Search results for "GC"

Testing a portable laser-induced breakdown spectroscopy system on geological samples.

2012

9 pages; International audience; This paper illustrates the potentialities of a home-made portable LIBS (laser-induced breakdown spectroscopy) instrument in Earth sciences, more particularly in geochemically recognizing (i) tephra layers in lacustrine sediments and (ii) fossilization processes in ammonites. Abundances for selected lines of Al, Ca, Fe, Ti, Ba and Na were determined in lacustrine chalk sediments of the Jura, where the Laacher See Tephra (LST) layer is recorded. A statistical treatment of elemental maps produced from the section of a sedimentary column containing the LST event allows instrumental conditions to be optimized. Accumulating spectra from close shot positions gives …

Analysis of furan in toasted coffee by HS/SPME-GC-MS

2008

Occurrence of Fusarium mycotoxins and their dietary intake through beer consumption by the European population

2014

Abstract Since cereals are raw materials for production of beer and beer-based drinks, the occurrence mycotoxins in 154 beer samples was topic of investigation in this study. The analyses were conducted using QuEChERS extraction and gas chromatography–tandem mass spectrometry determination. The analytical method showed recoveries for vast majority of analytes ranged from 70% to 110%, relative standard deviations lower than 15% and limits of detection from 0.05 to 8 μg/L. A significant incidence of HT-2 toxin and deoxynivalenol (DON) were found in 9.1% and 59.7% of total samples, respectively. The exposure of European population to mycotoxins through beer consumption was assessed. No toxicol…

Differential essential oil composition and morphology between perennial satureja species growing in Spain

2015

Chemical composition of the essential oils obtained by hydrodistillation from the aerial parts of thirty six samples of perennial Spanish savouries (Satureja montana L., Satureja innota (Pau) G. López, Satureja cuneifolia Ten. and Satureja intricata Lange), was investigated by GC and GC-MS. A total of 72 compounds accounting between 98.25-99.55% of the total oil were identified. High content of carvacrol (59.72±1.50%) followed by g -terpinene (17.40±1.11%) were found in S.montana essential oils. S. cuneifolia yielded an oil rich in camphor (45.04±1.67%) and camphene (12.42±1.71%) whereas S. innota produces an essential oil with linalool (23.94±7.58%) or geraniol (8.62±3.45%) according to th…

GC-MS as a tool to study the aromatic profiles of Candida zemplinina/ Saccharomyces cerevisiae mixed fermentation wines

2013

STUDY OF VOLATILE COMPONENTS OF TEN VARIETIES OF SALVIA BY SPME-GC/MS AND GENERAL DISCRIMINANT ANALYSIS

2011

Tuning parameter selection in LASSO regression

2016

We propose a new method to select the tuning parameter in lasso regression. Unlike the previous proposals, the method is iterative and thus it is particularly efficient when multiple tuning parameters have to be selected. The method also applies to more general regression frameworks, such as generalized linear models with non-normal responses. Simulation studies show our proposal performs well, and most of times, better when compared with the traditional Bayesian Information Criterion and Cross validation.

Sch 9p kinase and the Gcn4p transcription factor regulate glycerol production during winemaking

2017

Grape juice fermentation is a harsh environment with many stressful conditions, and Saccharomyces cerevisiae adapts its metabolism in response to those environmental challenges. Many nutrient-sensing pathways control this feature. The Tor/Sch9p pathway promotes growth and protein synthesis when nutrients are plenty, while the transcription factor Gcn4p is required for the activation of amino acid biosynthetic pathways. We previously showed that Sch9p impact on longevity depends on the nitrogen/carbon ratio. When nitrogen is limiting, SCH9 deletion shortens chronological life span, which is the case under winemaking conditions. Its deletion also increases glycerol during fermentation, so the…

Joint Resource Allocation and UAV Scheduling With Ground Radio Station Sleeping

2021

Applications of Unmanned aerial vehicles (UAVs) have advanced rapidly in recent years. The UAVs are used for a variety of applications, including surveillance, disaster management, precision agriculture, weather forecasting, etc. In near future, the growing number of UAV applications would necessitate densification of UAV infrastructure (ground radio station (GRS) and ground control station (GCS)) at the expense of increased energy consumption for UAV communications. Maximizing the energy efficiency of this UAV infrastructure is important. Motivated by this, we propose joint resource allocation and UAV scheduling with GRS sleeping (GRSS). Further, we propose the use of coordinated multi-poi…

Comparative architectural aspects of regions of conserved synteny on human chromosome 11p15.3 and mouse chromosome 7 (including genes WEE1 and LMO1)

2001

Human chromosome 11p15.3 is associated with chromosome aberrations in the Beckwith Wiedemann Syndrome and implicated in the pathogenesis of different tumor types including lung cancer and leukemias. To date, only single tumor-relevant genes with linkage to this region (e.g. LMO1) have been found suggesting that this region may harbor additional potential disease associated genes. Although this genomic area has been studied for years, the exact order of genes/chromosome markers between D11S572 and the WEE1 gene locus remained unclear. Using the FISH technique and PAC clones of the flanking markers we determined the order of the genomic markers. Based on these clones we established a PAC cont…