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排序方式: 共有412条查询结果,搜索用时 31 毫秒
21.
The aim of this study was to evaluate the usefulness of the Rapid Visco Analyser (RVA) instrument combined with pattern recognition methods as tools to differentiate commercial barley samples from two South Australian localities and three harvests. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and stepwise discriminant analysis were applied to classify samples based on the RVA profiles using full cross validation (leave-one-out) as the validation method. The PLS-DA models correctly classify 96.3 and 97.8 % of the barley samples according to harvest and locality, using the profiles generated by the RVA instrument. Analysis and interpretation of the eigenvectors and loadings from the PCA or PLS-DA models developed verified that the RVA profiles contain relevant information related to starch pasting properties that allows sample classification. These results suggest that RVA coupled with PLS-DA holds necessary information for a successful classification of barley samples sourced from different localities and harvests. 相似文献
22.
Sijing Li Kerry L. Wilkinson Daniel Cozzolino 《Sensing and Instrumentation for Food Quality and Safety》2014,8(4):356-361
Near infrared (NIR) reflectance spectroscopy combined with chemometrics was used to classify toasted and untoasted oak wood shavings sourced from two countries (France and USA). Oak wood shaving samples (n = 96) were scanned in the NIR region (680–2,500 nm) using a monochromator instrument operating in reflectance mode. Principal component analysis, partial least squares discriminant analysis (PLS-DA) and linear discriminant analysis (LDA) were used to classify the samples according to their country of origin and level of toasting. Full cross validation (leave-one-out) was used as the validation method when classification models were developed. Correct classification rates of 83, 87 and 100 % for samples sourced from USA, France and toasted treatment were obtained using PLS-DA. For LDA, correct classification rates of 80.4, 85 and 100 % were achieved for samples sourced from USA, France and toasted treatment, respectively. These results demonstrated the ability of NIR spectroscopy to discriminate between oak wood shavings sourced from two different countries and two levels of toasting. 相似文献
23.
Melis Maria Rosaria; Succu Salvatora; Spano Maria Sabrina; Argiolas Antonio 《Canadian Metallurgical Quarterly》2000,114(4):849
In male rats, noncontact erections occur concomitantly with an increase in NO?- and NO?- in the paraventricular nucleus of the hypothalamus (PVN). In the present study, both responses were reduced by the blockade of PVN excitatory amino acid receptors by dizocilpine, (+)-MK-801(1 and 5 μg), but not by 6-cyano-7-nitro-quinoxaline-2,3-dione (5 μg) or (±)-2-amino-4-phosphono-butanoic acid (5 μg). Also ineffective when injected into the PVN were the dopamine antagonists SCH 23390 (5 μg), S(+)-raclopride (10 μg), and cis-flupenthixol (10 μg), and the oxytocin antagonist d(CH?)?Tyr(Me)2-Orn?-vasotocin (1 μg). However, when the last was given into the lateral ventricles, it reduced noncontact erections without modifying NO?- and NO?- increases. These results suggest that excitatory amino acid transmission increases in the PVN during noncontact erections. This may contribute to increased NO production in the PVN, and it may activate oxytocin neurons mediating this sexual response. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
A Filippelli C Esposito M Falciani C Costa A Cozzolino F Rossi R Porta 《Canadian Metallurgical Quarterly》1997,60(6):403-411
This study presents the investigation of the relations between sensation seeking (41) and anhedonia in 80 subjects who practice a risk taking sport, bengy jump. These relations were examined according to different variables which characterize the practice of bengy jump: the total number of previous jumps and the motivations to jump (1. personal motivation, 2. professional motivation--working in the jumping organization, and 3. group motivation--for example being leaded to jump by friends). We also assessed the use of psychoactive substances. All jumpers (men and women) have higher scores than control subjects in Thrill and adventure seeking dimension. In men, the more the subjects score on this dimension, the less they score on the physical anhedonia scale (8). In women, Experience Seeking and Boredom Susceptibility dimensions are positively correlated with physical anhedonia and with the number of jumps. Moreover, women with personal motivation are those who score the highest on Thrill and Adventure Seeking and Boredom Susceptibility dimensions. These results suggest that in women, sensation seeking through bengy jumping may be linked to a boredom tendency and driven by a need to compensate for a difficulty in experiencing emotions and sensations from common and mundane stimuli. In men, high frequency of bengy jumping was negatively related to the use of psychoactive substances, suggesting that bengy jump, in a compulsive form recalling an addictive behavior, is a specific and preferential way of stimulation seeking. 相似文献
25.
