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Storage time affects the level and diagnostic efficacy of plasma biomarkers for neurodegenerative diseases
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作者 Lifang Zhao Mingkai Zhang +4 位作者 Qimeng Li Xuemin Wang Jie Lu Ying Han Yanning Cai 《Neural Regeneration Research》 SCIE CAS 2025年第8期2373-2381,共9页
Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is k... Several promising plasma biomarker proteins,such as amyloid-β(Aβ),tau,neurofilament light chain,and glial fibrillary acidic protein,are widely used for the diagnosis of neurodegenerative diseases.However,little is known about the long-term stability of these biomarker proteins in plasma samples stored at-80°C.We aimed to explore how storage time would affect the diagnostic accuracy of these biomarkers using a large cohort.Plasma samples from 229 cognitively unimpaired individuals,encompassing healthy controls and those experiencing subjective cognitive decline,as well as 99 patients with cognitive impairment,comprising those with mild cognitive impairment and dementia,were acquired from the Sino Longitudinal Study on Cognitive Decline project.These samples were stored at-80°C for up to 6 years before being used in this study.Our results showed that plasma levels of Aβ42,Aβ40,neurofilament light chain,and glial fibrillary acidic protein were not significantly correlated with sample storage time.However,the level of total tau showed a negative correlation with sample storage time.Notably,in individuals without cognitive impairment,plasma levels of total protein and tau phosphorylated protein threonine 181(p-tau181)also showed a negative correlation with sample storage time.This was not observed in individuals with cognitive impairment.Consequently,we speculate that the diagnostic accuracy of plasma p-tau181 and the p-tau181 to total tau ratio may be influenced by sample storage time.Therefore,caution is advised when using these plasma biomarkers for the identification of neurodegenerative diseases,such as Alzheimer's disease.Furthermore,in cohort studies,it is important to consider the impact of storage time on the overall results. 展开更多
关键词 Alzheimer’s disease amyloid-β diagnostic ability glial fibrillary acidic protein NEURODEGENERATION neurofilament light chain plasma biomarkers single molecule array storage time tau
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Real-Time Information System of Power Plant Based on B/S Computing Mode 被引量:2
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作者 徐治皋 高正平 司风琪 《Journal of Southeast University(English Edition)》 EI CAS 2002年第1期80-83,共4页
This paper introduces the system structure and work principle of the upgraded real time information system in Wangting Power Plant, and then expounds the realization way and function features of this system on B/S co... This paper introduces the system structure and work principle of the upgraded real time information system in Wangting Power Plant, and then expounds the realization way and function features of this system on B/S computing mode. The results of field application show the new system has good capability, reliability and expandability. 展开更多
关键词 power plant real time information system B/s mode DCs
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NEURAL NETWORK SMITH PREDICTIVE CONTROL FOR TELEROBOTS WITH TIME DELAY 被引量:3
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作者 黄金泉 徐亮 Frank L Lewis 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第1期35-40,共6页
A neural network Smith predictive control strategy is proposed to deal with inpu t and feedback time delays in telerobot systems. The delay time is assumed to b e invariant and unknown. The proposed control structure... A neural network Smith predictive control strategy is proposed to deal with inpu t and feedback time delays in telerobot systems. The delay time is assumed to b e invariant and unknown. The proposed control structure consists of a slave syst em and a master controller. In the slave system, a recurrent neural network (RNN ) with on-line weight tuning algorithm is employed to approximate the dynamics of the time-delay-free nonlinear plant, which is used to linearize the slave s ystem. The master controller is a Smith predictor for the linearized slave syste m, which provides prediction and maintains the desirable tracking performance. S tability propriety is guaranteed based on the Lyapunov method. A simulation of a two-link robotic manipulator is provided to illustrate the effectiveness of th e proposed control strategy. 展开更多
