Triple-negative breast cancer(TNBC)is characterized by fast growth,high metastasis,high invasion,and a lack of therapeutic targets.Mitosis and metastasis of TNBC cells are two important biological behaviors in TNBC ma...Triple-negative breast cancer(TNBC)is characterized by fast growth,high metastasis,high invasion,and a lack of therapeutic targets.Mitosis and metastasis of TNBC cells are two important biological behaviors in TNBC malignant progression.It is well known that the long noncoding RNA AFAP1-AS1 plays a crucial role in various tumors,but whether AFAP1-AS1 is involved in the mitosis of TNBC cells remains unknown.In this study,we investigated the functional mechanism of AFAP1-AS1 in targeting Polo-like Kinase 1(PLK1)activation and participating in mitosis of TNBC cells.We detected the expression of AFAP1-AS1 in the TNBC patient cohort and primary cells by in situ hybridization(ISH),northern blot,fluorescent in situ hybridization(FISH)and cell nucleus/cytoplasm RNA fraction isolation.High AFAP1-AS1 expression was negatively correlated with overall survival(OS),disease-free survival(DFS),metastasis-free survival(MFS)and recurrence-free survival(RFS)in TNBC patients.We explored the function of AFAP1-AS1 by transwell,apoptosis,immunofluorescence(IF)and patient-derived xenograft(PDX)models in vitro and in vivo.We found that AFAP1-AS1 promoted TNBC primary cell survival by inhibiting mitotic catastrophe and increased TNBC primary cell growth,migration and invasion.Mechanistically,AFAP1-AS1 activated phosphorylation of the mitosis-associated kinase PLK1 protein.Elevated levels of AFAP1-AS1 in TNBC primary cells increased PLK1 pathway downstream gene expression,such as CDC25C,CDK1,BUB1 and TTK.More importantly,AFAP1-AS1 increased lung metastases in a mouse metastasis model.Taken together,AFAP1-AS1 functions as an oncogene that activates the PLK1 signaling pathway.AFAP1-AS1 could be used as a potential prognostic marker and therapeutic target for TNBC.展开更多
To give play to the role of agricultural catastrophe risk fund in spreading agricultural catastrophe risk,we select natural conditions,economic conditions,social conditions,as the external vulnerability assessment ind...To give play to the role of agricultural catastrophe risk fund in spreading agricultural catastrophe risk,we select natural conditions,economic conditions,social conditions,as the external vulnerability assessment indicators;select commodity rate of agricultural products,substitutability of agricultural products,the extent of agricultural products being related to the national economy and the people's livelihood,as the internal vulnerability assessment indicators.We assign weight to indicators using Analytic Hierarchy Process,and establish assessment indicator system of agricultural catastrophe vulnerability,to analyze the compensation for losses of different agricultural products arising from agricultural catastrophe in different regions.And we take the case of rice in Sichuan Province,to demonstrate the role this indicator system.展开更多
A sudden increase of vibration amplitude with no foreboding often results in an abrupt breakdown of a mechanical system.The catastrophe of vibration state of a faulty rotor is a typical nonlinear phenomenon,and very d...A sudden increase of vibration amplitude with no foreboding often results in an abrupt breakdown of a mechanical system.The catastrophe of vibration state of a faulty rotor is a typical nonlinear phenomenon,and very difficult to be described and predicted with linear vibration theory.On the basis of nonlinear vibration and catastrophe theory,fhe eatastrophe of the vibration amplitude of the faulty rotor is described;a way to predict its emergence is developed.展开更多
This paper presents an attempt at the application of catastrophe theory to the stabilityanalysis of J-controlled crack growth in three-point bending specimens. By introducing the solutions ofJ-integral in the complete...This paper presents an attempt at the application of catastrophe theory to the stabilityanalysis of J-controlled crack growth in three-point bending specimens. By introducing the solutions ofJ-integral in the completely yielding state for the ideal plastic material, the critical condition of losingstability for the crack propagation in the specimen is obtained, based on the cusp catastrophe theory.The process of the crack growth from geometrical sense is described.展开更多
A model of butterfly catastrophe is confirmed based on the matching and fitting the previousexperimental data from alumina electrolysis when anode effect occurs.The complicatedbehaviour of the cryolite-alumina melt sy...A model of butterfly catastrophe is confirmed based on the matching and fitting the previousexperimental data from alumina electrolysis when anode effect occurs.The complicatedbehaviour of the cryolite-alumina melt system with varying parameters could be generallydescribed by this model.Therefore,the anode effect and its occurrence may be thoroughlyunderstood.展开更多
Catastrophe theory was used to investigate the fracture behavior of thin_wall cylindrical tubes subjected to internal explosive pressure. Based on the energy theory and catastrophe theory, a cusp catastrophe model for...Catastrophe theory was used to investigate the fracture behavior of thin_wall cylindrical tubes subjected to internal explosive pressure. Based on the energy theory and catastrophe theory, a cusp catastrophe model for the fracture was established, and a critical condition associated with the model is given.展开更多
