Objective: To research the effectiveness of ulinastatin in combination with continuous renal replacement therapy in treating sepsis acute kidney injury and its effect on systemic inflammation, immune function and miRA...Objective: To research the effectiveness of ulinastatin in combination with continuous renal replacement therapy in treating sepsis acute kidney injury and its effect on systemic inflammation, immune function and miRAN expression. Methods: The 84 patients who were diagnosed with sepsis complicated by acute kidney injury in our hospital between May 2020 and June 2022 were chosen and randomly assigned to the study group (n = 42) and the control group (n = 42). Ulinastatin in combination with continuous renal replacement therapy was administered to the study group, whereas the control group was administered with continuous renal replacement therapy alone. Both groups’ clinical effects were observed. The levels of blood urea nitrogen (BUN), serum creatinine (SCr), tumor necrosis factor-α (TNF-α), high sensitivity Creactive protein (hs-CRP), vascular cell adhesion molecule-1 (VCAM-1), IgG, IgA, IgM, expression levels of miR-233 and miR-10a were compared among both the groups, pre-, and post-treatment. Results: The study group’s overall effectiveness rate was higher that is 95.24%, in comparison to the control group’s 78.57%, and this difference was statistically significant (P α, hs-CRP, VCAM-1, and miR-233 and miR-10a expression levels in both the study and control groups were decreased, however, the study group had reduced levels in comparison to the control group, with statistically significant differences (P P Conclusion: Ulinastatin in combination with continuous renal replacement therapy for treating sepsis acute kidney injury exhibits a positive effect and can significantly improve the systemic inflammation and immune function in patients.展开更多
Severe haze pollution that occurred in January 2014 in Wuhan was investigated. The factors leading to Wuhan’s PM2.5 pollution and the characteristics and formation mechanism were found to be significantly different f...Severe haze pollution that occurred in January 2014 in Wuhan was investigated. The factors leading to Wuhan’s PM2.5 pollution and the characteristics and formation mechanism were found to be significantly different from other megacities, like Beijing. Both the growth rates and decline rates of PM2.5 concentrations in Wuhan were lower than those in Beijing, but the monthly PM2.5 value was approximately twice that in Beijing. Furthermore, the sharp increases of PM2.5 concentrations were often accompanied by strong winds. A high-precision modeling system with an online source-tagged method was established to explore the formation mechanism of five haze episodes. The long-range transport of the polluted air masses from the North China Plain (NCP) was the main factor leading to the sharp increases of PM2.5 concentrations in Wuhan, which contributed 53.4% of the monthly PM2.5 concentrations and 38.5% of polluted days. Furthermore, the change in meteorological conditions such as weakened winds and stable weather conditions led to the accumulation of air pollutants in Wuhan after the long-range transport. The contribution from Wuhan and surrounding cities to the PM2.5 concentrations was determined to be 67.4% during this period. Under the complex regional transport of pollutants from surrounding cities, the NCP, East China, and South China, the five episodes resulted in 30 haze days in Wuhan. The findings reveal important roles played by transregional and intercity transport in haze formation in Wuhan.展开更多
To evaluate the relationships among clones and open pollinated families from the same plus trees and to select elite breeding materials,growth,and wood characteristics of 33-year-old Pinus korainsis clones and familie...To evaluate the relationships among clones and open pollinated families from the same plus trees and to select elite breeding materials,growth,and wood characteristics of 33-year-old Pinus korainsis clones and families were measured and analyzed.The results show that growth and wood characters varied significantly.The variation due to clonal effects was higher than that of family effects.The ratio of genetic to phenotypic coefficient of variation of clones in growth and wood traits was above 90%,and the repeatability of these characteristics was more than 0.8,whereas the ratio of genetic to phenotypic coefficient of variation of families was above 90%.The broad-sense heritability of all characteristics exceeded 0.4,and the narrow-sense family heritability of growth traits was less than 0.3.Growth characteristics were positively correlated with each other,but most wood properties were weakly correlated in both clones and families.Fiber length and width were positively correlated between clones and families.Using the membership function method,eleven clones and four families were selected as superior material for improved diameter growth and wood production,and two families from clonal and open-pollinated trees showed consistently better performance.Generally,selection of the best clones is an effective alternative to deployment of families as the repeatability estimates from clonal trees were higher than narrow-sense heritability estimates from open pollinated families.The results provide valuable insight for improving P.koraiensis breeding programs and subsequent genetic improvement.展开更多
