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Reduction of Space Debris Collision Prediction Uncertainty Based on Q-Sat Precise Orbit

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Space(Science & Technology) 2023年第1期3卷 1-9页

作者： Huang pu Wen Guangwei cai Yingkai wang Zhaokui School of Aerospace Engineering Tsinghua UniversityBeijingChina

Collision probability is employed for evaluating whether there will be a dangerous encounter between 2 space *** fidelity of the collision probability mainly depends on the accuracies of orbit prediction and covariance prediction for the space *** this paper,the collision probability between the Tsinghua Gravitation and Atmosphere Science Satellite,Q-Sat,and the space debris with a North American Aerospace Defense Command ID of 49863 on 2022 January 18 was *** 2 objects approached each other dangerously close and the event was ***,the atmospheric density model is modified by a dynamic approach-based inversion to improve the accuracy of orbit prediction for the ***,predictions of position error covariance are carried *** of the next 24 hours are predicted,and the predicted orbits are compared with the actual orbits of the *** neural network was trained for predicting the position error *** the space debris,the 2-line element data are *** predictions for the space debris are also conducted and compared with the actual *** backpropagation neural network for predicting the position error covariance for the space debris is *** the covariances from the backpropagation neural network,the error ellipsoids of the 2 objects are *** error ellipsoids are later projected to the encounter plane to calculate the collision *** from the reports from other institutes,the closest distance between the Q-Sat and the space debris calculated by the current method was 2.71 *** collision probability was 1.16×10−*** was not a dangerous encounter *** onboard precise orbit determination device enabled improved orbit determination precision and orbit prediction accuracy,which is important for space safety management.

关键词： collision precise debris

Slight shading after anthesis increases photosynthetic productivity and grain yield of winter wheat (Triticum aestivum L.) due to the delaying of leaf senescence

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Journal of Integrative Agriculture 2016年第1期15卷 63-75页

作者： XU cai-long TAO Hong-bin wang pu wang Zhen-lin College of Agriculture and Biotechnology China Agricultural University National Key Laboratory of Crop Biology Agronomy College Shandong Agricultural University

The solar radiation intensity and duration are continuously decreasing in the major wheat planting area of China. As a con- sequence, leaf senescence, photosynthesis, grain filling and thus wheat yield shall be affected by light deficiency. Therefore, two winter wheat （Triticum aestivum L.） cultivars, Tainong 18 （a large-spike cultivar） and Ji＇nan 17 （a multiple-spike cultivar）, were subjected to shading during anthesis and maturity under field condition in 2010-2011 and 2011-2012. Under the slight shading treatment （$1,88% of full sunshine）, leaf senescence was delayed, net photosynthesis rate （Po） and canopy apparent photosynthesis rate （CAP） were improved, and thus thousand-kernel weight （TKW） and grain yield were higher as compared with the control. However, mid and severe shading （S2 andS3, 67 and 35% of full sunshine, respectively） led to negative effects on these traits substantially. Moreover, superoxide dismutase （SOD）, peroxidase （POD） and cat- alase （CAT） activities in flag leaf were significantly greater under slight shading than those in other treatments, while the malondialdehyde （MDA） content was less than that under other treatments. In addition, the multiple-spike cultivar is more tolerant to shading than large-spike cultivar. In conclusion, slight shading after anthesis delayed leaf senescence, enhanced photosynthesis and grain filling, and thus resulted in higher grain yield.

关键词： winter wheat shading photosynthesis leaf senescence grain yield

Reversible regulation of enzyme-like activity of molybdenum disulfide quantum dots for colorimetric pharmaceutical analysis

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Journal of Pharmaceutical Analysis 2022年第1期12卷 113-121页

作者： Juan Tan Shiyue Wu Qingqing cai Yi wang pu Zhang Engineering Research Center for Biotechnology of Active Substances Ministry of EducationChongqing Key Laboratory of Green Synthesis and ApplicationsCollege of ChemistryChongqing Normal UniversityChongqing401331China Chongqing Research Center for Pharmaceutical Engineering College of PharmacyChongqing Medical UniversityChongqing400016China

Regulating the catalytic activity of nanozymes is significant for their applications in various ***,we demonstrate a new strategy to achieve reversible regulation of the nanozyme’s activity for sensing *** strategy involves the use of zero-dimensional MoS;quantum dots(MQDs)as the building blocks of nanozymes which display very weak peroxidase(POD)-like ***,such POD-like activity of the MQDs largely enhances in the presence of Fe;while diminishes with the addition of captopril *** investigations identify the mechanism of Fe;-mediated aggregation-induced enhancement of the POD-like activity and the inhibitory effect of captopril on the enhancement,which is highly dependent on their *** on this finding,a colorimetric method for the detection of captopril is *** sensing approach exhibits the merits of simplicity,rapidness,reliability,and low cost,which has been successfully applied in quality control of captopril in pharmaceutical ***,the present sensing platform allows smartphone read-out,which has promising applications in point-of-care testing devices for clinical diagnosis and drug analysis.

