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91.
Sub-micrometer powder (100–150 nm diameter) of Yb-doped yttrium oxide was obtained, for the first time, by microwave-assisted polyol (diethylene glycol, DEG) method. This method is based on fast and homogeneous increase of temperature, due to the microwave heating, and on addition of the hydrolysing agent (water) at high temperature. This promotes a fast nucleation followed by a controlled growth of nuclei. Different procedures were used to process the as-synthesized powders. In some cases washing by ultrapure water was used to dissolve nitrate and DEG by-products, this treatment allowed the use of a lower calcination temperature (150–200 °C less) to obtain the crystalline phase. Analysis of the calcined powder showed different levels of structures: from nanocrystal (10–15 nm), to primary particles (100–150 nm), to micrometer soft aggregates (2–4 μm). The microwave-assisted polyol method resulted an easy way to dope yttria with the desired amount of Yb3+. This work was carried out in order to prepare particles to be used as rare-earth doped Y2O3 and YAG polycrystalline transparent ceramic for laser source applications.  相似文献   
92.
The aim of this work was to study the influence of a diet with probiotic bacteria on the lipid composition of different tissues from Iberian pigs. Cholesterol and fatty acid profiles were measured in liver, subcutaneous fat, and Serratus ventralis muscle samples. Feeding Iberian pigs a mixture of probiotic microorganisms for 45 days prior to slaughter affected the tissue composition. The feeds of the control and probiotic groups were identical except for the added Bacillus licheniformis and Bacillus subtilis (1.28 × 109 cfu/kg feed) in the feed of the probiotic group. The diet with probiotics significantly affected the fatty acid profile of liver, subcutaneous fat and Serratus ventralis muscle samples, but no significant differences were found for the cholesterol content. The livers of the probiotic group contained lower levels of n‐6 fatty acids and higher levels of n‐3 fatty acids. The subcutaneous fat contained lower levels of n‐6 fatty acids. Serratus ventralis muscles from the probiotic group contained a significantly higher percentage of oleic acid than those of the control group. Practical applications: This study deals with the effect of the addition of probiotic bacteria to the diet of pigs on both the cholesterol and fatty acid content. B. subtilis and B. licheniformis can be used in pig feed (Regulation EC no. 2148/2004), but there are no studies about their effects on fresh meat or other tissues, particularly regarding the fat composition. Thus, it is interesting to study how feeding these microorganisms affects the different tissues. Including these microorganisms in the basic diet could serve as a strategy to modify the fat composition and to obtain healthier products from pigs.  相似文献   
93.
Waste generated in ceramic tiles manufacturing is not usually recycled inside the productive plant, but rather disposed to landfill. This paper deals with ceramic residues from polishing and glazing processes, as constituents for innovative blended cements. New binders made up of 75% CEM I 52.5 R and 25% residues were chemically, physically, and mechanically characterized with reference to EN 197-1 requirements and the results compared with ordinary Portland cement. Mechanical strength development and microstructure of the relevant mortar have been investigated up to 90 days of curing, and the behavior of polishing and glazing residues as cement constituents is reported.  相似文献   
94.
The use of peptide receptors as targets for tumor‐selective therapies was envisaged years ago with the findings that receptors for different endogenous regulatory peptides are overexpressed in several primary and metastatic human tumors, and can be used as tumor antigens. Branched peptides can retain or even increase, through multivalent binding, the biological activity of a peptide and are very resistant to proteolysis, thus having a markedly higher in vivo activity compared with the corresponding monomeric peptides. Oligo‐branched peptides, containing the human regulatory peptide neurotensin (NT) sequence, have been used as tumor‐specific targeting agents. These peptides are able to selectively and specifically deliver effector units, for cell imaging or killing, to tumor cells that overexpress NT receptors. Results obtained with branched NT conjugated to different functional units for tumor imaging and therapy indicate that branched peptides are promising novel multifunctional targeting molecules. This study is focused on the role of the releasing pattern of drug‐conjugated branched NT peptides. We present results obtained with oligo‐branched neurotensin peptides conjugated to 6‐mercaptopurin (6‐MP), combretastain A‐4 (CA4) and monastrol (MON). Drugs were conjugated to oligo‐branched neurotensin through different linkers, and the mode‐of‐release, together with cytotoxicity, was studied in different human cancer cell lines. The results show that branched peptides are very promising pharmacodelivery options. Among our drug‐armed branched peptides, NT4–CA4 was identified as a candidate for further development and evaluation in preclinical pharmacokinetic and pharmacodynamic studies. This peptide–drug exhibits significant activity against pancreas and prostate human cancer cells. Consequently, this derivative is of considerable interest due to the high mortality rates of pancreas neuroendocrine tumors and the high incidence of prostate cancer.  相似文献   
95.
