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Effects of thawing-induced softening on fracture behaviors of frozen rock

Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 979-989页

作者： Ting Wang Hailiang jia qiang Sun Xianjun Tan Liyun Tang College of Geology and Environment Xi’an University of Science and TechnologyXi’an710054China College of Architecture and Civil Engineering Xi’an University of Science and TechnologyXi’an710054China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430064China

Due to the presence of ice and unfrozen water in pores of frozen rock,the rock fracture behaviors are susceptible to temperature.In this study,the potential thawing-induced softening effects on the fracture behaviors of frozen rock is evaluated by testing the tension fracture toughness(KIC)of frozen rock at different temperatures(i.e.-20℃,-15℃,-12℃,-10℃,-8℃,-6℃,-4℃,-2℃,and 0℃).Acoustic emission(AE)and digital image correlation(DIC)methods are utilized to analyze the microcrack propagation during fracturing.The melting of pore ice is measured using nuclear magnetic resonance(NMR)method.The results indicate that:(1)The KIC of frozen rock decreases moderately between-20℃ and-4℃,and rapidly between-4℃ and 0℃.(2)At-20℃ to-4℃,the fracturing process,deduced from the DIC results at the notch tip,exhibits three stages:elastic deformation,microcrack propagation and microcrack coalescence.However,at-4℃e0℃,only the latter two stages are observed.(3)At-4℃e0℃,the AE activities during fracturing are less than that at-20℃ to-4℃,while more small events are reported.(4)The NMR results demonstrate a reverse variation trend in pore ice content with increasing temperature,that is,a moderate decrease is followed by a sharp decrease and-4℃ is exactly the critical temperature.Next,we interpret the thawing-induced softening effect by linking the evolution in microscopic structure of frozen rock with its macroscopic fracture behaviors as follow:from-20℃ to-4℃,the thickening of the unfrozen water film diminishes the cementation strength between ice and rock skeleton,leading to the decrease in fracture parameters.From-4℃ to 0℃,the cementation effect of ice almost vanishes,and the filling effect of pore ice is reduced significantly,which facilitates microcrack propagation and thus the easier fracture of frozen rocks.

关键词： Frozen sandstone Different thawing temperature Fracture toughness Microcrack propagation process Unfrozen water content

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Heteroatom anchors Fe-Mn dual-atom catalysts with bi-functional oxygen catalytic activity for low-temperature rechargeable flexible Zn-air batteries

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Journal of Energy Chemistry 2024年第3期90卷 610-620,I0014页

作者： Yuting He Hongtao Li Yi Wang Yufei jia Yongning Liu qiang Tan State Key Laboratory for Mechanical Behaviour of Materials School of Materials Science&EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina

M-N-C(M=Fe,Co,Ni,etc.) catalyst owns high catalytic activity in the oxygen catalytic reaction which is the most likely to replace the Pt-based catalysts.But it is still a challenge to further increase the active site density.This article constructs the high-efficiency FeMn-N/S-C-1000 catalyst to realize ORR/OER bifunctional catalysis by hetero-atom,bimetal(Fe,Mn) doped simultaneously strategy.When evaluated it as bi-functional electro-catalysts,FeMn-N/S-C-1000 exhibits excellent catalytic activity(E_(1/2)=0.924 V,E_(j=10)=1.617 V) in alkaline media,outperforms conventional Pt/C,RuO_(2) and most non-precious-metal catalysts reported recently,Such outstanding performance is owing to N,S co-coordinated with metal to form multi-types of single atom,dual atom active sites to carry out bi-catalysis.Importantly,nitrite poison test provides the proof that the active sites of FeMn-N/S-C are more than that of single-atom catalysts to promote catalytic reactions directly.To better understand the local structure of Fe and Mn active sites,XAS and DFT were employed to reveal that FeMn-N_5/S-C site plays the key role during catalysis.Notably,the FeMn-N/S-C-1000 based low-temperature rechargeable flexible Zn-air also exhibits superior discharge performance and extraordinary durability at-40℃.This work will provide a new idea to design diatomic catalysts applied in low-temperature rechargeable batteries.

