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Harnessing perennial and indeterminant growth habits for ratoon cotton(Gossypium spp.)cropping

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Ecosystem Health and Sustainability 2020年第1期6卷 354-366,353页

作者： Xin Zhang Xiangjun Kong ruiyang zhou Zhiyong Zhang Jinbao Zhang Linsong Wang Qinglian Wang Postdocotoral Research Base Henan Collaborative Innovation Centre of Modern Biological BreedingHenan Institute of Science and TechnologyXinxiangChina Biological Postdoctoral Research Station Henan Normal UniversityXinxiangChina College of Agronomy Guangxi UniversityNanningGuangxiChina

Ratoon is the stub or root of a perennial plant that is commonly retained after harvest to produce a following *** paper presents a review of ratoon cotton in relation to a broader framework that has been examining perennialization of agriculture for the benefit of ecology and *** is botanically indeterminate,but has been treated as an annual after domestication,yet the habit of perenniality is retained and the plants begin to resprout after the first *** some cropping systems,this tendency is exploited using the“ratooning”practice(*** one or more crops on the rootstock of the first).Ratooning has declined for various reasons such as an increase in the prevalence of pests and diseases and overwintering ***,ratooning has many benefits such as no annual tillage before sowing,a well-established root system,and high *** three methods of ratooning offer flexibility to balance the environmental and economic benefits in *** greatest environmental benefits arise from perennial ratoon cropping of semi-wild cotton,and the greatest economic benefit is obtained from biannually cropping modern annual ***,an optimum solution would be provided by perennial cropping annual *** realize both environmental and economic benefits,research is needed in the following main areas:preventing the buildup of pests and diseases,breeding the most suitable cotton cultivars for ratooning,and developing light and simplified cultivation(LSC)systems for ratoon cultivation.

关键词： Cotton perennial indeterminant ratoon stub tropics

An SEIHR model with age group and social contact for analysis of Fuzhou COVID-19 large wave

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Infectious Disease Modelling 2024年第3期9卷 728-743页

作者： Xiaomin Lan Guangmin Chen ruiyang zhou Kuicheng Zheng Shaojian Cai Fengying Wei Zhen Jin Xuerong Mao School of Mathematics and Statistics Fuzhou UniversityFuzhou350116FujianChina Fujian Provincial Center for Disease Control and Prevention Fuzhou350012FujianChina Center for Applied Mathematics of Fujian Province Fuzhou350116FujianChina Key Laboratory of Operations Research and Control of Universities in Fujian Fuzhou UniversityFuzhou350116FujianChina Complex Models Research Center Shanxi UniversityTaiyuan030006ShanxiChina Department of Mathematics and Statistics University of StrathclydeGlasgowG11XHUK

The main epidemiological features such as basic reproduction number,effective reproduction number and sensitivity analysis were extensively discussed for multi-age groups SEIHR model in this ***,by using of the next generation matrix method,basic reproduction number R0 of the total population was estimated as 1.57 using parameter values of four age groups of Fuzhou COVID-19 large *** age group k,the values of R_(0k)(age group k to age group k),the values of R_(o)^(k)(an infected of age group k to the total population)and the values of R_(o)^(k)>R_(0k)>R_(o)^(k)(an infected of the total population to age group k)were also estimated,in which the explorations of the impacts of age groups revealed that the relationship was ***,the fluctuating tendencies of effective reproduction number Rt were demonstrated by using two approaches(the surveillance data and the SEIHR model)for Fuzhou COVID-19 large wave,during which high-risk group(G4 group)mainly contributed the infection scale due to high susceptibility to infection and high risks to basic ***,the sensitivity analysis using two approaches(the sensitivity index and the PRCC values)revealed that susceptibility to infection of age groups played the vital roles,while the numerical simulation showed that infection scale varied with the changes of social contacts of age *** results of this study claimed that the high-risk group out of the total population was concerned by the local government with the highest susceptibility to infection against *** This study verified that the partition structure of age groups of the total population,the susceptibility to infection of age groups,the social contacts among age groups were the important contributors of infection *** less social contacts and adequate hospital beds for high-risk group were profitable to control the spread of *** avoid the emergence of medical runs against new variant in the future,the polic

关键词： COVID-19 model Age group Omicron BA.5.2 variant Contact matrixSocial contact

