The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic fu...The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results.展开更多
Objective The purpose of this experiment was to investigate the effects of exogenous hormone factors on subculture multiplication and root induction of tis-suecultured seedlings in mulberry. [Method] The aseptic seedl...Objective The purpose of this experiment was to investigate the effects of exogenous hormone factors on subculture multiplication and root induction of tis-suecultured seedlings in mulberry. [Method] The aseptic seedlings of Guisangyou 12 were used as the materials and the comparative experiment on subculture multi-plication and root induction used different kinds,concentrations and combinations of exogenous hormones. [Result] The hormone combination of 0.1 mg/L IBA+1.5 mg/L 6-BA+0.03 mg/L TDZ showed the best effects to bud multiplication, and the multiple of bud multiplication was 5.28. The effects of NAA was better than IBA and IAA on root induction. The hormone combination of 2.0 mg/L NAA+1.0 mg/L PP333 was most suitable to the root induction, in which the rooting rate arrived to 100%, the root number was 7.01 and the root length was 1.38 cm on average. [Conclusion] The results wil provide some technical reference for large-scale propagation of mul-berry seedlings in vitro.展开更多
[Objective] This study aimed to shorten the multiplication culture and root- ing culture periods of Rh. chrysanthum Pall. [Method] The Rh. chrysanthum Pall tis- sue culture plantlets collected from Changbai Mountain w...[Objective] This study aimed to shorten the multiplication culture and root- ing culture periods of Rh. chrysanthum Pall. [Method] The Rh. chrysanthum Pall tis- sue culture plantlets collected from Changbai Mountain were used as material, and the effects of different hormone combinations and coconut milk on the proliferation and differentiation of Rh. chrysanthum Pall tissue culture plantlets were investigated. In addition, the rooting medium and transplanting matrix for Rh. chrysanthum Pall tissue culture plantlets were explored. [Result] The medium composed of modified MS, iBA (3 mg/L) and ZT (1.5 mg/L) was the optimum medium for subculture mul- tiplication of Rh. chrysanthum Pall tissue culture plantlets. The multiplication multiple and average plant height were significantly improved by adding coconut milk into the medium (150 mg/L). [Conclusion] For Rh. chrysanthum Pall tissue culture plantlets, the optimum rooting culture medium was composed of modified MS (1/4) and IBA (5.0 mg/L), and the tissue culture plantlets began to root 8 d after the inoculation. The root induction treatment was carried out after a 15-d sand culture, and the suitable matrix was composed of tufty soil, humus soil and perlite (2:1:1) with a survival rate of 95.66%.展开更多
[Objective] The aims was to explore PTGMS line purification and multipli- cation technology. [Method] Three commercial PTGMS lines, Annong 810S, P88S and C815S, were used in this study. In the first year, two sterile ...[Objective] The aims was to explore PTGMS line purification and multipli- cation technology. [Method] Three commercial PTGMS lines, Annong 810S, P88S and C815S, were used in this study. In the first year, two sterile line populations with same genetic background were multiplied by dividing seedling; meanwhile, se- lection and multiplication of the core individuals were conducted; within the year, the core seeds harvested were multiplied under the isolated condition in Hainan, and at the same time, superior individuals were selected and used as the seeds for two populations with same genetic background in the next year. In the second year, seeds harvested in Hainan were planted in Changsha, while the core individuals were selected and multiplied; the core seeds harvested were continued to multiply in Hainan. The above procedures were repeated in the following years. [Result] The test results showed that in two years the proportion of core individuals in the popu- lation of Annong 810S, P88S and C815S increased from 40.3%, 0.7% and 0.3% in the first year to 71.67%, 66.00% and 68.67% in the second year respectively. [Conclusion] This suggested that this method of purification and multiplication of the PTGMS lines for consecutive years can effectively control the drift of the critical sterility inducing temperature, and at the same time, core seeds with high purity and controlled inducing temperature can be harvested.展开更多
A preliminary feasibility study was set up for the HNBM standard system. By introducing the set theory and basic methods of the solid geometry and adopting the Verman three-dimensional structure ideology innovatively,...A preliminary feasibility study was set up for the HNBM standard system. By introducing the set theory and basic methods of the solid geometry and adopting the Verman three-dimensional structure ideology innovatively, the standards system of Hainan National Breeding and Multiplication (HNBM) was studied with the four-dimensional structure and integration by combining with the time dimension. The four-dimensional structure standards system will be useful for guiding the construction of the HNBM standards system, carrying on the division of labor and realizing the dynamic development of the standards system. The standards set of HNBM helps to computer programming and information management.展开更多
