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41.
Mosca A Paleari R Galanello R Sollaino C Perseu L Demartis FR Passarello C Giambona A Maggio A;IFCC Working Group on Standardization of HbA 《Bioelectrochemistry (Amsterdam, Netherlands)》2008,73(2):137-140
The increase of HbA(2) is the most important feature in the identification of beta-thalassemia carriers. However, some carriers are difficult to identify, because the level of HbA(2) is not in the typical range. Few data are available concerning the prevalence of such unusual phenotypes, and knowing their expected prevalence could be helpful in detecting systematic drifts in the analytical systems for HbA(2) quantification. In this study we report a retrospective investigation in two centres with high prevalence of beta-thalassemia. The prevalence of borderline subjects was found to be 2.2 and 3.0%, respectively. The genotypes of a subgroup of these subjects were then analyzed and in about 25% of cases a mutation in the globin genes was identified. We conclude that the occurrence of HbA(2) borderline phenotypes is not a rare event. In order to obtain more accurate HbA(2) measurements the development of an international reference measurement system for HbA(2), based on quantitative peptide mapping, has been recently started. We believe that the innovative approach of our method could also be used as a model to develop accurate quantitative methods for other red cell proteins relevant to the biodynamic properties and the surface electrochemistry of erythrocytes. 相似文献
42.
Ernian Pan 《Acta Mechanica Solida Sinica》2011,24(1):83-91
In this paper,a three-dimensional finite-element formulation for the multiferroic composite is developed and implemented into the commercial software ABAQUS for its transient analysis.First,a special three-dimensional eight-node solid element is designed to handle the multiferroic composite made of elastic,piezoelectric,and piezomagnetic materials.Second,a userdefined subroutine for this newly developed element is implemented into ABAQUS.Finally,the transient responses of a bi-layered multiferroic composite are calculated by using the direct time integration method.Two typical magnetic potential signals,Gauss and Ricker pulses,are applied to the composite with various time durations of excitation.The induced electric field shows that the transient response can be substantially influenced by the input signal,which could be tuned for the strongest electric output. 相似文献
43.
Bhanudas Naik Vilas Desai Meenal Kowshik Vadakkethonippurathu Sivankutty Prasad Gerard Franklyn Fernando Narendra Nath Ghosh 《中国颗粒学报》2011,(3)
Simple aqueous solution-based chemical methods have been developed for the synthesis of Ag/AgCl nanoparticle-mesoporous silica nanocomposites. Ag loading in the mesoporous silica was accomplished using a wet-impregnation method. The AgCl-mesoporous silica nanocomposite material(AgCl-mSi) was synthesized by using a 'one pot' method. Synthesized materials were characterized using X-ray diffraction,N2 adsorption-desorption analysis and high-resolution transmission electron microscopy. Antibacterial activity of... 相似文献
44.
In this article, linear regular index 2 DAEs A(t)[D(t)x(t)]′+B(t)x(t)=q(t) are considered. Using a decoupling technique, initial condition and boundary condition are properly formulated. Regular index 1 DAEs are obtained by a regularization method. We study the behavior of the solution of the regularization system via asymptotic expansions. The error analysis between the solutions of the DAEs and its regularization system is given. 相似文献
45.
Cho T Kohagura J Numakura T Hirata M Higaki H Hojo H Ichimura M Ishii K Islam KM Itakura A Katanuma I Minami R Nakashima Y Saito T Tatematsu Y Watanabe O Yoshikawa M Kojima A Miyake Y Miyata Y Shimizu K Tomii Y Yoshida M Sakamoto K Imai T Pastukhov VP Miyoshi S;GAMMA Group 《Physical review letters》2006,97(5):055001
Off-axis electron-cyclotron heating in an axisymmetric barrier mirror produces a cylindrical layer with energetic electrons, which flow through the central cell and into the end region. The layer, producing a localized bumped ambipolar potential Phi(C), forms a strong shear of radial electric fields E(r) and peaked vorticity with the direction reversal of E(r)xB sheared flow near the Phi(C) peak. Intermittent vortexlike turbulent structures near the layer are suppressed in the central cell by this actively produced transverse energy-transport barrier; this results in T(e) and T(i) rises surrounded by the layer. 相似文献
46.
