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3.
Sensors (Basel) ; 23(2)2023 Jan 10.
Article de Anglais | MEDLINE | ID: mdl-36679572

RÉSUMÉ

Actually, the quality of water is one of the most important indicators of the human environmental impact, the control of which is crucial to avoiding irreversible damage in the future. Nowadays, in parallel to the growth of the chemical industry, new chemical compounds have been developed, such as dyes and medicines. The increasing use of these products has led to the appearance of recalcitrant pollutants in industrial wastewater, and even in the drinking water circuit of our populations. The current work presents a photoreactor prototype that allows the performance of experiments for the decomposition of coloured pollutants using photocatalysis at the laboratory scale. The design of this device included the study of the photometric technique for light emission and the development of a software that allows monitoring the dye degradation process. Open-source hardware platforms, such as Arduino, were used for the monitoring system, which have the advantages of being low-cost platforms. A software application that manages the communication of the reactor with the computer and graphically displays the data read by the sensor was also developed. The results obtained demonstrated that this device can accelerate the photodegradation reaction in addition to monitoring the changes throughout the process.


Sujet(s)
Polluants environnementaux , Polluants chimiques de l'eau , Humains , Eaux usées , Polluants chimiques de l'eau/composition chimique
4.
Materials (Basel) ; 14(10)2021 May 11.
Article de Anglais | MEDLINE | ID: mdl-34064575

RÉSUMÉ

Whey in large quantities can cause environmental problems when discarded, because it reduces dissolved oxygen and aquatic life. Nonetheless, it could be used as an easily available and economical alternative to reduce culture medium costs in microbially induced calcium carbonate precipitation (MICP). In this work, a native Sporosarcina pasteurii was isolated and then cultured by using different proportions of whey (W) in nutrient broth (NB). The solids were characterized by XRD, FT-IR, TGA, and SEM. The potential applications in bioconsolidation were also studied. Whey concentration was directly related to CaCO3 production. Higher whey concentrations reduced calcium carbonate purity to nearly 80%. All experiments showed calcite and vaterite fractions, where a whey increment in the media increased calcite content and decreased vaterite content, causing a decrease in crystal size. MICP improved compressive strength (CS) in sand and fly ash. The best CS results were obtained by fly ash treated with 25 W-75 NB (37.2 kPa) and sand with 75 W-25 NB (32.1 kPa). Whey changed crystal polymorphism in biogenic CaCO3 production. Material bioconsolidation depends on the CaCO3 polymorph, thus fly ash was effectively bioconsolidated by crystallization of vaterite and sand by crystallization of calcite.

5.
BMJ Open ; 10(11): e039951, 2020 11 14.
Article de Anglais | MEDLINE | ID: mdl-33191263

RÉSUMÉ

INTRODUCTION: About 25% of patients with COVID-19 develop acute respiratory distress syndrome (ARDS) associated with a high release of pro-inflammatory cytokines such as interleukin-6 (IL-6). The aim of the SARICOR study is to demonstrate that early administration of sarilumab (an IL-6 receptor inhibitor) in hospitalised patients with COVID-19, pulmonary infiltrates and a high IL-6 or D-dimer serum level could reduce the progression of ARDS requiring high-flow nasal oxygen or mechanical ventilation (non-invasive or invasive). METHODS AND ANALYSIS: Phase II, open-label, randomised, multicentre, controlled clinical trial to study the efficacy and safety of the administration of two doses of sarilumab (200 and 400 mg) plus best available therapy (BAT) in hospitalised adults with COVID-19 presenting cytokine release syndrome. This strategy will be compared with a BAT control group. The efficacy and safety will be monitored up to 28 days postadministration. A total of 120 patients will be recruited (40 patients in each arm). ETHICS AND DISSEMINATION: The clinical trial has been approved by the Research Ethics Committee of the coordinating centre and authorised by the Spanish Agency of Medicines and Medical Products. If the hypothesis is verified, the dissemination of the results could change clinical practice by increasing early administration of sarilumab in adult patients with COVID-19 presenting cytokine release syndrome, thus reducing intensive care unit admissions. TRIAL REGISTRATION NUMBER: NCT04357860.


