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Modeling the effect of stand and site characteristics on the probability of mistletoe infestation in Scots pine stands using remote sensing data
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作者 Luiza Tymińska-Czabańska Piotr Janiec +5 位作者 Pawel Hawrylo Jacek Slopek Anna Zielonka Pawel Netzel Daniel Janczyk Jaroslaw Socha 《Forest Ecosystems》 SCIE CSCD 2024年第3期296-306,共11页
Over the past decade,the presence of mistletoe(Viscum album ssp.austriacum)in Scots pine stands has increased in many European countries.Understanding the factors that influence the occurrence of mistletoe in stands i... Over the past decade,the presence of mistletoe(Viscum album ssp.austriacum)in Scots pine stands has increased in many European countries.Understanding the factors that influence the occurrence of mistletoe in stands is key to making appropriate forest management decisions to limit damage and prevent the spread of mistletoe in the future.Therefore,the main objective of this study was to determine the probability of mistletoe occurrence in Scots pine stands in relation to stand-related endogenous factors such as age,top height,and stand density,as well as topographic and edaphic factors.We used unmanned aerial vehicle(UAV)imagery from 2,247 stands to detect mistletoe in Scots pine stands,while majority stand and site characteristics were calculated from airborne laser scanning(ALS)data.Information on stand age and site type from the State Forest database were also used.We found that mistletoe infestation in Scots pine stands is influenced by stand and site characteristics.We documented that the densest,tallest,and oldest stands were more susceptible to mistletoe infestation.Site type and specific microsite conditions associated with topography were also important factors driving mistletoe occurrence.In addition,climatic water balance was a significant factor in increasing the probability of mistletoe occurrence,which is important in the context of predicted temperature increases associated with climate change.Our results are important for better understanding patterns of mistletoe infestation and ecosystem functioning under climate change.In an era of climate change and technological development,the use of remote sensing methods to determine the risk of mistletoe infestation can be a very useful tool for managing forest ecosystems to maintain forest sustainability and prevent forest disturbance. 展开更多
关键词 Generalized additive models Tree infestation Mistletoe occurrence ALS UAV Scots pine
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Aging Mongolian pine plantations face high risks of drought-induced growth decline:evidence from both individual tree and forest stand measurements
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作者 Mingyong Li Leilei Yang +2 位作者 Yu Cao Dedong Wu Guangyou Hao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期109-120,共12页
Discerning vulnerability differences among different aged trees to drought-driven growth decline or to mortality is critical to implement age-specific countermeasures for forest management in water-limited areas.An im... Discerning vulnerability differences among different aged trees to drought-driven growth decline or to mortality is critical to implement age-specific countermeasures for forest management in water-limited areas.An important species for afforestation in dry environments of northern China,Mongolian pine(Pinus sylvestris var.mongolica Litv.)has recently exhibited growth decline and dieback on many sites,particularly pronounced in old-growth plantations.However,changes in response to drought stress by this species with age as well as the underlying mechanisms are poorly understood.In this study,tree-ring data and remotely sensed vegetation data were combined to investigate variations in growth at individual tree and stand scales for young(9-13 years)and aging(35-52 years)plantations of Mongolian pine in a water-limited area of northern China.A recent decline in tree-ring width in the older plantation