[Objective] The aim was to establish an event-specific qualitative PCR method for transgenic soybean MON89788.[Method] Firstly,the 3′-junction sequence between host plant DNA and integrated DNA of transgenic MON89788...[Objective] The aim was to establish an event-specific qualitative PCR method for transgenic soybean MON89788.[Method] Firstly,the 3′-junction sequence between host plant DNA and integrated DNA of transgenic MON89788 soybean was isolated using thermal asymmetric interlaced-PCR (TAIL-PCR),and the specific PCR primers were designed based on the 3′-junction sequence.Secondly,the specificity and sensitivity of the qualitative PCR detection methods employing these primers were tested.[Result] 1 142-bp 3′-junction sequence was obtained.According to the sequence,event-specific qualitative PCR method was established,amplifying a 170-bp product specifically from MON89788 event,and the limit of detection was 0.05%,approximately 40 initial template copies.[Conclusion] The method was highly specific,sensitive,and suitable for detection of MON89788 event.展开更多
The solid-liquid interracial morphology evolution was investigated in directional solidification (DS) of Al-1.5%Cu alloy (mass fraction). The results show that the solidified microstructural evolution is gradual o...The solid-liquid interracial morphology evolution was investigated in directional solidification (DS) of Al-1.5%Cu alloy (mass fraction). The results show that the solidified microstructural evolution is gradual other than sharp, and the microstructure patterns are interesting and diversiform at the pulling rate ranging from 30 μm/s to 1500 μm/s. Indeed, dendrite to cell transition follows this sequence: dendrites→→banded cellular dendrites→elongated cells and part of dendrites→main elongated cells and little dendrites. Moreover, the present microstructure is not normal microstructure as we saw before. Further, according to the experimental phenomenon, the dendrite to cell transition was studied theoretically. Dendrite tip shape is an important parameter to characterize the dendrite to cell transition. As the dendrite to cell transition is far from equilibrium solidification, non-equilibrium solidification is taken into consideration in calculation. Finally, it is speculated that the dendrite to cell transition would occur at the minimum tip radius.展开更多
[Objective] The study was to investigate roles of Brassica napus EINB in ( BnEIN3 ) resistance to Sclerotinia sclerotiorum. [ Methods] Genomic PCR and RT-PCR were carded out to isolate genomic DNA and cDNA sequences...[Objective] The study was to investigate roles of Brassica napus EINB in ( BnEIN3 ) resistance to Sclerotinia sclerotiorum. [ Methods] Genomic PCR and RT-PCR were carded out to isolate genomic DNA and cDNA sequences of BnEIN3 from oilseed rape, based on the highly conserved region of EIN3 gene from Arabidopsis thaliana and the homologous sequences of oilseed rape ESTs. Expression levels of BnEIN3 were detected in three varieties of oilseed rape inoculated with S. sclerotiorum by real-time quantitative PCR.[Results] A 1 947 bp DNA fragment was obtained from oilseed rape. The fragment shared 82% identity to A. thaliana EIIV3, encoded 614 amino acids containing an EIN3 domain, and was named as BnEIN3. Real-time PCR results showed that expression patterns of BnEIN3 were drastically different in different varieties. In highly resistant oilseed rape variety D083, BnEIN3 expression level was significantly increased 72 h after S. sclerotiorum inoculation whereas in middle resistant and susceptible varieties Zhongshuang 9 and 84039, BnEIN3 expression was suppressed. [ Conclusion ] BnEIIV3 may play an important role in oilseed rape resistance to S. sclerotiorum.展开更多
[Objective] The study aimed to explore the method for directional breeding of a male-sterile line in oval-ecotype Chinese cabbage. [Method] Based on "Multiple Allele Hypothesis of Genic Male Sterile Chinese Cabbage"...[Objective] The study aimed to explore the method for directional breeding of a male-sterile line in oval-ecotype Chinese cabbage. [Method] Based on "Multiple Allele Hypothesis of Genic Male Sterile Chinese Cabbage", an inbred line '06048' of oval ecotype was used as the receptor, and male fertile plant of 'AB12' was used as the donor line. Crossing, backcross, selfing, testcross and sibling were ap- plied to transfer the multiple alleles under the directional genetic model. [Result] Segregation ratio of every generation was consistent with theoretical value. A new male sterile line with 100% male sterility and '06048' horticultural traits was ob- tained successfully, which accomplished the transfer of male sterile multiple allele and horticultural characters of receptor line at the same time. [Conclusion] The re- search verifies that the model of directional transfer is feasible, provides a theoreti- cal basis for the directional transfer of Chinese cabbage with other horticultural traits whose genotype is msms. The model can also be applied to other Brassica crops, to generate genetic male sterile lines with specific botanical traits and high-quality economic traits.展开更多
