Fiber cladding surface plasmon resonance(SPR)sensors have few structures,and a clad SPR sensor based on S-type fiber is proposed in this paper.This new type of fiber cladding SPR sensor was formed by electrofusing an ...Fiber cladding surface plasmon resonance(SPR)sensors have few structures,and a clad SPR sensor based on S-type fiber is proposed in this paper.This new type of fiber cladding SPR sensor was formed by electrofusing an S-shaped structure on the fiber to couple the light in the fiber core to the cladding.In this paper,the effects of fiber parameters on the performance of the sensor were studied by simulation and experiment.Based on the conclusion that the smaller the core diameter is,the closer the working band of the SPR resonance is to long wavelengths,and that the geometric characteristics mean that a multimode fiber can receive the fiber cladding light from a small core diameter few-mode fiber,a dual channel SPR sensor with a double S-type fiber cascade was proposed.In the refractive index detection range of 1.333–1.385refractive index units(RIU),the resonant working band of channel I is 627.66 nm–759.78 nm,with an average sensitivity of 2540.77 nm/RIU,and the resonant working band of channel II is 518.24 nm–658.2 nm,with an average sensitivity of2691.54 nm/RIU.The processing method for the S-type fiber cladding SPR sensor is simple,effectively solving the problem of this type of SPR sensor structure and the difficult realization of a dual channel.The sensor is expected to be used in the fields of medical treatment and biological analysis.展开更多
Crack initiation stress and crack damage stress are two critical indices for assessing the fracture strength of rock mass.However,understanding the stress characteristics of crack initiation and damage under triaxial ...Crack initiation stress and crack damage stress are two critical indices for assessing the fracture strength of rock mass.However,understanding the stress characteristics of crack initiation and damage under triaxial compression remains still immature.To address this problem,by acoustic monitoring,i.e.ultrasonic wave transmission and acoustic emission(AE),the integrated triaxial compression experiments were carried out on granitic specimens.The crack initiation and damage stresses were determined by wave velocity,wave amplitude and AE methods,respectively.The discrepancy of stresses for crack initiation and damage identified by these methods were examined.Results showed that the confinement affected the peak stress and corresponding strain,and these two parameters increased with increasing confining pressure.The ultrasonic wave velocity and wave amplitude first increased and then remained relatively stable,and finally decreased with increasing axial compressive stress.The number of AE events stayed at a relatively low extent until axial stress approached the peak;after that,the AE accumulative counts skyrocketed to the maximum.It also shows that for a given confinement,the stresses for crack initiation and damage identified by the wave amplitude method were the smallest,followed those by AE method and wave velocity method.Moreover,the stresses for crack initiation and crack damage identified by these methods increased generally with confining pressures.However,the rate of increment of these two crack stresses decreased with increasing confining pressure.In addition,the slight decrease in these two crack stresses ratios was noticed with increasing confining pressure.The findings are helpful to understand the crack stresses of deep rocks,in terms of support of deep underground engineering.展开更多
Power transmission across the sea is an important part of global energy interconnection(GEI).To support the construction of GEI and to serve the needs of future clean energy trans-sea transportation and offshore wind ...Power transmission across the sea is an important part of global energy interconnection(GEI).To support the construction of GEI and to serve the needs of future clean energy trans-sea transportation and offshore wind power development,this study a)analyzes the requirements of the GEI backbone network pertaining to direct current(DC)submarine cable technology,and b)defines the key technical and economic indices of ultrahigh-voltage direct current(UHVDC)submarine cable based on theoretical computations.The research is based on the thermoelectric coupling model and the finite element method.It is shown that the dielectric strength of the insulating materials of the±800 kV~±1100 kV/4000 MW^12000 MW UHVDC submarine cable(extrusion insulation)should be not less than 43~65 kV/mm,while the heat resistance is not less than 110°C.As the cost of submarine cable is 5~10 times higher than that of the overhead line,the project investment need to be decreased to a level within the economical carrying capacity to guarantee extensive applicability of the HVDC submarine cable technology.展开更多
