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Preliminary studies on the molecular mechanism of intramuscular fat deposition in the longest dorsal muscle of sheep

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BMC GENOMICS 2024年第1期25卷 592页

作者： Shao, xuwen Lu, Xintan Sun, Xinming Jiang, Huaizhi chen, Yang Jilin Agr Univ Coll Anim Sci & Technol Changchun 130118 Peoples R China Minist Agr & Rural Affairs Key Lab Livestock & Poultry Resources Sheep & Goat Changchun Peoples R China

Background Intramuscular fat content is an important index reflecting the quality of mutton, which directly affects the flavor and tenderness of mutton. Livestock and poultry intramuscular fat content is influenced by genetics, nutritional level, and environmental factors. Key regulatory factors play a crucial role in intramuscular fat deposition. However, there is a limited amount of research on the identification and function of key genes involved in intramuscular fat content deposition specifically in sheep. Results Histological differences in the longest dorsal muscle of the small-tailed frigid sheep increased in diameter and decreased in several muscle fibers with increasing monthly age;The intramuscular fat content of the longest dorsal muscle of the small-tailed cold sheep varied with age, with a minimum of 1 month of age, a maximum of 6 months of age, and a minimum of 12 months of age. Transcriptomic sequencing and bioinformatics analysis revealed a large number of differential genes in the longest dorsal muscles of little-tailed billy goats of different months of age, which were enriched in multiple GO entries and KEGG pathways. Among them, the pathway associated with intramuscular fat was the AMPK signaling pathway, and the related genes were PPARGC1A and ADIPOQ;Immunohistochemical studies showed that PPARGC1A and ADIPOQ proteins were expressed in connective tissues, cell membranes, and, to a lesser extent, the cytoplasm of the longest dorsal muscle of the little-tailed frigid sheep;Real-time PCR and Western Blot validation showed that PPARGC1A and ADIPOQ were both expressed in the longest dorsal muscle of the little-tailed frigid sheep at different ages, and there were age differences in the amount of expression. The ADIPOQ gene was negatively correlated with the intramuscular fat content of the longest dorsal muscle, and the PPARGC1A gene was positively correlated with the intramuscular fat content of the longest dorsal muscle;As inferred from the above

关键词： Small-tailed frigid sheep Longest dorsal muscle Intramuscular fat Growth and development Transcriptomics

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Positioning accuracy improvement method of industrial robot based on laser tracking measurement

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Measurement: Sensors 2021年 18卷

作者： Hongfei Zu xuwen chen Zhangwei chen Zhirong Wang Xiang Zhang School of Mechanical Engineering & Automation Zhejiang Sci-Tech University China Zhejiang Premax Technology Co. Ltd Ningbo 315048 China State Key Laboratory of Fluid Power and Mechatronics Systems Zhejiang University China Hangzhou ECON Technology Co. Ltd Hangzhou 310015 China School of Computer Science Hangzhou Dianzi University Hangzhou 310000 China

Positioning accuracy is of great significance for industrial robots in high-end industries. In addition to kinematic parameter errors, there are also some dynamic parameter errors, which are nonlinear. This paper proposes a novel method to improve the positioning accuracy of industrial robot, which takes both kinematics and dynamics parameter errors into account. Firstly, the method uses improved Denavit-Hartenberg (DH) model to establish kinematics model and identifies the geometric errors. Then, the deformation of the joint is analysed, and the angle deviation of each joint due to the end load is compensated. Finally, the accuracy improvement experiment is carried out on 6R robot. The experimental results show that the method is very effective.

关键词： DH model Joint deformation Positioning accuracy Laser tracking measurement

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Dynamic simulation on multilevel coupled vibration of a naval gun under foundation motion excitation of ship

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ALEXANDRIA ENGINEERING JOURNAL 2024年 107卷 347-358页

作者： chen, Yu Xie, Mingliang Zou, Xiaofeng Liu, Jinfeng Yan, Dejun Jing, xuwen Jiangsu Univ Sci & Technol Sch Mech & Engn Zhenjiang 212100 Peoples R China CSSC Huangpu Wenchong Shipbldg Co Ltd Guangdong Prov Key Lab Adv Welding Technol Ships Guangzhou 510720 Peoples R China

