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Unmanned Ship Identification Based on Improved YOLOv8s Algorithm

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Computers, Materials & Continua 2024年第3期78卷 3071-3088页

作者： chun-Ming Wu Jin Lei Wu-Kai Liu Mei-Ling Ren Ling-Li ran Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology School of Electrical EngineeringNortheast Electric Power UniversityJilin132012China School of Biomedical Engineering Taiyuan University of TechnologyTaiyuan030600China

Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes an infrared ship detection model based on the improved YOLOv8 algorithm(R_YOLO).The algorithm incorporates the Efficient Multi-Scale Attention mechanism(EMA),the efficient Reparameterized Generalized-feature extraction module(CSPStage),the small target detection header,the Repulsion Loss function,and the context aggregation block(CABlock),which are designed to improve the model’s ability to detect targets at multiple scales and the speed of model inference.The algorithm is validated in detail on two vessel datasets.The comprehensive experimental results demonstrate that,in the infrared dataset,the YOLOv8s algorithm exhibits improvements in various performance metrics.Specifically,compared to the baseline algorithm,there is a 3.1%increase in mean average precision at a threshold of 0.5(mAP(0.5)),a 5.4%increase in recall rate,and a 2.2%increase in mAP(0.5:0.95).Simultaneously,while less than 5 times parameters,the mAP(0.5)and frames per second(FPS)exhibit an increase of 1.7%and more than 3 times,respectively,compared to the CAA_YOLO algorithm.Finally,the evaluation indexes on the visible light data set have shown an average improvement of 4.5%.

关键词： Unmanned ships R_YOLO EMA CSPStage YOLOv8s

One-step conversion of methane and formaldehyde to ethanol over SA-FLP dual-active-site catalysts: A DFT study

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Chinese Chemical Letters 2024年第4期35卷 544-548页

作者： Tao Ban Xi-Yang Yu Hai-Kuo Tian Zheng-Qing Huang chun-ran Chang Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an 710049China Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization School of Chemistry and Chemical EngineeringYulin UniversityYulin 719000China

One-step conversion of methane and formaldehyde into ethanol is a 100% atom-efficient process for carbon resources utilization and environment protection but still faces eminent challenges due to the lacking of efficient catalysts. Therefore, developing active and stable catalysts is crucial for the co-conversion of methane and formaldehyde. Herein, twelve kinds of “Single-Atom”-“Frustrated Lewis Pair”(SA-FLP)dual-active-site catalysts are designed for the direct conversion of methane and formaldehyde to ethanol based on density functional theory(DFT) calculations and microkinetic simulations. The results show that the SA-FLP dual active sites can simultaneously activate methane at the SA site and activate formaldehyde at the FLP site. Among the twelve designed SA-FLP catalysts, Fe1-FLP shows the best performance in the co-conversion of methane and formaldehyde to ethanol with the rate-determining barrier of 1.15 e V.Ethanol is proved as the main product with the turnover frequency of 1.32 × 10^(-4)s^(-1)at 573 K and 3 bar.This work provides a universal strategy to design dual active sites on metal oxide materials and offers new insights into the effective conversion of methane and formaldehyde to desired C_(2) chemicals.

关键词： Single-atom Frustrated Lewis pairs Methane conversion Dual active sites Ethanol synthesis

Sinomenine increases osteogenesis in mice with ovariectomyinduced bone loss by modulating autophagy

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World Journal of Stem Cells 2024年第5期16卷 486-498页

作者： Hai-Xiang Xiao Lei Yu Yu Xia Kai Chen Wen-Ming Li Gao-ran Ge Wei Zhang Qing Zhang Hong-Tao Zhang De-chun Geng Department of Orthopedics The Fourth Affiliated Hospital of Soochow UniversitySuzhou Dushu Lake HospitalMedical Centre of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina Department of Orthopedics Jingjiang People’s Hospital Affiliated to Yangzhou UniversityJingjiang 214500Jiangsu ProvinceChina Department of Orthopedics The First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina Department of Orthopedics Hai’an People’s HospitalHai’an 226600Jiangsu ProvinceChina Department of Orthopedics The Affiliated Huai’an Hospital of Xuzhou Medical UniversityHuai’an Second People’s HospitalXuzhou 223002Jiangsu ProvinceChina Department of Orthopaedics The First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

