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腹、盆部Castleman病的CT表现与病理对照 被引量:6
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作者 王昌盛 宋立强 《中国CT和MRI杂志》 2015年第1期75-77,85,共4页
目的探讨腹、盆部Castleman病(Castleman disease,CD)的CT特征,并与病理学对照。方法回顾性分析11例经手术病理证实CD的CT及病理资料。结果 17例位于腹膜后,3例位于肠系膜根部,1例位于髂血管走行区。局限型10例,为透明血管型,弥漫型1例... 目的探讨腹、盆部Castleman病(Castleman disease,CD)的CT特征,并与病理学对照。方法回顾性分析11例经手术病理证实CD的CT及病理资料。结果 17例位于腹膜后,3例位于肠系膜根部,1例位于髂血管走行区。局限型10例,为透明血管型,弥漫型1例为浆细胞型。2CT平扫10例呈等密度,1例为稍低密度,密度均匀,均无囊变坏死,2例中心见分支状钙化。CT增强:7例动脉期不均匀显著强化,3例中度均匀强化,1例轻度均匀强化,5例见明显强化血管;静脉期8例持续均匀强化,3例中心填充强化;延迟期均呈较均匀稍高密度。结论腹、盆部CD的CT表现与病理类型密切相关,尤其是透明血管型CD表现具有一定特征,CT检查对CD诊断具有重要价值。 展开更多
关键词 CAST 1eman病 腹部 体层摄影术 X线计算机
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单颗粒重构软件EMAN算法分析与高效并行实现
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作者 樊莉亚 张法 +1 位作者 王功明 刘志勇 《计算机研究与发展》 EI CSCD 北大核心 2010年第12期2165-2176,共12页
单颗粒重构技术是确定大分子三维结构的重要手段之一.近年来,由于其本身独有的一些优点,单颗粒重构技术受到越来越广泛的关注.然而其处理过程极其耗时,并且缺少高效的并行实现,极大地限制了该技术的应用.对当今使用最广泛的单颗粒重构软... 单颗粒重构技术是确定大分子三维结构的重要手段之一.近年来,由于其本身独有的一些优点,单颗粒重构技术受到越来越广泛的关注.然而其处理过程极其耗时,并且缺少高效的并行实现,极大地限制了该技术的应用.对当今使用最广泛的单颗粒重构软件EMAN进行了性能优化及并行加速.通过分析各部分的具体算法,发现其中最核心的问题是如何在低通信开销的前提下实现负载平衡.针对这一问题,提出了自适应动态调度算法.该算法不仅适合于EMAN,同样适合于其他类似的独立任务调度问题.实际运行结果表明,经过优化的串行程序运行时间减少11.50%.由于采用了自适应动态调度算法,提供的并行实现比EMAN自带的实现具有更高的加速比,其中最耗时的分类操作加速比接近线性.在16个处理器核上的总体并行效率比EMAN自带的并行实现高29.8%.因此,提供的并行实现可有效利用计算资源,显著缩短单颗粒重构所需时间. 展开更多
关键词 生物信息 并行计算 调度算法 EMAN 单颗粒重构
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Emanation-Sedimentary Metallogenic Series and Models of the Proterozoic Rift in the Kangdian Axis 被引量:4
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作者 QIN Dexian LIU Chunxue 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期466-472,共7页
The Kangdian axis basement can be divided into two tectonic layers. The lower tectonic layer is the crystalline basement which is made up of the Archaean Dibadu Formation and early Proterozoic Dahongshan Group. The fo... The Kangdian axis basement can be divided into two tectonic layers. The lower tectonic layer is the crystalline basement which is made up of the Archaean Dibadu Formation and early Proterozoic Dahongshan Group. The former is a kata-metamorphic basic volcano-sedimentary formation of the old geosyncline (old continental nucleus), and the latter is a medium-grade metamorphosed alkali-rich basic volcanic (emanation)-sedimentary formation of the Yuanjiang-Dahongshan marginal rift. They are in disconformable contact. The upper tectonic layer is the folded basement, and made up of the middle-late Proterozoic Kunyang Group. It is the result of Dongchuan-Yuanjiang intercontinental rifting with discordant contract with the underlying and overlying strata. Along with the evolution of Proterozoic from early to late, four types of emanation-sedimentary deposits in the Kangdian axis rift were formed in turn: emanation-sedimentary iron-copper-gold deposits related to basic volcanic rocks in the Yuanmou-Dahongshan marginal rift; emanation-sedimentary iron-copper deposits related to intermediate-basic volcanic rocks in the early stage of the Dongnchuan-Yuanjiang intercontinental rift; emanation-sedimentary copper deposits related to sedimentary rocks in the middle stage; copper deposits related to the late tectonic reworking. From early to late Proterozoic, with the evolution of the Kangdian axis rift and lowering volcanic basicity, the ore-forming elements also evolved from Fe, Cu and (Au) through Cu and Fe to Cu. 展开更多
关键词 metallogenic series and model rift evolution emanated hot water Kangdian axis
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Radiological characterization of building materials used in Malaysia and assessment of external and internal doses 被引量:1
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作者 Shittu Abdullahi Aznan Fazli Ismail Supian Samat 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第3期82-96,共15页
