213 research outputs found

    Ideal Tightly Couple (t,m,n) Secret Sharing

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    As a fundamental cryptographic tool, (t,n)-threshold secret sharing ((t,n)-SS) divides a secret among n shareholders and requires at least t, (t<=n), of them to reconstruct the secret. Ideal (t,n)-SSs are most desirable in security and efficiency among basic (t,n)-SSs. However, an adversary, even without any valid share, may mount Illegal Participant (IP) attack or t/2-Private Channel Cracking (t/2-PCC) attack to obtain the secret in most (t,n)-SSs.To secure ideal (t,n)-SSs against the 2 attacks, 1) the paper introduces the notion of Ideal Tightly cOupled (t,m,n) Secret Sharing (or (t,m,n)-ITOSS ) to thwart IP attack without Verifiable SS; (t,m,n)-ITOSS binds all m, (m>=t), participants into a tightly coupled group and requires all participants to be legal shareholders before recovering the secret. 2) As an example, the paper presents a polynomial-based (t,m,n)-ITOSS scheme, in which the proposed k-round Random Number Selection (RNS) guarantees that adversaries have to crack at least symmetrical private channels among participants before obtaining the secret. Therefore, k-round RNS enhances the robustness of (t,m,n)-ITOSS against t/2-PCC attack to the utmost. 3) The paper finally presents a generalized method of converting an ideal (t,n)-SS into a (t,m,n)-ITOSS, which helps an ideal (t,n)-SS substantially improve the robustness against the above 2 attacks

    Critical Theory in Regressive Times: Liberalism, Global Populism and the “White Left” in the Twenty-First Century

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    In this paper, I consider not only the crisis in conservative neoliberalism and free market economics, but a crisis of representation and plausibility in progressive new liberalism; a situation which leads to deadlock for progressivism in which things cannot progress. In order to address this state of crisis in the global perception of the “white left,” Critical Theory, as a mode of Western liberal thought, needs to rethink the direction of its own criticism. Additionally, Critical Theory needs to adjust its focus to respond to the deadlock presented by the rise of right-wing populism and the derogation of liberal values in these regressive times (I refer antonymically, here, to Jürgen Habermas’s use of the term “progressive”). The radical democratic ideal advocated by Habermas, comprising universal equality and emancipation, should still be the goal for liberalism, and for Critical Theory, but first of all, the achievements and advances liberal progressivism has already made need to be secured to prevent society from regressing. This does not mean making a choice between neoliberalism and authoritarianism, but that a new paradigm of thinking is due. I argue that universality is anterior to cultural pluralism, as are social topics to cultural issues, and justice of distribution to justice of identity. In the complex world of modernity, good things do not come together if there is conflict between desirable values, so choices need to be made: a ranking of real, material conditions is necessary, to ensure cohesion and progression

    Transmission Dynamics of the Recently-Identified BYD Virus Causing Duck Egg-Drop Syndrome

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    Baiyangdian (BYD) virus is a recently-identified mosquito-borne flavivirus that causes severe disease in ducks, with extremely rapid transmission, up to 15% mortality within 10 days and 90% reduction in egg production on duck farms within 5 days of infection. Because of the zoonotic nature of flaviviruses, the characterization of BYD virus and its epidemiology are important public health concerns. Here, we develop a mathematical model for the transmission dynamics of this novel virus. We validate the model against BYD outbreak data collected from duck farms in Southeast China, as well as experimental data obtained from an animal facility. Based on our model, the basic reproductive number of BYD virus is high (R0 = 21) indicating that this virus is highly transmissible, consistent with the dramatic epidemiology observed in BYDV-affected duck farms. Our results indicate that younger ducks are more vulnerable to BYD disease and that ducks infected with BYD virus reduce egg production (to about 33% on average) for about 3 days post-infection; after 3 days infected ducks are no longer able to produce eggs. Using our model, we predict that control measures which reduce contact between mosquitoes and ducks such as mosquito nets are more effective than insecticides

    RHFedMTL: Resource-Aware Hierarchical Federated Multi-Task Learning

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    The rapid development of artificial intelligence (AI) over massive applications including Internet-of-things on cellular network raises the concern of technical challenges such as privacy, heterogeneity and resource efficiency. Federated learning is an effective way to enable AI over massive distributed nodes with security. However, conventional works mostly focus on learning a single global model for a unique task across the network, and are generally less competent to handle multi-task learning (MTL) scenarios with stragglers at the expense of acceptable computation and communication cost. Meanwhile, it is challenging to ensure the privacy while maintain a coupled multi-task learning across multiple base stations (BSs) and terminals. In this paper, inspired by the natural cloud-BS-terminal hierarchy of cellular works, we provide a viable resource-aware hierarchical federated MTL (RHFedMTL) solution to meet the heterogeneity of tasks, by solving different tasks within the BSs and aggregating the multi-task result in the cloud without compromising the privacy. Specifically, a primal-dual method has been leveraged to effectively transform the coupled MTL into some local optimization sub-problems within BSs. Furthermore, compared with existing methods to reduce resource cost by simply changing the aggregation frequency, we dive into the intricate relationship between resource consumption and learning accuracy, and develop a resource-aware learning strategy for local terminals and BSs to meet the resource budget. Extensive simulation results demonstrate the effectiveness and superiority of RHFedMTL in terms of improving the learning accuracy and boosting the convergence rate.Comment: 11 pages, 8 figure