A green-revertible albino mutant-Qiufeng M was found from the japonica rice (Oryza sativa L. ssp. japonica) Qiufeng in the field. The first three leaves of the mutant were albino with some green. The leaf color beca...A green-revertible albino mutant-Qiufeng M was found from the japonica rice (Oryza sativa L. ssp. japonica) Qiufeng in the field. The first three leaves of the mutant were albino with some green. The leaf color became pale green since the fourth leaf and the glume had the same phenomenon as the first three leaves. The measuring data of the pigment content confirmed the visually observed results. It truly had a remarkable changing process in the leaf color in Qiufeng M. Comparison of the main agronomic characters between Qiufeng and Qiufeng M indicated that the neck length and grain weight showed significant difference at the 1% level, and other characters were not different. Genetic analysis showed that the green-revertible albino trait was controlled by a single recessive nucleic gene. Using 209 recessive mutant individuals in the F2 population derived from the cross Pei'ai 64S × Qiufeng M, a gene, tentatively named gra(t), was located between the SSR markers of RM475 and RM2-22 on the long arm of chromosome 2. The genetic distance were 17.3 cM and 2.9 cM respectively.展开更多
A gene sequence coding for the precursor of Galanthus nivalis agglutinin (GNA) was modified by site-directed mutagenesis to change very low usage bias codons to higher usage bias ones for improvement of the gene expre...A gene sequence coding for the precursor of Galanthus nivalis agglutinin (GNA) was modified by site-directed mutagenesis to change very low usage bias codons to higher usage bias ones for improvement of the gene expression in transgenic tobacco (Nicotiana tabacum L.) plants. Results from Western blot analysis of some of the transgenic tobacco plants showed that the expression level of GNA in plants transformed with the modified gene GNA34m reached 0.25% of total soluble proteins, while that of the GNA34 gene transgenic plants was 0.17%. Since the GNA expression level increased, the aphid resistance of GNA34m transgenic plants were also enhanced significantly as judged by a 71.0% aphid population inhibition in insect bioassay of GNA34m transformed plants and 63.7% for the plants transformed with the natural GNA34 gene.展开更多
[Objective] The aim of this study was to study on expression of Bt protein in transgenic pest-resistant rice. [Method] Enzyme-linked immunosorbent assay (ELISA) was used to measure Bt protein expression in different...[Objective] The aim of this study was to study on expression of Bt protein in transgenic pest-resistant rice. [Method] Enzyme-linked immunosorbent assay (ELISA) was used to measure Bt protein expression in different tissues of transgenic pest-resistant rice at same growth stage. [Result] Absolute content of Bt protein from high to low was as follows: leaves 〉 immature seeds and glumes 〉 roots 〉 stems in different tissues of transgenic rice in grain-filling stage; Bt protein content of trans- genic rice changed a little in different growth stages (including tillering stage, booting stage, and grain-filling stage); in general, its level declined a little in later growth stage, but the resistibility would not be influenced significantly. [Conclusion] The ex- periment is significant for pest prevention and transgenic rice breeding.展开更多
The soft rot infected by pathogenic bacterium Erwinia aroideae Holland is one of the three serious diseases of Chinese cabbage ( Brassica pekinensis Rupr.). By constructing vector system of high frequency transformati...The soft rot infected by pathogenic bacterium Erwinia aroideae Holland is one of the three serious diseases of Chinese cabbage ( Brassica pekinensis Rupr.). By constructing vector system of high frequency transformation mediated by Agrobacterium tunefaciens EHA105, anti-bacterial peptide gene with strong bactericidal action to pathogenic bacteria was introduced into Chinese cabbage AB-81 self-bred line and the transgenic plants were obtained. PCR and Southern blotting detection showed that target gene was integrated into plant genome of Chinese cabbage. The tests of bacteriostasis action of the extract from transgenic plants in vitro, and the assay of disease-resistant of transgenic plantlets in the tube and the pot by perfusing inoculation with pathogenic bacteria showed obvious resistance to soft rot. This resistance can be a stable heredity by genetic analysis of generations of transgenic plants self-bred, separation ratio of its R, was 3:1. The resistance to Km and disease of soft rot was still kept in the R-5. These results indicated the possibility of breeding new varieties of anti-soft rot Chinese cabbage by transgenic plants as parents.展开更多
