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DETERMINE评分与急性心肌梗死PCI术预后关系的分析
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作者 李加乐 刘泽岩 程景林 《中文科技期刊数据库(引文版)医药卫生》 2024年第5期0051-0054,共4页
探讨DETERMINE评分(病理性Q波导联数*2+碎裂QRS波导联数+T波倒置导联数)与急性心肌梗死患者经皮冠状动脉介入(PCI)术后预后的关系。方法 选择2021.1-2022.12在我院住院接受PCI治疗的急性心肌梗死患者206例,根据预后情况分为预后良好组(... 探讨DETERMINE评分(病理性Q波导联数*2+碎裂QRS波导联数+T波倒置导联数)与急性心肌梗死患者经皮冠状动脉介入(PCI)术后预后的关系。方法 选择2021.1-2022.12在我院住院接受PCI治疗的急性心肌梗死患者206例,根据预后情况分为预后良好组(165例)和预后不良组(41例)。比较两组患者的临床资料及DETERMINE评分,采用多因素Logistic回归法分析影响急性心肌梗死PCI术后预后的相关因素;创建受试者工作特征曲线(ROC),分析DETERMINE评分对急性心肌梗死PCI术后预后的预测价值。分析急性心肌梗死PCI术预后不良的影响因素。结果 与预后良好组比较,预后不良组糖尿病史、心律失常史比例及DETERMINE评分、年龄、体重指数、左室射血分数、糖化血红蛋白、低密度脂蛋白胆固醇、总胆固醇水平均显著升高,差异具有统计学意义;二元Logistic回归分析显示DETERMINE评分、心律失常史、体重指数、糖化血红蛋白、低密度脂蛋白胆固醇是冠心病患者PCI手术预后不良的独立危险因素(OR=1.443~15.658,P<0.05)。结论 DETERMINE评分与冠心病PCI术预后相关,需引起临床关注。 展开更多
关键词 determine评分 急性心肌梗死 PCI术后 预后
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The Role of Electrocardiogram DETERMINE Score in Prediction of Coronary Artery Disease Severity
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作者 Ismail N. El-Sokkary Essam Ahmed Khalil +5 位作者 Mohammed Wael Badawi Ibrahim K. Gamil Shousha Abdalla A. Elsebaey Mohamed Kamal Rehan Mahmoud Ibrahim Elshamy Yasser Ahmed Sadek 《World Journal of Cardiovascular Diseases》 CAS 2024年第9期567-580,共14页
Background: A major cause of mortality and disability on a global scale is myocardial infarction (MI). These days, the most reliable way to detect and measure MI is via cardiovascular magnetic resonance imaging (CMR).... Background: A major cause of mortality and disability on a global scale is myocardial infarction (MI). These days, the most reliable way to detect and measure MI is via cardiovascular magnetic resonance imaging (CMR). Aims and Objectives: To evaluate the effectiveness of the Electrocardiogram DETERMINE Score in predicting the severity of coronary artery disease (CAD) in patients who have experienced an Acute Myocardial Infarction (AMI) & to assess improvements in left ventricular function at 6 months following coronary artery bypass grafting (CABG). Subjects and Methods: This Observational cohort study was done at the Cardiology and Radiology department and cardiac surgery department, Al-Azhar university hospitals and Helwan University hospital. The study involved 700 cases who patients diagnosed with Acute Myocardial Infarction and fulfilled specific criteria for selection. Result: There was highly statistically significant relation between Myocardial infarction size and ECG Marker Score as mean infarct size elevated When the number of ECG markers increased. There was a highly statistically significant relation between myocardial infarct segments, myocardial infarction size and improvement of cardiac function 6 months post-CABG. Conclusion: The study found that larger myocardial infarctions corresponded with higher DETERMINE Scores. It concluded that an ECG-based score better estimates infarct size than LVEF alone. Additionally, there was a significant statistical correlation between the size and segmentation of myocardial infarction and better cardiac function six months after CABG. 展开更多
关键词 Electrocardiogram determine Score Coronary Artery Disease OUTCOME Acute Myocardial Infarction Coronary Artery Bypass Grafting
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Cryo-EM combined with image deconvolution to determine ZIF-8 crystal structure
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作者 吴抗 杨柏松 +3 位作者 薛文华 孙大鹏 葛炳辉 王玉梅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期44-49,共6页
Metal–organic frameworks(MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2]It is challenging to visualize MOFs with transmissi... Metal–organic frameworks(MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2]It is challenging to visualize MOFs with transmission electron microscopy(TEM) due to their inherent instability under electron beam irradiation. Here, we employ cryo-electron microscopy(cryoEM) to capture images of MOF ZIF-8, revealing inverted-space structural information at a resolution of up to about 1.7A and enhancing its critical electron dose to around 20 e^(-)/A^(2). In addition, it is confirmed by electron-beam irradiation experiments that the high voltage could effectively mitigate the radiolysis, and the structure of ZIF-8 is more stable along the [100] direction under electron beam irradiation. Meanwhile, since the high-resolution electron microscope images are modulated by contrast transfer function(CTF) and it is difficult to determine the positions corresponding to the atomic columns directly from the images. We employ image deconvolution to eliminate the impact of CTF and obtain the structural images of ZIF-8. As a result, the heavy atom Zn and the organic imidazole ring within the organic framework can be distinguished from structural images. 展开更多
