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Soybean GmMYB76, GmMYB92, and GmMYB177 genes confer stress tolerance in transgenic Arabidopsis plants 被引量:74
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作者 Yong Liao Hong-Feng Zou Hui-Wen Wang Wan-Ke Zhang biao Ma jin-Song Zhang Shou-Yi Chen 《Cell Research》 SCIE CAS CSCD 2008年第10期1047-1060,共14页
MYB-type transcription factors contain the conserved MYB DNA-binding domain of approximately 50 amino acids and are involved in the regulation of many aspects of plant growth, development, metabolism and stress respon... MYB-type transcription factors contain the conserved MYB DNA-binding domain of approximately 50 amino acids and are involved in the regulation of many aspects of plant growth, development, metabolism and stress responses. From soybean plants, we identified 156 GmMYB genes using our previously obtained 206 MYB unigenes, and 48 were found to have full-length open-reading frames. Expressions of all these identified genes were examined, and we found that expressions of 43 genes were changed upon treatment with ABA, salt, drought and/or cold stress. Three GmMYB genes, GmMYB76, GmMYB92 and GmMYB177, were chosen for further analysis. Using the yeast assay system, GmMYB76 and GmMYB92 were found to have transactivation activity and can form homodimers. GmMYB177 did not appear to have transactivation activity but can form heterodimers with GmMYB76. Yeast onehybrid assay revealed that all the three GmMYBs could bind to cis-elements TAT AAC GGT TTT TT and CCG GAA AAA AGG AT, but with different affinity, and GmMYB92 could also bind to TCT CAC CTA CC. The transgenic Arabidopsis plants overexpressing GmMYB 76 or GmMYB177 showed better performance than the GmMYB92-transgenic plants in salt and freezing tolerance. However, these transgenic plants exhibited reduced sensitivity to ABA treatment at germination stage in comparison with the wild-type plants. The three GmMYB genes differentially affected a subset of stress-responsive genes in addition to their regulation of a common subset of stress-responsive genes. These resuits indicate that the three GmMYB genes may play differential roles in stress tolerance, possibly through regulation of stress-responsive genes. 展开更多
关键词 SOYBEAN MYB transcription factor abiotic stress tolerance
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Broadband diffusion of terahertz waves by multi-bit coding metasurfaces 被引量:38
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作者 Li-Hua Gao Qiang Cheng +15 位作者 jing Yang Shao-Jie Ma Jie Zhao Shuo Liu Hai-Bing Chen Qiong He Wei-Xiang Jiang Hui-Feng Ma Qi-Ye Wen Lan-Ju Liang biao-Bing jin Wei-Wei Liu Lei Zhou Jian-Quan Yao Pei-Heng Wu Tie-Jun Cui 《Light(Science & Applications)》 SCIE EI CAS CSCD 2015年第1期207-215,共9页
The terahertz region is a special region of the electromagnetic spectrum that incorporates the advantages of both microwaves and infrared light waves.In the past decade,metamaterials with effective medium parameters o... The terahertz region is a special region of the electromagnetic spectrum that incorporates the advantages of both microwaves and infrared light waves.In the past decade,metamaterials with effective medium parameters or gradient phases have been studied to control terahertz waves and realize functional devices.Here,we present a new approach to manipulate terahertz waves by using coding metasurfaces that are composed of digital coding elements.We propose a general coding unit based on a Minkowski closed-loop particle that is capable of generating 1-bit coding(with two phase states of 0 and 180°),2-bit coding(with four phase states of 0,90°,180°,and 270°),and multi-bit coding elements in the terahertz frequencies by using different geometric scales.We show that multi-bit coding metasurfaces have strong abilities to control terahertz waves by designing-specific coding sequences.As an application,we demonstrate a new scattering strategy of terahertz waves—broadband and wide-angle diffusion—using a 2-bit coding metasurface with a special coding design and verify it by both numerical simulations and experiments.The presented method opens a new route to reducing the scattering of terahertz waves. 展开更多
关键词 CODING DIFFUSION metasurface terahertz waves
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Cytological, physiological, and transcriptomic analyses of golden leaf coloration in Ginkgo biloba L 被引量:37
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作者 Wei-xing Li Shun-bo Yang +5 位作者 Zhaogeng Lu Zhi-chong He Yun-ling Ye Bei-bei Zhao Li Wang biao jin 《Horticulture Research》 SCIE 2018年第1期797-810,共14页
