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1.
Photochem Photobiol Sci ; 22(1): 47-58, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36112308

RESUMO

Pure (TiO2) and 0.1 nominal atomic percent of palladium-modified TiO2 (Pd-TiO2) films were synthesized via a sol-gel method and compared through their physicochemical properties and photocatalytic activity in the degradation of an emerging contaminant, 17-α-ethinylestradiol (EE2). The activity of the films was studied using a continuous flow, planar microreactor under simulated sunlight. Catalysts characterization included X-ray diffraction, UV-Visible diffuse reflectance and transmittance spectroscopy, atomic force microscopy, transmission electron microscopy, Raman spectroscopy, N2 physisorption analysis, and X-ray photoelectron spectroscopy. The modification of TiO2 with palladium confined the size of anatase phase crystallites, increased the specific surface area and improved radiation absorption. PdO domains on TiO2 were observed. In all the tested conditions, higher conversion of EE2 was achieved with the Pd-TiO2 film compared with the TiO2 film, presenting an 80% increase in the reaction rate. The performance of the catalytic films was also assessed by the calculation of two efficiency parameters: radiation absorption efficiency and quantum efficiency of reaction. The Pd-TiO2 film showed a notable enhancement of the absorption of the incident radiation and a more efficient utilization of the absorbed photons to degrade the target pollutant.


Assuntos
Absorção de Radiação , Paládio , Microscopia Eletrônica de Transmissão , Titânio/química , Catálise
2.
J Phys Condens Matter ; 34(24)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35344939

RESUMO

The Ca2MnReO6double perovskite is a spin-orbit-assisted Mott insulator with exotic magnetic properties, including a largely non-collinear Mn2+spin arrangement and nearly orthogonal coupling between such spins and the much smaller Re 5dmagnetic moments. Here, the electron-doped compound Ca1-xYxMnReO6(x= 0.1, 0.2 and 0.3) is reported and a detailed investigation is conducted forx= 0.3. Neutron and x-ray powder diffraction confirm that nearly full chemical order is maintained at the Mn and Re sites under the Y substitution at the Ca site. X-ray absorption measurements and an analysis of the Mn-O/Re-O bond distances show that the Mn oxidation state remains stable at +2 whereas Re is reduced upon doping. The electron doping increases the magnetic ordering temperature fromTc= 121 to 150 K and also enhances significantly the ferromagnetic component of the Mn spins at the expense of the antiferromagnetic component at the base temperature (T= 3 K). The lattice parameter anomalies atTcobserved in the parent compound are suppressed by the electron doping. The possible reasons for the enhanced magnetism and the suppressed magnetoelastic coupling in Ca1.7Y0.3MnReO6are discussed.

