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Success Probability in χ 2-Attacks [chapter]

Takashi Matsunaka, Atsuko Miyaji, Yuuki Takano
2004 Lecture Notes in Computer Science  
Knudsen and Meier applied the χ 2 -attack to RC6. This attack is one of the most effective attacks for RC6. The χ 2 -attack can be used for both distinguishing attacks and for key recovery attacks. Up to the present, theoretical analysis of χ 2 -attacks, especially the relation between a distinguishing attack and a key recovery attack, has not been discussed. In this paper, we investigate the theoretical relation between the distinguishing attack and the key recovery attack for the first time,
more » ... nd prove the theorem to evaluate the success probability of a key recovery attack by using the results of a distinguishing attack. We also demonstrate the accuracy to χ 2 -attack on RC5-64 and RC6 without post-whitening by comparing the implemented results. Keywords RC6, RC5-64, χ 2 attack, statistical analysis 1. A1 = A0; B1 = B0 + S0; C1 = C0; D1 = D0 + S1; 2. for i = 1 to r do: t = F (Bi); u = F (Di); Ai+1 = Bi; 3. Ar+2 = Ar+1 + S2r+2; Br+2 = Br+1; Cr+2 = Cr+1 + S2r+3; Dr+2 = Dr+1.
doi:10.1007/978-3-540-24852-1_23 fatcat:62tyeidgvfgrjhqoy5uacv6bdi

FARIS: Fast and Memory-Efficient URL Filter on CPU and GPGPU

Yuuki Takano, Ryosuke Miura
2017 Software Networking  
Takano received B.E. from National Institution for Academic Degrees and Quality Enhancement of Higher Education, Japan, in 2003.  ... 
doi:10.13052/jsn2445-9739.2017.006 fatcat:qyefzottwfhgth7gjasli277ha

On the Success Probability of χ 2-attack on RC6 [chapter]

Atsuko Miyaji, Yuuki Takano
2005 Lecture Notes in Computer Science  
Knudsen and Meier applied the χ 2 -attack to RC6. The χ 2 -attack can be used for both distinguishing attacks and key recovery attacks. Up to the present, the success probability of key recovery attack in any χ 2attack has not been evaluated theoretically without any assumption of experimental results. In this paper, we discuss the success probability of key recovery attack in χ 2 -attack and give the theorem that evaluates the success probability of a key recovery attack without any assumption
more » ... of experimental approximation, for the first time. We make sure the accuracy of our theorem by demonstrating it on both 4-round RC6 without post-whitening and 4-round RC6-8. We also evaluate the security of RC6 theoretically and show that a variant of the χ 2 -attack is faster than an exhaustive key search for the 192-bit-key and 256-bit-key RC6 with up to 16 rounds. As a result, we succeed in answering such an open question that a variant of the χ 2 -attack can be used to attack RC6 with 16 or more rounds.
doi:10.1007/11506157_6 fatcat:bxcexhplo5bx7bri6lgjfdtely

FARIS: Fast and Memory-Efficient URL Filter on CPU and GPGPU

Yuuki Takano, Ryosuke Miura
2017 Convergence Security  
Takano received B.E. from National Institution for Academic Degrees and Quality Enhancement of Higher Education, Japan, in 2003.  ... 
doi:10.13052/jcs2445-9992.2017.002 fatcat:ixpint4lybc3ddgcofzth2uo7q

Secure Primitive for Big Data Utilization [chapter]

Akinori Kawachi, Atsuko Miyaji, Kazuhisa Nakasho, Yiying Qi, Yuuki Takano
2020 Security Infrastructure Technology for Integrated Utilization of Big Data  
In this chapter, we describe two security primitives for big data utilization. One is a privacy-preserving data integration among databases distributed in different organizations. This primitive integrates the same data among databases kept in different organizations while keeping any different data in an organization secret to other organizations. Another is a privacy-preserving classification. This primitive executes a procedure for server's classification rule to client's input database and
more » ... utputs only the result to the client while keeping the client's input database secret to the server and server's classification rule to the client. These primitives can be executed not only independently but also jointly. That is, after we integrate databases from distributed organization by executing the privacy-preserving data integration, we can execute a privacy-preserving classification.
doi:10.1007/978-981-15-3654-0_3 fatcat:b5e2addf6vblhnrtxt4fw3cly4

Surface Evolution of GaP Grown on Si Substrates Using Metalorganic Vapor Phase Epitaxy

