Search results for "Reaction"
showing 10 items of 6134 documents
Quantitative detection of viable foodborne E. coli O157:H7, Listeria monocytogenes and Salmonella in fresh-cut vegetables combining propidium monoazi…
2012
Abstract The increase of foodborne outbreaks associated with fresh vegetables has highlighted the importance of developing rapid and specific methods for the detection and quantification of foodborne pathogens. In this sense, real-time PCR (qPCR) fulfills these requirements although it may detect dead cells. Recently, a potential strategy to specifically detect viable cells has been proposed relying on the use of DNA binding molecules as sample pretreatment previous to the qPCR. In this study propidium monoazide (PMA) and reagent D, combined with qPCR, were evaluated for the detection and quantification of viable Escherichia coli O157:H7, Salmonella and Listeria monocytogenes. Initially, th…
APPLICATION OF REAL-TIME POLYMERASE CHAIN REACTION FOR RAPID DETERMINATION OFSALMONELLAIN RESTAURANT FOODS
2008
Several foods have been identified as frequently or occasionally contaminated with Salmonella, such as eggs, raw milk and all raw foods of animal origin that may carry salmonella and other bacteria. Salmonellosis is the most common food-borne illness, but it is usually preventable according to the implementation of a food safety system that includes Hazard Analysis and Critical Control Point. In this study, 96 food samples of the University restaurant of Valencia (Spain) were divided into four groups: first course; main course; accompaniment; and dessert, and were analyzed simultaneously with classical and fluorogenic polymerase chain reaction microbiological analysis. Neither of the proced…
A single method for recovery and concentration of enteric viruses and bacteria from fresh-cut vegetables
2011
Fresh-cut vegetables are prone to be contaminated with foodborne pathogens during growth, harvest, transport and further processing and handling. As most of these products are generally eaten raw or mildly treated, there is an increase in the number of outbreaks caused by viruses and bacteria associated with fresh vegetables. Foodborne pathogens are usually present at very low levels and have to be concentrated (i.e. viruses) or enriched (i.e. bacteria) to enhance their detection. With this aim, a rapid concentration method has been developed for the simultaneous recovery of hepatitis A virus (HAV), norovirus (NV), murine norovirus (MNV) as a surrogate for NV, Escherichia coli O157:H7, List…
The gas-phase chemiionization reaction between samarium and oxygen atoms: A theoretical study
2004
The Sm + O chemiionization reaction has been investigated theoretically using a method that allows for correlation and relativistic effects. Potential energy curves have been calculated for several electronic states of SmO and SmO+. Comparison with available spectroscopic and thermodynamic values for these species is reported and a mechanism for the chemiionization reaction Sm + O is proposed. The importance of spin–orbit coupling in the excited states of SmO, in allowing this chemiionization reaction to take place, has been revealed by these calculations. This paper shows the metal-plus-oxidant chemiionization reaction.
Analysis of primary aliphatic short-chain monoamines by LC in water samples
2003
Abstract Several derivatization procedures with o-phthaldialdehyde-N-acetylcysteine (OPA-NAC) were compared for a rapid analysis of primary aliphatic short-chain monoamines in water samples by HPLC using a LiChorospher analytical separation column (100RP18 125 mm ×4 mm i.d., 5 μm). Both the solution and the solid-support assisted off-line derivatization on C18 SPE cartridges were inadequate options because of beginning degradation processes of the instable isoindol derivatives during their transfer to the analytical column. This problem was precluded with the on-column or solid-support assisted on-line derivatization. In the last mentioned procedure, the derivatization took place in a Hype…
A new method for fluoride determination by using fluorophores and dyes anchored onto MCM-41
2002
A new colourimetric and fluorimetric method for fluoride determination in aqueous samples based on the specific reaction between fluoride and silica has been developed and applied on real samples. Descalzo Lopez, Ana Belen, adeslo@alumni.uv.es ; El Haskouri, Jamal, Jamal.Haskouri@uv.es ; Beltran Porter, Daniel, Daniel.Beltran@uv.es ; Amoros del Toro, Pedro Jose, Pedro.Amoros@uv.es
Ighv Mutational Status By Deep Next Generation Sequencing Refines Ighv Sanger Sequencing Classification in Patients with Chronic Lymphocytic Leukaemia
2019
Introduction: Determination of the mutational status of rearranged immunoglobulin heavy chain variable (IgHV) genes in patients with Chronic Lymphocytic Leukaemia (CLL), is considered one of the most important prognostic factors: patients with unmutated IgHV (UM; ≥98% of identity to the germline) genes have a more aggressive disease course and develop more frequently unfavourable genetic deletions or mutations than patients with mutated IgHV (M; ≤98%). Mutational status, is currently determined by Sanger sequencing (Sseq) that allows the analysis of the major clone, however, international guidelines recommend caution in assigning mutational status in cases with "Borderline" IgHV identity (9…
Silk fibroin scaffolds enhance cell commitment of adult rat cardiac progenitor cells.
2015
The use of three-dimensional (3D) cultures may induce cardiac progenitor cells to synthesize their own extracellular matrix (ECM) and sarcomeric proteins to initiate cardiac differentiation. 3D cultures grown on synthetic scaffolds may favour the implantation and survival of stem cells for cell therapy when pharmacological therapies are not efficient in curing cardiovascular diseases and when organ transplantation remains the only treatment able to rescue the patient’s life. Silk fibroin-based scaffolds may be used to increase cell affinity to biomaterials and may be chemically modified to improve cell adhesion. In the present study, porous, partially orientated and electrospun nanometric n…
Differential cross section for the reaction 2H(γ, p)n from 133 to 158 MeV
1991
The cross section for the reaction 2H(γ, p)n has been measured at laboratory photon energies Eγ = 133−158 MeV and c.m. angles between 30° and 150°. The reaction was induced by a tagged bremsstrahlung photon beam incident on a liquid deuterium target. The uncertainty in the absolute cross sections is ⩽ 5%. There is now reasonable agreement between recent measurements in this energy region and the overall data set now defines the cross section sufficiently well to provide a test of current models of the reaction.
Vibration effect on ball score test in international vs. national level table tennis
2018
In table tennis, motor skills are crucial for discriminating player level. However, there is a dearth of studies exploring the impact of a vibrational stimulus on performance. Thirty-four male players (age 25 +/- 2 years ; body mass index, BMI 23.4 +/- 1.2 kg.m(-2)) participated in the study. Seventeen played at international level (IL), while the remaining 17 played at national level (NL). The participants underwent a ball-handling test, the ball score, before (PRE) and after (POST) a vibrational stimulus. Intra-class correlation (ICC) for the ball score result showed good reliability (ICC 0.87 for IL and 0.80 for NL). Repeated measures ANOVA showed differences between groups for ball scor…