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Host-induced silencing of MpPar6 confers Myzus persicae resistance in transgenic rape plants 被引量:1
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作者 Qi Zhang Wenqin Zhan +3 位作者 Chao Li Ling Chang Yi Dong Jiang Zhang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期187-194,共8页
Plant-mediated RNA interference(RNAi)has emerged as a promising technology for insect control.The green peach aphid,Myzus persicae,feeds on over 400 species of host plants.Brassica napus(rape)is the second most import... Plant-mediated RNA interference(RNAi)has emerged as a promising technology for insect control.The green peach aphid,Myzus persicae,feeds on over 400 species of host plants.Brassica napus(rape)is the second most important oilseed crop worldwide.Myzus persicae is highly reproductive and causes severe damage to the rape plants due to its quite flexible life cycle.In this study,we tested the RNAi effects of transgenic rape plants on M.persicae.By in vitro feeding M.persicae with artificial diets containing double-stranded RNAs(dsRNAs)targeting seven aphid genes,we identified a new gene encoding the partitioning-defective protein 6(Par6)as the most potent RNAi target.Tissue-and stage-expression analysis of Par6 suggested this gene is highly expressed in the embryo and adult stage of M.persicae.We next generated transgenic rape plants expressing ds Par6 by Agrobacteriummediated transformation and obtained nine independent transgenic lines.Compared to wild-type control plants,transgenic rape lines expressing ds Par6 showed strong resistance to M.persicae.Feeding assays revealed that feeding transgenic rape plants to M.persicae significantly decreased MpPar6 expression and survival rate and impaired fecundity.Furthermore,we showed that the resistance levels to M.persicae are positively correlated with ds Par6 expression levels in transgenic rape plants.Our study demonstrates that transgenic rape plants expressing ds Par6 are efficiently protected from M.persicae.Interfering with the genes involved in embryo development could be the effective RNAi targets for controlling aphids and potentially other insect pests. 展开更多
关键词 oilseed rape pest control APHID double-stranded RNA RNA interference
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Strategies and Economic Benefit Analysis for Productive Landscape of Rape Flower Sea in Cold Regions
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作者 Zhang Jiaxin Wu Zhiheng +2 位作者 Zhu Xuanbo Pan Shengkai Yan Yongqing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第2期34-42,共9页
The cold regions are located in high latitudes and cold climates.The local excellent ornamental plant resources are relatively scarce.The plant species that are suitable for both ornamental and productive benefits of ... The cold regions are located in high latitudes and cold climates.The local excellent ornamental plant resources are relatively scarce.The plant species that are suitable for both ornamental and productive benefits of landscape of flower sea construction are also even fewer.Therefore,it is imperative to introduce and screen the plant resources suitable for cold regions to create the landscape of flower sea.The rape,an oilseed crop,was used as a research object in order to create a productive flower landscape with both ornamental and economic values in cold regions.Four rape flower varieties,Qingza No.5,7,9,and 11,were introduced from Qinghai Hufeng Agricultural Science and Technology Group Co.,Ltd.They were planted in the experimental practice base of Northeast Agricultural University in three batches.Development characteristics and seed yield of rape flowers on different sowing dates were