检索结果-南通市图书馆

Phylotranscriptomic discordance is best explained by incomplete lineage sorting within Allium subgenus Cyathophora and thus hemiplasy accounts for interspecific trait transition

引用

Plant Diversity 2024年第1期46卷 28-38页

作者： Zengzhu Zhang Gang Liu Minjie Li state key laboratory of Herbage Improvement and grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000GansuPR China

The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and *** can be learned about this process from phylogeny-based trait ***,such inference is often plagued by genome-wide gene-tree discordance(GTD),mostly due to incomplete lineage sorting(ILS)and/or introgressive hybridization,especially when the genes underlying the traits appear ***,by collecting transcriptomes,whole chloroplast genomes(cpDNA),and population genetic datasets,we used the coalescent model to turn GTD into a source of information for ILS and employed hemiplasy to explain specific cases of apparent“phylogenetic discordance”between different morphological traits and probable species phylogeny in the Allium *** concatenation and coalescence methods consistently showed the same phylogenetic topology for species tree inference based on single-copy genes(SCGs),as supported by the KS ***,GTD was high across the genomes of ***:~27%e38.9%of the SCG trees were in conflict with the species *** and nuclear incongruence was also *** coalescent simulations indicated that such GTD was mainly a product of *** hemiplasy risk factor calculations supported that random fixation of ancient polymorphisms in different populations during successive speciation events along the *** phylogeny may have caused the character transition,as well as the anomalous cpDNA *** study exemplifies how phylogenetic noise can be transformed into evolutionary information for understanding character state transitions along species phylogenies.

关键词： Hemiplasy Multispecies coalescence Lineage sorting Gene tree discordance Phylotranscriptomics Allium subg.Cyathophora

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of formal credit on pastoral household expense: Evidence from the Qinghai-Xizang Plateau of China

引用

Journal of Integrative Agriculture 2024年第5期23卷 1774-1785页

作者： Yan Zhang Yi Huang Fan Zhang Zeng Tang state key laboratory of Herbage Improvement and grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020China

Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'*** pastoral China,formal financial institutions are gradually ***,a limited understanding remains of how formal credit affects herders'household *** on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive *** results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal *** credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth ***,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household ***,this study suggests that policies should improve herders'accessibility to formal credit.

关键词： formal credit herders expense Qinghai-Xizang Plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

引用

Journal of Forestry Research 2024年第3期35卷 111-130页

作者： Xin Chen Yujun Sun state Forestry&grassland Administration key laboratory of Forest Resources&Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable ***,the potential of GEE for forest resource management has not been fully *** extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast *** and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant *** results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source ***,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was *** terrain factors and removing spatial correlation from NFRI sample points further improved the recognition *** optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE were 83.6%and 80.7%for dominant species extraction,*** high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant *** the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant woody plant species Subtropics Model performance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Conversion of a single-layer ANN to photonic SNN for pattern recognition

引用

Science China(Information Sciences) 2024年第1期67卷 261-270页

作者： Yanan HAN Shuiying XIANG Tianrui ZHANG Yahui ZHANG Xingxing GUO Yuechun SHI state key laboratory of Integrated Service Networks State Key Discipline Laboratory of Wide Bandgap Semiconductor TechnologyXidian University Yongjiang laboratory

This work presents a complete conversion scheme for photonic spiking neural networks(SNNs).We verified that the output of an artificial neural network(ANN) trained with the simulated optical activation function can be directly converted into the spike rate of a photonic spiking neuron *** reveal the feasibility of hardware implementation,we considered the effects of different bit precisions of data and weight,noise level,and bias current mismatch on the converted *** proposed scheme was evaluated using the Deterding vowel,IRIS,TIDIGITS,and MNIST datasets for pattern recognition,and achieved mean accuracies of 95.80%,98.67%,96.19%,and 92.33%,*** proposed scheme can convert an ANN into a photonic SNN with almost no precision loss,and the performance was comparable to that of an ANN trained with the rectified linear unit *** proposed scheme can enable the high-performance implementation of photonic SNNs.