Background: Developing a novel, efficient biomarker for detecting malignant tumors is essential for the early diagnosis of cancers. Our aim was to assess the diagnostic value of a potential plasma tumor marker, thiore...Background: Developing a novel, efficient biomarker for detecting malignant tumors is essential for the early diagnosis of cancers. Our aim was to assess the diagnostic value of a potential plasma tumor marker, thioredoxin reductase (TR), which is expressed in many types of malignant tumor, for the non-invasive detection of cancers. Methods: The plasma activities of TR were measured in 1513 patients with common clinical diseases, 59 patients with benign tumors, and 154 patients with cancers and 586 healthy controls. The area under the ROC curve (AUC) of TR and logistic regression results of different groups were compared by sensitivity, specificity and Youden’s index. Diagnostic cut-offs and clinical reference intervals were established via ROC curve analysis. Results: The logistic regression indicated that TR activity can discriminate between cancers and benign tumors or other common diseases very well (p < 0.0001), with an area under the curve from the receiver-operator characteristics between 0.91 and 0.96. The positive critical value was 2.51 and the cancer critical value was 9.90. The diagnostic gray zone (2.51 - 9.90) may be associated with benign tumors and some common clinical diseases. Conclusions: As a novel potential marker of malignant tumors with quantitative evaluation of proliferation, TR activity detection has an excellent diagnostic potential for early-stage malignant tumors. Impact: The convenient, economical, relatively non-invasive, and reproducible detection method of TR activity makes it suitable for routine clinical practice.展开更多
Off-line programming provides an essential link between CAD and CAM, whose development should result in greater use of robotic arc welding. An arc welding system with a robot and a rotating/tilting positioner is a ma...Off-line programming provides an essential link between CAD and CAM, whose development should result in greater use of robotic arc welding. An arc welding system with a robot and a rotating/tilting positioner is a major application area, where manual programming is a very tedious job. Off-line programming is a constructive way to solve the problem. The inverse kinematics algorithm of robot and positioner is the foundation of the off-line programming system. Although previously there were some researchers who studied the positioner inverse kinematics algorithm, they only focused on a special solution of the positioner inverse kinematics, which is the solution at down-hand welding position. However, in welding production, welding position other than down-hand position is also needed. A method for representing welding position was introduced. Then a general algorithm of rotating/tilting positioner inverse kinematics is presented.展开更多
Uncovering the role of environmental factors and finding critical factors which harbor significant fractions in governing microbial communities remain key questions in coastal marine systems.To detect the interactions...Uncovering the role of environmental factors and finding critical factors which harbor significant fractions in governing microbial communities remain key questions in coastal marine systems.To detect the interactions between environmental factors and distributions of virio-and bacterioplankton in trophic coastal areas,we used flow cytometry to investigate the abundance of virio-and bacterioplankton covering 31 stations in the Bohai Sea of China.Our results suggested that the average abundance of total virus(TV)in winter(~2.29×108 particles/mL)was slightly lower than in summer(~3.83×108 particles/mL).The mean total bacterial abundance(TB)was much lower in winter(~2.54×107 particles/mL)than in summer(~5.43×107 particles/mL).Correlation analysis via redundancy analysis(RDA)and network analysis among virioplankton,bacterioplankton and environmental factors revealed that the abundances of viral and bacterial subpopulations depend on environmental factors.In winter,only temperature significantly influenced the abundances of virio-and bacterioplankton.In summer,in addition to temperature,both salinity and nutrient(SiO2)had a remarkable impact on the distribution of virioand bacterioplankton.Our results showed a clear seasonal and trophic pattern throughout the whole water system,which revealed that temperature and eutrophication may play crucial roles in microbial distribution pattern.展开更多
