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排序方式: 共有4539条查询结果,搜索用时 15 毫秒
1.
Shunsuke Kato Prof. Akira Onoda Naomasa Taniguchi Prof. Ulrich Schwaneberg Prof. Takashi Hayashi 《Chembiochem : a European journal of chemical biology》2021,22(4):679-685
Directed evolution of Cp*RhIII-linked nitrobindin (NB), a biohybrid catalyst, was performed based on an in vitro screening approach. A key aspect of this effort was the establishment of a high-throughput screening (HTS) platform that involves an affinity purification step employing a starch-agarose resin for a maltose binding protein (MBP) tag. The HTS platform enables efficient preparation of the purified MBP-tagged biohybrid catalysts in a 96-well format and eliminates background influence of the host E. coli cells. Three rounds of directed evolution and screening of more than 4000 clones yielded a Cp*RhIII-linked NB(T98H/L100K/K127E) variant with a 4.9-fold enhanced activity for the cycloaddition of acetophenone oximes with alkynes. It is confirmed that this HTS platform for directed evolution provides an efficient strategy for generating highly active biohybrid catalysts incorporating a synthetic metal cofactor. 相似文献
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Yutaka Sawada Hiroshi Nakazawa W. Andy Take Toshinori Kawabata 《Geotextiles and Geomembranes》2019,47(4):502-513
This paper reports results of full scale testing to further explore potential GCL damage mechanisms in earth dam retrofit applications in seismically active areas; in particular, to a) investigate whether shear displacements could reduce the magnitude of GCL panel overlap during earthquake shaking; b) explore the influence of gravel particles on GCL thickness at localised point of contact; and c) observe the consequences of an accidental exposure of an uncovered GCL to short duration rainfall in terms of moisture content and effects during subsequent compaction. The results of these experiments indicate that even under severe shaking no movements were detected at the GCL panel overlap. Whereas gravel particles were observed to locally reduce the thickness of the GCL to 2.2 mm, no plowing of the particle into the GCL occurred due to a lack of shear displacement at the interface, resulting in no localised internal erosion through the barrier. Furthermore, hydration of GCL panels during construction due to surface wetting was observed to result in a state of hydration less than its post-construction state. These results indicate that although each of the three GCL damage mechanisms cannot be ruled out to ever be relevant in practice, the performance of the GCL retrofitted earth dam tested was satisfactory under even severe Level 2 earthquake shaking, and suggests that the retrofitting of small earth dams with GCLs is a promising strategy to improve their static and seismic resistance. 相似文献
4.
Yoshitake Masuda Kazumi Kato Masahito Kida Jun Otsuka 《International Journal of Applied Ceramic Technology》2019,16(5):1807-1811
SnO2 nanosheets were developed to detect nonanal gas in the order of ppb which was a marker of lung cancer. The nanosheets showed higher resistance change in nonanal gas than that in carbon monoxide (CO), nitrogen dioxide (NO2), acetone (CH3COCH3), hydrogen (H2), ethanol (C2H6O), ammonia (NH3), hydrogen sulfide (H2S), formaldehyde (HCHO), acetaldehyde (CH3CHO), or butanal (C4H8O). Crystal surfaces of the nanosheets would be effective for adsorption of nonanal molecules. Furthermore, it was shown that resistance changed with an increase in carbon number in aldehyde. The nanosheets had molecular selectivity for a series of aldehyde molecules. Molecular recognition of the nanosheets gave us a great advantage to detect nonanal gas which was produced by lung cancer. 相似文献
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Koji Kamagata Christina Andica Ayumi Kato Yuya Saito Wataru Uchida Taku Hatano Matthew Lukies Takashi Ogawa Haruka Takeshige-Amano Toshiaki Akashi Akifumi Hagiwara Shohei Fujita Shigeki Aoki 《International journal of molecular sciences》2021,22(10)
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
6.
Tsuneaki Matsudaira Masashi Wada Naoki Kawashima Miyuki Takeuchi Daisaku Yokoe Takeharu Kato Masasuke Takata Satoshi Kitaoka 《Journal of the European Ceramic Society》2021,41(5):3150-3160
Mass transfer in polycrystalline Yb2SiO5 wafers with precise composition control was evaluated and analyzed by oxygen permeation experiments at high temperatures using an oxygen tracer. Oxygen permeation proceeded due to mutual grain boundary diffusion of oxide ions and Yb ions without synergistic effects such as acceleration or suppression. The oxygen shielding properties of Yb2SiO5 were compared with those of the other line compounds such as Yb2Si2O7 and Al2O3 based on the determined mass transfer parameters. It was found that the more preferentially an oxide ion diffuses in the grain boundary compared to the interior of the grain, the greater the effect of suppressing the movement of the oxide ion by applying an oxygen potential gradient becomes. 相似文献
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This work aims to develop a reliable method to predict mechanical properties of friction-stir-welded 6 xxx-series alloys with experimentally measured welding heat input. A calorimetrical method was utilized to experimentally measure the welding heat input in the friction stir welded of aluminum alloy 6063-T5. Good correlations between the input variables, i.e., welding parameters and physical properties of the materials, and the welding heat inputs obtained with experimental measurements were discovered. The welding heat input can be predicted using the empirical equation derived based on these correlations. Moreover, the results suggested that the thermal conductivities of the welded alloys affected the welding heat input significantly. Mechanical properties, including hardness and tensile properties, of friction-stir-welded aluminum alloy 6063 were in good correlation to the heat input obtained with experimental measurement. These correlations were explained by the evolution of the strengthening precipitates during welding. This work proposed a reliable new route to predict these mechanical responses through the estimation of heat input. 相似文献
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Applicability of vacuum‐microwave drying for tomato fruit based on evaluations of energy cost,color, functional components,and sensory qualities 下载免费PDF全文
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In brain disorders, reactive astrocytes, which are characterized by hypertrophy of the cell body and proliferative properties, are commonly observed. As reactive astrocytes are involved in the pathogenesis of several brain disorders, the control of astrocytic function has been proposed as a therapeutic strategy, and target molecules to effectively control astrocytic functions have been investigated. The production of brain endothelin-1 (ET-1), which increases in brain disorders, is involved in the pathophysiological response of the nervous system. Endothelin B (ETB) receptors are highly expressed in reactive astrocytes and are upregulated by brain injury. Activation of astrocyte ETB receptors promotes the induction of reactive astrocytes. In addition, the production of various astrocyte-derived factors, including neurotrophic factors and vascular permeability regulators, is regulated by ETB receptors. In animal models of Alzheimer’s disease, brain ischemia, neuropathic pain, and traumatic brain injury, ETB-receptor-mediated regulation of astrocytic activation has been reported to improve brain disorders. Therefore, the astrocytic ETB receptor is expected to be a promising drug target to improve several brain disorders. This article reviews the roles of ETB receptors in astrocytic activation and discusses its possible applications in the treatment of brain disorders. 相似文献