关键词 cryo-electron microscopy(cryo-EM) ZIF-8 image deconvolution crystal structure determination
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What determines irrigation efficiency when farmers face extreme weather events? A field survey of the major wheat producing regions in China 被引量:5
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作者 SONG Chun-xiao Les Oxley MA Heng-yun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第8期1888-1899,共12页
Water availability is a major constraint on grain production in China, therefore, improving irrigation efficiency is particularly important when agriculture faces extreme weather events. This paper first calculates ir... Water availability is a major constraint on grain production in China, therefore, improving irrigation efficiency is particularly important when agriculture faces extreme weather events. This paper first calculates irrigation efficiency with a translog stochastic frontier production function and then investigates what happens when extreme weather events occur via a Tobit model. The estimated results reveal several important features of irrigation practices: i) irrigation efficiency is lower when extreme weather events occur; ii) large variations in irrigation efficiency occur across irrigation facilities; iii) the farm plots exhibit an extreme distribution across efficiency levels; and iv) water-saving techniques, technology adoption, and the maintenance of farmers’ economic resilience are major determinants of irrigation efficiency. Based on these results we propose the following recommendations: i) farmers should balance crop yield and water use; undertake relevant training programs and adopt water-saving techniques; ii) local governments and researchers should help farmers to find the optimal level of irrigation water use based on their own circumstances and provide better water-saving techniques and training programs rather than simply encouraging farmers to invest in irrigation facilities in the most extreme weather years; and iii) the income level of farm households should be increased so as to improve their resilience to natural disasters. 展开更多
关键词 irrigation efficiency determinants irrigation facilities water-saving techniques extreme weather events
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A Mathematical Calculation Model Using Biomarkers to Quantitatively Determine the Relative Source Proportion of Mixed Oils 被引量:3
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作者 CHEN Jianping DENG Chunping +1 位作者 SONG Fuqing ZHANG Dajiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第5期817-826,共10页
It is difficult to identify the source(s) of mixed oils from multiple source rocks, and in particular the relative contribution of each source rock. Artificial mixing experiments using typical crude oils and ratios ... It is difficult to identify the source(s) of mixed oils from multiple source rocks, and in particular the relative contribution of each source rock. Artificial mixing experiments using typical crude oils and ratios of different biomarkers show that the relative contribution changes are non-linear when two oils with different concentrations of biomarkers mix with each other. This may result in an incorrect conclusion if ratios of biomarkers and a simple binary linear equation are used to calculate the contribution proportion of each end-member to the mixed oil. The changes of biomarker ratios with the mixing proportion of end-member oils in the trinal mixing model are more complex than in the binary mixing model. When four or more oils mix, the contribution proportion of each end-member oil to the mixed oil cannot be calculated using biomarker ratios and a simple formula. Artificial mixing experiments on typical oils reveal that the absolute concentrations of biomarkers in the mixed oil cause a linear change with mixing proportion of each end-member. Mathematical inferences verify such linear changes. Some of the mathematical calculation methods using the absolute concentrations or ratios of biomarkers to quantitatively determine the proportion of each end-member in the mixed oils are deduced from the results of artificial experiments and by theoretical inference. Ratio of two biomarker compounds changes as a hyperbola with the mixing proportion in the binary mixing model, as a hyperboloid in the trinal mixing model, and as a hypersurface when mixing more than three end- members. The mixing proportion of each end-member can be quantitatively determined with these mathematical models, using the absolute concentrations and the ratios of biomarkers. The mathematical calculation model is more economical, convenient, accurate and reliable than conventional artificial mixing methods. 展开更多
