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Criticality,resilience and prioritization of components in interdependent infrastructure systems:An overview of definitions and quantitative modelling approaches
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作者 Georgios Alexandros Chatzistefanou Albert S.Chen +2 位作者 Slobodan Djordjevic Lydia S.Vamvakeridou-Lyroudia Dragan A.Savic 《Resilient Cities and Structures》 2026年第1期118-132,共15页
Enhancing the resilience of critical infrastructure(CI)systems has become a focal point of national and inter-national policies.However,the formulation of resilience enhancement strategies often requires component-(i.... Enhancing the resilience of critical infrastructure(CI)systems has become a focal point of national and inter-national policies.However,the formulation of resilience enhancement strategies often requires component-(i.e.asset-)level prioritization,which entails many complexities.Acknowledging the complex and interdependent nature of infrastructure systems,this paper aims to aid researchers,practitioners and policy-makers by pre-senting a review of the relative literature and current state-of-the-art,and by identifying future research op-portunities to improve the applicability and operationalizability of CI component identification and prioritization methods.Theoretical and practical applications are reviewed for definitions,analysis and modelling approaches regarding the resilience of interdependent infrastructure systems.A detailed review of infrastructure criticality definitions,component criticality assessment and prioritization frameworks,from scientific,policy and other documents,is presented.A discussion on social justice and equity dimensions therein is included,which have the potential to greatly influence decisions and should always be incorporated in infrastructure planning and in-vestment discussions.The findings of this review are discussed in terms of applicability and operationalizability.Key recommendations for future research include:(i)developing quantification frameworks for CI component criticality based on formal definitions and multiple criteria,(ii)incorporating the entire resilience cycle of CI in component prioritization,(iii)accounting for the socio-technical nature of CI systems by integrating social di-mensions and their wider operating environment and(iv)developing comprehensive model validation,cali-bration and uncertainty analysis frameworks. 展开更多
关键词 Critical infrastructure Interdependencies CRITICALITY RESILIENCE component importance measures Cascading effects System-of-systems
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Antithrombotic effects of the effective components group of Xiaoshuantongluo formula in vivo and in vitro 被引量:8
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作者 ZHAO Yan CHU Xiao +2 位作者 PANG Xiao-Bin WANG Shao-Hua DU Guan-Hua 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2015年第2期99-107,共9页
The present study was designed to investigate the antithrombotic effects and underlying mechanisms of the effective components group(ECG) of Xiaoshuantongluo recipe(XECG) and to further verify the rationality and feas... The present study was designed to investigate the antithrombotic effects and underlying mechanisms of the effective components group(ECG) of Xiaoshuantongluo recipe(XECG) and to further verify the rationality and feasibility of ECG-guided methodology in traditional Chinese medicine(TCM) research. The arterial thrombosis model induced by ferric chloride(FeC l3) oxidation and the venous thrombosis model induced by inferior vena cava ligation were established to evaluate the antithrombotic potential of XECG. Our results indicated that XECG significantly prolonged the time to occlusion, activated partial thromboplastin time(APTT), and prothrombin time(PT), and markedly inhibited adenosine diphosphate(ADP)-induced platelet aggregation in the 20% Fe Cl3-induced arterial thrombosis model. The superoxide dismutase(SOD) activity was significantly increased and the levels of malondialdehyde(MDA) and nitric oxide(NO) were dramatically decreased in the plasma of arterial thrombosis rats after XECG treatment for 12 days. Furthermore, XECG markedly reduced the weight of thrombus formed by inferior vena cava ligation. Additionally, XECG exhibited 2,2-diphenyl-1-picrylhydrazyl(DPPH) free radical scavenging activity and protective effect on mitochondrial lipid peroxidation. In summary, XECG played an important role in the prevention of thrombosis through interacting with multiple targets, including inhibition of platelet aggregation and coagulation and repression of oxidative stress. The ECG-guided methodology was validated as a feasible tool in TCM research. 展开更多
