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Chinese Journal of Mechanical Engineering 2024年第4期37卷 23-49页

作者： Heng Tang Jiaxiang Xu Bin Guo Yansong Xie Yalong sun Yanjun Lu yong Tang Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518000China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450001China

Titanium and its alloys have been widely applied in many biomedical fields because of its excellent mechanical properties,corrosion resistance and good ***,problems such as rejection,shedding and infection will occur after titanium alloy implantation due to the low biological activity of titanium alloy *** structures with specific functions,which can enhance osseointegration and antibacterial properties,are fabricated on the surface of titanium implants to improve the biological activity between the titanium implants and human *** paper presents a comprehensive review of recent developments and applications of surface functional structure in titanium and titanium alloy *** applications of surface functional structure on different titanium and titanium alloy implants are introduced,and their manufacturing technologies are summarized and ***,the fabrication of various surface functional structures used for titanium and titanium alloy implants is reviewed and analyzed in ***,the challenges affecting the development of surface functional structures applied in titanium and titanium alloy implants are outlined,and recommendations for future research are presented.

关键词： Surface functional structure Titanium implant Manufacturing technology Bioactivity

Study of inter-well interference in shale gas reservoirs by a robust production data analysis method based on deconvolution

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Petroleum Science 2024年第4期21卷 2502-2519页

作者： Wen-Chao Liu Cheng-Cheng Qiao Ping Wang Wen-Song Huang xiang-Wen Kong Yu-Ping sun He-Dong sun Yue-Peng Jia School of Civil and Resource Engineering University of Science and Technology Beijing PetroChina Research Institute of Petroleum Exploration and Development

In order to overcome the defects that the analysis of multi-well typical curves of shale gas reservoirs is rarely applied to engineering, this study proposes a robust production data analysis method based on deconvolution, which is used for multi-well inter-well interference research. In this study, a multi-well conceptual trilinear seepage model for multi-stage fractured horizontal wells was established, and its Laplace solutions under two different outer boundary conditions were obtained. Then, an improved pressure deconvolution algorithm was used to normalize the scattered production data. Furthermore, the typical curve fitting was carried out using the production data and the seepage model solution. Finally,some reservoir parameters and fracturing parameters were interpreted, and the intensity of inter-well interference was compared. The effectiveness of the method was verified by analyzing the production dynamic data of six shale gas wells in Duvernay area. The results showed that the fitting effect of typical curves was greatly improved due to the mutual restriction between deconvolution calculation parameter debugging and seepage model parameter debugging. Besides, by using the morphological characteristics of the log-log typical curves and the time corresponding to the intersection point of the log-log typical curves of two models under different outer boundary conditions, the strength of the interference between wells on the same well platform was well judged. This work can provide a reference for the optimization of well spacing and hydraulic fracturing measures for shale gas wells.

关键词： Shale gas Inter-well interference Deconvolution Production data analysis Typical curves Multi-stage fractured horizontal well

Notably Accelerated Nano-Bainite Transformation via Increasing Undissolved Carbides Content on GCr15Si1Mo Bearing Steel

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 703-712页

作者： Yan-Hui Wang Hua-Qiang sun Wen-Jing Feng Lei-Jie Zhao xiang Chen Qing-An Chen Hai-Tao sun Jian-Jun Wang Zhi-Nan Yang Key Laboratory of Intelligent Industrial Equipment Technology of Hebei Province School of Mechanical and Equipment EngineeringHebei University of EngineeringHandan056038China Collaborative Innovation Center for Modern Equipment Manufacturing of Jinan New Area Hebei University of EngineeringHandan056038China School of Materials Science and Engineering Tsinghua UniversityBeijing100084China Avic Shang da Superalloys Company Limited Xingtai054800China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004China

In this study, a high-carbon nano-bainitic GCr15Si1Mo bearing steel was investigated. Specifically, the effects of content and size of undissolved carbides on the microstructure and transformation kinetics of nano-bainite were analyzed. The results demonstrated that after prolonged austempering at low temperatures, the mixed microstructure composed of nano-bainite (NB), undissolved carbides (UC), and retained austenite (RA) was obtained in GCr15SiMo steel. When the experimental steel was austenitized at 900 ℃, the undissolved carbides gradually dissolved until reaching a stable state with increasing holding time. Furthermore, at the same austempering temperature, despite different volume fractions of undissolved carbides in the substrate, the volume fractions of nano-bainite in the final microstructures remained essentially the same. Moreover, the higher the content of undissolved carbides in steel, the faster the transformation rate of nano-bainite and the shorter the total transformation time.

关键词： Nano-bainite Undissolved carbides Bainitic transformation kinetics Carbon concentration

Improved Convolutional Neural Network for Traffic Scene Segmentation

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2691-2708页

作者： Fuliang Xu yong Luo Chuanlong sun Hong Zhao College of Mechanical and Electrical Engineering Qingdao UniversityQingdao266071China

In actual traffic scenarios,precise recognition of traffic participants,such as vehicles and pedestrians,is crucial for intelligent *** study proposes an improved algorithm built on Mask-RCNN to enhance the ability of autonomous driving systems to recognize traffic *** algorithmincorporates long and shortterm memory networks and the fused attention module(GSAM,GCT,and Spatial Attention Module)to enhance the algorithm’s capability to process both global and local ***,to increase the network’s initial operation stability,the original network activation function was replaced with Gaussian error linear *** were conducted using the publicly available Cityscapes *** the test results,it was observed that the revised algorithmoutperformed the original algorithmin terms of AP_(50),AP_(75),and othermetrics by 8.7%and 9.6%for target detection and 12.5%and 13.3%for segmentation.

