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An adaptive finite-difference method for seismic traveltime modeling based on 3D eikonal equation

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Petroleum Science 2024年第1期21卷 195-205页

作者： Bao-Ping Qiao qing-qing Li Wei-guang He Dan Zhao Qu-Bo Wu CNNC Beijing Research Institute of Uranium Geology Beijing 100029China National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580ShangdongChina SINOPEC Geophysical Research Institute Nanjing211103JiangsuChina

3D eikonal equation is a partial differential equation for the calculation of first-arrival traveltimes and has been widely applied in many scopes such as ray tracing,source localization,reflection migration,seismic monitoring and tomographic *** recent years,many advanced methods have been developed to solve the 3D eikonal equation in heterogeneous ***,there are still challenges for the stable and accurate calculation of first-arrival traveltimes in 3D strongly inhomogeneous *** this paper,we propose an adaptive finite-difference(AFD)method to numerically solve the 3D eikonal *** novel method makes full use of the advantages of different local operators characterizing different seismic wave types to calculate factors and traveltimes,and then the most accurate factor and traveltime are adaptively selected for the convergent updating based on the Fermat *** with global fast sweeping describing seismic waves propagating along eight directions in 3D media,our novel method can achieve the robust calculation of first-arrival traveltimes with high precision at grid points either near source point or far away from source point even in a velocity model with large and sharp *** numerical examples show the good performance of the AFD method,which will be beneficial to many scientific applications.

关键词： 3D eikonal equation Accurate traveltimes Global fast sweeping 3D inhomogeneous media Adaptive finite-difference method

Evaluation of the efficacy and safety of endoscopic band ligation in the treatment of bleeding from mild to moderate gastric varices type 1

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World Journal of Gastroenterology 2024年第5期30卷 440-449页

作者： Yue deng Ya Jiang Tong Jiang Ling Chen Hai-Jun Mou Bi-guang Tuo Guo-qing Shi Department of Gastroenterology Digestive Disease HospitalThe Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Gastroenterology Guizhou Hospital of the First Affiliated HospitalSun Yat-sen UniversityGuiyang 550000Guizhou ProvinceChina Department of Gastroenterology Yinjiang Autonomous County People’s HospitalTongren 554300Guizhou ProvinceChina

BACKGROUND According to practice guidelines,endoscopic band ligation(EBL)and endoscopic tissue adhesive injection(TAI)are recommended for treating bleeding from esophagogastric ***,EBL and TAI are known to cause serious complications,such as hemorrhage from dislodged ligature rings caused by EBL and hemorrhage from operation-related ulcers resulting from ***,the optimal therapy for mild to moderate type 1 gastric variceal hemorrhage(GOV1)has not been ***,the aim of this study was to discover an individualized treatment for mild to moderate *** To compare the efficacy,safety and costs of EBL and TAI for the treatment of mild and moderate *** A clinical analysis of the data retrieved from patients with mild or moderate GOV1 gastric varices who were treated under endoscopy was also *** were allocated to an EBL group or an endoscopic TAI *** differences in the incidence of varicose relief,operative time,operation success rate,mortality rate within 6 wk,rebleeding rate,6-wk operation-related ulcer healing rate,complication rate and average operation cost were compared between the two groups of *** The total effective rate of the two treatments was similar,but the efficacy of EBL(66.7%)was markedly better than that of TAI(39.2%)(P<0.05).The operation success rate in both groups was 100%,and the 6-wk mortality rate in both groups was 0%.The average operative time(26 min)in the EBL group was significantly shorter than that in the TAI group(46 min)(P<0.01).The rate of delayed postoperative rebleeding in the EBL group was significantly lower than that in the TAI group(11.8%vs 45.1%)(P<0.01).At 6 wk after the operation,the healing rate of operation-related ulcers in the EBL group was 80.4%,which was significantly greater than that in the TAI group(35.3%)(P<0.01).The incidence of postoperative complications in the two groups was *** average cost and other related economic factors were g

关键词： Gastric varices Type 1 gastric variceal hemorrhage Endoscopic band ligation Tissue adhesive injection

Jianpi qinghua Formula Alleviates Diabetic Myocardial Injury Through Inhibiting JunB/c-Fos Expression