As the base of the research work on the weld shape control during pulsed gas tungsten arc welding (GTAW) with wire filler, this paper addressed the modeling of the dynamic welding process. Topside length Lt, maximum...As the base of the research work on the weld shape control during pulsed gas tungsten arc welding (GTAW) with wire filler, this paper addressed the modeling of the dynamic welding process. Topside length Lt, maximum width Wt and half-length ratio Rh1 were selected to depict topside weld pool shape, and were measured on-line by vision sensing. A dynamic neural network model was constructed to predict the usually unmeasured backside width and topside height of the weld through topside shape parameters and welding parameters. The inputs of the model were the welding parameters (peak current, pulse duty ratio, welding speed, filler rate), the joint gap, the topside pool shape parameters (Lt, Wt, and Rh1), and their history values at two former pulse, a total of 24 numbers. The validating experiment results proved that the artificial neural network (ANN) model had high precision and could be used in process control. At last, with the developed dynamic model, steady and dynamic behavior was analyzed by simulation experiments, which discovered the variation rules of weld pool shape parameters under different welding parameters, and further knew well the characteristic of the welding process.展开更多
On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real tim...On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real time.Here we describe the development and application of an automatic measurement system that incorporates PM_(2.5)sampling,thermal desorption,atmospheric pressure photoionization,and UHRMS analysis.Molecular formulas of detected organic compounds were deducted from the accurate(±10 ppm)molecular weights obtained at a mass resolution of 100,000,allowing the identification of small organic compounds in PM_(2.5).Detection efficiencies of 28 standard compounds were determined and we found a high sensitivity and selectivity towards organic amines with limits of detection below 10 pg.As a proof of principle,PM_(2.5)samples collected off-line in winter in the urban area of Beijing were analyzed using the Ionization Module and HRMS of the system.The automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 hr.The detected organic compounds comprised mainly CHON and CHN compounds below 350 m/z.Pronounced seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in winter.This result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in summer.Diurnal variation in signal intensity of each formula provides crucial information to reveal its source and formation pathway.In summary,the automatic measurement system serves as an important tool for the on-line characterization and identification of organic species in PM_(2.5).展开更多
The synthetic parameters were changed to explore the formation mechanism of the oxygen-containing groups on the surfaces of the hypercrosslinked polymers. The FT-IR spectra and the Boehm titration were used to charact...The synthetic parameters were changed to explore the formation mechanism of the oxygen-containing groups on the surfaces of the hypercrosslinked polymers. The FT-IR spectra and the Boehm titration were used to characterize the surface chemistry of the synthesized polymers. The GC-MS was applied to analyze nitrobenzene which was the solvent in the reaction. The functionalities such as carbonyls and phenols were formed through the oxidation of residual chloromethyl groups by nitrobenzene and the carboxylic groups were formed through further oxidation by oxygen. The nitrobenzene was deoxidized to nitrosobenzene and further to aniline.展开更多
Global Cancer Statistics 2022 reported the prevalence and high mortality rate of lung cancer.Notably,non-small cell lung cancer(NSCLC)accounts for the majority of the histologic types1.Precision therapy for lung cance...Global Cancer Statistics 2022 reported the prevalence and high mortality rate of lung cancer.Notably,non-small cell lung cancer(NSCLC)accounts for the majority of the histologic types1.Precision therapy for lung cancer has progressed rapidly and immune checkpoint inhibitors(ICIs)have become a leading research topic.Indeed,ICI therapy has been shown to improve the prognosis of lung cancer patients.展开更多
Atrial fibrillation is of public health importance and profoundly increases morbidity, mortality and health-related expenditures. Morbidities include the increased risks of cardiovascular outcomes such as heart failur...Atrial fibrillation is of public health importance and profoundly increases morbidity, mortality and health-related expenditures. Morbidities include the increased risks of cardiovascular outcomes such as heart failure and stroke, and the deleterious effects on quality of life, functional status and cognition. Our purpose is to understand the molecular mechanism of atrial fibrillation, a model under pathological conditions should be established. Acetylcholine, a neurotransmitter in the vagus nerve, has been established with numerous atrial fibrillation models. We will discuss the established model of atrial fibrillation which induced by acetylcholine, aiming to seek a model which are more close to the clinical condition. The underlying mechanisms will be discussed in order to observe the mechanism of antiarrhythmic drugs.展开更多
Feature modeler of welded structure provides both 3D-geographical and non-geographical features for the off-line programming of arc welded robot. Welded structure is regarded as an assembly, the design of welded stru...Feature modeler of welded structure provides both 3D-geographical and non-geographical features for the off-line programming of arc welded robot. Welded structure is regarded as an assembly, the design of welded structure consists of three aspects f plane, joint, and groove design. Each aspect corresponds to a category of features. The plane features are defined by interactive feature definition. A method analogous to the 'mating feature' is introduced to represent the joint features. Based on AutoCAD 2000, a B-rep solid modeler, a prototype system is implemented.展开更多