3.
Parasit Vectors ; 14(1): 492, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34563255

RESUMO

BACKGROUND: Triatomine bugs transmit Chagas disease across Latin America, where vector control-surveillance is increasingly decentralized. Locally run systems often deal with highly diverse native-vector faunas-plus, in some areas, domestic populations of non-native species. Flexible entomological-risk indicators that cover native and non-native vectors and can support local decision-making are therefore needed. METHODS: We present a local-scale entomological-risk score ("TriatoScore") that leverages and builds upon information on the ecology-behavior and distribution-biogeography of individual triatomine bug species. We illustrate our approach by calculating TriatoScores for the 417 municipalities of Bahia state, Brazil. For this, we (i) listed all triatomine bug species recorded statewide; (ii) derived a "species relevance score" reflecting whether each species is native/non-native and, if native, whether/how often it invades/colonizes dwellings; (iii) mapped each species' presence by municipality; (iv) for native vectors, weighted presence by the proportion of municipal territory within ecoregions occupied by each species; (v) multiplied "species relevance score" × "weighted presence" to get species-specific "weighted scores"; and (vi) summed "weighted scores" across species to get municipal TriatoScores. Using standardized TriatoScores, we then grouped municipalities into high/moderate/low entomological-risk strata. RESULTS: TriatoScores were higher in municipalities dominated by dry-to-semiarid ecoregions than in those dominated by savanna-grassland or, especially, moist-forest ecoregions. Bahia's native triatomines can maintain high to moderate risk of vector-borne Chagas disease in 318 (76.3%) municipalities. Historical elimination of Triatoma infestans from 125 municipalities reduced TriatoScores by ~ 27% (range, 20-44%); eight municipalities reported T. infestans since Bahia was certified free of Trypanosoma cruzi transmission by this non-native species. Entomological-risk strata based on TriatoScores agreed well with Bahia's official disease-risk strata, but TriatoScores suggest that the official classification likely underestimates risk in 42 municipalities. Of 152 municipalities failing to report triatomines in 2006-2019, two and 71 had TriatoScores corresponding to, respectively, high and moderate entomological risk. CONCLUSIONS: TriatoScore can help control-surveillance managers to flexibly assess and stratify the entomological risk of Chagas disease at operationally relevant scales. Integrating eco-epidemiological, demographic, socioeconomic, or operational data (on, e.g., local-scale dwelling-infestation or vector-infection frequencies, land-use change and urbanization, housing conditions, poverty, or the functioning of control-surveillance systems) is also straightforward. TriatoScore may thus become a useful addition to the triatomine bug control-surveillance toolbox.


Assuntos
Doença de Chagas/transmissão , Insetos Vetores/fisiologia , Triatominae/fisiologia , Trypanosoma cruzi/fisiologia , Animais , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Entomologia , Meio Ambiente , Qualidade Habitacional , Humanos , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Fatores de Risco , Triatominae/classificação , Triatominae/parasitologia
4.
Environ Sci Pollut Res Int ; 28(19): 23946-23957, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33398729

RESUMO

The degradation of paracetamol (PCT) in an aqueous medium using the Fenton and photo-Fenton reactions was investigated. The aim of this research was the development of a kinetic model based on a reaction mechanism, which includes two main intermediates of PCT degradation and the local volumetric rate of photon absorption (LVRPA). Ferrioxalate was used as a catalyst and the working pH was adjusted to 5.5 (natural pH). Experimental work was planned through a D-optimal experimental design and performed in a flat plate reactor irradiated by a solar simulator. Hydrogen peroxide (HP) concentration, reaction temperature, and radiation level were the operating parameters. The photo-Fenton reaction allowed to reach a minimum relative PCT concentration of 2.01% compared to 5.04% achieved with Fenton reaction. Moreover, the photo-Fenton system required a 50% shorter reaction time and lower HP concentration than in dark conditions (90 min and 189 mg L-1 vs. 180 min and 334 mg L-1, respectively). The experimental results were used to estimate the kinetic parameters of the proposed kinetic model employing a nonlinear, multi-parameter regression method. The values obtained from the normalized root-mean-square error (14.52, 1.96, 4.36, 13.16, and 8.72 % for PCT, benzoquinone, hydroquinone, HP, and oxalate, respectively) showed a good agreement between the predicted and experimental data.


Assuntos
Acetaminofen , Poluentes Químicos da Água , Absorção de Radiação , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Ferro , Cinética , Oxirredução
5.
Cardiol Young ; 31(4): 654-657, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33308360

RESUMO

Dengue virus can affect the heart, with complications as bradycardia, arrhythmias, and death. We present a case of a 15-year-old patient, diagnosed 4 years before with severe idiopathic pulmonary hypertension, confirmed by catheterism, with continuous follow up. At that time, she was living in Bogotá (2640 m above sea level). Sildenafil and Macitentan were started. She was recommended to live at low altitude and she moved. The patient was transferred back to Bogota, from that place, due to flu-like symptoms and fever. Immunoglobulin M for dengue was confirmed and second-degree atrioventricular block Mobitz I with bradycardia (40 beats/minute) was documented throughout the clinical course. She recovered.


