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Effects of drought on non-structural carbohydrates and C,N,and P stoichiometric characteristics of Pinus yunnanensis seedlings

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Journal of forestry Research 2024年第1期35卷 90-102页

作者： Zhijuan Zhao Lina Wang Yuanxi Liu Jianli Sun Jiandong Xiao Qiong Dong Lianfang Li Wanjie Zhang Chao Wang Junwen Wu College of forestry Southwest Forestry UniversityKunming 650224YunnanPeople’s Republic of China

To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,light and moderate and severe drought treatments[(80±5),(65±5),(50±5),and(35±5)%of field water-holding capacity].Non-structural carbohydrates,carbon(C),nitrogen(N),and phosphorus(P)concentrations were measured in each plant component.The results show that:(1)With increasing drought,non-structural carbohydrates gradually increased in leaves,stems,and coarse roots,while gradually decreased in fine roots;(2)C concentrations of all were relatively stable under different stress levels.Phosphorous utilization of each component increased under light and moderate drought conditions,while N and P utilization efficiency of each plant component decreased under severe drought.Growth was mainly restricted by N,first decreasing and then increasing with increased drought;(3)There was a correlation between the levels of non-structural carbohydrates and C,N,and P in each component.Changes in N concentration affected the interconversion between soluble sugar and starch,which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates;and,(4)Plasticity analysis showed that P.yunnanensis seedlings responded to drought mainly by altering starch concentration,the ratio of soluble sugar to starch in leaves and stems,and further by alter-ing N and P utilization efficiencies.Overall,these results suggest that the physiological activities of all organs of P.yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs.Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P.yunnanensis seedlings.

关键词： Pinus yunnanensis seedlings Drought Non-structural carbohydrates C,N,P stoichiometric characteristics

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The Identification of Phenylalanine Ammonia-Lyase(PAL)Genes from Pinus yunnanensis and an Analysis of Enzyme Activity in vitro

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 503-516页

作者： Dejin Mu Lin Chen Heze Wang Zhaoliu Hu Sihui Chen Shi Chen Nianhui Cai Yulan Xu Junrong Tang Key Laboratory of National forestry and Grassland Administration on Biodiversity Conservation in southwest China Southwest Forestry UniversityKunming650224China College of forestry Southwest Forestry UniversityKunming650224China

Phenylalanine ammonia lyase(PAL)is the rate-limiting and pivotal enzyme of the general phenylpropanoid path-way,but few reports have been found on PAL genes in Pinus yunnanensis.In the present study,three PAL genes were cloned and identiﬁed from P.yunnanensis seedlings for theﬁrst time,namely,PyPAL-1,PyPAL-2,and PyPAL-3.Our results indicated that the open-reading frames of PyPAL genes were 2184,2157,and 2385 bp.Phylogenetic tree analysis revealed that PyPALs have high homology with other known PAL genes in other plants.In vitro enzymatic analysis showed that all three PyPAL recombinant proteins could catalyze the deamination of L-phenylalanine to form trans-cinnamic acid,but only PAL1 and PAL2 can catalyze the conversion of L-tyrosine toρ-coumaric acid.Three PyPAL genes were expressed in different tissues in 1-year-old P.yunnanensis,and such genes had different expression patterns.This study lays a foundation for further understanding of the biosynthesis of secondary metabolites in P.yunnanensis.

关键词： Pinus yunnanensis phenylalanine ammonia-lyase enzyme activity in vitro functional analysis secondary metabolites

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Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM

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Journal of Mountain Science 2024年第6期21卷 2025-2042页

作者： WANG Yanxia YANG Lisha HUANG Xiaoyuan ZHOU Ruliang School of Soil and Water Conservation Southwest Forestry UniversityKunming 650224China School of Economics and Management Southwest Forestry UniversityKunming 650224China

Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate system.Fast and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental issues.This paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended changes.First,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM data.It fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell size.Second,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 m.Then,the NSHTI strips were parameterized through raster vectorization and spatial analysis.Taking Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward uplift.Also,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting depth.Additionally,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 m.The result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources.

关键词： High temperature increase Mountain areas MODIS Spatial pattern recognition Raster window measurement Threshold selection

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Effects of Different Light Qualities on the Growth Characteristics of Populus trinervis

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 1043-1056页

作者： Jiaqi Li Zhensheng Qiao Dan Zong Chengzhong He Key Laboratory for Forest Genetics and Tree Improvement and Propagation in Universities of Yunnan Province Southwest Forestry UniversityKunmingChina Key Laboratory of Biodiversity Conservation in southwest China State Forestry AdministrationSouthwest Forestry UniversityKunmingChina Key Laboratory for forestry Resources Conservation and Utilization in the southwest Mountains of China Ministry of EducationSouthwest Forestry UniversityKunmingChina

