Wheat powdery mildew （Pro） is a major disease of wheat worldwide. During the past years, numerous studies have been published on molecular mapping of Pm resistance gene（s） in wheat. We summarized the relevant find...Wheat powdery mildew （Pro） is a major disease of wheat worldwide. During the past years, numerous studies have been published on molecular mapping of Pm resistance gene（s） in wheat. We summarized the relevant findings of 89 major re- sistance gene mapping studies and 25 quantitative trait loci （QTL） mapping studies. Major Pm resistance genes and QTLs were found on all wheat chromosomes, but the Pm resistance genes/QTLs were not randomly distributed on each chromosome of wheat. The summarized data showed that the A or B genome has more major Pm resistance genes than the D genome and chromosomes 1A, 2A, 2B, 5B, 5D, 6B, 7A and 7B harbor more major Pm resistance genes than the other chromosomes. For adult plant resistance （APR） genes/QTLs, B genome of wheat harbors more APR genes than A and D genomes, and chromo- somes 2A, 4A, 5A, 1B, 2B, 3B, 5B, 6B, 7B, 2D, 5D and 7D harbor more Pm resistance QTLs than the other chromosomes, suggesting that A genome except 1A, 3A and 6A, B genome except 4B, D genome except 1D, 3D, 4D, and 6D play an impor- tant role in wheat combating against powdery mildew. Furthermore, Pm resistance genes are derived from wheat and its rela- tives, which suggested that the resistance sources are diverse and Pm resistance genes are diverse and useful in combating against the powdery mildew isolates. In this review, four APR genes, Pm38/Lr34/Yr18/Sr57, Pm46/Lr67/Yr46/Sr55, Pm？/Lr27/Yr30/ SY2 and Pm39/Lr46/Yr29, are not only resistant to powdery mildew but also effective for rust diseases in the field, indicating that such genes are stable and useful in wheat breeding programmes. The summarized data also provide chromosome locations or linked markers for Pm resistance genes/QTLs. Markers linked to these genes can also be utilized to pyramid diverse Pm resis- tance genes/QTLs more efficiently by marker-assisted selection.展开更多
It is a new field to arouse the motive force of poverty alleviation and improve the poverty alleviation performance research by actively mobilizing enterprises to participate in poverty alleviation and development. In...It is a new field to arouse the motive force of poverty alleviation and improve the poverty alleviation performance research by actively mobilizing enterprises to participate in poverty alleviation and development. In the context of mass entrepreneurship and innovation,the innovation research has already formed the perfect union with the theories related to management science and the economics,but its combination with the sociology,especially with the enterprise-led poverty alleviation research is also very scarce. Under the premise of affirming the mode of enterprise participation in poverty alleviation,this paper explores and analyzes the practical value of this model in three aspects: innovating poverty alleviation model,enhancing the poor people's self-restoration ability,weakening the dual structure of urban and rural areas. This paper clarifies the internal relations among the subjects under the model. This paper also puts forward the innovation direction of poverty alleviation by enterprises in the future in big data focusing,innovative thinking embedding,model innovation,information feedback of the main body,which provides a theoretical basis and direction guidance for the follow-up related research.展开更多
Let be a given Hermitian matrix satisfying . Using the eigenvalue decomposition of , we consider the least squares solutions to the matrix equation , with the constraint .