关键词 Traditional Chinese medicine effective components group THROMBOSIS Platelet aggregation Oxidative stress Radical scavenging
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A combination of four effective components derived from Sheng-mai san attenuates hydrogen peroxide-induced injury in PC12 cells through inhibiting Akt and MAPK signaling pathways 被引量:4
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作者 CAO Guo-Sheng LI Shao-Xia +4 位作者 WANG Yan XU Ying-Qiong LV Yan-Ni KOU Jun-Ping YU Bo-Yang 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第7期508-517,共10页
The present study was designed to investigate whether a combination of four effective components derived from Sheng-mai san(SMXZF; ginsenoside Rb1: ginsenoside Rg1: DT^(–1)3: Schizandrol A as 6 : 9 : 4 : 5) could att... The present study was designed to investigate whether a combination of four effective components derived from Sheng-mai san(SMXZF; ginsenoside Rb1: ginsenoside Rg1: DT^(–1)3: Schizandrol A as 6 : 9 : 4 : 5) could attenuate hydrogen peroxide(H_2O_2)-induced injury in PC12 cells, focusing on the Akt and MAPK pathways. The PC12 cells were exposed to H_2O_2(400 mmol·L^(–1)) for 1 h in the presence or absence of SMXZF pre-treatment for 24 h. Cell viability was measured by MTT assay. The efflux of lactate dehydrogenase(LDH), the intracellular content of malondialdehyde(MDA), the activities of superoxide dismutase(SOD), and caspase-3 were also determined. Cell apoptosis was measured by Hoechst 33342 staining and Annexin V-FITC/PI staining method. The expression of Bcl-2, Bax, cleaved caspase-3, Akt, and MAPKs were detected by Western blotting analyses. SMXZF pretreatment significantly increased the cell viability and SOD activity and improved the cell morphological changes, while reduced the levels of LDH and MDA at the concentrations of 0.1, 1 and 10 μg·m L^(–1). SMXZF also inhibited H_2O_2-induced apoptosis in PC12 cells. Moreover, SMXZF reduced the activity of caspase-3, up-regulated the protein ratio of Bcl-2 and Bax and inhibited the expression of cleaved caspase-3, p-Akt, p-p38, p-JNK and p-ERK1/2 in H_2O_2-induced PC12 cells. Co-incubation of Akt inhibitor or p38 inhibitor partly attenuated the protection of SMXZF against H_2O_2-injured PC12 cells. In conclusion, our findings suggested that SMXZF attenuated H_2O_2-induced injury in PC12 cells by inhibiting Akt and MAPKs signaling pathways, which might shed insights on its neuroprotective mechanism. 展开更多
关键词 COMBINATION of effective TCM components Sheng-mai SAN SMXZF PC12 cells Hydrogen peroxide AKT MAPKs
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Screening the effective components in treating dampness stagnancy due to spleen deficiency syndrome and elucidating the potential mechanism of Poria water extract 被引量:3
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作者 LI Huijun ZHANG Dandan +9 位作者 WANG Tianhe LUO Xinyao XIA Heyuan PAN Xiang HAN Sijie YOU Pengtao WEI Qiong LIU Dan ZOU Zhongmei YE Xiaochuan 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2023年第2期83-98,共16页
Poria is an important medicine for inducing diuresis to drain dampness from the middle energizer.However,the specific effective components and the potential mechanism of Poria remain largely unknown.To identify the ef... Poria is an important medicine for inducing diuresis to drain dampness from the middle energizer.However,the specific effective components and the potential mechanism of Poria remain largely unknown.To identify the effective components and the mechanism of Poria water extract(PWE)to treat dampness stagnancy due to spleen deficiency syndrome(DSSD),a rat model of DSSD was established through weight-loaded forced swimming,intragastric ice-water stimulation,humid living environment,and alternate-day fasting for 21 days.After 14 days of treatment with PWE,the results indicated that PWE increased fecal moisture percentage,urine output,D-xylose level and weight;amylase,albumin,and total protein levels;and the swimming time of rats with DSSD to different extents.Eleven highly related components