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Differential expression of glial cell line-derived neurotrophic factor splice variants in the mouse brain 被引量:1
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作者 Xiao-He Gu Heng Li +4 位作者 Lin Zhang Tao He Xiang Chai He Wei Dian-Shuai Gao 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第2期270-276,共7页
Glial cell line-derived neurotrophic factor(GDNF) plays a critical role in neuronal survival and function. GDNF has two major splice variants in the brain,α-pro-GDNF and β-pro-GDNF, and both isoforms have strong neu... Glial cell line-derived neurotrophic factor(GDNF) plays a critical role in neuronal survival and function. GDNF has two major splice variants in the brain,α-pro-GDNF and β-pro-GDNF, and both isoforms have strong neuroprotective effects on dopamine neurons. However, the expression of the GDNF splice variants in dopaminergic neurons in the brain remains unclear. Therefore, in this study, we investigated the mRNA and protein expression of α-and β-pro-GDNF in the mouse brain by real-time quantitative polymerase chain reaction, using splice variant-specific primers, and western blot analysis. At the mRNA level,β-pro-GDNF expression was significantly greater than that of α-pro-GDNF in the mouse brain. In contrast, at the protein level,α-pro-GDNF expression was markedly greater than that of β-pro-GDNF. To clarify the mechanism underlying this inverse relationship in mRNA and protein expression levels of the GDNF splice variants, we analyzed the expression of sorting protein-related receptor with A-type repeats(SorLA) by real-time quantitative polymerase chain reaction. At the mRNA level, SorLA was positively associated with β-pro-GDNF expression, but not with α-pro-GDNF expression. This suggests that the differential expression of α-and β-pro-GDNF in the mouse brain is related to SorLA expression. As a sorting protein, SorLA could contribute to the inverse relationship among the mRNA and protein levels of the GDNF isoforms. This study was approved by the Animal Ethics Committee of Xuzhou Medical University, China on July 14, 2016. 展开更多
关键词 Δ78 locus BRAIN region DOPAMINERGIC neurons glial cell line-derived NEUROTROPHIC factor mouse BRAIN precursor protein α-pro-GDNF β-pro-GDNF sorting protein-related receptor with A-type REPEATS splice variants
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Quantitative Comparative Study of the Performance of Lossless Compression Methods Based on a Text Data Model
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作者 Namogo Silué Sié Ouattara +1 位作者 Mouhamadou Dosso Alain Clément 《Open Journal of Applied Sciences》 2024年第7期1944-1962,共19页
Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their perform... Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their performance is exploited with lossy compression techniques for images and videos generally using a mixed approach. To achieve our intended objective, which is to study the performance of lossless compression methods, we first carried out a literature review, a summary of which enabled us to select the most relevant, namely the following: arithmetic coding, LZW, Tunstall’s algorithm, RLE, BWT, Huffman coding and Shannon-Fano. Secondly, we designed a purposive text dataset with a repeating pattern in order to test the behavior and effectiveness of the selected compression techniques. Thirdly, we designed the compression algorithms and developed the programs (scripts) in Matlab in order to test their performance. Finally, following the tests conducted on relevant data that we constructed according to a deliberate model, the results show that these methods presented in order of performance are very satisfactory:- LZW- Arithmetic coding- Tunstall algorithm- BWT + RLELikewise, it appears that on the one hand, the performance of certain techniques relative to others is strongly linked to the sequencing and/or recurrence of symbols that make up the message, and on the other hand, to the cumulative time of encoding and decoding. 展开更多
关键词 Arithmetic Coding BWT compression Ratio Comparative Study compression Techniques Shannon-Fano HUFFMAN Lossless compression LZW PERFORMANCE REDUNDANCY RLE Text Data Tunstall
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New Results in Perceptually Lossless Compression of Hyperspectral Images
