340 results on '"Carla Garcia"'
Search Results
302. Frizzled7 mediates canonical Wnt signaling in neural crest induction
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Grant N. Wheeler, Muhammad Abu-Elmagd, and Carla Garcia-Morales
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Frizzled ,medicine.medical_specialty ,Embryo, Nonmammalian ,animal structures ,Xenopus ,Molecular Sequence Data ,Ectoderm ,Xenopus Proteins ,Biology ,Receptors, G-Protein-Coupled ,Xenopus laevis ,Neural crest ,Wnt ,Noggin ,Internal medicine ,medicine ,Paraxial mesoderm ,Animals ,BMP ,Molecular Biology ,Body Patterning ,Neural fold ,Base Sequence ,Neural tube ,Wnt signaling pathway ,Cell Biology ,Slug ,Cell biology ,Xfz7 ,Wnt Proteins ,Endocrinology ,medicine.anatomical_structure ,embryonic structures ,Neural plate ,Signal Transduction ,Developmental Biology - Abstract
The neural crest is a multipotent cell population that migrates from the dorsal edge of the neural tube to various parts of the embryo where it differentiates into a remarkable variety of different cell types. Initial induction of neural crest is mediated by a combination of BMP, Wnt, FGF, Retinoic acid and Notch/Delta signaling. The two-signal model for neural crest induction suggests that BMP signaling induces the competence to become neural crest. The second signal involves Wnt acting through the canonical pathway and leads to expression of neural crest markers such as slug. Wnt signals from the neural plate, non-neural ectoderm and paraxial mesoderm have all been suggested to play a role in neural crest induction. We show that Xenopus frizzled7 (Xfz7) is expressed in the dorsal ectoderm including early neural crest progenitors and is a key mediator of the Wnt inductive signal. We demonstrate that Xfz7 expression is induced in response to a BMP antagonist, noggin, and that Xfz7 can induce neural crest specific genes in noggin-treated ectodermal explants (animal caps). Morpholino-mediated or dominant negative inhibition of Xfz7 inhibits Wnt induced Xslug expression in the animal cap assay and in the whole embryo leading to a loss of neural crest derived pigment cells. Full-length Xfz7 rescues the morpholino-induced phenotype, as does activated β-catenin, suggesting that Xfz7 is signaling through the canonical pathway. We therefore demonstrate that Xfz7 is regulated by BMP antagonism and is required for neural crest induction by Wnt in the developing vertebrate embryo.
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303. Visión del Nuevo Orden Internacional en el Siglo XXI
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Nelson García-Osorio, Carla García Moreta, and Celio Guayasamín-Segovia
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Estados Unidos ,Rusia ,China ,Hegemonía ,Commerce ,HF1-6182 ,Finance ,HG1-9999 - Abstract
El presente trabajo tiene como objetivo desentrañar el cambio en el liderazgo mundial basado en la expansión financiera y petrolera. La sucesión de ciclos de acumulación económica dirigidos por Gran Bretaña en el siglo XIX y Estados Unidos de Norte América en el Siglo XX, estas situaciones hegemónicas no suspenden los procesos de competencia, centralización del capital y del poder, responsables de la repetición periódica de grandes crisis y largos períodos de transición, reorganización de la base productiva así como de cambio en el liderazgo mundial del sistema, por el resurgimiento económico de China que ha llevado a un nuevo nivel, la discusión entre el proceso de formación de una economía de mercado, el desarrollo capitalista y la reemergencia geopolítica de Rusia la cual es considerada por Estados Unidos una amenaza dada su capacidad nuclear y energética.
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- 2017
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304. El uso de las TIC y herramientas de la Web 2.0 por maestros portugueses de la educación primaria y educación especial: la importancia de las competencias personales
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Carla García, Paulo Días, Antonio Sorte, Julian Díaz Pérez, Ana Rita Leal, and Mario Gandra
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Education ,Theory and practice of education ,LB5-3640 - Abstract
Este estudio tiene como objetivo analizar el papel de las habilidades personales como las actitudes y autoeficacia en relación con el uso de las Tecnologías de la Información y la Comunicación (TIC) y las herramientas Web 2.0 entre los maestros de la Enseñanza Regular y Educación Especial. Se utilizó una metodología cuantitativa en una muestra de 200 maestros de Primaria y Educación Especial. Se administró un cuestionario sobre el uso de las TIC y las herramientas de la Web 2.0, una Escala de Autoeficacia hacia el Uso del Ordenador, una Escala de las Actitudes hacia la Informática en Educación y una Escala sobre el Uso del Ordenador en Aula. Los resultados sugieren que la mayoría de los maestros utilizan las TIC en sus tareas personales y profesionales diarias, así como herramientas de la Web 2.0, siendo la más frecuente la de YouTube y los Blogs de los maestros de Educación Primaria y los programas educativos para los maestros de Educación Especial. Estudios inferenciales nos permiten verificar las diferencias en las actitudes y autoeficacia en función de variables personales y profesionales. Se analizaron los resultados obtenidos y las implicaciones para la formación docente y se presentaron sugerencias para estudios posteriores.
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- 2014
305. Reusing Treated Waste-Water from a Circular Economy Perspective—The Case of the Real Acequia de Moncada in Valencia (Spain)
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Joep Hagenvoort, Mar Ortega-Reig, Salut Botella, Carla García, Ana de Luis, and Guillermo Palau-Salvador
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recycle water ,reuse ,traditional irrigation ,surface irrigation ,water quality ,East Spain ,Hydraulic engineering ,TC1-978 ,Water supply for domestic and industrial purposes ,TD201-500 - Abstract
One of the most important challenges that agriculture faces is sustainable water management and its adaptation to climate change. This adaptation is more important in regions where recurrent draughts and overexploitation of water resources happen. However, historical irrigation systems, such as the Real Acequia de Moncada (RAM) in Valencia, have found innovative approaches to deal with this phenomenon. This paper analyzes the case of Massamagrell and Puçol, which reused the treated waste-water of the closest waste-water treatment plant (WWTP). The study focused from a circular economy perspective on the technological, agronomical, and social implications of this decision. Results show that there are clear benefits for both farmers and WWTP managers. On the one hand, additional nutrients and regularity in their water supply benefit farmers. On the other, WWTP managers can reuse the treated effluent in the system, contributing to the closure of the water cycle and avoiding pumping the treated water into the sea. However, more detailed information and coordination is needed among the different stakeholders. Questions regarding the illegal connection of waste pipes with the traditional irrigation or the payment of pumping costs for reuse have gone unanswered, and there is a need for better reflection from all stakeholders.
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- 2019
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306. Historia del arte y universidad. Momentos clave en la Facultad de Filosofía y Letras de la UBA (1915-1986)
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Carla García and Ana Schwartzman
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Universidad de Buenos Aires ,historia del arte ,programas de estudio ,Julio Payró ,History of the arts ,NX440-632 ,Visual arts ,N1-9211 - Abstract
Este artículo recupera los recorridos cardinales de la historia del arte en la Facultad de Filosofía y Letras de la Universidad de Buenos Aires, considerando el período previo a la creación de la carrera específica en el año 1963 y las posteriores instancias de cambios y reajustes de contenidos en relación a contextos políticos concretos e influjos de figuras emergentes. Nuestra principal documentación la constituyen los programas de estudio, que permiten conocer los procesos de selección y abordaje metodológico de los contenidos y temas en el ámbito académico, y señalar los supuestos conceptuales que rigieron en la concepción de la disciplina Historia del Arte desde la Universidad.
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- 2015
307. Variación intraespecífica e individual de los pelos de mamíferos del Estado de México: implicaciones en la identificación interespecífica
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Octavio Monroy-Vilchis, Carla García-Morales, Ricardo Rubio-Rodríguez, Anuar David Hernández-Saint Martín, Juan Pablo Medina-Castro, Ulises Aguilera-Reyes, and Andrea I. Ortiz-García
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pelo ,médula ,identificación ,mamíferos ,estado de méxico ,Science ,Social Sciences - Abstract
Se determinó la variación del pelo de guardia dorsal entre individuos de la misma especie y se comparó la variación de un individuo en diferentes regiones. Se midió la longitud total y diámetro de la médula, además se determinó el patrón de tonalidad y tipo de médula. En la comparación intraespecífica se caracterizaron 530 pelos de guardia dorsales de 53 organismos. A pesar de las variaciones en la longitud y diámetro de la médula, puede realizarse una identificación exitosa de los organismos en un plano específico utilizando la guía de identificación de mamíferos terrestres a partir del pelo de guardia, excepto para Canis latrans y Liomys irroratus. En la comparación individual se describieron 560 pelos de guardia de 14 especies. Se encontraron diferencias en la longitud total del pelo, en el diámetro de la médula y en la coloración; el único carácter que permaneció constante fue la médula.
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- 2005
308. Comunicar y visibilizar: migrantes y Derechos Humanos
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Adriana Archenti, Orlando Gabriel Morales, and Carla García
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Communication. Mass media ,P87-96 ,Social sciences (General) ,H1-99 - Abstract
En el presente artículo desarrollaremos el proceso de gestación, la implementación y algunos resultados y reflexiones surgidas a partir de la implementación del proyecto de extensión universitaria: "Otros en Red. Producción, publicación y distribución de contenidos informativos para la comunicación intercultural entre distintos colectivos migrantes y entre éstos y la sociedad mayor en Argentina", acreditado y subsidiado por la UNLP en 2007. La propuesta fue ejecutada desde el Centro de Estudios Aplicados sobre Migraciones, Comunicación y Relaciones Interculturales (CEAMCRI) de la Facultad de Periodismo y Comunicación Social de la UNLP y tuvo como destinatarios directos a migrantes en forma individual, así como organizaciones comunitarias, asociaciones de inmigrantes y otros actores institucionales, para quienes se pone a disposición el medio de difusión y comunicación intercultural www.otrosenred.com.ar, así como los demás servicios brindados en el marco del desarrollo del presente proyecto. Miembros de colectivos migrantes y de la sociedad mayor, a partir de su capacitación para la producción de material informativo y la posibilidad de su incorporación efectiva al centro de producción de información. Palabras clave: Migrantes- comunicación- interculturalidad- extensión
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- 2012
309. Prevalence of Cryptococcal Antigenemia and Lateral Flow Assay Accuracy in Severely Immunosuppressed AIDS Patients
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Adriana Carla Garcia Negri, Maína de Oliveira Nunes, Gláucia Moreira Espíndola Lima, James Venturini, Sandra Maria do Valle Leone de Oliveira, Márcia dos Santos Lazera, Lídia Raquel de Carvalho, Marilene Rodrigues Chang, Rosianne Assis de Sousa Tsujisaki, Adriana de Oliveira França, Rinaldo Poncio Mendes, and Anamaria Mello Miranda Paniago
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cryptococcosis ,HIV infection ,immunocromatography ,point-of-care systems ,Biology (General) ,QH301-705.5 - Abstract
This study aimed to estimate the prevalence of cryptococcal antigenemia detected by lateral flow assay (LFA) in AIDS patients and its accuracy in the diagnosis of cryptococcosis. Conducted at a university hospital in Brazil from March 2015 to July 2017, it included AIDS patients over 18 years old with a CD4+ count ≤ 200 cells/mm3. Cryptococcal antigen (CrAg) detection using LFA and latex agglutination (LA), along with blood and urine cultures, were performed. The reference standard was the identification of Cryptococcus spp. in clinical specimens through microbiological or histopathological examination. Among 230 patients, the prevalence of CrAg detected by LFA (CrAg LFA) was 13.0%. Factors associated with cryptococcal antigenemia included fever, vomiting, seizures, and a lack of antiretroviral therapy. The sensitivity and specificity of CrAg LFA were 83.9% and 98.0%, respectively. The positive predictive value (PPV) was 86.7%, the negative predictive value (NPV) was 97.5%, and overall accuracy was 96.1%. Cross-reactions were observed in patients with histoplasmosis and paracoccidioidmycosis, but not with aspergillosis or positive rheumatoid factor. The study concludes that the LFA is a useful tool for detecting cryptococcal antigenemia in severely immunocompromised AIDS patients due to its high NPV, specificity, and PPV.
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- 2024
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310. Effects of Al3+ concentration on the optical, structural, photocatalytic and cytotoxic properties of Al-doped ZnO.