A square complex matrix is called if it can be written in the form with being fixed unitary and being arbitrary matrix in . We give necessary and sufficient conditions for the existence of the solution to the system o...A square complex matrix is called if it can be written in the form with being fixed unitary and being arbitrary matrix in . We give necessary and sufficient conditions for the existence of the solution to the system of complex matrix equation and present an expression of the solution to the system when the solvability conditions are satisfied. In addition, the solution to an optimal approximation problem is obtained. Furthermore, the least square solution with least norm to this system mentioned above is considered. The representation of such solution is also derived.展开更多
Antiferroelectric materials with double hysteresis loops are attractive for energy storage applications,which are becoming increasingly important for power electronics nowadays.Among them,AgNbO_(3) based lead-free cer...Antiferroelectric materials with double hysteresis loops are attractive for energy storage applications,which are becoming increasingly important for power electronics nowadays.Among them,AgNbO_(3) based lead-free ceramics have attracted intensive interest as one of promising environmental-friendly candidates.However,most of the AgNbO_(3) based ceramics suffers from low dielectric breakdown strength(Eb).The limitation of low Eb is broken to some extent in this work.Here,AgNbO_(3) epitaxial films were fabricated by pulsed laser deposition,which possess high Eb of 624 kV/cm.The(001)AgNbO_(3) epitaxial film reveals typical antiferroelectric hysteresis loops when the applied electric fields are over 300 kV/cm.A recoverable energy density of 5.8 J/cm^(3) and an energy efficiency of 55.8%are obtained at 600 kV/cm,which demonstrates the great promise of the AgNbO_(3) film for energy storage applications.展开更多
Aims Extreme climate events have become more severe and frequent with global change in recent years.The Chinese temperate steppes are an important component of the Eurasian steppes and highly sensitive and vulnerable ...Aims Extreme climate events have become more severe and frequent with global change in recent years.The Chinese temperate steppes are an important component of the Eurasian steppes and highly sensitive and vulnerable to climatic change.As a result,the occur-rence of extreme climate events must have strong impacts on the temperate steppes.Therefore,understanding the spatio-temporal trends in extreme climate is important for us to assess the sensitivity and vulnerability of Chinese temperate steppes to climatic changes.This research had two specific objects to(i)specify the temporal changes in extreme climate events across the whole steppe and(ii)compare the trend differences for extreme climate events in differ-ent types of steppes-meadow steppe,typical steppe and desert steppe.Methods To investigate extreme climate trends in the temperate steppes of China,82 meteorological stations with daily temperature and precipi-tation data(1961-2013)were used.Meanwhile,eight core extreme climate indices(extreme high-temperature threshold,extreme low-temperature threshold,frost days,heatwave duration,heavy rain-fall threshold,percentage of heavy rainfall,heavy rainfall days and consecutive dry days)from the Statistical and Regional Dynamical Downscaling of Extremes for European Regions(STARDEX)project were selected to analyse the trends in extreme climate across the whole temperate steppe and the three main types(meadow steppe,typical steppe and desert steppe)through time and space.Important Findings The results showed that(i)the changes in extreme climatic tem-perature events across the whole temperate steppe were obvi-ous during 1961-2013.The frost days(−3.40 days/10 year[yr])decreased significantly,while the extreme high-temperature thresh-old(0.24℃/10 yr),extreme low-temperature threshold(0.52℃/10 yr),and heatwave duration(0.58 days/10 yr)increased notably.The annual changes in extreme precipitation were small and not sig-nificant.(ii)Differences appeared in the extreme climatic trends in different types of steppes.The desert steppe showed strong climate extremes and underwent the most significant asymmetric warming compared with the meadow steppe and typical steppe.At the same time,the heatwave duration(0.62 days/10 yr)increased.In terms of the extreme precipitation,there was no significant trend among the three types of steppes.However,the fluctuations in extreme precipi-tation were the largest in the desert steppe compared to those in the typical steppe and meadow steppe.展开更多
Transparent conductive films(TCFs)are crucial components of solar cells.In this study,F,Cl,and Ga codoped ZnO(FCGZO)TCFs were deposited onto a glass substrate using the sol-gel spin-coating method and rapid thermal an...Transparent conductive films(TCFs)are crucial components of solar cells.In this study,F,Cl,and Ga codoped ZnO(FCGZO)TCFs were deposited onto a glass substrate using the sol-gel spin-coating method and rapid thermal annealing.The effects of F-doping content on the structural,morphological,electrical,and optical properties of FCGZO films were examined by XRD,TEM,FE-SEM,PL spectroscopy,XPS,Hall effects testing,and UVeviseNIR spectroscopy.All prepared ZnO films exhibited a hexagonal wurtzite structure and preferentially grew along the c axis perpendicular to the substrate.Changes in the doping concentration of F changed the interplanar crystal spacing and O vacancies in the film.At a doping ratio of 2%(in mole),the F,Cl,and Ga co-doped ZnO film exhibited the best photoelectric performance,with a carrier concentration of 2.62×10^(20)cm^(-3),mobility of 14.56 cm^(2)/(V·s),and resistivity of 1.64×10^(-3)Ucm.The average transmittance(AT)in the 380-1600 nm region nearly 90%with air as the reference,and the optical band gap was 3.52 eV.展开更多
