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Upregulation of the glycine-rich protein-encoding gene GhGRPL enhances plant tolerance to abiotic and biotic stressors by promoting secondary cell wall development
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作者 Wanting Yu Yonglu Dai +17 位作者 Junmin Chen Aimin Liang Yiping Wu Qingwei Suo Zhong Chen Xingying Yan Chuannan Wang Hanyan Lai Fanlong Wang Jingyi Zhang Qinzhao Liu Yi Wang Yaohua Li Lingfang Ran Jie Xiang Zhiwu Pei Yuehua Xiao Jianyan Zeng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3311-3327,共17页
Abiotic and biotic stressors adversely affect plant survival,biomass generation,and crop yields.As the global availability of arable land declines and the impacts of global warming intensify,such stressors may have in... Abiotic and biotic stressors adversely affect plant survival,biomass generation,and crop yields.As the global availability of arable land declines and the impacts of global warming intensify,such stressors may have increasingly pronounced effects on agricultural productivity.Currently,researchers face the overarching challenge of comprehensively enhancing plant resilience to abiotic and biotic stressors.The secondary cell wall plays a crucial role in bolstering the stress resistance of plants.To increase plant resistance to stress through genetic manipulation of the secondary cell wall,we cloned a cell wall protein designated glycine-rich protein-like(GhGRPL)from cotton fibers,and found that it is specifically expressed during the period of secondary cell wall biosynthesis.Notably,this protein differs from its Arabidopsis homolog,AtGRP,since its glycine-rich domain is deficient in glycine residues.GhGRPL is involved in secondary cell wall deposition.Upregulation of GhGRPL enhances lignin accumulation and,consequently,the thickness of the secondary cell walls,thereby increasing the plant’s resistance to abiotic stressors,such as drought and salinity,and biotic threats,including Verticillium dahliae infection.Conversely,interference with GhGRPL expression in cotton reduces lignin accumulation and compromises that resistance.Taken together,our findings elucidate the role of GhGRPL in regulating secondary cell wall development through its influence on lignin deposition,which,in turn,reinforces cell wall robustness and impermeability.These findings highlight the promising near-future prospect of adopting GhGRPL as a viable,effective approach for enhancing plant resilience to abiotic and biotic stress factors. 展开更多
关键词 glycine-rich protein-like secondary cell wall abiotic stress biotic stress stress resistance
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Transcriptional regulation of secondary metabolism and autophagy genes in response to DNA replication stress in Setosphaeria turcica
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作者 MENG Ya-nan ZHANG Xin-jie +8 位作者 ZENG Fan-li ZHAI Wei-bo LI Pan HU Jing-jing XIAO Sheng-lin HAO Zhi-min CAO Zhi-yan CHEN Chuan DONG Jin-gao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第4期1068-1081,共14页
The fungal pathogen Setosphaeria turcica causes northern corn leaf blight(NCLB),which leads to considerable crop losses.Setosphaeria turcica elaborates a specialized infection structures called appressorium for maize ... The fungal pathogen Setosphaeria turcica causes northern corn leaf blight(NCLB),which leads to considerable crop losses.Setosphaeria turcica elaborates a specialized infection structures called appressorium for maize infection.Previously,we demonstrated that the S.turcica triggers an S-phase checkpoint and ATR(Ataxia Telangiectasia and Rad3 related)-dependent self-protective response to DNA genotoxic insults during maize infection.However,how the regulatory mechanism works was still largely unknown.Here,we report a genome wide transcriptional profile analysis during appressorium formation in the present of DNA replication stress.We performed RNA-Seq analysis to identify S.tuicica genes responsive to DNA replication stress.In the current work,we found that appressorium-mediated maize infection by S.turcica is significantly blocked by S-phase checkpoint.A large serial of secondary metabolite and melanin biosynthesis genes were blocked in appressorium formation of S.turcica during the replication stress.The secondary metabolite biosynthesis genes including alcohol dehydrogenase GroES-like domain,multicopper oxidase,ABCtransporter families,cytochrome P450 and FAD-containing monooxygenase were related to plant pathogen infection.In addition,we demonstrated that autophagy in S.turcica is up-regulated by ATR as a defense response to stress.We identified StATG3,StATG4,StATG5,StATG7 and StATG16 genes for autophagy were induced by ATR-mediated S-phase checkpoint.We therefore propose that in response to genotoxic stress,S.turcica utilizes ATR-dependent pathway to turn off transcription of genes governing appressorium-mediated infection,and meanwhile inducing transcription of autophagy genes likely as a mechanism of self-protection,aside from the more conservative responses in eukaryotes. 展开更多
关键词 Setosphaeria turcica APPRESSORIUM secondary metabolite AUTOPHAGY DNA replication stress
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Prevalence and Social Demographic Factors Associated with Secondary Traumatic Stress, Burnout and Compassion Satisfaction among Nurses at Selected Teaching Hospitals in Lusaka, Zambia
