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991.
G Wu T Mochizuki TC Le Y Cai T Hayashi DM Reynolds S Somlo 《Canadian Metallurgical Quarterly》1997,45(1):220-223
The gene responsible for the second form of autosomal dominant polycystic kidney disease, PKD2, has recently been identified. We now describe the cloning, genomic localization, cDNA sequence, and expression analysis of its murine homologue, Pkd2. The cloned cDNA sequence is 5134 bp long and is predicted to encode a 966-amino-acid integral membrane protein with six membrane-spanning domains and intracellular NH2 and COOH termini. Pkd2 is highly conserved with 91% identity and 98% similarity to polycystin-2 at the amino acid level. Pkd2 mRNA is widely expressed in mouse tissues. Pkd2 maps to mouse Chromosome 5 and is excluded as a candidate gene for previously mapped mouse mutations resulting in a polycystic kidney phenotype. 相似文献
992.
MR Gillmore EA Wells EE Simpson DM Morrison MJ Hoppe A Wilsdon 《Canadian Metallurgical Quarterly》1998,24(1):131-151
This paper reports the results of a study in which age (grade level), racial/ethnic, and gender differences in beliefs and perceived norms about drinking were examined in a multi-ethnic urban sample of 4th through 7th grade children. Results showed that older children held beliefs and perceived norms that were more favorable toward drinking than younger children. The major difference between older and younger children lay in their differential estimates of the likelihood of certain consequences occurring and not in their evaluation of these consequences of drinking. Further, older children not only displayed less motivation to comply with their parents and greater motivation to comply with their peers, but they also perceived their parents, as well as their peers, as less disapproving of drinking than did younger children. There were few gender or race/ethnicity differences at these ages in children's beliefs and perceived norms about drinking. 相似文献
993.
994.
Dependence of the Ca2+-inhibitable adenylyl cyclase of C6-2B glioma cells on capacitative Ca2+ entry
The ability of adenylyl cyclases to be regulated by physiological transitions in Ca2+ provides a key point for integration of cytosolic Ca2+ concentration ([Ca2+]i) and cAMP signaling. Ca2+-sensitive adenylyl cyclases, whether endogenously or heterologously expressed, require Ca2+ entry for their regulation, rather than Ca2+ release from intracellular stores (Chiono, M., Mahey, R., Tate, G., and Cooper, D. M. F. (1995) J. Biol. Chem. 270, 1149-1155; Fagan, K., Mahey, R., and Cooper, D. M. F. (1996) J. Biol. Chem. 271, 12438-12444). The present study compared the regulation by capacitative Ca2+ entry versus ionophore-mediated Ca2+ entry of an endogenously expressed Ca2+-inhibitable adenylyl cyclase in C6-2B cells. Even in the face of a dramatic [Ca2+]i rise generated by ionophore, Ca2+ entry via capacitative Ca2+ entry channels was solely responsible for the regulation of the adenylyl cyclase. Selective efficacy of BAPTA over equal concentrations of EGTA in blunting the regulation of the cyclase by capacitative Ca2+ entry defined the intimacy between the adenylyl cyclase and the capacitative Ca2+ entry sites. This association could not be impaired by disruption of the cytoskeleton by a variety of strategies. These results not only establish an intimate spatial relationship between an endogenously expressed Ca2+-inhibitable adenylyl cyclase with capacitative Ca2+ entry sites but also provide a physiological role for capacitative Ca2+ entry other than store refilling. 相似文献
995.
996.
I. Uzun-Kaymak S. Messer R. Bomgardner A. Case R. Clary R. Ellis R. Elton A. Hassam C. Teodorescu D. Witherspoon W. Young 《Journal of Fusion Energy》2009,28(3):240-242
We present preliminary results of the High Density Plasma Injection Experiment at the Maryland Centrifugal Experiment (MCX).
HyperV Technologies Corp. has designed, built, and installed a prototype coaxial gun to drive rotation in MCX. This gun has
been designed to avoid the blow-by instability via a combination of electrode shaping and a tailored plasma armature. An array
of diagnostics indicates the gun is capable of plasma jets with a mass of 160 μg at 70 km/s with an average plasma density
above 1015 cm−3. Preliminary measurements are underway at MCX to understand the penetration of the plasma jet through the MCX magnetic field
and the momentum transfer from the jet to the MCX plasma. Data will be presented for a wide range of MCX field parameters,
and the prospects for future injection experiments will be evaluated. 相似文献
997.
Young Seok Han Min Kyu Park Chang Won Kim Moon Gi Kang 《International journal of imaging systems and technology》2006,16(3):92-102
Complementary color filter array (CCFA) is widely used in consumer‐level digital video cameras, since it not only has high sensitivity and good signal‐to‐noise ratio in low‐light condition but also is compatible with the interlaced scanning used in broadcast systems. However, the full‐color images obtained from CCFA suffer from the color artifacts such as false color and zipper effects. These artifacts can be removed with edge‐adaptive color interpolation (ECI) approaches which are generally used in primary color filter array (PCFA). Unfortunately, the unique array pattern of CCFA makes it difficult that CCFA adopts ECI approaches. Therefore, to apply ECI approaches suitable for CCFA to color interpolation is one of the major issues to reconstruct the full‐color images. In this paper, we propose a new ECI algorithm for CCFA. To estimate an edge direction precisely and enhance the quality of the reconstructed image, a function of spatial variances is used as a weight, and new color conversion matrices are presented for considering various edge directions. Experimental results indicate that the proposed algorithm outperforms the conventional method with respect to both objective and subjective criteria. © 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 16, 92–102, 2006 相似文献
998.
Core/Shell Ag/ZnO Nanochurros: An Optically Flat Conductive Outcoupler Using Core/Shell Ag/ZnO Nanochurros (Small 20/2018) 下载免费PDF全文
999.
Time-accurate viscous flow solutions are sought for the prediction of unsteady flow characteristics and associated aeroacoustic blade tonal noise of a cross flow fan. The two-dimensional incompressible Navier-Stokes equations in a moving coordinate are time-accurately solved by an unstructured finite-volume method on triangular meshes, and a sliding mesh technique is utilized at the interface between the domain rotating with blades and the stationary one for allowing the unsteady interactions. An accuracy assessment of the present method is made by comparing the fan performances with experimental data for a rotational speed at 1000 rpm and the Reynolds number 5300 based on blade tip speed and chord length. With the computed unsteady viscous flow solutions, sound pressure is predicted using Curle’s equation and narrow-band noise characteristics of three impellers with a uniform and two random pitch (type-A and -B) blades are compared by their sound pressure level spectra. Also, the frequency modulations of the blade passing frequency noise by random pitch fans are discussed. 相似文献
1000.
Application of a two-level optimization process to conceptual structural design of a machine tool 总被引:1,自引:0,他引:1
Bi-Chu Wu Gin-Shu Young Te-Yen Huang 《International Journal of Machine Tools and Manufacture》2000,40(6):783-794
This paper proposes a modified two-level optimization approach for the concept design of a machine tool. The lower level of optimization is applied to each structural part of the tool and the upper level to the machine tool as an integrated system. When frequent modification of design specifications is required and re-use of previous design experience is preferred, the proposed approach is efficient because of the approximation functions used. Examples presented in the paper show that the principal dimensions of all the structural parts can be determined, minimizing the weight of the machine while maintaining sufficient stiffness. 相似文献