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Kinematics of the Open Cluster System in the Galaxy

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Chinese Journal of Astronomy and Astrophysics 2006年第3期6卷 287-296页

作者： jun-Liang zhao Li chen Zhong-Liang Zu Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030

Absolute proper motions and radial velocities of 202 open clusters in the solar neighborhood, which can be used as tracers of the Galactic disk, are used to investigate the kinematics of the Galaxy in the solar vicinity, including the mean heliocentric velocity components （u1, u2, u3） of the open cluster system, the characteristic velocity dispersions （σ1,σ2,σ3）, Oort constants （A, B） and the large-scale radial motion parameters （C, D） of the Galaxy. The results derived from the observational data of proper motions and radial velocities of a subgroup of 117 thin disk young open clusters by means of a maximum likelihood algorithm are：（u1,u2,u3） = （-16.1 ± 1.0,-7.9 ±1.4,-10.4±1.5） km·s^-1, （σ1,σ2,σ3） = （17.0±0.7, 12.2±0.9, 8.0±1.3） km·S^-1, （A, B） = （14.8±1.0, - 13.0±2.7） km·s^-1 kpc^-1, and （C, D） = （1.5 ± 0.7, -1.2 ±1.5） km·s^-1 kpc^-1. A discussion on the results and comparisons with what was obtained by other authors is given.

关键词： Galaxy: kinematics and dynamics - open clusters and associations: general

Mechanism of Slag Composition Change During Electroslag Remelting Process

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Journal of Iron and Steel Research International 2011年第10期18卷 24-28,53页

作者： zhao jun-xue chen Yan-mei LI Xiao-ming CUI Ya-ru LU Xiao-tao School of Metallurgical Engineering Xi＇an University of Architecture and Technology Xi＇an 710055 Shannxi China

The mass loss rate of CaF2-CaO-Al2O3-SiO2-MgO slag system originated from ANF-6 was studied with CaF2, CaO, Al2O3, SiO2 or MgO content as variables. The method of quadratic regression orthogonal design was used for the design and analysis of the experiment. The experimental results indicated that mass loss rate of slag can be increased by 6% with CaF2 changing from 50%to 65%. Mass loss increases with SiO2 , Al2O3 and MgO adding and decreases with CaO content increasing. Because of the reaction between oxide and fluoride in the slag pool, apparent mass loss of CaF2-Al2O3 CaO-SiO2 MgO slag system appears at melting point. This will cause obvious composition change of electroslag. In addition, the segregation occurs in the slag skin forming process. This is another reason causing the composition change of electroslag.

关键词： electroslag DSC-TG analysis quadratic regression orthogonal design composition change

A bibliometric analysis and visualization of osteochondral lesions of talus (2004-2021)

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Medical Data Mining 2024年第3期7卷 17-25页

作者： Xiao-Jie Sun Shu-Long Wang Zi-Dong Wang zhao-jun chen The Third Affiliated Hospital of Beijing University of Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China Department of Hand and Foot Surgery The Third Affiliated Hospital of Beijing University of Chinese MedicineBeijing 100029China School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese MedicineBeijing 100029China

Background:Osteochondral lesions of the talus(OLTs)are a significant challenge for foot and ankle specialists,which could cause pain and decrease patient *** can use the findings of this study to shape future directions for research by exploring global trends and hotspots in ***:Web of Science Core Collection was used to retrieve literature related to OLT between 2004 and *** report covers the current state of OLTs,such as publications,journals,trends,hotspots,and the performances of relevant countries,institutions and *** co-citation analysis,the coauthorship analysis,the cooccurrence analysis,and the bibliographic coupling analysis were conducted with the Bibliometrix R package,VOSviewer v1.***.10.0,and CiteSpace ***:During an 18-year review,717 articles and 76 review articles on OLT published from 2004 to 2021 were *** USA has made the largest contribution to the OLT-related literature,and a significant contribution has been made by Kennedy JG(48/6.05%)and van Dijk CN(30/3.78%).In terms of total link strength,Foot&Ankle International was the leading *** showed that the global research hotspots of OLTs focused on the pathogenesis,diagnosis,clinical research,and surgical treatment of *** would be significant to pay close attention to future research on osteochondral autograft transplantation and management,surgery,multidisciplinary integration and mechanisms of OLT,and its related ***:The study provides information about the current status and hotspots of research in the domain of OLT over the past 18 years that will assist researchers in identifying potential perspectives on hot topics and research frontiers.

