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81.
82.
The human oncoprotein p13MTCP1 is coded by the MTCP1 gene, a gene involved in chromosomal translocations associated with T-cell prolymphocytic leukemia, a rare form of human leukemia with a mature T-cell phenotype. The primary sequence of p13MTCP1 is highly and only homologous to that of p14TCL1, a product coded by the gene TCL1 which is also involved in T-cell prolymphocytic leukemia. These two proteins probably represent the first members of a new family of oncogenic proteins. We present the three-dimensional solution structure of the recombinant p13MTCP1 determined by homonuclear proton two-dimensional NMR methods at 600 MHz. After proton resonance assignments, a total of 1253 distance restraints and 64 dihedral restraints were collected. The solution structure of p13MTCP1 is presented as a set of 20 DYANA structures. The rmsd values with respect to the mean structure for the backbone and all heavy atoms for the conformer family are 1.07 +/- 0.19 and 1.71 +/- 0.17 A, when the structured core of the protein (residues 11-103) is considered. The solution structure of p13MTCP1 consists of an orthogonal beta-barrel, composed of eight antiparallel beta-strands which present an original arrangement. The two beta-pleated loops which emerge from this barrel might constitute the interaction surface with a potential molecular partner.  相似文献   
83.
One of the important issues of green mobile networking is the low energy consumption for either mobile devices or transmissions. To adapt this, a low-cost Inter frame mode decision (MD) algorithm is proposed for H.264/AVC encoder to reduce the computational complexity of the original encoding procedure in this paper. The information extracted from macroblock (MB), such as energy, temporal domain mode similarity and so on, which can be used to pre-estimate the optimal mode of the MB is investigated and utilized to eliminate the redundant mode candidates. The performance evaluations including quantitative analysis and PC simulations show that the proposed algorithm is an energy-efficient source coding because it can reduce around 85% Inter frame encoding time with little quality loss. It can be widely implemented in green mobile networking systems with H.264/AVC standard to realize the real-time video signal coding.  相似文献   
84.
We present a novel, to our knowledge, fiber-based single-channel polarization-sensitive spectral interferometry system that provides depth-resolved measurement of polarization transformations of light reflected from a sample. Algebraic expressions for the Stokes parameters at the output of the interferometer are derived for light reflected from a birefringent sample by using the cross-spectral density function. By insertion of a fiber-optic spectral polarimetry instrument into the detection path of a common-path spectral interferometer, the full set of Stokes parameters of light reflected from a sample can be obtained with a single optical frequency scan. The methodology requires neither polarization-control components nor prior knowledge of the polarization state of light incident on the sample. The fiber-based single-channel polarization-sensitive spectral interferometer and analysis are demonstrated by measurement of phase retardation and fast-axis angle of a birefringent mica plate.  相似文献   
85.
The composition of amorphous oxide semiconductors, which are well known for their optical transparency, can be tailored to enhance their absorption and induce photoconductivity for irradiation with green, and shorter wavelength light. In principle, amorphous oxide semiconductor-based thin-film photoconductors could hence be applied as photosensors. However, their photoconductivity persists for hours after illumination has been removed, which severely degrades the response time and the frame rate of oxide-based sensor arrays. We have solved the problem of persistent photoconductivity (PPC) by developing a gated amorphous oxide semiconductor photo thin-film transistor (photo-TFT) that can provide direct control over the position of the Fermi level in the active layer. Applying a short-duration (10 ns) voltage pulse to these devices induces electron accumulation and accelerates their recombination with ionized oxygen vacancy sites, which are thought to cause PPC. We have integrated these photo-TFTs in a transparent active-matrix photosensor array that can be operated at high frame rates and that has potential applications in contact-free interactive displays.  相似文献   
86.
When a force is applied tangentially on the main axis of beam-type structure, it is well known that the system becomes non-conservative. Dynamic instability of tube excited by moving follower force discretely and periodically is investigated. The effective stiffness of system becomes non-stationary due to time-dependent follower force. Floquet theory is employed to examine the heteroparametric instability regions in the system parameter space. It turns out that there exist two type of instability that are due to parametric and combination resonances, which are confirmed through numerical simulation. Unique features which occur in parametric vibration are also discussed.  相似文献   
87.
In this letter, we investigated the effects of source/drain series resistance on amorphous gallium-indium-doped zinc-oxide (a-GIZO) thin film transistors (TFTs). A linear least square fit of a plot of the reciprocal of channel resistance versus gate voltage yields a threshold voltage of 3.5 V and a field-effect mobility of about 13.5 cm2/Vldrs. Furthermore, in a-GIZO TFTs, most of the current flows in the distance range of 0-0.5 mum from the channel edge and shorter than that in a-Si:H TFTs. Moreover, unlike a-Si:H TFTs, a-GIZO TFTs did not show an intersection point, because they did not contain a highly doped ohmic (n+) layer below the source/drain electrodes.  相似文献   
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LIX 34 liquid ion exchange reagent was introduced commercially by General Mills in 1976. The fundamental aspects of lead extraction and stripping using LIX 34 as the organic extractant in acetic solution has been studied here. Equilibrium isotherms for extraction and stripping, isothermal pH effects, temperature effect, loading capacity and the rate of extraction and stripping on the system Pb2+-HAc-LIX 34—Kermac 470B are reported.  相似文献   
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