also had lower values in satellited-derived normalized difference vegetation indices and normalized difference water indices relative to the younger plantations.In addition,all measured growth-related metrics were strongly correlated with the self-calibrating Palmer drought severity index during the growing season in the older plantation.Sensitivity of growth to drought of the older plantation might be attributed to more severe hydraulic limitations,as reflected by their lower sapwood-and leaf-specific hydraulic conductivities.Our study presents a comprehensive view on changes of growth with age by integrating multiple methods and provides an explanation from the perspective of plant hydraulics for growth decline with age.The results indicate that old-growth Mongolian pine plantations in water-limited environments may face increased growth declines under the context of climate warming and drying. 展开更多
关键词 Tree age Drought stress Mongolian pine plantation Tree rings Remote sensing Plant hydraulics
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The variation in basal channels and basal melt rates of Pine Island Ice Shelf
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作者 Mingliang Liu Zemin Wang +2 位作者 Baojun Zhang Xiangyu Song Jiachun An 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期22-34,共13页
In recent years,there has been a significant acceleration in the thinning,calving and retreat of the Pine Island Ice Shelf(PIIS).The basal channels,results of enhanced basal melting,have the potential to significantly... In recent years,there has been a significant acceleration in the thinning,calving and retreat of the Pine Island Ice Shelf(PIIS).The basal channels,results of enhanced basal melting,have the potential to significantly impact the stability of the PIIS.In this study,we used a variety of remote sensing data,including Landsat,REMA DEM,ICESat-1 and ICESat-2 satellite altimetry observations,and Ice Bridge airborne measurements,to study the spatiotemporal changes in the basal channels from 2003 to 2020 and basal melt rate from 2010 to 2017 of the PIIS under the Eulerian framework.We found that the basal channels are highly developed in the PIIS,with a total length exceeding 450 km.Most of the basal channels are ocean-sourced or groundingline-sourced basal channels,caused by the rapid melting under the ice shelf or near the groundingline.A raised seabed prevented warm water intrusion into the eastern branch of the PIIS,resulting in a lower basal melt rate in that area.In contrast,a deepsea trough facilitates warm seawater into the mainstream and the western branch of the PIIS,resulting in a higher basal melt rate in the main-stream,and the surface elevation changes above the basal channels of the mainstream and western branch are more significant.The El Ni?o event in 2015–2016 possibly slowed down the basal melting of the PIIS by modulating wind field,surface sea temperature and depth seawater temperature.Ocean and atmospheric changes were driven by El Ni?o,which can further explain and confirm the changes in the basal melting of the PIIS. 展开更多
关键词 pine Island Ice Shelf basal channel basal melt rate digital elevation models(DEMs) satellite altimetry
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Pteropine Orthoreovirus(PRV7S)does not Establish Persistent Infection in NP460 Cells but with Inflammatory Response Triggered
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作者 LOH Mun Khin Alson SIEW Zhen Yun +4 位作者 LEONG Pooi Pooi KOH Rhun Yian CHYE Soi Moi WONG Siew Tung VOON Kenny 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第9期886-891,共6页
Pteropine orthoreovirus(PRV)is a nonenveloped double-stranded RNA(dsRNA)virus of the genus Orthoreovirus under the family Reoviridae.The PRV genome is composed of 10 dsRNA segments,including three large(L)segments,thr... Pteropine orthoreovirus(PRV)is a nonenveloped double-stranded RNA(dsRNA)virus of the genus Orthoreovirus under the family Reoviridae.The PRV genome is composed of 10 dsRNA segments,including three large(L)segments,three medium(M)segments,and four small(S)segments surrounded by an icosahedral capsid[1]. 展开更多