In this study, the activity concentrations of ^(226)Ra,^(232)Th,^(222)Rn, and ^(40)K, emanation fractions(P),equilibrium equivalent concentration(EEC), and mass exhalation rates(E_m) of radon released from building ma... In this study, the activity concentrations of ^(226)Ra,^(232)Th,^(222)Rn, and ^(40)K, emanation fractions(P),equilibrium equivalent concentration(EEC), and mass exhalation rates(E_m) of radon released from building materials used in Malaysia were studied using gamma-ray spectrometer with HPGe detector. Radiological parameters[activity concentration index(ACI), indoor air-absorbed dose rate(D_(in)), annual effective dose(AED_(in)) from external and internal(E_(Rn)), soft tissues(H_(ST)) and lung(H_L), and effective dose equivalent(H_(eff))] were estimated to evaluate radiological hazards due to the use of these building materials: sand, cement, gravel, bricks, tiles, fly ash, white cement, and ceramic raw materials. The measured P, EEC,and E_m vary from 10 to 30%, 0.9 to 22 Bq m^(-3), and 33 to 674 mBq h^(-1) kg^(-1), respectively, while the calculated ACI and AED_(in) vary from 0.1 ± 0.01 to 2.1 ± 0.1 and 0.1 ± 0.01 to 2.4 ± 0.6 mSv y^(-1), respectively. On the other hand, the internal annual effective dose ranges from 0.1 to 1.4 mSv y^(-1). The estimated radiological risk parameters were below the recommended maximum values, and radiological hazards associated with building materials under investigation are therefore negligible. 展开更多
关键词 Indoor radon EMANATION fraction Equilibrium EQUIVALENT concentration Mass EXHALATION rate Annual EFFECTIVE DOSE EFFECTIVE DOSE EQUIVALENT
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Neutron activation analysis of ceramic tiles and its component and radon exhalation rate
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作者 A.El-Shershaby A.Sroor +2 位作者 F.Ahmed A.S.Abdel-Haleem Z.Abdel 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期94-99,共6页
The concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) technique. The samples and standard were irradiate... The concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) technique. The samples and standard were irradiated with reactor for 4 h(in the Second Research Egyptian Reactor(Et-RR-2)) with thermal neutron flux 5.9×10 13 n/(cm 2·s).The gamma-ray spectra obtained were measured for several times by means of the hyper pure germanium detection system(HPGe). Also a solid state nuclear track detector(SSNTD) CR-39, was used to measure the emanation rate of radon for these samples. The radium concentrations were found to vary from 0.39—3.59 ppm and the emanation rates were found to vary from (0.728—5.688) × 10 -4 kg/(m 2· s).The elemental analysis of the ceramic tiles and ceramic composites have a great importance in assigning the physical properties and in turn the quality of the material. 展开更多
关键词 CERAMIC neutron activation analysis(NAA) radon emanation solid state nuclear track detector(SSNTD)
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STRESS INTENSITY FACTORS OF A PLATE WITH TWO CRACKS EMANATING FROM AN ARBITRARY HOLE
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作者 王元汉 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第8期723-732,共10页
In this paper, Muskhelishvili complex function theory and boundary collocation method are used to calculate the stress intensity factors (SIF) of a plate with two cracks emanating from an arbitrary hole. The calculate... In this paper, Muskhelishvili complex function theory and boundary collocation method are used to calculate the stress intensity factors (SIF) of a plate with two cracks emanating from an arbitrary hole. The calculated examples include a circular, elliptical, rectangular, or rhombic hole in a plate. The principle and procedure by the method is not only rather simple, but also has good accuracy. The SIF values calculated compare very favorably with the existing solutions. A t the same time,the method can be used far different finite plate with two cracks emanating from a hole with more complex geometrical and loading conditions. It is an effective unified approach for this kind of fracture problems. 展开更多
关键词 mode STRESS INTENSITY FACTORS OF A PLATE WITH TWO CRACKS EMANATING FROM AN ARBITRARY HOLE LENGTH
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THE SOLUTION OF A CRACK EMANATING FROM AN ARBITRARY HOLE BY BOUNDARY COLLOCATION METHOD
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作者 王元汉 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第7期669-678,共10页