were screened out using the spectrum-effect relationship and LC-MS.Mechanistic studies revealed that PWE significantly increased the expression of serum motilin(MTL),gastrin(GAS),ADCY5/6,p-PKAα/β/γcat,and phosphorylated cAMP-response element binding protein in the stomach,and AQP3 expression in the colon.Moreover,it decreased the levels of serum ADH,the expression of AQP3 and AQP4 in the stomach,AQP1 and AQP3 in the duodenum,and AQP4 in the colon.PWE induced diuresis to drain dampness in rats with DSSD.Eleven main effective components were identified in PWE.They exerted therapeutic effect by regulating the AC-cAMP-AQP signaling pathway in the stomach,MTL and GAS levels in the serum,AQP1 and AQP3 expression in the duodenum,and AQP3 and AQP4 expression in the colon. 展开更多
关键词 Poria water extract Dampness stagnancy due to spleen deficiency syndrome Spectrum-effect relationship effective components MECHANISMS
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Technology for Extracting Effective Components from Fish Scale 被引量:1
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《Journal of Food Science and Engineering》 2017年第7期351-358,共8页
The research of the category and extraction methods of effective ingredients of fish scale was reviewed at home and abroad. The extraction process of fish scale was studied, including collagen, hydroxyapatite, lecithi... The research of the category and extraction methods of effective ingredients of fish scale was reviewed at home and abroad. The extraction process of fish scale was studied, including collagen, hydroxyapatite, lecithin, guanine etc. The different extraction methods and the components were analyzed. The research of effective ingredients of fish scales was reviewed as theory basis to further research and comprehensive development. 展开更多
关键词 Fish scale effective components COLLAGEN HYDROXYAPATITE LECITHIN guanine.
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EMPIRICAL BAYES TEST PROBLEMS OF VARIANCE COMPONENTS IN RANDOM EFFECTS MODEL 被引量:3
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作者 韦来生 张伟平 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期274-282,共9页
Bayes decision rule of variance components for one-way random effects model is derived and empirical Bayes (EB) decision rules are constructed by kernel estimation method. Under suitable conditions, it is shown that t... Bayes decision rule of variance components for one-way random effects model is derived and empirical Bayes (EB) decision rules are constructed by kernel estimation method. Under suitable conditions, it is shown that the proposed EB decision rules are asymptotically optimal with convergence rates near O(n-1/2). Finally, an example concerning the main result is given. 展开更多
关键词 Empirical Bayes test variance components random effects model convergence rates
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Review of Effects of Active Components of Gastrodiae Rhizoma on Central Nervous System 被引量:1
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作者 Hua ZHU Piaoling HUANG +3 位作者 Wenqi YANG Anda WEI Ruiting HE Zhonghua DAI 《Medicinal Plant》 CAS 2019年第6期39-41,共3页
In order to explore the pharmacological effects of active components of Gastrodiae Rhizoma on the central nervous system,through consulting related literatures,this paper summarized the pharmacological effects of the ... In order to explore the pharmacological effects of active components of Gastrodiae Rhizoma on the central nervous system,through consulting related literatures,this paper summarized the pharmacological effects of the active components of Gastrodiae Rhizoma.The pharmacological effects of the active components of Gastrodiae Rhizoma on the central nervous system include improving the ability of learning and memory,analgesia,sedation and hypnosis,anticonvulsant,anti-aging,anti-anxiety and neuroprotective effects.The active components of Gastrodiae Rhizoma have certain curative effect in the treatment of some diseases of the central nervous system.At present,it has been widely used clinically.There are no toxic and side effects at conventional doses,and it is worth popularizing and applying. 展开更多
关键词 Gastrodiae Rhizoma ACTIVE components CENTRAL nervous system PHARMACOLOGICAL effectS
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Research Progress on Functional Components and Pharmacological Effects of Red Jujube ( Ziziphus jujuba Mill.)