Populus trinervis is native to China and plays an irreplaceable role in maintaining the ecological balance of boreal and temperate forests.P.trinervis mainly grows in high-altitude areas.At present,there are limited studies on the response of P.trinervis to different light qualities,so it is necessary to investigate the photosynthetic physiological changes of P.trinervis in different light environments.In our study,P.trinervis was grown for 8 months under light filtered by three different colored films.The three treatments were blue film,green film,and white plastic film.The effects of blue(B),green(G),and white(W)light on photosynthetic pigment content,absolute growth,photosynthetic parameters,soluble sugar content,and chlorophyll fluorescence parameters were studied,respectively.Compared to the Wtreatment,the chlorophyll a and b,carotenoids,total chlorophyll content(a+b),absolute growth of seedling height,net photosynthetic rate(PN),water use efficiency(WUE),total soluble sugars,sucrose,and nonphotochemical quenching(NPQ)of P.trinervis were significantly increased under B treatment.Meanwhile,chlorophyll a and b,carotenoids,total chlorophyll(a+b),transpiration rate(Tr),intercellular CO2 concentration(Ci),stomatal conductance(gs),absolute growth of seedling height and leaf length,reducing sugar,total soluble sugar content,and NPQ were significantly increased under G treatment.The results showed that the absolute growth and chlorophyll content of P.trinervis were increased under B light,while the sugar and photosynthetic parameters were increased under G light.Additional studies may look into how B light impacts absolute growth and promotional mechanisms,as well as how G light affects the accumulation of sugar levels.

关键词： Blue light green light white light photosynthetic pigment soluble sugar

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Development and parentage analysis of SNP markers for Chestnut-vented Nuthatch(Sitta nagaensis)based on ddRAD-seq data

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Avian Research 2024年第2期15卷 271-278页

作者： Qingmiao Yuan Xi Lu Ruixin Mo Xianyin Xu Xu Luo Yubao Duan Key Laboratory for Conserving Wildlife with Small Populations in Yunnan Southwest Forestry UniversityKunming 650224China Key Laboratory for Forest Resources Conservation and Utilization in the southwest Mountains of China Ministry of EducationSouthwest Forestry UniversityKunming 650224China Key Laboratory of Forest Disaster Warning and Control of Yunnan Province Southwest Forestry UniversityKunming 650224China College of forestry Southwest Forestry UniversityKunming 650224China Administration of Zixi Mountain Provincial Nature Reserve Chuxiong 675008China

Extra-pair paternity(EPP)is commonly found in socially monogamous birds,especially in small passerine birds,and there are interspecific and intraspecific variations in the extent of EPP.The Chestnut-vented Nuthatch(Sitta nagaensis)is a socially monogamous passerine bird,and verifying whether this species has EPP relies on parentage testing-S.nagaensis is not known to have EPP.In this study,we developed SNP markers of this species that are informative for parentage analysis from double digest restriction site-associated DNA sequencing(ddRAD-seq)data.A panel consisting of 50 SNP markers,with a mean heterozygosity of 0.343,was used to resolve 95% of nestlings to fathers.The combined exclusion probabilities for the first parent and second parent were 0.991 and 0.9999,respectively.This panel of SNP markers is a powerful tool for parentage assignments in S.nagaensis.In addition,we found that three offspring(7.9%)from three nests(23.1%)were the result of extra-pair fertilization out of 38 offspring in 13 nests.Our study provided information on parentage analysis that has not been reported before in S.nagaensis.It also supplemented the understudied EPP behavior of birds in Asia,contributing to a general understanding of the EPP behaviors of birds.

关键词： Chestnut-vented Nuthatch ddRAD sequencing Extra-pair paternity Parentage analysis SNPs

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Seismic response of a mid-story isolated structure considering SSI in mountainous areas under long-period earthquakes

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 151-161页

作者： Wan Feng Qin Shengwu Liu Dewen Zhao Tiange Zheng Yanping Shan Hang Li Zhiang Peng Fusong Xu Jingran Lei Min College of Construction Engineering Jilin UniversityChangchun 130015China College of Civil Engineering Southwest Forestry UniversityKunming 650024China College of civil engineering Southwest Jiaotong UniversityChengdu 610031China

At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures.

关键词： SSI in mountainous areas long-period earthquakes mid-story isolated structure structural dynamic analysis

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UV-Shielding and Catalytic Characteristics of Nanoscale Zinc-Cerium Oxides

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Journal of Wuhan university of Technology(Materials Science) 2007年第4期22卷 622-625页

作者：柴希娟 School of Science and Interior Design Southwest Forestry University

Fine particles of zinc-cerium oxides （ZCO） used as an ultraviolet filter were prepared via combustion synthesis route. The catalytic activity, UV-shielding performance, surface modification and application of ZCO in polyester varnish were discussed in detail. The experimental results indicate that the photo-catalytic activity of ZCO is much smaller than these of ZnO and TiO2; the oxidation catalytic activity of ZCO is far lower than that of CeO2; the ZCO has shown excellent ultraviolet absorption in the range of UV; addition modified ZCO （MZCO） into polyester will enhance the UV-shielding capability of polyester.