Based on the analysis of several familiar large integer modular multiplication algorithms, this paper proposes a new Scalable Hybrid modular multiplication (SHyb) algorithm which has scalable operands, and presents an...Based on the analysis of several familiar large integer modular multiplication algorithms, this paper proposes a new Scalable Hybrid modular multiplication (SHyb) algorithm which has scalable operands, and presents an RSA algorithm model with scalable key size. Theoretical analysis shows that SHyb algorithm requires m 2 n /2 + 2miterations to complete an mn-bit modular multiplication with the application of an n-bit modular addition hardware circuit. The number of the required iterations can be reduced to a half of that of the scalable Montgomery algorithm. Consequently, the application scope of the RSA cryptosystem is expanded and its operation speed is enhanced based on SHyb al- gorithm.展开更多
Based on winter nursery and shuttle breeding, Hainan National Breeding and Multiplication (HNBM), with off-season breeding and seed production as the essence, has become a national strategic resource. The way of HNB...Based on winter nursery and shuttle breeding, Hainan National Breeding and Multiplication (HNBM), with off-season breeding and seed production as the essence, has become a national strategic resource. The way of HNBM rising to the national strategy was analyzed through the aspects of technology features, historical characteristics, irreplaceability, function and value hierarchy, and the key problems. As the major achievement of the practice of scientific research and historical selec- tion, HNBM played an irreplaceable role in the climatic conditions, scientific breed- ing, and seed production in disaster relief, protecting the safety of the seed industry and Iocational advantages. Based on the analysis on the functions, values and ex- isted problems of HNBM, the function and value hierarchical structure of HNBM was established through introducing concepts of value engineering, industrial clusters and regional economy. But to fully achieve the industrial clustering development and functional values of HNBM, it needed to solve the key problems existed in top-level planning, experimental bases, system design, hardware construction and ecological security. Some suggestions were put forward in this paper, including setting up key scientific research protection zones, improving the regulations and policies safeguard mechanism and management system of HNBM, drawing up and carrying out the base development planning of HNBM, and striving for financial support from national policies.展开更多
To resist the side chaimel attacks of elliptic curve cryptography, a new fast and secure point multiplication algorithm is proposed. The algorithm is based on a particular kind of addition chains involving only additi...To resist the side chaimel attacks of elliptic curve cryptography, a new fast and secure point multiplication algorithm is proposed. The algorithm is based on a particular kind of addition chains involving only additions, providing a natural protection against side channel attacks. Moreover, the new addition formulae that take into account the specific structure of those chains making point multiplication very efficient are proposed. The point multiplication algorithm only needs 1 719 multiplications for the SAC260 of 160-bit integers. For chains of length from 280 to 260, the proposed method outperforms all the previous methods with a gain of 26% to 31% over double-and add, 16% to22% over NAF, 7% to 13% over4-NAF and 1% to 8% over the present best algorithm--double-base chain.展开更多
The avalanche multiplication principle of electron multiplication CCD (EMCCD) was discussed on the basis of single type of carrier, and the multiplication model was built by using a classic piecewise ionization rate m...The avalanche multiplication principle of electron multiplication CCD (EMCCD) was discussed on the basis of single type of carrier, and the multiplication model was built by using a classic piecewise ionization rate model and avalanche multiplication integral formula. Wolff's ionization rate model was selected according to the structure and the multiplication gate amplitude of the actual devices. Compared the theoretical result with the multiplication curve of the actual device, it was found that only enough fringing field strength and multiplication area length could lead to adequate signal charge multiplication. The relationship between the multiplication gate amplitude and the total gain of the cascaded boosting EMCCD can be conveniently determined by using this model.展开更多
This article is devoted to characterizing the boundedness and compactness of multiplication operators from Hardy spaces to weighted Bergman spaces in the unit ball of ■.