It is in references[4,5]that the combination of the relative researches of pansystems methodology and the researches of bifurcation,catastrophe,chaos and stability in nonlinear mechanics was put forward and the concep...It is in references[4,5]that the combination of the relative researches of pansystems methodology and the researches of bifurcation,catastrophe,chaos and stability in nonlinear mechanics was put forward and the concepts were redefined from the point of view of pansystems methodology.The present paper studies the logic conservation law of these nonlinear mechanics phenomena under the framework of pansystems methodology.展开更多
The stability of ore pillar in mine is essential for the safe and efficient mining.Based on the energy evolvement rule in ore pillar and roadway roof system,the roadway roof and ore pillar are treated as energy releas...The stability of ore pillar in mine is essential for the safe and efficient mining.Based on the energy evolvement rule in ore pillar and roadway roof system,the roadway roof and ore pillar are treated as energy release body and energy dissipation body,respectively.Therefore,the double-block mechanical model is established with energy dissipation body and energy release body,and the energy mechanism of ore pillar instability is obtained,based on the fold catastrophe mathematical theory.The research result indicates that the dynamic instability of ore pillar is a physical instability problem caused by the strain softening property of ore mass,and the instability type of ore pillar is determined by the stiffness parameter of double-block mechanical system.When the systematical stiffness parameter is greater than or equal to 1,the equilibrium position of double-block mechanical system passes through shaft K-1 or the origin,from branch 1 of unstable equilibrium state to branch 2 of stable equilibrium state by smooth transition,and the ore pillar shows quasi-static fracture.When the systematical stiffness parameter is less than 1,the equilibrium position of double-block system mutates from branch 1 of unstable equilibrium state to branch 2 of stable equilibrium state by jumping transition,and the ore pillar shows dynamic instability.The research result could provide theoretical guidance for the prevention measures of ore pillar instability.展开更多
The study on transition states is one of the most important pathways to understand the essence of chemical reactions. With the development of femtoseeond pulse technique, Zewail et al. have carried out a number of exp...The study on transition states is one of the most important pathways to understand the essence of chemical reactions. With the development of femtoseeond pulse technique, Zewail et al. have carried out a number of experimental studies on the transition states, while the theoretical chemists has a great interest in the topic. In the展开更多
The relationship between work and energy increment of a thrust fault system with quasi-static deformation can be decomposed into two parts: volume strain energy and deviation stress energy. The relationship between wo...The relationship between work and energy increment of a thrust fault system with quasi-static deformation can be decomposed into two parts: volume strain energy and deviation stress energy. The relationship between work and energy increment of the deviation stress of a simplified thrust fault system is analyzed based on the catastrophe theory. The research indicates that the characteristics displayed by the fold catastrophe model can appropriately describe the condition of earthquake generation, the evolvement process of main shock of thrust fault earthquake, and some important aftershock properties. The bigger the surrounding press of surrounding rock is, the bigger the maximum principal stress is, the smaller the incidences of the potential thrust fault surface are, and the smaller the ratio between the tangential stiffness of surrounding rock and the slope is, which is at the inflexion point on the softened zone of the fault shearing strength curve. Thus, when earthquake occurrs, the larger the elastic energy releasing amount of surrounding rock is, the bigger the earthquake magnitude is, the larger the half distance of fault dislocation is, and the larger the displacement amplitude of end face of surrounding rock is. Fracturing and expanding the fault rock body and releasing the volume strain energy of surrounding rock during the earthquake can enhance the foregoing effects together.展开更多
Data acquired in the area of Environmental Sciences are by their very nature often discontinuous and abrupt. As such, the mathematical theories of catastrophe and chaos may be of use in analyzing such scientific data ...Data acquired in the area of Environmental Sciences are by their very nature often discontinuous and abrupt. As such, the mathematical theories of catastrophe and chaos may be of use in analyzing such scientific data and in formulating mathematical models.展开更多
Drought generally has significant impacts on crops.It is essential to quantitatively evaluate the relationship between crop production and drought degree to provide technical support for drought disaster prevention.In...Drought generally has significant impacts on crops.It is essential to quantitatively evaluate the relationship between crop production and drought degree to provide technical support for drought disaster prevention.In this study,a drought degree index that can reflect the changes in precipitation,evapotranspiration,and soil moisture was developed on the basis of crop yield reduction rate.Four drought scenarios were set up to simulate the effects of meteorological drought on drought degree of crops at different growth stages.A cusp catastrophe model was constructed to analyze the mutation characteristics of the drought degree of maize at different growth stages under different meteorological drought conditions.Xi'an City in China was selected as the study area,and summer maize was selected as the research crop.Precipitation and crop yield data from 1951 to 2010 were used as the fundamental data to investigate drought degree mutation of summer maize.The results show that,under the meteorological drought conditions at the emergence-jointing stage,drought degree may change abruptly,and soil moisture content at the sowingemergence,jointing-tasseling,and tasseling-mature stages should be kept higher than 39%.展开更多
