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Host-induced silencing of MpPar6 confers Myzus persicae resistance in transgenic rape plants
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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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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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Selenium-enriched and ordinary green tea extracts prevent high blood pressure and alter gut microbiota composition of hypertensive rats caused by high-salt diet 被引量:4
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作者 Meirong Wu Xiaobin Wu +3 位作者 Jiangxiong Zhu Fanglan Li Xinlin Wei Yuanfeng Wang 《Food Science and Human Wellness》 SCIE 2022年第3期738-751,共14页
High-salt diet is well recognized as a risk factor for hypertension,and dietary intervention plays a critical role in the prevention of hypertension.The current study investigated the effects of selenium-enriched gree... High-salt diet is well recognized as a risk factor for hypertension,and dietary intervention plays a critical role in the prevention of hypertension.The current study investigated the effects of selenium-enriched green tea(Se-GT)and ordinary green tea(GT)on prevention of hypertension of rats induced by high-salt diet,as well as their potential regulatory and mechanism.Our results showed that GT and Se-GT supplementations significantly prevented the increase of blood pressure(BP),activated the phosphoinosmde-3-kinase/protein kinase B(PI3K/Akt)signaling pathway,and regulated the gene expression related to BP,as well as improved the tissue damage like heart,liver,and kidneys.Besides,the key parameters associated with oxidative stress,inflammation and endothelial dysfunction were also altered by GT and Se-GT treatments.Importantly,GT or Se-GT administration adjusted the diversity and composition of the intestinal flora.Moreover,GT and Se-GT supplementations increased the abundance of beneficial bacteria and reduced the abundance of harmful or conditional pathogenic bacteria.More specifically,GT intake specifically and significantly enriched the relative abundance of Paraprevotella and Bacteroides,whereas Se-GT was characterized by specific and significant enrichment for Allobaculum and Bifidobacterium.Our results proved that dietary supplement of GT and Se-GT remarkably improved the vascular functions and effectively prevented tissue damage by regulation of intestinal flora,and thus preventing hypertension induced by high-salt diet. 展开更多
关键词 High-salt diet HYPERTENSION Green tea selenium-enriched green tea PI3K/Akt pathway Microbial profile
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Research on Strategies for the Development of Selenium-enriched Tea in Ankang City of Shaanxi Province in the Context of Targeted Poverty Alleviation 被引量:1
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作者 Jianbin YANG Hui ZHANG Yuan CHANG 《Asian Agricultural Research》 2020年第5期7-10,共4页
As an important symbol of agricultural and sideline products in Ankang City,selenium-enriched tea affects the development of regional agricultural and sideline industries.In this paper,the development status and probl... As an important symbol of agricultural and sideline products in Ankang City,selenium-enriched tea affects the development of regional agricultural and sideline industries.In this paper,the development status and problems of the selenium-enriched tea products of Ankang were analyzed in terms of capital,technology,management and sales mode.This research is of positive significance to the development of selenium-enriched products and other agricultural and sideline products of health value,and plays a very important role in promoting the cultivation of village-level characteristic industries and the effective realization of targeted poverty alleviation. 展开更多
关键词 Targeted poverty alleviation selenium-enriched tea industry Characteristic industries Development strategy
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Study on Extraction Method of Selenium-enriched Rice 被引量:1
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作者 Panxia LIANG Xiu LAN +6 位作者 Yongxian LIU Liping PAN Mengling NONG Ying XING Qing LIAO Shiyang LU Jinping CHEN 《Agricultural Biotechnology》 CAS 2018年第3期165-169,共5页
[Objectives] The aims were to optimize the extraction process of selenoproteins from selenium-enriched rice in Guangxi and provide references for the intensive processing and comprehensive utilization of selenium prot... [Objectives] The aims were to optimize the extraction process of selenoproteins from selenium-enriched rice in Guangxi and provide references for the intensive processing and comprehensive utilization of selenium protein resources. [Methods]Selenium-enriched rice was used as materials to extract selenoproteins by phosphate buffer extraction method and to optimize the extraction process of selenoproteins by using the orthogonal experiment. Proteins and selenium content was measured by Coomassie Brilliant Blue G-250 reagent and AFS( atomic fluorescence spectrometry) respectively. [Results] The most significant factor affecting extraction of rice Selenoproteins was extraction NaO H concentration,followed by the ratio of solid-liquid,temperature and then extraction time. The optimum extraction conditions of selenoproteins from rice were extraction temperature of 50 ℃,NaO H concentration of 0. 14 mol/L,extraction time of 5 h,and solid-liquid ratio of 1∶ 30. [Conclusions]The alkali extraction process optimized by orthogonal test could effectively improve the extraction rate of selenoproteins,and the optimized process parameters could be popularized and applied in practical production. 展开更多
关键词 selenium-enriched rice SELENOPROTEINS Orthogonal experiment Extraction efficiency
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Analysis of Influencing Factors in Production of Selenium-enriched Eggs 被引量:1
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作者 Hui HU Xu YANG +1 位作者 Yangchao CHEN Jiangong XIANG 《Asian Agricultural Research》 2022年第6期15-17,20,共4页