Sujet(s)
Anticorps monoclonaux humanisés/usage thérapeutique , Infections à coronavirus/traitement médicamenteux , Syndrome de libération de cytokines/traitement médicamenteux , Pneumopathie virale/traitement médicamenteux , /traitement médicamenteux , Adolescent , Adulte , Sujet âgé , Betacoronavirus , COVID-19 , Essais cliniques de phase II comme sujet , Infections à coronavirus/immunologie , Syndrome de libération de cytokines/immunologie , Femelle , Produits de dégradation de la fibrine et du fibrinogène/métabolisme , Humains , Interleukine-6/immunologie , Mâle , Adulte d'âge moyen , Études multicentriques comme sujet , Pandémies , Pneumopathie virale/immunologie , Essais contrôlés randomisés comme sujet , Ventilation artificielle , /immunologie , SARS-CoV-2 , Jeune adulte , Traitements médicamenteux de la COVID-19
6.
Molecules ; 25(12)2020 Jun 18.
Article de Anglais | MEDLINE | ID: mdl-32570887

RÉSUMÉ

Currently, valorization of lignocellulosic biomass almost exclusively focuses on the production of pulp, paper, and bioethanol from its holocellulose constituent, while the remaining lignin part that comprises the highest carbon content, is burned and treated as waste. Lignin has a complex structure built up from propylphenolic subunits; therefore, its valorization to value-added products (aromatics, phenolics, biogasoline, etc.) is highly desirable. However, during the pulping processes, the original structure of native lignin changes to technical lignin. Due to this extensive structural modification, involving the cleavage of the ß-O-4 moieties and the formation of recalcitrant C-C bonds, its catalytic depolymerization requires harsh reaction conditions. In order to apply mild conditions and to gain fewer and uniform products, a new strategy has emerged in the past few years, named 'lignin-first' or 'reductive catalytic fractionation' (RCF). This signifies lignin disassembly prior to carbohydrate valorization. The aim of the present work is to follow historically, year-by-year, the development of 'lignin-first' approach. A compact summary of reached achievements, future perspectives and remaining challenges is also given at the end of the review.


Sujet(s)
Fractionnement chimique , Lignine/composition chimique , Catalyse
7.
Materials (Basel) ; 13(5)2020 Mar 02.
Article de Anglais | MEDLINE | ID: mdl-32121622

RÉSUMÉ

The preparation of novel organic-inorganic hybrid mesoporous organosilica containing pyridinedicarboxamide functional groups uniformly distributed inside the nanostructured pore walls has been addressed. The mesoporosity and uniformity of the synthesized nanomaterials were characterized by different techniques such as nitrogen adsorption/desorption measurements and powder X-ray diffraction (PXRD). Additionally, the presence of the pyridinedicarboxamide in the pore walls of the nanomaterials was assessed by Fourier-transform infrared spectroscopy (FT-IR), as well as 29Si and 13C solid-state cross-polarization and magic angle spinning nuclear magnetic resonance (CP/MAS-NMR). The Knoevenagel condensation of aldehydes with active methylene compounds was carried out over the pyridinedicarboxamide functionalized mesoporous organosilica, which has been proven to be an efficient heterogeneous basic catalyst in the presence of ethanol as solvent. The catalytic activity of the investigated materials was investigated in the Knoevenagel condensation between malononitrile and several benzaldehyde derivatives exhibiting a high conversion (>90%) and excellent selectivity toward the final condensation products under very mild reaction conditions. Furthermore, the catalyst stability is noteworthy as it could be recycled and reused at least twelve times without any significant change in the performance.

