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Modeling and analysis of colored petri net based on the semi-tensor product of matrices

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Science China(Information Sciences) 2018年第1期61卷 70-85页

作者： Jiantao ZHAO Zengqiang chen Zhongxin LIU College of Computer and Control Engineering Nankai University Key Laboratory of Intelligent Robotics of Tianjin Nankai University

This paper applies the model petri net method based on the semi-tensor product of matrices to colored petri net. Firstly, we establish the marking evolution equation for colored petri net by using the semitensor product of matrices. Then we define the concept of controllability and the control-marking adjacency matrix for colored petri net. Based on the marking evolution equation and control-marking adjacency matrix, we give the necessary and sufficient condition of reachability and controllability for colored petri net. The algorithm to verify the reachability of colored petri net is given, and we analyze the computational complexity of the algorithm. Finally, an example is given to illustrate the effectiveness of the proposed theory. The significance of the paper lies in the application of the model petri net method based on the semitensor product of matrices to colored petri net. This is a convenient way of verifying whether one marking is reachable from another one as well as finding all firing sequences between any two reachable ***, the method lays the foundations for the analysis of other properties of colored petri net.

关键词： colored petri net reachability controllability marking evolution equation semi-tensor product of matrices

Silicon cuboid nanoantenna with simultaneous large Purcell factor for electric dipole,magnetic dipole and electric quadrupole emission

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Opto-Electronic Advances 2022年第2期5卷 13-21页

作者： Qiurong Deng Jianfeng chen Li Long Baoqin chen Huakang Yu Zhiyuan Li School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China

The Purcell effect is commonly used to increase the spontaneous emission rate by modifying the local environment of a light ***,we propose a silicon dielectric cuboid nanoantenna for simultaneously enhancing electric dipole(ED),magnetic dipole(MD)and electric quadrupole(EQ)*** study the scattering cross section,polarization charge distribution,and electromagnetic field distribution for electromagnetic plane wave illuminating the silicon dielectric cuboid nanoantenna,from which we have identified simultaneous existence of ED,MD and EQ resonance modes in this *** have calculated the Purcell factor of ED,MD and EQ emitters with different moment orientations as a function of radiation wavelength by placing these point radiation source within the nanoantenna,*** find that the resonances wavelengths of the Purcell factor spectrum are matching with the resonance modes in the ***,the maximum Purcell factor of these ED,MD and EQ emitters is 18,150 and 118 respectively,occur-ring at the resonance wavelength of 475,750,and 562 nm,respectively,all within the visible *** polarization charge distribution features allow us to clarify the excitation and radiation of these resonance modes as the physical ori-gin of large Purcell factor simultaneously occurring in this silicon cuboid *** theoretical results might help to deeply explore and design the dielectric nanoantenna as an ideal candidate to enhance ED,MD and EQ emission simultaneously with very small loss in the visible range,which is superior than the more popular scheme of plasmonic nanoantenna.

关键词： dielectric nanostructure spontaneous emission resonance Purcell effect

TWO-SCALE FEM FOR ELLIPTIC MIXED BOUNDARY VALUE PROBLEMS WITH SMALL PERIODIC COEFFICIENTS

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Journal of Computational Mathematics 2001年第5期19卷 549-560页

作者： Jin-ru chen Jun-zhi Cui School of Mathematics and Computer Sciences Nanjing Normal UniversityNanjing 210097China ICMSEC Academy of Mathematics and Systems SciencesChinese Academy of SciencesBeijing 100080China

Presents a study which proposed a dual approximate expression of the exact solution for mixed boundary value problems of second order elliptic partial differential equation with small periodic coefficients. Dual appro... 详细信息

关键词： two-scale FEM mixed boundary value small periodic coefficients

Spherical Cu2O Assembled by Small Nanoparticles and Its High Efficiency in Photodegradations of Methylene Blue Under Different Light Sources

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Chemical Research in Chinese Universities 2020年第6期36卷 1108-1115页

作者： chen Peiwen ZHU Lianjie CHANG Zhuangzhuang GAO Hongjia chen Deyou QIU Mo School of Chemistry&Chemical Engineering Tianjin Key Laboratory of Organic Solar Cells and Photochemical ConversionTianjin University of TechnologyTianjin 300384P.R.China Agro-Environmental Protection Institute Chinese Academy of Agricultural SciencesTianjin 300191P.R.China

Well-dispersed mesoporous spherical Cu2O assembled by small nanoparticles was synthesized by a green and rapid solution route at room temperature under assistance of ultrasonic,using eco-friendly ascorbic acid(AA)as the main reducing agent and glucose as a weak reducing agent and soft *** CuO spheres were characterized by XRD,SEM,HRTEM,XPS and N2 adsorption-desorption *** optical property was studied by UV-Vis diffuse reflectance absorption spectrum and the photocatalytic activities were evaluted by photodegradations of me thylene blue(MB)under different light *** results show that each spherical Cu2O(ca.200 nm in diameter)was accumulated by numerous small nanoparticles of 8-10 nm and mesopores exist between the nanoparticles,which result in a high BET surface *** spherical Cu2O exhibits good light-harvesting ability in both UV and visiblelight region and excellent photodegradation activities to high concentrations of MB solutions under both UV-visible light and visible light.