The demands for massive renewable energy integration, passive network power supply, and global energy interconnection have all gradually increased, posing new challenges for high voltage direct current(HVDC) power tra...The demands for massive renewable energy integration, passive network power supply, and global energy interconnection have all gradually increased, posing new challenges for high voltage direct current(HVDC) power transmission systems, including more complex topology and increased diversity of bipolar HVDC transmission. This study proposes that these two factors have led to new requirements for HVDC control strategies. Moreover, due to the diverse applications of HVDC transmission technology, each station in the system has different requirements. Furthermore, the topology of the AC-DC converter is being continuously developed, revealing a trend towards hybrid converter stations.展开更多
OBJECTIVE To investigate the potential malignant characteristics and pathogenesis of endometriosis as well as the role of human growth hormone and epidermal growth factor receptor in the pathogenesis of malignant tran...OBJECTIVE To investigate the potential malignant characteristics and pathogenesis of endometriosis as well as the role of human growth hormone and epidermal growth factor receptor in the pathogenesis of malignant transformation of endometriosis. METHODS The immunohistochemical S-P method was used to examine the expression of human growth hormone and epidermal growth factor receptor in the eutopic and ectopic endometrium of 84 cases of endometriosis. RESULTS The percentage of positive cases of human growth hormone in eutopic and ectopic endometrium was 90.77% （59/65） and 85.71% （72/ 84） respectively. The percentage of positive cases of epidermal growth factor receptor in eutopic and ectopic endometrium was 81.54% （53/65） and 89.29% （75/84） respectively. The positive rate of epidermal growth factor receptor in ectopic endometrium was higher than that in the eutopic endometrium but without a statistically significant difference （P〉 0.05）. CONCLUSION Endometriosis is caused by multiple factors, which possesses some biologic features of neoplastic tissue such as invasion and metastasis. Both human growth hormone and epidermal growth factor receptor are highly expressed in eutopic and ectopic endometrium, which lead directly or indirectly to the pathogenesis of endometriosis and promote the initiation and malignant transformation of endometriosis.展开更多
In order to control the working wavelength range of the fiber surface plasmon resonance(SPR)temperature sensor and realize the wavelength division multiplexing type multi-channel fiber SPR temperature sensor,by compre...In order to control the working wavelength range of the fiber surface plasmon resonance(SPR)temperature sensor and realize the wavelength division multiplexing type multi-channel fiber SPR temperature sensor,by comprehensively investigating the influence of liquids with different thermal-optical coefficients and solid packaging materials on the performance of fiber SPR temperature sensor,a dual-channel fiber SPR temperature sensor based on liquid-solid cascade encapsulation was designed and fabricated.The liquid temperature sensing stage encapsulated in capillary worked in 616.03 nm-639.05 nm band,the solid sensing stage coated with pouring sealant worked in 719.37 nm-825.27 nm band,and the two stages were cascaded to form a fiber dual-channel temperature sensor.The testing results indicated that when the temperature range was 35℃-95℃,the sensitivity of two-stage temperature detection was−0.384 nm/℃and−1.765 nm/℃respectively.The proposed fiber sensor has simple fabrication and excellent performance which can be widely used in various fields of dual-channel temperature measurement and temperature compensation.展开更多
A fiber cladding surface plasmon resonance(SPR)bending sensor is realized by the cladding of the fiber structure.By employing coating film,the sensing zone is protected and the toughness of the sensor increases.Three ...A fiber cladding surface plasmon resonance(SPR)bending sensor is realized by the cladding of the fiber structure.By employing coating film,the sensing zone is protected and the toughness of the sensor increases.Three different sensing probes are tested,the experiment results indicate that the two parameters(wavelength sensitivity and light intensity sensitivity)sensing performances of the eccentric butt joint structures are superior to that of hetero-core structure,and the SPR bending sensor based on hetero-core structure is stable and uneasy to damage.By employing hetero-core fiber and silver film,a fiber cladding SPR bending sensor with better stabilization and sensing performance is realized.The proposed fabricating method of sensing probe with coating film provides a new approach for fiber SPR-distributed bending sensor.展开更多
