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Modeling the early transmission of COVID-19 in New York and San Francisco using a pairwise network model

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Infectious Disease Modelling 2022年第1期7卷 212-230页

作者： Shanshan feng xiao-feng luo Xin Pei Zhen Jin Mark Lewis Hao Wang Department of Mathematics North University of ChinaTaiyuanShanxi030051China College of Mathematics Taiyuan University of TechnologyShanxiTaiyuan030024China Complex System Research Center Shanxi UniversityTaiyuan030006ShanxiChina Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention Shanxi UniversityTaiyuan030006ShanxiChina Department of Mathematics and Statistics Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada Department of Biological Sciences University of AlbertaEdmontonAlbertaT6G 2E9Canada

Classical epidemiological models assume mass ***,this assumption is violated when interactions are not *** the recent COVID-19 pandemic,and resulting shelter in place social distancing directives,mass action models must be modified to account for limited social *** this paper we apply a pairwise network model with moment closure to study the early transmission of COVID-19 in New York and San Francisco and to investigate the factors determining the severity and duration of outbreak in these two *** particular,we consider the role of population density,transmission rates and social distancing on the disease dynamics and *** analysis shows that there is a strongly negative correlation between the clustering coefficient in the pairwise model and the basic reproduction number and the effective reproduction *** shelter in place policy makes the clustering coefficient increase thereby reducing the basic reproduction number and the effective reproduction *** switching population densities in New York and San Francisco we demonstrate how the outbreak would progress if New York had the same density as San Francisco and *** results underscore the crucial role that population density has in the epidemic *** also show that under the assumption of no further changes in policy or transmission dynamics not lifting the shelter in place policy would have little effect on final outbreak size in New York,but would reduce the final size in San Francisco by 97%.

关键词： COVID-19 Social network Quarantine Social distance Clustering coefficient

Nonpharmaceutical interventions contribute to the control of COVID-19 in China based on a pairwise model

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Infectious Disease Modelling 2021年第1期6卷 643-663页

作者： xiao-feng luo Shanshan feng Junyuan Yang xiao-Long Peng xiaochun Cao Juping Zhang Meiping Yao Huaiping Zhu Michael Y.Li Hao Wang Zhen Jin Department of Mathematics North University of ChinaTaiyuanShanxi030051China Complex System Research Center Shanxi UniversityTaiyuan030006ShanxiChina Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention Shanxi UniversityTaiyuan030006ShanxiChina School of Mathematical Sciences Shanxi UniversityTaiyuan030006ShanxiPR China Department of Mathematics and Statistics York UniversityTorontoONM3J 1P3Canada Department of Mathematics and Statistics Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

Nonpharmaceutical interventions(NPIs),particularly contact tracing isolation and household quarantine,play a vital role in effectively bringing the Coronavirus Disease 2019(COVID-19)under control in *** pairwise model,has an inherent advantage in characterizing those two NPIs than the classical well-mixed ***,in this paper,we devised a pairwise epidemic model with NPIs to analyze COVID-19 outbreak in China by using confirmed cases during February 3rde22nd,*** explicitly incorporating contact tracing isolation and family clusters caused by household quarantine,our model provided a good fit to the trajectory of COVID-19 *** calculated the reproduction number R=1.345(95%CI:1.230-1.460)for Hubei province and R=1.217(95%CI:1.207-1.227)for China(except Hubei).We also estimated the peak time of infections,the epidemic duration and the final size,which are basically consistent with real *** indicated by simulation that the traced high-risk contacts from incubated to susceptible decrease under NPIs,regardless of infected *** sensitivity analysis showed that reducing the exposure of the susceptible and increasing the clustering coefficient bolster COVID-19 *** the enforcement of household quarantine,the reproduction number R and the epidemic prevalence declined ***,we obtained the resumption time of work and production in China(except Hubei)on 10th March and in Hubei at the end of April 2020,respectively,which is broadly in line with the actual *** results may provide some potential lessons from China on the control of COVID-19 for other parts of the world.

关键词： COVID-19 Pairwise epidemic model Household quarantine Clustering coefficient High-risk contacts

Establishment of a nested-ASP-PCR method to determine the clarithromycin resistance of Helicobacter pylori

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World Journal of Gastroenterology 2016年第25期22卷 5822-5830页

作者： xiao-feng luo Jian-Hua Jiao Wen-Yue Zhang Han-Ming Pu Bao-Jin Qu Bing-Ya Yang Min Hou Min-Jun Ji Department of Pathogen Biology Nanjing Medical University Department of Gastroenterology First Affiliated Hospital of Nanjing Medical University Department of Gastroenterology Nanjing Qixia District Hospital

