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Effects of mesoclimate and microclimate variations mediated by high altitude and row orientation on sucrose metabolism and anthocyanin synthesis in grape berries
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作者 Haining Yin Zhaoxiang Wang +3 位作者 Lin Wang Jianhong Cao Jiakui Wang Zhumei Xi 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期713-731,共19页
Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with ... Climate change and extreme weather pose significant challenges to the traditional viticulture regions.Emerging high-altitude grape-producing regions with diverse orientations have shown great potential in coping with this challenge.Stable,high-quality wine grape production may be achieved by synchronizing the meso-and microclimate.To clarify the role of high altitude and row orientation in meso-and microclimate and the response of berries to it,we evaluated seven years(2012-2018)of climate data,two years of basic grape(Cabernet Sauvignon,Vitis vinifera L.)quality,and one-year microclimate from veraison to harvest.By comparing two locations(Sidon 2047 m,Sinon 2208 m)in Yunnan Province,China,we found that the average temperature has been stable at approximately 15℃ for seven years,with no extreme weather or,noticeable global warming.The light intensity(LI)in the north-south(NS)was more balanced than the east-west(EW)direction,and the east-west to the south(EW-S)canopy side was almost higher than the other sides.High LI was associated with high photosynthetically active radiation(PAR),ultraviolet(UV),and infrared(IR)light and vice versa.The north-south to the east(NS-E)and east-west to the north(EWN)sides were characterized by lower LI and higher UV and IR light,and higher total anthocyanin content.Most anthocyanin synthesis-related genes,for example,VvF3'H and VvF3'5'H,were highly expressed in NS-E from veraison to maturity.Perhaps UV and IR light induced their expression.This study provides new insights on the role of differently orientated rows in controlling grape quality due to varied light quality.The findings are globally significant,particularly in the context of climate change,and offer fresh insights into berry physiological responses and decision-making for the management of existing vineyards. 展开更多
关键词 vitis vinifera l. Orientated rows Berry composition SUGAR PHENOlIC light quality Solar radiation
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基于YOLO v5l-Im的排水管道缺陷检测方法及效果分析
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作者 王俊岭 王晨晨 熊玉华 《科学技术与工程》 北大核心 2024年第18期7833-7842,共10页
针对YOLO v5l(you only look once version 5 large)算法对于小目标、少样本且背景复杂的排水管道缺陷图像检测的精度低、误检和漏检率较高等问题,提出了一种基于YOLO v5l-Im算法的排水管道缺陷检测改进方法。做了三点改进:首先提出了Fo... 针对YOLO v5l(you only look once version 5 large)算法对于小目标、少样本且背景复杂的排水管道缺陷图像检测的精度低、误检和漏检率较高等问题,提出了一种基于YOLO v5l-Im算法的排水管道缺陷检测改进方法。做了三点改进:首先提出了Focal-EIoU(focal embedding intersection over union)损失函数,有效提升了检测模型的性能;其次为增强检测模型对小目标缺陷的检测效果,减少缺陷误检和漏检的概率,将骨干网络中浅层特征图融合到双向特征金字塔网络(bidirectional feature pyramid network,BiFPN)中,增加针对小目标的预测层;最后在YOLO v5l中引入坐标注意力机制(coordinate attention,CA),提高模型对图像中感兴趣区域的敏感程度,减少冗余背景信息的干扰。3种改进对平均检测准确率(mean average precision,mAP)的提升分别为2.0、2.9、5.9个百分点。将三种有效改进融合到一起,检测结果表明:本文提出的YOLO v5l-Im模型的mAP达到了92.1%,较原模型的85.5%提升了6.5个百分点。由此可见,所做的改进有效增强了YOLO v5l对排水管道缺陷的检测能力。 展开更多