studied.The fuzzy probability method was used to comprehensively evaluate the varieties.The results showed that the rape flowers grew well in Harbin City during the experimental sowing period,which could form a good landscape of flower sea and had a considerable rapeseed yield.It could be widely used in cold urban and rural areas,such as Harbin City.In view of the experimental results,the strategies of creating a productive landscape of rape flower sea were proposed and the economic benefits were analyzed.It could change the status quo of a uniform landscape of flower sea in cold regions,help the development of rural tourism,and promote local economic income. 展开更多
关键词 rape flower sea productive landscape cold region landscape construction economic benefit
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Different Foliar Fertilizer Treatments Affect the Yield and Quality of Brassica napus L.for Both Vegetable and Oil Dual-Use Rape
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作者 CHU Bai-feng LI Gang +2 位作者 LIU Wen-xiang YI Rui-peng ZHANG Wei 《Agricultural Science & Technology》 CAS 2024年第2期1-6,共6页
Field experiments were carried out to study the effect of different foliar fertilizer treatments on the agronomic traits,yield,and quality of Brassica napus L.for both vegetable and oil dual-use rape.The seedlings of... Field experiments were carried out to study the effect of different foliar fertilizer treatments on the agronomic traits,yield,and quality of Brassica napus L.for both vegetable and oil dual-use rape.The seedlings of‘Youtai 929’,‘Jinyoutai 1’,and‘Zhongshuang 11’were sprayed with potassium dihydrogen phosphate,naphthylacetic acid,and selenium fertilizer,and the agronomic traits,yield,and quality were determined.The results showed that the naphthylacetic acid treatment had the highest indexes before winter,followed by the selenium fertilizer treatment.At the harvesting stage,the plant height,number of siliquae,yield per plant,and number of effective branches on the main stem of the three varieties were the highest in the naphthylacetic acid treatment,followed by those in the potassium dihydrogen phosphate treatment.The fresh shoot quality was the best in the selenium fertilizer treatment and the second in the naphthylacetic acid treatment.‘Jinyoutai 1’applied with naphthylacetic acid had the highest economic benefit of 4971.78 CNY/667m^(2),which was 642.32 CNY/667m^(2) higher than that of the control.The findings suggested that naphthylacetic acid was suitable to be used as the foliar fertilizer for the seedlings of B.napus varieties for both vegetable and oilseed,and the additional application of selenium fertilizer demonstrated better effect. 展开更多
关键词 ‘Jinyoutai 1’ Vegetable and oil dual-use rape Naphthylacetic acid Selenium fertilizer
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Genome-wide and candidate gene association studies identify BnPAP17 as conferring the utilization of organic phosphorus in oilseed rape
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作者 Ping Xu Hao Li +6 位作者 Haiyuan Li Ge Zhao Shengjie Dai Xiaoyu Cui Zhenning Liu Lei Shi Xiaohua Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1134-1149,共16页
