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Shear band evolution and acoustic emission characteristics of sandstone containing non-persistent flaws

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 497-513页

作者： Shuting Miao Peng-zhi pan Chuanqing Zhang Lei Huo State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China CASIC Research Institute of Intelligent Decision Engineering Wuhan430040China

Direct shear tests were conducted on sandstone specimens under different constant normal stresses to study the coalescence of cracks between non-persistent flaws and the shear sliding characteristics of the shear-formed fault.Digital image correlation and acoustic emission(AE)techniques were used to monitor the evolution of shear bands at the rock bridge area and microcracking behaviors.The experimental results revealed that the shear stresses corresponding to the peak and sub-peak in the stressdisplacement curve are significantly affected by the normal stress.Strain localization bands emerged at both the tip of joints and the rock bridge,and their extension and interaction near the peak stress caused a surge in the AE hit rate and a significant decrease in the AE b value.Short and curvilinear strain bands were detected at low normal stress,while high normal stress generally led to more microcracking events and longer coplanar cracks at the rock bridge area.Furthermore,an increase in normal stress resulted in a higher AE count rate and more energetic AE events during friction sliding along the shearformed fault.It was observed that the elastic energy released during the crack coalescence at the prepeak stage was much greater than that released during friction sliding at the post-peak stage.More than 75%of AE events were located in the low-frequency band(0e100 kHz),and this proportion continued to rise with increasing normal stress.Moreover,more AE events of low AF value and high RA value were observed in specimens subjected to high normal stress,indicating that greater normal stress led to more microcracks of shear nature.

关键词： Shear band evolution Acoustic emission(AE) Crack coalescence Normal stress Shear sliding

Uncovering of the formation of rare earth texture and pseudo fiber bimodal microstructure in the high ductility Mg-2Gd-0.4Zr alloy during extrusion

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Journal of Materials Science & Technology 2024年第5期172卷 166-184页

作者： Tianxu Zheng Yaobo Hu chao Zhang Tianshuo Zhao Bin Jiang Fusheng pan Aitao Tang College of Materials Science and Engineering Chongqing UniversityChongqing400044China National Engineering Research Center for Magnesium Alloys Chongqing400044China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai200240China

The aim of this research was to elucidate the underlying mechanism involved in the formation of rare earth(RE)texture and pseudo fiber bimodal microstructure in the high ductility Mg-2Gd-0.4Zr alloy.The microstructure and texture evolution during the extrusion process were analyzed using various tech-niques,including optical microscopy(OM),scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),and electron probe microanalysis(EPMA).The findings revealed that the RE texture in the extruded Mg-2Gd-0.4Zr alloy emerged during the dynamic recrystallization(DRX)process and was further strengthened during the subsequent static recrystallization and grain growth processes.The nu-cleation and growth of grains in the streamline region of Zr particles were delayed in comparison to other regions due to the pinning effect of Zr particles,ultimately resulting in the formation of pseudofiber bi-modal microstructure in the extruded Mg-2Gd-0.4Zr alloy.

关键词： Magnesium alloys Ductility Rare earth texture Bimodal microstructure

METTL9-catalyzed histidine methylation of S100A9 suppresses the anti-Staphylococcus aureus activity of neutrophils

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Protein & Cell 2024年第3期15卷 223-229页

作者： Dan Cao Mengyue Lv Chi Hu Shukai Li Siwen Wang chao Xu Wen pan Department of Digestive Disease The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technologyof ChinaHefei230001China Division of Life Sciences and Medicine The CAS Key Laboratory of Innate Immunity and Chronic DiseaseSchool of Basic Medical SciencesInstitute of ImmunologyUniversity of Science and Technology of ChinaHefei 230027China Division of Life Sciences and Medicine MOE Key Laboratory for Cellular DynamicsHefei National Center for Cross-Disciplinary SciencesUniversity of Science and Technology of ChinaHefei 230027China

Dear Editor,Protein histidine methylation has been found to be a widespread post-translational modification(PTM)in mammalian cells and represents more than 13%of all protein methylation events in the human methylome(Ning et al.,2016;Kapell and Jakobsson,2021).Recently,we and other groups independently identified METTL9 as the first broad-specificity histidine N1 methyltransferase in mammals(Davydova et al.,2021;Lv et al.,2021).METTL9 methylates a variety of substrates with a common x-His-x-His motif(His is for histidine;the second x is preferably small amino acids:A/C/G/S)and catalyzes methyl transfer to the last histidine.

