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881.
882.
Jayendra K. Amamcharla Suranjan Panigrahi Catherine M. Logue Martin Marchello Julie S. Sherwood 《Sensing and Instrumentation for Food Quality and Safety》2010,4(1):1-12
Detection of beef contamination from harmful pathogens will be helpful in protecting the consumer safety and controlling the outbreaks. In this paper, the potential of Fourier transform infrared spectroscopy (FTIR) was investigated to discriminate the Salmonella contaminated packed beef. A suitable headspace sampling system was designed and used to collect the headspace volatiles from the packed meat to the FTIR gas cell. Spectral signatures of headspace volatiles of meat packages were used to classify the packed meat samples as contaminated or not. FTIR spectrum was divided into several regions in order to reduce the dimensionality as well as to select the regions based on the absorbance properties of various volatiles present in headspace of meat package. Principal component analysis was performed on the entire spectrum (4000–500 cm−1) as well as on the selected sub-regions of entire spectrum. Two statistical classification techniques (linear and quadratic discriminate analysis) were used to develop classification models. The statistical models were validated using bootstrap cross validation technique. The total average classification accuracies were evaluated in terms of coefficient of variance (% CV). Based on the mean of total average classification accuracies and its % CV calculated from five similarly conducted experiments, it was found that the statistical models developed on a part of the spectra (500–850 cm−1) and full spectra (4000–500 cm−1) can be used as potential classification models for non-destructive discrimination of Salmonella contaminated packed beef samples from uncontaminated ones. These results need to be further validated on dataset with larger sample size. 相似文献
883.
Alcohol advertisements may influence impulsive, risky behaviors indirectly, via automatically-activated attitudes toward alcohol. Results from an experiment in which participants were exposed to either four alcohol advertisements, four control advertisements, or four drunk driving public service advertisements, suggested that alcohol advertisements had more measurable effects on implicit, than on explicit attitude measures. Moreover, there were significant indirect paths from alcohol advertisement exposure through automatically-activated alcohol attitudes on willingness to engage in risky alcohol-related behaviors, notably drinking and driving. A mechanism that may explain how these advertisements activate automatic, non-deliberative alcohol attitudes was investigated. Associative evidence was found supportive of an evaluative conditioning mechanism, in which positive responses to an alcohol advertisement may lead to more positive automatically-activated attitudes toward alcohol itself. 相似文献
884.
Effects of atropine on blood plasma amino acid profile and on the yields and concentration of milk components were investigated in 12 Friesian cows in early lactation. Cows were housed indoors and fed with cut pasture ad libitum. Each cow received four treatments over 12 d during a replicated 4 x 4 Latin square experiment. Treatments were: control (saline); low dose (L; 30 microg atropine/kg body weight (BW)); medium dose (M; 40 microg atropine/kg BW); and 2 x L dose, 2 h apart (2 x L). On each of four treatment days, cows were milked at about 7.00, after which treatments were administered by subcutaneous injection. Cows were milked again at 2 h, 6 h and 10 h after injection. Milk samples were collected at each milking. Immediately after the 2 h milking, blood samples were drawn from each cow and the second injection was given for the 2 x L treatment. Atropine reduced hourly milk yield, and concentrations and hourly yields of total protein, casein, whey protein, alpha-casein, beta-casein, kappa-casein, beta-lactoglobulin and alpha-lactalbumin, but by differing amounts. Milk concentrations of bovine serum albumin and immunoglobulin G were increased by atropine, and overall yields of these proteins were mostly unchanged. Atropine lowered concentrations of most, but not all, amino acids in blood plasma, with essential amino acids reduced more than non-essential amino acids. Concentrations of alpha-amino N in whole blood, and glucose and insulin in blood plasma, fell after atropine injection. There was no difference between the L and M doses of atropine, but the 2 x L dose had greater effects on milk composition than the single doses. For yields of milk and milk components, the effect of the 2 x L dose was also more persistent. The results highlight the differential synthesis of individual milk proteins, and suggest that atropine might be useful for evaluating the mechanisms regulating milk protein composition. 相似文献
885.
