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Experimental and numerical study on dynamic mechanical behaviors of shale under true triaxial compression at high strain rate

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International Journal of Mining Science and Technology 2024年第2期34卷 149-165页

作者： Xiaoping Zhou Linyuan Han jing bi Yundong Shou School of Civil Engineering Wuhan UniversityWuhan 430072China College of Civil Engineering Guizhou UniversityGuiyang 550025China

High-energy gas fracturing of shale is a novel,high efficacy and eco-friendly mining technique,which is a typical dynamic perturbing behavior.To effectively extract shale gas,it is important to understand the dynamic mechanical properties of shale.Dynamic experiments on shale subjected to true triaxial compression at different strain rates are first conducted in this research.The dynamic stress-strain curves,peak strain,peak stress and failure modes of shale are investigated.The results of the study indicate that the intermediate principal stress and the minor principal stress have the significant influence on the dynamic mechanical behaviors,although this effect decreases as the strain rate increases.The characteristics of compression-shear failure primarily occur in shale subjected to triaxial compression at high strain rates,which distinguishes it from the fragmentation characteristics observed in shale under dynamic uniaxial compression.Additionally,a numerical three-dimensional Split Hopkinson Pressure Bar(3D-SHPB),which is established by coupling PFC3D and FLAC3D methods,is validated to replicate the laboratory characteristics of shale.The dynamic mechanical characteristics of shale subjected to different confining stresses are systematically investigated by the coupling PFC3D and FLAC3D method.The numerical results are in good agreement with the experimental data.

关键词： Dynamic behaviors True triaxial compression High strain rates Dynamic failure mechanism PFC3D-FLAC3D coupled method

Feedback of Efficient Shock Acceleration on Magnetic-field Structure Inside Young Type Ia Supernova Remnants

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Research in Astronomy and Astrophysics 2024年第6期24卷 236-246页

作者： Jun-Yu Shen bi-wen Bao Li Zhang Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan Province Yunnan University Key Laboratory of Statistical Modeling and Data Analysis of Yunnan Province Yunnan University

Using an effective adiabatic index γeffto mimic the feedback of efficient shock acceleration, we simulate the temporal evolution of a young type Ia supernova remnant （SNR） with two different background magnetic field（BMF） topologies:a uniform and a turbulent BMF. The density distribution and magnetic-field characteristics of our benchmark SNR are studied with two-dimensional cylindrical magnetohydrodynamic simulations. When γeffis considered, we find that:（1） the two-shock structure shrinks and the downstream magnetic-field orientation is dominated by the Rayleigh–Taylor instability structures;（2） there exists more quasi-radial magnetic fields inside the shocked region; and （3） inside the intershock region, both the quasi-radial magnetic energy density and the total magnetic energy density are enhanced:in the radial direction, with γeff=1.1, they are amplified about 10–26 times more than those with γeff=5/3. While in the angular direction, the total magnetic energy densities could be amplified about 350 times more than those with γeff=5/3, and there are more grid cells within the intershock region where the magnetic energy density is amplified by a factor greater than 100.

关键词： ISM: magnetic fields ISM: supernova remnants magnetohydrodynamics (MHD) methods: numerical

Numerical Investigations on Harbor Oscillations Induced by Falling Objects

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China Ocean Engineering 2023年第3期37卷 458-470页

作者： GAO Jun-liang bi wen-jing ZHANG Jian ZANG Jun School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Key Laboratory of Port Waterway and Sedimentation Engineering of MOTNanjing Hydraulic Research InstituteNanjing 210029China Key Laboratory of Water Security Guarantee in Guangdong-Hong Kong-Marco Greater Bay Area of Ministry of Water Resources Guangzhou 510611China Centre for Infrastructure Geotechnical and Water Engineering(IGWE)Department of Architecture and Civil EngineeringUniversity of BathBA27AYUK

