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Influence of voxel size on forest canopy height estimates using full-waveform airborne LiDAR data

Forest Ecosystems 2020年第3期7卷 392-403页

作者： Cheng Wang Shezhou Luo Xiaohuan Xi Sheng Nie dan.ma Youju Huang College of Resources and Environment Fujian Agriculture and Forestry UniversityFuzhou350002China Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing100094China Guangxi Zhuang Autonomous Region Institute of Natural Resources Remote Sensing Nanning530023China

Background: Forest canopy height is a key forest structure parameter. Precisely estimating forest canopy height is vital to improve forest management and ecological modelling. Compared with discrete-return LiDAR(Light Detection and Ranging), small-footprint full-waveform airborne LiDAR(FWL) techniques have the capability to acquire precise forest structural information. This research mainly focused on the influence of voxel size on forest canopy height ***: A range of voxel sizes(from 10.0 m to 40.0 m interval of 2 m) were tested to obtain estimation accuracies of forest canopy height with different voxel sizes. In this study, all the waveforms within a voxel size were aggregated into a voxel-based LiDAR waveform, and a range of waveform metrics were calculated using the voxelbased LiDAR waveforms. Then, we established estimation model of forest canopy height using the voxel-based waveform metrics through Random Forest(RF) regression *** and conclusions: The results showed the voxel-based method could reliably estimate forest canopy height using FWL data. In addition, the voxel sizes had an important influence on the estimation accuracies(R2 ranged from 0.625 to 0.832) of forest canopy height. However, the R2 values did not monotonically increase or decrease with the increase of voxel size in this study. The best estimation accuracy produced when the voxel size was 18 m(R2= 0.832, RMSE = 2.57 m, RMSE% = 20.6%). Compared with the lowest estimation accuracy, the R2 value had a significant improvement(33.1%) when using the optimal voxel size. Finally, through the optimal voxel size, we produced the forest canopy height distribution map for this study area using RF regression model. Our findings demonstrate that the optimal voxel size need to be determined for improving estimation accuracy of forest parameter using small-footprint FWL data.

关键词： Voxel size Airborne LiDAR Full-waveform Forests Canopy height

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Recent Advances in Bio-Inspired Versatile Polydopamine Platforms for “Smart” Cancer Photothermal Therapy

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Chinese Journal of Polymer Science 2023年第5期41卷 699-712,I0007页

作者： Zhi-Yuan ma dan-Ya Li Xin Jia Rui-Li Wang Mei-Fang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan School of Chemistry and Chemical EngineeringShihezi UniversityShihezi 832003China

Although photothermal therapy(PTT)has been developed for fighting cancers,the degradative,toxic,and metabolic nature of photothermal conversion materials(PCMs)has prevented them from being clinically *** advantage of the surface modification strategy of mussel-inspired dopamine chemistry and its excellent photothermal conversion effect,polydopamine(Pdop)represents a versatile PTT platform,providing strategies and methods for the construction of novel Pdop-functionalized *** to its adhesion and secondary reactivity,Pdop can be deposited on virtually all substrates to improve their bioavailability and ***-based PCMs could not be only functionalized with small biomolecules via chemical bonds and/or noncovalent force but also modified with functional polymers via either the“grafting to”or“grafting from”*** review highlights the synthetic methods,therapeutic strategies,and designs of PCMs based on Pdop in recent years to explore its scope and limitations.