‘Candidatus Liberibacter asiaticus(CLas)’,which causes citrus Huanglongbing(HLB)disease,has not been successfully cultured in vitro to date.Here,a rapid multiplication system for CLas was established through in vitr...‘Candidatus Liberibacter asiaticus(CLas)’,which causes citrus Huanglongbing(HLB)disease,has not been successfully cultured in vitro to date.Here,a rapid multiplication system for CLas was established through in vitro regeneration of axillary buds from CLas-infected‘Changyecheng’sweet orange(Citrus sinensis Osbeck).Stem segments with a single axillary bud were cultured in vitro to allow CLas to multiply in the regenerating axillary buds.A high CLas titer was detected in the regenerated shoots on an optimized medium at 30 days after germination(DAG).This titer was 28.2-fold higher than in the midribs from CLas-infected trees growing in the greenhouse.To minimize contamination during in vitro regeneration,CLas-infected axillary buds were micrografted onto seedlings of‘Changyecheng’sweet orange and cultured in a liquid medium.In this culture,the titers of CLas in regenerated shoots rapidly increased from 7.5×10^(4)to 1.4×10^(8)cellsμg^(-1)of citrus DNA during the first 40 DAG.The percentages of shoots with>1×10^(8)CLas cellsμg^(-1)DNA were 30 and 40%at 30 and 40 DAG,respectively.Direct tissue blot immunoassay(DTBIA)indicated that the distribution of CLas was much more uniform in regenerated plantlets than in CLas-infected trees growing in the greenhouse.The disease symptoms in the plantlets were die-back,stunted growth,leaf necrosis/yellowing,and defoliation.The death rate of the plantlets was 82.0%at 60 DAG.Our results show that CLas can effectively multiply in citrus plantlests in vitro.This method will be useful for studying plant-HLB interactions and for rapid screening of therapeutic compounds against CLas in citrus.展开更多
This paper exploits coding to speed up computation offloading in a multi-server mobile edge computing(MEC)network with straggling servers and channel fading.The specific task we consider is to compute the product betw...This paper exploits coding to speed up computation offloading in a multi-server mobile edge computing(MEC)network with straggling servers and channel fading.The specific task we consider is to compute the product between a user-generated input data matrix and a large-scale model matrix that is stored distributively across the multiple edge nodes.The key idea of coding is to introduce computation redundancy to improve robustness against straggling servers and to create communication redundancy to improve reliability against channel fading.We utilize the hybrid design of maximum distance separable(MDS)coding and repetition coding.Based on the hybrid coding scheme,we conduct theoretical analysis on the average task uploading time,average edge computing time,and average output downloading time,respectively and then obtain the end-to-end task execution time.Numerical results demonstrate that when the task uploading phase or the edge computing phase is the performance bottleneck,the hybrid coding reduces to MDS coding;when the downlink transmission is the bottleneck,the hybrid coding reduces to repetition coding.The hybrid coding also outperforms the entangled polynomial coding that causes higher uplink and downlink communication loads.展开更多
With the rhizomes obtained from the germination of Cymbidium sinense ~ Cymbidium goeringii seeds as a material, the effects of different basic media and different plant growth regulators on the multiplication and diff...With the rhizomes obtained from the germination of Cymbidium sinense ~ Cymbidium goeringii seeds as a material, the effects of different basic media and different plant growth regulators on the multiplication and differentiation of rhizomes and rooting and transplanting of seedlings were investigated. The results showed that the basal medium more suitable for the multiplication and differentiation of rhizomes was 1/2MS; the medium more suitable for the multiplication and differentiation of rhizomes of the hybrid orchid was 1/2MS + 6 - BA 2.0 mg/L + KT 0.5 mg/L + NAA 0.05 mg/L; the medium more suitable for the rooting of the hybrid orchid was 1/2MS + IBA 0.5 mg/L; and after training of seedlings, transplanting was performed onto moss, and after 25 d, the survival rate was 95.6%.展开更多
We developed a shoot multiplication protocol for Syringa reticulata Blume vat. mandshurica Hara from in vitro cultured seedlings that derived from in vitro germinated seeds. The shoots could be induced on Murashige an...We developed a shoot multiplication protocol for Syringa reticulata Blume vat. mandshurica Hara from in vitro cultured seedlings that derived from in vitro germinated seeds. The shoots could be induced on Murashige and Skoog (MS) medium with proper plant growth regulator combinations of 6-benzylaminopurine (BA) and indole-3-butyric acid (IBA). The better medium for shoot multiplication and growth was MS + 5 mg L-1 BA + 0.5 mg L-1 IBA + 20 g L-1 sucrose + 7 g L-1 agar, and the corresponding shoot induction rate was 75 %. The plantlets grew well after rooting on I/2MS medium (macro-elements of MS medium are at half-strength) sup- plemented with 1 mg L-1 IBA, and the survival percentage was 〉80 % at 16 weeks after transplanting.展开更多
