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Partial substitution of V by other transition metals in Na3 V2 (PO4 )3 (NVP) can improve the electrochemical performance of NVP as a cathode for sodium-ion batteries (SIBs). Herein, phosphate Na-V-Mn-Ni-containing composites based on NASICON (Natrium Super Ionic Conductor)-type structure have been fabricated by sol-gel method. The synchrotron-based X-ray study, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) studies show that manganese/nickel combinations successfully substitute the vanadium in its site within certain limits. Among the received samples, composite based on Na3.83 V1.17 Mn0.58 Ni0.25 (PO4 )3 (VMN-0.5, 108.1 mAh g-1 at 0.2 C) shows the highest electrochemical ability. The cyclic voltammetry, galvanostatic intermittent titration technique, in situ XRD, ex situ XPS, and bond valence site energy calculations exhibit the kinetic properties and the sodium storage mechanism of VMN-0.5. Moreover, VMN-0.5 electrode also exhibits excellent electrochemical performance in quasi-solid-state sodium metal batteries with PVDF-HFP quasi-solid electrolyte membranes. The presented work analyzes the advantages of VMN-0.5 and the nature of the substituted metal in relation to the electrochemical properties of the NASICON-type structure, which will facilitate further commercialization of SIBs.
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Current approaches for the assessment of environmental and human health risks due to exposure to chemical substances have served their purpose reasonably well. Nevertheless, the systems in place for different uses of chemicals are faced with various challenges, ranging from a growing number of chemicals to changes in the types of chemicals and materials produced. This has triggered global awareness of the need for a paradigm shift, which in turn has led to the publication of new concepts for chemical risk assessment and explorations of how to translate these concepts into pragmatic approaches. As a result, next-generation risk assessment (NGRA) is generally seen as the way forward. However, incorporating new scientific insights and innovative approaches into hazard and exposure assessments in such a way that regulatory needs are adequately met has appeared to be challenging. The European Partnership for the Assessment of Risks from Chemicals (PARC) has been designed to address various challenges associated with innovating chemical risk assessment. Its overall goal is to consolidate and strengthen the European research and innovation capacity for chemical risk assessment to protect human health and the environment. With around 200 participating organisations from all over Europe, including three European agencies, and a total budget of over 400 million euro, PARC is one of the largest projects of its kind. It has a duration of seven years and is coordinated by ANSES, the French Agency for Food, Environmental and Occupational Health & Safety.
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Medición de Riesgo , Humanos , Europa (Continente)RESUMEN
OBJECTIVES: Between 2015 and 2019, 5700 excess deaths were observed during heatwaves in France. The summer of 2020 combined exceptionally high temperatures with the COVID-19 pandemic. The associated health impacts of this unique situation are described in this study. STUDY DESIGN: This is an observational study based on indicators of the French heat prevention plan. METHODS: Mortality and morbidity data during heatwaves were compared between 2020 and previous years, alongside COVID-19 in-hospital mortality. RESULTS: In total, 1921 additional deaths (+18.2%) were observed during the 2020 heatwaves, which is the largest number of deaths observed since 2003. Less than 100 deaths were attributed to COVID-19 during the heatwaves of 2020. CONCLUSIONS: Exceptionally high temperatures driven by climate change, combined with health inequities exacerbated by the COVID-19 outbreak, may have increased vulnerability to heat in 2020.
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COVID-19/mortalidad , Cambio Climático , Calor , Rayos Infrarrojos , Anciano , Brotes de Enfermedades , Francia/epidemiología , Disparidades en Atención de Salud , Mortalidad Hospitalaria , Humanos , Persona de Mediana Edad , Morbilidad , Pandemias , SARS-CoV-2 , Estaciones del AñoRESUMEN
Speech-in-noise testing as a marker for noise-induced hearing loss and tinnitus. Noise-induced hearing loss and tinnitus are auditory complaints that often co-occur. Often, there is no immediate indication of changes in the pure tone audiogram. Patients can still have clinically normal hearing thresholds while clearly experiencing reduced speech comprehension. This might be explained by the process of neurodegeneration of the innervated dendrites of the auditory nerve fibres and secondary degeneration of spiral ganglion neurons. Subsequent maladaptive neuronal plasticity of the central auditory system can induce tinnitus. Standard hearing testing is no longer sufficient in these patients. Therefore more complex tasks, such as speech-in-noise tests, might be valuable extensions to the standard hearing tests. We carried out a prospective investigation of the influence of tinnitus upon speech comprehension in noise and the effectiveness of speech-in-noise testing, using the Flemish version of the digit triplet test (DTT). Thirty-seven patients with mild noise-induced hearing loss, tinnitus complaints and clinically normal pure tone thresholds completed the DTT and filled in two tinnitus enquiries. A statistically significant (p=0.026) correlation between the averaged high PTA, 2,z and the averaged SRT across ears on the DTT was found. There also seems to be a slight influence of tinnitus onset on the SRT score.