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作者 Qian SHI 《Agricultural Biotechnology》 CAS 2023年第4期71-74,87,共5页
Red jujube(Ziziphus jujuba Mill.),as a traditional Chinese medicine and edible plant,has a long history and extensive uses.Red jujubes are not only widely used in the food industry and traditional Chinese medicine pre... Red jujube(Ziziphus jujuba Mill.),as a traditional Chinese medicine and edible plant,has a long history and extensive uses.Red jujubes are not only widely used in the food industry and traditional Chinese medicine preparations,but also have attracted widespread research interest due to their rich functional components and various pharmacological effects.This paper reviewed the main functional components of jujubes,including polysaccharides,triterpenoid saponins,organic acids and alkaloids,and discussed in detail the pharmacological effects of these components such as blood sugar-regulating,antioxidant,anti-inflammatory and anti-tumor effects.Furthermore,the paper also summarized the safety issues such as drug interactions and toxic side effects of jujubes,and prospected the future development direction of jujube research. 展开更多
关键词 JUJUBE Functional components Pharmacological effects
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Advances in Research of Chemical Components and Pharmacological Effects of Platycladus orientalis Leaves
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作者 Ruifeng ZHANG Yang ZENG +4 位作者 Likuan LIU Hongyu WANG Wenming ZUO Junyan ZHANG Jinping LI 《Medicinal Plant》 CAS 2021年第4期8-12,共5页
Platycladi Cacumen(Platycladus orientalis leaf)is a traditional Chinese medicine with a variety of medicinal values,and its efficacy has been recorded by many ancient books.Its chemical components mainly include flavo... Platycladi Cacumen(Platycladus orientalis leaf)is a traditional Chinese medicine with a variety of medicinal values,and its efficacy has been recorded by many ancient books.Its chemical components mainly include flavonoids,volatile oil,tannins and so on.Pharmacological studies have confirmed that P.orientalis leaves have various pharmacological effects such as antibacterial,anti-oxidant,anti-tumor,hair growth promoting and hemostatic effects.Through review of the research on the chemical components and pharmacological effects of P.orientalis leaves,this study is intended to provide reference for the research,development and utilization of P.orientalis. 展开更多
关键词 Platycladus orientalis Platycladi Cacumen Chemical components Pharmacological effects
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Effect of Loading Paths on Hydroforming Tubular Square Components
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作者 Hongyang LI Shijian YUAN +3 位作者 Kun DAI Lihui LANG Xiaosong WANG Zhubin HE and Zhongren WANG School of Materials Science and Engineering, Harbin institute of Technology, Harbin 150001, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第1期158-,共1页
The influence of loading path on tube hydroforming process is discussed in this paper with finiteelement simulation. Four different loading paths are utilized in simulating the forming process of square tubular compo... The influence of loading path on tube hydroforming process is discussed in this paper with finiteelement simulation. Four different loading paths are utilized in simulating the forming process of square tubular component with hydroforming and the result of different loading path is presented. Among the result. the thickness distribution of bilinear loading path is the most uniform one. It shows that the increase of punch displacement in the stage of high pressure is beneficial to the forming of component for optimized Stress condition. 展开更多
关键词 effect of Loading Paths on Hydroforming Tubular Square components
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Comparison of REML and MINQUE for Estimated Variance Components and Predicted Random Effects
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作者 Nan Nan Johnie N. Jenkins +1 位作者 Jack C. McCarty Jixiang Wu 《Open Journal of Statistics》 2016年第5期814-823,共11页
Linear mixed model (LMM) approaches have been widely applied in many areas of research data analysis because they offer great flexibility for different data structures and linear model systems. In this study, emphasis... Linear mixed model (LMM) approaches have been widely applied in many areas of research data analysis because they offer great flexibility for different data structures and linear model systems. In this study, emphasis is placed on comparing the properties of two LMM approaches: restricted maximum likelihood (REML) and minimum norm quadratic unbiased estimation (MINQUE) with and without resampling techniques being included. Bias, testing power, Type I error, and computing time were compared between REML and MINQUE approaches with and without Jackknife technique based on 500 simulated data sets. Results showed that MINQUE and REML methods performed equally regarding bias, Type I error, and power. Jackknife-based MINQUE and REML greatly improved power compared to non-Jackknife based linear mixed model approaches. Results also showed that MINQUE is more time-saving compared to REML, especially with the use of resampling techniques and large data set analysis. Results from the actual cotton data analysis were in agreement with our simulated results. Therefore, Jackknife-based MINQUE approaches could be recommended to achieve desirable power with reduced time for a large data analysis and model simulations. 展开更多
