24 results match your criteria: "Universite de Pau et des Pays de l'Adour (UPPA)[Affiliation]"

Toxic and non-toxic cyanobacterial biomass as a resource for sustainable agriculture: A lettuce cultivation experiment.

Environ Res

December 2024

Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Porto University, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos S/n, 4450-208, Matosinhos, Portugal; ESS, Polytechnic of Porto (ESS|P.PORTO), Rua Dr. António Bernardino de Almeida 400, 4200-072, Porto, Portugal. Electronic address:

Cyanobacteria represent a promising resource for sustainable agriculture, as they have demonstrated the ability to restore soil fertility even after death and decay. However, several cyanobacteria can also release secondary metabolites, such as cyanotoxins, which may compromise the quality of agricultural products and pose a potential risk to human health. Depending on the concentration of exposure, few studies reported deleterious effects on plant species when irrigated with cylindrospermopsin (CYN) contaminated water, impairing plant growth and leading to food product contamination, while other studies show promoting effects on plant yield.

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Article Synopsis
  • Otoliths are used to understand fish life-history and habitat, but the process of how they form is not well understood, which can lead to research errors in ecology and conservation efforts.
  • The study examined how different elements incorporate into otoliths of European hake and sea bass, revealing clear differences in element concentrations between the two sides of the otolith, indicating a complex mineralization process.
  • The findings emphasize the need for more research into otolith formation and suggest careful sampling and analytical practices to avoid biases in future studies.
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Coiled tube field-flow fractionation (CTFFF) is currently applied to environmental and material studies. In the present work, a novel zone elution mode in CTFFF has been proposed and developed. Zone elution mode is based on the separation of particles by stepwise decreasing the flow rate of the carrier fluid and their subsequent elution at a constant flow rate.

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A recurring feature of oceanic archipelagos is the presence of adaptive radiations that generate endemic, species-rich clades that can offer outstanding insight into the links between ecology and evolution. Recent developments in evolutionary genomics have contributed towards solving long-standing questions at this interface. Using a comprehensive literature search, we identify studies spanning 19 oceanic archipelagos and 110 putative adaptive radiations, but find that most of these radiations have not yet been investigated from an evolutionary genomics perspective.

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Biomats that flourished in a fumarole located on the geothermal site Los Azufres (Mexico) were used as inocula to select aerobic and sulfate-reducing bacteria consortia for studying their capacity to reduce hexavalent chromium [Cr(VI)], aiming to use these consortia in biotransformation technologies. The sample site is characterized by slightly warm (nearly 27 [Formula: see text]C), acid (pH 3) and about hypoxic (1.8 mg L[Formula: see text] of dissolved oxygen) conditions.

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Purpose: The aim of this study was to investigate the presence and chemical forms of residual gadolinium (Gd) in rat brain after a single dose of Gd-based contrast agent.

Methods: Four groups of healthy rats (2 sacrifice time-points, n = 10/group, 80 rats in total) were randomized to receive a single intravenous injection of 1 of the 3 Gd-based contrast agents (GBCAs) (gadoterate meglumine, gadobenate dimeglumine, or gadodiamide) or the same volume of 0.9% saline solution.

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Nanoparticles (NPs) in the environment have a potential risk for human health and the ecosystem due to their ubiquity, specific characteristics, and properties (extreme mobility in the environment, abilities to accumulate of toxic elements and penetrate into living organisms). There is still a gap in studies on the chemical composition of natural NPs. The main reason is the difficulty to recover NPs, which may represent only one-thousandth or less of the bulk environmental sample, for further dimensional and quantitative characterization.

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In the frame of the Diffusion Coefficient Measurements in ternary mIXtures 4 (DCMIX4) project the thermodiffusion experiments were conducted on the International Space Station (ISS) in the Selectable Optical Diagnostics Instrument (SODI) which is on orbit since 2009. We describe the results of the preliminary analysis of images downloaded during the execution of DCMIX4 in order to check the quality of the running experiments and, if needed, adjust the experiment parameters for the following runs. The quick analysis of raw data showed that they are meaningful and will allow to obtain the transport coefficients of examined ternary and binary mixtures.

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A chemical modification by grafting alkyl chains using an octanal (C8) on chitosan was conducted with the aim to improve its water resistance for bonding applications. The chemical structure of the modified polymers was determined by NMR analyses revealing two alkylation degrees (10 and 15%). In this study, the flow properties of alkyl-chitosans were also evaluated.

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Colloidal mobilization from soil and transport of uranium in (sub)-surface waters.

Environ Sci Pollut Res Int

February 2019

Université de Pau et des Pays de l'Adour (UPPA), Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux (IPREM), UMR 5254 UPPA-CNRS, Hélioparc, 2 Avenue Angot, 64000, Pau, France.

An analytical methodology was developed to characterize the colloidal distribution of trace elements of interest in environmental waters sampled in a same site and enables the different colloidal distributions from waters to be compared. The purpose was to provide consistent information related to the origin and nature of colloids responsible for the transport of trace element(s). The work was motivated by the observed enhanced mobility of uranium in soil.

