Resumo As doenças bacterianas são fatores importantes que limitam a produtividade na aquicultura. Para reduzir os impactos econômicos negativos, os piscicultores utilizam antimicrobianos, muitas vezes de forma indiscriminada, e essa ação tem levado à resistência bacteriana aos medicamentos. Os objetivos deste estudo foram isolar e identificar as principais bactérias com potencial putativo para o tambaqui (Colossoma macropomum), e estabelecer o perfil de resistência a antimicrobianos pelos métodos de difusão em disco e valores de concentração inibitória mínima (CIM). Duzentos e noventa peixes assintomáticos foram coletados entre março e novembro de 2015, em dez pisciculturas do estado do Amazonas (Brasil). Do total de cepas recuperadas de tambaqui, sete foram identificadas como Aeromonas spp. pelo sequenciamento do gene 16S rRNA. Esses sete isolados apresentaram resistência à ampicilina, 28% à eritromicina e 28% à sulfonamida. Além disso, os sete isolados apresentaram CIM superior à faixa avaliada para amoxicilina, penicilina, novobiocina, tartarato de tilosina e clindamicina, e 85% apresentaram resistência à eritromicina. Os resultados deste estudo indicam a necessidade de aumentar a conscientização dos piscicultores e, principalmente, do poder público, a falta de regulamentação de medicamentos para uso na aquicultura e sobre as boas práticas de manejo, para que o uso profilático e sistêmico de antimicrobianos de forma indiscriminada seja inibido.

Abstract Bacterial diseases are important factors that limit productivity in aquaculture. To reduce negative economic impacts, fish farmers use antimicrobials, often indiscriminately, and this action has led to bacterial resistance to drugs. The objectives of this study were to isolate and identify the main putative pathogenic bacterial species in tambaqui (Colossoma macropomum), establish the profile of resistance to antimicrobials by the methods of disc diffusion, and determine the minimum inhibitory concentration (MIC) values. Two hundred and ninety asymptomatic fish were collected between March and November 2015 from ten fish farms in the Amazonas state (Brazil). Of the total strains recovered from tambaqui, seven were identified as Aeromonas spp. by sequencing the 16S rRNA gene. These seven isolates showed resistance to ampicillin, 28% to erythromycin, and 28% to sulfonamide. Additionally, the seven isolates showed a MIC higher than the range evaluated for amoxicillin, penicillin, novobiocin, tylosin tartrate, and clindamycin, and 85% showed resistance to erythromycin. The results of this study indicate the need to increase the awareness of fish farmers and, most importantly, the government, about the lack of drug regulations for use in aquaculture, and good management practices, so the indiscriminate prophylactic and systemic use of antimicrobials be inhibited.

ABSTRACT The phenomena of infiltration and the percolation of water in the soil are of fundamental importance for the evaluation of runoff, groundwater recharge, evapotranspiration, soil erosion and transport of chemical substances in surface and groundwater. Within this context, the quantitative determination of the infiltration values is extremely important for the different areas of knowledge, in order to evaluate, mainly the surface runoff. Several types of changes in vegetation cover and topography result in significant changes in the infiltration process, making it necessary to use mathematical models to assess the consequences of these changes. Thus, this paper aims to implement the Green-Ampt model using two numerical methods - Newton-Raphson method and W-Lambert function - to determine soil permeability parameters - K and matric potential multiplied by the difference between initial and of saturation - ψ∆θ comparing them to the real data obtained in simulations using an automatic rainfall simulator from the Federal University of Goiás - UFG. The Green-Ampt model adjusted well to the data measured from the rain simulator, with a determination coefficient of 0.978 for the Newton-Raphson method and 0.984 for the W-Lambert function.

