This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a disti...This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary structure.This approach capitalizes on the boundary’s capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the line.During internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring lines.Conversely,for faults external to the line,the energy is lower compared to adjacent lines.EWT is employed to decompose the collected fault current signals,allowing access to the high-frequency transient energy.The longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the boundary.Moreover,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances.展开更多
The difficulty of effectively monitoring and managing the environment to conserve biodiversity is as yet an unsolved conundrum.A project of the Chinese Academy of Sciences has concluded that progress can be made throu...The difficulty of effectively monitoring and managing the environment to conserve biodiversity is as yet an unsolved conundrum.A project of the Chinese Academy of Sciences has concluded that progress can be made through the use of flagship species selected using criteria drawn from conservation biology,ecosystem function,socio-economics,and cultural importance.Inclusion of the latter three criteria will help attract and maintain the commitment of the public to play full parts in carrying out any conservation measures needed.A system is proposed for scoring species to select those that are most suitable as flagships.This method can be used regardless of the size of the area chosen for attention,whether it is a region,a country,or a particular protected area.展开更多
Structural information of grassland changes on the Tibetan Plateau is essential for understanding alterations in critical ecosystem functioning and their underlying drivers that may reflect environmental changes.Howev...Structural information of grassland changes on the Tibetan Plateau is essential for understanding alterations in critical ecosystem functioning and their underlying drivers that may reflect environmental changes.However,such information at the regional scale is still lacking due to methodological limitations.Beyond remote sensing indicators only recognizing vegetation productivity,we utilized multivariate data fusion and deep learning to characterize formation-based plant community structure in alpine grasslands at the regional scale of the Tibetan Plateau for the first time and compared it with the earlier version of Vegetation Map of China for historical changes.Over the past 40 years,we revealed that(1)the proportion of alpine meadows in alpine grasslands increased from 50%to 69%,well-reflecting the warming and wetting trend;(2)dominances of Kobresia pygmaea and Stipa purpurea formations in alpine meadows and steppes were strengthened to 76%and 92%,respectively;(3)the climate factor mainly drove the distribution of Stipa purpurea formation,but not the recent distribution of Kobresia pygmaea formation that was likely shaped by human activities.Therefore,the underlying mechanisms of grassland changes over the past 40 years were considered to be formation dependent.Overall,the first exploration for structural information of plant community changes in this study not only provides a new perspective to understand drivers of grassland changes and their spatial heterogeneity at the regional scale of the Tibetan Plateau,but also innovates large-scale vegetation study paradigm.展开更多
Adaptations of ciliates to hypoxic environments have arisen independently several times.Studies on mitochondrion-related organelle(MRO)metabolisms from distinct anaerobic ciliate groups provide evidence for understand...Adaptations of ciliates to hypoxic environments have arisen independently several times.Studies on mitochondrion-related organelle(MRO)metabolisms from distinct anaerobic ciliate groups provide evidence for understanding the transitions from mitochondria to MROs within eukaryotes.To deepen our knowledge about the evolutionary patterns of ciliate anaerobiosis,mass-culture and single-cell transcriptomes of two anaerobic species,Metopus laminarius(class Armophorea)and Plagiopyla cf.narasimhamurtii(class Plagiopylea),were sequenced and their MRO metabolic maps were compared.In addition,we carried out comparisons using publicly available predicted MRO proteomes from other ciliate classes(i.e.,Armophorea,Litostomatea,Muranotrichea,Oligohymenophorea,Parablepharismea and Plagiopylea).We found that single-cell transcriptomes were similarly comparable to their mass-culture counterparts in predicting MRO metabolic pathways of ciliates.The patterns of the components of the MRO metabolic pathways might be divergent among anaerobic ciliates,even among closely related species.Notably,our findings indicate the existence of group-specific functional relics of electron transport chains(ETCs).Detailed group-specific ETC functional patterns are as follows:full oxidative phosphorylation in Oligohymenophorea and Muranotrichea;only electron-transfer machinery in Armophorea;either of these functional types in Parablepharismea;and ETC functional absence in Litostomatea and Plagiopylea.These findings suggest that adaptation of ciliates to anaerobic conditions is group-specific and has occurred multiple times.Our results also show the potential and the limitations of detecting ciliate MRO proteins using single-cell transcriptomes and improve the understanding of the multiple transitions from mitochondria to MROs within ciliates.展开更多
基金supported by the National Natural Science Foundation of China(51767012)Curriculum Ideological and Political Connotation Construction Project of Kunming University of Science and Technology(2021KS009)Kunming University of Science and Technology Online Open Course(MOOC)Construction Project(202107).
