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Numerical Simulation of Independent Advance of Ore Breaking in the Non-pillar Sublevel Caving Method

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Journal of China University of Mining and Technology 2007年第2期17卷 295-300页

作者： ZHOU Chuan-bo YAO ying-kang GUO Liao-wu yin xiao-peng FAN xiao-feng SHANG ying Engineering College China University of Geosciences Wuhan Hubei 430074 China Ming Company of Wuhan Steel and Iron Unite Company Wuhan Hubei 430080 China

The mechanism of stress generation and propagation by detonation loading in five separate independent advance of ore breaking patterns is discussed in the paper. An elastic numerical model was developed using AN- SYS/LS-DYNA 3D Nonlinear Dynamic Finite Element Software. In this package ANSYS is the preprocessor and LS-DYNA is the postprocessor. Numerical models in the paper to actual were l：10 and the element mesh was dissected in scanning mode utilizing the symmetry characteristics of the numerical model. Five different advance rates were studied. Parameters, such as the time required to maximum stress, the action time of the available stress, the maximum velocity of the nodes, the stress penetration time, the magnitude of the stress peak and the time duration for high stress were numerically simulated. The 2.2 m advance appeared optimum from an analysis of the simulation results. The results from numerical simulation have been validated by tests with physical models.

关键词： non-pillar sublevel caving method independent advance of ore breaking numerical simulation model test

Construction of N-doped copper metal-organic frameworks for promoting photocatalytic carbon dioxide reduction to ethylene

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Science China Chemistry 2025年第2期68卷 601-609页

作者： Fan Guo Zong-Zheng He peng Wang xiao-Yu Zhang Hongjian Yu Qin-Chao Wang Wei-yin Sun School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Coordination Chemistry Institute State Key Laboratory of Coordination ChemistrySchool of Chemistry and Chemical EngineeringNanjing National Laboratory of MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China

Engineering nonmetallic atom-doped metal-organic framework(MOF)catalyst to promote C−C coupling and realize conversion of CO_(2) into C_(2 )multi-carbon hydrocarbon products is still ***,with 2-methylimidazole as a dopant of N element,an N-doped NH_(2)-CuBDC catalyst was obtained via a facile and simple stirring *** illumination,compared with catalytic CO_(2) reduction to C1 product of CO by original MOF,N-doped NH_(2)-CuBDC can motivate generation of C_(2)H_(4),which is difficult to achieve in photocatalytic system by MOF-based *** transfer rates of photo-generated charges have been expedited due to the high electron density around Cu catalytic sites after *** importantly,C–C coupling intermediate CO–CHO*was identified by in situ Fourier transform infrared spectroscopy during the catalytic CO_(2) reduction reaction process,which further indicates the presence of Cu–N sites in the NH_(2)-CuBDC can facilitate the formation of C2H_(4) *** work uncovers a new paradigm to design photocatalysts for enhancing the reduction of CO_(2) to C_(2) products.

关键词： metal-organic frameworks C-C coupling doping photocatalytic CO_(2) reduction Cu-based catalysts

Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology

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Neural Regeneration Research 2025年第9期20卷 2655-2666页

作者： Yiyang Qin Wenzhen Zhu Tingting Guo Yiran Zhang Tingting Xing peng yin Shihua Li xiao-Jiang Li Su Yang Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)Guangdong–HongKong–Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina

Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto *** mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy *** aggregates alter protein-protein interactions and compromise transcriptional *** this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic *** n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor *** down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor *** findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.

关键词： androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model neurodegeneration neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor

DKP-SLAM:A Visual SLAM for Dynamic Indoor Scenes Based on Object Detection and Region Probability

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Computers, Materials & Continua 2025年第1期82卷 1329-1347页

作者： Menglin yin Yong Qin Jiansheng peng College of Automation Guangxi University of Science and TechnologyLiuzhou545000China Department of Artificial Intelligence and Manufacturing Hechi UniversityHechi546300China Key Laboratory of AI and Information Processing Education Department of Guangxi Zhuang Autonomous RegionHechi546300China Guangxi Key Laboratory of Sericulture Ecology and Applied Intelligent Technology School of Chemistry and BioengineeringHechi UniversityHechi546300China

In dynamic scenarios,visual simultaneous localization and mapping(SLAM)algorithms often incorrectly incorporate dynamic points during camera pose computation,leading to reduced accuracy and *** paper presents a dynamic SLAM algorithm that leverages object detection and regional dynamic ***,a parallel thread employs the YOLOX object detectionmodel to gather 2D semantic information and compensate for missed ***,an improved K-means++clustering algorithm clusters bounding box regions,adaptively determining the threshold for extracting dynamic object contours as dynamic points *** process divides the image into low dynamic,suspicious dynamic,and high dynamic *** the tracking thread,the dynamic point removal module assigns dynamic probability weights to the feature points in these *** with geometric methods,it detects and removes the dynamic *** final evaluation on the public TUM RGB-D dataset shows that the proposed dynamic SLAM algorithm surpasses most existing SLAM algorithms,providing better pose estimation accuracy and robustness in dynamic environments.