Abstract: Introduction: The tibial plateau fractures due to high-energy mechanisms are serious injuries that occur on a load bearing joint. These are difficult to approach because, also affect the bone structure of the leg, they usually have associated soft tissue injuries. Objective: To evaluate the radiological and functional results of high-energy tibial plateau fractures with a minimum follow-up of one year. Material and methods: Retrospective, observational and multicenter study. Analysis of radiological and functional outcomes in the treatment of high-energy tibial plateau fractures, treated by open reduction and internal fixation (ORIF) between 2014 and 2019. Results: 54 fractures treated by ORIF. Follow-up one year. 98.1% consolidation in 13 weeks on average. 83.4% without alterations of the axis in the coronal plane. 74% without postoperative joint widening. Functional scores: Lysholm 82.1 average points and Oxford Knee Score (OKS) 39.5 average points. Conclusion: The joint range of motion was reduced after a high-energy tibial plateau fracture, but with good functional results. The less off axis and less post-operative radiographic widening, the better results are obtained.

Resumen: Introducción: Las fracturas de platillo tibial por mecanismos de alta energía son lesiones graves que ocurren sobre una articulación de carga. Son difíciles de abordar, ya que además de afectar la estructura ósea de la pierna suelen tener lesiones de partes blandas asociadas. Objetivo: Evaluar los resultados radiológicos y funcionales de las fracturas de platillo tibial de alta energía con un mínimo seguimiento de un año. Material y métodos: Estudio retrospectivo, observacional y multicéntrico. Análisis de los resultados radiológicos y funcionales en el tratamiento de fracturas de platillo tibial de alta energía tratadas mediante reducción abierta y fijación interna (RAFI) entre 2014 y 2019. Resultados: 54 fracturas tratadas mediante RAFI. Seguimiento un año, 98.1% de consolidación en 13 semanas de promedio, 83.4% sin alteraciones del eje en plano coronal, 74% sin ensanchamiento articular postoperatorio. Escalas funcionales: Lysholm 82.1 puntos promedio y Oxford Knee Score (OKS) 39.5 puntos promedio. Conclusión: El rango de movilidad articular se redujo luego de una fractura de platillos tibiales de alta energía, pero con buenos resultados funcionales. Cuanto menor deseje y menor ensanchamiento radiográfico postoperatorio, se obtienen mejores resultados.

ABSTRACT: The odontogenic keratocyst is a lesion with specific clinical and histopathological aspects. The World Health Organization (WHO) in 2017 reclassified it from a tumor to a cyst. It is characterized as a cyst of epithelial development of the jaws, arising from the remains of the dental blade. It represents 3 % to 11 % of all odontogenic cysts and 7 to 11 % of cysts of the gnatic bones. It stands out for its aggressive nature and high relapsing potential. Most of the cases are diagnosed in individuals between 10 and 40 years old, with a mild preference for the masculine gender, occurring more in the mandible. Radiographically, it is radiolucent and well delimited, predominantly unilocular, and may cause displacement of adjacent teeth. The present study aims to report a clinical case of a female 25 years old patient, presenting an intra-osseous lesion in the maxilla (posterior, left side), asymptomatic, with a slight increase in intraoral buccal volume, containing the tooth 28, with a diagnostic hypothesis of Odontogenic Keratocyst. The patient was submitted to the surgical decompression treatment, with cystic fluid puncture, biopsy of the lesion and posterior anatomopathological examination. The enucleation of the tumor was performed using LeFort I osteotomy of maxilla and reconstruction with titanium mesh. There is radiographic evidence of bone repair and lesion reduction. The patient is in periodic follow-up of 4 years and does not present clinical and radiographic signs of relapse. Due to the aggressiveness of the odontogenic keratocyst, the relapse rate is high. The knowledge of the techniques recommended for the treatment of Odontogenic Keratocysts and the clinical and radiographic follow-up of the patient demonstrate a gradual decrease of the lumen of the lesion and suggest local bone neoformation, favoring the prognosis of the case.

