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甘蓝型油菜EMS突变体库特异脂肪酸构成材料苗期耐寒性评价及其基因挖掘
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作者 何铭渊 邵亚楠 +6 位作者 刘华 崔晓辉 马芸芸 马少杰 刘子金 陈明训 郭媛 《西北农业学报》 北大核心 2026年第2期260-274,共15页
油菜是中国食用油及饲用蛋白质的重要来源,提高油菜种子含油量、优化脂肪酸组分以及增强抗寒性是油菜育种的重要目标。本研究利用甲基磺酸乙脂(Ethyl methane sulfonate,EMS)诱变甘蓝型油菜‘中双11’构建EMS突变体库,连续自交2次结合... 油菜是中国食用油及饲用蛋白质的重要来源,提高油菜种子含油量、优化脂肪酸组分以及增强抗寒性是油菜育种的重要目标。本研究利用甲基磺酸乙脂(Ethyl methane sulfonate,EMS)诱变甘蓝型油菜‘中双11’构建EMS突变体库,连续自交2次结合品质筛选获得特异脂肪酸构成材料259份,随后对在2022-2023年越冬期持续长时间低温天气下存活且收获种子充足的19份M_(4)材料进行耐寒性评价。结果表明,2份耐寒材料相较2份敏感材料酶促清除能力增强,活性氧和丙二醛(MDA)含量降低。进一步利用耐寒材料3Y1210-4#1和敏感材料3Y1353-2#4进行转录组测序分析,鉴定出2609个仅响应低温的差异表达基因。差异表达基因GO富集分析发现,这些基因广泛参与冷响应、脂肪酸合成、激素调节、氧化应激、渗透胁迫等过程。 展开更多
关键词 甘蓝型油菜 emS突变体库 特异脂肪酸构成 耐寒 转录组
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Leaders’ expectations of innovation and employees’ innovative behavior: The roles of employees’ expected positive performance outcomes and innovative self-efficacy
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作者 Qian Ma Hao Zhou 《Journal of Psychology in Africa》 2025年第1期7-19,共13页
Employees’innovative performance determines an organization’s innovation,which critically impacts its structural optimization and sustainability.Applying expectancy theory,we examined how and when the Pygmalion effe... Employees’innovative performance determines an organization’s innovation,which critically impacts its structural optimization and sustainability.Applying expectancy theory,we examined how and when the Pygmalion effect occurs in the relationship between leaders’expectations of innovation and employee innovative behavior.Our sample comprised 201 frontline employees(female=31.84%;mean age=41.48 years,SD=7.97 years)in a Chinese coal enterprise,who completed surveys on innovation expectations of leaders,expected positive performance outcomes,innovative self-efficacy and innovative behavior.The results revealed that employees’expected positive performance outcomes mediated the positive relationship between leaders’innovation expectations and their innovative behavior.Employees’innovative self-efficacy positively moderated the relationship between their expected positive performance outcomes and innovative behavior,with this relationship being stronger for employees with high innovative self-efficacy.Moreover,we validated the moderated mediation model.Findings suggest that leaders can stimulate employee innovative behavior through expressing expectations and they also need to consider the boundary conditions. 展开更多
关键词 expectations of innovation expected positive performance outcomes innovative behavior innovative self-efficacy organizational innovation
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Health expectations in patients with diabetes mellitus and the factors affecting it:an integrative systematic review
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作者 Shahrzad Ghiyasvandian Akram Sadat Sadat Hoseini +1 位作者 Mahnaz Atapour Zahra Behboodi Moghdam 《Frontiers of Nursing》 2025年第2期163-175,共13页
