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Proximal-distal motor unit number estimationdynamic changes in patients with amyotrophic lateral sclerosis A one-year follow-up
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作者 Sartucci Ferdinando Moscato Gianluca +5 位作者 Rossi Chiara Caleo Matteo Bocci Tommaso Murri Luigi Giannini Fabio Rossi Alessandro 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第8期597-601,共5页
BACKGROUND:Amyotrophic lateral sclerosis (ALS) is the most common of all the motor neuron diseases and the absence of a biologic marker has made both diagnosis and tracking evolution of the disease difficult, Elect... BACKGROUND:Amyotrophic lateral sclerosis (ALS) is the most common of all the motor neuron diseases and the absence of a biologic marker has made both diagnosis and tracking evolution of the disease difficult, Electrodiagnostic tests play a fundamental role in quantifying pathological changes in the motor unit pool.OBJECTIVE:We assessed distal-proximal Motor Unit (MU) loss and changes using the method of motor unit number estimation (MUNE).DESIGN, TIME AND SETTING:A case-control study was performed at the Department of Neuroscience, Pisa University Medical School, Italy from December 1999 to November 2009. PARTICIPANTS:A total of 50 ALS patients were recruited, 30 males:mean age (59.6 ± 13.3) years; 20 females:mean age (63.9 ± 11.7) years; range (30-82) years; all patients had probable or definite ALS. Thirty healthy volunteers were recruited from department staffs, including 20 males and 10 females; mean age (57.7 ± 13.8) years served as controls.METHODS:MUNE was performed for both the biceps brachii and abductor digiti minimi muscles of the same side. The technique used relayed substantially on manual incremental stimulation of the motor nerve, known as the McComas technique (50 ms sweep duration, a gain of 2 mV/Div for M wave, 0.5 mV/Div for each step; filters 10-20 kHz).MAIN OUTCOME MEASURES:MUNE results were measured.RESULTS:Functioning MU numbers, measured by MUNE, decreased in the biceps brachii and abductor digiti minimi muscles over the entire one-year follow-up period (one assessment every three months) compared with baseline determination, the rate of MU decrease was similar in both muscles, but steeper distally.CONCLUSION:MUNE is a feasible method for ALS patients both proximally and distally to track changes over time in muscle MUs during the disease's evolution. 展开更多
关键词 motor unit number estimation amyotrophic lateral sclerosis motor neuron disease time changes DENERVATION REINNERVATION
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牛津英语1A Unit 2 Numbers第三课时教学设计
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作者 王永杰 《现代教育科学》 2017年第S1期28-30,共3页
一、教学背景分析教材简析:本课是上海教育出版社牛津小学英语教材1A《Unit2 Numbers》第三课时Let’s learn这一部分内容。本节课的教学内容是“1-6”六个数词的三会学习并与相应的名词复数一起呈现。教学内容贴近学生的生活和学习,有... 一、教学背景分析教材简析:本课是上海教育出版社牛津小学英语教材1A《Unit2 Numbers》第三课时Let’s learn这一部分内容。本节课的教学内容是“1-6”六个数词的三会学习并与相应的名词复数一起呈现。教学内容贴近学生的生活和学习,有利于培养他们在真实的生活场景中灵活运用所学的英语,解决实际问题的能力。学情分析:本课授课对象是刚踏入校门的一年级小学生。他们年龄小,活泼好动,有意注意的时间短。 展开更多
关键词 认读能力 Unit 2 numbers 学习英语 学生会
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Understanding the Variability of Z-R Relationships Caused by Natural Variations in Raindrop Size Distributions(DSD):Implication of Drop Size and Number 被引量:1
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作者 Abe D.Ochou Eric-Pascal Zahiri +1 位作者 Bakary Bamba Manlandon Koffi 《Atmospheric and Climate Sciences》 2011年第3期147-164,共18页
In the issue of rainfall estimation by radar through the necessary relationship between radar reflectivity Z and rain rate R (Z-R), the main limitation is attributed to the variability of this relationship. Indeed, se... In the issue of rainfall estimation by radar through the necessary relationship between radar reflectivity Z and rain rate R (Z-R), the main limitation is attributed to the variability of this relationship. Indeed, several pre-vious studies have shown the great variability of this relationship in space and time, from a rainfall event to another and even within a single rainfall event. Recent studies have shown that the variability of raindrop size distributions and thereby Z-R relationships is therefore, more the result of complex dynamic, thermody-namic and microphysical processes within rainfall systems than a convective/stratiform classification of the ground rainfall signature. The raindrop number and size at ground being the resultant of various processes