Electro dislocation multiplication and strain effect were investigated. TEM observation showed that when statically held for 15 min, the microstructure of dislocation cell in the specimens without current pulse turned...Electro dislocation multiplication and strain effect were investigated. TEM observation showed that when statically held for 15 min, the microstructure of dislocation cell in the specimens without current pulse turned to subgrains with few dislocations in cold rolled state, but when current pulse charged, there were a lot of dislocations although a more rapid recrystallization occurred concurrently; when deformed, the interior dislocations in the specimens without current pulse were annihilated due to dynamic recrystallization, but were not decreased in the current pulse charged specimens in dynamic recrystallization, instead increased. It is indicated that “electron wind” force created by current pulse produced a shear stress for dislocation slip, and caused a dislocation multiplication in static holding of 2091 Al Li alloy; when strain exerted, an additional shear stress was provided to increase the effect of current pulse on dislocation multiplication.展开更多
Let Mφ be the operator of multiplication by φ on a Hilbert space of functions analytic on the open unit disk. For an invariant subspace F for the multiplication operator Mz, we derive some spectral properties of the...Let Mφ be the operator of multiplication by φ on a Hilbert space of functions analytic on the open unit disk. For an invariant subspace F for the multiplication operator Mz, we derive some spectral properties of the multiplication operator Mφ : F→F. We characterize norm, spectrum, essential norm and essential spectrum of such operators when F has the codimension n property with n∈{1,2,...,+∞}.展开更多
The composite field multiplication is an important and complex module in symmetric cipher algorithms, and its realization performance directly restricts the processing speed of symmetric cipher algorithms. Based on th...The composite field multiplication is an important and complex module in symmetric cipher algorithms, and its realization performance directly restricts the processing speed of symmetric cipher algorithms. Based on the characteristics of composite field multiplication in symmetric cipher algorithms and the realization principle of its reconfigurable architectures, this paper describes the reconfigurable composite field multiplication over GF((2^8)k) (k=1,2,3,4) in RISC (reduced instruction set computer) processor and VLIW (very long instruction word) processor architecture, respectively. Through configuration, the architectures can realize the composite field multiplication over GF(2^8), GF ((2^8)2), GF((28)3) and GF((28)4) flexibly and efficiently. We simulated the function of circuits and synthesized the reconfigurable design based on the 0.18 μm CMOS (complementary metal oxide semiconductor) standard cell library and the comparison with other same kind designs. The result shows that the reconfigurable design proposed in the paper can provide higher efficiency under the premise of flexibility.展开更多
This paper gives a comprehensive method to do Elliptic Curve Scalar Multiplication with only x-coordinate. Explicit point operation formulae for all types of defining equations of the curves are derived. For each type...This paper gives a comprehensive method to do Elliptic Curve Scalar Multiplication with only x-coordinate. Explicit point operation formulae for all types of defining equations of the curves are derived. For each type of curve, the performance is analyzed. The formulae are applied in Montgomery Ladder to get scalar multiplication algorithm operated with only x-coordinate. The new scalar multiplication has the same security level and computation amount with protected binary scalar multiplication (PBSM) against side channel attack, and has the advantages of higher security and little memory needed.展开更多
The key operation in Elliptic Curve Cryptosystems(ECC) is point scalar multiplication. Making use of Frobenius endomorphism, Muller and Smart proposed two efficient algorithms for point scalar multiplications over eve...The key operation in Elliptic Curve Cryptosystems(ECC) is point scalar multiplication. Making use of Frobenius endomorphism, Muller and Smart proposed two efficient algorithms for point scalar multiplications over even or odd finite fields respectively. This paper reduces the corresponding multiplier by modulo Υk-1 +…+Υ+ 1 and improves the above algorithms. Implementation of our Algorithm 1 in Maple for a given elliptic curve shows that it is at least as twice fast as binary method. By setting up a precomputation table, Algorithm 2, an improved version of Algorithm 1, is proposed. Since the time for the precomputation table can be considered free, Algorithm 2 is about (3/2) log2 q - 1 times faster than binary method for an elliptic curve over展开更多
基金Supported by Natural Science Foundation of Guangdong Province in China(2018KTSCX161)。
文摘The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results.