Dynamic evolution of an SVEIR model with variants and non-pharmaceutical interventions for controlling COVID-19

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Journal of Biosafety and Biosecurity 2024年第2期6卷 67-75页

作者： ruiyang zhou Shaojian Cai Guangmin Chen Senzhong Huang Zhen Jin Zhihang Peng Weichuan Lin Fengying Wei Kuicheng Zheng School of Mathematics and Statistics Fuzhou UniversityFuzhou 350116FujianChina Fujian Provincial Center for Disease Control and Prevention Fuzhou 350012FujianChina School of Statistics and Data Science ZhiYing Research Center for Health DataNankai UniversityTianjin 300071China Complex Systems Research Center Shanxi UniversityTaiyuan 030006ShanxiChina Department of Biostatistics School of Public HealthNanjing Medical UniversityNanjing 211166JiangsuChina School of Mathematics and Statistics Fujian Normal UniversityFuzhou 350007FujianChina Center for Applied Mathematics of Fujian Province Fuzhou UniversityFuzhou 350116FujianChina Key Laboratory of Operations Research and Control of Universities in Fujian Fuzhou UniversityFuzhou 350116FujianChina Fujian Provincial Key Laboratory of Zoonosis Research Fuzhou 350001FujianChina Teaching Base of the School of Public Health of Fujian Medical University Fuzhou 350001FujianChina

The epidemiological characteristics and distributions of two epidemics in Fujian Province of Southeast China were attributed to the complex interactions among variant,host,and non-pharmaceutical interventions(NPIs).All reported cases in the Putian epidemic(September 8–October 2,2021,Delta variant B.1.617.2)and Fuzhou epidemic(October 22–November 18,2022,Omicron variant BA.5.2)were classified by sex,age group,occupation,and location in this *** surveillance data from the Fujian Provincial Center for Disease Control and Prevention,we established a virus-oriented SVEIR(Susceptible–Vaccinated–Exposed–Infected–Recovered)model to investigate the dynamic evolution features of these two variants and the effects of *** optimal simulations were carried out with variants and scenario *** scenario investigations showed that NPIs significantly reduced the transmission risk and infection scales of COVID-19,and that the Omicron variant was more infectious than the Delta ***,the dynamic investigations revealed the increasing tendencies from Delta to Omicron,such as the basic reproduction number,infection rate,percentage of high-risk cases,and the growth *** tendencies were also identified,such as the average recovery period,the awareness delay,and the percentage of symptomatic *** study highlighted that NPIs played critical roles in successfully containing the two *** interventions are strongly recommended to public health policymakers.

关键词： COVID-19 SVEIR model Transmission dynamics Non-pharmaceutical interventions Delta variant Omicron variant

COVID-19 transmission driven by age-group mathematical model in Shijiazhuang City of China

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Infectious Disease Modelling 2023年第4期8卷 1050-1062页

作者： Fengying Wei ruiyang zhou Zhen Jin Senzhong Huang Zhihang Peng Jinjie Wang Ximing Xu Xinyan Zhang Jun Xu Yao Bai Xiaoli Wang Bulai Lu Zhaojun Wang Jianguo Xu School of Mathematics and Statistics Fuzhou UniversityFuzhou350116FujianChina Center for Applied Mathematics of Fujian Province Fuzhou UniversityFuzhou350116FujianChina Key Laboratory of Operations Research and Control of Universities in Fujian Fuzhou UniversityFuzhou350116FujianChina Complex Systems Research Center Shanxi UniversityTaiyuan030006ShanxiChina School of Statistics and Data Science ZhiYing Research Center for Health DataNankai University300071TianjinChina Department of Biostatistics School of Public HealthNanjing Medical UniversityNanjing211166JiangsuChina Nankai Institute of Economics Binhai Development InstituteNankai UniversityTianjin300071China Children's Hospital of Chongqing Medical University Chongqing400010China Jinzhou Center for Disease Control and Prevention Jinzhou121000LiaoningChina School of Statistics and Data Science Nankai UniversityTianjin300071China Xi'an Center for Disease Control and Prevention Xi'an710061ShaanxiChina Beijing Center for Disease Control and Prevention Beijing100013China Suzhou Center for Disease Control and Prevention Suzhou215004JiangsuChina State Key Laboratory of Communicable Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing102206China Institute of Public Health Nankai UniversityTianjin300071China