关键词： Spherical Cu2O Photodegradation Methylene blue Visible light

Understanding the mechanistic regulation of ferroptosis in cancer:the gene matters

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Journal of Genetics and Genomics 2022年第10期49卷 913-926页

作者： Min Gao Kexin Fan Yuhan chen Guangjian Zhang Jing chen Yilei Zhang The Institute of Molecular and Translational Medicine Department of Biochemistry and Molecular BiologySchool of Basic Medical SciencesXi'an Jiaotong University Health Science CenterXi'anShaanxi 710061China Department of Thoracic Surgery The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'anShaanxi 710061China Department of Obstetrics Xi'an New Chang'an Maternity HospitalXi'anShaanxi 710001China Shaanxi Stem Cell Engineering Application Research Center Shaanxi Jiuzhou Biomedical Science and Technology GroupXi'anShaanxi 710065China

Ferroptosis has emerged as a crucial regulated cell death involved in a variety of physiological processes or pathological diseases,such as tumor *** initially being found from anticancer drug screening and considered not essential as apoptosis for growth and development,numerous studies have demonstrated that ferroptosis is tightly regulated by key genetic pathways and/or genes,including several tumor suppressors and *** this review,we introduce the basic concepts of ferroptosis,characterized by the features of non-apoptotic,iron-dependent,and overwhelmed accumulation of lipid peroxides,and the underlying regulated circuits are considered to be pro-ferroptotic ***,we discuss several established lipid peroxidation defending systems within cells,including SLC7A11/GPX4,FSP1/CoQ,GCH1/BH4,and mitochondria DHODH/CoQ,all of which serve as anti-ferroptotic pathways to prevent ***,we provide a comprehensive summary of the genetic regulation of ferroptosis via targeting the above-mentioned pro-ferroptotic or anti-ferroptotic *** regulation of proand anti-ferroptotic pathways gives rise to more specific responses to the tumor cells in a contextdependent manner,highlighting the unceasing study and deeper understanding of mechanistic regulation of ferroptosis for the purpose of applying ferroptosis induction in cancer therapy.

关键词： Ferroptosis Ferroptotic pathways Genetic regulation Tumor suppression Cancer therapy

Dielectric and ferroelectric characteristics of Ba(Ti_(0.25)Zr_(0.25)Hf_(0.25)Sn_(0.25))O_(3)high-entropy ceramics

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Journal of Materiomics 2023年第4期9卷 634-641页

作者： Rui Hu Mi Bu Hang chen Xiao Li Zhu Xiang Ming chen School of Materials Science and Engineering Zhejiang UniversityHangzhou310027China

Ba(Ti_(0.25)Zr_(0.25)Hf_(0.25)Sn_(0.25))O_(3)high-entropy ceramics were prepared by a standard solid state reaction process,and the dielectric and ferroelectric characteristics were investigated together with the *** X-ray diffraction(XRD)and energy dispersive spectroscopy(EDS)analysis demonstrated a single-phase perovskite structure in the present ceramics.A broad dielectric peak with strong frequency dispersion feature was determined,which indicated the typical relaxor nature originating from the nanoscale ferroelectric domain *** resulted from the structural distortion and chemical disorder due to high-entropy,where the long-range order of ferroelectric domains was *** homogeneous microstructure led to the reduced leakage current density and significantly improved dielectric strength,which was desired for the practical *** with the similar systems of Ba(Ti_(1-x)Zr_(x))O_(3)&Ba(Ti_(1-x)Sn_(x))O_(3),the present high-entropy ceramics indicated better relaxor ferroelectric characteristics.

关键词： High-entropy ceramic Microstructure Perovskite Relaxor ferroelectric

A New Brown Frog of the Genus Rana(Anura,Ranidae)from North China,with a Taxonomic Revision of the *** Species Group

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Asian Herpetological Research 2022年第3期13卷 145-158页

作者： Huijun SHEN Mengyu XU Xinyue YANG Zhuo chen Nengwen XIAO Xiaohong chen College of Life Sciences Henan Normal UniversityXinxiang 453007HenanChina The Observation and Research Field Station of Taihang Mountain Forest Ecosystems of Henan Province Xinxiang 453007HenanChina State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

The Rana chensinensis species group is widely distributed throughout North ***,its taxonomy and composition remain *** recent field investigations of the Taihang Mountains,a series of Rana specimens were collected,which were once identified as ***,these samples showed significant differences from *** of the type locality(Shaanxi Province in the Qinling Mountains)in both morphology and *** this paper,based on analyses of seventeen geographic populations from the Taihang and Qinling Mountains,we describe a new species(namely *** ***.)in the *** species group.A phylogenetic analysis of the *** species group based on mitochondrial genes—COI,16S rRNA and Cytb—revealed the monophyly of the cryptic species,which formed the sister taxon to *** comparisons indicated that the cryptic species can be distinguished from its congeners by a combination of ***,the distribution patterns of the Rana species in North China were *** populations of the southwestern Taihang Mountains,Xiaoqinling Mountains,and Funiu Mountains in Henan Province remain ***,whereas the populations recorded as *** in Beijing City,Hebei Province,and the southeastern Taihang Mountains of Henan Province should be revised as *** ***.

