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71.
Daniela Metro Roberta Tardugno Mattia Papa Carlo Bisignano Luigi Manasseri Giorgio Calabrese 《Natural product research》2018,32(15):1775-1781
Since the last decades, socio-economic changes have a key role on eating habits affecting the nutritional status and health of people, in particular children and adolescents. The aim of this study was to compare the diet of student population both normal weight and overweight and obese in order to understand their eating habits by comparing the different diets of the student referring to the Mediterranean diet. The study comprised 337 Sicilian students aged 9 to 13 years, 96 in primary schools and 241 in secondary schools, respectively, in three Sicilian cities namely, Messina, San Piero Patti and Ragusa. The variables studied were height, weight, body mass index (BMI) and adherence to the Mediterranean Adequacy Index (MAI) diet quality indicator. Interestingly, the results highlighted 2.67 MAI mean value for normal weight students while 1.27 MAI mean value indicating a decreased adherence to the Mediterranean diet in overweight students. 相似文献
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Kava (Piper methysticum) dietary products have been sold worldwide for treatment of nervous anxiety, tension, and restlessness. Recent reports showed potential association of kava usage and liver injuries. This study was conducted to develop simple and reliable methodologies for the extraction and determination of 6 major kavalactones: (+)-methysticin, (+)-dihydromethysticin, (+)-kavain, (+)-dihydrokavain, yangonin, and desmethoxyyangonin. Ultrasonic extraction techniques and isocratic reversed-phase liquid chromatography (LC) were optimized for different types of samples, including capsules containing kava root extract or root powder, raw root material, tea bags, and snack bar. A suitable internal standard, 5,7-dihydroxyflavone, was used for LC calibration. Kavalactones were completely separated in 30 min using a Luna C18-2 column at 60 degrees C with an isocratic mobile phase consisting of 2-propanol-acetonitrile-water-acetic acid (16 + 16 + 68 + 0.1, v/v/v/v). Within-laboratory, intraday, and interday method variation (% relative standard deviation) for most samples extracted by methanol or methanol-water mixture were <5%. Lower levels of kavalactone contents and higher variations were observed for tea bags from water extraction or infusion as compared to methanol extraction. Labeling information of tea bags based on methanol extraction could be misleading to consumers. Analytical recoveries of snack bar fortified at 10 and 20 microg/g were >84% with RSD values <8%. Methods developed in this study offer a simple and reproducible means for analysis of kavalactones in various matrixes of dietary products. 相似文献
76.
Giuseppe A. Consiglio Salvatore Failla Paolo Finocchiaro Kenneth I. Hardcastle 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):697-700
Williamson condensation of bis-o-hydroxy aryl phosphonates with dihaloalkylaryl derivatives yields the title compounds. They show interesting stereochemical aspects and some of them can be used in chiral recognitions and separations. 相似文献
77.
Dr. Cristina Parisi Dr. Mariacristina Failla Dr. Aurore Fraix Dr. Barbara Rolando Dr. Eleonora Gianquinto Prof. Francesca Spyrakis Dr. Elena Gazzano Prof. Chiara Riganti Prof. Loretta Lazzarato Prof. Roberta Fruttero Prof. Alberto Gasco Prof. Salvatore Sortino 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(47):11080-11084
Two novel NO photodonors (NOPDs) based on BODIPY and Rhodamine antennae activatable with the highly biocompatible green light are reported. Both NOPDs exhibit considerable fluorescence emission and release NO with remarkable quantum efficiencies. The combination of the photoreleasing and emissive performance for both compounds is superior to those exhibited by other NOPDs based on similar light-harvesting centres, making them very intriguing for image-guided phototherapeutic applications. Preliminary biological data prove their easy visualization in cell environment due to the intense green and orange-red fluorescence and their photodynamic action on cancer cells due to the NO photo-liberated. 相似文献
78.
Metric inequalities and the Network Loading Problem 总被引:1,自引:0,他引:1
Given a simple graph G(V,E) and a set of traffic demands between the nodes of G, the Network Loading Problem consists of installing minimum cost integer capacities on the edges of G allowing routing of traffic demands.In this paper we study the Capacity Formulation of the Network Loading Problem, introducing the new class of Tight Metric Inequalities, that completely characterize the convex hull of the integer feasible solutions of the problem.We present separation algorithms for Tight Metric Inequalities and a cutting plane algorithm, reporting on computational experience. 相似文献
79.
Mathematical Notes - In this paper, we compute the degree of the Kodiyalam polynomials of an ideal in the case where its Rees ring is Cohen—Macaulay and its fiber ring is a domain. We apply... 相似文献
80.
Verónica M. Riechert Aníbal G. Ferrofino Jorge A. Ressia Marcelo D. Failla 《International Journal of Polymer Analysis and Characterization》2019,24(4):355-373
Five commercial random propylene-α-olefin copolymers were functionalized with maleic anhydride by reactive mixing. Materials and blends of the original polymers with the grafted ones were characterized by IR, SEC, rheology, XRD, and DSC. The effects of ethylene content and average molecular weights on the effectiveness of scission and grafting reactions were investigated. Functionalization gives place to thermo-rheologically simple materials whose dynamic properties are in agreement with the measured molecular weights. The blends, which stand as miscible ones, display terminal dynamic moduli and crystallization and melting temperatures that show slight positive deviation with respect to linear mixing rules. 相似文献