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Natural Hybridization between Rhododendron delavayi and R.cyanocarpum(Ericaceae),from Morphological,Molecular and Reproductive Evidence

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Journal of Integrative Plant Biology 2010年第9期52卷 844-851页

作者： yong-peng ma Chang-Qin Zhang Jing-Li Zhang Jun-Bo Yang Kunming Botanic Garden Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China Key Laboratory of Resource Plants and Biotechnology Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China Graduate University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing 100049 China Tunnan Agricultural University Kunming 650201 China Key Laboratory of Biodiversity and Biogeography Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

The natural hybridization that occurs between two sympatric species of Rhododendron subgenus Hymenanthes in Yunnan, China, was investigated. In field observations, it was noted that the putative hybrids between R. delavayi Franch. and R. cyanocarpum （Franch.） Franch. ex W.W. Sm. had intermediate morphologies. On the basis of morphology, chloroplast DNA （trnL-rp132） and nuclear DNA （waxy）, hybrids and parental species were identified. Hybridization occurred in both directions, but was asymmetrical, with R. delavayi as the major maternal parent. Reciprocal hand pollination treatments showed that either species, as pollen donor or pollen receiver, could produce fruits. It was noted that fruit set varied among treatments. The same pollinators （bumblebees） were shared in both parental species. From these results, we conclude that individuals with intermediate morphologies are indeed of hybrid origin from natural hybridization between R. cyanocarpum and R. delavayi. Furthermore, we presume the hybridization at the study site could have been initiated by habitat disturbance in the 1950s, and we may hence witness the early stages of hybrid swarm formation.

关键词： Natural hybridization Hybridization Hybrids Species Fruits DNA Fruit Swarming Pollen Pollinators

Rhododendron kuomeianum(Ericaceae),a new species from northeastern Yunnan(China),based on morphological and genomic data

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Plant Diversity 2021年第4期43卷 292-298页

作者： Yu-Hang Chang Gang Yao Jens Neilsen De-Tuan Liu Lu Zhang yong-peng ma Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China Key Laboratory for Plant Diversity and Biogeography of East Asia Chinese Academy of SciencesKunmingYunnan 650201China Dobbies Garden Centre UK-DD2 PerthScotlandUK Flower Research Institute Yunnan Academy of Agricultural SciencesKunmingYunnan 650051China

Rhododendron kuomeianum Y.H.Chang,J.Nielsen&Y.P.ma,a new species of Rhododendron(Ericaceae)within subsect.maddenia in sect.Rhododendron from Yiliang County,NE Yunnan,China,is described and illustrated.The new species is similar to R.valentinianum,but it can be easily distinguished by its sparse scales on the abaxial surface of the leaf blade,fewer flowers per inflorescence and white corolla with pale red margins.There are also differences in the widths of calyx lobes,leaf blade shape and indumentum characteristics of the petiole between the new species and Rhododendron linearilobum.We confirmed that R.kuomeianum is a new species closely related to R.valentinianum and R.changii with phylogenomic studies of 10 species within this subsection based on restriction site-associated DNA sequencing(RADseq)data.These phylogenomic analyses also clarified additional taxonomic problems in this subsection previously raised by morphological analysis.Our findings make a strong case for using next-generation sequencing to explore phylogenetic relationships and identify new species,especially in plants groups with complicated taxonomic problems.

关键词： Rhododendron New species RAD-seq Phylogenetic position

Genetic diversity and structure of Rhododendron meddianum,a plant species with extremely small populations

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Plant Diversity 2021年第6期43卷 472-479页

作者： Xiu-Jiao Zhang Xiong-Fang Liu De-Tuan Liu Yu-Rong Cao Zheng-Hong Li yong-peng ma Hong ma Research Institute of Resources Insects Chinese Academy of ForestryKunming650224YunnanChina College of Forestry Nanjing Forestry UniversityNanjing210037JiangsuChina Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Kunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina Yunnan Key Laboratory of Plant Reproductive Adaption and Evolutionary Ecology School of Ecology and Environmental ScienceYunnan UniversityKunming 650504YunnanChina