关键词 Comparison of REML and MINQUE for Estimated Variance components and Predicted Random effects
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Antifungal Effect of Streptomyces 702 Antifungal Monomer Component DZP8 on Rhizoctonia solani and Magnaporthe grisea 被引量:1
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作者 芦慧 涂晓嵘 +2 位作者 徐佳 冯华根 涂国全 《Agricultural Science & Technology》 CAS 2012年第11期2370-2374,2378,共6页
The aim of this study was to investigate the in vitro antifungal effects of antifungal monomer component DZP8 isolated from Streptomyces 702 on the mycelium growth, sclerotium formation and germination of Rhizoctonia ... The aim of this study was to investigate the in vitro antifungal effects of antifungal monomer component DZP8 isolated from Streptomyces 702 on the mycelium growth, sclerotium formation and germination of Rhizoctonia solani and on the mycelium growth, conidial formation, germination, appressorium formation of Magnaporthe grisea. The results showed that the antifungal monomer component DZP8 has strong antifungal effect on both the R. solani and M. grisea. The EC50 and EC90 of DZP8 were 1.81 and 3.35 μg/ml on Ft. solani respectively, and 37.01 and 136.21 μg/ml on M. grisea respectively. Under the treatment of 48.01 μg/ml DZP8, the sclerotium formation rate of R. solani was just 39.21%, the formation time delayed by 216 h and the dry weight decreased by 81.37% in comparison the con- trol; and 33.51 μg/ml DZP8 significantly inhibited the sclerotium germination. In the presence of 160.08 μg/ml DZP8, the sporulation of M. grisea was just 9.29% of control sample; 20.14 μg/ml DZP8 inhibited the conidial germination suppression rate by 95.16%, and the appressorium formation by 100%. 展开更多
关键词 Streptomyces 702 Monomer component DZP8 Rhizoctonia solani Mag-naporthe grisea Antifungal effect
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Ion adsorption components in liquid/solid systems 被引量:21
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作者 WU Xiao-fu HU Yue-li ZHAO Fang HUANG Zhong-zi LEI Dian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1167-1175,共9页
Experiments on Zn^2+ and Cd^2+ adsorptions on vermiculite in aqueous solutions were conducted to investigate the widely observed adsorbent concentration effect on the traditionally defined adsorption isotherm in the... Experiments on Zn^2+ and Cd^2+ adsorptions on vermiculite in aqueous solutions were conducted to investigate the widely observed adsorbent concentration effect on the traditionally defined adsorption isotherm in the adsorbate range 25--500 mg/L and adsorbent range 10--150 g/L. The results showed that the equilibrium ion adsorption density did not correspond to a unique equilibrium ion concentration in liquid phase. Three adsorbate/adsorbent ratios, the equilibrium adsorption density, the ratio of equilibrium adsorbate concentration in liquid phase to adsorbent concentration, and the ratio of initial adsorbate concentration to adsorbent concentration, were found to be related with unique values in the tested range. Based on the assumption that the equilibrium state of a liquid/solid adsorption system is determined by four mutually related components: adsorbate in liquid phase, adsorbate in solid phase, uncovered adsorption site and covered adsorption site, and that the equilibrium chemical potentials of these components should be equalized, a new model was presented for describing ion adsorption isotherm in liquid/solid systems. The proposed model fit well the experimental data obtained from the examined samples. 展开更多
关键词 adsorbent effect adsorbate/adsorbent ratio adsorption component chemical potential Zn^2+ Cd^2+ VERMICULITE
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Natural products and food components with anti-Helicobacter pylori activities 被引量:4
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作者 Hiroaki Takeuchi Vu Thu Trang +3 位作者 Norihito Morimoto Yoshie Nishida Yoshihisa Matsumura Tetsuro Sugiura 《World Journal of Gastroenterology》 SCIE CAS 2014年第27期8971-8978,共8页