关键词： Instance segmentation deep learning convolutional neural network attention mechanism

Immunostimulatory gene therapy combined with checkpoint blockade reshapes tumor microenvironment and enhances ovarian cancer immunotherapy

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Acta Pharmaceutica Sinica B 2024年第2期14卷 854-868页

作者： Yunzhu Lin xiang Wang Shi He Zhongxin Duan Yunchu Zhang Xiaodong sun Yuzhu Hu Yuanyuan Zhang Zhiyong Qian xiang Gao Zhirong Zhang Key Laboratory of Drug Targeting and Drug Delivery Systems Ministry of EducationWest China School of PharmacySichuan UniversityChengdu 610041China Department of Pharmacy Evidence-based Pharmacy CenterWest China Second University HospitalKey Laboratory of Birth Defects and Related Diseases of Women and ChildrenSichuan UniversityChengdu 610041China Department of Neurosurgery and Institute of Neurosurgery State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalWest China Medical SchoolSichuan University and Collaborative Innovation Center for BiotherapyChengdu 610041China Department of Radiation Oncology State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalWest China Medical SchoolSichuan University and Collaborative Innovation Center for BiotherapyChengdu 610041China West China School of Basic Medical Sciences&Forensic Medicine Sichuan UniversityChengdu 610041China

Immune evasion has made ovarian cancer notorious for its refractory features, making the development of immunotherapy highly appealing to ovarian cancer treatment. The immune-stimulating cytokine IL-12 exhibits excellent antitumor activities. However, IL-12 can induce IFN-γ release and subsequently upregulate PDL-1 expression on tumor cells. Therefore, the tumor-targeting folate-modified delivery system F-DPC is constructed for concurrent delivery of IL-12 encoding gene and small molecular PDL-1 inhibitor(i PDL-1) to reduce immune escape and boost anti-tumor immunity. The physicochemical characteristics, gene transfection efficiency of the F-DPC nanoparticles in ovarian cancer cells are analyzed. The immune-modulation effects of combination therapy on different immune cells are also studied. Results show that compared with non-folate-modified vector, folate-modified F-DPC can improve the targeting of ovarian cancer and enhance the transfection efficiency of p IL-12. The underlying anti-tumor mechanisms include the regulation of T cells proliferation and activation, NK activation,macrophage polarization and DC maturation. The F-DPC/p IL-12/i PDL-1 complexes have shown outstanding antitumor effects and low toxicity in peritoneal model of ovarian cancer in mice. Taken together, our work provides new insights into ovarian cancer immunotherapy. Novel F-DPC/p IL-12/i PDL-1 complexes are revealed to exert prominent anti-tumor effect by modulating tumor immune microenvironment and preventing immune escape and might be a promising treatment option for ovarian cancer treatment.

关键词： IL-12encodinggene Checkpointblocker Nanoparticles Targeted delivery Tumormicroenvironment Immune escape Ovarian cancer Immunotherapy

Synthesis,chemical bonding and reactivity of new medium-sized polyarsenides

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Chinese Chemical Letters 2024年第7期35卷 497-501页

作者： Xu-Hui Yue xiang-Wen Zhang Hui-Min He Lei Qiao Zhong-Ming sun State Key Laboratory of Element-Organic Chemistry Tianjin Key Lab for Institution Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Physics Institute of Computational and Applied PhysicsTaiyuan Normal UniversityJinzhong 030619China

Gaining an understanding of the growth mechanism from single atoms to clusters and bulk materials continues to present a ***,it is important to explore the evolving trends of clusters in the structure and properties during the size *** this work,we report the synthesis and characterization of two medium-sized chain-like polyarsenic anions.[As_(21)]^(3-)represents a trimeric example of polyarsenic anion assembled through oxidative coupling of As_(7)^(3-)*** anion As_(18)^(4-)included in[As_(18)MO_(2)(CO)_(8)]^(4-)is regarded as formed by two realgar-type As_(8)subunits connected by a dinuclear AsAs *** As_(18)cluster was previously predicted by theory,and this is the first time successfully synthesized using wet chemistry ***,small-sized polyarsenides As_(2)^(2-)and As_(10)^(2-)were found in compound[K(18-crown-6)]_(3)[As_(10)]_(0.5)[As_(4){Mo(CO)_(3)}_(2)]_(0.5)·*** these,the former exhibits coordination with metal ***-crystal X-ray diffraction combined with quantum chemical calculations revealed the formation of double bonded As_(2)^(2-)stabilized by metal carbonyl *** work demonstrates a novel synthetic approach for the preparation of new polyarsenides and highlights their intriguing bonding characteristics,laying the foundation for the synthesis of such compounds and paving the way for their potential applications.

