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Fekete-Szego Problem Associated with k-th Root Transformation for the Inverse of Univalent Functions Defined by Quasi-Subordination
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作者 Dong GUO Huo TANG +1 位作者 En AO Zongtao LI 《Journal of Mathematical Research with Applications》 CSCD 2021年第5期454-460,共7页
In this paper, we estimate the Fekete-Szego functional with k-th root transform for the inverse of certain classes of analytic univalent functions using quasi-subordination.
关键词 univalent functions Fekete-Szego inequality k-th root transformation INVERSE quasi-subordination
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Establishment of an efficient Agrobacterium rhizogenes-mediated hairy root transformation method for subtropical fruit trees 被引量:1
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作者 Mao Yin Yonghua Jiang +4 位作者 Yingjie Wen Fachao Shi Hua Huang Qian Yan Hailun Liu 《Horticultural Plant Journal》 2025年第4期1699-1702,共4页
Agrobacterium tumefaciens-mediated transformation has been widely adopted for plant genetic engineering and the study of gene function(Krenek et al.,2015).This method is prevalent in the genetic transformation of herb... Agrobacterium tumefaciens-mediated transformation has been widely adopted for plant genetic engineering and the study of gene function(Krenek et al.,2015).This method is prevalent in the genetic transformation of herbaceous plants,with notable applications in species such as Arabidopsis(Yin et al.,2024),soybean(Zhang et al.,2024),rice(Zhang et al.,2020),and Chinese cabbage(Li et al.,2021).However,its application in fruit trees is limited.This is primarily due to their long growth cycles and lack of rapid,efficient,and stable transgenic systems,which severely hinders foundational research involving plant genetic transformation(Mei et al.,2024).Furthermore,for subtropical fruit trees,the presence of recalcitrant seeds adds an extra layer of difficulty to genetic transformation(Umarani et al.,2015),as most methods rely on seed germination as a basis for transformation. 展开更多
关键词 study gene function krenek plant genetic engineering hairy root transformation fruit trees agrobacterium rhizogenes subtropical fruit trees genetic transformation chinese cabbage li
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Streamlined Agrobacterium rhizogenes-mediated hairy root transformation for efficient CRISPR/Cas9-based gene editing evaluation in diverse Citrullus cultivars
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作者 Yong Zhao Hongju Zhu +7 位作者 Xuqiang Lu Muhammad Anees Nan He Dongdong Yang Zihao Chen Zonglie Hong Junhong Zhang Wenge Liu 《Horticultural Plant Journal》 2025年第2期816-826,共11页