Phosphorus(P)is essential for living plants,and P deficiency is one of the key factors limiting the yield in rapeseed production worldwide.As the most important organ for plants,root morphology traits(RMTs)play a key ... Phosphorus(P)is essential for living plants,and P deficiency is one of the key factors limiting the yield in rapeseed production worldwide.As the most important organ for plants,root morphology traits(RMTs)play a key role in P absorption.To investigate the genetic variability of RMT under low P availability,we dissected the genetic structure of RMTs by genome-wide association studies(GWAS),linkage mapping and candidate gene association studies(CGAS).A total of 52 suggestive loci were associated with RMTs under P stress conditions in 405 oilseed rape accessions.The purple acid phosphatase gene BnPAP17 was found to control the lateral root number(LRN)and root dry weight(RDW)under low P stress.The expression of BnPAP17 was increased in shoot tissue in P-efficient cultivars compared to root tissue and P-inefficient cultivars in response to low P stress.Moreover,the haplotype of BnPAP17^(Hap3)was detected for the selective breeding of P efficiency in oilseed rape.Over-expression of the BnPAP17^(Hap3)could promote the shoot and root growth with enhanced tolerance to low P stress and organic phosphorus(Po)utilization in oilseed rape.Collectively,these findings increase our understanding of the mechanisms underlying BnPAP17-mediated low P stress tolerance in oilseed rape. 展开更多
关键词 genome-wide association studies(GWAS) root morphology traits(RMTs) organic phosphorus(Po) oilseed rape BnPAP17
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Rape Breeding and Its Intellectual Property Protection in China 被引量:6
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作者 Li GAO Leying WU +3 位作者 Yamin PENG Yuanpeng SUN Jin ZENG Zhiguo SUN 《Agricultural Biotechnology》 CAS 2023年第3期23-30,共8页
Rape is the third largest oil crop in the world and the first one in China.The national average rapeseed yield is only 2077.5 kg/hm^(2),and the rapeseed oil yield is 894 kg/hm^(2).This paper introduced the main types,... Rape is the third largest oil crop in the world and the first one in China.The national average rapeseed yield is only 2077.5 kg/hm^(2),and the rapeseed oil yield is 894 kg/hm^(2).This paper introduced the main types,germplasm resources,breeding bases and breeding progress of Chinese rape,and studied its high-quality varieties,breeding patents and new varieties of agricultural plants.We analyzed the main problems such as serious loss of germplasm resources in Brassica campestris L.and Brassica juncea(L.)Czern.et Coss and weak"agricultural chip"in rape field,and put forward strategies such as strengthening the protection of rape germplasm resources,encouraging the development of"agricultural chip"in rape industry clusters with national advantages and characteristics,and strengthening the protection of agricultural intellectual property rights. 展开更多
关键词 rape rapeSEED rape breeding Intellectual property rights Edible oil supply safety China
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Geographical Indication Intellectual Property Protection and Regional Public Brand Construction of Rape Industry in China 被引量:7
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作者 Li GAO Yamin PENG +3 位作者 Leying WU Jin ZENG Yuanpeng SUN Zhiguo SUN 《Asian Agricultural Research》 2023年第6期7-13,共7页
As China s largest oil crop,rape occupies a central position in ensuring the safety of China s cooking oil supply.This paper introduced China s rapeseed industry from the rape type,rapeseed production,planting area,na... As China s largest oil crop,rape occupies a central position in ensuring the safety of China s cooking oil supply.This paper introduced China s rapeseed industry from the rape type,rapeseed production,planting area,national rapeseed production protected area,rape national dominant characteristic industrial clusters,and rapeseed industry,etc.Besides,from the aspects of geographical indication products,geographical indication trademarks,and geographical indications of agricultural products,this paper discussed the intellectual property protection of geographical indications of rape,rapeseed,and rapeseed oil in China.It analyzed the main problems such as the lag in the formulation of relevant standards for geographical indications and the low use of special signs for geographical indications,and finally came up with recommendations including building a public brand of geographical indications and expanding foreign exchanges of geographical indications. 展开更多
