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1.
Front Chem ; 10: 977980, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186595

RESUMO

In many countries, the textile industry remains the major contributor to environmental pollution. Untreated textile dyes discharged into water negatively impact the performance of aquatic organisms and may cause a variety of serious problems to their predators. Effective wastewater treatment is a key to reducing environmental and human health risks. In this work, the Fe/Cu catalysts were used in heterogeneous Fenton's reaction for the degradation of high concentrations of methyl orange (model azo dye) in aqueous solutions. For the first time, the catalysts were prepared onto commercial copper foams by potentiostatic electrodeposition of iron using an environmentally friendly electrolyte. The influence of electrodeposition conditions, H2O2 concentration, dye concentration and temperature on the model dye degradation was investigated. It was revealed that both the surface area and the catalyst loading play the major role in the effective dye degradation. The experimental results involving spectrophotometric measurements coupled with total carbon and nitrogen quantification suggest that a solution containing up to 100 mg/L of methyl orange can be successfully decolorized within 90 s at 50°C using porous Fe/Cu catalyst in the presence of hydrogen peroxide that largely surpasses the current state-of-the-art performance. Already within the first 10°min, ∼ 30% of total methyl orange concentration is fully mineralized. The described process represents a cost-efficient and environmentally friendly way to treat azo dyes in aqueous solutions.

2.
Plant Dis ; 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36167516

RESUMO

Cork oak (Quercus suber L.) is an evergreen tree native to SW Europe and NW Africa. It covers 2·106 ha in the western Mediterranean basin, forms heterogeneous forest ecosystems and represents an important source of income derived from cork production. While in Iberia, Italy, Tunisia and Algeria, drought and several endemic pathogens have been associated with cork oak decline (Moricca et al. 2016; Smahi et al. 2017), in Morocco there is no evidence, apart from overgrazing and human intervention (Fennane and Rejdali 2015), of a pathogen associated with oak decline. In December 2019, extensive dieback and mortality of 60-year-old cork oak trees were observed in a natural stand of ca 150 ha located 5 km east from Touazithe, in Maâmora forest, Morocco (34°13'38''N, 6°14'51''W - 87 m a.s.l.). Two years before, Q. suber seedlings from a local nursery were planted to increase tree density. Symptoms in trees and planted seedlings included chlorosis, reddish-brown discoloration of the whole crown and dieback starting in the upper crown. Root rot and lack of fine roots were observed. Tree mortality was estimated at ca 30%, and disease incidences of trees and seedlings were 45 and 70%, respectively. A Phytophthora species was consistently isolated from the rhizosphere of 3 symptomatic trees randomly selected at the site using leaves as bait (Jung et al. 1996). On carrot agar Phytophthora colonies were uniform and cottonwool-like. Sporangia were typically terminal, with ovoid, and obpyriform shape, mostly papillate, measuring 30.7 ± 4.7 µm length and 22.7 ± 4.1 µm wide. Oogonia were produced in single culture, and they were globose to subglobose, elongated to ellipsoid, 32.1 ± 2.9 µm in diameter and 46.1 ± 4.8 µm in length. Oospores were usually spherical, thick-walled, and measured 28.1 ± 2.4 µm. Antheridia were paragynous, mostly spherical, measuring 12.2 ± 1.4 µm. Isolates had minimum and maximum temperatures of 5 °C and 30 °C, respectively, and a growth optimum at 20 °C. Apart from the small size of sporangia, features were typical of Phytophthora quercina Jung. The identity of a representative strain (TJ1500) was corroborated by sequencing the ITS and mitochondrial cox1 gene regions, and BLAST search in GenBank showed 100% homology with sequences of the ex-type culture of P. quercina (KF358229 and KF358241 accessions, respectively). Both sequences of the representative isolate were submitted to GenBank (accessions OP086243 and OP290549). The strain TJ1500 is currently stored within the culture collections of the Mendel University in Brno and the University of Sassari. Its pathogenicity was verified and compared with a P. cinnamomi strain in a soil infestation test with one-year-old cork oak seedlings (Corcobado et al. 2017). Five months after inoculation, the symptoms described were observed in the seedlings, and fine root weight of plants inoculated with the TJ1500 strain and P. cinnamomi was reduced by 19 and 42%, respectively, in relation to non-inoculated controls. The pathogen was re-isolated from the necrotic roots, thus fulfilling Koch's postulates. So far, P. quercina has been reported associated with chronic mortality of cork oak in new plantations in Spain (Martín-García et al. 2015; Jung et al. 2016) and natural forests in Italy (Seddaiu et al. 2020). To our knowledge this is the first report of P. quercina in Morocco. Givenat Morocco is an important cork producing country, our finding warns about the risk this pathogen poses to Q. suber and other North African oaks.