基金Supported by Post-graduate Innovation Program of Guangxi(YCSZ2013007)~~
文摘Objective The purpose of this experiment was to investigate the effects of exogenous hormone factors on subculture multiplication and root induction of tis-suecultured seedlings in mulberry. [Method] The aseptic seedlings of Guisangyou 12 were used as the materials and the comparative experiment on subculture multi-plication and root induction used different kinds,concentrations and combinations of exogenous hormones. [Result] The hormone combination of 0.1 mg/L IBA+1.5 mg/L 6-BA+0.03 mg/L TDZ showed the best effects to bud multiplication, and the multiple of bud multiplication was 5.28. The effects of NAA was better than IBA and IAA on root induction. The hormone combination of 2.0 mg/L NAA+1.0 mg/L PP333 was most suitable to the root induction, in which the rooting rate arrived to 100%, the root number was 7.01 and the root length was 1.38 cm on average. [Conclusion] The results wil provide some technical reference for large-scale propagation of mul-berry seedlings in vitro.
基金Supported by Students'Innovation and Entrepreneurship Training Program of Yanbian University in 2015(ydbksky2015252)~~
文摘[Objective] This study aimed to shorten the multiplication culture and root- ing culture periods of Rh. chrysanthum Pall. [Method] The Rh. chrysanthum Pall tis- sue culture plantlets collected from Changbai Mountain were used as material, and the effects of different hormone combinations and coconut milk on the proliferation and differentiation of Rh. chrysanthum Pall tissue culture plantlets were investigated. In addition, the rooting medium and transplanting matrix for Rh. chrysanthum Pall tissue culture plantlets were explored. [Result] The medium composed of modified MS, iBA (3 mg/L) and ZT (1.5 mg/L) was the optimum medium for subculture mul- tiplication of Rh. chrysanthum Pall tissue culture plantlets. The multiplication multiple and average plant height were significantly improved by adding coconut milk into the medium (150 mg/L). [Conclusion] For Rh. chrysanthum Pall tissue culture plantlets, the optimum rooting culture medium was composed of modified MS (1/4) and IBA (5.0 mg/L), and the tissue culture plantlets began to root 8 d after the inoculation. The root induction treatment was carried out after a 15-d sand culture, and the suitable matrix was composed of tufty soil, humus soil and perlite (2:1:1) with a survival rate of 95.66%.
基金Supported by National High Technology Research and Development Program of China(2010AA101305,2011AA10A101)National Science and Technology Supporting Project(2012BAD48G01)~~
文摘[Objective] The aims was to explore PTGMS line purification and multipli- cation technology. [Method] Three commercial PTGMS lines, Annong 810S, P88S and C815S, were used in this study. In the first year, two sterile line populations with same genetic background were multiplied by dividing seedling; meanwhile, se- lection and multiplication of the core individuals were conducted; within the year, the core seeds harvested were multiplied under the isolated condition in Hainan, and at the same time, superior individuals were selected and used as the seeds for two populations with same genetic background in the next year. In the second year, seeds harvested in Hainan were planted in Changsha, while the core individuals were selected and multiplied; the core seeds harvested were continued to multiply in Hainan. The above procedures were repeated in the following years. [Result] The test results showed that in two years the proportion of core individuals in the popu- lation of Annong 810S, P88S and C815S increased from 40.3%, 0.7% and 0.3% in the first year to 71.67%, 66.00% and 68.67% in the second year respectively. [Conclusion] This suggested that this method of purification and multiplication of the PTGMS lines for consecutive years can effectively control the drift of the critical sterility inducing temperature, and at the same time, core seeds with high purity and controlled inducing temperature can be harvested.