关键词： Nanozyme Aggregation Peroxidase Captopril Colorimetric detection Smartphone

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运动干预与细胞焦亡在骨关节炎中的作用

中国组织工程研究 2025年第8期29卷 1667-1675页

作者：王秋月靳攀蒲锐长江大学教育与体育学院湖北省荆州市434023 长江大学医学部湖北省荆州市434023 长江大学运动人体科学实验室湖北省荆州市434023

背景:细胞焦亡参与软骨细胞外基质降解、滑膜炎症以及疼痛,在骨关节炎防治中发挥重要作用。此外,运动可通过抑制细胞焦亡调控骨关节炎的发生,已成为防治骨关节炎的研究热点。目的:总结细胞焦亡在骨关节炎中的调控作用,以及运动介导细胞... 详细信息

背景:细胞焦亡参与软骨细胞外基质降解、滑膜炎症以及疼痛,在骨关节炎防治中发挥重要作用。此外,运动可通过抑制细胞焦亡调控骨关节炎的发生,已成为防治骨关节炎的研究热点。目的:总结细胞焦亡在骨关节炎中的调控作用,以及运动介导细胞焦亡在改善骨关节炎中的机制。方法:以“pyroptosis,osteoarthritis,chondrocyte pyroptosis,synovial cell pyroptosis,exercise”和“细胞焦亡,骨关节炎,软骨细胞焦亡,滑膜细胞焦亡,运动”为关键词,检索pubMed与中国知网数据库1992-2024年间发表的相关文献,根据纳入及排除标准选择71篇文献进行综述。结果与结论:①骨关节炎是以软骨细胞外基质降解、滑膜炎症和软骨下骨重塑等为特点的慢性退行性关节疾病,易引起骨的器质性病变、疼痛并引发功能障碍。②细胞焦亡作为一种特殊的程序性死亡机制,其特征为细胞裂解死亡释放炎症因子引发强烈的炎症反应,与骨关节炎的发生发展关系密切。细胞焦亡可导致大量炎症因子释放,进而激活核因子κB转录,增加焦亡蛋白的产生,进而加剧骨关节炎的发生发展,因此细胞焦亡可作为骨关节炎防治的新方向。③运动可通过下调焦亡蛋白信号通路和抑制相关炎症因子表达等途径抑制软骨细胞和滑膜细胞的焦亡,从而在骨关节炎防治中发挥重要作用。有氧和无氧运动可通过抑制细胞焦亡的发生延缓骨关节炎的病理进程,中等强度的有氧运动通过抑制细胞焦亡信号通路改善骨关节炎的效果较好,无氧运动可通过提高肌肉质量进而对骨关节炎产生有益效应。

关键词：细胞焦亡骨关节炎运动运动调控信号通路综述

Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 58-69页

作者： Jie wang Wei wang Xuheng Chen Junfang Bao Qiuyue Hao Heng Zheng Runsheng Xu School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China Institue of Ironmaking Technology Baosteel Central Research InstituteShanghai 201999China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The utilization of iron coke provides a green pathway for low-carbon *** uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was ***,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric *** findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and *** provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron *** the heating rate in non-isothermal gasification can enhance the reactivity of iron *** metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon *** kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore ***,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.

关键词： low-carbon ironmaking iron coke gasification structural evolution kinetic model

Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： Zhao-Jun Zhang Wen-Wei wang Jing-Shui Zhen Bo-Cheng Li De-Cheng cai Yang-Yang Du Hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

Canopy morphological changes and water use efficiency in winter wheat under different irrigation treatments

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Journal of Integrative Agriculture 2020年第4期19卷 1105-1116页

作者： ZHAO Hong-xiang ZHANG Ping wang Yuan-yuan NING Tang-yuan XU cai-long wang pu College of Agronomy Shandong Agricultural UniversityTai'an 271018P.R.China College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193P.R.China Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