Assuntos
Bloqueio Atrioventricular , Dengue , Hipertensão Pulmonar , Adolescente , Arritmias Cardíacas , Criança , Dengue/complicações , Dengue/diagnóstico , Hipertensão Pulmonar Primária Familiar , Feminino , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/etiologia
6.
Front Chem ; 8: 551710, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195045

RESUMO

The removal of indoor and outdoor air pollutants is crucial to prevent environmental and health issues. Photocatalytic building materials are an energy-sustainable technology that can completely oxidize pollutants, improving in situ the air quality of contaminated sites. In this work, different photoactive TiO2 catalysts (anatase or modified anatase) and amounts were used to formulate photocatalytic paints in replacement of the normally used TiO2 (rutile) pigment. These paints were tested in two different experimental systems simulating indoor and outdoor environments. In one, indoor illumination conditions were used in the photoreactor for the oxidation of acetaldehyde achieving conversions between 37 and 55%. The other sets of experiments were performed under simulated outdoor radiation for the degradation of nitric oxide, resulting in conversions between 13 and 35%. This wide range of conversions made it difficult to directly compare the paints. Thus, absorption, photonic, and quantum efficiencies were calculated to account for the paints photocatalytic performance. It was found that the formulations containing carbon-doped TiO2 presented the best efficiencies. The paint with the maximum amount of this photocatalyst showed the highest absorption and photonic efficiencies. On the other hand, the paint with the lowest amount of carbon-doped TiO2 presented the highest value of quantum efficiency, thus becoming the optimal formulation in terms of energy use.

7.
J Orthod Sci ; 9: 7, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33110766

RESUMO

OBJECTIVES: To evaluate the perception of esthetics and the attractiveness of the smile, in frontal view, with mandibular asymmetry, through the eye-tracking. MATERIALS AND METHODS: OGAMA software and The Eye Tribe Tracker hardware were used to obtain eye tracking in certain areas of interest on the face. To simulate asymmetry, Photoshop® image editing software was used to create a vertical reference line to the midline of the face and make it symmetrical with control of the angulation relative to another horizontal reference line passing through the vertices. Then, the lower third of the face added asymmetries or deviations, starting from zero, with increments of 2 by 2 degrees up to 6 degrees. The study included 60 laypeople, 30 males and 30 females, without any knowledge about the study, showing good vision, and not having used drugs with the possibility of influencing cognitive or motor skills. RESULTS: From the heat map in cases of mandibular asymmetry, it is possible to visualize that for both sexes the evaluators evaluated with a certain degree of similarity mainly when the deviations presented with 6 degrees. The trajectory of the male and female gaze in cases with asymmetry shows that in cases with a magnitude of 6 degrees, the raters traced mainly in the region of the mouth with little transition in the eye region and mainly in the areas of interest considered as "other." In the images presented with a magnitude of up to 4 degrees, they were traced in the general image. CONCLUSIONS: The perception of laypeople from mandibular asymmetry to the right in females presented a higher perception when compared to males with mandible asymmetry to the left.

8.
Isotopes Environ Health Stud ; 56(5-6): 513-532, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32996792

RESUMO

Fluxes between fractured-karstified and detritic aquifers are commonly poorly understood in many environments. These two types of aquifers are in contact in the southeastern Pampean region in the Argentine Buenos Aires province, and the aim of this work is to analyze their relationship contributing to improve the hydrological model. A joint application of hydrochemical and multi-isotope (δ 2H, δ 18O, δ 13C-TDIC, δ 18O-TDIC, 87Sr/86Sr) tools was used. TDIC, δ 2H, δ 18O and δ 13C-TDIC allowed differentiating two main end members. Water in the Pampeano aquifer (PA) which is transferred from the fractured-karstic aquifer (F-KA) is characterised by high TDIC around 500-700 mg/L, isotopically depleted in 18O (about -5.5 ‰) and high δ 13C-TDIC (around -10.0 ‰). The other end member is direct recharge water infiltrated into the PA with TDIC ranging from 400 to 500 mg/L, slightly enriched in 18O (δ 18O = -4.8 ‰), and δ 13C-TDIC in the range of soil CO2 as a result of reactions with calcrete concretions (from -20.0 to -9.0 ‰). Dolomite dissolution is the main process controlling the chemistry of the low-mineralized (Mg-Ca-HCO3) waters, whereas high-mineralized (Na-HCO3) waters are strongly influenced by ion-exchange reactions with adsorbed Ca2+ and Mg2+ and by evaporation.


