The generation of high-repetition rate(frep≥10 GHz)ultra-broadband optical frequency combs(OFCs)at 1550 nm and 1310 nm is investigated by seeding two types of highly nonlinear fibers(HNLFs)with 10 GHz picosecond puls...The generation of high-repetition rate(frep≥10 GHz)ultra-broadband optical frequency combs(OFCs)at 1550 nm and 1310 nm is investigated by seeding two types of highly nonlinear fibers(HNLFs)with 10 GHz picosecond pulses at the pump wavelength of 1550 nm.When pumped near the zero dispersion wavelength(ZDW)in the normal dispersion region of a HNLF,10 GHz flat-topped OFC with 43 nm bandwidth within 5 dB power variation is generated by self-phase modulation(SPM)-based OFC spectral broadening at 26.5 dBm pump power,and 291 fs pulse trains with 10 GHz repetition rate are obtained at 18 dBm pump power without complicated pulse shaping methods.Furthermore,when pumped in the abnormal dispersion region of a HNLF,OFCs with dispersive waves around 1310 nm are studied using a common HNLF and fluorotellurite fibers,which maintain the good coherence of the pump light at 1550 nm.At the same time,sufficient tunability of the generated dispersive waves is achieved when tuning the pump power or ZDW.展开更多
Agricultural colleges and universities shoulder the arduous task of cultivating talents for rural revitalization,in which ideological and political education is the key link in talent training.Ideological and politica...Agricultural colleges and universities shoulder the arduous task of cultivating talents for rural revitalization,in which ideological and political education is the key link in talent training.Ideological and political education helps cultivate reliable talents for rural revitalization,stimulate the endogenous power of rural revitalization,and realize direct and indirect promotion of rural revitalization.However,there are still many issues in ideological and political education in terms of educational concept,educational content,and educational model.Hence,it is necessary to strengthen the role of ideological and political education in promoting rural revitalization by clarifying the goals and concepts of ideological and political education in agricultural colleges and universities,strengthening the cultivation of students’awareness of rural revitalization services,and innovating ideological and political education models.展开更多
A major goal of poplar breeding is to obtain new insect-resistant poplar varieties through genetic engineering.However,engineering poplars with only a single insect-resistant gene has limitations,such as narrow insect...A major goal of poplar breeding is to obtain new insect-resistant poplar varieties through genetic engineering.However,engineering poplars with only a single insect-resistant gene has limitations,such as narrow insecticidal bands and the rapid development of insect tolerance to the gene.To expand insecticidal bands,delay the development of insect tolerance,and improve the insect resistance of transgenic poplars,polygene polymerization is increasingly being applied to cultivate insect-resistant poplars.In the present study,we discuss polygene polymerization,applications of the polygene combination strategy,the current state of research on transgenic poplar with multiple insect-resistant genes,including existing problems,and future research directions.We provide reference data to aid the cultivation and utilization of new polygenic insect-resistant poplar varieties.展开更多
Ferulic acid inclusion complexes(FA-HP-β-CD)effects on tyramine accumulation and gene expression of Enterobacter hormaechei MW386398 in traditional smoked horsemeat sausages were studied.Reverse transcription-quantit...Ferulic acid inclusion complexes(FA-HP-β-CD)effects on tyramine accumulation and gene expression of Enterobacter hormaechei MW386398 in traditional smoked horsemeat sausages were studied.Reverse transcription-quantitative polymerase chain reaction(RT-qPCR)was used to identify the expression of tyrosine decarboxylase(TDC)clusters in the tyramine producing pathway.In addition,relevant parameters such as microbial growth,moisture content,pH,and tyramine accumulation in pure cultures and during fermentation of smoked horsemeat sausages were evaluated.Ferulic acid(FA)and FA-HP-β-CD inclusion complexes both significantly decreased tyramine accumulation,as well as significantly inhibited tyrosine decarboxylase(tdcA)and tyrosine/tyramine antiporter(tyrP)genes expression(p<0.05).Furthermore,FA and FA-HP-β-CD inclusion complexes both reduced the number of Enterobacteriaceae in smoked horsemeat sausages,but did not alter the main microbiota.However,FA-HP-β-CD inclusion complexes exhibited stronger ability in hindering TDC related gene expression,reducing tyramine accumulation and antibacterial properties.These results indicate that FA-HP-β-CD inclusion complexes are able to reduce tyramine accumulation in smoked horsemeat sausages by inhibiting Enterobacteriaceae growth and gene expression.展开更多
基金We are grateful for financial supports from the National Natural Science Foundation of China(Grant No.61527823)the National Key R&D Program of China(Grant No.2017YFB0405301).