关键词 PRV pine REOVIRUS
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Response of soil bacterial community to biochar application in a boreal pine forest
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作者 Yan Ge Xiao-li Li +6 位作者 Marjo Palviainen Xuan Zhou Jussi Heinonsalo Frank Berninger Jukka Pumpanen Kajar Köster Hui Sun 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期749-759,共11页
Boreal forests commonly suff er from nitrogen defi ciency due to low rate of nitrogen mineralization.Biochar may promote soil organic matter decomposition and accelerate nitrogen mineralization.In this study,Illumina ... Boreal forests commonly suff er from nitrogen defi ciency due to low rate of nitrogen mineralization.Biochar may promote soil organic matter decomposition and accelerate nitrogen mineralization.In this study,Illumina NovaSeq sequencing combined with functional annotation of prokaryotic taxa(FAPROTAX)analysis was used to investigate the eff ect of biochar pyrolysis temperatures,the amount of applied biochar,and the period since the biochar application(2-and 3-year)on soil bacterial communities.The results show that biochar pyrolysis temperatures(500℃ and 650℃)and the amount of applied biochar(0.5 kg m^(−2)and 1.0 kg m^(−2))did not change soil properties.Nevertheless,the interaction of biochar pyrolysis temperature and the amount had signifi cant eff ects on bacterial species richness and evenness(P<0.05).The application of biochar produced at 500℃ had a lower abundance of Actinobacteria and Verrucomicrobia,while that produced at 650℃ had a higher abundance of Conexibacter and Phenylobacterium.When biochar produced at 650℃ was applied,applying 0.5 kg m^(−2)had a higher abundance of Cyanobacteria,Conexibacter,and Phenylobacterium than that of 1.0 kg m^(−2)(P<0.05).Functionally,the abundance of the aromatic compound degradation group increased with the extension of application time and increase of pyrolysis temperature.The time since application played an important role in the formation of soil bacterial communities and their functional structure.Long-term studies are necessary to understand the consequence of biochar on bacterial communities in boreal forests. 展开更多
关键词 Biochar application Bacterial communities Community function Boreal pine forests
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Changes in the growth of Scots pine(Pinus sylvestris L.)stands in an urban environment in European Russia since 1862
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作者 Aleksandr V.Lebedev 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1279-1287,共9页
A century and a half ago,in the European part of Russia(Moscow),forest scientists established the first long-term observations of forests,many of which are under observation to the present day.In the twentieth century... A century and a half ago,in the European part of Russia(Moscow),forest scientists established the first long-term observations of forests,many of which are under observation to the present day.In the twentieth century,climate changes and,due to industrial development,forest areas were under air pollution.Based on observations from 157 sites,this study shows that the growth and density of Scots pine(Pinus sylvestris L.)have decreased by the end of the twentieth century.The environment has changed,and the growth and development of plantations has slowed.Pine yields(-34%stand volume)and their life expectancy(on average 50 years)have decreased.These changes are critical for forestry and for the management of forests in urban centers.Due to the decline in growth,ecosystem functions by urban forests has decreased.In order to increase the sustainability of urban forests and the provision of ecosystem services,it is preferable to create multi-species stands with a complex structure. 展开更多
关键词 Forest stand Scots pine Stand growth Urbanized environment Human footprint
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Effect of acid-associated mechanical pretreatment on the hydrolysis behavior of pine sawdust in subcritical water