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作者 Chiman Kwan Jude Larkin 《Journal of Signal and Information Processing》 2019年第3期96-124,共29页
Hyperspectral images (HSI) have hundreds of bands, which impose heavy burden on data storage and transmission bandwidth. Quite a few compression techniques have been explored for HSI in the past decades. One high perf... Hyperspectral images (HSI) have hundreds of bands, which impose heavy burden on data storage and transmission bandwidth. Quite a few compression techniques have been explored for HSI in the past decades. One high performing technique is the combination of principal component analysis (PCA) and JPEG-2000 (J2K). However, since there are several new compression codecs developed after J2K in the past 15 years, it is worthwhile to revisit this research area and investigate if there are better techniques for HSI compression. In this paper, we present some new results in HSI compression. We aim at perceptually lossless compression of HSI. Perceptually lossless means that the decompressed HSI data cube has a performance metric near 40 dBs in terms of peak-signal-to-noise ratio (PSNR) or human visual system (HVS) based metrics. The key idea is to compare several combinations of PCA and video/ image codecs. Three representative HSI data cubes were used in our studies. Four video/image codecs, including J2K, X264, X265, and Daala, have been investigated and four performance metrics were used in our comparative studies. Moreover, some alternative techniques such as video, split band, and PCA only approaches were also compared. It was observed that the combination of PCA and X264 yielded the best performance in terms of compression performance and computational complexity. In some cases, the PCA + X264 combination achieved more than 3 dBs than the PCA + J2K combination. 展开更多
关键词 Hyperspectral Images (HSI) compression Perceptually LOSSLESS Principal Component Analysis (PCA) Human Visual System (HVS) PSNR SSIM JPEG-2000 X264 X265 Daala
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An Improved SPIHT Algorithm for Image Compression in Low Bit Rate
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作者 Ping Liu Guanfeng Li 《Communications and Network》 2013年第3期245-248,共4页
Aiming at shortage of the SPIHT algorithm, an improved image compression algorithm is proposed, in order to overcome the shortcomings of decoding image quality and coding time, LS9/7 lifting wavelet transform is adopt... Aiming at shortage of the SPIHT algorithm, an improved image compression algorithm is proposed, in order to overcome the shortcomings of decoding image quality and coding time, LS9/7 lifting wavelet transform is adopted. According to the characteristics of the human visual system (HVS), the scanning mode and the method to determine the threshold of algorithm are changed to improve the quality of reconstruction image. On the question of repeating scan of SPIHT algorithm, using maximum list thought, greatly reduce the computation and save operating time. The experimental results have proved that the improved algorithm of image decoding time and the quality of reconstruction images are better than the original algorithm , especially in the case of low bit rate. 展开更多
关键词 WAVELET Transformation LIFTING Scheme THRESHOLD Set Partitioning in Hierarchical Trees(SPIHT) Human Visual System(HVS) Image compression Low BIT Rate
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热固性钼酚醛树脂的表征及其应用 被引量:8
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作者 强敏 张双庆 +1 位作者 林惠珊 陈林 《耐火材料》 EI CAS 北大核心 2005年第2期119-122,共4页
为了提高普通热固性酚醛树脂结合耐火材料的中温强度,采用IR和TG-DTA等手段分析了热固性钼酚醛树脂的结构和热性能,然后以热固性钼酚醛树脂作为结合剂制成铝碳砖试样,检测了铝碳砖试样的耐压强度、显气孔率和体积密度。结果表明:钼酚醛... 为了提高普通热固性酚醛树脂结合耐火材料的中温强度,采用IR和TG-DTA等手段分析了热固性钼酚醛树脂的结构和热性能,然后以热固性钼酚醛树脂作为结合剂制成铝碳砖试样,检测了铝碳砖试样的耐压强度、显气孔率和体积密度。结果表明:钼酚醛树脂是通过钼酸与酚醇中的羟甲基发生酯化反应,使钼以化学键的形式键合于酚醛树脂分子主链中而合成的;热固性钼酚醛树脂在质量损失率、热分解温度和树脂碳氧化温度等方面都比普通热固性酚醛树脂的有所改善,TG曲线在整个温度范围内的下降趋势也较平缓;热固性钼酚醛树脂结合的铝碳砖试样在200℃、500℃和600℃处理后的耐压强度分别比普通热固性酚醛树脂结合的提高了约23.1%、51.2%和70.3%,显气孔率也有所下降,体积密度有所提高。 展开更多
关键词 TG线 DTA 600 500
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Levels of v5 and v6 CD44 splice variants in serum of patients with colorectal cancer are not correlated with pT stage,histopathological grade of malignancy and clinical features 被引量:8