Objective:The aim of this study was to investigate the health expectations(HEs)in patients with diabetes and the factors affecting it using an integrative systematic review.Methods:A comprehensive literature search wa... Objective:The aim of this study was to investigate the health expectations(HEs)in patients with diabetes and the factors affecting it using an integrative systematic review.Methods:A comprehensive literature search was conducted in databases including PubMed,Scopus,Science Direct,Google Scholar,ProQuest,CINAHL,SID,Iran Doc,and Magiran without time limitation using related keywords.The systematic literature search was performed using a guide provided by York University.Results:From a total of 1883 articles,17 of them finally met the eligibility criteria.According to the findings of this study,HE of diabetic patients was included in four categories:“dynamism,”“consequentialism,”“comprehensive care,”and“access to facilities.”Also,these expectations can be influenced by various factors,including“developments in societies,”“changing the conditions of health care systems,”and“individual factors.”Conclusions:Health professionals should pay attention to the expectations of diabetic patients who are involved in complex disease conditions and consider meeting them as a key factor in providing patient-centered care,improving health outcomes,and patient satisfaction. 展开更多
关键词 DIABETES expectation HEALTH patient-centered care systematic review
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Parental cognitive ability effects on children’s logical reasoning ability:The mediating role of academic expectation and the family environment
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作者 Qing Wang Haiyan Xu Xuhuan Wang 《Journal of Psychology in Africa》 2025年第4期497-503,共7页
This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China ... This study investigated the relationship between parental cognitive ability and child logical reasoning ability,and the role of academic expectation and family environment in that relationship.Based on the 2020 China Family Panel Studies(CFPS)data,1491 children(girls ratio=53.78%;average grade=6.023 years,school grade standard deviation=1.825 years).Results following multiple regression model(OLS)show that the higher the parental cognitive ability,the higher the children’s logical reasoning ability.Secondly,parental academic expectation serves as a mediator between their cognitive ability and children’s logical reasoning ability for higher logical reasoning by children.Third,a possible family environment acts as a mediator in the relationship between parents’cognitive ability and children’s logical reasoning ability to be higher.We conclude from thesefindings that parents with high cognitive abilities can enhance their children’s logical reasoning skills not only by setting higher academic expectations,but also by cultivating a supportive family environment.Thesefindings imply a need for intervention to improve family quality of life to enhance children’s thinking abilities to optimize their academic learning. 展开更多
关键词 parental cognitive ability children’s logical reasoning ability academic expectation family environment intermediary role