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作者 Wei Yang Yalun Ma +6 位作者 Xu Zhang Fan Yang Dong Zhang Shengji Wu Huanghu Peng Zezhou Chen Lei Che 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期195-204,共10页
The effects of sulfuric acid-associated mechanical pretreatment on the hydrolysis behavior of pine sawdust were investigated in this study.Sulfuric acid could act as an acidic catalyst to depolymerize holocellulose th... The effects of sulfuric acid-associated mechanical pretreatment on the hydrolysis behavior of pine sawdust were investigated in this study.Sulfuric acid could act as an acidic catalyst to depolymerize holocellulose through cleavage of the glycosidic bonds,the dissociation energies of which were supplied by the impact of a ball on pine sawdust,during milling.The destruction of glycosidic and hydrogen bonds in pine sawdust resulted in a decrease of crystallinity and an increase of water solubility.The sulfuric acid could promote the hydrolysis of holocellulose and its hydrolysis products.It also destroyed the chemical linkages between holocellulose and lignin during ball milling.The cleavage of chemical linkages with holocellulose made lignin more difficult to hydrolyze in subcritical water,and higher activation energy was needed to hydrolyze pretreated pine sawdust at higher reaction temperatures.It also led to the formation of glucose char and aromatic-linked polymer char from the hydrolysis products of holocellulose. 展开更多
关键词 Acid-associated mechanical pretreatment Subcritical water pine sawdust Hydrolysis behavior Kinetic parameters
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Nail Holding Performance of Self-Tapping Screws on Masson Pine and Chinese Fir Dimension Lumbers
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作者 De Li Bengang Zhang +7 位作者 Yuan Tu Guoming Xiao Meifen Tian Xiaoxue Xu Xiao Zhong Qiaoyan Zhang Zhigang Wu Jiankun Liang 《Journal of Renewable Materials》 EI 2023年第10期3725-3738,共14页
Screw connection is a type most commonly applied to timber structures.As important commercial tree species in China,Masson pine and Chinese fir have the potential to prepare wood structures.In this study,the effects o... Screw connection is a type most commonly applied to timber structures.As important commercial tree species in China,Masson pine and Chinese fir have the potential to prepare wood structures.In this study,the effects of the diameter of the self-tapping screw and the guiding bores on the nail holding performance on different sections of Masson pine and Chinese fir dimension lumbers were mainly explored.The results showed that:(1)The nail holding strength of the tangential section was the maximum,followed by that of the radial section,and that of the cross section was the minimum.(2)The nail holding strength of Masson pine was higher than that of Chinese fir.(3)The nail holding strength grew with the increase in the diameter of self-tapping screws,but a large diameter would lead to plastic cracking of the timber,thus further affecting the nail holding strength.Masson pine and Chinese fir reached the maximum nail holding strength when the diameter of self-tapping screws was 3.5 mm.(4)Under a large diameter of screws,prefabricated guiding bores could mitigate timber cracking and improve its nail holding strength.(5)Prefabricated guiding bores were more necessary for the screw connection of Masson pine.The results obtained could provide a scientific basis for the screw connection design of Masson pine and Chinese fir timber structures. 展开更多
关键词 Masson pine Chinese fir self-tapping screws nail holding performance
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Microwave Drying of Scots Pine Lumber:Structure Changes,Its Effect on Liquid Permeability
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作者 Sheng He Weiqi Leng +4 位作者 Yuhe Chen Hongchen Li Jingpeng Li Zaixing Wu Zizhang Xiao 《Journal of Renewable Materials》 SCIE EI 2023年第1期321-331,共11页
