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61.
Sachi Oshima Shunichi Asai Naohiko Seki Chikashi Minemura Takashi Kinoshita Yusuke Goto Naoko Kikkawa Shogo Moriya Atsushi Kasamatsu Toyoyuki Hanazawa Katsuhiro Uzawa 《International journal of molecular sciences》2021,22(12)
We identified the microRNA (miRNA) expression signature of head and neck squamous cell carcinoma (HNSCC) tissues by RNA sequencing, in which 168 miRNAs were significantly upregulated, including both strands of the miR-31 duplex (miR-31-5p and miR-31-3p). The aims of this study were to identify networks of tumor suppressor genes regulated by miR-31-5p and miR-31-3p in HNSCC cells. Our functional assays showed that inhibition of miR-31-5p and miR-31-3p attenuated cancer cell malignant phenotypes (cell proliferation, migration, and invasion), suggesting that they had oncogenic potential in HNSCC cells. Our in silico analysis revealed 146 genes regulated by miR-31 in HNSCC cells. Among these targets, the low expression of seven genes (miR-31-5p targets: CACNB2 and IL34; miR-31-3p targets: CGNL1, CNTN3, GAS7, HOPX, and PBX1) was closely associated with poor prognosis in HNSCC. According to multivariate Cox regression analyses, the expression levels of five of those genes (CACNB2: p = 0.0189; IL34: p = 0.0425; CGNL1: p = 0.0014; CNTN3: p = 0.0304; and GAS7: p = 0.0412) were independent prognostic factors in patients with HNSCC. Our miRNA signature and miRNA-based approach will provide new insights into the molecular pathogenesis of HNSCC. 相似文献
62.
While reuse is an effective lifecycle option in terms of reduction of environmental loads and value of reutilization, reuse has inherent difficulties. Our naive question is why component reuse of home appliances seems impossible while that of photocopiers succeeded. This paper clarifies an essential factor for successful reuse; that is, the balance between supply and demand of reusables, and proposes an index named ‘marginal reuse rate,’ which indicates upper limit of reusability. By using this index, reusability of several products is analyzed. The marginal reuse rate indicates that design of lifecycle, in addition to product design, is indispensable for successful reuse. 相似文献
63.
Yttria (Y2O3) films were prepared at high deposition rates of up to 83 nm/s (300 μm/h) by laser chemical vapor deposition (LCVD) using an Y(dpm)3 precursor. The effects of deposition conditions, mainly total gas pressure and laser power, on morphology, deposition rate and preferred orientation were studied. Plasma was produced around the substrate over a critical laser power resulting in significant increases in deposition temperature and deposition rate. The high deposition rate (300 μm/h) by LCVD was about 100 to 1000 times as high as those by conventional CVD. The morphology of Y2O3 films changed from faceted and columnar structures with high (400) orientation to a columnar structure with high (440) orientation, and finally to a cone-like structure with moderate (440) orientation with increasing total gas pressure (Ptot). 相似文献
64.
A New Process to Make a Porous PTFE Structure from Aqueous PTFE Dispersion with the Help of Hydrogel
A novel method to make a porous material having relatively large cell diameter (200–300 m), which consisted of mainly poly(tetrafluoroethylene) (PTFE), was developed from aqueous PTFE dispersion by using the characteristics of hydrogel with the addition of carbon nanofiber (CNF). The porous material was produced as follows: firstly, an aqueous agar gel containing PTFE and CNF was prepared; secondly, the gel was freeze-dried; thirdly, the dried gel was heat-treated at 400°C where the agar was almost decomposed and PTFE became molten. The porous material showed electric conductivity (about 50 ), high porosity (about 96 vol%), and relatively uniform cell structures without shrinkage during freeze drying and heat treatment. While the method without CNF resulted in large shrinkage during heat treatment, meaning that CNF prevented the shrinkage. It was explained by the idea that the existence of rigid CNF, which was dispersed in the cell wall, prohibited the shrinkage of PTFE during heat treatment. It was unexpectedly found by SEM analysis that the porous materials had another macro-porous structure inside the cell wall, suggesting that the developed materials had a double porous structure. 相似文献
65.
Chemiluminescence (CL) analysis was used for determining the oxidation layer formed by the irradiation of polypropylene for medical supplies. The depth of the oxidation layer from the surface depended on dose rate and increased with decreasing dose rate. The oxidation occurred remarkably at a region near the surface area of the film where the diffusion of oxygen is more sufficient. On the contrary, there was very little oxidation in the interior portion. The oxidation layers of polypropylene samples irradiated with electron beam showed U-shaped profiles in the cross-section of film as did as a sample irradiated with γ-rays. However, the degree of oxidation by irradiation with electron beam was very small; CL intensity at the surface area was only one-third that for the γ-irradiated samples. 相似文献
66.