3.
Chem Rev ; 122(12): 10899-10969, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34529918

RESUMO

This is a critical review of artificial intelligence/machine learning (AI/ML) methods applied to battery research. It aims at providing a comprehensive, authoritative, and critical, yet easily understandable, review of general interest to the battery community. It addresses the concepts, approaches, tools, outcomes, and challenges of using AI/ML as an accelerator for the design and optimization of the next generation of batteries─a current hot topic. It intends to create both accessibility of these tools to the chemistry and electrochemical energy sciences communities and completeness in terms of the different battery R&D aspects covered.


Assuntos
Inteligência Artificial , Aprendizado de Máquina
4.
PLoS One ; 16(11): e0259087, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34735472

RESUMO

Physical fitness is related to well-being and health. Adolescence is a key period in the psychological and social development of the person, in which interpersonal relationships gain strength, being bullying a type of violence that can affect the personality of those involved. At present, there is not enough research to determine the relationships between bullying and physical condition. The purpose of this study is to find out if there are any relationships among physical fitness, victimisation, and aggression in bullying, and to identify these behaviours. This is a descriptive study done in 1035 adolescents aged 12 to 17 years (M = 14.67, SD = 1.49). The European Bullying Intervention Project Questionnaire (EBIPQ) scale was used, and anthropometric characteristics of weight and height were measured. In addition, physical fitness tests from the Eurofit battery, sit-and-reach, 30-second sit-ups, horizontal jump, manual dynamometry, and 20-meter Multistage Shuttle Run Test (SRT) were included. The relationships between variables were analysed using Spearman correlations, linear regressions, and ordinal regressions. The most relevant findings indicate an inverse relationship between being a victim of bullying and having a better cardiorespiratory cardiovascular endurance. These also show a direct relationship between being a bully and skeletal muscle strength measured through the horizontal jump, 30-second sit-ups, and manual dynamometry tests. Theoretically, we can conclude that physical condition can be considered a predictor to consider in bullying. Specifically, cardiorespiratory fitness, in addition to its multiple physical and mental benefits, may be a protective element against bullying victimisation. In contrast, muscular strength, especially in boys, may be an important predictor, especially in the physical component, of aggression in bullying.


Assuntos
Agressão/psicologia , Bullying/psicologia , Vítimas de Crime/psicologia , Aptidão Física/psicologia , Adolescente , Agressão/fisiologia , Índice de Massa Corporal , Aptidão Cardiorrespiratória/fisiologia , Aptidão Cardiorrespiratória/psicologia , Criança , Feminino , Humanos , Masculino , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Aptidão Física/fisiologia
5.
Environ Sci Technol ; 54(7): 4664-4674, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32108464

RESUMO

Herein, the novel application of FeS2/C nanocomposite as a highly active, stable, and recyclable catalyst for heterogeneous electro-Fenton (EF) treatment of organic water pollutants is discussed. The simultaneous carbonization and sulfidation of an iron-based metal-organic framework (MOF) yielded well-dispersed pyrite FeS2 nanoparticles of ∼100 nm diameter linked to porous carbon. XPS analysis revealed the presence of doping N atoms. EF treatment with an IrO2/air-diffusion cell ensured the complete removal of the antidepressant fluoxetine spiked into urban wastewater at near-neutral pH after 60 min at 50 mA with 0.4 g L-1 catalyst as optimum dose. The clear enhancement of catalytic activity and stability of the material as compared to natural pyrite was evidenced, as deduced from its characterization before and after use. The final solutions contained <1.5 mg L-1 dissolved iron and became progressively acidified. Fluorescence excitation-emission spectroscopy with parallel factor analysis demonstrated the large mineralization of all wastewater components at 6 h, which was accompanied by a substantial decrease of toxicity. A mechanism with •OH as the dominant oxidant was proposed: FeS2 core-shell nanoparticles served as Fe2+ shuttles for homogeneous Fenton's reaction and provided active sites for the heterogeneous Fenton process, whereas nanoporous carbon allowed minimizing the mass transport limitations.


Assuntos
Estruturas Metalorgânicas , Poluentes Químicos da Água , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Oxirredução , Águas Residuárias
6.
Movimento (Porto Alegre) ; 26: e26091, 2020.
Artigo em Inglês | LILACS | ID: biblio-1154909

RESUMO

Bullying is a social problem characterized by intentional aggression over time, usually in school contexts and in cyberspace (cyberbullying). There has been growing interest in preventing that phenomenon to reduce its adverse effects. Different studies and reports suggest that Physical Education may be a setting of interest to promote attitudes and behaviors against bullying. This work examines the state of the debate in this area through scientific literature. Based on the analysis of the evidence, we conclude by making recommendations regarding strategies and skills that should be included in Physical Education curricula to prevent bullying and cyberbullying. Among those most widely used, we highlight cooperative methodologies, a teaching attitude that promotes a motivational climate focused on the task, and curricular integration of teaching resources that address skills and protective factors.