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Andrade, Jessica de Lara, Oliveira, Angelica Gonçalves, Moraes, Juliana Carla Garcia, Hechenleitner, Ana Adelina Winkler, Pineda, Edgardo Alfonso Gomez, de Oliveira, Daniela Martins Fernandes, Mariucci, Vinícius Vaulei Gonçalves, Bento, Antonio Carlos, Companhoni, Mychelle Vianna, Nakamura, Celso Vataru, Lima, Sandro Marcio, and Andrade, Luis Humberto da Cunha
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NANOSTRUCTURED materials , *SOL-gel processes , *NANOPARTICLES , *ZINC oxide , *X-ray diffraction - Abstract
ZnO-Al x% nanoparticles (NPs), with x = 0, 1, 3, 5 or 10 mol% Al 3+ , were synthesized by a modified sol-gel method. The effects of Al 3+ content on the structure, morphology and optical properties of Al-doped ZnO were investigated by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, photoacoustic absorption spectroscopy (PAS), photoluminescence spectroscopy (PL) and specific surface area determination. A single crystalline phase characteristic of ZnO with wurtzite structure was detected for all synthesized oxides. With increasing dopant content, the average crystallite size of the NPs decreased from 25 to 7 nm. ZnO-Al x% NPs exhibited enhanced optical properties with the absorption slightly shifted to the visible region and with the band gap energy (E g ) decreased from 3.12 (undoped ZnO) to 2.95 eV (ZnO-Al 3%). Undoped ZnO showed intense PL above 430 nm, which was considerably decreased with the insertion of Al 3+ . Despite the increase of the surface area with Al 3+ doping of ZnO NPs, its catalytic activity in the decomposition reaction of Congo red showed a decrease with doping. Research has shown that ZnO NPs can selectively target and kill cancer cells and that its cytotoxicity is dependent of the concentration. The doping can be a method of shape the cytotoxicity of ZnO NPs and their optical and photocatalytic properties. In-vitro cytotoxicity studies showed that both undoped ZnO and Al-doped ZnO NPs synthesized were highly cytotoxic for fibroblast cells, suggesting that these nanomaterials could be promising anticancer agents. [ABSTRACT FROM AUTHOR]
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- 2017
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311. … y ahora, también ingresamos a Scopus®
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Enrique Leo Portiansky, Gastón Moré, Julio Roberto Idiart, María Carla Garcia Mitacek, Cecilia Mónica Galosi, Germán Ernesto Metz, and Andrea Dellarupe
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Animal culture ,SF1-1100 ,Veterinary medicine ,SF600-1100 - Abstract
El año 2023 ha llegado con buenas noticias para Analecta Veterinaria. Nuestra revista de difusión científica ha logrado ingresar al listado de obras indizadas por Scopus, una base de datos de resúmenes y citas de literatura revisada por pares, que incluye revistas científicas, libros y actas de congresos. Scopus proporciona una visión general completa de la producción de investigación en todo el mundo en los campos de la ciencia, la tecnología, la medicina, las ciencias sociales, las artes y las ciencias humanas. Además, identifica autores, y brinda acceso a datos, métricas y herramientas analíticas. Esta prestigiosa base de datos brinda un perfil de autor, que es un registro único (con un número identificador propio) de la actividad de publicación de ese investigador. Los detalles provienen de artículos revisados por pares y otras publicaciones que están indizadas en el sitio. La información en un perfil incluye el nombre del autor, filiación(es), área(s) temática(s), publicaciones, citas y coautores. Estos datos garantizan que la actividad de investigación publicada de un autor sea visible para otros investigadores. Entre los datos estadísticos, Scopus aporta el conocido factor o índice-H, que es un índice que cuantifica los resultados de la investigación científica de un individuo. Este índice se basa en el mayor número de artículos incluidos que han tenido al menos el mismo número de citas. El ingreso de Analecta Veterinaria al listado de revistas indizadas por Scopus®, permitirá incrementar el índice-H a todos los autores de la revista que sean citados por cualquier otro trabajo científico publicado en otras revistas del listado, que incluye más de 25000 títulos provenientes de diferentes editoriales (Elsevier, Springer, y Wiley-Blackwell, entre otras). Cabe destacar que el estar incluido en Scopus tiene la ventaja adicional de que todos sus datos son tomados por otra base de datos: ScimagoJournal& Country Rank (SJR). El SJR es un portal público que incluye las revistas e indicadores científicos. Estos indicadores se pueden utilizar para evaluar y analizar dominios científicos. El índice de rango de SJR es una medida del impacto de la revista, su influencia y prestigio. Expresa el promedio de citas ponderadas recibidas en el año seleccionado, por los documentos publicados en la revista en los tres años previos. Esta ponderación se realiza por cuartiles. Ambas bases de datos, Scopusy SJR, son tomados como referencia por CONICET, tanto a la hora de otorgar becas, ingresar a la carrera del investigador científico y tecnológico o promover de categoría. Por esta razón, todos aquellos investigadores que tengan la pretensión de ser evaluados en alguna instancia de las mencionadas deberían tomar en consideración estas bases de datos. Analecta Veterinaria viene en franca expansión en cuanto a su alcance internacional, inicialmente a través del Núcleo Básico de Revistas de CAICYT (http://caicyt-conicet.gov.ar/sitio/analecta-veterinaria/) y Latindex (Sistema Regional de Información en Línea para Revistas Científicas de América Latina, el Caribe, España y Portugal) (https://latindex.org/latindex/ficha/23959) y más recientemente en SciELO (http://www.scielo.org.ar/scielo.php?script=sci_serial&pid=1514-2590&lng=es&nrm=iso). Con el ingreso de Analecta Veterinaria a Scopus® (https://www.scopus.com/) y SJR (https://www.scimagojr.com/index.php) hemos dado un gran salto hacia la internacionalización de nuestras ciencias veterinarias.
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- 2023
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312. Effective and Low-Maintenance IMTA System as Effluent Treatment Unit for Promoting Sustainability in Coastal Aquaculture
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Luís Resende, Juan Flores, Cláudia Moreira, Diana Pacheco, Alexandra Baeta, Ana Carla Garcia, and Ana Cristina Silva Rocha
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estuary ,macroalgae ,effluent ,bioremediation ,aquaculture ,sustainability ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Integrated multitrophic aquaculture (IMTA) is a versatile technology emerging as an ecological and sustainable solution for traditional monoculture aquacultures in terms of effluent treatment. Nevertheless, IMTA is still poorly applied in aquaculture industry due to, among other reasons, the lack of effective, low-investment and low-maintenance solutions. In this study, one has developed a practical and low maintenance IMTA-pilot system, settled in a semi-intensive coastal aquaculture. The optimisation and performance of the system was validated using Ulva spp., a macroalgae that naturally grows in the fishponds of the local aquaculture. Several cultivation experiments were performed at lab-scale and in the IMTA-pilot system, in static mode. The specific growth rate (SGR), yield, nutrient removal, N and C enrichment, protein and pigment content were monitored. Ulva spp. successfully thrived in effluent from the fish species sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) production tanks and significantly reduced inorganic nutrient load in the effluent, particularly, NH4+, PO43− and NO3−. The enrichment of nitrogen in Ulva spp.’s tissues indicated nitrogen assimilation by the algae, though, the cultivated Ulva spp. showed lower amounts of protein and pigments in comparison to the wild type. This study indicates that the designed IMTA-pilot system is an efficient solution for fish effluent treatment and Ulva spp., a suitable effluent remediator.
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- 2021
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313. Acute Flaccid Myelitis Among Hospitalized Children in Texas, 2016.
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Downey, Rachel, McElvain, Dawn, Murphey, Donald K., Bailey, Ann, Patel, Bhairav, Fernandez, Marisol, Loftis, Laura, Carreno, Carla Garcia, Eger, Lynne, Aguilera, Elizabeth A., Wootton, Susan, Castagnini, Luis A., Hauger, Sarmistha B., Garcia Carreno, Carla, Aguilera, Elizabeth, and Castagnini, Luis
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HOSPITAL care of children , *MYELITIS , *ACTIVITIES of daily living , *METROPOLITAN areas , *THERAPEUTICS , *SPINAL cord , *RESEARCH , *NEUROMUSCULAR diseases , *CENTRAL nervous system viral diseases , *RESEARCH methodology , *RETROSPECTIVE studies , *MEDICAL cooperation , *EVALUATION research , *COMPARATIVE studies , *RESEARCH funding , *ENTEROVIRUS diseases , *LONGITUDINAL method , *DISEASE complications - Abstract
Background: Acute flaccid myelitis is characterized by acute-onset flaccid limb weakness with predominantly gray matter lesions in the spinal cord spanning one or more segments. Rates of full recovery are poor, and there is no standard treatment or definitive cause.Methods: This is a retrospective review of children diagnosed with acute flaccid myelitis in Texas during 2016. Patients were identified through a Texas collaborative of six hospitals in four major metropolitan areas. Data abstraction included health history, illness presentation, medical treatments, laboratory studies, imaging data, recovery, and ability to perform activities of daily living up to approximately two years from illness onset.Results: Among all sites, 21 patients met inclusion criteria. Treatments varied with the most common being intravenous immunoglobulin, high-dose methylprednisolone, and plasmapheresis. No differences were seen in response to medical treatments. A potential etiology was found in 12 (57%) cases, including four with enterovirus D68. Five cases recovered fully. Of the 16 patients without full recovery, abilities ranged from (1) able to perform all activities of daily living for age independently (n = 5), (2) mild deficits (n = 5), and (3) substantial reliance on caregivers for activities of daily living (n = 6).Conclusion: Many reports describe symptoms and outcomes of acute flaccid myelitis, but limited data are available on long-term functional outcomes. We were unable to make a strong case for any single cause or treatment modality. Fortunately, the majority of patients (15, 71%) were able to perform activities of daily living with complete independence or only mild deficits. [ABSTRACT FROM AUTHOR]- Published
- 2020
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314. Utilização de resíduo vegetal do chuchu (Sechium edule SW.) como coagulante natural para tratamento de efluentes têxteis
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Almeida, Cibele Andrade de, Juliana Carla Garcia Moraes [Orientador] - UEM, Prof.ª Dr.ª Juliana Carla Garcia Moraes, Vitor de Cinque Almeida - UEM, and Elton Guntendorfer Bonafe - UTFPR
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Sechium edule SW ,Coagulante natural ,Efluentes têxteis ,Coagulação ,Química ,Resíduo vegetal ,Floculação ,Ciências Exatas e da Terra - Abstract
This study aimed to evaluate the efficiency of aqueous extract of plant residue of chayote (Sechium edule SW.) As a natural coagulant in the treatment of textile effluents, using coagulation / flocculation technique. The effect of pH, FeCl3 dosage and dosage of the aqueous extract of the vegetable residue at chayote turbidity and chemical oxygen demand (COD) were investigate by testing jars by the standard test method. The optimization process of the treatment of textile effluent was conducted by response surface methodology (RSM) based on experimental design Box-Behnken, and the variables under study: FeCl3 dosage, dosage of plant residue extract chayote and pH, having as a percentage of the response to turbidity and COD. The characterization of the vegetable residue by chayote spectroscopy analysis by Fourier Transform Infrared (FTIR) spectra and 13C nuclear magnetic resonance solid (13C NMR / CPMAS) indicated that the residue showed absorption bands and typical signs of polysaccharides in case characteristic of anionic polyelectrolytes. As satisfying the conditions set by the experimental design were dosage FeCl3 = 47.40 mg L-1 dosage aqueous extract of plant residue chayote = 15.00 mg L-1 and pH = 6.14 obtaining removing percentage Turbidity and COD of 97.95% and 83.84% respectively. The results showed that the aqueous extract of chayote proved to be a natural coagulant potential, but this has greater efficiency when associated with a low dosage of FeCl3, with better performance as flocculation aid. Through this association was observe a 75% reduction of the FeCl3 dosage, indicating that the addition of the extract has improved the process efficiency by using a minimum dosage of FeCl3 O presente trabalho teve como objetivo avaliar a eficiência do extrato aquoso do resíduo vegetal do chuchu (Sechium edule SW.) como coagulante natural no tratamento de efluentes têxteis, empregando-se a técnica de coagulação/floculação. O efeito do pH, da dosagem de FeCl3 e da dosagem do extrato aquoso do resíduo vegetal do chuchu na remoção de turbidez e demanda química de oxigênio (DQO) foram investigados através de ensaios pelo método padrão de teste de jarros. O processo de otimização do tratamento do efluente têxtil foi realizado através da metodologia de superfície de resposta (RSM) baseada no planejamento experimental Box-Behnken, sendo as variáveis em estudo: dosagem de FeCl3, dosagem do extrato do resíduo vegetal do chuchu e pH, tendo como resposta a porcentagem de remoção de turbidez e DQO. A caracterização do resíduo vegetal do chuchu através de análises de Espectroscopia de Infravermelho por Transformada de Fourier (FTIR) e Ressonância Magnética Nuclear de 13C no estado sólido (RMN13C/CPMAS) indicaram que o resíduo apresentou bandas de absorção e sinais típicos de polissacarídeos, no caso característico de polieletrólitos aniônicos. As condições estabelecidas como ótimas através do planejamento experimental foram: dosagem de FeCl3 = 47,40 mg L-1, dosagem de extrato aquoso de resíduo vegetal do chuchu = 15,00 mg L-1 e pH = 6,14 obtendo porcentagem de remoção de turbidez e DQO de 97,95% e 83,84% respectivamente. Os resultados obtidos indicaram que o extrato aquoso do chuchu mostrou ser um potencial coagulante natural, porém esse possui maior eficiência quando associado a uma baixa dosagem de FeCl3, tendo melhor desempenho como auxiliar de floculação. Através dessa associação observou-se uma redução de 75% da dosagem de FeCl3, indicando que a adição do extrato melhorou a eficiência do processo utilizando uma dosagem mínima de FeCl3 xvii, 60 f.