Catherine Knight 《河流研究与利用》2019,35(10):1622-1628
This paper examines how attitudes towards rivers in Aotearoa New Zealand have evolved since the country's settlement by Europeans, two centuries ago. For most of our postcolonial history, rivers have been viewed as something to be controlled and managed—even “improved.” But today, rivers are increasingly being recognized as embodying a broad range of values from the ecological to the spiritual—not simply as a “channel of water” that can be exploited for human ends. Although much of this evolving understanding stems from the advance in scientific knowledge, much too has its roots in our collective past. 相似文献
886.
This review summarizes the life and work of Louis-Camille Maillard, the most worldwide renowned French biochemist of the 20th century. It focuses on the main events in Maillard's life and the reaction sugar-amino acids in his work, and offers an overview of the Maillard reaction in vitro and in vivo. 相似文献
887.
Remediating chlorinated solvent source zones 总被引:2,自引:0,他引:2
Stroo HF Unger M Ward CH Kavanaugh MC Vogel C Leeson A Marqusee J Smith BP 《Environmental science & technology》2003,37(11):224A-230A
888.
Catherine Glover 《Costume》2013,47(1):139-140
AbstractKeynote address presented at the Costume Society Symposium Oxford, July, 2001 相似文献
889.
Albert Ribas-Agustí Barbara Gouble Sylvie Bureau Jean-François Maingonnat Jean-Marc Audergon Catherine M. G. C. Renard 《Food and Bioprocess Technology》2017,10(4):662-673
Quality of canned apricots is seriously compromised by the loss of their flesh firmness during pasteurization. This work conducted a comprehensive characterization of the biochemical properties of raw apricots, as well as of the tissue softening during pasteurization using a multimethodology approach. Biochemical and textural results were analyzed to seek possible correlations, with the aim to elucidate which properties could be used as indicators in raw fruit for obtaining pasteurized products with better texture. There were large effects of cultivar, ripening stage, and intra-fruit zone on the biochemical and textural properties of apricots. The titratable acidity, amongst ethylene production, soluble solid content, and pectinolytic enzyme activities, was the biochemical property that correlated more robustly to the loss of texture. It had significant correlation coefficients of ?0.9 and 0.5 with firmness of pasteurized fruit and loss of firmness, respectively. We propose titratable acidity to be used as indicator for raw material selection and/or to be modulated during apricot food processing. 相似文献
890.
Susana M Cardoso Sylvain Guyot Nathalie Marnet Jos A Lopes‐da‐Silva Artur MS Silva Catherine MGC Renard Manuel A Coimbra 《Journal of the science of food and agriculture》2006,86(10):1495-1502
Analysis of a purified fraction from acetone extracts of olive pulp and pomace by electrospray ionisation tandem mass spectrometry (ESI‐MSn) showed the presence of oleuropein oligomers, whose occurrence has not been reported previously in the literature. The main ionic species (m/z 1613) in the ESI‐MS spectrum was an oleuropein trimer containing three linkages through the hydroxytyrosol backbone. In both samples, oleuropein dimers (m/z 1075), trimers comprising two hydroxytyrosol linkages (m/z 1615), tetramers (m/z 2153) and pentamers (m/z 2691) were also detected by MS. The occurrence of oleuropein oligomers was also observed by nuclear magnetic resonance (NMR). 13C, 13C distortionless enhancement by polarisation transfer DEPT 90, 13C DEPT 135, gHSQC (heteronuclear single quantum coherence) and gHMBC (heteronuclear multiple bond coherence) spectra showed all carbon and proton resonances of oleuropein with the exception of the low‐mobility and asymmetric signals of the aromatic rings. Since mature olives were used in this study, it is possible that the disappearance of oleuropein that has been described to occur with the olive fruit maturation, could be associated with the formation of phenolic oligomers together with lower‐molecular‐weight compounds resulting from its degradation. Copyright © 2006 Society of Chemical Industry 相似文献