these forms of data to identify buried chinampa features and integrates them in a GIS to produce a map of Xaltocan's chinampa landscape. Canals of various sizes and hydrological positions comprised the chinampas and integrated the system together. Occupying at least 1500–2000 ha, Xaltocan's chinampa system represents the largest pre-Aztec, chinampa system in the Basin of Mexico.  相似文献   
135.
We conducted experiments to compare the micromorphological signatures of modern burnt sedge and grass bedding to laminated layers of carbonized material and phytoliths in Middle Stone Age deposits at the shelter, Sibudu. The experiments were designed to clarify the formation processes associated with the laminated layers and to investigate whether these previously identified layers of bedding were deliberately burned or not. The results indicate that the laminated layers were most likely produced by human activity related to the construction, maintenance and burning of bedding. Furthermore, our experiments demonstrate that large volumes of vegetal material could have produced the relatively thin, archaeological deposits of burnt bedding.  相似文献   
136.
Queer youths and queer youth-related issues are under-researched in geography. I contribute to the existing literature by investigating how adultist practices can both constrain and empower queer youth within the context of schools. Issues involving adolescence and sexuality are complex, and these nuances become more pronounced with regard to nonnormative sexual identities and expressions. Using interviews with adult queer youth advocates in Toledo, Ohio, I look at the ways in which adults construct uncertain, anxious and contradictory ‘safe spaces’ that can work to constrain/restrict queer youth but also to empower and/or facilitate queer youths' negotiation and navigation of other, predominantly heterosexist social spaces.  相似文献   
137.
ABSTRACT The twenty‐first century will be one of intensified urbanization, on a scale never before experienced. How do urban systems and individual cities change and develop? The social sciences have many different approaches to analyzing the economic, social, and spatial dimensions of urban change. We inventory some of these approaches and their implications for public policy toward cities, urban change, and economic development.  相似文献   
138.
This chapter addresses the essential issues in evaluating works that use linguistic evidence in reconstructing the past. Linguistics has its own well-developed body of theory and practice. Its evidence is subject to rigorous validation. Any work claiming to infer history from linguistics must validate its evidence against a systematic phonological reconstruction, and it must provide that validating apparatus or else direct the reader to where that apparatus is to be found. Scholars do not get to pick and choose among the archaeological data to support their ideas. Neither does one get to pick and choose or to engage in special pleading to make the linguistic evidence fit one’s prior notions. The chapter illustrates the requirements of linguistic reconstruction by laying out the system of the Eastern Cushitic language group and showing how to apply the system, step by step, to reconstruct the presence of a particular component of the proto-Eastern Cushitic economy.  相似文献   
139.
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   
140.
The initial Late Paleolithic, said to appear between 40 and 30 kya in eastern Asia, is defined by the appearance of many innovations. These archaeological indicators include the appearance of more refined stone tool making techniques (e.g., include the appearance of blade and microblade technology), complex hearth construction, use of pigments and personal ornamentation, as well as worked faunal implements such as bone and antler tools. We report here new findings from a multidisciplinary research project conducted at the Shuidonggou (Choei-tong-keou) site complex in northern China, a series of localities that date from the initial Late Paleolithic to the Neolithic.  相似文献   
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