关键词 mixed oil BIOMARKER oil source correlation quantitative determination mathematical model
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A New Parameter of Cleanability to Determine the Clean Potential of Coal Resources 被引量:2
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作者 TANG Yuegang YANG Shuting WANG Xiaoshuai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2338-2339,共2页
Objective This work is based on analysis on large numbers of coal data such as the latest national coal potential evaluation data and previous data published by REN Deyi, TANG Xiuyi and LU Xukun, and the evaluation m... Objective This work is based on analysis on large numbers of coal data such as the latest national coal potential evaluation data and previous data published by REN Deyi, TANG Xiuyi and LU Xukun, and the evaluation methods of clean potential of coal resources proposed by predecessors. It is found that previous method rank coal is only in accordance with raw coal or washed coal, which fail to take full account of the changes in elements before and after coal washing. Some elements can be removed by washing or other methods, and others may be even enriched after the coal is washed. For this reason, this work defined a new parameter of cleanability and developed its calculation formula to determine the clean potential of coal resources. Cleanability is a comprehensive indicator based on the removal rate of each indicator harmful element in coal. The clean potential of coal is proportional to the value of cleanability. The higher the cleanability value is, the better the clean potential is, and vice versa. 展开更多
关键词 Cleanability to determine the Clean Potential of Coal
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Comparing and evaluating the nationally determined contributions of the top six emitters under the Paris Agreement goals 被引量:1
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作者 Xunzhang Pan Jie Tao Hailin Wang 《Chinese Journal of Population,Resources and Environment》 2018年第3期211-219,共9页
Comparing and evaluating the Nationally Determined Contribution(NDC) is an important element in global stocktake in the post-Paris climate negotiations, aimed at closing the emissions gap with the Paris Agreement goal... Comparing and evaluating the Nationally Determined Contribution(NDC) is an important element in global stocktake in the post-Paris climate negotiations, aimed at closing the emissions gap with the Paris Agreement goals. To date, however, there has still been no explicit guideline or method. By applying emissions allowance allocated by 16 schemes as benchmarks, this paper tries to compare and evaluate the NDCs of the top six emitters, which jointly account for about 70% of the world's CO_2 emissions. Results show that the four developed countries' NDCs lack ambition with respect to most allocations under 2℃ and all under 1.5℃, indicating they need to substantially ratchet up their NDCs and lead elevating mitigation. Evaluating cumulative emissions is more likely to clarify the ambition and fairness of China's NDC. If considering cumulative emissions, China's NDC is aligned with the median of cumulative allowances under 2℃ and within the 1.5℃ range. The Paris Agreement invited the Parties to communicate the mid-century low emissions strategies. This paper also tries to explore the mid-century mitigation in the perspective of allocations, which might provide decision-makers with some useful information when envisaging the post-NDC mitigation. 展开更多
关键词 PARIS AGREEMENT nationally determined contribution top SIX EMITTERS emissions ALLOWANCE ALLOCATIONS midcentury mitigation
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Climate Warming Mitigation from Nationally Determined Contributions 被引量:2
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作者 Bo FU Jingyi LI +7 位作者 Thomas GASSER Philippe CIAIS Shilong PIAO Shu TAO Guofeng SHEN Yuqin LAI Luchao HAN Bengang LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第8期1217-1228,共12页
