Upregulation of the glycine-rich protein-encoding gene GhGRPL enhances plant tolerance to abiotic and biotic stressors by promoting secondary cell wall development

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.

Inhibition of endoplasmic reticulum stress alleviates secondary injury after traumatic brain injury

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.

Effects of Barium Stress in Brassica juncea and Cakile maritima:The Indicator Role of Some Antioxidant Enzymes and Secondary Metabolites

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.

Effects of Waterlogging Stress on the Physiological Characteristics and Secondary Metabolites of Herbaceous Peony (<i>Paeonia lactiflora</i>Pall.)

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, and leaf area;however, it significantly decreased the root-shoot ratio of “Yangfeichuyu” and “Hongxiuqiu” varieties. The activity of antioxidant enzymes and the content of osmotic regulators increased under waterlogging. After short-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”. 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 autumn root of “Hongxiuqiu”. This study expands our knowledge about the medicinal properties of herbaceous peony and informs about its production and cultivation under waterlogged conditions.

Factors Associated with Secondary Traumatic Stress among Emergency Nurses: An Integrative Review

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.

Self-Compassion and Empathy: Impact on Burnout and Secondary Traumatic Stress in Medical Training

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.

Transcriptional regulation of secondary metabolism and autophagy genes in response to DNA replication stress in Setosphaeria turcica

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.

Prevalence and Social Demographic Factors Associated with Secondary Traumatic Stress, Burnout and Compassion Satisfaction among Nurses at Selected Teaching Hospitals in Lusaka, Zambia

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 (R2 = 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.

Secondary Stress State around the Bored Hole in Salt Strata

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.

Reflection:A Critical Look at Escaping Secondary Traumatic Stress Experienced by Law Enforcement Officers

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.

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

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•, ABTS+•, 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• and ABTS+• scavenging activities (SC50) 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 (IC50) of 48.63 and 59.22 μg/mL respectively. In contrast, proteinase inhibitory activity revealed a better potential of IC50 (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 (LD50) 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.

针刺联合神经干细胞修复脊髓损伤的科学依据

背景:脊髓损伤是由创伤性或非创伤性事件引起的一种神经系统疾病,常导致损伤节段以下严重功能障碍。近年来,神经干细胞移植被认为在调控脊髓损伤后的炎症反应、抑制胶质瘢痕的过度增生以及促进神经再生方面具有显著的治疗潜力。目的:综述并讨论针刺及神经干细胞移植疗法在抑制脊髓损伤诱导的继发性损伤中的潜在作用机制,深入探讨其治疗脊髓损伤的科学依据。方法:以“脊髓损伤,针刺,神经干细胞,SDF-1α/CXCR4轴”为中文检索词,以“Spinal cord injury,acupuncture,neural stem cells,SDF-1α/CXCR4 axis”为英文检索词,分别检索PubMed、Elsevier、万方及中国知网数据库,最终纳入96篇文献,汇总分析了针刺联合神经干细胞治疗脊髓损伤的相关研究成果,总结了这一联合疗法在治疗脊髓损伤后继发性损伤中的相关机制。结果与结论:①基质细胞衍生因子1α(stromal-derived factor 1α,SDF-1α)/CXC趋化因子受体4(chemokine receptor 4,CXCR4)轴在神经干细胞移植治疗脊髓损伤中扮演着至关重要的角色,该信号传导机制不仅影响神经干细胞的迁移、增殖和分化,更是决定干细胞归巢至损伤部位效率的关键因素。因此,针对该轴线的调控,对于提升脊髓损伤的治疗效果具有重要意义。②针刺作为一种传统中医疗法,在脊髓损伤的继发性损伤调控中展现出独特的优势,它能够通过调节炎症反应、抑制细胞凋亡、改善微循环、减少神经胶质瘢痕形成以及对抗氧化应激等多种途径,有效减轻脊髓损伤后的继发性损伤。③针刺还能够影响SDF-1α/CXCR4轴的表达与功能,从而增强神经干细胞的归巢和存活能力,促进神经再生和功能恢复。④结合针刺与干细胞移植的疗法,是一种创新且较好的脊髓损伤治疗策略,适用于修复神经环路,它结合了传统中医的智慧与现代生物技术的优势,为脊髓损伤患者提供了新的治疗选择。然而,目前这种联合疗法仍处于研究和探索阶段,其长期疗效和安全性尚需进一步验证。⑤综合而言,针刺及神经干细胞移植治疗脊髓损伤具有巨大的临床应用潜力,但仍需深入研究和优化治疗方案。未来,期待通过更多的临床试验和机制研究,进一步揭示这一疗法的疗效机制和最佳适应证,为脊髓损伤患者带来更好的康复希望和更高效的治疗效果。