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Pérdida Auditiva Provocada por Ruido/diagnóstico , Ruido , Percepción del Habla , Acúfeno/diagnóstico , Adolescente , Adulto , Audiometría de Tonos Puros , Audiometría del Habla , Pérdida Auditiva Provocada por Ruido/fisiopatología , Humanos , Estudios Prospectivos , Acúfeno/fisiopatología , Adulto JovenRESUMEN
AUTOMATED IMPEDANCE MANOMETRY (AIM): OBJECTIVE DIAGNOSIS OF OROPHARYNGEAL DYSPHAGIA: This review article aims to demonstrate the clinical potential of Automated Impedance Manometry (AIM) as a new, non-radiological technique for screening and diagnosis of oro-pharyngeal dysphagia. An integrated - rather than separate - analysis of pressure and impedance patterns generated in the pharynx when swallowing a food bolus, can be a useful complement to the radiological investigations considered as gold standard today. Major advantages are the objective nature of this technique and the fully automated calculation of various swallow parameters. A global measure of swallowing function can be derived (a Swallow Risk Index, SRI) and is related to (the severity of) the risk of aspiration and the presence of pharyngeal post-swallow residue. It was shown that aspiration on videofluoroscopy was accurately detected by using AIM with a sensitivity of 0.88 and a specificity of 0.96. AIM analysis can be performed quickly and is reliable in the hands of different end users. Various parameters are sufficiently sensitive to detect changes in bolus consistency and - as was recently found - are influenced by swallowing manoeuvers. Furthermore, different patterns of deviant swallow parameters can be found in different patient populations. Whether this observation can provide specific diagnoses and - as a consequence - more targeted treatments is currently under investigation.
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Photocatalytic water disinfection has emerged as a promising approach for water purification. However, exploring efficient and rapid visible light driven materials for photocatalytic bacterial inactivation is still a challenging problem. Herein, red phosphorus/titanium oxide (TiO2@RP) nanofibers were developed for effective water disinfection by a vacuum ampoule strategy. The complete E. coli and S. aureus (7-log CFU mL-1) could be rapidly killed within 25 min and 30 min over the optimized TiO2@RP heterostructure under the white LED irradiation. The efficient photocatalytic antibacterial activity should be mainly ascribed to the synergetic enhancement in light absorption by RP decoration and charge migration and separation by the interface between TiO2 and RP. And then more unpaired photo-carriers would be transferred to the surface to facilitate the generation of photo-holes, â¢O2- radicals, and H2O2 species, which could destroy the bacterial cells efficiently.
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Escherichia coli , Nanofibras , Catálisis , Peróxido de Hidrógeno , Luz , Fósforo , Staphylococcus aureus , TitanioRESUMEN
Polycrystalline potassium nickel(II) hafnium(IV) tris-(orthophosphate), a langbeinite-type phosphate, was synthesized by a solid-state method. The three-dimensional framework of the title compound is built up from two types of [MO6] octa-hedra [the M sites are occupied by Hf:Ni in ratios of 0.754â (8):0.246â (8) and 0.746â (8):0.254â (8), respectively] and [PO4] tetra-hedra are connected via O vertices. The K+ cations are located in two positions within large cavities of the framework, having coordination numbers of 9 and 12. The Hf, Ni and K sites lie on threefold rotation axes, while the P and O atoms are situated in general positions.
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There is wide interest in developing efficient, robust and low-cost electrode materials for the electrolysis of water to produce clean hydrogen fuel. It is especially important to improve the performance and durability of electrocatalysts for the OER. Here we have shown that the transformation of nanoparticle (n-NNP) and crystalline (c-NNP) forms of mixed phosphate Na4Ni3(PO4)2P2O7 in highly alkaline solutions occurs along various routes and provokes the generation of 2D Ni(OH)2 nanosheets or stable core(phosphate)-shell(Ni(OH)2) particles, respectively. In both cases, in the carbon matrix (through chemical and electrochemical conversion of phosphate in situ during electrolysis in a 6 M KOH or NaOH solution) stable OER electrocatalysts with low overpotentials of 250-290 mV at a current density of 10 mA cm-2 were obtained. The best candidate for the OER process is core-shell particles, which maintain overpotentials of around 250 mV in 6 M KOH for more than 3 days. The activity enhancement can be attributed to the formation of abundant NiOOH nanoparticles on the shell surface due to improved lattice matching. This report discusses future prospects for the creation of core-shell particles to reduce the overpotential of durable electrocatalysts for the OER.
