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Timing of N Application Affects Net Primary Production of Soybean with Different Planting Densities

Journal of Integrative Agriculture 2014年第12期13卷 2778-2787页

作者： ZHANG Ming-cong sun wen-xiang LIU Yuan-ying LUO Sheng-guo ZHAO Jing WU Qiong WU Zhen-yu JIANG Yi Resource and Environment College Northeast Agricultural University

Understanding the relationship between the timing of N fertilizer applications and crop primary production is crucial for achieving high yield and N use efifciency in agriculture. This study investigated the effects of starting-N plus topdressing N applications （as compared to the common practice of all basal application） on soybean photosynthetic capacity under different planting densities. A ifeld experiment was conducted in two growing seasons （2011 and 2012）, and the soybean （Glycine max L. Merrill） cultivar was Dongnong 52, three planting densities （20, 25 and 30 plants m-2）, and four N fertilizer application patterns （all N fertilizer of 6 g N m-2 as basal fertilizer, all N fertilizer as topdressing at beginning pod stage （R3）, 1.8 g N m-2 as basal fertilizer and 4.2 g N m-2 as topdressing at stage R3 and full pod stage （R4）, respectively）. The results indicated that under the same planting density, compared to applying all N as basal fertilizer, the application of starter-N plus topdressing N substantially reduced the rate of pod abscission, and enhanced leaf area index （LAI） signiifcantly at beginning seed stage （R5）（P〈0.05）, net assimilation rate （NAR） during stages R4-full seed stage （R6）（P〈0.05）, contribution rate of post-seed iflling assimilate to seed （CPA）（P〈0.05）, and yield （P〈0.05）. Applying topdressing N at stage R4 resulted in higher net primary production and yield than applying topdressing N at stage R3. When applying starter-N plus topdressing N at planting density of 25 plants m-2, LAI after stage R5 and NAR after stage R4 were increased by 5.92-16.3%（P〈0.05） and 13.7-26.6%（P〈0.05） with the planting density of 20 plants m-2, respectively, and yield was 8.46-14.0%（P〈0.05） higher than that under 20 plants m-2. When planting density increased to 30 plants m-2, only LAI during stages R4-R5 and NAR during stages R4-R5 increased by applying starter-N plus topdressing N, while the other indexes declined. Overall, results of this study demonstrated

关键词： soybean starter-N plus topdressing N density leaf area index (LAI) net assimilation rate (NAR)

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跨国公司对华技术转移的理论思考——基于本土企业技术创新能力提升的分析框架

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中国软科学 2005年第4期 112-119页

作者：彭纪生孙文祥南京大学工程管理学院江苏南京210093

本文通过对 1960年代以来国内外理论和实证研究学术文献的研究发现,,跨国公司技术转移对东道国技术进步的影响是不确定的。原因是对技术转移理解标准不一,缺乏基于技术转移实现过程的深入分析。本文以本土企业创新能力提升为指向,提出... 详细信息

本文通过对 1960年代以来国内外理论和实证研究学术文献的研究发现,,跨国公司技术转移对东道国技术进步的影响是不确定的。原因是对技术转移理解标准不一,缺乏基于技术转移实现过程的深入分析。本文以本土企业创新能力提升为指向,提出技术转移实现的不同层次划分和相应的评价标准,并提出研究该问题的新的分析框架。

关键词：跨国公司技术转移本土企业技术创新能力

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用于电力系统谐波频率高分辨估计的MUSIC算法

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电测与仪表 2008年第10期45卷 19-21,32页

作者：孙向文孙立功河南科技大学电子信息工程学院河南洛阳471039

指出了目前电力系统谐波频率常规估计算法的诸多不足,将基于多重信号分类(MUSIC)的高分辨谐波频率估计算法引进电力系统谐波频率估计领域。给出了MUSIC算法的基本原理,对MUSIC算法的频谱分辨能力和频率检测门限进行了理论分析,在Matlab... 详细信息

