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341.
342.
Silica-based planar lightwave circuits (PLCs) are playing key roles in both optical dense wavelength-division multiplexing networks and optical access networks. This paper provides an outline of PLC technology focusing on passive devices such as arrayed waveguide grating multiplexers 相似文献
343.
Since Bcl-2 protects a variety of cell types from programmed cell death, whereas Bax promotes apoptosis, the present study examines Bcl-2 and Bax proteins, and bcl-2 and bax mRNA expression in the developing cerebellum of the rat following methylazoxymethanol (MAM) acetate administration by using immunohistochemistry, Western blotting and Northern blotting. Bcl-2 expression in the developing cerebellum is observed in proliferating and differentiating cells, whereas Bax expression is higher in differentiating cells than in proliferating cells during development. Administration of MAM (0.05 microliter/g, i.p.) at postnatal day 3 produces apoptotic cell death, as detected by the characteristic morphology and positivity with the method of in situ end-labeling of nuclear DNA fragmentation of dying cells, in the external granule cell layer of the cerebellum. Dying cells are not stained with Bcl-2 and Bax antibodies. Furthermore, no modification in the intensity of Bcl-2 and Bax protein bands and in the intensity of Bcl-2 and bax mRNA bands on Western and Northern blots, respectively, were observed between control and treated rats. These data indicate that MAM-induced apoptosis is not associated with modifications in the expression of Bcl-2 and Bax. 相似文献
344.
Yoshitaka Takezawa Shin-Ichi Akasaka Tohru Koyama Hisaichi Miya Makoto Shimodera 《Polymer Engineering and Science》1996,36(4):586-591
A novel nondestructive diagnosis using optical reflective analysis is proposed to evaluate thermally aged opaque insulating resins. Values of reflective absorbance (AR) in the visible to near infrared (IR) range were measured under a variety of aging conditions using the bisphenol-A type epoxy resin tapes containing iron oxide pigment. The AR values increased markedly over 180°C before and after heating. This increase was due to the electronic transition absorption caused by thermal oxidation of the resin. By rescaling the aging time as a reduced time, a master curve to evaluate thermal aging of the resin was obtained. Furthermore, a similar curve was obtained using the difference (ΔAR) of the AR values between two wavelengths in the near IR range. This indicated that the surface reflectivity dependence on raggedness and dust and stain could be reduced. Consequently, when the thermal stress was the main cause of aging, the aging and residual life of the resin could be evaluated using this method. 相似文献
345.
Miya S Kimura B Sato M Takahashi H Ishikawa T Suda T Takakura C Fujii T Wiedmann M 《International journal of food microbiology》2008,124(3):239-249
Listeria monocytogenes serotype 4b strains have been identified as the causative agent in many human listeriosis epidemics as well as in a considerable number of sporadic cases. Due to the genetic homogeneity of serotype 4b isolates, development of rapid subtyping methods with high discriminatory power for serotype 4b isolates is required to allow for improved outbreak detection and source tracking. In this study, multilocus variable-number tandem repeat analysis (MLVA) was developed and used to characterize 60 serotype 4b isolates from various sources. All isolates were also characterized by automated EcoRI ribotyping, single enzyme pulsed-field gel electrophoresis (PFGE) with ApaI, and a multilocus sequence typing (MLST) scheme targeting six virulence and virulence-associated genes. Discriminatory power of MLVA (as determined by Simpson Index of Discrimination) was higher than the discriminatory power of any of the other three methods. MLVA markers targeted were found to be stable and did not change when three isolates were passaged daily for 70 days. Cluster analyses of MLVA, PFGE and MLST consistently grouped the same isolates into three major clusters, each of which includes one of the three major L. monocytogenes epidemic clones (i.e., ECI, ECIa and ECII). We conclude that the MLVA method described here (i) provides for more discriminatory subtyping of L. monocytogenes serotype 4b strains than the other three methods, (ii) identifies three major groups within the serotype 4b, which are consistent with the groups identified by other subtyping methods, and (iii) is easy to interpret. Use of MLVA may thus be recommended for subtyping of serotype 4b isolates, including as a secondary more discriminatory subtyping method that could be used after initial isolate characterization by PFGE or ribotyping. 相似文献
346.
