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121.
E.A. Ellebracht A. Castillo L.M. Lucia R.K. Miller G.R. Acuff 《Journal of food science》1999,64(6):1094-1099
Beef trimmings from young or mature beef cattle were obtained commercially. Trimmings within age type then were inoculated with about 6.0 log10 CFU/mL of rifampicin-resistant. Escherichia coli O157:H7 and Salmonella typhimurium (ATCC 13311) were randomly assigned to 1 of 3 treatments (control; 95 °C hot water alone, or with 2% L-lactic acid). After treatment, trimmings were ground, held for 0, 14, 28, or 42 d in chub packages at 4 °C, and total aerobic plat counts, E. coli O157:H7, and S. typhimurium counts were determined. Non-inoculated trimmings were also treated and samples were evaluated for pH, fat, moisture, TBA, meat color by colorimeter, and meat color, and odor by trained sensory panels. Trimmings treated with water or hot water plus lactic acid reduced levels of E. coli O157:H7 and S. typhimurium and tended to be darker after treatment. Meat odor in the final product was not affected by treatment. 相似文献
122.
Heloiza Vieira Rodrigues Pereira Karina Peixoto Saraiva Lucia Maria Jaeger Carvalho Leonardo Rodrigues Andrade Cristiana Pedrosa Anna Paola Trindade Rocha Pierucci 《Food research international (Ottawa, Ont.)》2009,42(1):115-121
This study evaluated the use of pea (Pisum sativum) and cowpea (Vigna unguiculata) protein isolates (PPI and CPI) in the microencapsulation of ascorbic acid (AA), by spray drying. PPI and CPI were used pure or mixed with maltodextrin (M) as wall materials of AA. The process yield was improved from 66% to 86% by the addition of M (CPI/M and PPI/M); also, AA particles yield was 79%. The AA retention from the drying process was higher in PPI/M (69%) than in CPI/M (66%), and this was attributed to PPI proteolysis profile, demonstrated by the SDS–PAGE electrophoresis. Scanning electron microscopy revealed that AA particles were similarly spherical and shriveled. Mean particle sizes of PPI/M/AA and CPI/M/AA were 7 and 8 μm, respectively. This study showed the exploration of protein isolates from legumes in the development of a microparticulate system containing AA with great potential for use in human health. 相似文献
123.
124.
This paper describes a study on the contribution of linguistically-informed features to the task of quality estimation for machine translation at sentence level. A standard regression algorithm is used to build models using a combination of linguistic and non-linguistic features extracted from the input text and its machine translation. Experiments with three English–Spanish translation datasets show that linguistic features on their own are not able to outperform shallower features based on statistics from the input text, its translation and additional corpora. However, further analysis suggests that linguistic information can be useful to produce better results if carefully combined with other features. An in-depth analysis of the results highlights a number of issues related to the use of linguistic features. 相似文献
125.
126.
Antonio Lopez Martin Jose Maria Algueta Miguel Lucia Acosta Jaime Ramírez‐Angulo Ramón Gonzalez Carvajal 《ETRI Journal》2011,33(3):393-400
A systematic approach for the design of two‐stage class AB CMOS unity‐gain buffers is proposed. It is based on the inclusion of a class AB operation to class A Miller amplifier topologies in unity‐gain negative feedback by a simple technique that does not modify quiescent currents, supply requirements, noise performance, or static power. Three design examples are fabricated in a 0.5 µm CMOS process. Measurement results show slew rate improvement factors of approximately 100 for the class AB buffers versus their class A counterparts for the same quiescent power consumption (< 200 µW). 相似文献
127.