关键词： photonic SNN conversion optical computing pattern recognition artificial neural network

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

The Combination of Achnatherum inebrians Extracts and Soil Microorganisms Inhibited Seed Germination and Seedling Growth in Elymus nutans

引用

Phyton-International Journal of Experimental Botany 2024年第3期93卷 567-580页

作者： Rui Zhang Taixiang Chen Zhenjiang Chen Hao Chen Xuekai Wei Malik Kamran Chunjie Li state key laboratory of Herbage Improvement and grassland Agro-Ecosystems Key Laboratory of Animal Husbandry InnovationMinistry of Agriculture and Rural AffairsEngineering Research Center of Grassland AgricultureMinistry of EducationWest Gansu Province Prataculture Technology Innovation CenterCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou730020China Center for grassland Research National Forestry and Grassland AdministrationCaFBeijing100091China

In a greenhouse experiment,the effects of soil microorganisms and extracts of Achnatherum inebrians on the seed germination and seedling growth of Elymus nutans were *** results showed that both the extracts from aboveground and belowground parts of *** signiﬁcantly inhibited the germination rate,germination potential,germination index,vigor index,seedling height,root length,and fresh weight of ***,but increased malondialdehyde content,catalase,peroxidase and superoxide dismutase activity of *** seedlings(p<0.05).The allelopathy of aqueous extracts of the aboveground parts of *** was stronger than that of the *** extracts of the aboveground parts of *** decreased seed germination rate,germination potential,germination index,vigor index,seedling length,root length,and seedling fresh weight by 10.45%-74.63%,24.18%-32.50%,19.03%-73.36%,37.83%-88.41%,21.42%-53.14%,2.65%-40.21%,and 20.45%-61.36%,respectively,and malondialdehyde content,peroxidase,catalase,and superoxide dismutase activity increased by 8.09%-62.24%,27.83%-86.47%,22.90%-93.17%,and 11.15%-75.91%,*** above indexes were higher in live soil than in sterilized *** microorganisms increased the allelopathy of *** seed germination rate,germination potential,germination index,vigor index,seedling length,and seedling fresh weight of *** planted in live soil decreased by 8.22%-48.48%,10.00%-51.85%,8.19%-53.26%,16.43%-60.03%,12.91%-28.81%,and 9.09%-22.86%compared with sterilized soil,*** content,peroxidase,catalase,and superoxide dismutase activity of *** planted in live soil increased by 53.91%-81.06%,15.71%-57.34%,33.33%-86.31%,and 9.78%-52.51%compared with sterilized soil,*** existence of soil microorganisms enhanced the allelopathy of the secondary metabolites of ***.A combination of microorganisms and aqueous extracts from the aboveground parts of *** had the s

关键词： Achnatherum inebrians water immersion liquid aqueous leachate precipitate allelopathy Elymus nutans soil microorganisms

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China

引用

Plant Diversity 2024年第3期46卷 353-361页

作者： Jingya Zhang Cui Xiao Xiaoyu Duan Xin Gao Hao Zeng Rong'an Dong Gang Feng Keping Ma Ministry of Education key laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia key laboratory of grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China state key laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection *** study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory *** Forest models were then used to find the most parsimonious multivariate *** results showed that interannual variation in specimen number between 1900 and 2020 was *** number of these species in southeast China was notably lower than that in northwest *** range and geographical range of species had significant positive correlations with specimen *** addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal *** findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting *** correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate.

关键词： Biological specimen Collection preference Dominant plant species Environmental range Geographical range Species traits

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Wall temperature effects on the stability of leeward vortices of a blunt inclined cone

引用

Acta Mechanica Sinica 2024年第7期40卷 29-42页

作者： Ligeng Zhang Bingbing Wan Siwei Dong Jianqiang Chen Xi Chen state key laboratory of Aerodynamics Mianyang 621000China

Streamwise vortex instability is one of the most potent mechanisms for the transition of the three-dimensional boundary *** using the global stability analysis methods,stability characteristics of the leeward vortex over a blunt cone with an angle of attack under a typical wind tunnel condition are studied and are compared to the case with a smaller wall temperature ratio(corresponding to a flight condition).The vortical structure features inward and outward vortices,similar to that in the flight *** the flight condition,the outward vortices appear stronger than the inward vortices,resulting in stronger outer-mode *** the inner mode is heavily stabilized compared to the flight condition,it can still radiate apparent *** acoustic sources are computed based on Lighthill's acoustic analogy,showing that the entropy term measuring the deviation from the isentropic relation is *** Mack second mode is shown to most likely trigger the transition in the flight condition,it is absent in the wind tunnel condition,and a shear-layer mode turns out to be the most dangerous ***,the instability frequencies and growth rates of the wind tunnel case are much smaller than those of the flight case,indicating that wall heating may stabilize the leeward vortices.

