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101.
Sano D  Fukushi K  Yoshida Y  Omura T 《Water research》2003,37(14):3490-3498
Pathogenic enteric viruses can be retained in municipal sewage sludge as has been reported by many researchers. Although the RT-PCR technique has been extensively employed for the virus detection from various environmental samples, the application of RT-PCR to the detection of viruses in sewage sludge has the difficulty because of inhibitory substances to the gene amplification. However, a combination of the enzymatic virus elution (EVE) method with RT-PCR made it possible to effectively detect viruses in sewage sludge. The enzymatic breakdown of sludge flocs in the EVE method enhanced the virus elution from poliovirus 1 (PV1)-inoculated sewage sludge, and the detection of PV1 was performed by RT-PCR without any inhibitions. On the contrary, the application of RT-PCR to the viral assay in the US EPA method using the 10% beef extract solution was not practical because of inhibitions to the viral gene amplification. The combination of the EVE method using lysozyme (polysaccharide-degrading enzyme), papain (protease), and chymotrypsin (protease) with RT-PCR resulted in a virus recovery efficiency of 31%, but a synergistic effect of these enzymes on the virus recovery efficiency was not observed. The EVE method using lysozyme or papain could be a promising procedure for the virus elution from sewage sludge in detecting these viruses with RT-PCR.  相似文献   
102.
In order to promote the production and use of electricity generated from renewable energy sources, support schemes such as the Renewables Portfolio Standard and various green power programs have been implemented. When evaluating the costs and benefits associated with those schemes, people need accurate information about the characteristics of renewable generation. The objective of the present paper is to identify the kind of information to be provided to lay people in Japan in order to enhance their understanding of biomass generation. We used the two-stage “mental model” method to conduct open-ended interviews and a questionnaire survey to reveal people’s beliefs about biomass generation. From the survey results, it was identified that the information to be provided should include the following: (a) definitions of biomass and biomass generation, (b) specific generation technologies, (c) the carbon neutral concept of biomass, (d) non-use of energy food crops in Japan, (e) sustainable availability of resources under certain conditions, and (f) high generation costs with their causes, such as collection costs of resources.  相似文献   
103.
In order to attain high diffraction efficiency in high-energy X-ray region, we have developed multilevel-type (6-step) multilayer FZPs with the diameter of 70 μm, which composed of concentric multilayers of alternating high-Z (Cu), low-Z (Al), and four types of composite materials (Cu, Al) layers. Such a multilevel-type FZP with high diffraction efficiency contributes the reduction of the radiation damage to biological specimens, the simplification of the X-ray optical system. Some FZPs are fabricated and their diffraction efficiencies were evaluated at the beamline of SPring-8. For one FZP, the peak efficiency for the 1st-order diffraction of 51% has been obtained at 70 keV. The efficiencies higher than 40% have been achieved in the wide energy range of 70-90 keV. That for the 2nd-order diffraction of 46% has been obtained at 37.5 keV. For another FZP, the peak efficiency for the 1st-order diffraction of 52% has been obtained at 41.3 keV. The efficiencies higher than 45% have been achieved in the wide energy range of 33-49.5 keV.  相似文献   
104.
Dynamic microfluidic gelation enables the fabrication of bundle-structured multiple parallel microgel filaments from an aqueous two-phase system. The formation mechanism of shear-induced filaments from an alginate (Alg)/polyvinyl alcohol (PVA) blend is studied using red-colored PVA and a titanium alkoxide PVA crosslinker. Bundle-structured Alg microgel filaments are formed through contact with a Ca2+ crosslinker. In this process, the PVA acts as a sacrificial polymer to maintain the Alg gel filaments because approximately 90% of the red-colored PVA is released from the Ca2+-crosslinked Alg gel filaments into the wash water. In addition, the fabrication of PVA gel filaments shows that the sacrificial PVA is also transformed into fibrillar domains under shear. However, the filament structure cannot be formed from a single-phase PVA/Alg solution. These results clearly show that the bundle-structured gel filaments are maintained by preventing the fusion of filaments during gelation based on the tendency of the non-crosslinked filaments to cause splitting of the gelled filaments.  相似文献   
105.
A non-destructive method for monitoring creaming of emulsion-based formulations is in great demand because it allows us to understand fully their instability mechanisms. This study was aimed at demonstrating the usefulness of magnetic resonance (MR) techniques, including MR imaging (MRI) and MR spectroscopy (MRS), for evaluating the physicochemical stability of emulsion-based formulations. Emulsions that are applicable as the base of practical skin creams were used as test samples. Substantial creaming was developed by centrifugation, which was then monitored by MRI. The creaming oil droplet layer and aqueous phase were clearly distinguished by quantitative MRI by measuring T1 and the apparent diffusion coefficient. Components in a selected volume in the emulsions could be analyzed using MRS. Then, model emulsions having different hydrophilic–lipophilic balance (HLB) values were tested, and the optimal HLB value for a stable dispersion was determined. In addition, the MRI examination enables the detection of creaming occurring in a polyethylene tube, which is commonly used for commercial products, without losing any image quality. These findings strongly indicate that MR techniques are powerful tools to evaluate the physicochemical stability of emulsion-based formulations. This study will make a great contribution to the development and quality control of emulsion-based formulations.  相似文献   
106.
