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1.
Monitoring the temperature in liquid hydrogen (LH2) storage tanks on ships is important for the safety of maritime navigation. In addition, accurate temperature measurement is also required for commercial transactions. Temperature and pressure define the density of liquid hydrogen, which is directly linked to trading interests. In this study, we developed and tested a liquid hydrogen temperature monitoring system that uses platinum resistance sensors with a nominal electrical resistance of approximately 1000 Ω at room temperature, PT-1000, for marine applications. The temperature measurements were carried out using a newly developed temperature monitoring system under different pressure conditions. The measured values are compared with a calibrated reference PT-1000 resistance thermometer. We confirm a measurement accuracy of ±50 mK in a pressure range of 0.1 MPa–0.5 MPa.  相似文献   
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In the Li2O–M2O5–TiO2 (M = Nb or Ta) system, Li1+x-yM1-x-3yTix+4yO3 (LMT) forms with a superstructure known as the M-phase, in which the periodical intergrowth layers are inserted in a matrix having a trigonal structure of LiMO3. We have been investigating this unique material focusing on its crystal structure, photoluminescence, and electrical properties.First, the formation area of the superstructure was compared between Nb- and Ta- systems and the difference was accurately analyzed.Second, to apply this unique material as a host material of phosphor, we synthesized new phosphors with various emission colors. Red phosphor, having a high PL intensity with an internal quantum efficiency of 98%, was successfully synthesized and used as a host material of the solid solution for the Ta system. Its high value was the result of the large centroid-to-cation distance of the Eu3+ position in the [(Li, Eu)O12] polyhedral.Further still, toward application of the unique qualities of an electro-ceramic, we successfully fabricated oriented balk ceramics for the Nb system by slip casting in a strong magnetic field of 12 T. As a result, anisotropic electric properties were found along the c-axis, which were caused by the superstructure. We first clarified the mechanism showing that the anisotropic Qf value was due to anisotropic electron conductivity and anisotropic bonding strength within the superstructure.  相似文献   
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There has been an increasing prevalence of neurodegenerative diseases with the rapid increase in aging societies worldwide. Biomarkers that can be used to detect pathological changes before the development of severe neuronal loss and consequently facilitate early intervention with disease-modifying therapeutic modalities are therefore urgently needed. Diffusion magnetic resonance imaging (MRI) is a promising tool that can be used to infer microstructural characteristics of the brain, such as microstructural integrity and complexity, as well as axonal density, order, and myelination, through the utilization of water molecules that are diffused within the tissue, with displacement at the micron scale. Diffusion tensor imaging is the most commonly used diffusion MRI technique to assess the pathophysiology of neurodegenerative diseases. However, diffusion tensor imaging has several limitations, and new technologies, including neurite orientation dispersion and density imaging, diffusion kurtosis imaging, and free-water imaging, have been recently developed as approaches to overcome these constraints. This review provides an overview of these technologies and their potential as biomarkers for the early diagnosis and disease progression of major neurodegenerative diseases.  相似文献   
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Analysis of photoproducts derived from 1‐(methoxynaphthalen‐1‐ylmethyloxy)pyrene initiators and polymer end groups demonstrated that methoxynaphthalen‐1‐ylmethyl carbocation is involved in the initiation steps for both styrene (St) and cyclohexene oxide (CHO) polymerization. Charge transfer from the pyrenyloxy oxygen atom to the methoxynaphthalen‐1‐ylmethyl chromophore in the singlet excited state is assumed to be responsible for the efficient generation of the carbocation species, which also initiates the copolymerization of St and CHO. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40510.  相似文献   
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Reed (Phragmites australis), a commonly used macrophyte in the wetlands constructed for water purification, was investigated as a new biosorbent for the removal of Cu(2+), Cd(2+), Ni(2+), Pb(2+) and Zn(2+) from aqueous solution. The metal adsorption capacity of reed biomass was improved significantly by water-wash, base- and acid-treatment. The maximum sorption of NaOH-pretreated reed biomass was observed near neutral pH for Cu(2+), Cd(2+), Ni(2+) and Zn(2+), while that for Pb(2+) was from an acidic range of pH 4.0 or higher. The maximum metal adsorption capacity on a molar basis assumed by Langmuir model was in the order of Cu(2+)>Ni(2+)>Cd(2+)>Zn(2+)>Pb(2+). Reed biosorbent showed a very high adsorption affinity value, which helps predict its high ability to adsorb heavy metals at low concentration. Desorption of heavy metals and regeneration of the biosorbent was attained simultaneously by acid elution. Even after three cycles of adsorption-elution, the adsorption capacity was regained completely and the desorption efficiency of metal was maintained at around 90%.  相似文献   
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Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors.  相似文献   
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Osteoarthritis of the knee (OAK) is a chronic degenerative disease and progresses with an imbalance of cytokines and macrophages in the joint. Studies regarding the use of platelet-rich plasma (PRP) as a point-of-care treatment for OAK have reported on its effect on tissue repair and suppression of inflammation but few have reported on its effect on macrophages and macrophage polarization. Based on our clinical experience with two types of PRP kits Cellaid Serum Collection Set P type kit (leukocyte-poor-PRP) and an Autologous Protein Solution kit (APS leukocyte-rich-PRP), we investigated the concentrations of humoral factors in PRPs prepared from the two kits and the effect of humoral factors on macrophage phenotypes. We found that the concentrations of cell components and humoral factors differed between PRPs purified using the two kits; APS had a higher concentration of M1 and M2 macrophage related factors. The addition of PRP supernatants to the culture media of monocyte-derived macrophages and M1 polarized macrophages revealed that PRPs suppressed M1 macrophage polarization and promoted M2 macrophage polarization. This research is the first to report the effect of PRPs purified using commercial kits on macrophage polarization.  相似文献   
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