基金Supported by the NSF of China(Grant no.31471488)State Key Laboratory of Crop Biology(2017KF03)+3 种基金Shandong Province Key Technology Innovation Project(2014GJJS0201-1)Transgenic Special Item(2016ZX08002003)National Modern Agricultural Industry System Construction Project(CARS-03-1-8)The Scholars of Taishan Seed Industry Project(2014-2019)
文摘Wheat powdery mildew （Pro） is a major disease of wheat worldwide. During the past years, numerous studies have been published on molecular mapping of Pm resistance gene（s） in wheat. We summarized the relevant findings of 89 major re- sistance gene mapping studies and 25 quantitative trait loci （QTL） mapping studies. Major Pm resistance genes and QTLs were found on all wheat chromosomes, but the Pm resistance genes/QTLs were not randomly distributed on each chromosome of wheat. The summarized data showed that the A or B genome has more major Pm resistance genes than the D genome and chromosomes 1A, 2A, 2B, 5B, 5D, 6B, 7A and 7B harbor more major Pm resistance genes than the other chromosomes. For adult plant resistance （APR） genes/QTLs, B genome of wheat harbors more APR genes than A and D genomes, and chromo- somes 2A, 4A, 5A, 1B, 2B, 3B, 5B, 6B, 7B, 2D, 5D and 7D harbor more Pm resistance QTLs than the other chromosomes, suggesting that A genome except 1A, 3A and 6A, B genome except 4B, D genome except 1D, 3D, 4D, and 6D play an impor- tant role in wheat combating against powdery mildew. Furthermore, Pm resistance genes are derived from wheat and its rela- tives, which suggested that the resistance sources are diverse and Pm resistance genes are diverse and useful in combating against the powdery mildew isolates. In this review, four APR genes, Pm38/Lr34/Yr18/Sr57, Pm46/Lr67/Yr46/Sr55, Pm？/Lr27/Yr30/ SY2 and Pm39/Lr46/Yr29, are not only resistant to powdery mildew but also effective for rust diseases in the field, indicating that such genes are stable and useful in wheat breeding programmes. The summarized data also provide chromosome locations or linked markers for Pm resistance genes/QTLs. Markers linked to these genes can also be utilized to pyramid diverse Pm resis- tance genes/QTLs more efficiently by marker-assisted selection.
基金Supported by Student Program Funded by Special Research Funds for Central Universities
文摘It is a new field to arouse the motive force of poverty alleviation and improve the poverty alleviation performance research by actively mobilizing enterprises to participate in poverty alleviation and development. In the context of mass entrepreneurship and innovation,the innovation research has already formed the perfect union with the theories related to management science and the economics,but its combination with the sociology,especially with the enterprise-led poverty alleviation research is also very scarce. Under the premise of affirming the mode of enterprise participation in poverty alleviation,this paper explores and analyzes the practical value of this model in three aspects: innovating poverty alleviation model,enhancing the poor people's self-restoration ability,weakening the dual structure of urban and rural areas. This paper clarifies the internal relations among the subjects under the model. This paper also puts forward the innovation direction of poverty alleviation by enterprises in the future in big data focusing,innovative thinking embedding,model innovation,information feedback of the main body,which provides a theoretical basis and direction guidance for the follow-up related research.
文摘Let be a given Hermitian matrix satisfying . Using the eigenvalue decomposition of , we consider the least squares solutions to the matrix equation , with the constraint .
文摘A square complex matrix is called if it can be written in the form with being fixed unitary and being arbitrary matrix in . We give necessary and sufficient conditions for the existence of the solution to the system of complex matrix equation and present an expression of the solution to the system when the solvability conditions are satisfied. In addition, the solution to an optimal approximation problem is obtained. Furthermore, the least square solution with least norm to this system mentioned above is considered. The representation of such solution is also derived.
基金supported by the National Natural Science Foundation of China(No.51802068 and No.52073144)Advanced Talents Incubation Program of the Hebei University,China(No.801260201180)+2 种基金the Natural Science Foundation of Jiangsu Province,China(No.BK20201301)the State Key Laboratory of New Ceramic and Fine Processing Tsinghua University(No.KF202005)the Basic Scientific Research Program of National Institute of Metrology(No.AKY1949).
文摘Antiferroelectric materials with double hysteresis loops are attractive for energy storage applications,which are becoming increasingly important for power electronics nowadays.Among them,AgNbO_(3) based lead-free ceramics have attracted intensive interest as one of promising environmental-friendly candidates.However,most of the AgNbO_(3) based ceramics suffers from low dielectric breakdown strength(Eb).The limitation of low Eb is broken to some extent in this work.Here,AgNbO_(3) epitaxial films were fabricated by pulsed laser deposition,which possess high Eb of 624 kV/cm.The(001)AgNbO_(3) epitaxial film reveals typical antiferroelectric hysteresis loops when the applied electric fields are over 300 kV/cm.A recoverable energy density of 5.8 J/cm^(3) and an energy efficiency of 55.8%are obtained at 600 kV/cm,which demonstrates the great promise of the AgNbO_(3) film for energy storage applications.
