In this paper,we present a new method for seismic stratigraphic absorption compensation based on the adaptive molecular decomposition.Using this method,we can remove most of the effects resulting from wavelets truncat...In this paper,we present a new method for seismic stratigraphic absorption compensation based on the adaptive molecular decomposition.Using this method,we can remove most of the effects resulting from wavelets truncation and interference which usually exist in the common time-frequency absorption compensation method.Based on the assumption that the amplitude spectrum of the source wavelet is smooth,we first construct a set of adaptive Gabor frames based on the time-variant properties of the seismic signal to transform the signal into the time-frequency domain and then extract the slowly varying component（the wavelet＇s time-varying amplitude spectrum） in each window in the timefrequency domain.Then we invert the absorption compensation filter parameters with an objective function defined using the correlation coefficients in each window to get the corresponding compensation filters.Finally,we use these filters to compensate the timefrequency spectrum in each window and then transform the time-frequency spectrum to the time domain to obtain the absorption-compensated signal.By using adaptive molecular decomposition,this method can adapt to isolated and overlapped seismic signals from the complex layers in the inhomogeneous viscoelastic medium.The viability of the method is verified by synthetic and real data sets.展开更多
[Objective] The aim was to investigate the dimer formation between the movement proteins（MP）in barely yellow dwarf virus by using the technology of bimolecular fluorescence complementation technology and to further ...[Objective] The aim was to investigate the dimer formation between the movement proteins（MP）in barely yellow dwarf virus by using the technology of bimolecular fluorescence complementation technology and to further study the relationship between MP homodimerization and viral movement.[Method] The DNA sequence of bimolecular fluorescent complementary vector containing cloning multiple cloning sites,35S promoter and terminator was cloned into the expression vector pCAMBIA1300,which replicates at a higher copy number in E.coli.Then,the BYDV-MP gene fragment was amplified in the presence of the whole BYDV-PAV cDNA sequence as template and the primers designed according to the BYDV-MP gene sequence from GenBank,cloned into the modified bimolecular fluorescent complementary vectors pCAMBIA1300-NE and pCAMBIA1300-CE.The resulting vectors were transformed into Agrobacterium by electroporation method and infiltrated into the tobacco leaf.Protein interactions were observed under fluorescence microscope.[Result] Yellow fluorescence could be viewed in the leaves co-infiltrated with Agrobacterium carrying pCAMBIA1300NE-MP and pCAMBIA1300CE-MP at 2-5 d post-infiltration,while yellow fluorescence could not be observed in negative control groups.[Conclusion] BYDV-MP formed homodimers in plant cells.The results can provide theoretical basis for further in-depth research about the movement process and mechanism of BYDV.展开更多
Foaming reduces the working volume and limits the biosynthesis of macrolide immunosuppressant ascomycin(FK520) in the batch fermentation process of Streptomyces hygroscopicus FS-35 in a 7.5 L bioreactor. To find the r...Foaming reduces the working volume and limits the biosynthesis of macrolide immunosuppressant ascomycin(FK520) in the batch fermentation process of Streptomyces hygroscopicus FS-35 in a 7.5 L bioreactor. To find the relation between FK520 production and foaming, effects of 10 fermentation parameters including organic acids and membrane permeability were investigated. The results suggest that acetate accumulation caused by short period oxygen de ficiency and fast consumption of glucose is the reason for increased foaming and declined FK520 production. Therefore, a fed-batch fermentation strategy was developed to reduce the accumulation of acetate. After optimization, the maximum acetate concentration dropped from 320 mg·L-1to 157 mg·L-1, decreased by 50.8%, and the maximum foam height reduced from 5.32 cm to 3.74 cm, decreased by 29.7%, while the maximum FK520 production increased from 375 mg·L-1to 421 mg·L-1, improved by 12%.展开更多
We develop a quantum key distribution (QKD) system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a plug-and-play QKD ...We develop a quantum key distribution (QKD) system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a plug-and-play QKD system. The system monitors changes in key rates and controls it is own operation automatically. The system achieves its optimal performance within three seconds of operation, which includes a sifted key rate of 5.5 kbps and a quantum bit error rate of less than 2% after an abrupt temperature variation along the 25 km quantum channel. The system also operates well over a 24 h period while completing more than 60 active optical path length compensations.展开更多
Direct integration of high-mobility III-V compound semiconductors with existing Si-based complementary metal-oxide-semiconductor （CMOS） processing platforms presents the main challenge to increasing the CMOS perform...Direct integration of high-mobility III-V compound semiconductors with existing Si-based complementary metal-oxide-semiconductor （CMOS） processing platforms presents the main challenge to increasing the CMOS performance and the scaling trend. Silicon hetero-nanowires with integrated III-V segments are one of the most promising candidates for advanced nano-optoelectronics, as first demonstrated using molecular beam epitaxy techniques. Here we demonstrate a novel route for InAs/Si hybrid nanowire fabrication via millisecond range liquid-phase epitaxy regrowth using sequential ion beam implantation and flash-lamp annealing. We show that such highly mismatched systems can be monolithically integrated within a single nanowire. Optical and microstructural investigations confirm the high quality hetero-nanowire fabrication coupled with the formation of atomically sharp interfaces between Si and InAs segments. Such hybrid systems open new routes for future high-speed and multifunctional nanoelectronic devices on a single chip.展开更多
基金supported by the National 863 Program of China (Grant No.2006A09A102)National Natural Science Foundation of China (Grant No.40730424)Important National Science & Technology Specific Projects (Grant No.2008ZX05023005005)
文摘In this paper,we present a new method for seismic stratigraphic absorption compensation based on the adaptive molecular decomposition.Using this method,we can remove most of the effects resulting from wavelets truncation and interference which usually exist in the common time-frequency absorption compensation method.Based on the assumption that the amplitude spectrum of the source wavelet is smooth,we first construct a set of adaptive Gabor frames based on the time-variant properties of the seismic signal to transform the signal into the time-frequency domain and then extract the slowly varying component（the wavelet＇s time-varying amplitude spectrum） in each window in the timefrequency domain.Then we invert the absorption compensation filter parameters with an objective function defined using the correlation coefficients in each window to get the corresponding compensation filters.Finally,we use these filters to compensate the timefrequency spectrum in each window and then transform the time-frequency spectrum to the time domain to obtain the absorption-compensated signal.By using adaptive molecular decomposition,this method can adapt to isolated and overlapped seismic signals from the complex layers in the inhomogeneous viscoelastic medium.The viability of the method is verified by synthetic and real data sets.
