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1.
Molecules ; 28(21)2023 Oct 26.
Article de Anglais | MEDLINE | ID: mdl-37959703

RÉSUMÉ

The purpose of this study was to investigate the synthesis of iron oxide nanoparticles under two different conditions, namely high and low gas flow rates, using laser pyrolysis and to examine the influence of laser power. The attained nanoparticles have been characterised regarding their stability and hydrodynamic dimensions by dispersive light scattering analysis (DLS), structure-X-ray diffraction (XRD), elemental composition-energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), and morpho-structural characterisation achieved by transmission electron microscopy (TEM) and selected-area electron diffraction (SAED). For a better understanding of the laser power influence, the residence time was also calculated.

2.
Microsc Microanal ; 29(3): 1137-1152, 2023 Jun 09.
Article de Anglais | MEDLINE | ID: mdl-37749699

RÉSUMÉ

The use of atom probe tomography (APT) for mineral analysis is contributing to fundamental studies in Earth Sciences. Meanwhile, the need for standardization of this technique is becoming evident. Pending the use of mineral standards, the optimization of analysis parameters is needed to facilitate the study of different mineral groups in terms of data collection and quality. The laser pulse rate and energy are variables that highly affect the atom evaporation process occurring during APT analysis, and their testing is important to forecast mineral behavior and obtain the best possible data. In this study, five minerals representative of major groups (albite, As-pyrite, barite, olivine, and monazite) were analyzed over a range of laser pulse energies (10-50 pJ) and rates (100-250 kHz) to assess output parameter quality and evaluate compositional estimate stoichiometry. Among the studied minerals, As-pyrite, with the higher thermal conductivity and lower band gap, was the most affected by the laser pulse variation. Chemical composition estimates equal or close to the general chemical formula were achieved for monazite and As-pyrite. The analysis of multihit events has proved to be the best strategy to verify the efficacy of the evaporation process and to evaluate the best laser pulse setting for minerals.

3.
Adv Exp Med Biol ; 1192: 283-296, 2019.
Article de Anglais | MEDLINE | ID: mdl-31705500

RÉSUMÉ

Animal research in psychiatry suffers from a poor translational value. It is the same for all other disciplines. Our purpose in this chapter is therefore to highlight all the parameters that can lead to a non-reproducibility of interlaboratory experiments as well as intralaboratory. This is to point out the experimental parameters that are likely to lead to bias. Parameters are essentially: breeding conditions, animal strains, housing, handling, illumination, weather conditions, age, and the actual experimental conditions. Controlling these parameters is not enough if there is no consensus of the scientific community to implement them in a standardized way. However, it is possible to improve the translational concept by taking stock of what has been operational without forgetting to standardize as much as possible the essential parameters of behavioral research. Now there are calls to take a different approach to animal experimentation, by asking not what was controlled in an experiment, but what was ignored. This new school of thinking has been termed "therioepistemology"; the study of how knowledge is gained from animal research. The focus is on what's been ignored in an animal data set, why it's been ignored, and how it affects the model or experiment.


Sujet(s)
Expérimentation animale , Psychiatrie , Animaux , Biais (épidémiologie) , Sélection , Savoir
4.
Adv Drug Deliv Rev ; 151-152: 152-168, 2019.
Article de Anglais | MEDLINE | ID: mdl-30615917

RÉSUMÉ

The interactions of nanomedicines with biological environments is heavily influenced by their physicochemical properties. Formulation design and optimization are therefore key steps towards successful nanomedicine development. Unfortunately, detailed assessment of nanomedicine formulations, at a macromolecular level, in rodents is severely limited by the restricted imaging possibilities within these animals. Moreover, rodent in vivo studies are time consuming and expensive, limiting the number of formulations that can be practically assessed in any one study. Consequently, screening and optimisation of nanomedicine formulations is most commonly performed in surrogate biological model systems, such as human-derived cell cultures. However, despite the time and cost advantages of classical in vitro models, these artificial systems fail to reflect and mimic the complex biological situation a nanomedicine will encounter in vivo. This has acutely hampered the selection of potentially successful nanomedicines for subsequent rodent in vivo studies. Recently, zebrafish have emerged as a promising in vivo model, within nanomedicine development pipelines, by offering opportunities to quickly screen nanomedicines under in vivo conditions and in a cost-effective manner so as to bridge the current gap between in vitro and rodent studies. In this review, we outline several advantageous features of the zebrafish model, such as biological conservation, imaging modalities, availability of genetic tools and disease models, as well as their various applications in nanomedicine development. Critical experimental parameters are discussed and the most beneficial applications of the zebrafish model, in the context of nanomedicine development, are highlighted.


Sujet(s)
Modèles animaux de maladie humaine , Nanomédecine , Tumeurs/traitement médicamenteux , Animaux , Systèmes de délivrance de médicaments , Évaluation préclinique de médicament , Thérapie génétique , Nanoparticules/composition chimique , Danio zébré
5.
Waste Manag ; 73: 54-61, 2018 Mar.
Article de Anglais | MEDLINE | ID: mdl-29249309

RÉSUMÉ

Recycling and reuse of automotive plastics have elicited global attention due to the increasing number of end-of-life vehicles. Through the single-factor experiment, a high-voltage triboelectrostatic sorting device was developed to separate polypropylene (PP), polyurethane (PU), and polyvinylchloride (PVC) in a plastic mixture commonly used in exterior and interior parts of passenger vehicles. Products of PP, PU, and PVC were obtained after two-stage separation; their purity exceeded 95%, and their productivities were 74%, 94%, and 41%, respectively. The appropriate experimental parameters for high voltage level and rotational speed of the friction drum and cylinder electrode for the first stage of separation were 35 kV, 30 rpm, and 35 rpm, respectively, and the parameters for the second stage of separation were 35 kV, 30 rpm, and 25 rpm, respectively. Results showed that hybrid materials should be selected based on the triboelectric series to separate three-component plastic mixtures feasibly.


Sujet(s)
Polypropylènes/composition chimique , Polyuréthanes/composition chimique , Poly(chlorure de vinyle)/composition chimique , Recyclage , Automobiles , Matières plastiques
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