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Serum proteins differentially expressed in gestational diabetes mellitus assessed using isobaric tag for relative and absolute quantitation proteomics 被引量:1
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作者 Wei-Li Cao Cui-Ping Yu Ling-Li Zhang 《World Journal of Clinical Cases》 SCIE 2024年第8期1395-1405,共11页
BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients a... BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients and their altered expression in the serum,proteomics techniques were deployed to detect the differentially expressed proteins(DEPs)of in the serum of GDM patients to further explore its pathogenesis,and find out possible biomarkers to forecast GDM occurrence.METHODS Subjects were divided into GDM and normal control groups according to the IADPSG diagnostic criteria.Serum samples were randomly selected from four cases in each group at 24-28 wk of gestation,and the blood samples were identified by applying iTRAQ technology combined with liquid chromatography-tandem mass spectrometry.Key proteins and signaling pathways associated with GDM were identified by bioinformatics analysis,and the expression of key proteins in serum from 12 wk to 16 wk of gestation was further verified using enzyme-linked immunosorbent assay (ELISA).RESULTS Forty-seven proteins were significantly differentially expressed by analyzing the serum samples between the GDMgravidas as well as the healthy ones. Among them, 31 proteins were found to be upregulated notably and the rest16 proteins were downregulated remarkably. Bioinformatic data report revealed abnormal expression of proteinsassociated with lipid metabolism, coagulation cascade activation, complement system and inflammatory responsein the GDM group. ELISA results showed that the contents of RBP4, as well as ANGPTL8, increased in the serumof GDM gravidas compared with the healthy ones, and this change was found to initiate from 12 wk to 16 wk ofgestation.CONCLUSION GDM symptoms may involve abnormalities in lipid metabolism, coagulation cascade activation, complementsystem and inflammatory response. RBP4 and ANGPTL8 are expected to be early predictors of GDM. 展开更多
关键词 Gestational diabetes mellitus Liquid chromatography-tandem mass spectrometry Isobaric tag for relative and absolute quantitation PROTEOMICS BIOMARKER
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Euler Product Expressions of Absolute Tensor Products of Dirichlet L-Functions
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作者 Hidenori Tanaka Shin-ya Koyama 《Advances in Pure Mathematics》 2024年第6期451-486,共36页
In this paper, we calculate the absolute tensor square of the Dirichlet L-functions and show that it is expressed as an Euler product over pairs of primes. The method is to construct an equation to link primes to a se... In this paper, we calculate the absolute tensor square of the Dirichlet L-functions and show that it is expressed as an Euler product over pairs of primes. The method is to construct an equation to link primes to a series which has the factors of the absolute tensor product of the Dirichlet L-functions. This study is a generalization of Akatsuka’s theorem on the Riemann zeta function, and gives a proof of Kurokawa’s prediction proposed in 1992. 展开更多
关键词 Dirichlet L-Function absolute Tensor Product (Kurokawa Tensor Product) Euler Product
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Absolute Wall Thickness Measurement of Conducting Plates Using Pulsed Eddy Currents
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作者 Victor-O. de Haan Riccardo Scottini 《Journal of Electromagnetic Analysis and Applications》 2024年第3期25-41,共17页
The method using pulsed eddy currents to determine the thickness of a conduction plate is extended to enable the simultaneous measurement of the plate thickness and material properties. For optimal performance, a prob... The method using pulsed eddy currents to determine the thickness of a conduction plate is extended to enable the simultaneous measurement of the plate thickness and material properties. For optimal performance, a probe must be designed depending on the thickness range that should be accessible. The need for a calibration of the material properties of a conducting plate to enable the measurement of its thickness has been removed. All that is needed is a probe with known dimensions and suitable hardware to create a current pulse and measure a transient magnetic induction. 展开更多
关键词 Pulsed Eddy Currents Wall Thickness absolute and Relative Measurements
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First acceptance testing of multiple A10 absolute gravimeters in China and analysis of the comparison results 被引量:2
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作者 Xiaotong Zhang Hao Zhou +4 位作者 Ying Jiang Dulin Zhai Gongzhe Wei Hui Li Ziwei Liu 《Geodesy and Geodynamics》 EI CSCD 2023年第4期401-410,共10页