关键词： Fe Mn-N/S-C-1000 ORR OER Rechargeable flexible Zn-air batteries

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miR-200b-3p accelerates progression of pituitary adenomas by negatively regulating expression of RECK

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Oncology Research 2024年第5期32卷 933-941页

作者： XIAOXI WANG YANFEI jia qiang LI qiang YANG YINGFENG LIU BEIFENG WEI XIANG NIU YINJIE ZHANG XIAODONG LUO ZIYU ZHAO PENG WANG Department of Neurosurgery Tianshui First People’s HospitalTianshuiChina Department of Neurosurgery The Second Affiliated Hospital of Lanzhou UniversityLanzhouChina

MicroRNA(miR)-200b-3p has been associated with many tumors,but its involvement in pituitary adenoma is unclear.This study investigated the molecular mechanism underlying miR-200b-3p regulation in pituitary adenomas to provide a theoretical basis for treatment.Bioinformatics was used to analyze pituitary adenoma-related genes and screen new targets related to RECK and miRNA.As well,the relationship between miR-200b-3p and RECK protein was verified using a double-luciferase reporter gene assay.The expression of miR-200b-3p in clinical samples was analyzed by in situ hybridization.Transfection of the miR-200b-3p inhibitor and small interfering-RECK(si-RECK)was verified by qPCR.GH3 cell viability and proliferation were detected using CCK8 and EdU assays.Apoptosis was detected by flow cytometry and western blotting.Wound healing and Transwell assays were used to detect cell migration and invasion.The effects of miR-200b-3p and RECK on GH3 cells were verified using salvage experiments.miR-200b-3p was highly expressed in pituitary tumor tissue.Inhibitors of miR-200b-3p inhibited cell proliferation promoted cell apoptosis,inhibited invasion and migration,and inhibited the expression of matrix metalloproteinases.Interestingly,miR-200b-3p negatively regulated RECK.The expression of RECK in pituitary adenoma tissues was lower than that in neighboring tissues.Si-RECK rescued the function of miR-200b-3p inhibitors in the above cellular behaviors,and miR-200b-3p accelerated the development of pituitary adenoma by negatively regulating RECK expression.In summary,this study investigated the molecular mechanism by which miR-200b-3p regulates the progression of pituitary adenoma through the negative regulation of RECK.The findings provide a new target for the treatment of pituitary adenoma.

关键词： Pituitary adenomas miR-200b-3p RECK Matrix metalloproteinase

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Progress in research on metal-based materials in stabilized Zn anodes

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Rare Metals 2024年第1期43卷 20-40页

作者： Le Li Shao-Feng jia Ming-Hui Cao Yong-qiang Ji Heng-Wei Qiu Dan Zhang Shaanxi Key Laboratory of Industrial Automation School of Mechanical EngineeringShaanxi University of TechnologyHanzhong 723001China School of Electronic and Information Engineering Qingdao UniversityQingdao 266071China State Key Laboratory for Artifcial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Department of Chemistry Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical BiologyTsinghua UniversityBeijing 100084China Shaanxi Key Laboratory of Catalysis School of Chemistry and Environment ScienceShaanxi University of TechnologyHanzhong 723001China

Aqueous zinc-ion batteries(ZIBs) combine the benefits of metallic Zn anodes with those of aqueous electrolytes and are well suited for large-scale energy storage because of their inherent high safety, cost-effectiveness, and eco-friendliness. Currently, the practical application of such batteries is hindered by the poor cycling performance of Zn anodes due to uncontrolled dendrite formation and severe side reactions, although recent reports suggest that these problems can be mitigated through the modification of Zn anodes with metal-based materials.Given that the mechanisms of improving Zn deposition and the structural evolution of metal-based materials have not been systematically reviewed, we herein systematically overview the metal-based materials used to stabilize Zn anodes, starting with a brief summary of the anode working mechanism and the challenges faced by stabilized Zn anodes. Subsequently, the design principles of Zn anodes stabilized by metal-based materials and the related recent progress are reviewed, and the key challenges and perspectives for the future development of such Zn anodes are proposed.