A multiple antenna GPS system integrated with MEMS-based INS is proposed by data fusion. The system is applied to attitude determination due to its high accuracy, the high output rate, low latency, quick initializatio...A multiple antenna GPS system integrated with MEMS-based INS is proposed by data fusion. The system is applied to attitude determination due to its high accuracy, the high output rate, low latency, quick initialization, and good robustness and redundancy. The mathematical method for realizing the system is given. The system can provide attitude and other navigation information even without GPS measurement for a period of time. Experimental results show that, under the condition of 200 Hz, the attitude, the position, the velocity, the acceleration, and the angular rate can achieve 0. 08°/s, 1.5 m, 0. 1 m/s, 0. 12 m/s^2 and 0. 1°/s.展开更多
[Objective] This study aimed to investigate the hereditary stability of sFat-1 transgenic pigs and the differences in disease susceptivity between sFat-1 transgenic pigs and non-transgenic pigs. [Method] The integrati...[Objective] This study aimed to investigate the hereditary stability of sFat-1 transgenic pigs and the differences in disease susceptivity between sFat-1 transgenic pigs and non-transgenic pigs. [Method] The integration of sFat-1 gene in pigs was detected by PCR; the infection of transgenic pig to pseudorabies, leptospirosis, swine dysentery, brucellosis, Mycobacterium tuberculosis, rotavirus and mycoplasma hyopneumoniae was detected by using ELISA and PCR. [Result] The positive ratio of F3 generation sFat-1 transgenic pigs was 18.5%; the susceptivity of positive sFat- 1 transgenic and negative pigs to seven infectious diseases showed no significant difference. [Conclusion] Exogenous gene in sFat-1 transgenic pigs can not be stably inherited. The overall physical condition of positive transgenic and negative pigs was similar.展开更多
This study was to investigate the efficiency and specificity of RNAi silencing on the expression of endogenous fad2 gene in transgenic line W-4. [Method] The relative expression of fad2 gene in seeds at different deve...This study was to investigate the efficiency and specificity of RNAi silencing on the expression of endogenous fad2 gene in transgenic line W-4. [Method] The relative expression of fad2 gene in seeds at different developmental stages of 7th, 14th, 21st and 28th day after flowering (DAF) as wel as the root, stem, leaf at winter seedling stages of both the transgenic line W-4 and non-transgenic control Westar by real-time fluorescence quantitative PCR. [Results] The results showed the relative expression of fad2 gene was gradual y increasing with the days after flowering in the seeds of the control Westar, while it was found decreasing significantly since the 21st DAF in the seeds of the line W-4. The decline was up to 60% in comparison with the control Westar. However, no significant difference in the relative expression of fad2 gene in other organs like root, stem and leaf was observed between transgenic line W-4 and non-transgenic control Westar. Fatty acid composition analysis showed the oleic acid desaturation parameter(ODP) in seeds of the line W-4 was 0.07 in average, decreased by nearly 75% than control Westar which was 0.24 in average, while no significant difference in the seedling root, stem and leaf was measured between transgenic rapeseed and control. [Conclusion] The results above validated that RNA interference in transgenic rapeseed W-4 is at a seed-specific manner, not interfering with fad2 gene expression in organs such as the root, stem and leaf. The study also found that the period of fad2 gene expres-sion decline was wel coincided with the expression of napin gene, both appeared at the 21st DAF, indicating that the expression of dsRNA of fad2 gene is precisely control ed by the napin promoter.展开更多
The experiments of primary and secondary instabilities with controlled excitation are carried out on a swept flat plate to study the process leading to the final breakdown of laminar flow. Two types of high frequency ...The experiments of primary and secondary instabilities with controlled excitation are carried out on a swept flat plate to study the process leading to the final breakdown of laminar flow. Two types of high frequency secondary instabilities are identified. The most amplified mode is centered about the inflection point of the crosswise profile of the boundary layer and is interpreted as inflectional instability, the other occurs in the one third of the boundary layer from the wall. The high frequency disturbances are highly amplified but they also saturate similarly to the primary and nonlinearly generated disturbances. Their main effect in the final breakdown seems interact with the disturbances is developed and thus widens the frequency spectrum to turbulent state.展开更多