In this paper,the open-sourced computational fluid dynamics software,OpenFOAM~?,is used to study the fluctuation phenomenon of the water body inside a horizontally one-dimensional enclosed harbor basin with constant water depth triggered by falling wedges with various horizontal falling positions,initial falling velocities and masses.Based on both Fourier transfo rm analysis and wavelet spectrum analysis for the time series of the free surface elevations inside the harbor basin,it is found for the first time that the wedge falling inside the harbor can directly trigger harbor resonance.The influences of the three factors(including the horizontal falling position,the initial falling velocity,and the mass)on the response amplitudes of the lowest three resonant modes are also investigated.The results show that when the wedge falls on one of the nodal points of a resonant mode,the mode would be remarkably suppressed.Conversely,when the wedge falls on one of the anti-nodal points of a resonant mode,the mode would be evidently triggered.The initial falling velocity of the wedge mainly has a remarkable effect on the response amplitude of the most significant mode,and the latter shows a gradual increase trend with the increase of the former.While for the other two less significant modes,their response amplitudes fluctuate around certain constant values as the initial falling velocity rises.In general,the response amplitudes of all the lowest three modes are shown to gradually increase with the mass of the wedge.

关键词： harbor oscillations seiches falling objects resonant mode response amplitude

Treatment patterns and survival outcomes in patients with nonmetastatic early-onset pancreatic cancer

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World Journal of Gastroenterology 2024年第12期30卷 1739-1750页

作者： Le-Tian Zhang Ying Zhang bi-Yang Cao Chen-Chen Wu jing Wang Graduate School Chinese PLA Medical SchoolBeijing 100853China Department of Radiation Oncology First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Internal Medicine Hospital of University of Science and Technology BeijingBeijing 100083China Department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

BACKGROUND The incidence of patients with early-onset pancreatic cancer(EOPC;age≤50 years at diagnosis)is on the rise,placing a heavy burden on individuals,families,and society.The role of combination therapy including surgery,radiotherapy,and chemotherapy in non-metastatic EOPC is not well-defined.AIM To investigate the treatment patterns and survival outcomes in patients with non-metastatic EOPC.METHODS A total of 277 patients with non-metastatic EOPC who were treated at our institution between 2017 and 2021 were investigated retrospectively.Overall survival(OS),disease-free survival,and progression-free survival were estimated using the Kaplan-Meier method.Univariate and multivariate analyses with the Cox proportional hazards model were used to identify prognostic factors.RESULTS With a median follow-up time of 34.6 months,the 1-year,2-year,and 3-year OS rates for the entire cohort were 84.3%,51.5%,and 27.6%,respectively.The median OS of patients with localized disease who received surgery alone and adjuvant therapy(AT)were 21.2 months and 28.8 months,respectively(P=0.007).The median OS of patients with locally advanced disease who received radiotherapy-based combination therapy(RCT),surgery after neoadjuvant therapy(NAT),and chemotherapy were 28.5 months,25.6 months,and 14.0 months,respectively(P=0.002).The median OS after regional recurrence were 16.0 months,13.4 months,and 8.9 months in the RCT,chemotherapy,and supportive therapy groups,respectively(P=0.035).Multivariate analysis demonstrated that carbohydrate antigen 19-9 level,pathological grade,T-stage,N-stage,and resection were independent prognostic factors for non-metastatic EOPC.CONCLUSION AT improves postoperative survival in localized patients.Surgery after NAT and RCT are the preferred therapeutic options for patients with locally advanced EOPC.

关键词： Pancreatic cancer Early-onset Non-metastatic Multimodal treatment Radiotherapy Overall survival

Abnormal function of EPHA2/p.R957P mutant in congenital cataract

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1007-1017页

作者： jing-Jin Zhang Zong-Fu Cao bi-Ting Zhou Ju-Hua Yang Zhong Li Shuang Lin Xiao-Le Chen Nan-wen Zhang Qin Ye Xu Ma Yi-Hua Zhu Department of Ophthalmology the First Affiliated Hospital of Fujian Medical UniversityFujian Institute of OphthalmologyFujian Provincial Clinical Medical Research Center of Eye Diseases and OptometryFuzhou 350005Fujian ProvinceChina Department of Ophthalmology National Regional Medical CenterBinhai Campus of the First Affiliated HospitalFujian Medical UniversityFuzhou 350005Fujian ProvinceChina Chinese Academy of Medical Sciences&Peking Union Medical College Beijing 100000China National Human Genetic Resources Center National Research Institute for Family PlanningBeijing 100081China Department of bioengineering and biopharmaceutics School of PharmacyFujian Medical UniversityFuzhou 350004Fujian ProvinceChina

