Search results for "monitor"
showing 10 items of 3841 documents
Impact of trace metals from past mining on the aquatic ecosystem: a multi-proxy approach in the Morvan (France).
2014
10 pages; International audience; This study seeks to determine to what extent trace metals resulting from past mining activities are transferred to the aquatic ecosystem, and whether such trace metals still exert deleterious effects on biota. Concentrations of Cd, Cu, Pb and Zn were measured in streambed sediments, transplanted bryophytes and wild brown trout. This study was conducted at two scales: (i) the entire Morvan Regional Nature Park and (ii) three small watersheds selected for their degree of contamination, based on the presence or absence of past mining sites. The overall quality of streambed sediments was assessed using Sediment Quality Indices (SQIs). According to these standar…
Application of dual boundary element method in active sensing
2013
In this paper, a boundary element method (BEM) for the dynamic analysis of 3D solid structures with bonded piezoelectric transducers is presented. The host structure is modelled with BEM and the piezoelectric transducers are formulated using a 3D semi-analytical finite element approach. The elastodynamic analysis of the entire structure is carried out in Laplace domain and the response in time domain is obtained by inverse Laplace transform. The BEM is validated against established finite element method (FEM).
Classification of European bog vegetation of the Oxycocco-Sphagnetea class
2022
Aims: Classification of European bog vegetation (Oxycocco-Sphagnetea class); identification of diagnostic species for the class and vegetation subgroups (orders and alliances); development of an expert system for automatic classification of vegetation plots; and production of distribution maps of the Oxycocco-Sphagnetea class and its alliances. Location: Europe. Methods: A data set of vegetation-plot records was compiled to include various bog types over most of the European continent. An unsupervised classification (beta-flexible linkage method, Sørensen distance measure) and detrended correspondence analysis (DCA) ordination were applied. Formal definitions of syntaxa based on species pre…
Perfluoroalkyl substances in Breast milk, infant formula and baby food from Valencian Community (Spain)
2016
Environmental and human exposures to perfluoroalkyl substances (PFASs) are of emerging concern since they are persistent and bioaccumulative. The present study reports PFASs levels in human milk, infant formulas and baby food (dry cereals and pots) from the Valencian Community (Spain) in order to evaluate the infant exposure to these substances through the diet. The results show that perfluorobutanoic acid (PFBA) and perfluorooctanoic acid (PFOA) were in all the samples of the four selected matrices (except PFOA in one sample of dry cereal baby food). Perfluoroheptanoic acid (PFHpA) and perfluorodecanoic acid (PFDA) were also detected in 70% of the breast milk samples. In infant formulas, P…
Polydimethylsiloxane (silicone rubber) brooch as a personal passive air sampler for semi-volatile organic compounds
2018
Exposure assessments conducted using a personal sampler include the contribution of human activities to exposure that is neglected when using a stationary air sampler. This study evaluated the uptake characteristics and application of the polydimethylsiloxane (PDMS or silicone rubber) brooch as a personal passive air sampler (PPAS) for measuring concentrations of two groups of semi-volatile organic compounds (SVOCs), namely phthalates and organophosphate esters (OPEs), indoors in proximity to the breathing zone. Uptake rates of the PDMS brooch were calibrated against a personal low volume active air sampler (PLV-AAS) co-deployed on each of five study participants working in offices for 8 hs…
Uses of weeds as an economical alternative to processed wood biomass and fossil fuels
2016
Abstract The use of fossil fuels as a main source of energy is directly linked to global climate change (due to CO2 emission), so there is a necessity to find new, cheap and easily available energy sources for the earth’s inhabitants. Nowadays renewable energy sources are forced also for the mitigation of the effects of climate change as a result of greenhouse gases emission control. Decentralized sources of low-cost renewable fuels that may be used, in particular, in those households where there is no possibility of using gas or heat delivered from other sources should be of special interest. This paper describes the possibility of using untreated plants such as Canadian goldenrod (Solidag…
A denuder-impinger system with in situ derivatization followed by gas chromatography-mass spectrometry for the determination of gaseous iodine-contai…
2008
Reactive iodine species have been suggested to play an important role in the atmosphere (e.g. tropospheric ozone depletion, coastal new particle formation). However, there still exist major uncertainties about their atmospheric chemistry, mostly due to the lack of analytical approaches for the accurate speciation of certain key compounds. In this study, 1,3,5-trimethoxybenzene (1,3,5-TMB)-coated denuder proved to be suitable for the differentiation between gaseous interhalogens (iodine monochloride (ICl), iodine monobromide (IBr)) and molecular iodine (I2) based on a selective collection/derivatization method. The results of the denuder sampling were compared with the results of impinger sa…
Three-Dimensional Calibration for Routine Analyses of Bromide and Nitrate Ions as Indicators of Groundwater Quality in Coastal Territories
2019
Nitrate and bromide ions are generally considered indicators of anthropogenic pollution and seawater intrusion, respectively, in the groundwater of coastal territories. The analysis of these species is generally carried out with routine chromatographic analyses which generally afford partially merged or poorly resolved peaks. In the present paper a simple method for the correct evaluation of their concentration in water is reported. This method does not imply utilization of other instruments or technologies, only the mathematical elaboration of the data obtained from routine analysis of standard solutions containing the two species. Standard binary solutions of nitrate and bromide ions at d…
Presence and distribution of the brown bear (Ursus arctos) in Friuli Venezia Giulia, from 2004 to 2011, through the non-invasive genetic monitoring a…
2012
After having disappeared at the beginning of 1900, the brown bear has started in a late 1960s a slow process of recolonization of the north-eastern Alps, through an expansion of Dinaric population. At the end of the 1990s the University of Udine began the occasional monitoring of the species and from 2004 non-invasive genetic monitoring became systematic. In the last 8 years 217 hair traps have been activated in the region to monitore: Natisone Valleys, the Julian and Carnic Alps and Prealps. Twenty-six hair traps were monitored in all years, whereas 40 were observed only in 2004, 2007 and 2011. The 26 hair traps constantly monitored from 2004 to 2011 showed 17% of average success of hair’s…
1023 – Therapeutic drug-monitoring of bupropion for depression
2013
Introduction Therapeutic Drug-Monitoring (TDM) for bupropion is limited by bupropion's instability at room temperature and by the absence of a well-defined therapeutic reference range. Further it is unclear to what extent bupropion and its metabolites contribute to therapeutic effects, though hydroxybupropion seems to account for the major antidepressant effects. Aim The aim of this examination was to check if measurement of only hydroxybupropion is useful to guide the antidepressant therapy with bupropion. Methods Hydroxybupropion plasma levels were measured by high performance liquid chromatography with ultra violet detection and related to therapeutic effects measured by the Clinical Glo…