ABSTRACT Purpose: To evaluate the effect of the standardized laparoscopic simulation training program in pyeloplasty, following its implementation and during the COVID-19 pandemic. Material and Methods: A retrospective chart review was performed at Hospital de Clínicas de Porto Alegre, a tertiary referral center in south Brazil, in which 151 patients underwent laparoscopic pyeloplasty performed by residents between 2006-2021. They were divided into three groups: before and after adoption of a standardized laparoscopic simulation training program and during the COVID-19 pandemic. The main outcome was a combined negative outcome of conversion to open surgery, major postoperative complications (Clavien-Dindo III or higher) or unsuccessful procedure, defined as need for redo pyeloplasty. Results: There was a significant reduction in the combined negative outcome (21.1% vs 6.3%), surgical time (mean 200.0 min vs 177.4 min) and length of stay (median 5 days vs 3 days) after the adoption of simulation training program. These results were maintained during the COVID-19 pandemic (combined negative outcome of 6.3%, mean surgical time of 160.1 min and median length of stay of 3 days) despite a reduction in 55.4% of the surgical volume. Conclusion: A structured laparoscopic simulation program can improve outcomes of laparoscopic pyeloplasty during the learning curve.

Resumen La Altillanura es un ecosistema único de los Llanos colombianos, caracterizado por sabanas bien drenadas y grandes extensiones de bosques ribereños. La Altillanura alberga ricas comunidades poco estudiadas y actualmente amenazadas por la agroindustria a gran escala y no planificada. Además, el número de áreas protegidas públicas en la Altillanura no es suficiente para conservar los hábitats y especies amenazados. Por lo tanto, los esfuerzos de las reservas privadas son cruciales para la conservación de la biodiversidad de la región. Presentamos el primer listado de especies del Tomogrande, reserva natural privada y estación de investigación científica en el municipio de Santa Rosalía, Vichada, Colombia. Después de diez años de investigación en curso, hemos registrado 299 especies de plantas, 189 especies de aves y 47 especies de mamíferos. En comparación con otras reservas naturales privadas en Vichada y con el Parque Nacional Tuparro, el área protegida más grande de la región, Tomogrande hace una contribución sustancial a la conservación de los tres grupos taxonómicos. Abogamos por una mejor planificación del paisaje y que prácticas sostenibles sean obligatorias en la Altillanura, a fin de proteger su biodiversidad y los medios de vida de todos los actores que habitan esta región.

Abstract The Altillanura is a unique ecosystem within the Colombian Llanos, characterized by well-drained savannas and extensive riparian forests. The Altillanura harbors a rich assemblage of species, largely understudied and currently under threat by large-scale and unplanned agribusiness. Moreover, the number of public protected areas in the Colombian Llanos, particularly in the Altillanura, is insufficient to conserve the threatened habitats and species. Therefore, conservation efforts by private reserves are crucial for the protection of the region’s biodiversity. Here we present the first species list of the Tomogrande, a private nature reserve and scientific research field station in the municipality of Santa Rosalía, Vichada, Colombia. After ten years of ongoing research, we have recorded 299 species of plants, 189 species of birds, and 47 species of mammals. Compared to other private nature reserves in Vichada and the Tuparro National Park, the largest protected area in the region, Tomogrande makes a substantial contribution to the conservation of all three taxonomic groups. We advocate that better landscape planning and sustainable practices should become mandatory in the Altillanura to protect its biodiversity and the livelihoods of all stakeholders that inhabit this region.