关键词： bibliometric analysis hotspots osteochondral lesions of the talus trends visualised analysis

Effects of corneal stromal cell-and bone marrow-derived endothelial progenitor cell-conditioned media on the proliferation of corneal endothelial cells

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International Journal of Ophthalmology(English edition) 2016年第3期9卷 332-339页

作者： Meng-Yu Zhu Qin-Ke Yao jun-zhao chen Chun-Yi Shao chen-Xi Yan Ni Ni Xian-Qun Fan Ping Gu Yao Fu Department of Ophthalmology Shanghai Ninth People's HospitalShanghai Jiao Tong University School of Medicine

AIM： To explore the effects of conditioned media on the proliferation of corneal endothelial cells （CECa） and to compare the efficiency of different conditioned media （CM）. METHODS： Rat CECs, corneal stromal cells （CSCs）, bone marrow -derived endothelial progenitor cells （BEPCs）, and bone marrow-derived mesenchymal stem cells （BMSCs） were isolated and cultured in vitra CM was collected from CSCs, BEPCs, and BMSCSo CECs were cultivated in different culture media. Cell morphology was recorded, and gene and protein expression were analyzed.~ RESULTS： After grown in CM for 5d, CECs in each experimental group remained polygonal, in a cobblestone- like monolayer arrangement. Immunocytofluorescence revealed positive expression of Na＋/K＋-ATP, aquaporin 1 （AQP1）, and zonula occludens 1 （ZO-1）. Based on quantitative polymerase chain reaction （qPCR） analysis, Na ＋/K ＋-ATP expression in CSC-CM was notably upregulated by 1.3-fold （＋0.036）（P〈0.05, n=3）. The expression levels of ZO-1, neuron specific enolase （NSE）, Vimentin, paired homebox 6 （PAX6）, and procollagen type VII （COL8A1） were notably upregulated in each experimental group. Each CM had a positive effect on CEC proliferation, and CSC-CM had the strongest effect on proliferation.~ CONCLUSION： CSC-CM, BEPC-CM, and BMSC-CM not only stimulated the proliferation of CECs, but also maintained the characteristic differentiated phenotypes necessary for endothelial functions. CSC-CM had the most notable effect on CEC proliferation. KEYWORDS： conditioned medium; corneal endothelial cell; corneal stromal cell; bone marrow-derived endothelial progenitor cell; proliferation

关键词： conditioned medium corneal endothelialcell corneal stromal cell bone marrow-derived endothelialprogenitor cell proliferation

A New Location Precision Model for Multi-Static Over-the-Horizon Radar System

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Wuhan University Journal of Natural Sciences 2010年第2期15卷 143-147页

作者： SONG jun, zhao Zhengyu, ZHOU chen School of Electronic Information, Wuhan University, Wuhan 430072, Hubei, China School of Electronic Information Wuhan University Wuhan China

In this paper, a multi-static system working in an active way is made up of ionospheric oblique backscatter sounding system （IOBSS） and two separate receiving stations, which adopts discontinuous wave mechanism. We have advanced a new model that contains skywave condition to locate over-the-horizon targets. We use a single quasi-parabolic （QP） ionosphere model and an analytic ray-tracing program to obtain the coordinate registration （CR） index, which changes skywave group range to ground range. Also, IOBSS and other two receiving stations use this distance information to locate the target which is far away from the system. The analytic expression for the geometric dilution of precision （GDOP） under different station deployments are obtained, which shows GDOP is influenced by the system measurement precision, the stations＇ coordinates, and CR index. By computer simulation, we find that GDOP of isosceles right triangle deployment is smaller than that of line deployment and location precision will be improved with increasing base line length. The results indicate that this model is practicable with an acceptable range of error （less than 500 m under certain conditions in this paper）.

