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31.
We investigated the effects of skimmed milk and its protein fractions (casein, whey, globulin, and albumin) on the injury and inactivation of Escherichia coli K-12 by high hydrostatic pressure (HHP) treatment. The protective effect of skimmed milk on HHP-mediated inactivation and injury of E. coli increased with increases in the skimmed milk concentration. However, protein fractions derived from skimmed milk did not exhibit this protective effect. Microscopy analysis by DAPI/PI staining indicated that some cells were localized in the solid portion of skimmed milk, and some of these cells were alive. The coagulated fraction derived from the autoclaved whey fraction also showed a significant protective effect. We speculate that the solid portion in skimmed milk could provide the protective effect to bacterial cells.  相似文献   
32.
The chiral indan derivative (S)-2 (2-[(8S)-1,6,7,8-tetrahydro-2H-indeno[5,4-b]furan-8-yl]ethyl-amine) was synthesized by enzyme-catalyzed asymmetric hydrolysis of the racemic acetamide 1 (N-[2-(1,6,7,8-tetrahydro-2H-indeno[5,4-b]furan-8-yl)ethyl]acetamide). The reaction was carried out using Bacillus sp. SUI-12 screened for the ability to hydrolyze 1 to give (S)-2 with high enantioselectivity. In a scaled-up experiment, a low reaction rate was observed. However, by changing the culture medium and the reaction conditions, it became possible to run the reaction to 40% conversion on a 10-g or more scale, obtaining (S)-2 at >;99% enantiomeric excess (ee). The (S)-2 obtained was available for the synthesis of the melatonin receptor agonist TAK-375 (N-[2-[(8S)-1,6,7,8-tetrahydro-2H-indeno[5,4-b]furan-8-yl]ethyl]propanamide).  相似文献   
33.
Achieving ultra-high magnetic-recording density in hard disk drives (HDDs) requires clarification of flow-induced vibration issues. In particular, it is necessary to reduce the flow-induced disk vibration called disk flutter. Thus far, however, there has been no experimental research related to disk flutter in actual HDDs. For this study, therefore, the disk-flutter issues have been studied experimentally, using an actual 2.5-in. HDD with one disk and two magnetic heads. The aim was to study the effect of operating magnetic-head mechanisms on flow-induced disk flutter. This study evaluated disk flutter as well as static pressure distribution in the actual HDD, by taking measurements while changing the operating modes of the magnetic-head mechanism as well as the number of operating air-bearing sliders. The study demonstrated that the disk-flutter amplitude increases and its frequency decreases when the magnetic-head mechanisms are operating. It was also found that the amount of decrease in the disk-flutter frequency depends on the number of operating air-bearing sliders whose amplitude increase varies with the specific operating mode of the head mechanisms, such as whether it is in track-following or seek modes. In addition, operation of the magnetic-head mechanisms generated non-uniform static pressure distribution within the HDD. These factors suggest that a decrease in disk-flutter frequency results from the slider-coupled vibration and an increase in disk-flutter amplitude results from the static pressure changes as well as air-following changes, as these vary with the actual operation of the disk head mechanism. From these experimental results, it appears that the disk-flutter issues in actual HDDs should be considered as a system that includes the operation of the magnetic-head mechanisms and disk-coupled vibration.  相似文献   
34.