The current interruption capability of a gas, when used in high voltage gas-blast circuit breakers,depends not only on its material properties but also the flow field since turbulence plays a dominant role in arc cool...The current interruption capability of a gas, when used in high voltage gas-blast circuit breakers,depends not only on its material properties but also the flow field since turbulence plays a dominant role in arc cooling during the interruption process. Based on available experimental results, a study of CO2 switching arcs under a DC（direct current） current in the model circuit breaker has been conducted to calibrate CO2 arc model and to analyse its electric and thermal property. Through detailed analysis of the results mechanisms responsible for the temperature distribution are identified and the domain energy transportation process of different region discussed. The present work provides significant coefficients for CO2 switching arc simulation and gives a better understanding of CO2 arc burning mechanisms.展开更多
Sterol regulatory element-binding factor-1 and-2(SREBF1 and SREBF2)are important transcription factors involved in the regulating lipid homeostasis.Based on the essential role of SREBF1 and SREBF2,we measured the mRNA...Sterol regulatory element-binding factor-1 and-2(SREBF1 and SREBF2)are important transcription factors involved in the regulating lipid homeostasis.Based on the essential role of SREBF1 and SREBF2,we measured the mRNA expression levels of the two genes in six various tissues at different growth points.Our results showed that the SREBF1 and SREBF2 were expressed in all six tissues examined in Erlang mountainous chicken(SD02)at 42 d,and were expressed abundantly in the uropygial gland and liver,with relatively lowest levels of expression in the abdominal fat,sebum cutaneum and leg muscle.The expression ratio of SREBF1 and SREBF2 in breast muscle,leg muscle,sebum cutaneum and uropygial gland exhibited a"decline-rise"trend.However,in liver,the expression ratio of these two genes exhibited a"decline-rise-decline"trend.Meanwhile,the expression level of SREBF1 gene of all tissues was lower than that of SREBF2 except for uropygial gland.The findings will provide important references for further function investigation of the two genes involved in fat deposition in chickens.展开更多
[Objectives] The aim was to study the artificial cultivation of Bletilla striata to realize large scale and standardization planting. [Methods] The comparison tests were conducted on B. striata with different canopy d...[Objectives] The aim was to study the artificial cultivation of Bletilla striata to realize large scale and standardization planting. [Methods] The comparison tests were conducted on B. striata with different canopy densities of the Magnolia officinalis forests,different compound planting densities and different tending measures and management. [Results] When the stand canopy density was 0. 4-0. 6,the per unit yield of B. striata was 5. 4%,6. 8% higher than that at the canopy density of less than 0. 4 and more than 0. 6,respectively. When the planting density was 30 cm × 30 cm,the per unit yield increased by 16. 1%,12. 0%,13. 1% respectively compared with the planting density of 20 cm × 20 cm,25 cm × 25 cm,35 cm × 35 cm. When B. striata was planted from October to November,the per unit yield was 5. 6% higher than that planted from December to January of the following year,and 21. 3% higher than that from February to March of the second year. When farmyard manure was applied during the cultivation,the per unit yield was 31. 7% and 18. 4% higher than the application of chemical fertilizer and compound fertilizer. When weeding 4 times per year,the per unit yield increased by 240. 1%,137. 0% and 43. 9% respectively from that weeding 1 times,2 times,3 times per year. [Conclusions]When planting B. striata,the stand canopy density of 0. 4-0. 6 could make it receive absolutely shelters and the lighting conditions required for the growth,thereby bringing in high emergence rate,good growth potential and high yield. The best planting effect of B. striata could achieve by planting from October to November with the planting density of 30 cm × 30 cm,which can play the maximum benefit of individual plants. Moreover,weeding 4 times per year combined with the use of farmyard manure can promote the development and growth of tubers,which can greatly improve the yield of B. striata.展开更多