Fuminori Arai Hiroki Takeshita Masako Dobashi Katsuhiko Takenaka Masamitsu Miya Tomoo Shiomi 《Polymer》2012,53(3):851-856
To analyze the interplay between crystallization and liquid–liquid phase separation (LLPS), isothermal crystallization behavior of poly(ethylene glycol) (PEG) in blends with isotactic poly(methyl methacrylate) (i-PMMA) was investigated by differential scanning calorimetry (DSC). The blend system had an upper critical solution temperature (UCST) type phase diagram. When the crystallization occurred simultaneously with LLPS, the overall crystallization rate was enhanced at high crystallization temperatures Tc, relatively compared with that of neat PEG. This behavior was interpreted by the combination of the effects of spinodal quench depth ?Ts and usual supercooling degree ?Tc, according to the theory of Mitra and Muthukumar, namely, the crystallization rate is enhanced by the concentration fluctuation-assisted nucleation at high Tc. In the crystallization after LLPS proceeded, on the other hand, the overall crystallization rate was slow and less dependent on the blend composition. In addition, it was revealed by small-angle X-ray scattering measurements that amorphous i-PMMA was excluded from the interlamellar region of PEG crystals in SQ as well as WQ. 相似文献
347.
This study discusses numerical modeling of fatigue and stress corrosion cracking in eddy current simulations. Ten fatigue crack specimens and another 10 stress corrosion crack specimens are prepared for this purpose. The specimens are made of type 316 stainless steel and measure 10 mm in thickness for a general evaluation of the model. Eddy current inspections of the specimens are performed using a differential type plus point probe; the specimens then undergo destructive tests to confirm the true profiles of the cracks. Subsequent numerical simulations are conducted to evaluate the equivalent conductivity and width of the cracks. The simulations demonstrate that a fatigue crack can be modeled as a non-conductive region, and it is not necessary to know exactly how wide the opening of a fatigue crack is. They also revealed, in contrast, that stress corrosion cracking needs to be modeled as a conductive region with a certain width. 相似文献
348.
DD Bannerman MJ Fitzpatrick DY Anderson AK Bhattacharjee TJ Novitsky JD Hasday AS Cross SE Goldblum 《Canadian Metallurgical Quarterly》1998,66(4):1400-1407
Bacterial lipopolysaccharide induces tyrosine phosphorylation of paxillin, actin reorganization, and opening of the transendothelial paracellular pathway through which macromoles flux. In this study, lipid A was shown to be the bioactive portion of the lipopolysaccharide molecule responsible for changes in endothelial barrier function. We then studied whether endotoxin-neutralizing protein, a recombinant peptide that is derived from Limulus antilipopolysaccharide factor and targets lipid A, could block the effects of lipopolysaccharide on protein tyrosine phosphorylation, actin organization, and movement of 14C-bovine serum albumin across bovine pulmonary artery endothelial cell monolayers. In the presence of serum, a 6-h exposure to lipopolysaccharide (10 ng/ml) increased transendothelial 14C-albumin flux compared to the simultaneous media control. Coadministration of endotoxin-neutralizing protein (> or =10 ng/ml) with lipopolysaccharide (10 ng/ml) protected against lipopolysaccharide-induced barrier dysfunction. This protection was dose dependent, conferring total protection at endotoxin-neutralizing protein/lipopolysaccharide ratios of > or =10:1. Similarly, endotoxin-neutralizing protein was capable of blocking the lipopolysaccharide-induced endothelial cell responses that are prerequisite to barrier dysfunction, including tyrosine phosphorylation of paxillin and actin depolymerization. Finally, endotoxin-neutralizing protein cross-protected against lipopolysaccharide derived from diverse gram-negative bacteria. Thus, endotoxin-neutralizing protein offers a novel therapeutic intervention for the vascular endothelial dysfunction of gram-negative sepsis and its attendant endotoxemia. 相似文献
349.
KJ Han H Park SM Yoo SH Baek DY Uhm HS Lee HY Yun NS Kwon KJ Baek 《Canadian Metallurgical Quarterly》1998,62(19):1809-1816
Our previous studies on alpha1-adrenoceptor signaling suggested that G alpha(h) family is a signal mediator in different species. To elucidate the species-specificity of G alpha(h) family in molecular mass, we used the solubilized membranes from mouse heart and the ternary complex preparations containing alpha1-agonist/receptor/G-protein. Binding of [35S]GTPgammaS and the intensity of the [alpha-32P]GTP photoaffinity labeled protein resulting from activation of the alpha1-adrenoceptor were significantly attenuated by the antagonist, phentolamine. The molecular mass of the specific GTP-binding protein was approximately 72-kDa; homologous with G alpha(h) (transglutaminase II) family. Furthermore, immunological cross-reactivity of ternary complex from mouse heart and purified G alpha(h) from rat, guinea pig, and bovine using anti-G alpha(h7) antibody showed that their molecular masses were distinctly different and approximately 72-kDa G alpha(h) from mouse heart was the lowest molecular mass. Consistent with these observations, in co-immunoprecipitation and co-immunoadsorption of the alpha1-adrenoceptor in the ternary complex preparation by anti-G alpha(h7) antibody, the G alpha(h) family protein tightly coupled to alpha1-adrenoceptor. These results demonstrate the species-specificity of G alpha(h) family in molecular mass, especially the lowest molecular mass in mouse. 相似文献
350.