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作者 Michael Mumba Kanyanta Marjorie Kabinga Makukula Ruth Wahila 《Journal of Biosciences and Medicines》 CAS 2023年第2期86-104,共19页
Introduction: Nurses’ constant exposure to severe human suffering within constrained health care environments places them at risk for developing Secondary Traumatic Stress and Burnout. The current study therefore sou... Introduction: Nurses’ constant exposure to severe human suffering within constrained health care environments places them at risk for developing Secondary Traumatic Stress and Burnout. The current study therefore sought to establish the prevalence and social demographic factors associated with Secondary Traumatic Stress, Burnout and Compassion Satisfaction among Nurses working at selected Teaching Hospitals in Lusaka, Zambia. Methods: A correlational design employing a self-administered questionnaire adapted from version five of the Professional Quality of Life scale was used to collect data from 250 nurses drawn using proportional stratified sampling method. The resulting data were analyzed using version 23 of the Statistical Package for Social Sciences (SPSS). Hierarchical multiple linear regression analysis was used to identify predictors of Secondary Traumatic Stress and Burnout. Findings: Whilst the majority of respondents reported average levels of Secondary Traumatic Stress and Burnout, about a quarter reported high Secondary Traumatic Stress and Burnout scores at 23% and 26% respectively. Only 81 (32.4%) scored high on Compassion Satisfaction. Social demographic factors including;working in the main Intensive Care Unit, and being married accounted for the greatest variance in Secondary Traumatic Stress (R<sup>2</sup> = 0.237, p Conclusion: Findings of the current study signify a need to institute measures to help nurses cope with the deleterious psychological effects of constant engagement with those in distress and to foster Compassion Satisfaction. 展开更多
关键词 secondary Traumatic stress BURNOUT Compassion Satisfaction Compassion Fatigue NURSE
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Modulation of the in vitro Oxidative Stress and Erythrocyte Cell Membrane Integrity Using Aqueous, Hydroethanolic and Ethanolic Stem-Barks Extracts of Greenwayodendron suaveolens (Engl. & Diels) Verdc
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作者 Patrick Hervé Diboue Betote Moustapha Gambo Abdoulaye +6 位作者 Francis Ngolsou Esther Del Florence Ndedi Moni Adeline Sabine Fanta Yadang Fidel Castro Lah Weyepe Gabriel A. Agbor Nga Nnanga Maximilienne Ascension Nyegue 《Pharmacology & Pharmacy》 2024年第3期39-61,共23页
Pneumonia, a respiratory infection induces acute or chronic inflammation, characterized by increased activity of lymphocytes and neutrophils, thus generating oxygen-free radicals that decrease the endogenous antioxida... Pneumonia, a respiratory infection induces acute or chronic inflammation, characterized by increased activity of lymphocytes and neutrophils, thus generating oxygen-free radicals that decrease the endogenous antioxidants defence system. The aim of this experimental study focused on the capacity of nontoxic aqueous, hydroethanolic and ethanolic extracts of Greenwayodendron suaveolens (Engl. & Diels) Verdc. subsp. suaveolens to regulate free reactive species and protein inflammation generated by infectious disease. The phytochemical screenings of G. suaveolens extracts were carried out according to precipitation and colorimetric methods. The total antioxidant and flavonoid contents were determined by the Folin-Ciocalteu and Aluminium Chloride ethanolic methods. The efficiency of G. suaveolens extracts on free radicals was evaluated using DPPH<sup>•</sup>, ABTS<sup>+•</sup>, and FRAP methods. The anti-inflammatory properties of extracts were evaluated according to in vitro protein (BSA) denaturation, Proteinase Inhibitory Action, and Red Blood Cell Membrane stabilization assays. The G. suaveolens aqueous, hydroethanolic and ethanolic extracts were used for the acute toxicity assessment according to the OECD protocol. The obtained results showed the presence of flavonoids, phenols, polyphenols, tannins, anthocyanins, alkaloids, terpenoids, and sterols as secondary metabolites families in G. suaveolens extracts. The highest contents of total antioxidants and flavonoids were highlighted in the hydroethanolic extract. However, it’s the G. suaveolens aqueous extract that showed the best free radical DPPH<sup>•</sup> and ABTS<sup>+•</sup> scavenging activities (SC<sub>50</sub>) of 11.06 μg/mL and 15.16 μg/mL respectively. The highest ferric-reducing activity was found in G. suaveolens ethanolic extract with 866.23 μg EGA/mg of dry weight. The hydroethanolic extract has shown a high anti-inflammatory activity through BSA denaturation and erythrocyte membrane haemolysis with inhibitory concentrations 50 (IC<sub>50</sub>) of 48.63 and 59.22 μg/mL respectively. In contrast, proteinase inhibitory activity revealed a better potential of IC<sub>50</sub> (34.19 μg/mL) for the ethanolic extract. In oral acute toxicity, all treated groups revealed neither mortality nor any significant alteration in behaviour and locomotion. The lethal dose 50 (LD<sub>50</sub>) of G. suaveolens extracts was >5000 mg/kg. These results suggest that G. suaveolens stem-barks extracts may serve as therapeutic sources to prevent inflammation induced by oxidative stress, an important feature of infectious diseases. 展开更多
