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An overview and perspective of identifying lunar craters

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Science China Earth Sciences 2024年第5期67卷 1395-1416页

作者： yan JIANG Changyi xu Ling CHEN State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100029China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100049China

The spatiotemporal evolution of lunar impact craters is crucial for investigating lunar interior structure,internal and external dynamic processes,and interplanetary impact *** in lunar crater identification are reviewed based on topography and gravity data,and the features and mechanisms of topographic or buried craters are analyzed regarding morphology,gravity anomalies,gravity gradients,and the underlying crust-mantle interface *** on the compiled crater catalog,the early lunar impact flux and thermal evolution are further discussed according to the basin ages and their interior *** some ancient impact basins,the crater size-frequency distribution measurements revealed age discrepancies from previous studies,suggesting that the lunar late heavy bombardment event started at~3.95 *** degraded bulge structures of the crust-mantle interface beneath mare basins reveal that these basins formed on the lunar crust surface under high-temperature conditions and underwent prolonged relaxation compared to highland ***,we reveal that the up-to-date identification of lunar buried craters remains inaccurate and incomplete,preventing us from accurately reconstructing lunar and interplanetary impact ***,we propose that a gravity model constructed using localized orthogonal basis functions can be useful for identifying lunar craters.

关键词： Moon Gravity field Craters Impact flux Early evolution

A calibration and compensation method for an industrial robot with high accuracy harmonic reducers

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Science China(Technological Sciences) 2024年第3期67卷 725-739页

作者： ZHAO Yiyang LIU xun CAO JiaBin LIU JinYu xu yan yan WeiXin School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Computer and Control Engineering Northeast Forestry UniversityHarbin 150040China

Industrial serial robots need high stiffness to keep absolute pose accuracy and meet the requirements in practical applications. However, the weak stiffness feature of robot joints and the payloads affected on robot end-effector, which will also increase the pose error of robot. Especially, the existing calibration methods often consider under no-payload condition without discussing the payload state. In this paper, we report a new industrial serial robot composed by a new harmonic reducer: Model-Y, based on high accuracy and high stiffness, and a kinematic parameter calibration algorithm which is based on a harmonic reducer forcedeformation model. To decrease the accuracy effects of payload, an iterative calibration method for kinematic parameters with payload situation was proposed. Simulation and experiments are conducted to verify the effectiveness of the proposed calibration method using the self-developed industrial serial robot. The results show a remarkably improved accuracy in absolute position and orientation with the robot's payload range. The position mean error has 70% decreased to 0.1 mm and the orientation mean error diminished to less than 0.01° after calibration with compensation. Additionally, online linear and circular tests are carried out to evaluate the position error of the robot during large-scale spatial and low-speed continuous movement. The accuracy is consistent with the previous calibration results, indicating the effectiveness and advantages of the proposed strategy in this article.

关键词： industrial serial robot Model-Y harmonic calibration stiffness model online compensation

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Solubility determination and comparison ofβ-HMX and RDX in two binary mixed solvents(acetonitrile+water,nitric acid+water)

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Chinese Journal of Chemical Engineering 2024年第5期69卷 238-249页

作者： Yuehua Yao Fan wang Yinguang xu Zishuai xu Lizhen Chen Jianlong wang School of Chemistry and Chemical Engineering North University of ChinaTaiyuan 030051China Gansu Yinguang Chemical Industry Group Co.Ltd. Baiyin 730900China

In order to remove hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX),the main impurity,in process of polymorphic transformation of octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),the solubility ofβ-HMX and RDX in acetonitrile(ACN)+water in the temperature range of 288.15-333.15 K and in nitric acid(HNO_(3))+water in the temperature range of 298.15-333.15 K were measured by laser dynamic *** results showed that the solubility of bothβ-HMX and RDX in binary mixed solvents increased monotonously as the temperature increase at a given solvent composition or with increasing of mole fraction of solvent(ACN and nitric acid).Solubility data were well correlated by the modified Apelblat equation,Jouyban-Acree model,Yaws equation and van't Hoff equation,and the Yaws equation achieved the best fitting results according to the relative error and the mean square error ***,the solubility ofβ-HMX and RDX in binary mixed solvent was compared,based on the solubility difference and the solvent's own properties,the best separation degree ofβ-HMX and RDX was found when the mole fraction of nitric acid was 0.22 at room temperature,which provided data support for HMX crystallization in mixed *** solubility differences between RDX andβ-HMX in mixed solvents were explained from the formation of intermolecular and intramolecular hydrogen bonds.