关键词： Polydopamine Photothermal therapy Drug delivery systems Polymers Tumor theranostics

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Identification and Expression of TOP3αin Gerbera hybrida

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Horticultural Plant Journal 2021年第2期7卷 167-173页

作者： Shenchong Li Ying Cheng dan Sun Lulin ma Mingyang Li Fan Li College of Horticulture and Landscape Architecture Southwest UniversityChongqing 400715China Key Laboratory for Flower Breeding of Yunnan Province National Engineering Research Center for Ornamental HorticultureFloriculture Research InstituteYunnan Academy of Agricultural SciencesKunming 650200China School of Agriculture Yunnan UniversityKunming 650504China

Meiotic recombination and the resulting novel allele combinations are fundamental to plant breeding and the identification of superior ***,the rate of meiotic crossovers is naturally suppressed below its potential ability,which prevents plant breeding *** suppressors of meiotic recombination have been identified in the model plant Arabidopsis and in other crop *** in these genes can lead to increased recombination frequency and could therefore potentially be used to create hyper-recombinant lines for ornamental *** Gerbera hybrida,the anti-crossover factors remain *** this study,we isolated and cloned TOP3αfrom flower buds of ***,and it encoded 935 amino acids with three conserved domains TOPRIM,TOP1Ac and ***,TOP3αwas the highest expressed at the flower bud stage,which coincided with the occurrence of meiotic recombination,suggesting that TOP3αis associated with the regulation of meiotic recombination in ***.

关键词： Gerbera hybrida meiotic recombination TOP3α gene expression ornamental breeding

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Microstructure Characteristic and Electrochemical Corrosion Behavior of Surface Nano-crystallization Modified Carbon Steel

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Journal of Iron and Steel Research International 2016年第12期23卷 1281-1289页

作者： Zhao-jun CHENG dan SONG Jin-yang JIANG Jing-hua JIANG Xiao-long ma Kai YOU Ai-bin ma College of Mechanics and materials Hohai UniversityNanjing 210098JiangsuChina School of materials Science and Engineering Southeast UniversityNanjing 211100JiangsuChina Suqian Research Institute of Hohai University Suqian 223800JiangsuChina Department of material Science and Engineering North Carolina State UniversityRaleigh 27606US

The surface nano-crystallization （SNC） of carbon steel was achieved via a high-speed rotating wire-brush- ing process. Microstructure characteristics of SNC steel were systematically studied. The SNC steel surface exhibited marked deformed plastic flows and high surface roughness. Due to the accumulated strains, a deformed gradient lay er with thickness of 40-50 μm was produced, and the grain size of the topmost zone was about 50-100 nm. X-ray photoelectron spectroscopy （XPS） analysis indicated that enhanced Fe oxides and Cr oxides were generated. Electrochemical corrosion tests, including open circuit potential （OCP）, electrochemical impendence spectroscopy （EIS）, potentiodynamic polarization （PDP） and potentiostatic polarization （PP） were conducted to study the corrosion be- havior of SNC steel in 3.5 mass% NaC1 solution, where an improved corrosion resistance was observed. The resulted improvement resulted from the dominated positive effects （the attached Cr alloying element and enhanced oxide film） against the negative effects （the higher roughness and the improved corrosion activity of surface microstructure）.

关键词： surface nano-crystallization carbon steel microstructure electrochemical corrosion behavior

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Thermal entanglement in a spin-1/2 Ising-Heisenberg butterfly-shaped chain with impurities

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Chinese Physics B 2020年第11期29卷 212-218页

作者： Meng-Ru ma Yi-dan Zheng Zhu mao Bin Zhou Department of Physics Hubei UniversityWuhan 430062China

We investigate the effect of impurities on the thermal entanglement in a spin-1/2 Ising-Heisenberg butterfly-shaped chain,where four interstitial Heisenberg spins are localized on the vertices of a rectangular plaquette in a unit *** using the transfer-matrix approach,we numerically calculate the partition function and the reduced density matrix of this *** bipartite thermal entanglement between different Heisenberg spin pairs is quantified by the *** also discuss the fluctuations caused by the impurities through the uniform distribution and the Gaussian *** the effects of the external magnetic field,temperature,Heisenberg and Ising interactions as well as the parameter of anisotropy on the thermal entanglement,our results show that comparing with the case of the clean model,in both the twoimpurity model and the impurity fluctuation model the entanglement is more robust within a certain range of anisotropic parameters and the region of the magnetic field where the entanglement occurred is also larger.