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Directional Three‑Dimensional Macroporous Carbon Foams Decorated with WC_(1−x)Nanoparticles Derived from Salting‑Out Protein Assemblies for Highly Effective Electromagnetic Absorption
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作者 Yongzheng Chen Lixue Gai +5 位作者 Bo Hu Yan Wang Yanyi Chen Xijiang Han Ping Xu Yunchen Du 《Nano-Micro Letters》 2026年第3期1-21,共21页
Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usu... Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usually involves complex procedures and extremely depends on unidirectional freezing technique.Herein,we propose a groundbreaking approach that leverages the assemblies of salting-out protein induced by ammonium metatungstate(AM)as the precursor,and then acquire directional three-dimensional carbon-based foams through simple pyrolysis.The electrostatic interaction between AM and protein ensures well dispersion of WC_(1−x)nanoparticles on carbon frameworks.The content of WC_(1−x)nanoparticles can be rationally regulated by AM dosage,and it also affects the electromagnetic(EM)properties of final carbon-based foams.The optimized foam exhibits exceptional EM absorption performance,achieving a remarkable minimum reflection loss of−72.0 dB and an effective absorption bandwidth of 6.3 GHz when EM wave propagates parallel to the directional pores.Such performance benefits from the synergistic effects of macroporous architecture and compositional design.Although there is a directional dependence of EM absorption,radar stealth simulation demonstrates that these foams can still promise considerable reduction in radar cross section with the change of incident angle.Moreover,COMSOL simulation further identifies their good performance in preventing EM interference among different electronic components. 展开更多
关键词 3D macroporous carbon-based foams Directional pore channels Salting-out protein assemblies em wave absorption Directional dependence
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大麦种子EMS诱变过程的影响因素分析
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作者 柳小宁 牛小霞 +4 位作者 包奇军 赵锋 滕柄钦 潘永东 张华瑜 《分子植物育种》 北大核心 2025年第19期6495-6502,共8页
为了提高大麦种子EMS诱变过程中的突变概率,创制有效突变体库,以‘甘啤8号’大麦种子为例,通过设置种子诱变前期不同处理,不同的诱变时间及浓度,诱变完成后不同播种时间3个方面分析EMS诱变过程中的影响因素。结果显示,诱变前期种子的处... 为了提高大麦种子EMS诱变过程中的突变概率,创制有效突变体库,以‘甘啤8号’大麦种子为例,通过设置种子诱变前期不同处理,不同的诱变时间及浓度,诱变完成后不同播种时间3个方面分析EMS诱变过程中的影响因素。结果显示,诱变前期种子的处理方式对诱变效果影响显著,直接诱变的发芽率比浸泡诱变的发芽率高10.66%~37.98%,浸泡后种子对EMS的响应大于干种子直接诱变,2种方式诱变16 h,浸泡后诱变的半致死浓度为0.4%,干种子直接诱变的半致死浓度为0.8%;不同的诱变时间下发芽势和发芽率对中、低浓度(0%~0.6%)EMS的响应:8 h<16 h<12 h,对较高浓度(>0.6%)的响应:8 h<12 h<16 h。诱变不同时间后的半致死浓度分别为8 h为0.8%,12 h为0.3%或者0.4%,16 h为0.4%,EMS对根和芽的抑制随着诱变时间的延长而增大;诱变完成到播种时间段的控制对出苗率有决定性的作用,相同诱变浓度和诱变时间,诱变完成12 h后播种出苗率能达到60%,24 h后播种出苗率为49%,12 d后播种出苗率只有0.8%。因此,在EMS诱变大麦种子产生突变体的过程中,要在浸水萌动后,浓度在0.3%~0.4%,16 h的诱变条件,同时播种时间在诱变完成12 h左右完成,有利于提高EMS在种质资源的创制中突变效率。 展开更多
关键词 大麦种子 emS诱变 突变体
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紫苏EMS诱变后代的农艺性状分析
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作者 刘淑霞 王晓飞 +5 位作者 肖宇 吴青松 关向军 刘星雨 郑歆然 张宏伟 《黑龙江科学》 2025年第12期1-6,11,共7页