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The evolution of high-performance and stable electrode materials for supercapacitors plays a vital role in the next generation of energy storage devices. In this work we present a simple method for preparing Bi(nanoparticles)/CNx(nanosheets) nanocomposites as electrode materials for supercapacitors, which were synthesized by thermally treating bismuth citrate and urea at 550-700 °C under an Ar atmosphere. According to physicochemical studies (XRD, SEM, TG-DTA, XPS, FTIR, and BET), a "smeared" bismuth formation or the formation of nanoparticles on the CNx surface of interwoven 2D-nanosheets at different calcination temperatures was observed. Electrochemical measurements show that the specific capacity of the composites can reach 1251 F g-1 (more than 90% of the theoretical value) at a current density of 500 mA g-1 in a 6 M KOH electrolyte, and most two-dimensional CNx-based nanostructures remain intact after multiple galvanostatic charge-discharge processes, which is promising for the development of highly efficient supercapacitors. A supercapacitor composed of Bi/CNx nanocomposites for the negative electrode and Ni-layered hydroxide for the positive electrode demonstrates a high energy density of 58 W h kg-1 with a power density of 800 W kg-1 accompanied by a good cycle life (the parameters decreased down to only 78% after 1000 charge-discharge cycles). Our current results indicate that the addition of urea not only determines the morphology of the composites, but also lays the foundation for the development of new types of nanocomposites for the power industry.
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The photoelectrochemical properties of scheelite-related MBi1-xV1-xMoxO4 (MII = Ca, Sr, x = 0.1 to 0.9) solid solutions deposited on conductive glass (coated with SnO2, F-doped) have been investigated as photoanodes in photoelectrochemical (PEC) water splitting. The variation of the final annealing temperature during the preparation of the conduction electrodes as well as the value of substitution x have been shown to affect the PEC performance. The micropowders of MBi1-xV1-xMoxO4 (MII = Ca, Sr, x = 0.1 to 0.9) samples were first fabricated vi a solid-state method; they were characterised by SEM microscopy and powder and single crystal X-ray diffraction, and the band gap values were estimated using diffusive reflectance data. The value of substitution x = 0.1 in the cases of samples containing calcium and strontium affords the highest PEC performance reported for the whole range of substitution. These results demonstrate a promising approach for the beneficial utilization of BiVO4-substituted scheelite-related solid solutions in photo-electrochemical cells towards efficient and inexpensive photoanodes.
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The aim of this study was to assess the influence of the polycyclic aromatic hydrocarbons (PAH)-degrading activity in the fate of fluoranthene in soils. Three soil samples with different degrading activities (an industrial soil, the same industrial soil after biostimulation, and an agricultural soil) were spiked with 14C-fluoranthene and incubated for 6 mo with monitoring of biodegradation and mineralization. To follow the distribution of the 14C-fluoranthene residues (i.e., 14C-fluoranthene and its degradation products) among the soil compartments, we performed successively leaching, centrifugation (to collect intra-aggregate pore water), solvent extraction, and combustion of the soil columns. In the industrial soil, no mineralization of 14C-fluoranthene was observed, and only 3% of the initial 14C-activity was non-extractable (with acetone:dichloromethane) after 165 d of incubation. The biostimulation (addition of unlabeled polycyclic aromatic hydrocarbons) increased the degrading activity in this soil (59% of 14C-fluoranthene was mineralized) and increased the residues sequestration (13% of 14C-activity was non-extractable). The microflora of the agricultural soil mineralized 14C-fluoranthene more slowly and to a lesser extent (25%) than the biostimulated soil, but a higher amount of 14C-activity was sequestered (41%). Thus, the rate and extent of 14C-fluoranthene mineralization seemed to be related to the 14C-activity sequestration by controlling the accumulation of degradation products in the soil. 14C-Fluoranthene biodegradation enhanced the concentration of 14C-polar compounds in the intra-aggregate pore water. Our results point out the close link between fluoranthene biodegradation and two key aging processes, diffusion and sequestration, in soils. Biodegradation controls the mobility and sequestration of residues by transforming fluoranthene into more polar molecules that can diffuse into the intra-aggregate pore water and then might become bound to the matrix or entrapped in the microporosity.