关键词： thermal entanglement Ising–Heisenberg butterfly-shaped chain impurities transfer-matrix approach

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Stabilization of a class of Networked Switched Fuzzy Systems

Stabilization of a class of Networked Switched Fuzzy Systems

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第25届中国控制与决策会议

作者： Jie Wang dan.ma Jinming Luo Jun Zhao State Key Laboratory of Synthetical Automation for Process Industries Northeastern University

ISBN: (纸本)9781467355339

In this paper, we study a class of networked switched fuzzy systems, which switched plants with the controllers connected by limited bandwidth communication channels, network induced delay and packet dropout happened inevitably. Using the parallel distributed compensation （PDC） method, we design a switched fuzzy controller to stabilize the closed-loop system. Meanwhile, free-weighting matrix has been taken to deal with the delay and packet dropout cased by network. Finally, a numerical example is given to demonstrate the effectiveness of the proposed approach.

关键词： Switched fuzzy systems networked induced delay stabilization free-weighting matrix.

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A LAMP-assay-based specific microbiota analysis reveals community dynamics and potential interactions of 13 major soybean root pathogens

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Journal of Integrative Agriculture 2020年第8期19卷 2056-2063页

作者： YE Wen-wu ZENG dan-dan XU Miao YANG Jin ma Jia-xin WANG Yuan-chao ZHENG Xiao-bo Department of Plant Pathology Nanjing Agricultural UniversityNanjing 210095P.R.China Key Laboratory of Integrated management of Crop Diseases and Pests Ministry of EducationNanjing 210095P.R.China

Soybean root diseases are associated with numerous fungal and oomycete pathogens;however,the community dynamics and interactions of these pathogens are largely *** performed 13 loop-mediated isothermal amplification(LAMP)assays that targeted specific soybean root pathogens,and traditional isolation assays.A total of 159 samples were collected from three locations in the Huang-Huai-Hai region of China at three soybean growth stages(30,60,and 90 days after planting)in *** LAMP results,we found that pathogen communities differed slightly among locations,but changed dramatically between soybean growth *** sojae,Rhizoctonia solani,and Fusarium oxysporum were most frequently detected at the early stage,whereas Phomopsis longicolla,Fusarium equiseti,and Fusarium virguliforme were most common in the later *** samples(86%)contained two to six pathogen ***,the less detectable species tended to exist in the samples containing more detected species,and some pathogens preferentially co-occurred in diseased tissue,including ***–***–*** and ***–Calonectria ilicicola,implying potential interactions during *** LAMP detection results were confirmed by traditional isolation *** isolated strains exhibited different virulence to soybean,further implying a beneficial interaction among some pathogens.

关键词： soybean root disease fungal and oomycete plant pathogens soil-borne and seed-borne pathogens LAMP assay complex infection

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17α-Ethynylestradiol biodegradation in different river-based groundwater recharge modes with reclaimed water and degradation-associated community structure of bacteria and archaea

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Journal of Environmental Sciences 2018年第2期30卷 51-61页

作者： Weifang ma Jiaji Sun Yangyao Li Xiaoxiu Lun dan Shan Chao Nie Miaomiao Liu College of Environmental Science and Engineering Beijing Forestry University Beijing 100083 China Friendship Center for Environmental Protection Beijing 100029 China Department of Civil and Environmental Engineering university of Illinois at Urbana-Champaign Urbana IL 61801-2352 USA

