16 research outputs found

    A conference key distribution system based on cross-product

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    AbstractExtended from the Diffie-Hellman public key distribution system (PKDS), we propose a conference key distribution system (CKDS) based on the cross-product operations on row vectors over a Galois field GF(P), where P is a prime number. In our CKDS, the chairperson computes a conference key CK and then embeds it to some public interpolating polynomials to let only the legal intended principals recover CK, while the illegal intended principals can not. From the public parameters, an intruder or any intended principal in the network does not know how many and who are the legal intended principals in the conference. Furthermore, since the construction of the CK does not interfere with the secret keys of the intended principals, any intended principals in the network has no useful information for revealing any other principals' secret keys. Besides, our CKDS can be implemented practically

    Association between plasma levels of hyaluronic acid and functional outcome in acute stroke patients

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    BACKGROUND: Activation of hyaluronic acid (HA) and associated enzyme synthesis has been demonstrated in experimental stroke animal models. Our study aimed to investigate the plasma levels of HA in acute stroke patients and the associations between HA levels and functional outcome. METHODS: This was a multicenter case–control study. Acute stroke patients and age- and sex-matched non-stroke controls were recruited. Plasma levels of HA in acute stroke patients were determined at <48 hours and at 48 to 72 hours after stroke onset by standard ELISA. Favorable functional outcome was defined as modified Rankin scale ≤2 at 3 months after stroke. RESULTS: The study included 206 acute stroke patients, including 43 who had intracerebral hemorrhage and 163 who had ischemic stroke, and 159 controls. The plasma levels of HA in the acute stroke patients were significantly higher than those in the controls (219.7 ± 203.4 ng/ml for <48 hours and 343.1 ± 710.3 ng/ml for 48 to 72 hours versus 170.4 ± 127.9 ng/ml in the controls; both P < 0.05). For intracerebral hemorrhage patients, HA ≤500 ng/ml (<48 hours) was an independent favorable outcome predictor (P = 0.016). For ischemic stroke patients, an inverted U-shaped association between plasma HA (48 to 72 hours) and outcome was noted, indicating that ischemic stroke patients with too high or too low plasma HA levels tended to have an unfavorable outcome. CONCLUSION: HA plasma level was elevated in patients with acute stroke, and can predict 3-month functional outcome, particularly for patients with intracerebral hemorrhage

