Heading date is one of the most important agronomic traits of rice,which critically affects rice ecogeographical adaptation,yield and quality.In this study,a late heading date 3(lhd3)mutant was screened from the^(60)...Heading date is one of the most important agronomic traits of rice,which critically affects rice ecogeographical adaptation,yield and quality.In this study,a late heading date 3(lhd3)mutant was screened from the^(60)Co-γirradiation mutant library.The lhd3 delayed heading date in rice under both short day and long day conditions.Map-based cloning combined with Mutmap strategy was adopted to isolate the causal LHD3 gene.The LHD3 gene encodes a DNA_J domain protein,which was ubiquitously expressed in various plant organs,and dominant expressed in stems and leaves.Subcellular localization analysis showed that LHD3 was localized to nucleus,indicating that LHD3 may interact with other elements to regulate the expression of flowering genes.The transcriptions of the heading activators Ehd1,Hd3a and RFT1 significantly decreased in the lhd3 mutant,suggesting that LHD3 may control the heading date through the Ehd1-Hd3a/RFT1 photoperiodic flowering pathway.The variation and haplotype analyses of the genomic region of LHD3 showed that there were 7 haplotypes in the LHD3 region from 4702 accessions.The haplotypes of LHD3 can be divided into two classes:class a and class b,and the heading dates of these two classes were significantly different.Further study showed that two single nucleotide polymorphisms(SNPs),SNP10(G2100C)in Hap II and SNP3(C861T)in Hap VII,may be the functional sites causing early and late heading in accessions.Nucleotide diversity analysis showed LHD3 had been selected in the indica population,rather than in the japonica population.Therefore,the present study sheds light on the regulation of LHD3 on heading date in rice and suggests that LHD3 is a novel promising new target for rice molecular design and breeding improvement.展开更多
A long-pulse plasma discharge for more than 30 min.was achieved on the LargeHelical Device(LHD).A plasma of n_e=0.8×10^(19)m^(-3)and T_(iO)=2.0 keV was sustained withP_(ICH)=0.52 MW,P_(ECH)=0.1 MW and averaged P_...A long-pulse plasma discharge for more than 30 min.was achieved on the LargeHelical Device(LHD).A plasma of n_e=0.8×10^(19)m^(-3)and T_(iO)=2.0 keV was sustained withP_(ICH)=0.52 MW,P_(ECH)=0.1 MW and averaged P_(NBI)=0.067 MW.Total injected heatingenergy was 1.3 GJ,which was a quarter of the prepared RF heating energy.One of the keys to thesuccess of the experiment was a dispersion of the local plasma heat load to divertors,accomplishedby shifting the magnetic axis inward and outward.展开更多
The deposition profile of the impurity pellet is measured by a two-dimensional fast- framing vacuum ultraviolet （VUV） camera system in the large helical device （LHD）. The fast framing camera selectively measures t...The deposition profile of the impurity pellet is measured by a two-dimensional fast- framing vacuum ultraviolet （VUV） camera system in the large helical device （LHD）. The fast framing camera selectively measures the emission from the hydrogen-like ions of carbon （C VI） with a frame rate of several kHz. From the emission profile of the hydrogen-like carbon ions, which are in the process of ionization, the initial deposition profile of the carbon is estimated using a simple one-dimensional transport model.展开更多
In the Large Helical Device （LHD）, two different divertor configurations, i.e. helical divertor （HD） and local island divertor （LID）, are utilized to control the edge plasma. The HD with two X-points is an intri...In the Large Helical Device （LHD）, two different divertor configurations, i.e. helical divertor （HD） and local island divertor （LID）, are utilized to control the edge plasma. The HD with two X-points is an intrinsic divertor for heliotron devices, accompanied with a relatively thick ergodic layer outside the confinement region. Edge and divertor plasma behavior from low density to high density regimes is presented, referring to the divertor detachment. The effect of the ergodic layer on the edge transport is also discussed. On the other hand, the LID is an advanced divertor concept which realizes a high pumping efficiency by the combination of an externally induced magnetic island and a closed pumping system. Experimental results to confirm the fundamental divertor performance of the LID are presented.展开更多
