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1.
In recent years drastic shifts in the paradigms of politics, economics and technologies have occurred throughout the world. The shifts in these three fields are all related. It is our responsibility to investigate these shifts from the aspects of society and mankind for the prosperity of future generations. For this, societies should share with each other their wisdom and knowledge in an effort to plan for the future.Presented at conference on Ecology of Science and Technology, Japan Science Foundation, Tokyo, 1992.  相似文献   
2.
Persistent acid production by Lactobacillus delbrueckii subsp. bulgaricus during refrigerated storage is a major cause of reduced viability of probiotic strains such as Bifidobacterium breve in yoghurt. It was established that H+ -ATPase-defective mutants of lactic acid bacteria have reduced growth and metabolism in low pH environments. Therefore, the aim of this study was to evaluate inhibition of post-acidification and maintenance of B. breve viability in yoghurt fermented by L. delbrueckii subsp. bulgaricus mutants with reduced membrane-bound H+ -ATPase activity during refrigerated storage. Spontaneous neomycin mutants of L. delbrueckii subsp. bulgaricus that had a significantly (P < or = 0.05) reduced H+ -ATPase activity were successfully isolated. Yoghurt fermented using L. delbrueckii subsp. bulgaricus SBT0164 No. 55-1 (mutant) starter culture had markedly reduced post-acidification and maintained viability (> or = 10(8) CFU/ml) of both Bifidobacteruim breve JCM 1192(T) and Bifidobacteruim breve JCM 7017 during storage at 10 degrees C for 21 days. These results clearly showed that yoghurt fermented by mutants of L. delbrueckii subsp. bulgaricus with reduced membrane-bound H+ -ATPase activity has reduced post-acidification that prolongs viability of B. breve in yoghurt during refrigerated storage.  相似文献   
3.
The effects of difructose anhydride III (di-D-fructofuranose-1,2':2,3'-dianhydride; DFA III) administration (3% DFA III for 4 weeks) on rat intestinal microbiota were examined using denaturing gradient gel electrophoresis (DGGE). According to DGGE profiles, the number of bacteria related to Bacteroides acidofaciens and uncultured bacteria within the Clostridium lituseburense group decreased, while that of bacteria related to Bacteroides vulgatus, Bacteroides uniformis and Ruminococcus productus increased in DFA III-fed rat cecum. In the cecal contents of DFA III-fed rats, a lowering of pH and an increase in short chain fatty acids (SCFAs), especially acetic acid, were observed. The DFA III-assimilating bacterium, Ruminococcus sp. M-1, was isolated from the cecal contents of DFA III-fed rats. The strain had 98% similarity with R. productus ATCC 27340T (L76595), and mainly produced acetic acid. These results confirmed that the bacteria harmful to host health were not increased by DFA III administration. Moreover, DFA III stimulated the growth of Ruminococcus sp. M-1 producing acetic acid, which may alter the intestinal microbiota towards a healthier composition. It is expected that DFA III would be a new candidate as a prebiotic.  相似文献   
4.
5.
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   
6.
A highly potent allelopathic factor, lepidimoide, was initially extracted from mucilage of germinated cress seeds. Polysaccharide extracted from okra (Abelmoschus esculentum Moench) is considered to have a similar structure to lepidimoide as its repeating unit. We therefore initiated the screening of enzymes capable of degrading okra polysaccharide into lepidimoide from endophytes. We discovered an endophytic fungal strain AHU9748 isolated from Coleus galeatus, which produced an oligosaccharide having similar properties to lepidimoide on thin layer chromatography. The physico-chemical data from ESI-MS, NMR spectra and other analyses also showed the purified product to be identical to lepidimoide. The strain AHU9748 was identified as a fungus belonging to the coelomycetes, closely related to the genus Colletotrichum, based on morphological characteristics and sequence analysis of the 18S rDNA and ITS region.  相似文献   
7.
When performing multiresidue analysis of pesticides, the recovery of thiometon was less than 20% from carrots and eggplants, but about 100% from garlic chives and welsh onions. The recovery of thiometon was found to depend on the lot of ethyl acetate. A 2-year-old lot of ethyl acetate caused degradation of thiometon, but a fresh lot of ethyl acetate did not. Analysis showed that ethyl acetate stored for 2 years contained about 5 microL/mL of acetaldehyde. Thiometon was also degraded by acetone or acetonitrile, when acetaldehyde was added to them, in the same manner as by aged ethyl acetate. The fact that the recovery of thiometon from welsh onions was about 100% indicated that some of the mercaptans in allium vegetables may prevent thiometon degradation. Mercaptans such as L-cysteine and 3-mercaptoproionic acid were confirmed to prevent the degradation of thiometon and disulfoton. These findings show that mercaptans may be useful additives for analyzing thiometon and disulfoton.  相似文献   
8.