Mechanisms of secondary degeneration after partial optic nerve transection

Secondary degeneration occurs commonly in the central nervous system after traumatic injuries and following acute and chronic diseases, including glaucoma. A constellation of mechanisms have been shown to be associated with secondary degeneration including apoptosis, necrosis, autophagy, oxidative stress, excitotoxicity, derangements in ionic homeostasis and calcium influx. Glial cells, such as microglia, astrocytes and oligodendrocytes, have also been demon- strated to take part in the process of secondary injury. Partial optic nerve transection is a useful model which was established about 13 years ago. The merit of this model compared with other optic nerve injury models used for glaucoma study, including complete optic nerve transection model and optic nerve crush model, is the possibility to separate primary degeneration from secondary degeneration in location. Therefore, it provides a good tool for the study of secondary degeneration. This review will focus on the research progress of the mechanisms of secondary degeneration using partial optic nerve transection model.

Melatonin prevents oxidative stress,inflammatory activity,and DNA damage in cirrhotic rats

BACKGROUND Cirrhosis is an important health problem characterized by a significant change in liver parenchyma.In animals,this can be reproduced by an experimental model of bile duct ligation(BDL).Melatonin(MLT)is a physiological hormone synthesized from serotonin that has been studied for its beneficial properties,including its antioxidant potential.AIM To evaluate MLT’s effects on oxidative stress,the inflammatory process,and DNA damage in an experimental model of secondary biliary cirrhosis.METHODS Male Wistar rats were divided into 4 groups:Control(CO),CO+MLT,BDL,and BDL+MLT.MLT was administered(20 mg/kg)daily beginning on day 15 after biliary obstruction.On day 29 the animals were killed.Blood samples,liver tissue,and bone marrow were collected for further analysis.RESULTS BDL caused changes in biochemical and histological parameters and markers of inflammatory process.Thiobarbituric acid(0.46±0.01)reactive substance levels,superoxide dismutase activity(2.30±0.07)and nitric oxide levels(2.48±0.36)were significantly lower(P<0.001)n the groups that received MLT.DNA damage was also lower(P<0.001)in MLT-treated groups(171.6±32.9)than the BDL-only group(295.5±34.8).Tissue damage and the expression of nuclear factor kappa B,interleukin-1β,Nrf2,NQO1 and Hsp70 were significantly lower in animals treated with MLT(P<0.001).CONCLUSION When administered to rats with BDL-induced secondary biliary cirrhosis,MLT effectively restored the evaluated parameters.

Genome-wide identification of WRKY gene family and expression analysis under abiotic stresses in Andrographis paniculata

Andrographis paniculata(A.paniculata)is a Chinese herbal medicine that clears away heat,reduces inflammation,protects the liver,and promotes choleretics.The WRKYs of A.paniculata are still not well characterized,although many WRKYs have been identified in various plant species.In the present study,59 A.paniculata WRKY(ApWRKY)genes were identified and renamed on the basis of their respective chromosome distribution.These ApWRKYs were divided into three groups via phylogenetic analysis according to their WRKY domains and combined with WRKY of Arabidopsis.The 59 identified ApWRKY transcription factors were nonuniformity distributed on 23 chromosomes of A.paniculata.From the structural analysis of the conserved motifs,different ApWRKYs structures showed different biological functions,and the ApWRKY transcription factor had certain species-specificity in the evolutionary process.The expression patterns of the 41 ApWRKYs were examined through quantitative real-time PCR(qRT-PCR)in various tissues and under abiotic stresses(salt).The results showed that most of the ApWRKY had different reactions to salt treatment.In addition,the content of the four main secondary metabolites in A.paniculata leaves was determined under salt stress.The results show that under a low concentration of salt treatment,the synthesis of andrographolide can be improved.

