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771.
The United States (US) launch infrastructure is at a crisis point. Human access to space embodied in the Space Shuttle is due to be phased out by 2010. Currently, there are no heavy lift, 100 ton class launchers to support the US national vision for space exploration. Medium and large expendable launch providers, Boeing's Delta IV, and Lockheed-Martin's Atlas V Evolved Expendable Launch Vehicles are so expensive that the Delta no longer carries commercial payloads and the Atlas is unlikely to show significant growth without equally significant cost reductions and commercial traffic growth. This set of circumstances questions US dependence on these launch vehicles for national security purposes. High cost growth also exists with small launch vehicles, such as Pegasus, and the promising new field of small and microsatellites is little developed in the US, while foreign efforts, particularly European, are expanding largely on the availability of low-cost Russian boosters. One bright point is the emerging private sector, which is initially pursuing suborbital or small lift capabilities. Although such vehicles support very limited US Department of Defense or National Aeronautics and Space Administration spaceflight needs, they do offer potential technology demonstration stepping stones to more capable systems needed in the future of both agencies. This article outlines the issues and potential options for the US Government to address these serious shortcomings.  相似文献   
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The Arab‐Israeli peace process pointed to a resolution of the Middle East's most persistent conflict, as the Rabin and Peres governments developed a sensitivity to the Arab‐Israeli ‘security dilemma’, but by 1996 the process was deadlocked. Events stalled progress, but so did ingrained attitudes that continued to shape policy that was inconsistent with the peace process. The following article explains some of the Realist norms and values at the root of security thinking in Israel, and charts their inertia in Israeli policy during the peace process, focusing on its approach to Lebanon. The article gives an insight into why Rabin and his successors struggled to find an alternative policy towards Lebanon, and how this prolonged the Arab‐Israeli conflict. The efforts of the Netanyahu and Barak governments to find a solution to the policy problem of Lebanon are outlined.  相似文献   
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I examine the ways in which the global financial crisis that began in 2007, and whose effects arguably condition policymaking to the present day, affected the ongoing global power transition as manifested by the unilateral decisions undertaken by official agencies comprising national regulatory states. The theory of that power transition articulated in the overview paper of this Special Issue is reinterpreted to take into account the circumstances of that crisis. Empirical evidence on the propensity to discriminate against foreign commercial interests by the BRICS, Turkey, the European Union, and the United States during the years 2008 to 2017 at, and behind, the border is employed to identify a group of six potential rule-shapers and two possible sham rule-takers.  相似文献   
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Direct empirical testing of forensic DNA micro-probabilities has proved difficult. Substantial support for the population genetic models on which these micro-probabilities are based has come from powerful but indirect means. However for many people empirical testing rather than models remains the ideal.Following the example set by Weir and Evett we report here a large-scale empirical test of a population genetic model incorporating substructure and relatedness. Given that all models represent simplifications of reality the fit of observed and prediction is remarkable and gives substantial support to the reliability of current methods.  相似文献   
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