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81.
Glioblastoma (GBM) is the most common malignant brain tumor and its malignant phenotypic characteristics are classified as grade IV tumors. Molecular interactions, such as protein–protein, protein–ncRNA, and protein–peptide interactions are crucial to transfer the signaling communications in cellular signaling pathways. Evidences suggest that signaling pathways of stem cells are also activated, which helps the propagation of GBM. Hence, it is important to identify a common signaling pathway that could be visible from multiple GBM gene expression data. microRNA signaling is considered important in GBM signaling, which needs further validation. We performed a high-throughput analysis using micro array expression profiles from 574 samples to explore the role of non-coding RNAs in the disease progression and unique signaling communication in GBM. A series of computational methods involving miRNA expression, gene ontology (GO) based gene enrichment, pathway mapping, and annotation from metabolic pathways databases, and network analysis were used for the analysis. Our study revealed the physiological roles of many known and novel miRNAs in cancer signaling, especially concerning signaling in cancer progression and proliferation. Overall, the results revealed a strong connection with stress induced senescence, significant miRNA targets for cell cycle arrest, and many common signaling pathways to GBM in the network.  相似文献   
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The influence of milk fat on physico‐chemical properties of calcium and vitamin D‐fortified milk was investigated. Sensory scores, curd tension, viscosity, rennet coagulation time and TBA value increased with the increase in fat content. Calcium and vitamin D fortification had no effect on sensory scores, whereas a significant increase was observed in curd tension and viscosity. The TBA value of fortified milk was significantly lower than that of the unfortified milk. The rennet coagulation time of milk increased significantly with addition of calcium phosphate, whereas calcium citrate fortification had no significant effect. All milk samples were stable to alcohol.  相似文献   
85.
Under heavy traffic conditions, some fatigue cracks have been found at welding joints between U-shaped ribs “trough ribs” and deck plates. Fatigue cracks along thickness direction of deck plate from root tip are important because visual crack detection from outside is limited. In this paper, new functional steel plates with initiation resistance of fatigue crack at weldment and propagation resistance at base material are applied to deck plate to evaluate improvement of fatigue life. We conducted fixed-point fatigue tests with real scale partial models consisted with one trough rib and a transverse girder, and the elastic FEM (Finite Element Method) analysis corresponding to the fatigue test specimen. Based on these results, we studied the fatigue properties which focused on the difference between conventional steel plates and newly developed steel plates, FCA (Fatigue Crack Arrester). Fatigue cracks were initiated from root tip of welded joints between a trough rib and a deck plate. It is clarified that FCA steel plates instead of conventional steel plates can improve the fatigue life under the same welding conditions. This improvement effect becomes much clearer in the high cycle region, which is noticeable at the operation and management stage of bridges.  相似文献   
86.
This paper proposes a spectrum sharing technique for coexistence of multiband orthogonal frequency division multiplexing ultra wideband (UWB) system with other primary wireless services. Existing technique like tone nulling do not utilize subcarriers within victim band, hence affects the throughput of the system. The same nulling effect can be produced by applying antiphase tones across transmitting antennas and simultaneously utilizing the victim band to transmit the data. This scheme can be applied without any impact on the current specifications of the system. In this paper complex orthogonal space time frequency code is implemented to achieve diversity in multiple antenna system. UWB receiver processing is described for both victim and unprotected band. A less computationally complex active interference cancellation scheme is also applied to improve notch depth. The proposed scheme is implemented for fixed frequency interleaving operation and discussed for time frequency interleaving with special cases. The proposed scheme is very simple to implement and provide flexibility in terms of notch width and depth.  相似文献   
87.
Interaction of molecular hydrogen with Be and Be2 decorated acetylene is studied using first principles calculations and molecular dynamics simulations. C2H2Be and C2H2Be2 complex can interact with maximum of two and four H2 molecules respectively thereby showing respective H2 uptake capacity of 10.3 and 15.5 wt % and is well above the target set by U.S. department of energy. Temperature dependent Gibbs free energy corrected adsorption energy shows that H2 adsorption on C2H2Be is energetically favorable below 250 and 200 K and 1 atm. pressure at MP2/6-311++G** and CCSD(T)/6-311++G** level whereas it is energetically favorable on C2H2Be2 at entire temperature and pressure range considered here from 50 K to 400 K and 50 atm to 400 atm. The desorption temperature obtained for C2H2Be(2H2) and C2H2Be2(4H2) complexes at MP2/6-311++G** level using van't Hoff equation is 281 and 638 K respectively. Molecular dynamics simulations performed at different temperature show that all the adsorbed H2 molecules remain adsorbed during the simulations on a complex at temperature T only if Gibbs free energy corrected H2 adsorption energy at that temperature T is positive. H2 adsorption on Be decorated ethylene is also studied and the results are compared with Be decorated acetylene.  相似文献   
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We have previously reported that in the well-differentiated beta-cell line MIN6 cells, the beta-cell-specific differentiated characteristics, such as insulin content, expression of prohormone convertases PC2 and PC3, and glucose-regulated insulin secretion, diminished when the proprotein-processing endoprotease furin was highly expressed. Since furin converts many growth-related protein precursors to their bioactive forms, we compared the four pancreatic islet cell lines RINm5F, betaTC3, betaHC9, and MIN6 with respect to cell growth rate, furin expression, endoprotease activity, and insulin content. RINm5F cells exhibited the strongest furin expression, higher furin-type endoprotease activity, and the fastest cell growth, but had the least insulin content. In contrast, MIN6 cells exhibited only a weak furin expression, little furin-type endoprotease activity, and the slowest cell growth, but had the highest insulin content. To test whether furin-expressing cells secrete growth-promoting factors cleaved by furin, we prepared conditioned media from RINm5F and furin cDNA-introduced MIN6 (MIN6-F) cells. The conditioned media from RINm5F and MIN6-F induced increased DNA synthesis and promoted the growth of normal MIN6 cells, compared with the medium from the empty vector-introduced MIN6-0 cells. We then examined the effect of the protease inhibitors alpha1-antitrypsin and its variants by infecting their vaccinia recombinants to the four cell lines. All conditioned media from each cell line expressing the furin-specific alpha1-antitrypsin variant exhibited the least DNA synthetic capacity on normal MIN6 cells. Furthermore, all three sublines of MIN6-F grew faster than MIN6-0 and MIN6. Thus, we suggest that the islet cells with higher furin expression may induce increased production of growth factors, which result in an increase in cell growth, through an autocrine/paracrine mechanism.  相似文献   
90.
Gray codes are useful in the minimization of digital errors due to an ambiguous analog signal between two adjacent levels. The weight structure in coding has its own significance. In this paper, we study the weight structure of the binary Gray code Gn(0) and extend the result for nonbinary Gray codes Gm:n(0). With our study it is possible to find the weight of a codeword occupying a given place in the codebook.  相似文献   
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