Tianfu No.1 is bred from a plant in the population of Sichuan through system selection,which is characterized with early and uniform germination,hypertrophic shoots,full cover with pekoes and long picking period of si...Tianfu No.1 is bred from a plant in the population of Sichuan through system selection,which is characterized with early and uniform germination,hypertrophic shoots,full cover with pekoes and long picking period of single shoots.Compared with those of Fuding white tea(CK),the fresh leaf yield,tea polyphenols content,free amino acids content,caffeine content and soluble sugar content of Tianfu No.1 were increased by 8.89%,6.98%,10.00%,2.96%and31.58%,respectively.Tianfu No.1 is a new rare breakthrough tea variety with high development potential,good intrinsic biochemical quality,and strong adaptability for processing multi-typed tea products such as green tea,white tea,black tea and dark tea,etc.It has strong stress resistance and can still grow better in low-humidity areas.In addition,it is not easy to flower and fruit.展开更多
Based on field research data of farmers in Zhejiang Province, the authors analyzed factors influencing farmers' participation in forest farmers cooperatives (hereafter referred to as FFCs) by the binary logistic r...Based on field research data of farmers in Zhejiang Province, the authors analyzed factors influencing farmers' participation in forest farmers cooperatives (hereafter referred to as FFCs) by the binary logistic regression model. Results show that understanding of farmers about cooperatives has a great influence on their behavior of participation in FFCs. Besides, educational level of householders and existing member scale of cooperatives also have significant influence on farmers' behavior of participation in cooperatives. Therefore, it is required to strengthen propaganda of cooperatives, deepen their understanding of cooperatives; cultivate new high quality farmers to provide talents for development of cooperatives; establish incentive mechanism to encourage farmers to participate in cooperatives.展开更多
DNA is the carrier of genetic information, and its sequence can be designed to realize many important functions, including DNAzyme, aptamer and even structurally precise nanomaterials. The development of DNA nanotechn...DNA is the carrier of genetic information, and its sequence can be designed to realize many important functions, including DNAzyme, aptamer and even structurally precise nanomaterials. The development of DNA nanotechnol- ogy combined functional nucleic acids with nanomaterials for various effective biomedical applications. Here, we reviewed the application of DNA-nanomaterials in two biomedical fields： early diagnosis and drug delivery. And in each field, we mainly focused on two kinds of nanomaterials： metallic nanoparticles and DNA self-assembled na- nomaterials. DNA metallic nanomaterials showed unique optical, electronic and magnetic properties in bioanalysis, and when functioned by DNA, their specificity was improved for both biosensor development and drug delivery. More recently, many DNA self-assembled nanomaterials were introduced into biomedical application for their well-defined structure and excellent biocompatibility. We summarized the research of these two kinds of DNA- nanomaterials for biomedical purposes, and finally made some prospection about their future development.展开更多
Heterocyclic aramid fibers,a typical kind of high-performance fibers,have been widely used in aerospace and protection fields because of their excellent mechanical properties.However,the application of heterocyclic ar...Heterocyclic aramid fibers,a typical kind of high-performance fibers,have been widely used in aerospace and protection fields because of their excellent mechanical properties.However,the application of heterocyclic aramid fibers as a reinforcement is hindered by the weak interfacial combination with matrix materials,especially epoxy.Traditional strategies enhancing the interfacial shear strength(IFSS)usually decrease the tensile strength.Therefore,simultaneous enhancement of both mechanical properties remains a challenge.Herein,we report a novel heterocyclic aramid fiber with high interfacial shear strength(49.3 MPa)and tensile strength(6.27 GPa),in which 4,4′-diamino-2′-chlorobenzanilide(DABA-Cl)and a small amount of graphene oxide(GO)are introduced through in-situ polymerization.Hydrogen bonds andπ–πinteraction between GO and polymer chains trigger the enhancement in crystallinity,orientation,and lateral interaction of the fibers,thus improving the tensile strength and interfacial shear strength of the fibers.Moreover,the interfacial interaction between fiber and epoxy is enhanced due to the improvement of the surface polarity of the fibers caused by DABA-Cl.Therefore,a method to improve both tensile strength and interfacial shear strength of heterocyclic aramid fibers was found by introducing GO and DABA-Cl,which may provide guidance for the design and preparation of other high-performance fibers.展开更多
Ratiometric DNA biosensors,which utilize DNA as the recognition element and integrate dual signals from diverse sensing platforms including fluorescence,electrochemistry,and surface-enhanced Raman scattering(SERS),hav...Ratiometric DNA biosensors,which utilize DNA as the recognition element and integrate dual signals from diverse sensing platforms including fluorescence,electrochemistry,and surface-enhanced Raman scattering(SERS),have demonstrated remarkable proficiency in detecting a wide range of targets.In this review,we showcase the significant progress achieved by ratiometric biosensors.Firstly,ratiometric biosensors have made notable advancements in analyzing real samples.These include the analysis of pH values near cancer cells,quantification of miRNA in human cell lysates,detection of human telomerase RNA in cell extracts,and performing DNA logicgated in situ bioimaging on cell membranes.Secondly,excellent sensitivity has been attained through the utilization of effective amplification methods such as RCA,HCR,and CHA,among others.Thirdly,the construction of stable reference signals has resulted in significantly improved precision for ratiometric biosensors.This breakthrough has overcome matrix effects,enabling reliable detection in real samples with high selectivity.This review provides a comprehensive overview of recent advancements in strategies employed by ratiometric DNA biosensors.We present three types of biosensors based on distinct sensing platforms:fluorescent,electrochemical,and SERS biosensors.Additionally,we discuss future directions and primary challenges in the development of ratiometric DNA biosensors.展开更多
基金Supported by Sichuan Financial Public-Welfare Deepened Engineering Research Project(2016GYSH-019)Earmarked Fund for China Agriculture Research System(CARS-19)
文摘Tianfu No.1 is bred from a plant in the population of Sichuan through system selection,which is characterized with early and uniform germination,hypertrophic shoots,full cover with pekoes and long picking period of single shoots.Compared with those of Fuding white tea(CK),the fresh leaf yield,tea polyphenols content,free amino acids content,caffeine content and soluble sugar content of Tianfu No.1 were increased by 8.89%,6.98%,10.00%,2.96%and31.58%,respectively.Tianfu No.1 is a new rare breakthrough tea variety with high development potential,good intrinsic biochemical quality,and strong adaptability for processing multi-typed tea products such as green tea,white tea,black tea and dark tea,etc.It has strong stress resistance and can still grow better in low-humidity areas.In addition,it is not easy to flower and fruit.
