Search results for "repeatability"
showing 10 items of 214 documents
Design and performance testing of a real-time PCR assay for sensitive and reliable direct quantification of Brettanomyces in wine
2009
International audience; Because the yeast Brettanomyces produces volatile phenols and acetic acid, it is responsible for wine spoilage. The uncontrolled accumulation of these molecules in wine leads to sensorial defects that compromise wine quality, The need for a rapid, specific, sensitive and reliable method to detect this spoilage yeast has increased over the last decade. All these requirements are met by real-time PCR. We here propose improvements of existing methods to enhance the robustness of the assay. Six different protocols to isolate DNA from a wine and three PCR mix compositions were tested, and the best method was selected. Insoluble PVPP addition during DNA extraction by a cla…
A novel prototype to closely mimic mastication for in vitro dynamic measurements of flavour release
2005
International audience; Flavour release during eating of a food depends upon many parameters that can hardly be managed. In-vivo measurements by the APCI MS-nose method allowed temporal sensory evaluation and flavour release data to be directly correlated, but several limitations have frequently been reported. These were: high inter-individual variability, low repeatability of measurements, and weak experiment throughput due to panellists' exhaustion. To overcome most of these limitations, the use of an artificial mouth for online mesurement of flavour release is recommended. However, the systems used in previous reports were limited in terms of reproducing in-vivo oral functions and parame…
Preparation and characterization of hexyl methacrylate monolithic columns for CEC
2008
The preparation of hexyl methacrylate (HMA) monolithic columns for CEC separations has been investigated with two initiation systems: (i) ammonium peroxodisulphate and TEMED to activate the polymerization reaction, and (ii) by thermal initiation with AIBN. For both initiators, the influence of composition of porogenic solvent on morphological and chromatographic properties of monoliths was investigated. Two porogenic solvent systems, aqueous and non-aqueous media, were also studied for monolithic beds polymerized with AIBN. Under optimal conditions, low minimum plate heights (9.6 mum for peroxodisulphate, 8.4 and 10.0 mum for AIBN in aqueous and non-aqueous porogenic solvents, respectively)…
Reproducibility of FFR
2016
This chapter describes the repeatability of FFR assessments using IC and IV infusions of Adenosine. Further, it demonstrates that is possible to assess FFR with a diagnostic catheter.
Evaluation of olfactory intensity : comparative study of two methods
2004
Two experimental procedures recommended for the evaluation of the psychophysical characteristics of odorous compounds, olfactory matching with the 1-butanol scale and cross-modality matching with the finger span are compared. The intensity of ethyl butyrate and guaiacol solutions presented at four different concentration levels was evaluated by a panel of sixteen subjects over five repetitions using the two methods. Each stimulus was delivered to the subject from a Teflon bag through a nose-shaped glass sniffing port. The discrimination ability, repeatability, panel homogeneity and within-subject variability of the methods were assessed. Results indicate that with both methods, subjects wer…
Chromatographic determination of caffeine in pharmaceutical formulations using micellar mobile phases
1996
An HPLC procedure is described for the determination of caffeine in pharmaceutical preparations. A Spherisorb octadecylsilane ODS-2 C18 analytical column and spectrophotometric detection at 273 nm were used. The chromatographic behaviour of caffeine with different micellar eluents containing sodium dodecyl sulphate (SDS) is described. The determination of caffeine in pharmaceutical preparations was performed by use of a mobile phase containing 0.05 M sodium dodecylsulphate (SDS) and 1.5% propanol at pH7. At a 6.0 μg mL−1 concentration level the peak area and peak height repeatability were 2.6 and 2.4%, respectively. The application of the proposed method to the analysis of five pharmaceutic…
Multicommutation-NIR determination of Hexythiazox in pesticide formulations.
2006
A multicommutated flow-system was designed in order to increase analytical throughput and for controlling thermal effects on the NIR spectra for determination of Hexythiazox in pesticide formulations. An on-line standard addition was carried out showing the versatility and repeatability of multicommutation for the on-line mixing and dilution of solutions. Results obtained for commercial samples were statistically comparable with those obtained by an HPLC-reference method. Multicommutation-NIR allows the analysis of 52 samples per hour, in front of the 30 samples per hour analyzed by the NIR-batch procedure and the 7 samples per hour analyzed by HPLC-reference method.
Determination of SiO 2 in lime mud by gravimetry
1999
A simple and rapid method for the determination of SiO2 in lime mud used in current sulfate pulping practice is reported. The lime mud samples are treated three times with 2.5 mL of 6 mol/L hydrochloric acid. The samples are nearly evaporated to dryness two times and the third time to complete dryness. To determine the exact SiO2 content of the residue, it is treated with an excess of concentrated hydrofluoric acid and a little hydrochloric acid, and the silica is expelled as volatile silicon tetrafluoride. The sample treatments take about 1.5 h and the heating periods take a total of about 3.5 h. The SiO2 results were evaluated by analyzing National Institute of Standards and Technology St…
The application of phospholipid removal columns and ultra-high performance liquid chromatography-tandem quadrupole mass spectrometry for quantificati…
2016
In this study a robust and sensitive method based on a proposed sample purification procedure, using zirconia-coated Phree™ columns and analysis by ultra-high performance liquid chromatography with triple quadrupole tandem mass spectrometry are presented for the assessment of multi-class antibiotics in farmed fish species. The sample preparation procedure benefited from combined precipitation of proteins and selective removal of phospholipids by Phree™ columns, resulting in a high sensitivity of the method (LOQ 0.3-9mgkg(-1)). The in-house validation results (precision, repeatability, decision limit CCα, detection capability CCβ, etc.) indicate that the elaborated method is fully suitable f…
Isometric endurance test of the cervical flexor muscles - Reliability and normative reference values.
2017
Abstract Objective To obtain reference values for the isometric endurance test (IET) of the cervical flexor muscles, investigate its reproducibility, and compare the results with the maximal isometric strength test (MIST) of the cervical flexor muscles. Design Cross-sectional non-comparative study with single group repeated measurements. Methods Altogether 219 healthy females aged 20–59 years volunteered to participate in the study. The IET was performed in the supine position and MIST seated. The reproducibility was evaluated by the intraclass correlation coefficient (ICC) and an analysis described by Bland and Altman. The relationship between the two measuring methods was evaluated by Pea…