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41.
42.
Intervertebral disc (IVD) diseases are common spinal disorders that cause neck or back pain in the presence or absence of an underlying neurological disorder. IVD diseases develop on the basis of degeneration, and there are no established treatments for degeneration. IVD diseases may therefore represent a candidate for the application of regenerative medicine, potentially employing normal human dermal fibroblasts (NHDFs) induced to differentiate into nucleus pulposus (NP) cells. Here, we used a three-dimensional culture system to demonstrate that ectopic expression of MYC, KLF4, NOTO, SOX5, SOX6, and SOX9 in NHDFs generated NP-like cells, detected using Safranin-O staining. Quantitative PCR, microarray analysis, and fluorescence-activated cell sorting revealed that the induced NP cells exhibited a fully differentiated phenotype. These findings may significantly contribute to the development of effective strategies for treating IVD diseases.  相似文献   
43.
To determine the capillary gas chromatographic (GC) elution order of the enantiomers of 4-mercapto-2-alkanones, racemic 4-acetylthio-2-alkanones were synthesized and hydrolyzed by lipases to get enantio-enriched 4-mercapto-2-alkanones that were resolved by capillary gas chromatography using a chiral stationary phase. The obtained enantio-enriched 4-mercapto-2-alkanones were esterified with (S)-2-methoxy-2-(1-naphthyl)propionic acid ((S)-MαNP acid), and the HPLC analysis of MαNP thioesters revealed the same isomeric ratios as the chiral GC analysis of the corresponding thiol enantiomers. The diastereoisomeric thioesters obtained were resolved by HPLC, and the absolute configurations were determined on the basis of 1H NMR anisotropy effects. On the basis of these results, the GC elution order of the enantiomers of 4-mercapto-2-alkanones and of the corresponding 4-acetylthio-2-alkanones could be determined. The combination of enzymatic resolution and MαNP thioesterification proved to be a useful tool to determine the absolute configuration of secondary thiols.  相似文献   
44.
This paper discusses uniaxial ratchetting deformation of lead-free solder alloy Sn–3Ag–0.5Cu and lead-containing solder alloy Sn–37Pb, which were subjected to tension–compression loading with several stress amplitudes and stress ratios, minimum stress over maximum stress. First the uniaxial ratchetting tests were conducted with three maximum stresses and four stress ratios. All tests were conducted using cylindrical bulk specimens of the solder alloys at 313 K. The test results show that there are differences in the ratchetting deformation behavior of the two solder alloys; the larger ratchetting strain occurs in the lead-containing solder alloy than in the lead-free solder alloy. The ratchetting deformation was simulated by the dislocation based constitutive model proposed by Estrin et al. (J Eng Mater Technol 118:441, 1996). The evolution equation of the back stress employed in the constitutive model was modified considering a dynamic recovery term. The effect of the modification of the back stress evolution is discussed by comparing the simulations with the corresponding experimental results. The simulations suggest that the recovery term in the kinematic hardening rule plays an important role in fitting the simulation to the experimental results of the ratchetting deformation of the solder alloys.  相似文献   
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46.
Reactivity of oxide scale on Fe-Cr alloy with Na-containing gases was examined to estimate the stability against sodium (Na): vapors of NaCl and Na2SO4 exposures with air flow at 1073 K. The identified reaction phases were Cr-Mn spinel, Cr2O3, and alloy from the X-ray diffraction of surface with no Na-reaction products. However, the protective oxide scales (Mn-Cr spinel and Cr2O3 layers) on the Fe-Cr alloy were partially decomposed by reacting with Na to form Na-compounds inside the oxide scale/alloy interfaces. In some parts, anomalous oxide scales were found around the oxide scale/Fe-Cr alloy interfaces, with forming Na-rich compounds: the compounds were distributed inner parts of oxide scales around oxide scale/alloy interfaces. The stability of oxide scales and degradation were discussed based on the observed distribution of elements.  相似文献   
47.
48.
The purpose of this paper is to argue that the hybrid formalism fits naturally in the context of David Lewis’s counterfactual logic and that its introduction into this framework is desirable. This hybridization enables us to regard the inference “The pig is Mary; Mary is pregnant; therefore the pig is pregnant” as a process of updating local information (which depends on the given situation) by using global information (independent of the situation). Our hybridization also has the following technical advantages: (i) it preserves the completeness and decidability of Lewis’s logic; (ii) it allows us to characterize the Limit Assumption as a proof-rule with some side-conditions; and (iii) it enables us to establish a general Kripke completeness result by using the proof-rule corresponding to the Limit Assumption.  相似文献   
49.
50.
Avidin-containing polyelectrolyte microcapsules were prepared by a layer-by-layer deposition technique and uptake and release of biotin-labelled fluorescein (b-FITC) was studied. The polyelectrolyte microcapsules were prepared by coating the surface of calcium carbonate (CaCO3) microparticles containing avidin-poly(styrene sulfonate) (PSS) conjugate, followed by dissolution of CaCO3 core in an ethylenediaminetetraacetic acid solution. Release of avidin from the microcapsules was markedly suppressed due to formation of a high molecular weight of avidin-PSS conjugate in the microcapsules. The uptake of b-FITC into the microcapsules was highly enhanced through a strong binding of b-FITC to avidin, as compared to the uptake into avidin-free microcapsules. Release of b-FITC from the microcapsules was accelerated upon addition of biotin, 2-iminobiotin, or lipoic acid in the solution due to the competitive binding of the additives to the binding site of avidin.  相似文献   
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