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201.
Thermophilic poly-L-lactide-degrading bacteria were isolated from a garbage fermentor. One of the isolates, strain PL21, was identified as Bacillus smithii based on its physiological properties, sugar assimilation pattern, and partial 16S rDNA sequence. The degradation activity of poly-L-lactide exibited by the culture fluid was parallel to the esterase activity, and the purified enzyme was active against various fatty acid esters and poly-L-lactide, at 60 degrees C and pH 5.  相似文献   
202.
For an ATM switch system, we have developed a 100-Gb/s input/output (I/O) throughput optical I/O interface ATM switch multichip module (MCM) that has 320-ch optical I/O ports. This MCM is fabricated using ceramic (MCM-C) technology and very-small highly-parallel O/E and E/O optical converters. It uses 0.25-μm complementary metal oxide semiconductors (CMOS) ATM switch large scale integrations (LSIs) and has a total I/O throughput of up to 160 Gb/s. A prototype module with total I/O throughput of 100 Gb/s has been partially assembled using eight optical I/O interface blocks, each composed of a 40-ch O/E converter and a 40-ch E/O converter; the data rate per channel is from dc to 700 Mb/s. Using this module we developed an optical I/O interface ATM switch system and confirmed the operation of the optical interface  相似文献   
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Cytomegalovirus (CMV) causes clinical issues primarily in immune-suppressed conditions. CMV-associated anterior uveitis (CMV-AU) is a notable new disease entity manifesting recurrent ocular inflammation in immunocompetent individuals. As patient demographics indicated contributions from genetic background and immunosenescence as possible underlying pathological mechanisms, we analyzed the immunogenetics of the cohort in conjunction with cell phenotypes to identify molecular signatures of CMV-AU. Among the immune cell types, natural killer (NK) cells are main responders against CMV. Therefore, we first characterized variants of polymorphic genes that encode differences in CMV-related human NK cell responses (Killer cell Immunoglobulin-like Receptors (KIR) and HLA class I) in 122 CMV-AU patients. The cases were then stratified according to their genetic features and NK cells were analyzed for human CMV-related markers (CD57, KLRG1, NKG2C) by flow cytometry. KIR3DL1 and HLA class I combinations encoding strong receptor–ligand interactions were present at substantially higher frequencies in CMV-AU. In these cases, NK cell profiling revealed expansion of the subset co-expressing CD57 and KLRG1, and together with KIR3DL1 and the CMV-recognizing NKG2C receptor. The findings imply that a mechanism of CMV-AU pathogenesis likely involves CMV-responding NK cells co-expressing CD57/KLRG1/NKG2C that develop on a genetic background of KIR3DL1/HLA-B allotypes encoding strong receptor–ligand interactions.  相似文献   
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International Journal of Steel Structures - Carbon fiber reinforced plastic, CFRP, plates bonding method is one of the new repair methods for fatigue cracks. In this method, propagation of fatigue...  相似文献   
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Reporter genes such as firefly luciferase are common tools to monitor gene expression in various systems. As reporter gene represents the expression level of the gene of interest with its enzyme activity, firefly luciferase is most frequently used because its luminescent activity is highly sensitive and less time consumable for assay. However, since firefly luciferase is expressed internally in the cell, lysis of the cell is a critical step, and thus it is difficult to monitor the gene expression level continuously. In this report, we utilized secretive Vargula hilgendorfii luciferase modified to cell surface displayed one by fusing with human EGFR transmembrane sequence. This modified Vargula luciferase was expressed on cell surface without losing its bioluminescent activity. Co-transfection with secretive alkaline phosphatase showed that the behaviors of cell surface displayed Vargula luciferase and secretive alkaline phosphatase are comparable to each other. Furthermore, the luminescence of a single cell expressing cell surface displayed Vargula luciferase can be monitored by using photon counting CCD camera, which indicates that this reporter gene can monitor gene expression in a single cell without cell lysis.  相似文献   
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It has been six decades since the concept of phase-plate electron microscopy was first reported by Boersch, but an experimental report on a phase plate with a theoretically rational performance has only recently been released by a group including the present author. Currently, many laboratories around the world are attempting to develop a wide range of phase plates to enhance the capabilities of transmission electron microscopy. They are reporting not only advantages of their own developments but also a fundamental problem inherent to electron beam devices, namely charging, i.e. the accumulation of electrostatic charge. In this report, we review the 60-year history of phase-plate development, with a particular focus on the fundamental issue of phase-plate charging. Next, we review biological applications of qualified phase plates, which have been successful in avoiding charging to some extent. Finally, we compare and discuss electron microscopic images, taken with or without phase plates, of biological targets such as proteins (GroEL and TRPV4), protein complexes (flagellar motor), viruses (T4 phage, ε-15 phage and herpes simplex virus), bacterial (cyanobacteria) and mammalian (PtK2) cells.  相似文献   
210.
A charge–discharge cycling test of a Li/LiCoO2 cell containing ionic liquids based on bis(fluorosulfonyl)imide ([FSI]) as the electrolyte media, revealed significantly better rate properties compared to those of cells using conventional ionic liquids. The use of an 1-ethyl-3-methylimidazolium (EMI+) salt permitted the retention of 70% of the discharge capacity at a 4 C current rate. In contrast, similar performance of cells containing N-methyl-N-propylpyrrolidinium (Py13+) and N-methyl-N-propylpiperidinium (PP13+) salts of [FSI] was limited to operation at 2 and 1 C current rates, respectively. However, the charge/discharge cycling stability of the cell with Py13[FSI] was much better than that of the cell using EMI[FSI].  相似文献   
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