RESUMEN: El queratoquiste odontogénico es una lesión con aspectos clínicos e histopatológicos específicos. La Organización Mundial de la Salud (OMS) en 2017 lo reclasificó de un tumor a un quiste. Se caracteriza como un quiste de desarrollo epitelial de las mandíbulas, que surge de los restos de la lámina dental. Representa del 3 % al 11 % de todos los quistes odontogénicos y del 7 al 11 % de los quistes de los huesos gnáticos. Se destaca por su naturaleza agresiva y su alto potencial de recaídas. La mayoría de los casos se diagnostican en individuos de entre 10 y 40 años, con una leve preferencia por el sexo masculino, que ocurre más en la mandíbula. Radiográficamente, es radiotransparente y bien delimitado, predominantemente unilocular, y puede causar el desplazamiento de los dientes adyacentes. El presente estudio tiene como objetivo reportar el caso clínico de una paciente de 25 años, que presenta una lesión intraósea en el maxilar (posterior, lado izquierdo), asintomática, con un ligero aumento en el volumen bucal intraoral, que contiene el diente 28, con una hipótesis diagnóstica de queratoquiste odontogénico. El paciente fue sometido al tratamiento quirúrgico de descompresión, con punción de líquido quístico, biopsia de la lesión y examen anatomopatológico posterior. La enucleación del tumor se realizó con osteotomía LeFort I de maxilar y reconstrucción con malla de titanio. Existe evidencia radiográfica de reparación ósea y reducción de la lesión. El paciente se encuentra en seguimiento periódico de 4 años y no presenta signos clínicos ni radiográficos de recaída. Debido a la agresividad del queratoquiste odontogénico, la tasa de recaída es alta. El conocimiento de las técnicas recomendadas para el tratamiento de los queratoquistes odontogénicos, y el seguimiento clínico y radiográfico del paciente, demuestran una disminución gradual del lumen de la lesión y sugieren neoformación ósea local, favoreciendo el pronóstico del caso.

ABSTRACT: Many orthodontic treatments alone cannot reestablish an ideal occlusion, requiring correction through orthognathic surgery. An adequate surgical planning, execution and case follow-up can provide surgical stability between the maxilla and the mandible. Soft tissue conservation and proper correction during a healing phase are important to achieving this goal. Patient C.L.B.S, 38 years old, female, presented with Angle Class I occlusion, facial profile class II, maxilla with mobility, chin surgically advanced and anterior open bite. She was submitted to orthognathic surgery 10 years ago. In the panoramic radiography the absence of bone formation in the maxilla was observed, causing an open bite. For the surgery conventional radiographs were used, as well as the dental cast in articulator for model surgery and preparation of surgical guide. With the surgery an improvement in the patient's aesthetics profile and an ideal occlusion, static and functional were expected. The treatment was orthodontic-surgical, with correction of the dento-facial deformity with counter-clockwise rotation of the maxilla, lowering repositioning in 3 mm of its posterior portion through Le Fort I osteotomy, advancement of the 4 mm mandible with bilateral sagittal osteotomy, and genioplasty for posterior repositioning with a Z-osteotomy, to improve mentual harmony. There was an improvement in the profile and aesthetics of the patient, which developed an Angle Class I profile, a decrease in the mentual projection, and an aesthetic and functional improvement. The orthognathic surgery allowed the advancement of the mandible, the repositioning of the maxilla and the mentual posterior repositioning, obtaining the correction of the Angle class II profile and the anterior open bite, resulting in an important improvement of facial profile and esthetics, presence of skeletal stability, restoration of function, self-esteem and quality of life.