关键词 TELEROBOT time delay s ystem neural networks smith predictor
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FUZZY ROBUST H_∞ CONTROL OF UNCERTAIN NONLINEAR SYSTEM WITH TIME-DEALY 被引量:3
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作者 刘亚 胡寿松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期123-126,共4页
This paper addresses the problem of the fuzzy H ∞state feedback control for a class of uncertain nonlinear systems with time delay. The Takagi Sugeno (T S) mo del with time delay and parameter uncertainties is ... This paper addresses the problem of the fuzzy H ∞state feedback control for a class of uncertain nonlinear systems with time delay. The Takagi Sugeno (T S) mo del with time delay and parameter uncertainties is adopted for modeling of nonlinear system. The systematic design procedure for the fuzzy robust controller based on linear matrix inequality (LMI) is given. Some sufficient conditions are derived for the existence of fuzzy H ∞ state feedback controllers such that the closed loop system is asymptotically stable and the effect of the disturbance input on controlled output is reduced to a prescribed level. An example is given to demonstrate the effectiveness of the proposed method. 展开更多
关键词 UNCERTAINTY time delay T s fuzzy model linear matrix inequality (LMI)
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Love Is Intensified by Absence- Book Review on "The Time Traveler's Wife"
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作者 钟晓菁 《海外英语》 2012年第7X期225-226,共2页
In this paper,a review was finished according to a novel-"The Time Traveler's Wife".It use time travel to explore miscommunication and distance in relationships.A lot of knowledge could be obtained from ... In this paper,a review was finished according to a novel-"The Time Traveler's Wife".It use time travel to explore miscommunication and distance in relationships.A lot of knowledge could be obtained from the passage. 展开更多
关键词 BOOK REVIEW The time Traveler’s WIFE Miscommunicat
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Denial of Sartre's Existentialism in The Time Traveler's Wife
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作者 牛丽军 《海外英语》 2016年第17期163-165,共3页
By contrast with Sartre's existentialism,The Time Traveler's Wife depicts another humanistic world.Moreover,such things as meaning,reason,compensation and peace are indispensable in this world.
关键词 the time traveler’s wife sARTRE EXIsTENTIALIsM
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K-S变换及其电网超谐波时频分析应用
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作者 滕召胜 梁成斌 +2 位作者 唐求 张雷鹏 成达 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第6期128-136,共9页
依据FFT→优化窗→IFFT思路,突破线性时频变换的窗函数积分性能桎梏,实现高性能优化窗函数的线性时频变换应用,建立新型时频变换算法——K-S变换.对信号x(t)的FFT频谱向量进行频移处理后,与该频移点下Kaiser优化窗的频谱向量进行Hadamar... 依据FFT→优化窗→IFFT思路,突破线性时频变换的窗函数积分性能桎梏,实现高性能优化窗函数的线性时频变换应用,建立新型时频变换算法——K-S变换.对信号x(t)的FFT频谱向量进行频移处理后,与该频移点下Kaiser优化窗的频谱向量进行Hadamard乘积,再将乘积结果进行FFT逆变换(IFFT),构造出K-S变换复时频矩阵,由此获得x(t)的时间-频率-幅值、时间-频率-相位三维信息;给出逆变换的数学推导与局部性质、线性性质和变分辨率特性;0~150 kHz电网的稳态与时变超谐波信号仿真实验表明,K-S变换的时域、频域分辨能力均优于流行的短时傅里叶变换、S变换,具有优良的变分辨率性能;0~40 kHz超谐波信号的实测证明,基于K-S变换的超谐波电压幅值测量绝对误差均小于0.032 3 V. 展开更多
关键词 K-s变换 时频分析 Kaiser优化窗 变分辨率特性 电网超谐波
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三维各向异性TI介质中的P/S波快速解耦技术及在弹性波逆时偏移中的应用
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作者 张辉 尹国庆 +8 位作者 徐珂 王志民 王海应 梁景瑞 来姝君 左佳卉 鲜成钢 申颍浩 赵杨 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第2期670-683,共14页
随着多分量采集技术的发展,弹性波逆时偏移技术在三维各向异性介质复杂地质构造成像中得到了广泛的应用.然而耦合的P波场和S波场,会在传播过程中产生串扰噪声,降低弹性波逆时偏移的成像精度.为了解决这一问题,本研究针对具有倾斜各向异... 随着多分量采集技术的发展,弹性波逆时偏移技术在三维各向异性介质复杂地质构造成像中得到了广泛的应用.然而耦合的P波场和S波场,会在传播过程中产生串扰噪声,降低弹性波逆时偏移的成像精度.为了解决这一问题,本研究针对具有倾斜各向异性对称轴的三维横向各向同性(Transverse Isotropy,TI)介质,提出了一种矢量弹性波场快速解耦方法,可以有效提高偏移剖面的成像质量.该方法首先通过坐标转换,将观测系统坐标系的垂直轴旋转到TI介质的对称轴方向,在新坐标系下,根据具有垂直对称轴的三维横向各向同性(Vertical Transverse Isotropy,VTI)介质中的分解算子,推导出三维TI介质解耦算子表达式.接着引入一种在空间域快速计算分解波场的方法,来实现空间域矢量P波场和S波场分离,极大地提高了计算效率.最后,通过点积成像条件,将提出的P/S波分解方法引入到三维TI介质弹性波逆时偏移中,得到高精度的PP和PS成像.与以往的波场分解方法相比,本文方法具有数值稳定和计算效率高的特点.数值算例表明,应用上述三维TI分解算子得到的偏移剖面有效压制了噪声,提高了成像质量. 展开更多
关键词 三维各向异性介质 弹性波逆时偏移 矢量P/s波场分解 多分量地震数据
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Mei’s symmetry theorem for time scales nonshifted mechanical systems 被引量:7