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Current Medical Science 2024年第1期44卷 144-155页

作者： Lin WANG qing-guang CHEN Hao LU Department of Endocrinology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Traditional Chinese Medicine Naval Medical UniversityShanghai 200433China

Objective Diabetic cardiomyopathy(DCM)represents a substantial risk factor for heart failure and increased mortality in individuals afflicted with diabetes mellitus(DM).DCM typically manifests as myocardial fibrosis,myocardial hypertrophy,and impaired left ventricular diastolic *** the clinical utility of the Jianpi qinghua(JPQH)formula has been established in treating diabetes and insulin resistance,its potential efficacy in alleviating diabetic cardiomyopathy remains *** study aims to investigate the impact and underlying molecular mechanisms of the JPQH formula(JPQHF)in ameliorating myocardial injury in nonobese diabetic rats,specifically focusing on apoptosis and *** Wistar rats were assigned as the normal control group(CON),while Goto-Kakizaki(GK)rats were randomly divided into three groups:DM,DM treated with the JPQHF,and DM treated with metformin(MET).Following a 4-week treatment regimen,various biochemical markers related to glucose metabolism,cardiac function,cardiac morphology,and myocardial ultrastructure in GK rats were *** sequencing was utilized to analyze differential gene expression and identify potential therapeutic *** vitro experiments involved high glucose to induce apoptosis and inflammation in H9c2 *** viability was evaluated using CCK-8 assay,apoptosis was monitored via flow cytometry,and the production of inflammatory cytokines was measured using quantitative real-time PCR(qPCR)and *** expression levels were determined by Western blotting *** investigation also incorporated the use of MAPK inhibitors to further elucidate the mechanism at both the transcriptional and protein *** The JPQHF group exhibited significant reductions in interventricular septal thickness at end-systole(IVSs)and left ventricular internal diameter at end-systole and end-diastole(LVIDs and LVIDd).JPQHF effectively suppressed high glucose-induced activation of IL-1βand caspase 3 in

关键词： Jianpi qinghua formula diabetic cardiomyopathy AP-1 transcription factor apoptosis inflammation

Rational design multi-color-emissive chemiluminescent carbon nanodots in a single solvothermal reaction

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Nano Research 2024年第6期17卷 4651-4660页

作者： guang-Song Zheng Cheng-Long Shen Yuan deng Kai-Kai Liu Jin-Hao Zang Lin Dong qing Lou Chong-Xin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Materials PhysicsMinistry of Educationand School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China

Recently,the chemiluminescence(CL)induced by carbon nanodots(CDs)has intrigued researchers’extensive interests in various applications due to its special light emission ***,the difficulty of synthesizing chemiluminescent CDs with full-spectrum emission severely hinders the further regulation of the CL emission ***,the multi-color-emissive chemiluminescent CDs are rational designed and further synthesized by regulating the sp2-hybrid core and sp3-hybrid surface from the citrate-ammonia molecular in a single solvothermal *** experimental characterizations and density functional theory calculations reveal that the higher temperature can promote the crosslinking polymerization/carbonization of carbon core and the higher protonation of solvent can determine the core size of final CDs,resulting in the variant CL emission from molecular-,crosslinking-and ***,the CL emission of the CDs can be further synthesized by tuning the luminescence chromophores in the formation process via regulating the temperature and solvent,enabling the applications of the CL CDs in illumination and information *** study paves a new technology to understand the luminescence of CDs and affords an industry translational potential over traditional chemiluminescent molecular.

关键词： carbon nanodots chemiluminescence regulation energy level alignment mechanism

The molecular genetics of PI3K/PTEN/AKT/mTOR pathway in the malformations of cortical development

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Genes & Diseases 2024年第5期11卷 252-271页

作者： qing Ma guang Chen Ying Li Zhenming Guo Xue Zhang NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics Harbin Medical UniversityHarbinHeilongjiang 150000China Department of Urology The Fourth Hospital of Harbin Medical UniversityHarbinHeilongjiang 150000China Department of Child and Adolescent Health School of Public HealthHarbin Medical UniversityHarbinHeilongjiang 150000China Institute for Regenerative Medicine Shanghai East HospitalFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200120China

