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991.
992.
Researchers have debated the existence of regional variation in Clovis points for over 60 years. Here, we report an attempt to resolve this argument using a large sample of Clovis points from dated assemblages and a suite of shape analysis methods known as geometric morphometrics. The study tested the two main hypotheses that have been put forward in the debate: the continent-wide adaptation hypothesis, which holds that Clovis points do not vary regionally, and the regional environmental adaptation hypothesis, which holds that there is regional variation as a consequence of Clovis groups adjusting their food-getting toolkits to local conditions. We used discriminant function analysis and a multivariate extension of the t test to assess whether differences in shape exist at two scales. The first set of analyses compared points from the most obvious environmental regions in North America, the East and the West. The second set of analyses investigated differences among points from subregions within the East and West. The analyses revealed significant differences between points from the East and the West and among points from some subregions. Follow-up analyses demonstrated that these differences are not the result of the most common confounding factors, raw material quality and resharpening. As such, the analyses support the regional environmental adaptation hypothesis rather than the continent-wide adaptation hypothesis. We conclude from this that Clovis people modified their points to suit the characteristics of local prey and/or the habitats in which they hunted.  相似文献   
993.
This article offers a historical analysis of the relationship between the practice of participant-observation among American sociologists and Erving Goffman's dramaturgical model of the self. He was a social scientist who privileged ethnography in the field over the laboratory experiment, the survey questionnaire, or the mental test. His goal was a natural history of communication among humans. Rather than rely upon standardizing technologies for measurement, Goffman tried to obtain accurate recordings of human behavior through secretive observations. During the 1950s, he conducted three major studies as a participant-observer, disguised from those studied through insincere performances. As originally presented, his dramaturgical theory did not draw upon the theater as the governing metaphor, but rather the confidence game. It is suggested that Goffman's writings exemplify what Gerd Gigerenzer calls the tools-to-theories heuristic. Goffman's depiction of the confidence man's behavior closely mirrored how he and his fellow sociologists described the practice of participant-observation. Both were represented as embedded and attentive yet coolly detached observers skilled at playing different roles as the situation necessitated. The similarities between his own professional behavior and the activities of the confidence man may have suggested to Goffman the latter as a model for human nature.  相似文献   
994.
ABSTRACT Theoretical models of urban development come to contradictory conclusions regarding the nature of central city–suburb interdependence. Unfortunately, empirical research into this relationship has been hampered by the lack of identifying information due to the endogeneity of factors affecting both central city and suburban growth. This paper resolves the identification problem by constructing an index that measures price shocks to export industries located in either center cities or their suburbs. The results indicate that positive export industry price shocks to one area have a positive spillover effect on the other. Interestingly, the cross‐elasticity of suburban employment with respect to center city employment (1.18) significantly exceeds the cross‐elasticity of central city employment with respect to suburban employment (0.24).  相似文献   
995.
Recent research in the Quijos and Cosanga valleys of the eastern piedmont of Ecuador’s Cordillera Real has revealed and substantiated previous knowledge of obsidian sources that are unrelated to obsidian flow systems in the Sierra de Guamaní, Ecuador. Neutron Activation Analysis (NAA) and X-ray Fluorescence (XRF) were carried out on 47 obsidian source samples collected from several contexts in and adjacent to the study area. From samples within the study area three distinct obsidians were characterized: Cosanga A, Cosanga B, and Bermejo. These obsidians originate from a number of obsidian-bearing rhyolitic domes recently identified in the hills west of the Río Cosanga. Extensive survey of these dome localities has identified obsidian cobbles large enough for formal and informal tool manufacture. Beyond the study area, samples were collected and analyzed from the El Tablón source in the Sierra de Guamaní, providing much needed data on this poorly understood source. In addition, a sample from the newly identified Conda Dome source, near the Cotopaxi volcano, was characterized with XRF. All samples were then compared to 57 pre-existing samples from the Mullumica–Callejones, Yanaurco–Quiscatola and Carboncillo sources in the Ecuadoran Cordillera Real, as well as to artifacts from the Sumaco area in the Ecuadorian Amazon. Results of the elemental characterization indicate that the Cosanga Valley, El Tablón and Conda Dome obsidians are chemically distinct. Further, visual characteristics of Cosanga Valley obsidian types are useful in source attribution for the large artifact samples from the region. Finally, obsidian collected from the El Tablón flow suggests that this source may have produced obsidian suitable for tool manufacture.  相似文献   
996.
997.
I review several bodies of empirical urban theory relevant to the archaeological analysis of ancient cities. Empirical theory is a type of “middle-range theory” (following Robert Merton): sets of concepts and methods that are less abstract, and have greater empirical content, than high-level social theory. The categories of theory reviewed here include environment-behavior theory, architectural communication theory, space syntax, urban morphology, reception theory, generative planning theory, normative theory, and city size theory. Most of these approaches originated in the fields of architecture, planning, and geography, and they directly link the urban-built environment to the actions of people within cities.  相似文献   
998.
