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Isolation and Manipulation of Quantitative Trait Loci for Disease Resistance in Rice Using a Candidate Gene Approach

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Molecular Plant 2008年第5期1卷 786-793页

作者： Ke-Ming Hu De-Yun Qiu xiang-ling Shen xiang-hua li Shi-Ping Wang National Key Laboratory of Crop Genetic Improvement National Center of Plant Gene Research (Wuhan) Huazhong Agricultural University Wuhan 430070 China

Bacterial blight caused by Xanthomonas oryzae pv. oryzae and fungal blast caused by Magnaporthe grisea result in heavy production losses in rice, a main staple food for approximately 50% of the world＇s population. Application of host resistance to these pathogens is the most economical and environment-friendly approach to solve this problem. Quantitative trait loci （QTLs） controlling quantitative resistance are valuable sources for broad-spectrum and durable disease resistance. Although large numbers of QTLs for bacterial blight and blast resistance have been identified, these sources have not been used effectively in rice improvement because of the complex genetic control of quantitative resistance and because the genes underlying resistance QTLs are unknown. To isolate disease resistance QTLs, we established a candidate gene strategy that integrates linkage map, expression profile, and functional complementation analyses. This strategy has proven to be applicable for identifying the genes underlying minor resistance QTLs in rice-Xoo and rice-M, grisea systems and it may also help to shed light on disease resistance QTLs of other cereals. Our results also suggest that a single minor QTL can be used in rice improvement by modulating the expression of the gene underlying the QTL. Pyramiding two or three minor QTL genes, whose expression can be managed and that function in different defense signal transduction pathways, may allow the breeding of rice cultivars that are highly resistant to bacterial blight and blast.

关键词： bacterial blight blast Oryza sativa quantitative resistance QTL.

Ortholog Alleles at Xa3/Xa26 Locus Confer Conserved Race-Specific Resistance against Xanthomonas oryzae in Rice

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Molecular Plant 2012年第1期5卷 281-290页

作者： Hong-Jing li xiang-hua li Jing-hua Xiao Rod A.Wing Shi-Ping Wang National Key Laboratory of Crop Genetic Improvement National Center of Plant Gene Research(Wuhan)Huazhong Agricultural UniversityWuhan 430070China Arizona Genomics Institute School of Plant SciencesBIO5 InstituteUniversity of ArizonaTucsonAZ 85721USA

The rice disease resistance （R） gene Xa3/Xa26 （having also been named Xa3 and Xa26） against Xanthomonas oryzae pv. oryzae （Xoo）, which causes bacterial blight disease, belongs to a multiple gene family clustered in chromosome 11 and is from an AA genome rice cultivar （Oryza sativa L.）. This family encodes leucine-rich repeat （LRR） receptor kinase- type proteins, Here, we show that the orthologs （alleles） of Xa3/Xa26, Xa3/Xa26-2, and Xa3/Xa26-3, from wild Oryza spe- cies O. officinalis （CC genome） and O. minuta （BBCC genome）, respectively, were also R genes against Xoo. Xa3/Xa26-2 and Xa3/Xa26-3 conferred resistance to 16 of the 18 Xoo strains examined. Comparative sequence analysis of the Xa3/Xa26 families in the two wild Oryza species showed that Xa3/Xa26-3 appeared to have originated from the CC genome of O. minuta. The predicted proteins encoded by Xa3/Xa26, Xa3/Xa26-2, and Xa3/Xa26-3 share 91-99% sequence identity and 94-99% sequence similarity. Transgenic plants carrying a single copy of Xa3/Xa26, Xa3/Xa26-2, or Xa3PXa26-3, in the same genetic background, showed a similar resistance spectrum to a set of Xoo strains, although plants carrying Xa3/Xa26-2 or Xa3/Xa26-3 showed lower resistance levels than the plants carrying Xa3/Xa26. These results suggest that the Xa3/Xa26 locus predates the speciation of A and C genome, which is approximately 7.5 million years ago. Thus, the resistance spec- ificity of this locus has been conserved for a long time.

关键词： Bacterial blight broad-spectrum resistance durable resistance Oryza officinalis Oryza minuta Oryza sativa.