- Published
- 2015
315. Fotodegradação artificial e solar de efluente têxtil : avaliação da atividade fotocatalítica dos catalisadores TiO2, ZnO e Nb2O5
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Souza, Renata Padilha de, Juliana Carla Garcia Moraes [Orientador] - UEM, Prof.ª Dr.ª Juliana Carla Garcia Moraes, Vitor de Cinque Almeida - UEM, Jesuí Vergilio Visentainer - UEM, Leda Maria Saragiotto Colpini - UFPR, and Giane Gonçalves Lenzi - UTFPR
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Efluente têxtil - Degradação artificial e solar ,Química analítica ,Química ,Fotodegradação ,Toxicidade ,Fotocatálise heterogênea ,Ciências Exatas e da Terra - Abstract
Environmental contamination has been pointed as one of the greatest problem of modern society, being the contamination of waters the biggest one. The textile industry is a major source of water pollution due to the generation of large volumes of wastewater. Textile effluents are highly colored and have high values of pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD) and other toxic chemicals to humans and the environment. In this work, heterogeneous photocatalysis was employed in the treatment of textile effluent from industrial laundry of jeans, in order to reduce their toxic organic load. The TiO2, TiO2 P25 (commercial), ZnO and Nb2O5 catalysts under artificial and solar irradiation were used. The parameters investigated under artificial irradiation, were: solution pH; catalyst concentration and the effect of mixed oxides (TiO2/Nb2O5 e ZnO/Nb2O5). From the optimal condition was performed the photodegradation under solar irradiation. The photocatalytic activity was evaluated by means of the kinetic efficiency (rate constant and half-life time), thermodynamic (decrease in absorbance: 228, 254, 284, 310, 350, 500 and 660 nm), reduction of COD, mineralization in terms of inorganic ions formation (NH4+, NO3-, NO2-, SO42- and Cl-) and toxicity reduction through bioassays with Artemia salina. The results indicated that kinetic and thermodynamic efficiency are affected by solution pH and catalyst concentration. It was found that the photocatalytic degradation of textile effluent at pH 3.0 and catalyst concentration of 0.250 g L-1 gave the best results, being found 95.91%; 87.35%; 86.95% and 59.18% of absorbance reduction at 660 nm (?max), after 300 min of artificial irradiation, for P25 TiO2, Nb2O5; TiO2 and ZnO, respectively. ZnO showed the lowest degradation rate, both under artificial light as in sunlight. The ZnO/Nb2O5 mixed significantly improved the photoactivity of ZnO, yielding approximately 27% of increase in the COD reduction. TiO2 and Nb2O5 were responsible for the reduction of approximately 70 and 66% of COD under artificial light and, 68 and 60% under sunlight, respectively. The photocatalytic activity was very close to TiO2 P25, confirmed by the efficiency in COD reduction, absorbance and inorganic ions formation, due to this, Nb2O5 becomes a promising alternative to replace the commercial TiO2 P25. The Artemia salina bioassays confirmed the efficacy of the treatment indicating that after the photodegradation there was a significant decrease of toxic compounds in wastewater, leading to a reduction in toxicity of 27.59% (in natura) to 77.52% and 131.95% in the presence of Nb2O5 under artificial and solar irradiation, respectively. The photocatalysis reduced the effluent toxicity up to 5 times, indicating that the intermediate and products formed showed no toxic A contaminação ambiental tem sido apontada como um dos maiores problemas da sociedade moderna, sendo a contaminação das águas o maior deles. A indústria têxtil constitui uma das maiores fontes de poluição aquática devido à geração de grandes volumes de efluentes. Os efluentes têxteis são altamente coloridos e possuem elevados valores de pH, demanda bioquímica de oxigênio (DBO), demanda química de oxigênio (DQO) e outros compostos químicos tóxicos ao homem e ao meio ambiente. Neste trabalho, a fotocatálise heterogênea foi empregada no tratamento do efluente têxtil, proveniente de lavanderia industrial de jeans, a fim de reduzir sua carga orgânica tóxica. Foram utilizados os catalisadores TiO2, TiO2 P25 (comercial), ZnO e Nb2O5, sob irradiação artificial e solar. Os parâmetros investigados, sob irradiação artificial, foram: pH da solução; concentração de catalisador e o efeito da mistura dos óxidos (TiO2/Nb2O5 e ZnO/Nb2O5). A partir da condição ótima realizou-se a fotodegradação sob irradiação solar. A atividade fotocatalítica foi avaliada por meio da eficiência cinética (constante de velocidade e tempo de meia vida), termodinâmica (redução de absorbância em: 228, 254, 284, 310, 350, 500 e 660 nm), redução de DQO, mineralização em termos de formação de íons inorgânicos (NH4+, NO3-, NO2-, SO42- e Cl-) e redução da toxicidade por meio de bioensaios com Artemia salina. Os resultados indicaram que a eficiência cinética e termodinâmica são afetados pelo pH da solução e pela concentração de catalisador. Verificou-se que a degradação fotocatalítica do efluente têxtil em pH 3,0 e concentração de catalisador 0,250 g L-1 obteve os melhores resultados, sendo encontrado 95,91%; 87,35%; 86,95% e 59,18% de redução de absorbância em 660 nm (?máx), após 300 min de irradiação artificial, para TiO2 P25, Nb2O5; TiO2 e ZnO, respectivamente. O ZnO apresentou a menor velocidade de degradação, tanto sob luz artificial quanto sob luz solar. A mistura ZnO/Nb2O5 melhorou significativamente a fotoatividade do ZnO, obtendo cerca de 27% de aumento na redução de DQO. TiO2 e Nb2O5 foram responsáveis pela redução de aproximadamente 70 e 66% de DQO sob luz artificial e 68 e 60% sob luz solar, respectivamente. A atividade fotocatalítica foi muito próxima à do TiO2 P25, fato confirmado pela eficiência na redução de DQO, absorbância e formação de íons inorgânicos, devido a isso, Nb2O5 torna-se uma alternativa promissora em substituição ao TiO2 P25 comercial. Os bioensaios com Artemia salina confirmaram a eficácia do tratamento, indicando que após a fotodegradação houve expressiva diminuição dos compostos tóxicos no efluente, levando a uma redução da toxicidade de 27,59% (in natura) para 77,52% e 131,95% na presença de Nb2O5 sob irradiação artificial e solar, respectivamente. A fotocatálise reduziu a toxicidade do efluente por até 5 vezes, indicando que os intermediários e produtos formados não apresentaram-se tóxicos vii, 113 f.
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- 2014
316. Chemical composition of grains from glyphosate-resistant soybean and its conventional parent under different edaphoclimatic conditions in Brazil
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Letícia Carlos Babujia, Adriana Pereira Silva, Polyana Batoqui França Biondo, Juliana Carla Garcia, José Marcos Gontijo Mandarino, and Jesui Vergilio Visentainer
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Glycine max ,transgenic soybean crop ,isoflavones ,fatty acids ,macro and micro minerals. ,Agriculture (General) ,S1-972 - Abstract
Glyphosate-tolerant (Roundup Ready®, RR) soybean is the most widely cultivated genetically modified crop in the world. The aim of this study was to evaluate, in a long-term field experiment, the chemical composition of grains in a pair of cultivars composed of the conventional parent (BRS 133) and the nearly isogenic transgenic (BRS 245RR) soybean. Plants were cropped under two different edaphoclimatic conditions in Brazil. The experiments began during the 2003/2004 growing season; samples were collected during the 2011/2012 harvest. Were quantified the contents of isoflavones (high performance liquid chromatography), fatty acids (gas chromatography), lipid and proteins (near infrared spectroscopy in the NIR - Near Infrared Reflectance) and minerals (atomic absorption flame spectrophotometry). All samples were analyzed in three replications. Major differences were observed between the two cultivation locations. In Ponta Grossa, which has lower temperatures and higher rainfall during the grain filling period, the contents of lipids and isoflavones were higher. In Londrina, which hassoil with higher fertility, the contents of minerals, proteins and carbohydrates in soybean grains were higher. Significant differences were observed between the cultivars. The conventional parent had higher protein contents and lower lipid contents. The transgenic soybean line had higher isoflavone contents.
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- 2015
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317. Efficiency and operating cost of electrocoagulation system applied to the treatment of dairy industry wastewater
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Henrique Cesar Lopes Geraldino, Julliana Izabelle Simionato, Thábata Karoliny Formicoli de Souza Freitas, Juliana Carla Garcia, Orlando de Carvalho Júnior, and Caryna Januario Correr
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conductivity ,COD ,electrolysis ,iron electrode ,oxidation. ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Science (General) ,Q1-390 - Abstract
The objective of this study was to apply the technique of electrocoagulation (EC) in the treatment of dairy industry wastewater, using a system of bench. It was used a source of 10 amps and an electrode of iron containing six plates of 14x6 cm. Were made variation of pH (4.5 to 6), intensity of electric current (1 to 2A) and time of electrolysis (30 to 60 min.). The efficiency of the treatment was confirmed by analysis of turbidity, color and COD. The reduction of turbidity was greater than 98%, reaching a record 99.98%. The largest reduction in color was 94.90% and 11 of the 27 tests the efficiency was greater than 90%. The greatest reduction of COD was 96.36%. The treatment proved to be more efficient at pH 4.5, time 60 min. and current 1.5A. The estimated cost of operation was US$ 1.04 m3 which demonstrates the viability of treatment of dairy industry wastewater.
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- 2015
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318. Application of chitin and chitosan extracted from silkworm chrysalides in the treatment of textile effluents contaminated with remazol dyes
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Julliana Isabelle Simionato, Lucas D. G. Villalobos, Milena Keller Bulla, Fabio Augusto Garcia Coró, and Juliana Carla Garcia
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chitin ,chitosan ,silkworm ,adsorption ,dyes ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Science (General) ,Q1-390 - Abstract
Chitin extracted from silkworm chrysalides was used to prepare chitosan applied in this investigation. Adsorption studies were carried out in column and in aqueous suspension with two dyes, blue remazol (RN) and black remazol 5 (RB). The study showed that adsorption is better in the chitosan-packed column than in the chitin-packed one. However, the comparison of the adsorption in column and in suspension revealed better results for the latter. The plotted Langmuir isotherm did not indicate significant difference in the theoretical capacity of saturation of the monolayer (Qo) for either dye. The application of the adsorption process to actual conditions was evaluated by adsorption assays of actual textile effluents. In acid pH, chitosan adsorbed the dyes responsible for the effluent coloration completely. This study showed that the use of chitosan obtained from silkworm chrysalides is a viable alternative for the immobilization of dyes in textile industry effluents.