In this study, based on the analysis of the catastrophic risk of rural drinking water, with the representative villages in Ya’an as study objects and setting the four evaluation standards: water quality, water quanti...In this study, based on the analysis of the catastrophic risk of rural drinking water, with the representative villages in Ya’an as study objects and setting the four evaluation standards: water quality, water quantity, the Guarantee Probability for water Supply and the Convenience Level of the Access to Water Supply as the ba- sic framework, a Rural Drinking Water Safety Assessment was developed (RDWSA). Research showed that Catastrophe Theory was applicable in the RDWSA. Adding RDWSA based on Catastrophe Theory to the supportive system for decision-making in Ecological Hydrographic Management Decision Support System of Ya’an helped obtain the rank and results of RDWSE by the automatic calculation of programs, which could assist the risk assessment and risk management associated with rural drinking water in Ya’an.展开更多
"The Belt and Road Initiative"is major decision proposed by the CPC Central Committee with comrade Xi Jinping as the core co-ordinating the domestic and international overall situations,and concerns peaceful..."The Belt and Road Initiative"is major decision proposed by the CPC Central Committee with comrade Xi Jinping as the core co-ordinating the domestic and international overall situations,and concerns peaceful rise of China and extension of the strategic opportunity period of modernization construction.It needs multi-faceted safeguards to successfully impel"the Belt and Road Initiative",in which disaster risk identification and its effective prevention and control are indispensable links.By integrating geogeographic and atmospheric environmental factors,countries along"the Belt and Road Initiative"belong to frequent occurrence region of major natural disasters.It restricts not only the economic and social development of relevant countries but also implementation effect of"the Belt and Road Initiative"construction,and is also related to the success or failure of Chinese enterprises going out to a certain extent.It should enhance disaster prevention and mitigation and ensure safety of major infrastructure construction related to interconnection of"the Belt and Road Initiative"by disaster identification and prevention,which is the key of successfully impelling strategy implementation and major need for guaranteeing the people s livelihood of the countries along the line.The work of disaster prevention and mitigation in the countries along the line is generally weak,and it is urgent to raise the level of disaster prevention as a whole by promoting the disaster prevention and mitigation cooperation in the"the Belt and Road Initiative"area;improve the coverage and level of disaster risk insurance;enhance construction in monitoring and early warning capability of natural disaster;strengthen structural adjustment of economy,industry and land use responding to climate change risks;establish a comprehensive disaster reduction forum of"the Belt and Road Initiative",and contain relevant content in"the Belt and Road Initiative"series of high-end forum topics.展开更多
This paper introduces agricultural catastrophe and its characteristics,and conducts comparative analysis on existing mechanism of spreading agricultural catastrophe risk,indicating that the mechanism of administrative...This paper introduces agricultural catastrophe and its characteristics,and conducts comparative analysis on existing mechanism of spreading agricultural catastrophe risk,indicating that the mechanism of administrative remedy has the greatest efficiency and highest cost;the mechanism of social assistance has the lowest cost,but its efficiency is lowest and there are unstable factors;market mechanism,namely the insurance of agricultural catastrophe,is the rational choice of agricultural department in mechanism of risk spreading.This paper analyzes the status quo of China's insurance of agricultural catastrophe,indicating that the main body of management in China's insurance of agricultural catastrophe is missing.In addition,the market demand is critically scanty,and insurance of agricultural catastrophe lacks external development environment.The gap of China's insurance law of agricultural catastrophe has become the greatest obstacle to the development of insurance of agricultural catastrophe.From legislative purpose,basic principle,nature,main body of legal relations,management range,policy support,supervision and management and so on,the legislation conception of China's insurance of agricultural catastrophe is put forward.展开更多
Half of a century has passed on Fisher’ambiguity pictures(1967).To celebrate this occasion,we have analysed his data,using the polynomial function for a cusp catastrophe,and we have discussed the results under dynami...Half of a century has passed on Fisher’ambiguity pictures(1967).To celebrate this occasion,we have analysed his data,using the polynomial function for a cusp catastrophe,and we have discussed the results under dynamical systems theory’propositions.展开更多
基金supported by the Natural Science Foundation of China(Nos.82002782,82202657)the Guangdong Basic and Applied Basic Research Foundation(2022A1515012021,2020A1515110930).