基金Supported by National Natural Science Foundation of China(30870109)~~
文摘[Objective] The aim was to investigate the dimer formation between the movement proteins（MP）in barely yellow dwarf virus by using the technology of bimolecular fluorescence complementation technology and to further study the relationship between MP homodimerization and viral movement.[Method] The DNA sequence of bimolecular fluorescent complementary vector containing cloning multiple cloning sites,35S promoter and terminator was cloned into the expression vector pCAMBIA1300,which replicates at a higher copy number in E.coli.Then,the BYDV-MP gene fragment was amplified in the presence of the whole BYDV-PAV cDNA sequence as template and the primers designed according to the BYDV-MP gene sequence from GenBank,cloned into the modified bimolecular fluorescent complementary vectors pCAMBIA1300-NE and pCAMBIA1300-CE.The resulting vectors were transformed into Agrobacterium by electroporation method and infiltrated into the tobacco leaf.Protein interactions were observed under fluorescence microscope.[Result] Yellow fluorescence could be viewed in the leaves co-infiltrated with Agrobacterium carrying pCAMBIA1300NE-MP and pCAMBIA1300CE-MP at 2-5 d post-infiltration,while yellow fluorescence could not be observed in negative control groups.[Conclusion] BYDV-MP formed homodimers in plant cells.The results can provide theoretical basis for further in-depth research about the movement process and mechanism of BYDV.
基金Supported by the National Basic Research Program of China(2013CB733600)the Key Program of National Natural Science Foundation of China(21236005)+1 种基金the Natural Science Foundation of Tianjin(12JCZDJC21900)the Program of Introducing Talents of Discipline to Universities(B06006)
文摘Foaming reduces the working volume and limits the biosynthesis of macrolide immunosuppressant ascomycin(FK520) in the batch fermentation process of Streptomyces hygroscopicus FS-35 in a 7.5 L bioreactor. To find the relation between FK520 production and foaming, effects of 10 fermentation parameters including organic acids and membrane permeability were investigated. The results suggest that acetate accumulation caused by short period oxygen de ficiency and fast consumption of glucose is the reason for increased foaming and declined FK520 production. Therefore, a fed-batch fermentation strategy was developed to reduce the accumulation of acetate. After optimization, the maximum acetate concentration dropped from 320 mg·L-1to 157 mg·L-1, decreased by 50.8%, and the maximum foam height reduced from 5.32 cm to 3.74 cm, decreased by 29.7%, while the maximum FK520 production increased from 375 mg·L-1to 421 mg·L-1, improved by 12%.
基金was supported by the ICT R&D programs of Ministry of Science, ICT and Future Planning/Institute for Information & Communications Technology Promotion (Grant No. B0101-16-1355)the Korea Institute of Science and Technology research program (Grant No. 2E27231)Korea Institute of Science and Technology-Electronics And Telecommunications Research Institute research program (Grant No. 2V05340)
文摘We develop a quantum key distribution (QKD) system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a plug-and-play QKD system. The system monitors changes in key rates and controls it is own operation automatically. The system achieves its optimal performance within three seconds of operation, which includes a sifted key rate of 5.5 kbps and a quantum bit error rate of less than 2% after an abrupt temperature variation along the 25 km quantum channel. The system also operates well over a 24 h period while completing more than 60 active optical path length compensations.
文摘Direct integration of high-mobility III-V compound semiconductors with existing Si-based complementary metal-oxide-semiconductor （CMOS） processing platforms presents the main challenge to increasing the CMOS performance and the scaling trend. Silicon hetero-nanowires with integrated III-V segments are one of the most promising candidates for advanced nano-optoelectronics, as first demonstrated using molecular beam epitaxy techniques. Here we demonstrate a novel route for InAs/Si hybrid nanowire fabrication via millisecond range liquid-phase epitaxy regrowth using sequential ion beam implantation and flash-lamp annealing. We show that such highly mismatched systems can be monolithically integrated within a single nanowire. Optical and microstructural investigations confirm the high quality hetero-nanowire fabrication coupled with the formation of atomically sharp interfaces between Si and InAs segments. Such hybrid systems open new routes for future high-speed and multifunctional nanoelectronic devices on a single chip.
