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711.
Torelli E Firrao G Bianchi G Saccardo F Locci R 《Journal of the science of food and agriculture》2012,92(8):1808-1814
BACKGROUND: Contamination by mycotoxins is a major concern to the maize industry in north‐east Italy where maize grain is often spoiled by Fusarium spp. In this work, fumonisins, deoxynivalenol and zearalenone were determined and an artificial neural network (ANN) model suitable for predicting mycotoxin contamination of maize at harvest time was developed. RESULTS: The occurrence of deoxynivalenol and zearalenone was very limited, while fumonisins concentration ranged from 163 and to 3663 µg kg?1 in 2007, and from 333 to 11473 µg kg?1 in 2008. Statistical data analysis of factors affecting fumonisins concentration revealed that irrigation, chemical treatment against the European corn borer and harvest date significantly affected the level of contamination (P < 0.05), although the relevance of the factors was different in 2007 and 2008. The neural network approach showed a significant correlation between ascertained values and predictions based on agronomic data. CONCLUSION: This is the first time that an artificial neural network has been used to predict fumonisin accumulation in maize: the prediction has been shown to have the potential for the development of a new approach for the rapid cataloging of grain lots. Copyright © 2012 Society of Chemical Industry 相似文献
712.
De Sanctis F Silvestrini MG Luneia R Botondi R Bellincontro A Mencarelli F 《Food chemistry》2012,135(3):1619-1625
Wine white grape bunches of the Grechetto variety were dehydrated at 10, 20 and 30°C, RH 45% and forced air ventilation of 1.5m/s. Chemical and metabolic changes due to the effect of dehydration were studied at various stages of weight loss: 10%, 20%, 30% and 40%. Berry colour at 10 and 20°C tended to become greener with dehydration but at 30°C, at the final sampling, the colour darkened. Acidity decreased in all samples, while sugars increased. Total phenol content increased at 10°C until 30% weight loss was reached and then declined, while at 20 and 30°C the concentration decreased immediately. The contents of lutein and β-carotene (respectively 68 and 58mg/kg d.w.), representing the 80% of total carotenoids, did not change significantly until the 30% of weight loss, when at 30°C the value increased above all for lutein while at 10 and 20°C, the contents decreased significantly. Daidzein, at 10°C, rose significantly from about 150μg/kg d.w. to 1434μg/kg d.w. at 20% weight loss and then declined; at the same weight loss percentage, the genistein concentration began to increase. At 20°C both isoflavones rose until the end of the experiment, reaching values similar to the sample at 10°C. A temperature of 30°C was deleterious to grape isoflavones. A discussion on the changes in isoflavones related to temperature and time is reported. 相似文献
713.
Elisabetta Coppi Federica Cherchi Elena Lucarini Carla Ghelardini Felicita Pedata Kenneth A. Jacobson Lorenzo Di Cesare Mannelli Anna Maria Pugliese Daniela Salvemini 《International journal of molecular sciences》2021,22(15)
Agonists of the Gi protein-coupled A3 adenosine receptor (A3AR) have shown important pain-relieving properties in preclinical settings of several pain models. Active as a monotherapy against chronic pain, A3AR agonists can also be used in combination with classic opioid analgesics. Their safe pharmacological profile, as shown by clinical trials for other pathologies, i.e., rheumatoid arthritis, psoriasis and fatty liver diseases, confers a realistic translational potential, thus encouraging research studies on the molecular mechanisms underpinning their antinociceptive actions. A number of pathways, involving central and peripheral mechanisms, have been proposed. Recent evidence showed that the prototypical A3AR agonist Cl-IB-MECA and the new, highly selective, A3AR agonist MRS5980 inhibit neuronal (N-type) voltage-dependent Ca2+ currents in dorsal root ganglia, a known pain-related mechanism. Other proposed pathways involve reduced cytokine production, immune cell-mediated responses, as well as reduced microglia and astrocyte activation in the spinal cord. The aim of this review is to summarize up-to-date information on A3AR in the context of pain, including cellular and molecular mechanisms underlying this effect. Based on their safety profile shown in clinical trials for other pathologies, A3AR agonists are proposed as novel, promising non-narcotic agents for pain control. 相似文献
714.
715.