AIM:To identify genetic defects in a Chinese family with congenital posterior polar cataracts and assess the pathogenicity.METHODS:A four-generation Chinese family affected with autosomal dominant congenital cataract was recruited.Nineteen individuals took part in this study including 5 affected and 14 unaffected individuals.Sanger sequencing targeted hot-spot regions of 27 congenital cataract-causing genes for variant discovery.The pathogenicity of the variant was evaluated by the guidelines of American College of Medical Genetics and InterVar software.Confocal microscopy was applied to detect the subcellular localization of fluorescence-labeled ephrin type-A receptor 2(EPHA2).Co-immunoprecipitation assay was implemented to estimate the interaction between EphA2 and other lens membrane proteins.The mRNA and protein expression were analyzed by reverse transcription-polymerase chain reaction(qRT-PCR)and Western blotting assay,respectively.The cell migration was analyzed by wound healing assay.Zebrafish model was generated by ectopic expression of human EPHA2/p.R957P mutant to demonstrate whether the mutant could cause lens opacity in vivo.RESULTS:A novel missense and pathogenic variant c.2870G>C was identified in the sterile alpha motif(SAM)domain of EPHA2.Functional studies demonstrated the variant’s impact:reduced EPHA2 protein expression,altered subcellular localization,and disrupted interactions with other lens membrane proteins.This mutant notably enhanced human lens epithelial cell migration,and induced a central cloudy region and roughness in zebrafish lenses with ectopic expression of human EPHA2/p.R957P mutant under differential interference contrast(DIC)optics.CONCLUSION:Novel pathogenic c.2870G>C variant of EPHA2 in a Chinese congenital cataract family contributes to disease pathogenesis.

关键词： congenital cataract EPHA2 missense variant function analysis

The acceptance of traditional Chinese medicine among patients with Parkinson's disease:A hospital survey

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Journal of Integrative Medicine 2024年第2期22卷 180-187页

作者： Peng Wang jing Hong Zhu-qian Tang bi-zhen Gong Xiao-rong Qi Han Jiang Bo Pan Qi Chen Postgraduate School Medical School of Chinese People’s Liberation ArmyBeijing 100853China Senior Department of Traditional Chinese Medicine the Sixth Medical Center of PLA General HospitalBeijing 100853China Department of Integration of Chinese and Western Medicine School of Basic Medical SciencesPeking UniversityBeijing 100191China Department of Integrative Oncology the First Affiliated Hospital of Naval Medical UniversityShanghai 200433China School of Traditional Chinese Medicine Naval Medical UniversityShanghai 200433China School of Pharmacy Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina Department of Dermatology the First Clinical Medical CollegeAnhui University of Chinese MedicineHefei 230012Anhui ProvinceChina

