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Sound & Vibration 2023年第1期57卷 97-117页

作者： Kanhua Su jian Wei Meng Li Hao Li Wenghao Da Lang zhang school of Petroleum Engineering Chongqing University of Science and TechnologyChongqing401331China

During the drilling process,stick-slip vibration of the drill string is mainly caused by the nonlinear friction gen-erated by the contact between the drill bit and the *** eliminate the fatigue wear of downhole drilling tools caused by stick-slip vibrations,the Fractional-Order Proportional-Integral-Derivative(FOPID)controller is used to suppress stick-slip vibrations in the drill *** the FOPID controller can effectively suppress the drill string stick-slip vibration,its structure isflexible and parameter setting is complicated,so it needs to use the cor-responding machine learning algorithm for parameter *** on the principle of torsional vibration,a simplified model of multi-degree-of-freedom drill string is established and its block diagram is *** continuous nonlinear friction generated by cutting rock is described by the LuGre friction *** adaptive learning strategy of genetic algorithm(GA),particle swarm optimization(PSO)and particle swarm optimization improved(IPSO)by arithmetic optimization(AOA)is used to optimize and adjust the controller parameters,and the drill string stick-slip vibration is suppressed to the greatest *** results show that:When slight drill string stick-slip vibration occurs,the FOPID controller optimized by machine learning algorithm has a good effect on suppressing drill string stick-slip ***,the FOPID controller cannot get the drill string system which has fallen into serious stick-slip vibration(stuck pipe)out of trouble,and the machine learning algorithm is required to mark a large amount of data on adjacent Wells to train the *** a reasonable range of drilling parameters(weight on bit/drive torque)in advance to avoid severe stick-slip vibration(stuck pipe)in the drill string system.

关键词： Stick-slip vibration machine learning fractional order proportional integral derivative(FOPID)control optimization algorithm

Evaluation of Er,Cr:YSGG laser for hard tissue ablation:an in vitro study

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Frontiers of Optoelectronics 2010年第2期3卷 163-168页

作者： Xianzeng zhang Shusen XIE Zhenlin ZHAN Haibin ZHAO jian GUO Qing YE Institute of Laser and Optoelectronics technology Fujian Provincial Key Laboratory for Photonics Technology Key Laboratory of Opto Electronic Science and Technology for Medicine of Ministry of Education Fujian Normal University Department of Otolaryngology Fujian Provincial Hospital Fujian Provincial Clinical College Fujian Medical University

The use of erbium,chromium:yttrium-scandium-gallium-garnet(Er,Cr:YSGG) laser with a wavelength of 2.78 μm for hard bone tissue ablation was evaluated. The surface morphology and microstructure changes of bone tissue treated with Er,Cr:YSGG were analyzed as compared to those treated with diamond *** influence of fluence on ablation rate and ablation efficiency as well as microstructure was also *** results show that Er,Cr:YSGG laser can perform bone perforation that is more fine and presented a lot of unique advantages compared to traditional methods. An approximately linear relationship was observed between the ablation rate/ablation efficiency and radiant *** the radiant exposure irradiated on bone tissue will produce stronger thermal injury around the crater and result in microstructure changing.

关键词： tissue ablation erbium chromium:yttrium-scandium-gallium-garnet (Er Cr:YSGG) laser bone evaluation technology

Diffusion tensor imaging reveals brain structure changes in dogs after spinal cord injury

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中国神经再生研究：英文版 2023年第1期18卷 176-182页

作者： Chang-Bin Liu De-Gang Yang Jun Li Chuan Qin Xin zhang Jun Liu Da-Peng Li jian-Jun Li Department of Rehabilitation Medicine Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Spinal and Neural Function Reconstruction China Rehabilitation Research CenterBeijingChina china Rehabilitation science Institute BeijingChina Department of Neurosurgery Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina

Based on the Wallerian degeneration in the spinal cord pathways,the changes in synaptic connections,and the spinal cord-related cellular responses that alter the cellular structure of the brain,we presumed that brain diffusion tensor imaging(DTI)parameters may change after spinal cord ***,the dynamic changes in DTI parameters remain *** established a Beagle dog model of T10 spinal cord contusion and performed DTI of the injured spinal *** found dynamic changes in DTI parameters in the cerebral peduncle,posterior limb of the internal capsule,pre-and postcentral gyri of the brain within 12 weeks after spinal cord *** then performed immunohistochemistry to detect the expression of neurofilament heavy polypeptide(axonal marker),glial fibrillary acidic protein(glial cell marker),and NeuN(neuronal marker).We found that these pathological changes were consistent with DTI parameter *** findings suggest that DTI can display brain structure changes after spinal cord injury.