关键词 Greenwayodendron suaveolens secondary Metabolites Oxidative stress Antioxidant Activity Anti-Inflammatory Properties and Oral Acute Toxicity
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Inhibition of endoplasmic reticulum stress alleviates secondary injury after traumatic brain injury 被引量:9
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作者 Hong-Ping Tan Qiang Guo +2 位作者 Gang Hua Jun-Xi Chen Jun-Chao Liang 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第5期827-836,共10页
Apoptosis after traumatic brain injury has been shown to be a major factor influencing prognosis and outcome. Endoplasmic reticulum stress may be involved in mitochondrial mediated neuronal apoptosis. Therefore, endop... Apoptosis after traumatic brain injury has been shown to be a major factor influencing prognosis and outcome. Endoplasmic reticulum stress may be involved in mitochondrial mediated neuronal apoptosis. Therefore, endoplasmic reticulum stress has become an important mechanism of secondary injury after traumatic brain injury. In this study, a rat model of traumatic brain injury was established by lateral fluid percussion injury. Fluorescence assays were used to measure reactive oxygen species content in the cerebral cortex. Western blot assays were used to determine expression of endoplasmic reticulum stress-related proteins. Hematoxylin-eosin staining was used to detect pathological changes in the cerebral cortex. Transmission electron microscopy was used to measure ultrastructural changes in the endoplasmic reticulum and mitochondria. Our results showed activation of the endoplasmic reticulum stress-related unfolded protein response. Meanwhile, both the endoplasmic reticulum stress response and mitochondrial apoptotic pathway were activated at different stages post-traumatic brain injury. Furthermore, pretreatment with the endoplasmic reticulum stress inhibitor, salubrinal(1 mg/kg), by intraperitoneal injection 30 minutes before injury significantly inhibited the endoplasmic reticulum stress response and reduced apoptosis. Moreover, salubrinal promoted recovery of mitochondrial function and inhibited activation of the mitochondrial apoptotic pathway post-traumatic brain injury. These results suggest that endoplasmic reticulum stress might be a key factor for secondary brain injury post-traumatic brain injury. 展开更多
关键词 nerve regeneration traumatic brain injury endoplasmic reticulum stress APOPTOSIS MITOCHONDRIA reactive oxygen species unfolded protein response secondary brain injury salubrinal neural regeneration
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Effects of Barium Stress in Brassica juncea and Cakile maritima:The Indicator Role of Some Antioxidant Enzymes and Secondary Metabolites 被引量:2
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作者 Houda Bouslimi Renata Ferreira +4 位作者 Nesrine Dridi Pedro Brito Susete Martins-Dias Isabel Caçador Noomene Sleimi 《Phyton-International Journal of Experimental Botany》 SCIE 2021年第1期145-158,共14页
Soil contamination by toxic trace metal elements,like barium(Ba),may stimulate various undesirable changes in the metabolic activity of plants.The plant responses are fast and with,direct or indirect,generation of rea... Soil contamination by toxic trace metal elements,like barium(Ba),may stimulate various undesirable changes in the metabolic activity of plants.The plant responses are fast and with,direct or indirect,generation of reactive oxygen species(ROS).To cope with the stress imposed by the ROS production,plants developed a dual cellular system composed of enzymatic and non-enzymatic players that convert ROS,and their by-products,into stable nontoxic molecules.To assess the Ba stress response of two Brassicaceae species(Brassica juncea,a glycophyte,and Cakile maritime,a halophyte),plants were exposure to different Ba concentrations(0,100,200,300 and 500µM).The plants response was evaluated through their morphology and development,the determination of plant leaves antioxidant enzymatic activities and by the production of plants secondary metabolites.Results indicated that the two Brassicaceae species have the ability to survive in an environment containing Ba(even at 500µM).The biomass production of C.maritima was slightly affected whereas an increase in biomass B.juncea was noticed.The stress imposed by Ba activated the antioxidant defense system in the two species,noticed by the changes in the leaves activity of catalase(CAT),ascorbate peroxidase(APX)and guaicol peroxidase(GPX),and of the secondary metabolites,through the production of total phenols and flavonoids.The enzymatic response was not similar within the two plant species:CAT and APX seem to have a more important role against the oxidative stress in C.maritima while in B.juncea is GPX.Overall,total phenols and flavonoids production was more significant in the plants aerial part than in the roots,of the both species.Although the two Brassicaceae species response was different,in both plants catalytic and non-catalytic transformation of ROS occurs,and both were able to overcome the Ba toxicity and prevent the cell damage. 展开更多