Abstract: OBJECTIVE: To determine whether the association of the combination of serum concentrations of mean platelet volume and uric acid determined at 20 to 24 weeks of pregnancy are predictors of preeclampsia. MATERIALS AND METHODS: Case-control, retrospective, observational study consisting of the analysis of mean platelet volume and uric acid between 20 and 24 weeks of pregnancy. Study variables: age, body mass index greater than 25 kg/m2 (overweight and obesity), parity, family history of hypertension, exercise (more than 150 minutes per week), mean platelet and uric acid concentrations taken at 20 to 24 weeks of pregnancy, serum albumin, and spontaneous or assisted reproductive techniques pregnancy. The data were analyzed in the SPSS version 25 statistical package. RESULTS: A total of 122 cases and 199 controls were studied. According to the adjusted logistic regression model, we obtained an odds ratio (OR) for predicting preeclampsia of 4.383, with 95%CI: 1.980-9.705 for the elevation of mean platelet volume and an OR of 7.665 with 95%CI: 3.415-17.204 for the elevation of uric acid (p < 0.001). The other variables with statistical significance for risk of preeclampsia were: age, family history of arterial hypertension, conception by assisted reproduction techniques, multiple pregnancy, being primiparous and sedentary lifestyle. CONCLUSION: According to the results of this study, the increase in mean platelet volume (more than 9.7 fL) and uric acid (more than 4.9 mg/dL) between weeks 20 and 24 is a predictive biomarker of preeclampsia. Further studies are needed to confirm the validity and usefulness of these findings.

Resumen: OBJETIVO: Determinar si la asociación entre la combinación de las concentraciones séricas del volumen plaquetario medio y las del ácido úrico determinadas en las semanas 20 a 24 del embarazo son predictoras de preeclampsia. MATERIALES Y MÉTODOS: Estudio de casos y controles, retrospectivo y observacional consistente en el análisis del volumen plaquetario medio y de ácido úrico practicado entre las 20 a 24 semanas de embarazo. Variables de estudio: edad, índice de masa corporal mayor de 25 kg/m2 (sobrepeso y obesidad), paridad, antecedentes familiares de hipertensión arterial, realizar ejercicio (más de 150 minutos a la semana), valor plaquetario medio y concentraciones de ácido úrico tomados en las 20 a 24 semanas de embarazo, albúmina sérica y embarazo espontáneo o por técnicas de reproducción asistida. Los datos se analizaron en el paquete estadístico SPSS versión 25. RESULTADOS: Se estudiaron 122 casos y 199 controles. Conforme al modelo de regresión logística ajustado se obtuvo una razón de momios (RM) para predecir preeclampsia de 4.383, con IC95%: 1.980-9.705 para la elevación del volumen plaquetario medio y una RM de 7.665 con IC95%: 3.415-17.204 para la elevación del ácido úrico (p < 0.001). Las otras variables con relevancia estadística para riesgo de preeclampsia fueron: edad, antecedentes familiares de hipertensión arterial, concepción mediante técnicas de reproducción asistida, embarazo múltiple, ser primíparas y el sedentarismo como estilo de vida. CONCLUSIÓN: Conforme a los resultados de este estudio el aumento del volumen plaquetario medio (más de 9.7 fL) y del ácido úrico (más de 4.9 mg/dL) entre las semanas 20 a 24 es un biomarcador predictivo de preeclampsia. Hacen falta más estudios al respecto para confirmar la validez y utilidad de estos hallazgos.

RESUMO Este estudo tem como objetivo analisar e resumir as diferenças biomecânicas (cinéticas, cinemáticas e neuromusculares) da corrida com calçado e descalço através de uma revisão de literatura. Foram realizadas buscas por artigos completos publicados entre 2013 e novembro de 2018 nos bancos de dados Web of Science, PubMed, Scopus e SPORTDiscus. Os descritores usados foram Biomechanics, Kinetics, Kinematics, Electromyography, “Surface Electromyography”; e Unshod, Barefoot, Barefeet e Running. A busca resultou em 687 artigos, e depois da exclusão das duplicatas e seleção através do título, do resumo e do texto completo, 40 artigos foram incluídos na revisão. Os resultados evidenciam que existem diferenças importantes na biomecânica da corrida entre as condições calçado e descalço. De maneira geral, os estudos indicam que, na corrida descalço: (a) os indivíduos apresentam padrão de pisada com o antepé ou mesopé, enquanto na corrida com calçado, o padrão típico é com o retropé; (b) observa-se maior cadência e menor comprimento da passada; e (c) ocorre maior flexão de joelho, menor pico de força vertical de reação do solo e maior ativação da parte medial do gastrocnêmio. Ainda, na condição descalço, os corredores fazem o contato com o solo com maior flexão plantar, possivelmente buscando uma estratégia de atenuação de impacto durante a pisada sem calçado. Essas diferenças, assim como a individualidade dos praticantes, devem ser consideradas na prescrição da corrida descalço, visando minimizar a ocorrência de lesões decorrentes da prática. Nível de evidência II; Estudo de Revisão.

