Search results for "GC"
showing 10 items of 606 documents
I diritti audiovisivi sportivi in Italia prima e dopo il decreto Melandri Gentiloni
Metabolic signatures across the full spectrum of non-alcoholic fatty liver disease.
2022
Funder: European Commission
Comparison of 3 ionisation methods - electron ionisation, chemical ionisation and atmospheric pressure photoionisation - for the characterisation of …
2021
International audience; Gas chromatography (GC) is a reproducible, robust, selective and sensitive method to analyse volatile organic compounds (VOCs) in a wide range of applications. The separated analytes are generally characterised by mass spectrometry (MS) under vacuum conditions. The main ionisation method is the Electron Ionisation (EI): high energy exchanges occur, causing reproducible molecular fragmentations. Chemical Ionisation (CI) is another ionisation method where a reactive gas (i.e. methane or ammonia) is ionised to form reactant ions. GC-MS can also be conducted under atmospheric pressure. Atmospheric Pressure PhotoIonisation (APPI) is the most recent source [1]. Emitted pho…
UV variability and accretion dynamics in the young open cluster NGC 2264
2015
We explore UV and optical variability signatures for several hundred members of NGC 2264 (3 Myr). We performed simultaneous u- and r-band monitoring over two full weeks with CFHT/MegaCam. About 750 young stars are probed; 40% of them are accreting. Statistically distinct variability properties are observed for accreting and non-accreting cluster members. The accretors exhibit a significantly higher level of variability than the non-accretors, especially in the UV. The amount of u-band variability correlates statistically with UV excess in disk-bearing objects, which suggests that accretion and star-disk interaction are the main sources of variability. Cool magnetic spots, several hundred de…
Broadband X-ray spectral variability of the pulsing ULX NGC 1313 X-2
2021
[Context] It is thought that ultraluminous X-ray sources (ULXs) are mainly powered by super-Eddington accreting neutron stars or black holes as shown by the recent discovery of X-ray pulsations and relativistic winds. [Aims] This work presents a follow-up study of the spectral evolution over two decades of the pulsing ULX NGC 1313 X-2 in order to understand the structure of the accretion disc. The primary objective is to determine the shape and nature of the dominant spectral components by investigating their variability with the changes in the source luminosity. [Methods[ We performed a spectral analysis over the canonical 0.3-10.0 keV energy band of all the high signal-to-noise XMM-Newton…
Molecular basis of the effects of argan oil on mitochondrial and peroxisomal metabolism of the fatty acids and inflammation
2012
The objective of this thesis work was to explore the molecular basis of Argan Oil (AO) effects on the mitochondrial and peroxisomal lipid metabolism and to elucidate its anti-inflammatory potential. We thus showed, initially, that the artisanal method preparation preserved the antioxidant properties of AO preventing the oxidation of the ferulic acid, by contrast to AO of commercial origin. Then, the treatment by the AO or lipopolysaccharides (LPS) of human fibroblasts, the cellular model of pseudo-neonatal adrenoleukodystrophy (P-NALD), revealed for the AO that peroxisomes proliferation is independent from the activation of the nuclear receptor PPARα and the co-activator PGC-1α. On the othe…
Acute Myocardial Infarction and Proinflammatory Gene Variants
2007
We identified four genetic risk sets for acute myocardial infarction (AMI) from information on functional gene variants that favor inflammation or modulate cholesterol metabolism: IL6 -174 G/C, TNF -308 G/A, IL10 -1082 G/A, SERPINA3 -51 G/T, IFNG +874 T/A, HMGCR -911 C/A, and APOE ε2/3/4; 316 patients and 461 healthy subjects, all Italian. Putative risk alleles are shown underlined. The sets were identified using grade-of-membership analysis. Membership scores in the sets are automatically generated for individuals. The ''low intrinsic risk'' set had alleles that downregulate inflammation and cholesterol synthesis (IL6, TNF, ILl0, HMGCR). ''AMI across a broad age range'' carried multiple pr…
Detection of gamma-hydroxybutyrate in hair: Validation of GC–MS and LC–MS/MS methods and application to a real case
2012
A gas chromatography-mass spectrometry (GC-MS) and a liquid chromatography tandem mass spectrometry (LC-MS/MS) method were validated for quantifying endogenous and exogenous hair concentrations of gamma-hydroxybutyrate (GHB). The GC-MS method is based on overnight extraction of 25 mg hair in NaOH at 56 °C, liquid/liquid extraction in ethylacetate and trimethylsylil derivatization; analysis is by electron ionization and single ion monitoring of three ions. The LC-MS/MS method entails a rapid digestion of 25 mg hair with NaOH at 75 °C for 40 min, liquid/liquid extraction in ethylacetate and reconstitution of the extract in the LC mobile phase; negative ion electrospray ionization and multiple…
Understanding the role of saliva in aroma release from wine by using static and dynamic headspace conditions.
2014
The aim of this work was to determine the role of saliva in wine aroma release by using static and dynamic headspace conditions. In the latter conditions, two different sampling points (t = 0 and t = 10 min) corresponding with oral (25.5 °C) and postoral phases (36 °C) were monitored. Both methodologies were applied to reconstituted dearomatized white and red wines with different nonvolatile wine matrix compositions and a synthetic wine (without matrix effect). All of the wines had the same ethanol concentration and were spiked with a mixture of 45 aroma compounds covering a wide range of physicochemical characteristics at typical wine concentrations. Two types of saliva (human and artifici…
Biomonitoring of Multiple Mycotoxins in Urine by GC–MS/MS: A Pilot Study on Patients with Esophageal Cancer in Golestan Province, Northeastern Iran
2021
A pilot study to investigate the occurrence of 10 mycotoxins (deoxynivalenol, DON