Rhododendron meddianum is a critically endangered species with important ornamental value and is also a plant species with extremely small populations.In this study,we used double digest restriction-siteassociated DNA sequencing(ddRAD)technology to assess the genetic diversity,genetic structure and demographic history of the three extant populations of R.meddianum.Analysis of SNPs indicated that R.meddianum populations have a high genetic diversity(p?0.0772±0.0024,HE?0.0742±0.002).Both FST values(0.1582e0.2388)and AMOVA showed a moderate genetic differentiation among the R.meddianum populations.Meanwhile,STRUCTURE,PCoA and NJ trees indicated that the R.meddianum samples were clustered into three distinct genetic groups.Using the stairway plot,we found that R.meddianum underwent a population bottleneck about 70,000 years ago.Furthermore,demographic models of R.meddianum and its relative,Rhododendron cyanocarpum,revealed that these species diverged about 3.05(2.21e5.03)million years ago.This divergence may have been caused by environmental changes that occurred after the late Pliocene,e.g.,the Asian winter monsoon intensified,leading to a drier climate.Based on these findings,we recommend that R.meddianum be conserved through in situ,ex situ approaches and that its seeds be collected for germplasm.

关键词： Rhododendron meddianum ddRAD Genetic diversity Population demography Conservation implications

Repellent,larvicidal and adulticidal activities of essential oil from Dai medicinal plant Zingiber cassumunar against Aedes albopictus

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Plant Diversity 2021年第4期43卷 317-323页

作者： Ming-Xiang Li yong-peng ma Hong-Xia Zhang Hong-Zheng Sun Hong-Hai Su Sheng-Ji Pei Zhi-Zhi Du Key Laboratory of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming650201China University of Chinese Academy of Sciences Beijing100049China Kunming City Center for Disease Control and Prevention Kunming650034China

Zingiber cassumunar is an important plant used in traditional medicine and as a natural mosquito re-pellent.However,the compounds responsible for the repellent activity of the plant are still unknown.The aim of the study is to identify the components of Z.cassumunar essential oil that show repellent activity against Aedes albopictus.We also evaluated the larvicidal and adulticidal activities of Z.cassumunar essential oil against Ae.albopictus.In-cage mosquito repellent experiments showed that Z.cassumunar essential oil possessed moderate repellent activity with a minimum effective dose(MED)of 0.16±0.01 mg/cm^(20,compared to reference standard N,N-diethyl-3-methylbenzamide(DEET,0.03±0.01 mg/cm^(20).Bioassay-guided fractionation identified the major active compound of Z.cassumunar essential oil as(-)-terpinen-4-ol(1)(MED:0.19±0 mg/cm^(20).We also found that Z.cassumunar essential oil showed moderate larvicidal activity against first instar larvae of Ae.albopictus with a LC50(50%lethal concentration)of 44.9 mg/L after 24 h.Fumigation bioassays showed that Z.cassumunar essential oil exhibits moderate adulticidal activity against Ae.albopictus with a LC50 of 5.44%,while(-)-terpinen-4-ol showed significant adulticidal activity with a LC50 of 2.10%after 24 h.This study verifies that the Z.cassumunar essential oil has mosquito repellent activity,and that(-)-terpinen-4-ol is mainly responsible for this activity.Furthermore,this study provides scientific support for the folk usage of Z.cassumunar essential oil as mosquito repellent and indicates that Z.cassumunar essential oil and(-)-terpinen-4-ol can be used as plant-derived repellents and insecticides for mosquito control.

关键词： Zingiber cassumunar Essential oil Repellent activity Larvicidal activity Adulticidal activity (-)-Terpinen-4-ol

The Extension Dimension of Subcategories and Recollements of Abelian Categories

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Acta mathematica Sinica,English Series 2024年第4期40卷 1042-1058页

作者： Xin ma Ye Yang peng Zhao yong HUANG College of Science Henan University of EngineeringZhengzhou 451191P.R.China Department of mathematics Nanjing UniversityNanjing 210093P.R.China

We investigate the behavior of the extension dimension of subcategories of abelian categories under recollements.LetΛ',Λ,Λ"be art in algebras such that(modΛ',mod A,modΛ")is a recollement,and let D'and D"be subcategories of modΛand modΛ"respectively.For any n,m≥0,under some conditions,we get dimΩ^(k)(D)≤dimΩ^(n)(D')+dimΩ^(m)(D")+1,where k=max{m,n}and D is the subcategory of modΛglued by D'and D";moreover,we give a sufficient condition such that the converse inequality holds true.As applications,some results for Igusa-Todorov subcategories and syzygy finite sub categories are obtained.