The bacterial pathogen Helicobacter pylori (H. pylori) colonizes in over half of the world&#x02019;s population. H. pylori that establishes life-long infection in the stomach is definitely associated with gastro-d... The bacterial pathogen Helicobacter pylori (H. pylori) colonizes in over half of the world&#x02019;s population. H. pylori that establishes life-long infection in the stomach is definitely associated with gastro-duodenal diseases and a wide variety of non-gastrointestinal tract conditions such as immune thrombocytopenia. Triple therapy which consists of a proton pump inhibitor and combinations of two antibiotics (amoxicillin, clarithromycin or amoxicillin, metronidazol) is commonly used for H. pylori eradication. Recently, the occurrence of drug-resistant H. pylori and the adverse effect of antibiotics have severely weakened eradication therapy. Generally antibiotics induce the disturbance of human gastrointestinal microflora. Furthermore, there are inappropriate cases of triple therapy such as allergy to antibiotics, severe complications (liver and/or kidney dysfunction), the aged and people who reject the triple therapy. These prompt us to seek alterative agents instead of antibiotics and to develop more effective and safe therapy with these agents. The combination of these agents actually may result in lower a dose of antibiotics. There are many reports world-wide that non-antibiotic substances from natural products potentially have an anti-H. pylori agent. We briefly review the constituents derived from nature that fight against H. pylori in the literature with our studies. 展开更多
关键词 Anti-Helicobacter pylori effect Natural product Food component In vitro and in vivo effects Human health Helicobacter pylori treatment Combined effect
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The Influence of Some Key Parameters on Fatigue Life of Common Metallic Components 被引量:1
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作者 LIU Yi lun (College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 2000年第3期159-161,共3页
The effect of key parameters on fatigue life of common metallic components, e.g. steel, aluminium alloy, has been analysed quantitatively. The influential coverage and degree of these parameters have been investigated... The effect of key parameters on fatigue life of common metallic components, e.g. steel, aluminium alloy, has been analysed quantitatively. The influential coverage and degree of these parameters have been investigated systematically, some phenomena which can′t be discovered with qualitative analysis method have been revealed, a series of valuable conclusions has been obtained, which would be very beneficial to fatigue resistant design and improvement of anti fatigue ability of metallic components. 展开更多
关键词 METALLIC material component FATIGUE LIFE KEY PARAMETER effect
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Effects of acrous gramimeus and its main component alpha-asarone on the reactivity and convulsive threshold of immature rats to electric stimulation 被引量:3
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作者 Libin Yang Shulei Li +1 位作者 Yuhong Wang Yanzhi Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第1期78-80,共3页
BACKGROUND: The traditional Chinese medicine acrous gramimeus is the dry rhizome of Acrous gramimeus Soland, a kind of Araceae familial perennial herb, which has a sedation action, anticonvulsant and antiepileptic ef... BACKGROUND: The traditional Chinese medicine acrous gramimeus is the dry rhizome of Acrous gramimeus Soland, a kind of Araceae familial perennial herb, which has a sedation action, anticonvulsant and antiepileptic effect. Its effective component has not been known yet, and α-asarone, the major component of the volatile oil extracted from acrous gramineus, has been supposed to play a necessary role in it. OBJECTIVE: To explore the effects of acrous gramimeu and α-asarone on the reactivity and convulsive threshold to electric stimulation in immature rats, furthermore, attempt to definitize the anticonvulsant effect of α-asarone. DESIGN: A randomized controlled study.SETTINGS: Department of Pediatrics, First Hospital of Jilin University; Department of Histology and Embryology, School of Basic Medical Sciences of Jilin University; Department of Neurology, First Clinical Hospital affiliated to Harbin Medical University; Department of Internal Medicine, Children's Hospital of Changchun City. MATERIALS : Seventy 3-week immature Wistar rats (either males or females) of 34-40 g were used. Acrous gramimeu (1 g/bag, the content of α-oasarone was 0.046 26%-0.070 16%) with the batch number of 0307113 was provided by Tianjiang Medicine Company Limited, Jiangyin City. α-asarone tablet (60 mg per tablet) with the batch number of 030219 was provided by Tianwei Pharmaceutical Factory, Shenyang City. α-asarone injectable preparation (2 mL per piece) with the batch number of 030105 was provided by Shuanghe Medicine Limited Company, Beijing City. METHODS : The experiments were carried out in the Neurological Laboratory of the First Hospital of Jilin University between August and October in 2004.