The CRISPR/Cas9 genome-editing system serves as a pivotal tool for enhancing crop genetics.Within this system,single guide RNAs(sgRNAs)are instrumental in the precise cleavage of DNA double strands.However,the efficie... The CRISPR/Cas9 genome-editing system serves as a pivotal tool for enhancing crop genetics.Within this system,single guide RNAs(sgRNAs)are instrumental in the precise cleavage of DNA double strands.However,the efficiency of gene editing varies among sgRNAs,emphasizing the need to meticulously select target sites,especially in the context of Citrullus lanatus,a species notorious for its challenging and inefficient generation of transgenic plants through stable transformation.This study employed an Agrobacterium rhizogenes-mediated hairy root method to assess effective target sites for gene editing of ClCIPK17 across various Citrullus species.Hairy roots were successfully induced in different plant tissues at diverse growth stages of Citrullus lanatus,Citrullus mucosospermus,and Citrullus amarus.Employing a vector with two sgRNAs(sgRNA1 and sgRNA5)positioned within conserved regions of exon 1 and exon 5 of ClCIPK17 in the CRISPR/Cas9 system,targeted mutations were detected in 90.9%of accessions across the four Citrullus species.Notably,73.94%of all examined hairy roots exhibited mutations at the sgRNA1 site,while the sgRNA5 site showed no mutations.Among the 31 different mutation types identified at the sgRNA1 site,base deletion was the most prevalent.Using the sgRNA1 site of ClCIPK17,stable transgenic watermelon buds were obtained from explants,and the targeted mutations of the sgRNA1 site were confirmed.These findings underscore the viability of the hairy root transformation system in assessing the editing efficiency of sgRNA targets in diverse Citrullus species. 展开更多
关键词 Citrullus lanatus sgRNAs Agrobacterium rhizogenes Hairy root transformation CRISPR/Cas9
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Soybean hairy roots produced in vitro by Agrobacterium rhizogenes-mediated transformation 被引量:4
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作者 Li Chen Yupeng Cai +6 位作者 Xiujie Liu Chen Guo Shi Sun Cunxiang Wu Bingjun Jiang Tianfu Han Wensheng Hou 《The Crop Journal》 SCIE CAS CSCD 2018年第2期162-171,共10页
Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agroba... Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agrobacterium rhizogenes-mediated transformation of soybean and the induction of hairy root development in vitro. Cotyledons with 0.5-cm hypocotyls were cut from 5-day-old seedlings and used as explants. After infection and co-cultivation,hairy roots were produced in induction culture medium after 10–12 days. Using this method, 90%–99% of the infected explants of five different cultivars produced hairy roots within one month. Observations using reporter constructs showed that 30%–60% of the hairy roots induced were transformed. Based on high transformation efficiency and short transformation period, this method represents an efficient and rapid platform for study of soybean gene function. 展开更多
关键词 AGROBACTERIUM RHIZOGENES HAIRY root Protocol SOYBEAN transformation
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Effect of Colquhoumia Root on the Expression of Transforming Growth Factor-β in Mesangial Proliferation Glomerulonephritis Model 被引量:4
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作者 曾红兵 常伟 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2005年第4期412-415,共4页
