Meet-in-the-Middle Preimage Attacks on Sponge-based Hashing

The Meet-in-the-Middle (MitM) attack has been widely applied to preimage attacks on Merkle-Damg{\aa}rd (MD) hashing. In this paper, we introduce a generic framework of the MitM attack on sponge-based hashing. We find certain bit conditions can significantly reduce the diffusion of the unknown bits and lead to longer MitM characteristics. To find good or optimal configurations of MitM attacks, e.g., the bit conditions, the neutral sets, and the matching points, we introduce the bit-level MILP-based automatic tools on Keccak, Ascon and Xoodyak. To reduce the scale of bit-level models and make them solvable in reasonable time, a series of properties of the targeted hashing are considered in the modelling, such as the linear structure and CP-kernel for Keccak, the Boolean expression of Sbox for Ascon. Finally, we give an improved 4-round preimage attack on Keccak-512/SHA3, and break a nearly 10 years’ cryptanalysis record. We also give the first preimage attacks on 3-/4-round Ascon-XOF and 3-round Xoodyak-XOF

The effects of moisture on microorganisms, quality, and flavor of Liuyang douchi during the pile fermentation period

Objective: Pile fermentation is an important process for the formation of Liuyang Douchi flavor, the initial moisture of the douchi qu during pile fermentation could induce the temperature changes which might further affected the microbial community and flavor compounds formation. Methods: In this paper, metagenomic sequencing, combined with headspace solid-phase microextraction-gas chromatography-mass spectrometry （HS-SPME-GC-MS）, was used to investigate the effects of different moisture （low 35%, medium 42%, high 50%） of the douchi qu on the bacterial community changes and volatile composition of Liuyang Douchi during pile fermentation. Results: The results showed that bacteria in high moisture douchi qu proliferated faster due to the lower center temperature. In detail, the relative abundance of Corynebacterium during the first and second stages of pile-fermentation was positively correlated with pile fermentation moisture, while Staphylococcus during the first stage of pile-fermentation was negatively correlated with pile fermentation moisture; Staphylococcus and Pediococcus during the second stage of pile-fermentation were also negatively correlated with pile fermentation moisture. For volatile compounds, the Douchi pile-fermented with medium moisture had the richest variety of volatile substances, especially pyrazine, but the content of aldehydes and acids were lower. Further correlation analysis showed that Staphylococcus had the greatest impact on differential volatile substances and was significantly positively correlated with six differential volatile substances such as 2,3,5-trimethylpyrazine and 2-ethyl-3,5,6 -Trimethylpyrazine, guaiacol, etc. are significantly positively correlated, followed by Oceanobacillus which was significantly positively correlated with five differential volatile substances. Conclusion: The moisture content of pile fermentation affects the quality of Liuyang Douchi by altering bacterial diversity

Mind the TWEAKEY Schedule: Cryptanalysis on SKINNYe-64-256

Designing symmetric ciphers for particular applications becomes a hot topic. At EUROCRYPT 2020, Naito, Sasaki and Sugawara invented the threshold implementation friendly cipher SKINNYe-64-256 to meet the requirement of the authenticated encryption PFB_Plus. Soon, Thomas Peyrin pointed out that SKINNYe-64-256 may lose the security expectation due the new tweakey schedule. Although the security issue of SKINNYe-64-256 is still unclear, Naito et al. decided to introduce SKINNYe-64-256 v2 as a response. In this paper, we give a formal cryptanalysis on the new tweakey schedule of SKINNYe-64-256 and discover unexpected differential cancellations in the tweakey schedule. For example, we find the number of cancellations can be up to 8 within 30 consecutive rounds, which is significantly larger than the expected 3 cancellations. Moreover, we take our new discoveries into rectangle, MITM and impossible differential attacks, and adapt the corresponding automatic tools with new constraints from our discoveries. Finally, we find a 41-round related-tweakey rectangle attack on SKINNYe-64-256 and leave a security margin of 3 rounds only. As STK accepts arbitrary tweakey size, but SKINNY and SKINNYe-64-256 v2 only support up to 4n tweakey size. We introduce a new design of tweakey schedule for SKINNY-64 to further extend the supported tweakey size. We give a formal proof that our new tweakey schedule inherits the security requirement of STK and SKINNY. We also discuss possible ways to extend the tweakey size for SKINNY-128

Non-targeted Metabolomics Analysis of Metabolic Differences among Liuyang Douchi Fermented by Different Strains

