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排序方式: 共有817条查询结果,搜索用时 15 毫秒
811.
A method to detect production faults in flexible plastic packages with the use of terahertz radiation is presented. Relying on the large difference between the absorption coefficients of plastic and water (for water-filled channel defects) and on the refraction index difference between plastic and air (for air-filled channel defects), our technique consists of focusing and scanning a terahertz beam on the sealed area of the package, followed by detection of the transmitted signal. Compared with previous methods, such as visual and ultrasound inspection, our technique can be applied to optically opaque packages and does not require immersion in a matching liquid. We tested our system on defects that we fabricated as water-filled and air-filled channels imbedded in polyethylene films, with diameters in the range of 10 to 100 microm. The detection limit (the minimum size of a detectable defect) depends on the conveying speed; this relationship was determined and analyzed. The results show that our system has the potential for application in an actual production line for real-time inspection. 相似文献
812.
Kei Murakoshi Ryuichiro Kogure Yuji Wada Shozo Yanagida 《Solar Energy Materials & Solar Cells》1998,55(1-2)
A solid-state solar cell was fabricated by photoelectrochemical polymerization of pyrrole on porous nanocrystalline TiO2 electrode sensitized by the Grätzel dye, cis-di(thiocyanato)-N,N′-bis(2,2′-bipyridyl-4,4′-dicarboxylic acid)-ruthenium (II) dihydrate, [RuL2(NCS)2]), or a newly synthesized cis-Ru(dcb)2(pmp)2 (pmp=3-(pyrrole-1-ylmethyl)-pyridine). Polypyrrole successfully worked as a hole-transport layer with improvement of the cell characteristics when the TiO2 cell with cis-Ru(dcb)2(pmp)2 was compared with the similarly fabricated cells using [RuL2(NCS)2]. The improvement by using Ru(dcb)2(pmp)2 can be explained as due to direct molecular wiring of the polymer-chain to the excited metal center of the complex. 相似文献
813.
Lorenzo Marcucci Hiroki Fukunaga Toshio Yanagida Mitsuhiro Iwaki 《International journal of molecular sciences》2021,22(13)
Muscle energetics reflects the ability of myosin motors to convert chemical energy into mechanical energy. How this process takes place remains one of the most elusive questions in the field. Here, we combined experimental measurements of in vitro sliding velocity based on DNA-origami built filaments carrying myosins with different lever arm length and Monte Carlo simulations based on a model which accounts for three basic components: (i) the geometrical hindrance, (ii) the mechano-sensing mechanism, and (iii) the biased kinetics for stretched or compressed motors. The model simulations showed that the geometrical hindrance due to acto-myosin spatial mismatching and the preferential detachment of compressed motors are synergic in generating the rapid increase in the ATP-ase rate from isometric to moderate velocities of contraction, thus acting as an energy-conservation strategy in muscle contraction. The velocity measurements on a DNA-origami filament that preserves the motors’ distribution showed that geometrical hindrance and biased detachment generate a non-zero sliding velocity even without rotation of the myosin lever-arm, which is widely recognized as the basic event in muscle contraction. Because biased detachment is a mechanism for the rectification of thermal fluctuations, in the Brownian-ratchet framework, we predict that it requires a non-negligible amount of energy to preserve the second law of thermodynamics. Taken together, our theoretical and experimental results elucidate less considered components in the chemo-mechanical energy transduction in muscle. 相似文献
814.