Introduction:Plague is a zoonotic disease that occurs naturally in specific geographic areas.Climate change can influence the populations of the plague host or vector,leading to variations in the occurrence and epidem...Introduction:Plague is a zoonotic disease that occurs naturally in specific geographic areas.Climate change can influence the populations of the plague host or vector,leading to variations in the occurrence and epidemiology of plague in animals.Methods:In this study,we collected meteorological and plague epidemiological data from the Marmota himalayana plague focus in the Altun Mountains of the Qinghai-Xizang Plateau.The data spanned from 2000 to 2022.We describe the climatic factors and plague epidemic conditions and we describe their analysis by Pearson’s correlation.Results:During the period from 2000 to 2022,the isolation rates of Yersinia pestis(Y.pestis)from marmots and fleas were 9.27%(451/4,864)and 7.17%(118/1,646),respectively.Additionally,we observed a positive rate of F1 antibody of 11.25%(443/3,937)in marmots and 18.16%(142/782)in dogs.With regards to climate,there was little variation,and a decreasing trend in blowing-sand days was observed.The temperature in the previous year showed a negative correlation with the Y.pestis isolation rate in marmots(r=−0.555,P=0.011)and the positive rate of F1 antibody in marmots(r=−0.552,P=0.012)in the current year.The average annual precipitation in the previous two years showed a positive correlation with marmot density(r=0.514,P=0.024),while blowingsand days showed a negative correlation with marmot density(r=−0.701,P=0.001).Furthermore,the average annual precipitation in the previous three years showed a positive correlation with the isolation rate of Y.pestis from marmots(r=0.666,P=0.003),and blowing-sand days showed a negative correlation with marmot density(r=−0.597,P=0.009).Conclusions:The findings of this study indicate that there is a hysteresis effect of climate change on the prevalence of plague.Therefore,monitoring climate conditions can offer significant insights for implementing timely preventive and control measures to combat plague epidemics.展开更多
基金the National Natural Science Foundation of China(Grant No.61705025)Chongqing Natural Science Foundation(Grant Nos.cstc2019jcyjmsxmX0431 and cstc2018jcyjAX0817)+2 种基金the Science and Technology Project Affiliated to the Education Department of Chongqing Municipality(Grant Nos.KJQN201801217,KJQN201901226,KJQN202001214,and KJ1710247)Chongqing Key Laboratory of Geological Environment Monitoring and Disaster Early-Warning in Three Gorges Reservoir Area(Grant Nos.ZD2020A0103 and ZD2020A0102)Fundamental Research Funds for Chongqing Three Gorges University of China(Grant No.19ZDPY08).
文摘Fiber cladding surface plasmon resonance(SPR)sensors have few structures,and a clad SPR sensor based on S-type fiber is proposed in this paper.This new type of fiber cladding SPR sensor was formed by electrofusing an S-shaped structure on the fiber to couple the light in the fiber core to the cladding.In this paper,the effects of fiber parameters on the performance of the sensor were studied by simulation and experiment.Based on the conclusion that the smaller the core diameter is,the closer the working band of the SPR resonance is to long wavelengths,and that the geometric characteristics mean that a multimode fiber can receive the fiber cladding light from a small core diameter few-mode fiber,a dual channel SPR sensor with a double S-type fiber cascade was proposed.In the refractive index detection range of 1.333–1.385refractive index units(RIU),the resonant working band of channel I is 627.66 nm–759.78 nm,with an average sensitivity of 2540.77 nm/RIU,and the resonant working band of channel II is 518.24 nm–658.2 nm,with an average sensitivity of2691.54 nm/RIU.The processing method for the S-type fiber cladding SPR sensor is simple,effectively solving the problem of this type of SPR sensor structure and the difficult realization of a dual channel.The sensor is expected to be used in the fields of medical treatment and biological analysis.
基金funded by Shenzhen Basic Research Program,China(Grant No.JCYJ20220818095605012)the Program for Guangdong Introducing Innovative and Entrepreneurial Teams,China(Grant No.2019ZT08G315)the National Science Foundation of China(Grant No.52121003).