关键词 Brassica juncea Cakile maritima antioxidant enzymes barium stress oxidative stress secondary metabolites
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Effects of Waterlogging Stress on the Physiological Characteristics and Secondary Metabolites of Herbaceous Peony (<i>Paeonia lactiflora</i>Pall.) 被引量:1
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作者 Minmin Liu Qingxia Zhang +4 位作者 Jinguang Xu Mingyue Bao Dongliang Zhang Anqi Xie Xia Sun 《American Journal of Plant Sciences》 2021年第4期536-557,共22页
Herbaceous peony is an ornamental plant with medicinal properties. Waterlogging can affect its yield and quality as it grows and matures. In this study, we subjected “Taohuafeixue”, “Yangfeichuyu” and “Hongxiuqiu... Herbaceous peony is an ornamental plant with medicinal properties. Waterlogging can affect its yield and quality as it grows and matures. In this study, we subjected “Taohuafeixue”, “Yangfeichuyu” and “Hongxiuqiu” herbaceous peony varieties to a simulated waterlogging stress treatment and investigated the effects of waterlogging on their physiological characteristics and the secondary metabolite contents in their leaves and roots. Short-term waterlogging caused the leaves to turn yellow or red and the roots to turn black. The stele and the cell wall of the endothelial cells thickened, and the cortical cells enlarged. Waterlogging did not significantly change plant height, leaf length, <span style="font-family:Verdana;">and leaf area;however, it significantly decreased the root-shoot ratio of</span><span style="font-family:Verdana;"> “Yang</span><span style="font-family:Verdana;">feichuyu” and “Hongxiuqiu” varieties. The activity of antioxidant enzymes</span><span style="font-family:Verdana;"> and the content of osmotic regulators increased under waterlogging. After short-</span><span style="font-family:Verdana;">term waterlogging stress treatment, the content of paeoniflorin and albiflorin increased in the roots of “Taohuafeixue” and “Yangfeichuyu”, and the content of benzoylpaeoniflorin increased in the root of “Hongxiuqiu”</span><span style="font-family:Verdana;">.</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> The content of gallic acid and total flavonoids increased in the leaves of “Taohuafeixue” and “Yangfeichuyu”. After the waterlogging, paeoniflorin and benzoylpaeoniflorin increased in the </span><span style="font-family:Verdana;">autumn root of “Hongxiuqiu”.</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">This study expands our knowledge about the medicinal properties of herbaceous peony and informs about its production and cultivation under waterlogged conditions.</span> 展开更多
关键词 Waterlogging stress secondary Metabolism Herbaceous Peony Antioxidant Enzymes Osmotic Regulation MICROSTRUCTURE
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Factors Associated with Secondary Traumatic Stress among Emergency Nurses: An Integrative Review 被引量:1
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作者 Hamza F. Ratrout Ayman M. Hamdan-Mansour 《Open Journal of Nursing》 2017年第11期1209-1226,共18页
Background: Emergency nurses are exposed to traumatized patients as part of their job. Secondary exposure to trauma may lead to traumatic stress similar to those experienced by the primary victim. Emergency nurses dev... Background: Emergency nurses are exposed to traumatized patients as part of their job. Secondary exposure to trauma may lead to traumatic stress similar to those experienced by the primary victim. Emergency nurses develop secondary traumatic stress symptoms more than other nurses due to nature of emergency departments. The consequences of secondary traumatic stress can be noticed at personal, interpersonal, or organizational level. Objectives: This integrative review aimed to explore the literature on the factors attenuate or enhance occurrence of secondary traumatic stress among emergency nurses, to identify these factors, and to provide recommendations for research in the field. Method: An integrative literature review of quantitative and qualitative studies on secondary traumatic stress in emergency nurses were published in English language between 2000 and 2017 through the following data bases: Cumulative Index to Nursing and Allied Health Literature (CINAHL), ProQuest, Medline, PubMed, Google Scholar, SAGE Journals, Wiley on Line Library, Science Direct and EBSCOhost Sources. Results: The review identified that factors associated with secondary traumatic stress can be classified into personal and organizational factors. Findings on personal factors such as age, gender, and experience are controversial, whereas organizational factors such as trauma case load and perceived organizational support were found to predict traumatic stress more than the personal factors. Conclusions: Emergency nurses are at risk to develop traumatic stress and need to be aware to the contributing factors in order to maintain their well being. Further research is required to explore the factors enhance or attenuate occurrence of secondary traumatic stress. 展开更多
关键词 secondary TRAUMATIC stress EMERGENCY Nurses FACTORS INTEGRATIVE Review
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Self-Compassion and Empathy: Impact on Burnout and Secondary Traumatic Stress in Medical Training 被引量:1