ABSTRACT This study aims to analyze and summarize the biomechanical (kinematics, kinetics and neuromuscular) differences between shod and barefoot running, through a literature review. Searches were conducted for complete articles published between 2013 and November 2018 in the Web of Science, PubMed, Scopus and SPORTdiscus databases. The search terms used were Biomechanics, Kinetics, Kinematics, Electromyography, “Surface Electromyography”; and Unshod, Barefoot, Barefeet and Running. The search resulted in 687 articles; after excluding duplicates and selecting by title, abstract and full text, 40 articles were included in the review. The results show that there are important differences in the biomechanics of running when shod or barefoot. In general, studies indicate that in barefoot running: a) individuals present forefoot or midfoot foot strike patterns, while in shod running the typical pattern is the rearfoot strike; (b) greater cadence and shorter stride length are observed; and (c) there is greater knee flexion, lower peak vertical ground reaction force and greater activation of the medial gastrocnemius. In addition, barefoot runners contact the ground with greater plantar flexion, possibly as a strategy to reduce impact when stepping without footwear. These differences, as well as runners’ individual characteristics, should be considered in the prescription of the barefoot running, in order to minimize injuries resulting from the practice. Level of Evidence II; Review.

RESUMEN Este estudio tiene como objetivo analizar y resumir las diferencias biomecánicas (cinéticas, cinemáticas y neuromusculares) de la carrera con calzado y descalzo a través de una revisión de literatura. Fueron realizadas búsquedas de artículos completos publicados entre 2013 y noviembre de 2018 en los bancos de datos Web of Science, PubMed, Scopus y SPORTDiscus. Los descriptores utilizados fueron Biomechanics, Kinetics, Kinematics, Electromyography, “Surface Electromyography”; y Unshod, Barefoot, Barefeet; y Running. La búsqueda resultó en 687 artículos, y después de la exclusión de los duplicados y selección a través del título, del resumen y del texto completo, 40 artículos fueron incluidos en la revisión. Los resultados evidencian que existen diferencias importantes en la biomecánica de la carrera entre las condiciones calzado y descalzo. De manera general, los estudios indican que, en la carrera descalzo: (a) los individuos presentan padrón de pisada con el antepié o mesopié, mientras que en la carrera con calzados, el padrón típico es con el retropié; (b) se observa mayor cadencia y menor longitud de la pasada; y (c) ocurre mayor flexión de la rodilla, menor pico de fuerza vertical de reacción del suelo y mayor activación de la parte medial del gastrocnemio. Además, en la condición descalzo, los corredores hacen el contacto con el suelo con mayor flexión plantar, posiblemente buscando una estrategia de atenuación de impacto durante la pisada sin calzado. Estas diferencias, así como la individualidad de los practicantes, deben ser consideradas en la prescripción de la carrera descalzo, buscando minimizar la ocurrencia de lesiones provenientes de la práctica. Nivel de Evidencia II; Estudio de Revisión.