    Response of Reproductive Traits and Longevity of Beet Webworm to Temperature, and Implications for Migration

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    Beet webworm, Loxostege sticticalis (L.) is a facultative long-distance migratory insect pest in many regions between 36° and 55° N latitude. The outbreaks of larvae are closely related to temperatures encountered by the immigrant adult. But mechanisms linking population outbreaks and migration are not well understood. We investigated the effect of exposing adults to constant temperatures from 14 to 34°C on mating, oviposition, and longevity. Our results showed that both mating percentage and frequency were highest at 22–26°C and decreased at temperatures outside this optimal range. Time of night when mating began was delayed at higher temperatures, while mating duration progressively decreased with increasing temperature. Both preoviposition period (POP) and oviposition period decreased linearly with increasing temperature. Peak daily and lifetime fecundity were highest at 22–26°C and declined at temperatures outside this range, suggesting that 22–26°C is the optimal thermal range for oviposition. Adult longevity was negatively correlated with temperature. Males lived longer than females at lower temperatures, but females lived longer than males in the 30–34°C treatments. Together, our findings suggest that reproduction occurs when the prevailing temperature is around 22–26°C, and that migratory flight is favored outside this range via increases in POP and proportion of virgins. We predict that larval damage or outbreaks of L. sticticalis will occur only in areas where the prevailing temperature is around 22–26°C, which provides a key basis for the prediction of population outbreaks in areas of immigration

    A cadherin-like protein influences Bacillus thuringiensis Cry1Ab toxicity in the oriental armyworm, Mythimna separata

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    Cadherins comprise a family of calcium-dependent cell adhesion proteins that act in cell–cell interactions. Cadherin-like proteins (CADs) in midguts of some insects act as receptors that bind some of the toxins produced by the Bacillus thuringiensis (Bt). We cloned a CAD gene associated with larval midguts prepared from Mythimna separata. The full-length cDNA (MsCAD1, GenBank Accession No. JF951432) is 5642 bp, with an open reading frame encoding a 1757 amino acid and characteristics typical of insect CADs. Expression of MsCAD1 is predominantly in midgut tissue, with highest expression in the 3rd- to 6th-instars and lowest in newly hatched larvae. Knocking-downMsCAD1 decreased Cry1Ab susceptibility, indicated by reduced developmental time, increased larval weight and reduced larval mortality. We expressed MsCAD1 in E. coli and recovered the recombinant protein, rMsCAD1, which binds Cry1Ab toxin. Truncation analysis and binding experiments revealed that a contiguous 209-aa, located in CR11 and CR12, is the minimal Cry1Ab binding region. These results demonstrate that MsCAD1 is associated with Cry1Ab toxicity and is one of the Cry1Ab receptors in this insect. The significance of this work lies in identifying MsCAD1 as a Cry1Ab receptor, which helps understand the mechanism of Cry1Ab toxicity and of potential resistance to Bt in M. separata

    Multicystic Changes of Juvenile Nasopharyngeal Angiofibroma: The First Case Report in the Literature

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    Multicystic changes of juvenile nasopharyngeal angiofibroma: the first case report in the literature. Otolaryngologists, pathologists, and radiologists had better pay attention to this infrequent incidence

    Fully Collusion Resistant Trace-and-Revoke Functional Encryption for Arbitrary Identities

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    Functional Encryption (FE) has been extensively studied in the recent years, mainly focusing on the feasibility of constructing FE for general functionalities, as well as some realizations for restricted functionalities of practical interest, such as inner-product. However, little consideration has been given to the issue of key leakage on FE. The property of FE that allows multiple users to obtain the same functional keys from the holder of the master secret key raises an important problem: if some users leak their keys or collude to create a pirated decoder, how can we identify at least one of those users, given some information about the compromised keys or the pirated decoder? Moreover, how do we disable the decryption capabilities of those users (i.e. traitors)? Two recent works have offered potential solutions to the above traitor scenario. However, the two solutions satisfy weaker notions of security and traceability, can only tolerate bounded collusions (i.e., there is an a priori bound on the number of keys the pirated decoder obtains), or can only handle a polynomially large universe of possible identities. In this paper, we study trace-and-revoke mechanism on FE and provide the first construction of trace-and-revoke FE that supports arbitrary identities, is both fully collusion resistant and fully anonymous. Our construction relies on a generic transformation from revocable predicate functional encryption with broadcast (RPFE with broadcast, which is an extension of revocable predicate encryption with broadcast proposed by Kim and J. Wu at ASIACRYPT\u272020) to trace-and-revoke FE. Since this construction admits a generic construction of trace-and-revoke inner-product FE (IPFE), we instantiate the trace-and-revoke IPFE from the well-studied Learning with Errors (LWE). This is achieved by proposing a new LWE-based attribute-based IPFE (ABIPFE) scheme to instantiate RPFE with broadcast
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