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作者 Bogdan Zalewski 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第4期583-585,共3页
AIM:This study was designed to compare the levels of v5 and v6 splice variants of CD44 evaluated using EITSA test in the serum of patients with colorectal cancer in different stages of progression of the disease estim... AIM:This study was designed to compare the levels of v5 and v6 splice variants of CD44 evaluated using EITSA test in the serum of patients with colorectal cancer in different stages of progression of the disease estimated in pT stage according to WHO score,histopathological grade of malignancy and some clinicopathological features. METHODS:The serum obtained from 114 persons with colorectal adenocarcinomas was examined using ELISA method,pT stage and grade of malignancy of the tumour were examined in formalin fixed and paraffin embedded materials obtained during operation. RESULTS:Only the level of CD44 v5 in the serum of patients before operation with G2 pT4 tumour was lower than that in other probes and the difference was statistically significant. We did not find any other correlations between the level of v5 and v6 CD44 variants and other evaluated parameters. CONCLUSION:The level of CD44 v5 and v6 estimated by ELISA test in the serum can not be used as a prognostic factor in colorectal cancer. 展开更多
关键词 Alternative Splicing ADENOCARCINOMA Adult Aged Aged 80 and over Antigens CD44 Colorectal Neoplasms Disease Progression Enzyme-Linked Immunosorbent Assay Female Humans Male Middle Aged Predictive Value of Tests Prognosis Tumor Markers Biological
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双相颗粒混合增韧ZrB_2陶瓷复合材料的研究 被引量:12
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作者 李金平 孟松鹤 +2 位作者 韩杰才 易法军 许承海 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2005年第6期727-729,共3页
将增韧相与ZrB2陶瓷基体按配比混料、热压,制备了双相颗粒混合增韧ZrB2陶瓷复合材料,研究了其密度、硬度、力学性能、耐烧蚀性能以及显微组织.结果表明,采用混料热压法能制备99.5%理论密度的ZrB2复合材料;显微硬度为800HV,室温抗压强度... 将增韧相与ZrB2陶瓷基体按配比混料、热压,制备了双相颗粒混合增韧ZrB2陶瓷复合材料,研究了其密度、硬度、力学性能、耐烧蚀性能以及显微组织.结果表明,采用混料热压法能制备99.5%理论密度的ZrB2复合材料;显微硬度为800HV,室温抗压强度为1.397GPa,相对压缩率为21.8%.随着温度升高,强度和压缩率均急剧下降;然而,到1100℃时抗压强度仍高达649MPa,相对压缩率为7.6%.该复合材料在等离子电弧加热器上烧蚀6s后,试样表面温升达2800℃,烧蚀后晶粒长大,部分韧化相熔化飞出,留下孔洞.在氧乙炔焰上烧蚀30s后,试样表面温升达到2000℃,烧蚀后表面无裂纹,表面形成一层氧化膜,晶粒略有长大. 展开更多
关键词 ZRB2
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New Approaches for Image Compression Using Neural Network
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作者 Vilas H. Gaidhane Vijander Singh +1 位作者 Yogesh V. Hote Mahendra Kumar 《Journal of Intelligent Learning Systems and Applications》 2011年第4期220-229,共10页
An image consists of large data and requires more space in the memory. The large data results in more transmission time from transmitter to receiver. The time consumption can be reduced by using data compression techn... An image consists of large data and requires more space in the memory. The large data results in more transmission time from transmitter to receiver. The time consumption can be reduced by using data compression techniques. In this technique, it is possible to eliminate the redundant data contained in an image. The compressed image requires less memory space and less time to transmit in the form of information from transmitter to receiver. Artificial neural net- work with feed forward back propagation technique can be used for image compression. In this paper, the Bipolar Coding Technique is proposed and implemented for image compression and obtained the better results as compared to Principal Component Analysis (PCA) technique. However, the LM algorithm is also proposed and implemented which can acts as a powerful technique for image compression. It is observed that the Bipolar Coding and LM algorithm suits the best for image compression and processing applications. 展开更多
关键词 Image compression FEED FORWARD Back Propagation Neural Network Principal Component Analysis (PCA) LEVENBERG-MARQUARDT (LM) Algorithm PSNR MSE
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Compression of ECG Signals Based on DWT and Exploiting the Correlation between ECG Signal Samples
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作者 Mohammed M. Abo-Zahhad Tarik K. Abdel-Hamid Abdelfatah M. Mohamed 《International Journal of Communications, Network and System Sciences》 2014年第1期53-70,共18页