BACKGROUND A decreased autophagic capacity of bone marrow mesenchymal stromal cells(BMSCs)has been suggested to be an important cause of decreased osteogenic differentiation.A pharmacological increase in autophagy of BMSCs is a potential therapeutic option to increase osteoblast viability and ameliorate osteoporosis.AIM To explore the effects of sinomenine(SIN)on the osteogenic differentiation of BMSCs and the underlying mechanisms.METHODS For in vitro experiments,BMSCs were extracted from sham-treated mice and ovariectomized mice,and the levels of autophagy markers and osteogenic differentiation were examined after treatment with the appropriate concen-trations of SIN and the autophagy inhibitor 3-methyladenine.In vivo,the therapeutic effect of SIN was verified by establishing an ovariectomy-induced mouse model and by morphological and histological assays of the mouse femur.RESULTS SIN reduced the levels of AKT and mammalian target of the rapamycin(mTOR)phosphorylation in the phosphatidylinositol 3-kinase(PI3K)/AKT/mTOR signaling pathway,inhibited mTOR activity,and increased autophagy ability of BMSCs,thereby promoting the osteogenic differentiation of BMSCs and effectively alleviating bone loss in ovariectomized mice in vivo.CONCLUSION The Chinese medicine SIN has potential for the treatment of various types of osteoporosis,bone homeostasis disorders,and autophagy-related diseases.

关键词： Sinomenine Osteogenesis Autophagy Ovariectomy Osteoporosis

Impact of fluorine on crystal-melt separation in high-silica magma: Insights from muscovite in the Ramba leucogranite of Tethyan Himalaya

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Journal of Earth Science 2024年

作者： Li-ran Chen Wang-chun Xu Lian-Xun Wang Hong-Fei Zhang Wuhan State Key Laboratory of Geological Processes and Mineral Resources and School of Earth Sciences China University of Geosciences

The process of crystal-melt separation in the high-silica magmatic mush is still a subject of debate. To explore the process， we conducted a detailed study of Late Miocene leucogranites (SiO2＞70 wt.%) in the Ramba Dome of the Tethyan Himalaya， focusing on the genesis and fluorine content of muscovite. The Ramba leucogranites consist of two-mica granite with minor garnet-bearing granite. Large and euhedral muscovites are found in both types of granite exhibiting different geochemical features. The muscovites from the two-mica granites exhibit lower F (mean value: ～0.41–0.43 wt.%)， FeO (mean value: ～1.75–1.81 wt.%)， but higher TiO2(mean value: ～0.61–0.73 wt.%) contents compared to those from the garnet-bearing granites (mean F value: ～0.72%; mean FeO value: 2.48 wt.%; mean TiO2value: ～0.23 wt.%). According to geochemical criteria， we categorized the muscovites from the two-mica granite as two groups: (1) crystallized from the early magma， and (2) formed from interstitial residual melt. In comparison， the muscovite from the garnet-bearing granite was likely crystallized from residual melt extracted from the same magmatic reservoir which underwent a higher degree of evolution. Accordingly， the two-mica granite represents the residual crystal mush consisting of early crystals crystallized from magma and trapped interstitial residual melt， while the garnet-bearing granite represents the aggregation of extracted residual melt. We examined the possibility of crystal-melt separation by estimating the variation of fluorine content and viscosity between the early magma and residual melt. Our results indicate a notable disparity in fluorine content between the residual melt (mean value: ～4364 ppm) and the early magma (mean value: ～2033 ppm). As a result， the estimated viscosity experiences a reduction from 106.52Pa s for the early magma to 105.87Pa s for the residual melt. The fluorine enrichment could have played a critical role in decreasing melt viscosity and initiating crystal-melt separation. Our result supports the cry

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The role of innate immunity in diabetic nephropathy and their therapeutic consequences

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Journal of Pharmaceutical Analysis 2024年第1期14卷 39-51页

