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71.
ABSTRACT

In the 1970s, the Zangger Committee and the Nuclear Suppliers’ Group published guidelines on nuclear trade that drew a line between peaceful and dangerous nuclear technology, defining what was sensitive enough to require safeguarding and what was not. Given the ambivalence of nuclear technology, how was that line drawn? Historically, the understanding of whether a nuclear item is benign, sensitive, or especially sensitive has changed in response to the shifting balance between political, commercial and non-proliferation interests. The 1970s, however, merit special attention; they saw an unprecedented codification of nuclear sensitivity in the form of the published trigger lists that are still used today. In the absence of clear technical criteria, what interests and perceptions determined the sensitivity of specific nuclear items by the nuclear suppliers in the 1970s? Archival sources provide a unique insight into how the trigger lists and guidelines were negotiated and with what aims and considerations. This paper finds that nuclear sensitivity was driven by commercial interests in ensuring a level, and open commercial playing field, political interests in securing co-operation and practical interests in implementation and reputation, all of which outweighed technical considerations of how nuclear technology exports might assist a nuclear weapons programme.  相似文献   
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Research at Crystal River and Roberts Island Shell Mound Complex, on the western coast of Florida, USA, offers a quantitative assessment of the temporality of shell deposit construction, Native subsistence practices, and mobility patterns through stable oxygen isotope data from eastern oyster (C. virginica). The δ18Owater values of oysters vary synchronously with salinity, assuming relatively constant δ18Owater/salinity gradients since the time of occupation, allowing for an examination of shifts in oyster habitat exploitation over time. Our previous (Thompson et al. 2015) study indicated that midden accumulation occurred throughout the year, while oysters from mound deposits were collected in colder months. New data indicate that in addition to differential season of collection, habitat exploitation also varied. During early occupation at the site, oysters were collected primarily from lower saline habitats, while in later phases oysters were obtained from higher salinity waters; we relate this to a lower sea level and concomitant settlement shift seaward. Additionally, oyster from later mound contexts was collected from higher saline habitats relative to those in midden contexts; Native people may have targeted specific bioherms at certain times for the year for feasting-related mound construction.  相似文献   
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ABSTRACT

The American Southeast saw the development of large ceremonial village centers, the coalescence of households, and monumental architecture integrated into village layout during the Middle Woodland period (ca. AD 1–600). These shifts toward more sedentary lifeways occurred independently of, and prior to, the domestication of plants across the Southeast. This paper examines the seasonality of monumental construction at the Garden Patch site located on the central Gulf Coast of Florida. This site contains evidence for rapid mound construction that followed a predetermined site plan. Here, we present oxygen isotope analyses of archaeological mollusk shells (Crassostrea virginica) to evaluate the seasonality and periodicity of monument construction. We conclude that mound construction occurred during the cooler months of the year. Ultimately, this contributes to an anthropological understanding of the development of these early ceremonial centers in the Southeast.  相似文献   
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Abstract

Two new, subcomplete forewings belonging to the ‘triassolestid assemblage’, a group of Triassic stem-relatives of dragon- and damselflies (Odonata), are described. One, recovered from Australia (Aranbanga Volcanic Group), belongs to Mesophlebia antinodalis Tillyard, 1916, previously documented on the basis of two very incomplete wings. The other, recovered from South Africa (Molteno Formation), is assigned to a new species, Mesophlebia elegans sp. nov. The new data allow a reconsideration of the diagnosis of the genus Mesophlebia Tillyard, 1916 and a re-instatement of the family Mesophlebiidae Tillyard, 1916. Notably, the new specimens possess, near the wing base, a posterior lobe absent in most ‘triassolestid’ genera, but present in crown-Odonata and a number of their stem-relatives. Lobodonata tax. nov. is erected to accommodate odonates possessing this lobe. The nature of the ‘vein-like’ element anteriorly delimiting this lobe is discussed. We submit that it might have been initially composed of an invagination of the posterior wing-margin (‘fibula’), which was later captured by AA, imposing its course on CuP.

Ayla Tierney [], Queensland Museum, PO Box 3300, South Brisbane BC, Queensland 4101, Australia; Isabelle Deregnaucourt [], Sorbonne Université, MNHN, CNRS, Centre de recherche sur la paléontologie – Paris (CR2P), 57 rue Cuvier, CP38, F-75005 Paris, France; John M. Anderson [], Evolutionary Studies Institute, Witwatersrand University, 1 Jan Smuts Ave., Braamfontein, Johannesburg 2000, South Africa; Paul Tierney [], Queensland Museum, PO Box 3300, South Brisbane BC, Queensland 4101, Australia; Torsten Wappler [], Hessisches Landesmuseum Darmstadt, Friedensplatz 1, 64283 Darmstadt, Germany; Olivier Béthoux [], Sorbonne Université, MNHN, CNRS, Centre de recherche sur la paléontologie – Paris (CR2P), 57 rue Cuvier, CP38, F-75005 Paris, France.  相似文献   
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