为研究EMS诱变紫苏后代的变化趋势,获得紫苏的有益突变材料尤其是早熟材料。以5个紫苏新品系“HZ24”“HZ54”“龙紫苏1号”“HZ15”和“区16”为供试材料,配制0(CK)、0.5%、1.0%、1.5%和2.0%不同浓度的EMS溶液进行紫苏种子诱变处理,分... 为研究EMS诱变紫苏后代的变化趋势,获得紫苏的有益突变材料尤其是早熟材料。以5个紫苏新品系“HZ24”“HZ54”“龙紫苏1号”“HZ15”和“区16”为供试材料,配制0(CK)、0.5%、1.0%、1.5%和2.0%不同浓度的EMS溶液进行紫苏种子诱变处理,分析紫苏M 1和M 2的农艺性状。结果表明,EMS对5个紫苏新品系的诱变效果显著,且随EMS浓度的增加紫苏材料诱变的畸变率增加,5个紫苏新品系均产生了多种类型的突变植株,这将为黑龙江省寒地紫苏种质资源的创新及新品种选育提供坚实的材料基础。 展开更多
关键词 紫苏 emS化学诱变 突变体
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基于“VHSD-EM”模型的专精特新“小巨人”企业数字化成熟度评价 被引量:4
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作者 唐孝文 曹雪瑞 陈鑫 《科技进步与对策》 北大核心 2025年第3期141-151,共11页
专精特新“小巨人”企业数字化升级能够助力制造业强链补链,使其走上高质量发展快车道,对制造业强国建设具有重要意义。基于2016—2022年相关数据,运用“VHSD-EM”组合评价模型对“小巨人”企业数字化成熟度进行评价分析。结果表明:专... 专精特新“小巨人”企业数字化升级能够助力制造业强链补链,使其走上高质量发展快车道,对制造业强国建设具有重要意义。基于2016—2022年相关数据,运用“VHSD-EM”组合评价模型对“小巨人”企业数字化成熟度进行评价分析。结果表明:专精特新“小巨人”企业数字化成熟度可划分为4个等级,各等级样本企业在行业分布上呈现集聚趋势;先进制造业与传统制造业样本企业数字化成熟度呈现两极分化,基于空间维度的排序如下:中心城市>东南沿海地区>南部地区>西部地区>北部地区,且随时间推移波动较大;政府补贴、财政科技支出、市场竞争强度和企业规模总体上对“小巨人”企业数字化成熟度具有显著影响,但不同数字化成熟度等级样本企业影响因素存在差异。结论可为“小巨人”企业数字化实践提供参考。 展开更多
关键词 “小巨人”企业 数字化成熟度 “VHSD-em”模型 投入—产出理论 影响因素
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EMS型高速磁浮轨道不平顺参数影响研究 被引量:5
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作者 徐傲康 李苗 +3 位作者 王爱彬 尚贤洪 马卫华 罗世辉 《铁道标准设计》 北大核心 2025年第2期36-44,共9页
随着高速磁浮不断突破发展,针对轨道不平顺各控制参数对EMS型高速磁浮车辆运行下的动力学响应问题,基于多体动力学和有限元方法建立包含磁浮车辆系统、轨道梁系统以及控制系统组成的磁浮车辆-轨道-简支梁耦合系统模型,其中车辆系统与轨... 随着高速磁浮不断突破发展,针对轨道不平顺各控制参数对EMS型高速磁浮车辆运行下的动力学响应问题,基于多体动力学和有限元方法建立包含磁浮车辆系统、轨道梁系统以及控制系统组成的磁浮车辆-轨道-简支梁耦合系统模型,其中车辆系统与轨道梁系统使用磁轨关系进行耦合,并在多体动力学仿真软件中进行直线轨道梁耦合振动分析,探讨在时速600 km运行条件下轨道不平顺的幅值、方向、波长对EMS型高速磁浮耦合系统振动响应的影响,揭示系统中各项指标受不平顺影响的变化规律,探究高速磁浮车-轨-梁耦合系统轨道不平顺参数影响并提出参数建议。结果表明:对不平顺幅值研究时,磁浮车辆以600 km/h的速度在波长20 m的不平顺激励线路上运行时,耦合系统中某些动力指标超限,在含有波长20 m的不平顺线路幅值控制在4 mm以内为宜;在对垂向及横向不平顺研究时,发现车辆系统在垂向和横向的响应是解耦的,车辆垂向载荷是耦合系统中的主要激励因素,悬浮控制技术应作为高速磁浮系统重点关注的控制技术;对不平顺波长研究时,即使不平顺幅值在1 mm时,波长10 m以下短波不平顺相较于其他波长不平顺更易引起耦合系统的剧烈振动。 展开更多
关键词 emS型高速磁浮 轨道梁 轨道不平顺 耦合系统 车辆动力学
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Expectation-maximization(EM)Algorithm Based on IMM Filtering with Adaptive Noise Covariance 被引量:5
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作者 LEI Ming HAN Chong-Zhao 《自动化学报》 EI CSCD 北大核心 2006年第1期28-37,共10页
关键词 最大期望值 IMM滤波器 em算法 参数估计 噪音识别
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MATHEMATICAL EXPECTATION ABOUT DISCRETE RANDOM VARIABLE WITH INTERVAL PROBABILITY OR FUZZY PROBABILITY 被引量:2
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作者 肖盛燮 吕恩琳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第10期1382-1390,共9页
The character and an algorithm about DRVIP( discrete random variable with interval probability) and the secured kind DRVFP (discrete random variable with crisp event-fuzzy probability) are researched. Using the fu... The character and an algorithm about DRVIP( discrete random variable with interval probability) and the secured kind DRVFP (discrete random variable with crisp event-fuzzy probability) are researched. Using the fuzzy resolution theorem, the solving mathematical expectation of a DRVFP can be translated into solving mathematical expectation of a series of RVIP. It is obvious that solving mathematical expectation of a DRVIP is a typical linear programming problem. A very functional calculating formula for solving mathematical expectation of DRVIP was obtained by using the Dantzig's simplex method. The example indicates that the result obtained by using the functional calculating formula fits together completely with the result obtained by using the linear programming method, but the process using the formula deduced is simpler. 展开更多