文摘Triple-negative breast cancer(TNBC)is characterized by fast growth,high metastasis,high invasion,and a lack of therapeutic targets.Mitosis and metastasis of TNBC cells are two important biological behaviors in TNBC malignant progression.It is well known that the long noncoding RNA AFAP1-AS1 plays a crucial role in various tumors,but whether AFAP1-AS1 is involved in the mitosis of TNBC cells remains unknown.In this study,we investigated the functional mechanism of AFAP1-AS1 in targeting Polo-like Kinase 1(PLK1)activation and participating in mitosis of TNBC cells.We detected the expression of AFAP1-AS1 in the TNBC patient cohort and primary cells by in situ hybridization(ISH),northern blot,fluorescent in situ hybridization(FISH)and cell nucleus/cytoplasm RNA fraction isolation.High AFAP1-AS1 expression was negatively correlated with overall survival(OS),disease-free survival(DFS),metastasis-free survival(MFS)and recurrence-free survival(RFS)in TNBC patients.We explored the function of AFAP1-AS1 by transwell,apoptosis,immunofluorescence(IF)and patient-derived xenograft(PDX)models in vitro and in vivo.We found that AFAP1-AS1 promoted TNBC primary cell survival by inhibiting mitotic catastrophe and increased TNBC primary cell growth,migration and invasion.Mechanistically,AFAP1-AS1 activated phosphorylation of the mitosis-associated kinase PLK1 protein.Elevated levels of AFAP1-AS1 in TNBC primary cells increased PLK1 pathway downstream gene expression,such as CDC25C,CDK1,BUB1 and TTK.More importantly,AFAP1-AS1 increased lung metastases in a mouse metastasis model.Taken together,AFAP1-AS1 functions as an oncogene that activates the PLK1 signaling pathway.AFAP1-AS1 could be used as a potential prognostic marker and therapeutic target for TNBC.
文摘To give play to the role of agricultural catastrophe risk fund in spreading agricultural catastrophe risk,we select natural conditions,economic conditions,social conditions,as the external vulnerability assessment indicators;select commodity rate of agricultural products,substitutability of agricultural products,the extent of agricultural products being related to the national economy and the people's livelihood,as the internal vulnerability assessment indicators.We assign weight to indicators using Analytic Hierarchy Process,and establish assessment indicator system of agricultural catastrophe vulnerability,to analyze the compensation for losses of different agricultural products arising from agricultural catastrophe in different regions.And we take the case of rice in Sichuan Province,to demonstrate the role this indicator system.
文摘A sudden increase of vibration amplitude with no foreboding often results in an abrupt breakdown of a mechanical system.The catastrophe of vibration state of a faulty rotor is a typical nonlinear phenomenon,and very difficult to be described and predicted with linear vibration theory.On the basis of nonlinear vibration and catastrophe theory,fhe eatastrophe of the vibration amplitude of the faulty rotor is described;a way to predict its emergence is developed.
文摘This paper presents an attempt at the application of catastrophe theory to the stabilityanalysis of J-controlled crack growth in three-point bending specimens. By introducing the solutions ofJ-integral in the completely yielding state for the ideal plastic material, the critical condition of losingstability for the crack propagation in the specimen is obtained, based on the cusp catastrophe theory.The process of the crack growth from geometrical sense is described.