文摘A preliminary feasibility study was set up for the HNBM standard system. By introducing the set theory and basic methods of the solid geometry and adopting the Verman three-dimensional structure ideology innovatively, the standards system of Hainan National Breeding and Multiplication (HNBM) was studied with the four-dimensional structure and integration by combining with the time dimension. The four-dimensional structure standards system will be useful for guiding the construction of the HNBM standards system, carrying on the division of labor and realizing the dynamic development of the standards system. The standards set of HNBM helps to computer programming and information management.
文摘Based on the analysis of several familiar large integer modular multiplication algorithms, this paper proposes a new Scalable Hybrid modular multiplication (SHyb) algorithm which has scalable operands, and presents an RSA algorithm model with scalable key size. Theoretical analysis shows that SHyb algorithm requires m 2 n /2 + 2miterations to complete an mn-bit modular multiplication with the application of an n-bit modular addition hardware circuit. The number of the required iterations can be reduced to a half of that of the scalable Montgomery algorithm. Consequently, the application scope of the RSA cryptosystem is expanded and its operation speed is enhanced based on SHyb al- gorithm.
基金Supported by the Natural Science Foundation of Hainan Province(313114)the Sanya Science Project(2013YD89)the Social Science Project(SYSK14-08)~~
文摘Based on winter nursery and shuttle breeding, Hainan National Breeding and Multiplication (HNBM), with off-season breeding and seed production as the essence, has become a national strategic resource. The way of HNBM rising to the national strategy was analyzed through the aspects of technology features, historical characteristics, irreplaceability, function and value hierarchy, and the key problems. As the major achievement of the practice of scientific research and historical selec- tion, HNBM played an irreplaceable role in the climatic conditions, scientific breed- ing, and seed production in disaster relief, protecting the safety of the seed industry and Iocational advantages. Based on the analysis on the functions, values and ex- isted problems of HNBM, the function and value hierarchical structure of HNBM was established through introducing concepts of value engineering, industrial clusters and regional economy. But to fully achieve the industrial clustering development and functional values of HNBM, it needed to solve the key problems existed in top-level planning, experimental bases, system design, hardware construction and ecological security. Some suggestions were put forward in this paper, including setting up key scientific research protection zones, improving the regulations and policies safeguard mechanism and management system of HNBM, drawing up and carrying out the base development planning of HNBM, and striving for financial support from national policies.
基金The National Natural Science Foundation of China (No.60473029,60673072).
文摘To resist the side chaimel attacks of elliptic curve cryptography, a new fast and secure point multiplication algorithm is proposed. The algorithm is based on a particular kind of addition chains involving only additions, providing a natural protection against side channel attacks. Moreover, the new addition formulae that take into account the specific structure of those chains making point multiplication very efficient are proposed. The point multiplication algorithm only needs 1 719 multiplications for the SAC260 of 160-bit integers. For chains of length from 280 to 260, the proposed method outperforms all the previous methods with a gain of 26% to 31% over double-and add, 16% to22% over NAF, 7% to 13% over4-NAF and 1% to 8% over the present best algorithm--double-base chain.
文摘The avalanche multiplication principle of electron multiplication CCD (EMCCD) was discussed on the basis of single type of carrier, and the multiplication model was built by using a classic piecewise ionization rate model and avalanche multiplication integral formula. Wolff's ionization rate model was selected according to the structure and the multiplication gate amplitude of the actual devices. Compared the theoretical result with the multiplication curve of the actual device, it was found that only enough fringing field strength and multiplication area length could lead to adequate signal charge multiplication. The relationship between the multiplication gate amplitude and the total gain of the cascaded boosting EMCCD can be conveniently determined by using this model.
基金Supported by the National Natural Science Foundation of China(11601400 and 11771441)the Fundamental Research Funds for the Central Universities(2017IB012 and 2017IVB064)
文摘This article is devoted to characterizing the boundedness and compactness of multiplication operators from Hardy spaces to weighted Bergman spaces in the unit ball of ■.