关键词 interval number fuzzy set PROBABILITY random variable mathematical expectation
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AE-EM:一种期望最大化Web入侵检测算法 被引量:1
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作者 尹兆良 黄于欣 余正涛 《计算机工程与应用》 北大核心 2025年第3期315-325,共11页
现有的入侵检测算法集中在模式匹配、阈值分割法和多层感知机等机器学习和以神经网络深度学习方法上,在处理基于签名和异常的入侵时效果显著,但耗时费力。在面对Web入侵场景时,现有方法将检测模式重心放在网络流量分析(NTA)上,对URL携... 现有的入侵检测算法集中在模式匹配、阈值分割法和多层感知机等机器学习和以神经网络深度学习方法上,在处理基于签名和异常的入侵时效果显著,但耗时费力。在面对Web入侵场景时,现有方法将检测模式重心放在网络流量分析(NTA)上,对URL携带的负载信息和流量之间的关联语义信息提取不足,异常检测效果有待提升。提出一种无监督算法,名为注意力扩展期望最大化算法(attention expand expectation-maximization algorithm,AE-EM),该算法提取应用层URL中的攻击负载语义,采用Attention机制混合编码网络层流量结构化数据,训练融合多维特征和关联应用层语义的向量作为算法的输入,使用轻量化期望最大化算法估计高斯混合模型的参数,用于网络安全入侵检测的Web入侵检测场景。通过在基线数据集上使用常用的学习算法和消融实验比较,提出的AE-EM算法在Web入侵检测领域准确率和性能上优于传统算法。 展开更多
关键词 入侵检测 Web攻击检测 注意力机制 em算法 AE-em算法
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EM微生物菌剂对高海拔地区燕麦产量品质及土壤质量的影响 被引量:2
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作者 蔡宗程 吕亮雨 +5 位作者 高佩 李发毅 王玥 赵筱妍 苗金花 施建军 《中国土壤与肥料》 北大核心 2025年第9期138-149,共12页
旨在探讨EM微生物菌剂与牛、羊粪配施对高海拔地区燕麦产量、品质及土壤质量的影响。以‘青海甜燕麦’为材料,比较了不同剂量的EM菌剂(EM1、EM2、EM3、EM4、EM5)与牛、羊粪配施效果,并以不施肥作为对照(CK)。在生长季节(5—10月)观察了... 旨在探讨EM微生物菌剂与牛、羊粪配施对高海拔地区燕麦产量、品质及土壤质量的影响。以‘青海甜燕麦’为材料,比较了不同剂量的EM菌剂(EM1、EM2、EM3、EM4、EM5)与牛、羊粪配施效果,并以不施肥作为对照(CK)。在生长季节(5—10月)观察了各处理对燕麦生长发育、产量、品质、土壤养分及酶活性的影响。结果表明,施用EM菌剂显著促进了燕麦生长,尤其在株高、根总长、旗叶叶面积和鲜质量上,其中EM4处理的株高最高,较CK增加20.11%。光合作用方面,增施EM菌剂提高了燕麦SPAD值、光合速率、蒸腾速率、气孔导度和胞内CO_(2)浓度,其中EM3和EM4处理的净光合速率均超过13μmol/(m^(2)·s),较CK分别增加34.38%和33.57%。营养品质分析显示,EM3处理的粗蛋白和可溶性糖含量分别为7.13%和10.65%,较CK显著提高38.71%和32.46%,且总可消化养分含量均在60%以上,显著优于CK。在饲草产量方面,EM3处理的鲜草和干草产量最高,分别为28492.00和10928.80 kg/hm^(2),较CK分别增加28.57%和54.36%。土壤质量方面,施用EM菌剂后,土壤有机碳和全氮含量显著增加,EM3处理的全氮含量最高,较CK提高18.23%,同时土壤电导率和pH下降。土壤β-葡萄糖甘梅和N-乙酰-β-D-氨基葡萄糖苷酶活性在EM3处理达到峰值,分别较CK处理显著提高60.31%和70.68%。隶属函数综合评价分析显示,各处理对燕麦生长和土壤质量的改善效果依次为EM3>EM4>EM5>EM2>EM1>CK,表明EM3处理效果最佳。因此,在高海拔地区每公顷施用15.00 kg EM菌剂+18000 kg的牛羊粪组合效果最佳,显著促进了燕麦的生长发育,提高了其营养品质,并有效改善了土壤养分及酶活性。建议在高海拔地区推广该施肥方案,以提升燕麦的产量和土壤健康,促进高海拔地区燕麦饲草的绿色可持续生产。 展开更多
关键词 em微生物菌剂 燕麦 产量和品质 高海拔地区 土壤质量
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STRONG LIMIT THEOREMS FOR EXTENDED INDEPENDENT RANDOM VARIABLES AND EXTENDED NEGATIVELY DEPENDENT RANDOM VARIABLES UNDER SUB-LINEAR EXPECTATIONS 被引量:11
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作者 Li-Xin ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期467-490,共24页
Limit theorems for non-additive probabilities or non-linear expectations are challenging issues which have attracted a lot of interest recently.The purpose of this paper is to study the strong law of large numbers and... Limit theorems for non-additive probabilities or non-linear expectations are challenging issues which have attracted a lot of interest recently.The purpose of this paper is to study the strong law of large numbers and the law of the iterated logarithm for a sequence of random variables in a sub-linear expectation