verifying anonymous credential systems in applied pi calculus

Anonymous credentials are widely used to certify properties of a credential owner or to support the owner to demand valuable services, while hiding the users identity at the same time. A credential system (a.k.a. pseudonym system) usually consists of multiple interactive procedures between users and organizations, including generating pseudonyms, issuing credentials and verifying credentials, which are required to meet various security properties. We propose a general symbolic model (based on the applied pi calculus) for anonymous credential systems and give formal definitions of a few important security properties, including pseudonym and credential unforgeability, credential safety, pseudonym untraceability. We specialize the general formalization and apply it to the verification of a concrete anonymous credential system proposed by Camenisch and Lysyanskaya. The analysis is done automatically with the tool ProVerif and several security properties have been verified. © 2009 Springer-Verlag

High Steep Rock Slope Instability Mechanism Induced by the Pillar Deterioration in the Mountain Mining Area

In hilly regions, landslides or slope failures are very common phenomena, when underground mineral resources are excavated. In this study, some landslide disasters in a mountain mining area were analyzed. The engineering geological and instability reason were investigated. The numerical simulation of a high steep rock slope disturbed by a room and pillar mine was established. The failure process of a high steep rock slope induced by the pillar deterioration was analyzed to reveal the characteristics of deformation and sliding. The results show that the pillar plays an important role in maintaining the stability of the slope, if the pillar can support the overlying rock mass, only a tiny deformation will be induced. When the pillar fails and the roof caves, the overlying rock mass above the room and pillar goaf will rapidly subside, and the crack evolution of slope is induced, forming the potential slip surface. The landslide mass gradually moves. When the rock mass at the middle and lower of the slope is squeezed out, slope sliding will be induced. The failure process can be divided into four stages as follow: tiny displacement is caused by the mining, roof collapse is caused by the pillar failure, the potential slip surface is formed from the crack evolution; the slope sliding is induced by the fracturing of rock mass at the middle and lower of the slope

Research on Locally Resonant Characteristics of Pipelines with Periodic Structure

In this paper, the propagation characteristics of vibration waves in periodic pipelines were studied based on the band theory of phononic crystals, and we analyzed the influence of the geometrical structure parameters on the band gap characteristics of pipelines. The results show that, by increasing the number of layers of local resonant structure, both the initial frequency and the cutoff frequency of the band gap moved towards the lower frequency, while the width of the system band gap increased by 35 Hz, and the damping effect increased by 18.3 dB. By changing the thickness of the wall of the pipeline system, the width of the system band gap increased by 20 Hz, and the damping effect increased by 9.1 dB. The maximum vibration isolation of the offshore platform truss based on the periodic structure can be up to 7.93 dB. Therefore, it is feasible to apply the local resonant periodic structure to the vibration control of a practical offshore platform

Application of Clustering and Stepwise Discriminant Analysis Based on Hydrochemical Characteristics in Determining the Source of Mine Water Inrush

In order to explore the law of groundwater evolution, the water source connection between faults and aquifers and the main sources of mine water inrush in the deep mining area of Yangcheng Coal Mine in Jining City, 40 groups of hydrochemical samples were collected and analyzed by Piper Diagram and Durov Diagram. The results showed that the fluidity of groundwater developing to the deep became weaker, the value of total dissolved solids (TDS) became larger. So, the roof and floor of coal seam were more similar in water quality types due to the conduction of faults. Using principal component analysis (PCA) to the raw data, two principal components were extracted, and the principal component scores were used as clustering variables for hierarchical cluster analysis (HCA), 5 groups of abnormal water samples were eliminated and 3 clustering groups M1, M2 and M3 were obtained from the other water samples on the tree diagram. The results showed that the combination of HCA and hydrochemical analysis was more effective in screening water samples, and the 3 clustering groups could be qualified samples to represent 3 major aquifers (Taiyuan Formation limestone aquifer, Shanxi Formation sandstone aquifer and Ordovician limestone aquifer). Finally, taking M1, M2 and M3 as grouping variables, the discriminant functions f1, f2 and f3 of the 3 aquifers were obtained, the results of stepwise discrimination analysis (SDA) showed that the discrimination model established by using 25 groups of standard water samples could discriminate the known water samples with the correct rate of 96%, 10 groups of unknown water samples collected at the fault are identified as Taiyuan Formation limestone water samples, which was consistent with the classification results of HCA, proving that the water inrush of fault DF53 was from Taiyuan Formation limestone aquifer, while the fault had little influence on Ordovician limestone aquifer

New Cyclic Pentapeptides from the Mangrove-Derived <i>Aspergillus fumigatus</i> GXIMD 03099

Four new cyclic pentapeptides, avellanins D–G (1–4), together with four known compounds (5–8), were isolated from a mangrove-derived Aspergillus fumigatus GXIMD 03099 fungus from Acanthus ilicifolius L. Their structures were elucidated by analysis of HRESIMS, NMR, and ESI-MS/MS data. Their absolute configurations were determined by X-ray diffraction analysis and Marfey’s method. Compounds 1–8 were screened for insecticidal and antibacterial activities. Compound 2 showed insecticidal activity against newly hatched larvae of Culex quinquefasciatus with an LC50 value of 86.6 µM; compound 4 had weak activity against Vibrio harveyi with an MIC value of 5.85 µM

Serotype specific epitopes identified by neutralizing antibodies underpin immunogenic differences in Enterovirus B

So far no vaccine or antiviral therapy is available for Echovirus 30 (E30) that causes aseptic meningitis. Here, the authors generate and characterise two E30-specific monoclonal antibodies that block binding of the virus to its attachment receptor CD55 and uncoating receptor FcRn, and determine the cryo-EM structures of E30 with the bound neutralizing antibodies

Deletion of V483 in the spike confers evolutionary advantage on SARS-CoV-2 for human adaptation and host-range expansion after a prolonged pandemic.

Acknowledgements: We express our gratitude to Drs. Boling Zhu, Xujing Li, and Lihong Chen for their valuable contribution in cryo-EM data collection at the Center for Biological Imaging (CBI) of the Institute of Biophysics. We would like to express our gratitude to Drs. Yuanyuan Chen, Bingxue Zhou, Zhenwei Yang, and Xianjin Ou for providing technical assistance with Surface Plasmon Resonance (SPR). This work was supported by the National Key R&D Program (2023YFC2306000 and 2018YFA0900801), the Ministry of Science and Technology of China (CPL-1233 and SRPG22-003), CAS (YSBR-010) and the National Science Foundation Grants (12034006, 32325004 and T2394482). Xiangxi Wang was supported by the National Science Fund for Distinguished Young Scholar (32325004) and the NSFS Innovative Research Group (81921005).Funder: Work was supported by Ministry of Science and Technology of China (CPL-1233 and SRPG22-003), National Key Research and Development Program (2018YFA0900801), CAS (YSBR-010) and the National Science Foundation Grants (12034006, 32325004 and T2394482). Xiangxi Wang was supported by National Science Fund for Distinguished Young Scholar (No. 32325004) and the NSFS Innovative Research Group (No. 81921005)