基金National Natural Science Foundation of China(41775108)Agriculture to Climate Change(132020010406)Industry of National Public Welfare(Meteorological)Scientific Research(GYHY201406034).Conflict of interest.None declared.
文摘Aims Extreme climate events have become more severe and frequent with global change in recent years.The Chinese temperate steppes are an important component of the Eurasian steppes and highly sensitive and vulnerable to climatic change.As a result,the occur-rence of extreme climate events must have strong impacts on the temperate steppes.Therefore,understanding the spatio-temporal trends in extreme climate is important for us to assess the sensitivity and vulnerability of Chinese temperate steppes to climatic changes.This research had two specific objects to(i)specify the temporal changes in extreme climate events across the whole steppe and(ii)compare the trend differences for extreme climate events in differ-ent types of steppes-meadow steppe,typical steppe and desert steppe.Methods To investigate extreme climate trends in the temperate steppes of China,82 meteorological stations with daily temperature and precipi-tation data(1961-2013)were used.Meanwhile,eight core extreme climate indices(extreme high-temperature threshold,extreme low-temperature threshold,frost days,heatwave duration,heavy rain-fall threshold,percentage of heavy rainfall,heavy rainfall days and consecutive dry days)from the Statistical and Regional Dynamical Downscaling of Extremes for European Regions(STARDEX)project were selected to analyse the trends in extreme climate across the whole temperate steppe and the three main types(meadow steppe,typical steppe and desert steppe)through time and space.Important Findings The results showed that(i)the changes in extreme climatic tem-perature events across the whole temperate steppe were obvi-ous during 1961-2013.The frost days(−3.40 days/10 year[yr])decreased significantly,while the extreme high-temperature thresh-old(0.24℃/10 yr),extreme low-temperature threshold(0.52℃/10 yr),and heatwave duration(0.58 days/10 yr)increased notably.The annual changes in extreme precipitation were small and not sig-nificant.(ii)Differences appeared in the extreme climatic trends in different types of steppes.The desert steppe showed strong climate extremes and underwent the most significant asymmetric warming compared with the meadow steppe and typical steppe.At the same time,the heatwave duration(0.62 days/10 yr)increased.In terms of the extreme precipitation,there was no significant trend among the three types of steppes.However,the fluctuations in extreme precipi-tation were the largest in the desert steppe compared to those in the typical steppe and meadow steppe.
基金the Key Research and Development Projects of Hebei Province(Grant No.19214301D)the Key Project of Science and Technology Research in Higher Education Institutions of Hebei Province(Grant No.ZD2022024)+3 种基金the Natural Science Foundation of Hebei Province(Grant Nos A2019405059,A2022405002)the Starting Fund for Independent Doctoral Research of Hebei Agricultural University(PY2021005)the General Projects of Hebei North University(Grant No.XJ2021001)the Innovation and Entrepreneurship Training Program for College Students of Hebei North University(Grant Nos 202210092007,S202210092006).
文摘Transparent conductive films(TCFs)are crucial components of solar cells.In this study,F,Cl,and Ga codoped ZnO(FCGZO)TCFs were deposited onto a glass substrate using the sol-gel spin-coating method and rapid thermal annealing.The effects of F-doping content on the structural,morphological,electrical,and optical properties of FCGZO films were examined by XRD,TEM,FE-SEM,PL spectroscopy,XPS,Hall effects testing,and UVeviseNIR spectroscopy.All prepared ZnO films exhibited a hexagonal wurtzite structure and preferentially grew along the c axis perpendicular to the substrate.Changes in the doping concentration of F changed the interplanar crystal spacing and O vacancies in the film.At a doping ratio of 2%(in mole),the F,Cl,and Ga co-doped ZnO film exhibited the best photoelectric performance,with a carrier concentration of 2.62×10^(20)cm^(-3),mobility of 14.56 cm^(2)/(V·s),and resistivity of 1.64×10^(-3)Ucm.The average transmittance(AT)in the 380-1600 nm region nearly 90%with air as the reference,and the optical band gap was 3.52 eV.