Three A10 absolute gravimeters(AGs) were first acquired in China by the Hubei Earthquake Agency under the Belt and Road Seismic Monitoring Network Project. Although AG measuring and testing technique is not new, the p... Three A10 absolute gravimeters(AGs) were first acquired in China by the Hubei Earthquake Agency under the Belt and Road Seismic Monitoring Network Project. Although AG measuring and testing technique is not new, the purchase and simultaneous testing of 3 A10 absolute gravimeters is unprecedented in China. This study conducted the first acceptance testing of the AGs at 3 locations(the Jiufengshan Gravity Observation Station, the Global Navigation Satellite System Observation Station in Wuhan, and the Jiugongshan Observation Station in Xianning). The results were compared using a method based on expert validation, and the acceptance testing scheme was formulated by referring to the Technical Regulations for Tectonic Environment Monitoring Networks in China and Specifications for Gravimetry Control. Based on the repeatability, precision, and consistency of the measured g values, the results from each instrument were evaluated using the air pressure precision test. Comparing the instrument reference values, the final test results can identify the indicator parameters for 3 A10 AGs, the effects of the surrounding environment, and the related parameters on measurement precision. The precision of A10-059, A10-058, and A10-057 exceeded 0.78 μGal, 0.79 μGal, and 0.42 μGal, respectively.This testing scheme can be used as a reference for conducting acceptance testing of AGs in the future and obtaining absolute gravimetric measurements. 展开更多
关键词 Gravitational acceleration Comparison of absolute gravimeters A10 absolute gravimeters Instrument precision
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Deep learning enabled single-shot absolute phase recovery in high-speed composite fringe pattern profilometry of separated objects
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作者 Maciej Trusiak Malgorzata Kujawinska 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第12期1-4,共4页
A recent article in the Opto-Electronic Advances(OEA)journal from Prof.Qian Chen and Prof.Chao Zuo’s group introduced a new and efficient 3D imaging system that captures high-speed images using deep learning-enabled ... A recent article in the Opto-Electronic Advances(OEA)journal from Prof.Qian Chen and Prof.Chao Zuo’s group introduced a new and efficient 3D imaging system that captures high-speed images using deep learning-enabled fringe projection profilometry(FPP).In this News&Views article,we explore potential avenues for future advancements,including expanding the measurement range through an extended number-theoretical approach,enhancing quality through the incorporation of horizontal fringes,and integrating data from other modalities to broaden the system's applications. 展开更多
关键词 system absolute SEPARATED
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Optimal zero-crossing group selection method of the absolute gravimeter based on improved auto-regressive moving average model
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作者 牟宗磊 韩笑 胡若 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期347-354,共8页
An absolute gravimeter is a precision instrument for measuring gravitational acceleration, which plays an important role in earthquake monitoring, crustal deformation, national defense construction, etc. The frequency... An absolute gravimeter is a precision instrument for measuring gravitational acceleration, which plays an important role in earthquake monitoring, crustal deformation, national defense construction, etc. The frequency of laser interference fringes of an absolute gravimeter gradually increases with the fall time. Data are sparse in the early stage and dense in the late stage. The fitting accuracy of gravitational acceleration will be affected by least-squares fitting according to the fixed number of zero-crossing groups. In response to this problem, a method based on Fourier series fitting is proposed in this paper to calculate the zero-crossing point. The whole falling process is divided into five frequency bands using the Hilbert transformation. The multiplicative auto-regressive moving average model is then trained according to the number of optimal zero-crossing groups obtained by the honey badger algorithm. Through this model, the number of optimal zero-crossing groups determined in each segment is predicted by the least-squares fitting. The mean value of gravitational acceleration in each segment is then obtained. The method can improve the accuracy of gravitational measurement by more than 25% compared to the fixed zero-crossing groups method. It provides a new way to improve the measuring accuracy of an absolute gravimeter. 展开更多
关键词 absolute gravimeter laser interference fringe Fourier series fitting honey badger algorithm mul-tiplicative auto-regressive moving average(MARMA)model
