Search results for " TRACE"

Utilizzo di traccianti geochimici nella Limonicoltura Siciliana.

2018

Nell’ultimo decennio i consumatori hanno sviluppato un interesse crescente per la tracciabilità dei prodotti agroalimentari in particolare in relazione all’origine geografica. La conoscenza di una possibile relazione chimica tra suolo e prodotti agroalimentari è importante per valutare la provenienza e autenticità dei prodotti. Tutto ciò va a favore del consumatore e si traduce in maggiore sicurezza e qualità dell’alimento. La coltivazione del Limone (Citrus Limon (L.) Osbeck) è una delle più importanti colture al mondo e l'individuazione di potenziali frodi potrebbe essere migliorata studiando la sua composizione chimica che lo lega all’area di origine. Questo studio ha utilizzato le terre…

Analysis of the OSU-MASLWR Natural circulation phenomena using TRACE code

2009

The HOMFLY-PT polynomials of sublinks and the Yokonuma–Hecke algebras

2016

We describe completely the link invariants constructed using Markov traces on the Yokonuma-Hecke algebras in terms of the linking matrix and the HOMFLYPT polynomials of sublinks.

Coverage intervals for trace elements in human scalp hair are site specific.

2014

Coverage intervals for trace elements in human scalp hair commonly provide the basis for interpreting laboratory results and also in comparative decision-making processes regarding exposure risk assessment. This short communication documents, by some examples, that those computed for human hair are to be considered site specific, as they reflect local environmental conditions; also each geographic area has a typical profile of hair elemental composition of its inhabitants. Therefore, the levels of trace elements in hair are not strictly comparable between different areas of the world. This issue is particularly relevant when identification of anomalous environmental exposures are requested …

Synthesis and evaluation in rats of the dopamine D2/3 receptor agonist 18F-AMC20 as a potential radioligand for PET

2015

Dopamine D2/3 receptor (D2/3R) agonist PET tracers are better suited for the imaging of synaptic dopaminergic neurotransmission than D2/3R antagonists and may also offer the opportunity to study in vivo the high-affinity state of D2/3R (D2/3RHigh). With the aim to develop 18F-labeled D2/3R agonists suitable for widespread clinical application, we report here on the synthesis and in vitro and in vivo evaluation of a D2/3R agonist ligand from the aminomethyl chromane (AMC) class-(R)-2-[(4- 18Fluorobenzylamino)methyl]chroman-7-ol (18F-AMC20). Methods: In vitro affinities of AMC20 toward dopaminergic receptor subtypes were measured in membrane homogenates prepared from HEK293 cells expressing h…

18F-labeling and evaluation of novel MDL 100907 derivatives as potential 5-HT2A antagonists for molecular imaging.

2009

Abstract Introduction The serotonergic system, especially the 5-HT2A receptor, is involved in various diseases and conditions. It is a very interesting target for medicinal applications. Methods Two novel 5-HT2A tracers, namely, [ 18 F]DD-1 and the enantiomeric pure ( R )-[ 18 F]MH.MZ, were radiolabeled by 18 F-fluoroalkylation of the corresponding desmethyl analogue. In vitro binding autoradiography on rat brain slices was performed to test the affinity and selectivity of these tracers. Moreover, first μPET experiments of ( R )-[ 18 F]MH.MZ were carried out in Sprague-Dawley rats. Results [ 18 F]DD-1 ( K i =3.23 nM) and ( R )-[ 18 F]MH.MZ ( K i =0.72 nM) were 18 F-fluoroalkylated by the se…

Levels of trace elements in human hair samples of adolescents living near petrochemical plants

2020

The aim of the study is a comparative analysis to investigate human hair metal profiles of adolescents residing near petrochemical plants (Sicily, Italy). We selected the small town of Augusta, Gela, and Pace del Mela, and a control area made up of the towns characterized by low anthropogenic activity. Twenty trace elements were measured in samples of scalp hair from adolescents (11–14 years old) of both genders. Hair samples were cleaned using a rigorous cleaning method, mineralized, and processed for analyses by inductively coupled plasma–mass spectrometry (ICP-MS). In industrial sites, zinc was always the most abundant element, ranging from186 to 217 μg g−1. Following zinc, the elements …

Preliminary study on trace metal content in manna extracted from Fraxinus angustifolia cultivars in Madonie (Sicily, Italy)

2019

The manna is a product obtained from the elaborate sap solidification that comes out from the incisions made on the stem of some species of the genus Fraxinus L. In this study, we have analyzed 12 samples of manna to determine the chemical composition. Twenty elements (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Rb, Sb, Se, Sr, U, V, Zn) were determined using an Inductively Coupled Plasma Mass Spectrometer. The results show that the most abundant elements are Fe > Rb > Al > Cu > Ba > Zn > Sr with median concentrations in the range of 0.9 – 10mg kg-1. The remaining elements exhibit median concentrations in the range of 0.0003 -0.5 mg kg-1. The manna also can be cons…

Mass spectrometry analysis of volatile compounds in raw meat for the authentication of the feeding background of farm animals.

2007

The authentication of the conditions of animal production, based on the analysis of meat commercial cuts, is a major challenge on both societal and analytical grounds. The aim of the present work was to propose a method for the extraction of the volatile compounds from ruminant raw muscles trimmed of fat and to assess by mass spectrometry-based techniques the relevance of these compounds for the authentication of the type of feeding offered to the animals. The first step of the study consisted of validating conditions of dynamic headspace (DH) extraction of volatile compounds that enabled us to minimize the appearance of heat-induced artifacts and to maximize the richness of the DH-gas chro…

Chronological records of metal deposition in sediments from the Strait of Sicily, central Mediterranean: assessing natural fluxes and anthropogenic a…

2010

Abstract Sediment box-cores were recovered from the Strait of Sicily along two onshore–offshore transects in water depths of 29–500 m. Samples were dated by 210 Pb and analysed for major and trace elements. Inspections of chronological profiles integrated with application of statistical algorithms to the geochemical dataset and supported by in situ hydrological observations were used to assess factors driving element distributions. Mineralogical and chemical variability of sediments offshore of the southwestern Sicily coast reflect the irregular sea floor morphology of the Adventure Bank. Anthropogenic inputs explain enrichments with respect to background values for Sb, As, Pb, and Hg, that…