RESUMEN: En muchos casos, el tratamiento ortodóntico por si solo no puede restablecer una oclusión ideal, siendo necesaria una cirúrgia ortognática. Una buena planificación quirúrgica, ejecución y seguimiento del caso, pueden proporcionar estabilidad entre los maxilares. La preservación de los tejidos blandos y una fijación adecuada son esenciales para ese objetivo. La paciente CLBS, 38 años, se presentó con oclusión Clase I de Angle, teniendo perfil clase II, maxilar con movilidad, mentón quirúrgicamente avanzado y mordida abierta anterior. La paciente fue sometida a cirugía ortognática 10 años antes. En radiografía panorámica, se nota la ausencia de formación ósea debido a una fijación maxilar realizada erróneamente, lo que causó la mordida abierta. Durante la planificación, fueron utilizadas radiografías convencionales, modelos de yeso en articulador para cirugía de modelo y confección de guía quirúrgica. Con el procedimento quirúrgico se esperaba obtener una mejora en el perfil de la paciente y una oclusión ideal, estática y funcional. El tratamiento fue ortodóntico-quirúrgico, con corrección de la deformidad dento-facial con giro antihorario de la mandíbula, con reposicionamiento inferior de 3 mm de su parte posterior, por medio de osteotomía Le Fort I, avance de la mandíbula de 4 mm con osteotomía sagital bilateral, y retroceso del mentón en su posición original con osteotomía en Z, mejorando la armonía del mentón. Hubo una mejora en perfil y en la estética de la paciente, como también una mejora en el perfil, estética y funcionalidade, con diminución del mentón. La cirúrgia ortognática permitió el movimiento de la mandíbula, reposicionamiento maxilar y además fue posible retroceder el mentón, obteniendo la corrección del perfil Clase II y de la mordida abierta anterior. El resultado representa una mejora del perfil y de la estética facial, además se nota una estabilidad esquelética, con restablecimiento de la función, autoestima y calidad de vida.

Resumo Objetivo: Descrever a incidência, a apresentação clínica e a evolução dos casos de endoftalmites ocorridos em um centro oftalmológico no Brasil. Métodos: Trata-se de uma revisão de prontuários dos pacientes submetidos à cirurgia de catarata no período de 2008 a 2014. Foram avaliadas as variáveis clínicas associadas ao desfecho de endoftalmite pós-operatória. Resultados: durante o período do estudo, foram realizadas 27.609 cirurgias de catarata. Foram identificados 35 casos de endoftalmite. A incidência global de endoftalmite foi de 0,13%, com variação anual de 0,04% a 0,27%. Os principais sinais e sintomas em pacientes com endoftalmite foram dor ocular e baixa acuidade visual associado à hiperemia conjuntival e hipópio. Os microrganismos gram-positivos foram os agentes etiológicos mais frequentes. Todos os pacientes receberam uma injeção intravítreo de antibióticos como tratamento imediato. A acuidade visual final foi igual ou pior que a capacidade de contar os dedos do examinador em 57,1% dos pacientes. Evisceração ou enucleação foi necessário em 3 pacientes. Conclusão: A incidência de endoftalmite e a maioria dos sinais e sintomas encontrados neste estudo estão de acordo com os reportados na literatura. Embora a taxa de incidência seja baixa, a perda de visão experimentada pela maioria dos pacientes com endoftalmite após a cirurgia de catarata destaca a necessidade de esforços para medidas de prevenção de infecção e diagnóstico precoce para evitar tais complicações.

Abstract Purpose: This study aims to describe the incidence, clinical presentation, and evolution of endophthalmitis cases occurred at an ophthalmologic center in Brazil. Methods: This is a review of medical records of patients undergoing cataract surgery from 2008 to 2014. Clinical variables associated with the outcome of postoperative endophthalmitis were evaluated. Results: during the study period, 27,609 cataract surgeries were performed. It was identified 35 cases of endophthalmitis. The overall incidence of endophthalmitis was 0.13%, with an annual variation from 0.04% to 0.27%. The main signs and symptoms in patients with endophthalmitis were ocular pain and low visual acuity associated with conjunctival hyperemia and hypopyon. Gram-positive microorganisms were the most frequent etiological agents. All patients received an intra-vitreous injection of antibiotics as immediate treatment. The final visual acuity was equal to or worse than the ability to count the examiner's fingers in 57.1% of the patients. Evisceration or enucleation was required in 3 patients. Conclusion: The incidence of endophthalmitis and the majority of signs and symptoms found in this study were in agreement with literature in the field. Although the incidence rate is low, the loss of vision experienced by most patients with endophthalmitis after cataract surgery highlights the need for efforts to prevent infection and early diagnosis to avoid such complications.