文摘Crack initiation stress and crack damage stress are two critical indices for assessing the fracture strength of rock mass.However,understanding the stress characteristics of crack initiation and damage under triaxial compression remains still immature.To address this problem,by acoustic monitoring,i.e.ultrasonic wave transmission and acoustic emission(AE),the integrated triaxial compression experiments were carried out on granitic specimens.The crack initiation and damage stresses were determined by wave velocity,wave amplitude and AE methods,respectively.The discrepancy of stresses for crack initiation and damage identified by these methods were examined.Results showed that the confinement affected the peak stress and corresponding strain,and these two parameters increased with increasing confining pressure.The ultrasonic wave velocity and wave amplitude first increased and then remained relatively stable,and finally decreased with increasing axial compressive stress.The number of AE events stayed at a relatively low extent until axial stress approached the peak;after that,the AE accumulative counts skyrocketed to the maximum.It also shows that for a given confinement,the stresses for crack initiation and damage identified by the wave amplitude method were the smallest,followed those by AE method and wave velocity method.Moreover,the stresses for crack initiation and crack damage identified by these methods increased generally with confining pressures.However,the rate of increment of these two crack stresses decreased with increasing confining pressure.In addition,the slight decrease in these two crack stresses ratios was noticed with increasing confining pressure.The findings are helpful to understand the crack stresses of deep rocks,in terms of support of deep underground engineering.
基金supported by the Global Energy Interconnection Group Co.,Ltd.Science and Technology Project(Project No.101662224/Title:UHV large-capacity DC submarine cable key technology and roadmap research)the National Key R&D Program of China(2016YFB0900702)
文摘Power transmission across the sea is an important part of global energy interconnection(GEI).To support the construction of GEI and to serve the needs of future clean energy trans-sea transportation and offshore wind power development,this study a)analyzes the requirements of the GEI backbone network pertaining to direct current(DC)submarine cable technology,and b)defines the key technical and economic indices of ultrahigh-voltage direct current(UHVDC)submarine cable based on theoretical computations.The research is based on the thermoelectric coupling model and the finite element method.It is shown that the dielectric strength of the insulating materials of the±800 kV~±1100 kV/4000 MW^12000 MW UHVDC submarine cable(extrusion insulation)should be not less than 43~65 kV/mm,while the heat resistance is not less than 110°C.As the cost of submarine cable is 5~10 times higher than that of the overhead line,the project investment need to be decreased to a level within the economical carrying capacity to guarantee extensive applicability of the HVDC submarine cable technology.
基金supported by the State Grid Science & Technology Project (GEIGC-E-[2018]026)
文摘The demands for massive renewable energy integration, passive network power supply, and global energy interconnection have all gradually increased, posing new challenges for high voltage direct current(HVDC) power transmission systems, including more complex topology and increased diversity of bipolar HVDC transmission. This study proposes that these two factors have led to new requirements for HVDC control strategies. Moreover, due to the diverse applications of HVDC transmission technology, each station in the system has different requirements. Furthermore, the topology of the AC-DC converter is being continuously developed, revealing a trend towards hybrid converter stations.
文摘OBJECTIVE To investigate the potential malignant characteristics and pathogenesis of endometriosis as well as the role of human growth hormone and epidermal growth factor receptor in the pathogenesis of malignant transformation of endometriosis. METHODS The immunohistochemical S-P method was used to examine the expression of human growth hormone and epidermal growth factor receptor in the eutopic and ectopic endometrium of 84 cases of endometriosis. RESULTS The percentage of positive cases of human growth hormone in eutopic and ectopic endometrium was 90.77% （59/65） and 85.71% （72/ 84） respectively. The percentage of positive cases of epidermal growth factor receptor in eutopic and ectopic endometrium was 81.54% （53/65） and 89.29% （75/84） respectively. The positive rate of epidermal growth factor receptor in ectopic endometrium was higher than that in the eutopic endometrium but without a statistically significant difference （P〉 0.05）. CONCLUSION Endometriosis is caused by multiple factors, which possesses some biologic features of neoplastic tissue such as invasion and metastasis. Both human growth hormone and epidermal growth factor receptor are highly expressed in eutopic and ectopic endometrium, which lead directly or indirectly to the pathogenesis of endometriosis and promote the initiation and malignant transformation of endometriosis.
