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Object detection in crowded scenes via joint prediction

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Defence Technology（防务技术） 2023年第3期21卷 103-115页

作者： Hong-hui Xu Xin-qing Wang Dong Wang Bao-guo Duan Ting Rui Department of Mechanical Engineering College of Field EngineeringArmy Engineering University of PLANanjing210007China

Detecting highly-overlapped objects in crowded scenes remains a challenging problem,especially for one-stage *** this paper,we extricate YOLOv4 from the dilemma in a crowd by fine-tuning its detection scheme,named ***,we give YOLOv4 the power to detect multiple objects in one *** to our method is the carefully designed joint prediction scheme,which is executed through an assignment of bounding boxes and a joint *** with the derived joint-object augmentation(DJA),refined regression loss(RL)and Score-NMS(SN),YOLO-CS achieves competitive detection performance on CrowdHuman and CityPersons benchmarks compared with state-of-the-art detectors at the cost of little ***,on the widely used general benchmark COCO,YOLOCS still has a good performance,indicating its robustness to various scenes.

关键词： tuning prediction scene

Investigation of the promotion effect of Mo doped CuO catalysts for the low-temperature performance of NH_(3)-SCR reaction

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Chinese Chemical Letters 2022年第12期33卷 5223-5227页

作者： hui Wang Ting Zhu Yujie Qiao Shicheng Dong Zhenping Qu Key Laboratory of Industrial Ecology and Environmental Engineering(MOE) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

A novel Mo-doped CuO catalyst is developed and used for low-temperature NH_(3)-SCR *** with the undoped CuO sample,the Mo doped CuO catalyst shows an increased SCR performance with above 80%NO_(x) conversion at 175℃.The XRD and Raman results have confirmed the incorporation of Mo metal ions into CuO lattice to form Mo-O-Cu species which may be related to the enhanced SCR *** XPS and UV-vis results reveal the creation of electron interaction between Cu and Mo in this Mo-O-Cu system which provides an increased amount of Lewis and Brønsted acid sites,thereby promoting the adsorption capacity of NH_(3) and NO_(x) as verified by NH_(3)-TPD and NO_(x)-TPD ***,it also promotes the formation of oxygen vacancies,leading to the increasing of chemisorbed oxygen species,which improves the NO oxidation to NO_(2) ***,in situ DRIFTS technology was also used to study the reaction mechanism of this Mo doped CuO *** formed NO_(2) could react with NHx(x=3,2)species to enhance the low-temperature NH_(3)-SCR activity via the"fast-SCR"reaction *** nitrate and nitrite ad-species may react with NH_(3) and NH4^(+)ad-species through the L-H pathway.

关键词： Mo doped CuO NH_(3)-SCR NO_(x) Solid solution Low-temperature Reaction mechanism

Polyhydroxylated eudesmane sesquiterpenoids and sesquiterpenoid glucoside from the flower buds of Tussilago farfara

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Chinese Journal of Natural Medicines 2022年第4期20卷 301-308页

作者： LI Yu-Peng YANG Kang MENG hui SHEN Tao ZHANG Hua School of Biological Science and Technology University of JinanJinan 250022China Key Laboratory of Chemical Biology(MOE) School of Pharmaceutical SciencesShandong UniversityJinan 250012China

Chemical fractionation of the n-BuOH partition,which was generated from the EtOH extract of the flower buds of Tussilago farfara,afforded a series of polar constituents including four new sesquiterpenoids(1-4),one new sesquiterpenoid glucoside(5)and one known analogue(6)of the eudesmane type,as well as five known quinic acid derivatives(7-11).Structures of the new compounds were unambiguously characterized by detailed spectroscopic analyses,with their absolute configurations being established by A-ray crystallography,electronic circular dichroism(ECD)calculation and induced ECD *** inhibitory effect of all the isolates against LPS-induced NO production in murine RAW264.7 macrophages was evaluated,with isochlorogenic acid A(7)showing significant inhibitory activity.