Resumo As atividades de manejo florestal são consideradas importantes para o desenvolvimento sustentável no Brasil. Tais atividades, entretanto, exigem monitoramento rigoroso que muitas vezes é de difícil operacionalização. O mapeamento das áreas afetadas pela exploração seletiva de madeira e a mensuração dos impactos decorrentes da exploração florestal ainda são dependentes de extensos e onerosos levantamentos de campo. Neste estudo foi utilizada a tecnologia Light Detection and Ranging (LiDAR) aerotransportada para avaliação dos impactos causados pela extração seletiva de madeira em 21 Unidades de Produção Anual na Amazônia. As áreas de estudo estão localizadas nos estados de Rondônia e do Pará, dentro de Florestas Nacionais sob regime de concessão florestal federal. Foram utilizadas duas métricas derivadas da nuvem de pontos LiDAR para o mapeamento dos impactos nas florestas: a Canopy Height Model (CHM) como métrica do dossel e a Relative Density Model (RDM) como métrica do sub-bosque. Os resultados da detecção dos impactos florestais obtidos do mapeamento com dados do LiDAR são compatíveis com o levantamento realizado em campo. Estimou-se que as atividades de extração seletiva de madeiras impactaram em média 6,8% (± 1,3%, desvio padrão) da área total de sub-bosque das Unidades de Produção Anual (UPA) avaliadas e causaram incremento de 4,9% ± 0,9% em área de clareiras. A tecnologia LiDAR é efetiva para o monitoramento dos impactos da extração seletiva de madeiras em áreas sob concessão florestal federal na Amazônia.

Abstract Forest management activities are crucial for the sustainable development of Brazil. Those activities require, however, a strict monitoring that are often difficult to operationalize. The mapping of impacted areas by selective logging and the measurement of forest impacts because of logging operations are mostly based on extensive and costly field surveys. In this study, the Light Detection and Ranging (LiDAR) airborne technology was used to assess the impacts caused by selective logging within 21 units of forest annual production in the Amazon. The study sites are in the states of Rondônia and Pará, within National Forests under federal forestry concession. We used two metrics derived from the point cloud LiDAR for mapping forest impacts: The Canopy Height Model (CHM) and the Relative Density Model (RDM) as forest understory metric. The results of detection of forest impacts derived from the LiDAR dataset showed similar performance of field-based surveys. We estimated that selective logging activities had impacted an average of 6.8% (± 1.3%, standard deviation) of the forest understory of the Annual Production Units (APU) studied and caused an increase of 4.9% (± 0.9%) in areas of forest canopy opening. The LiDAR technology showed to be effective for assessing and monitoring forest impacts of selective logging in the federal forest concessions in the Amazon.

RESUMO Neste trabalho, compósito Fe2O3/grafite foi preparado e usado como um catalisador em reação foto-Fenton para a descoloração de solução aquosa contendo o corante amaranto sob irradiação de luz visível. Amostras com diferentes teores de Fe2O3 suportados sobre grafite foram preparadas e caracterizadas por difração de raios-X (DRX), adsorção-dessorção de N2 e microscopia eletrônica de varredura (MEV). O aumento do teor de ferro nos compósitos resultou em uma superior área de superfície específica. Através da metodologia de superfície de respostas gerada a partir do Delineamento Composto Central Rotacional (DCCR), verificou-se uma eficiência máxima de descoloração da solução de corante de 93% nas condições experimentais ótimas de reação foto-Fenton (pH = 2,5, quantidade de catalisador = 0,35 g L-1 e razão molar H2O2/Ʃ elementos mineralizáveis: 4,7). Portanto, o compósito Fe2O3/grafite pode ser utilizado como um potencial catalisador foto-Fenton para a degradação do corante amaranto em efluentes líquidos.

ABSTRACT In this work, Fe2O3/graphite composite was prepared and used as a catalyst in photo-Fenton reaction for the decolorization of amaranth dye from aqueous solution under visible light irradiation. Samples with different Fe2O3 contents supported on graphite were prepared and characterized by X-ray diffraction (XRD), N2 adsorption-desorption and scanning electron microscopy (SEM). The increase of the iron content in the composites resulted in a superior specific surface area. The response surface methodology generated from the Rotational Central Composite Design (RCCD) showed a maximum efficiency in the decolorization of the dye solution of 93% under the optimal experimental conditions of photo-Fenton reaction (pH = 2.5, amount of catalyst = 0.35 g L-1 and molar ratio H2O2/Ʃ mineralizable compounds: 4.7). Therefore, the Fe2O3/graphite composite can be used as a potential photo-Fenton catalyst for the degradation of amaranth dye from liquid effluents.

