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1.
To enhance chemical stability and suppress of aggregation of magnetite nanoparticles (MNPs), which are used as a support for thermoresponsive copolymer immobilization, silica coating of the MNPs is applied via the electrooxidation method. Although the resulting silica coated-MNPs also formed aggregates, the size distribution of the aggregate shifted to smaller size range. Because of that, the surface area available for copolymer immobilization increased approximately 6.7 times at maximum as compared with that of the uncoated MNPs. It contributed to the increase of the amount of the immobilized copolymer on the silica-coated MNPs, which is approximately four times larger than that on the uncoated MNPs. Fe3O4 dissolution test confirmed enhancement of chemical stability of MNPs. The thermoresponsive copolymer immobilized on the silica-coated MNPs shows the ability to recycle Cu(II) ion from Cu(II) containing solution by changing temperature with significantly shorter time than those in other thermoresponsive adsorbents in gel form. 相似文献
2.
Akiko Suzuki Mina Minamide Chihiro Iwaya Kenichi Ogata Junichi Iwata 《International journal of molecular sciences》2020,21(23)
Carbohydrates, fats, and proteins are the underlying energy sources for animals and are catabolized through specific biochemical cascades involving numerous enzymes. The catabolites and metabolites in these metabolic pathways are crucial for many cellular functions; therefore, an imbalance and/or dysregulation of these pathways causes cellular dysfunction, resulting in various metabolic diseases. Bone, a highly mineralized organ that serves as a skeleton of the body, undergoes continuous active turnover, which is required for the maintenance of healthy bony components through the deposition and resorption of bone matrix and minerals. This highly coordinated event is regulated throughout life by bone cells such as osteoblasts, osteoclasts, and osteocytes, and requires synchronized activities from different metabolic pathways. Here, we aim to provide a comprehensive review of the cellular metabolism involved in bone development and homeostasis, as revealed by mouse genetic studies. 相似文献
3.
Hideo Yamauchi Junichi Ikejiri Fumio Sato Hiroyuki Oshita Tsuyoshi Honma Takayuki Komatsu 《Journal of the American Ceramic Society》2019,102(11):6658-6667
In recent years, the expansion of demand for lithium ion batteries has resulted in soaring prices of the constituent resources. From the viewpoint of safety, studies on all-solid-state batteries are actively being carried out. In this study, we succeeded in driving all-solid-state batteries derived from nontoxic oxide glasses at room temperature without requiring scarce resources such as lithium and cobalt. The main structure of the ceramic batteries with a simple structure in which Na2FeP2O7 crystallized glass and β″-alumina solid solution are joined by pressureless cofiring at 550°C. During the crystallization of Na2O-Fe2O3-P2O5 glass, fusion with the β″-alumina solid solution is achieved. Reversible charge and discharge of 80 mAh/g were achieved at room temperature. It is not necessary to apply pressure during cell preparation or the use of the batteries. Furthermore, the strong junction at the cathode and electrolyte interface does not peel off during charge and discharge over a long period of 623 cycles. Ex situ X-ray photoelectron spectroscopy revealed partial Fe4+ induction and a reversible charge and discharge reaction even after overcharging to 9 V. It was demonstrated that Na2FeP2O7 is very stable against overcharging to 9 V. 相似文献
4.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts 下载免费PDF全文
5.
Shoko Kasuga Ryota Mori Shunichi Kasahara Junichi Rekimoto 《International journal of human-computer interaction》2019,35(15):1345-1351
Growing evidence suggests that the gradual transformation of visuomotor association drives a distinct learning process from abrupt transformation in humans. In the current study, we developed a novel omnidirectional visuomotor transformation paradigm to study details of such difference in more realistic environment than conventional experimental systems. Participants were asked to perform a repetitive three-dimensional (3D) arm-reaching task to a target on a front touch panel, wearing a video see-through head-mounted device that displayed a rotating view of surrounding images. In the abrupt condition, the images were rotated by 20°; in the gradual condition, the rotation was increased in a stepwise-manner from 0° to 20°. In both conditions, pointing errors were decreased after adaptation. Further, although the aftereffect of adaptation was not different between conditions, the speed of decay of the aftereffect, which was quantified by an exponential fit, was slower in the gradual condition, suggesting longer-lasting aftereffects for the gradual shift. 相似文献
6.