To study the multilevel coupled vibration of a naval gun under the foundation motion excitation of the ship, a mechanical-electrical-hydraulic coupled dynamic model of the naval gun including the follow-up systems' influence was established. The subprogram for calculating the ship foundation motion was written by the harmonic superposition method, and the motion in the 3 and 5-scale sea waves was reconstructed, respectively. Based on the multidisciplinary simulation, the transmission characteristics of the ship's foundation motion excitation along the naval gun and the influence of the tooth arc arrangement on the stabilization accuracy of the naval gun are analyzed. The results show that: the foundation motion excitation of the ship will aggravate the imbalance of the contact forces at the left and right trunnions of the cradle. A bilateral symmetrical arrangement scheme of the tooth arcs can reduce the contact forces' imbalance at the trunnions and reduce the adverse influence on the stabilization accuracy of the naval gun. The relevant research provides theoretical support and technical guidance for the structural design or verification of the naval gun.

关键词： Naval gun Wave excitation Follow-up system Co-simulation Stabilization accuracy

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Cam Profile Design of Low-Speed Marine Diesel Engine Based on the Grey Theory 5

Cam Profile Design of Low-Speed Marine Diesel Engine Based o...

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2023 5th International Conference on Advanced Materials and Ecological Environment, AMEE 2023

作者： Xu, Zhen chen, Jianzhi Jing, xuwen School of Mechanical Engineering Jiangsu University of Science and Technology Jiangsu Zhenjiang212003 China

The camshaft profile is one of the important parameters of the engine, the reasonableness or otherwise of its design directly influences the engine's power output, fuel consumption, emissions, noise and reliability. However, most existing cam profile optimization designs are based on the basic software operation, profile parameter selection and tuning lack a scientific theoretical basis. In order to address this issue, this study establishes a single valve kinematic model of the gas delivery mechanism of diesel engines by using the AVL-EXCITE Timing Drive, and performs a model-based multinomial kinematic acceleration cam profile design. Subsequently, an orthogonal design method is employed to obtain the parameter combinations that can satisfy the dynamic requirements. The research investigates the influence of cam profile design parameters (C 4, p, q, r, and s) on valve fullness, maximum jerk, cam contact stress, and valve seating force through a systematic study. Lastly, based on the grey correlation theory, a thorough analysis of the performance indices of cams with different profile parameter combinations is conducted. The optimization problem of the profile parameters with multiple performance indicators is transformed into a single-objective grey relational optimization problem, resulting in the optimal cam profile parameter combination of C4 =0.1, p=14, q=20, r=28 and s=36. The optimal method proposed in the paper is straightforward to implement and is applicable to the optimum design of cam profiles of the engine, which is of great importance for the optimal design of cam fabrication processes. © Published under licence by IOP Publishing Ltd.

关键词： Cams

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翼状胬肉切除术联合角膜缘干细胞移植术对原发性翼状胬肉患者视力恢复的影响及安全性

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中外医疗 2025年第8期44卷 57-60页

作者：张诚陈旭文郭美珍福清东南眼科医院眼科

目的研究翼状胬肉切除术（excision of pterygium, EOP）联合角膜缘干细胞移植（corneal limbal stem cell transplantation, CLSCT）术对原发性翼状胬肉患者视力恢复的影响及安全性。方法随机选取2023年2月—2024年2月经福清东南眼... 详细信息

目的研究翼状胬肉切除术（excision of pterygium, EOP）联合角膜缘干细胞移植（corneal limbal stem cell transplantation, CLSCT）术对原发性翼状胬肉患者视力恢复的影响及安全性。方法随机选取2023年2月—2024年2月经福清东南眼科医院确诊为原发性翼状胬肉的110例患者作为研究对象，依据不同手术方法分为对照组和观察组，各55例。对照组仅接受EOP治疗，观察组接受EOP联合CLSCT术治疗，比较两组的手术疗效、视力状况、泪膜功能以及手术安全性。结果观察组手术总有效率为94.55%（52/55），高于对照组的81.82%（45/55），差异有统计学意义（χ2=4.274,P=0.038）。术后3个月，观察组角膜屈光度小于对照组，裸眼视力高于对照组，差异均有统计学意义（P均<0.05）。术后3个月，观察组泪膜功能指标优于对照组，差异有统计学意义（P<0.05）。两组手术并发症总发生率对比，差异无统计学意义（P>0.05）。结论对原发性翼状胬肉患者施以EOP联合CLSCT术式治疗有确切效果，有利于泪膜功能及视力状况的恢复，并且手术的安全性良好。