space under a concept of extended independence which is much weaker and easier to verify than the independence proposed by Peng[20].We introduce a concept of extended negative dependence which is an extension of the kind of weak independence and the extended negative independence relative to classical probability that has appeared in the recent literature.Powerful tools such as moment inequality and Kolmogorov’s exponential inequality are established for these kinds of extended negatively independent random variables,and these tools improve a lot upon those of Chen,Chen and Ng[1].The strong law of large numbers and the law of iterated logarithm are also obtained by applying these inequalities. 展开更多
关键词 Sub-linear expectation capacity extended negative dependence Kolmogorov’s exponential inequality laws of the iterated logarithm law of large numbers
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淮豆13 EMS诱变突变体库创制及大粒突变体鉴定 被引量:1
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作者 余希文 王亚琪 +4 位作者 李曙光 傅蒙蒙 赵志鑫 刘畅 徐海风 《江苏农业科学》 北大核心 2025年第2期128-135,共8页
淮豆13是一个高产广适多抗夏大豆品种,但百粒重偏低,为改良其百粒重性状,利用EMS(甲基磺酸乙酯)处理4 kg淮豆13种子,并进行连续4个世代的表型考察及筛选,同时对其中1个质量性状变异突变体进行了遗传解析。结果表明,经过M_(2)和M_(3)2个... 淮豆13是一个高产广适多抗夏大豆品种,但百粒重偏低,为改良其百粒重性状,利用EMS(甲基磺酸乙酯)处理4 kg淮豆13种子,并进行连续4个世代的表型考察及筛选,同时对其中1个质量性状变异突变体进行了遗传解析。结果表明,经过M_(2)和M_(3)2个世代筛选,获得了332个稳定遗传的突变体株系,涵盖茎秆、花、种子等多种类型的突变;筛选得到多个粒重增加或减少的材料,其中包括3个百粒重达28 g左右的突变体,M_(4)世代表型验证表明这3个粒重增大突变体单株产量无显著降低;此外,还鉴定得到了1个灰毛突变体,其农艺性状与野生型无差异,测序比对分析结果显示T基因第5942位碱基替换导致了终止密码子的出现,从而产生了灰毛表型。本研究成功地构造了变异丰富的淮豆13 EMS诱变突变体库,且成功筛选得到了3个单株产量不显著降低但百粒重显著增加的突变体株系,以及发现了1个点突变导致的灰毛突变体;为后续淮豆13品种改良提供了有价值的育种种质资源,也为后续淮豆13农艺性状遗传机理解析提供了丰富的遗传研究材料。 展开更多
关键词 淮豆13 emS诱变 大豆 大粒 突变体
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The Effects of Job Insecurity, Emotional Exhaustion, and Met Expectations on Hotel Employees’ Pro-Environmental Behaviors: Test of a Serial Mediation Model 被引量:1
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作者 Osman M.Karatepe Raheleh Hassannia +2 位作者 Tuna Karatepe Constanţa Enea Hamed Rezapouraghdam 《International Journal of Mental Health Promotion》 2023年第2期287-307,共21页
There are a plethora of empirical pieces about employees’pro-environmental behaviors.However,the extant literature has either ignored or not fully examined various factors(e.g.,negative or positive non-green workplac... There are a plethora of empirical pieces about employees’pro-environmental behaviors.However,the extant literature has either ignored or not fully examined various factors(e.g.,negative or positive non-green workplace factors)that might affect employees’pro-environmental behaviors.Realizing these voids,the present paper proposes and tests a serial mediation model that examines the interrelationships of job insecurity,emotional exhaustion,met expectations,and proactive pro-environmental behavior.We used data gathered from hotel customer-contact employees with a time lag of one week and their direct supervisors in China.After presenting support for the psychometric properties of the measures via confirmatory analysis in LISREL 8.30,the abovementioned linkages were gauged using the PROCESS plug-in for statistical package for social