关键词 排水管道缺陷检测 YOlO v5l Focal-EIoU损失函数 BiFPN特征网络 CA注意力模块 融合检测
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欧亚种葡萄(Vitis vinifera L.)的驯化及分类研究进展 被引量:12
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作者 王军 段长青 《中国农业科学》 CAS CSCD 北大核心 2010年第8期1643-1654,共12页
欧亚种葡萄是世界上广泛栽培的具有重要经济价值的果树。一般认为欧亚种葡萄栽培亚种是由其野生亚种驯化而来,这个驯化过程包括对色泽引人的大果穗、含糖量高、两性花类型的选择和无性繁殖技术的发现,欧亚种葡萄的驯化问题主要涉及驯化... 欧亚种葡萄是世界上广泛栽培的具有重要经济价值的果树。一般认为欧亚种葡萄栽培亚种是由其野生亚种驯化而来,这个驯化过程包括对色泽引人的大果穗、含糖量高、两性花类型的选择和无性繁殖技术的发现,欧亚种葡萄的驯化问题主要涉及驯化事件发生的时间、地点和数量。本文综述了欧亚种葡萄的驯化和生态地理起源与分布分类研究进展。 展开更多
关键词 欧亚种葡萄 起源 驯化 生态地理分类
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葡萄(Vitis vinifera L.)试管繁殖中芽增殖能力衰减的原因及其防治方法的研究
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作者 范子南 肖华山 曾焕泰 《福建师范大学学报(自然科学版)》 CAS CSCD 1992年第4期74-79,共6页
以20个葡萄品种试管苗作为实验材料,经四年、四十多代的继代培养反复对比实验发现:在葡萄试管繁殖中,连续恒温(25±1℃)条件下培养或只采用固体培养方法,不适期进行继代培养均会导致芽增殖能力的衰减,根据生物统计分析,当继代培养超... 以20个葡萄品种试管苗作为实验材料,经四年、四十多代的继代培养反复对比实验发现:在葡萄试管繁殖中,连续恒温(25±1℃)条件下培养或只采用固体培养方法,不适期进行继代培养均会导致芽增殖能力的衰减,根据生物统计分析,当继代培养超过16~17代后,芽增殖能力即随着继代培养次数的增加而逐渐下降,采取变温培养、变换培养方法、适期继代培养或在增殖培养基中附加适量的椰子乳汁等方法均可防治芽增殖能力的哀减,保持高的芽增殖能力。 展开更多
关键词 葡萄 组织培养 芽增殖
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罕见EGFR L833V/H835L复合突变的肺腺癌患者1例及文献回顾
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作者 缪永恩 汪瑜堃 +4 位作者 李萍 谈敏 文婷婷 王昌惠 谢栓栓 《中国肺癌杂志》 CAS CSCD 北大核心 2023年第10期795-800,共6页
表皮生长因子受体(epidermal growth factor receptor,EGFR)突变是非小细胞肺癌(non-small cell lung cancer,NSCLC)发生发展过程中最常见的驱动基因,其中18-21号外显子的突变常见,尤其是19号外显子的缺失和21号外显子L858R点突变最为常... 表皮生长因子受体(epidermal growth factor receptor,EGFR)突变是非小细胞肺癌(non-small cell lung cancer,NSCLC)发生发展过程中最常见的驱动基因,其中18-21号外显子的突变常见,尤其是19号外显子的缺失和21号外显子L858R点突变最为常见,但是EGFR L833V/H835L罕见基因复合突变的发生率非常低,患者数量很少,相关临床数据和治疗方法的证据也不足。部分EGFR-酪氨酸激酶抑制剂(EGFR-tyrosine kinase inhibitors,EGFR-TKIs)在治疗伴有罕见基因突变的肺癌患者方面同样具有良好疗效。本文报道了1例携带EGFR L833V/H835L罕见基因复合突变的NSCLC患者,在给予阿法替尼治疗5个月后,计算机断层扫描(computed tomography,CT)显示肺部病灶缩小,患者对阿法替尼联合安罗替尼治疗反应良好。同时,我们还对以往报道的EGFR L833V/H835L罕见基因复合突变的NSCLC患者进行了整理,总结了该类患者的特点及应用不同种类EGFR-TKIs治疗的效果。 展开更多
关键词 肺肿瘤 表皮生长因子受体 复合突变 l833v/H835l 阿法替尼
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葡萄(Vitis Vinifera L.)X-射线能谱元素微区污染分析研究
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作者 周劲松 杨海燕 《青海大学学报(自然科学版)》 2002年第3期6-7,共2页
对葡萄果实不同处理的细胞组织多位点进行X -射线能谱微区元素分析。结果 :葡萄不同处理的细胞组织中共发现Mg、Al、Si、P、S、Cl、K、Ca、Fe、Cu十种元素。且不同处理的组织细胞中各元素含量分布有差异 ,未清洗果实表皮处理的Al、Si、S... 对葡萄果实不同处理的细胞组织多位点进行X -射线能谱微区元素分析。结果 :葡萄不同处理的细胞组织中共发现Mg、Al、Si、P、S、Cl、K、Ca、Fe、Cu十种元素。且不同处理的组织细胞中各元素含量分布有差异 ,未清洗果实表皮处理的Al、Si、S、Ca、Cu含量均显著高于对照 。 展开更多
关键词 污染分析 葡萄 果实污染 X-射线能谱微区分析法 重金属化学污染 元素分析
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The Establishment of an Agrobacterium-Mediated Transformation Platform for the Non-Embryogenic Calli of Vitis vinifera L. 被引量:3