Numerical Study of the Secondary Circulations in Rip Current Systems

To investigate the mechanism of secondary circulations in rip current systems, and to explore the relationship between wave conditions and secondary circulation intensity, a series of numerical experiments is performed using coupled nearshore wave model and circulation model. In these experiments, the rip currents and secondary circulations generated above barred beaches with rip channels are simulated. A comparison experiment is conducted to investigate the formation and hydrodynamics of the secondary circulations. Model results indicate that the secondary circulations consist of alongshore flows driven by wave set-up near the shoreline, part of the feeder currents driven by the wave set-up over the bars, and onshore flows at the end of the rip channel driven by wave breaking and convection. The existence of the secondary circulation barely affects the rip current, but narrows and intensifies the feeder currents. Three groups of experiments of varying incident wave conditions are performed to investigate the relationship between wave conditions and secondary circulation intensity. The velocity of the alongshore flow of the secondary circulation is sensitive to the variation of the incident wave height and water depth. It is also found that the alongshore flow intensity is in direct proportion to the alongshore variation of the wave height gradient between the bars and the shoreline.

Triaxial creep damage characteristics of sandstone under high crustal stress and its constitutive model for engineering application

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.

Temperature stress analysis for bi-modulus beam placed on Winkler foundation

The materials with different moduli in tension and compression are called bi-modulus materials. Graphene is such a kind of materials with the highest strength and the thinnest thickness. In this paper, the mechanical response of the bi-modulus beam subjected to the temperature effect and placed on the Winkler foundation is studied. The differential equations about the neutral axis position and undetermined parameters of the normal strain of the bi-modulus foundation beam are established. Then, the analytical expressions of the normal stress, bending moment, and displacement of the foundation beam are derived. Simultaneously, a calculation procedure based on the finite element method （FEM） is developed to obtain the temperature stress of the bi-modulus struc- tures. It is shown that the obtained bi-modulus solutions can recover the classical modulus solution, and the results obtained by the analytical expressions, the present FEM proce- dure, and the traditional FEM software are consistent, which verifies the accuracy and reliability of the present analytical model and procedure. Finally, the difference between the bi-modulus results and the classical same modulus results is discussed, and several reasonable suggestions for calculating and optimizing the certain bi-modulus member in practical engineering are presented.

Delayed treatment of secondary degeneration following acute optic nerve transection using a combination of ion channel inhibitors

Studies have shown that a combined application of several ion channel inhibitors immediately after central nervous system injury can inhibit secondary degeneration. However, for clinical use, it is necessary to determine how long after injury the combined treatment of several ion channel inhibitors can be delayed and efficacy maintained. In this study, we delivered Ca^2＋ entry-inhibiting P2X7 receptor antagonist oxidized-ATP and AMPA receptor antagonist YM872 to the optic nerve injury site via an iPRECIO-@ pump immediately, 6 hours, 24 hours and 7 days after partial optic nerve transection surgery. In addition, all of the ion channel inhibitor treated rats were administered with calcium channel antagonist lomerizine hydrochloride. It is important to note that as a result of implantation of the particular pumps required for programmable delivery of therapeutics directly to the injury site, seromas occurred in a significant proportion of animals, indicating infection around the pumps in these animals. Improvements in visual function were observed only when treatment was delayed by 6 hours; phosphorylated Tau was reduced when treatment was delayed by 24 hours or 7 days. Improvements in structure of node/paranode of Ranvier and reductions in oxidative stress indicators were also only observed when treatment was delayed for 6 hours, 24 hours, or 7 days. Benefits of ion channel inhibitors were only observed with time-delayed treatment, suggesting that delayed therapy of Ca^2＋ ion channel inhibitors produces better neuroprotective effects on secondary degeneration, at least in the presence of seromas.

江苏省高年资护士共情疲劳的潜在类别分析

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。