Malformations of cortical development(MCD)are a group of developmental disorders characterized by abnormal cortical structures caused by genetic or harmful environmental *** kinds of MCD are caused by genetic *** is the common cause of intellectual disability and intractable *** rapid advances in imaging and sequencing technologies,the diagnostic rate of MCD has been increasing,and many potential genes causing MCD have been successively ***,the high genetic heterogeneity of MCD makes it challenging to understand the molecular pathogenesis of MCD and to identify effective targeted ***,in this review,we outline important events of cortical *** we illustrate the progress of molecular genetic studies about MCD focusing on the PI3K/PTEN/AKT/mTOR ***,we briefly discuss the diagnostic methods,disease models,and therapeutic strategies for *** information will facilitate further research on *** the role of the PI3K/PTEN/AKT/mTOR pathway in MCD could lead to a novel strategy for treating MCD-related diseases.

关键词： Epilepsy Gene mutation Genetics Malformations of cortical development PI3K/PTEN/AKT/mTOR pathway

The effects of various factors on spontaneous imbibition in tight oil reservoirs

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Petroleum Science 2024年第1期21卷 315-326页

作者： Cheng Liu Tian-Ru Wang qing You Yue-Chun Du guang Zhao Cai-Li Dai School of Energy Resources China University of GeosciencesBeijing100083PR China School of Petroleum Engineering China University of PetroleumQingdao266580ShandongPR China

Slickwater fracturing fluids have gained widespread application in the development of tight oil reservoirs. After the fracturing process, the active components present in slickwater can directly induce spontaneous imbibition within the reservoir. Several variables influence the eventual recovery rate within this procedure, including slickwater composition, formation temperature, degree of reservoir fracture development, and the reservoir characteristics. Nonetheless, the underlying mechanisms governing these influences remain relatively understudied. In this investigation, using the Chang-7 block of the Changqing Oilfield as the study site, we employ EM-30 slickwater fracturing fluid to explore the effects of the drag-reducing agent concentration, imbibition temperature, core permeability, and core fracture development on spontaneous imbibition. An elevated drag-reducing agent concentration is observed to diminish the degree of medium and small pore utilization. Furthermore, higher temperatures and an augmented permeability enhance the fluid flow properties, thereby contributing to an increased utilization rate across all pore sizes. Reduced fracture development results in a lower fluid utilization across diverse pore types. This study deepens our understanding of the pivotal factors affecting spontaneous imbibition in tight reservoirs following fracturing. The findings act as theoretical, technical, and scientific foundations for optimizing fracturing strategies in tight oil reservoir transformations.

关键词： Tight oil reservoir Spontaneous imbibition Nuclear magnetic resonance Slickwater fracturing fluid Fluid utilization degree

Variable projection algorithms with sparse constraint for separable nonlinear models

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Control Theory and Technology 2024年第1期22卷 135-146页

作者： Hui-Lang Xu guang-Yong Chen Si-qing Cheng Min Gan Jing Chen College of Computer and Data Science Fuzhou UniversityFuzhou350116FujianChina Fujian Key Laboratory of Network Computing and Intelligent Information Processing Fuzhou UniversityFuzhou350116FujianChina Key Laboratory of Intelligent Metro of Universities in Fujian Fuzhou UniversityFuzhou350116FujianChina Engineering Research Center of Big Data Intelligence Ministry of EducationFuzhou UniversityFuzhou350116FujianChina School of Science Jiangnan UniversityWuxi214122JiangsuChina

Separable nonlinear models are widely used in various fields such as time series analysis, system modeling, and machine learning, due to their flexible structures and ability to capture nonlinear behavior of data. However, identifying the parameters of these models is challenging, especially when sparse models with better interpretability are desired by practitioners. Previous theoretical and practical studies have shown that variable projection (VP) is an efficient method for identifying separable nonlinear models, but these are based on \(L_2\) penalty of model parameters, which cannot be directly extended to deal with sparse constraint. Based on the exploration of the structural characteristics of separable models, this paper proposes gradient-based and trust-region-based variable projection algorithms, which mainly solve two key problems: how to eliminate linear parameters under sparse constraint;and how to deal with the coupling relationship between linear and nonlinear parameters in the model. Finally, numerical experiments on synthetic data and real time series data are conducted to verify the effectiveness of the proposed algorithms.