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作者 David A. Richardson Sara Jaber +3 位作者 Sarah Chan Michelle T. Jesse Hareena Kaur Roopina Sangha 《Open Journal of Epidemiology》 2016年第3期161-166,共6页
Objective: To determine how self-compassion and empathy might influence the degree of burnout, secondary traumatic stress and compassion satisfaction among medical students and residents. Methods: Cross-sectional surv... Objective: To determine how self-compassion and empathy might influence the degree of burnout, secondary traumatic stress and compassion satisfaction among medical students and residents. Methods: Cross-sectional survey of medical students and select residency programs at Henry Ford Hospital in Detroit, Michigan. Respondents completed the Professional Quality of Life Scale (burnout, secondary traumatic stress and compassion satisfaction), Neff’s Self-Compassion Scale, and the empathic concern and personal distress subscales of the Interpersonal Reactivity Index. Results: The response rate was 28.6%. 23.9% and 27.3% of medical trainees reported high levels of burnout and secondary traumatic stress, respectively. Females reported greater empathy but lower self-compassion than males. Greater concern for others and oneself and lower personal distress predicted greater pleasure derived from professional work. Less concern for others and lower concern for oneself predicted greater burnout. Conclusions: Compassion for oneself and for others within their care appears to ameliorate burnout and can increase professional satisfaction. Initiatives to foster empathy and self-compassion may enhance individual well-being. 展开更多
关键词 BURNOUT secondary Traumatic stress EMPATHY SELF-COMPASSION WELL-BEING
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Triaxial creep damage characteristics of sandstone under high crustal stress and its constitutive model for engineering application 被引量:1
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作者 Dongxu Chen Laigui Wang +1 位作者 Pierre Darry Versaillot Chuang Sun 《Deep Underground Science and Engineering》 2023年第3期262-273,共12页
The creep characteristics of rock under high crustal stress are of important influence on the long‐term stability of deep rock engineering.To study the creep characteristics and engineering application of sandstone u... The creep characteristics of rock under high crustal stress are of important influence on the long‐term stability of deep rock engineering.To study the creep characteristics and engineering application of sandstone under high crustal stress,this study constructed nonlinear creep damage(NCD)constitutive mode based on the triaxial graded loading‒unloading creep test of sandstone in the Yuezhishan Tunnel.A numerical NCD constitutive model and a breakable lining(BL)model were developed based on FLAC3D and then applied to the stability analysis of the Yuezhishan Tunnel.Based on the creep test results of sandstone,a power function of creep rate and stress level was constructed,by which the long‐term strength was solved.The results show that the long‐term strength of the red sandstone based on the related function of the steady‐state creep rate and stress level is close to the measured stress value in engineering.The NCD model considering damage factors reflects the instantaneous and viscoelastic plasticity deformation characteristics of the red sandstone.The numerical NCD constitutive model and the BL model can reflect surrounding rock deformation characteristics and lining failure characteristics in practical engineering.The research results provide theoretical references for long‐term stability analysis of rock engineering and the deformation control of surrounding rock under high crustal stress. 展开更多
关键词 creep damage model high stress long‐term strength secondary development tunnel engineering
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Secondary Stress State around the Bored Hole in Salt Strata
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作者 Mihaela Toderas 《Journal of Geological Resource and Engineering》 2014年第2期111-114,共4页
In Romania, rendering the oil structures evident in the deep strata (= 6,000 m) is conditioned by the penetration of some salt deposits of appreciable thickness (500-3,000 m) situated above the structures with pet... In Romania, rendering the oil structures evident in the deep strata (= 6,000 m) is conditioned by the penetration of some salt deposits of appreciable thickness (500-3,000 m) situated above the structures with petroleum potential. Crossing by the drilling of these salt deposits constitutes a major risk factor both in achievement (drilling, cementing) and afterwards, to ensure the stability-reliability of the wells. Based on these reasons, the researches have been focused on: the study of salt behavior deformation, establishment of the required parameters to ensure the stability of the drillings until the bore-hole lining (especially the secondary stress state around the drilling, the density of the drilling fluid in correlation with the temperature and respectively the depth) and also after casing (type of the cement pastes, the nature, the quality and the dimensions of pipes), namely the reliability of the wells. 展开更多
关键词 SALT stability secondary stress state DRILLING pipe cement paste temperature depth.