In this paper a group of stress functions has been proposed for the calculation of a crack emanating from a hole with different shape (including circular, elliptical, rectangular, or rhombic hole) by boundary collocat... In this paper a group of stress functions has been proposed for the calculation of a crack emanating from a hole with different shape (including circular, elliptical, rectangular, or rhombic hole) by boundary collocation method. The calculation results show that they coincide very well with the existing solutions by other methods for a circular or elliptical hole with a crack in an infinite plate. At the smae time, a series of results for different holes in a finite plate has also been obtained in this paper. The proposed functions and calculation procedure can be used for a plate of a crack emanating from an arbitrary hole. 展开更多
关键词 THE SOLUTION OF A CRACK EMANATING FROM AN ARBITRARY HOLE BY BOUNDARY COLLOCATION METHOD LENGTH
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Trials for Gathering Information on an Unknown Peak in the GC-MS Spectra of Horse and Pony Hair Extracts
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作者 Maia Tsikolia Till Opatz +5 位作者 Ulrich Kauhl Nurhayat Tabanca Betul Demirci Saundra H. TenBroeck Kenneth J. Linthicum Ulrich R. Bernier 《Advances in Entomology》 2021年第2期100-111,共12页
The volatile compounds from horse and pony hairs and skin were analyzed to determine bioactive molecules that are kairomones used for host location by blood-feeding diptera. In this study, horse and pony hair samples ... The volatile compounds from horse and pony hairs and skin were analyzed to determine bioactive molecules that are kairomones used for host location by blood-feeding diptera. In this study, horse and pony hair samples were extracted with organic solvents (pentane or hexane) and analyzed by gas chromatography-mass spectrometry analysis (GC-MS) with closed electron ionization (CEI). Using the GC-MS analysis, we observed a compound peak, which could not be identified by comparison to mass spectra in the mass spectral library. This unknown compound was often the largest peak in the chromatogram and had a retention index and mass spectral fragmentation similar to nonanal. However, there were several differences in the fragmentation pattern. When compared to a nonanal reference standard, it was evident that this was a different compound. Hydrodistillation of pony hair was another extraction method to obtain the unknown component in higher concentrations. Analysis of this extract with GC-flame ionization detector (FID) with GC-MS confirmed the same unknown peak. Further experiments and analysis with the various mass spectroscopy tools gave the possible molecular ion with mass-to-charge ratio (<em>m/z</em>) 142, corresponding to the unknown component. 展开更多
关键词 Nonanal Skin Emanation Insect Pests Equus caballus Equus ferus caballus Mass Spectroscopy Structure Elucidation
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Advances in herpetological research emanating from China
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作者 Robert W.MURPHY the State Key Laboratory of Genetic Resources and Evolution,Kunming Institute of Zoology,Chinese Academy of Sciences and the Centre for Biodiversity and Conservation Biology,Royal Ontario Museum 《Zoological Research》 CAS CSCD 2016年第1期4-6,共3页
The warming of Earth owing to human activities is resulting in an episode of mass extinction. If global warming is not abated quickly, up to one-fourth of the species on our planet will face extinction in only 35 year... The warming of Earth owing to human activities is resulting in an episode of mass extinction. If global warming is not abated quickly, up to one-fourth of the species on our planet will face extinction in only 35 years. The loss of biodiversity is more than just many species disappearing. It could signal the beginning of the collapse of our ecosystems because the loss of one species can trigger a domino effect. Among vertebrates, the so-called cold bloodied species--fishes, amphibians and reptiles--are the most threatened groups. 展开更多
关键词 Advances in herpetological research emanating from China
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Zou Hengyu, China's No.1 Maker of Radium Emanated Leather Products