Differential scanning calorimetry (DSC) was used to study the 7S and 11S globulin fractions extracted from lupin seed (Lupinus luteus) flour. In agreement with previous work on other lupin species, the isolate showed three denaturation peaks compared to the two observed with soy. By comparison with the isolated globulin fractions, the denaturation peaks at the two higher temperatures in the lupin isolate were assigned to the 11S and 7S globulins. The denaturation temperature of the lupin 7S globulin was about 10 K higher than that for the corresponding soy globulin, whereas the values for the 11S globulin were similar. All globulins displayed increasing thermal stability with decreasing moisture contents. Possible reasons for the differences in behaviour of soy and lupin protein isolates are discussed.  相似文献   
96.
The presence or absence of filbertone in 21 admixtures of olive oil with virgin and refined hazelnut oils obtained using various processing techniques from different varieties and geographical origins was evaluated by solid phase microextraction and multidimensional gas chromatography (SPME–MDGC). The obtained results showed that the sensitivity achievable with the proposed procedure was enough to detect filbertone and, hence, to establish the adulteration of olive oil of different varieties with virgin hazelnut oils in percentages of up to 7%. The very low concentrations in which filbertone occurs in some refined hazelnut oils made difficult its detection in specific admixtures. In any case, the minimum adulteration level to be detected depends on the oil varieties present in the adulterated samples. In the present study, the presence of R- and S-enantiomers of filbertone could be occasionally detected in olive oils adulterated with 10–20% of refined hazelnut oil.  相似文献   
97.
98.
A statistical comparison of the spiral plate count (SPLPC) and the standard plate count (SPC) methods for enumeration of microorganisms in raw goat's milk cheese throughout its manufacturing and ripening was carried out. Enumeration of mesophiles, lactic acid bacteria (presumptive lactococci, presumptive leuconostocs, and presumptive lactobacilli), Micrococcaceae, Enterobacteriaceae, and molds and yeasts was carried out for milk, curd, and 2-, 5-, 10-, 17-, and 27-day-old cheeses. Average counts for the SPLPC and SPC methods differed by less than half of a log cycle for all microbial groups studied (range of difference, -0.1386 [mesophiles] to +0.4397 [presumptive lactobacilli]). The results of the SPLPC method compared favorably with the results of the SPC procedure for mesophiles, presumptive lactococci, presumptive leuconostocs, Enterobacteriaceae, and molds and yeasts (the variance between replicate platings was close to 0.005, and correlation coefficients were >0.9). Correlation coefficients were lower for Micrococcaceae (r = 0.824) and presumptive lactobacilli (r = 0.670). Analysis of variance showed that the plating method was a significant factor (P < 0.05) for presumptive lactobacilli counts. In general, results from the SPLPC method compared favorably with results from SPC procedure in the enumeration of microorganisms in goat cheese throughout its manufacturingand ripening processes. However, the suitability of the SPLPC method depends mainly on the microbial group studied.  相似文献   
99.
Pork skin and muscle tissue were washed with water at temperatures from 25 to 80 degrees C. Water temperatures of 65 and 80 degrees C resulted in greater population reductions of Enterobacteriaceae on pork muscle tissue than lower water temperatures. There was no observable effect of water temperature on population reductions of Enterobacteriaceae on pork skin. Water temperatures of 55, 65, and 80 degrees C reduced the populations of Enterobacteriaceae on inoculated scalded carcasses processed in a university abattoir by 1 to 1.5 log/cm2. Following the water wash with an organic acid rinse resulted in further numerical reductions in populations, although these were not statistically different from the water wash alone. The jowls of both scalded and skinned carcasses processed in a commercial establishment were directly inoculated with a fecal material slurry and then processed with organic acid rinsing only, hot water washing only, or a combination of hot water washing followed by organic acid rinsing. The hot water and acid treatment reduced the populations of mesophilic aerobic bacteria and Escherichia coli by approximately 2 log cycles on both scalded and skinned hog carcasses. The combined treatment resulted in 60% of the scalded carcasses and 40% of the skinned carcasses with undetectable levels of E. coli after direct fecal inoculation of the carcasses. Hot water washing followed by organic acid rinsing can significantly improve the microbiological quality of pork carcasses.  相似文献   
100.
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