sciences.The findings delineated support for the hypothesized associations.Specifically,emotional exhaustion and met expectations partly mediated the effect of job insecurity on proactive pro-environmental behavior.More importantly,emotional exhaustion and met expectations serially mediated the influence of job insecurity on proactive pro-environmental behavior.These findings have important theoretical implications as well as significant implications for diminishing job insecurity,managing emotional exhaustion,increasing met expectations,and enhancing ecofriendly behaviors. 展开更多
关键词 emotional exhaustion hotel customer-contact employees job insecurity met expectations pro-environmental behavior
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基于HRM的茄子EMS突变体TILLING筛选技术体系的建立及应用
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作者 刘松瑜 周晓慧 +2 位作者 杨艳 刘军 庄勇 《分子植物育种》 北大核心 2025年第19期6411-6418,共8页
EMS诱变育种是作物种质创新的重要手段,利用反向遗传学手段TILLING(targeting induced local lesions in genomes)筛选EMS突变体,是研究基因功能与获得优良种质的有效手段之一。本研究采用基于HRM,即高分辨率熔解曲线分析技术的TILLING... EMS诱变育种是作物种质创新的重要手段,利用反向遗传学手段TILLING(targeting induced local lesions in genomes)筛选EMS突变体,是研究基因功能与获得优良种质的有效手段之一。本研究采用基于HRM,即高分辨率熔解曲线分析技术的TILLING筛选方法(HRM-TILLING)进行突变体筛选技术体系的探索,通过设计不同大小扩增片段引物及Mg^(2+)浓度梯度,比较了不同条件下的HRM筛选效果,结果表明当扩增片段长度为150 bp,Mg^(2+)浓度为3.0 mmol/L时,可以有效区分DNA 16倍混合池中ARF7A基因存在碱基差异的两种茄子(Solanum melongena L.)材料,建立了一套基于HRM的茄子EMS突变体TILLING技术的筛选方法。以含有2000个M2株系的茄子(EP26)EMS突变体库为材料,筛选出1个ARF7A基因和2个Pad-1基因突变体株系。本研究建立的筛选技术体系可以快速、高效地筛选茄子EMS突变体,所筛选的突变体为进一步验证、获取茄子单性结实种质及功能基因组学的研究提供研究材料。 展开更多
关键词 emS突变体 茄子 TILLING HRM 单性结实
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Central limit theolrem for linear processes generated byⅡD random variables under the sub-linear expectation 被引量:1
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作者 LIU Wei ZHANG Yong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第2期243-255,共13页
In this paper,we investigate the central limit theorem and the invariance principle for linear processes generated by a new notion of independently and identically distributed(IID)random variables for sub-linear expec... In this paper,we investigate the central limit theorem and the invariance principle for linear processes generated by a new notion of independently and identically distributed(IID)random variables for sub-linear expectations initiated by Peng[19].It turns out that these theorems are natural and fairly neat extensions of the classical Kolmogorov's central limit theorem and invariance principle to the case where probability measures are no longer additive. 展开更多
关键词 central limit theorem invariance principle ⅡD random variables sub-linear expectation linear process
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利用EMS诱变改良山栏稻地方品种株高
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作者 段吟 谢振宇 +4 位作者 周玉杰 林秋云 贺治洲 林越辉 胡伟 《热带作物学报》 北大核心 2025年第5期1124-1134,共11页