α,β,β-Trifluoroethylenesulfonyl fluoride (TFESF) was grafted onto polyethylene (PE) film by a simultaneous-irradiation method. The influences of the grafting conditions were analyzed kinetically. The dependencies of the grafting rate on the dose rates and monomer concentrations ranging from 10 to 75% were found to be of 1 and 0 order, respectively. The overall activation energy for the graft polymerization was 2.05 × 104 J/mol. The grafting rate was found to be independent of the film thicknesses ranging from 25 to 100 μm. 相似文献
67.
The effect of particle agglomeration on sintering has been studied by slipcasting suspensions with pH values ranging from 2 to 11. The rate of densification has been found to depend on the degree of agglomeration. Complete dispersion of alumina primary particles has not been attained through adjustment of pH of suspensions, and agglomerates also remained in the best-dispersed suspension. Elimination of the agglomerates by sedimentation lowered the densification temperature of slip-cast compacts. The grain size-density curve is a function of temperature. High-density and small-grained sintered bodies were obtained by low-temperature long-time firing. 相似文献
68.
Koki Murano Tomoyoshi Shimobaba Atsushi Sugiyama Naoki Takada Takashi Kakue Minoru Oikawa Tomoyoshi Ito 《Computer Physics Communications》2014
We report fast computation of computer-generated holograms (CGHs) using Xeon Phi coprocessors, which have massively x86-based processors on one chip, recently released by Intel. CGHs can generate arbitrary light wavefronts, and therefore, are promising technology for many applications: for example, three-dimensional displays, diffractive optical elements, and the generation of arbitrary beams. CGHs incur enormous computational cost. In this paper, we describe the implementations of several CGH generating algorithms on the Xeon Phi, and the comparisons in terms of the performance and the ease of programming between the Xeon Phi, a CPU and graphics processing unit (GPU). 相似文献
69.
Given a directed or undirected graph G=(V,E), a collection ${\mathcal{R}}=\{(S_{i},T_{i}) \mid i=1,2,\ldots,|{\mathcal{R}}|, S_{i},T_{i} \subseteq V, S_{i} \cap T_{i} =\emptyset\}$ of two disjoint subsets of V, and a requirement function $r: {\mathcal{R}} \to\mathbb{R}_{+}$ , we consider the problem (called area-to-area edge-connectivity augmentation problem) of augmenting G by a smallest number of new edges so that the resulting graph $\hat{G}$ satisfies $d_{\hat{G}}(X)\geq r(S,T)$ for all X?V, $(S,T) \in{\mathcal{R}}$ with S?X?V?T, where d G (X) denotes the degree of a vertex set X in G. This problem can be regarded as a natural generalization of the global, local, and node-to-area edge-connectivity augmentation problems. In this paper, we show that there exists a constant c such that the problem is inapproximable within a ratio of $c\log{|{\mathcal{R}}|}$ , unless P=NP, even restricted to the directed global node-to-area edge-connectivity augmentation or undirected local node-to-area edge-connectivity augmentation. We also provide an ${\mathrm{O}}(\log{|{\mathcal{R}}|})$ -approximation algorithm for the area-to-area edge-connectivity augmentation problem, which is a natural extension of Kortsarz and Nutov’s algorithm (Kortsarz and Nutov, J. Comput. Syst. Sci., 74:662–670, 2008). This together with the negative result implies that the problem is ${\varTheta}(\log{|{\mathcal{R}}|})$ -approximable, unless P=NP, which solves open problems for node-to-area edge-connectivity augmentation in Ishii et al. (Algorithmica, 56:413–436, 2010), Ishii and Hagiwara (Discrete Appl. Math., 154:2307–2329, 2006), Miwa and Ito (J. Oper. Res. Soc. Jpn., 47:224–243, 2004). Furthermore, we characterize the node-to-area and area-to-area edge-connectivity augmentation problems as the augmentation problems with modulotone and k-modulotone functions. 相似文献
70.
Schaefer-Sindlinger A. Lappas I. Vogt C. D. Ito T. Kurachi H. Makino M. Takahashi A. 《Topics in Catalysis》2007,42(1-4):307-317
This paper will give an overview about the filter development for diesel particulate emission control in automotive applications.
The material development for passenger car diesel particulate filters led to new materials like silicon carbide while for
heavy duty applications still Cordierite plays a major role. But in the future other materials might also be used for passenger
cars. This paper will show the basic difference between both applications and describe the material design in terms of filter
properties (base material, back pressure aspects, filtration efficiency, coating impact). Current application on vehicles
with catalysed soot filters (CSF) with and without oxidation catalyst will be presented. Furthermore an outlook will be given
on materials for catalysed soot filters for the future. 相似文献