This paper presents a hybrid technique for the compression of ECG signals based on DWT and exploiting the correlation between signal samples. It incorporates Discrete Wavelet Transform (DWT), Differential Pulse Code M... This paper presents a hybrid technique for the compression of ECG signals based on DWT and exploiting the correlation between signal samples. It incorporates Discrete Wavelet Transform (DWT), Differential Pulse Code Modulation (DPCM), and run-length coding techniques for the compression of different parts of the signal;where lossless compression is adopted in clinically relevant parts and lossy compression is used in those parts that are not clinically relevant. The proposed compression algorithm begins by segmenting the ECG signal into its main components (P-waves, QRS-complexes, T-waves, U-waves and the isoelectric waves). The resulting waves are grouped into Region of Interest (RoI) and Non Region of Interest (NonRoI) parts. Consequently, lossless and lossy compression schemes are applied to the RoI and NonRoI parts respectively. Ideally we would like to compress the signal losslessly, but in many applications this is not an option. Thus, given a fixed bit budget, it makes sense to spend more bits to represent those parts of the signal that belong to a specific RoI and, thus, reconstruct them with higher fidelity, while allowing other parts to suffer larger distortion. For this purpose, the correlation between the successive samples of the RoI part is utilized by adopting DPCM approach. However the NonRoI part is compressed using DWT, thresholding and coding techniques. The wavelet transformation is used for concentrating the signal energy into a small number of transform coefficients. Compression is then achieved by selecting a subset of the most relevant coefficients which afterwards are efficiently coded. Illustrative examples are given to demonstrate thresholding based on energy packing efficiency strategy, coding of DWT coefficients and data packetizing. The performance of the proposed algorithm is tested in terms of the compression ratio and the PRD distortion metrics for the compression of 10 seconds of data extracted from records 100 and 117 of MIT-BIH database. The obtained results revealed that the proposed technique possesses higher compression ratios and lower PRD compared to the other wavelet transformation techniques. The principal advantages of the proposed approach are: 1) the deployment of different compression schemes to compress different ECG parts to reduce the correlation between consecutive signal samples;and 2) getting high compression ratios with acceptable reconstruction signal quality compared to the recently published results. 展开更多
关键词 ECG Signal Segmentation LOSSLESS and LOSSY compression Techniques Discrete Wavelet Transform Energy PACKING Efficiency RUN-LENGTH Coding
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Achievements of Truss Models for Reinforced Concrete Structures 被引量:2
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作者 P. G. Papadopoulos H. Xenidis +3 位作者 P. Lazaridis A. Diamantopoulos P. Lambrou Y. Arethas 《Open Journal of Civil Engineering》 2012年第3期125-131,共7页
Achievements are presented for truss models of RC structures developed in previous years: 1. Two constitutive models, biaxial and triaxial, are based on regular trusses, with bars obeying nonlinear uniaxial σ-ε laws... Achievements are presented for truss models of RC structures developed in previous years: 1. Two constitutive models, biaxial and triaxial, are based on regular trusses, with bars obeying nonlinear uniaxial σ-ε laws of material under simulation;both models have been compared with test results and show a dependence of Poisson ratio on curvature of σ-ε law. 2. A truss finite element has been used in the nonlinear static and dynamic analysis of plane RC frames;it has been compared with test results and describes, in a simple way, the formation of plastic hinges. 3. Thanks to the very simple geometry of a truss, the equilibrium equations can be easily written and the stiffness matrix can be easily updated, both with respect to the deformed truss, within each step of a static incremental loading or within each time step of a dynamic analysis, so that to take into account geometric nonlinearities. So the confinement of a RC column is interpreted as a structural stability effect of concrete. And a significant role of the transverse reinforcement is revealed, that of preventing, by its close spacing and sufficient amount, the buckling of inner longitudinal concrete struts, which would lead to a global instability of the RC column. 4. The proposed truss model is statically indeterminate, so it exhibits some features, which are not met by the “strut-and-tie” model. 展开更多