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Influence of Non-Natural Ageing Temperature on the Microstructural Characteristics and Mechanical Properties of Cast Aluminum 6063 Alloy
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作者 Oluwole Oladele Ayodele Adedeke +1 位作者 Olajesu Olanrewaju Samuel Olusunle 《Journal of Minerals and Materials Characterization and Engineering》 2024年第2期91-99,共9页
This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and ... This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and machined into tensile and impact test samples before carrying out solution heat treatment at 550?C (0.83 T<sub>m</sub>) on two parts of the samples while retaining one part as the control. The two parts were further divided into sets denoted A and B and were aged at 180?C (0.27 T<sub>m</sub>) and 160?C (0.24 T<sub>m</sub>), respectively, for 12 hours. The results showed that sample A has the optimal yield strength and ultimate tensile strength of 192 and 206 MPa, respectively. Likewise, the sample gave the highest impact strength value of about 9.63 J/mm<sup>2</sup>. The observed results were supported by the optical micrograph, which revealed that the sample has evenly dispersed precipitates in its microstructure. This is deemed responsible for the observed increase in strength of the sample. 展开更多
关键词 Aluminum Alloy non-natural Ageing Mechanical Properties Microstructural Features
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Research of the wave measurement using GPS absolute velocity estimation technology 被引量:3
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作者 单瑞 刘焱雄 +2 位作者 赵铁虎 张晓波 秦轲 《Marine Science Bulletin》 CAS 2013年第2期59-70,共12页
This paper analyzed the existing methods of wave measurement, and described the advantages of GPS applied in measuring the wave. The equations of absolute velocity estimation were discussed, focusing on two methods wi... This paper analyzed the existing methods of wave measurement, and described the advantages of GPS applied in measuring the wave. The equations of absolute velocity estimation were discussed, focusing on two methods with Doppler shill. The error sources and their effect on velocity estimation were analyzed. Then, some tests were carried on to simulate dynamic velocity determination using static data Based on the high-frequency carrier-phase derived Doppler observations, the velocity has been estimated to the precision of 1 cm/s or so, even to the mm/s level. And with the receiver generated Doppler measurements, the precision can reach 3 - 15 cm/s. 展开更多
关键词 GPS absolute velocity estimation Doppler observation wavemeasurement error analysis
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New criterion for delay-dependent absolute stability of Lurie system with interval time-varying delay 被引量:1
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作者 薛明香 费树岷 +1 位作者 李涛 潘俊涛 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期375-378,共4页
The delay-dependent absolute stability for a class of Lurie systems with interval time-varying delay is studied. By employing an augmented Lyapunov functional and combining a free-weighting matrix approach and the rec... The delay-dependent absolute stability for a class of Lurie systems with interval time-varying delay is studied. By employing an augmented Lyapunov functional and combining a free-weighting matrix approach and the reciprocal convex technique, an improved stability condition is derived in terms of linear matrix inequalities (LMIs). By retaining some useful terms that are usually ignored in the derivative of the Lyapunov function, the proposed sufficient condition depends not only on the lower and upper bounds of both the delay and its derivative, but it also depends on their differences, which has wider application fields than those of present results. Moreover, a new type of equality expression is developed to handle the sector bounds of the nonlinear function, which achieves fewer LMIs in the derived condition, compared with those based on the convex representation. Therefore, the proposed method is less conservative than the existing ones. Simulation examples are given to demonstrate the validity of the approach. 展开更多
关键词 Lurie system reciprocal convex technique absolute stability interval time-varying delay linear matrix inequality (LMI)
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MULTIVARIATE ABSOLUTE DEGREE OF GREY INCIDENCE BASED ON DISTRIBUTION CHARACTERISTICS OF POINTS
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作者 张可 王岩 +1 位作者 辛江慧 许叶军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期145-151,共7页
