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51.
Matthieu Maitre Minh N. Do 《Journal of Visual Communication and Image Representation》2010,21(5-6):513-522
We present a novel depth and depth–color codec aimed at free-viewpoint 3D-TV. The proposed codec uses a shape-adaptive wavelet transform and an explicit encoding of the locations of major depth edges. Unlike the standard wavelet transform, the shape-adaptive transform generates small wavelet coefficients along depth edges, which greatly reduces the bits required to represent the data. The wavelet transform is implemented by shape-adaptive lifting, which enables fast computations and perfect reconstruction. We derive a simple extension of typical boundary extrapolation methods for lifting schemes to obtain as many vanishing moments near boundaries as away from them. We also develop a novel rate-constrained edge detection algorithm, which integrates the idea of significance bitplanes into the Canny edge detector. Together with a simple chain code, it provides an efficient way to extract and encode edges. Experimental results on synthetic and real data confirm the effectiveness of the proposed codec, with PSNR gains of more than 5 dB for depth images and significantly better visual quality for synthesized novel view images. 相似文献
52.
K. Mayolo‐Deloisa C. Machín‐Ramírez M. Rito‐Palomares M. R. Trejo‐Hernández 《化学工程与技术》2011,34(8):1368-1372
Laccase partially purified from residual compost of Agaricus bisporus by an aqueous two‐phase system (Lac ATPS) was used in degrading polycyclic aromatic hydrocarbons: fluorene (Flu), phenanthrene (Phe), anthracene (Ant), benzo[a]pyrene (BaP), and benzo[a]anthracene (BaA). The capacity of the enzyme to oxidize polyaromatic compounds was compared to that of the crude laccase extract (CE). After treatment of 72 h, Lac ATPS and CE were not capable of oxidizing Flu and Phe, while Ant, BaP, and BaA were oxidized, resulting in percentages of oxidation of 11.2 ± 1, 26 ± 2, and 11.7 ± 4 % with CE, respectively. When Lac ATPS was used, the following percentages of oxidation were obtained: 11.4 ± 3 % for Ant, 34 ± 0.1 % for BaP, and 13.6 ± 2 % for BaA. The results reported here demonstrate the potential application of Lac ATPS for the oxidation of polycyclic aromatic hydrocarbons. 相似文献
53.
Eunyoung Lee Michelle Novais de Paula Sangki Baek Huynh Kim Khanh Ta Minh Tan Nguyen Taeck-Hyun Jeong Chong Jai Kim Yeon Jin Jang Han Choe 《International journal of molecular sciences》2021,22(12)
Human stem-cell factor (hSCF) stimulates the survival, proliferation, and differentiation of hematopoietic cells by binding to the c-Kit receptor. Various applications of hSCF require the efficient and reliable production of hSCF. hSCF exists in three forms: as two membrane-spanning proteins hSCF248 and hSCF229 and truncated soluble N-terminal protein hSCF164. hSCF164 is known to be insoluble when expressed in Escherichia coli cytoplasm, requiring a complex refolding procedure. The activity of hSCF248 has never been studied. Here, we investigated novel production methods for recombinant hSCF164 and hSCF248 without the refolding process. To increase the solubility of hSCF164, maltose-binding protein (MBP) and protein disulfide isomerase b’a’ domain (PDIb’a’) tags were attached to the N-terminus of hSCF164. These fusion proteins were overexpressed in soluble form in the Origami 2(DE3) E. coli strain. These solubilization effects were enhanced at a low temperature. His-hSCF248, the poly-His tagged form of hSCF248, was expressed in a highly soluble form without a solubilization tag protein, which was unexpected because His-hSCF248 contains a transmembrane domain. hSCF164 was purified using affinity and ion-exchange chromatography, and His-hSCF248 was purified by ion-exchange and gel filtration chromatography. The purified proteins stimulated the proliferation of TF-1 cells. Interestingly, the EC50 value of His-hSCF248 was 1 pg/mL, 100-fold lower than 9 ng/mL hSCF164. Additionally, His-hSCF248 decreased the doubling time, increased the proportion of S and G2/M stages in the cell cycle, and increased the c-Myc expression at a 1000-fold lower concentration than hSCF164. In conclusion, His-hSCF248 was expressed in a soluble form in E. coli and had stronger activity than hSCF164. The molecular chaperone, MBP, enabled the soluble overexpression of hSCF164. 相似文献
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55.
F. Mach und M. Fischler 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1922,43(6):256-261
Ohne ZusammenfassungMitteilung der Staatlichen Landwirtschaftlichen Versuchsanstalt Augustenberg.Vergl. Diese Zeitschrift 1921,42, 35. 相似文献
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57.
V. A. Glazunov S. Briot V. Arakelyan M. M. Gruntovich Ngyuen Minh Thanh 《Journal of Machinery Manufacture and Reliability》2008,37(2):176-185
Manipulators of a new class characterized by a parallel-cross structure are considered. Kinematic chains located according to the principles of a parallel structure are linked with cross chains that contain drives or impose constraints. Such a layout may facilitate a decrease in the dimensions of the foundation and the output link and an increase in stiffness. A classification of the proposed mechanisms is presented. The working volumes of the new manipulators and those of the most popular manipulators based on a parallel structure (the Gough-Stewart platform) are compared. 相似文献
58.
Hoa Le Minh O'Brien D. Faulkner G. Lubin Zeng Kyungwoo Lee Daekwang Jung YunJe Oh 《Photonics Technology Letters, IEEE》2008,20(14):1243-1245
White light-emitting diodes (LEDs) are becoming widespread in commercial lighting applications, and there are predictions that they will be in common use in domestic applications in the future. There is also growing interest in using these devices for both illumination and communications. One of the major challenges in visible light communications is the low modulation bandwidth (BW) available from devices, which is typically several megahertz. In this letter, we describe a link that uses 16 LEDs which are modulated using a resonant driving technique, creating an overall BW of 25 MHz. This is used to implement a 40-Mb/s nonreturn-to-zero on-off keying link which operates at low error rates, and also provides illumination at levels sufficient for a standard office environment. 相似文献
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60.
Phuong Pham Thi Thuy Phuong Nguyen Nguyen Kumar P. Senthil Duy Nguyen Phuc Hoang Van Le Quyet Ngoc Le Thi Bao Jalil A. A. Rajendran Saravanan Cheng Chin Kui Nguyen Thanh-Huong Dinh Minh Tuan Nguyen Vo Dai-Viet N. 《Topics in Catalysis》2023,66(1-4):41-52
Topics in Catalysis - CO2 reforming of methanol for producing hydrogen was experimentally carried out in a fixed-bed reactor on 10%Ni/SiO2. The 10%Ni/SiO2 was completely reduced during H2... 相似文献