The double directional solidification(DS) technique was developed to control the lamellar microstructures in primary β TiAl-Nb alloys.Polysynthetically twinned(PST) crystals with lamellar boundaries parallel to o...The double directional solidification(DS) technique was developed to control the lamellar microstructures in primary β TiAl-Nb alloys.Polysynthetically twinned(PST) crystals with lamellar boundaries parallel to or inclined 45o to the growth direction were achieved due to the complete peritectic transformation during directional solidification of the alloys with the dendritic solid/liquid interface.The PST crystals with aligned lamellar boundaries only parallel to the growth direction were produced when lamellar grains with lamellar boundaries in the same orientation were seeded by themselves under appropriate growth conditions.Low boron addition is harmful to align the lamellar orientation because of the growth of non-peritectic α phase.Due to the larger yttria particles and boride ribbons in the directionally solidified TiAl-Nb alloys,the tensile plastic elongations of the alloys are only close to 2%.展开更多
The muhi-body analysis of the aeroelastic stability of the tiltrotor aircraft is presented. Muhi-body dynamic differential equations are combined with the equations of the unsteady dynamic inflow model to establish th...The muhi-body analysis of the aeroelastic stability of the tiltrotor aircraft is presented. Muhi-body dynamic differential equations are combined with the equations of the unsteady dynamic inflow model to establish the complete unsteadily aeroelastic coupling analytical model of the tiltrotor. The stability of the tiltrotor in the helicopter mode is analyzed aiming at a semi span soft-inplane tihrotor model with an elastic wing. Parametric effects of the lag stiffness of blades and the flight speed are analyzed. Numerical simulations demonstrate that the multibody analytical model can analyze the aeroelastic stability of the tiltrotor aircraft in the helicopter mode.展开更多
Novel 2×2 torsion-mirror optical switch arrays are fabricated by using the mixed micromachining based on the surface and bulk silicon microelectronics,then are investigated electromechanically in applied direct a...Novel 2×2 torsion-mirror optical switch arrays are fabricated by using the mixed micromachining based on the surface and bulk silicon microelectronics,then are investigated electromechanically in applied direct and alternating electric fields.When the thickness of the elastic torsion beams suspending the aluminum coated polysilicon micro-mirrors of the switches in the arrays is about 1μm,the electrostatic yielding voltages for driving the mirrors to achieve their ON-state are in the range of 270~290V,and the minimum holding voltages for mirrors ON-state are found as 55V or so.Theoretical analysis manifests that the yielding voltage is more sensitive to beam thickness than other design parameters do about the torsion-mirror switch structures.The lifetime can reach 10 8 times.The estimated shortest switching time of the switches at least lasts for less than 2ms.The force analysis on the two kinds of new fiber self-holding structures integrated monolithically in the chip of the optical switch arrays indicates that the structures can feature self-fixing and self-aligning of optical fibers.展开更多
A 16 bit stereo audio novel stability fifth-order ∑△ A/D converter that consists of switched capacitor ∑△ modulators, a decimation filter, and a bandgap circuit is proposed. A method for the stabilization of a hig...A 16 bit stereo audio novel stability fifth-order ∑△ A/D converter that consists of switched capacitor ∑△ modulators, a decimation filter, and a bandgap circuit is proposed. A method for the stabilization of a high order single stage ∑△ modulator is also proposed. A new multistage comb filter is used for the front end decimation filter. The ∑△ A/D converter achieves a peak SNR of 96dB and a dynamic range of 96dB. The ADC was implemented in 0. 5μm 5V CMOS technology. The chip die area occupies only 4. 1mm × 2.4mm and dissipates 90mW.展开更多