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作者 Yi Zhang 《Theoretical & Applied Mechanics Letters》 CSCD 2021年第5期246-251,共6页
We focus on Mei symmetry for time scales nonshifted mechanical systems within Lagrangian framework and its resulting new conserved quantities.Firstly,the dynamic equations of time scales nonshifted holonomic systems a... We focus on Mei symmetry for time scales nonshifted mechanical systems within Lagrangian framework and its resulting new conserved quantities.Firstly,the dynamic equations of time scales nonshifted holonomic systems and time scales nonshifted nonholonomic systems are derived from the generalized Hamilton’s principle.Secondly,the definitions of Mei symmetry on time scales are given and its criterions are deduced.Finally,Mei’s symmetry theorems for time scales nonshifted holonomic conservative systems,time scales nonshifted holonomic nonconservative systems and time scales nonshifted nonholonomic systems are established and proved,and new conserved quantities of above systems are obtained.Results are illustrated with two examples. 展开更多
关键词 Mei’s symmetry theorem Nonholonomic system Nonconservative system time scales Nonshifted calculus of variation
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Clinical implications of doubling time of gastrointestinal submucosal tumors 被引量:3
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作者 Shuko Koizumi Mitsuhiro Kida +6 位作者 Hiroshi Yamauchi Kosuke Okuwaki Tomohisa Iwai Shiro Miyazawa Miyoko Takezawa Hiroshi Imaizumi Wasaburo Koizumi 《World Journal of Gastroenterology》 SCIE CAS 2016年第45期10015-10023,共9页
AIM To evaluate the efficacy of doubling time(DT) of gastrointestinal submucosal tumors(GIST).METHODS From April 1987 through November 2012, a total of 323 patients were given a final histopathological diagnosis of GI... AIM To evaluate the efficacy of doubling time(DT) of gastrointestinal submucosal tumors(GIST).METHODS From April 1987 through November 2012, a total of 323 patients were given a final histopathological diagnosis of GISTs on surgical resection or endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA) in Kitasato University East Hospital or Kitasato University Hospital. We studied 53 of these patients(34 with resected tumors and 19 with unresected tumors) whose tumors could be measured on EUS on at least two successive occasions. The histopathological diagnosis was GIST in 34 patients, leiomyoma in 5, schwannoma in 3, ectopic pancreas in 1, hamartoma in 1, cyst in 1, Brunner's adenoma in 1, and spindle-cell tumor in 7. We retrospectively calculated the DT of GISTs on the basis of the time course of EUS findings to estimate the growth rate of such tumors.RESULTS The DT was 17.2 mo for GIST, as compared with 231.2 mo for leiomyoma, 104.7 mo for schwannoma, 274.9mo for ectopic pancreas, 61.2 mo for hamartoma, 49.0 mo for cyst, and 134.7 mo for Brunner's adenoma. The GISTs were divided into risk classes on the basis of tumor diameters and mitotic figures(Fletcher's classification). The classification was extremely low risk or low risk in 28 patients, intermediate risk in 3, and high risk in 3. DT of GIST according to risk was 24.0 mo for extremely low-risk plus low-risk GIST, 17.1 mo for intermediate-risk GIST, and 3.9 mo for high-risk GIST. DT of GIST was significantly shorter than that of leiomyoma plus schwannoma(P < 0.05), and DT of high-risk GIST was significantly shorter than that of extremely low-risk plus low-risk GIST(P < 0.05).CONCLUSION For GIST, a higher risk grade was associated with a significantly shorter DT. Small SMTs should initially be followed up within 6 mo after detection. 展开更多
关键词 Gastrointestinal submucosal tumor Doubling time submucosal tumor Initial observational duration Endoscopic ultrasonography Endoscopic ultrasonography-guided fine needle aspiration Fletcher’s classification
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Some integral inequalities on time scales 被引量:1
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作者 Adnan Tuna Servet Kutukcu 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第1期23-29,共7页