Ginkgo biloba is grown worldwide as an ornamental plant for its golden leaf color.However,the regulatory mechanism of leaf coloration in G.biloba remains unclear.Here,we compared G.biloba gold-colored mutant leaves an... Ginkgo biloba is grown worldwide as an ornamental plant for its golden leaf color.However,the regulatory mechanism of leaf coloration in G.biloba remains unclear.Here,we compared G.biloba gold-colored mutant leaves and normal green leaves in cytological,physiological and transcriptomic terms.We found that chloroplasts of the mutant were fewer and smaller,and exhibited ruptured thylakoid membranes,indistinct stromal lamellae and irregularly arranged vesicles.Physiological experiments also showed that the mutant had a lower chlorophyll,lower flavonoid and higher carotenoid contents(especially lutein).We further used transcriptomic sequencing to identify 116 differentially expressed genes(DEGs)and 46 transcription factors(TFs)involved in chloroplast development,chlorophyll metabolism,pigment biosynthesis and photosynthesis.Among these,the chlorophyll biosynthesis-related PPO showed down-regulation,while chlorophyll degradation-related NYC/NOL had up-regulated expression in mutant leaves.Z-ISO,ZDS,and LCYE,which are involved in carotenoid biosynthesis were up-regulated.Quantitative real-time PCR(RT-qPCR)further confirmed the altered expression levels of these genes at three stages.The alteration of PPO and NYC/NOL gene expression might affect chlorophyll biosynthesis and promote degradation of chlorophyll b to chlorophyll a,while the up-regulated genes Z-ISO,ZDS and LCYE enhanced carotenoid accumulation.Consequently,changes in the ratio of carotenoids to chlorophylls were the main factors driving the golden leaf coloration in the mutant G.biloba. 展开更多
关键词 METABOLISM GOLDEN FIR
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Photodynamic therapy of condyloma acuminata in pregnant women 被引量:28
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作者 YANG Yu-guang ZOU Xian-biao +2 位作者 ZHAO Hua ZHANG Yun-jie LI Heng-jin 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第16期2925-2928,共4页
Background Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an emerging technique for the treatment of genital human papillomavirus (HPV)-induced benign and premalignant lesions. We report here in ... Background Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an emerging technique for the treatment of genital human papillomavirus (HPV)-induced benign and premalignant lesions. We report here in a case series of condyloma acuminata (CA) in pregnancy successfully treated with ALA-PDT. Methods Five pregnant patients with CA received three to four times treatment respectively. Patients were followed up for 6-23 months after treatment. Results The clearance rate of genital warts was 100%. No recurrence was found during the follow-up period. Major adverse events reported were mild erosion, pain, and local edema. All pregnancies resulted in healthy live births without delivery complications. Conclusions PDT with topical ALA seems to be safe and effective in the treatment of CA in pregnancy. It demonstrated high clearance rate of warts, was well-tolerated by patients, and showed no adverse effects on mothers or fetuses. ALA-PDT may be an ideal strategy of treatment for pregnant women with CA. 展开更多
关键词 Condyloma acuminatum pregnancy aminolevulinic acid photodynamic therapy
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Ethylene Signaling in Rice and Arabidopsis: Conserved and Diverged Aspects 被引量:26
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作者 Chao Yang Xiang Lu biao Ma Shou-Yi Chen jin-Song Zhang 《Molecular Plant》 SCIE CAS CSCD 2015年第4期495-505,共11页
Ethylene as a gas phytohormone plays significant roles in the whole life cycle of plants, ranging from growth and development to stress responses. A linear ethylene signaling pathway has been established in the dicoty... Ethylene as a gas phytohormone plays significant roles in the whole life cycle of plants, ranging from growth and development to stress responses. A linear ethylene signaling pathway has been established in the dicotyledonous model plant Arabidopsis. However, the ethylene signaling mechanism in monocotyledonous plants such as rice is largely unclear. In this review, We compare the ethylene response phenotypes of dark-grown seedlings of Arabidopsis, rice, and other monocotyledonous plants (maize, wheat, sorghum, and Brachypodium distachyon) and pinpoint that rice has a distinct phenotype of root inhibition but coleoptile promotion in etiolated seedlings upon ethylene treatment. We further summarize the homologous genes of Arabidopsis ethylene signaling components in these monocotyledonous plants and discuss recent progress. Although conserved in most aspects, ethylene signaling in rice has evolved new features compared with that in Arabidopsis. These analyses provide novel insights into the understanding of ethylene signaling in the dicotyledonous Arabidopsis and monocotyledonous plants, particularly rice. Further characterization of rice ethylene-responsive mutants and their corresponding genes will help us better understand the whole picture of ethylene signaling mechanisms in plants. 展开更多