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- 2014
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319. Pertussis in the central-west region of Brazil: one decade study
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Angelita Fernandes Druzian, Yvone Maia Brustoloni, Sandra Maria do Valle Leone Oliveira, Vanessa Terezinha Gubert de Matos, Adriana Carla Garcia Negri, Clarice Souza Pinto, Silvia Asato, Cirlene dos Santos Gonçalves Urias, and Anamaria Mello Miranda Paniago
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Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
In many parts of the world, numerous outbreaks of pertussis have been described despite high vaccination coverage. In this article we report the epidemiological characteristics of pertussis in Brazil using a Surveillance Worksheet. Secondary data of pertussis case investigations reported from January 1999 to December 2008 recorded in the Information System for Notifiable Diseases (SINAN) and the Central Laboratory for Public Health (LACEN-MS) were utilized. The total of 561 suspected cases were reported and 238 (42.4%) of these were confirmed, mainly in children under six months (61.8%) and with incomplete immunization (56.3%). Two outbreaks were detected. Mortality rate ranged from 2.56% to 11.11%. The occurrence of outbreaks and the poor performance of cultures for confirming diagnosis are problems which need to be addressed. High vaccination coverage is certainly a good strategy to reduce the number of cases and to reduce the impact of the disease in children younger than six months. Keywords: Whooping cough, Pertussis, Epidemiology, Bordetella pertussis, Outbreak investigation
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- 2014
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320. Textile-effluent treatment using Aloe vera mucilage as a natural coagulant prior to a photo-Fenton reaction.
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França Figueiredo, Franciele, Karoliny Formicoli de Souza Freitas, Thabata, Gonçalves Dias, Guilherme, Cesar Lopes Geraldino, Henrique, Paula Jambers Scandelai, Ana, Junkes Vilvert, Amanda, and Carla Garcia, Juliana
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ALOE vera , *COAGULANTS , *MUCILAGE , *ORGANIC compounds , *CHEMICAL oxygen demand - Abstract
[Display omitted] • Pre-treatment of the textile effluent was done with Aloe vera mucilage and FeCl 3. • Residual Fe3+ from the effluent was used for further photo-Fenton reactions. • The association of techniques proved to be an method efficient and viable. • Treated effluents showed no relevant toxicity at three trophic levels of organisms. In this study, the mucilage of Aloe vera was used as a new auxiliary coagulant in pre-treatment using a combined system based on the photo-Fenton (PF) process for the treatment of textile effluents. Coagulation–flocculation (CF) using a combination of coagulants showed better performance in the elimination of turbidity, chemical oxygen demand (COD), dissolved organic carbon (DOC), and natural organic matter (NOM) when compared with a single inorganic coagulant. In addition, the combination of coagulants allowed a 28% reduction in the concentration of the inorganic coagulant used. To remove the dissolved and recalcitrant matter after CF, the pretreated effluent was subjected to a PF process that is efficient in the degradation and mineralization of dissolved organic compounds; this resulted in the elimination of 82.48% of COD, 80.34% of DOC, and 79.65% of NOM, as well as the formation of inorganic ions. The toxicity of the samples was evaluated base on three organisms of different trophic levels: Lactuca sativa , Artemia salina, and Eisenia fetida. The results showed that the samples treated by CF or CF/PF were non-toxic to A. salina and E. fetida. However, in the L. sativa bioassay, the root-growth parameter revealed toxicity in the effluents before and after treatment, excluding the untreated effluents with doses of 100 and 200 mL L-1 and the effluent with a dose of 100 mL L-1 treated by the CF process. [ABSTRACT FROM AUTHOR]
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- 2022
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321. Development of tannin-based adsorbent applied to dye removal in aqueous systems
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Bonifácio, Evandro, Martins, Alessandro Francisco, Canesin, Edmilson Antonio, Santiago, Cosmo Damião, and Moraes, Juliana Carla Garcia
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Taninos ,Resíduos industriais ,Adsorção ,ENGENHARIAS::ENGENHARIA SANITARIA [CNPQ] ,Factory and trade waste ,Adsorption ,Tannins ,Engenharia/Tecnologia/Gestão - Abstract
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Este estudo apresenta um material adsorvente inovador, obtido a partir da diálise de uma solução aquosa de taninos condensados funcionalizados com grupos amino. Após diálise, o congelamento da solução dialisado leva à formação de um precipitado insolúvel em água (TND). O material dialisado foi caracterizado através de espectroscopia na região do infravermelho com transformada de Fourier (FT-IR), microscopia eletrônica de varredura (SEM), espectroscopia de fotoelétrons de raios-X (XPS) e medidas de potencial Zeta (PZ) obtendo valores de [zeta] positivos na faixa de pH 2,0 e 4,0, mantendo-se praticamente constantes ([zeta] = 5,0 mV). Porém, a partir de pH 4,0, os valores de [zeta] diminuem para valores negativos, alcançando -15,59 mV em pH 6,0, sugerindo a aplicabilidade na adsorção de corantes aniônicos e catiônicos . O adsorvente foi aplicado em estudos de adsorção para remoção dos corantes acid black 172 (AcB) e azul de metileno (AM). Estudos cinéticos e de equilíbrio foram realizados, onde o modelo cinético pseudo-primeira ordem apresentou melhor ajuste no processo de adsorção do AcB (R2 = 0,983), enquanto o modelo cinético pseudo-segunda ordem apresentou melhor ajuste para AM (R2 = 0,986). Para ambos os processos o modelo isotérmico que apresentou melhor ajuste foi o de Sips, em que, a quantidade máxima (qmax) removida dos corantes alcançou 99,5 mg g–1 para o AcB (R2 = 0,993) e 306,7 mg g–1 para o AM (R2 = 0,970). Avaliação termodinâmica revelou que o processo de adsorção é espontâneo, pois, apresentaram ΔG o negativos para AcB (–3,33 kJ mol–1) e para AM (–4,16 kJ mol–1). O processo de adsorção apresenta caráter físico e endotérmico. O TND apresentou potencial de regeneração, indicado por três ciclos de adsorção/dessorção. Após adsorção, espectros de XPS confirmaram à presença dos corantes na superfície do material adsorvente. O adsorvente à base de taninos apresenta eficiência para remover corantes de sistemas aquosos. This study presents an innovative adsorbent material, obtained from the dialysis of an aqueous solution of condensed tannins functionalized with amino groups. After dialysis, freezing the dialysate solution leads to the formation of a waterinsoluble precipitate (TND). The dialyzed material was characterized by spectroscopy in the infrared region with Fourier transform (FT-IR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Zeta potential measurements (PZ) obtaining values positive in the pH 2.0 and 4.0 range, remaining practically constant ([zeta] = 5.0 mV). However, from pH 4.0, the values of [zeta] decrease to negative values, reaching -15,59 mV at pH 6.0, suggesting the applicability in the adsorption of anionic and cationic dyes. The adsorbent was applied in adsorption studies to remove the dyes acid black 172 (AcB) and methylene blue (AM). Kinetic and equilibrium studies were performed, where the pseudo-first order kinetic model showed better fit in the adsorption process of the AcB (R2 = 0.983), while the pseudo-second order kinetic model showed better fit for AM (R2 = 0.986). For both processes, the isothermal model that showed the best fit was the Sips model, in which the maximum amount (qmax) removed from the dyes reached 99.5 mg g–1 for AcB (R2 = 0.993) and 306.7 mg g–1 for the AM (R2 = 0.970). Thermodynamic evaluation revealed that the adsorption process is spontaneous, since they presented negative ΔGo for AcB (–3.33 kJ mol–1) and for AM (–4.16 kJ mol–1), the adsorption process has a physical character and endothermic. TND showed regeneration potential, indicated by three cycles of adsorption/desorption. After adsorption, XPS spectra confirmed the presence of dyes on the surface of the adsorbent material. The tannin-based adsorbent is efficient for removing dyes from aqueous systems.
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- 2020
322. Synthesis and characterization of polyurethane/silica extracted from rice husk composites for effluent treatment
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Hugo Vinicius Souza Costa, Gizilene Maria de Carvalho ., Maria Josefa Santos Yabe, and Juliana Carla Garcia Moraes
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A remoção ou recuperação de óleo de ambientes aquáticos através do uso de sorventes é o método mais utilizado devido às altas taxas de remoção, baixo custo, recuperação do óleo e reutilização do sorvente. A utilização de compósitos poliméricos para a produção de sorventes necessita de conhecimento dos processos cinéticos de sorção e da relação entre a estrutura do material sintetizado e os mecanismos de sorção. Este estudo propõe a síntese de um compósito de poliuretano e sílica extraída da casca de arroz como uma alternativa para o destino de um resíduo agroindustrial e de questões ambientais em diferentes frentes. Para a síntese dos compósitos, sílica foi extraída da casca de arroz, sofrendo um processo de redução de tamanho de partículas. O tamanho das partículas foi reduzido em aproximadamente 120% com secagem por liofilização (90 nm aproximadamente). A sílica foi modificada quimicamente e foi utilizada como reforço na síntese de espumas de poliuretano. Foi avaliada a influência da quantidade e do tipo de sílica utilizada na morfologia e na capacidade de sorção de óleo e de solventes orgânicos com diferentes polaridades dos compósitos produzidos. Segundo as análises de MEV, BJH e DH, a morfologia das espumas, bem como sua quantidade e tamanho dos poros não variou de forma significativa de acordo com a sílica utilizada na síntese. Apenas a espuma PU-0,1SLM apresentou a degradação térmica mais acentuada que as outras espumas após T90, bem como um aumento repentino na degradação em 566°C. A cinética de sorção de óleo pelas espumas se mostrou melhor descrita pelo modelo de pseudo-segunda ordem, indicando que a adsorção acontece em dois tipos de sítios de sorção, e os parâmetros de sorção aumentam consideravelmente quando em meio úmido quando comparados aos de meio seco. A capacidade de sorção de outros solventes orgânicos pela espuma foi testada, e foi concluído que a espuma apresenta parâmetros de sorção maiores conforme o aumento da polaridade do solvente, sendo um potencial agente no controle de efluentes industriais polares. The removal or recovery of oil from aquatic environments using sorbents is the most used method due to the high rates of removal, low cost, oil recovery and sorbent reuse. The use of polymeric composites to produce sorbents requires knowledge of the sorption kinetic processes and the relationship between the structure of the synthesized material and the sorption mechanisms. Thus, this work proposes the synthesis of a composite made from polyurethane and silica extracted from rice husk as an alternative for the disposal of agro-industrial residues, with the objective of addressing environmental issues on different fronts. Silica particles from rice husk were decreased by approximately 120% up to 90 nm by freeze-drying, to synthesize the composites. The silica was chemically modified to give better properties to the material and was used as reinforcement to polyurethane foams in the composite. The influence of the amount and type of silica used in the morphology and in the sorption capacity of oil and organic solvents with different polarities of the produced composites was evaluated. According to the SEM, BJH and DH results, the foam morphology, as well as its quantity and pore size did not vary significantly depending on the silica used in the synthesis. Only the PU-0.1SLM foam showed relevant differences in the thermogravimetric analysis curve, with more pronounced thermal degradation than the other foams after T90, as well as a sudden increase in degradation at 566°C. The kinetics of oil sorption by foams proved to be better described by the pseudo-second order model, indicating that the adsorption occurs by two types of sorption sites, and the sorption parameters increase considerably when in humid environments compared with dry environments. In addition, the sorption capacity of other organic solvents by the foam increases with the solvent polarity, demonstrating greater effectiveness for organic solvent sorption than for oil removal. Therefore, the produced composite is a potential agent to control polar industrial effluents.
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- 2020
323. Reply to Maadan et al.
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Downey, Rachel, McElvain, Dawn, Murphey, Donald K., Bailey, Ann, Patel, Bhairav, Fernandez, Marisol, Loftis, Laura, Carreno, Carla Garcia, Eger, Lynne, Aguilera, Elizabeth, Wootton, Susan, Castignini, Luis, and Hauger, Sarmistha B.