The analysis result of absolute degree of grey incidence for multivariate time series is often inconsistent with the qualitative analysis. To overcome this shortage, a multivariate absolute degree of grey incidence ba... The analysis result of absolute degree of grey incidence for multivariate time series is often inconsistent with the qualitative analysis. To overcome this shortage, a multivariate absolute degree of grey incidence based on distribution characteristics of points is proposed. Based on the geometric description of multivariate time se- ries, the neighborhood extrema are extracted in the different regions, and a characteristic point set is constructed. Then according to the distribution of the characteristic point set, a characteristic point sequence reflecting the ge- ometric features of multivariate time series is obtained. The incidence analysis between multivariate time series is transformed into the relational analysis between characteristic point sequences, and a grey incidence model is established. The model possesses the properties of translational invariance, transpose and rank transform invari- ance, and satisfies the grey incidence analysis axioms. Finally, two cases are studied and the results prove the ef- fectiveness of the model. 展开更多
关键词 grey system absolute degree of grey incidences multivariate time series similarity measure
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Absolute Exponential Stability of Generalized Dynamical Neural Networks
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作者 孙长银 费树岷 冯纯伯 《Journal of Southeast University(English Edition)》 EI CAS 2002年第2期159-163,共5页
This paper investigates the absolute exponential stability of generalized neural networks with a general class of partially Lipschitz continuous and monotone increasing activation functions. The main obtained result i... This paper investigates the absolute exponential stability of generalized neural networks with a general class of partially Lipschitz continuous and monotone increasing activation functions. The main obtained result is that if the interconnection matrix T of the neural system satisfies that - T is an H matrix with nonnegative diagonal elements, then the neural system is absolutely exponentially stable(AEST). The Hopfield network, Cellular neural network and Bidirectional associative memory network are special cases of the network model considered in this paper. So this work gives some improvements to the previous ones. 展开更多
关键词 absolute exponential stability partial Lipschitz continuity neural networks
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极性强化词的语义走向——以absolutely为例
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作者 黄蓓 《长春大学学报》 2013年第7期851-855,共5页
以absolutely为例,结合共时与历时主观化框架,对英语极性强化词的语义演化路径加以追踪,发现abso-lutely的意义体现了客观义<主观义<交互主观义的单向演进趋势。对照汉语对应成分"极",可以发现英汉对应范畴在语义演化... 以absolutely为例,结合共时与历时主观化框架,对英语极性强化词的语义演化路径加以追踪,发现abso-lutely的意义体现了客观义<主观义<交互主观义的单向演进趋势。对照汉语对应成分"极",可以发现英汉对应范畴在语义演化路径上存在一定的共通性。 展开更多
关键词 极性强化词 语义走向 absolutely “极” 主观化
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Empirical Bayes Absolute Error Loss Estimation for Parameter of One-Side Truncation Distribution Families
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作者 李金平 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期20-22,共3页
In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0&... In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0<λ,r≤1,Mn≤lnln n (for large n),Mn→∞ as n→∞. 展开更多
关键词 one-side truncation distribution families absolute error loss function empirical Bayes estimator convergence rates
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契合理念下Absolut绝对伏特加酒包装设计探究
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作者 柳林 柳漪 《艺术科技》 2023年第12期159-161,共3页
绝对伏特加作为西方酒品牌的重要组成部分,拥有“纯净、简单、完美”的产品理念,因纯正的口感、简约的瓶身设计及包装设计积累了众多忠实的青年粉丝。其经典之处还包含广告创意,以瓶身的样式为符号,出现于海报、宣传片中,打造了一套完整... 绝对伏特加作为西方酒品牌的重要组成部分,拥有“纯净、简单、完美”的产品理念,因纯正的口感、简约的瓶身设计及包装设计积累了众多忠实的青年粉丝。其经典之处还包含广告创意,以瓶身的样式为符号,出现于海报、宣传片中,打造了一套完整的Absolut文化概念。近年来我国酒水饮料消费额不断攀登,原因在于新一代年轻消费者逐渐成为其主要消费群体,酒文化拥有了新的诠释,除了具备社交属性外,还具有艺术性与时尚性。对与互联网一起成长的新一代消费者而言,性价比不再是购买酒时的最主要依据,这类消费群体懂得享受生活,更注重生活品质及自身品位,对美的理解和把握更深入,因此对品牌及产品的要求更加苛刻。产品的包装设计是消费者最先接触且最直接的视觉形象载体,面临升级需求。文章基于契合理念研究绝对伏特加品牌的酒包装设计,从物理功能和精神功能两个方面出发,将契合理念应用到酒包装设计中。在不改变经典瓶身样式的前提下进行结构性的设计改造,对绝对伏特加在市场中的营销活动加以研究与分析,配合当下在青年群体中流行的“便利店调酒”文化,进行以增强趣味性和互动性为目的的设计探索。 展开更多
关键词 绝对伏特加 absolut 包装设计 契合理念
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Review of low timing jitter mode-locked fiber lasers and applications in dual-comb absolute distance measurement 被引量:9
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作者 Haosen Shi Youjian Song +6 位作者 Runmin Li Yuepeng Li Hui Cao Haochen Tian Bowen Liu Lu Chai Minglie Hu 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2018年第4期205-217,共13页