Assuntos
Monitoramento Ambiental/métodos , Água Subterrânea/química , Isótopos/análise , Argentina , Carbonato de Cálcio/química , Magnésio/química , Solubilidade , Ciclo Hidrológico
9.
Nat Prod Res ; 34(16): 2384-2388, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30761908

RESUMO

The present study aimed to evaluate the antibacterial and modulatory activity of the Turnera subulate methyl extract in isolation or in combination with aminoglycoside antibiotics, using the microdilution method. The Turnera subulata methyl extract was used in isolation in the antibacterial assays and in combination with antibiotics in the modulation assays. All tests were performed in triplicates. The Turnera subulata methyl extract presented both antibacterial and antibiotic-modulatory effects in vitro, in isolation and in association with aminoglycosides. The extract activity depends on the bacterial strain and may be associated with the presence of tannins and flavonols. However, further studies are required to characterize the Turnera subulata potential for the development of new drugs against multiresistant bacteria.


Assuntos
Extratos Vegetais/farmacologia , Turnera/química , Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química
10.
Rev Chilena Infectol ; 36(3): 371-375, 2019 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-31859757

RESUMO

BACKGROUND: Pyomyositis is the infection of skeletal muscle, a rare pathology in children. Aim To describe the characteristics of pyomyositis in pediatric patients. METHODS: Prospective analytical study of hospitalized children diagnosed with pyomyositis from May 2016 to April 2017 at the Ricardo Gutiérrez Children's Hospital, Buenos Aires, Argentina. RESULTS: Twenty-one patients with pyomyositis were identified. Annual rate: 21.5/10,000 admissions (95% CI 4.65-71.43). The median age was 5.4 years (range 1.25-11.6). The lower limbs were the most affected site. C-reactive protein (CRP) was elevated in all patients, with a mean of 124 mg/L (SD 96), being significantly higher in patients with bacteremia: 206 (DS 101) vs 98 (DS 81), p = 0.02. Bacterial cultures were positive in 17/21 (80.9%): 15 methicillin-resistant Staphylococcus aureus (MRSA), and 2 Streptococcus pyogenes. Blood cultures were positive in 5 (23.8%). CONCLUSION: MRSA-community acquired is the predominant pathogen in our setting. In the selection of the appropriate empirical treatment, the local resistance pattern and the CRP value should be taken into account.


Assuntos
Bacteriemia/diagnóstico , Piomiosite/diagnóstico , Infecções Estafilocócicas/diagnóstico , Antibacterianos/uso terapêutico , Argentina , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Proteína C-Reativa/análise , Criança , Pré-Escolar , Clindamicina/uso terapêutico , Drenagem , Feminino , Hospitais Pediátricos , Humanos , Lactente , Extremidade Inferior , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Estudos Prospectivos , Piomiosite/tratamento farmacológico , Piomiosite/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Ultrassonografia , Vancomicina/uso terapêutico
11.
Top Curr Chem (Cham) ; 377(5): 22, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444578

