116 research outputs found

    How Has Japanese Social Studies Perceived about “Learning about Controversial Issues”?: Literature review on the Japanese articles

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    Currently, there is a growing policy interest in learning about controversial issue as part of voting learning against a backdrop of social change. However, the study of controversial issues in social studies education began already in the 1970s, and a certain amount of research has been accumulated up to the present. This paper examines the previous studies related to ‘learning about controversial issues’ from the perspective of “educational borrowing” in order to the characteristics of Japanese educational research. A literature search of CiNii and Google scholar database was conducted, using the following key words: Ronsomondai (Controversial Issues), Gakushu (Learning), Syakaika (social studies), Jugyo (Lesson). The findings reveal that these studies have been reflected by Japanese context around academic, policy and practical context. Learning about controversial issues could support existing social studies theories, but it also gives questions existing social studies practice

    Negative regulation of hepatitis B virus replication by forkhead box protein A in human hepatoma cells

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    AbstractHepatitis B virus (HBV) replication is controlled by liver-enriched transcriptional factors, including forkhead box protein A (FOXA) members. Here, we found that FOXA members are directly and indirectly involved in HBV replication in human hepatic cells. HBV replication was elevated in HuH-7 treated with individual FOXA members-specific siRNA. Reciprocally, the downregulation of HBV replication was observed in FOXA-induced HuH-7. However, the mechanism of downregulation is different among FOXA members at the level of HBV RNA transcription, such as precore/pg RNA and 2.1kb RNA. In addition, FOXA1 and FOXA2 suppressed nuclear hormone receptors, such as HNF4α, that are related to HBV replication

    Security Analysis of Cryptosystems Using Short Generators over Ideal Lattices

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    In this paper, we analyze the security of cryptosystems using short generators over ideal lattices such as candidate multilinear maps by Garg, Gentry and Halevi and fully homomorphic encryption by Smart and Vercauteren. Our approach is based on a recent work by Cramer, Ducas, Peikert and Regev on analysis of recovering a short generator of an ideal in the qq-th cyclotomic field for a prime power qq. In their analysis, implicit lower bounds of the special values of Dirichlet LL-functions at 1 are essentially used for estimating some sizes of the dual basis in the log-unit lattice of the qq-th cyclotomic field. Our main contribution is to improve Cramer et al.\u27s analysis by giving explicit lower and upper bounds of the special values of Dirichlet LL-functions at 1 for any non-trivial even Dirichlet characters modulo qq. Moreover, we give various experimental evidence that recovering short generators of principle ideals in 2k2k-th cyclotomic fields for k10k \geq 10 is succeeded with high probability. As a consequence, our analysis suggests that the security of the above cryptosystems based on the difficulty of recovering a short generator is reduced to solving the principal ideal problem under the number theoretical conjecture so-called Weber\u27s class number problem

    Cryptanalysis of a public key cryptosystem based on Diophantine equations via weighted LLL reduction

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    Post-quantum cryptography now plays a central role in cryptography. Many candidates of post-quantum cryptosystems (PQC) have been already proposed but require public keys of large sizes. Constructing PQC with public keys of small sizes is strongly desired. In [Oku15], Okumura proposed a public key cryptosystem based on the difficulty of solving Diophantine equations of degree increasing type (DEC for short). DEC is proposed as an analogue of the Algebraic Surface Cryptosystem [AGM09]. DEC has been expected to avoid the analogues of all attacks against ASC (and the previous versions of ASC). Moreover, DEC has been expected to be a candidate of PQC and to achieve the high security with public keys of small sizes, e.g., about 1;200 bits with 128 bit security. In this paper, we propose a polynomial time attack against DEC. We show that the security of DEC depends on the difficulty of finding special (relatively) short vectors in some lattices obtained from a public key and a ciphertext. The most important target vector in our attack is not necessarily a shortest vector in a lattice of low rank but only some entries are relatively small. In our attack, the LLL algorithm with respect to well-known norms such as the pp-norms (1p11 \leq p \leq 1) does not seem to work well for finding such vectors. The most technical point of our method is to heuristically find a special norm, which we call a weighted norm, such that the most important target vector becomes a (nearly) shortest vector in a lattice of low rank. We call the LLL algorithm with respect to a weighted norm the ``weighted LLL algorithm in this paper. Our experimental results by a standard PC with Magma suggest that our attack via the weighted LLL algorithm can break the one-wayness of DEC for 128 bit security proposed in [Oku15] with sufficiently high probability