文摘This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary structure.This approach capitalizes on the boundary’s capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the line.During internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring lines.Conversely,for faults external to the line,the energy is lower compared to adjacent lines.EWT is employed to decompose the collected fault current signals,allowing access to the high-frequency transient energy.The longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the boundary.Moreover,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances.
基金This research was funded by grants from Pan-Third Pole Environment Study for a Green Silk Road(Pan-TPE),Strategic Priority Research Program of Chinese Academy of Sciences(XDA20050204).
文摘The difficulty of effectively monitoring and managing the environment to conserve biodiversity is as yet an unsolved conundrum.A project of the Chinese Academy of Sciences has concluded that progress can be made through the use of flagship species selected using criteria drawn from conservation biology,ecosystem function,socio-economics,and cultural importance.Inclusion of the latter three criteria will help attract and maintain the commitment of the public to play full parts in carrying out any conservation measures needed.A system is proposed for scoring species to select those that are most suitable as flagships.This method can be used regardless of the size of the area chosen for attention,whether it is a region,a country,or a particular protected area.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0304-02)Joint Chinese Academy of Sciences(CAS)-Max Planck Society(MPG)Research Project(HZXM20225001MI)+3 种基金the Strategic Priority Research Program A of Chinese Academy of Sciences(XDA20050104)the National Natural Science Foundation of China(42041005)CAS Light of West China Programthe Fundamental Research Funds for the Central Universities。
文摘Structural information of grassland changes on the Tibetan Plateau is essential for understanding alterations in critical ecosystem functioning and their underlying drivers that may reflect environmental changes.However,such information at the regional scale is still lacking due to methodological limitations.Beyond remote sensing indicators only recognizing vegetation productivity,we utilized multivariate data fusion and deep learning to characterize formation-based plant community structure in alpine grasslands at the regional scale of the Tibetan Plateau for the first time and compared it with the earlier version of Vegetation Map of China for historical changes.Over the past 40 years,we revealed that(1)the proportion of alpine meadows in alpine grasslands increased from 50%to 69%,well-reflecting the warming and wetting trend;(2)dominances of Kobresia pygmaea and Stipa purpurea formations in alpine meadows and steppes were strengthened to 76%and 92%,respectively;(3)the climate factor mainly drove the distribution of Stipa purpurea formation,but not the recent distribution of Kobresia pygmaea formation that was likely shaped by human activities.Therefore,the underlying mechanisms of grassland changes over the past 40 years were considered to be formation dependent.Overall,the first exploration for structural information of plant community changes in this study not only provides a new perspective to understand drivers of grassland changes and their spatial heterogeneity at the regional scale of the Tibetan Plateau,but also innovates large-scale vegetation study paradigm.
基金supported by the National Natural Science Foundation of China(Grant Number 32070406)Guangdong Basic and Applied Basic Research Foundation(Grant Number 2022A1515010773)the Science and Technology Planning Project of Guangzhou(Grant Number 202102080168).
文摘Adaptations of ciliates to hypoxic environments have arisen independently several times.Studies on mitochondrion-related organelle(MRO)metabolisms from distinct anaerobic ciliate groups provide evidence for understanding the transitions from mitochondria to MROs within eukaryotes.To deepen our knowledge about the evolutionary patterns of ciliate anaerobiosis,mass-culture and single-cell transcriptomes of two anaerobic species,Metopus laminarius(class Armophorea)and Plagiopyla cf.narasimhamurtii(class Plagiopylea),were sequenced and their MRO metabolic maps were compared.In addition,we carried out comparisons using publicly available predicted MRO proteomes from other ciliate classes(i.e.,Armophorea,Litostomatea,Muranotrichea,Oligohymenophorea,Parablepharismea and Plagiopylea).We found that single-cell transcriptomes were similarly comparable to their mass-culture counterparts in predicting MRO metabolic pathways of ciliates.The patterns of the components of the MRO metabolic pathways might be divergent among anaerobic ciliates,even among closely related species.Notably,our findings indicate the existence of group-specific functional relics of electron transport chains(ETCs).Detailed group-specific ETC functional patterns are as follows:full oxidative phosphorylation in Oligohymenophorea and Muranotrichea;only electron-transfer machinery in Armophorea;either of these functional types in Parablepharismea;and ETC functional absence in Litostomatea and Plagiopylea.These findings suggest that adaptation of ciliates to anaerobic conditions is group-specific and has occurred multiple times.Our results also show the potential and the limitations of detecting ciliate MRO proteins using single-cell transcriptomes and improve the understanding of the multiple transitions from mitochondria to MROs within ciliates.