In large helical device （LHD）, antenna loadings are different for minority ion cyclotron heating （MICH with 38.47 MHz） and mode-converted ion Bernstein wave heating （MC-IBW with 28.4 MHz）, and it is necessary to...In large helical device （LHD）, antenna loadings are different for minority ion cyclotron heating （MICH with 38.47 MHz） and mode-converted ion Bernstein wave heating （MC-IBW with 28.4 MHz）, and it is necessary to improve antenna loading with low heating efficiency to avoid arching on transmission line. To design a new ion cyclotron range of frequencies （ICRF） antenna in LHD, calculation for a simple antenna model is conducted using three-dimensional electrical magnetic code （high frequency structure simulator, HFSS） for an water loading as an imaginary plasma with low heating efficiency. At resonant frequencies, antenna loading is sensitive to strap width, and resonant frequencies are strongly related to strap height. There is no differences of RF current profile on the strap surface between resonant frequency and non-resonant frequency. The strap should be perpendicularly placed against the magnetic field line, since Faraday-shield angle will lead to a decrease in the effective antenna height.展开更多
Two pairs of high-frequency magnetic probes were installed in the Large Helical Device （LHD）. During the injection of a perpendicular neutral beam, ion cyclotron emissions （ICEs） with the fundamental frequency cor...Two pairs of high-frequency magnetic probes were installed in the Large Helical Device （LHD）. During the injection of a perpendicular neutral beam, ion cyclotron emissions （ICEs） with the fundamental frequency corresponding to the ion cyclotron frequency at the plasma edge were detected, which are the same type of ICE as measured with the former spare ion cyclotron range of frequencies （ICRF） heating antennas. This type of ICE was further investigated with regard to the phase and intensity of signals. Another type of ICE was found in the LHD, and these ICEs were synchronized with bursts of toroidicity induced Alfv^n eigenmodes （TAE） and the rise of intensity of lost ion flux. Therefore the source of these ICEs was thought to be the particles transferred from the core to the outer region of plasma by the TAE bursts. The frequency of ICEs induced by the TAE bursts increases linearly with the magnetic field strength, since the ion cyclotron frequency increases with the magnetic field strength.展开更多
The Editor welcomes submissions for possible publication in the Letters to the Editor section that consist of commentary on an article published in the Journal or other relevant issues.
To realize an excitation of electron Bernstein waves （EBW） via mode conversion from X-mode waves injected from the high magnetic field side （HFS）, new inner-vessel mirrors were installed close to a helicM coil in ...To realize an excitation of electron Bernstein waves （EBW） via mode conversion from X-mode waves injected from the high magnetic field side （HFS）, new inner-vessel mirrors were installed close to a helicM coil in the large helicM device （LHD）. 77 GHz electron cyclotron （EC） wave beams injected from an existing EC-wave injection system toward the new mirror are reflected on the mirror so that the beams are injected to plasmas from HFS. Evident increases in the electron temperature at the plasma core region and the plasma stored energy were observed by the HFS beam injection to the plasmas with the line-average electron density of 7.5~ 1019 m-3, which is slightly higher than the plasma cut-off density of 77 GHz EC-waves, 7.35~ 1019 m-3. The heating efficiency evaluated from the changes in the time derivative of the plasma stored energy reached ,,~70%. Although so far it is not clear which is the main cause of the heating effect, the mode-converted EBW or the X-mode wave itself injected from the HFS, an effective heating of high-density plasma over the plasma cut-off of EC-wave was successfully demonstrated.展开更多
Shown is a possibility to make the image of a laser beam over a distance of 2.5 m, formed by the spherical multi-segment mirror installed in LHD, twice sharper by suitably adjusting the inclination of each segment mir...Shown is a possibility to make the image of a laser beam over a distance of 2.5 m, formed by the spherical multi-segment mirror installed in LHD, twice sharper by suitably adjusting the inclination of each segment mirror, which is equivalent to making the mirror surface aspherical. This will further enhance the attractiveness of a mirror-based Thomson scattering system.展开更多