Background:A COVID-19 outbreak in the rural areas of Shijiazhuang City was attributed to the complex interactions among vaccination,host,and non-pharmaceutical interventions(NPIs).Herein,we investigated the epidemiological characteristics of all reported symptomatic cases by picking Shijiazhuang City,Hebei Province in Northern China as research *** addition,we established an age-group mathematical model to perform the optimal fitting and to investigate the dynamical profiles under three ***:All reported symptomatic cases of Shijiazhuang epidemic(January 2-February 3,2021)were investigated in our *** cases were classified by gender,age group and location,the distributions were analyzed by epidemiological ***,the reported data from Health Commission of Hebei Province was also analyzed by using an age-group mathematical model by two phases and three ***:Shijiazhuang epidemic caused by SARS-CoV-2 wild strain was recorded with the peak 84 cases out of 868 reported symptomatic cases on January 11,2021,which was implemented with strong NPIs by local government and referred as baseline situation in this *** research results showed that R0 under baseline situation ranged from 4.47 to 7.72,and Rt of Gaocheng Distinct took 3.72 with 95%confidence interval from 3.23 to 4.35 on January 9,the declining tendencies of Rt under baseline situation were kept till February 3,the value of Rt reached below 1 on January 19 and remained low value up to February 3 for Gaocheng District and Shijiazhuang City during Shijiazhuang *** indicated Shijiazhuang epidemic was under control on January ***,if the strong NPIs were kept,but remote isolation operated on January 11 was not implemented as of February 9,then the scale of Shijiazhuang epidemic reached 9,482 cases from age group who were 60 years old and over out of 31,017 symptomatic *** investigation also revealed that Shijiazhuang epidemic reache

关键词： COVID-19 Wild strain Non-pharmaceutical interventions Shijiazhuang epidemic Transmission dynamics

基于YOLOv3的芯片缺陷检测模型设计与优化

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半导体技术 2024年第7期49卷 660-665页

作者：林文迪周睿阳邸志雄西南交通大学信息科学与技术学院成都3611756

传统的芯片缺陷检测效率低,鉴于深度学习在机器视觉领域应用广泛且效果显著,基于YOLOv3神经网络模型设计了微波芯片缺陷检测模型并加以优化。将原来的损失函数改为完全交并比(CIoU)损失函数,以优化真实框与预测框之间重合度的计算方法;... 详细信息

传统的芯片缺陷检测效率低,鉴于深度学习在机器视觉领域应用广泛且效果显著,基于YOLOv3神经网络模型设计了微波芯片缺陷检测模型并加以优化。将原来的损失函数改为完全交并比(CIoU)损失函数,以优化真实框与预测框之间重合度的计算方法;增加了空间金字塔池化(SPP)结构,以实现不同尺寸特征融合;用高效的k-means++聚类算法计算出更加适用于微波芯片缺陷数据集的初始锚框;采用空间注意力机制(SAM)提高模型对芯片缺陷图像的关注能力。实验结果表明,与YOLOv3模型相比,优化后的模型在芯片缺陷检测方面效果更佳,mAP@0.5提高了2.06%,mAP@[0.5∶0.95]提高了17.52%。

关键词：深度学习 YOLOv3 芯片缺陷检测完全交并比(CIoU) 空间金字塔池化(SPP)

水稻^(60)Co γ辐照诱变雄性不育突变体的败育特征与遗传分析

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作物杂志 2012年第4期 75-78,F0003页

作者：肖人鹏周长海周瑞阳广西大学农学院广西南宁530005

用406.8 Gy60Coγ辐照诱变水稻品系08-208+7的干种子,从M3代中获得3株雄性不育突变株ms1、ms2和ms3。对其小孢子败育的细胞学观察表明,ms1为典败型,其败育时期为单核至双核期;ms2和ms3表现为无花粉型,败育时期为减数分裂二分体至四分体... 详细信息

用406.8 Gy60Coγ辐照诱变水稻品系08-208+7的干种子,从M3代中获得3株雄性不育突变株ms1、ms2和ms3。对其小孢子败育的细胞学观察表明,ms1为典败型,其败育时期为单核至双核期;ms2和ms3表现为无花粉型,败育时期为减数分裂二分体至四分体时期。遗传研究表明,各类型均为单基因隐性遗传;ms1分别与ms2、ms3相互不等位,ms2与ms3之间相互等位。