文摘A model of butterfly catastrophe is confirmed based on the matching and fitting the previousexperimental data from alumina electrolysis when anode effect occurs.The complicatedbehaviour of the cryolite-alumina melt system with varying parameters could be generallydescribed by this model.Therefore,the anode effect and its occurrence may be thoroughlyunderstood.
文摘Catastrophe theory was used to investigate the fracture behavior of thin_wall cylindrical tubes subjected to internal explosive pressure. Based on the energy theory and catastrophe theory, a cusp catastrophe model for the fracture was established, and a critical condition associated with the model is given.
文摘It is in references[4,5]that the combination of the relative researches of pansystems methodology and the researches of bifurcation,catastrophe,chaos and stability in nonlinear mechanics was put forward and the concepts were redefined from the point of view of pansystems methodology.The present paper studies the logic conservation law of these nonlinear mechanics phenomena under the framework of pansystems methodology.
基金This work was supported by the National Natural Science Foundation of China(51704095,51774110,51504081)the Research Fund of the State Key Laboratory of Coal Resources and Safe Mining(13KF02)+2 种基金the Research Fund of Henan Key Laboratory for Green and Efficient Mining and Comprehensive Utilization of Mineral Resources(S201619)the Foundation for Higher Education Key Research Project by Henan Province(18A440012,14A440001)the Ph.D.Programs Foundation of Henan Polytechnic University(B2014-50,B2016-67).
文摘The stability of ore pillar in mine is essential for the safe and efficient mining.Based on the energy evolvement rule in ore pillar and roadway roof system,the roadway roof and ore pillar are treated as energy release body and energy dissipation body,respectively.Therefore,the double-block mechanical model is established with energy dissipation body and energy release body,and the energy mechanism of ore pillar instability is obtained,based on the fold catastrophe mathematical theory.The research result indicates that the dynamic instability of ore pillar is a physical instability problem caused by the strain softening property of ore mass,and the instability type of ore pillar is determined by the stiffness parameter of double-block mechanical system.When the systematical stiffness parameter is greater than or equal to 1,the equilibrium position of double-block mechanical system passes through shaft K-1 or the origin,from branch 1 of unstable equilibrium state to branch 2 of stable equilibrium state by smooth transition,and the ore pillar shows quasi-static fracture.When the systematical stiffness parameter is less than 1,the equilibrium position of double-block system mutates from branch 1 of unstable equilibrium state to branch 2 of stable equilibrium state by jumping transition,and the ore pillar shows dynamic instability.The research result could provide theoretical guidance for the prevention measures of ore pillar instability.
基金Supported by the National Natural Science Foundation of China
文摘The study on transition states is one of the most important pathways to understand the essence of chemical reactions. With the development of femtoseeond pulse technique, Zewail et al. have carried out a number of experimental studies on the transition states, while the theoretical chemists has a great interest in the topic. In the
基金supported by the National Natural Science Foundation of China (No. 5067059)
文摘The relationship between work and energy increment of a thrust fault system with quasi-static deformation can be decomposed into two parts: volume strain energy and deviation stress energy. The relationship between work and energy increment of the deviation stress of a simplified thrust fault system is analyzed based on the catastrophe theory. The research indicates that the characteristics displayed by the fold catastrophe model can appropriately describe the condition of earthquake generation, the evolvement process of main shock of thrust fault earthquake, and some important aftershock properties. The bigger the surrounding press of surrounding rock is, the bigger the maximum principal stress is, the smaller the incidences of the potential thrust fault surface are, and the smaller the ratio between the tangential stiffness of surrounding rock and the slope is, which is at the inflexion point on the softened zone of the fault shearing strength curve. Thus, when earthquake occurrs, the larger the elastic energy releasing amount of surrounding rock is, the bigger the earthquake magnitude is, the larger the half distance of fault dislocation is, and the larger the displacement amplitude of end face of surrounding rock is. Fracturing and expanding the fault rock body and releasing the volume strain energy of surrounding rock during the earthquake can enhance the foregoing effects together.
文摘Data acquired in the area of Environmental Sciences are by their very nature often discontinuous and abrupt. As such, the mathematical theories of catastrophe and chaos may be of use in analyzing such scientific data and in formulating mathematical models.
基金This work was supported by the Key Scientific and Technological Research Project in Henan Province(Grant No.192102110199).