关键词： S100A9 specificity

Long-Term Performance and Microstructural Characterization of Dam Concrete in the Three Gorges Project

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Engineering 2024年第2期33卷 237-262页

作者： Chen Lyu Cheng Yu chao Lu Li pan Wenwei Li Jiaping Liu School of Materials Science and Engineering Southeast UniversityNanjing 211189China State Key Laboratory of High Performance Civil Engineering Materials Sobute New Materials Co.Ltd.Nanjing 211103China China Three Gorges Corporation Wuhan 430010China

This study investigates the long-term performance of laboratory dam concrete in different curing environments over ten years and the microstructure of 17-year-old laboratory concrete and actual concrete cores drilled from the Three Gorges Dam.The mechanical properties of the laboratory dam concrete,whether cured in natural or standard environments,continued to improve over time.Furthermore,the laboratory dam concrete exhibited good resistance to diffusion and a refined microstructure after 17 years.However,curing and long-term exposure to the local natural environment reduced the frost resistance.Microstructural analyses of the laboratory concrete samples demonstrated that moderate-heat cement and fine fly ash(FA)particles were almost fully hydrated to form compact micro structures consisting of large quantities of homogeneous calcium(alumino)silicate hydrate(C-(A)-S-H)gels and a few crystals.No obvious interfacial transition zones were observed in the microstructure owing to the longterm pozzolanic reaction.This dense and homogenous microstructure was the crucial reason for the excellent long-term performance of the dam concrete.A high FA volume also played a significant role in the microstructural densification and performance growth of dam concrete at a later age.The concrete drilled from the dam surface exhibited a loose microstructure with higher microporosity,indicating that concrete directly exposed to the actual service environment suffered degradation caused by water and wind attacks.In this study,both macro-performance and microstructural analyses revealed that the application of moderate-heat cement and FA resulted in a dense and homogenous microstructure,which ensured the excellent long-term performance of concrete from the Three Gorges Dam after 17 years.Long-term exposure to an actual service environment may lead to microstructural degradation of the concrete surface.Therefore,the retained long-term dam concrete samples need to be further researched to better understand its microstructural evolution

关键词： Three Gorges Dam Long-term performance Microstructural analysis Moderate-heat cement Fly ash

Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-Ru Wang Bao-zhi pan Yu-Hang Guo Qing-Hui Wang Yao Guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir evaluation.However,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably difficult.At the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous formations.To overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous rocks.Specifically,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric model.Then we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and porosity.However,it is always difficult to determine the elemental eigenvalues of different minerals in inversion.This paper uses multiple linear regression methods to solve this problem.Finally,an integrated inversion technique for altered igneous formations was developed.The results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray diffraction.The results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formations.

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

Robust Information Hiding Based on Neural Style Transfer with Artificial Intelligence

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Computers, Materials & Continua 2024年第5期79卷 1925-1938页

作者： Xiong Zhang Minqing Zhang Xu AnWang Wen Jiang chao Jiang pan Yang College of Cryptography Engineering Engineering University of People’s Armed PoliceXi’an710086China Key Laboratory of People’s Armed Police for Cryptology and Information Security Xi’an710086China Key Laboratory of CTC&Information Engineering(Engineering University of People’s Armed Police) Ministry of EducationXi’an710086China Staff Department of People’s Armed Police Ningxia Corps Yinchuan750000China

This paper proposes an artificial intelligence-based robust information hiding algorithm to address the issue of confidential information being susceptible to noise attacks during transmission.The algorithm we designed aims to mitigate the impact of various noise attacks on the integrity of secret information during transmission.The method we propose involves encoding secret images into stylized encrypted images and applies adversarial transfer to both the style and content features of the original and embedded data.This process effectively enhances the concealment and imperceptibility of confidential information,thereby improving the security of such information during transmission and reducing security risks.Furthermore,we have designed a specialized attack layer to simulate real-world attacks and common noise scenarios encountered in practical environments.Through adversarial training,the algorithm is strengthened to enhance its resilience against attacks and overall robustness,ensuring better protection against potential threats.Experimental results demonstrate that our proposed algorithm successfully enhances the concealment and unknowability of secret information while maintaining embedding capacity.Additionally,it ensures the quality and fidelity of the stego image.The method we propose not only improves the security and robustness of information hiding technology but also holds practical application value in protecting sensitive data and ensuring the invisibility of confidential information.

