20 research outputs found

    Performance Analysis and Optimization of the Winnow Secret Key Reconciliation Protocol

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    Currently, private communications in public and government sectors rely on methods of cryptographic key distribution that will likely be rendered obsolete the moment a full-scale quantum computer is realized, or efficient classical methods of factoring are discovered. There are alternative methods for distributing secret key material in a post-quantum era. One example of a system capable of securely distributing cryptographic key material, known as Quantum Key Distribution (QKD), is secure against quantum factorization techniques as its security rests on generally accepted laws of quantum physics. QKD protocols typically include a phase called Error Reconciliation, a clear-text classical-channel discussion between legitimate parties of a QKD protocol by which errors introduced in the quantum channel are corrected and the legitimate parties ensure they share identical key material. This work improves one such reconciliation protocol, called Winnow, by examining block-size choices for Winnow and thus increasing QKD key rate. Block sizes are chosen to maximize the probability that each block contains exactly one error. Further analyses of Winnow are provided to characterize the effects of different error distributions on protocol operation and shed light on the time and communication complexities of the Winnow secret key reconciliation protocol

    "Infiltrators" or refugees? An analysis of Israel's policy towards African asylum seekers

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    This article adopts a genealogical approach in examining Israeli immigration policy by focusing on the situation confronting African asylum seekers who have been forced back into Egypt, detained and deported but who have not had their asylum claims properly assessed. Based on immigration policies formulated at the time of Israeli independence, whose principle objective was to secure a Jewish majority state, we argue that Israelā€™s treatment of African asylum seekers as ā€˜infiltratorsā€™/economic migrants stems from an insistence on maintaining immigration as a sovereign issue formally isolated from other policy domains. Such an approach is not only in violation of Israelā€™s commitment to the Refugee Convention, it directly contributes to policies which are ineffective and unduly harsh

    Coral Reefs in the Gulf of Mexico Large Marine Ecosystem: Conservation Status, Challenges, and Opportunities

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    The importance of coral reefs (CR) within marine ecosystems has become widely recognized. Although shallow CR are not as abundant in the Gulf of Mexico (GoM) as in other areas such as the Caribbean, their uniqueness, singularity, isolation, and conservation status make their conservation highly important. Corals and CR, both shallow and deep, are more widely distributed throughout the GoM than previously thought, providing new venues of research but also new challenges for their sustainable management. They are widely present in the three countries circumscribing the GoM (Cuba, Mexico, and the United States). Corals are also distributed throughout different depths, from the keys of Florida and Cuba, to the mesophotic reefs in Flower Garden Banks, Pulley Ridge, and submerged banks in the southern GoM; additional coral presence occurs even beyond mesophotic depths (~30ā€“150 m). Like reefs around the world, they are subject to an increased threat from anthropogenic causes, including overfishing, pollution, and climate change. But there is also hope. Some reefs in the area, such as those in Flower Garden Banks National Marine Sanctuary are probably the best-preserved reefs in the region, with coral cover greater than 50%, which is unusual in the Wider Caribbean. Others are experiencing new protections through the work of government, and local communities. The objectives of this manuscript are to summarize the overall status of corals and CR in the GoM, analyze some of the current and future threats, and explore opportunities for their conservation in the region. Aside from the above mentioned anthropogenic threats bleaching, coral diseases, and hurricanes have been identified as main contributors for CR declines not only in the GoM but abroad; some nowadays present but likely to increase threats are invasion by alien species or by Sargassum spp. Among some of the opportunities identified are to capitalize on existing and emerging multilateral agreements, and initiatives (e.g., GoM Large Marine Ecosystem, trinational sanctuaries agreement); increase financial support for conservation through international initiatives and the private sector; and a need to comprehend the inherent interconnection among corals, CR, and deeper bank ecosystems as they do not function in isolation

    Six priorities to advance the science and practice of coral reef restoration worldwide