关键词： spinal cord injury diffusion tensor imaging canines pathophysiology cerebrospinal structures corticospinal tract magnetic resonance imaging anisotropic fraction apparent dispersion coefficient

Morphine-3-glucuronide upregulates PD-L1 expression via TLR4 and promotes the immune escape of non-small cell lung cancer

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Cancer Biology & Medicine 2021年第1期18卷 155-171页

作者： Kaiyuan Wang jian Wang Ting Liu Wenwen Yu Nan Dong Chen zhang Wenbin Xia Feng Wei Lili Yang Xiubao Ren Department of Anesthesiology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Immunology and BiotherapyTianjin 300060China Department of Immunology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Immunology and BiotherapyTianjin 300060China Department of Cancer Biobank Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Immunology and BiotherapyTianjin 300060China Department of Biotherapy Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Immunology and BiotherapyTianjin 300060China

Objective:Patients with cancer pain are highly dependent on morphine analgesia,but studies have shown a negative correlation between morphine demand and patient *** long-term use of morphine may result in abnormally elevated serum morphine-3-glucuronide(M3G)***,the effects of M3G on tumor progression are worth ***:The effects of M3G on PD-L1 expressions in human non-small cell lung cancer(NSCLC)cell lines were first *** of TLR4 downstream pathways after M3G treatment was then determined by Western *** effects of M3G on human cytotoxic T lymphocytes(CTL)cytotoxicity and INF-γrelease was also ***,the LLC murine lung adenocarcinoma cell line were used to establish a murine lung cancer model,and the effects of M3G on tumor growth and metastasis were ***:M3G promoted the expressions of PD-L1 in the A549 and H1299 cell lines in a TLR4-dependent manner(P<0.05).M3G activated the PI3 K and the NFκB signaling pathways,and this effect was antagonized by a TLR4 pathway inhibitor.A PI3 K pathway inhibitor reversed the M3G-mediated PD-L1 upregulation.M3G inhibited the cytotoxicity of CTL on A549 cells and decreased the level of INF-γ.Repeated M3G intraperitoneal injections promoted LLC tumor growth and lung metastasis through the upregulation of tumor expressed PD-L1 and the reduction of CTL in the tumor ***:M3G specifically activated TLR4 in NSCLC cells and upregulated PD-L1 expression through the PI3 K signaling pathway,thereby inhibiting CTL cytotoxicity and finally promoting tumor immune escape.

关键词： Non-small cell lung cancer TLR4 PD-L1 morphine-3-glucuronide immune escape

集体林权制度下的安吉竹林经营认证模式探索与实践

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浙江林业科技 2024年第2期44卷 105-110页

作者：杨柳陆军郭飞燕张健沈诗音周熠浙江省林业科学研究院浙江杭州310023 浙江省安吉县竹产业协会浙江安吉313000

分析了安吉县林业生产与社会经济条件、竹林认证历程和认证模式,阐述了集体林权制度下安吉县毛竹股份合作社的组织形式、经营管理与“协会+合作社”模式开展竹林经营认证的运行机制,总结了“协会+合作社”模式开展竹林经营认证对提高竹... 详细信息

分析了安吉县林业生产与社会经济条件、竹林认证历程和认证模式,阐述了集体林权制度下安吉县毛竹股份合作社的组织形式、经营管理与“协会+合作社”模式开展竹林经营认证的运行机制,总结了“协会+合作社”模式开展竹林经营认证对提高竹林经济效益、促进竹林生态效益、加快农村城镇建设进程中的作用。提出在当前我国南方集体林权制度下引入新型竹林经营主体、推进竹林专业化经营、健全竹林经营管理体系,对开展竹林经营认证有积极作用。安吉县以“协会+合作社”开展竹林经营认证,对促进我国南方集体林权制度下的林业可持续发展具有示范作用。