Summary: To study the efficacy and the mechanism of Colquhoumia root ( Tripterygium hypoglaucure (Le,vL) Hutch) in the treatment of mesangial proliferation glomerulonephritis (MsPGN), SD rats were injected with... Summary: To study the efficacy and the mechanism of Colquhoumia root ( Tripterygium hypoglaucure (Le,vL) Hutch) in the treatment of mesangial proliferation glomerulonephritis (MsPGN), SD rats were injected with anti-thymoeyte serum (ATS) to make MsPGN model (anti-Thyl model). The rats were then divided into 3 groups: normal control group, anti-Thyl model group and treatment group. Histopathologieal (HE, PAS), immunohistoehemieal, RT-PCR technique and computer imaging analysis system were used to evaluate mesangial matrix production, the expression of TGF-β protein and mRNA in the tissues of kidney. Our result showed that proteinuria and the ratio of extraeellular matrix/glomerular capillaries area (ECM/CA) were increased significantly in model group. The expression of both TGF-β protein and mRNA in glomeruli was much higher in model group than in control group (P〈0.01). After the treatment with Colquhoumia root, proteinuria, ECM/CA and the expression of both TGF-β1 protein and mRNA in glomeruli were significantly decreased in treatment group as compared with those in model group. It is concluded that Colquhoumia root is effective in reducing proteinuria and mesangial matrix proliferation in MsPGN and it may achieve these effects by inhibiting the expressions of TGF-β1 protein and mRNA of mesangial cells. 展开更多
关键词 mesangial proliferation glomerulonephritis Colquhoumia root tripterygium hypoglaucure (Le vL) Hutch transforming growth faetor-β1
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Fast,simple,efficient Agrobacterium rhizogenes-mediated transformation system to non-heading Chinese cabbage with transgenic roots 被引量:1
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作者 Huiyu Wang Yushan Zheng +3 位作者 Qian Zhou Ying Li Tongkun Liu Xilin Hou 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期450-460,共11页
Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However,the immaturity of its stable transformation system and its low transformation ... Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However,the immaturity of its stable transformation system and its low transformation efficiency limit gene function research on non-heading Chinese cabbage. Agrobacterium rhizogenes-mediated(ARM) transgenic technology is a rapid and effective transformation method that has not yet been established for non-heading Chinese cabbage plants. Here, we optimized conventional ARM approaches(one-step and two-step transformation methods) suitable for living non-heading Chinese cabbage plants in nonsterile environments. Transgenic roots in composite non-heading Chinese cabbage plants were identified using phenotypic detection, fluorescence observation, and PCR analysis. The transformation efficiency of a two-step method on four five-day-old non-heading Chinese cabbage seedlings(Suzhouqing, Huangmeigui, Wuyueman, and Sijiu Caixin) was 43.33%-51.09%, whereas using the stout hypocotyl resulted in a transformation efficiency of 