Passively mode-locked fiber lasers emit femtosecond pulse trains with excellent short-term stability. The quantum-limited timing jitter of a free running femtosecond erbium-doped fiber laser working at room temperatur... Passively mode-locked fiber lasers emit femtosecond pulse trains with excellent short-term stability. The quantum-limited timing jitter of a free running femtosecond erbium-doped fiber laser working at room temperature is considerably below one femtosecond at high Fourier frequency. The ultrashort pulse train with ultralow timing jitter enables absolute time-of-flight measurements based on a dual-comb implementation, which is typically composed of a pair of optical frequency combs generated by femtosecond lasers. Dead-zone-free absolute distance measurement with sub-micrometer precision and kHz update rate has been routinely achieved with a dual-comb configuration, which is promising for a number of precision manufacturing applications, from large step-structure measurements prevalent in microelectronic profilometry to three coordinate measurements in large-scale aerospace manufacturing and shipbuilding. In this paper, we first review the sub-femtosecond precision timing jitter characterization methods and approaches for ultralow timing jitter mode-locked fiber laser design. Then, we provide an overview of the state-of-the-art dual-comb absolute ranging technology in terms of working principles, experimental implementations, and measurement precisions. Finally, we discuss the impact of quantum-limited timing jitter on the dual-comb ranging precision at a high update rate. The route to highprecision dual-comb range finder design based on ultralow jitter femtosecond fiber lasers is proposed. 展开更多
关键词 TIMING JITTER MODE-LOCKED lasers Dual-comb absolute distance measurement
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Absolute monocyte and lymphocyte count prognostic score for patients with gastric cancer 被引量:6
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作者 Wan Kyu Eo Da Wun Jeong +11 位作者 Hye Jung Chang Kyu Yeoun Won Sung Il Choi Se Hyun Kim Sung Wook Chun Young Lim Oh Tae Hwa Lee Young Ok Kim Ki Hyung Kim Yong Il Ji Ari Kim Heung Yeol Kim 《World Journal of Gastroenterology》 SCIE CAS 2015年第9期2668-2676,共9页
AIM:To measure the prognostic significance of absolute monocyte count/absolute lymphocyte count prognostic score(AMLPS) in patients with gastric cancer.METHODS:We retrospectively examined the combination of absolute m... AIM:To measure the prognostic significance of absolute monocyte count/absolute lymphocyte count prognostic score(AMLPS) in patients with gastric cancer.METHODS:We retrospectively examined the combination of absolute monocyte count(AMC) and absolute lymphocyte count(ALC) as prognostic variables in a cohort of 299 gastric cancer patients who underwent surgical resection between 2006 and 2013 and were followed at a single institution.Both AMC and ALC were dichotomized into two groups using cut-off points determined by receiving operator characteristic curve analysis.An AMLPS was generated,which stratified patients into three risk groups:low risk(both low AMC and high ALC),intermediate risk(either high AMC or low ALC),and high risk(both high AMC and low ALC).The primary objective of the study was to validate the impact of AMLPS on both disease-free survival(DFS) and overall survival(OS),and the second objective was to assess the AMLPS as an independent prognostic factor for survival in comparison with known prognostic factors.RESULTS:Using data from the entire cohort,the most discriminative cut-off values of AMC and ALC selected on the receiver operating characteristic curve were 672.4/μL and 1734/μL for DFS and OS.AMLPS risk groups included 158(52.8%) patients in the lowrisk,128(42.8%) in the intermediate-risk,and 13(4.3%) in the high-risk group.With a median followup of 37.2 mo(range:1.7-91.4 mo),five-year DFS rates in the low-,intermediate-,and high-risk groups were 83.4%,78.7%,and 19.8%,respectively.And fiveyear OS rates in the low-,intermediate-,and high-risk groups were 89.3%,81.1%,and 14.4%,respectively.On multivariate analysis performed with patient- and tumor-related factors,we identified AMLPS,age,and pathologic tumor-node-metastasis stage as the most valuable prognostic factors impacting DFS and OS.CONCLUSION:AMLPS identified patients with a poor DFS and OS,and it was independent of age,pathologic stage,and various inflammatory markers. 展开更多
关键词 MONOCYTES absolute LYMPHOCYTE COUNT STOMACH neopla
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Effects of Electric Stimulations Applied during Absolute Refractory Period on Cardiac Function of Rabbits with Heart Failure 被引量:5
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作者 张海柱 崔长琮 胡大一 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第2期155-158,共4页