Individual countries are requested to submit nationally determined contributions(NDCs)to alleviate global warming in the Paris Agreement.However,the global climate effects and regional contributions are not explicitly... Individual countries are requested to submit nationally determined contributions(NDCs)to alleviate global warming in the Paris Agreement.However,the global climate effects and regional contributions are not explicitly considered in the countries’decision-making process.In this study,we evaluate the global temperature slowdown of the NDC scenario(ΔT=0.6°C)and attribute the global temperature slowdown to certain regions of the world with a compact earth system model.Considering reductions in CO_(2),CH_(4),N_(2)O,BC,and SO_(2),the R5OECD(the Organization for Economic Co-operation and Development in 1990)and R5ASIA(Asian countries)are the top two contributors to global warming mitigation,accounting for 39.3%and 36.8%,respectively.R5LAM(Latin America and the Caribbean)and R5MAF(the Middle East and Africa)followed behind,with contributions of 11.5%and 8.9%,respectively.The remaining 3.5%is attributed to R5REF(the Reforming Economies).Carbon Dioxide emission reduction is the decisive factor of regional contributions,but not the only one.Other greenhouse gases are also important,especially for R5MAF.The contribution of short-lived aerosols is small but significant,notably SO_(2)reduction in R5ASIA.We argue that additional species beyond CO_(2)need to be considered,including short-lived pollutants,when planning a route to mitigate climate change.It needs to be emphasized that there is still a gap to achieve the Paris Agreement 2-degree target with current NDC efforts,let alone the ambitious 1.5-degree target.All countries need to pursue stricter reduction policies for a more sustainable world. 展开更多
关键词 climate mitigation nationally determined contributions ATTRIBUTION regional contribution integrated assessment models
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Diethylstilbestrol in Fish Tissue Determined Through Subcritical Fluid Extraction and with GC-MS 被引量:1
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作者 QIAO Qinghui SHI Nianrong +3 位作者 FENG Xiaomei LU Jie HAN Yuqian XUE Changhu 《Journal of Ocean University of China》 SCIE CAS 2016年第3期489-494,共6页
As the key point in sex hormone analysis, sample pre-treatment technology has attracted scientists' attention all over the world, and the development trend of sample preparation forwarded to faster and more effici... As the key point in sex hormone analysis, sample pre-treatment technology has attracted scientists' attention all over the world, and the development trend of sample preparation forwarded to faster and more efficient technologies. Taking economic and environmental concerns into account, subcritical fluid extraction as a faster and more efficient method has stood out as a sample pre-treatment technology. This new extraction technology can overcome the shortcomings of supercritical fluid and achieve higher extraction efficiency at relatively low pressures and temperatures. In this experiment, a simple, sensitive and efficient method has been developed for the determination of diethylstilbestrol(DES) in fish tissue using subcritical 1,1,1,2-tetrafluoroethane(R134a) extraction in combination with gas chromatography-mass spectrometry(GC-MS). After extraction, freezing-lipid filtration was utilized to remove fatty co-extract. Further purification steps were performed with C_(18) and NH_2 solid phase extraction(SPE). Finally, the analyte was derived by heptafluorobutyric anhydride(HFBA), followed by GC-MS analysis. Response surface methodology(RSM) was employed to optimizing the extraction condition, and the optimized was as follows: extraction pressure, 4.3 MPa; extraction temperature, 26℃; amount of co-solvent volume, 4.7 m L. Under this condition, at a spiked level of 1, 5, 10 μg kg^(-1), the mean recovery of DES was more than 90% with relative standard deviations(RSDs) less than 10%. Finally, the developed method has been successfully used to analyzing the real samples. 展开更多
关键词 subcritical R134a extraction DIETHYLSTILBESTROL GC-MS determination fish tissue
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Angle Dependence Analysis Method to Determine SNRArc Applied to GNSSMRSea Level Retrieval 被引量:6
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作者 Xiaolei WANG Xiufeng HE +2 位作者 Qin ZHANG Mingfeng SONG Zijin NIU 《Journal of Geodesy and Geoinformation Science》 2021年第2期14-26,共13页