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作者 ZHAO Feng-xia CHEN Shang-wu +3 位作者 Perl Avihai DAI Ru XU Hai-ying MA Hui-qin 《Agricultural Sciences in China》 CAS CSCD 2011年第5期686-694,共9页
Non-embryogenic calli (NEC) was inevitably and heavily produced when grape embryogenic calli (EC) was induced from explants or during the subculture of EC.A stable and highly efficient NEC transformation platform ... Non-embryogenic calli (NEC) was inevitably and heavily produced when grape embryogenic calli (EC) was induced from explants or during the subculture of EC.A stable and highly efficient NEC transformation platform is required to further sort out and verify key genes which determine/switch the identity of NEC and EC.In this research,a vector pA5 containing a chitinase signal sequence fused to gfp (green fluorescent protein) and an HDEL motive was used to target and immobilize into Agrobacterium strain EHA105 to establish a transformation platform for Vitis vinifera L.cv.Chardonnay NEC.It was determined that NEC 10 d after subculture was the best target tissue;30 min for inoculation followed by 3 d co-cultivation with the addition of 200 μmol L-1 acetosyringone (AS) was optimized as protocol.The use of bacterial densities as 1.0 at OD600 did not result in serious tissue hypersensitive reaction and it had higher efficiency.Kanamycin at 200 mg L-1 was picked for positive expression selection.The stable transformation of NEC was proved by reverse transcription-polymerase chain reaction techniques (RT-PCR) and fluorescent microscopy after three sub-cultures of the selected cell line.Highly efficient genetic transformation protocol of grape NEC was achieved and some of the optimized parameters were different from that reported for EC.This transformation platform could facilitate the verification of candidate somatic embryogenesis (SE) decisive genes,and the successfully transformed NEC with certain genes can also be used as bioreactors for the production of functional products,as NEC not only proliferates fast,but also keeps in a rather stable condition. 展开更多
关键词 Agrobacterium tumefaciens non-embryogenic calli TRANSFORMATION vitis vinifera l. RT-PCR
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Cloning and Characterization of WOX4 Gene from Vitis vinifera L. Involved in Stem Cell Regulation 被引量:3
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作者 DAI Ru JIN Hai-peng +5 位作者 WANG Zeng Avihai Perl XU Hai-ying ZHANG Wen CHEN Shang-wu MA Hui-qin 《Agricultural Sciences in China》 CAS CSCD 2011年第12期1861-1871,共11页
Wuschel-related homeobox (WOX) genes play essential, specific, and sometimes redundant roles in plant embryo development, shoot and root meristem maintenance, and plant development. Though much information was quick... Wuschel-related homeobox (WOX) genes play essential, specific, and sometimes redundant roles in plant embryo development, shoot and root meristem maintenance, and plant development. Though much information was quickly gained with members of the WOX gene family of Arabidopsis, monocotyledonous