Search results for "indicators."
showing 10 items of 516 documents
Optimization of selenium determination in human milk and whole blood by flow injection hydride atomic absorption spectrometry.
1998
abstract A flow injection hydride atomic absorption spectrometry (FI-HAAS) method was developed for determining selenium in human milk and whole blood after microwave digestion of the sample. The sample (2 mL human milk or 0.25 mL blood) was introduced into the microwave vessel with 1.5 mL HN03 and 0.25 mL H202 and 300 W (4 min) and 600 W (4 min) were applied. The digestion was completed by heating to 140 C (2-3 h). Se (VI) was reduced to Se (IV) with hydrochloric acid. The instrumental conditions for FI-HAAS (concentrations of reducing agent and carrier acid, flow rate of argon carrier gas, and sample volume injected) were optimized. The detection limit of the proposed method was 0.23 ng/m…
Beads of Acryloylated Polyaminoacidic Matrices Containing 5-Fluorouracil for Drug Delivery
2002
Spherical polymeric microparticles have been prepared by a reverse phase suspension polymerization technique. The starting polymer was alpha,beta-poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA), partially derivatized with glycidylmethacrylate (GMA). PHEA-GMA copolymer (PHG) was crosslinked in the presence of N,N'-dimethylacrylamide (DMAA) or N,N'-ethylenebisacrylamide (EBA). 5-fluorouracil was incorporated into PHG-DMAA or PHG-EBA beads both during and after the crosslinking process. Swelling studies revealed a high affinity toward aqueous medium, influenced by the presence of 5-fluorouracil. The in vitro release study showed that the release rate depends on the chemical structure of the beads…
Anàlisi crítica d’aplicacions de lectura per a infants: paràmetres i indicadors
2018
Les aplicacions de lectura digital infantil han evolucionat considerablement al llarg dels últims anys. Tanmateix, segueixen sent les grans oblidades en informes i estadístiques sobre la producció editorial i més encara dins del sector digital, cosa que origina un fenomen d’infoxicació en què el mediador es troba amb pocs criteris que faciliten la selecció d’aquest nou tipus de continguts. Aquesta investigació presenta els resultats de l’anàlisi de tretze aplicacions de lectura en les seues dimensions de forma i contingut. Alhora, s’hi observen trets com ara el mode d’adquisició, la privacitat, l’organització de continguts o la personalització. Finalment, reflexionarem sobre l’adequació del…
Overview of pesticide use in Moroccan apple orchards and its effects on the environment
2021
International audience; The cultivation of apple trees needs to use phytosanitary products, which are used in an irrational way by certain farmers. The harmful effects of pesticides result mainly from their persistence in the environment. Several studies have been carried out to estimate the pesticide residues and assess their effects on soil microorganisms and aquatic organisms. The results of these studies have revealed a harmful effect on these bioindicators. Therefore, a disruption in their growth and reproduction, an increase in their mortality, and a decrease in their fertility have been proven. In addition, a considerable reduction in the number and diversity of soil microorganisms a…
Visually low-impacting methods for the measurement of parameters related to IAQ risk indicators in exhibition halls
2021
Microclimate for cultural heritage plays a fundamental role in the degradation process of artefacts exhibited in museums. Generally, the Indoor Air Quality (IAQ) monitoring inside museums is based on conventional measurements of thermo-hygrometry parameters and longtime averaged measurements of atmospheric pollutants’ concentration. Unfortunately, all these approaches require electric supply and are usually characterized by a noticeable visual impact on the exhibition space, which clearly negatively affects the visitors’ experience. This paper intends to revisit and discuss a methodology (and its test application on field, to estimate the risk of damage of three artefacts displayed in an ol…
An innovative approach to manage uncertainties and stock diversity in the EPBD cost-optimal methodology
2018
The EU Energy Performance of Buildings Directive (EPBD) 2010/31/EU is a step in the right direction to promote near zero energy buildings (NZEB) in a step-wise manner, starting with minimum energy performance and cost optimal thresholds for “reference buildings” (RBs) for each category. Nevertheless, a standard method for defining RBs does not exist, which led to a great divergence between MS in the level of detail used to define RBs for the EPBD cost-optimal analysis. Such lack of harmonisation between MS is further evident given the resulting large discrepancies in energy performance indicators even between countries having similar climate. Furthermore, discrepancies of 30% or higher betw…
Activation of nitric oxide signaling by the rheumatoid arthritis shared epitope
2006
Objective. Susceptibility to rheumatoid arthritis (RA) is closely associated with HLA–DRB1 alleles encoding a shared epitope (SE) in positions 70–74 of the HLA–DR chain. The mechanistic basis for this association is unknown. Given the proposed pathogenic role of nitric oxide (NO) in RA, this study was undertaken to examine whether the SE can trigger NO signaling events. Methods. The intracellular levels of NO were measured with the fluorescent NO probe 4,5diaminofluorescein diacetate and by the 2,3diaminonaphthalene method. NO synthase activity was determined by measuring the rate of conversion of radioactive arginine to citrulline. Levels of cGMP were measured with a commercial enzyme-link…
Delivering Inorganic and Organic Reagents and Enzymes from Zein and Developing Optical Sensors.
2018
Nowadays, interest in using environmentally friendly materials is increasing in many fields. However, the rational design of sensors with biodegradable materials is a challenge. The main aim of this work is to show the possibility of using zein, a protein from corn, as a biodegradable and low-cost material for immobilizing, stabilizing, and delivering different kind of reagents for developing optical sensors. Enzymes, metallic salts, and aromatic and small organic compounds were tested. In addition, different techniques of immobilization, entrapment and adsorption, were used, and different formats, such as solid devices and also multiwell platforms, were proposed. The capacity of zein for i…
Application of viability PCR to discriminate the infectivity of hepatitis A virus in food samples.
2015
Abstract Transmitted through the fecal–oral route, the hepatitis A virus (HAV) is acquired primarily through close personal contact and foodborne transmission. HAV detection in food is mainly carried out by quantitative RT-PCR (RT-qPCR). The discrimination of infectious and inactivated viruses remains a key obstacle when using RT-qPCR to quantify enteric viruses in food samples. Initially, viability dyes, propidium monoazide (PMA) and ethidium monoazide (EMA), were evaluated for the detection and quantification of infectious HAV in lettuce wash water. Results showed that PMA combined with 0.5% Triton X-100 (Triton) was the best pretreatment to assess HAV infectivity and completely eliminate…
Proteomic analysis of Kveim reagent identifies targets of cellular immunity in sarcoidosis
2017
Background Kveim-reagent (Kv) skin testing was a historical method of diagnosing sarcoidosis. Intradermal injection of treated sarcoidosis spleen tissue resulted in a granuloma response at injection site by 4–6 weeks. Previous work indicates proteins as the possible trigger of this reaction. We aimed to identify Kv-specific proteins and characterise the ex vivo response of Peripheral Blood Mononuclear Cells (PBMCs) from sarcoidosis, tuberculosis and healthy control patients when stimulated with both Kv and selected Kv-specific proteins. Methods Kv extracts were separated by 1D-SDS-PAGE and 2D-DIGE and then underwent mass spectrometric analysis for protein identification. Sarcoidosis and con…