In this article, we study the reverse HSlder type inequality and HSlder inequality in two dimensional case on time scales. We also obtain many integral inequalities by using HSlder inequalities on time scales which gi... In this article, we study the reverse HSlder type inequality and HSlder inequality in two dimensional case on time scales. We also obtain many integral inequalities by using HSlder inequalities on time scales which give Hardy's inequalities as spacial cases. 展开更多
关键词 integral inequalities Hoelder's inequalities Hardy's inequalities time scales reverse inequality
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Anomalies identification of Earth’s rotation rate time series (2012-2017) for possible correlation with strong earthquakes occurrence 被引量:1
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作者 Fabrizio Ambrosino Lenka Thinová +1 位作者 Milos Briestensky Carlo Sabbarese 《Geodesy and Geodynamics》 2019年第6期455-459,共5页
The analysis of the Earth’s rotation rate time series,from January 1,2012 till December 31,2017,is performed using two different time series analysis methods,both based on signal decomposition joined with forecasting... The analysis of the Earth’s rotation rate time series,from January 1,2012 till December 31,2017,is performed using two different time series analysis methods,both based on signal decomposition joined with forecasting approach.Anomalies in the time series are detected making the comparison between the raw signal and the forecasting one at the 95% confidence interval.The two methods show consistent results and the best is selected according to the evaluation of the prediction uncertainty.Both methods highlight correlations between detected anomalies in the Earth’s rotation rate time series and the world’s earthquakes occurrence with magnitude≥7 and/or number of events≥150 per day,within a time interval of ±10 days from each earthquake event.This study brings an innovation in the analysis of such time series and helps to better understand the extent of this relationship. 展开更多
关键词 Earth’s ROTATION rate time series analysis ANOMALIEs detection EARTHQUAKE
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Retrieval of Electron Return Time from High-order Harmonics Generated in a Mixture of He and Ne Gases 被引量:1
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作者 金成 周效信 赵松峰 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期735-741,共7页
In terms of single-atom induced dipole moment by Lewenstein model, we present the macroscopic high-order harmonic generation from mixed He and Ne gases with different mixture ratios by solving three-dimensional Maxwel... In terms of single-atom induced dipole moment by Lewenstein model, we present the macroscopic high-order harmonic generation from mixed He and Ne gases with different mixture ratios by solving three-dimensional Maxwell's equation of harmonic field. And then we show the validity of mixture formulation by Wagner et al. [Phys. Rev. A 76 (2007) 061403(R)] in macroscopic response level. Finally, using/east squares fitting we retrieve the electron return time of short trajectory by formulation in Kanai et al. [Phys. Rev. Lett. 98 (2007) 153904] when the gas jet is put after the laser focus. 展开更多
关键词 high-order harmonic generation Maxwell's equation Lewenstein model return time
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Classification of Short Time Series in Early Parkinson’s Disease With Deep Learning of Fuzzy Recurrence Plots 被引量:9
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作者 Tuan D.Pham Karin Wardell +1 位作者 Anders Eklund Goran Salerud 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第6期1306-1317,共12页
There are many techniques using sensors and wearable devices for detecting and monitoring patients with Parkinson’s disease(PD).A recent development is the utilization of human interaction with computer keyboards for... There are many techniques using sensors and wearable devices for detecting and monitoring patients with Parkinson’s disease(PD).A recent development is the utilization of human interaction with computer keyboards for analyzing and identifying motor signs in the early stages of the disease.Current designs for classification of time series of computer-key hold durations recorded from healthy control and PD subjects require the time series of length to be considerably long.With an attempt to avoid discomfort to participants in performing long physical tasks for data recording,this paper introduces the use of fuzzy recurrence plots of very short time series as input data for the machine training and classification with long short-term memory(LSTM)neural networks.Being an original approach that is able to both significantly increase the feature dimensions and provides the property of deterministic dynamical systems of very short time series for information processing carried out by an LSTM layer architecture,fuzzy recurrence plots provide promising results and outperform the direct input of the time series for the classification of healthy control and early PD subjects. 展开更多