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Reflection:A Critical Look at Escaping Secondary Traumatic Stress Experienced by Law Enforcement Officers
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作者 James C.Shumpert Frederick M.G.Evans 《Journal of Literature and Art Studies》 2021年第4期260-270,共11页
Despite the stigma that is associated with law enforcement officers receiving mental health resources and treatment to combat secondary traumatic stress,it is widely the most effective form for recovery and having a f... Despite the stigma that is associated with law enforcement officers receiving mental health resources and treatment to combat secondary traumatic stress,it is widely the most effective form for recovery and having a fulfilling career.Law enforcement officers are superheroes and,they are known for saving the day.That is why it is critical for mental health offerings to be normalized in law enforcement agencies and constant evaluation of the psychological and cognitive well-being of officers.Unfortunately,the stress of the profession will not go away,but having resources and incentives to address several factors that officers face will assist with their overall feeling about the important work they do.As such,it is recommended that law enforcement agencies adopt programs to treat secondary traumatic stress,such as Critical Incident Stress Debriefing,Peer-Support Program,and Crisis Intervention Team.While there is no perfect program,these programs are designed to reduce the risk of serious injury or death during an emergency interaction between citizens and law enforcement officers.Ultimately,it is the responsibility of those charged with protecting law enforcement officers to understand the stress and how it affects the mind and body of those officers in managing life,work,and citizens. 展开更多
关键词 secondary traumatic stress mental health stress critical incident stress crisis intervention
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江苏省高年资护士共情疲劳的潜在类别分析 被引量:2
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作者 曾丽华 陈娴 +3 位作者 朱珠 孙翠华 吴金凤 乔成平 《护理学杂志》 CSCD 北大核心 2024年第2期64-68,共5页
目的了解江苏省高年资护士共情疲劳的现状及潜在类别,分析其影响因素,为高年资护士的人本化管理提供参考。方法采用便利抽样法,选取江苏省苏中、苏南、苏北地区护理工作年限≥10年的高年资护士3509人作为研究对象,采用一般资料调查表、... 目的了解江苏省高年资护士共情疲劳的现状及潜在类别,分析其影响因素,为高年资护士的人本化管理提供参考。方法采用便利抽样法,选取江苏省苏中、苏南、苏北地区护理工作年限≥10年的高年资护士3509人作为研究对象,采用一般资料调查表、中文版共情疲劳量表及中文版护士工作环境感知量表进行调查。结果高年资护士职业倦怠得分为(24.58±6.50)分,继发性创伤应激得分为(26.80±6.07)分,同情满足得分为(36.57±7.38)分。中度及以上共情疲劳者为2386人(68.0%)。潜在剖面分析显示,共情疲劳分为共情疲劳优势组(32.00%)、中度共情疲劳组(63.12%)和共情疲劳应激组(4.87%)3个潜在类别。logistic回归分析显示,职务、月收入、班次、对工作环境感知是共情疲劳不同潜在类别的影响因素(均P<0.05)。结论高年资护士共情疲劳存在3个潜在类别,呈现群体异质性。护理管理者需采用多元化、人本化管理策略,激发高年资护士工作热情,降低共情疲劳水平。 展开更多
