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Telepresence-enabled exploration of deep sea environments has developed over the past 30 years, providing access to archaeologists, scientists, and the general public to sites otherwise inaccessible due to depth. Pioneered through the inception of the JASON Project in the late 1980 s, telepresence missions have expanded to two dedicated ships of exploration, NOAA Ship Okeanos Explorer and exploration vessel Nautilus, and has been implemented on a series of opportunistic missions on other vessels. This paper chronicles the history of the use of telepresence for the exploration of shipwrecks in deep water as well as how this capability has allowed the public to engage with such missions. Broadening the scope of who can explore the deep sea, telepresence has also expanded what is observed and documented in the deep, which speaks to humanity’s use of the maritime world and an archaeology of discard through our material disposed of into the deep sea.  相似文献   
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The US–ROK alliance during the First Korean Nuclear Crisis provides the most likely case of high alliance cohesion. Curiously, however, instead of dancing to the American tune in their joint management of the Democratic People's Republic of Korea (DPRK) threat, the Republic of Korea (ROK) caused frequent policy collisions – supporting the US–DPRK negotiations at one point and opposing it at another – at the risk of jeopardizing its physical security. The main finding here is that the variations in the South Korean behavior were a function of their experience of status inconsistency. In particular, the ROK became compliant with the US–DPRK talks when it believed that its desired status marker of taking the leadership role in crisis management was within reach, and unyielding otherwise. These fluctuations ended up not only eroding the US–ROK alliance cohesion but also inhibiting a successful resolution of the crisis. All this bears directly on the fundamental question of whether international politics is to be understood in essentially realist terms.  相似文献   
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The aim of this work is to characterize the original concrete from Roman buildings for public spectacles, theatre and amphitheatre, from Emerita Augusta, Mérida, Spain. An advanced knowledge of the Roman concrete composition is required for a reliable restoration and preservation of these ancient monuments. The concrete was studied through mineralogical (optical polarized microscopy and X-ray diffraction) and petrophysical (bulk and real density, open porosity to water and Hg, mechanical strength and ultrasonic velocity) analyses. With this work, it is possible to fill the gap that exists in this field and the characterization of the materials used in the Roman concrete from these two buildings, never previously studied, despite the significance of this archaeological ensemble, declared a World Heritage Site by UNESCO in 1993. The results allowed us to determine the composition of the Roman concrete and to infer the provenance of the aggregates used in these monuments.  相似文献   
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ABSTRACT

An amateur 1969 excavation at the Middle Archaic period Janulis site in Ontario unearthed the skeletal remains of three individuals and a dog. One of these, an adult female with an extensive offering, displayed several changes in the bones of her right arm and shoulder caused by the repetitive and intensive practice of an overhand throwing motion. The association of eight projectile points with her skeleton indicates that the activity was projectile throwing, suggesting a strong emphasis on hunting, normally a masculine role. She also had a turtle-shell rattle, an instrument usually associated with men in that time period. In contrast, the presence of two deer styliform bones in the burial point to a feminine role. These anomalies raise the possibility that this individual had adopted a nonbinary gender status, but the paucity of reliable comparative data makes it difficult to precisely define that status.  相似文献   
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The Irish dimension of Anglo-American relations is a relatively marginalized aspect of the historiography of transatlantic studies. Historians have focused on the role of the Clinton administration in the Northern Ireland “peace process” but previous American contributions also warrant attention. As the Speaker of the United States House of Representatives, Thomas P. “Tip” O’Neill was one of the most prominent Irish-American politicians. This article demonstrates O’Neill's attempts to ensure that the American contribution to the Anglo-Irish process steadily increased, despite the transition from arguably his natural political ally in the President Jimmy Carter administration to President Ronald Reagan in 1981. O’Neill's interest in Northern Ireland and position as speaker helped ensure that Carter's promise of financial aid to Northern Ireland in 1977 following progress in the political process was fulfilled in March 1986.  相似文献   
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