[Objective] The aim was to select suitable gene for Chlorella identification and to identify the oil-producing microalgae.[Method] Four candidate gene sequences,the nuclear genomic rDNA of the 18S rRNA gene,internal t...[Objective] The aim was to select suitable gene for Chlorella identification and to identify the oil-producing microalgae.[Method] Four candidate gene sequences,the nuclear genomic rDNA of the 18S rRNA gene,internal transcribed spacer(ITS),internal transcribed spacer Ⅱ(ITS Ⅱ)and the chloroplast rbcL gene,were selected for Chlorella molecular identification.Through these four candidate genes,the genetic variability and distinguish ability between intra-species and inter-species was analyzed to choose the right genes for identification of the high oil-content Chlorella.On this basis,application of these gene segments were classified and identified for five fresh-water isolated Chlorella,which oil-content is more than 30%.[Result] ITS gene was a suitable gene because of its high variation and short fragment length,meanwhile its genetic distance intra-species(0.439 6±0.135 9)was larger than inter-species(0.045 7±0.084 3).Its sequence length varied between different species whereas highly conserved in the same species.By the application of ITS sequences,respectively,five high oil-content stains were identified as one C.vulgaris,two strains of C.sorokiniana and two strains of algae Chlorella sp.[Conclusion] This study had provided reference for the establishment of identification gene pool of Chlorella.展开更多
基金Supported by Important National Science & Technology Specific Pro-jects(2008ZX08012-001)~~
文摘[Objective] The aim was to establish an event-specific qualitative PCR method for transgenic soybean MON89788.[Method] Firstly,the 3′-junction sequence between host plant DNA and integrated DNA of transgenic MON89788 soybean was isolated using thermal asymmetric interlaced-PCR (TAIL-PCR),and the specific PCR primers were designed based on the 3′-junction sequence.Secondly,the specificity and sensitivity of the qualitative PCR detection methods employing these primers were tested.[Result] 1 142-bp 3′-junction sequence was obtained.According to the sequence,event-specific qualitative PCR method was established,amplifying a 170-bp product specifically from MON89788 event,and the limit of detection was 0.05%,approximately 40 initial template copies.[Conclusion] The method was highly specific,sensitive,and suitable for detection of MON89788 event.
基金Project(SKLSP201418)supported by the Fund of the State Key Laboratory of Solidification Processing in North China University of Technology,ChinaProjects(51171151,51331005)supported by the National Natural Science Foundation of China
文摘The solid-liquid interracial morphology evolution was investigated in directional solidification (DS) of Al-1.5%Cu alloy (mass fraction). The results show that the solidified microstructural evolution is gradual other than sharp, and the microstructure patterns are interesting and diversiform at the pulling rate ranging from 30 μm/s to 1500 μm/s. Indeed, dendrite to cell transition follows this sequence: dendrites→→banded cellular dendrites→elongated cells and part of dendrites→main elongated cells and little dendrites. Moreover, the present microstructure is not normal microstructure as we saw before. Further, according to the experimental phenomenon, the dendrite to cell transition was studied theoretically. Dendrite tip shape is an important parameter to characterize the dendrite to cell transition. As the dendrite to cell transition is far from equilibrium solidification, non-equilibrium solidification is taken into consideration in calculation. Finally, it is speculated that the dendrite to cell transition would occur at the minimum tip radius.
文摘[Objective] The study was to investigate roles of Brassica napus EINB in ( BnEIN3 ) resistance to Sclerotinia sclerotiorum. [ Methods] Genomic PCR and RT-PCR were carded out to isolate genomic DNA and cDNA sequences of BnEIN3 from oilseed rape, based on the highly conserved region of EIN3 gene from Arabidopsis thaliana and the homologous sequences of oilseed rape ESTs. Expression levels of BnEIN3 were detected in three varieties of oilseed rape inoculated with S. sclerotiorum by real-time quantitative PCR.[Results] A 1 947 bp DNA fragment was obtained from oilseed rape. The fragment shared 82% identity to A. thaliana EIIV3, encoded 614 amino acids containing an EIN3 domain, and was named as BnEIN3. Real-time PCR results showed that expression patterns of BnEIN3 were drastically different in different varieties. In highly resistant oilseed rape variety D083, BnEIN3 expression level was significantly increased 72 h after S. sclerotiorum inoculation whereas in middle resistant and susceptible varieties Zhongshuang 9 and 84039, BnEIN3 expression was suppressed. [ Conclusion ] BnEIIV3 may play an important role in oilseed rape resistance to S. sclerotiorum.