It has been mandatory to label five allergenic substances (AS; egg, milk, wheat, buckwheat and peanut) in all processed foods, since April 2002 in Japan. Two kinds of ELISA kits have been provided as screening test kits for the Japanese official method. The kits have many advantages but some disadvantages, i.e., the kits are not necessarily suitable for daily monitoring in food manufacturing plants, because they require various analytical equipments and the use of complicated procedures. To overcome these drawbacks, we have developed other diagnostic kits based on immunochromatography that should enable more rapid and simple screening for food allergens. Then we examined the performance of these immunochromatographic test kits (IC kits) in terms of sensitivity, repeatability and cross-reactivity to AS proteins in 11 kinds of food models with various heating conditions and physical properties. We also examined processed food models including AS protein of constant concentration, using the IC kits and ELISA kits, and compared the results. The IC kits detected AS proteins at 5 microg/g in the extracts from processed food models, and provided highly reproducible results. Cross-reactivity among the AS proteins was not observed. The results obtained using the IC kits showed performance equivalent to that of the ELISA kits we examined in unheating processed food models including AS proteins of constant concentration. The IC kits should be more suitable for daily monitoring in food manufacturing plants.  相似文献   
35.
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases.  相似文献   
36.
Hexagonal-structured self-assemblies of nanocrystalline (anatase) titania templated by cetyltrimethylammonium bromide (C(16)H(33)N(CH(3))(3)Br; CTAB) (Hex-ncTiO(2)/CTAB Nanoskeleton) were formed after mixing of aqueous solutions containing CTAB spherical micelles and titanium oxysulfate acid hydrate (TiOSO(4).xH(2)SO(4).xH(2)O) as a titania precursor in the absence of any other additives. Formation mechanism of the Hex-ncTiO(2)/CTAB Nanoskeleton was examined in terms of the reaction temperature, titania precursor/CTAB mixing ratio, surfactant type, electrostatic interaction, micelle formation and molecular component. We found that crystal growth of crystalline (anatase) titania (polymorphic crystallization) was promoted with higher temperature and lower titania precursor content in aqueous solutions. In addition, we revealed that the crystalline (anatase) titania was formed in polycation, poly(allylamine hydrochloride ([CH(2)CH(CH(2)NH(2))HCl](n); PAH), and formamide (HCONH(2)) solutions. On the other hand, no titania formation was observed in anionic systems such as sodium dodecyl sulfate (CH(3)(CH(2))(11)OSO(3)Na; SDS) and poly(sodium 4-styrenesulfonate ([C(8)H(7)SO(3)Na](n); PSSS). This indicates that hydrolysis reaction of the titania precursor is initiated by not only cations but also nitrogen atoms in molecules and polymers. Hexagonally structure was formed in only cationic surfactant micellar solutions but not in polycation solutions and formamide.  相似文献   
37.
An Al-3% Mg solid solution alloy was subjected to intense plastic deformation, using either equal-channel angular (ECA) pressing or torsion straining, to produce grain sizes in the submicrometer range. Static annealing at elevated temperatures led to grain growth and average grain sizes of up to > 100 μm. As-fabricated and statically annealed specimens were used to determine the variation in microhardness with grain size, and results confirm that the Hall-Petch relationship persists down to at least the finest grain size examined experimentally (∼90 nm). The results provide no evidence to support the claims of a negative Hall-Petch slope when the average grain size is very small, but there is evidence of a decrease in the slope of the Hall-Petch plot at the very finest grain sizes (< 150 nm); this is attributed to the increased participation of mobile extrinsic dislocations in the boundary regions when taking the hardness measurements.  相似文献   
38.
This paper presents the design of nonlinear servo systems using the fuzzy method. The idea behind this control method is to divide the operating region of a nonlinear system into a collection of local linear servo control systems and apply the fuzzy method for calculation of the control input. The control input of each local linear servo system is calculated using the Davison–Smith method and the Hikita pole assignment method. We can prove that all states of the fuzzy servo system are bounded and that the output errors converge to zero by the Lyapunov method. Simulations on a nonlinear mass‐spring‐damper system illustrate the effectiveness of the proposed method.  相似文献   
39.
40.
We investigated by numerical analysis the dependence of vaporization behavior of aluminum particles injected into transferred type arc plasma on injection conditions in synthesis of aluminum nitride ultra fine particles. On the basis of calculation results, we chose one proper injection condition where aluminum particles vaporized more. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(2): 46–52, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20852  相似文献   
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