The effects of electric currents applied during absolute refractory period (ARP) on the cardiac function of rabbits with heart failure due to myocardial infarction (MI), and the safety of this method were investig... The effects of electric currents applied during absolute refractory period (ARP) on the cardiac function of rabbits with heart failure due to myocardial infarction (MI), and the safety of this method were investigated. Thirty rabbits were randomly assigned equally to 3 groups: sham-operated group, LV-anterior wall cardiac contractility modulation (LV-CCM) group, and septum-CCM (S-CCM) group. A thoracotomy was performed on all the rabbits. Electric pulses were delivered during the ARP on the anterior wall of left ventricle in CCM group and in the septum in S-CCM group, respectively. The left ventricular systolic pressure (LVSP) and maximum positive left ventricular pressure change (+dp/dtmax), heart rates, ventricular tachycardia, ventricular fibrillation were observed. It was found that, as compared with the baseline, LVSP, and +dp/dtmax were significantly increased, on average, by 15.2% and 19.5% in LV-CCM group (P〈0,05), and by 8.5% and 10.8% in S-CCM group (P〈0.05). LVEDP was significantly decreased and -dp/dtmx increased both in LV-CCM group and S-CCM group (P〈0.05). CCM had no effect on heart rate and induced no arrhythmia in short time. It is concluded that electric currents delivered during the ARP could significantly enhance the contractility of myocardium safely, suggesting that CCM stimulation is a novel potent method for contractility modulation. 展开更多
关键词 HEMODYNAMICS absolute refractory period electric stimulation RABBIT
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LMI approach for absolute stability of general neutral type Lurie indirect control systems 被引量:5
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作者 Bingji XU Qun WANG 《控制理论与应用(英文版)》 EI 2005年第4期387-392,共6页
This paper deals with the problem of the absolute stability for general neutral type Lurie indirect control systems by Lyapunov method and linear matrix inequality (LMI) technique. Delay-dependent sufficient conditi... This paper deals with the problem of the absolute stability for general neutral type Lurie indirect control systems by Lyapunov method and linear matrix inequality (LMI) technique. Delay-dependent sufficient conditions for the absolute stability are derived and expressed as the feasibility problem of LMI, which can be easily solved by Matlab Toolbox. Finally, some examples are provide to demonstrate the effectiveness of proposed method. 展开更多
关键词 Lyapunov functional Lurie indirect control systems absolute stability LMI
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Deployment dynamics of a simplified spinning IKAROS solar sail via absolute coordinate based method 被引量:14
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作者 Jing Zhao Hai-Yan Hu Qiang Tian 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第1期132-142,共11页
The spinning solar sail of large scale has been well developed in recent years. Such a solar sail can be considered as a rigid-flexible multibody system mainly composed of a spinning central rigid hub, a number of fle... The spinning solar sail of large scale has been well developed in recent years. Such a solar sail can be considered as a rigid-flexible multibody system mainly composed of a spinning central rigid hub, a number of flexible thin tethers, sail membranes, and tip masses. A simplified interplanetary kite-craft accelerated by radiation of the Sun (IKAROS) model is established in this study by using the absolute-coordinate-based (ACB) method that combines the natural coordinate formulation (NCF) describing the central rigid hub and the absolute nodal coordinate formulation (ANCF) describing flexible parts. The initial configuration of the system in the second-stage deployment is determined through both dynamic and static analyses. The huge set of stiff equations of system dynamics is solved by using the generalized-alpha method, and thus the deployment dynamics of the system can be well understood. 展开更多
关键词 Solar sail · Spinning deployment - Natural coordinate formulation absolute nodal coordinate formulation
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Analysis of Absolute Stability for Time-delay Teleoperation Systems 被引量:4
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作者 Qi-Wen Deng Qing Wei Ze-Xiang Li 《International Journal of Automation and computing》 EI 2007年第2期203-207,共5页
In this paper, a new bilateral control algorithm based on absolute stability theory is put forward, which aims at the time-delay teleoperation system with force feedback from the slave directly. In the new control alg... In this paper, a new bilateral control algorithm based on absolute stability theory is put forward, which aims at the time-delay teleoperation system with force feedback from the slave directly. In the new control algorithm, the delay-dependent stability, instead of delay-independent stability, is taken as the aim of control design. It improves the transparency of the system at the price of unnecessary stability. With this algorithm, the time-delay teleoperation systems have good transparency and stability. A simulation system is established to verify the effect of this algorithm. 展开更多
关键词 TIME-DELAY STABILITY TRANSPARENCY absolutely stability delay-dependent stability.
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