54.88% for the 30-day-old Sijiu Caixin.The one-step method outperformed the two-step method;the transformation efficiency of different varieties was above 60%, and both methods can be used to obtain transgenic roots for functional studies within one month. Finally, optimized ARM transformation methods can easily,quickly, and effectively produce composite non-heading Chinese cabbage plants with transgenic roots, providing a reliable foundation for gene function research and non-heading Chinese cabbage genetic improvement breeding. 展开更多
关键词 Agrobacterium rhizogenes Non-heading Chinese cabbage Transgenic roots Composite plant transformation efficiency
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Optimizing Culture System of Ri T-DNA Transformed Roots for Citrus grandis cv. Changshou Shatian You
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作者 YANG Xiao-hong SUN Zhong-hai TONG Rui-jian 《Agricultural Sciences in China》 CAS CSCD 2006年第2期90-97,共8页
Genetic transformation experiments of the different explants from Citrus grandis cv. Changshou Shatian You infected with Agrobacterium rhizogenes were carried out in darkness or in light. The optimizing culture system... Genetic transformation experiments of the different explants from Citrus grandis cv. Changshou Shatian You infected with Agrobacterium rhizogenes were carried out in darkness or in light. The optimizing culture system of Ri T-DNA transformed roots for C. grandis cv. Changshou Shatian You was constructed as follows: After the ventral wounded striations on the single activation cotyledon were inoculated by A. rhizogenes A4 (logarithmic period), they were cocultured at (25 ±2)℃ in darkness for 25-30 days; some transformed roots were generated from wounded striations of most cotyledons. The genetically transformed ratio is (83 ± 11)%. Axenic Ri T-DNA transformed roots (hairy roots) were harvested after five subcultures. Explants were activated on MT medium. The MS medium was used for subculture of transformed roots. Mass Ri T-DNA transformed roots in which the hormone was produced independently were harvested from this optimizing culture system. White, fresh Ri T-DNA transformed roots were (1.14 ±0.07) cm long, (0.73 ±0.04) mm wide, and the growth direction of transformed roots was negative geotropism. 展开更多
关键词 Citrus grandis cv. Changshou Shatian You Agrobacterium rhizogenes Ri T-DNA transformed root optimizingculture system
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Development of a rapid and efficient system for CR genes identification based on hairy root transformation in Brassicaceae
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作者 Wenlin Yu Lu Yang +12 位作者 Yuanyuan Xiang Rongde Li Xueqing Zhou Longcai Gan Xianyu Xiang Yunyun Zhang Lei Yuan Yanqing Luo Genze Li Youning Wang Yinhua Chen Peng Chen Chunyu Zhang 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第4期1049-1060,共12页
Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars bas... Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars based on mapping and cloning of resistant genes is commonly regarded as the most cost-effective and efficient way to fight against this disease.The traditional way of R gene functional validation requires stable transformation that is both time-and labor-consuming.In this study,a rapid and efficient hairy-root transgenic protocol mediated by Agrobacterium rhizogenes was developed.The transformation positive rate was over 80%in Brassica napus showed by GUS reporter gene and this transformation only took 1/6 of the time compared with stable transformation.The system was applicable to different B.napus varieties and other cruciferous crops including Brassica rapa and Brassica oleracea.In particular,two known CR genes,CRA3.7.1 and CRA8.2.4 were used respectively,as example to show that the system works well for CR gene study combined with subsequent P.brassicae infection in B.napus.Most importantly,it works both in over-expression that led to disease resistance,as well as in RNAi which led to disease susceptible phenotype.Therefore,this system can be used in batch-wise identification of CR genes,and also offered the possibility of manipulating key genes within the P.brassicae genome that could improve our knowledge on host-pathogen interaction. 展开更多
关键词 Brassicaceae Agrobacterium rhizogenes Hairy root transformation CLUBroot Gene function
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Rapid,Efficient and High-Performance Protocol for Agrobacterium rhizogenes-Mediated Hairy Root Transformation of the Common Bean Phaseolus vulgaris
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作者 Sanghamitra Khandual Pallavolu Maheswara Reddy 《Advances in Bioscience and Biotechnology》 2014年第4期333-339,共7页
A rapid, efficient and high-performance transformation protocol employing Agrobacterium rhizogenes was developed for the common bean Phaseolus vulgaris. In this study, we examined competencies of various protocols to ... A rapid, efficient and high-performance transformation protocol employing Agrobacterium rhizogenes was developed for the common bean Phaseolus vulgaris. In this study, we examined competencies of various protocols to induce and explants that respond to hairy root transformation in bean plants. Utilizing young seedlings with severed radicles/hypocotyls, we developed a highly efficient procedure for achieving hairy root transformation frequencies as high as 100% as visualized by GUS reporter gene expression system. Transgenic hairy roots in these young composite plants were susceptible to nodulation by rhizobia, and form an excellent system for high throughput genomic analysis to study root biology and endosymbiosis in common bean. 展开更多
关键词 Phaseolus vulgaris Agrobacterium rhizogenes Hairy root transformation GUS Expression
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基于ISSA-Transformer的电梯制动力矩预测研究
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作者 苏万斌 江叶峰 +2 位作者 李科 周振超 易灿灿 《机电工程》 北大核心 2025年第10期2027-2036,共10页