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MYCOPLASMA pneumoniae infections , *RANGE of motion of joints , *HOSPITAL care of children , *NEUROMUSCULAR diseases , *MYELITIS , *CENTRAL nervous system viral diseases - Published
- 2020
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324. Fotocatálise heterogênea aplicada à remoção de sulfametoxazol e N4-acetilsulfametoxazol
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Melo, Joelma Ribeiro de, Gimenes, Marcelino Luiz, Fernandes-Machado, Nádia Regina Camargo, Marques, Rubiane Ganascim, Lima, Ana Maria Ferrari, Moraes, Juliana Carla Garcia, and Souza, Marcos de
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Imobilização ,660.2995 ,Engenharias ,Engenharia Química ,Fotocatálise heterogênea ,Sulfametoxazol - Abstract
Orientador: Prof. Dr. Marcelino Luiz Gimenes Coorientadora: Prof.ª Dr.ª Nádia Regina Camargo Fernandes Machado Tese (doutorado em Engenharia Química) - Universidade Estadual de Maringá, 2018 RESUMO: A contaminação de ambientes aquáticos por poluentes de qualquer natureza desperta atenção devido à extrema importância da água. Os antibióticos têm recebido atenção especial devido à capacidade de desenvolvimento de genes de resistência em bactérias patogênicas no meio ambiente e ao caráter de persistência e bioacumulação. Este trabalho teve como objetivo aplicar a fotocatálise heterogênea no tratamento de efluente sintético contendo o antibiótico sulfametoxazol (SMX) e o metabólito n4-acetisulfametoxazol (AcSMX) na presença do catalisador formado por dois óxidos multifuncionais: o óxido de zinco e o dióxido de titânio. ZnO foi sintetizado a partir de dois precursores diferentes, o nitrato (ZnO-A) ou acetato de zinco (ZnO-B) e, o butóxido de titânio para a obtenção do TiO2. O catalisador foi obtido a partir da síntese do ZnO particulado seguido da mistura à solução do precursor de TiO2. A imobilização via dip-coating foi realizada em lâminas de vidro previamente tratadas por lixamento. Os catalisadores foram primeiramente caracterizados para identificar as propriedades estruturais por difração de raios X (DRX) e espectroscopia Raman. Análise química por espectroscopia no infravermelho (FTIR), microscopia eletrônica de varredura (MEV) e transmissão (MET) para análise morfológica. A composição química foi avaliada por espectroscopia de energia dispersiva (EDS) e fotoeletrônica por raios X (XPS). Análise óptica por espectroscopia fotoacústica (PAS) para determinação da energia de band gap. A determinação das propriedades semicondutoras e eletrônicas foi pela caraterização fotoeletroquímica em potencial a circuito aberto (PCA), voltametria (linear e ciclíca) e cronoamperometria. A atividade fotocatalítica foi avaliada em relação à remoção do SMX e AcSMX em água, na concentração de 6,00 mg.L-1, utilizando radiação artificial UV-Vis (15 W), durante 4 h e como catalisadores: TiO2, TiO2/ZnO-A e TiO2/ZnO-B; imobilizados em lâminas de vidro. O efeito do pH (4,0, 7,0 e 9,0) na remoção dos contaminantes e na estabilidade química do ZnO também foi avaliado. O catalisador com melhor desempenho foi utilizado em reações de 4 h e 12 h, avaliando a ecotoxicidade do efluente final com sementes de alface (Lactuca sativa) e microcrustáceo (Artemia salina). A presença de ZnO na fase wurtzita e o TiO2 na fase anatase foram identificadas na heteroestrutura formada, sendo observada em todas a caraterizações realizadas, indicando a interação entre os óxidos formados. O tipo do ZnO adicionado ao TiO2, afetou as propriedades eletrônicas do material heteroestruturado TiO2/ZnO, apesar de ter sido adicionada a mesma quantidade de ZnO (mesma proporção). Em pH 4,0, a remoção do SMX foi mais efetiva, alcançando valores de 59,04% (TiO2), 61,04% (TiO2/ZnO-A) e 40,24% (TiO2/ZnO-B), mas ZnO não foi estável químicamente, apresentando indícios de lixiviação em solução ao final da reação (4 h) para os catalisadores TiO2/ZnO. Entre os óxidos estudados na degradação dos compostos, em pH 7,00, TiO2/ZnO-A foi o catalisador mais eficiente, alcançando 56,17% (SMX) e 31,36% (AcSMX) em 4 h de reação e 88,76% (SMX) e 51,66% (AcSMX) em 12 h de reação. Este resultado foi atribuído ao sinergismo da heterojunção dos óxidos sobre as propriedades eletrônicas do material, pois apresentou o maior tempo de vida e a menor taxa recombinação do par fotogerado. AcSMX mostrou ser resistente à remoção, gerando subprodutos com potencial tóxico, como o SMX, identificado em análise cromatográfica, sendo necessário um tempo muito elevado para que fosse possível sua completa eliminação, indicando a inviabilidade do processo fotocatalítico nas condições avaliadas ABSTRACT: Contamination of aquatic environments by pollutants of any kind arouses attention due to the extreme importance of water. Antibiotics have received special attention because of the ability to develop resistance genes in pathogenic bacteria in the environment and to the character of persistence and bioaccumulation. This work aimed to apply heterogeneous photocatalysis in the treatment of synthetic effluent containing the antibiotic sulfamethoxazole and the metabolite n4-acetylsulfametoxazole in the presence of the catalyst formed by two multifunctional oxides: zinc oxide and titanium dioxide. ZnO was synthesized from two different precursors, the zinc nitrate (ZnO-A) or zinc acetate (ZnOB) and the titanium butoxide to obtain the TiO2. The catalyst was obtained from the isolated ZnO powder synthesis followed by adding to the solution of the TiO2 precursor. The immobilization by dip-coating was performed on glass slides previously treated by sanding. The catalysts were first characterized to identify structural by X-ray diffraction (XRD) and Raman spectroscopy. The chemical analysis was done by infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) and microscopy electron transmission (MET) for morphological analysis. The chemical composition was evaluated by dispersive energy (EDS) and X-ray photoelectron spectroscopy (XPS), for superficial chemical composition. Optical analysis by photoacoustic spectroscopy (PAS) was done to determine band gap energy. The determination of the semiconductor and electronic properties was by photoelectrochemical characterization in open circuit potential (OCP), voltammetry (linear and cyclic) and chronoamperometry. The photocatalytic activity was evaluated by the removal of SMX and AcSMX in water, at a concentration of 6.00 mg.L-1, using UV artificial radiation (15 W) for 4 h and as catalysts: TiO2, TiO2/ZnO-A e TiO2/ZnO-B immobilized on glass slides. The effect of pH (4.0, 7.0 and 9.0) on removal of contaminants and chemical stability of ZnO was evaluated too. The best performance catalyst was used in 4 h and 12 h reactions, evaluating the ecotoxicity of the final efluente with lettuce seeds (Lactuca sativa) and microcrustacean (Artemia salina). The presence of ZnO in the wurtzite phase and the TiO2 in the anatase phase were identified in the formed heterostructure, being observed in all characterizations performed, indicating the interaction between the oxides formed. The type of ZnO added to TiO2 affected the electronic properties of the TiO2/ZnO heterostructured material, although the same amount of ZnO (same ratio) was added. At pH 4.0, the SMX removal was more effective, reaching values of 59.04% (TiO2), 61.04% (TiO2/ZnO-A) and 40.24% (TiO2/ZnO-B), but ZnO was not chemically stable, showing signs of leaching at the end of the reaction (4 h) for TiO2/ZnO catalysts. Among the studied oxides, at pH 7.0, TiO2/ZnO-A was the most efficient catalyst, reaching 56.17% (SMX) and 31.36% (AcSMX) in 4 h of reaction and 88.76% (SMX) and 51.66% (AcSMX) in 12 h of reaction. This result was attributed to the synergism of the heterojunction of the oxides on the electronic properties of the material, since it presented the longest life time and the lowest recombination rate of the photogenerated pair. The AcSMX showed to be resistant to photocatalytic removal, generating degradation products with toxic potential, such as SMX, identified in chromatographic analysis, requiring a very high time for its complete elimination under the conditions evaluated, indicating the inviability of the photocatalytic process under the conditions evaluated xvi, 163 f. : il. (algumas color.).
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- 2018
325. Wastewater treatment using Mg-doped ZnO nano-semiconductors: A study of their potential use in environmental remediation.
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Oliveira, Angélica Gonçalves, Andrade, Jéssica de Lara, Montanha, Maiara Camotti, Ogawa, Camilla Yara Langer, de Souza Freitas, Thábata Karoliny Formicoli, Moraes, Juliana Carla Garcia, Sato, Francielle, Lima, Sandro Marcio, da Cunha Andrade, Luis Humberto, Hechenleitner, Ana Adelina Winkler, Pineda, Edgardo Alfonso Gómez, and de Oliveira, Daniela Martins Fernandes
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WASTEWATER treatment , *ENVIRONMENTAL remediation , *ELECTRON-hole recombination , *BAND gaps , *LAUNDRY equipment , *WATER reuse , *DISINFECTION & disinfectants - Abstract
• Photocatalytic activity of Mg-doped ZnO was enhanced upon increased Mg2+ content. • Photodegradative process disinfected and improved the BOD 5 /COD ratio of wastewater. • Phytotoxicity tests showed that treated wastewater can be used in agriculture. • Mg-doped ZnO did not inhibit the proliferation of fibroblast cells. Structural, morphological, optical, and photocatalytic properties of Mg-doped ZnO nano-semiconductors were investigated. All nanostructures exhibited spherical morphology with average crystallite diameters and band gap energy values between 47–54 nm and 3.00–3.05 eV, respectively. The increase in Mg ion contents (0.1–1.0 mol%) enhanced the photocatalytic activity of the nano-semiconductors for decontamination of non-treated laundry wastewater, degrading approximately 53% of pollutants (with absorption at λ = 290 nm) after 240 min of UV–vis irradiation. The best photocatalytic efficiency exhibited by ZnO-Mg 1.0% is probably associated to an increase in the amount of oxygen vacancies (V O) and consequent reduction in the recombination rate of electron-hole (e–h) pairs. The treatment of laundry wastewater also demonstrated reduction of 31% in total organic carbon (TOC), improvement in the biodegradability of the contaminants, and a high efficacy in wastewater disinfection. In addition, the treated laundry wastewater promoted a germination rate of cucumber seeds equivalent to the observed rate for the control. Phytotoxicity of treated wastewater on tomato roots reduced about 73%, indicating that the treated laundry wastewater does not essentially need to be disposed into water bodies. Instead, it may be reused as irrigation water. Interestingly, Mg-doped ZnO nano-semiconductors did not cause damage to normal and healthy fibroblast cells, demonstrating their potential to be used in environmental remediation, considering the low-cost, non-toxicity, and high efficiency of these nanomaterials. [ABSTRACT FROM AUTHOR]
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- 2021
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326. Análise direta de amostras de vinho por F AAS para a determinação de Fe e relação de sua concentração com o teor de polifenóis totais
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Sobieski Neto, Eduardo, Garcia, Edivaldo Egea, Moraes, Juliana Carla Garcia, Montanher, Paula Fernandes, Universidade Estadual de Maringá, Centro de Ciências Exatas, Departamento de Química, and Programa de Pós-Graduação em Química
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Vinho - Polifenóis ,Vinho - Espectrometria de absorção atômica em chama (F AAS) ,Vinho - Ferro (Fe) ,Vinho - Potencial hidrogeniônico (pH) - Abstract