文摘Drought generally has significant impacts on crops.It is essential to quantitatively evaluate the relationship between crop production and drought degree to provide technical support for drought disaster prevention.In this study,a drought degree index that can reflect the changes in precipitation,evapotranspiration,and soil moisture was developed on the basis of crop yield reduction rate.Four drought scenarios were set up to simulate the effects of meteorological drought on drought degree of crops at different growth stages.A cusp catastrophe model was constructed to analyze the mutation characteristics of the drought degree of maize at different growth stages under different meteorological drought conditions.Xi'an City in China was selected as the study area,and summer maize was selected as the research crop.Precipitation and crop yield data from 1951 to 2010 were used as the fundamental data to investigate drought degree mutation of summer maize.The results show that,under the meteorological drought conditions at the emergence-jointing stage,drought degree may change abruptly,and soil moisture content at the sowingemergence,jointing-tasseling,and tasseling-mature stages should be kept higher than 39%.
文摘In this study, based on the analysis of the catastrophic risk of rural drinking water, with the representative villages in Ya’an as study objects and setting the four evaluation standards: water quality, water quantity, the Guarantee Probability for water Supply and the Convenience Level of the Access to Water Supply as the ba- sic framework, a Rural Drinking Water Safety Assessment was developed (RDWSA). Research showed that Catastrophe Theory was applicable in the RDWSA. Adding RDWSA based on Catastrophe Theory to the supportive system for decision-making in Ecological Hydrographic Management Decision Support System of Ya’an helped obtain the rank and results of RDWSE by the automatic calculation of programs, which could assist the risk assessment and risk management associated with rural drinking water in Ya’an.
基金Supported by China Postdoctoral Science Foundation(2019T120114,2019M650756)the National Natural Science Fund(41801064)the Central Asian Atmospheric Science Research Fund(CAAS201804)
文摘"The Belt and Road Initiative"is major decision proposed by the CPC Central Committee with comrade Xi Jinping as the core co-ordinating the domestic and international overall situations,and concerns peaceful rise of China and extension of the strategic opportunity period of modernization construction.It needs multi-faceted safeguards to successfully impel"the Belt and Road Initiative",in which disaster risk identification and its effective prevention and control are indispensable links.By integrating geogeographic and atmospheric environmental factors,countries along"the Belt and Road Initiative"belong to frequent occurrence region of major natural disasters.It restricts not only the economic and social development of relevant countries but also implementation effect of"the Belt and Road Initiative"construction,and is also related to the success or failure of Chinese enterprises going out to a certain extent.It should enhance disaster prevention and mitigation and ensure safety of major infrastructure construction related to interconnection of"the Belt and Road Initiative"by disaster identification and prevention,which is the key of successfully impelling strategy implementation and major need for guaranteeing the people s livelihood of the countries along the line.The work of disaster prevention and mitigation in the countries along the line is generally weak,and it is urgent to raise the level of disaster prevention as a whole by promoting the disaster prevention and mitigation cooperation in the"the Belt and Road Initiative"area;improve the coverage and level of disaster risk insurance;enhance construction in monitoring and early warning capability of natural disaster;strengthen structural adjustment of economy,industry and land use responding to climate change risks;establish a comprehensive disaster reduction forum of"the Belt and Road Initiative",and contain relevant content in"the Belt and Road Initiative"series of high-end forum topics.
文摘This paper introduces agricultural catastrophe and its characteristics,and conducts comparative analysis on existing mechanism of spreading agricultural catastrophe risk,indicating that the mechanism of administrative remedy has the greatest efficiency and highest cost;the mechanism of social assistance has the lowest cost,but its efficiency is lowest and there are unstable factors;market mechanism,namely the insurance of agricultural catastrophe,is the rational choice of agricultural department in mechanism of risk spreading.This paper analyzes the status quo of China's insurance of agricultural catastrophe,indicating that the main body of management in China's insurance of agricultural catastrophe is missing.In addition,the market demand is critically scanty,and insurance of agricultural catastrophe lacks external development environment.The gap of China's insurance law of agricultural catastrophe has become the greatest obstacle to the development of insurance of agricultural catastrophe.From legislative purpose,basic principle,nature,main body of legal relations,management range,policy support,supervision and management and so on,the legislation conception of China's insurance of agricultural catastrophe is put forward.
文摘Half of a century has passed on Fisher’ambiguity pictures(1967).To celebrate this occasion,we have analysed his data,using the polynomial function for a cusp catastrophe,and we have discussed the results under dynamical systems theory’propositions.