crops, and gymnospermous conifers, little is known about perennial woody plants. In this study, we isolated the first WOXgene family member from grape (Vitis vinifera L. cv. Cabernet Sauvignon), and named it VvWOX4 based on its characteristic domains and phylogenetic analysis. The identity of VvWOX4 was validated by MALDI-TOF MS and Western blot with polyclonal antibody against Arabidopsis thaliana Wuschel. Functional analysis showed that VvWOX4 markedly increased shoot primordia structures when overexpressed under CaMV 35S promoter in tobacco. A different expression pattern was found for VvVOX4 compared with AtWUCHEL and its expression was detected in unique organs of grapevines. Besides the expression in the vegetative shoot apical meristem (SAM) of grape shoot tips, VvWOX4 is expressed in dormant winter buds, inflorescence, young leaves, and tendril tips, but not in root tips. In young leaves, the expression of VvWOX4 is strongly upregulated by wounding, and also by plant growth regulators such as 2 mg L-1 2,4-D, 1 mg L-1 NAA and 1 mg L-1 BAP treatments, while downregulation was monitored by 1 mg L^-1 IBA treatment, and there was no response to 0.5 mg L-1 GA3 treatment. Together, our results revealed the first member of grape WOX gene family and indicated different roles and regulation of VvWOX4 in the perennial woody crop grapevine. 展开更多
关键词 expression characteristics gene cloning plant hormone induced expression Htis vinifera l. WOX4
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Somatic embryogenesis and histological analysis from zygotic embryos in Vitis vinifera L.‘Moldova’ 被引量:3
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作者 LI Hui LI Feng-lan +2 位作者 DU Jing-chuan LU Hai HE Zheng-quan 《Forestry Studies in China》 CAS 2008年第4期253-258,共6页
We examined the somatic embryogenesis from and histological studies of zygotic embryos of seeds in European Grape 'Moldova' (Vitis vinifera U 'Moldova'). Primary calli were initiated on Nitsch and Nitsch (NN) ... We examined the somatic embryogenesis from and histological studies of zygotic embryos of seeds in European Grape 'Moldova' (Vitis vinifera U 'Moldova'). Primary calli were initiated on Nitsch and Nitsch (NN) medium supplemented with 1.0 mg·L^-1 2,4-D and 0.5 mg·L^-1 6-BA. Embryogenic calli were produced upon transfer to a NN medium with 0.5 mg·L^-1 6-BA and 2 mg·L^-1 NAA and somatic embryos were obtained on a half strength MS medium without plant growth regulators. During the somatic embryo germination, an addition of 1.0 mg·L^-1 6-BA in the medium could accelerate somatic embryos to develop into normal plants and increase the conversion rate from 0 to 43.3%. Histological studies of embryogenic calli and somatic embryos demonstrated dynamic changes of proteins and starch grains. The developmental processes of somatic embryos were similar to those of zygotic embryos, including typical epiderma, cotyledon primordium and vascular tissue. 展开更多
关键词 zygotic embryo somatic embryo HISTOlOGY vitis vinifera l.