Kant's ideas about, questions, and challenges to the Western tradition of philosophy reverberate into the third century of the reception of his texts. The writings of Maurice Merleau-Ponty, the twentieth-century French existential and hermeneutic phenomenologist, are interlaced with engagements with Kant's ideas. Often these incidents are marked by Merleau-Ponty's critique, yet there is a noticeable recurrence of his efforts to contend with Kant's philosophy. In Merleau-Ponty's course notes, Nature (2002), he wrestles with Kant's version of nature in the Critique of Judgment (1790), specifically citing “the happy accident” between sensibility and the understanding. This opens upon realms of metaphysical thought that remain deeply contentious within Kantian scholarship. An interrogation of this “happy accident” leads to insights about Merleau-Ponty's conceptualization of an existentialized metaphysics the implications of which shed light on theology and the judgment of God.  相似文献   
999.
The focus of this article is on precompetitive research and development (R&D) cooperation across Europe, as captured by R&D joint ventures funded by the European Commission in the time period 1998–2002, within the Fifth Framework Programme. The cooperations in this program give rise to a bipartite network with 72,745 network edges between 25,839 actors (representing organizations that include firms, universities, research organizations, and public agencies) and 9,490 R&D projects. Participating actors are linked only through joint projects. In this article, we describe a community‐identification problem based on the concept of modularity, use the recently introduced label‐propagation algorithm to identify communities in the network and differentiate the identified communities by developing community‐specific profiles with social network analysis and geographic visualization techniques. We expect the results to enrich our picture of the European Research Area (ERA) by providing new insights into the global and local structures of R&D cooperation across Europe. Este artículo se centra en la cooperación en investigación precompetitiva y desarrollo (I + D) en toda Europa tal y como se manifiesta en iniciativas conjuntas de I + D financiadas por la Comisión Europea durante el periodo 1998–2002, dentro del Quinto Programa Marco (5PM). La cooperación en este programa dio lugar a una red bipartita con 72.745 conexiones entre los 25.839 agentes (representando organizaciones que incluyen empresas, universidades, organizaciones de investigación y organismos públicos), y 9.490 proyectos de I + D. Los agentes participantes están vinculados sólo a través de proyectos conjuntos. En este artículo describimos un problema de identificación comunitaria basado en el concepto de modularidad, usamos el recientemente introducido algoritmo de propagación de etiquetas, Label‐propagation Algorithm (LPA) para identificar las comunidades en la red, y diferenciamos las comunidades identificadas desarrollando perfiles específicos comunitarios mediante el análisis de redes sociales y técnicas de visualización geográfica. Esperamos que los resultados enriquezcan nuestra visión del Espacio Europeo de Investigación (European Research Area, ERA), aportando nuevas perspectivas sobre las estructuras globales y locales de cooperación en I + D en Europa. 本文关注1998–2002年间在第五框架计划(FP5)下由研究与发展联合基金支持的欧盟研发计划中的竞争前欧洲研发合作。该项目合作形成一个在25839个参与者(执行组织,包括企业,大学,研究机构级公共部门)和9490个项目间拥有72745条边的双向网络,参与者仅仅通过合作项目连接。本文描述了基于模块化的社团识别问题。利用最近发展的标签传递算法(LPA)对网络群体进行识别,利用社会网络分析和地理可视化方法构建了群体专属的描述,区分识别出不同研发群体的资料。希望上述结果可以提供欧洲范围内研发合作的全局和局部结构的新视角,从而丰富欧洲研究区(ERA)的图景。  相似文献   
1000.
Charcoal forms a crucial source of archaeological and palaeoenvironmental data, providing a record of cultural activities, past climatic conditions and a means of chronological control via radiocarbon (14C) dating. Key to this is the perceived resistance of charcoal to post-depositional alteration, however recent research has highlighted the possibility for alteration and degradation of charcoal in the environment. An important aspect of such diagenesis is the potential for addition of exogenous “humic acids’ (HAs), to affect the accuracy of archaeological and palaeoenvironmental reconstructions based upon chemical analyses of HA-containing charcoal. However the release of significant quantities of HA from apparently pristine charcoals raises the question whether some HA could be derived via diagenetic alteration of charcoal itself. Here we address this question through comparison of freshly produced charcoal with samples from archaeological and geological sites exposed to environmental conditions for millennia using elemental (C/H/O) and isotopic (δ13C) measurements, Fourier Transform Infrared Spectroscopy (FTIR) and proton Liquid-State Nuclear Magnetic Resonance (1H NMR). The results of analyses show that the presence of highly carboxylated and aromatic alkali-extractable HA in charcoal from depositional environments can often be attributable to the effects of post-depositional processes, and that these substances can represent the products of post-depositional diagenetic alteration in charcoal.  相似文献   
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