José A. Souto Dr. Rosaria Benedetti Katharina Otto Marco Miceli Rosana Álvarez Prof. Dr. Lucia Altucci Prof. Dr. Angel R. de Lera Prof. Dr. 《ChemMedChem》2010,5(9):1530-1540
A series of N‐(4‐cyano‐3‐trifluoromethyl‐phenyl)‐2‐ethoxy‐6‐alkyl (and alkenyl) benzamides related to the anacardic acid derivative CTPB have been prepared from 2,6‐dihydroxybenzoic acid with a Suzuki coupling and addition of the anion of 4‐cyano‐3‐trifluoromethylphenylamine to a benzodioxinone as the key steps. In U937 cells, these analogues, in particular 7 c , 7 d , 7 f and 7 j , induced cell‐cycle arrest in the G1 phase, caused apoptosis in about 20 % of the cells, and increased the acetylation levels of H3. These activities correlate with the enzymatic activation of histone lysine acetyltransferases (KATs): CBP and PCAF. 相似文献
128.
Miklós Serényi Cesare Frigeri Zsolt Szekrényes Katalin Kamarás Lucia Nasi Attila Csik Nguyen Quoc Khánh 《Nanoscale research letters》2013,8(1):84
Differently hydrogenated radio frequency-sputtered a-Si layers have been studied by infrared (IR) spectroscopy as a function of the annealing time at 350°C with the aim to get a deeper understanding of the origin of blisters previously observed by us in a-Si/a-Ge multilayers prepared under the same conditions as the ones applied to the present a-Si layers. The H content varied between 10.8 and 17.6 at.% as measured by elastic recoil detection analysis. IR spectroscopy showed that the concentration of the clustered (Si-H)n groups and of the (Si-H2)n (n ≥ 1) polymers increased at the expense of the Si-H mono-hydrides with increasing annealing time, suggesting that there is a corresponding increase of the volume of micro-voids whose walls are assumed from literature to be decorated by the clustered mono-hydride groups and polymers. At the same time, an increase in the size of surface blisters was observed. Also, with increasing annealing time, the total concentration of bonded H of any type decreases, indicating that H is partially released from its bonds to Si. It is argued that the H released from the (Si-H)n complexes and polymers at the microvoid surfaces form molecular H2 inside the voids, whose size increases upon annealing because of the thermal expansion of the H2 gas, eventually producing plastic surface deformation in the shape of blisters. 相似文献
129.
Koffi L Dagnon Hua H Chen Lucia H Innocentini‐Mei Nandika A D'Souza 《Polymer International》2009,58(2):133-141
BACKGROUND: The thermomechanical performance of poly[(3‐hydroxybutyrate)‐co‐(3‐hydroxyvalerate)] (PHBV) is associated with its crystallization. Enhanced nucleation using a stearate‐functionalized synthetic layered double hydroxide (LDH) presents a potential solution. RESULTS: PHBV crystallization varied with concentration of LDH. At lower LDH concentration, thermal history‐induced cold crystallization was present. The extent of this order–disorder transition decreased with increasing LDH concentration and was completely eliminated at 7 wt% LDH. PHBV did not have a melt recrystallization peak but the introduction of LDH resulted in an increasingly pronounced melt recrystallization with increasing LDH concentration. Polarized optical microscopy coupled with differential scanning calorimetry and wide angle X‐ray diffraction (WAXD) analysis indicated increased lamella thickness in the nanocomposites compared to pure PHBV. WAXD and transmission electron microscopy showed that the nanocomposites had an intercalated but aggregated dispersion. CONCLUSION: The concentration of nanofiller provides unique effects in PHBV. Mechanical performance was found to scale with composition as determined using dynamic mechanical analysis and tensile testing. Copyright © 2008 Society of Chemical Industry 相似文献
130.
The microstructure of a friction stir welded magnesium alloy AM50 was examined by means of optical light microscopy. The chemical composition, particularly the iron content, and morphology of the oxide film were analyzed and discerned via auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS). Corrosion behaviour of the welds and base materials were investigated by virtue of neutral salt spray tests and potentiodynamic polarization measurements in conventional cells and in a mini cell. The results demonstrate that minor increases in iron concentration as might be speculated to occur as a consequence of tool/work piece interaction during the welding process on the corrosion resistance of the weld can be ignored. The corrosion morphology was predominantly influenced by the distribution of the Mg17Al12 phase. Here, it was also found that the corrosion resistance of the friction stir weld varied in response to changes in the joint microstructure. 相似文献