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《China's Foreign Trade》 2001年第9期12-13,共2页
关键词 AS China’s No.1 Maker of Radium Emanated Leather Products Zou Hengyu
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加拿大生态监测评估网(EMAN)
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作者 董连成 《资源生态环境网络研究动态》 1999年第3期45-46,共2页
关键词 加拿大 生态监测评估网 EMAN 环境监测
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Method for determining the best frequency band for eavesdropping the display image of a PC
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作者 DU Yu-lei Lü Ying-hua +1 位作者 ZHANG Jin-ling ZHANG Nan 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2013年第4期93-98,共6页
The display image of the video display unit (VDU) can be reconstructed by receiving and analyzing the unexpected electromagnetic noise emanated from a personal computer system. This fact is one of the information le... The display image of the video display unit (VDU) can be reconstructed by receiving and analyzing the unexpected electromagnetic noise emanated from a personal computer system. This fact is one of the information leakage threats in information security. Therefore, in order to choose the best frequency range for receiving the electromagnetic compromising emanations form a PC display effectively and quickly, a method based on the correlation power analysis (CPA) and the common equipments is proposed. Firstly, the frequency spectrum of 10 MHz to 1 GHz is measured about 10 times respectively when the PC is displaying the white-black vertical strips image and black image. The frequency range which contains the display information can be obtained through the CPA. And then, the special image signal is searched around the dot frequency and harmonics. If the special signal disappears when displaying the total black image, it can be judged to be the real special signal. Finally, the best receiving frequency range can be chosen by comprehensive considering the results of CPA and the signal to noise ratio (SNR) of the special image signal. In order to check the validity of the chosen frequency range, eavesdropping experiments are carried out. The results demonstrate that the selected frequency range can retrieve the higher quality image than other frequency bands. 展开更多
关键词 electromagnetic secure compromising emanations CPA EAVESDROPPING TEMPEST
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GPU机群系统上加速EMAN(英文) 被引量:1
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作者 李兴建 谭光明 郭子昱 《生物物理学报》 CAS CSCD 北大核心 2010年第7期600-605,共6页
近年来,高质量的三维重构对计算机系统的计算能力提出越来越高的需求。EMAN是对冷冻电子显微镜拍摄出来的图像进行单颗粒三维重构的流行软件包。由于GPU显示出优于CPU的性能水平,在GPU机群系统上对EMAN进行加速将有可能取得较好的效果... 近年来,高质量的三维重构对计算机系统的计算能力提出越来越高的需求。EMAN是对冷冻电子显微镜拍摄出来的图像进行单颗粒三维重构的流行软件包。由于GPU显示出优于CPU的性能水平,在GPU机群系统上对EMAN进行加速将有可能取得较好的效果。首先,有必要调查EMAN在计算方面的特点,包括计算密度,访存情况和并行潜力。结果显示其在GPU体系结构上有获得较高性能的潜力。然后,根据此特点完成一款并行EMAN软件,使用CUDA和MPI对EMAN实施不同粒度的并行处理。在一个拥有16颗Intel6核处理器的机群系统上,用8颗FermiGPU加速后的EMAN(CUDA-EMAN)相比于仅使用CPU的并行EMAN程序获得了2.5倍的加速比,也就是1颗FermiGPU相比一个Intel6核处理器可对EMAN加速5倍。 展开更多
关键词 EMAN GPU CUDA 并行 三维重构
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Stress emission of helium and argon in coal seams 被引量:3
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作者 朱铭 周瑞光 +5 位作者 尹代勋 高玉生 张福松 成彬芳 刘强 罗信华 《Science China Earth Sciences》 SCIE EI CAS 2003年第6期547-560,共14页
In the Yutianbao Mine, the Nantong Coal Field, Chongqing, a lot of gas samples were measured and analyzed. It has been found in these samples that helium is sensitive to stress concentration, while argon is sensitive ... In the Yutianbao Mine, the Nantong Coal Field, Chongqing, a lot of gas samples were measured and analyzed. It has been found in these samples that helium is sensitive to stress concentration, while argon is sensitive to stress release. Compared with the flowing out of gas it-self, the combination of helium and argon can be more suitably used as an indicator to predict gas outburst. In a mining area of this mine, both d He > 30 and d Ar < -0.97 can be used critically to define the dangerous area. Also, the contour maps of d He, d Ar and CH4 can provide a guidance for engineering monitoring. 展开更多
关键词 helium ARGON and its isotope STRESS emanation prediction of gas outburst contour map engineering geology.
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