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Anthocyanin profi les and color properties of red wines made from Vitis davidii and Vitis vinifera grapes 被引量:6
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作者 Yanlun Ju La Yang +5 位作者 Xiaofeng Yue Yunkui Li Rui He Shenglin Deng Xin Yang Yulin Fang 《Food Science and Human Wellness》 SCIE 2021年第3期335-344,共10页
Spine grape(Vitis davidii Foex.)is an important wild grape species native to China.Fifteen red spine grape clones and three red Vitis vinifera grape varieties were used to evaluate the differences in the anthocyanin p... Spine grape(Vitis davidii Foex.)is an important wild grape species native to China.Fifteen red spine grape clones and three red Vitis vinifera grape varieties were used to evaluate the differences in the anthocyanin profiles and color properties of wines made from V.davidii and V.vinifera grapes.Among spine wines,‘Junzi#2’wine had the highest total phenolic and total anthocyanin,‘Xiangzhenzhu’wine had the highest total flavonoids,and‘Junzi#1’wine had the highest total tannin.The anthocyanin compositions of all of the spine wines were dominated by Mv-3,5-diglucoside.The total individual anthocyanin contents in spine wines,except‘Gaoshan#5’,‘Junzi#5055’,‘Junzi#5061’,and‘Junzi#5044’,were signifi cantly higher than in V.vinifera wines.Most of the spine wines had a stronger red intensity and a brighter chroma with a bluer hue than V.vinifera wines.Correlation analysis revealed that the color properties were closely related to the anthocyanin composition.These results suggest that wines made from spine grapes may be useful for the wine industry for their color properties and high individual anthocyanin contents. 展开更多
关键词 Spine grape vitis vinifera l. Wine analysis Wine color ANTHOCYANIN
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The potential role of grape (Vitis vinifera L.) in prevention of threatened abortion via immunomodulatory and anti-inflammatory abilities: a hypothesis 被引量:4
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作者 Malihe Tabarrai Mozhgan Mehriardestani +2 位作者 Sharareh Hekmat Fatemeh Nejatbakhsh Fatemeh Moradi 《Traditional Medicine Research》 2019年第3期131-139,共9页
Threatened abortion is a common problem in early pregnancy. This early vaginal bleeding happens in about 25% of pregnant women. The medications including progesterone, uterine muscle relaxant or human chorionic gonado... Threatened abortion is a common problem in early pregnancy. This early vaginal bleeding happens in about 25% of pregnant women. The medications including progesterone, uterine muscle relaxant or human chorionic gonadotropin have essential effects in developing pregnancy, but the clinical data are insufficient to prescribe them. In recent decades, medicinal herbs can help us to present new treatments. Grape (Vitis vinifera L.) can protect the fetus from the perspective of Persian medicine. So, we hypothesize about the salutary effects of grape in miscarriage prevention. We found five standard expected mechanisms of grape to prevent threatened abortion: immunomodulatory and anti-inflammatory, anti-oxidant, anti-contraction, hormonal and anti-stress activities. Grape reduces nitric oxide, prostaglandin E2, expression of nuclear factor κB and other pro-inflammatory cytokines like IL (Interleukin)-1β, IL-6, IL-8, and tumor necrosis factor-α. It also elevates anti-inflammatory mediators and expression of peroxisome proliferator-activated receptor-γ. Grape polyphenols have a crucial role in fetus protection with high antioxidant power and other functions such as prevention of stress-triggered abortion with proanthocyanidins, or hormonal effects and inhibition of uterine contractions with resveratrol. So according to these studies, grape probably has effects on the immune and endocrine factors involved in threatened miscarriage. 展开更多