LIANG LiFu LIU ShiQuan &ZHOU JianSheng School of Civil Engineering Harbin Engineering University Harbin China China Sanjiang Space Industry Group Corp Wuhan 《中国科学G辑(英文版)》2009,52(5):775-787
The reasons for studying single flexible body dynamics are that on one hand, it is the basis of flexible multi-body dynamics.
If the theory of the single flexible body dynamics has been deeply studied, the theory of flexible multi-body dynamics will
be researched easily. On the other hand, it has its unique and important applications. Quasi-variational principle of non-conservative
single flexible body dynamics is established under the cross-link of particle rigid body mechanics and deformable body mechanics.
Taking the interceptor as an example, this paper has explained the physical meaning of the quasi-stationary value condition
of the quasi-variational principle in non-conservative single flexible body dynamics. Taking the launch of rocket as an example,
it has illustrated the features of “one force for two effects” in a single flexible body dynamics. With an example of the
extending flexible beam coupled with the spacecraft attitude, it has shown the transition from the single flexible body dynamics
to the flexible multi-body dynamics. Finally, a number of related problems are discussed.
Supported by the National Natural Science Foundation of China (Grant No. 10272034), the Doctoral Education Foundation (Grant
No. 20060217020), and the Natural Science Foundation of Harbin Engineering University (Grant No. HEUF04003) 相似文献
47.
杭州大学弱智儿童问题研究组 《浙江大学学报(理学版)》1987,14(3):362-370
为了能对弱智儿童智力缺损的程度作出较好的鉴别和帮助矫治起见,编制了一份适用于浙江省的儿童智力量表。本文讨论量表内容的选择和确定。 研究过程与方法:以两套不同内容的材料(共71题),先后分两次对31名小学一年级7岁儿童和28名弱智学校儿童(7—13岁)进行个别测试。根据测试结果的分析和比较,最后选定42题,编排为10个分测验,作为本量表的内容。它们是:1)图画填充;2)照管日常生活;3)实物排列;4)计算;5)图片归类;6)分辨能力;7)拼积木;8)数字背诵;9)划去图形;10)理解。 相似文献
48.
The Buenos Aires Cyclic Homology Group 《K-Theory》1991,5(1):51-69
We compute the cyclic homology of A = k[X]/X
n for an arbitrary commutative ring k, and we apply this result to compute the cyclic homology of k[X]/f, when k is a field and f is an arbitrary polynomial.This work was presented at the IX-ELAM, Santigo de Chile, July 1988, and was partially supported by CONICET.The following pepole participated in this research: Jorge A. Guccione, juan José guccione, Maria Julia Redondo, Andrea Solotar, and Orlando E. Villamayor. 相似文献
49.
Krishnan A Liu YH Cha P Woodward R Allara D Vogler EA;Hematology at Biomaterial Interfaces Research Group 《Colloids and surfaces. B, Biointerfaces》2005,43(2):95-98
A systematic comparison of Wilhelmy-balance tensiometry (WBT), tilting-plate goniometry (TPG) and captive-drop goniometry (CDG), using a variety of silane-treated glass surfaces of variable wetting characteristics is reported. WBT was assumed to be the benchmark of comparison (gold standard). Advancing angles measured by TPG and CDG were in statistical agreement with corresponding WBT measurements. In contrast, receding angles from both goniometric techniques were systematically higher than WBT. 相似文献
50.
Lewis JK Rudzinsky J Rajan S Stein PJ Vandiver A;KauaiEx Group 《The Journal of the Acoustical Society of America》2005,117(6):3539-3554
A tomographic scheme is presented that ingests ocean acoustic measurements into an ocean model using data from bottom-mounted hydrophones. The short distances between source-receiver pairs (1-10 km) means arrival times at frequencies of 8-11 kHz are readily detectable and often distinguishable. The influence of ocean surface motion causes considerable variability in acoustic travel times. Techniques are presented for measuring travel times and removing the variability due to surface waves. An assimilation technique is investigated that uses differences in measured and modeled acoustic travel times to impose corrections on the oceanographic model. Equations relating travel time differences to oceanographic variables are derived, and techniques are presented for estimating the acoustic and ocean model error covariance matrices. One test case using a single source-receiver pair shows that the tomographic information can have an impact on constraining the solution of the ocean circulation model but can also introduce biases in the predictions. A second test case utilizes knowledge of a bias in a model-predicted variable to limit grid cells that are impacted by the tomographic data. In this case, using the tomographic data results in significant improvements in the model predictions without introducing any biases. 相似文献