Introduction: Around the world, risk factors for fistula failure have been considered in vascular access planning in order to improve results. However, primary fistula failure rates seem to be increasing. Considering this, we conducted a study to identify relevant factors for early fistula failure in a Portuguese cohort with end-stage kidney disease. Subjects and Methods: Retrospective case-control study which included patients from a hospital center who underwent fistula construction between 2012 and 2015. Patients with fistula failure at 6 weeks were matched with consecutive controls in a proportion of 1:1. Clinical and laboratory data were retrieved. Multiple regression analysis was performed to identify factors associated with early complications. Results: Total of 100 predialysis patients with fistula failure at 6 weeks. Mean age of 67.7±11.9 years; most were women (n=54). Factors associated with overall risk of complications were distal location of fistula (OR 2.8; p<0.05) and diabetes mellitus (OR 3.8; p<0.05). Congestive heart failure (OR 7.2; p=0.06) was associated with a tendency for greater risk of inflow complications. Conclusions: In this cohort, despite improvements in vascular access planning, traditional risk factors still have a significant impact on fistula outcomes. The role of “new” factors is still undefined and further studies are needed. An adequate patient education, an organized vascular access program with nurses, nephrologists and surgeons with expertise, with systematic use of Doppler ultrasound, are key factors for better outcomes

Abstract In this paper we present some new cosmological solutions in massive gravity theory. Some homogeneous and isotropic solutions correctly describe accelerated evolutions for the universe. The study was realized considering a specific form to the fiducial metric and found different functions and constant parameters of the theory that guarantee the conservation of the energy momentum tensor. Several accelerating cosmologies were found, all of them reproducing a cosmological constant term proportional to the graviton mass, with a de Sitter type solution for the scale factor. We have also verified that when the fiducial metric is close to the physical metric the solutions are absent, except for some specific open cases.

Resumen En este trabajo presentamos algunas nuevas soluciones en la teoría de gravedad masiva. Algunas soluciones homogéneas e isotrópicas describen correctamente evoluciones aceleradas de nuestro universo. Hicimos la investigación con formas específicas de la métrica fiducial y sin embargo encontramos en la teoría distintas funciones y para ́metros constantes que garantizan la conservación de energía y momento. Se encontraron varias cosmologías y en todas se constata la reproducción de un término de constante cosmológica que es proporcional a la masa del gravitón con una solución del tipo Sitter para el factor de escala. También hemos comprobado que no hay soluciones cuando la métrica de referencia esta ́ cerca de la métrica física, con excepción de algunos casos específicos, aunque abiertos.

Resumo O crescimento populacional em áreas urbanas causa alterações em ecossistemas aquáticos continentais com consequência sobre as comunidades de macrófitas. Este fato vem ocorrendo nos municípios que margeiam o rio Capibaribe, Pernambuco, Brasil. Este trabalho analisa os efeitos da urbanização sobre a composição e estrutura das macrófitas em trechos do referido Rio. Levando em consideração áreas urbanizadas e não urbanizadas, foram escolhidos os seguintes Pontos de Coleta: Pontos 1 e 2 no Município de Santa Cruz do Capibaribe, Pontos 3 e 4 no Município de Toritama, Pontos 5 e 6 na Região Metropolitana do Recife. Estes pontos foram visitados bimestralmente (janeiro – julho/2013), para a observação da variação sazonal (estações seca e chuvosa). Foram identificadas 31 espécies. Geralmente, os pontos das áreas não urbanizadas apresentaram um número maior de espécies. As análises multivariadas indicaram diferenças globais significativas entre áreas urbanizadas e não urbanizadas (R = 0,044, p < 0,001) e também entre as estações (R = 0,018; p < 0,019). Devido à grande variação física, química e biológica entre as áreas urbanizadas e não urbanizadas, observou-se que o fator urbanização influenciou significativamente na composição florística e na estrutura das comunidades de macrófitas.

