331 research outputs found

    Information-theoretically secure equality-testing protocol with dispute resolution

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    There are often situations where two remote users each have data, and wish to (i) verify the equality of their data, and (ii) whenever a discrepancy is found afterwards, determine which of the two modified his data. The most common example is where they want to authenticate messages they exchange. Another possible example is where they have a huge database and its mirror in remote places, and whenever a discrepancy is found between their data, they can determine which of the two users is to blame. Of course, if one is allowed to use computational assumptions, this function can be realized readily, e.g., by using digital signatures. However, if one needs information-theoretic security, there is no known method that realizes this function efficiently, i.e., with secret key, communication, and trusted third parties all being sufficiently small. In order to realize this function efficiently with information-theoretic security, we here define the ``equality-testing protocol with dispute resolution'' as a new framework. The most significant difference between our protocol and the previous methods with similar functions is that we allow the intervention of a trusted third party when checking the equality of the data. In this new framework, we also present an explicit protocol that is information-theoretically secure and efficient.Comment: 7 pages, 2 figure

    Advantage of the key relay protocol over secure network coding

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    The key relay protocol (KRP) plays an important role in improving the performance and the security of quantum key distribution (QKD) networks. On the other hand, there is also an existing research field called secure network coding (SNC), which has similar goal and structure. We here analyze differences and similarities between the KRP and SNC rigorously. We found, rather surprisingly, that there is a definite gap in security between the KRP and SNC; that is, certain KRPs achieve better security than any SNC schemes on the same graph. We also found that this gap can be closed if we generalize the notion of SNC by adding free public channels; that is, KRPs are equivalent to SNC schemes augmented with free public channels.Comment: 10 pages, 11 figure

    A Target Site for Spontaneous Insertion of IS10 Element in pUC19 DNA Located within Intrinsically Bent DNA

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    Residual insertion sequence elements (IS elements) in Escherichia coli strains that are commonly used for DNA cloning are known to cause cloning artifacts by transposing themselves into the recombinant DNA fragments. In such cases, chance insertion of IS elements may occur at integration sites in the cloning targets, which in the case of the IS10 element is a 9-bp consensus sequence. We report here that the integration of IS10-related DNA sequences into the pUC19 cloning vector and its derivative occurred with considerable frequency in E. coli strains JM107 and DH10B, with duplication of a 9-bp segment (TCTAAAGTA). Notably, native polyacrylamide gel electrophoresis revealed that intrinsically bent DNA flanks the insertion site

    Monthly minodronate inhibits bone resorption to a greater extent than does monthly risedronate

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    AbstractAs a bisphosphonate, minodronate (MIN) is one of the strongest inhibitors of bone resorption. However, there have been no reports directly comparing the antiresorptive effects of monthly MIN with those of monthly risedronate (RIS). We enrolled 30 cases of osteoporosis (OP; 16 in the MIN group [mean age: 68.2 years] and 14 in the RIS group [mean age: 68.1 years]) to investigate the early effects of treatment by monthly MIN or RIS over a 4-month period using bone turnover marker values. Only female patients were enrolled to avoid gender bias. Urinary cross-linked N-telopeptide of type I collagen (NTX) before treatment and at 1, 2, and 4 months of therapy, as well as serum bone alkaline phosphatase and alkaline phosphatase before treatment and at 4 months afterwards, were evaluated. All bone turnover marker values were significantly decreased at 4 months in both groups. The changes in urinary NTX at the study end point for RIS and MIN were −30.1% and −63.1%, respectively. From 2 months of treatment, the antiresorptive effects on urinary NTX by MIN were significantly higher than those by RIS, indicating that MIN more immediately and strongly inhibited bone absorption. Thus, monthly MIN seems to suppress bone resorption faster and more strongly than RIS in OP treatment

    Effects of fruit skin and water temperature during soaking before germination on the emergence rates of common buckwheat

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    The studies focused effects of the presence of fruit skin (hull or pericarp) and water temperature during water soaking before germination on the emergence rates of common buckwheat (Fagophyrum esculentum Moench) after seeding. We aimed to understand the mechanisms underlying the poor emergence rates that have been observed after water flooding before germination. Shinano No.1 was exposed to water soaking treatments at temperatures of 10,15,20, or 25℃ for 3 days. After soaking, the seeds were grown at 20℃, and the percentages of emerged seedlings were investigated 7 days after seeding. Dehulled seeds and normal seeds were soaked for 4 days at 25℃, and the contents of dissolved oxygen were measured in the water. The emergence rates of normal intact seeds (fruits)decreased significantly (p<0.01)with an increase in soaking water temperature before germination. The emergence rates of dehulled seeds improved after removing the fruit skin, and it reached 70%,even at 25℃.Soaking treatment for 96 h at 25℃ decreased the emergence rates of normal seeds and dehulled seeds. The emergence rate of normal seeds was significantly lower than that of dehulled seeds (p<0.001). Moreover, there was no difference in the emergence rates of dehulled seeds between plots with or without daily water replacement. The contents of dissolved oxygen in the water at 25℃ did not differ between normal seeds and dehulled seeds after 50h. These results suggested that high temperatures affected embryo viability and that the relative mechanical resistance of the fruit skin on the embryo directly affected the seed emergence rate.Article信州大学農学部AFC報告 13: 113-118 (2015)departmental bulletin pape

    High-fidelity conversion of photonic quantum information to telecommunication wavelength with superconducting single-photon detectors

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    We experimentally demonstrate a high-fidelity visible-to-telecommunication wavelength conversion of a photon by using a solid-state-based difference frequency generation. In the experiment, one half of a pico-second visible entangled photon pair at 780 nm is converted to a 1522-nm photon, resulting in the entangled photon pair between 780 nm and 1522 nm. Using superconducting single-photon detectors with low dark count rates and small timing jitters, we selectively observed well-defined temporal modes containing the two photons. We achieved a fidelity of 0.93±0.040.93 \pm 0.04 after the wavelength conversion, indicating that our solid-state-based scheme can be used for faithful frequency down-conversion of visible photons emitted from quantum memories composed of various media.Comment: 5 pages, 4 figure

    Influence of organic fertilizer on rhizome yield and α-tocopherol content of Codonopsis lanceolata

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    Codonopsis lanceolata (Sieb. et Zucc.) Trautv. is a valuable wild vegetable in East Asian countries, especially Korea. We investigated effects of organic fertilizer application on rhizome yield and quality under Andosol soil conditions in the AFC field of Shinshu University. Commercial barnyard manure, which was fermented with crushed bark and beef cattle dung, and Japanese oak leaf mold were applied at the rates of 0, 5, 10, 15, and 20 g m-2. Barnyard manure increased the fresh weight yield of rhizomes but decreased the DL-α-tocopherol (vitamin E) content. The rhizome yield was drastically influenced by the C/N ratio of the soil from the surface to 30 cm below ground level that was controlled by the application ratio of barnyard manure to leaf mold. Total N, soluble P, exchangeable K, Ca, and Mg did not significantly affect the rhizome yield. There was a significant negative correlation between the rhizome fresh weight and vitamin E content at harvest time. The highest vitamin E content of 9-10 mg 100 g-1 dry matter was obtained at a leaf mold application rate of 10 g m-1. Nitrogen supply from the soil to plants primarily influenced the yield and quality of rhizomes as vegetables or drugs. The vitamin E content under a higher soil C/N ratio was the highest among commercial vegetables available in common Japanese food markets.Article信州大学農学部AFC報告 10: 1-7(2012)departmental bulletin pape
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