Orientador: Prof. Dr. Edivaldo Egea Garcia Dissertação (mestrado em Química) - Universidade Estadual de Maringá, 2016 Estudos desenvolvidos no mundo inteiro comprovam que o vinho tomado em quantidade moderada, contribui para a saúde do organismo humano, aumentando a qualidade e o tempo de vida. Como a presença de Fe, compostos fenólicos, pH e teor alcoólico afetam propriedades que estão relacionadas com as características organolépticas e à segurança com que o produto é consumido, o objetivo deste trabalho é realizar análise direta de amostras de vinho por F AAS para a determinação de Fe e fazer a avaliação da relação de sua concentração com o teor de polifenóis, pH e teor alcoólico. Foram analisadas 45 amostras de vinho, quanto ao tipo (mesa e fino), quanto a cor (branco e tinto) e quanto a variedade da uva (Sauvignon Blanc, Cabernet Sauvignon e Merlot). Os resultados para as determinações de Fe variaram na faixa de 0,19 ± 0,01 a 4,75 ± 0,04, e os limites de detecção e quantificação (LOD e LOQ) determinados foram de 0,037 e 0,123 mg L-1, respectivamente. As recuperações obtidas pelos testes de adição recuperação variaram de 99 a 106%, indicando exatidão para os resultados obtidos para as determinações de Fe nesse tipo de amostra. Os teores de Polifenóis Totais foi determinado pelo método espectrofotométrio de Folin-Ciocalteu e os seus valores variaram de 49,27 ± 1,2 a 3724 ± 161 mg AG L-1. Os valores de pH determinados para as amostras de vinho neste trabalho variaram de 3,03 a 3,88 enquanto que os teores alcoólicos variaram de 9,5 a 13,5% (v v-1). A partir de analises estatísticas de conglomerados e análise de componentes principais (ACP), observou-se uma relação direta entre os teores de Fe e de Polifenóis Totais para as determinações realizadas nas amostras de vinho branco e vinhos tintos finos suave e meio seco. A relação inversa foi observada para os vinhos de mesa e os vinhos tintos seco. As variáveis pH e teor alcóolico foram as responsáveis na separação dos vinhos de mesa e finos. Em relação ao tipo das uvas apenas a Sauvignon Blanc distinguiu-se das demais, enquanto que para as variedades Cabernet Sauvignon e Merlot não foi possível observar um padrão avaliando-se os parâmetros estudados Studies conducted worldwide, prove that wine taken in moderate amounts, contributes to the health of the human organism, increasing the quality and length of life. Like the presence of Fe, phenolic compounds, pH, and alcohol affect properties that are related to the organoleptic characteristics and safety to which the product must be consumed, and this work aims is to perform direct analysis of wine samples by F AAS for the determination of Fe and make the assessment of its concentration with the polyphenol and alcohol contents, and pH. A total of 45 wine samples of different types (table and fine), colors (white and red), and grape varieties (Sauvignon Blanc, Cabernet Sauvignon and Merlot) were analysed. The results for the Fe determinations ranged from 0.19 ± 0.01 to 4.75 ± 0.04, and the limits of detection and quantification (LOD and LOQ) obtained were 0.037 e 0.123 mg L-1, respectively. The obtained recoveries by employing addition recovery tests ranged from 99 to 106% and indicated accuracy for determination of Fe in wine samples. Total Polyphenols content was determined by the spectrophotometric method of Folin-Ciocalteu and results obtained ranged from 49.27 ± 1.2 to 3724 ± 161 mg GA L-1. The results obtained for the pH values in the wine samples analysed ranged from 3.03 to 3.88, while the alcoholic content for the same samples ranged from 9,5 to 13,5% (v v-1). From results obtained by employing the both principal componente analysis (PCA) and statistical cluster analysis could be observed a direct relationship between Fe and Total Polyphenols contents for the white and sweet red wine samples. The inverse relationship was observed for table wines and dry red wines. The pH and alcohol content were responsible for the separation of table and fine wines. Regarding the grape variety, the Sauvignon Blanc grapes distinguished from the others, while for the varieties Cabernet Sauvignon and Merlot it was not possible to observe a pattern of classification by evaluating the parameters studied
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- 2016
327. Síntese, caracterização e atividade de fotocatalisadores suportados de óxido de zinco em zeólitas
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Batistela, Vagner Roberto, Hioka, Noboru, Fernandes-Machado, Nádia Regina Camargo, Moraes, Juliana Carla Garcia, Moisés, Murilo Pereira, Lima, Ana Maria Ferrari, Universidade Estadual de Maringá, Centro de Ciências Exatas, Departamento de Química, and Programa de Pós-Graduação em Química
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Catalisadores ,Zeólitas ,541.395 ,Fotocatálise - Abstract
Orientador: Prof. Dr. Noboru Hioka Coorientadora: Prof.ª Dr.ª Nádia Regina Camargo Fernandes-Machado Tese (doutorado em Química) - Universidade Estadual de Maringá, 2016 Diversas abordagens têm sido propostas para facilitar o maior uso da fotocatálise para o tratamento de poluentes recalcitrantes. Uma delas, consiste em buscar fotocatalisadores com propriedades semelhantes ao do mais estudado (TiO2) e uma outra, de que a fase foto-ativa possa ser economizada, e se possível, reutilizada. Nesse sentido, essas duas abordagens são envolvidas no presente estudo: catalisadores de ZnO suportados em zeólitas. Sintetizou-se catalisadores de ZnO impregnados em três zeólitas de uso comercial NaA, NaY e USY por métodos de impregnação úmida e deposição. Os catalisadores foram caracterizados por espectroscopia de absorção atômica, difratometria de raios-X, espectroscopia no infravermelho, espectroscopia Raman, microscopia eletrônica de transmissão, análise textural mediante fissiossorção de N2 e CO2 e ponto de carga zero. A atividade fotocatalítica foi investigada usando o ácido salicílico (1,00x10-4 mol/L) como substrato modelo para a reação de fotodegradação em dois sistemas foto-reatores diferentes: o primeiro, consistindo de um foto-reator convencional com lâmpada de mercúrio de alta pressão de 250 W sem o bulbo e o segundo, um mini-reator consistindo de um dispositivo LED-UV de 5W com monitoramento contínuo e simultâneo da fotorreação no interior de cubetas de quartzo via espectrofotometria UV-Vis. Os catalisadores sintetizados por impregnação úmida tiveram a cristalização do ZnO regulada pelo tamanho dos microporos. No catalisador 10NaA, o ZnO cristalizou na parte externa em cristalitos pequenos e no 10NaY e 10USY no interior dos microporos. Como consequência, a atividade desses três catalisadores foi baixa. Os catalisadores obtidos por deposição apresentaram cristalitos de ZnO maiores e com maior porcentagem de cristalinidade o que contribuiu para maior atividade destes do que aqueles preparados por impregnação úmida. Dos três catalisadores obtidos por deposição, o mais ativo para a degradação do ácido salicílico foi o 10USY, provavelmente por ser o que apresenta a maior área externa (83,5 m2/g) o que favorece o ataque das espécies oxidativas ao substrato. Estudos de pH foram realizados indicando que este parâmetro exerce influência significativa na fotodegradação do AS com ZnO puro mas pouco afeta na ação dos catalisadores suportados. Dessa forma, em pH 8,0, a dosagem ótima do catalisador foi de 3,00 g/L. Comparativamente os estudos entre os foto-reatores convencional e com dispositivo LED-UV, as constantes de velocidade para a degradação do ácido salicílico foram menores nas condições ótimas com o sistema LED-UV ([ZnO] = 0,20 g/L; k = 5,72 x10-3 min-1) em relação ao foto-reator convencional ([ZnO] = 3,00 g/L; k = 18,21 x10-3 min-1), em pH 8,0. Mesmo assim, o sistema LED-UV com monitoramento contínuo foi considerado um sistema satisfatório e muito interessante para o estudo de reações fotocatalíticas Several approaches have been proposed to facilitate greater use of photocatalysis to treat recalcitrant pollutants. One of them consists in seeking photocatalysts with similar properties to the most studied (TiO2) and another of the photo-active phase can be saved and reused if possible. In this sense, these two approaches are involved in this study: ZnO catalysts supported on zeolites. It was synthesized ZnO catalysts impregnated in three industrial use zeolites NaA, NaY and USY by wet impregnation and deposition methods. The catalysts were characterized by atomic absorption spectroscopy, X-ray diffraction, infrared spectroscopy, Raman spectroscopy, transmission electron microscopy, textural analysis by physisorption N2 and CO2 and zero point charge. The photocatalytic activity was investigated using the salicylic acid (1,00x10-4 mol/L) as a model substrate for the photodegradation reaction in two two different systems: the first consisting of a conventional photo-reactor with high-pressure mercury lamp 250 W without bulb and the second, a mini-reactor consisting of an LED-UV device 5W with continuous and simultaneous monitoring of the photoreaction within quartz cuvettes via UV-Vis spectrophotometry. The catalysts synthesized by the wet impregnation ZnO crystallization were governed by the size of the micropores. In the catalyst 10NaA, ZnO crystallized in the outer into small crystallites and 10NaY and 10USY within the micropores. As a result, the activity of these three catalysts was low. The catalysts obtained by deposition showed crystallites larger of ZnO and with a higher percentage of crystallinity which contributed to increased activity of these than those prepared by wet impregnation. Of the three catalysts obtained by deposition, the most active for the degradation of salicylic acid was the 10USY likely to be the one with the largest outdoor area (83.5 m2 / g) which favors the attack of oxidative species to the substrate. pH studies performed indicated that this parameter has a significant influence on AS photodegradation with pure ZnO but little effect on the action of the supported catalysts. Thus, at pH 8.0, the optimal dosage of the catalyst was 3.00 g/L. Comparatively studies between conventional photo-reactors and LED -UV device , the rate constants for degradation of salicylic acid were lower in optimal conditions with the LED -UV system ([ZnO] = 0.20 g/L; k = 5,72 x10-3 min- 1) compared to conventional photo-reactor ([ZnO] = 3.00 g/L; k = 18,21 x10-3 min-1 ) at pH 8.0. Still, the LED-UV system with continuous monitoring was considered a satisfactory system and very interesting for the study of photocatalytic reactions
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- 2016
328. Síntese, caracterização e atividade fotocatalítica de óxidos nanoestruturados puros e dopados de zinco e alumínio
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Andrade, Jéssica de Lara, Oliveira, Daniela Martins Fernandes de, Moraes, Juliana Carla Garcia, Matos, Roberto de, Universidade Estadual de Maringá, Centro de Ciências Exatas, Departamento de Química, and Programa de Pós-Graduação em Química
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Nanotecnologia ,Semicondutores ,Óxido de alumínio ,Físico-química ,Fotocatálise - Aplicaçöes ,Óxidos dopados nanoestruturados - Síntese - Caracterização ,Óxido de Zinco ,Química ,620.5 ,Ciências Exatas e da Terra - Abstract
Orientador: Profª. Drª. Daniela Martins Fernandes de Oliveira Dissertação (mestrado em Química)--Universidade Estadual de Maringá, 2016 Resumo: No presente trabalho foram sintetizados semicondutores nanoestruturados à base de óxidos de zinco e alumínio puros (ZnO e Al2O3), e dopados (ZnO-Al x e Al2O3-Zn x, com x igual a 1, 3, 5 e 10% em mol do respectivo íon dopante), através de um método sol-gel modificado. As propriedades estruturais, ópticas e também a morfologia destes óxidos foram investigadas por FTIR, DRX, Raman, PAS, PL, MET e MEV. Bandas de absorção características de vibrações Zn-O e Al-O foram detectadas nos espectros de FTIR dos respectivos óxidos puros e dopados. Os óxidos de zinco dopados com Al3+ calcinados a 500ºC apresentaram picos cristalográficos característicos do ZnO, e a incorporação do íon dopante causou uma significativa diminuição no tamanho médio de cristalito de 25 para 7 nm. Os óxidos de alumínio dopados com Zn2+ calcinados a 1100ºC exibiram picos característicos das fases cristalinas e -Al2O3, e o tamanho médio de cristalito também diminuiu com a dopagem, de 41 para 34 nm. A energia de banda gap (Eg) do ZnO diminuiu de 3,12 para 2,95 eV com a inserção de 3% em mol de Al3+, enquanto que a Eg do Al2O3 diminuiu de 4,01 para 3,88 eV, quando 10% em mol de íons Zn2+ foram incorporados. A ampla fotoluminescência do ZnO centrada ao redor de 550 nm teve sua intensidade aumentada com a incorporação de íons Al3+. No entanto, a intensa emissão do Al2O3 diminuiu consideravelmente com a inserção de íons Zn2+. Tais mudanças nas propriedades ópticas de ambos os óxidos com a dopagem podem estar relacionadas com o aumento de defeitos estruturais, como vacâncias de oxigênio, como sugerido também a partir dos resultados de Raman. As nanopartículas de Al2O3 puro e dopado com íons Zn2+ apresentam morfologia alongada semelhante à nanoneedles, enquanto que os óxidos dopados ZnO-Al x, exibem morfologia lamelar, diferente do ZnO puro que exibe um aspecto mais poroso. A atividade fotocatalítica dos óxidos sintetizados foi avaliada frente à degradação do corante Vermelho Congo, sob luz visível, em pH 12,0 e concentração de óxido igual a 1,000 g L-1. Estes estudos demonstraram que a eficiência fotocatalítica dos óxidos puros diminui com a dopagem e também, que os óxidos ZnO-Al x exibem atividade fotocatalítica superior aos óxidos Al2O3-Zn x. Após 300 minutos de irradiação sob luz visível, o ZnO degradou aproximadamente 96% do corante VC, seguido do ZnO-Al 1% que degradou cerca de 80% deste corante. Por sua vez, o Al2O3, apresentou uma taxa de degradação de 43% para o VC nas mesmas condições mencionadas anteriormente, seguido do Al2O3-Zn 10%, o qual degradou apenas 28% do corante Abstract: In the present work nanostructured semiconductors based on zinc and aluminium oxides (ZnO e Al2O3), and doped (ZnO-Al x and