Search results for "Extraction"

Preliminary Estimation of Deoxynivalenol Excretion through a 24 h Pilot Study

2015

A duplicate diet study was designed to explore the occurrence of 15 Fusarium mycotoxins in the 24 h-diet consumed by one volunteer as well as the levels of mycotoxins in his 24 h-collected urine. The employed methodology involved solvent extraction at high ionic strength followed by dispersive solid phase extraction and gas chromatography determination coupled to mass spectrometry in tandem. Satisfactory results in method performance were achieved. The method"s accuracy was in a range of 68%108%, with intra-day relative standard deviation and inter-day relative standard deviation lower than 12% and 15%, respectively. The limits of quantitation ranged from 0.1 to 8 μg/Kg. The matrix effect w…

Infant exposure of perfluorinated compounds: Levels in breast milk and commercial baby food

2010

In this study, an analytical method to determine six previous termperfluorinatednext term compounds (PFCs) based on alkaline digestion and solid phase extraction (SPE) followed by liquid chromatography-quadrupole-linear ion trap mass spectrometry (LC-QqLIT-MS) was validated for the analysis of human breast milk, milk previous terminfantnext term formulas and cereals baby food. The average recoveries of the different matrices were in general higher than 70% with a relative standard deviation (RSD) lower than 21% and method limits of detection (MLOD) ranging from 1.2 to 362 ng/L for the different compounds and matrices. The method was applied to investigate the occurrence of PFCs in 20 sample…

Dentifrices : an update

2010

Objectives; The objective of this paper was to review the published evidence concerning the efficacy and potential for adverse reactions of modern dentifrices toothpastes. Data sources; Publications cited on MEDLINE since 1990. Some further pre-1990 publications are also referenced. Data selection; Studies concerning the efficacy of dentifrices and their components and any related putative adverse incidents. Data extraction; Papers were scrutinised for scientific and trial data. Data synthesis; Data concerning the efficacy of dentifrice components were summarised. Conclusions; The efficacy of fluoride salts in dentifrices in reducing dental caries is well established. Toothpastes, containin…

A comparison of extraction procedures for water-extractable organic matter in soils

2014

The characteristics of dissolved organic matter (DOM) in soils are often determined through laboratory experiments. Many different protocols can be used to extract organic matter from soil. In this study, we used five air-dried soils to compare three extraction methods for water-extractable organic matter (WEOM) as follows: (i) pressurised hot-water-extractable organic carbon (PH-WEOC), a percolation at high pressure and temperature; (ii) water-extractable organic carbon (WEOC), a 1-hour end-over shaking; and (iii) leaching-extractable organic carbon (LEOC), a leaching of soil columns at ambient conditions. We quantified the extraction yield of organic carbon; the quality of WEOM was charac…

Surveillance of pesticide residues in fruits from Valencia during twenty months (2004/05)

2010

Abstract The aim of this study was to investigate the pesticide residues in market fruits (oranges, tangerines, nectarines, peaches and khakis) from one Valencian Cooperative (Spain) and to conduct a monitoring of 32 organophosphorous, organonitrogen and organohalogenated pesticides and nine dithiocarbamate fungicides (DTCFs) usually applied on cultures of this area. Extracts were obtained by an official procedure for routine analysis based on ethyl acetate extraction. Residues of pesticides were determined by gas chromatography with nitrogen phosphorous detector (NPD), electron-capture detector (ECD) and mass spectrometry (MS) detectors. Mean recoveries obtained at fortification levels bet…

Extraction and trace enrichment of genotoxicants from environmental samples by solid-phase adsorption on blue pearls

1988

Tomographic image processing for the morphological and metrological study of Valsalva sinuses

2012

This Phd thesis deals with the design and the use of image processing tools in order to allow a reliable and objective study of the sinuses of Valsalva which are important cavities of the aortic root. The proposed methods can be applied on cine-MR sequences and CT examinations without any change in the settings between two examinations.Firstly, we studied the morphology of this anatomical area and its constant properties in all images of the dataset. Sinuses are one of the main bright organs with limited movements. Hence a new algorithm has been designed. It detects and characterizes each bright organ by a single trajectory. Various tools of mathematical morphology are used for this step, a…

Utilisation of natural carotenoids from Momordica cochinchinensis (gac) as health compounds : extraction and bioactvity depending on the origin and o…

2014

The aril of Momordica cochinchinensis (gac), plant from the Cucurbitaceae family, is the richest source of lycopene and β-carotene, which are a strong antioxidant and a pro-vitamin A, respectively, interesting for health-complements. First, a process of soft extraction-fractionation was developed for extracting effectively the natural carotenoids from gac without loss of their original quality. Then, the lycopene and β-carotene extracted from gac were analyzed and characterized. At least 95% of the extracts were composed of the all-trans isomer. They were not degraded during the heat-treatment mimicking formulation processing. Their thermal stereo-mutation was evaluated. Lycopene is more an…

Texture analysis with statistical methods for wheat ear extraction

2007

In agronomic domain, the simplification of crop counting, necessary for yield prediction and agronomic studies, is an important project for technical institutes such as Arvalis. Although the main objective of our global project is to conceive a mobile robot for natural image acquisition directly in a field, Arvalis has proposed us first to detect by image processing the number of wheat ears in images before to count them, which will allow to obtain the first component of the yield. In this paper we compare different texture image segmentation techniques based on feature extraction by first and higher order statistical methods which have been applied on our images. The extracted features are…

Automatic Extraction of Semantic Roles in Support Verb Constructions

2021

This paper deals with paraphrastic relations in Italian. In the following sentences: (a) Max strappò delle lacrime a Sara 'Max moved Sara to tears' and (b) Max fece piangere Sara 'Max made Sara cry', the verbs differ syntactically and semantically. Strappare 'tear/rip/wring' is transitive, fare ‘have/make’ is a causative, and piangere 'cry' is intransitive. Despite this, a translation of (a) as (b) is legitimate and therefore (a) is a paraphrase of (b). In theoretical linguistics this raises an issue concerning the relationship between strappare and fare/piangere in Italian, and that in English between move and make. In computational linguistics, can such paraphrases be obtained automatical…