关键词： Visual SLAM dynamic scene YOLOX K-means++clustering dynamic probability

Protein A immunoadsorption combined with rituximab in highly sensitized kidney transplant recipients

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Chinese Medical Journal 2009年第22期122卷 2752-2756页

作者： yin Hang HU xiao-peng LI xiao-bei LIU Hang WANG Wei REN Liang WANG Yong ZHANG xiao-dong Kidney Transplantation Program Department of Urology Beijing Chaoyang Hospital Capital Medical University Beijing 100020 China

Background The number of highly sensitized patients is rising, and sensitization can lead to renal transplant failure. The present study aimed to investigate the safety and efficacy of protein A immunoadsorption combined with rituximab （RTX） in highly sensitized recipients of kidney transplants.Methods Seven highly sensitized recipients of living-related renal transplants （4 men and 3 women, mean aged 42.5 years old （range 33-51）） were pretreated with this combination. Human leukocyte antigen （HLA） mismatch number was 2-5. Panel reactive antibody （PRA） of class Ⅰwas high in 2 cases and that of class Ⅱwas high in 1 case. All patients were pretreated with immunoadsorption 2-10 times. Immunoglobulin and PRA changes were monitored before and after absorption. The operation was conducted when PRA or immunoglobulin levels were at or below normal levels. Immunosuppressive drugs were provided 3-5 days before the operation, and one dose of RTX （375 mg/m^2） was infused with polyclonal antibody on the day of operation. Postoperative creatinine （Cr）, creatinine clearance rate （Ccr）, PRA ratio, and immunoglobulin changes were monitored.Results All 7 patients had good recovery without delayed graft function. Acute rejection occurred in 3 cases at postoperative days 8, 10, and 14, respectively. The Banff 07 biopsy grades were la in 1 case and lla C4d0 in 2 cases. Successful reversion was achieved after giving methylprednisolone or antithymocyte immunoglobulin ＋ cyclophosphamide. All patients were discharged with normal renal function, mean class Ⅰ PRA was 14% and mean class ⅡPRA was 35%. PRA was completely negative in 3 cases. Conclusion Protein A immunoadsorption combined with RTX can safely reduce the occurrence of humoral rejection in highly sensitized renal transplant recipients.

关键词： renal transplantation highly sensitized protein A immunoadsorption rituximab

Research on Stock Price Prediction Method Based on the GAN-LSTM-Attention Model

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Computers, Materials & Continua 2025年第1期82卷 609-625页

作者： peng Li Yanrui Wei Lili yin College of Computer Science and Technology Harbin University of Science and TechnologyHarbin150006China

Stock price prediction is a typical complex time series prediction problem characterized by dynamics,nonlinearity,and *** paper introduces a generative adversarial network model that incorporates an attention mechanism(GAN-LSTM-Attention)to improve the accuracy of stock price ***,the generator of this model combines the Long and Short-Term Memory Network(LSTM),the Attention Mechanism and,the Fully-Connected Layer,focusing on generating the predicted stock *** discriminator combines the Convolutional Neural Network(CNN)and the Fully-Connected Layer to discriminate between real stock prices and generated stock ***,to evaluate the practical application ability and generalization ability of the GAN-LSTM-Attention model,four representative stocks in the United States of America(USA)stock market,namely,Standard&Poor’s 500 Index stock,Apple Incorporatedstock,AdvancedMicroDevices Incorporatedstock,and Google Incorporated stock were selected for prediction experiments,and the prediction performance was comprehensively evaluated by using the three evaluation metrics,namely,mean absolute error(MAE),root mean square error(RMSE),and coefficient of determination(R2).Finally,the specific effects of the attention mechanism,convolutional layer,and fully-connected layer on the prediction performance of the model are systematically analyzed through ablation *** results of experiment show that the GAN-LSTM-Attention model exhibits excellent performance and robustness in stock price prediction.