关键词 ethylene response SIGNALING ARABIDOPSIS RICE monocotyledonous plants CROSSTALK
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牛至、香茅、丁香精油化学成分及体外抑菌活性研究 被引量:25
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作者 牛彪 金川 +5 位作者 梁剑平 尚若锋 郝宝成 王学红 杨珍 刘宇 《食品研究与开发》 CAS 北大核心 2020年第3期46-52,共7页
采用滤纸片法、肉汤稀释法和点种法研究3种植物精油及其化学成分对5种病原菌的体外抑菌活性。用气相色谱-质谱联用技术(gas chromatography-mass spectrometer,GC-MS)最佳分析条件对化学活性成分进行鉴定,用峰面积归一法测定各化合物在... 采用滤纸片法、肉汤稀释法和点种法研究3种植物精油及其化学成分对5种病原菌的体外抑菌活性。用气相色谱-质谱联用技术(gas chromatography-mass spectrometer,GC-MS)最佳分析条件对化学活性成分进行鉴定,用峰面积归一法测定各化合物在挥发油中的相对百分含量。结果表明:9.5%的牛至、香茅、丁香精油可将白色葡萄球菌、白色念珠菌全部杀灭;4.75%的牛至、香茅、丁香精油可将金黄色葡萄球菌全部杀灭;4.75%牛至、丁香精油可将大肠埃希菌全部杀灭,但香茅精油杀灭浓度相对较弱;3种精油对铜绿假单胞菌的杀灭浓度均大于9.5%;GC-MS结果显示,牛至精油中主要含有双戊烯(33.93%)、百里香酚(19.12%)、4-萜品醇(14.92%)、α-蒎烯(10.87%);丁香精油主要成分为丁香酚(86.54%),1-石竹烯(10.41%);香茅精油主要包括香茅醛(31.38%)、香叶醇(18.43%);植物精油具有广谱的抑菌活性。 展开更多
关键词 植物精油 化学成分 滤纸片法 肉汤稀释法 气相色谱-质谱连用技术
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A PP2C-1 Allele Underlying a Quantitative Trait Locus Enhances Soybean l O0-Seed Weight 被引量:23
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作者 Xiang Lu Qing Xiong +11 位作者 Tong Cheng Qing-Tian Li Xin-Lei Liu Ying-Dong Bi Wei Li Wan-Ke Zhang biao Ma Yong-Cai Lai Wei-Guang Du Wei-Qun Man Shou-Yi Chen jin-Song Zhang 《Molecular Plant》 SCIE CAS CSCD 2017年第5期670-684,共15页
Cultivated soybeans may lose some useful genetic loci during domestication. Introgression of genes from wild soybeans could broaden the genetic background and improve soybean agronomic traits. In this study, through w... Cultivated soybeans may lose some useful genetic loci during domestication. Introgression of genes from wild soybeans could broaden the genetic background and improve soybean agronomic traits. In this study, through whole-genome sequencing of a recombinant inbred line population derived from a cross between a wild soybean ZYD7 and a cultivated soybean HN44, and mapping of quantitative trait loci for seed weight, we discovered that a phosphatase 2C-1 (PP2C-1) allele from wild soybean ZYD7 contributes to the increase in seed weight/size. PP2C-1 may achieve this function by enhancing cell size of integument and activating a subset of seed trait-related genes. We found that PP2C-1 is associ- ated with GmBZR1, a soybean ortholog of Arabidopsis BZR1, one of key transcription factors in brassi- nosteroid (BR) signaling, and facilitate accumulation of dephosphorylated GmBZR1. In contrast, the PP2C-2 allele with variations of a few amino acids at the N-terminus did not exhibit this function. More- over, we showed that GmBZR1 could promote seed weight/size in transgenic plants. Through analysis of cultivated soybean accessions, we found that 40% of the examined accessions do not have the PP2C-1 allele, suggesting that these accessions can be improved by introduction of this allele. Taken together, our study identifies an elite allele PP2C-1, which can enhance seed weight and/or size in soybean, and pinpoints that manipulation of this allele by molecular-assisted breeding may increase production in soybean and other legumes/crops. 展开更多
关键词 SOYBEAN lO0-seed weight PP2C-1 BZR1
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Therapeutic potential of Gastrodia elata Blume for the treatment of Alzheimer's disease 被引量:22
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作者 Guang-biao Huang Tong Zhao +10 位作者 Sushma Shrestha Muna Hong-Mei jin Jong-Il Park Kyu-Sik Jo Bo-Hee Lee Soo-Wan Chae Sun-Young Kim Soo-Hyun Park Eun-Ock Park Eun-Kyung Choi Young-Chul Chung 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第12期1061-1070,共10页
