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71.
This study explores how a scientist's location in science‐based policy networks can affect her policy‐oriented behaviors. In particular, we hypothesize that those scientists who fill structural holes in their networks will be more likely than others to engage in policy‐oriented behaviors. The network data are defined by scientists' coauthorship on policy documents regarding climate change in the Great Lakes. We employ a two‐mode network analysis to identify clusters of scientists who coauthored similar documents, and relative to those clusters, we identify those who fill structural holes by bridging between clusters. We find that those scientists who bridged between clusters were more likely to engage in policy‐oriented behaviors of policy advocacy and advising than were others in the network. This is an example of a link between network location and policy‐oriented behavior indicative of the broader phenomenon of how individuals exert agency, given structural constraints.  相似文献   
72.
This paper summarises the current development in the southern Ionian Islands (Kefallinia and Zakynthos) prehistory and places it within the context of seafaring. Archaeological data from the southern Ionian Islands show human habitation since Middle Palaeolithic going back to 110 ka BP yet bathymetry, sea-level changes and the Late Quaternary geology, show that Kefallinia and Zakynthos were insular at that time. Hence, human presence in these islands indicates inter island-mainland seafaring. Seafaring most likely started some time between 110 and 35 ka BP and the seafarers were the Neanderthals. Seafaring was encouraged by the coastal configuration, which offered the right conditions for developing seafaring skills according to the “voyaging nurseries” and “autocatalysis” concepts.  相似文献   
73.
The loess site at Boynychi (the Volyn Upland) is of essential importance for the stratigraphy of Middle and Upper Pleistocene in Central Europe. The profile was recently dated by Fedorowicz and Prylypko in 2007 (parallel dating), and by Kusiak in 2009. The Upper Vistulian loesses are much thicker in the exposure from 2009 than in the earlier examined one (2007). The list of results obtained in the Gdańsk, Kiev and Lublin laboratories, respectively, can be divided in two. The first group contains the results obtained for the Horohiv and Korshiv pedocomplexes and for the loess from the penultimate glacial, which separates these pedocomplexes. The results from all laboratories are very similar and rather well describe the real age of dated deposits. The second group contains the widely differing results of dating of the Vistulian loesses. The TL ages obtained by Fedorowicz and Prylypko are considerably older than those obtained by Kusiak in the new exposure. The latter ones excellently correspond to the geologic-stratigraphic interpretation of the profile. Two incompatible series of TL dating results indicate that local variability of loess accumulation conditions in different stages of their formation may have resulted in incomplete luminescence zeroing of mineral material before deposition.  相似文献   
74.
An integrated analysis of recent satellite imageries and dated aerial photos demonstrated to be a good investigation tool (Gallo et al., 2009) for the identification of new sites and for the assessment of landscape changes of wide archaeological areas in Ethiopia.  相似文献   
75.
In this paper, we explore regional innovation in the use of varieties of algae as inputs to industrial processes. It is important to understand that algae are one of nature's most bountiful products, with an almost infinite variety of applications. Algae have received prominence in the research literature because of the strong evidence that they can make a major contribution to the production and—importantly—storage of renewable energy. Following the introduction to this paper, Section 2 reviews the nature and application of algae in two main aspects of clean energy production: first as biogasolene or biodiesel; second as large-scale storage batteries for electricity. The latter is particularly important as one classic deficiency of electricity is the difficulty in storing it for lengthy periods other than in short-life batteries. However (Section 3), there are other uses for algae, ranging from aquaculture to medicine and the production of cosmetics. In the southwest corner of the Iberian Peninsula, between Faro in Portugal through Huelva to Cadiz in Spain, is a significant research and commercial algae production zone. The paper describes the key system elements in play in this trans-border innovation network and considers prospects for new path creation towards biofuels, the main research and application centres for which are in the San Francisco Bay Area in California. Conclusions and recommendations for policy action are then drawn.  相似文献   
76.
Herbivores, as taphonomic agents, can modify and consume bones and antlers for no nutritive purpose. This unusual behavior is due to a nutritional dysfunction (osteophagia) that allows them to supplement a lack of minerals in their diet through ingestion of minerals contained in bones. When chewing, herbivores change skeletal element morphology and produce a characteristic forked shape. At an incipient stage of modification, herbivore chewing may mimic that of carnivores. In this paper, we provide diagnostic criteria to distinguish bone modification made by herbivores from that produced by other taphonomic agents, mainly carnivores.  相似文献   
77.