关键词 Reinforced CONCRETE Structure TRUSS Model CONSTITUTIVE Law Material and Geometric NONLINEARITIES CONCRETE Cracking Reinforcement Yield CONCRETE ULTIMATE Compressive Strength Plastic HINGE RC Column Confinement Buckling of Inner CONCRETE Struts Global Instability
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Injection Strategy in Natural Gas–Diesel Dual-Fuel Premixed Charge Compression Ignition Combustion under Low Load Conditions 被引量:4
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作者 Hyunwook Park Euijoon Shim Choongsik Bae 《Engineering》 SCIE EI 2019年第3期548-557,共10页
Dual-fuel premixed charge compression ignition (DF-PCCI) combustion has been proven to be a viable alternative to conventional diesel combustion in heavy-duty compression ignition engines due to its low nitrogen oxide... Dual-fuel premixed charge compression ignition (DF-PCCI) combustion has been proven to be a viable alternative to conventional diesel combustion in heavy-duty compression ignition engines due to its low nitrogen oxides (NOx) and particulate matter (PM) emissions. When natural gas (NG) is applied to a DF-PCCI engine, its low reactivity reduces the maximum pressure rise rate under high loads. However, the NG–diesel DF-PCCI engine suffers from low combustion efficiency under low loads. In this study, an injection strategy of fuel supply (NG and diesel) in a DF-PCCI engine was investigated in order to reduce both the fuel consumption and hydrocarbon (HC) and carbon monoxide (CO) emissions under low load conditions. A variation in the NG substitution and diesel start of energizing (SOE) was found to effectively control the formation of the fuel–air mixture. A double injection strategy of diesel was implemented to adjust the local reactivity of the mixture. Retardation of the diesel pilot SOE and a low fraction of the diesel pilot injection quantity were favorable for reducing the combustion loss. The introduction of exhaust gas recirculation (EGR) improved the fuel economy and reduced the NOx and PM emissions below Euro VI regulations by retarding the combustion phasing. The combination of an NG substitution of 40%, the double injection strategy of diesel, and a moderate EGR rate effectively improved the combustion efficiency and indicated efficiency, and reduced the HC and CO emissions under low load conditions. 展开更多
关键词 DUAL FUEL REACTIVITY controlled compression IGNITION PREMIXED charge Natural gas Injection strategy EXHAUST recirculation
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新疆哈尔里克山二叠纪碱性花岗岩-石英正长岩组合的成因及其构造意义 被引量:14
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作者 汪传胜 顾连兴 +5 位作者 张遵忠 吴昌志 唐俊华 三金柱 黎广荣 李中华 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3182-3196,共15页
哈尔里克奥姆尔塔格碱性花岗岩(OMAG)侵入于小铺东二长花岗岩中。该岩体岩性较均一,呈灰紫色,主要矿物组合为石英、钾长石、钠长石、碱性角闪石和霓石;化学成分上富硅、碱,贫钙、镁,低铝;富Rb、Th、U和Zr,Ga/Al比值大(3.18×10~4~3... 哈尔里克奥姆尔塔格碱性花岗岩(OMAG)侵入于小铺东二长花岗岩中。该岩体岩性较均一,呈灰紫色,主要矿物组合为石英、钾长石、钠长石、碱性角闪石和霓石;化学成分上富硅、碱,贫钙、镁,低铝;富Rb、Th、U和Zr,Ga/Al比值大(3.18×10~4~3.56×10~4),贫Ba、Sr,岩石中Co、Cr、V和Ni等过渡元素显著亏损,U、Hf、Zr和Nb等高场强元素的含量高;稀土总量较高,配分模式右倾,并具有显著的负铕异常;LA-ICP-MS锆石^(206)Pb/^(238)U加权平均年龄为287.6±2.1Ma;具有正的ε_(Nd)(t)值(+4.96),较低的(^(87)Sr/^(86)Sr),值(0.70159)。同样侵入于小铺东二长花岗岩中的恰干昆多沟含角闪石石英正长岩(QGQS)也呈灰紫色,其结构和构造与OMAG非常相似。两个岩体在主量元素和REE图解上均呈现有规律的分布和一致的演化趋势。从QGQS到OMAG,SiO_2含量增加(从64.71%~64.83%到71.23%~74.31%)、全碱含量降低(从11.72%~11.79%到8.49%~9.87%)和Al_2O_3含量减少(从16.09%~16.19%到11.44%~13.34%)、稀土总量减少(从592.3×10^(-6)~656.0×10^(-6)到273.9×10^(-6)~405.9×10^(-6))、轻/重稀土比值降低(从18.2~20.1到4.4~6.0)、稀土配分曲线从平滑到Eu显著亏损。基于OMAG的岩相学、矿物学、地球化学、锆石年代学和与QGQS的对比研究,笔者认为奥姆尔塔格碱性花岗岩可能是由石英正长岩母岩浆经过分离结晶作用演化的产物,且这种石英正长岩岩浆起源于亏损地幔;根据哈尔里克造山带地质演化历史的分析,这两个岩体均形成于紧随主碰撞后的挤压-伸展转折阶段。 展开更多
关键词 distribution patterns fractional crystallization comparative study compression
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A methodology to determine the elastic properties of anisotropic rocks from a single uniaxial compression test 被引量:4