基金funded by the National Basic Research Program of China(Grant No.2016YFD0100401)National Natural Science Foundation of China(Grant No.31571742)Scientific Research Initiation Fund of Zhejiang University of Science and Technology,China(Grant No.19042142-Y)。
文摘Heading date is one of the most important agronomic traits of rice,which critically affects rice ecogeographical adaptation,yield and quality.In this study,a late heading date 3(lhd3)mutant was screened from the^(60)Co-γirradiation mutant library.The lhd3 delayed heading date in rice under both short day and long day conditions.Map-based cloning combined with Mutmap strategy was adopted to isolate the causal LHD3 gene.The LHD3 gene encodes a DNA_J domain protein,which was ubiquitously expressed in various plant organs,and dominant expressed in stems and leaves.Subcellular localization analysis showed that LHD3 was localized to nucleus,indicating that LHD3 may interact with other elements to regulate the expression of flowering genes.The transcriptions of the heading activators Ehd1,Hd3a and RFT1 significantly decreased in the lhd3 mutant,suggesting that LHD3 may control the heading date through the Ehd1-Hd3a/RFT1 photoperiodic flowering pathway.The variation and haplotype analyses of the genomic region of LHD3 showed that there were 7 haplotypes in the LHD3 region from 4702 accessions.The haplotypes of LHD3 can be divided into two classes:class a and class b,and the heading dates of these two classes were significantly different.Further study showed that two single nucleotide polymorphisms(SNPs),SNP10(G2100C)in Hap II and SNP3(C861T)in Hap VII,may be the functional sites causing early and late heading in accessions.Nucleotide diversity analysis showed LHD3 had been selected in the indica population,rather than in the japonica population.Therefore,the present study sheds light on the regulation of LHD3 on heading date in rice and suggests that LHD3 is a novel promising new target for rice molecular design and breeding improvement.
基金supported in part by the JSPS-CAS Core-University Program in the field of Plasma and Nuclear Fusion
文摘A long-pulse plasma discharge for more than 30 min.was achieved on the LargeHelical Device(LHD).A plasma of n_e=0.8×10^(19)m^(-3)and T_(iO)=2.0 keV was sustained withP_(ICH)=0.52 MW,P_(ECH)=0.1 MW and averaged P_(NBI)=0.067 MW.Total injected heatingenergy was 1.3 GJ,which was a quarter of the prepared RF heating energy.One of the keys to thesuccess of the experiment was a dispersion of the local plasma heat load to divertors,accomplishedby shifting the magnetic axis inward and outward.
基金supported by the NIFS budget code ULPP021,the Ministry of Education Science,Sports and CultureGrant-in-Aid for Scientific Research(B)23340184partially supported by the JSPS-NRF-NSFC A3 Foresight Program in the field of Plasma Physics(No.11261140328)
文摘The deposition profile of the impurity pellet is measured by a two-dimensional fast- framing vacuum ultraviolet （VUV） camera system in the large helical device （LHD）. The fast framing camera selectively measures the emission from the hydrogen-like ions of carbon （C VI） with a frame rate of several kHz. From the emission profile of the hydrogen-like carbon ions, which are in the process of ionization, the initial deposition profile of the carbon is estimated using a simple one-dimensional transport model.
基金supported by NIFS under Grant(No.NIFS05ULPP506)in part by the JSPS-CAS Core-University Program in the field of Plasma and Nuclear Fusion
文摘In the Large Helical Device （LHD）, two different divertor configurations, i.e. helical divertor （HD） and local island divertor （LID）, are utilized to control the edge plasma. The HD with two X-points is an intrinsic divertor for heliotron devices, accompanied with a relatively thick ergodic layer outside the confinement region. Edge and divertor plasma behavior from low density to high density regimes is presented, referring to the divertor detachment. The effect of the ergodic layer on the edge transport is also discussed. On the other hand, the LID is an advanced divertor concept which realizes a high pumping efficiency by the combination of an externally induced magnetic island and a closed pumping system. Experimental results to confirm the fundamental divertor performance of the LID are presented.