The history of the interlaboratory comparison of TL dating results in Poland started in the 1980s. At that time the Lublin, Warsaw and Silesian laboratories made the first attempts at TL dating of the same loess samples from the Odonów profile. However, the cooperation ceased for many years due to great differences in the obtained TL age estimates. The next interlaboratory comparisons were made in the years 2000–2009 for the loess samples from several Polish (Dybawka, Tarnawce, Dankowice, Biały Kościół) and Ukrainian (Boyanychi, Halych, Velykyj Hlybochok, Yezupil) profiles. Most of the compared dates, obtained for the loess deposits from the Upper Pleistocene and younger part of the Middle Pleistocene, were consistent. This encouraged us to undertake the Gdańsk-Lublin interlaboratory cooperation in dating of 200-700 ka old loess deposits. Nine samples were taken from the Ukrainian profile Mamalyha 2 in 2009 for this purpose. The TL dating results indicate that comparable dates are obtained in two laboratories for loess deposits younger than 300 ka BP. The TL signal obtained in the Gdańsk laboratory for the samples older than 300 ka BP was saturated so such samples should not be dated by the multi-aliquot regeneration method. The results obtained in the Lublin laboratory for these deposits (489–682 ka) confirm that it is possible to date loess deposits older than 500 ka. It probably results from the use of total-bleach method with preheating at 160°C for the equivalent dose determination.  相似文献   
78.
Archaeobotanical remains of ground cereals from prehistoric northern Greece are discussed in this paper within the context of ethnographic and textual evidence for similar food preparations encountered in countries of the Mediterranean and the Middle East. The archaeobotanical remains consist of ground einkorn and barley grain, stored in this form, from the sites of Mesimeriani Toumba and Archondiko respectively, located in the region of central Macedonia, northern Greece. The results of published pilot studies involving macroscopic, experimental, and scanning electron microscopic examination of these archaeological finds seem to suggest that these products correspond to preprocessed cereals, stored in this form. It is also likely that some at least of these finds were produced from boiled and subsequently ground cereal grains. This practice identified in the prehistoric material is similar to various forms of processing cereals still widely encountered in rural areas of modern Greece and other circum-Mediterranean countries. These products are known in Greece under the names of pligouri (bulgur) and trachanas. Through a combined examination of archaeobotanical, ethnographic, and textual evidence it is argued that the idea of pre-processing cereals for piecemeal consumption throughout the year is of considerable antiquity in this part of the world. Drawing information from food science research on similar, modern traditional preparations of the same geographical region, the paper highlights the advantages of pre-processing cereals for later consumption, which offers insights into likely prehistoric subsistence practices. Parboiling cereal grains or mixing grains with milk products in the summer would have made excellent use of seasonally available ingredients by converting them into nutritious and storable foodstuffs, which could then be consumed as part of daily meals with very little additional cooking effort and fuel. This ease of conversion into a filling meal may justify us considering them as ‘traditional fast foods’.  相似文献   
79.
Abstract

This paper is concerned with the relationship between literature and the construction of place-myth relating to the story Mutiny on the Bounty. In 1790, nine British mutineers together with their Tahitian companions settled on Pitcairn Island where they remained hidden for nearly 20 years. The story of the mutiny is not myth but has served to mythologize Pitcairn through the various tropes of literature written about the Bounty saga. As literary place Pitcairn represented the image of a ‘utopian paradise’. This discussion, through qualitative literary analysis and the process of textualization, evokes the idea of mapping, naming, and imagining islands. It identifies how the utopia/paradise place-myth of Pitcairn has persisted through time and become ultimately inseparable from its textual topography. But conversely, discussion exposes the paradoxical problem between myth and reality of islands and their representations. It highlights complex internal and external boundaries of identification that arise in the host visitor experience. Literary place-myth is rendered as powerful, persistent, mutable, and historically-rooted.  相似文献   
80.
Controversy has erupted in Selma, Alabama, over recent efforts to commemorate the career of Nathan Bedford Forrest, a Confederate cavalry officer and founding member of the original Ku Klux Klan. More generally, the controversy in Selma is emblematic of an enduring regional pattern in which contests over the future are couched in terms of the past. Relative to other media, monuments appear to be trustworthy and lasting. Despite this appearance of historical consensus and stability, the city's public spaces are the product of and conduit for ongoing politics. The current conflict pits memorial activists associated with the Civil Rights Movement against neo‐Confederates. Interpreted in the context of Selma's increasing promotion of Civil Rights heritage and the recent election of the city's first African American mayor, the Forrest affair highlights the utility of the concept of symbolic accretion for understanding the complexities of commemorating antagonistic histories in the same place. Symbolic accretion describes the appending of commemorative elements onto already existing memorials. The situation in Selma suggests two different types of symbolic accretion, allied and antithetical. More generally, the act of commemoration itself may be understood as a process of accretion in that heretofore anonymous spaces are formally recognized via the grafting of memorial elements.  相似文献   
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