Several studies have demonstrated that the Chinese herb Gastrodia elata Blume can protect against amyloid beta-peptide (Ap)-induced cell death. To investigate the possible therapeutic effects of Gastrodia elata Blum... Several studies have demonstrated that the Chinese herb Gastrodia elata Blume can protect against amyloid beta-peptide (Ap)-induced cell death. To investigate the possible therapeutic effects of Gastrodia elata Blume on Alzheimer's disease, we established a rat model of AIzheimer's disease by injecting A325-35 into bilateral hippocampi. These rats were intragastrically administered 500 or 1 000 mg/kg Gastrodia elata Blume per day for 52 consecutive days. Morris water maze tests showed that Gastrodia elata Blume treatment significantly improved the spatial memory of Alzheimer's disease rats. Congo red staining revealed that Gastrodia elata Blume significantly reduced the number of amyloid deposits in the hippocampus of these rats. Western blot analysis showed that choline acetyltransferase expression in the medial septum and hippocampus was significantly increased by the treatment of Gastrodia elata Blume, while EIIman method showed significant decrease in the activity of acetylcholinesterase in all three regions (prefrontal cortex, medial septum and hippocampus). These findings suggest that long-term administration of Gastrodia elata Blume has therapeutic potential for Alzheimer's disease. 展开更多
关键词 neural regeneration neuroprotective effect Traditional Chinese medicine Gastrodia elata Blume Alzheimer's disease Morris water maze test choline acetyltransferase ACETYLCHOLINESTERASE grants-supported paper NEUROREGENERATION
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Measurement of Local Gravity via a Cold Atom Interferometer 被引量:22
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作者 ZHOU Lin 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第1期78-81,共4页
We demonstrate a precision measurement of local gravity acceleration 9 in Wuhan by a compact cold atom interferometer. The atom interferometer is in vertical Mach-Zehnder configuration realized using a 7r /2 - π - π... We demonstrate a precision measurement of local gravity acceleration 9 in Wuhan by a compact cold atom interferometer. The atom interferometer is in vertical Mach-Zehnder configuration realized using a 7r /2 - π - π /2 Raman pulse sequence. Cold atoms were prepared in a magneto-optical trap, launched upward to form an atom fountain, and then coherently manipulated to interfere by stimulated Raman transition. Population signal vs Raman laser phase was recorded as interference fringes, and the local gravity was deduced from the interference signal. We have obtained a resolution of 7 × 10-9g after an integration time of 236s under the best vibrational environment conditions. The absolute g value was derived from the chirp rate with a difference of 1.5 × 10--07 g compared to the gravity reference value. The tidal phenomenon was observed by continuously monitoring the local gravity over 123 h. 展开更多
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Identification of Rice Ethylene-Response Mutants and Characterization of MHZ71OsEIN2 in Distinct Ethylene Response and Yield Trait Regulation 被引量:20
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作者 biao Ma Si-Jie He +11 位作者 Kai-Xuan Duan Cui-Cui Yin Hui Chen Chao Yang Qing Xiong Qing-Xin Song Xiang LU Hao-Wei Chen dVan-Ke Zhang Tie-Gang Lu Shou-Yi Chen jin-Song Zhang 《Molecular Plant》 SCIE CAS CSCD 2013年第6期1830-1848,共19页
Ethylene plays essential roles in adaptive growth of rice plants in water-saturating environment; how- ever, ethylene signaling pathway in rice is largely unclear. In this study, we report identification and character... Ethylene plays essential roles in adaptive growth of rice plants in water-saturating environment; how- ever, ethylene signaling pathway in rice is largely unclear. In this study, we report identification and characterization of ethylene-response mutants based on the specific ethylene-response phenotypes of etiolated rice seedlings, includ- ing ethylene-inhibited root growth and ethylene-promoted coleoptile elongation, which is different from the ethylene triple-response phenotype in Arabidopsis. We establish an efficient system for screening and a set of rice mutants have been identified. Genetic analysis reveals that these mutants form eight complementation groups. All the mutants show insensitivity or reduced sensitivity to ethylene in root growth but exhibit differential responses in cole0ptile growth. One mutant group mhz7 has insensitivity to ethylene in both root and coleoptile growth. We identified the corresponding gene by a map-based cloning method. MHZ7 encodes a membrane protein homologous to EIN2, a central component of ethylene signaling in Arabidopsis. Upon ethylene treatment, etiolated MHZ7-overexpressing seedlings exhibit enhanced coleoptiie elongation, increased mesocotyl growth and extremely twisted short roots, featuring enhanced ethylene- response phenotypes in rice. Grain length was promoted in MHZ7-transgenic plants and 1000-grain weight was reduced in mhz7 mutants. Leaf senescent process was also affected by MHZ7 expression. Manipulation of ethylene signaling may improve adaptive growth and yield-related traits in rice. 展开更多
关键词 RICE ethylene-response mutant MHZ7 yield traits senescence.