关键词：集体林权制度竹林经营认证协会+合作社安吉

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透波材料及纤维增强透波复合材料的研究进展

现代化工 2024年第5期44卷 39-43页

作者：林道晴张琪凯侯振华吴佳奇支亚芳侯建华扬州大学环境科学与工程学院江苏扬州225000 北京新风航天装备有限公司北京100854 江西信达航科新材料科技有限公司江西南昌330599

介绍了石英陶瓷透波材料、氮化硅陶瓷透波材料、氧化硅纤维增强透波复合材料、氧化铝纤维增强透波复合材料、氮化硅纤维增强透波复合材料在力学性能、介电性能、烧蚀性能等各方面的综合性能,并详细综述了透波材料应用于航空航天领域的... 详细信息

介绍了石英陶瓷透波材料、氮化硅陶瓷透波材料、氧化硅纤维增强透波复合材料、氧化铝纤维增强透波复合材料、氮化硅纤维增强透波复合材料在力学性能、介电性能、烧蚀性能等各方面的综合性能,并详细综述了透波材料应用于航空航天领域的国内外研究成果及难点。

关键词：透波材料纤维增强透波复合材料航空航天力学性能

Deciphering the morpho–physiological traits for high yield potential in nitrogen efficient varieties(NEVs):A japonica rice case study

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Journal of Integrative Agriculture 2022年第4期21卷 947-963页

作者： ZHU Kuan-yu YAN Jia-qian SHEN Yong zhang Wei-yang XU Yun-ji WANG Zhi-qin YANG jian-chang jiangsu Key Laboratory of Crop Genetics and Physiology/jiangsu Key Laboratory of Crop Cultivation and Physiology/jiangsu Co-Innovation Center for Modern Production technology of Grain Crops Yangzhou UniversityYangzhou 225009P.R.China Joint International Research Laboratory of Agriculture and Agri-product Safety Ministry of EducationYangzhou UniversityYangzhou 225009P.R.China

The use of nitrogen(N)-efficient rice(Oryza sativa L.) varieties could reduce excessive N input without sacrificing yields. However, the plant traits associated with N-efficient rice varieties have not been fully defined or comprehensively explored. Here, three japonica N-efficient varieties(NEVs) and three japonica N-inefficient varieties(NIVs) of rice were grown in a paddy field under N omission(0 N, 0 kg N ha^(-1)) and normal N(NN, 180 or 200 kg N ha^(-1)) treatments. Results showed that NEVs exhibited higher grain yield and nitrogen use efficiency(NUE) than NIVs under both treatments, due to improved sink size and filled-grains percentage in the former which had higher root oxidation activity and greater root dry weight, root length and root diameter at panicle initiation(PI), as well as higher spikelet-leaf ratio and more productive tillers during the grain-filling stage. Compared with NIVs, NEVs also exhibited enhanced N translocation and dry matter accumulation after heading and improved flag leaf morpho-physiological traits, including greater leaf thickness and specific leaf weight and higher contents of ribulose^(-1),5-bisphosphate carboxylase/oxygenase, chlorophyll, nitrogen, and soluble sugars, leading to better photosynthetic performance. Additionally, NEVs had a better canopy structure, as reflected by a higher ratio of the extinction coefficient for effective leaf N to the light extinction coefficient, leading to enhanced canopy photosynthesis and dry matter accumulation. These improved agronomic and physiological traits were positively and significantly correlated with grain yield and internal NUE, which could be used to select and breed N-efficient rice varieties.