实现电梯制动器力矩的精确预测对确保电梯安全运行和实现预测性维护具有重要的意义。针对曳引式电梯在制动力矩预测方面存在准确性与可靠性不足的问题,以及现有Transformer存在计算复杂度高和训练时间长的局限性,提出了一种基于改进鲸... 实现电梯制动器力矩的精确预测对确保电梯安全运行和实现预测性维护具有重要的意义。针对曳引式电梯在制动力矩预测方面存在准确性与可靠性不足的问题,以及现有Transformer存在计算复杂度高和训练时间长的局限性,提出了一种基于改进鲸沙虫群算法优化Transformer网络(ISSA-Transformer)的电梯制动力矩预测方法。首先,为了提高Transformer的预测精度,在Transformer模型中添加了特征融合门(FFG)以提高模型的特征提取能力,使其能够更有效地捕捉制动力矩的全局与局部特征;然后,利用拉普拉斯交叉算子、混合对立学习方法以及高斯扰动对鲸沙虫群算法(SSA)进行了改进,以增强SSA的搜索能力和全局最优收敛性。并采用ISSA算法优化了Transformer的迭代次数、批次大小和学习率,以提高模型的计算效率并减少训练时间,从而建立了电梯制动器制动力矩的预测模型;最后,对曳引式电梯制动器数据进行了分析,将所得结果与LSTM、Transformer和SSA-Transformer模型进行了比较。研究结果表明:ISSA-Transformer的均方根误差(RMSE)较LSTM、Transformer和SSA-Transformer模型分别降低了0.0318、0.0144和0.0133,用于电梯制动力矩预测的准确率达到了98.7%,相较传统方法具有更高的精度和稳定性。该方法可为电梯的安全评估和预测性维护提供更可靠的技术支持。 展开更多
关键词 曳引式电梯 升降台 电梯制动器 改进鲸沙虫群算法 transformer网络 特征融合门 均方根误差 长短期记忆网络
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基于DWT的Alpha-Rooting图像增强 被引量:4
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作者 王正友 胡国胜 吴海燕 《小型微型计算机系统》 CSCD 北大核心 2009年第5期996-999,共4页
针对数字图像的频域增强,提出一种基于离散小波变换的Alpha-Rooting图像对比度增强方法.该方法利用小波的多分辨率性质,结合Alpha-Rooting图像对比度增强特点,对高频细节信号采用Alpha-Rooting算法增强,低频近似信号采用归一化增强算法... 针对数字图像的频域增强,提出一种基于离散小波变换的Alpha-Rooting图像对比度增强方法.该方法利用小波的多分辨率性质,结合Alpha-Rooting图像对比度增强特点,对高频细节信号采用Alpha-Rooting算法增强,低频近似信号采用归一化增强算法.实验结果表明,该方法在EME与直方图两个尺度上,优于其他Alpha-Rooting增强算法(DCT、FFT)的对比度增强效果. 展开更多
关键词 离散小波变换 Alpha—rooting 图像增强 EME 直方图
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84K杨组培苗高效毛状根遗传转化体系构建
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作者 焦阳 乔静 +6 位作者 曾智新 王深 杨雪鑫 张英睿 杨玉冰 赵禹森 舒文波 《林业科学》 北大核心 2026年第1期122-132,共11页
【目的】针对药用植物毛状根本源转化困难的技术难题,基于异源转化技术发展潜力,选用速生型84K杨构建高效毛状根遗传转化体系。【方法】本研究以84K杨组培苗为材料,通过比较菌株类型、外植体类型、菌液浓度、侵染时间,构建高效的毛状根... 【目的】针对药用植物毛状根本源转化困难的技术难题,基于异源转化技术发展潜力,选用速生型84K杨构建高效毛状根遗传转化体系。【方法】本研究以84K杨组培苗为材料,通过比较菌株类型、外植体类型、菌液浓度、侵染时间,构建高效的毛状根遗传转化体系。进一步克隆金钗石斛萜类生物碱合成途径下游基因LOC110095726(LOC2),评估异源转化效果。【结果】最佳的诱导菌株是C58C1,21天毛状根诱导率达100%,诱导的平均根数(5.06±2.36)条,平均根长为(12.83±5.75)mm,且转化率为46.67%±11.55%;最佳的诱导外植体是叶片,14天毛状根诱导率达93.33%±11.55%,诱导的平均根数(3.89±2.53)条,平均根长为(8.36±4.24)mm;最佳的侵染浓度是0.8(OD_(600)),21天毛状根诱导率达100%,诱导的平均根数为6.03±2.10条,平均根长为17.77±9.23 mm;最佳的侵染时间是15 min,21天毛状根诱导率达100%,诱导的平均根数为6.03±2.10条,平均根长为17.76±9.23 mm。成功克隆了金钗石斛LOC2基因到过表达载体,并转入发根农杆菌C58C1中,获得了LOC2的阳性毛状根。【结论】84K杨毛状根最佳的遗传转化体系为菌液浓度(OD_(600))0.8的C58C1菌液侵染叶片15 min。这套方法以其简便、快捷、稳定性高等优点,可在药用植物代谢物活性成分功能验证和高活性成分植物创制中应用。该体系不仅适用于代谢途径相似的药用植物活性成分功能验证,也能为规模化生产药用活性成分提供可靠的技术基础。 展开更多
关键词 84K杨 发根农杆菌 毛状根 金钗石斛 遗传转化
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发根农杆菌介导龙葵遗传转化体系优化
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作者 张静静 骆海霞 +1 位作者 洪艳苹 赵世成 《植物研究》 北大核心 2026年第1期111-119,共9页
该研究旨在通过建立发根农杆菌(Agrobacterium rhizogenes)介导的龙葵(Solanum nigrum)遗传转化体系,提高遗传转化效率及总黄酮含量。研究以龙葵叶片为外植体,探究菌株类型、菌液浓度等因素对龙葵毛状根诱导率的影响。基于该体系,构建... 该研究旨在通过建立发根农杆菌(Agrobacterium rhizogenes)介导的龙葵(Solanum nigrum)遗传转化体系,提高遗传转化效率及总黄酮含量。研究以龙葵叶片为外植体,探究菌株类型、菌液浓度等因素对龙葵毛状根诱导率的影响。基于该体系,构建重组质粒PBI121-6flag-SnCHI,通过农杆菌介导,诱导转SnCHI基因的毛状根,考察龙葵毛状根转SnCHI基因后的总黄酮含量变化。研究结果表明:菌株Ar.1193在OD600为1.0、侵染25 min、共培养24 h条件下,龙葵毛状根诱导率可达88.49%。对转SnCHI基因毛状根进行qRT-PCR检测,发现其基因表达水平是空白组的28.81倍;测定转SnCHI基因毛状根的总黄酮含量,发现转SnCHI基因毛状根的总黄酮含量最高达空白组的4.14倍。成功建立龙葵遗传转化体系,对SnCHI基因的功能进行研究,为同属植物的组织培养和遗传转化研究提供参考。 展开更多
关键词 龙葵 毛状根 发根农杆菌 遗传转化体系 黄酮类化合物
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渤海W平台液烃回收系统优化设计及应用
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作者 李仝 代冬冬 +3 位作者 石岩 祁亚轩 李立民 周昊燃 《化工管理》 2026年第3期143-146,共4页