关键词 Deep learning early Parkinson’s disease(PD) fuzzy recurrence plots long short-term memory(LsTM) neural networks pattern classification short time series
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Using a Grandfather Pendulum Clock to Measure the World’s Shortest Time Interval, the Planck Time (With Zero Knowledge of <i>G</i>) 被引量:1
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2021年第5期1076-1088,共13页
Haug has recently introduced a new theory of unified quantum gravity coined “<em>Collision Space-Time</em>”. From this new and deeper understanding of mass, we can also understand how a grandfather pendu... Haug has recently introduced a new theory of unified quantum gravity coined “<em>Collision Space-Time</em>”. From this new and deeper understanding of mass, we can also understand how a grandfather pendulum clock can be used to measure the world’s shortest time interval, namely the Planck time, indirectly, without any knowledge of G. Therefore, such a clock can also be used to measure the diameter of an indivisible particle indirectly. Further, such a clock can easily measure the Schwarzschild radius of the gravity object and what we will call “Schwarzschild time”. These facts basically prove that the Newton gravitational constant is not needed to find the Planck length or the Planck time;it is also not needed to find the Schwarzschild radius. Unfortunately, there is significant inertia towards new ideas that could significantly alter our perspective on the fundamentals in the current physics establishment. However, this situation is not new in the history of science. Still, the idea that the Planck time can be measured totally independently of any knowledge of Newton’s gravitational constant could be very important for moving forward in physics. Interestingly, an old instrument that today is often thought of as primitive instrument can measure the world’s shortest possible time interval. No atomic clock or optical clock is even close to be able to do this. 展开更多
关键词 Pendulum Clock Planck time Planck Length Planck scale Planck Constant schwarzschild Radius schwarzschild time Collision time Newton’s Gravitational Constant Huygens
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It's Time to Move for School Bus 被引量:1
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作者 Amy Hu 《China's Foreign Trade》 2011年第23期42-43,共2页
Links Following recent fatal accident,school bus checks kick off nationwide in China According to Xinhua news, twenty-one people, including 19 preschoolers and two adults, died and 43 others were injured when a nine-s... Links Following recent fatal accident,school bus checks kick off nationwide in China According to Xinhua news, twenty-one people, including 19 preschoolers and two adults, died and 43 others were injured when a nine-seat school bus illegally carrying 64 people collided head-on with a 展开更多
关键词 sCHOOL It’s time to Move for school Bus
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Diagnostic delay in inflammatory bowel diseases in a German population 被引量:4
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作者 Elisabeth Blüthner Annalena Dehe +11 位作者 Carsten Büning Britta Siegmund Matthias Prager Jochen Maul Alexander Krannich Jan Preiß Bertram Wiedenmann Florian Rieder Raneem Khedraki Frank Tacke Andreas Sturm Anja Schirbel 《World Journal of Gastroenterology》 SCIE CAS 2024年第29期3465-3478,共14页