文摘Objective: To research the effectiveness of ulinastatin in combination with continuous renal replacement therapy in treating sepsis acute kidney injury and its effect on systemic inflammation, immune function and miRAN expression. Methods: The 84 patients who were diagnosed with sepsis complicated by acute kidney injury in our hospital between May 2020 and June 2022 were chosen and randomly assigned to the study group (n = 42) and the control group (n = 42). Ulinastatin in combination with continuous renal replacement therapy was administered to the study group, whereas the control group was administered with continuous renal replacement therapy alone. Both groups’ clinical effects were observed. The levels of blood urea nitrogen (BUN), serum creatinine (SCr), tumor necrosis factor-α (TNF-α), high sensitivity Creactive protein (hs-CRP), vascular cell adhesion molecule-1 (VCAM-1), IgG, IgA, IgM, expression levels of miR-233 and miR-10a were compared among both the groups, pre-, and post-treatment. Results: The study group’s overall effectiveness rate was higher that is 95.24%, in comparison to the control group’s 78.57%, and this difference was statistically significant (P α, hs-CRP, VCAM-1, and miR-233 and miR-10a expression levels in both the study and control groups were decreased, however, the study group had reduced levels in comparison to the control group, with statistically significant differences (P P Conclusion: Ulinastatin in combination with continuous renal replacement therapy for treating sepsis acute kidney injury exhibits a positive effect and can significantly improve the systemic inflammation and immune function in patients.
基金supported by the National Key R&D Program (Grant Nos. 2017YFC0212603 and 2017YFC0212604)the Chinese Academy of Sciences Strategic Priority Research Program (Grant No. XDA19040201)the National Natural Science Foundation of China (Grant Nos. 41575128 and 41620104008)
文摘Severe haze pollution that occurred in January 2014 in Wuhan was investigated. The factors leading to Wuhan’s PM2.5 pollution and the characteristics and formation mechanism were found to be significantly different from other megacities, like Beijing. Both the growth rates and decline rates of PM2.5 concentrations in Wuhan were lower than those in Beijing, but the monthly PM2.5 value was approximately twice that in Beijing. Furthermore, the sharp increases of PM2.5 concentrations were often accompanied by strong winds. A high-precision modeling system with an online source-tagged method was established to explore the formation mechanism of five haze episodes. The long-range transport of the polluted air masses from the North China Plain (NCP) was the main factor leading to the sharp increases of PM2.5 concentrations in Wuhan, which contributed 53.4% of the monthly PM2.5 concentrations and 38.5% of polluted days. Furthermore, the change in meteorological conditions such as weakened winds and stable weather conditions led to the accumulation of air pollutants in Wuhan after the long-range transport. The contribution from Wuhan and surrounding cities to the PM2.5 concentrations was determined to be 67.4% during this period. Under the complex regional transport of pollutants from surrounding cities, the NCP, East China, and South China, the five episodes resulted in 30 haze days in Wuhan. The findings reveal important roles played by transregional and intercity transport in haze formation in Wuhan.
基金supported by the Jilin Province Science and Technology Department Key Research and Development Project(20200402094N C)。
文摘To evaluate the relationships among clones and open pollinated families from the same plus trees and to select elite breeding materials,growth,and wood characteristics of 33-year-old Pinus korainsis clones and families were measured and analyzed.The results show that growth and wood characters varied significantly.The variation due to clonal effects was higher than that of family effects.The ratio of genetic to phenotypic coefficient of variation of clones in growth and wood traits was above 90%,and the repeatability of these characteristics was more than 0.8,whereas the ratio of genetic to phenotypic coefficient of variation of families was above 90%.The broad-sense heritability of all characteristics exceeded 0.4,and the narrow-sense family heritability of growth traits was less than 0.3.Growth characteristics were positively correlated with each other,but most wood properties were weakly correlated in both clones and families.Fiber length and width were positively correlated between clones and families.Using the membership function method,eleven clones and four families were selected as superior material for improved diameter growth and wood production,and two families from clonal and open-pollinated trees showed consistently better performance.Generally,selection of the best clones is an effective alternative to deployment of families as the repeatability estimates from clonal trees were higher than narrow-sense heritability estimates from open pollinated families.The results provide valuable insight for improving P.koraiensis breeding programs and subsequent genetic improvement.
