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61.
Kageyama T. Miyamoto T. Makino S. Ikenaga Y. Nishiyama N. Matsutani A. Koyama F. Iga K. 《Electronics letters》2001,37(4):225-226
The authors present a near 1200 nm wavelength vertical-cavity surface-emitting laser (VCSEL) the active region of which is formed by GaInNAs/GaAs quantum wells grown by chemical beam epitaxy. Room temperature continuous-wave operation has been demonstrated with a high slope efficiency of 0.23 W/A, a high output power of over 1.0 mW, and a singlemode output power of 0.34 mW. The fabricated devices with different aperture sizes show low threshold currents of 1.2-2.1 mA and a record low threshold current density of 2.6 kA/cm2 in GaInNAs VCSELs 相似文献
62.
Metabolic diseases have got global health issues. Physical exercise as well as diet therapy is a potent strategy for fighting against the diseases. However, it is often difficult to continue to keep exercise regularly enough to take sufficient effect. Thus, good substitutes for the therapeutic exercise would be greatly beneficial. Recent studies have suggested that 5′AMP-activated protein kinase (AMPK) play important roles in the metabolic alterations by muscle contraction. The notion that AMPK mediates broad effects of physical exercise has been widely accepted, though it has been challenged by observations in some genetically AMPK-disrupted animals. We have demonstrated metabolome-wide significance of AMPK activation in contracting muscles. Thus, pharmacological activation of AMPK can be a promising way to obtain similar effects of the exercise. The relevance of AMPK will be introduced, and possible strategies for obtaining similar effects to the exercise from food factors will be discussed in the current review. 相似文献
63.
A chemo-thermo-mechanically coupled analysis of ground deformation induced by gas hydrate dissociation 总被引:1,自引:0,他引:1
Sayuri Kimoto Fusao Oka Tomohiko Fushita 《International Journal of Mechanical Sciences》2010,52(2):365-3536
We present a numerical analysis of gas hydrate dissociation in hydrate-bearing sediments in the seabed ground. Behavior of multiphase materials has been described within the framework of a macroscopic continuum approach through the use of the theory of porous media. The proposed simulation method has been developed based on chemo-thermo-mechanically coupled analysis, taking into account phase changes from solids to fluids, that is, water and gas, flow of water and gas, heat transfer, and ground deformation. From the numerical results, it has been found that ground deformation is induced by generation and dissipation of water and gas, and by reduction of soil strength due to the loss of hydrates. 相似文献
64.
Keiichi Miyamoto Ayaka Kawasaki Yuko Nagata Masanori Uraya Hisayoshi Kojima Takanori Ito Takashi Horiuchi Nagisa Asakawa Shinsuke Nomura 《Materials science & engineering. C, Materials for biological applications》2011,31(2):158-165
Immunoglobulin A1 (IgA1) concentration in the plasma of patients with IgA nephropathy (IgAN) as the cause of renal failure is higher than that in the plasma of normal controls. IgA1 with abnormal sugars is considered to deposit in the glomerular mesangium, aggravating nephritis in IgAN. Jacalin is a lectin that recognizes sugars on IgA1. However, its selective-recognition for normal-type (ST type, NeuAc-α(2,3)-Gal-β(1,3)-GalNAc) and abnormal-type (T type, Gal-β(1,3)-GalNAc; Tn type, GalNAc; STn type, NeuAc-α(2,6)-GalNAc) sugars α-O-linked to serine/threonine in IgA1 is weak. Therefore, jacalin cannot be used for recognizing specific sugar types on IgA1. We attempted to develop a new recognition method for specific sugar types on IgA1 by utilizing the multirecognition capability of jacalin. Its binding abilities were regulated by heat denaturation with suitable template sugar (galactose or N-acetylgalactosamine). Further, we successfully prepared denatured-jacalin derivatives, which recognized ST-/T-type sugars on IgA1, by sugar-immobilized affinity chromatography. Enzyme-linked immunosorbent assay of denatured-jacalin derivatives, showed the ratios of abnormal sugars on IgA1 in the plasma of IgAN patients and normal controls to be approximately 60% and 20%, respectively. The results proved that profiling of sugar types in IgAN can successfully be performed by solely using jacalin derivatives. 相似文献
65.
The aroma characteristics and volatile profiles of 14 carrot varieties were investigated by sensory evaluations and gas chromatography–mass spectrometry volatile analyses. The sensory map obtained by principal components analysis showed that the sensory attributes comprised 3 categories: sour/green, overall carrot/harsh/ink‐like, and fruity/fresh/sweet. The Kuroda type is characterized by lower intensities of overall carrot/harsh/ink‐like and fruity/fresh/sweet notes. Furthermore, volatile profiling indicated that this type did not have significantly higher amounts of volatiles. Partial least squares regression analysis determined the quantitative contributions to ink‐like, harsh, and fruity carrot aromas; monoterpenes had significant positive correlations with these attributes, while bisabolene isomers had negative correlations. The aroma attribute intensity and contents of volatiles and nutritional compounds are relatively low in the Kuroda type than in other carrot types. This type may be useful for reducing carrot harshness during the development of new carrots with good eating qualities. 相似文献
66.