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作者 Morteza Nejati Marie Luise Texas Dambly Martin OSaar 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第6期1166-1183,共18页
This paper introduces a new methodology to measure the elastic constants of transversely isotropic rocks from a single uniaxial compression test.We first give the mathematical proof that a uniaxial compression test pr... This paper introduces a new methodology to measure the elastic constants of transversely isotropic rocks from a single uniaxial compression test.We first give the mathematical proof that a uniaxial compression test provides only four independent strain equations.As a result,the exact determination of all five independent elastic constants from only one test is not possible.An approximate determination of the Young’s moduli and the Poisson’s ratios is however practical and efficient when adding the Saint-Venant relation as the fifth equation.Explicit formulae are then developed to calculate both secant and tangent definitions of the five elastic constants from a minimum of four strain measurements.The results of this new methodology applied on three granitic samples demonstrate a significant stress-induced nonlinear behavior,where the tangent moduli increase by a factor of three to four when the rock is loaded up to 20 MPa.The static elastic constants obtained from the uniaxial compression test are also found to be significantly smaller than the dynamic ones obtained from the ultrasonic measurements. 展开更多
关键词 Transversely ISOTROPIC rock ELASTIC CONSTANTS Youngs MODULUS Poissons ratio Seismic anisotropy UNIAXIAL compression GRANITE
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Intermittent Pneumatic Compression in Treatment of Chronic Venous Leg Ulcers: A Case Report and Review of Literature
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作者 Ali Kordzadeh Attila Jonas Yiannis P. Panayiotopoulos 《Case Reports in Clinical Medicine》 2014年第9期513-517,共5页
Introduction: The benefit of intermittent pneumatic compression (IPC) for the prevention of venous thromboembolism and lymphedema has been well established in the literature. Recent evidence suggests that IPC plays a ... Introduction: The benefit of intermittent pneumatic compression (IPC) for the prevention of venous thromboembolism and lymphedema has been well established in the literature. Recent evidence suggests that IPC plays a beneficial role in circulation, hemodynamic peripheral pump, intravascular coagulation and arterial skin perfusion. Despite such evidence, the use of IPC in the treatment of resistant and chronic venous leg ulcers, has received little attention in practice. Case Presentation: We would like to report the case of successfully treated chronic and bilateral venous leg ulcer in an obese patient with IPC application and a review of the literature. Results: The use of IPC as an adjuvant therapy to the traditional multilayered compression therapy permitted significant resolution of the ulcers, reduced secondary infection incidence and prevented ulcer recurrence. Conclusion: In obese, minimally mobile patients with venous ulcers not responding to the traditional multilayered compression therapy application of IPC, an adjuvant therapy is recommended. 展开更多
关键词 Intermittent Pneumatic compression (IPC) CHRONIC VENOUS LEG ULCERS Bilateral VENOUS LEG ULCER Management compression Therapy OBESE Patient Follow-Up
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Towards a Classification of Left Common Iliac Vein Compression Based on Triplanar Phlebography
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作者 Raymond Englund 《Surgical Science》 2017年第1期19-26,共8页
Introduction: There is currently no consistent classification of the extent of left common iliac vein compression syndromes such that clinicians working in the area have a common terminology. Hypothesis: To create a c... Introduction: There is currently no consistent classification of the extent of left common iliac vein compression syndromes such that clinicians working in the area have a common terminology. Hypothesis: To create a classification of left common iliac vein compression based on the end point of triplanar pelvic phlebogrpahy. Methods: Based on 61 consecutive patients found to have left common iliac vein compression on triplanar