RESUMO

A methodology for photocatalytic reactor modeling applied to advanced oxidation processes for chemical pollution abatement is presented herein. Three distinct reactor configurations typically employed in the field of air and water purification-wall reactors, slurry reactors, and fixed-bed reactors-are considered to illustrate the suggested approach. Initially, different mechanistically derived kinetic expressions to represent the photocatalytic rate of pollutant degradation are reviewed, indicating the main assumptions made by the authors in the published contributions. These kinetic expressions are needed to solve the mass balances of the reactant species in the photocatalytic reactors. As is well known, at least one of the steps of the reaction mechanism requires evaluation of the rate of electron-hole generation, which depends on the photon absorption rate: a volumetric property for reactions with the catalyst particles in aqueous suspension or a surface property for systems with a fixed catalyst deposited on an inert support. Subsequently, the different techniques for evaluating the optical properties of slurry and immobilized systems, and the numerical methods applied to calculate the photon absorption rate, are described. The experimental and theoretical results of pollutant degradation in each reactor type are then presented and analyzed. Finally, the definition, calculation, and relevance of different efficiency parameters are briefly reviewed. Using these illustrative examples, we emphasize the need for a systematic and rigorous approach for photocatalytic reactor modeling in order to overcome the inherent drawbacks of photocatalysis and to improve the overall efficiency of the process.


Assuntos
Luz , Modelos Teóricos , Poluentes Químicos da Água/química , Catálise , Ácido Clofíbrico/química , Cinética , Oxirredução , Fótons , Titânio/química
12.
Rev. chil. infectol ; Rev. chil. infectol;36(3): 371-375, jun. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1013795

RESUMO

Resumen Introducción: La piomiositis es la infección del músculo esquelético, entidad poco frecuente en pediatría. Objetivo: Describir las características de 21 niños con piomiositis. Métodos: Estudio prospectivo-analítico de niños ingresados con diagnóstico de piomiositis entre mayo de 2016 y abril de 2017 en el Hospital de Niños Ricardo Gutiérrez, Buenos Aires, Argentina. Resultados: Tasa de hospitalización de 21,5/10.000 admisiones (IC 95% 4,65- 71,43). La mediana de edad fue de 5,4 años (rango 1,25-11,6). El 90,4% presentaba algún factor predisponente. La localización más frecuente fue en miembros inferiores. La proteína C reactiva (PCR) estuvo elevada en todos los pacientes, con una media de 124 mg/L (DS 96), siendo significativamente más elevada en los pacientes que tuvieron hemocultivos positivos 206 (DS 101) vs 98 (DS 81), (p = 0,02). Se obtuvo rescate microbiológico en 17 pacientes (80,9%): Staphylococcus aureus resistente a meticilina (SARM) (n: 15) y Streptococcus pyogenes (n: 2). Se presentó con bacteriemia 23,8% de los pacientes. El 81% requirió drenaje quirúrgico. Conclusión: Staphylococcus aureus RM adquirido en la comunidad (SARMAC) es el patógeno predominante. En la selección del tratamiento empírico adecuado debería tenerse en cuenta: el patrón de resistencia local y el valor de PCR.


Background: Pyomyositis is the infection of skeletal muscle, a rare pathology in children. Aim To describe the characteristics of pyomyositis in pediatric patients. Methods: Prospective analytical study of hospitalized children diagnosed with pyomyositis from May 2016 to April 2017 at the Ricardo Gutiérrez Children's Hospital, Buenos Aires, Argentina. Results: Twenty-one patients with pyomyositis were identified. Annual rate: 21.5/10,000 admissions (95% CI 4.65-71.43). The median age was 5.4 years (range 1.25-11.6). The lower limbs were the most affected site. C-reactive protein (CRP) was elevated in all patients, with a mean of 124 mg/L (SD 96), being significantly higher in patients with bacteremia: 206 (DS 101) vs 98 (DS 81), p = 0.02. Bacterial cultures were positive in 17/21 (80.9%): 15 methicillin-resistant Staphylococcus aureus (MRSA), and 2 Streptococcus pyogenes. Blood cultures were positive in 5 (23.8%). Conclusion: MRSA-community acquired is the predominant pathogen in our setting. In the selection of the appropriate empirical treatment, the local resistance pattern and the CRP value should be taken into account.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Infecções Estafilocócicas/diagnóstico , Bacteriemia/diagnóstico , Piomiosite/diagnóstico , Argentina , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Proteína C-Reativa/análise , Clindamicina/uso terapêutico , Vancomicina/uso terapêutico , Drenagem , Estudos Prospectivos , Ultrassonografia , Bacteriemia/microbiologia , Bacteriemia/tratamento farmacológico , Extremidade Inferior , Piomiosite/microbiologia , Piomiosite/tratamento farmacológico , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Hospitais Pediátricos , Antibacterianos/uso terapêutico
13.
BMC Infect Dis ; 19(1): 403, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31077143