The Global Navigation Satellite Systems(GNSS)broadcast radio signals are continuously at two or more frequencies in the L-band,and the multipath signals from sea surface recorded by off-the-shelf geodetic receivers ha... The Global Navigation Satellite Systems(GNSS)broadcast radio signals are continuously at two or more frequencies in the L-band,and the multipath signals from sea surface recorded by off-the-shelf geodetic receivers have been demonstrated they can be used to estimate sea level,using a technology called GNSS multipath reflectometry(GNSS-MR).Before proceeding to estimate reflection parameters,the azimuth range and elevation angle range are needed to be defined,as only with suitable azimuths and elevation angles the sensing zones can be guaranteed on water.So,this study presents an angle dependence analysis method to jointly select the azimuth range and elevation angle range based on wavelet analysis which can describe the nonstationary power of different sinusoidal oscillations changed with elevation angle.The key of this method is to use one grid model to screen the spectrum power of multipath oscillation on different elevation angles and azimuths in this work.Then the elevation angles and the azimuths can be determined by searching grids with greater power.The GPS and GLONASS data of two MultiGNSS Experiment(MGEX)stations named BRST and MAYG was analyzed and used to retrieve.Firstly,the angle dependence analysis was carried out to determine the elevation range and azimuth range.Secondly,the sea levels were retrieved from individual signals.Finally,the retrievals of individual signals are combined to form a 10-min sea level retrieval series.The RMSEs of the combined retrievals are both less than 15 cm.The results show the effectiveness of the selection of angle range based on the angle dependence analysis method. 展开更多
关键词 GNSS-MR sea level azimuth determination elevation angle determination multi-GNSS combination
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DISCUSSION ON SOME FFT PROBLEMS TO DETERMINE THE GEOID
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作者 Essam Ghanem LI Jiancheng 《Geo-Spatial Information Science》 2000年第2期53-57,共5页
The aim of this investigation is to study some FFT problems related to the application of FFT to gravity field convolution integrals.And the others,such as the effect of spectral leakage,edge effects,cyclic convolutio... The aim of this investigation is to study some FFT problems related to the application of FFT to gravity field convolution integrals.And the others,such as the effect of spectral leakage,edge effects,cyclic convolution and effect of padding,are also discussed.A numerical test for these problems is made.A large area of Western China selected for the test is located between 30°N~36°N and 96°E~102°E and includes 1 858 gravity observations on land.The results show that the removal of the bias in the residual gravity anomalies is important to avoid spectral leakage.One hundred percent zero padding is highly recommended for further research of the geoid to remove cyclic convolution errors and edge effects.1_D FFT is recommended for precise local geoid determination because it does not use kernel approximation. 展开更多
关键词 fast FOURIER TRANSFORMATION (FFT) GEOID determination
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DETERMINE ON INITIAL DIMENSIONAL STABILITY OF CHEMICAL MODIFIED WOOD
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作者 Banks W. B. Jones G.L. 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1991年第1期70-78,共9页
Strain development along radial direction was continuously determined by D-200 Linear Variable Differential Transformers (L.V.D.T). When a wood specimen was put into water and begin to swell from absolute dry moisture... Strain development along radial direction was continuously determined by D-200 Linear Variable Differential Transformers (L.V.D.T). When a wood specimen was put into water and begin to swell from absolute dry moisture content to the maximum. Experiment results show that the differences of swelling with soaking time between untreated and treated wood specimens due to uptaking water. It would also give an indication to the effectiveness of various chemicals on the dimensional stability of modified wood. ASE of modified wood samples with SA-EP, EP and SA were found to be better than MA-AGE. SA-EP had got the best effetivencss on dimensional stability in reducing the swelling. 展开更多
关键词 SWELLING determinATION Modified wood
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Numerical Experiment of Combined Infrared and Ultraviolet Radiation Remote Sensing to Determine the Profile and Total Content of Atmospheric Ozone 被引量:1
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作者 程明虎 石广玉 周秀骥 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第3期305-319,共15页