关键词： Variable projection(VP) Non-smooth constraint Separable nonlinear models

Bioinspired design of integral molded Janus silk fibroin-MXene evaporator for efficient solar vapor generation

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Nano Research 2024年第4期17卷 2824-2835页

作者： Ling-qing Kong Zhi-Cheng Zeng guang-Zong Min Zhao-Hui Meng Guo-qing Meng Xiao-Xiao Guo Nai-Bo Lin Xiang-Yang Liu The Higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Research Center of Biomedical Engineering of XiamenDepartment of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005China The State Key Laboratory of Marine Environmental Science(MEL) College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China

Solar vapor generation is a promising sustainable technology that uses solar distillation to produce fresh water from seawater and wastewater,helping relieve global water resource ***,inspired by naturally grown integrally molded mulberry leaves with a Janus hydrophilic and hydrophobic structure,a novel,simple,and efficient integrated molding method is proposed to break through the limitations of the traditional split manufacturing strategy and realizes the integrated formation of Janus *** on the spontaneous sedimentation characteristics of MXene in silk fibroin solution and its regulation of mesoscopic structure and hydrophilicity of silk fibroin,layered structures with different compositions and hydrophilicities were obtained in one ***,ethanol and glutaraldehyde were added to construct a physical crystallization-chemical crosslinking dual stabilization structure in silk *** evaporator has the evaporation rate of 3.07 kg·m^(-2)·h^(-1) and the efficiency of 86.8%under 1 sun and maintains high evaporation performance under various extreme test conditions including vigorous washing,repeated compression,and high-intensity ultraviolet(UV)***,the evaporator performs well in practical application scenarios,its evaporation rate in the simulated Dead Sea seawater exceeds 2.13 kg·m^(-2)·h^(-1),and more than 99.9%of the salt,heavy metal ions,oil pollution,and dyes are purified.

关键词： silk fibroin MXene bioinspired integrated molding Janus structure solar vapor generation

Will the 2022 compound heatwaveedrought extreme over the Yangtze River Basin become Grey Rhino in the future?

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Advances in Climate Change Research 2024年第3期15卷 547-556页

作者： Ai-qing FENG qing-Chen CHAO Lu-Lu LIU Ge GAO Guo-Fu WANG Xue-Jun ZHANG Qi-guang WANG China Meteorological Administration Key Laboratory for Climate Prediction Studies National Climate CentreBeijing 100081China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China China Institute of Water Resources and Hydropower Research Beijing 100038China China Meteorological Administration Training Centre China Meteorological AdministrationBeijing 100081China

The increasingly frequent and severe regional-scale compound heatwave-drought extreme events(CHDEs),driven by global warming,present formidable challenges to ecosystems,residential livelihoods,and economic ***,uncertainty persists regarding the future trend of CHDEs and their insights into regional spatiotemporal *** integrating daily meteorological data from observations in 1961-2022 and global climate models(GCMs)based on the Shared Socioeconomic Pathways,the evolution patterns of CHDEs were compared and examined among three sub-catchments of the Yangtze River Basin,and the return periods of CHDE in 2050s and 210Os were *** findings indicate that the climate during the 2022 CHDE period was the warmest and driest recorded in 1961-2022,with precipitation less than 154.5 mm and a mean daily maximum temperature 3.4°C higher than the average of 1981-2010,whereas the char-acteristics in the sub-catchments exhibited temporal and spatial *** July-August 2022,the most notable feature of CHDE was its extremeness since 1961,with return periods of~200-year in upstream,80-year in midstream,and 40-year in downstream,*** 2050,the return periods witnessed 2022 CHDE would likely be reduced by *** towards 2100,under the highest emission scenario of SSP585,it was projected to substantially increase the frequency of CHDEs,with return periods reduced to one-third in the upstream and downstream,as well as halved in the *** findings provide valuable insights into the changing risks associated with forthcoming climate extremes,emphasizing the urgency of addressing these challenges in regional management and sustainable development.

关键词： Compound extreme event Joint return period Drought Heatwave Climate change Yangtze River Basin