基金supported by the National Natural Science Foundation of China(Grant No.61705025)the Natural Science Foundation of Heilongjiang Province,China(Grant No.F2018027)+3 种基金partially supported by Chongqing Natural Science Foundation(Grant Nos.cstc2019jcyj-msxmX0431 and cstc2018jcyjAX0817)the Science and Technology Project Affiliated to the Education Department of Chongqing Municipality(Grant Nos.KJQN201801217,KJQN201901226,and KJ1710247)Chongqing Key Laboratory of Geological Environment Monitoring and Disaster Early-Warning in Three Gorges Reservoir Area(Grant Nos.ZD2020A0103 and ZD2020A0102)the Fundamental Research Funds for Chongqing Three Gorges University of China(Grant No.19ZDPY08).
文摘In order to control the working wavelength range of the fiber surface plasmon resonance(SPR)temperature sensor and realize the wavelength division multiplexing type multi-channel fiber SPR temperature sensor,by comprehensively investigating the influence of liquids with different thermal-optical coefficients and solid packaging materials on the performance of fiber SPR temperature sensor,a dual-channel fiber SPR temperature sensor based on liquid-solid cascade encapsulation was designed and fabricated.The liquid temperature sensing stage encapsulated in capillary worked in 616.03 nm-639.05 nm band,the solid sensing stage coated with pouring sealant worked in 719.37 nm-825.27 nm band,and the two stages were cascaded to form a fiber dual-channel temperature sensor.The testing results indicated that when the temperature range was 35℃-95℃,the sensitivity of two-stage temperature detection was−0.384 nm/℃and−1.765 nm/℃respectively.The proposed fiber sensor has simple fabrication and excellent performance which can be widely used in various fields of dual-channel temperature measurement and temperature compensation.
基金Project supported by the National Natural Science Foundation of China(Grant No.61705025)the Natural Science Foundation of Heilongjiang Province,China(Grant No.F2018027)+4 种基金the Fund from Chongqing Municipal Key Laboratory of Institutions of Higher Education(Grant No.20173)the Program of Chongqing Development and Reform Commission(Grant No.20171007)the Natural Science Foundation of Chongqing,China(Grant Nos.cstc2019jcyjmsxmX0431 and cstc2018jcyjAX0817)the Science and Technology Project Affiliated to the Education Department of Chongqing Municipality,China(Grant Nos.KJQN201801217,KJQN201901226,and KJ1710247)the Fundamental Research Funds for Chongqing Three Gorges University of China(Grant No.19ZDPY08)。
文摘A fiber cladding surface plasmon resonance(SPR)bending sensor is realized by the cladding of the fiber structure.By employing coating film,the sensing zone is protected and the toughness of the sensor increases.Three different sensing probes are tested,the experiment results indicate that the two parameters(wavelength sensitivity and light intensity sensitivity)sensing performances of the eccentric butt joint structures are superior to that of hetero-core structure,and the SPR bending sensor based on hetero-core structure is stable and uneasy to damage.By employing hetero-core fiber and silver film,a fiber cladding SPR bending sensor with better stabilization and sensing performance is realized.The proposed fabricating method of sensing probe with coating film provides a new approach for fiber SPR-distributed bending sensor.
基金supported by National Natural Science Foundation of China(Grant No.51337006)
文摘The current interruption capability of a gas, when used in high voltage gas-blast circuit breakers,depends not only on its material properties but also the flow field since turbulence plays a dominant role in arc cooling during the interruption process. Based on available experimental results, a study of CO2 switching arcs under a DC（direct current） current in the model circuit breaker has been conducted to calibrate CO2 arc model and to analyse its electric and thermal property. Through detailed analysis of the results mechanisms responsible for the temperature distribution are identified and the domain energy transportation process of different region discussed. The present work provides significant coefficients for CO2 switching arc simulation and gives a better understanding of CO2 arc burning mechanisms.