8.
Front Chem ; 8: 42, 2020.
Article de Anglais | MEDLINE | ID: mdl-32083059

RÉSUMÉ

The acidity of Al-SBA-15 materials functionalized by ball milling with several niobium loadings (0. 25-1 wt.%) as well as with several fluorine loadings (by wet impregnation using NH4F as a precursor) was characterized and materials investigated in the esterification of valeric acid to alkyl valerates. The parent Al-SBA-15 support as well as the modified materials loaded with Nb and/or F have been catalysts synthesized characterized by X-ray diffraction (XRD), N2 physisorption measurements, and diffuse reflection infrared spectroscopy (DRIFT) among others. A special interest was paid on the acidity of the materials that was investigated by temperature-programmed desorption of pyridine. Interestingly, the characterization results for the materials containing fluorine showed up an increase in the acidity strength despite of a reduction in the number of acid sites. The catalytic performance of the as-prepared catalysts was investigated in the microwave-assisted esterification reaction of valeric acid to valerate esters. Thus, while the materials modified with niobium exhibited a lower catalytic activity as compared with the catalytic support (Al-SBA-15), the materials loaded with fluorine either onto Al-SBA-15 or on Nb1%/Al-SBA-15 materials presented enhanced conversion values of valeric acid. Therefore, it can be said that the new acid sites with enhanced strength formed by the incorporation of fluorine boost the esterification of valeric acid with alcohols to form the respective valerate ester.

9.
Rev. iberoam. psicol. (En línea) ; 13(3): 109-118, 2020.
Article de Espagnol | LILACS, COLNAL | ID: biblio-1224677

RÉSUMÉ

La sensibilidad se refiere a la capacidad del cuidador para percibir las señales del niño, interpretarlas correctamente y responder a ellas de manera contingente y apropiada. El Q Set del Comportamiento Materno (MBQS) fue creado a partir de descripciones teóricas y empíricas de la sensibilidad. Los Q-sorts se asocian con la metodología cuantitativa debido a que asignan puntajes; además, combinan la metodología cualitativa al hacer un estudio sistemático de la subjetividad. Son pocos los artículos que se ocupan de explorar el análisis, la validez interna, la confiabilidad o la replicabilidad externa de los Q-sorts. Usualmente los datos se reducen por medio de un análisis de componentes principales o análisis factorial. Sin embargo, en los Q-sorts se correlacionan los participantes para dilucidar las relaciones entre ellos en lugar de correlacionar las variables. El objetivo de la presente investigación fue encontrar evidencia respecto a la validez basada en la estructura interna del MBQS con el apoyo del software R y el paquete qmethod. Colaboraron 37 díadas mexicanas mamá-bebés, 35 colombianas y 24 uruguayas. En el 2002, Posada y colaboradores propusieron siete escalas. Las escalas en las que nuestro modelo factorial presentó un buen ajuste son las que tienen menos ítems, lo cual puede ser indicativo de que la falta de ajuste tiene que ver con la identificación del modelo debido a que se cuenta con pocas observaciones. Consideramos que tanto el uso del MBQS para evaluar la sensibilidad como del paquete qmethod para realizar el análisis resulta novedoso, relevante y pertinente


Sensitivity refers to the caregiver's ability to perceive infant's cues, interpret them correctly, and respond to them in a contingent and appropriate way. The Maternal Behavior Q Set (MBQS) was created from theoretical and empirical descriptions of sensitivity. Q-methodology is associated with the quantitative methodology because it assigns scores; in addition, it combines qualitative methodology by making a systematic study of subjectivity. Few papers are concerned with exploring the analysis, internal validity, reliability, or external replicability of Q studies. Usually analyses reduce data to a few summarizing factors, based on principal component analysis or centroid factor analysis. Q-factor analysis method was developed especially for q-sorted data; it is a by-person factor analysis which is used to identify groups of participants who make sense of a pool of items in comparable way. The aim of this study was to find evidence regarding the validity based on the internal structure of the MBQS using the R software and the qmethod package. Thirty-seven Mexican, 35 Colombian and 24 Uruguayan mother-baby dyads collaborated. In 2002, Posada et al. proposed seven scales. The scales in which our factorial model presented a good fit are those with the fewest items, which may be indicative that the lack of fit has to do with the identification of the model because there are few observations. We consider that both the use of the MBQS to assess sensitivity and the qmethod package to perform the analysis is novel, relevant and pertinent.