Microwave(MW)drying method was adopted to enhance the liquid permeability of Scots pine lumber.Structure changes were characterized by stereoscope microscope,scanned electron microscope(SEM)and transmission electron m... Microwave(MW)drying method was adopted to enhance the liquid permeability of Scots pine lumber.Structure changes were characterized by stereoscope microscope,scanned electron microscope(SEM)and transmission electron microscope(TEM)examination.Pore parameters before and after MW treatment were detected by mercury intrusion porosimetry(MIP)method,and the effect of structure changes on liquid permeability were analyzed.As stereoscope microscope,SEM and TEM examination results showed,macro and micro checks mainly developed at intercellcular of tracheids,intercellular of ray parenchyma and tracheid,while these checks extend main along the radial-longitudinal plane.Pit border destruction,aspirated pits’orus translocation and micro-checks in tracheid cell wall were also observed.MIP test shown that pore volume and pore area increased as macro and micro checks generated to form new cavities.Microstructure changes would increase the quantity of pores or enlarge the pore diameter.Liquid flow pathways increased as macro and micro checks generated,aspirated pits reopened to form new pathways;liquid flow efficiency improved as porosity,pore volume and pore diameter increased which facilitated the liquid flow. 展开更多
关键词 Microwave drying structure change pore structure liquid permeability Scots pine lumber
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Dynamics of mediterranean pine forests reforested after fires
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作者 Álvaro Enríquez-de-Salamanca 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期345-354,共10页
Forest fires are frequent under a Mediterranean climate and have shaped the landscape of the region but are currently altered by human action and climate change.Fires have historically conditioned the presence of pine... Forest fires are frequent under a Mediterranean climate and have shaped the landscape of the region but are currently altered by human action and climate change.Fires have historically conditioned the presence of pine forests,depending on severity and forest regeneration.Regeneration of Mediterranean pine forests is not always successful,and a transition to shrublands or stands of resprouting species can occur,even after reforestation.This study analyses vegetation changes in two Mediterranean pine forests after severe fires and both reforested.The pines had difficulty to regenerate,even despite post-fire reforestation.The problem is the difficulty of young seedlings to survive,possibly due to increased summer drought.Problems are greater in pine species at the limit of their ecological tolerance:Pinus pinea had a much better recovery success while P.sylvestris and P.nigra virtually disappeared.Pinus pinaster had intermediate results but recovery was generally poor.A transition has taken place in many burnt areas to scrubland or to thickets of the resprouting Quercus rotundifolia,although it is not possible to know whether they will evolve into forests or remain in a sub climatic state.Resprouting species may increase fire severity but facilitates post-fire colonisation.Post-fire recovery difficulties are closely linked to issues of natural regeneration.Fire could initiate the disappearance of pine forests,but even in the absence of fire they may disappear in the long-term due to the lack of regeneration.Action is needed to increase the resilience of these forests,ensuring natural regeneration,and incorporating resprouting species in the understorey. 展开更多
关键词 Mediterranean region pine forests Post-fi re recovery Vegetation dynamics Wildfi re transitions
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The morphological changes of basal channels based on multisource remote sensing data at the Pine Island Ice Shelf
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作者 Xiangyu Song Zemin Wang +2 位作者 Jianbin Song Baojun Zhang Mingliang Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第12期90-104,共15页