Albenzio M Santillo A Caroprese M Marino R Centoducati P Sevi A 《The Journal of dairy research》2005,72(4):447-455
The influence of three different ventilation regimens on air pollution in sheep houses and on the quality of ewe milk and of Canestrato Pugliese cheese was investigated during the summer season. The experimental treatments were low ventilation regimen (VR=35 m3/h per ewe) split in 30-min ventilation cycles (LOV-30); moderate ventilation regimen (VR=70 m3/h per ewe) split in 30-min ventilation cycles (MOV-30); moderate ventilation regimen (VR=70 m3/h per ewe) split in 60-min ventilation cycles (MOV-60). The LOV-30 milk had higher microbial load and bulk milk somatic cell count (BMSCC) and resulted in a weaker casein matrix in the curd compared with the MOV-30 and MOV-60 treatments. At 45 d of ripening, the LOV-30 cheeses had a lower casein content and higher non-casein nitrogen (NCN) and water-soluble nitrogen (WSN) contents than the MOV-30 and MOV-60 cheeses. Urea-polyacrylamide gel electrophoresis (urea-PAGE) of the pH 4.6-soluble N extract showed that the MOV-60 cheeses had fewer bands derived from casein (CN) hydrolysis than the LOV-30 or MOV-30 cheeses, despite its having exhibited the highest plasmin (PL) activity levels. Our results suggest that the ventilation regimen is critical in dairy sheep housing for optimizing the hygienic quality of ewe milk and the proteolytic processes occurring in Canestrato Pugliese cheese during ripening. 相似文献
26.
27.
Protocatechuic acid activates key components of insulin signaling pathway mimicking insulin activity
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28.
Daniela Campaniello Antonio Bevilacqua Barbara Speranza Milena Sinigaglia Maria Rosaria Corbo 《Food and Bioprocess Technology》2018,11(6):1139-1148
The topic of this paper is the investigation of the antibacterial effect of ultrasound (US) towards Salmonella enterica in a rice beverage. The beverage was inoculated at different levels (8 and 5 log CFU/mL) and US-treated; then, a challenge test under refrigeration was carried out. The maximum net power of the equipment was 130 W; the treatment was carried out at 40–100% of the net power, for 2–10 min; the pulse was set to 2–10 s. For both the inoculum levels, power and time were the most important factors for the antimicrobial effect towards S. enterica. The combinations resulting in the highest inactivation of the pathogen were tested during the challenge test at 4 °C, and in some combinations, S. enterica remained below the detection limit for 13 days. 相似文献
29.
Antonio Bevilacqua Mariangela Gallo Maria Rosaria Corbo Milena Sinigaglia 《International Journal of Food Science & Technology》2013,48(7):1366-1370
The main goal of this research was the evaluation of the survival of Enterobacter cloacae in a model olive brine. Two different assays were run; the first experiment assessed the viability of the target in brines containing NaCl (6–12%) and p‐coumaric acid (0.0–0.05%), adjusted to different pHs (4–10) and stored at 10–30 °C for 9 days. The death rate and cell levels at selected times were modelled with a polynomial equation to highlight the individual and interactive effects of NaCl/p‐coumaric acid/pH/temperature. Then, a second experiment was run for 3 months (temperature, 10 °C; pH, 4.5–5.5; NaCl, 6–8%). The survival of E. cloacae was affected mainly by pH, then by salt and temperature; however, the significance of the variables changed within the time, as salt and temperature acted in a significant way only after 1 day. 相似文献
30.
Selection of promising lactic acid bacteria as starter cultures for sourdough: using a step‐by‐step approach through quantitative analyses and statistics
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