O bullying é um problema social caracterizado pela agressão intencional que ocorre ao longo do tempo, geralmente em contextos escolares e no ciberespaço (cyberbullying). Tem havido um interesse crescente na prevenção deste fenômeno, a fim de reduzir os efeitos adversos. Diferentes estudos e relatórios sugerem que o tema da Educação Física pode ser um cenário de interesse para promover atitudes e comportamentos contra o bullying. O objetivo deste trabalho é examinar o estado da questão nesta área através de uma revisão da literatura científica. Com base na análise das evidências, concluímos fazendo recomendações sobre estratégias e habilidades que devem ser incluídas nos currículos de Educação Física para prevenir o bullying e o cyberbullying. Dentre as mais utilizadas, destacamos as metodologias cooperativas, uma atitude de ensino que promove um clima motivacional focado na tarefa e a integração curricular de recursos didáticos que abordam habilidades e fatores de proteção.


El acoso escolar es un problema social caracterizado por la agresión intencional que se produce a lo largo del tiempo, generalmente en contextos escolares y en el ciberespacio (ciberacoso). Hay un creciente interés en la prevención de este fenómeno, con el fin de reducir sus efectos adversos. Diferentes estudios e informes sugieren que la Educación Física puede impulsar actitudes y comportamientos contra el acoso escolar. El objetivo de este trabajo es examinar, a través de una revisión de la literatura científica, el estado de este tema en el área. Con base en el análisis de las evidencias, concluimos con recomendaciones sobre estrategias y habilidades que deberían incluirse en los currículos de Educación Física para prevenir el acoso y el ciberacoso. Entre las más utilizadas, destacamos las metodologías cooperativas, una actitud docente que promueve un clima motivacional centrado en la tarea y la integración curricular de recursos didácticos que aborden habilidades y factores de protección.


Assuntos
Humanos , Masculino , Feminino , Educação Física e Treinamento , Problemas Sociais , Prevenção de Doenças , Bullying , Atividade Motora , Ensino , Comportamento , Agressão , Cyberbullying
7.
J Plant Physiol ; 241: 153030, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31493717

RESUMO

Phytophthora cinnamomi (Pc) is a dangerous pathogen that causes root rot (ink disease) and threatens the production of chestnuts worldwide. Despite all the advances recently reported at molecular and physiological level, there are still gaps of knowledge that would help to unveil the defence mechanisms behind plant-Pc interactions. Bearing this in mind we quantified constitutive and Pc-induced stress-related signals (hormones and metabolites) complemented with changes in photosynthetic related parameters by exploring susceptible and resistant Castanea spp.-Pc interactions. In a greenhouse experiment, five days before and nine days after inoculation with Pc, leaves and fine roots from susceptible C. sativa and resistant C. sativa × C. crenata clonal 2-year-old plantlets were sampled (clones Cs14 and 111-1, respectively). In the resistant clone, stomatal conductance (gs) and net photosynthesis (A) decreased significantly and soluble sugars in leaves increased, while in the susceptible clone gs and A remained unchanged and proline levels in leaves increased. In the resistant clone, higher constitutive content of root SA and foliar ABA, JA and JA-Ile as compared to the susceptible clone were observed. Total phenolics and condensed tannins were highest in roots of the susceptible clone. In response to infection, a dynamic hormonal response in the resistant clone was observed, consisting of accumulation of JA, JA-Ile and ABA in roots and depletion of total phenolics in leaves. However, in the susceptible clone only JA diminished in leaves and increased in roots. Constitutive and Pc-induced levels of JA-Ile were only detectable in the resistant clone. From the hormonal profiles obtained in leaves and roots before and after infection, it is concluded that the lack of effective hormonal changes in C. sativa explains the lack of defence responses to Pc of this susceptible species.