A new remote sensing method is described to determine the vertical distribution and total content of atmospheric ozone. The method combines surface infrared, satellite infrared and ultraviolet channels. The width of t... A new remote sensing method is described to determine the vertical distribution and total content of atmospheric ozone. The method combines surface infrared, satellite infrared and ultraviolet channels. The width of the infrared channels is 0.01 cm-1, less than Lorentz half-width at the earth's surface, rather than the present width, because these channels can obtain information about variations in the ozone profile below the profile main-peak. The numerical experiments show that the method has a satisfactory precision in determining total ozone content, just about I percent error, and vertical distribution from the earth to 65 km space. In addition, some semi-analysis functions lor calculating backscattered ultraviolet and a relaxation equation are described in this paper. 展开更多
关键词 FIGURE SHOW Numerical Experiment of Combined Infrared and Ultraviolet Radiation Remote Sensing to determine the Profile and Total Content of Atmospheric Ozone
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Application of ^(241)Am EDXRF to Determine Heavy Rare Earths in RE Separation Processes by Solvent Extraction
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作者 贾江涛 马小桃 +2 位作者 严纯华 廖春生 李标国 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第4期68-72,共5页
A fast EDXRF analysis by using radioisotope, 241 Am as an exciting source and high purity Ge as a planar detector in heavy rare earth separation processes by solvent extraction has been investigated Applying th... A fast EDXRF analysis by using radioisotope, 241 Am as an exciting source and high purity Ge as a planar detector in heavy rare earth separation processes by solvent extraction has been investigated Applying the method, heavy rare earth chloride aqueous samples in Er/Tm and Y/Er separation processes were off line analyzed The results show that the method can be used for a wide range of rare earth concentration(0 1 g/L~300 g/L) with high accuracy 展开更多
关键词 Rare earths EDXRF Solvent extraction HRE determination
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What determines walking of older people in their neighborhood?
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作者 Marijke Hopman-Rock Sanne I de Vries +1 位作者 Ingrid Bakker Wil TM Ooijendijk 《Open Journal of Preventive Medicine》 2012年第3期279-286,共8页
Based on literature review and five focus groups, a model was analyzed describing individual, social environmental and physical environmental (perceived) determinants of walking by older people. Aim was to test whethe... Based on literature review and five focus groups, a model was analyzed describing individual, social environmental and physical environmental (perceived) determinants of walking by older people. Aim was to test whether these determinants were significantly associated with the duration of walking by older people (N = 567, 50 - 80 years) in a middle-sized Dutch town. Walking time was best predicted by attitude towards walking (partial correlation in model (partial r) 0.18;p r 0.12, p r 0.21 p r - 0.14, p r 0.28 p < 0.01). The model explained 20% of the total variance in walking time. Conclusion is that individual and social determinants predicted the most variance in walking time and that perceived environmental determinants played only a minor role. Health promotion actions may benefit from these insights. 展开更多
关键词 OLDER ADULTS Physical Activity Environment Health determinants
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A Fast-Speed Pulse Detector Based on N-Type Si-Schottky Diode via Tuning Circuit
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作者 Ling Wang Xiao-Hong Tang Fei Xiao Shang-Yun Wu 《Journal of Electronic Science and Technology》 CAS 2010年第3期257-261,共5页
A fast-speed pulse detector based on n-type Si-Sehottky diode mounted in the waveguide is investigated. The relation of the fast-speed pulse detector between response time and 3 dB bandwidth is analyzed. By adopting t... A fast-speed pulse detector based on n-type Si-Sehottky diode mounted in the waveguide is investigated. The relation of the fast-speed pulse detector between response time and 3 dB bandwidth is analyzed. By adopting the tunable circuit, the matched bandwidth is achieved as wide as possible. Experi- mental results show that the pulse response time of the detector is less than 150 ps within random carrier signal 500 MHz bandwidth range between 35 GHz to 39 GHz via tuning circuit. The detector is very easy to operate because it does not need bias current or synch-pulse source. 展开更多
关键词 DETECTOR fast-speed pulse millimeter- wave response time Si-Schottky diode.
