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排序方式: 共有792条查询结果,搜索用时 15 毫秒
781.
H. Shirai S. Oshita Y. Makino J. Sugiyama M. Yoshimura 《Food and Bioprocess Technology》2014,7(12):3455-3465
To develop a rapid and nondestructive hygiene-monitoring system in meat-processing plants, plate count and ATP content on pork meat surfaces were quantitatively determined with particular attention to NAD(P)H fluorescence produced by microorganisms. An excitation (Ex)–emission (Em) matrix (EEM) was obtained, and the five fluorescence peaks of tryptophan, NAD(P)H, zinc protoporphyrin IX, protoporphyrin IX, and riboflavin were observed. Plate count and ATP content were predicted with good accuracy [r p?=?0.90–0.94 and root mean square error of prediction (RMSEP)?=?log10 (0.68–0.79 CFU cm?2) for plate count and r p?=?0.84–0.89 and RMSEP?=?log10 (0.61–0.71, mol cm?2) for ATP content]. Two-dimensional Savitzky–Golay second-order differentiation was found to be a powerful preprocessing tool of EEMs to improve prediction accuracy. Better prediction accuracy was obtained when the sensitivity of the fluorescence spectrophotometer was set to focus on fluorescence from NAD(P)H than that from both tryptophan and NAD(P)H. However, little linear relationship was observed between plate count and fluorescence intensity from NAD(P)H (R 2?=?0.31). The absolute value of regression coefficient (RC) of partial least-squares regression (PLSR) at the wavelength assigned to NAD(P)H, zinc protoporphyrin IX, protoporphyrin IX, and riboflavin was high. It can be concluded that a good prediction model was developed in which four fluorescence compounds of NAD(P)H, zinc protoporphyrin IX, protoporphyrin IX, and riboflavin contribute to the prediction model, and these compounds are probably produced by microorganisms. 相似文献
782.
Shun Kawakubo Shuzo Murakami Toshiharu Ikaga Yasushi Asami 《Building Research & Information》2018,46(5):528-539
ABSTRACTThe United Nations’ (UN) sustainable development goals (SDGs), the core of the 2030 Agenda for Sustainable Development and the UN Paris Agreement, were adopted in 2015. Involvement of not only national governments but also all other stakeholders including local governments is important to promote sustainable development and to achieve the goals. The question arises, therefore, of what methods should be used to best implement and assess sustainability issues at a local level. In this light, a new version of Comprehensive Assessment System for Built Environment Efficiency (CASBEE), CASBEE for Cities, is introduced for assessing the sustainability of cities and communities around the world based on SDG indicators and greenhouse gas (GHG) emissions. The tool allows users to understand the sustainability of cities and communities based on quality (Q) and environmental load (L) perspectives. The sustainability assessments show that cities in developed countries tend to have good grades for Q, but bad grades for L, while cities in developing countries tend to have the opposite trend. This will assist cities and communities in both developed and developing countries to understand urgent problems and to identify effective solutions for sustainable development. 相似文献
783.
防屈曲支撑的研究进展及其工程应用 总被引:3,自引:0,他引:3
简要介绍了防屈曲支撑的组成及工作机理,详细介绍了防屈曲支撑的发展和近年来中国学者在理论研究和类型创新方面取得的研究成果;着重讨论了三重钢管、端部铰式、中部接触环式等新型防屈曲支撑的性能;最后给出了防屈曲支撑在中国的应用情况.研究结果表明:防屈曲支撑以其良好的耗能性能会有很好的发展潜力;防屈曲支撑应该向着低屈服点设计、适用于大跨结构、便于安装等方向发展,并在实际工程中推广应用. 相似文献
784.
N. OtoS. Oshita S. KawagishiY. Makino Y. KawagoeM.I. Al-Haq S. ShinozakiN. Hiruma 《Journal of food engineering》2012,110(1):9-17
To develop a real-time and non-destructive sanitation monitoring at a meat processing plant, UV-Vis reflectance spectrum analysis was applied. The sample was the lean part of a pork loin. The UV-Vis reflectance spectra and the factors of microbial contamination (i.e. plate count and ATP content) on the pork meat surface were measured for 3 or 4 days. The 2nd derivative of reflectance at 318 and 578 nm gave a high correlation with log10(plate count) or log10(ATP content), because the reflectance spectrum at 318 nm is probably related to ATP absorption and that at 578 nm is related to myoglobin pigments. Moreover, Partial least squares regression (PLSR) was developed and log10(plate count) and log10(ATP content) were predicted from the 2nd derivative of reflectance. The determination coefficients (R2) for calibration were 0.95-0.99. These results indicate the potential of utilizing UV-Vis reflectance spectrum analysis for cleanness assessment. 相似文献
785.