    Preoperative Graft Volume Assessment with 3D-CT Volumetry in Living-Donor Lobar Lung Transplantations

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    To determine the effectiveness of living-donor lobar lung transplantation (LDLLT), it is necessary to predict the recipient's postoperative lung function. Traditionally, Date's formula, also called the segmental ratio, has used the number of lung segments to estimate the forced vital capacity (FVC) of grafts in LDLLT. To provide a more precise estimate of graft FVC, we calculated the volumes of the lower lobe and total lung using three-dimensional computed tomography (3D-CT) and the volume ratio between them. We calculated the volume ratio in 52 donors and tested the difference between the segmental volume ratios with a one-tailed t-test. We also calculated the predicted graft FVC in 21 LDLLTs using the segmental ratio pFVC(c) and the volume ratio pFVC(v), and then found the Pearson's correlation coefficients for both pFVC(c) and pFVC(v) with the recipients' actual FVC (rFVC) measured spirometrically 6 months after surgery. Significant differences were found between the segmental ratio and the average volume ratio for both sides (right, p=0.03;left, p=0.0003). Both pFVC(c) and pFVC(v) correlated significantly with rFVC at 6 months after surgery (p=0.007 and 0.006). Both the conventional and the volumetric methods provided FVC predictions that correlated significantly with measured postoperative FVC

    The Maximum Standardized Uptake Value Is More Reliable Than Size Measurement in Early Follow-up to Evaluate Potential Pulmonary Malignancies Following Radiofrequency Ablation

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    We retrospectively evaluated the accumulation of fluorodeoxy glucose (FDG) in pulmonary malignancies without local recurrence during 2-year follow-up on positron emission tomography (PET)/computed tomography (CT) after radiofrequency ablation (RFA). Thirty tumors in 25 patients were studied (10 non-small cell lung cancers;20 pulmonary metastatic tumors). PET/CT was performed before RFA, 3 months after RFA, and 6 months after RFA. We assessed the FDG accumulation with the maximum standardized uptake value (SUVmax) compared with the diameters of the lesions. The SUVmax had a decreasing tendency in the first 6 months and, at 6 months post-ablation, FDG accumulation was less affected by inflammatory changes than at 3 months post-RFA. The diameter of the ablated lesion exceeded that of the initial tumor at 3 months post-RFA and shrank to pre-ablation dimensions by 6 months post-RFA. SUVmax was more reliable than the size measurements by CT in the first 6 months after RFA, and PET/CT at 6 months post-RFA may be more appropriate for the assessment of FDG accumulation than that at 3 months post-RFA

    A Public-key Encryption Scheme Based on Non-linear Indeterminate Equations (Giophantus)

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    In this paper, we propose a post-quantum public-key encryption scheme whose security depends on a problem arising from a multivariate non-linear indeterminate equation. The security of lattice cryptosystems, which are considered to be the most promising candidate for a post-quantum cryptosystem, is based on the shortest vector problem or the closest vector problem in the discrete linear solution spaces of simultaneous equations. However, several improved attacks for the underlying problems have recently been developed by using approximation methods, which result in requiring longer key sizes. As a scheme to avoid such attacks, we propose a public-key encryption scheme based on the smallest solution problem in the non-linear solution spaces of multivariate indeterminate equations that was developed from the algebraic surface cryptosystem. Since no efficient algorithm to find such a smallest solution is currently known, we introduce a new computational assumption under which proposed scheme is proven to be secure in the sense of IND-CPA. Then, we perform computational experiments based on known attack methods and evaluate that the key size of our scheme under the linear condition. This paper is a revised version of SAC2017

    A Japanese History lesson for understanding diversity

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    This study proposes the Japanese history lesson aiming for promoting deeper understanding diversity because the previous studies in relation to historical inquiry in Japan did not mention about connection with diversity. After conducting the lessons, we found that students mentioned the differences of people’s value between past and present based on the social structure and notions. At the end of study we suggested the reform of history education have more possibilities to develop democratic citizenship
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