RESUMO Neste trabalho, ferrita de cobalto (CoFe2O4) foi sintetizada sobre aluminato de magnésio (MgAl2O4) e zeólita ZSM-5 e a atividade catalítica desses materiais na reação foto-Fenton visando a decomposição de um poluente orgânico em solução aquosa foi avaliada. Ferrita de cobalto foi sintetizada sobre os suportes pela rota solvotérmica. Os materiais magnéticos foram caracterizados por difração de raios-X, isotermas de adsorção/dessorção de nitrogênio, microscopia eletrônica de varredura e espectroscopia de energia dispersiva de raios-X. Os catalisadores foram avaliados na degradação de corante amaranto sob irradiações visível artificial e solar. Os sistemas produzidos CoFe2O4/MgAl2O4 e CoFe2O4/ZSM-5 apresentaram satisfatórias atividades catalíticas, sendo superior comparado a ferrita de cobalto pura. As atividades catalíticas para ambos os sistemas foram superiores quando do uso de irradiação solar, atingindo 95 % de descoloração e 80 % de mineralização em 30 e 240 min de reação, respectivamente. Portanto, MgAl2O4 e ZSM-5 como suportes para a ferrita de cobalto apresentam-se como materiais promissores para a degradação de poluentes orgânicos em soluções aquosas através da reação foto-Fenton heterogênea.

ABSTRACT In this work, cobalt ferrite (CoFe2O4) was synthesized on magnesium aluminate (MgAl2O4) and ZSM-5 zeolite and the catalytic activity of these materials in the photo-Fenton reaction for the decomposition of an organic pollutant in aqueous solution was evaluated. Cobalt ferrite was synthesized on the supports by the solvothermal route. The magnetic materials were characterized by X-ray diffraction, adsorption/desorption isotherms of nitrogen, scanning electron microscopy and X-ray dispersive energy spectroscopy. The catalysts were evaluated for the degradation of amaranth dye under artificial visible and solar irradiations. The produced materials CoFe2O4/MgAl2O4 and CoFe2O4/ZSM-5 presented satisfactory catalytic activities, being superior compared to pure cobalt ferrite. Both the systems showed higher catalytic activity when solar irradiation was used, reaching 95% of decoloration and 80% of mineralization at 30 and 240 min of reaction, respectively. Therefore, MgAl2O4 and ZSM-5 as supports for the cobalt ferrite are promising materials aiming the degradation of organic pollutants in aqueous solutions through the heterogeneous photo-Fenton reaction.

In this work, cobalt ferrite (CoFe2O4) was synthesized by solvothermal route for application as a catalyst in the ozonation reaction for the decolorization and mineralization of melanoidin from aqueous solution. The structural properties of CoFe2O4 sample were investigated by X-ray diffraction (XRD), nitrogen adsorption-desorption isotherms, Fourier-transform infrared spectroscopy (FTIR), particle-size distribution, scanning electron microscopy (SEM) and X-ray dispersive energy spectroscopy (EDS). Single-phase CoFe2O4 particles with a predominantly mesoporous structure containing a high specific surface area were obtained. Results showed that the CoFe2O4-catalyzed ozonation reaction has higher activity for the decolorization and mineralization of melanoidin when compared with the ozonation reaction without the presence of catalyst. Therefore, this material can be very promising for the application in catalytic ozonation systems for the melanoidin removal from liquid effluents.

Resumo Neste trabalho, zeólita ZSM-5 mesoestruturada foi preparada usando quitina como um novo auxiliar de síntese para produzir mesoporosidade. Foram utilizadas diferentes quantidades de quitina para a síntese de ZSM-5, a fim de verificar a sua influência na formação de mesoporos. Todas as amostras foram preparadas por processo hidrotérmico convencional. Para fins de comparação, a zeólita ZSM-5 também foi sintetizada sem a presença de quitina. As amostras foram caracterizadas por difração de raios X, microscopia eletrônica de varredura e isotermas de adsorção-dessorção de N2. Os resultados experimentais mostraram que o volume de mesoporos das amostras obtidas aumentou com a quantidade crescente de quitina na mistura reacional. Portanto, a quitina mostrou ser um auxiliar de síntese promissor para a obtenção da ZSM-5 com propriedade mesoporosa.