phlebography in the course of treatment of venous disease, clinical presentation and symptomatology were retrospectively used to create a classification of left common iliac vein compression. Treatment of left common iliac vein compression was also retrospectively correlated with staging. Results: The following classification was arrived at: Stage 0, no compression and no intraluminal fibrous bands;Stage 1, evidence of compression by surrounding anatomical structures with or without the presence of fibrous bands;Stage 2: evidence of compression with or without fibrous bands as evidenced by cross-pelvic collaterals;Stage 3: compression of the left common iliac vein. Fibrous bands replaced by localised occlusion, with collateralisation and no involvement of adjacent venous segments;Stage 4a: as for Stage 3 but with the addition of thrombotic involvement of adjacent venous segments;Stage 4b: as for Stage 4a but with involvement of distal venous segments, femoral and popliteal. Stages 3, 4a or 4b correlated well with clinical presentations of DVT, PE, venous ulceration, vulval or cross-pelvic collaterals, ipsilateral limb swelling and claudication. The presence of varicose veins or recurrent varicose veins was a common finding amongst all groups. Conclusion: Acceptance of this classification system would provide a common terminology to allow more transparent assessment of modalities of treatment for this condition. 展开更多
关键词 May Thurner Syndrome Left Common ILIAC Vein compression VENOUS COLLATERALS VENOUS Hypertensive Disease Cross-Pelvic COLLATERALS VARICOSE VEINS
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混合液治疗老年病人大面积深度压疮的效果观察 被引量:5
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作者 林静茹 郭惠珍 +2 位作者 简爱华 邹海容 江玉棉 《现代临床护理》 2005年第2期56-57,共2页
目的探讨用胰岛素、山莨菪碱、氯霉素混合液进行封闭式湿敷并配合清创、冲洗方法治疗20例老年病人大面积深度压疮的效果。方法回顾性分析20例(25处)大面积深度压疮的老年病人经采用清创、冲洗,胰岛素、山莨菪碱、氯霉素混合液封闭式湿... 目的探讨用胰岛素、山莨菪碱、氯霉素混合液进行封闭式湿敷并配合清创、冲洗方法治疗20例老年病人大面积深度压疮的效果。方法回顾性分析20例(25处)大面积深度压疮的老年病人经采用清创、冲洗,胰岛素、山莨菪碱、氯霉素混合液封闭式湿敷治疗的效果。结果25处压疮的脓性分泌物均在湿敷后第2天明显减少,同时肉芽组织开始生长;1周后渗出液完全消失,肉芽组织快速生长。治愈时间20±6.0d。25处压疮治愈23处,除1例病人(2处压疮)因心力衰竭抢救无效死亡外,其他均治愈,治愈率92.0%。结论混合液可尽快清除压疮创面的脓性分泌物,使用混合液治疗压疮可促使肉芽组织生长迅速,创面修复快,换药时敷料易于揭开不损伤肉芽,减轻了病人的痛苦。 展开更多
关键词 湿
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Study on the Constitutive Model of Marble Based on the Conventional Triaxial Compression Test
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作者 Tian Sheng-li Lu Yun-de Ge Xiu-run 《上海交通大学学报》 EI CAS CSCD 北大核心 2004年第z2期8-13,共6页
The RMB-150B rock mechanics test system was employed to obtain the complete stress-strain test curves under confining pressures of 0-30MPa for marble samples from Ya'an ,Sichuan province. On the basis of former st... The RMB-150B rock mechanics test system was employed to obtain the complete stress-strain test curves under confining pressures of 0-30MPa for marble samples from Ya'an ,Sichuan province. On the basis of former study and the convention triaxial pressure test results ,the complete procedures curves which described the relationships between yielding strength、 peak strength、 residual strength and confining pressure was obtained. Taking the strain softening of rock into account, the bilinear elastic-linear softening-residual perfect plasticity four-linear model was put forward in this paper on the basis of the test results and theory of plasticity. This model was adopted to describe the behaviors of marble in different phases under triaxial compression with the constitutive equation of strain softening phase as focus. The results indicated that the theoretic model fitted in well with the test results. 展开更多
关键词 theory of PLASTICITY conventional TRIAXIAL compression test CONSTITUTIVE model control equation linear SOFTENING BILINEAR elastic
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测井信息在前陆挤压区地应力分析中的应用 被引量:7
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作者 赵军 蒲万丽 +1 位作者 王贵文 李军 《地质力学学报》 CSCD 2005年第1期53-59,共7页
中国西部前陆盆地主要以挤压构造应力为主,地表与地下构造异常复杂。在油气的勘探与开发过程中既需要精细的地应力研究与预测,也需要简单易行、经济实用的近似方法。本文通过对稳定构造地区与挤压构造区地球物理测井信息的深度域特征进... 中国西部前陆盆地主要以挤压构造应力为主,地表与地下构造异常复杂。在油气的勘探与开发过程中既需要精细的地应力研究与预测,也需要简单易行、经济实用的近似方法。本文通过对稳定构造地区与挤压构造区地球物理测井信息的深度域特征进行分析和对比,提出了一种基于测井信息来计算最大岩石主应力的统计模型法。应用该方法对塔里木盆地库车山前挤压应力区进行了实际计算,其结果与实验结果相符。在此基础上对山前挤压区地应力与油气藏分布的关系进行了探索。 展开更多
关键词 西