关键词： Solubility Octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine Hexahydro-1,3,5-trinitro-1,3,5-triazine Separation Model Hydrogen bond

Alanine aminotransferase as a risk marker for new-onset metabolic dysfunction-associated fatty liver disease

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World Journal of Gastroenterology 2024年第25期30卷 3132-3139页

作者： Di wang Bing-yan Zhou Lei Xiang xu-Yong Chen Jie-Xiong Feng Department of Pediatric Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

In this editorial,we comment on the article by Chen et *** dysfunction-associated fatty liver disease(MAFLD)is a global public health burden whose incidence has risen concurrently with overweight and *** its detri-mental health impact,early identification of at-risk individuals is *** diagnosis is based on evidence of hepatic steatosis indicated by liver biopsy,imaging,or blood biomarkers,and one of the following conditions:Overweight/obesity,type 2 diabetes mellitus,or metabolic ***,in large-scale epidemiological studies,liver biopsies are not *** application of techniques such as ultrasonography,computed tomography,magnetic resonance imaging,and magnetic resonance spectroscopy is restricted by their limited sensitivity,low effectiveness,high costs,and need for specialized *** biomarkers offer several advantages,particularly in large-scale epidemiological studies or clinical scenarios where traditional imaging techniques are *** of cumulative effects of excess high-normal blood alanine aminotrans-ferase(ALT)levels of blood ALT levels could facilitate identification of at-risk patients who might not be detected through conventional imaging ***,investigating the utility of blood biomarkers in MAFLD should enhance early detection and monitoring,enabling timely inter-vention and management and improving patient outcomes.

关键词： Nonalcoholic fatty liver disease Metabolic dysfunction-associated fatty liver disease Alanine aminotransferase Screening Risk marker

The cytosolic isoform of triosephosphate isomerase,ZmTPI4,is required for kernel development and starch synthesis in maize(Zea mays L.)

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The Crop Journal 2024年第2期12卷 401-410页

作者： Wenyu Li Han wang Qiuyue xu Long Zhang yan wang Yongbiao Yu Xiangkun Guo Zhiwei Zhang Yongbin Dong Yuling Li State Key Laboratory of Wheat and Maize Crop Science Collaborative Innovation Center of Henan Grain CropsCollege of AgronomyHenan Agricultural UniversityLongzi Lake CampusZhengzhou 450046HenanChina

Triosephosphate isomerase(TPI)is an enzyme that functions in plant energy production,accumulation,and *** understand its function in maize,we characterized a maize TPI mutant,*** comparison to the wild type,zmtpi4 mutants showed altered ear development,reduced kernel weight and starch content,modified starch granule morphology,and altered amylose and amylopectin ***,ATP,and pyruvate contents were reduced,indicating ZmTPI4 was involved in *** subcellular localization confirmed ZmTPI4 as a cytosolic rather than a plastid isoform of TPI,the zmtpi4 mutant showed reduced leaf size and chlorophyll *** of ZmTPI4 in Arabidopsis led to enlarged leaves and increased seed weight,suggesting a positive regulatory role of ZmTPI4 in kernel weight and starch *** conclude that ZmTPI4 functions in maize kernel development,starch synthesis,glycolysis,and photosynthesis.

关键词： Maize Kernel Starch Weight Photosynthesis

Current and Potential Roles of Ferroptosis in Bladder Cancer

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Current Medical Science 2024年第1期44卷 51-63页

作者： Wen-xin AN Radheshyam Gupta Kun ZHAI Ya-ru wang Wan-hai xu yan CUI Department of Urology Harbin Medical University Cancer HospitalHarbin 150081China Department of Internal Medical Oncology Harbin Medical University Cancer HospitalHarbin 150081China

Ferroptosis,a type of regulated cell death driven by iron-dependent lipid peroxidation,is mainly initiated by extramitochondrial lipid peroxidation due to the accumulation of iron-dependent reactive oxygen *** is a prevalent and primitive form of cell *** cellular metabolic processes regulate ferroptosis,including redox homeostasis,iron regulation,mitochondrial activity,amino acid metabolism,lipid metabolism,and various disease-related signaling *** plays a pivotal role in cancer therapy,particularly in the eradication of aggressive malignancies resistant to conventional *** studies have explored the connection between ferroptosis and bladder cancer,focusing on its incidence and treatment *** biomolecules and tumor-associated signaling pathways,such as p53,heat shock protein 1,nuclear receptor coactivator 4,RAS-RAF-MEK,phosphatidylinositol 3-kinase-AKT-mammalian target of rapamycin,and the Hippo-tafazzin signaling system,exert a moderating influence on ferroptosis in bladder *** inducers,including erastin,artemisinin,conjugated polymer nanoparticles,and quinazolinyl-arylurea derivatives,hold promise for enhancing the effectiveness of conventional anticancer medications in bladder cancer *** conventional therapeutic drugs and treatment methods related to ferroptosis offers a promising approach for the treatment of bladder *** this review,we analyze the research on ferroptosis to augment the efficacy of bladder cancer treatment.