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Application of 3D reconstruction for surgical treatment of hepatic alveolar echinococcosis 被引量:17
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作者 Yi-biao He Lei Bai +6 位作者 Tuerganaili Aji Yi Jiang jin-Ming Zhao jin-Hui Zhang Ying-Mei Shao Wen-Ya Liu Hao Wen 《World Journal of Gastroenterology》 SCIE CAS 2015年第35期10200-10207,共8页
AIM: To evaluate the reliability and accuracy of threedimensional(3D) reconstruction for liver resection in patients with hepatic alveolar echinococcosis(HAE).METHODS: One-hundred and six consecutive patients with HAE... AIM: To evaluate the reliability and accuracy of threedimensional(3D) reconstruction for liver resection in patients with hepatic alveolar echinococcosis(HAE).METHODS: One-hundred and six consecutive patients with HAE underwent hepatectomy at our hospital between May 2011 and January 2015. Fifty-nine patients underwent preoperative 3D reconstruction and "virtual" 3D liver resection before surgery(Group A). Another 47 patients used conventional imaging methods for preoperative assessment(Group B). Outcomes of hepatectomy were compared between the two groups.RESULTS: There was no significant difference in preoperative data between the two groups. Compared with patients in Group B, those in Group A had a significantly shorter operation time(227.1 ± 51.4 vs 304.6 ± 88.1 min; P < 0.05), less intraoperative blood loss(308.1 ± 135.4 vs 458.1 ± 175.4 m L; P < 0.05), and lower requirement for intraoperative blood transfusion(186.4 ± 169.6 vs 289.4 ± 199.2 m L; P < 0.05). Estimated resection liver volumes in bothgroups had good correlation with actual graft weight(Group A: r = 0.978; Group B: r = 0.960). There was a significant higher serum level of albumin in Group A(26.3 ± 5.9 vs 22.6 ± 4.3 g/L, P < 0.05). Other postoperative laboratory parameters(serum levels of aminotransferase and bilirubin; prothrombin time) and duration of postoperative hospital stay were similar. Sixteen complications occurred in Group A and 19 in Group B. All patients were followed for 3-46(mean, 17.3) mo. There was no recurrence of lesions in Group A, but two recurrences in Group B. There were three deaths: two from cerebrovascular accident, and one from car accident.CONCLUSION: 3D reconstruction provides comprehensive and precise anatomical information for the liver. It also improves the chance of success and reduces the risk of hepatectomy in HAE. 展开更多
关键词 LIVER RESECTION HEPATIC ALVEOLAR ECHINOCOCCOSIS CO
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An R2R3-type transcription factor gene AtMYB59 regulates root growth and cell cycle progression in Arabidopsis 被引量:18
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作者 Rui-Ling Mu Yang-Rong Cao +10 位作者 Yun-Feng Liu Gang Lei Hong-Feng Zou Yong Liao Hui-Wen Wang Wan-Ke Zhang biao Ma Ji-Zhou Du Ming Yuan jin-Song Zhang Shou-Yi Chen 《Cell Research》 SCIE CAS CSCD 2009年第11期1291-1304,共14页
MYB proteins play important roles in eukaryotic organisms. In plants, the R1R2R3-type MYB proteins function in cell cycle control. However, whether the R2R3-type MYB protein is also involved in the cell division proce... MYB proteins play important roles in eukaryotic organisms. In plants, the R1R2R3-type MYB proteins function in cell cycle control. However, whether the R2R3-type MYB protein is also involved in the cell division process remains unknown. Here, we report that an R2R3-type transcription factor gene, AtMYB59, is involved in the regulation of cell cycle progression and root growth. The AtMYB59 protein is localized in the nuclei of onion epidermal cells and has transactivation activity. Expression of AtMYB59 in yeast cells suppresses cell proliferation, and the