指出了目前电力系统谐波频率常规估计算法的诸多不足,将基于多重信号分类(MUSIC)的高分辨谐波频率估计算法引进电力系统谐波频率估计领域。给出了MUSIC算法的基本原理,对MUSIC算法的频谱分辨能力和频率检测门限进行了理论分析,在Matlab仿真平台下对MUSIC算法和FFT算法的频率估计性能进行了比较。理论分析和Matlab仿真结果表明,MUSIC频率估计算法对数据量要求较低,具有良好的分辨特性和抗噪声能力,且能够检测微弱的谐波信号。

关键词：谐波频率 FFT频率估计 MUSIC算法

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Real-world evidence on the efficacy and safety of vonoprazanamoxicillin dual therapy for Helicobacter pylori treatment in elderly patients

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World Journal of Gastroenterology 2025年第1期31卷 68-78页

作者： wen Gao Jing-wen Li Hui Ye Xue-Zhi Zhang Jian-xiang Liu Hong Cheng Department of Gastroenterology Peking University First HospitalBeijing 100034China School of Medicine Tsinghua MedicineTsinghua UniversityBeijing 100034China Department of Traditional Chinese Medicine and Integrative Medicine Peking University First HospitalBeijing 100034China

BACKGROUND A dual therapy regimen containing amoxicillin is a common treatment option for the eradication of Helicobacter pylori(***).While substantial research supports the efficacy and safety of vonoprazan and amoxicillin(VA)dual therapy in the general population,there is still a lack of studies specifically focusing on its safety in elderly *** To evaluate efficacy and safety of VA dual therapy as first-line or rescue treatment for *** in elderly *** As a real-world retrospective study,data were collected from elderly patients aged 60 years and above who accepted VA dual therapy(vonoprazan 20 mg twice daily+amoxicillin 1000 mg thrice daily for 14 days)for *** eradication in the Department of Gastroenterology at Peking University First Hospital between June 2020 and January *** status was evaluated by^(13)C-urease breath test 6 weeks after *** adverse events(AEs)during treatment were *** In total,401 cases were ***-one cases were excluded due to loss to follow-up,lack of re-examination,or unwillingness to take *** total of 380 included cases comprised 250 who received VA dual therapy as first-line treatment and 130 who received VA dual therapy as rescue *** was successfully eradicated in 239 cases(95.6%)in the first-line treatment group and 116 cases(89.2%)in the rescue treatment *** overall incidence of AEs was 9.5%for both ***,9.2%of patients experienced an AE in the first-line treatment group and 10.0%in the rescue treatment *** patients discontinued treatment due to AE,with a discontinuation rate of 1.3%.No serious AE *** The VA dual therapy regimen as a first-line treatment and a rescue therapy was effective and safe for elderly patients aged 60 and older.

关键词： Helicobacter pylori Vonoprazan Amoxicillin Dual therapy Elderly

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利用教育券实现义务教育公平与效率的探索

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山西师大学报（社会科学版） 2008年第3期35卷 120-124页

作者：鹿茸孙文祥江苏职工医科大学实习医院南京210057 南京审计学院管理学院南京210039

义务教育的本质属性决定了其对公平和效率要求的内在统一。针对我国面前义务教育中存在的公平与效率问题,基于教育券的基本理念设计的义务教育资源配置机制,创造性地引入学生的折算比率和学校的兑换比率,实现义务教育中的学生公平和校... 详细信息

义务教育的本质属性决定了其对公平和效率要求的内在统一。针对我国面前义务教育中存在的公平与效率问题,基于教育券的基本理念设计的义务教育资源配置机制,创造性地引入学生的折算比率和学校的兑换比率,实现义务教育中的学生公平和校际公平,并通过强化学校间的良性竞争,保证了义务教育效率的提高,是当前教育改革中一种可行性的政策选择。

关键词：教育券义务教育公平效率

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