基金Supported by National Natural Science Foundation of China(31101551)Yunnan Provincial Natural Science Foundation(2010CD057)Special Fund for Agro-scientific Research in the Public Interest(201003029)~~
文摘[Objective] The study aimed to explore the method for directional breeding of a male-sterile line in oval-ecotype Chinese cabbage. [Method] Based on "Multiple Allele Hypothesis of Genic Male Sterile Chinese Cabbage", an inbred line '06048' of oval ecotype was used as the receptor, and male fertile plant of 'AB12' was used as the donor line. Crossing, backcross, selfing, testcross and sibling were ap- plied to transfer the multiple alleles under the directional genetic model. [Result] Segregation ratio of every generation was consistent with theoretical value. A new male sterile line with 100% male sterility and '06048' horticultural traits was ob- tained successfully, which accomplished the transfer of male sterile multiple allele and horticultural characters of receptor line at the same time. [Conclusion] The re- search verifies that the model of directional transfer is feasible, provides a theoreti- cal basis for the directional transfer of Chinese cabbage with other horticultural traits whose genotype is msms. The model can also be applied to other Brassica crops, to generate genetic male sterile lines with specific botanical traits and high-quality economic traits.
基金This work was supported by the Major Research Program on Technology of Agricultural Structure Adjustment (No. 05-01-05B)Jiangsu High Technology Program (No. BG2004301, BG2004304, and BG2005301).
文摘A green-revertible albino mutant-Qiufeng M was found from the japonica rice (Oryza sativa L. ssp. japonica) Qiufeng in the field. The first three leaves of the mutant were albino with some green. The leaf color became pale green since the fourth leaf and the glume had the same phenomenon as the first three leaves. The measuring data of the pigment content confirmed the visually observed results. It truly had a remarkable changing process in the leaf color in Qiufeng M. Comparison of the main agronomic characters between Qiufeng and Qiufeng M indicated that the neck length and grain weight showed significant difference at the 1% level, and other characters were not different. Genetic analysis showed that the green-revertible albino trait was controlled by a single recessive nucleic gene. Using 209 recessive mutant individuals in the F2 population derived from the cross Pei'ai 64S × Qiufeng M, a gene, tentatively named gra(t), was located between the SSR markers of RM475 and RM2-22 on the long arm of chromosome 2. The genetic distance were 17.3 cM and 2.9 cM respectively.
文摘A gene sequence coding for the precursor of Galanthus nivalis agglutinin (GNA) was modified by site-directed mutagenesis to change very low usage bias codons to higher usage bias ones for improvement of the gene expression in transgenic tobacco (Nicotiana tabacum L.) plants. Results from Western blot analysis of some of the transgenic tobacco plants showed that the expression level of GNA in plants transformed with the modified gene GNA34m reached 0.25% of total soluble proteins, while that of the GNA34 gene transgenic plants was 0.17%. Since the GNA expression level increased, the aphid resistance of GNA34m transgenic plants were also enhanced significantly as judged by a 71.0% aphid population inhibition in insect bioassay of GNA34m transformed plants and 63.7% for the plants transformed with the natural GNA34 gene.
基金Transgenic cry1C Novel Materials of Japonica Rice Resistant Against Snout Moth’s Larva Cultivated with Biotechnology (201205068)The National Program of Transgenic Variety Development of China (2011ZX08001-001)~~
文摘[Objective] The aim of this study was to study on expression of Bt protein in transgenic pest-resistant rice. [Method] Enzyme-linked immunosorbent assay (ELISA) was used to measure Bt protein expression in different tissues of transgenic pest-resistant rice at same growth stage. [Result] Absolute content of Bt protein from high to low was as follows: leaves 〉 immature seeds and glumes 〉 roots 〉 stems in different tissues of transgenic rice in grain-filling stage; Bt protein content of trans- genic rice changed a little in different growth stages (including tillering stage, booting stage, and grain-filling stage); in general, its level declined a little in later growth stage, but the resistibility would not be influenced significantly. [Conclusion] The ex- periment is significant for pest prevention and transgenic rice breeding.