The basal channel is a detailed morphological feature of the ice shelf caused by uneven basal melting.This kind of specifically morphology is widely distributed in polar ice shelves.It is an important research object ... The basal channel is a detailed morphological feature of the ice shelf caused by uneven basal melting.This kind of specifically morphology is widely distributed in polar ice shelves.It is an important research object of sea-ice interaction and plays a vital role in studying the relationship between the ice sheet/ice shelf and global warming.In this paper,high-resolution remote sensing image and ice penetration data were combined to extract the basal channel of the Pine Island Ice Shelf.The depth variation of Pine Island Ice Shelf in the recent 20 years was analyzed and discussed by using ICESat-1,ICESat-2,and IceBridge data.Combined with relevant marine meteorological elements(sea surface temperature,surface melting days,circumpolar deep water and wind)to analyze the basal channel changes,the redistribution of ocean heat is considered to be the most important factor affecting the evolution and development of the basal channel. 展开更多
关键词 basal channel pine Island Ice Shelf digital elevation model(DEM) ICESAT IceBridge
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In Situ Generation of Copper Nanoparticles in Heat-Treated Copper-Containing Masson’s Pine as a Preservative Process for Sawn Timber
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作者 Minting Lai Guijun Xie +2 位作者 Wanju Li Lamei Li Yongjian Cao 《Journal of Renewable Materials》 SCIE EI 2023年第6期2665-2678,共14页
Heat-treated wood has good dimensional stability,durability,and color,but its susceptibility to fungal growth affects its commercial value.In this study,lumber harvested from mature Masson’s pine(Pinus massoniana Lam... Heat-treated wood has good dimensional stability,durability,and color,but its susceptibility to fungal growth affects its commercial value.In this study,lumber harvested from mature Masson’s pine(Pinus massoniana Lamb.)was vacuum impregnated with a basic copper salt solution(copper hydroxide,diethanolamine,and polyethylene glycol 200)prior to heat-treatment at 220℃ for 3 h.Antifungal properties,surface chemistry,crystal structure and sugar contents were tested,compared with heat treatment alone.The results showed that the samples treated by heating without copper salt treatment showed poor suppression of fungal growth,the copperimpregnated heat-treated wood suppressed(100%)the growth of Botryodiplodia theobromae Pat.,Aspergillus niger V.Tiegh.,Penicillium citrinum Thom,and Trichoderma viride Pers.The combined results of X-ray photoelectron spectroscopy,X-ray diffraction and sugars analysis suggested that fungal inhibition by the heat-treated copper-bearing Masson’s pine was mainly due to the reduction of the metal salt by PEG200 at high temperature to generate copper nanoparticles.In addition,the reduced sugar content of the treated timber,and hence the nutrient substrate for spoilage microbes,reduced in the presence of the metal salts at high-temperature.This study has demonstrated an effective method of increasing low-grade wood’s utility and commercial value. 展开更多
关键词 Heat treatment Masson’s pine sawn timber inhibition of fungal growth copper nanoparticles
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Analysis of Influencing Factors of Pine Wood Nematode Disease in Lu an City Based on GIS
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作者 Juanjuan HU Hao SONG +5 位作者 Gao LIU Yongquan CHENG Yehan YAN Xianrong WANG Xianbin SUN Bangxing HAN 《Plant Diseases and Pests》 CAS 2023年第4期11-17,共7页