Sujet(s)
Humains , Aidants , Comportement maternel , Aptitude , Uruguay , Comportement , Sensibilité et spécificité , Colombie , Signaux , Mexique , Mères
10.
Molecules ; 24(21)2019 Nov 04.
Article de Anglais | MEDLINE | ID: mdl-31690007

RÉSUMÉ

In this study, the co-synthesis of TiO2 and Cu metallic nanoparticles obtained via one-pot cost-efficient hydrothermal process has been addressed. Different nanocatalysts with Cu contents were characterized by X-ray diffraction, nitrogen porosimetry, scanning electron microscopy, and transmission electron microscopy. The TiO2 and Cu metallic nanoparticles were synthesized with copper loading up to one (Cu/Ti atomic ratio). Synthesized catalysts exhibited pore sizes in the mesoporous range and high surface areas above 150 m2/g. The particle size for TiO2 presented a homogeneous distribution of approximately 8 nm, moreover, Cu nanoparticles varied from 12 to >100 nm depending on the metal loading. The nanostructured materials were successfully tested in the conversion of trans-ferulic acid into vanillin under sustainable conditions, achieving the best performance for 0.3 Cu/Ti atomic ratio (70% vanillin yield).


Sujet(s)
Benzaldéhydes/composition chimique , Cuivre/composition chimique , Acides coumariques/composition chimique , Nanoparticules/composition chimique , Titane/composition chimique , Catalyse
11.
BMJ Open ; 9(8): e030648, 2019 08 15.
Article de Anglais | MEDLINE | ID: mdl-31420397

RÉSUMÉ

INTRODUCTION: Prolonged use of antivirals to prevent the development of cytomegalovirus (CMV) disease in lung transplant patients has been shown to have significant side effects, for which alternatives are being sought to reduce their use. The monitoring of cell immunity against CMV could be an alternative as it has shown to be useful in identifying transplant patients at low risk of infection, who could benefit from shorter prophylaxis. The aim of the CYTOCOR study is to demonstrate that the combination of a reduced prophylaxis strategy with subsequent CMV-specific immunological monitoring would allow CMV infection to be controlled in lung transplant patients as effectively as the usual strategy (prophylaxis followed by pre-emptive therapy), while reducing the side effects of antivirals due to the shorter duration of prophylaxis. METHODS AND ANALYSIS: Phase III randomised, open, multicentre, parallel, non-inferiority clinical trial to study the efficacy and safety of the combination of a prophylaxis strategy up to month +3 post-transplant followed by immuno-guided prophylaxis using the QuantiFERON-CMV technique up to month +12 post-transplant to prevent CMV disease in CMV-seropositive lung transplant recipients. This strategy will be compared with a combination of a usual prophylaxis strategy up to month +6 post-transplant followed by pre-emptive therapy up to month +12. To study the incidence of CMV disease, patients will be followed up to 18 months post-transplantation. A total of 150 patients are expected to be recruited for the study. ETHICS AND PUBLIC DISSEMINATION: The clinical trial has been approved by the Research Ethics Committees and authorised by the Spanish Agency of Medicines and Medical Devices (AEMPS).If the hypothesis of this clinical trial is verified, the dissemination of the results could change clinical practice by increasing knowledge about the safety and efficacy of discontinuing valganciclovir prophylaxis in lung transplant recipients. TRIAL REGISTRATION NUMBER: NCT03699254.


