Search results for "Method"

Risque phytosanitaire (ARP) portant sur Fusarium oxysporum f. sp. cubense (agent pathogène responsable de la maladie de Panama) pour les départements…

2018

Risque phytosanitaire (ARP) portant sur [i]Fusarium oxysporum[/i] f. sp.[u] cubense[/u] (agent pathogène responsable de la maladie de Panama) pour les départements d'Outre-mer

Démarche statistique pour la sélection des indicateurs par Random Forests pour la surveillance de la qualité des sols

2013

The volume of data, and the large number of biological variables to be tested (one hundred), require analytical techniques, such asRandom Forests, which can overcome the problem of multi-colinearity for the selection of indicators, sensitive to various factors.Random Forests methodology is appropriate for the selection of the most discriminant variables. So, we searched for the best wayto select them, by bringing together all biological variables, representing the Microflora and Fauna. This approach focuses on impactindicators from the Bio2 program, indicators of flora and indicators of accumulation (snails) were not included.This work has been implemented on the three factors of discrimina…

Some aspects of the recovery of chlorinated residues (DDT-type compounds and PCB) from fish tissue by using different extraction methods

1974

Error estimation and reduction with cross correlations

2010

Besides the well-known effect of autocorrelations in time series of Monte Carlo simulation data resulting from the underlying Markov process, using the same data pool for computing various estimates entails additional cross correlations. This effect, if not properly taken into account, leads to systematically wrong error estimates for combined quantities. Using a straightforward recipe of data analysis employing the jackknife or similar resampling techniques, such problems can be avoided. In addition, a covariance analysis allows for the formulation of optimal estimators with often significantly reduced variance as compared to more conventional averages.

Ready Access to Proquinazid Haptens via Cross-Coupling Chemistry for Antibody Generation and Immunoassay Development.

2015

17 pages, 4 tables, 5 figures.-- Publisher's PDF

Determination of trimethoprim by the linear absorbances method

1995

The determination of trimethoprim in the presence of dyphylline, proxyphylline, theophylline and caffeine by the linear absorbances method is described. Collinear couples of wavelengths, for the interfering dyphylline-proxyphylline-theophylline-caffeine system (in H2SO4, 0.05 mol/L), are provided in order to allow the determination of the analyte in the presence of these interfering substances.

Computer simulations for bioequivalence trials: Selection of analyte in BCS class II and IV drugs with first-pass metabolism, two metabolic pathways …

2018

A semi-physiological two compartment pharmacokinetic model with two active metabolites (primary (PM) and secondary metabolites (SM)) with saturable and non-saturable pre-systemic efflux transporter, intestinal and hepatic metabolism has been developed. The aim of this work is to explore in several scenarios which analyte (parent drug or any of the metabolites) is the most sensitive to changes in drug product performance (i.e. differences in in vivo dissolution) and to make recommendations based on the simulations outcome. A total of 128 scenarios (2 Biopharmaceutics Classification System (BCS) drug types, 2 levels of KM Pgp, in 4 metabolic scenarios at 2 dose levels in 4 quality levels of t…

Quantitative colorimetric analysis of some inorganic salts using digital photography

2011

An analytical imaging approach to the quantitation of dissolved chemical species absorbed in the visible spectral region is reported. The approach uses digital images of a series of standard solutions of the target substance and their processing with appropriate software to assign a numeric value to each standard in terms of color intensity. Such a value is directly proportional to the analyte concentration and allows the construction of a calibration graph. The results thus obtained are compared with those provided by the classical spectrophotometricmethod used to run calibration curves for colored substances. The chemical imaging technique is relative simple and affordable; in fact, it ca…

Analysis of basic drugs by liquid chromatography with environmentally friendly mobile phases in pharmaceutical formulations

2017

Abstract Basic drugs are positively charged in the usual working pH (2–8) in reversed-phase liquid chromatography. This gives rise to a strong association with the residual ionized silanols in conventional silica-based stationary phases, which is translated in poor peak shape and high consumption of organic solvent to get appropriate retention times. Micellar mobile phases containing surfactants give rise to modified stationary phases, where silanols are masked, improving the peak shape. However, mobile phases containing the anionic surfactant sodium dodecyl sulfate (SDS) require a small amount of organic solvent to conveniently decrease the retention of cationic analytes. An alternative is…

Assessment of oxidative damage to proteins and DNA in urine of newborn infants by a validated UPLC-MS/MS approach

2014

The assessment of oxidative stress is highly relevant in clinical Perinatology as it is associated to adverse outcomes in newborn infants. This study summarizes results from the validation of an Ultra Performance Liquid Chromatography-tandem Mass Spectrometry (UPLC-MS/MS) method for the simultaneous quantification of the urinary concentrations of a set of endogenous biomarkers, capable to provide a valid snapshot of the oxidative stress status applicable in human clinical trials, especially in the field of Perinatology. The set of analytes included are phenylalanine (Phe), para-tyrosine (p-Tyr), ortho-tyrosine (o-Tyr), meta-tyrosine (m-Tyr), 3-NO2-tyrosine (3NO(2)-Tyr), 3-Cl-tyrosine (3Cl-T…