关键词： Instability of streamwise vortices Hypersonic boundary layer flow Spatial BiGlobal method PSE3D method

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Wood of trees:Cellular structure,molecular formation,and genetic engineering

引用

Journal of Integrative Plant Biology 2024年第3期66卷 443-467页

作者： Yingying Zhu Laigeng Li state key laboratory of Herbage Improvement and grassland Agro-ecosystems and College of Ecology Lanzhou UniversityLanzhou 730000China National key laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China

Wood is an invaluable asset to human society due to its renewable nature,making it suitable for both sustainable energy production and material ***,wood derived from forest trees plays a crucial role in sequestering a significant portion of the carbon dioxide fixed during photosynthesis by terrestrial ***,with the expansion of the global population and ongoing industrialization,forest coverage has been substantially decreased,resulting in significant challenges for wood production and *** production practices have changed away from natural forests toward plantation ***,understanding the underlying genetic mechanisms of wood formation is the foundation for developing high-quality,fast-growing plantation *** ideal forest trees for wood production using genetic technologies has attracted the interest of *** studies have been carried out in recent years on the molecular,genetic,and cell-biological mechanisms of wood formation,and considerable progress and findings have been *** studies and findings indicate enormous possibilities and prospects for tree *** review will outline and assess the cellular and molecular mechanisms of wood formation,as well as studies on genetically improving forest trees,and address future development prospects.

关键词： cambium cell wall Populus wood formation xylem

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Whole-genome resequencing of Hu sheep identifies candidate genes associated with agronomic traits

引用

Journal of Genetics and Genomics 2024年第8期51卷 866-876页

作者： Liming Zhao Lvfeng Yuan Fadi Li Xiaoxue Zhang Huibin Tian Zongwu Ma Deyin Zhang Yukun Zhang Yuan Zhao Kai Huang Xiaolong Li Jiangbo Cheng Dan Xu Xiaobin Yang Kunchao Han Xiuxiu Weng Weimin Wang state key laboratory of Herbage Improvement and grassland Agro-Ecosystems Key Laboratory of Grassland Livestock Industry InnovationMinistry of Agriculture and Rural AffairsEngineering Research Center of Grassland IndustryMinistry of EducationCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhouGansu 730020China Lanzhou Veterinary Research Institute Chinese Academy of Agricultural SciencesLanzhouGansu 730046China College of Animal Science and Technology Gansu Agricultural UniversityLanzhouGansu 730070China

The phenotypic diversity resulting from artificial or natural selection of sheep has made a significant contribution to human *** sheep are a local sheep breed unique to China with high reproductive rates and rapid *** selection signatures have been widely used to investigate the genetic mechanisms underlying phenotypic variation in ***,we conduct whole-genome sequencing of 207 Hu sheep and compare them with the wild ancestors of domestic sheep(Asiatic mouflon)to investigate the genetic characteristics and selection signatures of Hu *** on six signatures of selection approaches,we detect genomic regions containing genes related to reproduction(BMPR1B,BMP2,PGFS,CYP19,CAMK4,GGT5,and GNAQ),vision(ALDH1A2,SAG,and PDE6B),nervous system(NAV1),and immune response(GPR35,SH2B2,PIK3R3,and HRAS).Association analysis with a population of 1299 Hu sheep reveals that those missense mutations in the GPR35(GPR35 g.952651 A>G;GPR35 g.952496 C>T)and NAV1(NAV1 g.84216190 C>T;NAV1 g.84227412 G>A)genes are significantly associated(P<0.05)with immune and growth traits in Hu sheep,*** research offers unique insights into the selection characteristics of Hu sheep and facilitates further genetic improvement and molecular investigations.

关键词： Hu sheep Whole-genome resequencing Selection signature GPR35 NAV1 Single nucleotide polymorphism

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Experimental and numerical demonstration of hierarchical time-delay reservoir computing based on cascaded VCSELs with feedback and multiple injections

引用

Science China(Information Sciences) 2024年第2期67卷 279-290页

作者： Xingxing GUO Shuiying XIANG Xingyu CAO Biling GU state key laboratory of Integrated Service Networks Xidian University state key Discipline laboratory of Wide Bandgap Semiconductor Technology School of MicroelectronicsXidian University

In this paper, we propose and demonstrate experimentally and numerically a hierarchical timedelay optical reservoir computing(RC) system based on cascaded vertical-cavity surface-emitting lasers(VCSELs) with feedback and multiple injections. The prediction performance characteristics of the hierarchical time-delay RC system based on cascaded VCSELs under different reservoir layers are ***, the prediction performance of the hierarchical time-delay RC system is first improved and saturates as the number of reservoir layers increases. Besides, the impacts of key factors on predicting the hierarchical time-delay RC system are also analyzed in detail experimentally and numerically. This proposed hierarchical time-delay RC system based on VCSELs is useful for the further development of RC systems and may be beneficial to improve the ability of RC systems to solve more complex problems.

关键词： vertical-cavity surface-emitting laser reservoir computing neuromorphic photonics time-delay system information processing

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：