关键词： Recollements extension dimension Igusa–Todorov subcategories syzygy finite subcategories

Epigenetic regulation of SARS-Cov-2 spike protein modulates cellular viability and nascent RNA transcription in neuronal cells

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Genes & Diseases 2024年第2期11卷 535-538页

作者： Xi Kong peng Lu Jinyue Zhang Zheng Bao Chenghao Kuang Bingqing Xie Jianhua peng Ning ma yong Jiang Shigang Yin Laboratory of Neurological Diseases and Brain Function The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan 646000China Institute of Epigenetics and Brain Science Southwest Medical UniversityLuzhouSichuan 646000China Department of Neurosurgery The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan 646000China Inflammation and Allergic Diseases Research Unit The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan 646000China

SARS-CoV-2 has been demonstrated to be highly susceptible to neuron-and glial-like cells,1 but there is no consensus regarding how the virus affects neurons following neuroinvasion.It is therefore unknown if and how SARS-CoV-2 maintains the homeostasis of neuronal cells.Herein,we revealed that the receptor-binding domain(RBD)of the SARS-CoV-2 spike protein acted as an extracellular remodeling component to undermine epigenetic regulation,perturbnascentRNA(nsRNA)transcription,promote mitochondrial biogenesis,and increase cellular viability in SH-SY5Y cells.

关键词： invasion homeostasis maintain

Enhanced cyclic stability of partially disordered spinel cathodes through direct fluorination with gaseous fluorine

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Rare Metals 2024年第4期43卷 1635-1646页

作者： yong-Nian ma Ling-Chen Kong Shao-Shan Chen yong Wang Li-Dong Sun Cong peng Meng-Meng Qin Yu Li Wei Feng Tianjin Key Laboratory of Composite and Functional materials School of Materials Science and EngineeringTianjin University Institute of Advanced Technology and Equipment Beijing University of Chemical Technology

Spinel-type cathodes are considered an optimal substitute for conventional layered oxide cathodes owing to their use of inexpensive and earth-abundant manganese as the redox-active element.Moreover,the introduction of cation disorder can effectively suppress the detrimental two-phase reaction to realize high capacities in a wide voltage range.However,the continuous capacity decay during cycles has hindered the widespread application of these cathode materials.Inorganic fluorides exhibit excellent electrochemical stability at high voltage;therefore,in this study,the direct F2 gas reaction with a partially disordered spinel cathode(Li1.6Mn1.6O3.7F0.3,LMOF1.6) was initially applied to investigate the impacts of fluorination on the surface structure and electrochemical performances.The inorganic fluorinated layer,mainly containing LiF,was distributed uniformly on the surface of LMOF1.6nanoparticles after fluorination for an appropriate time without the turbulence caused by the valency of manganese cation,which improved the capacity retention and rate capability by the suppression of structural damage,parasitic reaction,and cation dissolution.The LMOF1.6cathode fluorinated for 0.5 h exhibited a capacity of283.6 mah·g-1at 50 ma·g-1and an enhanced capacity retention of 29.6% after 50 cycles in the voltage range of1.5-4.8 V,as compared to the pristine LMOF1.6 with only27.9% capacity retention.

关键词： Spinel-type cathodes Direct fluorination Capacity retention ability High rate capability

Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： Qian ma peng Jin Frank L.Lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is studied.First,an augmented system is constructed by the tracking error system and reference system.This transformation aims to convert the tracking control prob-lem into a stabilization control problem.Then,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty items.Based on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is developed.Finally,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal controller.The proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety constraints.The performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

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Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng peng Yanming ma Chris J.Pickard Hanyu Liu maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard materials & Key Laboratory of material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of materials Science & Metallurgy University of Cambridge Advanced Institute for materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior