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81.
This paper considers the “share‐altering” technical change hypothesis in a spatial general equilibrium model where individuals have different levels of skills. Building on a simple Cobb‐Douglas production function, our model shows that the implementation of skill‐biased technologies requires a sufficient proportion of highly educated individuals. Moreover, when technical progress disproportionately replaces middle‐skill jobs, the local distribution of skills will exhibit “fat‐tails,” where the proportion of both highly skilled and low‐skilled workers increases. These and several other predictions of the model are consistent with recent existing evidence, and avoid some major criticism against the “canonical” CES framework.  相似文献   
82.
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing.  相似文献   
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84.
Summary

The issue which I wish to address in this paper is the widespread tendency in Anglophone philosophy to insist on a separation between the history of philosophy and the history of ideas or intellectual history. This separation reflects an anxiety on the part of philosophers lest the special character of philosophy will be dissolved into something else in the hands of historians. And it is borne of a fundamental tension between those who think of philosophy's past as a source of ideas and arguments of interest to the present, and those who hold that the philosophy of the past should be studied on its own terms, in relation to its immediate context, without reference to the present. The challenge, then, is to re-historicise the history of philosophy, and to keep the philosophers onside.  相似文献   
85.
This article presents a method to identify “Absolute and Relative Employment Concentration (AREC) areas” for a particular industry. Two novel characteristics of the method are that it simultaneously analyses AREC, and that it combines spatial concentration per area with the spatial concentration in neighbouring areas. The method is easy to understand and apply. It is developed to assist regional policy makers and corporate decision-makers with their investment decisions related to new infrastructure or plants. The identification of concentration areas also allows for analysing the performance of these areas in relation to characteristics such as infrastructure availability and the housing and labour market. This can yield new academic insights that are relevant for regional planners. An application of the newly developed method to five industries in a Dutch province subdivided into 502 areas illustrates the value of the method in comparison to other methods.  相似文献   
86.
In a talk given at Zurich in the late 1940s, Hermann Weyl discussed Ferdinand Gonseth's dialectical epistemology and considered it as being restricted too strictly to aspects of historical change. His experiences with post-Kantian dialectical philosophy, in particular Johann Gottlieb Fichte's derivation of the concept of space and matter, had been a stronger dialectical background for his own 1918 studies in purely infinitesimal geometry and the early geometrically unified field theory of matter (extending the Mie-Hilbert program). Although now Weyl distantiated himself from the speculative features of his youthful philosophizing and in particular from his earlier enthusiasm for Fichte, he again had deep doubts as to the cultural foundations of modern mathematical sciences and its role in material culture of high modernity. For Weyl, philosophical «reflection» was a cultural necessity he now turned towards Karl Jaspers' and Martin Heidegger's existentialism to find deeper grounds, similar to his turn towards Fichte's philosophy after World War I. The discussion in the late 1940s can be read as a kind of post-World-War-II «Nachtrag» to Weyl's more widely known philosophical comments on mathematics and the natural sciences published in the middle of the 1920s.  相似文献   
87.
At the beginning of the XVIII th century, Wilhelm Gottfried Leibniz and Friedrich Hoffmann criticize Georg Ernst Stahl's medical theory. They differenciate between unsound and true reasonings. Namely, they validate Stahl's definition of breath but extracting it from its animist basis and placing it in an epistemology obeying to the principle of sufficient reason and to the mechanical model. The stahlian discovery consists in understanding breath as a calorific ventilation against the ancient conception; the iatromechanists recognize its accuracy, but they try then to transpose it to a mechanical model of ventilation. Using it in a different epistemological context implies that they analyze the idea of discovery "true" in its contents, but "wrong" in its hypothesis. It impels to examine the epistemology of medical knowledge, as science and therapeutics, and in its links with the other scientific theories. Thus, if Leibniz as philosopher and Hoffmann as doctor consider Stahl's animism so important, it is because its discoveries question the fundamental principles of medicine.  相似文献   
88.
Issue redefinition and venue shopping have been identified as key strategies for enacting agenda and policy change, but much work remains to be done in elaborating these processes. I argue that an important aspect of issue redefinition involves shifting not only the image of an issue but also the bases for considering those issues—what I call policy principles. Policy principles are the core values, beliefs, or guidelines attached to policies that help direct decision making. The emergence and acceptance of new principles by the public and policymakers can be a vital source of policy change, at times having far greater consequences for policy than redefining an issue. Venue shopping is also a multifaceted undertaking involving efforts by policy entrepreneurs and advocacy groups to keep issues out of venues they would rather not participate in as well as move decision making to new arenas. Moreover, while the literature suggests that shifting venues is usually a sensible strategy, sometimes venue shopping can backfire. A case study of the municipal movement to restrict the nonessential use of lawn and garden pesticides in Canada illustrates these theoretical points and shows the applicability of agenda setting models to contexts outside the United States.  相似文献   
89.
This paper examines historical geographies of speleology in Britain between 1935 and 1953. As the study of caves, speleology was constructed as a sporting-science. The paper traces the formation and activities of the British Speleological Association, the influence of the speleologist Eli Simpson, arguments relating to the practice of speleology, and the formation of the Cave Research Group in 1947, to examine the geographies of science that emerge through speleology. By tracing some of the spatial, social and practical issues within the histories of speleology, distinct social and regional geographies are uncovered. Debates about practising science, definitions of speleology as sporting-science and ‘the right kind of speleologist’ complicate the geographical histories of speleology within Britain. As well as emphasising the spatial outcomes of these issues, I suggest that personality can also impact upon geographies of science in profound ways.  相似文献   
90.
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