Abstract In this work, mesostructured ZSM-5 zeolite was prepared using chitin as a new template to produce mesoporosity. Different amounts of chitin were used for the synthesis of ZSM-5 in order to verify its influence on the formation of mesopores. All samples were prepared by conventional hydrothermal process. For comparison purposes, ZSM-5 zeolite has also been synthesized without a presence of chitin. The samples were characterized by X-ray diffraction, scanning electron microscopy and N2 adsorption techniques. Experimental results showed that the mesopores volume of the obtained samples increased with increasing amount of chitin in the reaction mixture. Therefore, chitin showed to be a promising template for obtaining the ZSM-5 with mesoporous property.

ABSTRACT Introduction After the diagnosis of transsexualism is confirmed therapy commences with psychotherapeutic preparation for the conversion, and after conversion, long-term patient rehabilitation is maintained for at least two years. The indication for surgery is chronic discomfort caused by discord with the patient's natural gender, intense dislike of developing secondary sex characteristics and the onset of puberty. The surgical conversion of transsexuals is the main step in the complex care of these problematic patients (1). This surgery was first described by Benjamin H, using a flap of inverted penile skin (2) and is considered the gold standard since then. Male-to-female transsexual surgical techniques are well defined and give good cosmetic and functional results. Sex reassignment surgery promotes the improvement of psychological aspects and social relationships as shown in the World Health Organization Quality of Life Assessment applied in the patients submitted to this procedure (3). Techniques include the creation of a normal appearing female introitus, a vaginoplasty allowing sexual intercourse and the capability of clitoral orgasm (4). Various methods for neovaginoplasty have been described and can be classified into five categories, i.e. pedicled intestinal transplants, penile skin grafts, penile skin flaps, non-genital skin flaps and non-genital skin grafts (5). In our Hospital, we use penile and scrotal skin flaps. Until now, 174 procedures have been performed by our team using this technique with high rates of satisfaction (3). Patients and methods We present a step-by-step male to female transsexual surgery. Conclusion Surgical gender reassignment of male transsexuals resulted in replicas of female genitalia which enabled coitus with orgasm (1). With this video we show step by step that a surgery using penile skin flaps is able to be performed with good cosmetic results.

Abstract We reviewed the occurrences and distributional patterns of migratory species of birds in Brazil. A species was classified as migratory when at least part of its population performs cyclical, seasonal movements with high fidelity to its breeding grounds. Of the 1,919 species of birds recorded in Brazil, 198 (10.3%) are migratory. Of these, 127 (64%) were classified as Migratory and 71 (36%) as Partially Migratory. A few species (83; 4.3%) were classified as Vagrant and eight (0,4%) species could not be defined due to limited information available, or due to conflicting data.

RESUMEN. Transferir preferencias sobre candidatos a preferencias sobre conjuntos de candidatos permite dar una noción muy natural de manipulación para funciones de elección social. En este trabajo damos condiciones sobre esas funciones de transferencia que implican la manipulabilidad de funciones de elección social con un mínimo de propiedades razonables. Nuestro resultado es una versión débil del teorema de Barbera y Kelly, de hecho puede ser obtenido como una consecuencia de Éste. Sin embargo, damos una prueba directa y natural de nuestro teorema de manipulabilidad, la cual da una información clara sobre la naturaleza de las funciones de transferencia que permiten la manipulación.

