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Eastern North America in late Pleistocene times was characterized by two major environmental regions: a periglacial tundra or open spruce parkland and an extensive complex boreal/deciduous forest in the unglaciated, lower latitudes. These environments selected for different adaptive strategies on the part of human foraging groups—known archaeologically as Paleoindians. Those in the tundra and tundra-forest region were highly mobile, possibly specialized hunters, exploiting caribou; those in the forest were generalists, exploiting a variety of subsistence resources with a less mobile settlement system. There is little evidence in either area for hunting of Pleistocene megafauna. These differences in adaptive strategies are reflected in the record of sites and isolated fluted points scattered throughout the region, as well as aspects of tool technology, function, and patterns of stone use.  相似文献   
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Biogeographers, ecologists, palaeontologists, and conservation managers often deal with checklists in which not all individuals have been identified to a species level, or the accuracy of species identification is questionable. Is it possible and credible to investigate species richness based on such checklists? Studies on macrofauna in the Far Eastern seas, eastern Arctic seas, and adjacent waters of the Pacific and Arctic Oceans suggest that in different habitats and for diverse taxa, species, and higher taxa richness strongly correlate with each other and increase with an expansion in the study area and sample size according to the species–area law. Such an increase is higher in the bottom zone than in the pelagic. Species and higher taxa richness also show a decrease from lower to higher latitudes, which is in line with the Humboldt–Wallace’s law. According to Willis’ law and self-similarity in the organisation of taxonomic levels, species richness can be assessed based on the genus, family, and order richness. In other words, supraspecies richness itself can tell us the same as species richness and therefore certain global patterns revealed at the species level may also be revealed at the supraspecies level. Such a concordance in general trends among richness parameters at different taxonomic levels in practice implies that species richness can be studied based on lists that lack species identifications or lists with doubtful species identification. We suggest bolder use of supraspecies richness in science and practice, discussing the disadvantages and advantages of this approach.  相似文献   
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Community renewable energy (CRE) represents a growing empirical and academic turn towards community‐based sustainability and climate change interventions. This paper brings together postcolonial theory and CRE for the first time to outline fundamental tensions in the conceptualisation and application of the idea of community. The understanding of community within the CRE discourse is largely: (1) location‐based; and/or (2) a community of choice that is consciously opted into. Driven by postcolonial theory, this paper counterpoises both as a form of community as contract against an idea of community as solidarity. Its central thesis is that actually existing community, contrary to how the bulk of CRE literature commonly understands it, is a combination of bonds of solidarity and emergent purposes. The paper conceptualises community as fluid bonds of solidarity that align and realign differently around different purposes.  相似文献   
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Climate change mitigation triggers both spatial and moral complexities, as demonstrated by the contentious issue of phasing out coal power. The success of the Paris Agreement depends on, among other things, the acceptability of climate policy measures and thus, from a moral perspective, on the ability to organize transition processes in ways that do not damage the livelihoods of workers, communities, and entire regions. Spatially, the unequal distributions of burdens and advantages of both climate change and respective mitigation measures provoke struggles over their legitimacy in contexts ranging from local to global. Phasing out coal mining and the respective power generation capacity thus triggers processes of structural transformation that cut across geographic scales, vertical levels of policy and politics, as well as sectoral boundaries.In light of the urgency of the climate crisis, countries such as Canada and Germany have established stakeholder-driven commissions to develop proposals for just transition pathways for phasing out coal production and consumption. We argue that these commissions are arenas in which spatial, moral, and sectoral (re-)negotiations materialize. Comparing the Canadian and German stakeholder commissions through expert interviews with their members, the article traces how governments use commissions to legitimize their transition policies. Expectations at different levels and from different actors in turn place commission members under pressure to justify their involvement and the outputs of the commissions. We find that the Canadian task force showed greater commitment to collecting and reflecting the needs of communities in its coal regions, and to communicating these to the federal government. In the German coal commission, legitimation strategies focused mainly on a broad representation of interests, and on government spending for affected regions, workers, and industries. In that case, a compromise was reached that satisfied most, but not all, of the diverse requirements.  相似文献   
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This article examines the intense debates over the New Criminal Code of Great Qing (Da-Qing xin xinglü) in the National Assembly (Zizheng yuan) during the Qing empire’s New Policy Reform (1901–11). The focus is on the conflict between those who drafted and supported the new code and those who expressed reservations, especially over reform of the laws on filial piety and fornication. The issue of reconfiguring the family and social order through law was closely related to the overarching agenda of twentieth century legal reform in China—making an empire that “ruled through the principle of filial piety” into a modern nation-state that had direct relationships with its citizens. More importantly, an analysis of the late Qing debate over family law enables this article to problematize such concepts as “Chinese” and “Western” during this crucial moment of China’s empire-to-nation transformation. It showcases the paradox of China’s modern-era reforms—a contradiction between imposing Western-inspired order with a largely indigenous logic and maintaining existing sociopolitical order in the name of preserving national identity.  相似文献   
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Geographical distance constitutes friction in searching for research collaborators. Taking advantage of a quasinatural experiment featured by High-Speed Railway (HSR) lines in China, this paper employs the difference-in-differences model to identify the causal impact of a substantial improvement in the intercity transportation infrastructure on collaborative innovation across cities. The data pertain to a universe of patent applications filed by Chinese universities and their citations. We find that HSR contributes to a substantial increase in the innovation quantity and quality of collaborative patenting innovation between universities and corporates. It contributes to industry collaboration by utilizing university academic disciplines in the related technology fields. Lastly, HSR facilitates universities to search for new research partners with better quality beyond the geographical boundary.  相似文献   
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The article explores the role of state-owned enterprises (SOEs) in the globalisation of China's infrastructure capital. Examining how accumulation strategies of Chinese SOEs are driven by a complex set of political and economic, state and private, interests, it foregrounds the inherently hybrid nature of China's state capitalism. We use Kenya's Standard Gauge Railway (SGR) as a case study to analyse how state infrastructure capital traverses borders, and the specific ways that contradictions of accumulation in China are relocated through the improvised hybridity of SOEs. In Kenya, China Road and Bridge Corporation, the main SGR contractor, shifted and adapted its strategies as the pursuit of economic productivity gave way to political priorities in China, simultaneously responding to changing socio-political circumstances in Kenya and across East Africa. Analysing these dynamics, we highlight the contingencies of, and limitations to, structural reorganisation of actually existing forms of state capitalism in China and beyond.  相似文献   
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Recent Paleolithic work along the middle Enisei River of central Siberia has revealed a long history of occupation that almost certainly begins in the Middle Pleistocene. Although the evidence for the Lower Paleolithic is somewhat tentative, there is good reason to believe that hunter-gatherers had periodically occupied the middle Enisei before the last interglacial. The steppe environment of the region during the Upper Pleistocene was relatively bountiful; more than 200 Upper Paleolithic sites, both before and after the Last Glacial Maximum, have been located. The region appears to have been abandoned during the Last Glacial Maximum. Most of Soviet and Russian archaeological work has been guided by a cultural–historical orientation, but recently there has been increased interest in developing adaptationist and ecological research strategies. The middle Enisei and the wider central Siberian region are key to understanding early adaptations to the north and the dimensions of Paleolithic population movements.  相似文献   
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