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61.
ABSTRACT: Antimicrobial activity of salsa mexicana against Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus , and Saccharomyces cerevisiae was studied. The pressed salsa juice suppressed completely the growth of E. coli, B. subtilis , and S. aureus. K. pneumoniae and B. cereus were suppressed partly but Saccharomyces cerevisiae was not suppressed at all by the juice. Three types of microbicidal or microbiostatic components have been found: (1) H+ , (2) volatile compounds, and (3) non-ionized carboxylic acids or analogous compounds. It is proposed that the supplementation of stink bugs in the salsa seen widely in the south of Mexico is used to intensify the herbal odor of the salsa. 相似文献
62.
Succinate dehydrogenase (SDH) of Saccharomyces cerevisiae consists of four subunits encoded by the SDH1, SDH2, SDH3, and SDH4 genes. We determined the effect of SDH deficiency on the productivity of organic acids in a sake yeast strain Kyokai no. 9. The SDH activity of single disruptants was retained at 30-90% of that of the wild-type strain, but the activity disappeared in double disruptants of the SDH1 and SDH2 or SDH1b (the SDH1 homologue) genes. Two double disruptants showed no growth on a medium containing glycerol as the sole carbon source, while the single disruptants could utilize glycerol. These results indicate that double disruption of the SDH1 and SDH2 or SDH1b genes is required for complete loss of SDH activity and that the SDH1b gene compensates for the function of the SDH1 gene. The sdh1 sdh1b disruptant showed a marked increase in succinate productivity of up to 1.9-fold along with a decrease in malate productivity relative to the wild-type strains under shaking conditions. Under both static and sake brewing conditions, the productivity of these organic acids in the disruptants was virtually unchanged from that in the wild-type strain. Furthermore, SDH activity was undetectable in the wild-type and the disrupted strains under static conditions. These results suggest that SDH activity contributes to succinate production under shaking conditions, but not under static and sake brewing conditions. 相似文献
63.
M Ariyoshi K Nagata K Sato M Kubo K Hiraoka T Hamada G Tadakuma T Abe A Inoue 《Canadian Metallurgical Quarterly》1997,44(2):135-139
The displacement of porcine [125I] insulin bound to rat and lamprey isolated hepatocytes with unlabeled lamprey and porcine insulins was investigated. Binding affinity of lamprey insulin for insulin receptor of rat was similar to that of porcine insulin. In contrast, the binding affinity of lamprey insulin for its own insulin receptor was higher than for a rat receptor. To determine the binding affinity constants of lamprey insulin receptor, the competition binding experiments were carried out on isolated lamprey hepatocytes using lamprey insulin as unlabeled ligand and tracer. The affinity of the same binding sites on lamprey hepatocytes was assessed in similar experiments but employing porcine insulin as unlabeled ligand and tracer. It was found that while Kd of low affinity binding sites on lamprey hepatocytes were similar for lamprey and porcine insulins, the Kd of high affinity binding sites was different: the displacement curve for lamprey insulin being shifted to the left as compared to the curve for porcine insulin. The number of high and low affinity binding sites, calculated independently in Scatchard plots, was equal. We conclude that the high affinity insulin binding sites of lamprey but not of rat hepatocytes reveal some species specificity in ligand-receptor interaction. 相似文献
64.
Tsutomu Tachibana Yuki Nishikawa Nakao Kubo Seiji Takeda 《International journal of molecular sciences》2021,22(1)
Floral organs have evolved from leaves for reproduction, and the morphological analyses help to understand the plant diversity and evolution. Habenaria radiata (syn. Pecteilis radiata) is a terrestrial orchid living in wetlands in Japan, Russia, South Korea, and China. The habitats of this plant in Japan have been reduced because of environmental destruction and overexploitation, and thus it is on the Red List of Japan as a Near Threatened species. One of the three petals of the H. radiata flower is called a lip or labellum, which resembles a flying white bird, egret, or white heron, with its proposed function being to attract pollinators. To understand the diversity of H. radiata plants in different areas, we examined the lip morphology and phylogeny of populations from eight habitats in the Kinki area, Japan. The complex shapes of the lips were quantified and presented as a radar chart, enabling characterization of the morphological difference among populations. Phylogenetic analysis with microsatellite markers that we generated showed the variation of genetic diversity among populations, suggesting the different degrees of inbreeding, outbreeding, and vegetative propagation. Our approach offers a basic method to characterize the morphological and genetic diversity in natural populations. 相似文献
65.
66.
Y. Miyamoto Y. Kubo N. Ono M. Hashimoto T. Takahashi I. Ito F. Arezzo P. Gimondo 《Thin solid films》1995,270(1-2):253-259
A new coil-coating pilot plant, capable of utilizing ion plating, sputtering and plasma-assisted chemical vapor deposition (PACVD) processes, independently or in series, was developed and optimum conditions for TiN, TiC, AlxOy, SiOx and Cr coating were established. This paper is mostly concerned with the results of characterization (conducted in parallel by the authors′ two institutions) of TiN films deposited by ion plating or sputtering onto type-304 stainless steel strips. In particular, the dependence of the basic properties such as chemical composition, structure, adhesion, and color on the coating process are discussed with respect to anti-corrosion, anti-wear, and decorative applications. TiN coatings with a very attractive gold coloration were obtained; they performed well in wear testing, but did not show satisfactory corrosion resistance. However, it was found that the latter can be improved significantly by depositing a SiOx, top layer by PACVD above the TiN coating. Thus the in-line dry coating processes are capable of producing highly functional steel surfaces with decorative color and high corrosion resistance. 相似文献
67.
