Search results for "GC"
showing 10 items of 606 documents
Volatile compounds of fresh fruits of Phillyrea latifolia L.
2004
The volatiles constituents of fresh fruits of Phillyrea latifolia were submitted to investigation by GC-MS. The plants grows wild in different zones of the mediterranean region and its leaves and fruits are used as astringent, diuretic and anti-inflammatory. The volatiles were sampled by solid-phase microextraction (SPME), with a 100 mm polydimethylsiloxane fibre a 50 °C for 1 h. The headspace main components of fresh fruits of Phillyrea latifolia included limonene, β-cariophillene, eremophilene, α-muurolene, β -eudesmol e spatulenol.
Water-use efficiency and transpiration across European forests during the Anthropocene
2015
Considering the combined effects of CO2 fertilization and climate change drivers on plant physiology leads to a modest increase in simulated European forest transpiration in spite of the effects of CO2-induced stomatal closure. The Earth’s carbon and hydrologic cycles are intimately coupled by gas exchange through plant stomata1,2,3. However, uncertainties in the magnitude4,5,6 and consequences7,8 of the physiological responses9,10 of plants to elevated CO2 in natural environments hinders modelling of terrestrial water cycling and carbon storage11. Here we use annually resolved long-term δ13C tree-ring measurements across a European forest network to reconstruct the physiologically driven r…
23 GHz VLBI observations of SN 2008ax (Research Note)
2009
We report on phase-referenced 23 GHz Very-Long-Baseline-Interferometry (VLBI) observations of the type IIb supernova SN 2008ax, made with the Very Long Baseline Array (VLBA) on 2 April 2008 (33 days after explosion). These observations resulted in a marginal detection of the supernova. The total flux density recovered from our VLBI image is 0.8 ± 0.3 mJy (one standard deviation). As it appears, the structure may be interpreted as either a core-jet or a double source. However, the supernova structure could be somewhat confused with a possible close by noise peak. In such a case, the recovered flux density would decrease to 0.48 ± 0.12 mJy, compatible with the flux densities measured with the…
Implementation of rapid method for the isolation of 2-dodecylcylobutanone from irradiated meat and dose estimation based on GC/MS
2008
Chemical Composition of the Essential Oil of Teucrium flavum ssp. flavum from Zakynthos, Greece
2012
Essential oil extracted from dried aerial parts of Teucrium flavum ssp. flavum harvested in Zakynthos, Greece, was analysed by gas phase chomatography (GC) and gas chomatography mass spectrometry (GC-MS). The main constituents were caryophyllene (13.5%), caryophyllene oxide (8.5%), 4-vinyl guaiacol (6.0%) and α- humulene (5.0%).
The Influence of Chemical Composition of Commercial Lemon Essential Oils on the Growth of Candida Strains
2013
Candida yeasts are saprophytes naturally present in the environment and forming colonies on human mucous membranes and skin. They are opportunistic fungi that cause severe and even fatal infections in immunocompromised individuals. Several essential oils, including eucalyptus, pine, cinnamon and lemon, have been shown to be effective against Candida strains. This study addresses the chemical composition of some commercial lemon essential oils and their antifungal potential against selected Candida yeast strains. Antifungal potential and minimum inhibitory concentrations were determined for six commercial lemon essential oils against five Candida yeast strains (Candida albicans 31, Candida t…
Pairwise and higher-order measures of brain-heart interactions in children with temporal lobe epilepsy
2022
Abstract Objective. While it is well-known that epilepsy has a clear impact on the activity of both the central nervous system (CNS) and the autonomic nervous system (ANS), its role on the complex interplay between CNS and ANS has not been fully elucidated yet. In this work, pairwise and higher-order predictability measures based on the concepts of Granger Causality (GC) and partial information decomposition (PID) were applied on time series of electroencephalographic (EEG) brain wave amplitude and heart rate variability (HRV) in order to investigate directed brain-heart interactions associated with the occurrence of focal epilepsy. Approach. HRV and the envelopes of δ and α EEG activity re…
Curcumin and Andrographolide Co-Administration Safely Prevent Steatosis Induction and ROS Production in HepG2 Cell Line
2023
Non-alcoholic fatty liver disease (NAFLD) is an emerging chronic liver disease worldwide. Curcumin and andrographolide are famous for improving hepatic functions, being able to reverse oxidative stress and release pro-inflammatory cytokines, and they are implicated in hepatic stellate cell activation and in liver fibrosis development. Thus, we tested curcumin and andrographolide separately and in combination to determine their effect on triglyceride accumulation and ROS production, identifying the differential expression of genes involved in fatty liver and oxidative stress development. In vitro steatosis was induced in HepG2 cells and the protective effect of curcumin, andrographolide, and…
Sedimentation and tropical vegetation changes in Southern Benin (West Africa), carbon-13 tracing of organic matter dynamics and fluctuations of the s…
2007
12 pages; International audience
Mass spectrometry coupled to chromatography systems and cultural heritage: a case study on the content of an ancient jar
2009
In this chapter an introduction to mass spectrometry will be given, with particular reference to mass spectrometry coupled to chromatography systems. Further some mass spectrometry applications in the field of cultural heritage will be briefly reported and discussed. Finally a experimental investigation on the content of an ancient jar will be reported. Together with experimental details a description of the techniques adopted, results obtained and forthcoming experiments will be also given.