Sujet(s)
Antiviraux/administration et posologie , Infections à cytomégalovirus/prévention et contrôle , Transplantation pulmonaire , Complications postopératoires/prévention et contrôle , Prémédication , Essais contrôlés randomisés comme sujet/méthodes , Antiviraux/effets indésirables , Essais cliniques de phase III comme sujet , Association thérapeutique , Cytomegalovirus/immunologie , Infections à cytomégalovirus/immunologie , Essais d'équivalence comme sujet , Humains , Immunité cellulaire , Études multicentriques comme sujet , Facteurs temps , Résultat thérapeutique
12.
Reumatol. clín. (Barc.) ; 13(6): 354-356, nov.-dic. 2017. ilus
Article de Espagnol | IBECS | ID: ibc-167212

RÉSUMÉ

Los pacientes con artritis reumatoide (AR) tratados con fármacos modificadores del curso de la enfermedad están expuestos a desarrollar infecciones potencialmente graves como la leishmaniasis. L. infantum es endémica en el Mediterráneo, hecho que obliga ante un paciente con AR que presenta fiebre y pancitopenia, a descartar este proceso. Un diagnóstico de sospecha precoz, puede evitar un curso y pronóstico fatal (AU)


Patients with rheumatoid arthritis (RA) treated with disease-modifying antirheumatic drugs are susceptible to severe infections such as leishmaniasis. As L. infantum is endemic in the Mediterranean region, it is necessary to rule this infectious process out in any RA patient presenting with fever and pancytopenia. An early diagnosis based on a high suspicion can prevent a fatal outcome (AU)


Sujet(s)
Humains , Femelle , Adulte d'âge moyen , Leishmaniose viscérale/complications , Polyarthrite rhumatoïde/traitement médicamenteux , Méthotrexate/usage thérapeutique , Hydroxychloroquine/administration et posologie , Glucocorticoïdes/administration et posologie , Amphotéricine B/administration et posologie , Pronostic , Comorbidité , Diagnostic différentiel , Diagnostic précoce
14.
Appl Petrochem Res ; 6(3): 243-256, 2016.
Article de Anglais | MEDLINE | ID: mdl-32355588

RÉSUMÉ

Biomass offers a unique resource for the sustainable production of bio-derived chemical and fuels as drop-in replacements for the current fossil fuel products. Lignin represents a major component of lignocellulosic biomass, but is particularly recalcitrant for valorization by existing chemical technologies due to its complex cross-linking polymeric network. Here, we highlight a range of catalytic approaches to lignin depolymerisation for the production of aromatic bio-oil and monomeric oxygenates.

15.
Phys Rev Lett ; 113(9): 092001, 2014 Aug 29.
Article de Anglais | MEDLINE | ID: mdl-25215978

RÉSUMÉ

We determine the nonperturbative gluon condensate of four-dimensional SU(3) gauge theory in a model-independent way. This is achieved by carefully subtracting high-order perturbation theory results from nonperturbative lattice QCD determinations of the average plaquette. No indications of dimension-two condensates are found. The value of the gluon condensate turns out to be of a similar size as the intrinsic ambiguity inherent to its definition. We also determine the binding energy of a B meson in the heavy quark mass limit.

16.
ChemSusChem ; 7(7): 1876-80, 2014 Jul.
Article de Anglais | MEDLINE | ID: mdl-24777936

RÉSUMÉ

A simple, environmentally friendly, and highly reproducible protocol has been developed for the mechanochemical preparation of advanced nanocatalytic materials in a one-pot process. The materials proved to have unprecedented activities in aqueous Suzuki couplings at room temperature, paving the way for a new generation of highly active and stable advanced nanocatalysts.