文摘The soft rot infected by pathogenic bacterium Erwinia aroideae Holland is one of the three serious diseases of Chinese cabbage ( Brassica pekinensis Rupr.). By constructing vector system of high frequency transformation mediated by Agrobacterium tunefaciens EHA105, anti-bacterial peptide gene with strong bactericidal action to pathogenic bacteria was introduced into Chinese cabbage AB-81 self-bred line and the transgenic plants were obtained. PCR and Southern blotting detection showed that target gene was integrated into plant genome of Chinese cabbage. The tests of bacteriostasis action of the extract from transgenic plants in vitro, and the assay of disease-resistant of transgenic plantlets in the tube and the pot by perfusing inoculation with pathogenic bacteria showed obvious resistance to soft rot. This resistance can be a stable heredity by genetic analysis of generations of transgenic plants self-bred, separation ratio of its R, was 3:1. The resistance to Km and disease of soft rot was still kept in the R-5. These results indicated the possibility of breeding new varieties of anti-soft rot Chinese cabbage by transgenic plants as parents.
文摘A multiple antenna GPS system integrated with MEMS-based INS is proposed by data fusion. The system is applied to attitude determination due to its high accuracy, the high output rate, low latency, quick initialization, and good robustness and redundancy. The mathematical method for realizing the system is given. The system can provide attitude and other navigation information even without GPS measurement for a period of time. Experimental results show that, under the condition of 200 Hz, the attitude, the position, the velocity, the acceleration, and the angular rate can achieve 0. 08°/s, 1.5 m, 0. 1 m/s, 0. 12 m/s^2 and 0. 1°/s.
基金Supported by National Major Program of Genetically Modified Organism for New Species Cultivation of China(2011ZX08011-004)Project from Hubei Agricultural Science and Technology Innovation Center(2011-620-001-003)~~
文摘[Objective] This study aimed to investigate the hereditary stability of sFat-1 transgenic pigs and the differences in disease susceptivity between sFat-1 transgenic pigs and non-transgenic pigs. [Method] The integration of sFat-1 gene in pigs was detected by PCR; the infection of transgenic pig to pseudorabies, leptospirosis, swine dysentery, brucellosis, Mycobacterium tuberculosis, rotavirus and mycoplasma hyopneumoniae was detected by using ELISA and PCR. [Result] The positive ratio of F3 generation sFat-1 transgenic pigs was 18.5%; the susceptivity of positive sFat- 1 transgenic and negative pigs to seven infectious diseases showed no significant difference. [Conclusion] Exogenous gene in sFat-1 transgenic pigs can not be stably inherited. The overall physical condition of positive transgenic and negative pigs was similar.
基金Supported by Fund for National Rapeseed Research System(CARS-13)~~
文摘This study was to investigate the efficiency and specificity of RNAi silencing on the expression of endogenous fad2 gene in transgenic line W-4. [Method] The relative expression of fad2 gene in seeds at different developmental stages of 7th, 14th, 21st and 28th day after flowering (DAF) as wel as the root, stem, leaf at winter seedling stages of both the transgenic line W-4 and non-transgenic control Westar by real-time fluorescence quantitative PCR. [Results] The results showed the relative expression of fad2 gene was gradual y increasing with the days after flowering in the seeds of the control Westar, while it was found decreasing significantly since the 21st DAF in the seeds of the line W-4. The decline was up to 60% in comparison with the control Westar. However, no significant difference in the relative expression of fad2 gene in other organs like root, stem and leaf was observed between transgenic line W-4 and non-transgenic control Westar. Fatty acid composition analysis showed the oleic acid desaturation parameter(ODP) in seeds of the line W-4 was 0.07 in average, decreased by nearly 75% than control Westar which was 0.24 in average, while no significant difference in the seedling root, stem and leaf was measured between transgenic rapeseed and control. [Conclusion] The results above validated that RNA interference in transgenic rapeseed W-4 is at a seed-specific manner, not interfering with fad2 gene expression in organs such as the root, stem and leaf. The study also found that the period of fad2 gene expres-sion decline was wel coincided with the expression of napin gene, both appeared at the 21st DAF, indicating that the expression of dsRNA of fad2 gene is precisely control ed by the napin promoter.
文摘The experiments of primary and secondary instabilities with controlled excitation are carried out on a swept flat plate to study the process leading to the final breakdown of laminar flow. Two types of high frequency secondary instabilities are identified. The most amplified mode is centered about the inflection point of the crosswise profile of the boundary layer and is interpreted as inflectional instability, the other occurs in the one third of the boundary layer from the wall. The high frequency disturbances are highly amplified but they also saturate similarly to the primary and nonlinearly generated disturbances. Their main effect in the final breakdown seems interact with the disturbances is developed and thus widens the frequency spectrum to turbulent state.