关键词： morphology phylogeny Rana taihangensis sp.nov Rana chensinensis species group taxonomic revision

Difference between CKD-EPI and MDRD equations in calculating glomerular filtration rate in patients with cirrhosis

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World Journal of Gastroenterology 2011年第40期17卷 4532-4538页

作者： Yu-Wei chen Han-Hsiang chen Tsang-En Wang Ching-Wei Chang chen-Wang Chang Chih-Jen Wu Division of Nephrology Department of Internal Medicine Mackay Memorial Hospital Taipei 10449 Taiwan Mackay Medicine Nursing and Management College Taipei 10449 Taiwan National Taipei College of Nursing Taipei 10449 Taiwan Division of Gastroenterology Department of Internal Medicine Mackay Memorial Hospital Taipei 10449 Taiwan Graduate Institute of Medical Science Taipei Medical University Taipei 11031 Taiwan

AIM:To evaluate the difference between the performance of the (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) equations in cirrhotic patients. METHODS: From Jan 2004 to Oct 2008, 4127 cirrhotic patients were reviewed. Patients with incomplete data with respect to renal function were excluded; thus, a total of 3791 patients were included in the study. The glomerular filtration rate (GFR) was estimated by the 4-variable MDRD (MDRD-4), 6-variable MDRD (MDRD-6), and CKD-EPI ***:When serum creatinine was 0.7-6.8 mg/dL and 0.6-5.3 mg/dL in men and women, respectively, a significantly lower GFR was estimated by the MDRD-6 than by the CKD-EPI. Similar GFRs were calculated by both equations when creatinine was > 6.9 mg/dL and > 5.4 mg/dL in men and women, respectively. In predicting in-hospital mortality, estimated GFR obtained by the MDRD-6 showed better accuracy [81.72%; 95% confidence interval (CI), 0.94-0.95] than that obtained by the MDRD-4 (80.22%; 95%CI, 0.96-0.97), CKD-EPI (79.93%; 95%CI, 0.96-0.96), and creatinine (77.50%; 95%CI, 2.27-2.63). CONCLUSION: GFR calculated by the 6-variable MDRD equation may be closer to the true GFR than that calculated by the CKD-EPI equation.

关键词： Chronic Kidney Disease Epidemiology Col-laboration Estimated glomerular filtration rate Livercirrhosis Modification of Diet in Renal Disease Renalfunction

Potential effects of sea level rise on the soil-atmosphere green-house gas emissions in Kandelia obovata mangrove forests

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Acta Oceanologica Sinica 2023年第4期42卷 25-32页

作者： Jiahui chen Shichen Zeng Min Gao Guangcheng chen Heng Zhu Yong Ye Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems College of the Environment and EcologyXiamen UniversityXiamen 361102China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Fujian Provincial Station for Field Observation and Research of Island and Coastal Zone in Zhangzhou Xiamen 361005China

Mangrove forests are under the stress of sea level rise(SLR)which would affect mangrove soil *** soils are important sources of soil-atmosphere greenhouse gas(GHG)emissions,including carbon dioxide(CO_(2)),methane(CH_(4))and nitrous oxide(N_(2)O).Understanding how SLR influences GHG emissions is critical for evaluating mangrove blue carbon *** this study,potential effects of SLR on the GHG emissions were quantified through static closed chamber technique among three sites under different intertidal elevations,representing tidal flooding situation of SLR values of 0 cm,40 cm and 80 cm,*** with Site SLR 0 cm,annual CO_(2) and N_(2)O fluxes decreased by approximately 75.0%and 27.3%due to higher soil water content,lower salinity and soil nutrient environments at Site SLR 80 ***,CH_(4) fluxes increased by approximately 13.7%at Site SLR 40 cm and 8.8%at Site SLR 80 cm because of lower salinity,higher soil water content and soil ***_(2)-equivalent fluxes were 396.61 g/(m^(2)·a),1423.29 g/(m^(2)·a)and 1420.21 g/(m^(2)·a)at Sites SLR 80 cm,SLR 40 cm and SLR 0 cm,*** Site SLR 0 cm to Site SLR 80 cm,contribution rate of N_(2)O and CH_(4) increased by approximately 7.42%and 3.02%,while contribution rate of CO_(2) decreased by approximately 10.44%.The results indicated that warming potential of trace CH_(4) and N_(2)O was non-negligible with *** effects of SLR on the mangrove blue carbon capability should warrant attention due to changes of all three greenhouse gas fluxes with SLR.

关键词： carbon dioxide methane nitrous oxide CO_(2)-equivalent fluxes sea level rise mangrove forest