[Objectives]The paper was to figure out the distribution of Monochamus alternatus in the stumps of pine wood nematode infected wood in Lu'an City and to provide a theoretical and practical basis for differentiated... [Objectives]The paper was to figure out the distribution of Monochamus alternatus in the stumps of pine wood nematode infected wood in Lu'an City and to provide a theoretical and practical basis for differentiated prevention and control of pine wood nematode disease in the future.[Methods]The factors influencing the number of epidemic small classes and infected plants in all counties and districts of Lu'an City were analyzed by GIS method,and the number of worms and wormholes of M.alternatus inside and outside the stumps of pine wood nematode infected wood in Lu'an City were investigated on the spot.[Results]There were 98,40,54,781,193,268 and 34 epidemic small classes of pine wood nematode disease,and 7241,6099,9532,39161,11079,49876 and 4853 infected plants in Yu'an District,Jin'an District,Yeji District,Shucheng County,Huoshan County,Jinzhai County and Huoqiu County,respectively.Pine wood nematode disease in Lu'an City mostly occurred in Huoshan County,Shucheng County and Jinzhai County,with relatively high altitude,paddy soil,the annual precipitation higher than 2062 mm,and the annual average temperature lower than 16.2℃.The number of diseased plants of pine wood nematode disease was positively correlated with altitude and annual precipitation,and was negatively correlated with annual average temperature.The number of worms and wormholes in pine wood nematode infected wood was very small at different altitudes,stump heights and stump diameters.[Conclusions]The pine wood nematode infected wood can be differentially processed after stump treatment,and stumps can be peeled.The results will provide a theoretical and practical basis for differentiated prevention and control of pine wood nematode disease in the future. 展开更多
关键词 GIS pine wood nematode disease Influencing factor Control measure Lu'an City
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甘肃产不同品种松针的抗氧化活性研究
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作者 刘东彦 石晓峰 +2 位作者 王信 马趣环 沈薇 《林产工业》 北大核心 2024年第1期39-44,共6页
以甘肃产白皮松、雪松、油松、落叶松、樟子松和华山松6个树种的松针为研究对象,采用DPPH法、ABTS法和铜离子还原能力测定其不同浓度乙醇提取物的体外抗氧化活性,并采用熵值法综合评价遴选出抗氧化活性强的松针资源,为松针的进一步开发... 以甘肃产白皮松、雪松、油松、落叶松、樟子松和华山松6个树种的松针为研究对象,采用DPPH法、ABTS法和铜离子还原能力测定其不同浓度乙醇提取物的体外抗氧化活性,并采用熵值法综合评价遴选出抗氧化活性强的松针资源,为松针的进一步开发利用提供参考。研究表明:采用不同浓度乙醇提取时,40%乙醇提取物的抗氧化活性最好;不同品种松针中,雪松松针的抗氧化活性最好,其中天水产雪松松针40%乙醇提取物的评分最高达99.52%,表明其可以作为进一步研究松针抗衰老研究的资源。 展开更多
关键词 松针 不同浓度乙醇提取物 抗氧化活性 熵值法 综合评价
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HPLC-DPPH法评价雪松松针抗氧化活性成分
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作者 戴晓雁 沈薇 +1 位作者 张燕 赵艳萍 《中国药房》 CAS 北大核心 2024年第16期1998-2001,共4页
目的评价雪松松针抗氧化活性成分。方法以维生素C(VC)和没食子酸为阳性对照,采用高效液相色谱(HPLC)法测定1,1-二苯基-2-苦肼基(DPPH)溶液加入雪松松针抗氧化活性成分后DPPH峰面积的衰减情况,并通过计算DPPH自由基的清除率和半数抑制浓... 目的评价雪松松针抗氧化活性成分。方法以维生素C(VC)和没食子酸为阳性对照,采用高效液相色谱(HPLC)法测定1,1-二苯基-2-苦肼基(DPPH)溶液加入雪松松针抗氧化活性成分后DPPH峰面积的衰减情况,并通过计算DPPH自由基的清除率和半数抑制浓度(IC_(50)),来评价雪松松针3种有效部位及8个单体成分的抗氧化活性。采用Agilent Eclipse Plus-C_(18)(250 mm×4.6 mm,5μm)为色谱柱,乙腈-水(62∶38,V/V)为流动相;检测波长为517 nm;流速为1.0 mL/min;柱温为25℃;进样量为20μL。结果雪松松针各有效部位清除DPPH自由基活性的能力大小依次为总黄酮>总多酚>总木脂素,IC_(50)分别为76.10、100.50、115.40μg/mL。与阳性对照比较,除山柰酚-3-O-β-D-葡萄糖苷外,7个单体化合物清除DPPH自由基活性的能力大小依次为二氢杨梅素>金丝桃苷>原儿茶酸>没食子酸>阿魏酸>杨梅素>山柰酚-3-O-(6″-O-E-阿魏酰基)-β-D-吡喃葡萄糖苷>VC>异鼠李素,IC50分别为16.50、19.40、23.73、27.24、32.10、32.20、47.60、93.20、297.20μg/mL。结论建立了HPLC-DPPH法用于评价雪松松针抗氧化活性;雪松松针具有较强的抗氧化活性,其中有效部位总黄酮、总多酚及单体成分二氢杨梅素、金丝桃苷等是具有开发前景的纯天然抗氧化剂。 展开更多
关键词 雪松松针 抗氧化活性 有效部位 化学成分 HPLC-DPPH
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灰葡萄孢寄生菌Clpse01的杀线活性研究
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作者 徐勇 彭子嘉 +4 位作者 徐正梅 邵雅坤 蓝燕 徐清华 余仲东 《中国生物防治学报》 CSCD 北大核心 2024年第1期186-195,共10页
在用灰葡萄孢菌Botrytis cinerea培养松材线虫的过程中,发掘了一株具有杀线活性的灰葡萄孢寄生菌Clpse01。本文在光学显微镜下对菌株Clpse01的形态和其对灰葡萄孢菌的生长影响进行了观察;采用ITS4/ITS5、LR5/LR0R、Bt2a/Bt2b和EF1-688F/... 在用灰葡萄孢菌Botrytis cinerea培养松材线虫的过程中,发掘了一株具有杀线活性的灰葡萄孢寄生菌Clpse01。本文在光学显微镜下对菌株Clpse01的形态和其对灰葡萄孢菌的生长影响进行了观察;采用ITS4/ITS5、LR5/LR0R、Bt2a/Bt2b和EF1-688F/EF1-1251R引物进行了分子生物学鉴定;同时测试了菌株Clpse01对松材线虫的杀线活性及对松材线虫卵孵化能力和繁殖能力的影响;最后测试了菌株Clpse01的胞外蛋白浓度,胞外β-葡萄糖苷酶活性和胞外几丁质酶活性。根据形态学和分子生物学结果,将菌株Clpse01鉴定为假卡鲁卡枝惠霉Clonostachyspseudochroleuca。菌株Clpse01可以缠绕、侵入灰葡萄孢菌的菌丝以获得营养来源,使灰葡萄孢菌的菌丝生长受到抑制。将2000条松材线虫接种到长满菌株Clpse01的培养基上,8 d后仅分离出6条/皿活线虫,而对照灰葡萄孢菌培养基上分离的线虫数为33066条/皿活线虫;菌株Clpse01发酵液处理松材线虫48 h后的校正死亡率为88%,浓度为1×108孢子/mL的孢子悬液处理松材线虫24 h后的校正死亡率为88.33%;菌株Clpse01 2×稀释发酵液24 h对卵的孵化抑制率为100%。发酵培养6 h后,菌株Clpse01胞外蛋白浓度为1782.917μg/mL,胞外β-葡萄糖苷酶为9.99 U/mL,胞外几丁质酶含量为0.8792U/mL,并随发酵时间推移而升高。菌株Clpse01通过寄生松材线虫的食物来源灰葡萄孢菌和影响松材线虫的繁殖、存活和卵的孵化起作用,胞外β-葡萄糖苷酶、几丁质酶是毒杀松材线虫的两个重要生理因子。 展开更多