关键词：原发性翼状胬肉翼状胬肉切除术角膜缘干细胞移植术视力恢复安全性

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Influence of initial microstructure on surface integrity of ultrasonic impacting strengthened 34CrNi3MoA steel crankshaft

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JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY 2024年第2期38卷 683-689页

作者： chen, Jianzhi Zhuge, Yunhai Ren, Hailiang Jing, xuwen Wang, Yan Li, Guochao Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang 212003 Peoples R China Henan Diesel Engine Heavy Ind Co Ltd Luoyang 471039 Peoples R China

The ultrasonic impacting process was carried out on the fillet of 34CrNi3MoA steel crankshaft treated by quenching and tempering, medium frequency quenching and gas nitriding respectively, and the variations of surface integrity of crankshaft were analyzed. The results show that the Ra of fillet can be decreased to below 0.2 mu m after the ultrasonic impacting. The ultrasonic impacted crankshaft with initial process of gas nitriding has the highest hardness but the lowest hardness increase rate due to its high deformation resistance of nitriding layer. The ultrasonic impacting can transfer the tensile residual stress to the compressive residual stress on the fillet, the specimens with initial process of gas nitriding exhibit the highest compressive residual stress of -412.17 MPa. The fatigue performance model of the crankshaft was established based on Basquin and Goodman equations, the crankshaft treated by gas nitriding and ultrasonic impacting is supposed to have the highest fatigue limit.

关键词： 34CrNi3MoA steel Crankshaft Fatigue performance Ultrasonic impacting Surface integrity

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Effect of Cr on wear resistance and mechanism of preset-powder laser cladding T15 alloy steel coating

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JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T 2024年 29卷 4991-4999页

作者： Shang, Fanmin Xu, Zhen chen, Jianzhi chen, Liangyu Lu, Sheng Wang, Shanlin Jing, xuwen Dubovyi, Oleksandr Jiangsu Univ Sci & Technol Sch Mat Sci & Engn Zhenjiang 212003 Peoples R China Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang 212003 Peoples R China Nanchang Hangkong Univ Jiangxi Key Lab Forming & Joining Technol Aerosp C Nanchang 330063 Peoples R China Admiral Makarov Natl Univ Shipbldg Sch Mat Sci & Engn UA-54025 Mvkolaviv Ukraine

Remanufacturing worn parts by the laser cladding process has wide prospect. To repair the worn camshafts, the T15 alloy steel coatings with different content of Cr were fabricated by the preset-powder laser cladding (PPLC). The effect of Cr content (3, 6, 9 and 12 wt%) on the microstructure and the wear resistance of T15 alloy steel coatings was investigated from the aspects of solution element, grain size and phase composition. The results indicate that the microstructure of the coatings is composed of martensite, retained austenite (RA) and eutectic boron-carbides. The content of martensite increases first and then decreases, the content of RA decreases and the content of eutectic boron-carbides increases with the increment of Cr content. The wear resistance increased first and then decreased with the increment of Cr content, the T15 alloy steel coating with the 9 wt% Cr has the hardness of 880 HV0.2, exhibiting the lowest wear rate (2.85 x 10-8 mm3/N & sdot;mm). A modified relationship between the wear rate and the Cr content is built by the nonlinear fitting method based on the classical Archard wear mode, the fitted results showed that the T15 alloy steel coating with 10.04 wt% Cr content has the highest wear resistance, which can provide a reference for the composition optimization of high speed steel with desired wear resistance.

关键词： T15 alloy steel Cr Preset -powder laser cladding Wear resistance

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室外长距离照明配电接地型式及电击防护研究

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建筑电气 2020年第7期39卷 49-58页

作者：陈天铭陈旭文福州市规划设计研究院福州市350108

通过对室外不具备等电位联结条件的道路及景观照明设施电击事故的调查,得出应按潮湿环境要求对室外照明设施进行电击防护设计;同时为了使接地故障电压在安全限值以内,对室外景观及道路照明采用不同接地型式的优点和缺陷进行定性和定量... 详细信息

通过对室外不具备等电位联结条件的道路及景观照明设施电击事故的调查,得出应按潮湿环境要求对室外照明设施进行电击防护设计;同时为了使接地故障电压在安全限值以内,对室外景观及道路照明采用不同接地型式的优点和缺陷进行定性和定量地剖析比较,给出了满足电击防护安全要求的接地型式及相关其他安全防护措施。