Abstract Population growth in urban areas changes freshwater ecosystems, and this can have consequences for macrophyte communities as can be seen in the municipalities that border the Capibaribe River, Pernambuco, Brazil. This study reports the effects of urbanization on the composition and structure of macrophyte communities in areas along that river. The following urbanized and non-urbanized sampling sites were chosen: Sites 1 and 2 (municipality of Santa Cruz do Capibaribe), Sites 3 and 4 (municipality of Toritama), and Sites 5 and 6 (metropolitan region of Recife). These sites were visited every two months from January to July 2013 to observe seasonal variation (wet and dry seasons). Thirty-one species were identified. Generally, the non-urbanized sites had a higher number of species. Multivariate analyses indicated significant overall differences between urbanized and non-urbanized areas (R = 0.044; p < 0.001) and between seasons (R = 0.018; p < 0.019). Owing to the large variation in physical, chemical, and biological characteristics between urbanized and non-urbanized areas, we found that urbanization significantly influenced the floristic composition and structure of macrophyte communities.

The study aimed to analyze the occupational stress and coping strategies used by technicians and nursing assistants of a university hospital as well as its association with sociodemographic variables. Method: This is a cross-sectional study with a random sample of 310 technicians and nursing assistants. It was intended for evaluation of occupational stress and coping strategies applied to Job Stress Scale and the Scale Mode Confronting problems. The sample was mostly composed of women, with a mean age of 47.1 years, married or with a partner, who were nursing assistants, with only one employment and who had withdrawal the previous year. Of them, 17.1% of the sample was highly exposed to occupational stress. Results: The strategies focused on the problem proved to be protective with respect to stress. Conclusion: This way of dealing with stressors in the hospital can be optimally worked among professionals.

Objetivo: O estudo objetivou analisar o estresse ocupacional e as estratégias de enfrentamento utilizadas por técnicos e auxiliares de enfermagem de um hospital universitário, bem como a sua associação com variáveis sociodemográficas.Método: Estudo transversal realizado com uma amostra aleatorizada de 310 técnicos e auxiliares de enfermagem. Para avaliação do estresse ocupacional e estratégias de enfrentamento aplicou-se a Job Stress Scale e a Escala Modos de Enfrentamento de Problemas. A amostra foi composta por uma maioria de mulheres, com idade media de 47,1 anos, casados ou com companheiro, auxiliares de enfermagem, com único vínculo empregatício e que tiveram afastamento do trabalho no último ano. Estavam altamente expostos ao estresse ocupacional 17,1% da amostra. Resultados: As estratégias focadas no problema mostraram-se protetoras em relação ao estresse. Conclusiones: Esta forma de lidar com os estressores em ambiente hospitalar pode ser trabalhada de forma otimizada entre os profissionais.

El objetivo del estudio fue analizar el estrés laboral y las estrategias de afrontamiento utilizadas por técnicos y auxiliares de enfermería de un hospital universitario, así como su asociación con variables sociodemográficas. Método: Estudio transversal con una muestra aleatoria de 310 técnicos y auxiliares de enfermería. Para la evaluación del estrés laboral y las estrategias de afrontamiento se aplicó la Job Stress Scale y la Escala Modos de Enfrentamiento de Problemas. La muestra se compone de una mayoría de mujeres, con una edad media de 47,1 años, casadas o en pareja, auxiliares de enfermería, con único vínculo de empleo y que tuvieron trabajo en el último año. Estuvieron altamente expuestas al estrés laboral 17,1% de la muestra. Resultados: Las estrategias centradas en el problema resultaron ser protectoras en relación al estrés. Conclusiones: Esta manera de hacer frente a los factores de estrés en el hospital se puede trabajar de manera optimizada entre los profesionales.

Abstract: In this work we analysed some cosmological bounds concerning an open FLRW solution oí massive gravity. The constraints from recent observational H(z) data are found and the best fit values for the cosmological parameters are in agreement with the ɅCDM model, and also point to a nearly open spatial curvature, as expected from the model. The graviton mass dependence with the constant parameters α 3 and α4 related to the additional lagrangians terms of the model, are also analysed, and we obtain a strong dependence on such parameters, although the condition m g ≃ H 0 -1 seems dominant for a large range of the parameters α 3 and α4.