关键词： over-the-horizon radar (OTHR) multi-static coor-dinate registration target location

Exit options sustain altruistic punishment and decrease the second-order free-riders, but it is not a panacea

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Science China(Information Sciences) 2025年第1期68卷 278-291页

作者： chen SHEN zhao SONG Lei SHI jun TANIMOTO Zhen WANG Faculty of Engineering Sciences Kyushu University School of Statistics and Mathematics Yunnan University of Finance and Economics School of Computing Engineering and Digital Technologies Teesside University School of Artificial Intelligence OPtics and Electro Nics (iOPEN) Northwestern Polytechnical University

Why do humans punish free riders at their own expense? This behavior represents an evolutionary puzzle in human societies. This study explores the role of exit strategies in fostering altruistic punishment within evolutionary game theory. We extend the traditional prisoner's dilemma model by incorporating exiters, players who opt out for a small payoff while nullifying their opponent's payoff, and altruistic punishers who cooperate and punish non-cooperators. Our findings indicate that in well-mixed populations, exiters destabilize defection but do not promote altruistic punishment. In social networks, however,exiters enable altruistic punishment via cyclic dominance among altruistic punishers, defectors, and exiters. Notably, this cyclic dominance is sensitive to exit payoffs; adjustments can lead to cyclic dominance of non-punishing cooperators, defectors, and exiters, or to a bi-stable state between these two types of cyclic dominance. These results highlight the nuanced impact of exiters on altruistic punishment, emphasizing the need for careful incentivization of exit behavior. While exiters can support altruistic punishment in networked populations, their effectiveness is not a panacea and is highly sensitive to exit payoffs, indicating limits to the voluntary participation mechanism.

关键词： evolutionary game theory altruistic punishment coexistence cyclic dominance bi-stable

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu chen Xue-jun Li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

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基于混沌蚁群算法的大时滞对象神经网络控制

上海交通大学学报 2008年第7期42卷 1198-1202页

作者：赵俊陈建军西安电子科技大学机电工程学院西安710071

为了有效控制未知大时滞对象,以最小二乘支持向量机为辨识器,通过改进模糊PID控制,构造了一种智能型神经网络作为控制器.在此控制方案下,对蚁群算法引入混沌搜索机制进行改进,将其应用于控制器参数的离线优选.仿真结果表明:该方案及其... 详细信息

为了有效控制未知大时滞对象,以最小二乘支持向量机为辨识器,通过改进模糊PID控制,构造了一种智能型神经网络作为控制器.在此控制方案下,对蚁群算法引入混沌搜索机制进行改进,将其应用于控制器参数的离线优选.仿真结果表明:该方案及其优化策略能有效改善系统的性能,稳态无静差,动态性能好,且具有一定的鲁棒性.

关键词：未知大时滞对象模糊PID控制最小二乘支持向量机神经网络混沌蚁群优化

Emerging progress: photochemical transformation of nitroso compounds

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Science China Chemistry 2025年第1期68卷 118-133页

作者： Ze-Le chen Qiang-Qiang Li Armido Studer jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry & Chemical Engineering Anhui University Organisch-Chemisches Institut Universitat Münster

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles, nucleophiles, diradicals, and radical acceptors in diverse transformations. In recent years, notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions. Various nitroso compounds like nitrosoarenes, acyloxy nitroso compounds, N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access. In this review, we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds, with particular emphasis on their role as bifunctional reagents and acceptors of radicals, carbenes and nitrenes.

关键词： nitroso compounds photochemistry radical reaction carbene transformation nitrosoarenes