Al2O3-Zn x, with x equal to 1, 3, 5 e 10 in mol% of respective dopant ion) were synthesized by means of modified sol-gel method. Structural, optical and morphological properties of these oxides were investigated by means of FTIR, XRD, Raman, PAS, PL, TEM and SEM. Characteristic absorption bands of vibrations Zn-O and Al-O were detected in the FTIR spectra of the respective pure (undoped) and doped oxides. Al3+ doped zinc oxides were calcined at 500 °C and showed crystallographic peaks characteristic of ZnO, and the incorporation of Al3+ dopant caused a significant decrease in the average crystallite size from 25 to 7 nm. Zn2+ doped aluminum oxides calcined at 1100ºC exhibited peaks characteristic of and -Al2O3 crystalline phases, and the average crystallite size also decreased with the doping, from 41 to 34 nm. The band gap energy (Eg) of the ZnO decreased from 3.12 to 2.95 eV with the insertion of 3 mol% of Al3+, while for Al2O3 the Eg decreased from 4.01 to 3.88 eV, when 10 mol% of Zn2+ ions were incorporated. The intensity of the large photoluminescence of ZnO centered at approximately 550 nm increased with the addition of Al3+. However, the intense emission of Al2O3 was significantly reduced with insertion of Zn2+. These changes on optical properties of both oxides with the doping can be associated with increases of structural defects, such as oxygen vacancies, as suggested also by Raman results. Undoped and Zn-doped Al2O3 nanoparticles showed elongated morphology similar to nanoneedles, whereas the ZnO-Al x oxides exhibited lamellar morphology, different from the morphology exhibited by undoped ZnO, which shows a porous aspect. The photocatalytic activity of the synthesized oxides was evaluated for Congo Red (CR) photodegradation, under visible light, at pH 12.0 and oxide concentration of 1.000 g L-1. These studies demonstrated that the photocatalytic efficiency of undoped oxides decreases with the insertion of dopants and, the ZnO-Al x oxides exhibit higher photocatalytic activity than Al2O3-Zn x oxides. After a 300-min irradiation with visible light, ZnO degraded approximately 96% of CR dye, followed by ZnO-Al 1% which degraded around 80% of this dye. Al2O3 showed a degradation rate of 43% for the CR dye, followed by Al2O3-Zn 10%, which degraded only 28% of this dye
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- 2016
329. Síntese de biocompósitos a base de poliuretano e aplicação como adsorvente para o corante têxtil amarelo procion HE 4R e biodiesel
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Bulla, Milena Keller, Moraes, Juliana Carla Garcia, Visentainer, Jesuí Vergílio, 1959, Souza, Nilson Evelázio de, Montanher, Paula Fernandes, Palácio, Soraya Moreno, Universidade Estadual de Maringá, Centro de Ciências Exatas, Departamento de Química, and Programa de Pós-Graduação em Química
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Resíduos industriais - Poliuretano ,Poliuretanos ,Celulose - Madeira macerada ,543.0892 - Abstract
Orientadora: Prof.ª Dr.ª Juliana Carla Garcia Moraes Tese (doutorado em Química) - Universidade Estadual de Maringá, 2016 O presente trabalho teve o objetivo de desenvolver compósitos na forma de espumas à base de poliuretano, com a finalidade de substituir o polímero sintético utilizado na produção das espumas e verificar a adsorção frente à potenciais contaminantes. O polímero foi substituído por amido de mandioca e por resíduos industriais: resíduo de madeira e resíduo de mandioca. A adsorção foi realizada com o corante têxtil Amarelo Procion HE 4R (AP) e com biodiesel. O resíduo de madeira foi tratado por maceração, obteve-se a celulose, a qual foi modificada e utilizada na síntese dos compósitos, assim como o resíduo tratado. A celulose, a celulose modificada, o amido de mandioca e resíduo de mandioca foram caracterizados por FTIR, TGA e RMN 13C. Os compósitos foram submetidos aos testes de adsorção com variação de pH, tempo de adsorção e concentração inicial de solução aquosa do corante AP. Testes de adsorção de biodiesel foram feitos variando a proporção da mistura água/biodiesel e o tempo de adsorção pelos compósitos. O compósito com poliuretano/amido foi o que conseguiu uma maior substituição do polímero, 40%, seguido pela poliuretano/resíduo de mandioca, 23%, e poliuretano/celulose, somente 1,7% de adição, assim a celulose foi utilizada apenas como acréscimo do polímero. O pH 5 apresentou significativa remoção do corante e foi o pH escolhido para os estudos cinéticos e isotermas de adsorção. A caracterização evidenciou a maceração do resíduo de madeira, mostrou a remoção de lignina e hemicelulose, e a modificação da celulose foi comprovada pela presença dos picos da molécula de MDI; observou-se a semelhança entre o amido e resíduo de mandioca. O modelo que representou melhor os dados obtidos na cinética apontou para um material com propriedades características de adsorção do tipo quimissorção. O tempo de equilíbrio obtido para todos os compósitos foi de 8 h. Os compósitos com celulose modificada e com amido se ajustaram melhor ao modelo linear de Langmuir. Os compósitos com madeira tratada e com resíduo de mandioca se ajustaram melhor ao modelo linear de Freundlich. Para o biodiesel, a proporção que apresentou melhor adsorção foi a de 0,5:9,5 água:biodiesel e o tempo de equilíbrio foi de 16 h. Os resultados obtidos evidenciaram que todos os compósitos sintetizados apresentaram-se como materiais com boas propriedades adsortivas, mostrando-se alternativas viáveis à síntese de compósitos utilizando resíduos industriais para o tratamento de efluentes têxteis e biodiesel The goal of the present research was to develop composites in the foam form built of polyurethane, with the purpose of substituting the synthetic polymer used in the production of foams and test the adsorption against potential contaminants. The polymer was replaced by cassava starch and by industrial residues: wood residue and cassava residue. The adsorption was carried out with the textile dye Yellow Procion HE 4R (AP) and with biodiesel. The wooden residue was treated with maceration, obtaining cellulose, which was modified and used in the composites synthesis, as well as treated wood. The cellulose, modifiec cellulose, cassava starch and the cassava residue were characterized by FTIR, TGA and RMN 13C. The composites were submitted to adsorption tests with variation in pH, adsorption time and initial concentration of the aqueous solution of the AP dye. Biodiesel adsorption tests varying water:biodiesel proportions and adsorption times were made. The composite with polyurethane/cassava starch acheived greater substitution of the polymer, 40%, followed by polyurethane/cassava residue, with 23%, and polyurethane/cellulose, only 1,7% of addition, being used only as increas of the polymer. The pH 5 showed significant remotion and was chosed for the kinetic studies and adsortion isotherm. The characterization of the maceration of the wood residue, showed the remotion of lignin and hemicellulose, and the modification of cellulose was guaranteed by the presence of peaks of MDI mollecule; the resemblence between starch and cassava residue was observed. The model which best represented the obtained data in kinetic pointed to a material with properties characteristical to adsorption of the chemisorption. The obtained time of balance for all the composites was of 8 h. The composite with modifiec cellulose and with starch adjusted better to the linear model of Langmuir. The composite with wood treated and with cassava residue adjusted better to the linear model of Freundlich. For the biodiesel, the proportion which best presented adsorption was that of 0,5:9,5 water:biodiesel and the balance time was of 16 h. The results obtained prove that all the synthesized objects presented as materials with good adsorptive properties, showing viable alternatives to composite synthesis using industrial residue for the treatment of textile and biodiesel effluents
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- 2016
330. Análise direta de óleos vegetais brutos e refinados na forma de microemulsões para a determinação de ferro por espectrometria de absorção atômica em chama
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Galuch, Marília Bellanda, Garcia, Edivaldo Egea, Moraes, Juliana Carla Garcia, Monteiro, Johny Paulo, Universidade Estadual de Maringá, Centro de Ciências Exatas, Departamento de Química, and Programa de Pós-Graduação em Química
- Subjects
543.5 ,Óleos vegetais ,Espectrometria de absorção atômica ,Microemulsão - Óleo vegetal ,Química ,Ferro ,Ciências Exatas e da Terra - Abstract
Orientador: Prof. Dr. Edivaldo Egea Garcia Dissertação (mestrado em Química) - Universidade Estadual de Maringá, 2016 RESUMO: A concentração de ferro (Fe) está diretamente ligada à qualidade, estabilidade oxidativa, sabor, valor nutricional, e, principalmente, à toxicidade dos óleos vegetais. Mesmo que em baixas concentrações, a presença de Fe diminui a estabilidade oxidativa dos óleos e gorduras. Neste trabalho, foi proposto um método analítico rápido, simples, e de relativo baixo custo, para a análise direta de óleos vegetais brutos e refinados na forma de microemulsões para a determinação de Fe por espectrometria de absorção atômica em chama (FAAS). As microemulsões foram preparadas utilizando-se 250,0 µL de amostra de óleo vegetal, 4,40 mL de 1-propanol, 250,0 µL de Triton® X-100 e 100,0 µL de solução de HNO3 50% (v v-1). As microemulsões apresentaram estabilidade em termos de sinal analítico por, pelo menos, 3h. Durante a otimização do procedimento de calibração, foram testados quatro possíveis meios para a preparação das soluções de referência, selecionando-se o meio referente à solução composta por 4,65 mL de 1-propanol, 250,0 µL de Triton® X-100 e 100,0 µL de solução de HNO3 50% (v v-1) como meio de preparo das soluções padrão aquosas de Fe empregadas no procedimento de calibração externa. O método analítico proposto foi aplicado para a determinação da concentração total de Fe em amostras de óleos vegetais brutos e/ou refinados de milho, girassol, soja, canola, algodão e, também, de azeites de oliva extravirgens e refinados. As concentrações totais de Fe determinadas variaram de 2,72 ± 0,05 a 3,74 ± 0,11 mg kg-1, e as repetibilidades representadas como desvio padrão relativo (RSD) variaram de 1,8% a 5,2%. Os limites de detecção (LOD) e de quantificação (LOQ) obtidos para a determinação de Fe nas microemulsões das amostras de óleos vegetais foram de 0,020 mg L-1 e 0,066 mg L-1, respectivamente; e de 0,4 e 1,3 mg kg-1 de Fe em óleo, respectivamente. A exatidão dos resultados obtidos foi avaliada mediante a realização de experimentos de adição e recuperação, e as recuperações obtidas variaram de 84% a 105%, indicando exatidão adequada para a aplicação do método analítico proposto. ABSTRACT: The concentration of iron (Fe) is directly connected to the quality, oxidative stability, flavor, nutritional value and, mainly, to the toxicity of the vegetable oils. Even that in low concentrations the presence of iron decreases the oxidative stability of the fats and oils. In this work, was proposed a quick analytical method, simple, and of relative low cost to the direct analysis of crude and refined vegetable oils in the form of microemulsions to the determination of Fe by flame spectrometry of atomic absorption. The microemulsions were prepared using 250.0 µL of vegetable oil sample, 4.40 mL of 1-propanol, 250.0 µL of Triton® X-100 and 100.0 µL of HNO3 50% solution (v v-1). The microemulsions have shown stability in the terms of analytical sign of up to three hours, at least. During the optimization of the calibration procedure, were tested four possible mediums to the preparation of the reference solutions, selecting the medium relative to the solution composed by 4.65 mL of 1-propanol, 250.0 µL of Triton® X-100 and 100.0 µL of HNO3 50% solution (v v-1) as means of preparations of the aqueous standard solutions of Fe used in the procedure of external calibration. The analytical method proposed was applied to the determination of the concentration of Fe in crude and/or refined vegetable oils samples of corn, sunflower, soybean, canola, cottonseed and, also, of extra virgin and refined olive oils. The total concentrations determined of Fe varied from 2.72 ± 0.05 to 3.74 ± 0.11 mg kg-1, and the repeatability represented as relative standard deviation (RSD) varied from 1.8% to 5.2%. The limits of detection (LOD) and of quantification (LOQ) obtained to the determination of Fe in the microemulsion of the vegetable oil samples were of 0.020 mg L-1 and 0.066 mg L-1, respectively; and of 0.4 and 1.3 mg kg-1 of Fe in oil, respectively. The accuracy of the obtained results was evaluated by the realization of addition and recovery experiments, and the recuperations obtained varied from 84% to 105%, indicating properly accuracy for the application of the analytical method proposed. 56 f. : il. (algumas color).
