Metallothionein gene (MT) has been transferred into mushroom protoplasts by electroporation. It is a low molecular weight, cysteine-rich and metal-binding protein. MT can bind metals. Its synthesis is induced by Zn io...Metallothionein gene (MT) has been transferred into mushroom protoplasts by electroporation. It is a low molecular weight, cysteine-rich and metal-binding protein. MT can bind metals. Its synthesis is induced by Zn ion. Thus the expression of MT gene in mushroom can improve the accumulation of Zn in this fungus. This transgenic mushroom, consumed as a kind of vegetable, can supply the necessary Zn to people who are short of the element. When protoplasts were prepared, the concentration (C) of protoplasts is 6.745 x 10(6) /mL. After protoplast electroporation, the transformation rate of protoplasts is 0.01 %. Polymerase chain reaction (PCR) analysis showed that the gene had been integrated into the mushroom chromosome, SDS-PAGE, Western blot analysis indicated that the MT gene had been expressed in the transgenic mushroom. The expressing level, detected by ELISA, is 0.6 % - 0.8 %. Tested for metal resistance, the wild-type mushroom growth was inhibited on die medium containing 1.0 - 1.2 mmoL/L ZnSO4. While the transgenic mushroom was inhibited on the medium containing 1. 5 - 2.0 mmol/L ZnSO4. The mycelium can develop into hymenophore in the medium of rice bran: sawdust = 1: 3, and not in the medium of rice bran: sawdust = 1: 4.展开更多
In this paper, we present a new method for reducing seismic noise while preserving structural and stratigraphic discontinuities. Structure-oriented edge-preserving smoothing requires information such as the local orie...In this paper, we present a new method for reducing seismic noise while preserving structural and stratigraphic discontinuities. Structure-oriented edge-preserving smoothing requires information such as the local orientation and edge of the reflections. The information is usually estimated from seismic data with full frequency bandwidth. When the data has a very low signal to noise ratio （SNR）, the noise usually reduces the estimation accuracy. For seismic data with extremely low SNR, the dominant frequency has higher SNR than other frequencies, so it can provide orientation and edge information more reliably than other frequencies. Orientation and edge are usually described in terms of apparent reflection dips and coherence differences, respectively. When frequency changes, both dip and coherence difference change more slowly than the seismogram itself. For this reason, dip and coherence estimated from dominant frequency data can approximately represent those of other frequency data. Ricker wavelet are widely used in seismic modeling. The Marr wavelet has the same shape as Ricker wavelets in both time and frequency domains, so the Marr wavelet transform is selected to divide seismic data into several frequency bands. Reflection apparent dip as well as the edge information can be obtained by scanning the dominant frequency data. This information can be used to selectively smooth the frequency bands （dominant, low, and high frequencies） separately by structure-oriented edge-preserving smoothing technology. The ultimate noise-suppressed seismic data is the combination of the smoothed frequency band data. Application to synthetic and real data shows the method can effectively reduce noise, preserve edges, improve trackable reflection continuity, and maintain useful information in seismic data.展开更多
This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on ce...This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on certain sets,relax the restriction about the rate of change of state variable in a system to be bounded in Marachkov's theorem and extend the related results in [4—7].展开更多
The phase equilibria in Co-rich region of Co-Ti-Ta system were studied.The microstructure and XRD analysis together with EDS determination show that L12 type Co3Ti phase and Laves_C36_Co3Ta phase get equilibrium with ...The phase equilibria in Co-rich region of Co-Ti-Ta system were studied.The microstructure and XRD analysis together with EDS determination show that L12 type Co3Ti phase and Laves_C36_Co3Ta phase get equilibrium with α-Co phase from 1 000 to 1 200 ℃.The Co3Ti phase possesses a solubility of Ta higher than 10%,and the addition of Ta stabilizes the Co3Ti phase.The isothermal sections of the Co-Ti-Ta system in the Co-rich region at 1 000,1 100 and 1 200 ℃ were constructed according to the result.展开更多
This paper first develops the approaches to determine the geopotential of the local mean sea level,and then investigates the offset of the 1985 vertical datum surface defined by the mean sea level of Yellow Sea at the...This paper first develops the approaches to determine the geopotential of the local mean sea level,and then investigates the offset of the 1985 vertical datum surface defined by the mean sea level of Yellow Sea at the Dagang Tide Gauge in Qingdao city using the developed approaches and GPS/leveling data.It shows that the geopotential of the local mean sea level at the tide gauge is equal to 62 636 853.5±0.2 m2·s -2 and that the 1985 vertical datum surface is 24.6±5.4 cm above the geoid realized by the geopotential W 0= 62 636 856.0±0.5 m2·s -2.展开更多
[Objective]The aim was to discuss elimination mechanism and equilibrium model about complete linkage gene of panmixis based on fitness.[Method]A mathematical model that gsgenerational evalution of frequency of panmixi...[Objective]The aim was to discuss elimination mechanism and equilibrium model about complete linkage gene of panmixis based on fitness.[Method]A mathematical model that gsgenerational evalution of frequency of panmixis two pairs of complete linkage gene under difference fitness was built by using difference equations to study elimination mechanism and genetic equilibrium state of panncticcoinplete linkage gene.[Result]The panmixis is different from Hardy-Weinberg Equilibrium which reached the equilibrium just by one generation.A method that by using linear equation to calculate the frequency of four gametes and the fitnessed of panmixis was established after detormining is the fitness of 10 genotypes the necessary and sufficient condition of the panmixis to reach balance.[Conclusion]The method is valuable for reference on linkage disequilibrium and hitchhiking effect study.展开更多
文摘Metallothionein gene (MT) has been transferred into mushroom protoplasts by electroporation. It is a low molecular weight, cysteine-rich and metal-binding protein. MT can bind metals. Its synthesis is induced by Zn ion. Thus the expression of MT gene in mushroom can improve the accumulation of Zn in this fungus. This transgenic mushroom, consumed as a kind of vegetable, can supply the necessary Zn to people who are short of the element. When protoplasts were prepared, the concentration (C) of protoplasts is 6.745 x 10(6) /mL. After protoplast electroporation, the transformation rate of protoplasts is 0.01 %. Polymerase chain reaction (PCR) analysis showed that the gene had been integrated into the mushroom chromosome, SDS-PAGE, Western blot analysis indicated that the MT gene had been expressed in the transgenic mushroom. The expressing level, detected by ELISA, is 0.6 % - 0.8 %. Tested for metal resistance, the wild-type mushroom growth was inhibited on die medium containing 1.0 - 1.2 mmoL/L ZnSO4. While the transgenic mushroom was inhibited on the medium containing 1. 5 - 2.0 mmol/L ZnSO4. The mycelium can develop into hymenophore in the medium of rice bran: sawdust = 1: 3, and not in the medium of rice bran: sawdust = 1: 4.