关键词：水稻雄性不育败育特征遗传分析

适合于基因组测序的红麻高纯度线粒体DNA提取

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东北农业大学学报 2011年第4期42卷 98-101页

作者：赵杨陈鹏周瑞阳广西大学农学院南宁530004

采用红麻黄化苗为试材,结合密度梯度离心和差速离心的方法提取线粒体DNA(mtDNA)以满足测序要求。结果表明,蔗糖密度梯度离心法比Percoll密度梯度离心法更适合于红麻线粒体的分离。分离后的线粒体经DNaseI消化核DNA,并采用Jannus绿检测... 详细信息

采用红麻黄化苗为试材,结合密度梯度离心和差速离心的方法提取线粒体DNA(mtDNA)以满足测序要求。结果表明,蔗糖密度梯度离心法比Percoll密度梯度离心法更适合于红麻线粒体的分离。分离后的线粒体经DNaseI消化核DNA,并采用Jannus绿检测线粒体的完整性,SDS和蛋白酶K裂解线粒体,并用酚/氯仿抽提除去蛋白,乙醇沉淀得到线粒体DNA,再经RNaseA消化去除RNA。提取的mtDNA经1.0%琼脂糖凝胶电泳、紫外分光光度计检测,并设计叶绿体和核特异性基因引物检测是否有污染存在。结果表明,此方法提取的mtDNA纯度高,没有污染,满足基因组测序要求。

关键词：红麻线粒体 mtDNA 测序

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2008年广西南宁棉花种质资源越冬调查

作物杂志 2008年第6期 74-76页

作者：张新周瑞阳娄喜艳广西大学农学院广西南宁530005

广西南宁2008年1月中旬至2月中旬出现极端低温阴雨灾害天气。从2月下旬开始,对试验田种植的193份棉花种质资源进行越冬调查。结果表明,越冬材料萌芽时间主要集中在3月上中旬;有29份材料越冬,占参试材料的15.03%,其中有6份材料安全越冬;... 详细信息

广西南宁2008年1月中旬至2月中旬出现极端低温阴雨灾害天气。从2月下旬开始,对试验田种植的193份棉花种质资源进行越冬调查。结果表明,越冬材料萌芽时间主要集中在3月上中旬;有29份材料越冬,占参试材料的15.03%,其中有6份材料安全越冬;海岛棉的越冬存活率高于陆地棉;7个陆地棉细胞核雄性不育系均未越冬,陆地棉哈克尼西棉细胞质雄性不育系比与其配套的保持系越冬存活率高;越冬存活率随宿生年限的增长而下降。

关键词：棉花种质资源越冬

红麻雄性不育系、保持系及杂交F_2代越冬期间抗寒性的比较研究

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热带作物学报 2011年第1期32卷 79-82页

作者：周琼李正文周瑞阳广西大学农学院广西南宁530005

以红麻细胞质雄性不育系、保持系及杂交F2代为材料,鉴定其越冬期间,在自然低温胁迫条件下的抗寒性及相关生理生化指标的变化。结果表明:(1)经平均5.76℃连续15 d的自然低温胁迫后,不育系L23A和P3A的抗寒性明显强于其对应的保持系;在L23A... 详细信息

以红麻细胞质雄性不育系、保持系及杂交F2代为材料,鉴定其越冬期间,在自然低温胁迫条件下的抗寒性及相关生理生化指标的变化。结果表明:(1)经平均5.76℃连续15 d的自然低温胁迫后,不育系L23A和P3A的抗寒性明显强于其对应的保持系;在L23A/福红992杂交F2代植株中,不育株的抗寒性也明显强于可育株;(2)不育系L23A和P3A茎皮中可溶性糖、可溶性蛋白质、脯氨酸含量及超氧化物歧化酶活性等生理指标均高于保持系,而L23A和P3A的相对电导率比相应的保持系都小;(3)在L23A/福红992杂交F2代植株中,不育株茎皮中可溶性糖、脯氨酸含量及超氧化物歧化酶活性等高于可育株,相对电导率低于可育株,其抗寒性相关生理生化指标表现出与不育系、保持系相同的变化规律。

关键词：红麻细胞质雄性不育自然低温胁迫抗寒性