作者： Min Yang chun Zhang Department of Nephrology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China

Diabetic nephropathy (DN) is an enduring condition that leads to inflammation and affects a substantial number of individuals with diabetes worldwide. A gradual reduction in glomerular filtration and emergence of proteins in the urine are typical aspects of DN, ultimately resulting in renal failure. Mounting evidence suggests that immunological and inflammatory factors are crucial for the development of DN. Therefore, the activation of innate immunity by resident renal and immune cells is critical for initiating and perpetuating inflammation. Toll-like receptors (TLRs) are an important group of receptors that identify patterns and activate immune responses and inflammation. Meanwhile, inflammatory responses in the liver, pancreatic islets, and kidneys involve inflammasomes and chemokines that generate pro-inflammatory cytokines. Moreover, the activation of the complement cascade can be triggered by glycated proteins. This review highlights recent findings elucidating how the innate immune system contributes to tissue fibrosis and organ dysfunction, ultimately leading to renal failure. This review also discusses innovative approaches that can be utilized to modulate the innate immune responses in DN for therapeutic purposes.

关键词： Innate immunity Diabetic nephropathy Inflammation Toll-like receptor Inflammasomes

Advancements in machine learning for material design and process optimization in the field of additive manufacturing

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China Foundry 2024年第2期21卷 101-115页

作者： Hao-ran Zhou Hao Yang Huai-qian Li Ying-chun Ma Sen Yu Jian shi Jing-chang Cheng Peng Gao Bo Yu Zhi-quan Miao Yan-peng Wei National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China School of Materials Science and Engineering Nanyang Technological University639798Singapore

Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric challenges.However,the development of additive manufacturing process is constrained by issues like unclear fundamental principles,complex experimental cycles,and high costs.Machine learning,as a novel artificial intelligence technology,has the potential to deeply engage in the development of additive manufacturing process,assisting engineers in learning and developing new techniques.This paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing,particularly in model design and process development.Firstly,it introduces the background and significance of machine learning-assisted design in additive manufacturing process.It then further delves into the application of machine learning in additive manufacturing,focusing on model design and process guidance.Finally,it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing.

关键词： additive manufacturing machine learning material design process optimization intersection of disciplines embedded machine learning

Time-resolved ultra-small-angle X-ray scattering beamline(BL10U1)at SSRF

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Nuclear Science and Techniques 2024年第2期35卷 6-19页

作者： Wen-Qiang Hua chun-Ming Yang Ping Zhou Feng Tian Jin-You Lin Yu-Zhu Wang Xiao-Yun Li Xia-ran Miao chun-Xia Hong Qiu-Shi Huang Xin-Tong Zhao Yong-Feng Men Jie Wang Xing-Yu Gao Xiu-Hong Li Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Key Laboratory of Advanced Micro Structural Materials MOEInstitute of Precision Optical EngineeringSchool of Physics Science and EngineeringTongji UniversityShanghai 200092China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The construction of a new beamline,BL10U1,was completed at the Shanghai synchrotron radiation facility in 2020.This multipurpose beamline was designed to provide X-ray scattering techniques such as ultra-small-angle X-ray scattering(USAXS),small-angle X-ray scattering(SAXS),wide-angle X-ray scattering,and microfocus SAXS(μSAXS)for a broad user community.To realize fast time-resolved USAXS experiments,the beamline adopted an in-vacuum undulator with a total length of 1.6 m as the photon source.An in-house cryogenic-cooled double multilayer monochromator was installed to deliver a photon flux of approximately 10^(13) photons/s at a photon energy of 10 keV.The three-year successful operation of this beamline demonstrated that the monochromator operated smoothly,as expected.BL10U1 has three end stations in succession:USAXS end station,μSAXS end station,and end station for industrial applications.The minimum scattering vector q~0.0042 nm^(-1) at 10 keV can be achieved at the USAXS end station equipped with a 28 m-long and 1.8 m-diameter vacuum flight tube.At theμSAXS end station,a beam spot of less than 10×8μm was achieved for micro-SAXS experiments.In contrast,in situ experimental instruments up to 5 m high and 8 m wide can be mounted at the industrial application end station,which offers industrial scientists the opportunity to use their large industrial equipment.BL10U1 opens up a new capability to investigate phenomena such as non-equilibrium and dynamic processes of materials with a wide length scale from angstroms to micrometers with millisecond time resolution.In this paper,we also report beamline design considerations and commissioning results.