随着油气田不断开发生产,渤海W平台液烃处理量不断增加,W平台现有横竖管液烃回收系统存在液烃回收质量低、自动化程度低,需进一步进行优化提升。基于W平台现有流程基础对原液烃处理系统进行优化设计,实践应用表明,液烃回收系统实现全手... 随着油气田不断开发生产,渤海W平台液烃处理量不断增加,W平台现有横竖管液烃回收系统存在液烃回收质量低、自动化程度低,需进一步进行优化提升。基于W平台现有流程基础对原液烃处理系统进行优化设计,实践应用表明,液烃回收系统实现全手动操作到自动化运行,增收液烃量30 m^(3)/d,液烃外输含水降至0%~0.5%,天然气回收约30×10^(4)m^(3)/a,节省人工时平均6 h/d,落实公司提质增效、绿色低碳、基层减负等相关要求。 展开更多
关键词 海上油田 液烃回收 改造优化 绿色低碳 基层减负
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融合Transformer和LSTM的蓝莓根区土壤含水量预测模型 被引量:4
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作者 王亿 曹姗姗 +3 位作者 孙伟 胡博 古丽米拉·克孜尔别克 孔繁涛 《湖北农业科学》 2024年第8期78-84,共7页
针对土壤含水量预测模型存在难以解决非线性复杂特征、易陷入局部极小值等问题,构建融合Transformer和LSTM的土壤含水量深度学习预测模型(Transformer-LSTM)。采集山东省青岛市黄岛区丁家寨村蓝莓(Vaccinium spp.)生产区冷棚与露天2个... 针对土壤含水量预测模型存在难以解决非线性复杂特征、易陷入局部极小值等问题,构建融合Transformer和LSTM的土壤含水量深度学习预测模型(Transformer-LSTM)。采集山东省青岛市黄岛区丁家寨村蓝莓(Vaccinium spp.)生产区冷棚与露天2个站点的蓝莓根区土壤和气象数据作为建模数据,根据皮尔逊相关性和偏自相关性分析选择模型的数据输入特征与输入长度,与单一的Transformer模型和LSTM模型进行对比分析,评估模型对土壤含水量的预测性能。结果表明,Transformer-LSTM模型在预测精度上均优于单一的Transformer模型和LSTM模型,Transformer-LSTM模型的平均绝对误差(MAE)、均方根误差(RMSE)、平均绝对百分比误差(MAPE)、决定系数(R^(2))分别为0.245 9、0.572 0、0.012 1、0.960 6。Transformer-LSTM模型可以更全面地提取蓝莓种植环境因子输入序列中的特征信息,有效提升土壤含水量因子预测精度和水平。 展开更多
关键词 蓝莓(Vaccinium spp.) 根区土壤 含水量 transformER LSTM 预测模型
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THE WEIGHTED KATO SQUARE ROOT PROBLEMOF ELLIPTIC OPERATORS HAVING A BMOANTI-SYMMETRICPART
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作者 马文贤 杨四辈 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期532-550,共19页
Let n≥2 and let L be a second-order elliptic operator of divergence form with coefficients consisting of both an elliptic symmetric part and a BMO anti-symmetric part in ℝ^(n).In this article,we consider the weighted... Let n≥2 and let L be a second-order elliptic operator of divergence form with coefficients consisting of both an elliptic symmetric part and a BMO anti-symmetric part in ℝ^(n).In this article,we consider the weighted Kato square root problem for L.More precisely,we prove that the square root L^(1/2)satisfies the weighted L^(p)estimates||L^(1/2)(f)||L_(ω)^p(R^(n))≤C||■f||L_(ω)^p(R^(n);R^(n))for any p∈(1,∞)andω∈Ap(ℝ^(n))(the class of Muckenhoupt weights),and that||■f||L_(ω)^p(R^(n);R^(n))≤C||L^(1/2)(f)||L_(ω)^p(R^(n))for any p∈(1,2+ε)andω∈Ap(ℝ^(n))∩RH_(2+ε/p),(R^(n))(the class of reverse Hölder weights),whereε∈(0,∞)is a constant depending only on n and the operator L,and where(2+ε/p)'denotes the Hölder conjugate exponent of 2+ε/p.Moreover,for any given q∈(2,∞),we give a sufficient condition to obtain that||■f||L_(ω)^p(R^(n);R^(n))≤C||L^(1/2)(f)||L_(ω)^p(R^(n))for any p∈(1,q)andω∈A_(p)(R^(n))∩pRH_(q/p),(R^(n)).As an application,we prove that when the coefficient matrix A that appears in L satisfies the small BMO condition,the Riesz transform∇L^(−1/2)is bounded on L_(ω)^(p)(ℝ^(n))for any given p∈(1,∞)andω∈Ap(ℝ^(n)).Furthermore,applications to the weighted L^(2)-regularity problem with the Dirichlet or the Neumann boundary condition are also given. 展开更多
关键词 elliptic operator Kato square root problem Muckenhoupt weight Riesz transform reverse Hölder inequality
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注意力适配:数字技术驱动下基层行政负担的治理转化——基于江苏Z村数字积分运行的实证考察 被引量:5