Nosal Briana M. Sakaki Junichi R. Kim Dae-Ok Chun Ock K. 《Food science and biotechnology》2022,31(8):1081-1088
Food Science and Biotechnology - Although coffee has been reported as a major contributor to antioxidants in the diet, there are limited studies assessing how brewing methods and types of coffee... 相似文献
7.
Tsukaho Yahagi Daisuke Kawai Takuma Takahashi Motoyuki Iijima Junichi Tatami 《Journal of the American Ceramic Society》2022,105(3):2046-2057
Si3N4 ceramics with excellent mechanical properties are used for heat dissipation substrates and so on. In order to improve their reliability and expand their application fields, it is desirable to understand and control the electrical properties of Si3N4 ceramics. In this study, the electrical resistivity of Si3N4 ceramics with Yb2O3 additive was investigated by applying various voltages at temperatures ranging from 25°C to 300°C. When Yb2O3 was added as a sintering aid to Si3N4 ceramics, a crystalline J-phase (Yb4Si2O7N2) was formed and their electrical resistivity was significantly lower than that of Y2O3 additive. The electrical resistivity of the Yb2O3-added ceramics decreased with an increase in temperature and applied voltage. Yb existed in multiple valence states, Yb2+ and Yb3+, in the Si3N4 ceramics and the decrease in the electrical resistivity can be attributed hopping conduction through the J-phase. The J-phase in the Si3N4 ceramics was observed to be continuous, and percolation analysis suggested that the J-phase formed an infinite cluster. Therefore, the decrease in the electrical resistivity of the Yb2O3-added Si3N4 ceramics was found mainly to result from the formation of an infinite cluster of J-phase, which exhibits hopping conduction. 相似文献
8.
Sarah Katharina Gaßmeyer Hiroyuki Yoshikawa Junichi Enoki Nadine Hülsemann Prof. Raphael Stoll Prof. Dr. Kenji Miyamoto Prof. Dr. Robert Kourist 《Chembiochem : a European journal of chemical biology》2015,16(13):1943-1949
Structure‐guided protein engineering achieved a variant of the unique racemase AMDase G74C, with 40‐fold increased activity in the racemisation of several arylaliphatic carboxylic acids. Substrate binding during catalysis was investigated by saturation‐transfer‐difference NMR (STD‐NMR) spectroscopy. All atoms of the substrate showed interactions with the enzyme. STD‐NMR measurements revealed distinct nuclear Overhauser effects in experiments with and without molecular conversion. The spectroscopic analysis led to the identification of several amino acid residues whose substitutions increased the activity of G74C. Single amino acid exchanges increased the activity moderately; structure‐guided saturation mutagenesis yielded a quadruple mutant with a 40 times higher reaction rate. This study presents STD‐NMR as versatile tool for the analysis of enzyme–substrate interactions in catalytically competent systems and for the guidance of protein engineering. 相似文献
9.
Jianliang Deng Xiangxia Zhang Shuilong Shen Junichi Koseki 《Bulletin of Engineering Geology and the Environment》2018,77(3):931-939
To reproduce a subaqueous debris flow with a friction coefficient of approximately tan1° in field, material with a huge volume may be involved. In this research, a steady subaqueous debris flow with a friction coefficient of approximately tan1° was produced by using the rotating flume experiment apparatus (Debris Flow Maker, DFM) with only 40 g of silicon powder. Subsequently, the mechanism of the low friction coefficient was interpreted with the hypothesis of dense agglomeration hitting (DAH). DAH means hitting of the dense agglomeration of dense flow on the flume's bottom plane. The following issues on DAH are considered: (I) the high velocity of the flume's bottom plane induces a strong hitting of particles; (II) the hitting elevates the liquid pressure near the boundary between the agglomeration and the flume's bottom plane; (III) the energy loss due to collision inside the particle agglomeration is limited. The experimental results provide an alternative method of producing subaqueous debris flow and an alternative measurement method of its friction coefficient; the hypothesis provides an alternative interpretation on the mechanism of low friction coefficient of subaqueous debris flow. 相似文献