transfor- mants have more nuclei and higher anenpioid DNA content with longer cells. Mutation in the conserved domain of AtMYB59 abolishes its effects on yeast cell growth. In synchronized Arabidopsis cell suspensions, the AtMYB59 gene is specifically expressed in the S phase during cell cycle progression. Expression and promoter-GUS analysis reveals that the AtMYB59 gene is abundantly expressed in roots. Transgenic plants overexpressing AtMYB59 have shorter roots compared with wild-type plants (Arabidopsis accession Col-0), and around half of the mitotic cells in root tips are at metaphase. Conversely, the null mutant myb59-1 has longer roots and fewer mitotic cells at metaphase than Col, suggesting that AtMYB59 may inhibit root growth by extending the metaphase of mitotic cells. AtMYB59 regulates many downstream genes, including the CYCB1;1 gene, probably through binding to MYB-responsive elements. These results support a role forAtMYB59 in cell cycle regulation and plant root growth. 展开更多
关键词 MYB protein transcription factor cell cycle root growth
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基于BP人工神经网络算法的苹果制干适宜性评价 被引量:18
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作者 张彪 刘璇 +4 位作者 毕金峰 吴昕烨 金鑫 李旋 李潇 《中国农业科学》 CAS CSCD 北大核心 2019年第1期129-142,共14页
目的】建立苹果原料制干适宜性评价模型,实现基于苹果原料指标预测干制品品质的目标,为苹果制干专用化原料的筛选提供方法依据,为明确苹果干制品品质形成的基础物质提供数据支持。【方法】以来自7个不同主产区的21个主栽品种,共34份苹... 目的】建立苹果原料制干适宜性评价模型,实现基于苹果原料指标预测干制品品质的目标,为苹果制干专用化原料的筛选提供方法依据,为明确苹果干制品品质形成的基础物质提供数据支持。【方法】以来自7个不同主产区的21个主栽品种,共34份苹果鲜果样本为研究对象,运用多种数据处理方法建立苹果脆片品质综合评价模型与苹果原料制干适宜性评价模型。(1)利用压差闪蒸干燥方法制备34份苹果鲜果的脆片样本,测定苹果脆片17项品质指标,采用因子分析进行降维并筛选得到苹果脆片品质评价核心指标,运用层次分析法得到脆片核心指标权重值,构建脆片品质综合评价模型并计算得到脆片综合评价得分。(2)测定34份苹果鲜果样本22项品质指标,与脆片核心指标进行相关性分析并筛选出与脆片品质相关的果实特征指标。选用29个样本以果实特征指标为输入,对应脆片综合评价得分为输出,利用误差反向传播(Error Back Propagation,BP)神经网络算法构建学习模型;其余5个样本为验证样本,评价学习模型的预测准确性。变换3组学习样本构建3个学习模型,对比3个模型的预测准确性,验证建模方法的合理性与稳定性。【结果】苹果脆片L*值、脆度、膨化度、可滴定酸含量、可溶性糖含量和粗蛋白含量被确定为不同样本脆片品质综合评价的核心指标,构建的苹果脆片品质综合评价模型为Y_(综合得分)=L*值×0.3724+脆度×0.2665+膨化度×0.1583+可滴定酸含量×0.0890+可溶性糖含量×0.0569+粗蛋白含量×0.0569。34个苹果鲜果样本制得的脆片综合得分范围为0.2069—0.7933,存在较大差异,得分排名前3的苹果样本为‘辽宁华红’‘辽宁华金’和‘山东烟富6号’,排名最后的苹果样本为‘陕西秦冠’。基于脆片核心指标与苹果果实品质指标相关性分析结果,筛选出苹果果实的果形指数、果肉a*值、pH、 展开更多
关键词 苹果 脆片 干制 适宜性评价 BP神经网络
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三种植物精油化学成分分析及体外抑菌活性研究 被引量:17
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作者 牛彪 金川 +5 位作者 梁剑平 尚若锋 郝宝成 王学红 杨珍 刘宇 《动物医学进展》 北大核心 2019年第12期18-23,共6页
为了研究肉桂、山苍子、迷迭香植物精油化学成分及体外抑菌活性,采用滤纸片法测定抑菌圈直径,通过肉汤稀释法和点种法测定其最小抑菌浓度(MIC)、最小杀菌浓度(MBC),并通过气相-质谱法(GC-MS)测定各植物精油的成分及含量。结果显示,肉桂... 为了研究肉桂、山苍子、迷迭香植物精油化学成分及体外抑菌活性,采用滤纸片法测定抑菌圈直径,通过肉汤稀释法和点种法测定其最小抑菌浓度(MIC)、最小杀菌浓度(MBC),并通过气相-质谱法(GC-MS)测定各植物精油的成分及含量。结果显示,肉桂精油浓度在1.118%时就可将5种病原菌全部杀灭;山苍子精油浓度在4.75%时可将S.albus、S.aureus、E.coli、C.albians杀灭,而对P.aeruginosa的杀灭浓度大于9.5%;迷迭香精油在浓度9.5%可将S.albus、S.aureus、C.albicans杀灭,而对E.coli、P.aeruginosa的杀灭浓度大于9.5%。GC-MS结果显示,肉桂精油主要组分为肉桂醛(83.57%)、2′-甲氧基肉桂醛(5.96%),香豆素(2.90%);山苍子精油包括柠檬醛(21.45%)、双戊烯(21.88%)、(Z)-3,7-二甲基-2,6-辛二烯醛(20.96%);迷迭香精油主要含有α-蒎烯(24.09%)、桉树脑(25.81%)、左旋樟脑(25.09%)、异龙脑(9.28%)。结果表明,3种植物精油具有广谱的抑菌活性,能够为开发新型、绿色、安全、高效的抗生素替代品提供理论依据。 展开更多
关键词 植物精油 滤纸片法 最小抑菌浓度 最小杀菌浓度 气相-质谱法
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不同部位烤烟挥发性有机酸含量与烟叶品质的关系分析 被引量:16
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作者 陈思昂 张环纬 +5 位作者 陈彪 金伊楠 朱智威 魏烁果 李东亮 许自成 《河南农业科学》 北大核心 2019年第2期54-62,共9页
为了解不同部位烤烟挥发性有机酸含量和烟叶品质之间的关系,选取我国11个产区297份不同部位陈化烟叶,测定挥发性有机酸含量并对其进行描述统计,采用简单相关分析、回归分析、典型相关分析的方法,探讨不同部位烤烟挥发性有机酸含量与化... 为了解不同部位烤烟挥发性有机酸含量和烟叶品质之间的关系,选取我国11个产区297份不同部位陈化烟叶,测定挥发性有机酸含量并对其进行描述统计,采用简单相关分析、回归分析、典型相关分析的方法,探讨不同部位烤烟挥发性有机酸含量与化学指标、感官评价指标的关系。结果表明,上、中、下部叶挥发性有机酸平均含量分别为15.63、13.56、11.92μg/g,且各个部位间差异极显著。各部位烟叶挥发性有机酸含量与化学指标的相关性不同,其中,挥发性有机酸总量与pH值、钾含量呈负相关。各个部位挥发性有机酸含量与感官评吸指标也有不同程度的相关性,挥发性有机酸总量对口感特性影响较大,上部叶挥发性有机酸含量与感官评吸指标呈正相关,中、下部叶挥发性有机酸含量与感官评吸指标呈负相关。典型相关分析表明,上部叶正丁酸、异戊酸、己酸含量对浓度、香气量影响明显,壬酸、庚酸含量对杂气、余味影响较明显;中部叶β-甲基戊酸、异戊酸、己酸含量对浓度影响较大;挥发性有机酸总量中异戊酸、己酸含量对香气质、浓度影响明显,戊酸、辛酸含量对劲头、刺激性影响明显。综合分析,上、中、下部叶挥发性有机酸含量均对pH值、余味、刺激性有着显著影响。为实现优质烟叶生产,应采取适当措施增加上部叶挥发性有机酸含量,适当调控中、下部叶挥发性有机酸含量,以提高烟叶品质。 展开更多