RESUMO

BACKGROUND: Implementation of sputum Gram stain in the initial assessment of community-acquired pneumonia (CAP) patients is still controversial. We performed a systematic review and meta-analysis to investigate the usefulness of sputum Gram stain for defining the etiologic diagnosis of CAP in adult patients. METHODS: We systematically searched the Medline, Embase, Science Direct, Scopus and LILACS databases for full-text articles. Relevant studies were reviewed by at least three investigators who extracted the data, pooled them using a random effects model, and carried out quality assessment. For each bacterium (Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, and Gram-negative bacilli), pooled sensitivity, specificity, positive and negative likelihood ratios were reported. RESULTS: After a review of 3539 abstracts, 20 articles were included in the present meta-analysis. The studies included yielded 5619 patients with CAP. Pooled sensitivity and pooled specificity of sputum Gram stain were 0.59 (95% CI, 0.56-0.62) and 0.87 (95% CI, 0.86-0.89) respectively for S. pneumoniae, 0.78 (95% CI, 0.72-0.84) and 0.96 (95% CI, 0.94-0.97) for H. influenzae, 0.72 (95% CI, 0.53-0.87) and 0.97 (95% CI, 0.95-0.99) for S. aureus, and 0.64 (95% CI, 0.49-0.77) and 0.99 (95% CI, 0.97-0.99) for Gram-negative bacilli. CONCLUSION: Sputum Gram stain test is sensitive and highly specific for identifying the main causative pathogens in adult patients with CAP. TRIAL REGISTRATION: This study has been registered at PROSPERO International prospective register of systematic reviews under registration no. CRD42015015337 .


Assuntos
Bactérias/isolamento & purificação , Infecções Comunitárias Adquiridas/diagnóstico , Violeta Genciana , Fenazinas , Pneumonia/diagnóstico , Escarro/microbiologia , Coloração e Rotulagem , Bactérias/classificação , Infecções Comunitárias Adquiridas/microbiologia , Haemophilus influenzae , Humanos , Pneumonia/microbiologia , Staphylococcus aureus , Streptococcus pneumoniae
14.
Environ Sci Pollut Res Int ; 26(13): 12720-12730, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30877547

RESUMO

A regional raw clay was used as the starting material to prepare iron-pillared clays with different iron contents. The catalytic activity of these materials was tested in the heterogeneous photo-Fenton process, applied to the degradation of 2-chlorophenol chosen as the model pollutant. Different catalyst loads between 0.2 and 1.0 g L-1 and pH values between 3.0 and 7.0 were studied. The local volumetric rate of photon absorption (LVRPA) in the reactor was evaluated solving the radiative transfer equation applying the discrete ordinate method and using the optical properties of the catalyst suspensions. The photonic and quantum efficiencies of the 2-chlorophenol degradation depend on both the catalyst load and the iron content of the catalyst. The higher values for these parameters, 0.080 mol Einstein-1 and 0.152 mol Einstein-1, respectively, were obtained with 1.0 g L-1 of the catalyst with the higher iron content (17.6%). For the mineralization process, photonic and quantum efficiencies depend mainly on the catalyst load. Therefore, it was possible to employ a natural and cheap resource from the region to obtain pillared clay-based catalysts to degrade organic pollutants in water.