关键词 vITIS vinifera l. GRAPE Oxidation Immunomodulation Inflammation ABORTION PERSIAN medicine
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“NP_([L])+V+着+NP”格式乙类结构歧义产生的原因和机制探析
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作者 骆明弟 《同济大学学报(社会科学版)》 北大核心 2023年第1期117-128,共12页
“NP_([L])+V+着+NP”格式一直是学界关注的热点,有学者将其分化为“静态”A式和“动态”B式,并指出A式、B式对立的原因,让人们认识到了“NP_([L])+V+着+NP”格式实际上是一个歧义格式。然而,该格式歧义产生的原因和机制并未受到关注和... “NP_([L])+V+着+NP”格式一直是学界关注的热点,有学者将其分化为“静态”A式和“动态”B式,并指出A式、B式对立的原因,让人们认识到了“NP_([L])+V+着+NP”格式实际上是一个歧义格式。然而,该格式歧义产生的原因和机制并未受到关注和研究,前期学者只从结果的角度提出“重合说”来解释歧义的产生:当A式、B式重合时产生歧义。其实,从过程的角度揭示该格式歧义的原因和机制,才更有解释力。根据歧义产生的情况,“NP_([L])+V+着+NP”格式可以分成甲、乙、丙三类,只有乙类结构有歧义的可能。乙类结构产生歧义的原因和机制在于:乙类结构动词“动作进行”义、“状态持续”义的内在共生性以及此二义都被“容主性”NP_([L])激活,前者是歧义产生的内在基础,后者是歧义实现的关键。动词的“动作进行”义浮现生成了结构的“动态进行”义,动词的“状态持续”义浮现生成了结构的“静态存在”义。 展开更多
关键词 NP_([l])%PlUS%v%PlUS%着%PlUS%NP格式 乙类结构 歧义 容主性
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D816V突变型KIT特异性诱导COS-1非洲绿猴肾细胞核不均一核糖核蛋白 L(HNRNPL)和HNRNPK磷酸化
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作者 张良颖 张少婷 +4 位作者 范朝阳 蒋宗英 李淑璟 刘安步 孙建民 《细胞与分子免疫学杂志》 CAS CSCD 北大核心 2023年第2期138-143,共6页
目的探究Ⅲ类酪氨酸激酶受体KIT D816V突变对核不均一核糖核蛋白L(HNRNPL)和HNRNPK的调控作用。方法在COS-1非洲绿猴肾细胞表达野生型KIT或KIT D816V,或与HNRNPL或HNRNPK共表达,用免疫沉淀法和Western blot法检测KIT活化及HNRNPL、HNRNP... 目的探究Ⅲ类酪氨酸激酶受体KIT D816V突变对核不均一核糖核蛋白L(HNRNPL)和HNRNPK的调控作用。方法在COS-1非洲绿猴肾细胞表达野生型KIT或KIT D816V,或与HNRNPL或HNRNPK共表达,用免疫沉淀法和Western blot法检测KIT活化及HNRNPL、HNRNPK的磷酸化,通过激光共聚焦显微镜检测KIT、HNRNPL、HNRNPK在COS-1细胞中的定位。结果野生型KIT需要其配基干细胞因子(SCF)的刺激发生活化,而KIT D816V无需SCF刺激即可发生自活化。此外,KIT D816V可诱导HNRNPL和HNRNPK发生磷酸化,而野生型KIT无此功能。HNRNPL和HNRNPK在细胞核表达,野生型KIT在细胞膜和细胞质表达,而KIT D816V主要表达于细胞质。结论野生型KIT活化需要其配体SCF参与,而KIT D816V无需SCF刺激即可发生自活化,并能特异性诱导HNRNPL和HNRNPK磷酸化。 展开更多
关键词 KIT D816v 核不均一核糖核蛋白l(HNRNPl) 核不均一核糖核蛋白K(HNRNPK)
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The Influence of Photoperiod on the Regulation of Root and Callus Initiation of Perle Noir (<i>V. vinifera</i>L.): Expression of MADS-Box Gene
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作者 Henda Cheikhrouhou Manel Zrida Bechir Ezzili 《Agricultural Sciences》 2015年第9期908-915,共8页
To study the influence of photoperiod on roots differentiation in the Tunisian grapevine (Vitis vinifera L.) cultivar Perle noir, roots and callus initiation were analyzed under three different conditions of day lengt... To study the influence of photoperiod on roots differentiation in the Tunisian grapevine (Vitis vinifera L.) cultivar Perle noir, roots and callus initiation were analyzed under three different conditions of day length: long day (LD), short day (SD) and darkness (D). The photoperiod influenced the number of callus and roots per cuttings;it has a significant effect on the roots and callus initiation. Expression profile analysis of six MADS-box genes (VTM8, VSEP2, VAG12, VAG17-1, VAG17-2 and VSOC1.3) during root and callus development is in agreement with the above-mentioned observation. The expression of the MADS-box genes during root and callus development fluctuated in a tissue-dependent manner. These data suggest that all genes are expressed in roots under three photoperiods. Total darkness gives the number of the most important root per cutting compared to the other two conditions. This photoperiodic condition gave the most important expression of the studied genes VAG12, VAG17-2, VAG17-1, VTM8 and VSEP2 transcripts were not found in callus grown in the dark or in LD conditions, respectively. VSOC1.3 transcripts were not found in callus grown in the dark or in SD conditions, respectively. Transcript abundance of VTM8 and VSOC1 was highest in LD. 展开更多
关键词 Grapevine ROOT PHOTOPERIOD MADS-Box Genes CAllUS vitis vinifera l.