关键词 rape rapeSEED rapeseed oil Geographical indication Regional public brand China
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American glabrous rice utilized in breeding of super-high-yielding and good-quality varieties 被引量:2
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作者 LUO Ju Hu Peisong TANG Shaoqing,and HUANG Fasong,CNRRI,Hangzhou 310006,China 《Chinese Rice Research Newsletter》 2000年第2期3-5,共3页
The yield potential of current rice varieties has reached a high plateau and fluc-tuated within a narrow range. Based on the theory and practice of rice breedingfor super-high-yield, we put forward a concept of "... The yield potential of current rice varieties has reached a high plateau and fluc-tuated within a narrow range. Based on the theory and practice of rice breedingfor super-high-yield, we put forward a concept of " Two high and one early",which means high biomass and high efficiency of light energy conversion, as wellas fast growing in the early growth stage. The agronomic characters of 15 U. S 展开更多
关键词 HIGH American glabrous rice utilized in breeding of super-high-yielding and good-quality varieties
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National Protection Zone for Rapeseed Production and Industrial Cluster of Rape in Hubei Province 被引量:5
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作者 Li GAO Yamin PENG +3 位作者 Leying WU Jin ZENG Yuanpeng SUN Zhiguo SUN 《Asian Agricultural Research》 2023年第9期1-10,共10页
Hubei Province is the main winter rapeseed producing area in China,and has the national advantage and characteristic industrial cluster of rape.The protection zone for the production of important agricultural products... Hubei Province is the main winter rapeseed producing area in China,and has the national advantage and characteristic industrial cluster of rape.The protection zone for the production of important agricultural products of rapeseed in Hubei Province also ranks first as that in Hunan Province.This paper studied the winter rape industry,the important agricultural product production protection zone of rapeseed,the provincial double-low high-quality rape protection zone and the industrial cluster of rape in Jianghan Plain in Hubei Province,and analyzed the main problems existing in the development of rapeseed production protection zone and industrial cluster of rape.Finally,it came up with strategies including promoting national rape varieties,overcoming the problem of rape"agricultural chip",promoting the"rice+rape"rotation model,and strengthening the protection of intellectual property rights of brand marks. 展开更多
关键词 Winter rape rapeSEED Protection zone for the production of important agricultural products National advantageous characteristic industrial cluster Hubei Province
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Biotechnology ofα-linolenic acid in oilseed rape(Brassica napus)using FAD2 and FAD3 from chia(Salvia hispanica)
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作者 XUE Yu-fei Inkabanga Tseke ALAIN +7 位作者 YIN Neng-wen JIANG Jia-yi ZHAO Yan-ping LU Kun LI Jia-na DING Yan-song ZHANG Shi-qing CHAI You-rong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第12期3810-3815,共6页