文摘Background: Developing a novel, efficient biomarker for detecting malignant tumors is essential for the early diagnosis of cancers. Our aim was to assess the diagnostic value of a potential plasma tumor marker, thioredoxin reductase (TR), which is expressed in many types of malignant tumor, for the non-invasive detection of cancers. Methods: The plasma activities of TR were measured in 1513 patients with common clinical diseases, 59 patients with benign tumors, and 154 patients with cancers and 586 healthy controls. The area under the ROC curve (AUC) of TR and logistic regression results of different groups were compared by sensitivity, specificity and Youden’s index. Diagnostic cut-offs and clinical reference intervals were established via ROC curve analysis. Results: The logistic regression indicated that TR activity can discriminate between cancers and benign tumors or other common diseases very well (p < 0.0001), with an area under the curve from the receiver-operator characteristics between 0.91 and 0.96. The positive critical value was 2.51 and the cancer critical value was 9.90. The diagnostic gray zone (2.51 - 9.90) may be associated with benign tumors and some common clinical diseases. Conclusions: As a novel potential marker of malignant tumors with quantitative evaluation of proliferation, TR activity detection has an excellent diagnostic potential for early-stage malignant tumors. Impact: The convenient, economical, relatively non-invasive, and reproducible detection method of TR activity makes it suitable for routine clinical practice.
基金This paper was supported by the National Natural Science Foundation of China (No. 59635160) and AdvancedUniversity Doctoral
文摘Off-line programming provides an essential link between CAD and CAM, whose development should result in greater use of robotic arc welding. An arc welding system with a robot and a rotating/tilting positioner is a major application area, where manual programming is a very tedious job. Off-line programming is a constructive way to solve the problem. The inverse kinematics algorithm of robot and positioner is the foundation of the off-line programming system. Although previously there were some researchers who studied the positioner inverse kinematics algorithm, they only focused on a special solution of the positioner inverse kinematics, which is the solution at down-hand welding position. However, in welding production, welding position other than down-hand position is also needed. A method for representing welding position was introduced. Then a general algorithm of rotating/tilting positioner inverse kinematics is presented.
基金The National Basic Research Program(973 Program)of China under contract No.2015CB453300the Strategic Priority Research Programme of Chinese Academic of Sciences under contract No.XDA11020403+2 种基金the Key Research Project of Frontier Science of Chinese Academy of Sciences under contract No.QYZDB-SSW-DQC041the Technology Service Network Plan of Chinese Academy of Sciences under contract No.STS,ZSYS-006the External Cooperation Program of Chinese Academy of Sciences(supported by the Bureau of International Cooperation,the Chinese Academy of Sciences)under contract No.133337KYSB20180015。
文摘Uncovering the role of environmental factors and finding critical factors which harbor significant fractions in governing microbial communities remain key questions in coastal marine systems.To detect the interactions between environmental factors and distributions of virio-and bacterioplankton in trophic coastal areas,we used flow cytometry to investigate the abundance of virio-and bacterioplankton covering 31 stations in the Bohai Sea of China.Our results suggested that the average abundance of total virus(TV)in winter(~2.29×108 particles/mL)was slightly lower than in summer(~3.83×108 particles/mL).The mean total bacterial abundance(TB)was much lower in winter(~2.54×107 particles/mL)than in summer(~5.43×107 particles/mL).Correlation analysis via redundancy analysis(RDA)and network analysis among virioplankton,bacterioplankton and environmental factors revealed that the abundances of viral and bacterial subpopulations depend on environmental factors.In winter,only temperature significantly influenced the abundances of virio-and bacterioplankton.In summer,in addition to temperature,both salinity and nutrient(SiO2)had a remarkable impact on the distribution of virioand bacterioplankton.Our results showed a clear seasonal and trophic pattern throughout the whole water system,which revealed that temperature and eutrophication may play crucial roles in microbial distribution pattern.
基金This work was supported by the National Natural Sci-ence Foundation of China(Grant No.59635160)the Weapon Pre-Research Foundation of China(Grant No.51418050404HT0159).