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Rooting Abilities in <i>Vitis vinifera</i>L.: Total Lipid and Fatty Acids Evolution in Perle Noir Cutting
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作者 Henda Cheikhrouhou Manel Zrida Bechir Ezzili 《Agricultural Sciences》 2015年第5期498-504,共7页
Rooting ability in Vitis vinifera L. is the phenomena studied. The evolution of the total lipids contents and fatty acids amount of cuttings during the rooting were determined. Total lipid extraction was carried out b... Rooting ability in Vitis vinifera L. is the phenomena studied. The evolution of the total lipids contents and fatty acids amount of cuttings during the rooting were determined. Total lipid extraction was carried out by an extraction solvent consisting of a mixture of chloroform and methanol. Methylation of fatty acids was carried out by the boron trifluoride methanol complex. Their analysis is performed by gas chromatography. We have obtained a content of merithallus lipids equivalent with then in bibliography. In other hand 3 fatty acids were obtained: eicosapentaenoic acid, oleic acid and docosanoic acid. Among the studied of rooting abilities, we observed decreased levels of total lipids and in the essential fatty acids: eicosapentaenoic acid C20:5 n-3 and oleic acid C18:1 n-9. Minor fatty acids cuttings experimental have a variable evolution. Lipids and certain fatty acids may be markers of rooting in the vine. 展开更多
关键词 lipids CUTTING Fatty Acids ROOTING Perle Noir vITIS vinifera l.
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基于CH32V303的微型四旋翼无人机控制系统设计
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作者 宋朝晖 马锋 《电子制作》 2024年第9期3-6,共4页
设计了一款基于RISC-V内核微控制器的微型四旋翼无人机,采用CH32V303单片机作为无人机控制系统的核心控制芯片。遥控器通过2.4G无线模块NRF24L01与无人机主控制器进行通信;主控制器利用MPU6050采集无人机的实时加速度和角速度信息,并通... 设计了一款基于RISC-V内核微控制器的微型四旋翼无人机,采用CH32V303单片机作为无人机控制系统的核心控制芯片。遥控器通过2.4G无线模块NRF24L01与无人机主控制器进行通信;主控制器利用MPU6050采集无人机的实时加速度和角速度信息,并通过MPU自带的DMP解算出姿态角度,结合串级PID算法控制PWM输出,实现对无人机四个电机的转速控制,最终完成了无人机的稳定飞行。 展开更多
关键词 RISC-v 微型四旋翼无人机 CH32v303 NRF24l01 MPU6050 串级PID
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皖北方言的“V+搁+N(L)”格式 被引量:8