Yuan B Yokochi N Yoshikane Y Ohnishi K Yagi T 《Journal of Bioscience and Bioengineering》2006,102(6):504-510
The gene (mlr6788) of a nitrogen-fixing symbiotic bacterium Mesorhizobium loti MAFF303099 has been identified as a gene coding for 2-methyl-3-hydroxypyridine-5-carboxylic acid dioxygenase (MHPCO), the seventh enzyme in degradation pathway I for pyridoxine, a free form of vitamin B(6). The gene was cloned and overexpressed in Escherichia coli cells co-transformed with chaperonin genes. The homogeneous recombinant enzyme showed similar enzymatic properties to the enzyme from Pseudomonas sp. MA-1. MHPCO was essential for the assimilation of pyridoxine in M. loti, but not for its growth in a nutrient-rich medium. From the infection experiment of a symbiotic plant Lotus japonicus with an M. loti mlr6788 gene disruptant, MHPCO was demonstrated to be dispensable for at least nodule formation on roots of seedlings in symbiosis. 相似文献
786.
787.
Makino S Ikegami S Kano H Sashihara T Sugano H Horiuchi H Saito T Oda M 《Journal of dairy science》2006,89(8):2873-2881
The extracellular polysaccharides (EPS) produced by lactic acid bacteria (LAB) are associated with the rheology, texture, and mouthfeel of fermented milk products, including yogurt. This study investigated the immunomodulatory effects of EPS purified from the culture supernatant of Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) OLL1073R-1. The crude EPS were prepared from the culture supernatant of L. bulgaricus OLL1073R-1 by standard chromatographic methods, and were fractionated into neutral EPS and acidic EPS (APS). Acidic EPS were further fractionated into high molecular weight APS (H-APS) and low molecular weight APS (L-APS). High molecular weight APS were shown to be phosphopolysaccharides containing D-glucose, D-galactose, and phosphorus. Stimulation of mouse splenocytes by H-APS significantly increased interferon-γ production, and, moreover, orally administered H-APS augmented natural killer cell activity. Oral administration of yogurt fermented with L. bulgaricus OLL1073R-1 and Streptococcus thermophilus OLS3059 to mice showed a similar level of immunomodulation as H-APS. However, these effects were not detected following administration of yogurt fermented with the starter combination of L. bulgaricus OLL1256 and S. thermophilus OLS3295. We conclude from these findings that yogurt fermented with L. bulgaricus OLL1073R-1, containing immunostimulative EPS, would have an immunomodulatory effect on the human body. 相似文献
788.
We have improved electrical characteristics of a film bulk acoustic wave (BAW) resonator that features the injection of H2O gas into a process chamber. The preferred crystallinity of piezoelectric ZnO film was obtained by RF sputtering at a high H2O partial pressure 1.5×10−4 Pa. The effective electromechanical coupling coefficient () of the BAW resonator remarkably goes up from 1.8% to 4.7% for which the corresponding H2O partial pressures are 2.7×10−5 and 1.5×10−4 Pa. Injection of H2O during the deposition process contributes to the improvement of crystallinity of ZnO thin film and the electrical characteristics of the BAW resonator. 相似文献
789.
Although the number of cheese manufacturing units in Hokkaido had increased every year and exceeds 60, many of these units are small-scale processors. We examined the cheese produced in Hokkaido for the presence of Staphylococcus aureus for 3 years after 2002. During the study period, S. aureus was isolated from 38 cheese samples: 3.6 to 9.2% of the total cheese samples examined and 13.0 to 20.0% of the total mozzarella-type cheese samples. The largest population of S. aureus was 2.0 x 10(4) CFU/g. The isolated S. aureus strains were subjected to PCR analysis to look for seven se genes. Of the 38 isolates, 20 did not possess the se gene, but the remaining 13 isolates had seg and sei genes. No enterotoxins were detected in the cheese samples analyzed with a commercial kit. 相似文献
790.
To determine the effects of a vegetarian diet with avocado as a source of monounsaturated fat on serum lipids, thirteen patients with phenotype II (twelve with IIa and one with IIb) dyslipidemia were included in a prospective, transversal and comparative study in which three four-week diets randomly assigned were assessed. One vegetarian diet (ALVD) was composed of 70% carbohydrates, 10% proteins and 20% lipids. Another was composed of 60% carbohydrates, 10% proteins and 30% lipids, 75% of which was supplied by avocado (AVD). A third diet was an avocado-added free diet (FDWA). Body weight, body mass index (BMI), and serum lipids (total cholesterol (TC), high (HDL) and low density lipoprotein (LDL) cholesterol and triglycerides (TG)) were evaluated. AVD produced a significant decrease in LDL. ALVD did not change TC and LDL, while FDWA increased them slightly. The three diets reduced TG levels, but only ALVD did so significantly. All three diets reduced HDL levels, particularly ALVD, which produced the greatest reduction. Low-fat, carbohydrate-rich vegetarian diets may be harmful to hypercholesterolemic patients. The avocado addition to a vegetarian diet does not correct these undesirable effects. To obtain beneficial effects on lipid profile with avocado, lower amounts of carbohydrates and polyunsaturated fatty acids are probably needed. 相似文献