基金supported by China National Petroleum Corporation (CNPC) Innovation Fund (Grant No.07E1019)Specialized Research Fund for the Doctoral Program of Higher Education (SRFDP) (Grant No.200804251502)
文摘In this paper, we present a new method for reducing seismic noise while preserving structural and stratigraphic discontinuities. Structure-oriented edge-preserving smoothing requires information such as the local orientation and edge of the reflections. The information is usually estimated from seismic data with full frequency bandwidth. When the data has a very low signal to noise ratio （SNR）, the noise usually reduces the estimation accuracy. For seismic data with extremely low SNR, the dominant frequency has higher SNR than other frequencies, so it can provide orientation and edge information more reliably than other frequencies. Orientation and edge are usually described in terms of apparent reflection dips and coherence differences, respectively. When frequency changes, both dip and coherence difference change more slowly than the seismogram itself. For this reason, dip and coherence estimated from dominant frequency data can approximately represent those of other frequency data. Ricker wavelet are widely used in seismic modeling. The Marr wavelet has the same shape as Ricker wavelets in both time and frequency domains, so the Marr wavelet transform is selected to divide seismic data into several frequency bands. Reflection apparent dip as well as the edge information can be obtained by scanning the dominant frequency data. This information can be used to selectively smooth the frequency bands （dominant, low, and high frequencies） separately by structure-oriented edge-preserving smoothing technology. The ultimate noise-suppressed seismic data is the combination of the smoothed frequency band data. Application to synthetic and real data shows the method can effectively reduce noise, preserve edges, improve trackable reflection continuity, and maintain useful information in seismic data.
文摘This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on certain sets,relax the restriction about the rate of change of state variable in a system to be bounded in Marachkov's theorem and extend the related results in [4—7].
基金Project (50771027) supported by the National Natural Science Foundation of China
文摘The phase equilibria in Co-rich region of Co-Ti-Ta system were studied.The microstructure and XRD analysis together with EDS determination show that L12 type Co3Ti phase and Laves_C36_Co3Ta phase get equilibrium with α-Co phase from 1 000 to 1 200 ℃.The Co3Ti phase possesses a solubility of Ta higher than 10%,and the addition of Ta stabilizes the Co3Ti phase.The isothermal sections of the Co-Ti-Ta system in the Co-rich region at 1 000,1 100 and 1 200 ℃ were constructed according to the result.
文摘This paper first develops the approaches to determine the geopotential of the local mean sea level,and then investigates the offset of the 1985 vertical datum surface defined by the mean sea level of Yellow Sea at the Dagang Tide Gauge in Qingdao city using the developed approaches and GPS/leveling data.It shows that the geopotential of the local mean sea level at the tide gauge is equal to 62 636 853.5±0.2 m2·s -2 and that the 1985 vertical datum surface is 24.6±5.4 cm above the geoid realized by the geopotential W 0= 62 636 856.0±0.5 m2·s -2.
基金Supported by Scientific Research Grant of the Education Department of Guangxi Zhuang Autonomous Region(200807MS065)Elite Support Fund for Universities in Guangxi Zhuang Autonomous Region~~
文摘[Objective]The aim was to discuss elimination mechanism and equilibrium model about complete linkage gene of panmixis based on fitness.[Method]A mathematical model that gsgenerational evalution of frequency of panmixis two pairs of complete linkage gene under difference fitness was built by using difference equations to study elimination mechanism and genetic equilibrium state of panncticcoinplete linkage gene.[Result]The panmixis is different from Hardy-Weinberg Equilibrium which reached the equilibrium just by one generation.A method that by using linear equation to calculate the frequency of four gametes and the fitnessed of panmixis was established after detormining is the fitness of 10 genotypes the necessary and sufficient condition of the panmixis to reach balance.[Conclusion]The method is valuable for reference on linkage disequilibrium and hitchhiking effect study.