α-Linolenic acid(ALA,18:3Δ9,12,15)is an essential fatty acid for humans since it is the precursor for the biosynthesis of omega-3 long-chain polyunsaturated fatty acids(LC-PUFA).Modern people generally suffer from d... α-Linolenic acid(ALA,18:3Δ9,12,15)is an essential fatty acid for humans since it is the precursor for the biosynthesis of omega-3 long-chain polyunsaturated fatty acids(LC-PUFA).Modern people generally suffer from deficiency of ALA because most staple food oils are low or lack ALA content.Biotechnological enrichment of ALA in staple oil crops is a promising strategy.Chia(Salvia hispanica)has the highest ALA content in its seed oil among known oil crops.In this study,the FAD2 and FAD3 genes from chia were engineered into a staple oil crop,oilseed rape(Brassica napus),via Agrobaterium tumefaciens-mediated transformation of their LP4-2A fusion gene construct driven by the seed-specific promoter P_(NapA).In seeds of T0,T1,and T2 lines,the average ALA contents were 20.86,23.54,and 24.92%,respectively,which were 2.21,2.68,and 3.03 folds of the non-transformed controls(9.42,8.78,and 8.22%),respectively.The highest seed ALA levels of T0,T1,and T2 plants were 38.41,35.98,and 39.19%respectively,which were 4.10-4.77 folds of the respective controls.FA-pathway enzyme genes(BnACCD,BnFATA,BnSAD,BnSCD,BnDGAT1,BnDGAT2,and BnDGAT3)and positive regulatory genes(BnWRI1,BnLEC1,BnL1L,BnLEC2,BnABI3,BnbZIP67,and BnMYB96)were all significantly up-regulated.In contrast,BnTT1,BnTT2,BnTT8,BnTT16,BnTTG1,and BnTTG2,encoding negative oil accumulation regulators but positive secondary metabolism regulators,were all significantly down-regulated.This means the foreign ShFAD2-ShFAD3 fusion gene,directly and indirectly,remodeled both positive and negative loci of the whole FA-related network in transgenic B.napus seeds. 展开更多
关键词 BIOTECHNOLOGY α-linolenic acid oilseed rape(Brassica napus) FAD2 FAD3 chia(Salvia hispanica)
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An Artificial Approach for the Fractional Order Rape and Its Control Model
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作者 Wajaree Weera Zulqurnain Sabir +4 位作者 Muhammad Asif Zahoor Raja Salem Ben Said Maria Emilia Camargo Chantapish Zamart Thongchai Botmart 《Computers, Materials & Continua》 SCIE EI 2023年第2期3421-3438,共18页
The current investigations provide the solutions of the nonlinear fractional order mathematical rape and its controlmodel using the strength of artificial neural networks(ANNs)along with the Levenberg-Marquardt backpr... The current investigations provide the solutions of the nonlinear fractional order mathematical rape and its controlmodel using the strength of artificial neural networks(ANNs)along with the Levenberg-Marquardt backpropagation approach(LMBA),i.e.,artificial neural networks-Levenberg-Marquardt backpropagation approach(ANNs-LMBA).The fractional order investigations have been presented to find more realistic results of the mathematical form of the rape and its control model.The differential mathematical form of the nonlinear fractional order mathematical rape and its control model has six classes:susceptible native girls,infected immature girls,susceptible knowledgeable girls,infected knowledgeable girls,susceptible rapist population and infective rapist population.The rape and its control differential system using three different fractional order values is authenticated to perform the correctness of ANNs-LMBA.The data is used to present the rape and its control differential system is designated as 70%for training,14%for authorization and 16%for testing.The obtained performances of the ANNs-LMBA are compared with the dataset of the Adams-Bashforth-Moulton scheme.To substantiate the consistency,aptitude,validity,exactness,and capability of the LMBA neural networks,the obtained numerical values are provided using the state transitions(STs),correlation,regression,mean square error(MSE)and error histograms(EHs). 展开更多