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    Coral reef restoration is a rapidly growing movement galvanized by the accelerating degradation of the world's tropical coral reefs. The need for concerted and collaborative action focused on the recovery of coral reef ecosystems coalesced in the creation of the Coral Restoration Consortium (CRC) in 2017. In March 2020, the CRC leadership team met for a biennial review of international coral reef restoration efforts and a discussion of perceived knowledge and implementation bottlenecks that may impair scalability and efficacy. Herein we present six priorities wherein the CRC will foster scientific advancement and collaboration to: (1) increase restoration efficiency, focusing on scale and cost-effectiveness of deployment; (2) scale up larval-based coral restoration efforts, emphasizing recruit health, growth, and survival; (3) ensure restoration of threatened coral species proceeds within a population-genetics management context; (4) support a holistic approach to coral reef ecosystem restoration; (5) develop and promote the use of standardized terms and metrics for coral reef restoration; and (6) support coral reef restoration practitioners working in diverse geographic locations. These priorities are not exhaustive nor do we imply that accomplishing these tasks alone will be sufficient to restore coral reefs globally; rather these are topics where we feel the CRC community of practice can make timely and significant contributions to facilitate the growth of coral reef restoration as a practical conservation strategy. The goal for these collective actions is to provide tangible, local-scale advancements in reef condition that offset declines resulting from local and global stressors including climate change

    Lineages of the Islamic State: an international historical sociology of state (de-)formation in Iraq

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    Existing accounts of the Islamic State (IS) tend to rely on orientalist and technicist assumptions and hence insufficiently sensitive to the historical, sociological, and international conditions of the possibility of IS. The present article provides an alternative account through a conjunctural analysis that is anchored in an international historical sociology of modern Iraq informed by Leon Trotsky's idea of ā€˜uneven and combined developmentā€™. It foregrounds the concatenation of Iraq's contradictory (postā€)colonial nationā€state formation with the neoliberal conjuncture of 1990ā€2014. It shows that the former process involved the tensionā€prone fusion of governing institutions of the modern state and the intermittent but steady reproduction, valorization, and politicization of supraā€national (religiousā€sectarian) and subā€national (ethnoā€tribal) collective identities, which subverted the emergence of an Iraqi nation. The international sanctions regime of the 1990s transformed sectarian and tribal difference into communitarian tension by fatally undermining the integrative efficacy of the Baā€™ath party's authoritarian welfareā€state. Concurrently, the neoā€liberal demolition of the postā€colonial authoritarian welfare states in the region gave rise to the Arab Spring revolutions. The Arab Spring however elicited a successful authoritarian counterā€revolution that eliminated secularā€nationalist forms of oppositional politics. This illiberal neoliberalisation of the region's political economy valorised the religionisation of the domestic effects of the 2003 USā€led destruction of the Iraqi state and its reconstruction on a majoritarian basis favouring the Shiā€™as and hence transforming sectarian tension into sectarian conflict culminating in IS. Thus, IS is, the paper demonstrates, the result of neither an internal cultural pathology nor sheerly external forces. Rather, it is the novel product of an utterly historical congealment of the intrinsically interactive and multilinear dynamics of socioā€political change

    Six priorities to advance the science and practice of coral reef restoration worldwide

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    Coral reef restoration is a rapidly growing movement galvanized by the accelerating degradation of the world's tropical coral reefs. The need for concerted and collaborative action focused on the recovery of coral reef ecosystems coalesced in the creation of the Coral Restoration Consortium (CRC) in 2017. In March 2020, the CRC leadership team met for a biennial review of international coral reef restoration efforts and a discussion of perceived knowledge and implementation bottlenecks that may impair scalability and efficacy. Herein we present six priorities wherein the CRC will foster scientific advancement and collaboration to: (1) increase restoration efficiency, focusing on scale and cost-effectiveness of deployment; (2) scale up larval-based coral restoration efforts, emphasizing recruit health, growth, and survival; (3) ensure restoration of threatened coral species proceeds within a population-genetics management context; (4) support a holistic approach to coral reef ecosystem restoration; (5) develop and promote the use of standardized terms and metrics for coral reef restoration; and (6) support coral reef restoration practitioners working in diverse geographic locations. These priorities are not exhaustive nor do we imply that accomplishing these tasks alone will be sufficient to restore coral reefs globally; rather these are topics where we feel the CRC community of practice can make timely and significant contributions to facilitate the growth of coral reef restoration as a practical conservation strategy. The goal for these collective actions is to provide tangible, local-scale advancements in reef condition that offset declines resulting from local and global stressors including climate change

    Amount of Formal Care Prior to Kindergarten

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