关键词 护士 高年资 共情疲劳 职业倦怠 继发性创伤应激 工作环境感知 潜在类别分析 护理管理
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接种丛枝菌根真菌对盐胁迫下月见草生理及次生代谢产物的影响
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作者 王非 董晨肖 张玉红 《东北林业大学学报》 CAS CSCD 北大核心 2024年第10期110-118,共9页
以月见草为试验材料,进行盆栽试验。采取双因素试验设计,设置无NaCl对照和150 mmol/L NaCl胁迫处理以及分别接种幼套近明球囊霉(Claroideoglomus etunicatum)、摩西斗管囊霉(Funnelifor mismosseae)、根内根孢囊霉(Rhizophagus intrarad... 以月见草为试验材料,进行盆栽试验。采取双因素试验设计,设置无NaCl对照和150 mmol/L NaCl胁迫处理以及分别接种幼套近明球囊霉(Claroideoglomus etunicatum)、摩西斗管囊霉(Funnelifor mismosseae)、根内根孢囊霉(Rhizophagus intraradices)和不接种丛枝菌根真菌(AMF)处理,研究接种不同的AMF对盐胁迫下月见草的生长、生理以及次生代谢产物的影响,以期为增强月见草的耐盐性提供新方法。结果表明:盐胁迫下,与未接种AMF的月见草相比,接种AMF的月见草的株高、根长、基径、地上干质量和地下干质量均显著提高,同时,月见草叶片的叶绿素、可溶性糖、可溶性蛋白、脯氨酸、总黄酮和总酚的质量分数均显著提高,此外,净光合速率和抗氧化酶活性也显著增强,然而,丙二醛质量摩尔浓度显著降低。说明接种AMF可以提高盐胁迫下月见草的光合能力和渗透调节能力,增加抗氧化酶活性,促进次生代谢产物的积累,从而促进其生长发育。综合月见草的各个指标发现,接种AMF能够提高月见草的抗盐能力,不同AMF对月见草耐盐性的提升效果不同。其中以接种根内根孢囊霉对提高月见草耐盐性的效果最为显著,摩西斗管囊霉次之,幼套近明球囊霉的效果较差。 展开更多
关键词 月见草 丛枝菌根真菌 盐胁迫 次生代谢产物
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新型沙漏形隔磁结构的主副齿式永磁游标电机的设计与分析
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作者 谢颖 张燚 +2 位作者 杨帆 王泽兵 齐国良 《电机与控制学报》 EI CSCD 北大核心 2024年第8期115-123,134,共10页
基于传统交替极双定子分裂齿式永磁游标电机的拓扑结构提出一种新型沙漏形隔磁结构的主副齿式永磁游标电机,旨在进一步提高电机转矩密度和解决永磁体极间漏磁的问题。依据磁场调制原理,首先对定子主齿和副齿的结构参数进行优化设计,主... 基于传统交替极双定子分裂齿式永磁游标电机的拓扑结构提出一种新型沙漏形隔磁结构的主副齿式永磁游标电机,旨在进一步提高电机转矩密度和解决永磁体极间漏磁的问题。依据磁场调制原理,首先对定子主齿和副齿的结构参数进行优化设计,主齿的调节作用使低速旋转永磁体磁场和高速旋转电枢磁场进行耦合,副齿对气隙磁场进一步调节产生其他次有效谐波增加电机的同步转矩分量。在永磁体两侧引入沙漏形隔磁结构,该结构不仅抑制极间泄漏,而且大大降低永磁体径向应力和径向形变;并探究永磁体极弧系数对转矩及功率因数的影响,确定优化设计后的模型参数。最后用有限元仿真结果验证了沙漏形隔磁结构的主副齿式永磁游标电机的优越性,相较于传统的分裂齿式永磁游标电机,该电机具有更大的转矩和更小的转矩脉动。 展开更多
关键词 游标电机 主副齿 转矩密度 转子应力 功率因数 沙漏形隔磁
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K型井架悬挂机械手二层台结构设计与测试
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作者 周兆明 刘睿 +2 位作者 杨忠祖 刘梦 李岩 《中国测试》 CAS 北大核心 2024年第2期85-90,116,共7页
钻机井架上的二层台增加悬挂式机械手可以提高钻采效率,但会导致二层台整体受力增大,而传统井架二层台结构设计时未考虑增加悬挂式机械手,需要改进其结构,提高二层台承载能力以满足加装二层台机械手后的井架整体承载要求。在现有二层台... 钻机井架上的二层台增加悬挂式机械手可以提高钻采效率,但会导致二层台整体受力增大,而传统井架二层台结构设计时未考虑增加悬挂式机械手,需要改进其结构,提高二层台承载能力以满足加装二层台机械手后的井架整体承载要求。在现有二层台结构基础上,对普通井架二层台改进结构设计,优化力学结构,强化二层台承载性能,用Ansys软件对该设计模型进行了数值计算和结构分析。利用STS-WiFi无线结构测试系统对优化结构后的二层台进行现场应变测试,通过砝码施加阶梯载荷并实时监测二层台关键测试点的应力变化。整理分析测试数据并将现场测试结果与理论计算结果比较,研究表明现场测试结果与理论计算结果相吻合,该增加悬挂式机械手的二层台结构设计满足强度要求,可用于钻采作业。 展开更多
关键词 井架二层台 结构优化 有限元分析 应力测试
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非对称变位斜齿轮参数化建模和接触应力分析