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作者 张德岁 唐爱华 《语言科学》 CSSCI 北大核心 2011年第2期219-224,共6页
皖北方言的"V+X+N(L)"格式中的"X"来源于动词"搁"的虚化,"V+搁+N(L)"格式,只有在"V"是无界的、持续性的动词时,才可以变换成"搁+N(L)+V"格式,"搁"的用法既不等... 皖北方言的"V+X+N(L)"格式中的"X"来源于动词"搁"的虚化,"V+搁+N(L)"格式,只有在"V"是无界的、持续性的动词时,才可以变换成"搁+N(L)+V"格式,"搁"的用法既不等同于普通话的"在"或"到",也不等同于其他方言区的"着"及其变体。在文艺作品中我们只发现了"搁+N(L)+V"格式,还没有发现"V+搁+N(L)"格式的用例。 展开更多
关键词 皖北方言 v%PlUS%X%PlUS%N(l)”格式 “X%PlUS%N(l)%PlUS%v”格式 结构特点 “搁”
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基于V4L2的视频设备驱动开发 被引量:42
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作者 徐家 陈奇 《计算机工程与设计》 CSCD 北大核心 2010年第16期3569-3572,共4页
在嵌入式系统上,特别是系统资源相对较少的情况下,良好的驱动结构设计能够有效地减少驱动的内存和CPU占用量,从而提高系统性能。V4L2是Linux下视频设备驱动开发的新框架,深入分析了V4L2的运行机制,在充分利用其特性的基础上,从减少系统... 在嵌入式系统上,特别是系统资源相对较少的情况下,良好的驱动结构设计能够有效地减少驱动的内存和CPU占用量,从而提高系统性能。V4L2是Linux下视频设备驱动开发的新框架,深入分析了V4L2的运行机制,在充分利用其特性的基础上,从减少系统资源消耗和提高驱动性能的角度出发,给出了一套有效的视频设备V4L2驱动开发方法。实验结果表明了该方法的有效性。 展开更多
关键词 v4l2 lINUX 视频设备 驱动性能 资源消耗
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V4L2在TMS320DM8168高清视频监控系统中的实现 被引量:5
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作者 杨振永 王延杰 +2 位作者 王明佳 韩秋蕾 陈怀章 《电视技术》 北大核心 2014年第13期215-219,共5页
随着科技社会的发展,安防监控领域视频设备的高清化已成为新的发展趋势。采用TI最新推出的达芬奇单片系统TMS320DM8168,设计了一套高清视频监控系统。主要介绍了V4L2在该系统中的实现,主要包括视频接口设计、V4L2采集设备驱动开发和V4L... 随着科技社会的发展,安防监控领域视频设备的高清化已成为新的发展趋势。采用TI最新推出的达芬奇单片系统TMS320DM8168,设计了一套高清视频监控系统。主要介绍了V4L2在该系统中的实现,主要包括视频接口设计、V4L2采集设备驱动开发和V4L2采集应用程序设计等内容。测试结果表明该系统中实现的V4L2驱动和应用程序能够为DM8168高清视频监控系统提供高清视频数据,具有良好的可靠性和稳定性。 展开更多
关键词 lINUX v4l2 高清 DM8168 监控 视频采集
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基于V4L2视频采集缓存机制应用与实现 被引量:11
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作者 张辉 李新华 +1 位作者 刘波 钱翔 《现代电子技术》 2010年第20期54-56,共3页
V4L是Linux针对视频设备的应用程序接口,V4L2为其升级版本,它修复了第一版的很多设计缺陷。然而它提供的常规读写函数并不能满足大数据量的高速传输,所以将缓存技术引入到视频采集领域可以提高系统的吞吐量。提出了一种双帧内存映射视... V4L是Linux针对视频设备的应用程序接口,V4L2为其升级版本,它修复了第一版的很多设计缺陷。然而它提供的常规读写函数并不能满足大数据量的高速传输,所以将缓存技术引入到视频采集领域可以提高系统的吞吐量。提出了一种双帧内存映射视频采集机制,由于不需要做数据拷贝动作,减少了读/写时限,因而可以提高视频采集性能。实验结果表明,采用双帧内存映射机制在视频采集时速度快,效率高,达到了预期的实验效果。 展开更多
关键词 v4l2 lINUX 视频采集 内存映射
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