The Year-scale X-Ray Variations in the Core of M87

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Research in Astronomy and Astrophysics 2023年第6期23卷 203-211页

作者： Yu-lin Cheng Fei xiang Heng Yu Shu-Mei Jia xiang-hua li Cheng-Kui li Yong Chen Wen-Cheng Feng Department of Astronomy Yunnan UniversityKunming 650091China Department of Astronomy Beijing Normal UniversityBeijing 100875China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjing 210023China

The analysis of light variation of M87 can help us understand the disk *** the past decade,M87 has experienced several short-term light variabilities related to *** also find that there are year-scale X-ray variations in the core of *** light variability properties are similar to *** re-analyzing 56Chandra observations from 2007 to 2019,we distinguish the“non-flaring state”from“flaring state”in the light *** removing flaring state data,we identify four gas clumps in the nucleus and all of them can be well fitted by the clumpy-ADAF *** average mass accretion rate is~0.16M⊙yr^(-1).We analyze the photon index(Γ)-flux(2-10 keV)correlation between the non-flaring state and flaring *** the non-flaring states,the flux is inversely proportional to the photon *** the flaring states,we find no obvious correlation between the two *** addition,we find that the flare always occurs at a high mass accretion rate,and after the luminosity of the flare reaches the peak,it will be accompanied by a sudden decrease in *** results can be explained as that the energy released by magnetic reconnection destroys the structure of the accretion disk,thus the luminosity decreases rapidly and returns to normal levels thereafter.

关键词： X-rays:galaxies galaxies:clusters:individual(M87) accretion accretion disks

Influence of Dog-Bone Apex on Shape During Slab Horizontal Rolling Process

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Journal of Iron and Steel Research International 2007年第3期14卷 37-41页

作者： YU Hai-liang liU xiang-hua li Chang-sheng WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

The deformation of slab with dog-bone shape during the horizontal rolling process was simulated using FEM, and the influences of apical dislocation of dog-bone on the slab spread as well as the minimum crop end loss and the lost width at slab head and tail were analyzed. The results show that with the increase in the apical dislocation of dog-bone （LA）, the slab spread and the minimum crop end loss at slab head and tail decrease, while the lost width at slab head and tail increases. Meanwhile, the relationships of S/LA-LA, LH/LA-LA, WH/LA-LA, L T/LA- LA, and W T/LA-LA were obtained.

关键词： dog-bone apical dislocation horizontal rolling FEM

OsELF3 Is Involved in Circadian Clock Regulation for Promoting Flowering under Long-Day Conditions in Rice

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Molecular Plant 2013年第1期6卷 202-215页

作者： Ying Yang Qiang Peng Guo-Xing Chen xiang-hua li Chang-Yin Wu National Key Laboratory of Crop Genetic Improvement National Center of Plant Gene Research (Wuhan) Huazhong Agricultural University Wuhan430070 China

Heading date is a critical trait that determines cropping seasons and regional adaptability in rice （Oryza sativa）. Research efforts during the last decade have identified some important photoperiod pathway genes that are conserved between Arabidopsis and rice. In this study, we identified a novel gene, Oryza sativa ELF3 （OsELF3）, which is a putative homolog of the ELF3 gene in Arabidopsis thaliana. OsELF3 was required for the control of heading date under long-day conditions. Its Tos17-tagging mutants exhibited a delayed heading date phenotype only under long-day, but not short-day, conditions. OsELF3 was highly expressed in leaf blades, and the OsELF3 protein was localized in the nucleolus. An obvious diurnal rhythm of OsELF3 transcript level was observed, with a trough in the early day and a peak in the late night in wild-type plants. However, this expression pattern was disrupted in oself3 mutants. Further inves- tigations showed that the expression of OsGI and Ghd7 was up-regulated in the oself3 mutant, indicating that OsELF3 acts as a negative regulator upstream of OsGI and Ghd7 in the flowering-time control under long-day conditions. The rhythmic expression of circadian clock-related genes, including some OsPRR members, was obviously affected in oself3 mutants. Our results indicated that OsELF3 acts as a floral activator in the long-day photoperiodic pathway via its cross- talk with the circadian clock in rice.

关键词： heading date photoperiod pathway circadian clock rice.

Influence of Edge Rolling Reduction on Plate-Edge Stress Distribution During Finish Rolling

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Journal of Iron and Steel Research International 2009年第1期16卷 22-26页

作者： YU Hai-liang liU xiang-hua CHEN li-qing li Chang-sheng ZHI Ying li Xin-wen The State Key Laboratory of Roiling and Automation Northeastern University Shenyang 110004 Liaoning China

Dimensions of one kind of stainless steel plate before finish rolling were obtained through analysis of the rough rolling processes by finite element method and updated geometrical method. The FE models of finish rolling process with a front edge roll were built, and influences of the edge rolling reduction on the stress change in the plate edge during finish rolling were analyzed. The results show that when the edge rolling reduction is increased from 0 mm to 2 mm, the compressive stress in plate corner clearly increases in edge rolling process, and the zone of tensile stress during whole rolling decreases; when the edge rolling reduction is increased from 2 mm to 5 ram, the compressive stress in the plate corner seldom changes, and the compressive stress decreases after the horizontal rolling.