关键词： ferroptosis bladder cancer ferroptosis-associated tumor signaling pathway ferroptosis inducer

CFD-DEM study of impacts of the porous distributor medium on fluidization characteristics of a 2D-fluidized bed

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Particuology 2024年第4期87卷 54-73页

作者： Fei wang Yishan Zeng Hao yan School of Mechanical Engineering Hefei University of TechnologyHefei230009China

Gas-solid bubbling fluidized beds are widely used in chemical,energy,construction,and other industrial fields due to their excellent fluidization performance.2D-fluidized beds with planar rectangular columns of finite thickness are widely used in fluidized bed studies,and it is essential for understanding the hydrodynamics of gas-particle ***,the distributor(porous medium)at the bottom of the bed has a crucial influence on the fluidization performance of the 2D-fluidized *** this work,the fluidization mechanism and gas-solid dynamic characteristics of the fluidized bed under three porous media are studied by CFD-DEM coupled with the porous medium model,and the accuracy of numerical simulation is verified by a high-speed photography *** show that with the increase in the flow resistance of the porous medium,the average and standard deviation of the bubble diameter decrease,and the time and position of particles in the dead zone to participate in the core-annular flow *** a low fluidization velocity,the dead zone in the bed can be considerably reduced by increasing the flow resistance.

关键词： Fluidized bed CFD-DEM Porous medium Bubble dynamics Solid mixing

Metastatic stomach lymphoepithelioma-like carcinoma and immune checkpoint inhibitor therapy:A case report

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1436-1442页

作者： Guo-Feng Chen Jun wang Yu yan Song xu Jian Chen Department of Gastroenterology Surgery The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina Cancer Center Zhejiang UniversityHangzhou 310000Zhejiang ProvinceChina Department of Pathology The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina Department of Gastroenterology The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Pulmonary lymphoepithelioma-like carcinoma(PLELC)is a rare type of nonsmall-cell lung *** lymphoepithelioma-like carcinoma(LELC)metastasis secondary to PLELC has not been reported *** SUMMARY A 64-year-old female was admitted to our hospital for a regular gastroscopy examination with a 6-year history of surgical resection for left *** emission tomography/computed tomography suggested high accumulation of 18F-fludeoxyglucose in the gastric cardia *** gastrointestinal endoscopy confirmed a large mass at the stomach ***(IHC)of the biopsy suggested metastatic stomach *** gastrectomy showed that this 6.5 cm×5.0 cm mass was located in the stomach fundus near the *** examination showed a poorly differentiated carcinoma with prominent lymphoplasmacytic *** demonstrated that the tumor was positive for CK(AE1/AE3),p63,p40,p53,Ki-67(70%),and EGFR(3+)and negative for CK7,CK20,Her2,and *** situ hybridization analysis showed positive staining Epstein-Barr virus-encoded *** programmed cell death ligand 1(PD-L1)expression score was 98%,and the combined positive score was 100,with no evidence of microsatellite ***,the patient was unequivocally diagnosed with metastatic stomach LELC secondary to pulmonary *** discharge,this patient underwent PD-1 inhibitor treatment(toripalimab,240 mg)every 3 wk for ten cycles,and she has had no tumor *** For gastric LELC metastasis,PD-1 inhibitor therapy could become a new therapeutic approach,though there is still no evidence from large data sets to support this.

关键词： Stomach neoplasm Pulmonary lymphoepithelioma-like carcinoma Metastasis Immune checkpoint inhibitor Case report

Experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering boundary effect

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1072-1084页

作者： xuwei wang Yeshuang xu State Key Laboratory of Ocean Engineering School of Naval ArchitectureOceanand Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Key Laboratory for Digital Maintenance of Buildings and Infrastructure Department of Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

The boundary condition is a crucial factor affecting the permeability variation due to *** experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundary effect is conducted,where the hydraulic head difference(DH)varies,and the boundary includes non-loss and soil-loss *** samples are filled into seven soil storerooms connected in *** evaluation,the variation in content of fine sand(ΔR_(f))and the hydraulic conductivity of soils in each storeroom(C_(i))are *** the non-loss test,the soil sample filling area is divided into runoff,transited,and accumulated areas according to the negative or positive ΔR_(f) values.ΔR_(f) increases from negative to positive along the seepage path,and Ci decreases from runoff area to transited area and then rebounds in accumulated *** the soil-loss test,all soil sample filling areas belong to the runoff area,where the gentle-loss,strengthened-loss,and alleviated-loss parts are further divided.ΔR_(f) decreases from the gentle-loss part to the strengthened-loss part and then rebounds in the alleviated-loss part,and C_(i) increases and then decreases along the seepage *** relationship between ΔR_(f) and Ci is different with the boundary *** exponentially decreases with ΔR_(f) in the non-loss test and increases with ΔR_(f) generally in the soil-loss test.

关键词： Suffusion Permeability Experimental investigation Boundary effect Horizontal seepage