基金supported by the National Key R&D Program of China (2018YFD0201500 and 2018YFD1000300)the National Natural Science Foundation of China (31972393)the China Agriculture Research System of MOF and MARA (CARS-26)
文摘‘Candidatus Liberibacter asiaticus(CLas)’,which causes citrus Huanglongbing(HLB)disease,has not been successfully cultured in vitro to date.Here,a rapid multiplication system for CLas was established through in vitro regeneration of axillary buds from CLas-infected‘Changyecheng’sweet orange(Citrus sinensis Osbeck).Stem segments with a single axillary bud were cultured in vitro to allow CLas to multiply in the regenerating axillary buds.A high CLas titer was detected in the regenerated shoots on an optimized medium at 30 days after germination(DAG).This titer was 28.2-fold higher than in the midribs from CLas-infected trees growing in the greenhouse.To minimize contamination during in vitro regeneration,CLas-infected axillary buds were micrografted onto seedlings of‘Changyecheng’sweet orange and cultured in a liquid medium.In this culture,the titers of CLas in regenerated shoots rapidly increased from 7.5×10^(4)to 1.4×10^(8)cellsμg^(-1)of citrus DNA during the first 40 DAG.The percentages of shoots with>1×10^(8)CLas cellsμg^(-1)DNA were 30 and 40%at 30 and 40 DAG,respectively.Direct tissue blot immunoassay(DTBIA)indicated that the distribution of CLas was much more uniform in regenerated plantlets than in CLas-infected trees growing in the greenhouse.The disease symptoms in the plantlets were die-back,stunted growth,leaf necrosis/yellowing,and defoliation.The death rate of the plantlets was 82.0%at 60 DAG.Our results show that CLas can effectively multiply in citrus plantlests in vitro.This method will be useful for studying plant-HLB interactions and for rapid screening of therapeutic compounds against CLas in citrus.
基金supported by NSF of China under grant U1908210National Key R&D Project of China under grant 2019YFB1802702。
文摘This paper exploits coding to speed up computation offloading in a multi-server mobile edge computing(MEC)network with straggling servers and channel fading.The specific task we consider is to compute the product between a user-generated input data matrix and a large-scale model matrix that is stored distributively across the multiple edge nodes.The key idea of coding is to introduce computation redundancy to improve robustness against straggling servers and to create communication redundancy to improve reliability against channel fading.We utilize the hybrid design of maximum distance separable(MDS)coding and repetition coding.Based on the hybrid coding scheme,we conduct theoretical analysis on the average task uploading time,average edge computing time,and average output downloading time,respectively and then obtain the end-to-end task execution time.Numerical results demonstrate that when the task uploading phase or the edge computing phase is the performance bottleneck,the hybrid coding reduces to MDS coding;when the downlink transmission is the bottleneck,the hybrid coding reduces to repetition coding.The hybrid coding also outperforms the entangled polynomial coding that causes higher uplink and downlink communication loads.
基金Supported by Technical Research and Development and Demonstration Promotion Fund of Beijing Vocational College of Agriculture(XY-YF-13-05)
文摘With the rhizomes obtained from the germination of Cymbidium sinense ~ Cymbidium goeringii seeds as a material, the effects of different basic media and different plant growth regulators on the multiplication and differentiation of rhizomes and rooting and transplanting of seedlings were investigated. The results showed that the basal medium more suitable for the multiplication and differentiation of rhizomes was 1/2MS; the medium more suitable for the multiplication and differentiation of rhizomes of the hybrid orchid was 1/2MS + 6 - BA 2.0 mg/L + KT 0.5 mg/L + NAA 0.05 mg/L; the medium more suitable for the rooting of the hybrid orchid was 1/2MS + IBA 0.5 mg/L; and after training of seedlings, transplanting was performed onto moss, and after 25 d, the survival rate was 95.6%.