AIM: To investigate clarithromycin resistance positions 2142, 2143 and 2144 of the 23 Sr RNA gene in Helicobacter pylori(H. pylori) by nested-allele specific primer-polymerase chain reaction(nested-ASP-PCR).METHODS: The gastric tissue and saliva samples from 99 patients with positive results of the rapid urease test(RUT) were collected. The nested-ASP-PCR method was carried out with the external primers and inner allele-specific primers corresponding to the reference strain and clinical strains. Thirty gastric tissue and saliva samples were tested to determine the sensitivity of nested-ASP-PCR and ASP-PCR methods. Then, clarithromycin resistance was detected for 99 clinical samples by using different methods, including nestedASP-PCR, bacterial culture and disk diffusion. RESULTS: The nested-ASP-PCR method was successfully established to test the resistance mutation points 2142, 2143 and 2144 of the 23 SrR NA gene of H. pylori. Among 30 samples of gastric tissue and saliva, the H. pylori detection rate of nested-ASP-PCR was 90% and 83.33%, while the detection rate of ASP-PCR was just 63% and 56.67%. Especially in the saliva samples, nested-ASP-PCR showed much higher sensitivity in H. pylori detection and resistance mutation rates thanASP-PCR. In the 99 RUT-positive gastric tissue and saliva samples, the H. pylori-positive detection rate by nested-ASP-PCR was 87(87.88%) and 67(67.68%), in which there were 30 wild-type and 57 mutated strains in gastric tissue and 22 wild-type and 45 mutated strains in saliva. Genotype analysis showed that three-points mixed mutations were quite common, but different resistant strains were present in gastric mucosa and saliva. Compared to the high sensitivity shown by nested-ASP-PCR, the positive detection of bacterial culture with gastric tissue samples was 50 cases, in which only 26 drug-resistant strains were found through analyzing minimum inhibitory zone of clarithromycin. CONCLUSION: The nested-ASP-PCR assay showed higher detectio

关键词： Helicobacter pylori Nested-allele specific primer-polymerase chain reaction Rapid urease test Clarithromycin resistance Drug sensitivity testing

Study on Pollen Chromosome Doubling in Zenjimaru Persimmon

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Agricultural Sciences in China 2003年第3期2卷 304-307,F003页

作者： GU xiao-feng and luo Zheng-rongCollege of Horticulture and Forestry, Huazhong Agricultural University, Wuhan 430070, P.R.China College of Horticulture and Forestry Huazhong Agricultural University Wuhan 430070 P. R. China

The factors influencing pollen chromosome doubling in Zenjimaru persimmon were studied, based on the knowledge of meiosis process of pollen mother cells. The results showed: (1) the suitable concentration of colchicine was 0.3-0. 5%; (2) the best doubling effect could be obtained during the period from the diplotene stage to the diakinasis stage, and the highest proportion was up to 40.6%; (3) considering giant pollen ratio and proportion of staminate-flower collection, the better treating frequency was 3 times; (4) giant pollen, which formed mainly from dyad and had bigger cell nucleus volume, was unreduced and hexaploid.

关键词： Persimmon 2n pollen Chromosome doubling Colchicine Meiosis

Properties of the QCD matter:review of selected results from the relativistic heavy ion collider beam energy scan(RHIC BES)program

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Nuclear Science and Techniques 2024年第12期35卷 274-311页

作者： Jin‑Hui Chen Xin Dong Xiong‑Hong He Huan‑Zhong Huang feng Liu xiao‑feng luo Yu‑Gang Ma Li‑Juan Ruan Ming Shao Shu‑Su Shi Xu Sun Ai‑Hong Tang Ze‑Bo Tang Fu‑Qiang Wang Hai Wang Yi Wang Zhi‑Gang xiao Guan‑Nan Xie Nu Xu Qing‑Hua Xu Zhang‑Bu Xu Chi Yang Shuai Yang Wang‑Mei Zha Ya‑Peng Zhang Yi‑Fei Zhang Jie Zhao Xiang‑Lei Zhu Key Laboratory of Nuclear Physics and Ion‑Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Nuclear Science Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA QMRC Institute of Modern PhysicsChinese Academy of SciencesLanzhouChina Department of Physics and Astrophysics University of CaliforniaLos AngelesCA 90095USA Key Laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China Department of Physics Brookhaven National LaboratoryUptonNY 11973USA Department of Modern Physics University of Science and Technology of ChinaHefeiChina Department of Physics Purdue UniversityWest LafayetteIN 47907USA Department of Engineering Physics Tsinghua UniversityBeijingChina Department of Physics Tsinghua UniversityBeijingChina School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Physics and Particle Irradiation(MOE) Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China Department of Physics Kent State UniversityKentOH 44242USA Institute of Quantum Matter South China Normal UniversityGuangzhou 510006China

In the paper,we discuss the development of the multigap resistive plate chamber time-of-fight(TOF)technology and the production of the solenoidal tracker at RHIC(STAR)TOF detector in China at the beginning of the twenty-frst ***,recent experimental results from the frst beam energy scan program(BES-I)at the Relativistic Heavy Ion Collider(RHIC)pertaining to measurements of collectivity,chirality,criticality,global polarization,strangeness,heavy favor,dilepton and light nuclei productions are reviewed.

