Numerous environmental and endogenous signals control the highly orchestrated and intricate process of plant senescence.Ethylene,a well-known inducer of senescence,has long been considered a key endogenous regulator o...Numerous environmental and endogenous signals control the highly orchestrated and intricate process of plant senescence.Ethylene,a well-known inducer of senescence,has long been considered a key endogenous regulator of leaf and flower senescence,but the molecular mechanism of ethylene-induced ovule senescence has not yet been elucidated.In this study,we found that blockage of fertilization caused ovule abortion in the pear cultivar‘1913’.According to transcriptome and phytohormone content data,ethylene biosynthesis was activated by pollination.At the same time,ethylene overaccumulated in ovules,where cells were sensitive to ethylene signals in the absence of fertilization.We identified a transcription factor in the ethylene signal response,ethylene-insensitive 3-like(EIL1),as a likely participant in ovule senescence.Overexpression of PbEIL1 in tomato caused precocious onset of ovule senescence.We further found that EIL1 could directly bind to the promoter of the SENESCENCE-ASSOCIATED CYSTEINE PROTEINASE 1(PbCysp1)gene and act upstream of senescence.Yeast one-hybrid and dual-luciferase assays revealed the interaction of the transcription factor and the promoter DNA sequence and demonstrated that PbEIL1 enhanced the action of PbCysp1.Collectively,our results provide new insights into how ethylene promotes the progression of unfertilized ovule senescence.展开更多
Objectives:The purpose of the study was to investigate the nursing students'levels of the knowledge,willingness,and attitudes toward first aid behavior as bystanders in road traffic accident and the related factor...Objectives:The purpose of the study was to investigate the nursing students'levels of the knowledge,willingness,and attitudes toward first aid behavior as bystanders in road traffic accident and the related factors.Methods:A total of 475 nursing students were recruited by convenience choosing in Tianjin University of Traditional Chinese Medicine.The nursing students'self-efficacy,core self-evaluation,knowledge,willingness and attitudes toward first aid behavior as bystanders in traffic accidents were investigated with a self-designed questionnaire.Results:The scores of knowledge,willingness,and attitudes toward first aid behavior in traffic accident trauma were 7.51±1.93,15.54±5.03,and 7.73±1.56,respectively.Students who once gained training of first aid showed lower levels of attitude toward first aid behavior than those untrained(t=-2.345,P=0.019).It was found that self-efficacy was correlated to the knowledge(r=0.150,P<0.001),willingness(r=0.182,P<0.004)and attitudes toward behavior of the first aid(r=0.371,P<0.001)among nursing students.Core self-evaluation was correlated to knowledge(r=0.193,P<0.001)and attitudes toward behavior of the first aid(r=0.199,P<0.001).Conclusions:The first aid knowledge among nursing students was not satisfactory.The study suggested that an unsustainable short first-aid training program may bring negative effects.Countermeasures should be taken to ensure both quality and continuity of first aid training.Meanwhile,more attention should be paid to improving the self-efficacy and core self-evaluation of the nursing students.展开更多
基金the National Key R&D Program of China(2019YFD1001400)the China Agriculture Research System(CARS 28-45).
文摘Numerous environmental and endogenous signals control the highly orchestrated and intricate process of plant senescence.Ethylene,a well-known inducer of senescence,has long been considered a key endogenous regulator of leaf and flower senescence,but the molecular mechanism of ethylene-induced ovule senescence has not yet been elucidated.In this study,we found that blockage of fertilization caused ovule abortion in the pear cultivar‘1913’.According to transcriptome and phytohormone content data,ethylene biosynthesis was activated by pollination.At the same time,ethylene overaccumulated in ovules,where cells were sensitive to ethylene signals in the absence of fertilization.We identified a transcription factor in the ethylene signal response,ethylene-insensitive 3-like(EIL1),as a likely participant in ovule senescence.Overexpression of PbEIL1 in tomato caused precocious onset of ovule senescence.We further found that EIL1 could directly bind to the promoter of the SENESCENCE-ASSOCIATED CYSTEINE PROTEINASE 1(PbCysp1)gene and act upstream of senescence.Yeast one-hybrid and dual-luciferase assays revealed the interaction of the transcription factor and the promoter DNA sequence and demonstrated that PbEIL1 enhanced the action of PbCysp1.Collectively,our results provide new insights into how ethylene promotes the progression of unfertilized ovule senescence.
基金The study was supported by the Key Cultivated Academic Construction Project of State Administrative Bureau for prophylactic medicine of Traditional Chinese Medicine(No.2012[170])Tianjin College Students'Innovation and Entrepreneurship Training Program(No.201510063040)
文摘Objectives:The purpose of the study was to investigate the nursing students'levels of the knowledge,willingness,and attitudes toward first aid behavior as bystanders in road traffic accident and the related factors.Methods:A total of 475 nursing students were recruited by convenience choosing in Tianjin University of Traditional Chinese Medicine.The nursing students'self-efficacy,core self-evaluation,knowledge,willingness and attitudes toward first aid behavior as bystanders in traffic accidents were investigated with a self-designed questionnaire.Results:The scores of knowledge,willingness,and attitudes toward first aid behavior in traffic accident trauma were 7.51±1.93,15.54±5.03,and 7.73±1.56,respectively.Students who once gained training of first aid showed lower levels of attitude toward first aid behavior than those untrained(t=-2.345,P=0.019).It was found that self-efficacy was correlated to the knowledge(r=0.150,P<0.001),willingness(r=0.182,P<0.004)and attitudes toward behavior of the first aid(r=0.371,P<0.001)among nursing students.Core self-evaluation was correlated to knowledge(r=0.193,P<0.001)and attitudes toward behavior of the first aid(r=0.199,P<0.001).Conclusions:The first aid knowledge among nursing students was not satisfactory.The study suggested that an unsustainable short first-aid training program may bring negative effects.Countermeasures should be taken to ensure both quality and continuity of first aid training.Meanwhile,more attention should be paid to improving the self-efficacy and core self-evaluation of the nursing students.