关键词 烤烟 挥发性有机酸 部位 化学品质 感官评价
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Broadband tunable liquid crystal terahertz waveplates driven with porous graphene electrodes 被引量:14
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作者 Lei Wang Xiao-Wen Lin +10 位作者 Wei Hu Guang-Hao Shao Peng Chen Lan-Ju Liang biao-Bing jin Pei-Heng Wu Hao Qian Yi-Nong Lu Xiao Liang Zhi-Gang Zheng Yan-Qing Lu 《Light(Science & Applications)》 SCIE EI CAS CSCD 2015年第1期477-482,共6页
Versatile devices,especially tunable ones,for terahertz imaging,sensing and high-speed communication,are in high demand.Liquid crystal based components are perfect candidates in the optical range;however,they encounte... Versatile devices,especially tunable ones,for terahertz imaging,sensing and high-speed communication,are in high demand.Liquid crystal based components are perfect candidates in the optical range;however,they encounter significant challenges in the terahertz band,particularly the lack of highly transparent electrodes and the drawbacks induced by a thick cell.Here,a strategy to overcome all these challenges is proposed:Few-layer porous graphene is employed as an electrode with a transmittance of more than 98%.A subwavelength metal wire grid is utilized as an integrated high-efficiency electrode and polarizer.The homogeneous alignment of a high-birefringence liquid crystal is implemented on both frail electrodes via a non-contact photo-alignment technique.A tunable terahertz waveplate is thus obtained.Its polarization evolution is directly demonstrated.Furthermore,quarter-wave plates that are electrically controllable over the entire testing range are achieved by stacking two cells.The proposed solution may pave a simple and bright road toward the development of various liquid crystal terahertz apparatuses. 展开更多
关键词 liquid crystal porous graphene terahertz waveplate
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高速列车车轮多边形对车内噪声的影响(英文) 被引量:14
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作者 Jie ZHANG Guang-xu HAN +3 位作者 Xin-biao XIAO Rui-qian WANG Yue ZHAO Xue-song jin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2014年第12期1002-1018,共17页
研究目的:研究高速列车车轮多边形特征对轮轨噪声和车内噪声的影响规律,讨论目前国内高速列车车轮镟修指标的不足,为高速列车车轮镟修方法的优化改进提供科学依据。创新要点:系统分析高速列车车轮多边形阶次、幅值和相位等参数对车内噪... 研究目的:研究高速列车车轮多边形特征对轮轨噪声和车内噪声的影响规律,讨论目前国内高速列车车轮镟修指标的不足,为高速列车车轮镟修方法的优化改进提供科学依据。创新要点:系统分析高速列车车轮多边形阶次、幅值和相位等参数对车内噪声的影响规律;提出车轮镟修中仅考虑车轮径跳作为限值是不够的。研究方法:1.基于线路试验,初步分析高速列车车轮多边形状态对车内噪声的影响,进而对车轮多边形特征进行剖析;2.基于带通滤波和快速傅里叶变换,使用MATLAB程序生成不同阶次、幅值和相位的车轮多边形粗糙度数据;3.基于TWINS轮轨噪声原理,使用HWTNS预测含有不同车轮多边形特性的轮轨噪声;4.基于混合有限元-统计能量分析(FE-SEA)方法,建立高速列车客室端部车内噪声预测模型,预测车内噪声;5.通过分析车轮多边形参数、车轮径跳和车内噪声之间的相互关系,研究目前的高速列车车轮镟修指标是否合适。重要结论:1.高速列车车轮径跳值相同,但车轮多边形状态不同时,轮轨噪声与车内噪声有明显差异;2.当车轮多边形幅值相同时,高阶多边形可以引起更高的轮轨噪声和车内噪声;3.改变车轮多边形的相位,可以获得不同的车轮径跳值,但是对轮轨噪声和车内噪声几乎没有影响。 展开更多
关键词 高速列车 车轮多边形 镟修 车内噪声 轮轨噪声
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不同速度高速列车车外噪声的调查研究(英文) 被引量:14
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作者 Bin HE Xin-biao XIAO +2 位作者 Qiang ZHOU Zhi-hui LI Xue-song jin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2014年第12期1019-1033,共15页
研究目的:基于声源识别,得出车外噪声分布特性及场点主要噪声源。创新要点:1.研究高速列车噪声源强特性及频谱特性;2.揭示不同速度下不同声源频谱变化规律;3.分析车外声场场点噪声变化规律及主要声源。研究方法:1.利用车外声源识别系统(... 研究目的:基于声源识别,得出车外噪声分布特性及场点主要噪声源。创新要点:1.研究高速列车噪声源强特性及频谱特性;2.揭示不同速度下不同声源频谱变化规律;3.分析车外声场场点噪声变化规律及主要声源。研究方法:1.利用车外声源识别系统(图2)分析高速列车声源分布规律及频谱特性;2.利用声源的垂向(图10)分布研究不同声源在各频率下垂向分布规律;3.利用场点声源与速度的拟合关系(图16)研究场点主要噪声源。重要结论:1.高速列车车外噪声源主要分布在轮轨区域、受电弓和车间连接区域;2.轮轨区域噪声包括滚动噪声和气动噪声,在各频率均为最显著声源;3.在整个列车高度,轮轨滚动噪声对总噪声贡献率大于气动噪声;4.车外场点噪声主要频率为630–2500 Hz,主要来自轮轨滚动噪声。 展开更多