Objective:The efficacy of medications for Parkinson’s disease(PD)tend to decline over time,which has a serious impact on patients’health and quality of life.To some extent,traditional Chinese medicine(TCM)can resolve the distressing problem of ineffective dopaminergic medication in PD patients.The purpose of this study was to investigate the attitude,acceptance,and independent predictors of TCM in PD patients admitted to the outpatient department of a tertiary hospital.Methods:A cross-sectional study of PD patients was conducted in the outpatient department of a large tertiary hospital in Beijing from March 2022 to June 2023.A self-report questionnaire was developed to investigate PD patients’attitudes and acceptance of TCM based on the questionnaire.Multivariate logistic regression analyses were also performed to further clarify the independent predictors influencing patients’adoption of TCM therapy.Results:A total of 397 patients completed the questionnaire,of which 78.09%were willing to be treated with TCM and 21.91%indicated that they were not willing to use TCM.Multifactorial logistic regression analysis showed that several parameters were correlated with a patient’s willingness to include TCM in their therapeutic regime.These included education level of a bachelor’s degree(odds ratio[OR)=8.554;95%confidence interval[CI]:4.112–17.794;P<0.001,vs junior high school education),living in an urban setting(OR=8.022;95%CI:4.577–14.060;P<0.001,vs rural),having other underlying diseases(OR=5.126;95%CI:3.078–8.537;P<0.001,vs none),having previously used TCM(OR=3.083;95%CI:1.852–5.134;P<0.001,vs not used),believing that TCM therapy is safe(OR=3.530;95%CI:1.446–8.616;P=0.006,vs not thought),believing that TCM therapy is effective(OR=3.859;95%CI:1.482–10.047;P=0.006,vs not understood),and being willing to discuss ongoing TCM therapy with an attending physician(OR=62.468;95%CI:30.350–128.574;P<0.001,vs not informed).Conclusion:This study initially investigated the acceptance,attitude,and independent predictors of TCM use

关键词： Parkinson's disease Traditional Chinese medicine Cross-sectional study

Efficient and fair PPO-based integrated scheduling method for multiple tasks of SATech-01 satellite

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Chinese Journal of Aeronautics 2024年第2期37卷 417-430页

作者： Qi SHI Lu LI Ziruo FANG Xingzi bi Huaqiu LIU Xiaofeng ZHANG wen CHEN Jinpei YU Shanghai Satellite Network Research Institute CO. LTDShanghai 201210China Innovation Academy for Microsatellites of Chinese Academy of Sciences Shanghai 201306China University of Chinese Academy of Sciences Beijing 100039China

SATech-01 is an experimental satellite for space science exploration and on-orbit demonstration of advanced technologies.The satellite is equipped with 16 experimental payloads and supports multiple working modes to meet the observation requirements of various payloads.Due to the limitation of platform power supply and data storage systems,proposing reasonable mission planning schemes to improve scientific revenue of the payloads becomes a critical issue.In this article,we formulate the integrated task scheduling of SATech-01 as a multi-objective optimization problem and propose a novel Fair Integrated Scheduling with Proximal Policy Optimization(FIS-PPO)algorithm to solve it.We use multiple decision heads to generate decisions for each task and design the action mask to ensure the schedule meeting the platform constraints.Experimental results show that FIS-PPO could push the capability of the platform to the limit and improve the overall observation efficiency by 31.5%compared to rule-based plans currently used.Moreover,fairness is considered in the reward design and our method achieves much better performance in terms of equal task opportunities.Because of its low computational complexity,our task scheduling algorithm has the potential to be directly deployed on board for real-time task scheduling in future space projects.

关键词： Satellite observatories SATech-01 Multi-modes platform Scheduling algorithms Reinforcement learning Proximal Policy Optimization(PPO)

High-throughput discovery of highly selective reversible hMAO-B inhibitors based on at-line nanofractionation

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1772-1786页

作者： Yu Fan Jincai Wang jingyi Jian Yalei wen Jiahao Li Hao Tian Jacques Crommen Wei bi Tingting Zhang Zhengjin Jiang Institute of Pharmaceutical Analysis/Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research/International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education(MOE)of China/College of Pharmacy Jinan UniversityGuangzhou 510632China KU Leuven-University of Leuven Pharmaceutical AnalysisDepartment of Pharmaceutical and Pharmacological SciencesLeuven 3000Belgium Laboratory of Analytical Pharmaceutical Chemistry Department of Pharmaceutical SciencesCIRMUniversity of LiegeLiege B-4000Belgium Department of Neurology the First Affiliated Hospital of Jinan University/Clinical Neuroscience Institutethe First Affiliated Hospital of Jinan UniversityGuangzhou 510630China