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Directed Self-Assembly in "Breath Figure" Templating of Melamine-Based Amphiphilic Copolymers: Effect of Hydrophilic End-Chain on Honeycomb Film Formation and Wetting.

Chemistry

January 2018

Institut des Sciences Analytiques et de Physico-Chimie pour, l'Environnement et les Matériaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA), CNRS UMR 5254, Hélioparc, 2 avenue Angot, 64053, Pau Cedex 9, France.

Amphiphilic copolymers are widely used in the fabrication of hierarchically honeycomb-structured films through a "breath figure" (BF) process because the hydrophilic block plays a key role in stabilising water templating. However, the hydrophilic monomers reported are mainly confined to acrylic acid and its derivatives, which largely limits understanding of the formation of BF arrays and the introduction of additional functions on porous films. The relationship between polymer composition, film microstructure and surface properties are also less documented.

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Speed performance during gait initiation is known to be dependent on the capacity of the central nervous system to generate efficient anticipatory postural adjustments (APA). According to the posturo-kinetic capacity (PKC) concept, any factor enhancing postural chain mobility and especially spine mobility, may facilitate the development of APA and thus speed performance. "Spinal Manipulative Therapy High-Velocity, Low-Amplitude" (SMT-HVLA) is a healing technique applied to the spine which is routinely used by healthcare practitioners to improve spine mobility.

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Design and Cellular Fate of Bioinspired Au-Ag Nanoshells@Hybrid Silica Nanoparticles.

Langmuir

October 2016

Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux (IPREM)-UMR CNRS/UPPA 5254, Equipe de Chimie Physique (ECP), Université de Pau et des Pays de l'Adour (UPPA), Technopôle Hélioparc Pau Pyrénées , 2, Avenue du Président Pierre Angot, 64053 Pau Cedex 09, France.

Silica-coated gold-silver alloy nanoshells were obtained via a bioinspired approach using gelatin and poly-l-lysine (PLL) as biotemplates for the interfacial condensation of sodium silicate solutions. X-ray photoelectron spectroscopy was used as an efficient tool for the in-depth and complete characterization of the chemical features of nanoparticles during the whole synthetic process. Cytotoxicity assays using HaCaT cells evidenced the detrimental effect of the gelatin nanocoating and significant induction of late apoptosis after silicification.

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Speciation of Selenium in Selenium-Enriched Sunflower Oil by High-Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry/Electrospray-Orbitrap Tandem Mass Spectrometry.

J Agric Food Chem

June 2016

Laboratoire de Chimie Analytique Bio-inorganique et Environnement (LCABIE), Institut des Sciences Analytiques et de Physicochimie pour l'Environnement et les Matériaux (IPREM), Centre National de la Recherche Scientifique (CNRS)/Université de Pau et des Pays de l'Adour (UPPA), Hélioparc, 2 Avenue du Président Pierre Angot, 64053 Pau, France.

The reaction of sunflower oil with selenite produces a complex mixture of selenitriglycerides with antioxidant and anticancer properties. To obtain insight into the identity and characteristics of the species formed, an analytical approach based on the combination of high-performance liquid chromatography (HPLC) with (78)Se-specific selenium detection by inductively coupled plasma mass spectrometry (ICP MS) and high-resolution (100 000), high mass accuracy (<1 ppm) molecule-specific detection by electrospray-Orbitrap MS(3) was developed. For the first time, a non-aqueous mobile phase gradient was used in reversed-phase HPLC-ICP MS for the separation of a complex mixture of selenospecies and a mathematical correction of the background signal was developed.

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Phenyl-C61-butyric acid methyl ester (PCBM) is polymerized simply using a one-pot reaction to yield soluble, high molecular weight polymers. The sterically controlled azomethine ylide cycloaddition polymerization (SACAP) is demonstrated to be highly adaptable and yields polymers with probable Mn≈ 24 600 g mol(-1) and Mw≈ 73 800 g mol(-1). Products are metal-free and of possible benefit to organic and hybrid photovoltaics and electronics as they form thin films from solution and have raised LUMOs.

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Amphiphilic derivatives of chitosan using microwave irradiation. Toward an eco-friendly process to chitosan derivatives.

Carbohydr Polym

February 2015

Universite de Pau et des Pays de l'Adour (UPPA), IPREM, UMR 5254 CNRS/UPPA, Helioparc Pau Pyrenees, 2 Avenue P. Angot, 64053 PAU cedex 09, France. Electronic address:

Conventional heating and microwave irradiation have been compared for the synthesis of chitosans grafted with alkyl chains. Reaction time (1-60 min), temperature (25 and 40 °C) and chitosan molar mass have been studied onto the yield of alkylation. The irradiation mode has been scrupulously controlled to highlight the effect of the use of microwaves.

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Design of Magnetic Gelatine/Silica Nanocomposites by Nanoemulsification: Encapsulation Growth of Iron Oxide Colloids.

Nanomaterials (Basel)

July 2014

Chimie de la Matière Condensée de Paris, UMR 7574, Université Pierre et Marie Curie, Bât F, 4 place Jussieu, and Collège de France, 11 place Marcelin Berthelot, Paris 75005, France.

