587 research outputs found
Candida milleri detected by Electronic Nose in tomato sauce
AbstractThe tomato sauce is a product of great importance for its massive production in Italy. Microbial contamination is a constant concern for the industries, causing severe economic losses, posing risks to consumersâ health and contributing to an enormous wasting of food. This work shows how the use of the Electronic Nose (EN) EOS 507C can be effective compare to the current procedures in the food production. EN composed of an array of thin film sensors, 6 Metal Oxide (MOX). All the samples were analyzed in parallel with classical chemical technique, like GC-MS with SPME
Development of a rapid and eco-friendly UHPLC analytical method for the detection of histamine in fish products
We developed, validated, and confirmed with proficiency tests a fast ultra-high-performance liquid chromatography with diode array detector (UHPLC-DAD) method to determine histamine in fish and fishery products. The proposed method consists of two successive solidâliquid extractions: one with a dilute solution of perchloric acid (6%) and the second only with water. The instrumental analysis with UHPLC provides a very fast run time (only 6 min) with a retention time of approximately 4 min, a limit of quantification (LOQ) of 7.2 mg kgâ1, a limit of detection (LOD) of 2.2 mg kgâ1, a recovery around 100%, a relative standard deviation (RSD%) between 0.5 and 1.4, and an r2 of calibration curve equal to 0.9995. The method detected optimal values of the validation parameters and required a limited number of reagents in comparison to other methods reported in the literature. Furthermore, the method could detect histamine in a very short time compared with other methods. This method, in addition to being validated, precise, specific, and accurate, avoids wasting time, money, and resources, and limits the use of organic solvents
Trace elements in stomach oil of Scopoli's shearwater (Calonectris diomedea) from Linosa's colony
Calonectris diomedea is a colonial Procellariiform breeding on Mediterranean islands. The stomach oil produced during chick rearing is a peculiar trait of this species. The composition of the stomach oil is likely to reflect the composition of the prey ingested and might reveal the contaminants uptake with prey becoming a possible tool for the marine pollution monitoring. We examined the concentration of 15 trace elements by ICP-MS and direct mercury analyser. The principal component analysis revealed a heterogeneous pattern of metal concentration, showing a significant separation between samples collected 20 and 70 days after hatching. The data obtained in this work give preliminary information on the feeding habits and breeding ecology of Linosa's colony of Scopoli's shearwater. The trace metals variability found suggest that the stomach oil may have a role as trophic markers to understand predator-prey relationships and to have evidence on the accumulation of pollutants in the latter
A knowledge base for the discovery of function, diagnostic potential and drug effects on cellular and extracellular miRNAs
Background: MicroRNAs (miRNAs) are small noncoding RNAs that play an important role in the regulation of various biological processes through their interaction with cellular mRNAs. A significant amount of miRNAs has been found in extracellular human body fluids (e.g. plasma and serum) and some circulating miRNAs in the blood have been successfully revealed as biomarkers for diseases including cardiovascular diseases and cancer. Released miRNAs do not necessarily reflect the abundance of miRNAs in the cell of origin. It is claimed that release of miRNAs from cells into blood and ductal fluids is selective and that the selection of released miRNAs may correlate with malignancy. Moreover, miRNAs play a significant role in pharmacogenomics by down-regulating genes that are important for drug function. In particular, the use of drugs should be taken into consideration while analyzing plasma miRNA levels as drug treatment. This may impair their employment as biomarkers. Description: We enriched our manually curated extracellular/circulating microRNAs database, miRandola, by providing (i) a systematic comparison of expression profiles of cellular and extracellular miRNAs, (ii) a miRNA targets enrichment analysis procedure, (iii) information on drugs and their effect on miRNA expression, obtained by applying a natural language processing algorithm to abstracts obtained from PubMed. Conclusions: This allows users to improve the knowledge about the function, diagnostic potential, and the drug effects on cellular and circulating miRNAs
Self-similarity and power-like tails in nonconservative kinetic models
In this paper, we discuss the large--time behavior of solution of a simple
kinetic model of Boltzmann--Maxwell type, such that the temperature is time
decreasing and/or time increasing. We show that, under the combined effects of
the nonlinearity and of the time--monotonicity of the temperature, the kinetic
model has non trivial quasi-stationary states with power law tails. In order to
do this we consider a suitable asymptotic limit of the model yielding a
Fokker-Planck equation for the distribution. The same idea is applied to
investigate the large-time behavior of an elementary kinetic model of economy
involving both exchanges between agents and increasing and/or decreasing of the
mean wealth. In this last case, the large-time behavior of the solution shows a
Pareto power law tail. Numerical results confirm the previous analysis
Etn@ref: a geodetic reference frame for Mt. Etna GPS networks
In volcanology, one of the most important instruments for scientific community interested in modelling the physical processes related to magma movements in the shallow crust is geodetic data. Since the end of the 1980s, GPS surveys and Continuous GPS stations (CGPS) have greatly improved the possibility to measure such movements with high time and space resolution. However, physical modelling requires that any external influence on the data, not directly related to the investigated quantity, must be filtered. One major tricky factor in determining a deformation field using GPS displacement vectors and velocities is the correct choice of a stable reference frame. In this work, using more than a decade of GPS measurements, we defined a local reference frame in order to refer the Mt. Etna ground deformation pattern to a rigid block. In particular, we estimated the Euler pole for the rigid block by minimizing, with a weighted least squares inversion, the adjustments to two horizontal components of GPS velocity at 13 âfiducialâ sites located within 350 km around Mt. Etna. The inversion inferred an Euler pole located at 38.450° N and -107.702° E and a rotation rate of 0.263 deg/Myr
Global regularity of weak solutions to quasilinear elliptic and parabolic equations with controlled growth
We establish global regularity for weak solutions to quasilinear divergence
form elliptic and parabolic equations over Lipschitz domains with controlled
growth conditions on low order terms. The leading coefficients belong to the
class of BMO functions with small mean oscillations with respect to .Comment: 24 pages, to be submitte
Performance of ALICE pixel prototypes in high energy beams
The two innermost layers of the ALICE inner tracking system are instrumented
with silicon pixel detectors. Single chip assembly prototypes of the ALICE
pixels have been tested in high energy particle beams at the CERN SPS.
Detection efficiency and spatial precision have been studied as a function of
the threshold and the track incidence angle. The experimental method, data
analysis and main results are presented.Comment: 10 pages, 9 figures, contribution to PIX2005 Workshop, Bonn
(Germany), 5-8 September 200
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