关键词 车外噪声 声源识别 高速铁路 声暴露级 通过噪声
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Characteristics of interior noise of a Chinese high-speed train under a variety of conditions 被引量:13
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作者 Jie ZHANG Xin-biao XIAO +3 位作者 Xiao-zhen SHENG Rong FU Dan YAO Xue-song jin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2017年第8期617-630,共14页
This paper presents an investigation into the characteristics of interior noise of a Chinese high-speed train under several typical conditions. Interior noises within Vehicle TC01, which can be used as a head car or a... This paper presents an investigation into the characteristics of interior noise of a Chinese high-speed train under several typical conditions. Interior noises within Vehicle TC01, which can be used as a head car or an end car, and Vehicle TP03, the third car counting from TC01, are measured for the train running at speeds from 260 km/h to 385 km/h, along two types of track including a slab track and a ballast track and either on the ground surface or in a tunnel. Data analyses are performed for sound pressure overall levels, frequency, area contributions, and possible generation mechanisms, showing how they are affected by train speed, running direction, track type, and tunnel. The results show that, whether TC01 is used as head car or end car, the interior noise characteristics in the VIP cabin are mostly related to aerodynamic noise. Differences in interior noise between tracks become smaller as the train speed increases. The effect of a tunnel on the interior noise is more important for the middle coach than that for the head coach. This study can provide a basis for noise control of high-speed trains. 展开更多
关键词 High-speed train Interior noise Noise source identification Contribution analysis Various conditions Noise characterization
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Spatiotemporal Dynamics of the BRI1 Receptor and its Regulation by Membrane Microdomains in Living Arabidopsis Cells 被引量:12
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作者 Li Wang Hong Li +9 位作者 Xueqin Lv Tong Chen Ruili Li Yiqun xuei Jianjun Jiang biao jin Frantisek Baluska Jozef Samaj Xuelu Wang jinxing Lin 《Molecular Plant》 SCIE CAS CSCD 2015年第9期1334-1349,共16页
The major brassinosteroid (BR) receptor of Arabidopsis BRASSINOSTEROID INSENSITIVE1 (BRI1) plays fundamental roles in BR signaling, but the molecular mechanisms underlying the effects of BR on BRI1 internalization... The major brassinosteroid (BR) receptor of Arabidopsis BRASSINOSTEROID INSENSITIVE1 (BRI1) plays fundamental roles in BR signaling, but the molecular mechanisms underlying the effects of BR on BRI1 internalization and assembly state remain unclear. Here, we applied variable angle total internal reflection fluorescence microscopy and fluorescence cross-correlation spectroscopy to analyze the dynamics of GFP-tagged BRII. We found that, in response to BR, the degree of co-localization of BRI1-GFP with AtFIotl-mCherry increased, and especially BR stimulated the membrane microdomain-associated pathway of BRI1 internalization. We also verified these observations in endocytosis-defective chc2-1 mutants and the AtFIotl amiRNA 15-5 lines. Furthermore, examination of the phosphorylation status of bril-EMS-suppressor 1 and measurement of BR-responsive gene expression revealed that membrane microdomains affect BR signaling. These results suggest that BR promotes the partitioning of BRI1 into functional membrane microdomains to activate BR signaling. 展开更多
关键词 BRI1 BR signaling ENDOCYTOSIS membrane microdomains spatiotemporal dynamics
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