基金Project (2011CB605500) supported by the National Basic Research Program of ChinaProject (FRF-MP-10-005B) supported by the Fundamental Research Funds for the Central Universities,China
文摘The double directional solidification(DS) technique was developed to control the lamellar microstructures in primary β TiAl-Nb alloys.Polysynthetically twinned(PST) crystals with lamellar boundaries parallel to or inclined 45o to the growth direction were achieved due to the complete peritectic transformation during directional solidification of the alloys with the dendritic solid/liquid interface.The PST crystals with aligned lamellar boundaries only parallel to the growth direction were produced when lamellar grains with lamellar boundaries in the same orientation were seeded by themselves under appropriate growth conditions.Low boron addition is harmful to align the lamellar orientation because of the growth of non-peritectic α phase.Due to the larger yttria particles and boride ribbons in the directionally solidified TiAl-Nb alloys,the tensile plastic elongations of the alloys are only close to 2%.
文摘The muhi-body analysis of the aeroelastic stability of the tiltrotor aircraft is presented. Muhi-body dynamic differential equations are combined with the equations of the unsteady dynamic inflow model to establish the complete unsteadily aeroelastic coupling analytical model of the tiltrotor. The stability of the tiltrotor in the helicopter mode is analyzed aiming at a semi span soft-inplane tihrotor model with an elastic wing. Parametric effects of the lag stiffness of blades and the flight speed are analyzed. Numerical simulations demonstrate that the multibody analytical model can analyze the aeroelastic stability of the tiltrotor aircraft in the helicopter mode.
文摘Novel 2×2 torsion-mirror optical switch arrays are fabricated by using the mixed micromachining based on the surface and bulk silicon microelectronics,then are investigated electromechanically in applied direct and alternating electric fields.When the thickness of the elastic torsion beams suspending the aluminum coated polysilicon micro-mirrors of the switches in the arrays is about 1μm,the electrostatic yielding voltages for driving the mirrors to achieve their ON-state are in the range of 270~290V,and the minimum holding voltages for mirrors ON-state are found as 55V or so.Theoretical analysis manifests that the yielding voltage is more sensitive to beam thickness than other design parameters do about the torsion-mirror switch structures.The lifetime can reach 10 8 times.The estimated shortest switching time of the switches at least lasts for less than 2ms.The force analysis on the two kinds of new fiber self-holding structures integrated monolithically in the chip of the optical switch arrays indicates that the structures can feature self-fixing and self-aligning of optical fibers.
文摘A 16 bit stereo audio novel stability fifth-order ∑△ A/D converter that consists of switched capacitor ∑△ modulators, a decimation filter, and a bandgap circuit is proposed. A method for the stabilization of a high order single stage ∑△ modulator is also proposed. A new multistage comb filter is used for the front end decimation filter. The ∑△ A/D converter achieves a peak SNR of 96dB and a dynamic range of 96dB. The ADC was implemented in 0. 5μm 5V CMOS technology. The chip die area occupies only 4. 1mm × 2.4mm and dissipates 90mW.
基金Supported by Key Project of Knowledge Innovation Project of Chinese Academy of Sciences(KGCX2-YW-374-3)Scientific and Technological Project of Shandong Province(2008GG20007002)~~
文摘[Objective] The aim was to select suitable gene for Chlorella identification and to identify the oil-producing microalgae.[Method] Four candidate gene sequences,the nuclear genomic rDNA of the 18S rRNA gene,internal transcribed spacer(ITS),internal transcribed spacer Ⅱ(ITS Ⅱ)and the chloroplast rbcL gene,were selected for Chlorella molecular identification.Through these four candidate genes,the genetic variability and distinguish ability between intra-species and inter-species was analyzed to choose the right genes for identification of the high oil-content Chlorella.On this basis,application of these gene segments were classified and identified for five fresh-water isolated Chlorella,which oil-content is more than 30%.[Result] ITS gene was a suitable gene because of its high variation and short fragment length,meanwhile its genetic distance intra-species(0.439 6±0.135 9)was larger than inter-species(0.045 7±0.084 3).Its sequence length varied between different species whereas highly conserved in the same species.By the application of ITS sequences,respectively,five high oil-content stains were identified as one C.vulgaris,two strains of C.sorokiniana and two strains of algae Chlorella sp.[Conclusion] This study had provided reference for the establishment of identification gene pool of Chlorella.