关键词 rape and its control differential system neural networks fractional order levenberg-marquardt backpropagation approach reference solutions
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基于YOLO v5的直播油菜激光间苗系统设计与试验 被引量:1
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作者 张昌松 李伟 《农业机械学报》 EI CAS CSCD 北大核心 2024年第4期40-52,共13页
间苗是保证直播油菜增产的一项关键技术措施,为解决人工间苗劳动强度大、机械间苗不精确的问题,采用机器视觉的方式,基于深度学习算法YOLO v5平台,设计并搭建自动间苗装置。机器视觉系统评估幼苗种群的合理密植情况,间苗算法以间距和幼... 间苗是保证直播油菜增产的一项关键技术措施,为解决人工间苗劳动强度大、机械间苗不精确的问题,采用机器视觉的方式,基于深度学习算法YOLO v5平台,设计并搭建自动间苗装置。机器视觉系统评估幼苗种群的合理密植情况,间苗算法以间距和幼苗叶展为评估标准,实现控制幼苗间距和筛选优质苗的功能。选用遗传算法对间苗行进路径进行规划,相较于未规划路径可缩短最低为50%的行进距离,最终采用激光器高温烧除的方式完成间苗作业。选取油菜苗作为试验材料,间苗阈值α是划定幼苗最小间距的参数,设置不同的间苗阈值α进行试验。结果表明,间除苗的数量随着间苗阈值α的增加而增加,幼苗平均密度下降的同时种群分布趋于均匀,对间除苗的叶展长度分类统计,α为0~75 mm时,间除苗叶展长度全部在0~20 mm范围;α为75~200 mm时,间除苗叶展长度为0~40 mm,其中叶展长度为20~40 mm的最高占比约为76%;α为200~350 mm时,间除苗叶展长度在40 mm以上的幼苗开始增加,最高占比约为14%,间除苗叶展长度梯次分布证明了间苗算法具备筛选优质苗的性能。间苗执行阶段耗时占据间苗作业总耗时的90%以上,以激光走线参数L、激光器功率P、间苗距离阈值为试验因素,三因素三水平正交试验结果表明:选择合适的激光走线参数L能有效提高间苗死亡率、降低间苗误伤率和减少间苗耗时,在参数L为30 mm、P为7.5 W、α为250 mm下开展土槽台架性能验证试验,激光间苗平均死亡率为93.29%,平均误伤率为5.19%,平均总耗时为15.19 min,为开发基于机器视觉的激光自动间苗机提供了理论基础和技术支撑。 展开更多
关键词 油菜 自动间苗 YOLO v5 激光器 遗传算法
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四川盆区油菜花期低温阴雨灾损评估及风险区划 被引量:1
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作者 赵艺 郭翔 +2 位作者 王鑫 杨德胜 王明田 《中国农业气象》 CSCD 2024年第6期629-642,共14页
花期低温阴雨是四川盆区油菜生产的主要气象灾害之一。本研究利用四川盆区1961-2020年101个气象站的逐日气象资料,1983-2000年油菜产量资料和干旱、低温冷害、连阴雨、大风、冰雹灾情资料,筛选花期低温阴雨灾害年份,采用数理统计方法获... 花期低温阴雨是四川盆区油菜生产的主要气象灾害之一。本研究利用四川盆区1961-2020年101个气象站的逐日气象资料,1983-2000年油菜产量资料和干旱、低温冷害、连阴雨、大风、冰雹灾情资料,筛选花期低温阴雨灾害年份,采用数理统计方法获取花期低温阴雨产量灾损率和致灾因子,通过相关性分析确定油菜花期低温阴雨致灾指标,并利用2001-2020年灾情资料进行检验;基于筛选出的低温、连阴雨关键致灾因子,采用回归分析法建立油菜花期低温阴雨灾害损失评估模型,并进行回代和预测检验,分析灾害风险区划和变化趋势。结果表明:(1)日平均气温≤7℃、过程持续天数≥1d是四川盆区油菜花期低温致灾指标,日平均气温≤7℃的负积温和≥3d过程持续降水量共同组成低温阴雨灾害的关键致灾因子;选用2001-2020年油菜花期低温冷害发生情况对指标进行检验,与实际情况相符。(2)选用1983-2000年的气象、产量、灾情数据建立四川盆区油菜花期低温阴雨灾损评估模型,模型对轻度、中度灾害损失评估等级与实际等级相同或相差1级的评估准确率在96%以上;重度、特重评估等级与实际等级相同的准确率为0,与实际等级相差1级的准确率为75%和0。选用2001-2020年油菜花期低温阴雨灾害发生情况对模型检验,与实际情况基本相符。(3)1961-2020年四川盆区油菜花期低温阴雨灾害风险偏高区域主要分布于盆区西南部、南部及东北部,以中-高风险为主;灾害风险偏低的区域集中于盆区西北部及中部,以低-次低风险为主。(4)气候变暖背景下,四川盆区油菜花期低温阴雨灾害高风险区域呈减少趋势,低风险区域呈增加趋势。综上分析,四川盆区油菜花期低温冷害指标结果可靠,低温阴雨灾损评估模型能够较好地评估灾害损失,可应用于农业气象业务服务;灾害风险区划结果可为四川油菜生产布局提供参考依据。 展开更多
关键词 四川盆区 油菜花期 低温阴雨 灾损评估 风险区划
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Maternal-Fetal Pregnancy Complications of in Minors Raped with or without Physical Restraint in Eastern Democratic Republic of Congo
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作者 Kiminyi Kalunga Eloge Ilunga-Mbaya +2 位作者 Raha Maroy Yoyu Tunangoya Jonathan Nyakio Ngeleza Olivier 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第1期1-12,共12页
Introduction: Pregnancy resulting from rape is a public health and sexual and reproductive health issue, especially among minors. Rape can be perpetrated with or without physical restraint. The objective of the presen... Introduction: Pregnancy resulting from rape is a public health and sexual and reproductive health issue, especially among minors. Rape can be perpetrated with or without physical restraint. The objective of the present study is to highlight the prevalence of physical coercion leading to pregnancy and the associated maternal-fetal complications. Methodology: This was a comparative descriptive and analytical cross-sectional study of complications associated with post-rape pregnancy by physical restraint among minors who were treated at the General Reference Hospital of Panzi over a two-year period from June 2020 to June 2022. A total of 140 minor survivors of violence with pregnancy were included in the