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Home range is commonly understood to be the distance from home that children are allowed to go in the outdoor environment with the term being used within various academic disciplines. Different factors influence children's home range including traffic, age, parental fears and understandings of what it means to be a good parent. Research addressing home range over different generations has identified a context of changes in the built environment, demography and technology. This paper reports results from three generations of two families in Sheffield in the north of England and confirms a reduction in four major domains: home range, variety of outdoor spaces visited, range of activities undertaken and the number of companions.  相似文献   
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This article combines the historical record of presidential-congressional relations with previous scholarly findings to develop a model that identifies the members of Congress whose support is critical to the president's ability to build enacting coalitions. It then analyzes the relationship between President Obama and the House of Representatives during the 113th Congress as a case study that demonstrates the model's utility. Conventional wisdom and political pundits suggest that presidents working in divided government will have impossible difficulty working with Congress, but history suggests otherwise. The president's ability to successfully build enacting coalitions during divided government requires him to perform two rather disparate tasks. First, the president must minimize the amount of presidential party members who cross party lines to vote against the president's position. Second, the president must entice at least some opposition party members to cross party lines and support the president's position. Using data from 1981 to 2015, I find that representatives’ behavior on presidential support votes are related to constituency-level presidential strength, electoral vulnerability, ideological moderation, and ideological extremity. I use these results to identify the critical members of the 113th Congress. When a majority of these critical members supported President Obama's positions his legislative efforts were successful. When a majority of these members opposed the president's positions, the House Republican majority defeated the president.  相似文献   
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When black Americans and white Americans want the president to do different things, who wins? When low-income earners prefer different government action than do middle and high-income earners, whose preferences are reflected in presidential behavior? Recent studies show that congressional behavior often most closely follows the preferences of the white and the wealthy, but we know relatively little about presidential behavior. Since the president and Congress make policy together, it is important to understand the extent of political equality in presidential behavior. We examine the degree to which presidents have provided equal representation to these groups over the past four decades. We compare the preferences of these groups for federal spending in various budget domains to presidents’ subsequent budget proposals in those domains from 1974 to 2010. Over this period, presidents’ proposals aligned more with the preferences of whites and high-income earners. However, Republican presidents are driving this overall pattern. Democratic presidents represent racial and income groups equally, but Republicans’ proposals are much more consistent with the spending preferences of whites and high-income earners. This pattern of representation reflects the composition of the president's party coalition and the spending preferences of groups within the party coalition.  相似文献   
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The Australian government's White Paper on aid provides a blue print for the Australian aid program for the next decade. While it ostensibly has a focus on poverty, it still sees economic growth and effective government as the path to poverty reduction. This article analyses and highlights the issues associated with this approach to poverty. These are: growing inequality and vulnerability, the rural–urban divide in poverty outcomes, and increasing social exclusion leading to increasing social and political insecurity. The article then examines the alternative policies adopted by the British aid agency, DFID, and concludes with some suggestions on how the practice of the Australian aid program can better match the goal of poverty reduction.  相似文献   
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Harvesting different species as foods or raw materials calls for differing skills depending on the species being harvested and the circumstances under which they are being taken. In some situations and for some species, the tactics used are mainly behavioral—that is, people adjust, or adapt, their own actions to fit the behavior and circumstances of the species they are taking. Under other circumstances and for other species, the skills and tactics used may call for greater environmental preparation or manipulation. Therefore, instead of trying to distinguish people today and in the past as either foragers or farmers, it makes sense to define human subsistence behavior as an interactive matrix of species and harvesting tactics, that is, as a provisions spreadsheet.  相似文献   
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ABSTRACT We investigate the relationship between income tax rate variation and internal migration for the unique case of Switzerland, whose system of determining tax rates primarily at the community level results in enough variation to permit analysis of their influence on migration. Specifically, using Swiss census data, we analyze migratory responses to tax rate variations for various groups defined by age, education, and nationality/residence permit. The results suggest that young Swiss college graduates are most sensitive to tax rate differences, but the estimated effects are not large enough to offset the revenue‐increasing effect of a rise in tax rate. The migratory responses of foreigners and other age‐education groups are even smaller, and reverse causation seems negligible.  相似文献   
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López-Gappa, J., Pérez, L.M. & Griffin, M. February 2017. First record of a fossil selenariid bryozoan in South America. Alcheringa XX, xxx-xxx. ISSN 0311-5518.

Selenariidae Busk 1854 (Bryozoa) is considered endemic to Australia and New Zealand. Here we describe a new species of Selenaria Busk 1854 from the lower Miocene Monte León Formation (Patagonia, Argentina). Selenaria lyrulata sp. nov. is characterized by autozooids with a lyrula-like, anvil-shaped cryptocystal denticle, opesiular indentations and lateral condyles, as well as avicularia with a shield of fused costae. This is the first record of a selenariid bryozoan in South America.

Juan López-Gappa [] CONICET—Museo Argentino de Ciencias Naturales. Av. Ángel Gallardo 470, C1405DJR, Ciudad Autónoma de Buenos Aires, Argentina; Leandro Martín Pérez [] and Miguel Griffin [], CONICET—División Paleozoología Invertebrados, Museo de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.  相似文献   

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