Shoya Ueno Yuki Nakamura Ken-Ichi Sugioka Masaki Kubo Takao Tsukada Masahito Uchikoshi Hiroyuki Fukuyama 《International Journal of Thermophysics》2017,38(2):16
The normal spectral emissivity of molten Cu–Co alloy with different compositions was measured in the wavelength range of 780 nm to 920 nm and in the temperature range of 1430 K to 1770 K including the undercooled condition by an electromagnetic levitator superimposed with a static magnetic field. The emissivity was determined as the ratio of the radiance from a levitated molten Cu–Co droplet measured by a spectrometer to the radiance from a blackbody calculated by Planck’s law at a given temperature, where a static magnetic field of 2.5 T to 4.5 T was applied to the levitated droplet to suppress the surface oscillation and translational motion of the sample. We found little temperature dependence of the normal spectral emissivity of molten Cu–Co alloy. Concerning the composition dependence, the emissivity decreased markedly above 80 at%Cu and reached that of pure Cu, although its dependence was low between 20 at%Cu and 80 at%Cu. In addition, this composition dependence of the emissivity of molten Cu–Co alloy can be explained well by the Drude free-electron model. 相似文献
68.
Masao Kubo Takashi Matsubara Satoshi Shimizu Hiroshi Sato 《Artificial Life and Robotics》2010,15(2):207-211
In this article, a new localization approach for a team of robots that use the emergent properties of their formation is proposed.
Synchronized behavior sometimes generates spin-off effects that include geometric patterns. The question then arises as to
whether it is possible to use these patterns for something important for robots. In this article, Takayama’s control strategy,
which is a target enclosure formation, is discussed. A simple and useful expansion of Monte Carlo localization by the emergent
pattern is proposed. The proposed algorithms are confirmed through a series of computer simulations. 相似文献
69.
Hideaki Araki Yuki Kubo Aya Mikaduki Kazuo Jimbo Win Shwe Maw Hironori Katagiri Makoto Yamazaki Koichiro Oishi Akiko Takeuchi 《Solar Energy Materials & Solar Cells》2009,93(6-7):996-999
Cu2ZnSnS4 (CZTS) thin films were prepared by sulfurizing precursors deposited by electroplating. The precursors (Cu/Sn/Zn stacked layers) were deposited by electroplating sequentially onto Mo-coated glass substrates. Aqueous solutions containing copper sulfate for Cu plating, tin sulfate for Sn plating and zinc sulfate for Zn plating were used as the electrolytes. The precursors were sulfurized by annealing with sulfur at temperatures of 300, 400, 500 and 600 °C in an N2 gas atmosphere. The X-ray diffraction peaks attributable to CZTS were detected in thin films sulfurized at temperatures above 400 °C. A photovoltaic cell using a CZTS thin film produced by sulfurizing an electroplated Sn-rich precursor at 600 °C exhibited an open-circuit voltage of 262 mV, a short-circuit current of 9.85 mA/cm2 and an efficiency of 0.98%. 相似文献
70.
T Kobayashi S Urakami Y Hirayama T Yamamoto M Nishizawa T Takahara Y Kubo O Hino 《Canadian Metallurgical Quarterly》1997,88(3):254-261
Membrane conductances during hypoosmotic swelling were characterized in rat astrocytes in primary tissue culture. Using whole cell patch clamp techniques, mean +/- SEM cell conductance in isoosmotic phosphate-buffered saline (PBS) was 55.6 +/- 5.8 pS/pF. Cell conductance (mean +/- SEM) increased from this initial value to 187 +/- 46%, 561 +/- 188%, and 1216 +/- 376% within 9 min of exposure to 220 mOsm, 190 mOsm, and 145 mOsm PBS, respectively. With each of these hypoosmotic exposures, no change occurred in membrane capacitance. When CsCl replaced KCl in the microelectrode solution, a similar conductance increase was obtained at each osmolality. However, when gluconate salts were used in place of chloride salts in the electrode solution, no significant conductance increase was observed with 190 mOsm PBS. With a KCl microelectrode solution, all conductance increase which occurred in 190 mOsm PBS was inhibited by 200 microM niflumic acid, but not by 5 mM BaCl(2). Both niflumic acid and BaCl(2) inhibited 60-80% of the conductance increase of cells in 145 mOsm PBS. Using a microelectrode solution containing taurine as the major anion, membrane conductance increased 5-fold when cells were placed in 250 mOsm medium. This conductance increase was completely inhibited by 200 microM niflumic acid. Thus, independent chloride and potassium conductances are activated by hypoosmotic swelling of cultured astrocytes while plasma membrane area is unaltered. The chloride conductance pathway is activated at a significantly lower degree of hypoosmotic exposure than that which activates the potassium pathway and may be permeable to anionic taurine. These conductance pathways may mediate diffusive loss of potassium, chloride, and taurine from these cells during volume regulation following hypoosmotic swelling. 相似文献