study. Data were collected using a questionnaire, coded and analyzed in Excel and XLSTAT version 2014. Results: The prevalence of physical constraints was 65%. After mulltivariate analyses, denial of pregnancy (ORa: 9.64 95% CI: 1.1 - 81.2;p-value: 0.0370), attempted abortion (ORa: 56.1 95% CI: 1.5 - 2027.6;p-value: 0.0278) and agitation during delivery (ORa: 88.7 95% CI: 4.5 - 1715;p-value: 0.0030) were the complications associated with pregnancy in minors who experienced physical restraint rape. In addition, BMI was a factor in reducing the risk of physical restraint rape at the ORa of 0.5054 [0.3;0.8];p 0.006). Conclusion: Pregnancy among minors is a reality and occurs in a situation of physical coercion in the eastern Democratic Republic of Congo. These pregnancies are often associated with complications that require an intensive management system since they can jeopardize the maternal-fetal prognosis of minors. 展开更多
关键词 Post-rape Pregnancy MINOR Associated Complications Eastern DRC
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油菜高速机械离心式集排器设计与试验 被引量:1
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作者 廖庆喜 沈文惠 +3 位作者 王磊 霍佳琪 罗湛程 廖宜涛 《农业机械学报》 EI CAS CSCD 北大核心 2024年第7期154-167,共14页
针对传统油菜机械离心式集排器高速作业时供种及投种能力不足,导致排种量与作业速度不匹配、排种性能不稳定等问题,设计了一种被动式供种、“圆孔+渐变孔柱”组合式型孔投种的油菜高速机械离心式集排器。构建了供种、投种过程中的力学模... 针对传统油菜机械离心式集排器高速作业时供种及投种能力不足,导致排种量与作业速度不匹配、排种性能不稳定等问题,设计了一种被动式供种、“圆孔+渐变孔柱”组合式型孔投种的油菜高速机械离心式集排器。构建了供种、投种过程中的力学模型,分析确定了影响排种性能的关键结构参数;利用EDEM离散元仿真开展了供种调节高度对供种速率调节量影响的试验,结果表明当供种调节高度为3~8 mm时,供种速率在64.95~357.54 g/min范围内可调;采用两因素三水平正交试验分析了限种套筒下摆高度及倾角对初始种量、临界转速及环状种层最大高度的影响。通过台架试验确定了较优限种套筒结构参数,结合高速摄影对比了5种型孔结构下动锥体转速与排种量关系,确定最优型孔结构为“圆孔+渐变孔柱”组合式型孔。较优参数组合集排器排种性能验证试验结果表明:当转速为115~205 r/min时,排种速率为60.96~355.76 g/min,油菜各行排量一致性变异系数均低于5.2%,总排量稳定性变异系数均低于1.3%,破损率低于0.5%,满足作业速度6~12 km/h时的排种量要求。田间试验结果表明,当机组作业速度为7.89、11.98 km/h时,油菜各行植株均匀性变异系数低于11%,种植密度为43~58株/m^(2),满足油菜精量播种要求。 展开更多
关键词 油菜 高速机械离心式集排器 型孔结构 离散元仿真
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强制、同意与性别平等:强奸罪入罪模式及其改革 被引量:1
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作者 向燕 《政治与法律》 CSSCI 北大核心 2024年第6期113-127,共15页
我国刑法规定的强奸罪确立了以“强制手段”为核心要素的规范结构,可概括为强制模式。在强制手段或被害人反抗不明显的情形中,行为人违反被害人意愿实施性行为却难以受到刑法的制裁,从而使个人性自主权的保护存在重大漏洞。强制不是强... 我国刑法规定的强奸罪确立了以“强制手段”为核心要素的规范结构,可概括为强制模式。在强制手段或被害人反抗不明显的情形中,行为人违反被害人意愿实施性行为却难以受到刑法的制裁,从而使个人性自主权的保护存在重大漏洞。强制不是强奸罪不法的核心,违背他人意志才是强奸罪的本质。以同意替代强制是强奸罪法律规范发展的必然趋势。强奸罪立法的主要任务是为个体之间的性互动确立一个相对客观的、符合社会规范和性别平等价值的沟通规则。根据性互动的沟通结构及其特点,结合性互动行为的实践和不同模式的适用效果,我国宜采取修正的否定同意模式,即一般情形下适用否定同意模式,对虽然具有同意能力但其认知能力和防卫能力存在减损的脆弱人群应适用积极同意模式。 展开更多
关键词 强奸罪 强制 同意 性别平等 沟通
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油菜角果叶绿素含量传感检测技术在农业信息化中的应用研究 被引量:2
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作者 陈敏 廖桂平 苏招红 《智慧农业导刊》 2024年第8期21-24,29,共5页
该文研究油菜叶绿素含量传感检测技术在农业信息化中的应用,探讨其在作物生长监测、营养管理与施肥优化、病虫害预测与防控等方面的重要性。通过分析突出该技术在提高农业生产效率、实现资源精细管理方面的广泛应用。最后,该文也讨论该... 该文研究油菜叶绿素含量传感检测技术在农业信息化中的应用,探讨其在作物生长监测、营养管理与施肥优化、病虫害预测与防控等方面的重要性。通过分析突出该技术在提高农业生产效率、实现资源精细管理方面的广泛应用。最后,该文也讨论该技术面临的测量误差与精度问题、传感器的稳定性与耐久性等挑战,期望通过不断深化研究,该技术能够更好地服务于现代农业的可持续发展与智能化管理。 展开更多
关键词 油菜 叶绿素含量 传感检测 农业信息化 应用研究
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面向夹持采收的油菜薹夹段茎秆离散元参数标定与优化
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作者 谢伟 欧阳琛 +2 位作者 蒋蘋 孟德鑫 罗海峰 《农业工程学报》 EI CAS CSCD 北大核心 2024年第7期104-116,共13页
为提高离散元法对指导油菜薹有序采收装备设计与优化的准确性和可靠性,该研究以双行垄作移栽的“农大1号”双低甘蓝型油菜机械化适收期油菜薹夹段茎秆为对象,测定其本征参数、表面接触参数以及破碎力学参数,利用EDEM仿真软件Hertz-Mind... 为提高离散元法对指导油菜薹有序采收装备设计与优化的准确性和可靠性,该研究以双行垄作移栽的“农大1号”双低甘蓝型油菜机械化适收期油菜薹夹段茎秆为对象,测定其本征参数、表面接触参数以及破碎力学参数,利用EDEM仿真软件Hertz-Mindlin无滑移模型和Hertz-Mindlin with bonding粘结模型建立夹段茎秆堆积仿真标定模型和破碎仿真标定模型。采用逐步调整仿真参数使仿真试验值与物理试验值逼近的方法,利用夹段茎秆堆积仿真标定模型,以休止角仿真试验值与实际物理试验值的相对误差为目标,完成夹段茎秆表面接触参数的标定与优化;利用破碎仿真标定模型,以轴向压缩和弯曲仿真试验与实际物理试验的最大轴向压缩力和最大弯曲力的相对误差为目标,利用标定后的表面接触参数完成夹段茎秆粘结参数的标定与优化。最后,利用夹段茎秆的径向压缩与剪切、内芯与表皮拉伸的破碎仿真力学试验和有序采收EDEM-Recurdyn耦合仿真试验验证标定后的表面接触参数和粘结参数。结果表明,仿真与实测试验的破碎力学参数相对误差在5%以内,且仿真与实测的“时间-载荷”曲线变化趋势一致,低速、中速和高速档的有序采收仿真试验结果与实际物理试验结果相对误差在7.0%以内。研究结果表明,采用离散元仿真方法研究油菜薹采收过程具有可行性,标定结果可用于指导油菜薹机械化生产。 展开更多