文摘The generation of high-repetition rate(frep≥10 GHz)ultra-broadband optical frequency combs(OFCs)at 1550 nm and 1310 nm is investigated by seeding two types of highly nonlinear fibers(HNLFs)with 10 GHz picosecond pulses at the pump wavelength of 1550 nm.When pumped near the zero dispersion wavelength(ZDW)in the normal dispersion region of a HNLF,10 GHz flat-topped OFC with 43 nm bandwidth within 5 dB power variation is generated by self-phase modulation(SPM)-based OFC spectral broadening at 26.5 dBm pump power,and 291 fs pulse trains with 10 GHz repetition rate are obtained at 18 dBm pump power without complicated pulse shaping methods.Furthermore,when pumped in the abnormal dispersion region of a HNLF,OFCs with dispersive waves around 1310 nm are studied using a common HNLF and fluorotellurite fibers,which maintain the good coherence of the pump light at 1550 nm.At the same time,sufficient tunability of the generated dispersive waves is achieved when tuning the pump power or ZDW.
基金Sichuan Provincial College Ideological and Political Theory Course Teacher Training Center(Grant Number:SZQ2021-2-026)2022 Teaching Reform Research Project by Sichuan University of Science&Engineering(Grant Number:JG-2241)。
文摘Agricultural colleges and universities shoulder the arduous task of cultivating talents for rural revitalization,in which ideological and political education is the key link in talent training.Ideological and political education helps cultivate reliable talents for rural revitalization,stimulate the endogenous power of rural revitalization,and realize direct and indirect promotion of rural revitalization.However,there are still many issues in ideological and political education in terms of educational concept,educational content,and educational model.Hence,it is necessary to strengthen the role of ideological and political education in promoting rural revitalization by clarifying the goals and concepts of ideological and political education in agricultural colleges and universities,strengthening the cultivation of students’awareness of rural revitalization services,and innovating ideological and political education models.
基金supported by the National Key R&D Program of China during the 14th Five-year Plan Period(2021YFD2200102)the Science and technology research project of Higher education in Hebei Province(QN2018022)the Talents Special Fund of Hebei Agricultural University(YJ2021028)。
文摘A major goal of poplar breeding is to obtain new insect-resistant poplar varieties through genetic engineering.However,engineering poplars with only a single insect-resistant gene has limitations,such as narrow insecticidal bands and the rapid development of insect tolerance to the gene.To expand insecticidal bands,delay the development of insect tolerance,and improve the insect resistance of transgenic poplars,polygene polymerization is increasingly being applied to cultivate insect-resistant poplars.In the present study,we discuss polygene polymerization,applications of the polygene combination strategy,the current state of research on transgenic poplar with multiple insect-resistant genes,including existing problems,and future research directions.We provide reference data to aid the cultivation and utilization of new polygenic insect-resistant poplar varieties.
基金This work was supported by grants from the National Natural Science Foundation of China(No.32060547)the key science and technology research projects of Xinjiang production and construction team(No.2020AB012).
文摘Ferulic acid inclusion complexes(FA-HP-β-CD)effects on tyramine accumulation and gene expression of Enterobacter hormaechei MW386398 in traditional smoked horsemeat sausages were studied.Reverse transcription-quantitative polymerase chain reaction(RT-qPCR)was used to identify the expression of tyrosine decarboxylase(TDC)clusters in the tyramine producing pathway.In addition,relevant parameters such as microbial growth,moisture content,pH,and tyramine accumulation in pure cultures and during fermentation of smoked horsemeat sausages were evaluated.Ferulic acid(FA)and FA-HP-β-CD inclusion complexes both significantly decreased tyramine accumulation,as well as significantly inhibited tyrosine decarboxylase(tdcA)and tyrosine/tyramine antiporter(tyrP)genes expression(p<0.05).Furthermore,FA and FA-HP-β-CD inclusion complexes both reduced the number of Enterobacteriaceae in smoked horsemeat sausages,but did not alter the main microbiota.However,FA-HP-β-CD inclusion complexes exhibited stronger ability in hindering TDC related gene expression,reducing tyramine accumulation and antibacterial properties.These results indicate that FA-HP-β-CD inclusion complexes are able to reduce tyramine accumulation in smoked horsemeat sausages by inhibiting Enterobacteriaceae growth and gene expression.