关键词： edge rolling reduction stress FEM finish rolling

Grape Seed Proanthocyanidin Extract Ameliorates Streptozotocin-induced Cognitive and Synaptic Plasticity Deficits by Inhibiting Oxidative Stress and Preserving AKT and ERK Activities

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Current Medical Science 2020年第3期40卷 434-443页

作者： Wei-li GAO xiang-hua li Xin-peng DUN Xiao-kuan JING Ke YANG Yan-kun li School of Pharmacy Hubei University of Science and TechnologyXianning437100China Hubei Key Laboratory of Cardiovascular Cerebrovascular and Metabolic DisordersHubei University of Science and TechnologyXianning437100China Department of Pharmacy Huangshi Central HospitalAfiliated Hospial of Hubei Polytechnic UniversityEdong Healthcare GroupHuangshi435000China

Progressive memory loss and cognitive impairment are the main clinical manifestations of Alzheimer’s disease(AD).Currently,there is no effective drug available for the treatment of *** studies have demonstrated that the cognitive impairment of AD is associated with oxidative stress and the inhibition of AKT and ERK *** seed proanthocyanidin extract(GSPE)has been shown to have strong antioxidant effect and can protect the nervous system from oxidative stress *** study aimed to investigate the protective effect of GSPE on the cognitive and synaptic impairments of AD using a sporadic AD rat model induced by intracerebroventricular(ICV)injection of streptozotocin(STZ)(ICV-STZ).Rats were treated with GSPE(50,100,or 200 mg/kg every day)by intragastrical(ig.)administration for continuous 7 weeks,and ICV-STZ(3 mg/kg)was performed on the first day and third day of week *** and memory abilities were assessed by the Morris water maze(MWM)test at week *** behavioral test,hippocampal long-term potentiation(LTP)was recorded,and the levels of malondialdehyde(MDA),superoxide dismutases(SOD),glutathione(GSH)and the protein expression of AKT and ERK were measured in the hippocampus and cerebral cortex of *** study revealed that ICV-STZ significantly impaired the working learning ability and hippocampal LTP of rats,significantly increased the levels of MDA,and decreased the activity of SOD and GSH in the hippocampus and cerebral *** contrast,GSPE treatment prevented the impairment of cognitive function and hippocampal LTP induced by ICV-STZ,decreased the level of MDA,and increased the level of SOD and ***,Western blot results showed that GSPE treatment could prevent the loss of AKT and ERK activities in the hippocampus and cerebral cortex induced by *** findings demonstrate that GSPE treatment could ameliorate the impairment of cognitive ability and hippocampal synaptic plasticity in a rat model of sporadic AD

关键词： grape seed proanthocyanidin extract Alzheimer’s disease cognitive ability synaptic plasticity oxidative stress AKT/ERK signaling

Identification of Quantitative Trait Loci for Grain Appearance and Milling Quality Using a Doubled-Haploid Rice Population

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Journal of Integrative Plant Biology 2005年第11期47卷 1391-1403页

作者： Gong-Hao JIANG Xue-Yu HONG Cai-Guo XU xiang-hua li Yu-Qing HE State Key Laboratory of Crop Genetic Improvement and National Center of Crop Molecular Breeding Huazhong Agricultural University Wuhan 430070 China

Improving grain quality, which is composed primarily of the appearance of the grain and its cooking and milling attributes, is a major objective of many rice-producing areas in China. In the present study, we conducted a marker-based genetic analysis of the appearance and milling quality of rice （Oryza sativa L.） grains using a doubled-haploid population derived from a cross between the indica inbred Zhenshan 97 strain and the japonica inbred Wuyujing 2 strain. Quantitative trait locus （QTL） analysis using a mixed linear model approach revealed that the traits investigated were affected by one to seven QTLs that individually explained 4.0%-30.7% of the phenotypic variation. Cumulatively, the QTL for each trait explained from 12.9% to 61.4% of the phenotypic variation. Some QTLs tended to have a pleiotropic or location-linked association as a cause of the observed phenotypic correlations between different traits. Improvement of the characteristics of grain appearance and grain weight, as well as an improvement in the milling quality of rice grains, would be expected by a recombination of different QTLs using marker-assisted selection.

关键词： doubled-haploid population grain appearance quality grain milling quality Oryza sativa quantitative trait locus.

Pulsars in FIRST Observations

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Chinese Journal of Astronomy and Astrophysics 2002年第2期2卷 146-150页

作者： xiang-hua li and Jin-lin Han National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We identify 16 pulsars from the Survey of Faint Images of the Radio Sky at Twenty-cm (FIRST) at 1.4 GHz. Their positions and total flux densities are extracted from the FIRST catalog. By comparing the source positions with those in the PSR catalog, we obtain better determined positions of PSR J1022+1001, J1518+4904, J1652+2651, and proper motion upper limits of PSR J0751+1807, J1012+5307, and J1640+2224. The proper motions of the other ten pulsars are consistent with the catalog values.

关键词： pulsar: general -stars: neutron