关键词： Tussilago farfara Eudesmane sesquiterpenoid Anti-inflammation NO production inhibition Quinic acid derivative

Terrain-influenced wind flow of the Qitai radio telescope site

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Journal of Mountain Science 2023年第11期20卷 3173-3185页

作者： HE Fei-long XU Qian WANG Na XUE Fei WANG hui Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

The wind environment of a site is one of the important factors affecting the observation performance of large aperture and high-performance radio *** the relationship between the effects of different terrains on wind flow is important to optimize the wind environment of the *** terrain of the Qitai radio telescope(QTT)site located in east Tianshan Mountains at an elevation of about 1800 m was used to study the wind flow in the adjacent zone of antenna based on numerical *** area from 600m south to 600m north of the antenna is defined as the antenna adjacent zone,and three groups of boundaries with different terrains are set up upstream and downstream,*** the zone where the antenna is located is a slope terrain,in order to verify the influence of terrain on the wind flow and to clarify the relationship between the influence of boundary terrain on the wind flow,a control group of horizontal terrain is *** simulation results show that the wind flow is mainly influenced by the *** highest elevation of the upstream and downstream boundary terrains affects the basic wind *** upstream boundary terrain has a greater impact on wind flow than the downstream boundary *** addition,the wind speed profile index obtained by numerical simulation is smaller than the actual index for the wind from ***,the wind speed at the upper level(about 100 m)obtained by inversion based on the measured wind speed at the bottom(about 10 m)is also smaller than the actual wind speed.

关键词： Radio telescope site Terrain Wind flow characteristic Numerical simulation

Techniques for increasing the yield of stem cell-derived exosomes:what factors may be involved?

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Science China(Life Sciences) 2022年第7期65卷 1325-1341页

作者： Zi-Yuan Feng Qing-Yi Zhang Jie Tan hui-Qi Xie Laboratory of Stem Cell and Tissue Engineering Orthopedic Research InstituteMed-X Center for MaterialsState Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China

Exosomes are nano-scale extracellular vesicles secreted by cells and constitute an important part in the cell-cell *** main contents of the exosomes include proteins,micro RNAs,and *** mechanism and safety of stem cell-derived exosomes have rendered them a promising therapeutic strategy for regenerative ***,limited yield has restrained full explication of their functions and clinical *** address this,various attempts have been made to explore the up-and down-stream manipulations in a bid to increase the production of *** review has recapitulated factors which may influence the yield of stem cell-derived exosomes,including selection and culture of stem cells,isolation and preservation of the exosomes,and development of artificial exosomes.

关键词： exosome stem cell yield therapy

Demi-linear analysis Ⅲ——demi-distributions with compact support

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Applied Mathematics(A Journal of Chinese Universities) 2022年第1期37卷 1-20页

作者： LI Rong-lu ZHONG Shu-hui KIM Dohan WU Jun-de Department of Mathematics Harbin Institute of TechnologyHarbin 150001China School of Mathematics Tianjin UniversityTianjin 300350China Department of Mathematics Seoul National UniversitySeoul 151-742Korea School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China

A series of detailed quantitative results is established for the family of demidistributions which is a large extension of the family of usual distributions.

关键词： demi-linear functionals demi-distributions

Simulation of internal nitrogen release from bottom sediments in an urban lake using a nitrogen flux model

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Water Science and Engineering 2023年第3期16卷 252-260页

作者： Ran Gong hui-ya Wang Zhi-xin Hu Yi-ping Li School of Environmental Engineering Nanjing Institute of TechnologyNanjing 211167China College of Environment Hohai UniversityNanjing 210098China

Nutrient release from sediment is considered a significant source for overlying water. Given that nutrient release mechanisms in sediment are complex and difficult to simulate, traditional approaches commonly use assigned parameter values to simulate these processes. In this study, a nitrogen flux model was developed and coupled with the water quality model of an urban lake. After parameter sensitivity analyses and model calibration and validation, this model was used to simulate nitrogen exchange at the sediment–water interface in eight scenarios. The results showed that sediment acted as a buffer in the sediment–water system. It could store or release nitrogen at any time, regulate the distribution of nitrogen between sediment and the water column, and provide algae with nitrogen. The most effective way to reduce nitrogen levels in urban lakes within a short time is to reduce external nitrogen loadings. However, sediment release might continue to contribute to the water column until a new balance is achieved. Therefore, effective measures for reducing sediment nitrogen should be developed as supplementary measures. Furthermore, model parameter sensitivity should be individually examined for different research subjects.