mentioned above, a suitable approach would be to analyze their variability in relation to that of Z-R relation-ship. In this study, we investigated the total raindrop concentration number NT and the median volume di-ameter D0 used in numerous studies, and have shown that the combination of these two ‘observed’ parame-ters appears to be an interesting approach to better understand the variability of the Z-R relationships in the rainfall events, without assuming a certain analytical raindrop size distribution model (exponential, gamma, or log-normal). The present study is based on the analysis of disdrometer data collected at different seasons and places in Africa, and aims to show the degree of the raindrop size and number implication in regard to the Z-R relationships variability. 展开更多
关键词 Raindrop Size Distribution Radar Reflectivity Factor Rain Rate Median Volume Diameter Total number of Drops Per Unit Volume Z-R Relationship Convective Rain Stratiform Rain Squall Lines THUNDERSTORM
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Investigating the Synthesis of RBF Networks 被引量:2
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作者 V. David Sanchez A.(German Aerospace Research Establishment, DLR OberpfaffenhofenInstitute for Robottes and System DynamicsD-82230 Wessling, Germany) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第3期25-29,共5页
The approximation capability of RBF networks is investigated using a test function and a fixed finite number of training data. The test function used allows to confirm the recently introducedconcept of second derivati... The approximation capability of RBF networks is investigated using a test function and a fixed finite number of training data. The test function used allows to confirm the recently introducedconcept of second derivative dependent placement of RBF centers. Different Gaussian RBF networksare trained varying the width and the number of centers (number of hidden units). The dependenceof the approximation error on these network parameters is studied experimentally. 展开更多
关键词 Approximation error Function approximation Neural network synthesis number of hidden units Radial basis functions.
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Experimental Study on Performance of Supercritical CO_2 Heat Exchanger with Four Different Inner Tubes
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作者 吕静 曹科 +2 位作者 石冬冬 吕锋 马逸平 《Journal of Donghua University(English Edition)》 EI CAS 2016年第1期138-143,共6页
The experiment was conducted to investigate the heat transfer performance of supercritical CO_2 in a casing heat exchanger by comparing their heat transfer,entropy production unit number,non-dimensional entropy produc... The experiment was conducted to investigate the heat transfer performance of supercritical CO_2 in a casing heat exchanger by comparing their heat transfer,entropy production unit number,non-dimensional entropy production rate and field synergy factor.The results show that both heat transfer and entropy production unit number in four tubes decrease with water temperature increasing.Heat transfer and entropy production unit number in multiple tubes( i. e.,triple straight tube and double helix tube) is higher than their single counterparts; the non-dimensional entropy production rate increases with water temperature. Non-dimensional entropy production rate of triple straight tube and double helix tube is far below the single tube. Field synergy factor of double helix tube is much higher than that of the triple straight tube under the same condition. Further experiment was carried out in double helix tube,under various CO_2 pressure and inlet water temperature,the results are analyzed and reported in this paper. 展开更多
关键词 supercritical CO2 casing tube heat exchanger entropy production unit number non-dimensional entropy production rate field synergy factor
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Optimization of Band Gap of 1D Elastic Metamaterial Under Impact Load by Regulating Stiffness
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作者 Tong Li Xianlong Jin +1 位作者 Yongqiang Li Peizhong Yang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2024年第1期148-154,共7页