文摘As the base of the research work on the weld shape control during pulsed gas tungsten arc welding (GTAW) with wire filler, this paper addressed the modeling of the dynamic welding process. Topside length Lt, maximum width Wt and half-length ratio Rh1 were selected to depict topside weld pool shape, and were measured on-line by vision sensing. A dynamic neural network model was constructed to predict the usually unmeasured backside width and topside height of the weld through topside shape parameters and welding parameters. The inputs of the model were the welding parameters (peak current, pulse duty ratio, welding speed, filler rate), the joint gap, the topside pool shape parameters (Lt, Wt, and Rh1), and their history values at two former pulse, a total of 24 numbers. The validating experiment results proved that the artificial neural network (ANN) model had high precision and could be used in process control. At last, with the developed dynamic model, steady and dynamic behavior was analyzed by simulation experiments, which discovered the variation rules of weld pool shape parameters under different welding parameters, and further knew well the characteristic of the welding process.
基金supported by the National Natural Science Foundation of China(No.41805105)。
文摘On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real time.Here we describe the development and application of an automatic measurement system that incorporates PM_(2.5)sampling,thermal desorption,atmospheric pressure photoionization,and UHRMS analysis.Molecular formulas of detected organic compounds were deducted from the accurate(±10 ppm)molecular weights obtained at a mass resolution of 100,000,allowing the identification of small organic compounds in PM_(2.5).Detection efficiencies of 28 standard compounds were determined and we found a high sensitivity and selectivity towards organic amines with limits of detection below 10 pg.As a proof of principle,PM_(2.5)samples collected off-line in winter in the urban area of Beijing were analyzed using the Ionization Module and HRMS of the system.The automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 hr.The detected organic compounds comprised mainly CHON and CHN compounds below 350 m/z.Pronounced seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in winter.This result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in summer.Diurnal variation in signal intensity of each formula provides crucial information to reveal its source and formation pathway.In summary,the automatic measurement system serves as an important tool for the on-line characterization and identification of organic species in PM_(2.5).
文摘The synthetic parameters were changed to explore the formation mechanism of the oxygen-containing groups on the surfaces of the hypercrosslinked polymers. The FT-IR spectra and the Boehm titration were used to characterize the surface chemistry of the synthesized polymers. The GC-MS was applied to analyze nitrobenzene which was the solvent in the reaction. The functionalities such as carbonyls and phenols were formed through the oxidation of residual chloromethyl groups by nitrobenzene and the carboxylic groups were formed through further oxidation by oxygen. The nitrobenzene was deoxidized to nitrosobenzene and further to aniline.
基金the Hunan Lung Cancer Clinical Medical Research Center(Grant No.2023SK4024 to LW)the Hunan Science and Technology Innovation Program(Grant No.2021SK51121 to LW)the Hunan Cancer Hospital Climb plan(Grant No.ZX2020005-5 to LW)。
文摘Global Cancer Statistics 2022 reported the prevalence and high mortality rate of lung cancer.Notably,non-small cell lung cancer(NSCLC)accounts for the majority of the histologic types1.Precision therapy for lung cancer has progressed rapidly and immune checkpoint inhibitors(ICIs)have become a leading research topic.Indeed,ICI therapy has been shown to improve the prognosis of lung cancer patients.
文摘Atrial fibrillation is of public health importance and profoundly increases morbidity, mortality and health-related expenditures. Morbidities include the increased risks of cardiovascular outcomes such as heart failure and stroke, and the deleterious effects on quality of life, functional status and cognition. Our purpose is to understand the molecular mechanism of atrial fibrillation, a model under pathological conditions should be established. Acetylcholine, a neurotransmitter in the vagus nerve, has been established with numerous atrial fibrillation models. We will discuss the established model of atrial fibrillation which induced by acetylcholine, aiming to seek a model which are more close to the clinical condition. The underlying mechanisms will be discussed in order to observe the mechanism of antiarrhythmic drugs.
基金supported by the National Natural Science Foundation of China(No.59635160)Advanced University Doctoral Subject Foundation(No.98021311)
文摘Feature modeler of welded structure provides both 3D-geographical and non-geographical features for the off-line programming of arc welded robot. Welded structure is regarded as an assembly, the design of welded structure consists of three aspects f plane, joint, and groove design. Each aspect corresponds to a category of features. The plane features are defined by interactive feature definition. A method analogous to the 'mating feature' is introduced to represent the joint features. Based on AutoCAD 2000, a B-rep solid modeler, a prototype system is implemented.