关键词：电击防护 TN接地系统 TT接地系统漏电监测探测器长距离室外景观照明室外道路照明剩余电流断路器等电位联结

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Lithological Unit Classification Based on Geological Knowledge-Guided Deep Learning Framework for Optical Stereo Mapping Satellite Imagery

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IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 2023年 61卷 1页

作者： Zhou, Gaodian chen, Weitao Qin, xuwen Li, Jun Wang, Lizhe China Univ Geosci Fac Comp Sci Minist Educ Wuhan 430074 Peoples R China China Univ Geosci Minist Educ Key Lab Geol Survey & Evaluat Wuhan 430074 Peoples R China

Lithological unit classification (LUC) refers to the classification of different types of rocks within an area, and it has been widely used in many fields, such as resource surveys and infrastructure planning. However, traditional field surveys require a lot of resources and time. Since remote sensing technology can rapidly acquire information without regional limitations, many researchers have focused on classifying lithological units with remote sensing images. However, in an area covered by vegetation, the beneficial information directly provided by remote sensing images is limited. Moreover, lithological interpretation often requires geological prior knowledge for guidance, which cannot be provided by remote sensing images. Thus, this study designed a dual-branch deep learning model to extract geological prior knowledge from geological information, and improve the accuracy of LUC. In the process of feature transmission of the model, a Dense Attention residual-atrous spatial pyramid pooling (DA-ASPP) module was proposed to maximize the preservation of lithological units ' features. The DA-ASPP integrates the idea of dense connection into ASPP for multiscale object feature preservation and adds residual structure into the channel attention mechanism to screen out the representative features of lithological units. The study area was located in southeastern Hubei Province, China, with seven categories of lithological units. A total of seven deep learning networks were compared. The proposed method achieved a mean intersection over union (IOU) of 44.61% with a Macro-F1 of 56.54%, which were better than those of comparison models. Moreover, the visualization results demonstrated the superiority of the proposed model in LUC.

关键词： Dense attention residual dual branches lithological unit classification (LUC) prior knowledge remote sensing.

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CUG-STCN: A seabed topography classification framework based on knowledge graph-guided vision mamba network

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INTERNATIONAL JOURNAL OF APPLIED EARTH OBSERVATION AND GEOINFORMATION 2025年 136卷

作者： Wang, Haoyi chen, Weitao Li, Xianju Liang, Qianyong Qin, xuwen Li, Jun China Univ Geosci Fac Comp Sci Wuhan 430074 Peoples R China China Univ Geosci Key Lab Geol Survey & Evaluat Minist Educ Wuhan 430074 Peoples R China China Geol Survey Guangzhou Marine Geol Survey Guangzhou 511400 Peoples R China China Geol Survey China Aero Geophys Survey & Remote Sensing Ctr Nat Beijing 100083 Peoples R China

Multibeam sounding is a high-precision remote sensing method for seabed detection. Seabed topography classification is crucial for marine science research, resource exploration and engineering. When using multibeam data for seabed topography automatic classification, the fuzzy boundaries of different topographic entities, redundancy of multimodal data, and the lack of geological knowledge guidance have led to low classification accuracy. Thus, a knowledge graph-guided vision mamba seabed topography classification network (CUG-STCN) was constructed, consisting of three modules: (1) The long sequence modeling mamba-based encoder addresses the fuzzy seabed topography boundary. It uses 2D-selective-scan to create image blocks in different scanning directions. By combining with the selective state space model to capture long-range dependencies and ensure transmission of spatial context information while maintaining linear computational complexity. (2) The crossmodal information interaction and fusion module addresses the redundancy of multimodal information. By employing a bidirectional information interaction mechanism, it captures the correlations of seabed topography between different modalities and achieving feature fusion. (3) The seabed topography knowledge graph-guided semantic perception module guides the geological knowledge. It constructs seabed topography knowledge vectors through entity query and word embedding, using the similarity between vectors to create a similarity measurement matrix. It provides geological knowledge, enhancing the modeling capability of complex seabed topography relationship. CUG-STCN achieves OA of 90.11% and mIOU of 48.50%, outperforming six mainstream networks, which at most, achieve the OA and mIOU improvements of 5.37% and 14.18%. Notably, the application of CUG-STCN in other regions demonstrates its strong generalization performance.

关键词： Multibeam Seabed topography Mamba Knowledge graph Remote sensing

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