关键词： nanoscale zinc-cerium oxides photo-catalysis oxidation catalysis UV-shielding ability surface modification

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Preparation and gastrointestinal release characteristics of zein / Houttuynia cordata flavonoids composite nanoparticles

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Jingxi Huagong/Fine Chemicals 2024年第6期41卷 1345-1353 and 1361页

作者： Jiang, Yuxin Fan, Fangyu Chen, Cheng Sun, Xue Liu, Jiongna College of Life Science Southwest Forestry University Yunnan Kunming 650224 China Key Laboratory of National forestry and Grassland Administration on Biodiversity Conservation in southwest China Yunnan Kunming 650224 China Key Laboratory of Forest Disaster Warning and Control of Yunnan Province Yunnan Kunming 650224 China College of forestry Southwest Forestry University Yunnan Kunming 650224 China

In order to improve the stability of Houttuynia cordata flavonoids (HCF), Zein/HCF composite nanoparticles were synthesized from zein (Zein) and HCF by anti-solvent method and characterized for structural analysis. The effects of zein and HCF mass ratio on the composite nanoparticles were further investigated. The results showed that there were intermolecular forces, including hydrogen bonding, hydrophobic and electrostatic interactions, between HCF and zein. When m(Zein)∶m(HCF)=20∶3, Zein/HCF composite nanoparticles exhibited the best performance with the highest melting temperature reaching 85.09 ℃, 12.84 ℃ higher than that of Zein nanoparticles (72.25 ℃), its microstructure uniformly dispersed in a spherical shape with the smallest average particle size and polydispersity index (PDI), the narrowest particle size distribution, and the largest absolute Zeta potential value as well as HCF encapsulation rate. In addition, the composite nanoparticles exhibited higher 1,1-diphenyl-2-picrylhydrazyl and diammonium 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radicals scavenging ability, and better heat treatment protection ability by improving the heating stability of HCF. In the simulated gastrointestinal digestion process, the HCF release rate was only 22.31% after 120 min of digestion by simulated gastric fluid (SGF) and reached 75.66% after 120 min of digestion by simulated intestinal fluid (SIF). The HCF release trends in the simulated gastrointestinal fluid were all consistent with the Ritger-Peppas model, but the release mechanisms were different, with a non-Fick diffusion mechanism in SGF while a Fick diffusion mechanism in SIF. © 2024 Fine Chemicals. All rights reserved.

关键词： Nanoparticles

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Advancements in synthetic and electrocatalytic exploitation of guest-host intercalated 2D materials

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Progress in Natural Science:Materials International 2024年第3期34卷 454-469页

作者： Qian Yang Kun Wang Meiling Zhang Feihong Du Jiayang Li Chen Zheng Jinyang Li School of Chemistry Southwest Jiaotong University Yibin Institute of southwest Jiaotong university

The emergence and development of layered materials have shown great promise for many applications, especially in recent years, the effective modulation of the physicochemical properties of layered materials by intercalation chemistry has led to great potential in material design. In this paper, we review the reaction mechanisms of different guest species(metal atoms/ions, organic molecules/ions, inorganic molecules and inorganic ions)intercalated into the host layered materials as well as the recent progress. It is also reviewed that layered intercalated materials with controllable structure and tunable physicochemical properties can be prepared through the occurrence of interactions between different subjects and guests. The specific applications of intercalation chemistry in the field of electrocatalysis, such as the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction and other electrocatalytic reactions, are then discussed, with emphasis on the mechanism of the improved catalytic activity and stability of the layered materials after guest intercalation.

关键词： Electrocatalysis Guest species Intercalation chemistry Layered materials

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Doppler-resilient waveform design in integrated MIMO radar-communication systems

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Science China(Information Sciences) 2024年第1期67卷 187-202页

作者： Zhengchun ZHOU Bing LIU Bingsheng SHEN Avik Ranjan ADHIKARY Pingzhi FAN Institute of Mobile Communications Southwest Jiaotong University Department of Mathematics Southwest Jiaotong University

In recent years,the increased high-rate wireless services(5G and 6G) and reliable sensing capabilities(automotive radar,air traffic control,geophysical monitoring),have led to more serious spectrum congestion.Conventionally,radars and communication systems are often seen to be “competing” for the same resources.In this scenario,an integrated platform for radar and communication systems seems to be an optimal solution to address the problem.In this paper,we propose a preamble waveform design based on zero-correlation zone(ZCZ) and zero odd-correlation zone(ZOCZ) sequence sets,which are Doppler resilient in multiple-input,multiple-output(MIMO) radar.The preamble waveforms can be simultaneously used for channel estimation and radar sensing in RadCom systems.The ambiguity function of the proposed waveforms displays low/zero sidelobes within a time-delay correlation zone.Finally,we give some numerical results to show the efficiency of the proposed waveforms in radar sensing and channel estimation.

关键词： ambiguity function correlation channel estimation integrated radar and communication (RadCom) systems MIMO radar zero correlation zone (ZCZ) sequence set zero odd-correlation zone (ZOCZ) sequence set

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