关键词： Diagenesis Nitrogen flux model EFDC Urban lake Modeling Latin hypercube sampling

A Comparative Study of the Power-law Relationship between the Pulse width and Energy of Precursor and Main Burst

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Research in Astronomy and Astrophysics 2024年第3期24卷 144-168页

作者： hui-Ying Deng Zhao-Yang Peng Jia-Ming Chen Dan Zhu College of Physics and Electronic Information Yunnan Normal UniversityKunming 650500China

In gamma-ray burst prompt emission,there is still no consistent conclusion if the precursor and main burst share the same *** this paper,we try to study this issue based on the relationship between pulse width and energy of the precursor and main *** systematically search the light curve data observed by Swift/BAT and Fermi/GBM,and find 13 long bursts with well-structured precursors and main *** fitting the precursor light curve of each different energy channel with the Norris function,we find that there is not only a power-law relationship between precursor width and energy,but also a power-law relationship between the ratio of the rising width to the decaying width and *** comparing the relationship between the precursors and the main burst pulses,we find that the distribution of the precursors and the relationship between the power-law indices are roughly the same as those of the main *** addition,it is found that the precursor width distribution as well as the upper limit of the pulse width ratio does not exceed 1 and both are asymmetric,which are also consistent with the main *** indicate that the precursor and the main burst are indistinguishable,and the precursor and the main burst may have the same physical origin.

关键词： methods data analysis-(stars) gamma-ray burst general-shock waves

Single-nucleus RNA and ATAC sequencing reveals the impact of chromatin accessibility on gene expression in Arabidopsis roots at the singlecell level

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Molecular Plant 2021年第3期14卷 372-383页

作者： Andrew Farmer Sandra Thibivilliers Kook hui Ryu John Schiefelbein Marc Libault National Center for Genome Resources Santa FeNM 87505USA Department of Agronomy and Horticulture Center for Plant Science InnovationUniversity of Nebraska-LincolnBeadle CenterLincolnNE 68503USA Department of Molecular Cellularand Developmental BiologyUniversity of MichiganAnn ArborMI 48109USA

Similar to other complex organisms,plants consist of diverse and specialized cell *** gain of unique biological functions of these different cell types is the consequence of the establishment of cell-typespecific transcriptional *** a necessary step in gaining a deeper understanding of the regulatory mechanisms controlling plant gene expression,we report the use of single-nucleus RNA sequencing(sNucRNA-seq)and single-nucleus assay for transposase accessible chromatin sequencing(sNucATACseq)technologies on Arabidopsis *** comparison of our single-nucleus transcriptomes to the published protoplast transcriptomes validated the use of nuclei as biological entities to establish plant cell-type-specific ***,our sNucRNA-seq results uncovered the transcriptomes of additional cell subtypes not identified by single-cell *** to our transcriptomic approach,the sNucATAC-seq approach led to the distribution of the Arabidopsis nuclei into distinct clusters,suggesting the differential accessibility of chromatin between groups of cells according to their *** reveal the impact of chromatin accessibility on gene expression,we integrated sNucRNA-seq and sNucATAC-seq data and demonstrated that cell-type-specific marker genes display cell-type-specific patterns of chromatin *** data suggest that the differential chromatin accessibility is a critical mechanism to regulate gene activity at the cell-type level.

关键词： single-cell RNA-seq single-nucleus ATAC-seq Arabidopsis root