Yasushi Takano, Tatsuya Takagi, Yuuki Matsuo, Shunro Fuke
2010 Japanese Journal of Applied Physics  
GaP surface evolution on Si substrates in the initial growth stage was investigated using atomic force microscopy. The GaP was grown on 4°-misoriented Si substrates at 700-830°C using metalorganic vapor phase epitaxy. Island growth was predominant below nominal 5-nm thickness at 830°C. Several antiphase domains (APDs) grew to be 100 nm or longer at nominal 5 nm deposition. They were 5 nm higher than surrounding islands. The surrounding islands formed a layer at a nominal thickness over 5 nm.
more » ... layer grew vertically faster than the APDs. Several APDs grew laterally until a layer-thickness exceeded an APD height. The layer finally embedded the APDs. Self-annihilation of APDs was achieved below 40-nm thickness. Similar surface evolution was found at 770 and 800°C. The APD size decreased with decreasing temperature. Self-annihilation of APDs was achieved below 20-nm thickness at 770°C.
doi:10.1143/jjap.49.035502 fatcat:ll2xnbc4nvd23hdnah3ugja6cu

Towards an Interactive Experiment Framework: DynamiQ

Razvan Beuran, Shingo Yasuda, Tomoya Inoue, Yuuki Takano, Toshiyuki Miyachi, Yoichi Shinoda
2015 Proceedings of the 10th EAI International Conference on Testbeds and Research Infrastructures for the Development of Networks & Communities  
Interactive network experiments are useful for finding solutions to network problems, for teaching and for training purposes. In this demonstration we shall present an interactive experiment framework that allows users to directly control the experiment scenario by using a touch panel interface. This framework uses the network emulation module named dynamiQ for the dynamic emulation of networks. The demonstration uses a scenario with up to 55 emulated nodes, out of which 30 nodes form an
more » ... d vehicular network and 5 are static buildings. The other nodes represent wireless towers and unmanned aerial vehicles that can be freely placed in the virtual experiment area. Participants are tasked with creating a multi-hop mesh network for sending video tra c between two predefined remote locations. A similar demonstration has already been shown at Interop Tokyo 2014, where it received a special jury award.
doi:10.4108/icst.tridentcom.2015.259857 dblp:journals/eetcs/BeuranYITMS15 fatcat:efdresynmndzpmw4mxlx3tp5jy

Histochemical fluorescent staining of Sendai virus-infected cells with a novel sialidase substrate

Maiko Takano, Tadanobu Takahashi, Takashi Agarikuchi, Yuuki Kurebayashi, Akira Minami, Tadamune Otsubo, Kiyoshi Ikeda, Hiroaki Kanazawa, Takashi Suzuki
2014 Virology  
Sialidases, enzymes that remove terminal sialic acid residues, are pivotal in various biological processes such as malignancy and infection with pathogens. For histochemical staining of sialidase activity, we have developed a new synthetic sialidase substrate, sialic acid-conjugated fluorescent benzothiazolylphenol derivative (BTP3-Neu5Ac), for rapid, sensitive, and specific fluorescent staining of sialidase activity. Here, we showed the usefulness of BTP3-Neu5Ac for histochemical fluorescent
more » ... aining of cells infected with Sendai virus (SV), which possesses sialidase activity. BTP3-Neu5Ac also visualised SVinfected regions of lung sections from SV-infected mice. We succeeded in histochemical fluorescent staining of SV both in vitro and in vivo. SV has been utilised in many virological and biotechnological studies such as developments of an oncolytic virus, a gene therapy vector, and a vaccine candidate. BTP3-Neu5Ac should contribute to rapid progress of such studies and researches on viral sialidase.
doi:10.1016/j.virol.2014.04.005 pmid:25090482 fatcat:wgd36uny5rf2bkeonvuif6lbgy