    Genomic Insights into the Formation of Human Populations in East Asia

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    厦门大学人类学研究所、厦门大学生命科学学院细胞应激生物学国家重点实验室王传超教授课题组与哈佛医学院David Reich教授团队合作,联合全球43个单位的85位共同作者组成的国际合作团队通过古DNA精细解析东亚人群形成历史。研究人员利用古DNA数据检验了东亚地区农业和语言共扩散理论,综合考古学、语言学等证据,该研究系统性地重构了东亚人群的形成、迁徙和混合历史。这是目前国内开展的东亚地区最大规模的考古基因组学研究,此次所报道的东亚地区古人基因组样本量是以往国内研究机构所发表的样本量总和的两倍,改变了东亚地区尤其是中国境内考古基因组学研究长期滞后的局面。 该研究是由王传超教授团队与哈佛医学院(David Reich教授)、德国马普人类历史科学研究所(Johannes Krause教授)、复旦大学现代人类学教育部重点实验室(李辉教授和金力院士)、维也纳大学进化人类学系(Ron Pinhasi副教授)、南洋理工大学人文学院(Hui-Yuan Yeh助理教授)、俄罗斯远东联邦大学科学博物馆(Alexander N Popov研究员)、西安交通大学(张虎勤教授)、蒙古国国家博物馆研究中心、乌兰巴托国立大学考古系、华盛顿大学人类学系、台湾成功大学考古所、加州大学人类学系等全球43个单位的85位共同作者组成的国际合作团队联合完成的。厦门大学人类学研究所、厦门大学生命科学学院细胞应激生物学国家重点实验室为论文第一完成单位。厦门大学人类学研究所韦兰海副教授、胡荣助理教授、郭健新博士后、何光林博士后和杨晓敏硕士参与了研究工作。The deep population history of East Asia remains poorly understood due to a lack of ancient DNA data and sparse sampling of present-day people1,2. We report genome-wide data from 166 East Asians dating to 6000 BCE-1000 CE and 46 present-day groups. Hunter-gatherers from Japan, the Amur River Basin, and people of Neolithic and Iron Age Taiwan and the Tibetan plateau are linked by a deeply-splitting lineage likely reflecting a Late Pleistocene coastal migration. We follow Holocene expansions from four regions. First, hunter-gatherers of Mongolia and the Amur River Basin have ancestry shared by Mongolic and Tungusic language speakers but do not carry West Liao River farmer ancestry contradicting theories that their expansion spread these proto-languages. Second, Yellow River Basin farmers at ~3000 BCE likely spread Sino-Tibetan languages as their ancestry dispersed both to Tibet where it forms up ~84% to some groups and to the Central Plain where it contributed ~59-84% to Han Chinese. Third, people from Taiwan ~1300 BCE to 800 CE derived ~75% ancestry from a lineage also common in modern Austronesian, Tai-Kadai and Austroasiatic speakers likely deriving from Yangtze River Valley farmers; ancient Taiwan people also derived ~25% ancestry from a northern lineage related to but different from Yellow River farmers implying an additional north-to-south expansion. Fourth, Yamnaya Steppe pastoralist ancestry arrived in western Mongolia after ~3000 BCE but was displaced by previously established lineages even while it persisted in western China as expected if it spread the ancestor of Tocharian Indo-European languages. Two later gene flows affected western Mongolia: after ~2000 BCE migrants with Yamnaya and European farmer ancestry, and episodic impacts of later groups with ancestry from Turan.We thank David Anthony, Ofer Bar-Yosef, Katherine Brunson, Rowan Flad, Pavel Flegontov,Qiaomei Fu, Wolfgang Haak, Iosif Lazaridis, Mark Lipson, Iain Mathieson, Richard Meadow,Inigo Olalde, Nick Patterson, Pontus Skoglund, Dan Xu, and the four reviewers for valuable comments. We thank Naruya Saitou and the Asian DNA Repository Consortium for sharing genotype data from present-day Japanese groups. We thank Toyohiro Nishimoto and Takashi Fujisawa from the Rebun Town Board of Education for sharing the Funadomari Jomon samples, and Hideyo Tanaka and Watru Nagahara from the Archeological Center of Chiba City who are excavators of the Rokutsu Jomon site. The excavations at Boisman-2 site (Boisman culture), the Pospelovo-1 site (Yankovsky culture), and the Roshino-4 site (Heishui Mohe culture) were funded by the Far Eastern Federal University and the Institute of History,Archaeology and Ethnology Far Eastern Branch of the Russian Academy of Sciences; research on Pospelovo-1 is funded by RFBR project number 18-09-40101. C.C.W was funded by the Max Planck Society, the National Natural Science Foundation of China (NSFC 31801040), the Nanqiang Outstanding Young Talents Program of Xiamen University (X2123302), the Major project of National Social Science Foundation of China (20&ZD248), a European Research Council (ERC) grant to Dan Xu (ERC-2019-ADG-883700-TRAM) and Fundamental Research Funds for the Central Universities (ZK1144). O.B. and Y.B. were funded by Russian Scientific Foundation grant 17-14-01345. H.M. was supported by the grant JSPS 16H02527. M.R. and C.C.W received funding from the ERC under the European Union’s Horizon 2020 research and innovation program (grant No 646612) to M.R. The research of C.S. is supported 30 by the Calleva Foundation and the Human Origins Research Fund. H.L was funded NSFC (91731303, 31671297), B&R International Joint Laboratory of Eurasian Anthropology (18490750300). J.K. was funded by DFG grant KR 4015/1-1, the Baden Württemberg Foundation, and the Max Planck Institute. Accelerator Mass Spectrometry radiocarbon dating work was supported by the National Science Foundation (NSF) (BCS-1460369) to D.J.K. and B.J.C. D.R. was funded by NSF grant BCS-1032255, NIH (NIGMS) grant GM100233, the Paul M. Allen Frontiers Group, John Templeton Foundation grant 61220, a gift from Jean-Francois Clin, and the Howard Hughes Medical Institute. 该研究得到了国家自然科学基金“中国东南各族群的遗传混合”、国家社科基金重大项目“多学科视角下的南岛语族的起源和形成研究”、厦门大学南强青年拔尖人才支持计划A类、中央高校基本科研业务费等资助

    Mental poker game based on a bit commitment scheme through network

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    Abstract There are many schemes proposed on mental poker so far. Most of them are based on the composition of each player&apos;s private permutation of cards. Yet, each one is either too complex or has some drawbacks in it. In other words, no solution has come to reality. In this paper, we propose a permutation-free method, i.e. a bit commitment scheme, along with the RSA cryptosystem (Cryptography-Theory and Practice, CRC Press, Boca Raton, 1995; Public-key, Cryptography, Springer, Berlin, 1996) to implement the mental poker game. It is not only simple but also concise in concept.

    A DL Based Short Strong Designated Verifier Signature Scheme with Low Computation

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    A designated verifier signature (DVS) scheme is a special type of digital signature scheme without the property of non-repudiation. Such schemes only allow the designated verifier to validate the signer’s signature. Meanwhile, the designated verifier is not able to convince any third party of the signature’s actual signer, since he can also generate a computationally indistinguishable one compared to the received signature. A strong designated verifier signature (SDVS) scheme further prohibits anyone except for the intended verifier from validating the signature as it requires the designated verifier’s private key to finish the verification process. In this paper, we propose an efficient short SDVS scheme with low computation costs. Unlike many SDVS schemes primarily implemented on pairingbased cryptosystems, we focus on the discrete logarithms (DL) based system. Compared with those DL based SDVS schemes, ours provides better functionalities and efficiency and hence benefits the practical applications. In addition, the security requirement of unforgeability against existential forgery on adaptive chosen-message attacks (EU-CMA) is proved in the random oracle model

    Analyze SHA-1 in message schedule

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    Abstract Wang et al have found a family of collisions in MD5. They reported their method to find a collision efficiently in SHA, and also to find a collision in SHA-1 within 2 69 hash steps in February 2005. In fact, we can still discover the decay phenomenon with the application of a message schedule&apos;s judgment proposed in this work when inspection how SHA-1 generates message schedule actually. Therefore, we would like to introduce two SHA-1 corrections to enhance the security of SHA-1
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