Human monoamine oxidase B(hMAO-B)has emerged as a pivotal therapeutic target for Parkinson's disease.Due to adverse effects and shortage of commercial drugs,there is a need for novel,highly selective,and reversible hMAO-B inhibitors with good blood-brain barrier permeability.In this study,a high-throughput at-line nanofractionation screening platform was established with extracts from Chuanxiong Rhizoma,which resulted in the discovery of 75 active compounds,including phenolic acids,volatile oils,and phthalides,two of which were highly selective novel natural phthalide hMAO-B inhibitors that were potent,selective,reversible and had good blood‒brain permeability.Molecular docking and molecular dynamics simulations elucidated the inhibition mechanism.Sedanolide(IC_(50)=103 nmol/L;SI=645)and neocnidilide(IC_(50)=131 nmol/L;SI=207)demonstrated their excellent potential as hMAO-B inhibitors.They offset the limitations of deactivating enzymes associated with irreversible hMAO-B inhibitors such as rasagiline.In SH-SY5Y cell assays,sedanolide(EC_(50)=0.962μmol/L)and neocnidilide(EC_(50)=1.161μmol/L)exhibited significant neuroprotective effects,comparable to the positive drugs rasagiline(EC_(50)=0.896μmol/L)and safinamide(EC_(50)=1.079μmol/L).These findings underscore the potential of sedanolide as a novel natural hMAO-B inhibitor that warrants further development as a promising drug candidate.

关键词： Human monoamine oxidase B inhibitors High-throughput screening At-linenanofractionation Parkinson's disease Cellular neuroprotection Traditional Chinese medicines(TCMs)

CALD1 facilitates epithelial-mesenchymal transition progression in gastric cancer cells by modulating the PI3K-Akt pathway

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 1029-1045页

作者： wen-Qian Ma Ming-Chang Miao Ping-An Ding bi-Bo Tan wen-Bo Liu Shuo Guo Li-Mian Er Zhi-Dong Zhang Qun Zhao Department of Endoscopy The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hebei ProvinceChina Hebei Key Laboratory of Precision Diagnosis and Comprehensive Treatment of Gastric Cancer Shijiazhuang 050011Hebei ProvinceChina Department of Radiotherapy The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hebei ProvinceChina The Third Department of Surgery The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011Hebei ProvinceChina

BACKGROUND CALD1 has been discovered to be abnormally expressed in a variety of malignant tumors,including gastric cancer(GC),and is associated with tumor progression and immune infiltration;however,the roles and mechanisms of CALD1 in epithe-lial-mesenchymal transition(EMT)in GC are unknown.AIM To investigate the role and mechanism of CALD1 in GC progression,invasion,and migration.METHODS In this study,the relationship between CALD1 and GC,as well as the possible network regulatory mechanisms of CALD1,was investigated by bioinformatics and validated by experiments.CALD1-siRNA was synthesized and used to trans-fect GC cells.Cell activity was measured using the CCK-8 method,cell migration and invasive ability were measured using wound healing assay and Transwell assay,and the expression levels of relevant genes and proteins in each group of cells were measured using qRT-PCR and Western blot.A GC cell xenograft model RESULTS bioinformatics results showed that CALD1 was highly expressed in GC tissues,and CALD1 was significantly higher in EMT-type GC tissues than in tissues of other types of GC.The prognosis of patients with high expression of CALD1 was worse than that of patients with low expression,and a prognostic model was constructed and evaluated.The experimental results were consistent with the results of the bioinformatics analysis.The expression level of CALD1 in GC cell lines was all higher than that in gastric epithelial cell line GES-1,with the strongest expression found in AGS and MKN45 cells.Cell activity was significantly reduced after CALD1-siRNA trans-fection of AGS and MKN45 cells.The ability of AGS and MKN45 cells to migrate and invade was reduced after CALD1-siRNA transfection,and the related mRNA and protein expression was altered.According to bioinfor-matics findings in GC samples,the CALD1 gene was significantly associated with the expression of members of the PI3K-AKT-mTOR signaling pathway as well as the EMT signaling pathway,and was closely related to the PI3K-Akt signaling pathway.Experimen

关键词： Gastric tumor CALD1 Epithelial-mesenchymal transition Gene disruption Invasion Migration bioinformatics