Rapid Fluorescent Detection Assay for Human Parainfluenza Viruses

Tadanobu Takahashi, Maiko Takano, Yuuki Kurebayashi, Takashi Agarikuchi, Chihiro Suzuki, Keijo Fukushima, Shunsaku Takahashi, Tadamune Otsubo, Kiyoshi Ikeda, Akira Minami, Takashi Suzuki
2015 Biological and Pharmaceutical Bulletin  
Human parainfluenza virus type 1 (hPIV1) does not form clear plaque by the conventional plaque formation assay because of slightly a cytopathic effects in many cell lines infected with hPIV1, thus making in virus titration, isolation and inhibitor evaluation difficult. We have succeeded in fluorescent histochemical visualization of sialidase activities of influenza A and B viruses, Newcastle disease virus and Sendai virus by using a novel fluorescent sialidase substrate,
more » ... bromophenyl 5-acetamido-3,5-dideoxyα-D-glycero-D-galacto-2-nonulopyranosidonic acid (BTP3-Neu5Ac). In this study, we applied the BTP3-Neu5Ac assay for rapid detection of hPIV1 and hPIV type 3. The BTP3-Neu5Ac assay could histochemically visualize dot-blotted hPIVs on a membrane and hPIV-infected cells as local fluorescence under UV irradiation. We succeeded in distinct fluorescent visualization of hPIV1-infected cells in only 3 d using the BTP3-Neu5Ac assay. Due to there being no fixation, hPIV1 was isolated directly from fluorescent stained focus cells by the BTP3-Neu5Ac assay. Establishment of a sensitive, easy, and rapid fluorescent focus detection assay for hPIV, hPIV1 in particular will contribute greatly to progress in hPIV studies.
doi:10.1248/bpb.b15-00298 pmid:26235585 fatcat:t4qbwaw6ivgs7c4s42f2g4vjru

Clinical Results and Pump Analysis of the Gyro Pump for Long-Term Extracorporeal Life Support

Takamitsu Terasaki, Tamaki Takano, Yuuki Michinaga, Michihiro Yokokawa, Yuko Wada, Tatsuichirou Seto, Daisuke Fukui, Jun Amano
2013 Artificial Organs  
Rescuing patients in severe cardiac failure with extracorporeal support remains challenging. The Gyro pump is a centrifugal blood pump and now used for cardiopulmonary bypass although it is originally developed for long-term cardiac assist. Little is known about clinical experiences using this pump. We here report the clinical results of long-term extracorporeal life support for over 4 days using the Gyro pump with Excelung, a hollow fiber oxygenator coated with silicone and heparin. Seven
more » ... nts underwent extracorporeal life support with 15 pump and oxygenator combinations. Gyro and Excelung were used for veno-arterial extracorporeal support in 6 patients and for right ventricular support in one patient. Patient characteristics, pump driving conditions and blood chemistry were obtained retrospectively. All pumps were subsequently disassembled and examined macroscopically, with 6 of the 15 pumps also examined by scanning electron microscopy (SEM). The patient mortality rate was 57.1 %. Mean duration of support was 10.5±7.2 days per pump and oxygenator combination. Lactate dehydrogenase and asparate aminotransferase were generally maintained below 1000 and 100 IU/L, respectively, after the first 4 days of pump driving. Thrombi were found in 2 pumps, one used without anti-coagulation and the other driven at very slow rotational speed of 1077. SEM revealed no wear in the male bearings and very low wear and deformation (0.02 ± 0.03mm) in the female bearings. The combination of Gyro and Excelung may be applicable for long-term biventricular and right ventricular support, although proper anticoagulation should be administrated to avoid thrombus formation inside the pump.
doi:10.1111/aor.12171 pmid:24021058 fatcat:ke3u3forrbf3vpey5dllot3u5q

DynamiQ: A Tool for Dynamic Emulation of Networks

Razvan Beuran, Shingo Yasuda, Tomoya Inoue, Yuuki Takano, Toshiyuki Miyachi, Yoichi Shinoda
2015 Proceedings of the 10th EAI International Conference on Testbeds and Research Infrastructures for the Development of Networks & Communities  
Interactive network experiments, in which experiment conditions change dynamically based on input from users or other external sources, are the most appropriate approach when evaluating solutions to practical network problems, for teaching and/or training purposes, etc. Support for dynamic experiment conditions is also required whenever an experiment cannot be fully defined from start, for instance when node behavior (application execution, mobility pattern, etc.) depends on factors such as
more » ... unication conditions in the experiment, traffic content, and so on. In this paper we present the network emulation module named dynamiQ that makes possible the dynamic emulation of networks. We also outline an interactive experiment framework that uses dynamiQ to meet the above requirements. The evaluation of dynamiQ in this context shows that no significant performance penalties occur because of its dynamic nature. Our interactive experiment framework has already been used in practice, including for a demonstration at Interop Tokyo 2014.
doi:10.4108/icst.tridentcom.2015.259856 dblp:journals/sas/BeuranYITMS15 fatcat:ncugzoiztnfqdgbzyc3tbk3tv4

Angiotensin-Converting Enzyme Inhibitor Therapy Inhibits the Progression From Paroxysmal Atrial Fibrillation to Chronic Atrial Fibrillation