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determine用法种种
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作者 赵常玲 《英语辅导(高中年级)》 2002年第1期7-7,共1页
determine v.“决心、决定”。
关键词 determine 用法 高中 英语
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Computational Intelligence Determines Effective Rationality
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作者 Edward P.K.Tsang 《International Journal of Automation and computing》 EI 2008年第1期63-66,共4页
Rationality is a fundamental concept in economics. Most researchers will accept that human beings are not fully rational. Herbert Simon suggested that we are "bounded rational". However, it is very difficult to quan... Rationality is a fundamental concept in economics. Most researchers will accept that human beings are not fully rational. Herbert Simon suggested that we are "bounded rational". However, it is very difficult to quantify "bounded rationality", and therefore it is difficult to pinpoint its impact to all those economic theories that depend on the assumption of full rationality. Ariel Rubinstein proposed to model bounded rationality by explicitly specifying the decision makers' decision-making procedures. This paper takes a computational point of view to Rubinstein's approach. From a computational point of view, decision procedures can be encoded in algorithms and heuristics. We argue that, everything else being equal, the effective rationality of an agent is determined by its computational power - we refer to this as the computational intelligence determines effective rationality (CIDER) theory. This is not an attempt to propose a unifying definition of bounded rationality. It is merely a proposal of a computational point of view of bounded rationality. This way of interpreting bounded rationality enables us to (computationally) reason about economic systems when the full rationality assumption is relaxed. 展开更多
关键词 RATIONALITY bounded rationality computational intelligence ECONOMICS computational intelligence determines effective rationality (CIDER) theory.
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KT Boundary Chromites Determined to be Terrestrial:Cr Isotopic Evidence for Excavation and Ejection of Mafic/Ultramafic Rocks by the KT Boundary Impact 被引量:1
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作者 Peter OLDS Mathew E.SANBORN +1 位作者 Tim TEAGUE YIN Qingzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期26-27,共2页
Evidence for a mantle and/or basaltic component in KT boundary distal ejecta is apparently inconsistent with ejection from Chicxulub Crater since it is located on;5km thick continental crust(De Paolo et al.,1983;Mont... Evidence for a mantle and/or basaltic component in KT boundary distal ejecta is apparently inconsistent with ejection from Chicxulub Crater since it is located on;5km thick continental crust(De Paolo et al.,1983;Montanari et al.,1983;Hildebrand and Boynton,1988,1990).Evidence for mafic/ultramafic target rocks was reinforced by discovery of chromites,some with shock planar deformation features(PDF),in impact layer samples from sites in southern Colorado and eastern Wyoming(Bohor et al.,1990).However,until now it was unclear whether the chromites originated with an impactor or with terrestrial target rocks.To this end,high-precision 54Cr/52Cr isotope ratios were measured on KT boundary chromites along with known terrestrial chromites.We find a terrestrial 54Cr/52Cr ratio in KT boundary chromites from impact layer samples collected at the above sites over the last several years(Fig.1).Ejected terrestrial chromites suggest the impact sampled terrestrial mafic and/or ultramafic target rocks not known to exist in the Chicxulub target area. 展开更多
关键词 KT Boundary Chromites determined to be Terrestrial Cr Isotopic Evidence for Excavation and Ejection of Mafic/Ultramafic Rocks by the KT Boundary Impact
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再论DETERMINER
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作者 国文 《昌潍师专学报》 1998年第3期56-57,共2页
Determiner 是国外语言学家提出的话法术语,在各种语法著作中当做词类介绍,国内语言学界将其译为"限定词"。作者在分析了其来源、构成、分类及作用等后,提出 Determiner 不应被视作"词",而应看作是词组成分,可译为&... Determiner 是国外语言学家提出的话法术语,在各种语法著作中当做词类介绍,国内语言学界将其译为"限定词"。作者在分析了其来源、构成、分类及作用等后,提出 Determiner 不应被视作"词",而应看作是词组成分,可译为"限定语"。 展开更多
关键词 determineR 限定词 词组成分 限定语
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