ABSTRACT. Lifting preferences over candidates to preferences over sets of candidates allows us to give a very natural notion of manipulability for social choice functions. In particular, we give simple conditions over the liftings entailing the manipulability of reasonable social choice functions. Our result is a weak version of Barbera and Kelly's Theorem, indeed it can be obtained from this last Theorem. However, we give a direct and very natural proof of our manipulability Theorem which is informative about the nature of the liftings allowing manipulability.

ABSTRACT Introduction: Ganglioneuromas are rare benign neoplasms of the sympathetic nervous system. We describe the case of an incidentally found ganglioneuroma in a woman. To our knowledge this is the first described case of robotic excision of a retroperitoneal ganglioneuroma. Case: A 41-year-old female had an incidental retroperitoneal mass found during a routine US. CT scan and MRI showed an 8.3cm homogeneous mass, adjacent to left kidney upper pole, with peripheral contrast enhancement. Metabolic tests were normal. Patient was positioned in a left flank position and five ports were introduced transperitoneally. A 4-arm Da Vinci SI was docked at a 45° angle to the table. Lesion was dissected along with left adrenal gland, beginning at the left renal hilum and proceeding cephalad. Results: Operating time was 325min and blood loss was 50ml. Patient was discharged after 72hours. There were no postoperative complications. Pathology showed ganglionic cells with neural tissue, and normal adrenal. Discussion: Ganglioneuromas rare benign tumors originating from neural crest and typically affect young adults. Most frequent locations are posterior mediastinum, retroperitoneum and adrenal gland. As in this case, ganglioneuromas are usually silent, slow growing tumors discovered incidentally or by mass effect. US and CT imaging may suggest the diagnosis while MRI findings can be specific for ganglioneuroma. Percutaneous biopsy is an option. Although benign, usually requires surgical excision for treatment. Conclusions: Our case shows that a robotic approach is feasible and allows for meticulous and safe dissection of vascular structures, facilitating adequate hemostasis while maintaining oncological principles.

This study investigated the potential of Brazilian kaolin as a low-cost adsorbent for the removal of Malachite Green (MG) from colored effluents. The morphology, chemical structure and surface properties of the adsorbent were investigated by characterization techniques such as X-ray diffraction, N2 adsorption-desorption isotherms, Fourier transform infrared spectroscopy, X-ray fluorescence spectrometry, scanning electron microscopy, thermogravimetric analysis and particle size distribution. A possible technological application of raw kaolin is the MG removal from aqueous media, which was investigated using batch adsorption experiments. The adsorption kinetics was studied using the pseudo-first order, pseudo-second order and Elovich models. The adsorption isotherms were studied using the Langmuir, Freundlich and Sips models. The Elovich model was the more adequate to represent the adsorption kinetic, while the equilibrium was well represented by the Langmuir model. The maximum adsorption capacity, at pH of 6.3 and temperature of 25ºC, was 128 mg g-1, and this satisfactory result may be associated with some adsorbent properties. Therefore, the results revealed that raw kaolin can be utilized as a promising low-cost adsorbent to remove MG from colored effluents.

Nickel ferrite/multi-walled carbon nanotubes (NiFe2O4/MWCNTs) composite has been rapidly synthesized via microwave irradiation technique. The structural properties of the product was investigated by X-ray diffraction (XRD), N2 adsorption/desorption isotherms, thermogravimetric analysis (TGA), Raman spectroscopy and, scanning electron microscopy (SEM). Catalytic behavior of the composite material on the advanced photo-Fenton degradation of Amaranth dye was evaluated. The synthesis conditions employed on the microwave system were: temperature (235 °C), power (500 W), pressure (600 psi) and irradiation time (30 min). Characterization results showed the formation of hybrid material, containing a predominantly microporous structure, with surface area and total pore volume of 54 m2 g-1 and 0.2249 cm3 g-1, respectively. The composite exhibited higher catalytic activity compared to the pure NiFe2O4, reaching 100% of decolorization at 60 min of reaction, which can be attributed to a synergism between NiFe2O4 and MWCNTs. Therefore, NiFe2O4/MWCNTs composite can be used as a promising photo-Fenton catalyst to degrade Amaranth dye from aqueous solutions.