基金supported by the Special Funding for Distinguished Researchers by Northeast Forestry University,China
文摘We developed a shoot multiplication protocol for Syringa reticulata Blume vat. mandshurica Hara from in vitro cultured seedlings that derived from in vitro germinated seeds. The shoots could be induced on Murashige and Skoog (MS) medium with proper plant growth regulator combinations of 6-benzylaminopurine (BA) and indole-3-butyric acid (IBA). The better medium for shoot multiplication and growth was MS + 5 mg L-1 BA + 0.5 mg L-1 IBA + 20 g L-1 sucrose + 7 g L-1 agar, and the corresponding shoot induction rate was 75 %. The plantlets grew well after rooting on I/2MS medium (macro-elements of MS medium are at half-strength) sup- plemented with 1 mg L-1 IBA, and the survival percentage was 〉80 % at 16 weeks after transplanting.
文摘Electro dislocation multiplication and strain effect were investigated. TEM observation showed that when statically held for 15 min, the microstructure of dislocation cell in the specimens without current pulse turned to subgrains with few dislocations in cold rolled state, but when current pulse charged, there were a lot of dislocations although a more rapid recrystallization occurred concurrently; when deformed, the interior dislocations in the specimens without current pulse were annihilated due to dynamic recrystallization, but were not decreased in the current pulse charged specimens in dynamic recrystallization, instead increased. It is indicated that “electron wind” force created by current pulse produced a shear stress for dislocation slip, and caused a dislocation multiplication in static holding of 2091 Al Li alloy; when strain exerted, an additional shear stress was provided to increase the effect of current pulse on dislocation multiplication.
文摘Let Mφ be the operator of multiplication by φ on a Hilbert space of functions analytic on the open unit disk. For an invariant subspace F for the multiplication operator Mz, we derive some spectral properties of the multiplication operator Mφ : F→F. We characterize norm, spectrum, essential norm and essential spectrum of such operators when F has the codimension n property with n∈{1,2,...,+∞}.
基金Supported by the National Natural Science Foundation of China(61202492,61309022,61309008)the Natural Science Foundation for Young of Shaanxi Province(2013JQ8013)
文摘The composite field multiplication is an important and complex module in symmetric cipher algorithms, and its realization performance directly restricts the processing speed of symmetric cipher algorithms. Based on the characteristics of composite field multiplication in symmetric cipher algorithms and the realization principle of its reconfigurable architectures, this paper describes the reconfigurable composite field multiplication over GF((2^8)k) (k=1,2,3,4) in RISC (reduced instruction set computer) processor and VLIW (very long instruction word) processor architecture, respectively. Through configuration, the architectures can realize the composite field multiplication over GF(2^8), GF ((2^8)2), GF((28)3) and GF((28)4) flexibly and efficiently. We simulated the function of circuits and synthesized the reconfigurable design based on the 0.18 μm CMOS (complementary metal oxide semiconductor) standard cell library and the comparison with other same kind designs. The result shows that the reconfigurable design proposed in the paper can provide higher efficiency under the premise of flexibility.
基金Supported by Natural Science Basic Research Plan in Shaanxi Province of China(2005F28)
文摘This paper gives a comprehensive method to do Elliptic Curve Scalar Multiplication with only x-coordinate. Explicit point operation formulae for all types of defining equations of the curves are derived. For each type of curve, the performance is analyzed. The formulae are applied in Montgomery Ladder to get scalar multiplication algorithm operated with only x-coordinate. The new scalar multiplication has the same security level and computation amount with protected binary scalar multiplication (PBSM) against side channel attack, and has the advantages of higher security and little memory needed.
基金Supported by the National Natural Science Foundation of China(No.90104004) the National 973 High Technology Projects(No.G1998030420)
文摘The key operation in Elliptic Curve Cryptosystems(ECC) is point scalar multiplication. Making use of Frobenius endomorphism, Muller and Smart proposed two efficient algorithms for point scalar multiplications over even or odd finite fields respectively. This paper reduces the corresponding multiplier by modulo Υk-1 +…+Υ+ 1 and improves the above algorithms. Implementation of our Algorithm 1 in Maple for a given elliptic curve shows that it is at least as twice fast as binary method. By setting up a precomputation table, Algorithm 2, an improved version of Algorithm 1, is proposed. Since the time for the precomputation table can be considered free, Algorithm 2 is about (3/2) log2 q - 1 times faster than binary method for an elliptic curve over