关键词： Zinc-ion batteries(ZIBs) Zn anode Metalbased materials Alloying metal Stabilized Zn anodes

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Recent advances in electrocatalytic generation of indole-derived radical cations and their applications in organic synthesis

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Chinese Chemical Letters 2024年第4期35卷 106-123页

作者： Wei Zhou Xi Chen Lin Lu Xian-Rong Song Mu-jia Luo qiang Xiao Key Laboratory of Organic Chemistry of jiangxi Province Jiangxi Science&Technology Normal UniversityNanchang 330013China

Indole-derived radical cations, open-shell reactive species, display distinctive dual reactivity due to the carbon-centered radical and more electrophilic carbocation, which frequently appear in a variety of single electron oxidation reactions for synthesizing structurally diverse functionalized indoles and indolines. Electrocatalysis is considered as a synthetically attractive and environmentally friendly alternative for driving the single electron oxidation of indoles. Remarkable achievements in electrocatalytic indolederived radical cation-mediated indole functionalization have been realized so far. This review comprehensively summarizes the recent progresses in the applications of electrocatalytic indole radical cations,including C(sp~2)–H functionalization, dearomative 2,3-difunctionalization, and ring-opening reaction, emphasizing the vital single electron oxidation steps of indoles, the substrates scope and limitations, and the reaction mechanisms.

关键词： Electrocatalysis Indole radical cation C-H functionalizatin Dearomative 2 3-difunctionalization

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Clinical review and literature analysis of hepatic epithelioid angiomyolipoma in alcoholic cirrhosis: A case report

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World Journal of Clinical Cases 2024年第14期12卷 2382-2388页

作者： Jing-qiang Guo jia-Hui Zhou Kun Zhang Xin-Liang Lv Chao-Yong Tu Department of Hepatobiliary and Pancreatic Surgery Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina Department of Pathology Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina Department of General Surgery The Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKGROUND Hepatic epithelioid angiomyolipoma(HEA)has a low incidence and both clinical manifestations and imaging lack specificity.Thus,it is easy to misdiagnose HEA as other tumors of the liver,especially in the presence of liver diseases such as hepatitis cirrhosis.This article reviewed the diagnosis and treatment of a patient with HEA and alcoholic cirrhosis,and analyzed the literature,in order to improve the understanding of this disease.CASE SUMMARY A 67-year-old male patient with a history of alcoholic cirrhosis was admitted due to the discovery of a space-occupying lesion in the liver.Based on the patient’s history,laboratory examinations,and imaging examinations,a malignant liver tumor was considered and laparoscopic partial hepatectomy was performed.Postoperative pathology showed HEA.During outpatient follow-up,the patient showed no sign of recurrence.CONCLUSION HEA is difficult to make a definite diagnosis before surgery.HEA has the poten-tial for malignant degeneration.If conditions permit,surgical treatment is recom-mended.

关键词： Hepatic epithelioid angiomyolipoma Alcoholic cirrhosis Magnetic resonance imaging Computed tomography Immunohistochemistry Misdiagnose analysis Case report

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Evaluation of genetic response of mesenchymal stem cells to nanosecond pulsed electric fields by whole transcriptome sequencing

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World Journal of Stem Cells 2024年第3期16卷 305-323页