基金supported partially by the JSPS-CAS Core-University program in the field of 'Plasma and Nuclear Fusion'
文摘In large helical device （LHD）, antenna loadings are different for minority ion cyclotron heating （MICH with 38.47 MHz） and mode-converted ion Bernstein wave heating （MC-IBW with 28.4 MHz）, and it is necessary to improve antenna loading with low heating efficiency to avoid arching on transmission line. To design a new ion cyclotron range of frequencies （ICRF） antenna in LHD, calculation for a simple antenna model is conducted using three-dimensional electrical magnetic code （high frequency structure simulator, HFSS） for an water loading as an imaginary plasma with low heating efficiency. At resonant frequencies, antenna loading is sensitive to strap width, and resonant frequencies are strongly related to strap height. There is no differences of RF current profile on the strap surface between resonant frequency and non-resonant frequency. The strap should be perpendicularly placed against the magnetic field line, since Faraday-shield angle will lead to a decrease in the effective antenna height.
基金supported by NIFS budgets NIFS10ULRR003,NIFS11ULRR703,and NIFS11PLRR302
文摘Two pairs of high-frequency magnetic probes were installed in the Large Helical Device （LHD）. During the injection of a perpendicular neutral beam, ion cyclotron emissions （ICEs） with the fundamental frequency corresponding to the ion cyclotron frequency at the plasma edge were detected, which are the same type of ICE as measured with the former spare ion cyclotron range of frequencies （ICRF） heating antennas. This type of ICE was further investigated with regard to the phase and intensity of signals. Another type of ICE was found in the LHD, and these ICEs were synchronized with bursts of toroidicity induced Alfv^n eigenmodes （TAE） and the rise of intensity of lost ion flux. Therefore the source of these ICEs was thought to be the particles transferred from the core to the outer region of plasma by the TAE bursts. The frequency of ICEs induced by the TAE bursts increases linearly with the magnetic field strength, since the ion cyclotron frequency increases with the magnetic field strength.
文摘The Editor welcomes submissions for possible publication in the Letters to the Editor section that consist of commentary on an article published in the Journal or other relevant issues.
基金supported by KAKENHI (Grant-in-Aid for Scientific Research(C), 21560862) of Japan
文摘To realize an excitation of electron Bernstein waves （EBW） via mode conversion from X-mode waves injected from the high magnetic field side （HFS）, new inner-vessel mirrors were installed close to a helicM coil in the large helicM device （LHD）. 77 GHz electron cyclotron （EC） wave beams injected from an existing EC-wave injection system toward the new mirror are reflected on the mirror so that the beams are injected to plasmas from HFS. Evident increases in the electron temperature at the plasma core region and the plasma stored energy were observed by the HFS beam injection to the plasmas with the line-average electron density of 7.5~ 1019 m-3, which is slightly higher than the plasma cut-off density of 77 GHz EC-waves, 7.35~ 1019 m-3. The heating efficiency evaluated from the changes in the time derivative of the plasma stored energy reached ,,~70%. Although so far it is not clear which is the main cause of the heating effect, the mode-converted EBW or the X-mode wave itself injected from the HFS, an effective heating of high-density plasma over the plasma cut-off of EC-wave was successfully demonstrated.
基金supported by the LHD project(NIFS09ULHH502)by the JSPS-CAS Core-University program in the field of 'Plasma and Nuclear Fusion'
文摘Shown is a possibility to make the image of a laser beam over a distance of 2.5 m, formed by the spherical multi-segment mirror installed in LHD, twice sharper by suitably adjusting the inclination of each segment mirror, which is equivalent to making the mirror surface aspherical. This will further enhance the attractiveness of a mirror-based Thomson scattering system.