Carlos Mota Dario Puppi Matteo Gazzarri Paulo Bártolo Federica Chiellini 《Polymer International》2013,62(6):893-900
In the last decade, the melt‐electrospinning technique has gained attention for the production of highly porous microfibrous tissue engineering scaffolds. The possibility of processing polymers without the use of organic solvents is one of the main advantages over solution electrospinning. In this study, computer‐controlled melt‐electrospinning of a commercial poly(?‐caprolactone) and of two batches with different molecular weights of a three‐arm star poly(?‐caprolactone) by means of a screw‐extruder‐based additive manufacturing system is reported. Experimental parameters such as processing temperature, extrusion flow rate and applied voltage were studied and optimized in order to obtain non‐woven meshes with uniform fibre morphology. Applying the optimized parameters, three‐dimensional scaffolds were produced using a layer‐by‐layer approach (0 ? 90° lay‐down pattern). © 2013 Society of Chemical Industry 相似文献
716.
Camilla Lazzi Federica Meli Francesca Lambertini Chiara Bottesini Ilya Nikolaev Monica Gatti Stefano Sforza Olga Koroleva Vladimir Popov Erasmo Neviani Arnaldo Dossena 《International Journal of Food Science & Technology》2013,48(2):341-349
Bacterial growth media represent a high cost in industrial applications, and for this reason, it is economically important to find less expensive supplements to replace the traditional ones. In the present work, peptide hydrolysates obtained from poultry meat and bone residues (functional animal protein [FAP]) and from feathers (functional feather protein [FFP]) were studied to determine their ability for the production of microbial biomass with improved viability. The results obtained were compared with those obtained with other supplement nutritive compounds used in fermentation growth media. The molecular composition of the hydrolysates in terms of total and soluble nitrogen, molecular weight distribution, total and free amino acids, was determined. The growth and cellular state of Bifidobacterium and Lactobacillus strains were studied by turbidimetric measurements and direct count by fluorescence microscopy. Overall, this study suggested that by‐products from poultry industry provide a good alternative to substitute expensive supplements for growth of Lactobacillus and Bifidobacterium with a high level of viability. 相似文献
717.
718.
Distance measures and geometrical features are widely used to describe faces. Generally, they are extracted punctually from landmarks, namely anthropometric reference points. The aims are various, such as face recognition, facial expression recognition, face detection, study of changes in facial morphology due to growth, or dysmorphologies. Most of the time, landmarks were extracted with the help of an algorithm or manually located on the faces. Then, measures are computed or geometrical features are extracted to perform the scope of the study. This paper is intended as a survey collecting and explaining all these features, in order to provide a structured user database of the potential parameters and their characteristics. Firstly, facial soft-tissue landmarks are defined and contextualized; then the various measures are introduced and some results are given; lastly, the most important measures are compared to identify the best one for face recognition applications. 相似文献
719.
Nicoletta Ravasio Federica Zaccheria Matteo Guidotti Rinaldo Psaro 《Topics in Catalysis》2004,27(1-4):157-168
Selective reactions of terpenes, catalyzed by different heterogeneous systems, are reported. α-pinene and limonene epoxides can be effectively isomerized to carbonyl compounds (selectivity >70%) over silica aluminas that appear to be good alternatives to homogeneous ZnBr2. The different reactivity of geometric isomers can be used to separate them. Unsaturated ketones can be converted through a two-step one-pot reaction in cyclic or bicyclic ethers through a bifunctional process involving a hydrogenation and an acid-catalyzed step. However, the choice of the solvent allows to inhibit the acidic sites, thus obtaining a selective hydrogenation reaction. On the other hand, the acidic reaction alone can be useful for alcohol epimerization and epimer separation. Grafting of Ti in a siliceous matrix gives rise to a material with both redox and acidic properties. Solids obtained in this way are active and selective in the epoxidation of terpenic alcohols but can also promote bifunctional reactions. 相似文献
720.
Pradip Paudyal Federica Battisti Marco Carli 《Multimedia Tools and Applications》2016,75(23):16461-16485
The analysis of the impact of video content and transmission impairments on Quality of Experience (QoE) is a relevant topic for the robust design and adaptation of multimedia infrastructures, services, and applications. The goal of this paper is to study the impact of video content on QoE for different levels of impairments. In more details, this contribution aims at i) the study of the impact of delay, jitter, packet loss, and bandwidth on QoE, ii) the analysis of the impact of video content on QoE, and iii) the evaluation of the relationship between content related parameters (spatial-temporal perceptual information, motion, and data rate) and the QoE for different levels of impairments. 相似文献