Optical tweezers are powerful tools for manipulating single DNA molecules using fluorescence microscopy, particularly in nanotechnology‐based DNA analysis. We previously proposed a manipulation technique using microstructures driven by optical tweezers that allows the handling of single giant DNA molecules of millimetre length that cannot be manipulated by conventional techniques. To further develop this technique, the authors characterised the microstructures quantitatively from the view point of fabrication and efficiency of DNA manipulation under a fluorescence microscope. The success rate and precision of the fabrications were evaluated. The results indicate that the microstructures are obtained in an aqueous solution with a precision ∼50 nm at concentrations in the order of 106 particles/ml. The visibility of these microstructures under a fluorescence microscope was also characterised, along with the elucidation of the fabrication parameters needed to fine tune visibility. Manipulating yeast chromosomal DNA molecules with the microstructures illustrated the relationship between the efficiency of manipulation and the geometrical shape of the microstructure. This report provides the guidelines for designing microstructures used in single DNA molecule analysis based on on‐site DNA manipulation, and is expected to broaden the applications of this technique in the future.Inspec keywords: DNA, molecular biophysics, fluorescence, optical microscopy, radiation pressure, biological techniquesOther keywords: optically driven microstructures, single DNA molecule analysis, fluorescence microscopy, optical tweezers, nanotechnology‐based DNA analysis, manipulation technique, aqueous solution, fine tune visibility, yeast chromosomal DNA molecules, geometrical shape, on‐site DNA manipulation  相似文献   
9.
The promotional effects of Co in CoMoAl2O3 hydrodesulfurization (HDS) catalysts were studied by means of X-ray photoelectron spectroscopy. The higher MoO3-content MoAl2O3 catalysts (10 and 20 wt% MoO3) contain mobile Mo, which migrates from the pores to the outermost surface layers of the catalysts and segregates to form less active crystalline MoS2 during the HDS reaction, while in the case of MoAl2O3 (5 wt% MoO3) catalyst: no migration of Mo was observed. It is revealed that the Co in CoMoAl2O3 catalyst inhibits the migration and segregation of Mo and that it keeps Mo effective for the HDS reaction, since no surface enrichment of Mo was observed. It is concluded that stabilization of the Mo monomolecular layer is the main role of Co. The active species of Mo is suggested to have the composition of S/Mo(IV) = 1 on the basis of the sulfur contents of the catalysts under the mild HDS reaction conditions.  相似文献   
10.
In this study, we examined the ability of tumour necrosis factor-alpha (TNF) to stimulate the mitogen-activated protein (MAP) kinase homologues p42/44 MAP kinase, c-Jun NH2-terminal kinase (JNK) and p38 MAP kinase and its effect upon DNA synthesis in primary cultures of bovine aortic endothelial cells (BAECs). TNF strongly stimulated p38 MAP kinase and JNK activity in both a time- and concentration-dependent manner. By contrast, TNF was a very poor activator of p42/44 MAP kinase relative to the known activator of p42/44 MAP kinase in endothelial cells, adenosine triphosphate (ATP). TNF-stimulated activation of p38 MAP kinase, and MAPKAP kinase-2, a known downstream target of p38 MAP kinase, was strongly inhibited by pre-incubation with the p38 MAP kinase inhibitor SB203580, whereas the minor activation of p42/44 MAP kinase was abolished by pre-incubation of the cell with the novel MAP kinase kinase 1 inhibitor PD098059. Addition of TNF resulted in a 50-60% decrease in DNA synthesis in BAECs. Pre-incubation with PD098059 or co-incubation with ATP failed to modify the inhibitory effect of TNF upon DNA synthesis. SB203580 reduced basal DNA synthesis by approximately 50%; however, if failed to modify the inhibition mediated by TNF. These results indicate that TNF strongly activates both p38 MAP kinase, JNK and, to a minor extent, p42/p44 MAP kinase. It is likely that only one of these kinases, JNK, plays a role in the regulation of DNA synthesis in these cells.  相似文献   
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