Assuntos
Resistência à Doença , Fagaceae/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Phytophthora , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Plantas/fisiologia , Resistência à Doença/fisiologia , Fagaceae/imunologia , Fagaceae/microbiologia , Metaboloma/fisiologia , Phytophthora/fisiologia , Doenças das Plantas/imunologia , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/fisiologia , Raízes de Plantas/fisiologia
8.
Eng. sanit. ambient ; 24(2): 295-304, mar.-abr. 2019. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1012026

RESUMO

RESUMO A presença das cianobactérias é uma das grandes preocupações para o tratamento de água, uma vez que esses microrganismos podem ser produtores de metabólitos tóxicos, como as microcistinas (MCs), que não são efetivamente removidas no tratamento usualmente empregado de ciclo completo. Para a remoção dessas toxinas, pode-se, de forma complementar, utilizar adsorvedores como o carvão ativado (CA), que apresenta eficiência variada, em função de suas características. Este trabalho teve como objetivo fornecer subsídios técnicos e científicos para a seleção de carvões ativados pulverizados (CAPs) e carvões ativados granulares (CAGs) como adsorvedores de MCs. Para tanto, foi realizado, primeiramente, um experimento de seleção de CAs com maior capacidade adsortiva para MCs, em escala de bancada. Em seguida, para os CAPs e CAGs selecionados, foi realizada caracterização complementar para a distribuição de volume específico em função do tamanho do poro. Posteriormente, foram elaboradas isotermas de adsorção de Freundlich e curvas de ruptura. Pôde-se constatar que, dentre os CAs amostrados, os importados apresentaram maior capacidade adsortiva para MCs do que os nacionais. Além disso, foi possível concluir que a escolha do CA pode ser determinada pelos parâmetros índice de azul de metileno (IAM), volume de mesoporos e coeficiente Kf, associados aos resultados do experimento de seleção, considerado uma ferramenta técnica alternativa de simples aplicação e suficiente para esse fim.


ABSTRACT The presence of cyanobacteria is a major concern for water treatment, since these microorganisms can be toxic metabolic producers, such as microcystins (MCs), which are not effectively removed in the usually employed full cycle treatment. In order to remove these toxins, it is possible to use absorbers such as activated carbon (AC), which presents a varied efficiency, depending on its characteristics. The general objective of this research was to provide technical and scientific subsidies for the selection of powdered activated carbons (PACs) and granular activated carbons (GACs) in relation to the adsorption of microcystins. A bench scale experiment was carried out to select activated carbons with higher adsorptive capacity for microcystins. Then, for the selected PACs and GACs, complementary characterization was performed for the specific volume distribution as function of pore size and, afterwards, Freundlich adsorption isotherms and breakthrough curves were elaborated. It was possible to verify that among the sampled activated carbons, the imported ones presented greater adsorption capacity for microcystins in relation to the nationals. In addition, it was possible to conclude that the selection of an activated carbon can be done regarding methylene blue index (MBI) parameters, volume of mesoporous and Kf, associated to the selection experiment's results, considered an alternative technical tool of simple application and sufficient for this purpose.

9.
ACS Omega ; 2(2): 653-662, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31457462

RESUMO

A fully nanoporous Fe-rich alloy, prepared by selective dissolution of melt-spun Fe43.5Cu56.5 ribbons, exhibits outstanding properties as a heterogeneous Fenton catalyst toward the degradation of methyl orange (MO) in aqueous solution. In addition, the ferromagnetic characteristics of this material enable its wireless manipulation toward specific locations within polluted wastewater. The influence of selective dissolution on the microstructure, sample morphology (surface and cross-section), elemental composition, and magnetic properties of the resulting nanoporous alloy is investigated. The dealloying procedure enhances the saturation magnetization and drastically increases the catalytic performance (i.e., the time required for full degradation of MO from the medium is reduced by a factor of approximately 2 by subjecting the Fe43.5Cu56.5 ribbons to prior dealloying). Remarkably, the effectiveness of this nanoporous material surpasses the results obtained by the homogeneous Fenton reaction using an equivalent concentration of Fe cations leached into the media from the nanoporous alloy. The different factors that promote the high catalytic activity are discussed. The outstanding catalytic activity, together with the simplicity of the synthetic procedure, makes this material very appealing for water remediation using advanced Fenton processes.

10.
ACS Appl Mater Interfaces ; 7(4): 2677-87, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25569325

RESUMO

The electrosynthesis and characterization of polypyrrole(PPy)/stainless steel electrodes decorated with gold nanoparticles and the performance of the composite electrode for sensing applications is described. PPy films were grown in potassium perchlorate and sodium salicylate solutions under comparable electropolymerization conditions. Polymer films prepared in the presence of perchlorate ions exhibited worm-like structures, whereas columnar structures were obtained in salicylate-containing solutions. Voltammetric response of PPy films prepared in salicylate solutions was more reversible. PPy films were decorated with gold nanoparticles obtained by a double step potentiostatic electrodeposition routine that allowed fine control of deposit characteristics. Analysis of deposits was performed by means of SEM and confocal Raman spectroscopy. The electrocatalytic activity of the Au/PPy electrodes was assessed for the electro-oxidation of hydrazine and hydroxylamine. Results showed a successful optimization of the route of synthesis that rendered nanocomposite electrode materials with promising applications in electrochemical sensing.

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