Selenium is an essential trace element for human health.Eating selenium-enriched eggs is conducive to easily and effectively solving the problem of selenium deficiency.In the production process of selenium-enriched eg... Selenium is an essential trace element for human health.Eating selenium-enriched eggs is conducive to easily and effectively solving the problem of selenium deficiency.In the production process of selenium-enriched eggs,different selenium sources,additive doses,feeding time,and the addition of other vitamins,trace elements,and methionine in the diet will influence the deposition of selenium in eggs.Through this review,it is intended to provide a reference for the practical,safe and economical production of selenium-enriched eggs. 展开更多
关键词 Laying hens selenium-enriched eggs Influencing factors Egg selenium conversion rate
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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:6
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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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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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Recommendations for Sustainable Development of Selenium-enriched Functional Agriculture in Guangxi under the New Normal
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作者 Yongxian LIU 《Asian Agricultural Research》 2017年第11期23-27,共5页
Taking Scientific Outlook on Development as the guiding principle,this paper introduced the principles of innovation,coordination,green,openness and sharing. Based on gifted advantages of selenium-enriched soil and se... Taking Scientific Outlook on Development as the guiding principle,this paper introduced the principles of innovation,coordination,green,openness and sharing. Based on gifted advantages of selenium-enriched soil and selenium-enriched industry development in Guangxi,it discussed current practice,stressed green,ecological,characteristic demonstration,transformation and upgrading,and targeted poverty alleviation. Finally,it came up with perspective,practical,and operational strategies and recommendations for development of selenium-enriched industry,to provide reference for sustainable development of selenium-enriched functional industry in Guangxi. 展开更多
关键词 selenium-enrichment Functional agriculture Strategic project Development recommendations
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Effect of Soil Selenium on Nutritional Quality of Vegetables in the Selenium-enriched Areas of Qinghai Plateau
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作者 Yu ZHANG 《Asian Agricultural Research》 2018年第5期66-72,共7页
In order to improve the added value of the main vegetable products in Qinghai Province,we researched the effect of soil selenium content on vegetable quality in selenium-enriched area of Qinghai. Through the analysis ... In order to improve the added value of the main vegetable products in Qinghai Province,we researched the effect of soil selenium content on vegetable quality in selenium-enriched area of Qinghai. Through the analysis of Qinghai selenium-enriched soil selenium content and5 kinds of main vegetables corresponds to the total selenium,part of the mineral elements and soluble sugar and VC content,the effects of soil selenium levels on selenium absorption and nourishment quality of vegetables were researched. The results showed that he Qinghai selenium-enriched soil selenium content in the range of 100. 00-563. 00 μg/kg,among them,the soil samples with sufficient selenium and rich selenium accounted for 76. 53% and 18. 88%,respectively. Soil selenium content of garlic sampling area was relatively high,and soil selenium content of sugar beet sampling area was relatively low. Vegetable selenium content was in the range of 11. 00-340. 94 μg/kg,the average content of total selenium content of garlic was up to 170. 40 μg/kg,and the average content of the total selenium content of radish is 73. 00 μg/kg.90. 63% of the vegetables in the region reached the level of sufficient selenium,and 70. 31% reached the level of selenium enrichment. The average content of Ca and Mg was higher than the national average. There was no significant correlation between selenium content of soil and vegetable and nutritional quality. 展开更多
关键词 selenium-enriched areas of Qinghai VEGETABLES SELENIUM Nutritional quality
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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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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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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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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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基于YOLO v5的直播油菜激光间苗系统设计与试验
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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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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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中国油菜种业发展现状与对策研究
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作者 惠成章 赵丽丽 刘爱群 《园艺与种苗》 CAS 2024年第2期92-94,共3页
油菜种业作为食用油产业链上游的关键链条,其稳定健康发展对于保障我国植物油供给安全至关重要。该文从品种选育与保护、种子生产与推广、种子市场规模等方面对我国油菜种业发展现状进行全面阐述,深刻分析我国油菜种业发展存在的优异种... 油菜种业作为食用油产业链上游的关键链条,其稳定健康发展对于保障我国植物油供给安全至关重要。该文从品种选育与保护、种子生产与推广、种子市场规模等方面对我国油菜种业发展现状进行全面阐述,深刻分析我国油菜种业发展存在的优异种质资源创新利用不足、突破性新品种缺乏、现有育种技术落后等问题,并从加大优异种质资源挖掘与创新利用、加快突破性新品种选育、加速现代油菜育种技术跨越式发展等方面提出推动我国油菜种业发展的政策建议。 展开更多
关键词 油菜种业 产业发展 政策建议
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强制、同意与性别平等:强奸罪入罪模式及其改革
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作者 向燕 《政治与法律》 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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农户油菜种植意愿影响因素实证分析——基于江西省325个油菜种植户的调查数据
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作者 张春美 曹冠乔 付江凡 《中国农机化学报》 北大核心 2024年第2期296-302,共7页
稳定发展油菜产业事关我国食用油安全战略,为扩大全国油菜种植面积,需要对农户油菜种植行为展开研究。基于江西省325份油菜种植户的调查数据,通过建立二元选择Logit模型,从农户生产特征、经济因素和政策因素等维度实证分析影响农户油菜... 稳定发展油菜产业事关我国食用油安全战略,为扩大全国油菜种植面积,需要对农户油菜种植行为展开研究。基于江西省325份油菜种植户的调查数据,通过建立二元选择Logit模型,从农户生产特征、经济因素和政策因素等维度实证分析影响农户油菜种植意愿的因素。研究表明:油菜种植面积、机械化水平、菜油售价、肥田效果、旅游开发增收效果、直接补贴力度、农机补贴情况和农业保险参保情况对农户油菜种植意愿具有正向影响,种植成本和水稻补贴力度则具有负向影响。其中菜油售价、旅游开发增收效果、农机补贴情况和农业保险参保情况在1%水平上显著,机械化水平和直接补贴力度在5%水平上显著。因此,建议相关部门可从加大补贴力度、完善农业技术支持体系、推广机械化种植、提高农业保险覆盖率、开发油菜观光旅游项目等方面制定政策措施。 展开更多
关键词 江西省 油菜 种植意愿 影响因素 LOGIT模型
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