关键词 松材线虫 灰葡萄孢菌 假卡鲁卡枝惠霉 寄生真菌 生防真菌
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北美黄杉和云杉-松木-冷杉平行弦木桁架承载性能比较
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作者 强明礼 肖鹏 +4 位作者 袁哲 苏艳炜 朱浪 秦鑫悦 杜官本 《林业科学》 EI CAS CSCD 北大核心 2024年第4期147-156,共10页
【目的】对比不同腹杆角度下北美黄杉和云杉-松木-冷杉(SPF)华伦式平行弦木桁架的承载性能,探究腹杆角度和结构用材对华伦式平行弦木桁架承载性能的影响规律,为平行弦木桁架结构设计提供理论依据。【方法】以承载力和稳定性为验算指标,... 【目的】对比不同腹杆角度下北美黄杉和云杉-松木-冷杉(SPF)华伦式平行弦木桁架的承载性能,探究腹杆角度和结构用材对华伦式平行弦木桁架承载性能的影响规律,为平行弦木桁架结构设计提供理论依据。【方法】以承载力和稳定性为验算指标,利用Smsolver结构力学求解器对平行弦木桁架各杆件的内力变化及其变形情况进行定量分析,得到平行弦木桁架腹杆角度的上、下临界角度和最优腹杆角度;采用ABAQUS有限元软件对3种腹杆角度的北美黄杉和SPF平行弦木桁架进行有限元模型分析与验证,获得不同基材平行弦木桁架在不同腹杆角度情况下的内力变化规律,判断其可能的破坏形式和受力机理;以SPF和北美黄杉为基材分别制作3种腹杆角度的平行弦木桁架,进行抗弯承载性能静力试验,探究平行弦木桁架的极限荷载、应力分布及主要破坏形式,并与有限元模拟结果进行对比,验证平行弦木桁架有限元模型分析的准确性和适用性。【结果】1)华伦式平行弦木桁架的最优腹杆角度为47°,下临界角度为34°,上临界角度为60°;2)北美黄杉平行弦木桁架的极限荷载范围为26.53~40.83 kN,跨中挠度范围为30.57~31.01 mm,SPF平行弦木桁架的极限荷载范围为23.48~34.16 kN,跨中挠度范围为31.85~32.05 mm;3)腹杆角度34°、47°、60°的北美黄杉和SPF平行弦木桁架极限荷载分别为26.53和23.48 kN、35.10和30.06 kN、40.83和34.16 kN,对应跨中挠度分别为31.85和31.01 mm、30.72和32.05 mm、30.57和31.97 mm;4)北美黄杉平行弦木桁架的破坏形式主要表现为靠近桁架支座处的腹杆出现裂纹以及桁架端部或荷载施加点处齿板拔出,SPF平行弦木桁架的破坏形式主要表现为桁架端部和荷载施加点处齿板拔出;5)ABAQUS有限元模拟和试验验证发现,2种平行弦木桁架跨中处弦杆轴力最大,往两边逐次递减,桁架跨中处腹杆轴力最小,往两边逐次递增,且弦杆轴力大于腹杆。【结论】北美黄杉平行弦木桁架承载性能优于SPF平行弦木桁架;平行弦木桁架的承载性能随腹杆角度增加而增加;2种平行弦木桁架的薄弱点均为桁架端部和荷载施加点处的齿板连接节点;ABAQUS有限元模型能有效反映出平行弦木桁架受力分布和整体结构变形趋势。 展开更多
关键词 平行弦木桁架 北美黄杉 云杉-松木-冷杉 腹杆角度 承载性能 ABAQUS有限元模拟
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UPLC-MS/MS法检测3种食品中松仁过敏原
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作者 宁亚维 周泓鑫 +4 位作者 杨正 马俊美 刘茁 张岩 李强 《食品科学》 EI CAS CSCD 北大核心 2024年第1期247-253,共7页
基于食品基质中松仁过敏原Pin k 2建立了一种超高效液相色谱-串联质谱法。将松仁经过研磨、脱脂、浸提、酶解后经Easy-nLC 1000-QExactive高分辨质谱仪进行分离分析,结合Uniprot蛋白数据库以及ProteinPilotTM软件对质谱图进行数据处理,... 基于食品基质中松仁过敏原Pin k 2建立了一种超高效液相色谱-串联质谱法。将松仁经过研磨、脱脂、浸提、酶解后经Easy-nLC 1000-QExactive高分辨质谱仪进行分离分析,结合Uniprot蛋白数据库以及ProteinPilotTM软件对质谱图进行数据处理,经BLAST验证特异性,最终筛选3条松仁特异性肽段。方法学验证结果表明,方法在0.001~50mg/mL范围内线性关系良好,定量限为1mg/kg;在饼干、巧克力和饮料3种空白基质中的平均回收率为88.50%~107.57%,相对标准偏差不高于6.08%,基质效应为89.77%~96.13%。该方法具有灵敏度高、特异性好的优势,可应用于饼干、巧克力、饮料等食品样品中松仁过敏原的检测,为我国食品标签真实性检验及食品中隐性过敏原的检测提供技术支持。 展开更多
关键词 松仁 过敏原 超高效液相色谱-串联质谱法 检测
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美国Spruce Pine与新疆阿尔泰地区高纯石英伟晶岩的对比研究 被引量:27
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作者 张晔 陈培荣 《高校地质学报》 CAS CSCD 北大核心 2010年第4期426-435,共10页
对美国北卡罗来纳州Spruce Pine地区白岗岩/伟晶岩和新疆阿尔泰白云母花岗岩/伟晶岩进行了对比研究。这两个地区的伟晶岩可能是过铝质花岗岩浆通过熔体-蒸汽分异作用的产物。美国产高纯石英的伟晶岩发育在片岩、片麻岩的背景之上,主要... 对美国北卡罗来纳州Spruce Pine地区白岗岩/伟晶岩和新疆阿尔泰白云母花岗岩/伟晶岩进行了对比研究。这两个地区的伟晶岩可能是过铝质花岗岩浆通过熔体-蒸汽分异作用的产物。美国产高纯石英的伟晶岩发育在片岩、片麻岩的背景之上,主要造岩矿物中富含斜长石,Na大于K,大离子亲石元素Sr和Ba含量高,高场强元素和稀土元素含量低,Eu正异常,石英中杂质元素含量低。这些特征可作为高纯石英伟晶岩的判别标志。我国阿尔泰地区的伟晶岩脉十分发育,所研究的样品中,有些样品已经具有这些特点,阿尔泰伟晶岩区具有产高纯石英的成矿前景。 展开更多
关键词 伟晶岩 高纯石英 SPRUCE pine 阿尔泰
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抗松材线虫病马尾松种质资源遗传多样性分析及核心种质构建 被引量:2
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作者 邓莉丽 刘青华 +2 位作者 周志春 高凯 骆定会 《浙江农林大学学报》 CAS CSCD 北大核心 2024年第1期67-78,共12页
【目的】对来自安徽省林业科学研究院和异地保存在浙江省临海市林业技术推广和场圃旅游服务总站的114份抗松材线虫Bursaphelenchus xylophilus病马尾松Pinus massoniana种质进行遗传多样性与群体结构分析,构建抗性马尾松核心种质库。【... 【目的】对来自安徽省林业科学研究院和异地保存在浙江省临海市林业技术推广和场圃旅游服务总站的114份抗松材线虫Bursaphelenchus xylophilus病马尾松Pinus massoniana种质进行遗传多样性与群体结构分析,构建抗性马尾松核心种质库。【方法】对114份抗性马尾松种质进行检测,使用分子生物学软件计算遗传多样性参数,并进行主坐标(PCoA)和群体结构分析。利用M策略和随机取样策略分别构建核心种质,分析不同核心种质的的遗传多样性参数,确定最适合的构建方法。【结果】114份抗性马尾松种质共检测到115个等位基因,平均有效等位基因数(N_(e))为5.54,平均Shannon’s多样性指数(I)为1.51,平均多态信息含量(P_(IC))为0.90,结果表明其具有较高的遗传多样性水平。群体结构分析将114份抗性马尾松种质分为4个亚群,主坐标分析结果与上述基本一致。根据遗传多样性参数和抽样数量综合考虑,M策略构建的核心种质能以最小的种质数保留原有种质最大的遗传多样性,为最佳的取样策略。利用该策略得到了72份核心种质,其保留了原有种质100%的等位基因数,N_(e)、I、期望杂合度(H_(e))、PIC等遗传参数的保留率分别为95.67%、94.96%、98.12%和100.00%,将构建的核心种质与原有种质进行t检验、PCoA分析和UPGMA聚类分析,结果表明两者间的遗传多样性无显著差异。【结论】114份抗性马尾松种质遗传多样性水平较高,构建的72份抗性马尾松核心种质,去除了遗传冗余,有利于抗性马尾松种质资源的有效保护和科学利用,可为优异基因发掘和新品种选育提供参考。 展开更多
关键词 马尾松 抗松材线虫病 SSR 遗传多样性 核心种质
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