关键词： Information hiding neural style transfer robustness

Role of savolitinib in advanced gastric adenocarcinoma with meningeal carcinomatosis and cerebellar metastasis:A case report

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World Journal of Clinical Cases 2024年第15期12卷 2636-2641页

作者： zhi-Yun Weng Wen-Ye Huang Bin-Kan Shi Jian-Jia pan Department of Hematology The Affiliated Yueqing Hospital of Wenzhou Medical UniversityYueqing 325600Zhejiang ProvinceChina

BACKGROUND Brain metastases(BM)are very rare in gastric adenocarcinoma(GaC),and patients with BMs have a higher mortality rate due to stronger tumor aggressiveness.However,its pathogenesis remains unclear.Genetic testing revealed cellular-mesenchymal epithelial transition factor receptor(MET)amplification.Therefore,treatment with savolitinib,a small molecule inhibitor of c-Met,was selected.CASE SUMMARY A 66-year-old woman was diagnosed with advanced GaC 6 months prior to presentation due to back pain.Cerebellar and meningeal metastases were observed during candonilimab combined with oxaliplatin and capecitabine therapy.The patient experienced frequent generalized seizures and persistent drowsiness in the emergency department.Genetic testing of cerebrospinal fluid and peripheral blood revealed increased MET amplification.After discussing treatment options with the patient,savolitinib tablets were administered.After a month of treatment,the intracranial lesions shrank considerably.CONCLUSION BM is very rare in advanced GaC,especially in meningeal cancer,that is characterized by rapid disease deterioration.There are very few effective treatment options available;however,technological breakthroughs in genomics have provided a basis for personalized treatment.Furthermore,MET amplification may be a key driver of BM in gastric cancer;however,this conclusion requires further investigation.

关键词： Cellular-mesenchymal epithelial transition factor receptor Savolitinib Meningeal carcinomatosis Gastric adenocarcinoma Case report

Identification of two compound heterozygous GNRHR mutations in two siblings with congenital hypogonadotropic hypogonadism

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Asian Journal of Andrology 2024年第1期26卷 120-122页

作者： Xiao-Bin Wang Ping Chen Xue-Er Yu Zu-Liang Yao Ting-chao Guo Bo-Chen pan Center for Reproductive Medicine Department of Obstetrics and GynecologyShengjing Hospital of China Medical UniversityShenyang 110004China NuProbe Shanghai 200433China Urology Surgery of The Affiliated Reproductive Hospital of China Medical University and Liaoning Key Laboratory of Reproductive Health Liaoning Research Institute of Family Planning(The Affiliated Reproductive Hospital of China Medical University)Shenyang 110031China NHC Key Laboratory of Reproductive Health and Medical Genetics China Medical UniversityShenyang 110122China

DearEditor,Congenital hypogonadotropic hypogonadism(CHH)is a rare genetic disease characterized by gonadotropin-releasing hormone(GnRH)deficiency or insufficiency and normal hypothalamic-pituitary structures,resulting in defective sexual maturation or/and infertility.!CHH presents as a variety of nonreproductive phenotypes,such as renal hypoplasia,dental hypoplasia,or oculomotor abnormalities.

关键词： pogon compound ism

Preparation of vanadium-based electrode materials and their research progress in solid-state flexible supercapacitors

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Rare Metals 2024年第2期43卷 431-454页

作者： Rui-Jie Zhu Jiang Liu chao Hua Hao-Yu pan Yi-Jun Cao Meng Li Zhongyuan Critical Metals Laboratory Zhengzhou UniversityZhengzhou450001China School of Chemical Engineering Zhengzhou UniversityZhengzhou450001China

Solid-state flexible supercapacitors(SCs)have many advantages of high specific capacitance,excellent flexibility,fast charging and discharging,high power density,environmental friendliness,high safety,light weight,ductility,and long cycle stability.They are the ideal choice for the development of flexible energy storage technology in the future,and provide a good prospect for energy storage applications.At present,solid-state flexible SCs are widely used for portable electronic equipment and wearable energy storage equipment,the research of them has become the focus of a growing number of researchers.Electrode material is the key part of SCs and always determines the electrochemical performance of SCs.It has been a hotspot and focus of research.Vanadium-based compounds are considered to be a promising electrode material for SCs because of variable valence,open structure,high theoretical capacity,and low price.Therefore,this study first gives an overview of solid-state flexible SCs,then reviews the current research status of vanadium-based electrode materials in solid-state flexible SCs,and proposes some strategies to solve some problems of vanadium-based electrode materials.

关键词： Vanadium-based materials Flexible energy storage Specific capacitance Supercapacitors(SCs)