关键词 离散元 模型 油菜薹 仿真 参数标定
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不同施氮水平对冬油菜根际微生物群落特征的影响
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作者 刘东海 张智 +5 位作者 梅亮贤 乔艳 刘东伟 肖卓熙 李菲 胡诚 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第10期1898-1908,共11页
【目的】探究冬油菜根际微生物群落特征对不同施肥的响应,确定油菜氮肥适宜用量,为土壤培肥和调控土壤生态功能提供理论依据【方法】田间试验在油菜种植区(武穴)开展,在秸秆还田条件下设置5个处理:不施氮肥(SN0)、N 120 kg/hm^(2)(SN120... 【目的】探究冬油菜根际微生物群落特征对不同施肥的响应,确定油菜氮肥适宜用量,为土壤培肥和调控土壤生态功能提供理论依据【方法】田间试验在油菜种植区(武穴)开展,在秸秆还田条件下设置5个处理:不施氮肥(SN0)、N 120 kg/hm^(2)(SN120)、N 180 kg/hm^(2)(SN180)、N 240 kg/hm^(2)(SN240)和N 300 kg/hm^(2)(SN300),采用16S rRNA和ITS高通量测序方法,分析根际土壤细菌和真菌群落结构及其功能变化,同时测定土壤理化性质和作物产量。【结果】1)与不施氮处理(SN0)相比,施氮处理降低了根际土壤有效磷含量(24.63%~35.10%)和速效钾含量(39.67%~59.77%),提高了全氮(6.18%~14.60%)和碱解氮含量(7.18%~34.99%)。SN180处理提升土壤全氮和碱解氮含量的幅度最小,SN300处理提升幅度最大。随着氮肥的增加,有机碳含量呈增长趋势,pH呈下降趋势,油菜产量先增加后减少,SN180产量最高。2)随着施氮量的递增,细菌的Chao1指数呈递增趋势;与SN0处理相比,SN180处理提高了真菌Shannon指数7.20%。施氮肥改变了细菌和真菌群落结构。与SN0处理相比,SN180处理提高了子囊菌门、担子菌门和拟杆菌门相对丰度,降低了被孢霉门和酸杆菌门相对丰度,减缓了鞘氨醇单胞菌和芽孢杆菌属的减少趋势,富集了红假单胞菌属(Rhodopseudomonas)和线黑粉酵母属(Filobasidium)。与SN0处理相比,施氮处理均降低了化学异养、固氮、芳香化合物降解和几丁质分解功能菌群的丰度,同时降低undefined saprotroph丰度。3)环境因子与群落关联网络分析和RDA分析显示,土壤有机碳(SOC)、碱解氮(AN)、全氮(TN)和有效磷(AP)含量是影响真菌群落的主要环境因子,SOC和AP含量是细菌群落的主要影响因子。无色穗孢属(Achroiostachys)与SOC含量呈负相关,与AN呈正相关。Emericellopsis与AN和TN含量呈显著负相关,与pH呈显著正相关。SOC与类诺卡氏属(Nocardioides)显著正相关,与厌氧粘细菌属(Anaeromyxobacter)显著负相关。【结论】从产量、群落多样性及富集有益微生物角度综合分析,冬油菜施用N 180 kg/hm^(2)是较合理的氮肥用量。 展开更多
关键词 氮肥 冬油菜 微生物群落结构 功能预测
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广西不同绿肥油菜品种的养分累积差异及富硒品种筛选
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作者 贾海江 路丹 +5 位作者 范晓苏 石保峰 张宏旺 丘益明 黄崇峻 沈方科 《贵州农业科学》 CAS 2024年第8期8-18,共11页
【目的】探明不同绿肥油菜品种的养分差异及对土壤硒富集效应,为丰富绿肥油菜品种及广西富硒土壤资源应用提供理论依据。【方法】以川油36(CY36)、丰油823(FY823)和沣油919(FY919)等19个绿肥油菜品种为研究对象,采用盆栽试验,研究不同... 【目的】探明不同绿肥油菜品种的养分差异及对土壤硒富集效应,为丰富绿肥油菜品种及广西富硒土壤资源应用提供理论依据。【方法】以川油36(CY36)、丰油823(FY823)和沣油919(FY919)等19个绿肥油菜品种为研究对象,采用盆栽试验,研究不同品种生物量,氮、磷、钾和钙养分累积差异及对土壤硒吸收、富集的响应。【结果】不同绿肥油菜品种之间的地上部生物量、地下部生物量和总生物量均存在一定差异。地上部干生物量为4.49~6.62 g/盆,地下部为0.14~0.84 g/盆;总干生物量为4.82~7.14 g/盆。总生物量前3位的中双9号、沣油958和南油12显著高于生物量最低的3个品种(花油8号、川油36和华湘油12号);地上部氮、磷、钾和钙养分含量分别为8.86~19.64 g/kg、 0.69~2.24 g/kg、 13.07~37.68 g/kg和11.82~34.23 g/kg。浙油51号和花油6号地上部和地下部的养分含量均较高。氮、磷、钾和钙含量综合评分排序前3位的油菜品种为浙油51、中双10号和花油6号。硒含量地上部为0.095~0.369 mg/kg,地下部为0.160~0.579 mg/kg;全株硒含量为0.111~0.382 mg/kg;沣油919、绵油88和圣光86的地上部、地下部和全株硒含量较高,均显著高于其他油菜品种;硒总累积量在0.552~2.286μg/盆,沣油919和绵油88显著高于其他油菜品种。【结论】综合各品种的养分累积量和硒素吸收特性,沣油919、绵油88和圣光86的富硒能力较强,可作为广西富硒土壤资源高效利用的绿肥油菜品种。 展开更多
关键词 绿肥油菜 生物量 养分累积 硒含量 转移系数 广西
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油菜抗根肿病品种在云南省西南发病区的田间评价
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作者 赵凯琴 张立帆 +4 位作者 张云云 刘珏 罗佳杰 杨兆春 罗延青 《农学学报》 2024年第2期16-22,共7页
通过明确‘华双5R’和‘华油杂62R’2个抗根肿病油菜品种的田间抗性、农艺性状和产量情况,为油菜根肿病重发区筛选出优良的抗病品种。本研究在云南省西南地区的腾冲市、梁河县和临翔县3个油菜根肿病病区进行田间试验,采用本课题组研发... 通过明确‘华双5R’和‘华油杂62R’2个抗根肿病油菜品种的田间抗性、农艺性状和产量情况,为油菜根肿病重发区筛选出优良的抗病品种。本研究在云南省西南地区的腾冲市、梁河县和临翔县3个油菜根肿病病区进行田间试验,采用本课题组研发品种和当地主推品种作为对照。田间试验结果显示,‘华双5R’和‘华油杂62R’在3个试验点均能正常成熟安全越冬,生育期176~199d,各生育期表现整齐一致;‘华双5R’和‘华油杂62R’在腾冲和梁河点对油菜根肿病表现为高度抗病,在临翔点表现为抗病;‘华双5R’和‘华油杂62R’在3个试验点的农艺性状良好;‘华双5R’的产量在3个试验点与7个对照品种相比,比梁河点的‘云油杂12号’减产2.71%,与腾冲点的‘云油杂12号’和‘杂1256’、梁河点的‘云油杂15’和‘花油8号’、临翔点的‘云油杂12号’和‘德油1号’相比增产幅度为7.49%~56.83%;‘华油杂62R’的产量在3个试验点与7个对照品种相比,比梁河点的‘云油杂12号’减产5.76%,比临翔点的‘德油1号’减产4.61%,与腾冲点的‘云油杂12号’和‘杂1256’、梁河点的‘云油杂15’和‘花油8号’、临翔点的‘云油杂12号’相比增产幅度为4.12%~51.90%。‘华双5R’和‘华油杂62R’在3个试验点均能正常成熟,生育期176~199d,对根肿病表现出较强抗性,同时农艺性状良好、产量较高,可在云南省西南地区油菜根肿病病区推广种植。 展开更多
关键词 油菜 根肿病 抗性鉴定 抗性品种 田间栽培
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