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Fluorenos/metabolismo , Contaminantes del Suelo/metabolismo , Suelo/análisis , Biodegradación Ambiental , Isótopos de Carbono , Fluorenos/análisis , Tamaño de la Partícula , Porosidad , Contaminantes del Suelo/análisis , Factores de TiempoRESUMEN
A numerical heat transfer model for predicting product temperature profiles during high-pressure thawing processes was recently proposed by the authors. In the present work, the predictive capacity of the model was considerably improved by taking into account the pressure dependence of the latent heat of the product that was used (Tylose). The effect of pressure on the latent heat of Tylose was experimentally determined by a series of freezing experiments conducted at different pressure levels. By combining a numerical heat transfer model for freezing processes with a least sum of squares optimization procedure, the corresponding latent heat at each pressure level was estimated, and the obtained pressure relation was incorporated in the original high-pressure thawing model. Excellent agreement with the experimental temperature profiles for both high-pressure freezing and thawing was observed.
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Modelos Químicos , Congelación , Calor , PresiónRESUMEN
A numerical model for predicting conductive heat transfer during batch high hydrostatic pressure (HHP) processing of foods was developed and tested for a food simulator (agar gel). For a comprehensive evaluation of the proposed method, both "conventional" HHP processes, HHP processes with gradual, step-by-step pressure buildup and pressure release, and pressure cycling HHP processes were included. In all cases, good agreement between experimental and predicted temperature profiles was observed. The model provides a very useful tool to evaluate batch HHP processes in terms of uniformity of any heat- and/or pressure-related effect. This is illustrated for inactivation of Bacillus subtilis alpha-amylase, an enzymatic model system with known pressure-temperature degradation kinetics.
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Manipulación de Alimentos/métodos , Modelos Teóricos , Agar , Bacillus subtilis/enzimología , Estudios de Evaluación como Asunto , Manipulación de Alimentos/instrumentación , Tecnología de Alimentos , Geles , Calor , Presión Hidrostática , Cinética , Desnaturalización Proteica , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/químicaRESUMEN
As a result of isotopic dilution, the availability to plants of radioisotopes introduced into the soil solution should be directly related to the size of the isotopically exchangeable pool (E(t))-value). This work was undertaken to test this hypothesis for the radionuclide 63Ni. The demonstration was based on pot experiments conducted with seven soils representing a large range of Ni content (from 9.9 mg kg(-1) to 862.6 mg kg(-1)) which were mixed with a 63NiCl2 solution (100 kBq kg(-1)). Three plant species varying in Ni uptake, Triticum aestivum (wheat), Trifolium pratense (clover), and the Ni-hyperaccumulator Alyssum murale, were grown for 90 d, and their total Ni and 63Ni content determined at harvest. In parallel, the isotopically exchangeable kinetics method (IEK) was run on each soil sample to measure the E(t)-value. Results showed that plant uptake of radioactive nickel was negatively correlated with the E(t)-value with wheat and clover as a result of the dilution of 63Ni added in the isotopically exchangeable pool of soil Ni (alpha=5%); correlation was positive with the A. murale (alpha=10%). Hence, this provides a new approach for the assessment of soil-to-plant transfer of 63Ni at larger scale avoiding the carrying out of time consuming experiments.
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Níquel/farmacocinética , Plantas/metabolismo , Radioisótopos/farmacocinética , Contaminantes Radiactivos del Suelo/farmacocinética , Brassicaceae/química , Brassicaceae/metabolismo , Humanos , Modelos Biológicos , Níquel/análisis , Plantas/química , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Trifolium/química , Trifolium/metabolismo , Triticum/química , Triticum/metabolismoRESUMEN
Leaves of plants have the ability to accumulate the long-lived fission product (99)Tc. In the present work, an attempt was made to separate and characterize technetium species formed in maize grown on soil contaminated with Tc(VII)O(4)(-) solution. Data obtained from selective extraction, a Phosphorimager and liquid scintillation were employed.
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Residuos Radiactivos , Contaminantes Radiactivos del Suelo/farmacocinética , Tecnecio/farmacocinética , Cromatografía , Fósforo/análisis , Tecnecio/química , Zea mays/químicaRESUMEN
Combined conductive and convective heat transfer during thermal pasteurisation of intact eggs was studied using a commercial Computational Fluid Dynamics (CFD) package. A kinetic inactivation model for Salmonella enteritidis was combined with the CFD model, enabling evaluation and assessment of egg pasteurisation processes. Simulated temperature profiles were found to be in good agreement with experimentally observed data. The obtained results offer a useful tool for assessment and optimisation of egg pasteurisation processes.