Designing materials that mitigate impacts effectively are crucial for protecting people and structures.Here,a single-resonator metamaterial with negative mass characteristics is proposed for impact mitigation,and nume... Designing materials that mitigate impacts effectively are crucial for protecting people and structures.Here,a single-resonator metamaterial with negative mass characteristics is proposed for impact mitigation,and numerical analysis of wave propagation shows explicitly how the spring stiffness and number of unit cells influence that mitigation.The results show clearly that a metamaterial with differing microstructural stiffness is better at mitigating the effect of a shock wave than one with a unique stiffness.Also,there is a critical number of unit cells beyond which the shock wave is not attenuated further,but the fabrication complexity increases.In the 40 groups of microstructural regions in this example,the attenuation effect no longer increases when there are more than 35 groups.This work offers guidance for microstructure designs in metamaterials and provides new ideas for using metamaterials to mitigate shock waves. 展开更多
关键词 Elastic metamaterials Wave attenuation STIFFNESS number of unit cells
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Hydraulics of crest spillway with large unit discharge and low Froude number 被引量:2
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作者 吴建华 李程纯子 +2 位作者 马飞 李同春 吴伟伟 《Journal of Hydrodynamics》 SCIE EI CSCD 2015年第2期242-247,共6页
With respect to the crest spillway with large unit discharge and low Froude number, the hydraulics of the slit-type energy dissipater at the outlet should be noticed due to the complicated flow regimes. In the present... With respect to the crest spillway with large unit discharge and low Froude number, the hydraulics of the slit-type energy dissipater at the outlet should be noticed due to the complicated flow regimes. In the present paper, some issues about hydraulic characteristics were experimentally investigated by means of five slit-type outlets and four tetrahedrons, including the flow choking, impact to river banks and jet trajectory. The main findings are as follows. The critical Froude number for the flow choking decreases with increasing outlet width of the slit-type energy dissipater. If the flow Froude number is expressed by the parameters just before this energy dissipater, the tetrahedron placed inside the side wall of the outlet could efficiently avoid the flow impact to the river bank of same side, and compared with the jet trajectory of the slit-type energy dissipater, the outlet with tetrahedron has different trajectory trend, i.e., the distance of the jet trajectory decreases with the increase of the water head due to special form of the outlet tetrahedron. 展开更多
关键词 large unit discharge low Froude number flow choking impact to river bank jet trajectory
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Heat transfer effectiveness characteristics maps for additively manufactured TPMS compact heat exchangers 被引量:1
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作者 Moza Alteneiji Mohamed I.Hassan Ali +1 位作者 Kamran A.Khan Rashid K.Abu Al-Rub 《Energy Storage and Saving》 2022年第3期153-161,共9页
Increased power density in modern miniaturized electronics caused difficulty in keeping electronic performance effective.This challenge leads to the search for high-performance compact heat exchanger as one of the the... Increased power density in modern miniaturized electronics caused difficulty in keeping electronic performance effective.This challenge leads to the search for high-performance compact heat exchanger as one of the thermal management solutions.Conventionally manufactured heat exchangers had limitations that thwart the develop-ment of geometrically complex heat exchangers which are capable of exploiting topological aspects to enhance thermal performance.Subsequently,additive manufacturing(AM)is proposed as a powerful fabrication tech-nique for compact heat exchanger based on the mathematically known triply periodic minimal surfaces(TPMS).In this work,we present 3D compact crossflow heat exchanger computational fluid dynamics(CFD)modelling of geometrically complex structures based on TPMS using STARCCM+CFD platform.Moreover,CFD modelling is used to obtain new characteristics maps that relate heat transfer effectiveness(Ɛ)and number of transfer units for the proposed heat exchanger.The convection heat transfer coefficient,pressure drop,and inlet and outlet fluid temperature are all examined. 展开更多
关键词 Compact crossflow heat exchanger(CCHE) Additive manufacturing(AM) Triply periodic minimal surface(TPMS) Effectiveness(Ɛ) number of transfer units(NTU)
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