Masayuki Taniguchi Yohei Ishiyama Takeomi Takata Toshihiro Nakanishi Mitsuoki Kaneoke Ken-ichi Watanabe Fujitoshi Yanagida Yi-sheng Chen Tomoaki Kouya Takaaki Tanaka 《Journal of Bioscience and Bioengineering》2010,109(6):570-575
The bacteriocins produced by Lactococcus lactis subsp. lactis C101910 (C101910) and NBRC 12007 (NBRC 12007) were used to prevent the growth of sake spoiling hiochi bacteria (Lactobacillus hilgardii, Lactobacillus fructivorans, and Lactobacillus paracasei) in namazake, which is raw (unpasteurized) sake. The bacteriocin concentrations required for decreasing the viable cell concentrations of L. hilgardii and L. fructivorans below the detection limit (1.0 × 102 cells/ml) in 24 h from the initial concentration of 4.0–9.5 × 105 cells/ml in the namazake at pH 4.5 and at 4°C, were 18–35 U/ml and 5.6 U/ml for the bacteriocin from C101910 and NBRC 12007, respectively. To decrease the viable cell concentration of L. paracasei from the initial concentration of 7.5 × 105 cells/ml to below the detection limit (1.0 × 102 cells/ml) in 24 h, 350 U/ml bacteriocin from C101910 and 140 U/ml bacteriocin from NBRC 12007 were required. In experiments using McIlvaine buffer (pH 4.5) with 15% ethanol instead of namazake as the medium, the viable cell concentrations of L. hilgardii and L. paracasei decreased to less than 1.0 × 102 cells/ml, whereas those of L. fructivorans decreased to less than 1.0 × 103 cells/ml, when bacteriocins were added at the concentrations that had proven effective in namazake. The membrane depolarization assay using a fluorescent probe showed that the presence of ethanol stimulated the collapse of the membrane potential induced by bacteriocins. The ethanol induced collapse of the membrane potential suggests that the application of bacteriocins at the storage stage of namazake is more beneficial than when used in other stages of the sake brewing process. 相似文献
815.
Rubina Rahaman Khadim Raja Kumar Vadivelu Tia Utami Fuad Gandhi Torizal Masaki Nishikawa Yasuyuki Sakai 《International journal of molecular sciences》2022,23(13)
Oxygen, as an external environmental factor, plays a role in the early differentiation of human stem cells, such as induced pluripotent stem cells (hiPSCs). However, the effect of oxygen concentration on the early-stage differentiation of hiPSC is not fully understood, especially in 3D aggregate cultures. In this study, we cultivated the 3D aggregation of hiPSCs on oxygen-permeable microwells under different oxygen concentrations ranging from 2.5 to 20% and found that the aggregates became larger, corresponding to the increase in oxygen level. In a low oxygen environment, the glycolytic pathway was more profound, and the differentiation markers of the three germ layers were upregulated, suggesting that the oxygen concentration can function as a regulator of differentiation during the early stage of development. In conclusion, culturing stem cells on oxygen-permeable microwells may serve as a platform to investigate the effect of oxygen concentration on diverse cell fate decisions during development. 相似文献
816.
Jackin Boaz Jessie Jorissen Lode Oi Ryutaro Wakunami Koki Yamamoto Kenji Ichihashi Yasuyuki Bekaert Philippe Lafruit Gauthier 《Virtual Reality》2023,27(2):761-775
Virtual Reality - Heads-up displays that are ‘see-through’ and ‘curved’ and capable of displaying 3D contents are considered crucial for augmented reality-based navigation... 相似文献
817.
Siqian Wang Wei Hsun Hu Yasuyuki Nakamura Nanami Fujisawa Ane Eline Herlyng Mitsuhiro Ebara Masanobu Naito 《Advanced functional materials》2023,33(36):2215064
Development of tough, reusable adhesives is important, but remains a major challenge, especially in water. A tough reusable adhesive that resets entirely to its virgin condition when needed is reported using caffeic acid. Here, caffeic acid is employed as adhesive moiety to achieve such the functions due to its dual characteristics: an adhesive moiety from mussel-inspired catechol and a photo-reversible crosslink from cinnamic acid. Adhesion involves a two-step process. First, the caffeic acid-functionalized polymer is applied to the adherend, followed by UV irradiation (peak wavelength of light-emitting diode, λP: 365 nm) to form a durable pre-applied adhesive (PAA) layer through crosslinking among the caffeic acid moieties. Second, thermal activation of the PAA layer ensures repeated adhesion to a variety of adherends ( R euse- M any mode). The cyclic dimer of the caffeic acid moiety is de-crosslinked by UV irradiation at λP: 254 nm. This allows the complete removal of the adhesive residues from the adherends when the adhesive is no longer needed ( R eset- O n demand mode). Furthermore, using magnetic nanoparticles, the caffeic acid-functionalized polymer can be activated remotely under water by magnetic induction heating. This study paves the way for the rational design of bio-inspired adhesives that outperform nature using plant-derived raw materials. 相似文献