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作者 林家祥 招远聪 +1 位作者 付学中 徐海军 《机械传动》 北大核心 2024年第6期117-123,共7页
为构建非对称渐开线变位斜齿轮精确模型并分析压力角对其接触应力的影响,根据齿轮啮合原理以及C#对SolidWorks二次开发,建立了从齿条刀具展成非对称渐开线变位斜齿轮的数学模型以及精确的实体模型;同时,采用有限元法分析其齿面接触应力... 为构建非对称渐开线变位斜齿轮精确模型并分析压力角对其接触应力的影响,根据齿轮啮合原理以及C#对SolidWorks二次开发,建立了从齿条刀具展成非对称渐开线变位斜齿轮的数学模型以及精确的实体模型;同时,采用有限元法分析其齿面接触应力,并与传统公式法计算的对称变位斜齿轮齿面接触应力进行了比较。研究表明,当一侧齿面压力角相同时,非对称变位斜齿轮一侧齿面接触应力与对称变位斜齿轮十分接近,接触应力随压力角变化的增减趋势基本一致,说明了非工作侧齿面压力角的变化对工作侧齿面接触应力的影响并不明显。因此,用来计算对称变位斜齿轮齿面接触应力的传统公式法同样可以近似计算非对称变位斜齿轮的齿面接触应力。该方法可为非对称渐开线变位斜齿轮的设计提供参考。 展开更多
关键词 非对称齿轮 变位齿轮 数学模型 SOLIDWORKS二次开发 接触应力分析
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盐胁迫对杠柳幼苗生长及次生代谢产物积累的影响 被引量:3
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作者 韩翠婷 李先宽 +2 位作者 王广苹 马琳 张坚 《西北植物学报》 CAS CSCD 北大核心 2024年第2期280-287,共8页
【目的】探索盐胁迫对杠柳幼苗生长及次生代谢物的影响,初步了解杠柳盐耐受范围及盐胁迫对杠柳次生代谢产物的诱导作用。【方法】以培养30 d的杠柳实生苗为材料,测定不同盐浓度[0(CK)、0.2%、0.5%、1.0%、2.0%]处理后,杠柳幼苗的生物量... 【目的】探索盐胁迫对杠柳幼苗生长及次生代谢物的影响,初步了解杠柳盐耐受范围及盐胁迫对杠柳次生代谢产物的诱导作用。【方法】以培养30 d的杠柳实生苗为材料,测定不同盐浓度[0(CK)、0.2%、0.5%、1.0%、2.0%]处理后,杠柳幼苗的生物量及总甾体成分、强心苷类成分(杠柳毒苷、杠柳次苷及杠柳苷元)、4-甲氧基水杨醛含量的变化特征。【结果】杠柳幼苗在中低浓度盐胁迫下生长良好,且地上部分干鲜质量及地下部分干质量均有不同程度增加,其干湿比也均随盐胁迫程度的增加逐渐升高;植株体内的主要有效成分如总甾体、强心苷类的含量在中等盐胁迫浓度作用下呈现明显上升趋势,而4-甲氧基水杨醛含量则在高浓度盐胁迫下显著增加。【结论】杠柳具有较强的耐盐性,且一定浓度范围内的盐胁迫可显著提高杠柳幼苗根、茎中主要药效成分含量。 展开更多
关键词 杠柳 盐胁迫 生物量 次生代谢产物
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基于ABAQUS的蒙皮拉形仿真与二次开发技术研究
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作者 魏巍 段鑫龙 李小强 《新技术新工艺》 2024年第10期46-50,共5页
针对有限元批量仿真中建模繁琐的问题,结合蒙皮拉伸成形工艺和蒙皮拉形有限元模型的特点,基于ABAQUS/Python进行二次开发,快速实现不同工况条件下有限元仿真。首先分析了拉伸成形工艺以明确有限元仿真的过程和影响拉形效果的工况参数,... 针对有限元批量仿真中建模繁琐的问题,结合蒙皮拉伸成形工艺和蒙皮拉形有限元模型的特点,基于ABAQUS/Python进行二次开发,快速实现不同工况条件下有限元仿真。首先分析了拉伸成形工艺以明确有限元仿真的过程和影响拉形效果的工况参数,建立蒙皮拉形有限元模型,包括建立几何模型、确定蒙皮材料、定义拉伸轨迹等。研究了基于Python的ABAQUS二次开发,建立了蒙皮拉形仿真结果批量生成插件,利用插件可以对预拉伸量、包覆过程延伸量和摩擦系数等工艺参数进行自动或手动修改,实现了有限元仿真模型的批量仿真和计算结果自动保存,同时将仿真数据转换为可自由读取的格式,方便进一步的数据分析与利用,有效简化繁琐的建模步骤,提高蒙皮拉形研究过程中有限元批量分析的效率。 展开更多
关键词 飞机蒙皮 拉伸成形 有限元仿真 二次开发 Python脚本 应力数据集
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不同加载速率及应力路径对饱和红黏土的力学响应
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作者 吴建奇 陈腾 《路基工程》 2024年第5期51-56,共6页
利用ABAQUS有限元软件,建立轴对称模型,分析赣南地区的红黏土在不同加载速率及应力路径下的力学响应,并验证数值模型的可行性。结果表明:不同应力路径下红黏土的应力-应变关系曲线、孔压-应变关系曲线变化特征不同,同一应力路径下加载... 利用ABAQUS有限元软件,建立轴对称模型,分析赣南地区的红黏土在不同加载速率及应力路径下的力学响应,并验证数值模型的可行性。结果表明:不同应力路径下红黏土的应力-应变关系曲线、孔压-应变关系曲线变化特征不同,同一应力路径下加载速率的大小不影响整体发展趋势,但决定峰值大小;红黏土对侧向卸荷的敏感性高于轴向加载,高加载速率的敏感性大于低加载速率;三种应力路径下的孔压-加载速率关系曲线,均可用对数函数关系描述。 展开更多
关键词 红黏土 应力路径 加载速率 有限元分析 二次开发
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