关键词： Synchrotron radiation Ultra-small-angle X-ray scattering Micro small-angle X-ray scattering USAXS Time resolved μSAXS

Extracellular vesicles derived from mesenchymal stem cells mediate extracellular matrix remodeling in osteoarthritis through the transport of microRNA-29a

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World Journal of Stem Cells 2024年第2期16卷 191-206页

作者： Fan Yang Wan-Qi Xiong Chen-Zhi Li Ming-Jian Wu Xiu-Zhi Zhang chun-Xiao ran Zhen-Hao Li Yan Cui Bao-Yi Liu De-Wei Zhao Department of Orthopedics Affiliated Zhongshan Hospital of Dalian UniversityDalian 116001Liaoning ProvinceChina

BACKGROUND Knee osteoarthritis(KOA)is a common orthopedic condition with an uncertain etiology,possibly involving genetics and biomechanics.Factors like changes in chondrocyte microenvironment,oxidative stress,inflammation,and immune responses affect KOA development.Early-stage treatment options primarily target symptom relief.Mesenchymal stem cells(MSCs)show promise for treatment,despite challenges.Recent research highlights microRNAs(miRNAs)within MSC-released extracellular vesicles that can potentially promote cartilage regeneration and hinder KOA progression.This suggests exosomes(Exos)as a promising avenue for future treatment.While these findings emphasize the need for effective KOA progression management,further safety and efficacy validation for Exos is essential.AIM To explore miR-29a’s role in KOA,we’ll create miR-29a-loaded vesicles,testing for early treatment in rat models.METHODS Extraction of bone marrow MSC-derived extracellular vesicles,preparation of engineered vesicles loaded with miR-29a using ultrasonication,and identification using quantitative reverse transcription polymerase chain reaction;after establi-shing a rat model of KOA,rats were randomly divided into three groups:Blank control group injected with saline,normal extracellular vesicle group injected with normal extracellular vesicle suspension,and engineered extrace-llular vesicle group injected with engineered extracellular vesicle suspension.The three groups evaluation,histological detection,and immunohistochemical detection to compare and evaluate the progress of various forms of arthritis.RESULTS General behavioral observation results showed that the extracellular vesicle group and engineered extracellular vesicle group had better performance in all four indicators of pain,gait,joint mobility,and swelling compared to the blank control group.Additionally,the engineered extracellular vesicle group had better pain relief at 4 wk and better knee joint mobility at 8 wk compared to the normal extracellular vesicle group.Imaging examinat

关键词： Exosomes Osteoarthritis Mesenchymal stem cells MicroRNA-29a Intra-articular injection

Design and pricing of maintenance service contract based on Nash non-cooperative game approach

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Journal of Systems Engineering and Electronics 2024年第1期35卷 118-129页

作者： SU chun HUANG Kui School of Mechanical Engineering Southeast UniversityNanjing 211189China

Nowadays manufacturers are facing fierce challenge.Apart from the products,providing customers with multiple maintenance options in the service contract becomes more popular,since it can help to improve customer satisfaction,and ultimately promote sales and maximize profit for the manufacturer.By considering the combinations of corrective maintenance and preventive maintenance,totally three types of maintenance service contracts are designed.Moreover,attractive incentive and penalty mechanisms are adopted in the contracts.On this basis,Nash non-cooperative game is applied to analyze the revenue for both the manufacturer and customers,and so as to optimize the pricing mechanism of maintenance service contract and achieve a win-win situation.Numerical experiments are conducted.The results show that by taking into account the incentive and penalty mechanisms,the revenue can be improved for both the customers and manufacturer.Moreover,with the increase of repair rate and improvement factor in the preventive maintenance,the revenue will increase gradually for both the parties.

关键词： maintenance service contract Nash game incentive and penalty mechanism corrective maintenance preventive maintenance