Yoshiyuki Hirayama, Hirotsugu Atarashi, Yoshinori Kobayashi, Tsutomu Horie, Yuuki Iwasaki, Mitsunori Maruyama, Yasushi Miyauchi, Toshihiko Ohara, Masaaki Yashima, Teruo Takano
2005 Circulation Journal  
doi:10.1253/circj.69.671 pmid:15914944 fatcat:gew5iddasfbozhmxsxfu7z42jm

Examination of prognostic factors in patients undergoing surgery for colorectal perforation: A case controlled study

Tetsuo Sumi, Kenji Katsumata, So Katayanagi, Yuuki Nakamura, Tomohisa Nomura, Kiminori Takano, Kazuhiko Kasuya, Motohide Shimazu, Akihiko Tsuchida
2014 International Journal of Surgery  
Objective: To determine if the POSSUM, SOFA, MPI, and SAS scores provide a better measure of severity for patients with prognostic factors undergoing surgery for colorectal perforation. Subjects: Fifty-nine patients who underwent surgery between 1996 and 2012. Methods: We retrospectively reviewed background factors, blood and physiological test results, and intraoperative findings of patients who survived and those who died. We also compared the POSSUM, SOFA, MPI, and SAS scores. Multivariate
more » ... alysis was performed for factors that were significant by univariate analysis, and selected factors were used to produce a predictive prognostic model. Results: Univariate analysis revealed significant differences in age, anticoagulant/steroid administration, serum creatinine level, PF ratio, base excess (BE), chest radiography, pulse rate, and severity of peritoneal soiling. Age, serum creatinine level, pulse rate, and severity of peritoneal soiling were selected for multivariate analysis; only pulse rate was significantly different. There were significant differences between the two groups in POSSUM PS, OSS, SOFA, and MPI scores, and a comparison in terms of the ROC curve showed that our model had the highest peak; the area under the curve was 94.8% compared with 70e80% for the other systems, suggesting that our model is better than those systems. Conclusions: POSSUM and SOFA are valid methods of evaluating risk from colorectal perforation, but our study revealed addition risk factors: (1) the PF ratio and BE, which are not included in POSSUM; (2) the pulse rate and severity of peritonitis, which are not included in SOFA; and (3) anticoagulant/steroid hormone administration.
doi:10.1016/j.ijsu.2014.03.021 pmid:24709571 fatcat:vys2nwkd7zgdxaszvtuxwgeofu

Imaging of influenza virus sialidase activity in living cells

Yuuki Kurebayashi, Tadanobu Takahashi, Tadamune Otsubo, Kiyoshi Ikeda, Shunsaku Takahashi, Maiko Takano, Takashi Agarikuchi, Tsubasa Sato, Yukino Matsuda, Akira Minami, Hiroaki Kanazawa, Yuko Uchida (+7 others)
2014 Scientific Reports  
doi:10.1038/srep04877 pmid:24786761 pmcid:PMC4007088 fatcat:wwsvqsokbnctbk5yot4hwzexbi

Study on Suitability of KOD DNA Polymerase for Enzymatic Production of Artificial Nucleic Acids Using Base/Sugar Modified Nucleoside Triphosphates

Masayasu Kuwahara, Yuuki Takano, Yuuya Kasahara, Hiroki Nara, Hiroaki Ozaki, Hiroaki Sawai, Akio Sugiyama, Satoshi Obika
2010 Molecules  
Recently, KOD and its related DNA polymerases have been used for preparing various modified nucleic acids, including not only base-modified nucleic acids, but also sugar-modified ones, such as bridged/locked nucleic acid (BNA/LNA) which would be promising candidates for nucleic acid drugs. However, thus far, reasons for the effectiveness of KOD DNA polymerase for such purposes have not been clearly elucidated. Therefore, using mutated KOD DNA polymerases, we studied here their catalytic
more » ... es upon enzymatic incorporation of nucleotide analogues with base/sugar modifications. Experimental data indicate that their characteristic kinetic properties enabled incorporation of various modified nucleotides. Among those KOD mutants, one achieved efficient successive incorporation of bridged nucleotides with a 2′-ONHCH 2 CH 2 -4′ linkage. In this study, the characteristic kinetic properties of KOD DNA polymerase for modified nucleoside triphosphates were shown, and the effectiveness of genetic engineering in improvement of the enzyme for modified nucleotide polymerization has been demonstrated. OPEN ACCESS Molecules 2010, 15 8230
doi:10.3390/molecules15118229 pmid:21076389 pmcid:PMC6259326 fatcat:fyy75hbkxbgotd5qvbf6zp6e54
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