关键词： Stock price prediction generative adversarial network attention mechanism time-series prediction

Recent progress on non-metallic carbon nitride for the photosynthesis of H_(2)O_(2):Mechanism,modification and in-situ applications

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Chinese Chemical Letters 2025年第1期36卷 165-175页

作者： Hao Lv Zhi Li peng yin Ping Wan Mingshan Zhu College of Environment and Climate Jinan UniversityGuangzhou 511443China Jiading Branch of Shanghai General Hospital Shanghai Jiao Tong University School of MedicineShanghai 201803China Department of Liver Surgery Ren Ji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China

Photocatalytic hydrogen peroxide(H_(2)O_(2))production has been considered as a promising strategy for H_(2)O_(2)synthesis due to its environmentally *** various photocatalysts,carbon nitride-based materials are excellent candidates for H_(2)O_(2)production because of their excellent visible-light response,low cost and high *** this review,we summarize in detail the research progress on the photocatalytic production of H_(2)O_(2)by carbon ***,we summarize the basic principles of photocatalysis and photocatalytic H_(2)O_(2)***,the classification and modification methods of carbonnitride-based materials are discussed,including morphology modulation,noble metal loading,defect control,heterojunction regulation,molecular structure engineering and elemental ***,the different in-situ applications of H_(2)O_(2)via photosynthesis were discussed,including disinfection and antibiotic resistant genes degradation,organic pollutants degradation,medical applications and fine chemical *** review brings great promise for in-situ H_(2)O_(2)photosynthesis,which is expected to serve as a key component in future applications.

关键词： Carbon nitride Hydrogen peroxide Photocatalysis Applications

DTD1 modulates synaptic efficacy by maintaining D-serine and D-aspartate homeostasis

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Science China(Life Sciences) 2025年第2期68卷 467-483页

作者： xiao Liu Chaojuan Yang Zhuoran Lin Jianing Li Bin yin Xuepei Lei Wei Han Boqin Qiang pengcheng Shu Chen Zhang xiaozhong peng State KeyLaboratoryofCommon Mechanism Research for Major Diseases Departmentof Biochemistry&Molecular BiologyMedicalPrimate Research CenterNeuroscienceCenterInstituteof Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing 100005China State Key Laboratory of Respiratory Health and Multimorbidity Beijing 100005China Institute of Laboratory Animal Sciences Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100021China School of Basic Medical Sciences Beijing Key Laboratory of Neural Regeneration and RepairCapital Medical UniversityBeijing 100069China Key Laboratoryof Biomechanics and Mechanobiology(Beihang University) Ministryof EducationBeijing AdvancedInnovation Center for Biomedical EngineeringSchoolof Engineering MedicineBeihang UniversityBeijing 100191China Chinese Institute for Brain Research Beijing 102206China

D-serine and D-aspartate are involved in N-methyl-D-aspartate receptor(NMDAR)-related physiological and pathological ***-t RNA deacylase 1(DTD1)may biochemically contribute to D-serine or D-aspartate ***,it is unclear thus far whether DTD1 regulates D-serine or D-aspartate content in neurobiological *** the present research,we found that DTD1 was essential to maintain the D-serine or D-aspartate homeostasis,which was consistent with the phenomenon that DTD1-deficiency resulted in changes in the quantity changes of functional NMDAR subunits in postsynaptic ***,DTD1 played a considerable role in regulating dendritic morphology and synaptic *** a consequence,DTD1 affected neurobiological events,including the synaptic strength of the CA3-to-CA1 circuit,dendritic spine density of hippocampal pyramidal neurons,and behavioral performance of mice in the Morris water *** findings highlight the important role of DTD1 in synaptic transmission,neuronal morphology,and spatial learning and memory and suggest an undisclosed mechanism of DTD1 that participates the regulation of D-serine or D-aspartate homeostasis in hippocampal neurons.

关键词： D-aminoacyl-tRNA deacylase 1 D-serine D-aspartate synaptic transmission neuronal morphology spatial learning and memory

Study of the Transport Behavior of Multispherical Proppant in Intersecting Fracture Based on Discrete Element Method

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Energy Engineering 2025年第1期122卷 185-201页

作者： Chengyong peng JianshuWu Mao Jiang Biao yin Yishan Lou CNOOC Research Institute Company Limited Beijing100028China School of Petroleum Engineering Yangtze UniversityWuhan430100China Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering(Yangtze University) Wuhan430100China

To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fractures,this study considered the combined impact of geological-engineering factors on *** reservoir production parameters and the discrete elementmethod,multispherical proppants were ***,a 3D fracture model,based on the specified conditions of the L block,employed coupled(Computational Fluid Dynamics)CFD-DEM(Discrete ElementMethod)for joint simulations to quantitatively analyze the transport and placement patterns of multispherical proppants in intersecting *** indicate that turbulent kinetic energy is an intrinsic factor affecting proppant ***,the efficiency of placement and migration distance of low-sphericity quartz sand constructed by the DEM in the main fracture are significantly reduced compared to spherical ceramic proppants,with a 27.7%decrease in the volume fraction of the fracture surface,subsequently affecting the placement concentration and damaging fracture *** to small-angle fractures,controlling artificial and natural fractures to expand at angles of 45°to 60°increases the effective support length by approximately 20.6%.During hydraulic fracturing of gas wells,ensuring the fracture support area and post-closure conductivity can be achieved by controlling the sphericity of proppants and adjusting the perforation direction to control the direction of artificial fractures.

关键词： Hydraulic fracturing discrete element method proppant sphericity CFD-DEM