作者： jian-Jing Lin Tong Ning Shi-Cheng jia Ke-jia Li Yong-Can Huang qiang Liu jian-Hao Lin Xin-Tao Zhang Department of Sports Medicine and Rehabilitation Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina Institute of Medical Science The Second HospitalCheeloo College of MedicineShandong UniversityJinan 250033Shandong ProvinceChina Department of Biomedical Engineering Institute of Future TechnologyPeking UniversityBeijing 100871China Shenzhen Engineering Laboratory of Orthopaedic Regenerative Technologies Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina Arthritis Clinical and Research Center Peking University People’s HospitalBeijing 100044China

BACKGROUND Mesenchymal stem cells(MSCs)modulated by various exogenous signals have been applied extensively in regenerative medicine research.Notably,nanosecond pulsed electric fields(nsPEFs),characterized by short duration and high strength,significantly influence cell phenotypes and regulate MSCs differentiation via multiple pathways.Consequently,we used transcriptomics to study changes in messenger RNA(mRNA),long noncoding RNA(lncRNA),microRNA(miRNA),and circular RNA expression during nsPEFs application.AIM To explore gene expression profiles and potential transcriptional regulatory mechanisms in MSCs pretreated with nsPEFs.METHODS The impact of nsPEFs on the MSCs transcriptome was investigated through whole transcriptome sequencing.MSCs were pretreated with 5-pulse nsPEFs(100 ns at 10 kV/cm,1 Hz),followed by total RNA isolation.Each transcript was normalized by fragments per kilobase per million.Fold change and difference significance were applied to screen the differentially expressed genes(DEGs).Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed to elucidate gene functions,complemented by quantitative polymerase chain reaction verification.RESULTS In total,263 DEGs were discovered,with 92 upregulated and 171 downregulated.DEGs were predominantly enriched in epithelial cell proliferation,osteoblast differentiation,mesenchymal cell differentiation,nuclear division,and wound healing.Regarding cellular components,DEGs are primarily involved in condensed chromosome,chromosomal region,actin cytoskeleton,and kinetochore.From aspect of molecular functions,DEGs are mainly involved in glycosaminoglycan binding,integrin binding,nuclear steroid receptor activity,cytoskeletal motor activity,and steroid binding.Quantitative real-time polymerase chain reaction confirmed targeted transcript regulation.CONCLUSION Our systematic investigation of the wide-ranging transcriptional pattern modulated by nsPEFs revealed the differential expression of 263 mRNAs,2 miRNAs,and 65 lncRNAs.Our study demons

关键词： Nanosecond pulsed electric fields Whole transcriptome sequencing Mesenchymal stem cells Genetic response Stem cell engineering

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Classification of anatomical morphology of cystic duct and its association with gallstone

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 307-317页

作者： jia-Hai Zhu Song-Ling Zhao qiang Kang Ya Zhu Li-Xin Liu Hao Zou Department of Hepatobiliary Pancreatic Surgery The Second Affiliated Hospital of Kunming Medical UniversityKunming 650106Yunnan ProvinceChina Department of Hepatobiliary Surgery The Second Affiliated HospitalKunming Medical UniversityKunming 650106Yunnan ProvinceChina