基金Key Technology Support Program of Sichuan Province(2018NZDZX0004,2016NZ0104)Financial Project of Sichuan Province(SASA2020CZYX002)。
文摘Sterol regulatory element-binding factor-1 and-2(SREBF1 and SREBF2)are important transcription factors involved in the regulating lipid homeostasis.Based on the essential role of SREBF1 and SREBF2,we measured the mRNA expression levels of the two genes in six various tissues at different growth points.Our results showed that the SREBF1 and SREBF2 were expressed in all six tissues examined in Erlang mountainous chicken(SD02)at 42 d,and were expressed abundantly in the uropygial gland and liver,with relatively lowest levels of expression in the abdominal fat,sebum cutaneum and leg muscle.The expression ratio of SREBF1 and SREBF2 in breast muscle,leg muscle,sebum cutaneum and uropygial gland exhibited a"decline-rise"trend.However,in liver,the expression ratio of these two genes exhibited a"decline-rise-decline"trend.Meanwhile,the expression level of SREBF1 gene of all tissues was lower than that of SREBF2 except for uropygial gland.The findings will provide important references for further function investigation of the two genes involved in fat deposition in chickens.
文摘[Objectives] The aim was to study the artificial cultivation of Bletilla striata to realize large scale and standardization planting. [Methods] The comparison tests were conducted on B. striata with different canopy densities of the Magnolia officinalis forests,different compound planting densities and different tending measures and management. [Results] When the stand canopy density was 0. 4-0. 6,the per unit yield of B. striata was 5. 4%,6. 8% higher than that at the canopy density of less than 0. 4 and more than 0. 6,respectively. When the planting density was 30 cm × 30 cm,the per unit yield increased by 16. 1%,12. 0%,13. 1% respectively compared with the planting density of 20 cm × 20 cm,25 cm × 25 cm,35 cm × 35 cm. When B. striata was planted from October to November,the per unit yield was 5. 6% higher than that planted from December to January of the following year,and 21. 3% higher than that from February to March of the second year. When farmyard manure was applied during the cultivation,the per unit yield was 31. 7% and 18. 4% higher than the application of chemical fertilizer and compound fertilizer. When weeding 4 times per year,the per unit yield increased by 240. 1%,137. 0% and 43. 9% respectively from that weeding 1 times,2 times,3 times per year. [Conclusions]When planting B. striata,the stand canopy density of 0. 4-0. 6 could make it receive absolutely shelters and the lighting conditions required for the growth,thereby bringing in high emergence rate,good growth potential and high yield. The best planting effect of B. striata could achieve by planting from October to November with the planting density of 30 cm × 30 cm,which can play the maximum benefit of individual plants. Moreover,weeding 4 times per year combined with the use of farmyard manure can promote the development and growth of tubers,which can greatly improve the yield of B. striata.
基金Supported by the National Key Research and Development Program of China(2022YFC2602203).
文摘Introduction:Plague is a zoonotic disease that occurs naturally in specific geographic areas.Climate change can influence the populations of the plague host or vector,leading to variations in the occurrence and epidemiology of plague in animals.Methods:In this study,we collected meteorological and plague epidemiological data from the Marmota himalayana plague focus in the Altun Mountains of the Qinghai-Xizang Plateau.The data spanned from 2000 to 2022.We describe the climatic factors and plague epidemic conditions and we describe their analysis by Pearson’s correlation.Results:During the period from 2000 to 2022,the isolation rates of Yersinia pestis(Y.pestis)from marmots and fleas were 9.27%(451/4,864)and 7.17%(118/1,646),respectively.Additionally,we observed a positive rate of F1 antibody of 11.25%(443/3,937)in marmots and 18.16%(142/782)in dogs.With regards to climate,there was little variation,and a decreasing trend in blowing-sand days was observed.The temperature in the previous year showed a negative correlation with the Y.pestis isolation rate in marmots(r=−0.555,P=0.011)and the positive rate of F1 antibody in marmots(r=−0.552,P=0.012)in the current year.The average annual precipitation in the previous two years showed a positive correlation with marmot density(r=0.514,P=0.024),while blowingsand days showed a negative correlation with marmot density(r=−0.701,P=0.001).Furthermore,the average annual precipitation in the previous three years showed a positive correlation with the isolation rate of Y.pestis from marmots(r=0.666,P=0.003),and blowing-sand days showed a negative correlation with marmot density(r=−0.597,P=0.009).Conclusions:The findings of this study indicate that there is a hysteresis effect of climate change on the prevalence of plague.Therefore,monitoring climate conditions can offer significant insights for implementing timely preventive and control measures to combat plague epidemics.