水稻(Oryza sativa L.)作为全球最重要的粮食作物之一,其产量提升对保障全球粮食安全具有重要意义。山栏稻作为我国南方地区特别是海南省中部山林地区的重要旱稻品种,因其适应性强、抗旱及抗逆性良好而广受农民喜爱,但传统山栏稻品种普... 水稻(Oryza sativa L.)作为全球最重要的粮食作物之一,其产量提升对保障全球粮食安全具有重要意义。山栏稻作为我国南方地区特别是海南省中部山林地区的重要旱稻品种,因其适应性强、抗旱及抗逆性良好而广受农民喜爱,但传统山栏稻品种普遍存在株高偏高、易倒伏及产量不稳定等问题,限制了其在现代农业中的推广应用。本研究选取五指山南对村山栏稻、黄壳山栏糯、山栏糯和山栏红4个地方山栏稻品种,采用甲基磺酸乙酯(ethyl methanesulfonate,EMS)进行诱变处理。处理后,通过M1代至M3代的筛选,选出株高降低且单株产量保持或提升的优良突变体。结果显示,4个品种通过EMS诱变均获得了多个矮化突变株,其中如五指山南对村山栏稻的WZSNDCSLD2株高降低9.6%,单株产量提升52.8%;黄壳山栏糯的HKSLN31株高降低11.5%,单株产量提升46.0%;山栏糯的SLN8株高降低15.4%,单株产量提升37.0%;山栏红的SLH6和SLH9株高分别降低22.2%和15.5%,单株产量分别提升49.6%和36.8%。这些优良突变体在总粒数、每穗颖花数、每穗实粒数、千粒重及结实率等农艺性状上亦表现出显著优势。研究表明,EMS诱变技术有效改善了山栏稻的株高及产量相关性状,为山栏稻的遗传改良和分子育种提供新的品系和理论基础。 展开更多
关键词 山栏稻 emS诱变 株高 产量 表型分析
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Parental Educational Expectations,Academic Pressure,and Adolescent Mental Health:An Empirical Study Based on CEPS Survey Data 被引量:1
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作者 Tao Xu Fangqiang Zuo Kai Zheng 《International Journal of Mental Health Promotion》 2024年第2期93-103,共11页
Background:This study aimed to investigate the relationship between parental educational expectations and adolescent mental health problems,with academic pressure as a moderating variable.Methods:This study was based ... Background:This study aimed to investigate the relationship between parental educational expectations and adolescent mental health problems,with academic pressure as a moderating variable.Methods:This study was based on the baseline data of the China Education Panel Survey,which was collected within one school year during 2013–2014.It included 19,958 samples from seventh and ninth graders,who ranged from 11 to 18 years old.After removing missing values and conducting relevant data processing,the effective sample size for analysis was 16344.The OLS(Ordinary Least Squares)multiple linear regression analysis was used to examine the relationship between parental educational expectations,academic pressure,and adolescents’mental health problems.In addition,we established an interaction term between parents’educational expectations and academic pressure to investigate the moderating effect of academic stress.Results:The study found that adolescents whose parents had high educational expectations reported less mental health problems.(β=−0.195;p<0.001).Additionally,adolescents who had high academic pressure reported more mental health problems.(β=0.649;p<0.001).Furthermore,the study found that academic pressure had a significant moderating effect on the relationship between parental educational expectations and adolescents’mental health problems(β=0.082;p<0.001).Conclusion:Parental educational expectations had a close relationship with adolescents’mental health problems,and academic pressure moderated this relationship.For those adolescents with high levels of academic pressure,the association between high parental educational expectations and mental health problems became stronger.On the contrary,for those adolescents with low levels of academic pressure,the association between high parental educational expectations and mental health problems became weaker.These findings shed new light on how parental educational expectations affected adolescent mental health problems and had significant implications for their healthy development. 展开更多
关键词 Parental educational expectations academic pressure adolescent mental health problems
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