Sone T Nagamori E Ikeuchi T Mizukami A Takakura Y Kajiyama S Fukusaki E Harashima S Kobayashi A Fukui K 《Journal of Bioscience and Bioengineering》2002,94(1):87-91
We have produced micrometer-sized calcium alginate beads referred to as "bio-beads" that encapsulate plasmid DNA molecules carrying a reporter gene. In order to evaluate the efficiency of the bio-beads in mediating genetic transfection, protoplasts isolated from cultured tobacco cells (BY-2) were transfected with bio-beads containing a plasmid that carries the modified green fluorescent protein gene CaMV35S-sGFP. With the bio-beads treatment, approximately ten-fold higher GFP expression was observed after 24 h incubation compared to that with the conventional method using a naked plasmid solution. Transfection was up to 0.22% efficient. These results indicate that bio-beads have a possibility for efficient transformation in plants. 相似文献
67.
Hiroshi Kageyama Mitsuhide Miyamoto Hajime Akimoto Shigeyuki Nishitani Toshihiro Sato Toshio Miyazawa 《Journal of the Society for Information Display》2006,14(4):345-351
Abstract— A common‐decoder architecture for a data‐driver circuit fabricated by using a polysilicon process has been developed. The architecture achieves a compact circuit and low‐power consumption. In application to an integrated polysilicon data driver for small‐sized displays, this architecture reduces the area of the data driver by removing the vertical bus lines that occupy a large area. It also suppresses the power consumption of the data bus by reducing the number of driven lines in the data bus during word‐to‐word transitions from six to two. By using a conventional 4‐μm design rule, we fabricated an active‐matrix OLED (AMOLED) panel with an integrated six‐bit data‐driver circuit with 384 outputs. The driver circuit had a height of 2.6 mm and a pitch between output lines of 84 μm. The maximum power consumption of the driver was only 5 mW, i.e., 3.8 mW for logic‐data transfer and 1.2 mW for reference‐voltage source. Furthermore, we also fabricated an active‐matrix LCD (AMLCD) panel including driver circuits of the same type as the integrated elements. Six‐bit full‐color images were successfully displayed on both panels. 相似文献
68.
Arai M. Kondo T. Matsutani A. Miyamoto T. Koyama F. 《IEEE journal of selected topics in quantum electronics》2002,8(4):811-816
We carried out the growth of highly strained GaInAs-GaAs quantum wells (QWs) on a patterned substrate for extending emission wavelength on a GaAs substrate. We examined the shift of photoluminescence wavelength of the QWs and showed a large wavelength shift due to the spatial modulation in well thickness and indium composition. We demonstrated a single-mode multiple-wavelength vertical-cavity surface-emitting laser (VCSEL) array on a patterned GaAs substrate covering a new wavelength window of 1.1-1.2 /spl mu/m. By optimizing pattern shape, we achieved multiple-wavelength operation with widely and precisely controlled lasing wavelengths. The maximum lasing span is as large as 77 nm. We carried out a data transmission experiment through 5-km of single-mode fiber with a 2.5 Gb/s/channel. The total throughput reaches 10 Gb/s. The VCSEL-based wavelength-division-multiplexing (WDM) source would be a good candidate for WDM-LAN beyond 10 Gb/s. 相似文献
69.
Matsutomo S. Miyamoto T. Kaneda K. Noguchi S. Yamashita H. 《IEEE transactions on magnetics》2006,42(4):567-570
The finite-element analysis is widely used in design stage of electromagnetic apparatuses. The analysis accuracy depends on the characteristics of the finite-element mesh, e.g., number of nodes, number of elements and shape of elements. Recently, the adaptive finite-element analysis is one of the most promising numerical analysis techniques. In process of the adaptive finite-element method, the error evaluation is one of the important schemes. In this paper, a new error evaluation scheme, which is suitable for electromagnetic problems, is proposed. The proposed error evaluation method is then applied to two-dimensional and three-dimensional magnetostatic field problems for its verification. 相似文献
70.
Noriaki Kurita Norihiko Fukatsu Teruo Ohashi Satoshi Miyamoto Fumiaki Sato Hiroyuki Nakai Kazuhiko Irie 《Metallurgical and Materials Transactions B》1996,27(6):929-935
We have developed a hydrogen sensor for in situ measurements of hydrogen activities in molten copper. The sensor consists of a concentration cell utilizing a proton conductor,
CaZr0.9In0.1O3-δ, as the solid electrolyte. The electromotive force (emf) of the cell was generated by both hydrogen and oxygen activity gradients
across the cell in a high-temperature region simulating the fire refining processes of copper. However, accurate hydrogen
activity in molten copper could be evaluated from the emf if oxygen activity in molten copper was determined simultaneously
by another concentration cell and if the hydrogen and the oxygen activities at the reference electrode were known. The performance
of the sensor was studied under various conditions. The observed good response and reliability of the sensor show that it
should be a powerful tool for improvement of the fire refining process of the molten copper. Theoretical treatment of the
calculation of the emf of the concentration cells using a mixed ionic conductor, i.e., protonic and oxide ionic conductor, as solid electrolytes is also discussed briefly. 相似文献