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作者 金华 董冉 《中共天津市委党校学报》 北大核心 2025年第1期74-84,共11页
随着大数据、人工智能的加速迭代和应用落地,数字技术被视为解构基层行政负担、提升行政效能的重要手段。领导注意力以不同的分配策略牵引数字技术的作用方向,数字技术通过纵向压力传导、横向资源竞争、内部行动路线细化加剧基层行政负... 随着大数据、人工智能的加速迭代和应用落地,数字技术被视为解构基层行政负担、提升行政效能的重要手段。领导注意力以不同的分配策略牵引数字技术的作用方向,数字技术通过纵向压力传导、横向资源竞争、内部行动路线细化加剧基层行政负担。基层行政负担呈现三种基本样态,即技术性负担、制度性负担与互动性负担。技术性负担源自注意力错位与技术认知失调引发的目标偏差,制度性负担源自注意力短视与制度不稳定性引发的价值偏差,互动性负担源自注意力失衡与利益竞争引发的跨部门协同乏力。科学、合理地运用数字技术化解基层行政负担,要明确领导注意力分配限度,建立差异化分配机制;构建数字治理规则,推进注意力与数字治理的平衡;完善数字治理的配套制度,厘清各级权责体系;建立科学的考评体系,推进基层行政负担实质性减轻。 展开更多
关键词 数字技术 基层行政负担 注意力分配 数字化转型
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无限维复向量空间上代数线性变换的根
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作者 王涵 赵静 刘合国 《海南大学学报(自然科学版中英文)》 2025年第4期455-462,共8页
设F是一个域,V是F上的一个向量空间,α是V上的一个线性变换,m是一个大于1的正整数。若V上的线性变换χ满足χ^(m)=α,则称χ是α的一个m次根。借助主理想整环上有界模的Prüfer-Baer定理,研究无限维复向量空间上代数线性变换,给出... 设F是一个域,V是F上的一个向量空间,α是V上的一个线性变换,m是一个大于1的正整数。若V上的线性变换χ满足χ^(m)=α,则称χ是α的一个m次根。借助主理想整环上有界模的Prüfer-Baer定理,研究无限维复向量空间上代数线性变换,给出了α的一个m次根可表示为α的多项式的局部条件和整体条件,所得结果深化了矩阵分析里的相关内容。 展开更多
关键词 Prüfer-Baer定理 线性变换 中国剩余定理
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试论东巴史诗的地位与影响
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作者 杨杰宏 《文山学院学报》 2025年第3期20-26,共7页
纳西族拥有创世史诗《创世纪》、英雄史诗《黑白战争》两大史诗,因两部史诗都是由东巴象形文字所书写记载,并由东巴祭司在东巴仪式上演述,所以又称为东巴史诗。东巴史诗以其富有想象力的语言艺术讲述了众多的神话故事,塑造了成百上千的... 纳西族拥有创世史诗《创世纪》、英雄史诗《黑白战争》两大史诗,因两部史诗都是由东巴象形文字所书写记载,并由东巴祭司在东巴仪式上演述,所以又称为东巴史诗。东巴史诗以其富有想象力的语言艺术讲述了众多的神话故事,塑造了成百上千的文学形象,型塑了纳西族的世界观、宇宙观、价值观、人生观,成为纳西族的文化基因、历史根谱。东巴史诗在东巴文学体系中占有着重要的地位,被称为“东巴文学的扛鼎之作”。东巴史诗是纳西族代表性的传统经典,被列入中华绝学之列,并入选世界记忆遗产名录,成为国家“非遗”项目。就社会价值及影响而言,东巴史诗在丰富纳西族文学,提高丽江知名度、推动丽江文化旅游、文化产业发展,促进社会和谐,社区建设等方面发挥着越来越重要的作用。 展开更多
关键词 东巴史诗 历史根谱 创造性转化 当代价值
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棉花发根农杆菌转化体系的建立及生根优化 被引量:3
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作者 汪炜檬 魏云晓 +4 位作者 唐云霓 刘苗苗 陈全家 邓晓娟 张锐 《中国农业科学》 北大核心 2025年第8期1479-1493,共15页
【背景】棉花是全球最主要的农作物之一,生物工程技术应用极大地提高了分子育种的效率,但棉花遗传转化目前存在受基因型限制、时间长和转化方法单一等问题。【目的】建立由发根农杆菌(Agrobacterium rhizogenes)介导的高效棉花遗传转化... 【背景】棉花是全球最主要的农作物之一,生物工程技术应用极大地提高了分子育种的效率,但棉花遗传转化目前存在受基因型限制、时间长和转化方法单一等问题。【目的】建立由发根农杆菌(Agrobacterium rhizogenes)介导的高效棉花遗传转化体系,丰富棉花遗传育种方法。【方法】以常用的棉花受体WC和R18为主要试验材料,利用mRUBY作为报告基因,通过诱导生根的激素组合和浓度的筛选优化、不同外植体和不同基因型棉花生根体系差异分析来对发根农杆菌介导的生根过程进行优化,在此基础上建立稳定的遗传转化体系,并将该体系应用于基因编辑。【结果】在生根培养基(RIM)中添加萘乙酸(naphthaleneacetic acid,NAA)和洛伐他汀(lovastatin)比单独添加NAA,或添加NAA+吲哚-3-丁酸(indole-3-butyric acid,IBA)、NAA+Lovastatin+IBA更易生根,进一步筛选出最适合诱导出毛状根的萘乙酸和洛伐他汀浓度均为2 mg·L^(-1)。子叶是最易诱导生根的外植体,WC子叶、子叶节和下胚轴单位材料的生根效率分别为398%、72%和39%,且子叶诱导生根时间最短(7 d),比子叶节至少短3 d,比下胚轴至少短8 d;R18最适合诱导生根的外植体也是子叶,但生根数量存在差异。基因型比较表明WC、R18、农大棉8号(NDM8)、新陆早61号(XLZ61)、Gb-1和Gb-2每片子叶在侵染后20 d的生根效率分别为398%、116%、199%、103%、57%和0,陆地棉的生根效率均在100%以上,海岛棉在100%以下,其中Gb-2在侵染后35 d才开始生根,陆地棉中常用的受体品种又表现出生根效率略高于生产品种的趋势。遗传转化的阳性率与生根率之间存在一定的差异,侵染后20 d NDM8、XLZ61、Gb-1和Gb-2的转化阳性率依次为59.8%、16.0%、38.5%和0。此外,以获得的阳性根作为后续试验的外植体,进行非胚性愈伤和胚性愈伤诱导,获得了转mRUBY植株,建立了完整的遗传转化体系,且发现植株颜色深浅和mRUBY表达量成正相关;同时获得了GhGI被编辑的棉花植株。【结论】优化了发根农杆菌介导的棉花生根过程,并建立了棉花遗传转化体系,同时成功将该体系应用于基因编辑,获得了转mRUBY和转GhGI的棉花植株。 展开更多
关键词 棉花 遗传转化 发根农杆菌 毛状根 基因编辑
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