关键词： rice N-efficient varieties nitrogen use efficiency root morpho–physiological traits nitrogen translocation leaf morphology canopy structure

Artificial nerve graft constructed by coculture of activated Schwann cells and human hair keratin for repair of peripheral nerve defects

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Neural Regeneration Research 2023年第5期18卷 1118-1123页

作者： Han-Jun Qin Hang Li Jun-Ze Chen Kai-Rui zhang Xing-Qi Zhao jian-Qiang Qin Bin Yu Jun Yang Department of Orthopedics Nanfang HospitalSouthern Medical UniversityGuangdong Provincial Key Laboratory of Bone and Cartilage Regenerative MedicineNanfang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina Hebei Medical university ShijiazhuangHebei ProvinceChina Department of Orthopedics Baiyun Branch of Southern HospitalGuangzhouGuangdong ProvinceChina Department of Anatomy School of Basic Medical SciencesSouthern Medical UniversityGuangzhouGuangdong ProvinceChina Department of Orthopedics The 74th Group Military Hospital of PLAGuangzhouGuangdong ProvinceChina

Studies have shown that human hair keratin(HHK) has no antigenicity and excellent mechanical properties. Schwann cells, as unique glial cells in the peripheral nervous system, can be induced by interleukin-1β to secrete nerve growth factor, which promotes neural regeneration. Therefore, HHK with Schwann cells may be a more effective approach to repair nerve defects than HHK without Schwann cells. In this study, we established an artificial nerve graft by loading an HHK skeleton with activated Schwann cells. We found that the longitudinal HHK microfilament structure provided adhesion medium, space and direction for Schwann cells, and promoted Schwann cell growth and nerve fiber regeneration. In addition, interleukin-1β not only activates Schwann cells, but also strengthens their activity and increases the expression of nerve growth factors. Activated Schwann cells activate macrophages, and activated macrophages secrete interleukin-1β, which maintains the activity of Schwann cells. Thus, a beneficial cycle forms and promotes nerve repair. Furthermore, our studies have found that the newly constructed artificial nerve graft promotes the improvements in nerve conduction function and motor function in rats with sciatic nerve injury, and increases the expression of nerve injury repair factors fibroblast growth factor 2 and human transforming growth factor B receptor 2. These findings suggest that this artificial nerve graft effectively repairs peripheral nerve injury.

关键词： artificial nerve graft bioactive human hair keratin interleukin-1β macrophages nerve graft nerve growth factor nerve repair peripheral nervous injury Schwann cells

Ultrastructural studies of seed coat and cotyledon during rapeseed maturation

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Journal of Integrative Agriculture 2021年第5期20卷 1239-1249页

作者： CAO jian-bo HE Li-min Chinedu Charles NWAFOR QIN Li-hong zhang Chun-yu SONG Yan-tun HAO Rong Key Laboratory of Arable Land Conservation(Middle and Lower Reaches of Yangtse River) Ministry of Agriculture and Rural Affairs/Hubei Key Laboratory of Soil Environment and Pollution Remediation/College of Resources and EnvironmentHuazhong Agricultural UniversityWuhan 430070P.R.China Public Laboratory of Electron Microscopy Huazhong Agricultural UniversityWuhan 430070P.R.China National Key Laboratory of Crop Genetic Improvement/College of Plant science and technology Huazhong Agricultural UniversityWuhan 430070P.R.China

Brassica napus L.(***)is an important oil crop worldwide and it rapidly accumulates oil at late stage of seed ***,little is known about the cellular mechanism of oil accumulation and seed color changes during the late stage of rapeseed ***,we analyzed the ultrastructure of seed coat,aleurone and cotyledon in embryos of *** from 25 to 70 days after flowering(DAF).The pigments,which were deposited on the cell wall of palisade cells in seed coat,determined dark black color of *** chloroplasts degenerated into non-photosynthetic plastids which caused the green cotyledon to turn into *** chloroplasts in aleurone and cotyledon cells respectively degenerated into remnants without inner and outer envelope membranes and ecoplasts with intact inner and outer envelope *** 40 to 70 DAF,there were degraded chloroplasts without thylakoid,oil bodies contacting with plastids or protein bodies,big starch deposits of chloroplasts degrading into small particles then disappearing,and small endoplasmic reticulum(ER)in aleurone and cotyledon ***,there were decreases of chlorophyll content and dramatic increases of oil content in *** results suggested that the rapid oil accumulation was independent on the NADPH synthesized by photosynthesis of chloroplasts and probably utilized other sources of reductant,such as the oxidative pentose phosphate pathway during the late stage of rapeseed *** triacylglycerol assembly presumably utilizes the enzymes in the plastid,cytosol or oil body of cotyledon and aleurone cells.

关键词： rapeseed seed coat plastid development oil synthesis ultrastructure