Resumen: En este trabajo analizamos algunos límites cosmológicos dados por una solución FLRW para la gravedad masiva. Encontramos los límites para datos observacionales recientes de H(z) y mostramos que los mejores ajustes para los valores de los parámetros cosmológicos concuerdan con el modelo ɅCDM e indican una curvatura espacial aproximadamente abierta, como se espera. También se analiza la variación de la masa del gravitón con las constantes α 3 y α4 relacionadas con los términos lagrangianos adicionales del modelo, y se obtiene una fuerte dependencia de tales parámetros. Sin embargo, la condición m g ≃ H 0 -1 parece dominar en un intervalo amplio de los parámetros α 3 y α4.

Através do método dos precursores poliméricos foram sintetizadas amostras de Ca0,98Sr0,01X0,01TiO3 (X= Eu3+, Sm3+ ou Pr3+), que submetidas a diferentes tratamentos térmicos foram obtidas com níveis de ordem-desordem estrutural distintos. Os materiais sintetizados foram caracterizados por difração de raios X, confirmando a obtenção de um material homogêneo com estrutura perovsquita do tipo ortorrômbica. Essa caracterização permitiu ainda calcular o tamanho médio de cristalito das amostras, que varia em função do íon terra-rara presente. Os resultados da emissão fotoluminescente confirmaram a presença desse fenômeno óptico à temperatura ambiente e sua relação com o nível de ordem-desordem estrutural do sistema. A emissão fotoluminescente mais intensa ocorre nas amostras tratadas termicamente a 500 °C (independente do íon dopante), a variação do dopante influencia na intensidade da emissão devido à transferência de carga entre a matriz hospedeira e o íon terra-rara emissor, onde a amostra dopada com íon Pr3+ apresenta transferência de carga mais eficiente e consequentemente maior intensidade na emissão fotoluminescente. Outro fator que favorece a propriedade óptica das amostras é a compensação de carga, pois contribui para o aumento da desordem estrutural devido à formação de vacâncias do íon Ca2+.

Through the polymeric precursor method were synthesized samples Ca0.98Sr0.01X0.01TiO3 (X= Eu3+, Sm3+ and Pr3+), which under different heat treatments were obtained with levels of distinct structural order-disorder. The synthesized materials were characterized by X-ray diffraction, confirming the obtaining of ahomogeneous material with perovskite-type orthorhombic structure. This characterization allowed evaluating the average crystallite size of the samples that varies depending on the rare-earth ion. The results of photoluminescence emission confirmed the presence of this optical phenomenon at room temperature and its relationship to the level of order-disorder structural system. The photoluminescence emission is more intense in samples annealed at 500 ° C (independent on the dopant ion), the variation of the dopant influence on the emission intensity due to charge transfer between the host and emitting rare-earth ion, where the doped with Pr3+ ion has charge transfer more efficient and hence more intense emission in the photoluminescence. Another factor that favors the optical property of the samples is the charge compensation, as it contributes to the increase in structural disorder due to formation of Ca2+ vacancies.

This paper presents data for the synthesis and characterization of layer double hydroxides (LDH) and their use for color and chemical oxygen demand (COD) removal from effluents generated by a textile industry. Adsorption studies with raw and biologically treated (activated sludge) textile effluent showed that the pseudo-second order model best fitted the experimental data, leading to adsorption coefficients of 39.1 and 102.9 mgCOD/gLDH for raw and treated effluents, respectively. The best conditions for color and COD removal were obtained at lower values of temperature and pH (25 °C and pH 7) and, in these conditions, an LDH dose of 10 g/L resulted in color removal efficiencies of 56% for samples of raw and 66% for samples of treated effluent. Recycling studies indicated that the reuse of thermally treated LDH led to a progressive loss in the removal efficiencies of COD and color. The reduction was more pronounced with samples of the raw textile effluent. LDH characterization performed before and after each adsorption and regeneration experiment showed that there was no intercalation of dye molecules in the interlayer region of the LDH, indicating that COD and color removal might be due to the adsorption of organic molecules onto the LDH surface.