Water is a key limiting factor in agriculture. Water resource shortages have become a serious threat to global food security. The development of water-saving irrigation techniques based on crop requirements is an important strategy to resolve water scarcity in arid and semi-arid regions. In this study, field experiments with winter wheat were performed at Wuqiao Experiment Station, China Agricultural University in two growing seasons in 2013-2015 to help develop such techniques. Three irrigation treatments were tested: no-irrigation(i.e., no water applied after sowing), limited-irrigation(i.e., 60 mm of water applied at jointing), and sufficient-irrigation(i.e., a total of 180 mm of water applied with 60 mm at turning green, jointing and anthesis stages, respectively). Leaf area index(LAI), light transmittance(LT), leaf angle(LA), transpiration rate(Tr), specific leaf weight, water use efficiency(WUE), and grain yield of winter wheat were measured. The highest WUE of wheat in the irrigated treatments was found under limited-irrigation and grain yield was only reduced by a small amount in this treatment compared to the sufficient irrigation treatment. The LAI and LA of wheat plants was lower under limited irrigation than sufficient irrigation, but canopy LT was greater. Moreover, the specific leaf weight of winter wheat was significantly lower under sufficient than limited irrigation conditions, while the leaf Tr was significantly higher. Correlation analysis showed that the increased LAI was associated with an increase in the leaf Tr, but the specific leaf weight had the opposite relationship with transpiration. Optimum WUE occurred over a reasonable range in leaf Tr. In conclusion, reduced irrigation can optimize wheat canopies and regulate water consumption, with only small reductions in final yield, ultimately leading to higher wheat WUE and water saving in arid and semi-arid regions.

关键词： winter wheat limited-irrigation canopy characteristics transpiration rate water use efficiency

Interplay between creeping fat and gut microbiota: A brand-new perspective on fecal microbiota transplantation in Crohn's disease

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World Journal of Gastroenterology 2025年第2期31卷 138-143页

作者： Ying wang Jie Liu Department of Life Sciences and Medicine South District of Endoscopic CenterThe First Affiliated Hospital of University of Science and Technology of ChinaUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Department of Gastroenterology The First Affiliated Hospital of University of Science and Technology of ChinaHefei 230001Anhui ProvinceChina

Inflammatory bowel disease,particularly Crohn's disease(CD),has been linked to modifications in mesenteric adipose tissue(MAT)and the phenomenon known as"creeping fat"(CrF).The presence of CrF is believed to serve as a predictor for early clinical recurrence following surgical intervention in patients with ***,the incorporation of the mesentery during ileocolic resection for CD has been correlated with a decrease in surgical recurrence,indicating the significant role of MAT in the pathogenesis of *** numerous studies have indicated that dysbiosis of the gut microbiota is a critical factor in the development of CD,the functional implications of translocated microbiota within the MAT of CD patients remain *** manuscript commentary discusses a recent basic research conducted by Wu et *** their study,intestinal bacteria from individuals were transplanted into CD model mice,revealing that fecal microbiota trans-plantation(FMT)from healthy donors alleviated CD symptoms,whereas FMT from CD patients exacerbated these ***,FMT was found to affect intestinal permeability,barrier function,and the levels of proinflammatory factors and ***,these findings suggest that targeting MAT and CrF may hold therapeutic potential for patients with ***,the study did not evaluate the composition of the intestinal microbiota of the donors or the subsequent alterations in the gut ***,the gut microbiota plays a crucial role in the histopathology of CD,and thus,targeting MAT and CrF may represent a promising avenue for treatment in this patient population.

关键词： Crohn's disease Mesenteric adipose tissue Creeping fat Fecal microbiota transplantation Gut microbiota

EZH2-dependent myelination following sciatic nerve injury

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Neural Regeneration Research 2025年第8期20卷 2382-2394页

作者： Hui Zhu Li Mu Xi Xu Tianyi Huang Ying wang Siyuan Xu Yiting wang Wencong wang Zhiping wang Hongkui wang Chengbin Xue Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityKey Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo-innovation Center of NeuroregenerationNMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongJiangsu ProvinceChina Medical School of Nantong University NantongJiangsu ProvinceChina Department of Neurology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Rehabilitation Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Critical Care Medicine Nantong Fourth People’s HospitalNantongJiangsu ProvinceChina

Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve ***,the gene regulatory network of regenerated myelin differs from that of native *** of enhancer of zeste homolog 2(EZH2)hinders the differentiation,maturation,and myelination of Schwann cells in *** further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury,conditional knockout mice lacking Ezh2 in Schwann cells(Ezh2^(fl/fl);Dhh-Cre and Ezh2^(fl/fl);Mpz-Cre)were *** results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain *** highlights the crucial role of Ezh2 in initiating Schwann cell ***,we observed that 21 days after inducing a sciatic nerve crush injury in these mice,most axons had remyelinated at the injury site in the control nerve,while Ezh2^(fl/fl);Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type *** suggests that the absence of Ezh2 in Schwann cells impairs myelin formation and *** conclusion,EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve *** EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.

关键词： demyelination EZH2 myelination peripheral nerve injury PRC2 remyelination Schwann cells sciatic nerve crush sciatic nerve transection