Sujet(s)
Composés du fer III/composition chimique , Phénomènes mécaniques , Nanocomposites/composition chimique , Silice/composition chimique , Température , Eau/composition chimique , Catalyse , Techniques de chimie synthétique
17.
Phys Chem Chem Phys ; 15(29): 12165-72, 2013 Aug 07.
Article de Anglais | MEDLINE | ID: mdl-23703022

RÉSUMÉ

Cu nanoparticles have been supported by two types of aluminosilicate materials with and without Zn in their composition in view of their application in the microwave-assisted conversion of glucose to valuable products via tandem formic acid-promoted dehydration (to 5-hydroxymethylfurfural--HMF) and further selective hydrogenation to 5-methylfurfuryl alcohol (MFA). Results show that interesting selectivities (up to 60% to MFA or HMF) could be achieved after short times of reaction (typically 2-30 min) using Cu-containing nanomaterials. Zn was found to play an interesting role in the selectivity to reduced products, even if present in very small quantities (0.2 wt%).


Sujet(s)
Cuivre/composition chimique , Glucose/composition chimique , Catalyse , Furfural/analogues et dérivés , Furfural/composition chimique , Furanes/composition chimique , Hydrogénation , Nanoparticules métalliques/composition chimique , Micro-ondes , Zinc/composition chimique
18.
ChemSusChem ; 6(3): 529-36, 2013 Mar.
Article de Anglais | MEDLINE | ID: mdl-23404837

RÉSUMÉ

Lignin valorization practices have attracted a great deal of interest in recent years due to the large excess of lignin produced by the pulp and paper industry, together with second-generation bioethanol plants. In this work, a new lignin valorization approach is proposed. It involves ultrafiltration as a fractionation process to separate different molecular weight lignin fractions followed by a hydrogen-free, mild, hydrogenolytic, heterogeneously catalyzed methodology assisted by microwave irradiation to obtain simple phenolic, monomeric products by depolymerization using a nickel-based catalyst. The main products obtained were desaspidinol, syringaldehyde, and syringol; this proves the efficiency of the depolymerization conditions applied. The concentration of these observed compounds increased when the molecular weights of the lignin fractions increased. The applied depolymerization conditions, which take advantage of the use of formic acid as a hydrogen-donating solvent, did not generate any biochar in the systems.


Sujet(s)
Lignine/composition chimique , Olea/composition chimique , Phénols/composition chimique , Solvants/composition chimique , Biocarburants , Papier , Polymérisation
19.
Carbohydr Polym ; 92(2): 1555-60, 2013 Feb 15.
Article de Anglais | MEDLINE | ID: mdl-23399188

RÉSUMÉ

Porous agar materials have been prepared from marine macroalgae species using a simple microwave-assisted extraction/drying methodology, providing a new family of polysaccharide derived porous solids. The microwave-assisted extraction allows a more efficient and less time-consuming extraction of the polysaccharide compared to conventional extraction protocols based on conventional heating. DRIFT and (13)C NMR results indicated that the internal agar structure (based on d-galactose and 3,6-anhydro-l-galactose linked units) was preserved after the extraction methodology, which opens a wide range of future possibilities and applications for this new family of porous polysaccharides. The extracted agar materials, which have already applications per se due to their high purities, could be subsequently transformed into a novel family of attractive mesoporous agar materials that could be used as natural templates for the production of nanocrystals of metal oxides.


Sujet(s)
Agar-agar/composition chimique , Produits biologiques/composition chimique , Gracilaria/composition chimique , Algue marine/composition chimique , Agar-agar/isolement et purification , Produits biologiques/isolement et purification , Porosité
20.
Materials (Basel) ; 6(5): 1891-1902, 2013 May 10.
Article de Anglais | MEDLINE | ID: mdl-28809249

RÉSUMÉ

Metal-containing mesoporous starches have been synthesized using a simple and efficient microwave-assisted methodology followed by metal impregnation in the porous gel network. Final materials exhibited surface areas >60 m² g-1, being essentially mesoporous with pore sizes in the 10-15 nm range with some developed inter-particular mesoporosity. These materials characterized by several techniques including XRD, SEM, TG/DTA and DRIFTs may find promising catalytic applications due to the presence of (hydr)oxides in their composition.

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