Assuntos
Argila/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Catálise , Clorofenóis/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Ferro/química , Fótons , Purificação da Água/instrumentação
16.
J Investig Clin Dent ; 10(2): e12391, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30680921

RESUMO

The purpose of the present systematic review was to evaluate the effectiveness of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-containing products in the prevention and treatment of active white spot lesions (WSL) in orthodontic patients. Searched the Scopus, PubMed, Web of Science, Cochrane, Virtual Health Language, ClinicalTrials, and Open Gray databases without limitations on the year or language of publication. We included controlled clinical trials with patients with fixed orthodontic appliances under the use of CPP-ACP-containing products compared to control, placebo, or other interventions in the prevention and treatment of WSL around orthodontic braces. Case reports, editorials, in vitro studies, annals of congress, and reviews were excluded. To assess the risk of bias, the revised version of the Cochrane tool for randomized trials (RoB 2.0) and Risk Of Bias In Non-randomized Studies for non-randomized trials were used. The biases were graded low, moderate, and high according to the tools used. Of the 599 articles found, 11 met the inclusion criteria. Of these, nine were randomized, controlled clinical trials and two were non-randomized. Two studies were considered to have moderate bias risk, and the most-used CPP-ACP presented form was a cream for topical applications. Although CPP-ACP-containing products did not differ from other fluoride products, they were able to reduce WSL and neutralize the pH around the orthodontic braces. Products containing CPP-ACP are effective in preventing and treating WSL around the braces. However, further studies with the same measurement method and periods of use, and other forms of presentation of CPP-ACP are needed.


Assuntos
Caseínas , Cárie Dentária , Fosfatos de Cálcio , Cariostáticos , Humanos , Fosfopeptídeos , Remineralização Dentária
17.
Environ Sci Pollut Res Int ; 26(5): 4192-4201, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29860698

RESUMO

SBA-15 and KIT-6 materials have been synthesized and modified with iron salts by the wet impregnation method with different metal loadings. The different mesostructures obtained were characterized by N2 adsorption-desorption at 77 K, X-ray diffraction, temperature-programmed reduction, and ultraviolet-visible spectroscopy. These iron-containing mesostructured materials have been successfully tested for the heterogeneous photo-Fenton degradation of aqueous solutions of dangerous herbicides, such as atrazine, using UV-visible light irradiation, at room temperature and close to neutral pH. The results showed that the Fe/SBA-15 (10%) and Fe/KIT-6 (5%) catalysts exhibited the highest activities. However, the Fe/KIT-6 (5%) catalyst with minor Fe loading than Fe/SBA-15 (10%) presented a higher degradation of atrazine (above 98% in a reaction time of 240 min). Therefore, the interconnectivity of the cage-like mesopores had an important influence on the catalytic activity, favoring probably mass-transfer effects. Thus, the high performance of these materials indicates that the heterogeneous via of photo-Fenton process can also be efficiently employed to treat wastewaters containing pollutants such as herbicides, in order to reduce them to simplest and less toxic molecules.


Assuntos
Atrazina/análise , Peróxido de Hidrogênio/química , Ferro/química , Dióxido de Silício/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Catálise , Concentração de Íons de Hidrogênio , Luz , Processos Fotoquímicos , Porosidade , Propriedades de Superfície , Águas Residuárias/química
18.
J Hazard Mater ; 372: 113-120, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29678309