① The 70 rats were randomly divided into intragastric subset and intraperitoneal subset. The intragastric subset included four groups of control, phenobarbital sodium, acrous gramimeu and α-asarone; the intraperitoneal subset included three groups of control, phenobarbital sodium and α-asarone. There were 10 rats per group. ② In the intragastric subset, different group was treated with saline (1 mL for each time, phenobarbital sodium (18 mg/kg per day), acrous gramineu (2 350 mg/kg per day) and α-asarone (29 mg/kg per day) respectively twice every day for 5 days. In the intraperitoneal subset, different group was treated with saline (0.5 mL), phenobarbital sodium (29 mg/kg) and α-asarone (2.9 mg/kg) respectively. ③ Before and after administration for 5 days in the intragastric subset as well as before and after administration for about 1 hour in the intraperitoneal subset respectively, the rats were given electric stimulation with the NIHOM KOMDEM multifunctional electrophysiological recorder, and the reactivity and convulsive threshold to electric stimulation of the rats were recorded. MAIN OUTCOME MEASURES: The reactivity and convulsive threshold to electric stimulation in immature rats were compared. RESULTS: All the rats were involved in the analysis of results. ① Results for intragastric administration: Before intragastric administration, there were no obvious differences in the reactivity and convulsive threshold to electric stimulation among the groups (P 〉 0.05). After intragastric administration for 5 days, the reactivity and convulsive threshold to the electric stimulation had no obvious changes in the control group, but those were significantly higher than before administration in the drug administration groups (t=-3.317-7.401, P 〈 0.01), which were also obviously higher than those in the control group (t=3.027-8.941, P 〈 0.01), and those in the acrous gramimeu group and α-asarone group were not markedly different from those in the phenobarbital sodium group. ② Results for intraperitoneal injection: Before intraperitoneal injection, the reactivity and convulsive threshold to the electric stimulation had no obvious differences among the groups. After the intraperitoneal injection for 1 hour, the reactivity and convulsive threshold to the electric stimulation had no obvious change in the control group, but those were significantly higher than before administration in the drug administration groups (P 〈 0.01), which were also obviously higher than those in the control group (t=6.211-7.237, P 〈 0.01; t=4.085-5.633, P 〈 0.05), and there was no marked difference between α-asarone group and phenobarbital sodium group (P 〉 0.05).CONCLUSION : ① As effective anticonvulsants, both acrous gramineu and α-asarone can enhance the reactivity and convulsive threshold of immature rats to electric stimulation. ② As one of the major effective components against convulsion of acrous gramineu, α-asarone is equivalent to phenobarbital sodium. 展开更多
关键词 effects of acrous gramimeus and its main component alpha-asarone on the reactivity and convulsive threshold of immature rats to electric stimulation THAN
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Effect of chemical component on shape memory effect of Fe-Mn-Si-Ni-C-RE shape memory alloy
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作者 SI Naichao, JIA Zhihong, and QI Longbiao 《Rare Metals》 SCIE EI CAS CSCD 2004年第1期87-87,共1页
Effect of chemical component on shape memory effect (SME) of Fe-Mn-Si-Ni-C-RE shape memory alloys was studied by bent measurement, thermal cycle training, SEM etc. Results of study indicate that the alloys with high M... Effect of chemical component on shape memory effect (SME) of Fe-Mn-Si-Ni-C-RE shape memory alloys was studied by bent measurement, thermal cycle training, SEM etc. Results of study indicate that the alloys with high Mn content (25%) appeare better SME, especially in lower strain. SME improves evidently when Si is higher content, especially it’s range from 3% up to 4%. But brittleness of Fe-Mn-Si-Ni-C-RE alloy increases by increasing the Si content. SME of the alloy is weakening gradually as carbon content increases under small strain (3%). But in the condition of large strain (above 6%), SME of the alloy whose carbon content ranges from 0.1 % to 0.12% shows small decreasing range, especially of alloy with the addition of compound RE. 展开更多
关键词 chemical component Fe-Mn-Si-Ni-C-RE shape memory alloy shape memory effect STRAIN
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Effect of chemical component on shape memory effect of Fe-Mn-Si-Ni-C-RE shape memory alloy
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作者 NaichaoSi ZhihongJia LongbiaoQi 《Journal of University of Science and Technology Beijing》 CSCD 2004年第1期75-80,共6页