关键词： Polyarsenide Zintl anions Chain-like cluster DFT calculations AdNDP

Machine learning-based radiomics score improves prognostic prediction accuracy of stage II/III gastric cancer: A multi-cohort study

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 345-356页

作者： Ying-Hao xiang Huan Mou Bo Qu Hui-Rong sun Department of General Surgery Lichuan People's HospitalEnshi 445400Hubei ProvinceChina

BACKGROUND Although accurately evaluating the overall survival(OS)of gastric cancer patients remains difficult,radiomics is considered an important option for studying *** To develop a robust and unbiased biomarker for predicting OS using machine learning and computed tomography(CT)image *** This study included 181 stage II/III gastric cancer patients,141 from Lichuan People's Hospital,and 40 from the Cancer Imaging Archive(TCIA).Primary tumors in the preoperative unenhanced CT images were outlined as regions of interest(ROI),and approximately 1700 radiomics features were extracted from each *** skeletal muscle index(SMI)and skeletal muscle density(SMD)were measured using CT images from the lower margin of the third lumbar *** the least absolute shrinkage and selection operator regression with 5-fold cross-validation,36 radiomics features were identified as important predictors,and the OS-associated CT image radiomics score(OACRS)was cal-culated for each patient using these important *** Patients with a high OACRS had a poorer prognosis than those with a low OACRS score(P<0.05)and those in the TCIA *** and multivariate analyses revealed that OACRS was a risk factor[RR=3.023(1.896-4.365),P<0.001]independent of SMI,SMD,and pathological ***,OACRS outperformed SMI and SMD and could improve OS prediction(P<0.05).CONCLUSION A novel biomarker based on machine learning and radiomics was developed that exhibited exceptional OS discrimination potential.

关键词： Radiomics Machine learning Gastric cancer Skeletal muscle density Skeletal muscle index

Anchoring heterometallic cluster on P-doped carbon nitride for efficient photocatalytic nitrogen fixation in water and air ambient

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Chinese Chemical Letters 2024年第4期35卷 176-180页

作者： Chao-Long Chen Rong Chen La-Sheng Long Lan-sun Zheng xiang-Jian Kong Collaborative Innovation Center of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Light-driven nitrogen fixation to produce ammonia is a green and economical technology of nitrogen reduction but is still quite challenging, especially in an air atmosphere without any sacrificial ***, we demonstrate efficient photocatalytic nitrogen fixation using water and air directly by loading lanthanide–transition metal(4f–3d) cluster NdCo_(3) on two-dimensional P-doped graphitic carbon nitrides(PCN) material surface. Benefiting from the increase in the number of nitrogen vacancies(NVs) and highly matched band gap structure and excellent hole trapping ability of clusters, the NdCo_(3)/PCN photocatalyst exhibits efficient nitrogen reduction activity with 371(in air) and 825 μmol h^(-1)g^(-1)(in pure nitrogen)without any sacrificial reagents. The introduction of potassium sulfate inhibits hydrogen production and promotes nitrogen reduction activation. This work suggests that anchoring precisely structured clusters on 2D materials may enhance photocatalytic nitrogen reduction under normal temperature and pressure.

关键词： Photocatalytic Nitrogen fixation 4f-3d Cluster Air atmosphere

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

Enhanced cyclic stability of partially disordered spinel cathodes through direct fluorination with gaseous fluorine

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Rare Metals 2024年第4期43卷 1635-1646页

作者： yong-Nian Ma Ling-Chen Kong Shao-Shan Chen yong Wang Li-Dong sun Cong Peng Meng-Meng Qin Yu Li Wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300072China Institute of Advanced Technology and Equipment Beijing University of Chemical TechnologyBeijing100029China

Spinel-type cathodes are considered an optimal substitute for conventional layered oxide cathodes owing to their use of inexpensive and earth-abundant manganese as the redox-active ***,the introduction of cation disorder can effectively suppress the detrimental two-phase reaction to realize high capacities in a wide voltage ***,the continuous capacity decay during cycles has hindered the widespread application of these cathode *** fluorides exhibit excellent electrochemical stability at high voltage;therefore,in this study,the direct F2 gas reaction with a partially disordered spinel cathode(Li_(1.6)Mn_(1.6)O_(3.7)F_(0.3,)LMOF1.6)was initially applied to investigate the impacts of fluorination on the surface structure and electrochemical *** inorganic fluorinated layer,mainly containing LiF,was distributed uniformly on the surface of LMOF1.6nanoparticles after fluorination for an appropriate time without the turbulence caused by the valency of manganese cation,which improved the capacity retention and rate capability by the suppression of structural damage,parasitic reaction,and cation *** LMOF1.6cathode fluorinated for 0.5 h exhibited a capacity of283.6 mAh·g^(-1)at 50 mA·g^(-1)and an enhanced capacity retention of 29.6%after 50 cycles in the voltage range of1.5-4.8 V,as compared to the pristine LMOF1.6 with only27.9%capacity retention.

关键词： Spinel-type cathodes Direct fluorination Capacity retention ability High rate capability