RESUMO

The effects of four inorganic anions (Cl-, SO42-, HCO3-, NO3-) usually present in groundwater were investigated on the photo-Fenton degradation of 2,4-dichlorophenoxyacetic acid (2,4-D). A kinetic model derived from a reaction sequence is proposed using the ferrioxalate complex as iron source at pH close to natural conditions (pH = 5). It was demonstrated that oxalate not only maintained iron in solution for the natural groundwater system, but also increased the photochemical activation of the process. Results showed that the minimum conversion of 2,4-D for the simulated groundwater after 180 min was 63.80%. This value was only 14.1% lower than the conversion achieved without anions. However, with all anions together, the consumption of hydrogen peroxide (HP) per mole of herbicide showed an increase with respect to the test without anions. Only one kinetic parameter was estimated for each anion applying a nonlinear regression method. Subsequently, these optimized kinetic constants were used to simulate the system behaviour, considering the influence of all the studied anions together. A good agreement between kinetic model predictions and experimental data was observed, with the following errors: RMSE2,4-D = 3.98 × 10-3 mM, RMSEHP = 1.83 × 10-1 mM, RMSEOX = 1.39 × 10-2 mM, and RMSE2,4-DCP = 5.59 × 10-3  mM.

19.
Photochem Photobiol Sci ; 18(4): 884-890, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30427037

RESUMO

The photocatalytic inactivation of Bacillus subtilis spores in air was evaluated employing a fixed-bed reactor with TiO2-coated glass rings, under artificial UV-A radiation. Calculations of the radiation effectively absorbed inside the reactor were carried out by Monte Carlo simulations. The photocatalytic inactivation was assessed by analyzing the viability of the microorganisms retained by the coated glass rings inside the reactor at different irradiation periods. The initial concentration of the spores was reduced by almost 55% at the end of the experiment (12 h). Complementary assays were carried out employing Bacillus subtilis vegetative cells, obtaining a reduction of more than 96% under the same conditions. Two efficiency parameters were computed to assess the reactor performance: the photonic efficiency and the quantum efficiency of inactivation. Results of the efficiency parameters allow an objective comparison of the reactor performance under different experimental conditions and configurations.


Assuntos
Microbiologia do Ar , Bacillus subtilis/efeitos da radiação , Vidro/química , Esporos Bacterianos/efeitos da radiação , Esterilização/instrumentação , Titânio/química , Poluição do Ar em Ambientes Fechados , Catálise , Desenho de Equipamento , Método de Monte Carlo , Processos Fotoquímicos , Raios Ultravioleta/efeitos adversos
20.
Interacciones ; 4(3): 153-162, 01 de septiembre de 2018.
Artigo em Espanhol | LILACS | ID: biblio-981368

RESUMO

La espiritualidad se define como la capacidad multidimensional de búsqueda de sentido y conexión en las relaciones con uno mismo, con las demás personas, con la naturaleza o lo sagrado. El objetivo de este estudio fue examinar la fiabilidad y la estructura factorial de la versión revisada de la Escala de Espiritualidad Personal (EEP-R) en adultos puertorriqueños. Un total de 577 puertorriqueños participaron en este estudio de carácter confirmatorio y psicométrico. Los resultados confirmaron que la escala posee una estructura multidimensional. Estas dimensiones son Conexión Intrapersonal, Conexión Interpersonal y Conexión Transpersonal. Los doce ítems de la escala cumplieron con los criterios de discriminación y los índices de confiabilidad obtenidos para la escala fluctuaron entre .81 y .95. En síntesis, la EEP-R cuenta con las propiedades psicométricas adecuadas para seguir con estudios de validación, así como para implementarla en diversas líneas de trabajo, tanto teóricas como aplicadas.


Spirituality is defined as the multidimensional capacity of search for meaning and connection in relationships with oneself, other people, nature or the sacred. The aim of this study was to analyze the reliability and factor structure of Personal Spirituality Scale (PSS-R) in a sample of Puerto Ricans adults. A total of 577 Puerto Ricans participated in this psychometric study. The results confirmed that the PSS has a multidimensional structure. These dimensions were Intrapersonal Spirituality, Interpersonal Spirituality and Transpersonal Spirituality. The twelve items complied with the criteria of discrimination. The reliability index obtained fluctuated between .81 to .95. The PSS-R has appropriate psychometric properties useful for validation studies. It can be used in different lines of research, theoretical as well as applied.

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