Effect of chemical component on shape memory effect (SME) of Fe-Mn-Si-Ni-C-REshape memory alloys was studied by bent measurement, thermal cycle training, SEM etc. Results ofstudy indicate that the alloys with high Mn ... Effect of chemical component on shape memory effect (SME) of Fe-Mn-Si-Ni-C-REshape memory alloys was studied by bent measurement, thermal cycle training, SEM etc. Results ofstudy indicate that the alloys with high Mn content (25%) appeare better SME, especially in lowerstrain. SME improves evidently when Si is higher content, especially it's range from 3% up to 4%.But brittleness of Fe-Mn-Si-Ni-C-RE alloy increases by increasing the Si content. SME of the alloyis weakening gradually as carbon content increases under small strain (3%). But in the condition oflarge strain (above 6%), SME of the alloy whose carbon content ranges from 0.1 % to 0.12% showssmall decreasing range, especially of alloy with the addition of compound RE. 展开更多
关键词 chemical component Fe-Mn-Si-Ni-C-RE shape memory alloy shape memory effect STRAIN
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Impact of sampling interval on variance components of epoch-wise residual error in relative GPS positioning: A case study of a 40-km-long baseline
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作者 Darko Andic 《Geodesy and Geodynamics》 CSCD 2021年第5期368-380,共13页
The study presents sampling interval impacts on variance components of the epoch-wise residual errors in relative GPS positioning. In the variance components estimation process, the 2-way nested ANOVA method was used.... The study presents sampling interval impacts on variance components of the epoch-wise residual errors in relative GPS positioning. In the variance components estimation process, the 2-way nested ANOVA method was used. For that purpose, GPS observation data during four months at two permanent GPS stations, establishing a 40-km-long baseline as a part of the Montenegrin permanent network(Monte Pos), were used. The study results showed that there is no statistically significant impact of sampling interval changes on epoch-wise variance components related to the residual tropospheric and ionospheric delays(effect a) when it comes to such a baseline. However, it is not the case with epoch-wise variance components related to the interstation-distance-independent residual ‘far-field’ multipath effect(effect b). It turned out that the absolute values of relative differences of standard deviations of the effect a on the relative GPS coordinates(e, n and u) had maximum values 11.1%, 10.2% and 8.9%,respectively. Keeping the same order of presentation for the effect b, the values of 5.9%, 9.9% and 12.5%were obtained. In addition, absolute values of relative differences of standard deviations of horizontal and vertical position had maximum values of 3.8% and 7.7%, respectively. 展开更多
关键词 Relative GPS positioning Residual effects Variance components Positional accuracy Sampling interval
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Enhanced quasi-three-dimensional transient simulation technique incorporating component volume effects for aero engine
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作者 Yuchen DAI Manxiang SONG +1 位作者 Donghai JIN Xingmin GUI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第12期325-346,共22页
Current transient analysis predominantly relies on zero-dimensional/one-dimensional tools,proficient at capturing aerothermodynamic variations across critical engine stations but insufficient for analyzing the interna... Current transient analysis predominantly relies on zero-dimensional/one-dimensional tools,proficient at capturing aerothermodynamic variations across critical engine stations but insufficient for analyzing the internal flow field evolution during transients.Addressing this gap,the study presents an enhanced quasi-three dimensional(quasi-3D)transient simulation technique that integrates component volume effects,offering a significant leap from the preceding quasi-3D transient simulation method based on quasi-steady assumption.By embedding the component volume effects on density,momentum,and energy within the physical temporal dimension of the Navier-Stokes equations,the refined quasi-3D transient model achieves a closer representation of physical phenomena.Validation against a single-shaft turbofan engine’s experimental data confirms the model’s accuracy.Average errors for key performance indicators,including shaft speed,thrust,mass flow rate,and critical component exit temperature and pressure,remain below 0.41%,5.69%,2.55%,3.18%and 0.67%,respectively.Crucially,the model exposes a discernible temporal lag in the compressor outlet pressure and temperature response due to volume effects—previously unquantified in quasi-3D transient simulations.And further exploration of the meridional flow field emphasizes the consequential role of volumes in transient flow field evolution.Incorporating volume effects within quasi-3D transient simulations enhances engine modeling and is pivotal for precise transient analysis in engine design and optimization. 展开更多
关键词 Engines Transient simulation Quasi-3D modeling component volume effects Flow field evolution Transient performance analysis
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