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Minimally Invasive Open Reduction and Internal Fixation for Osteoporotic Vertebral Compression Fractures: Technical Report and Mid-Term Outcomes 被引量:1
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作者 Jui-Yang Hsieh Po-Quang Chen Jyh-Horng Wang 《Open Journal of Orthopedics》 2018年第9期337-350,共14页
Background: Traditional open instrumentation may cause surgical complications due to fragile bones and induce medical comorbidities in senile patients. Vertebroplasty and kyphoplasty are palliative augmentation proced... Background: Traditional open instrumentation may cause surgical complications due to fragile bones and induce medical comorbidities in senile patients. Vertebroplasty and kyphoplasty are palliative augmentation procedures that have been associated with increased risks of cement leakage, adjacent fractures and non-union. Objective: The aim of this study was to describe a novel approach for the union of osteoporotic vertebral compression fractures with minimally invasive open reduction and internal fixation. Patients and Methods: Seven consecutive patients with intractable back pain without neurological deficits due to osteoporotic vertebral compression fractures were treated using minimally invasive fixation with intra-vertebral expandable pillars and artificial bone substitute. The clinical symptoms and image findings were recorded. Results: All of the patients reported relief of back pain, and the height of the vertebral bodies was well restored. X-ray findings obtained 2 to 4 years after the procedures showed fracture healing and favorable formation of the callus confirmed in the anterior longitudinal ligament. Conclusion: This mini-open procedure with intravertebral devices is an effective and reliable technique for osteoporotic vertebral compression fractures and may avoid complications related to traditional open spinal instrumentation procedures and augmentation with bone cement. 展开更多
关键词 OSTEOPOROTIC VERTEBRAL compression FRACTURE MINIMALLY Invasive Spine Surgery Intra-Vertebral EXPANDABLE PILLAR FRACTURE Union Bone Cement
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Nonlinear Study on the Mechanical Performance of Built-Up Cold-Formed Steel Concrete-Filled Columns under Compression
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作者 Oulfa Harrat Yazid Hadidane +4 位作者 S.M.Anas Nadhim Hamah Sor Ahmed Farouk Deifalla Paul O.Awoyera Nadia Gouider 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3435-3465,共31页
Given their numerous functional and architectural benefits,such as improved bearing capacity and increased resistance to elastic instability modes,cold-formed steel(CFS)built-up sections have become increasingly devel... Given their numerous functional and architectural benefits,such as improved bearing capacity and increased resistance to elastic instability modes,cold-formed steel(CFS)built-up sections have become increasingly developed and used in recent years,particularly in the construction industry.This paper presents an analytical and numerical study of assembled CFS two single channel-shaped columns with different slenderness and configurations(backto-back,face-to-face,and box).These columns were joined by double-row rivets for the back-to-back and box configurations,whereas they were welded together for the face-to-face design.The built-up columns were filled with ordinary concrete of good strength.Finite element models were applied,using ABAQUS software,to assess mechanical performance and study the influence of assembly techniques on the behavior of cold-formed columns under axial compression.Analytical approaches based on Eurocode 3 and Eurocode 4 recommendations for un-filled and concrete-filled columns respectively were followed for the numerical analysis,and concrete confinement effects were also considered per American Concrete Institute(ACI)standards for face-to-face and box configurations.The obtained results indicated a good correlation between the numerical results and the proposed analytical methodology which did not exceed 8%.The failure modes showed that the columns failed due to instabilities such as local and global buckling. 展开更多
关键词 Cold-formed steel built-up sections SLENDERNESS rivets WELDED axial compression analytical approaches CONFINEMENT BUCKLING
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