Large myelinated club ending and small-vesicle bouton synapses on the distal part of the lateral dendrite of the goldfish Mauthner cell were investigated with thin section, freeze-fracture, and immunocytochemical electron microscopic methods. Large myelinated club endings form mixed synapses, having both gap junctions and chemical synaptic junctions. The correlation of the number of gap junction particles (connexons) and the data from electrophysiological studies of single large myelinated club ending synapses suggest that only a small fraction of gap junction channels are open at any given time during electrical synaptic transmission. The chemical synaptic junctions at the large myelinated club ending synapse have large, round synaptic vesicles, indicating that they are excitatory. This result is in agreement with electrophysiological data demonstrating the excitatory nature of this chemical synapse. Freeze-fracture of these excitatory chemical synaptic junctions reveals the presence of the intramembrane particle aggregates in the postsynaptic E face. Small-vesicle boutons form chemical synaptic junctions with small, flat or oval synaptic vesicles. These structural data, in combination with previous electrophysiological studies, suggest that the small-vesicle bouton synapses are inhibitory. In support of this theory, the cytoplasmic side of the postsynaptic membrane of some of these synapses show positive immunocytochemical reaction to monoclonal antibodies against the rat glycine receptor. Freeze-fracture data reveal intramembrane particle aggregates in the postsynaptic P face of some small-vesicle bouton synapses which could possibly represent glycine receptor aggregates.  相似文献   
107.
The conformational change and the alignment behavior of poly-4BCMU were investigated in compression, de-compression and re-compression process using LB method. In compression process, the conformation of poly-4BCMU changed from random-coil conformation to rigid-rod one. With the increase of surface pressure, poly-4BCMU with rigid-rod conformation gathered into bundles and they aligned perpendicular to the compressing direction. Once stopping the compression and releasing the surface pressure, the bundle textures released packing. In this process (de-compression process), the conformational change never occurred. Discrete slender fibrils gathered again in re-compression process, resulting in the formation of close-packed bundles with high molecular ordering.  相似文献   
108.
Miscibility of binary and ternary polymer blends composed of thermotropic liquid crystalline polycarbonate (LCPC), poly(vinyl alcohol) (PVA), and chitosan was investigated by viscosity method, FTIR spectrum, and scanning electron microscope techniques. Effect of addition of chitosan as a compatibilizer on miscibility and morphology of binary LCPC/chitosan and PVA/chitosan and ternary LCPC/PVA/chitosan polymer blends was discussed. These measurements indicated that addition of chitosan into the blends of LCPC with PVA leads to an increase of miscibility and a formation of clear fibril structures on fractured surfaces, which are due to intermolecular hydrogen‐bonding interaction between LCPC, PVA, and chitosan chains. It was suggested that side‐chain hydroxy group of PVA and amino and hydroxy groups of chitosan play an important role in the formation of miscible phase and improvement of morphology in binary and ternary blends composed of LCPC, PVA, and chitosan. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1616–1622, 2004  相似文献   
109.
As a basis for theories of psychopathology, clinical psychology and related disciplines need sound taxonomies that are generalizable across diverse populations. To test the generalizability of a statistically derived 8-syndrome taxonomic model for youth psychopathology, confirmatory factor analyses (CFAs) were performed on the Youth Self-Report (T. M. Achenbach & L. A. Rescorla, 2001) completed by 30,243 youths 11-18 years old from 23 societies. The 8-syndrome taxonomic model met criteria for good fit to the data from each society. This was consistent with findings for the parent-completed Child Behavior Checklist (Achenbach & Rescorla, 2001) and the teacher-completed Teacher's Report Form (Achenbach & Rescorla, 2001) from many societies. Separate CFAs by gender and age group supported the 8-syndrome model for boys and girls and for younger and older youths within individual societies. The findings provide initial support for the taxonomic generalizability of the 8-syndrome model across very diverse societies, both genders, and 2 age groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Buccal hairy leucoplakia is associated with Epstein-Barr and HIV virus infections. The main symptom is the characteristic hairy lesion on side parts of the tongue without any other clinical sign. Histologically, there are hyperkeratosis, vacuolar degeneration, and presence of Candida, but no inflammatory infiltration. Antiviral drugs led to the regression of lesions, but there is a trend to relapse when treatment is interrupted.  相似文献   
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