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341.
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We develop a new approach to the study of representation based on agenda setting and attention allocation. We ask the fundamental question: do the policy priorities of the public and of the government correspond across time? To assess the policy priorities of the mass public, we have coded the Most Important Problem data from Gallup polls across the postwar period into the policy content categories developed by the Policy Agendas Project ( Baumgartner & Jones, 2002 ). Congressional priorities were assessed by the proportion of total hearings in a given year focusing on those same policy categories, also from the Agendas Project. We then conducted similar analyses on public laws and most important laws, similarly coded. Finally we analyzed the spatial structure of public and congressional agendas using the Shepard‐Kruskal non‐metric multidimensional scaling algorithm. Findings may be summarized as follows: First, there is an impressive congruence between the priorities of the public and the priorities of Congress across time. Second, there is substantial evidence of congruence between the priorities of the public and lawmaking in the national government, but the correspondence is attenuated in comparison to agendas. Third, although the priorities of the public and Congress are structurally similar, the location of issues within the structure differs between Congress and the general public. The public “lumps” its evaluation of the nations most important problems into a small number of categories. Congress “splits” issues out, handling multiple issues simultaneously. Finally, the public tends to focus on a very constrained set of issues, but Congress juggles many more issues. The article has strong implications for the study of positional representation as well, because for traditional representation to occur, there must be correspondence between the issue‐priorities of the public and the government. We find substantial evidence for such attention congruence here.  相似文献   
343.
Scientific disputes on the objectivity of research results are an integral part of the collective production of knowledge. One motivation to study cases of scientific controversy is the attempt to discover general patterns in the behaviour of participants and institutions involved in such controversies. Yet, for there to be a controversy, one must assume an important amount of social interaction, so much so that it renders it an essentially social phenomenon, which is accessible to historical study. Cases of obvious scientific fraud, in addition, are neither clear‐cut nor rare and the mere accusation of scientists by their peers frequently constitutes considerable examples of scientific debate. Together with this, it is often assumed that publication organs play a dominant role in directing the lines of scientific controversy, but their institutional significance and the task of individual editors remain widely unexplored. The present article studies the prominent Nature affair of the Parisian biomedical scientist Jacques Benveniste, both, from a perspective on scientific fraud and on the beginning and closure of scientific disputes. One of the most remarkable features of Benveniste's antibody dilution experiments was that they stroke at the foundations of modern physical and biomedical sciences. Could recent history of science actually resolve the case of the so‐called ‘memory of water’ phenomenon?  相似文献   
344.
The study of location and colocation of economic activities lies at the heart of economic geography and related disciplines, but the indices used to quantify these patterns are often defined ad hoc and lack a clear statistical foundation. We propose a statistical framework to quantify location and colocation associations of economic activities using information-theoretic measures. We relate the resulting measures to existing measures of revealed comparative advantage, localization, specialization, and coagglomeration and show how different measures derive from the same general framework. To support the use of these measures in hypothesis testing and statistical inference, we develop a Bayesian estimation approach to provide measures of uncertainty and statistical significance of the estimated quantities. We illustrate this framework in an application to an analysis of location and colocation patterns of occupations in US cities.  相似文献   
345.
Systems thinking is regarded as a key competence in the field of education for sustainable development (ESD), because it helps students to understand the complexity and dynamics of natural, social and economic systems. In our research group, we developed a competence model that distinguishes four dimensions of systems thinking in ESD. Based on this model, we designed different university courses in biology and geography teacher education and measured their effects on student teachers’ systems thinking and the pedagogical content knowledge for teaching systems thinking with two different tests. Both variables could be effectively promoted depending on the course.  相似文献   
346.
This report explores a hypothesis that the Norman's Bay shipwreck is the Wapen van Utrecht, a 64‐gun Dutch ship lost during the Battle of Beachy Head in 1690. The shipwreck, found off the Sussex coast, was designated by the Protection of Wrecks Act (1973) in 2006, when it was speculated that the wreck was the English 70‐gun ship Resolution, lost in the Great Storm of 1703. Dendrochronology dates the vessel after the middle of the 17th century AD, however, with timbers from Germany or the Low Countries. Initiatives by the Nautical Archaeology Society to bring the protected wreck to a wide public are also discussed.  相似文献   
347.
American-produced B-29 Superfortress bomber aircraft flew missions against Imperial Japan in the Pacific Theater from air bases in the Mariana Islands from November 1944 until the end of WWII. Mechanical failures forced many B-29s into the ocean surrounding Saipan and Tinian. Terrestrial wreckage of these aircraft has been located in the Pacific region, but no losses in deep water were located until 2016, when a NOAA exploration cruise investigated sonar targets in the Saipan Channel, between Saipan and Tinian. Disarticulated wreckage from a B-29 was located at 370 m over a large area of the seabed. Telepresence-enabled, non-invasive exploration from NOAA Ship Okeanos Explorer allowed scientists on shore to view live streaming video and to work collaboratively to guide the investigation. Experts in aviation archaeology, corrosion studies, WWII history, forensic studies, marine biology, and oceanography participated in the survey using an ROV, highlighting components which could lead to possible identification of the B-29 in situ, and conducting an environmental characterization of the site. This deep-water aircraft site exemplifies multiple-stakeholder driven research in aviation archaeology and highlights several issues in the value of individual site identification.  相似文献   
348.
Australia in 2006 reaffirmed its close relationship with the United States while deepening engagement with other major power partners, with further agreements concluded with China, cooperation extended with Japan, and the profile of ties with India enhanced. Australia continued to navigate through the sometimes sensitive relations among the major powers, amid additional pressures arising from North Korea's nuclear test. Tensions with Indonesia were followed by a new security agreement, though increased confidence was needed in the relationship at both official and public levels. Internal disorder in several southwest Pacific states challenged Australia's capacities to provide effective short and medium term responses. Involvements in Afghanistan and Iraq continued, with the latter situation particularly problematic. Growing demand for energy in the Asia–Pacific region directed further attention towards Australia's uranium resources, as climate change issues assumed a higher profile in domestic debate and multilateral activities.  相似文献   
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350.
Different post-IR Infrared Stimulated Luminescence (IRSL) approaches are applied to sediments from a Holocene coastal foredune sequence on Ruhnu Island in the eastern Baltic Sea. The comparison of D e-values and ages determined by the different approaches is complimented by fading and bleaching experiments. The fading experiments imply strong fading of IRSL (50°C) signals and no fading of any of the post-IR IRSL signals, but this is not confirmed by the determined D e-values. In fact, post-IR IRSL (150°C) D e-values agree within errors with those calculated for IRSL (50°C). From the bleaching experiments it is inferred that the higher values observed for post-IR IRSL at more elevated stimulation temperatures (225°C/290°C) are likely related to either thermal transfer and/or slow-to-bleach components within the signal. For the dating of the Holocene foredune sequence of Ruhnu Island, the post-IR IRSL (150°C) approach is preferred and these agree with the limited independent age control available from radiocarbon dating. Accordingly, the sequence formed between ca. 7.0 ka and 2.5 ka ago.  相似文献   
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