BACKGROUND Early diagnosis is key to prevent bowel damage in inflammatory bowel disease(IBD).Risk factor analyses linked with delayed diagnosis in European IBD patients are scarce and no data in German IBD patients ex... BACKGROUND Early diagnosis is key to prevent bowel damage in inflammatory bowel disease(IBD).Risk factor analyses linked with delayed diagnosis in European IBD patients are scarce and no data in German IBD patients exists.AIM To identify risk factors leading to prolonged diagnostic time in a German IBD cohort.METHODS Between 2012 and 2022,430 IBD patients from four Berlin hospitals were enrolled in a prospective study and asked to complete a 16-item questionnaire to determine features of the path leading to IBD diagnosis.Total diagnostic time was defined as the time from symptom onset to consulting a physician(patient waiting time)and from first consultation to IBD diagnosis(physician diagnostic time).Univariate and multivariate analyses were performed to identify risk factors for each time period.RESULTS The total diagnostic time was significantly longer in Crohn’s disease(CD)compared to ulcerative colitis(UC)patients(12.0 vs 4.0 mo;P<0.001),mainly due to increased physician diagnostic time(5.5 vs 1.0 mo;P<0.001).In a multivariate analysis,the predominant symptoms diarrhea(P=0.012)and skin lesions(P=0.028)as well as performed gastroscopy(P=0.042)were associated with longer physician diagnostic time in CD patients.In UC,fever was correlated(P=0.020)with shorter physician diagnostic time,while fatigue(P=0.011)and positive family history(P=0.046)were correlated with longer physician diagnostic time.CONCLUSION We demonstrated that CD patients compared to UC are at risk of long diagnostic delay.Future efforts should focus on shortening the diagnostic delay for a better outcome in these patients. 展开更多
关键词 Diagnostic time Diagnostic delay Crohn’s disease Ulcerative colitis GERMANY
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Chaos and Its Impulsive Control in Chua's Oscillator via Time-Delay Feedback 被引量:2
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作者 Yong-Bin Yu Hong-Bin Zhang Zhu-Sheng Kang Xiao-Feng Liao Jue-Bang Yu 《Journal of Electronic Science and Technology of China》 2008年第1期56-60,共5页
A novel framework for chaos and its impul-sive control in Chua's oscillator via time-delay feedback is presented.The exponential stability of impulsive control Chua's oscillator via time-delay feedback is considered... A novel framework for chaos and its impul-sive control in Chua's oscillator via time-delay feedback is presented.The exponential stability of impulsive control Chua's oscillator via time-delay feedback is considered,and some novel conditions are obtained.Then a novel impulsive controller design procedure is proposed.Simulation experiments are provided to demonstrate the feasibility and effectiveness of our method finally. 展开更多
关键词 CHAOs Chua's oscillator EXPONENTIALsTABILITY impulsive control time delay.
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It's time for iPhone 被引量:1
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作者 FOX 《数字通信》 2007年第1期20-21,共2页
估计没有哪个厂商能比苹果的绯闻更多。从2005年6月传出苹果可能、也许、似乎会推出带有通话功能的便携设备到现在,在这一年半的时间里,iPhone就像萦绕在数码爱好者脑海中的美丽剪影,挥之不去,距大家传闻的“2007年1月发布iPhone”的时... 估计没有哪个厂商能比苹果的绯闻更多。从2005年6月传出苹果可能、也许、似乎会推出带有通话功能的便携设备到现在,在这一年半的时间里,iPhone就像萦绕在数码爱好者脑海中的美丽剪影,挥之不去,距大家传闻的“2007年1月发布iPhone”的时间越来越近,各种传闻不断,我们不妨先来看看最近有哪些新闻。 展开更多
关键词 It’s time for iPhone 通话功能 音乐播放器 智能手机 苹果 苹果公司
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R/S method for evaluation of pollutant time series in environmental quality assessment
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作者 Bu Quanmin Bi Jun +1 位作者 Yuan Zengwei Huang Lei 《Water Science and Engineering》 EI CAS 2008年第4期82-88,共7页
The significance of the fluctuation and randomness of the time series of each pollutant in environmental quality assessment is described for the first time in this paper. A comparative study was made of three differen... The significance of the fluctuation and randomness of the time series of each pollutant in environmental quality assessment is described for the first time in this paper. A comparative study was made of three different computing methods: the same starting point method, the striding averaging method, and the stagger phase averaging method. All of them can be used to calculate the Hurst index, which quantifies fluctuation and randomness. This study used real water quality data from Shazhu monitoring station on Taihu Lake in Wuxi, Jiangsu Province. The results show that, of the three methods, the stagger phase averaging method is best for calculating the Hurst index of a pollutant time series from the perspective of statistical regularity. 展开更多
关键词 environmental quality assessment time series fractal dimension R/s statistical method Hurst index
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