The design of magnetic nanoparticles by incorporation of iron oxide colloids within gelatine/silica hybrid nanoparticles has been performed for the first time through a nanoemulsion route using the encapsulation of pre-formed magnetite nanocrystals and the precipitation of ferrous/ferric ions. The first method leads to bi-continuous hybrid nanocomposites containing a limited amount of well-dispersed magnetite colloids. In contrast, the second approach allows the formation of gelatine-silica core-shell nanostructures incorporating larger amounts of agglomerated iron oxide colloids.

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Asymmetrical flow field-flow fractionation analysis of water suspensions of polymer nanofibers synthesized via RAFT-mediated emulsion polymerization.

Anal Chim Acta

March 2014

Laboratoire de Chimie Analytique BioInorganique et Environnement, UMR IPREM 5254 UPPA/CNRS-Technopole Hélioparc, Université de Pau et des Pays de l'Adour (UPPA), Av. du Président Angot, 64053 Pau cedex, France. Electronic address:

The aim of this work is to present a method based on asymmetric flow-field-flow-fractionation coupled on-line to a static light scattering (AF4-UV-SLS) detector to characterize self-assembled nanofibers (NFs). The method developed herein allows the determination of both the length distribution of the NFs as well as the distribution in terms of aggregation number per unit length (Agg). Given the remaining synthetic challenges of better controlling the structural homogeneity and particle dimensions, the NF length and aggregation number per unit length are becoming essential for the improvement and control of their chemical processes and a better understanding of their properties.

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A comparative study of two composts as filter media for the removal of gaseous reduced sulfur compounds (RSCs) by biofiltration: application at industrial scale.

Waste Manag

January 2013

Université de Pau et des Pays de l'Adour (UPPA), Laboratoire de Thermique, Energétique et Procédés (LaTEP), Equipe Traitement des Effluents Gazeux Site de Tarbes, Département Génie des Procédés, Quartier Bastillac, 65000 Tarbes, France.

This work presents the use of two composts as filter media for the treatment by biofiltration of odors emitted during the aerobic composting of a mixture containing sewage sludge and yard waste. The chemical analysis of the waste gas showed that the malodorous compounds at trace level were the reduced sulfur compounds (RSCs) which were dimethyl sulfide (Me(2)S), methanethiol (MeSH) and hydrogen sulfide (H(2)S). Laboratory tests for biofiltration treatment of RSCs were performed in order to compare the properties of two filter media, consisted of a mature compost with yard waste (YW) and a mixture of mature compost with sewage sludge and yard waste (SS/YW).

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Multi-wall carbon nanotube aqueous dispersion monitoring by using A4F-UV-MALS.

Anal Bioanal Chem

December 2011

Laboratoire de Chimie Analytique BioInorganique et Environnement, UMR IPREM 5254 UPPA/CNRS-Technopôle Hélioparc, Université de Pau et des Pays de l'Adour (UPPA), Pau cedex, France.

In this work, the potentiality of asymmetrical flow field-flow fractionation (A4F) hyphenated to UV detector and multi-angle light scattering (MALS) was investigated for accurately determining multi-walled carbon nanotube (MWCNT) length and its corresponding dispersion state in aqueous medium. Fractionation key parameters were studied to obtain a method robust enough for heterogeneous sample characterization. The main A4F conditions were 10(-5) mL min(-1) NH(4)NO(3), elution flow of 1 mL min(-1), and cross flow of 2 mL min(-1).

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In this work, the analytical potential of cyclical electrical field flow fractionation (CyElFFF) for nanomaterial and colloidal particle characterization has been experimentally demonstrated. Different operating parameters were investigated in order to evaluate their effect on the mechanisms of retention and fractionation power of CyElFFF. The voltage and frequency of the oscillating electrical field appeared to be the most influential parameters controlling the separation mode.

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Generation of a mesoporous silica MSU shell onto solid core silica nanoparticles using a simple two-step sol-gel process.

Chem Commun (Camb)

July 2011

Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux (IPREM), UMR 5254 CNRS, Equipe de Chimie Physique (ECP), Université de Pau et des Pays de l'Adour (UPPA), Technopôle Hélioparc Pau Pyrénées, 64053 PAU Cedex 09, France.

Silica core-shell nanoparticles with a MSU shell have been synthesized using several non-ionic poly(ethylene oxide) based surfactants via a two step sol-gel method. The materials exhibit a typical worm-hole pore structure and tunable pore diameters between 2.4 nm and 5.

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Asymmetrical flow field-flow fractionation (AFlFFF) hyphenated to multi-angle laser-light scattering (MALS) was evaluated in order to determine single walled carbon nanotube (SWCNT) length distribution. Fractionation conditions were investigated by examining mobile phase ionic strength and pH, channel components and cross-flow rate. Ammonium nitrate-based mobile phase with 10(-5)molL(-1) ionic strength and pH 6 allows the highest sample recovery (89±3%) to be obtained and the lowest loss of the longest SWCNT.

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