BACKGROUND Gallstones are common lesions that often require surgical intervention.Laparo-scopic cholecystectomy is the treatment of choice for symptomatic gallstones.Preoperatively,the anatomical morphology of the cystic duct(CD),needs to be accurately recognized,especially when anatomical variations occur in the CD,which is otherwise prone to bile duct injury.However,at present,there is no optimal classification system for CD morphology applicable in clinical practice,and the relationship between anatomical variations in CDs and gallstones remains to be explored.AIM To create a more comprehensive clinically applicable classification of the morphology of CD and to explore the correlations between anatomic variants of CD and gallstones.METHODS A total of 300 patients were retrospectively enrolled from October 2021 to January 2022.The patients were divided into two groups:The gallstone group and the nongallstone group.Relevant clinical data and anatomical data of the CD based on magnetic resonance cholangiopancreatography(MRCP)were collected and analyzed to propose a morphological classification system of the CD and to explore its relationship with gallstones.Multivariate analysis was performed using logistic regression analyses to identify the independent risk factors using variables that were significant in the univariate analysis.RESULTS Of the 300 patients enrolled in this study,200(66.7%)had gallstones.The mean age was 48.10±13.30 years,142(47.3%)were male,and 158(52.7%)were female.A total of 55.7%of the patients had a body mass index(BMI)≥24 kg/m2.Based on the MRCP,the CD anatomical typology is divided into four types:Type I:Linear,type II:n-shaped,type III:S-shaped,and type IV:W-shaped.Univariate analysis revealed differences between the gallstone and nongallstone groups in relation to sex,BMI,cholesterol,triglycerides,morphology of CD,site of CD insertion into the extrahepatic bile duct,length of CD,and angle between the common hepatic duct and CD.According to the multivariate analysis,female,BMI(≥24 kg/m2)

关键词： Cystic duct Gallstone Classification Anatomy Magnetic resonance cholangiopancreatography Risk factor

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Electromagnetic Performance Analysis of Variable Flux Memory Machines with Series-magnetic-circuit and Different Rotor Topologies

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 3-11页

作者： qiang Wei Z.Q.Zhu Yan jia jianghua Feng Shuying Guo Yifeng Li Shouzhi Feng Department of Electronic and Electrical Engineering The University of SheffieldSheffield S13JDU.K. IEEE the CRRC Zhuzhou Institute Company Ltd. Zhuzhou 412001China

In this paper,the electromagnetic performance of variable flux memory(VFM)machines with series-magnetic-circuit is investigated and compared for different rotor topologies.Based on a V-type VFM machine,five topologies with different interior permanent magnet(IPM)arrangements are evolved and optimized under same constrains.Based on two-dimensional(2-D)finite element(FE)method,their electromagnetic performance at magnetization and demagnetization states is evaluated.It reveals that the iron bridge and rotor lamination region between constant PM(CPM)and variable PM(VPM)play an important role in torque density and flux regulation(FR)capabilities.Besides,the global efficiency can be improved in VFM machines by adjusting magnetization state(MS)under different operating conditions.

关键词： Memory machine Permanent magnet Rotor topologies Series magnetic circuit Variable flux

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Loosely coordinating diluted highly concentrated electrolyte toward -60℃ Li metal batteries

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Journal of Energy Chemistry 2024年第3期90卷 380-387,I0009页

作者： Han Zhang Ziqi Zeng qiang Wu Xinlan Wang Mingsheng Qin Sheng Lei Shijie Cheng jia Xie State Key Laboratory of Advanced Electromagnetic Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferior lithium metal anode(LMA) compatibility and sluggish Li^(+) desolvation.Here,we demonstrate that cyclopentylmethyl ether(CPME) based diluted high-concentration electrolyte(DHCE)enables-60℃ LMBs operation.By leveraging the loose coordination between Li^(+) and CPME,such developed electrolyte boosts the formation of ion clusters to derive anion-dominant interfacial chemistry for enhancing LMA compatibility and greatly accelerates Li^(+) desolvation kinetics.The resulting electrolyte demonstrates high Coulombic efficiencies(CE),providing over 99.5%,99.1%,98.5% and 95% at 25,-20,-40,and-60℃respectively.The assembled Li-S battery exhibits remarkable cyclic stability in-20,and-40℃ at 0.2 C charging and 0.5 C discharging.Even at-60℃,Li-S cell with this designed electrolyte retains> 70% of the initial capacity over 170 cycles.Besides,lithium metal coin cell and pouch cell with10 mg cm^(-2) high S cathode loading exhibit cycling stability at-20℃.This work offers an opportunity for rational designing electrolytes toward low temperature LMBs.

关键词： Lithium metal batteries -60℃operation Lithium metal anode compatibility Li^(+) desolvation kinetics

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