In order to investigate the metabolic differences among Liuyang Douchi fermented by different starter cultures, the contents of total acid and amino nitrogen in Douchi fermented naturally and by using Aspergillus flavus 7214 (AF 7214), A. flavus 7622 (AF 7622), their mixture (AF 7214 + AF 7622) or A. orzyae were determined, and the difference in metabolites among these fermentation strategies was explored by liquid chromatography-mass spectrometry (LC-MS). The results showed that among the five Douchi samples, Douchi fermented by AF 7214 had the highest contents of total acid (3.52%) and amino nitrogen (1.47 g/100 g). The results of partial least squares discriminant analysis (PLS-DA) indicated that significant differences in metabolites were observed among the Douchi samples, and the composition of metabolites in Douchi fermented by AF 7622 showed the smallest difference from that in naturally fermented Douchi. Further analysis revealed that the differential metabolites between Douchi fermented naturally and by using starter cultures were mainly involved in amino acid metabolic pathways, especially arginine biosynthesis. A total of 62 key differential metabolites among the five samples were identified using variable importance in the projection (VIP) greater than 1.5 and P < 0.05 as criteria, including 26 amino acids and their derivatives such as L-lysine, L-serine and 2-methylserine, which indicated that enhanced fermentation showed the most notable influence on the metabolism of amino acids. This study has provided a new understanding of the formation of metabolites during the enhanced fermentation of Liuyang Douchi

A new score system for predicting response to cardiac resynchronization therapy

Background: The aim of this study was to establish a score system derived from clinical, echocardiographic and electrocardiographic indexes and evaluate its clinical value for cardiac resynchronization therapy (CRT) patient selection. Methods: Ninety-three patients receiving CRT were enrolled. A patient selection score system was generated by the clinical, echocardiographic and electrocardiographic parameters achieving a significant level by univariate and multivariate Cox regression model. The positive response to CRT was a left ventricular end systolic volume decrease of ≥ 15% and not reaching primary clinical endpoint (death or re-hospitalization for heart failure) at the end of follow-up. Results: Thirty-nine patients were CRT non-responders (41.94%) and 54 were responders (58.06%). A 4-point score system was generated based on tricuspid annular plane systolic ex­cursion (TAPSE), longitudinal strain (LS), and complete left bundle branch block (CLBBB) combined with a wide QRS duration (QRSd). The sensitivity and specificity for prediction of a positive response to CRT at a score &gt; 2 were 0.823 and 0.850, respectively (AUC: 0.92295% CI 0.691–0.916, p&lt; 0.001). Conclusions: A patient selection score system based on the integration of TAPSE, LS and CLBBB combined with a wide QRSd can help to predict positive response to CRT effectively and reliably

Unsupervisedly Prompting AlphaFold2 for Few-Shot Learning of Accurate Folding Landscape and Protein Structure Prediction

Data-driven predictive methods which can efficiently and accurately transform protein sequences into biologically active structures are highly valuable for scientific research and medical development. Determining accurate folding landscape using co-evolutionary information is fundamental to the success of modern protein structure prediction methods. As the state of the art, AlphaFold2 has dramatically raised the accuracy without performing explicit co-evolutionary analysis. Nevertheless, its performance still shows strong dependence on available sequence homologs. Based on the interrogation on the cause of such dependence, we presented EvoGen, a meta generative model, to remedy the underperformance of AlphaFold2 for poor MSA targets. By prompting the model with calibrated or virtually generated homologue sequences, EvoGen helps AlphaFold2 fold accurately in low-data regime and even achieve encouraging performance with single-sequence predictions. Being able to make accurate predictions with few-shot MSA not only generalizes AlphaFold2 better for orphan sequences, but also democratizes its use for high-throughput applications. Besides, EvoGen combined with AlphaFold2 yields a probabilistic structure generation method which could explore alternative conformations of protein sequences, and the task-aware differentiable algorithm for sequence generation will benefit other related tasks including protein design.Comment: version 2.0; 28 pages, 6 figure

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

Evaluation of analytical and numerical models for the elastic-plastic response of particulate composites

The deformation and failure mechanisms of particle and whisker reinforced metal-matrix composites include inclusion/matrix debonding, ductile failure of the matrix and inclusion cracking. These mechanisms are influenced by processing induced microstructural features such as the inclusion aspect ratio, inclusion orientation distribution, spatial distribution of inclusions (clustering) and residual stresses. To understand the effects of these localized microstructural features on the composite response requires detailed numerical modeling. Numerous modeling techniques have been proposed for the elastic and elastic-plastic response of composites with discontinuous particle and whisker reinforcements. These models are primarily analytical and typically assume idealized microstructural features. Modeling of non-ideal, localized effects requires the development of appropriate numerical procedures. It is therefore of interest to review and compare existing idealized models in order to identify appropriate numerical models to investigate localized effects. In this paper, the composite elastic and elastic-plastic responses predicted by several models are evaluated and discussed. These results may be used to define appropriate numerical models to determine the effects of processing induced microstructural features on the macroscopic composite response