基金Supported by the Project of Food and Agricultural Organization of the United Nations(GCP/CPR/038/200906)the Project of Zhejiang Province Forestry Department(07A13)
文摘Based on field research data of farmers in Zhejiang Province, the authors analyzed factors influencing farmers' participation in forest farmers cooperatives (hereafter referred to as FFCs) by the binary logistic regression model. Results show that understanding of farmers about cooperatives has a great influence on their behavior of participation in FFCs. Besides, educational level of householders and existing member scale of cooperatives also have significant influence on farmers' behavior of participation in cooperatives. Therefore, it is required to strengthen propaganda of cooperatives, deepen their understanding of cooperatives; cultivate new high quality farmers to provide talents for development of cooperatives; establish incentive mechanism to encourage farmers to participate in cooperatives.
文摘DNA is the carrier of genetic information, and its sequence can be designed to realize many important functions, including DNAzyme, aptamer and even structurally precise nanomaterials. The development of DNA nanotechnol- ogy combined functional nucleic acids with nanomaterials for various effective biomedical applications. Here, we reviewed the application of DNA-nanomaterials in two biomedical fields： early diagnosis and drug delivery. And in each field, we mainly focused on two kinds of nanomaterials： metallic nanoparticles and DNA self-assembled na- nomaterials. DNA metallic nanomaterials showed unique optical, electronic and magnetic properties in bioanalysis, and when functioned by DNA, their specificity was improved for both biosensor development and drug delivery. More recently, many DNA self-assembled nanomaterials were introduced into biomedical application for their well-defined structure and excellent biocompatibility. We summarized the research of these two kinds of DNA- nanomaterials for biomedical purposes, and finally made some prospection about their future development.
基金the Ministry of Science and Technology of China(No.2016YFA0200100)the Beijing National Laboratory for Molecular Sciences(No.BNLMS-CXTD-202001)+1 种基金the National Natural Science Foundation of China(Nos.52102035,52021006,T2188101,51720105003,and 21790052)the Strategic Priority Research Program of CAS(No.XDB36030100).
文摘Heterocyclic aramid fibers,a typical kind of high-performance fibers,have been widely used in aerospace and protection fields because of their excellent mechanical properties.However,the application of heterocyclic aramid fibers as a reinforcement is hindered by the weak interfacial combination with matrix materials,especially epoxy.Traditional strategies enhancing the interfacial shear strength(IFSS)usually decrease the tensile strength.Therefore,simultaneous enhancement of both mechanical properties remains a challenge.Herein,we report a novel heterocyclic aramid fiber with high interfacial shear strength(49.3 MPa)and tensile strength(6.27 GPa),in which 4,4′-diamino-2′-chlorobenzanilide(DABA-Cl)and a small amount of graphene oxide(GO)are introduced through in-situ polymerization.Hydrogen bonds andπ–πinteraction between GO and polymer chains trigger the enhancement in crystallinity,orientation,and lateral interaction of the fibers,thus improving the tensile strength and interfacial shear strength of the fibers.Moreover,the interfacial interaction between fiber and epoxy is enhanced due to the improvement of the surface polarity of the fibers caused by DABA-Cl.Therefore,a method to improve both tensile strength and interfacial shear strength of heterocyclic aramid fibers was found by introducing GO and DABA-Cl,which may provide guidance for the design and preparation of other high-performance fibers.
基金financially supported by:The National Quality Infrastructure Program of China(2021YFF0600705 NQI)the Natural Science Foundation of China(No.22074093).
文摘Ratiometric DNA biosensors,which utilize DNA as the recognition element and integrate dual signals from diverse sensing platforms including fluorescence,electrochemistry,and surface-enhanced Raman scattering(SERS),have demonstrated remarkable proficiency in detecting a wide range of targets.In this review,we showcase the significant progress achieved by ratiometric biosensors.Firstly,ratiometric biosensors have made notable advancements in analyzing real samples.These include the analysis of pH values near cancer cells,quantification of miRNA in human cell lysates,detection of human telomerase RNA in cell extracts,and performing DNA logicgated in situ bioimaging on cell membranes.Secondly,excellent sensitivity has been attained through the utilization of effective amplification methods such as RCA,HCR,and CHA,among others.Thirdly,the construction of stable reference signals has resulted in significantly improved precision for ratiometric biosensors.This breakthrough has overcome matrix effects,enabling reliable detection in real samples with high selectivity.This review provides a comprehensive overview of recent advancements in strategies employed by ratiometric DNA biosensors.We present three types of biosensors based on distinct sensing platforms:fluorescent,electrochemical,and SERS biosensors.Additionally,we discuss future directions and primary challenges in the development of ratiometric DNA biosensors.