关键词： Heavy ion collision Quark-gluon plasma QCD phase diagram Collectivity Chirality Criticality

Lateral habenula as a link between dopaminergic and serotonergic systems contributes to depressive symptoms with Parkinson’s disease

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Lateral habenula as a link between dopaminergic and serotone...

基于Agent和CPN的Web信息传播系统建模研究

中国生理学会第24届全国会员代表大会暨生理学学术大会

作者： xiao feng luo Bei Lin Zhang Lian Hua Piao Ying Ying Yang 赵华 Department of Physiology College of Basic Medical SciencesJilin University 吉林大学

Degeneration of substantia nigra dopaminergic neurons is an important cause of Parkinson’s disease（PD）,and its motor consequences have been widely ***,mood disorders associated with PD have begun to attract attention,however,their pathogenesis remains *** is associated with not only degenerative changes in dopaminergic neurons in the substantia nigra but also changes in serotonergic neurons in the raphe *** addition,abnormalities in central 5-hydroxytryptamine（5-HT）neurotransmission are thought to play a key role in the pathogenesis of *** lateral habenula（LHb）is closely related to the substantia nigra and raphe nuclei,and its hyperactivity is closely related with the pathogenesis of ***,in this study,PD rats were screened for depressive-like behaviors and found that the cytochrome c oxidase（CCO）activity in the LHb of these rats was twice that of control *** the forced swim test（FST）,it was found that LHb lesions decreased depressive-like behavior as indexed by decreased immobility times and increased climbing ***,LHb lesions enhanced 5-HT levels in the raphe nuclei as measured by high-performance liquid chromatography（HPLC）.These results suggest that LHb lesions improve depressive-like behavior in PD rats by increasing 5-HT levels in the raphe ***,the LHb contributes to the depressive-like behavior with PD via mediating the effects of dopaminergic neurons in the substantia nigra on serotonergic neurons in the raphe nuclei.

关键词： Later habenula 6-hydropamine rat model Depressive-like behavior Dorsal raphe nucleus

来源： cnki会议评论

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系统仿真学报 2010年第3期22卷 715-719页

作者：贺筱媛胡晓峰罗批国防大学信息作战与指挥训练教研部北京100091

Web信息传播问题的复杂性是系统宏观结构和微观个体行为两方面因素共同作用的结果。在分析Web信息传播建模难点及解决思路的基础上,研究了将基于Agent的仿真方法和Petri网的描述机制相结合,利用Petri网擅长描述系统的整体逻辑结构和动... 详细信息

Web信息传播问题的复杂性是系统宏观结构和微观个体行为两方面因素共同作用的结果。在分析Web信息传播建模难点及解决思路的基础上,研究了将基于Agent的仿真方法和Petri网的描述机制相结合,利用Petri网擅长描述系统的整体逻辑结构和动态特性的优长,将Agent对系统个体特性和交互规则的仿真溶入到着色Petri网(CPN)描述的系统动态行为之中,使仿真分析和逻辑结构分析结合起来,对解决类似的复杂社会系统仿真提供一种新的思路。

关键词：复杂网络信息传播建模方法 CPN Agent建模

Synergistically enhanced ORR and HER performance on Co-N-C coupled in-situ generated PtCo intermetallic

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Journal of Energy Chemistry 2025年第1期100卷 721-729页

作者： Guanyu luo Min Song Lulu An xiao Huang Qian Zhang Chenhao Zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of Co atomic sites and in-situ generated PtCo intermetallic compounds （IMCs）(o-PtCo@CoNC) is proposed through Co pre-anchoring and subsequent impregnation-reduction *** loading of Co atoms provides a chance for in-situ generating PtCo ordered intermetallic *** remaining Co single atoms and PtCo IMCs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt Co IMCs and Co single atoms,o-PtCo@CoNC exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-PtCo@CoNC delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMCs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Electrolytic reduction

Imperatorin Is Responsible for the Vasodilatation Activity of Angelica Dahurica var. Formosana Regulated by Nitric Oxide in an Endothelium-Dependent Manner

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Chinese Journal of Integrative Medicine 2009年第6期15卷 442-447页

作者：聂红孟兰贞周玖瑶樊晓峰罗勇张广文 College of Pharmacy Jinan University Guangzhou University of Chinese Medicine Research Center for Analytical Sciences of Northeastern University College of Science and Engineering Jinan University

Objective:To demonstrate the vasodilatation activity of the coumarin-containing Angelica dahurica *** and to further analyze active components in the herb ***:(1) The vasodilatation effects induced by different extracts(cyclohexane,ethyl acetate,acetone,methanol,95%ethanol and water) of Angelica dahurica *** on mouse thoracic aorta pre-contracted with phenylephrine were investigated. (2) The amount of imperatorin and isoimperatorin in each extract was measured by high-perfor...

关键词： Angelica dahurica var.formosana thoracic aorta vasodilatation imperatorin isoimperatorin high-performance liquid chromatography