Performance Comparisons and Migration Analyses of Lattice-based Cryptosystems on Hardware Security Module

Post-QuantumCryptography(PQC)isregardedasaneffectivewaytoresistattackswithquantum computers. Since National Institute of Standards and Technology (NIST) proposed its PQC standardiza- tion project in 2016, many candidates have been submitted and their quantum-resistant capability has been measuring by researchers. Besides this research, this Migration issues of Post-Quantum Cryptography (PQC) has been attracting more and more at- tentions ever since the National Institute of Standards and Technology (NIST) published round 3 candidates of its PQC standardization project in July, 2020. Many candidates’ quantum-resistant capability had been measured by researchers. Meanwhile, it is also indispensable to point out limitations and give proposals to those candidates’ migration issues, especially for migrating PQC to constrained environments. In this paper, we assume the cases of using PQC on hardware security module (HSM), which is designed to provide a trusted environment to perform cryptographic operations. Our comparisons includes the cases of not only small data (e.g. less than Kilobytes data) which is often used for key encryption or authentication, but also large data (e.g. several Gigabytes data) which is often used for document signing or code signing. We focus on and evaluate hashing and asymmetric operations of three lattice-based cryptosystems which are strong candidates of NIST’s PQC standardization project. Then we construct two kinds of cryptographic bound- aries for those cryptosystems that make their hashing operations inside or outside of a HSM. We compare their performances with several data sizes under different cryptographic boundary constructions, and discuss how much efficiency versus security we gain or lose with internal or external hashing. This problem already exists today with RSA/ECC and our result indicates that it is also acute with the new lattice-based schemes from the NIST round 3 finalists

Correlation between 18F-fluorodeoxyglucose Positron Emission Tomography/computed Tomography and Clinicopathological Features in Invasive Ductal Carcinoma of the Breast

We evaluated the usefulness of preoperative 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) examinations to predict the pathological features in primary breast cancer. In particular, we evaluated the correlation between the maximum standardized uptake values (SUVmax) obtained by 18F-FDG PET/CT and the Ki67 expression in estrogen receptor (ER)-positive invasive ductal carcinoma (IDC). Primary IDC patients operated between March 2009 and July 2013 at Okayama University Hospital were enrolled. We evaluated the correlations between the SUVmax and age, postoperative pT, histological grade, lymph vascular invasion, status of hormone receptor, human epidermal growth factor receptor 2 (HER2), Ki67 expression and node status. The Ki67 expression was classified as high (>14%) versus low (<14%). We enrolled 138 patients with IDC. Their median SUVmax was 3.85 (range:0-52.57). In a univariate analysis, the SUVmax was significantly related to age, pT, histological grade, lymphovascular invasion, hormone receptor status, HER2 status, node status and Ki67. In the 113 patients with ER-positive IDC, there was a significant correlation between Ki67 and SUVmax (p=0.0030). The preoperative 18F-FDG PET/CT results of IDC patients had significant relationships with pathological status parameters. The determination of the preoperative SUVmax might help classify Luminal A and Luminal B patients among luminal-type breast cancer patients

Evaluation of a one-step nucleic acid amplification (OSNA) assay for sentinel lymph node metastases in early breast cancer

　Introduction: The one-step nucleic acid amplification (OSNA) assay is a new method to detect sentinel lymph node (SLN) metastases using cytokeratin 19 (CK19) mRNA in early breast cancer. Here we retrospectively analyzed the advantages and disadvantages of the OSNA assay. 　Methods: In a trial period, SLNs were divided into two sections, and we examined one side using the OSNA assay. The other side was examined by pathologists. After this period, we examined whole SLNs using only the OSNA assay. The patients with positive nodes by OSNA assay and/or pathology required axillary dissection. 　Results: We examined 27 primary breast cancer patients (36 SLNs) during the trial period. The overall concordance rate between the OSNA assay and pathology results was 91%. In the later period, 157 patients (217 SLNs) were examined. The CK19-positive rate obtained by the OSNA assay was 16.5% (macrometastases OSNA (++) : 7.2%, micrometastases OSNA (+) : 9.2%). The non-SLN positive rate among the CK19-positivecases was 23%. The OSNA assay's false negative was one case in which the expression of CK-19 on the primary tumor and lymph node was not detected. 　Conclusions: Our OSNA assay results were comparable to those obtained using a conventional pathological technique. Pathologists and laboratory technicians could save time and effort by using the OSNA assay when seeking the precise diagnosis during surgery

The start-up of thermophilic anaerobic digestion of municipal solid waste

Thermophilic anaerobic digestion of municipal solid wastes (MSW) was conducted for 6 weeks in a lab-scale semi-continuous digester for investigating the start-up operation of anaerobic digestion treating MSW. The feedstock was a mixture of simulated food waste, paper waste, and in some cases, cow manure. Organic loading rate (OLR) was adjusted 1.14 ～ 4.00 gVS/kg-sludge/day to biogas production. At the initial stage of thermophilic anaerobic digestion, pH value gradually increased from 8.2 to 8.3 on 17th day from start-up. Free-ammonia concentration in the digester also gradually increased from 361.6 to 412.5 ppm. On 17th day, inhibition of free-ammonia occurs, and biogas generation stopped. After gas generation stopped on day 17, pH and free-ammonia concentration were adjusted to the proper level by adding paper and deionized water. As a result, gas generation restarted on day 21. Then the amount of food waste charged in the digester was decreased and that of paper waste was increased to adjust the total amount of nitrogen invested in the digester. Afterwards, pH value was settled around 7.8, and a stable digestion was achieved till the end of experiment. Inhibition of free-ammonia could be suppressed by adjusting the amount of nitrogen invested in the digester.都市ごみ（MSW）の高温嫌気性消化発酵（メタン発酵）立ち上げ時の実験条件を調べるために，半連続発酵方法を用いて６週間（１期：１～20日，２期：21～46日）メタン発酵が行われた。生ごみ，紙ごみ，そして牛ふん（立ち上げ時）を混合して発酵原料として供試した。有機物負荷量を，1.14～4.00 VS（有機物濃度）/kg-sludge/dayに調製した。高温（52℃）メタン発酵の初期段階（実験開始から17日目）で，発酵液のpHは8.2から8.3に増加し，遊離アンモニア阻害が生じ，バイオガス生成は停止した。17日目以降，紙ごみとイオン交換水を用いて発酵液のpHと遊離アンモニア濃度を適性値に調整した。その結果， 21日目以降，ガス生成が再び始まった。発酵液の全窒素濃度を調整するために，生ごみ量を減らし，紙ごみ量を増やして原料を供給して発酵試験を進めた。pHは7.8付近を推移，試験終了まで安定的に発酵が行われた。遊離アンモニアによる阻害は，発酵液における窒素量を制御することにより抑えられると考えられる

A&amp;4370, a New Gastrokinetic Agent, Enhances Upper Gastrointestinal Motor Activity in Conscious Dogs

ABSTRACT The effects o