This study investigated 17α-ethynylestradiol（EE2） biodegradation process and primary metabolic pathways associated with community structures of microorganism during groundwater recharge using reclaimed water. The attenuation rate is 1.58 times higher in wetting and drying alternative recharge（WDAR） than in continual recharge（CR）. The primary biotransformation pathways of EE2 in WDAR system began with the oxidation of C-17 on ring D to form a ketone group, and D-ring was subsequently hydroxylated and cleaved. In the CR system, the metabolic pathway changed from the oxidation of C-17 on ring D to hydroxylation of C-4 on ring A, and ring A or B subsequently cleaved; this transition was related to DO, and the microbial community structure. Four hundred fifty four pyrosequencing of 16 s r RNA genes indicated that the bacterial communities in the upper layer of the WDAR system were more diverse than those found in the bottom layer of the CR system; this result was reversed for archaea. Unweighted Uni Frac and taxonomic analyses were conducted to relate the change in bacterial community structure to the metabolic pathway. Microorganism community diversity and structure were related to the concentrations of dissolved oxygen, EE2 and its intermediates in the system. Five known bacterial classes and one known archaeal class, five major bacterial genera and one major archaeal genus might be involved in EE2 degradation. The findings of this study provide an understanding of EE2 biodegradation in groundwater recharge areas under different recharging modes and can facilitate the prediction of the fate of EE2 in underground aquifers.

关键词： EE2 Biodegradation Groundwater recharge Microbial community and diversity Metabolic intermediates

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Recovery of vanadium and molybdenum from spent petrochemical catalyst by microwave-assisted leaching

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International Journal of Minerals,Metallurgy and materials 2019年第1期26卷 33-40页

作者： Zhi-yuan ma Yong Liu Ji-kui Zhou Mu-dan Liu Zhen-zhen Liu Guangdong Institute of Resources Comprehensive Utilization Guangdong Academy of Sciences State Key Laboratory of Separation and Comprehensive Utilization of Rare Metals Guangdong Provincial Key Laboratory of Development and Comprehensive Utilization of Mineral Resources

The study of the leaching of vanadium(V) and molybdenum(Mo) from spent petrochemical catalysts in sodium hydroxide(NaO H) medium was performed using two approaches, namely, conventional leaching and microwave-assisted leaching methods. The influence of microwave power, leaching time, leaching temperature, and NaOH concentration on the leaching efficiency of spent petrochemical catalyst was investigated. Under microwave-assisted conditions(600 W, 10 min, 90°C, 2.0 mol·L^(-1) NaOH, and 0.20 g·mL^(-1) solid–liquid ratio), the leaching efficiencies of V and Mo reached 94.35% and 96.23%, respectively. It has been confirmed that microwave energy has considerable potential to enhance the efficiency of the leaching process and reduce the leaching time. It is suggested that the enhancement of the leaching efficiencies of V and Mo can be attributed to the existence of a thermal gradient between solid and liquid and the generation of cracks on the mineral surface.

关键词： microwave spent petrochemical catalyst vanadium molybdenum

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Noninvasive genetics provides insights into the population size and genetic diversity of an Amur tiger population in China

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Integrative Zoology 2016年第1期11卷 16-24页

作者： dan WANG Yibo HU Tianxiao ma Yonggang NIE Yan XIE Fuwen WEI Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

Understanding population size and genetic diversity is critical for effective conservation of endangered *** Amur tiger(Panthera tigris altaica)is the largest felid and a flagship species for wildlife *** to habitat loss and human activities,available habitat and population size are continuously ***,little is known about the true population size and genetic diversity of wild tiger populations in *** this study,we collected 55 fecal samples and 1 hair sample to investigate the population size and genetic diversity of wild Amur tigers in Hunchun National Nature Reserve,Jilin Province,*** the samples,we determined that 23 fecal samples and 1 hair sample were from 7 Amur tigers:2 males,4 females and 1 individual of unknown ***,2 fecal samples that were presumed to be from tigers were from Amur leopards,highlighting the significant advantages of noninvasive genetics over traditional methods in studying rare and elusive *** from this sample suggested that the genetic diversity of wild Amur tigers is much lower than that of Bengal tigers,consistent with previous ***,the genetic diversity of this Hunchun population in China was lower than that of the adjoining subpopulation in southwest Primorye Russia,likely due to sampling *** the small population size and relatively low genetic diversity,it is urgent to protect this endangered local subpopulation in China.

关键词： felid genetic diversity noninvasive genetics Panthera tigris altaica population size

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