- Published
- 2016
331. Quantificação em ácidos graxos, antioxidantes e desenvolvimento de metodologia para extração lipídica, em tecido muscular de peixes
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Montanher, Paula Fernandes, Jesuí Vergílio Visentainer [Orientador] - UEM, Prof. Dr. Jesuí Vergílio Visentainer, Makoto Matsushita - UEM, Juliana Carla Garcia Moraes - UEM, Elton Guntendorfer Bonafe - UTFPR, and Solange Maria Cottica - UTFPR
- Subjects
Cromatografia gasosa - Quantificação ,Metodologia de extração lipídica ,Esterificação - Ésteres metílicos de ácidos graxos ,Ácido Alfa-linolênico (LNA) ,Ácidos graxos - Análise química ,Peixes - Atividade antioxidante ,Química ,Ácidos graxos poliinsaturados ,Ciências Exatas e da Terra - Abstract
The aim of this study was to investigate the antioxidant capacity of hydrophilic and lipophilic extracts from fish muscle tissue, applying ORAC methodology Oxygen Radical Absorbance Capacity). A study of fatty acid composition and the development of a new method for total lipids extraction were also performed. This study was divided into four chapters, in which Chapter I is the review, Chapter II deals with the information related to the study of fatty acids and antioxidants incorporation in Nile tilapia (Oreochromis niloticus) fed with diet enriched in chia (Salvia hispanica) oil and avocado (Persea americana) peel extract. That study found an increase in total omega-3 fatty acids and antioxidant capacity of lipophilic fraction (L-ORAC(FL)) in treatments where there was the inclusion of chia oil after 45 days of feeding. In Chapter III a survey of antioxidant capacity and fatty acid composition of six fish species common in the southern brazilian coast was conducted. All species showed significant amounts of fatty acids eicosapentaenoic (EPA, 20: 5n-3) and docosahexaenoic (DHA, 22: 6n-3), a Person's correlation coefficient (r) of 0.72 was obtained between poly-unsaturated fatty acids and lipophilic antioxidant capacity. Chapter IV presents the proposed methodology for total lipids (TL) extraction from fish muscle tissue, using lower toxicity solvents, as an alternative methodology for Bligh & Dyer (1959). There was no statistical difference (p
- Published
- 2014
332. Desenvolvimento de modalidade cromatográfica baseada na identidade digital oxidativa de compostos orgânicos
- Author
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Kienen, Vanessa, Cláudio Celestino de Oliveira [Orientador] - UEM, Prof. Dr. Cláudio Celestino de Oliveira, Juliana Carla Garcia Moraes - UEM, Willian Ferreira da Costa - UEM, Altair Benedito Moreira - UNESP, and César Ricardo Teixeira Tarley - UEL
- Subjects
Cromatografia líquida ,Identidade digital oxidativa ,Processos oxidativos avançados - Reações de Fenton ,Química ,Sistema de análise por injeção sequencial - SIA ,Ciências Exatas e da Terra - Abstract
In this paper a new method based on chromatographic identididade digital oxidation of organic compounds has been developed enabling the separation and identification of organic compounds using liquid chromatography with spectrophotometric detectors. A sequential injection analysis (SIA) was used in conjunction with the Fenton reactions (Fe (II) and H2O2) to promote cleavage of organic compounds eluted from the chromatography column and how to manage the process of solid phase extraction for isolation/preconcentration, and re-introduction of the reaction products in the liquid chromatograph to obtain the identity oxidative. This approach combined liquid chromatography with photodiode array detectors (UV/ Vis) using the Fenton reactions for to promote the cleavage of compounds, allowing the development of a chromatographic of a method that is based on an initial separation of the organic constituents a sample by liquid chromatography followed by further separated after partial oxidation of the components of the sample, which achieves distinct peaks for the two chromatograms. First, original peaks of each sample constituent unoxidized and second, several peaks for each species should reflect that the previously formed products after the process of partial oxidation of the constituents of the sample, providing a set of data the products formed which was used to provide oxidative digital identity of each compound separately. At the end of the chromatographic process, the chromatograms provide information regarding the retention time of the analyte, which is related to the retention time of substances in standard solutions, UV/Vis spectrum of the compounds analysis (riboflavin and cyanocobalamin) , as well as signs of oxidation products for each species with their respective spectra and the relationship between the peak areas for each species formed which enabled the identification with higher reliability compounds analyzed. With the acquisition of digital identities of oxidative riboflavin and cyanocobalamin is possible to use the proposed method for the separation and identification of organic compounds that are eluted from a chromatographic column without the use of sophisticated and expensive equipment as the mass spectrometer and the nuclear magnetic resonance No presente trabalho uma nova modalidade cromatográfica baseada na identididade digital oxidativa de compostos orgânicos foi desenvolvida possibilitando a separação e identificação de substâncias orgânicas utilizando a cromatografia líquida com detectores espectrofotométricos. Para o desenvolvimento desta modalidade cromatográfica foi utilizado um sistema de análise por injeção sequencial (SIA - Sequential Injection Analysis) em conjunto com as reações de Fenton (Fe(II) e H2O2) para promover a clivagem de compostos orgânicos eluídos da coluna cromatográfica, bem como para gerenciar o processo de extração em fase sólida para isolamento/pré-concentração, e re-introdução dos produtos da reação no cromatógrafo líquido para obtenção da identidade oxidativa. Este método consiste na associação da cromatografia líquida com detectores espectrofométricos com arranjo fotodiodo (UV/Vis), utilizando as reações de Fenton para promover a clivagem dos compostos, possibilitando o desenvolvimento de uma modalidade cromatográfica que é baseada em uma primeira separação dos constituintes orgânicos de uma amostra por cromatografia líquida, seguida de nova separação após oxidação parcial dos componentes desta amostra, o que permite obter sinais distintos para os dois cromatogramas. No primeiro, os picos de cada constituinte da amostra não submetida ao processo de oxidação e no segundo, diversos picos para cada espécie analisada anteriormente que devem refletir os produtos formados após o processo de oxidação parcial dos constituintes da amostra, fornecendo um conjunto de dados relativos aos produtos formados que podem ser utilizados para fornecer a identidade digital oxidativa de cada composto separado. Ao final do processo cromatográfico, os cromatogramas fornecem informações a respeito do tempo de retenção dos analitos, que podem ser relacionados com o tempo de retenção de substâncias presentes em soluções padrão, os espectros na região UV/Vis dos compostos analisados (riboflavina e cianocobalamina), bem como os sinais dos produtos de oxidação para cada espécie com seus respectivos espectros e a relação entre as áreas dos picos para cada espécie formada o que permitiu identificar com maior confiabilidade os compostos analisados. Com a obtenção das identidades digitais oxidativas da riboflavina e da cianocobalamina é possível utilizar o método proposto na separação e identificação de compostos orgânicos que são eluidos de uma coluna cromatográfica sem recorrer ao uso de equipamentos sofisticados e de alto custo como o espectrômetro de massas e a ressonância magnética nuclear xx, 141 f.
- Published
- 2013
333. Optimization and validation of a method for the study of BTEX contamination in water, in the city of Maringa, employing extraction by headspace and Gas chromatography coupled to Mass spectrometry
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Batista, Aline Fontana, Willian Ferreira da Costa, Juliana Carla Garcia Moraes - UEM, and Gilberto Abate - UFPR
- Subjects
Paraná (Estado) ,Brasil ,Headspace extraction ,Cromatografia gasosa ,Química ,Análise ,Espectrometria de massa ,Headspace ,Ciências Exatas e da Terra ,Contaminação ,Paraná (State) ,Água subterrânea ,CG-EM ,GC-MS ,Maringá ,Contamination groundwater ,Brazil ,BTEX - Abstract
The aromatic compounds benzene, toluene, ethylbenzene and the isomeric xylene (BTEX) are among the major contaminants from groundwater due to leakages from underground storage tanks of fuel. These compounds released into the environment cause harm to human health. The present work was carried out to optimize, validate and implement a method of extraction "headspace" and gas chromatography coupled to mass spectrometry (HS-GC-MS) for the separation and determination of BTEX in water. The extraction parameters were evaluated by a fractional factorial design 24-1, where it was investigated the influence of temperature and extraction time, the volume of the liquid and the addition of potassium chloride (KCl) in the extraction of analytes. The extraction temperature and volume of the liquid were the factors that most influenced the response. The best conditions for extraction were: 80 °C, 30 min, 15.0 mL and 2.00 g of KCl. The method was validated in terms of linearity, limit of detection and quantification, precision and accuracy. The calibration curves showed good linearity with values r2>0.999. The detection limits were found to 0.0295, 0.0160, 0.0124, 0.0273 and 0.0142 μg L-1 for benzene, toluene, ethylbenzene, m, p-xylene and o-xylene, respectively. The method showed good precision where the relative standard deviations obtained for concentrations of 0.05 and 0.10 μg L-1 were less than 7.35 %, and concentration of 5.00 μg L-1 of less than 1.98 %. Accuracy was evaluated by recovery, in two concentration levels (0.10 and 5.00 μg L-1) which showed recoveries between 102 and 112 %. The method was applied in water samples from artesian wells near gas stations of fuel, in the city of Maringá-PR. Toluene was the analyte found in the largest number of samples analyzed (62.5 %), with concentrations ranging from 0.14 to 8.01 μg L-1. The levels of BTEX found in all samples were below the contamination limits imposed by national legislation. O presente trabalho consistiu em otimizar, validar e aplicar um método de extração por headspace e cromatografia em fase gasosa acoplada a espectrometria de massas (HS-GC-MS) para a separação e determinação de BTEX em água. Os parâmetros da extração foram avaliados por um planejamento fatorial fracionário 24-1, onde foram investigados a influência da temperatura e tempo de extração, do volume do líquido e da adição de cloreto de potássio (KCl) na extração dos analitos. A temperatura de extração e o volume do líquido foram os fatores que mais influenciaram na resposta. As melhores condições para a extração foram: 80 ºC, 30 min, 15,0 mL e 2,00g de KCl. O método foi validado em termos de linearidade, limite de detecção e quantificação, precisão e exatidão. As curvas analíticas apresentaram boa linearidade com valores de r2>0,999. Os limites de detecção encontrados foram de 0,0295; 0,0160; 0,0124; 0,0273 e 0,0142 μg L-1 para benzeno, tolueno, etilbenzeno, m,p-xileno, e o-xileno, respectivamente. O método apresentou boa precisão onde os desvios padrões relativos obtidos para as concentrações de 0,05 e 0,10 μg L-1 foram menores que 7,35 %, e para concentração de 5,00 μg L-1 menores que 1,98 %. A exatidão foi avaliada pelo ensaio de recuperação, em dois níveis de concentração (0,10 e 5,00 μg L-1) que apresentaram recuperações entre 102 a 112 %. O método foi aplicado em amostras de água de poços artesianos próximos a postos revendedores de combustível, na cidade de Maringá-PR. O tolueno foi o analito encontrado no maior número de amostras analisadas (62,5 %), com concentração variando de 0,14 a 8,01 μg L-1. Os teores de BTEX encontrados em todas as amostras estudadas estavam abaixo dos limites de contaminação impostos pela legislação nacional. ix, 57 f
- Published
- 2013
334. Análise por injeção em fluxo para determinação da capacidade antioxidante total de vinhos utilizando o método DPPH : otimização das condições a partir metodologia de superfície de resposta
- Author
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Bukman, Lais, Vitor de Cinque Almeida, Juliana Carla Garcia Moraes - UEM, and Ailey Aparecida Coelho Tanamati - UTFPR
- Subjects
Análise por injeção em fluxo ,Atividade antioxidante ,Vinho ,Brasil ,Response surface methodology ,Antioxidant activity ,Metodologia de superfície de resposta ,Flow injection analysis ,Wine ,Química ,Brazil ,Ciências Exatas e da Terra - Abstract
Antioxidants are substances that react with free radicals stabilizing and preventing their harmful actions to the organism and are present in a wide variety of foods and beverages. Due to importance of antioxidant activity in the some foods, several analytical methods have been proposed among them include FRAP, ORAC, total polyphenol content and DPPH methods. The main objective of this study is to propose an analytical methodology using a flow injection analysis system (FIA), with a merging zones configuration, for determination of total antioxidant activity by DPPH radical scavenging assay. The FIA system conditions were optimized with the response surface methodology using the central composite rotatable design. The optimization parameters studied were: the carrier flow rate, the lengths of the sample and reagent loops and the length of the reactor. According to the results, levels of selected parameters were: carrier flow rate 1.12 mL min-1, length of the loops 18.5 cm and length of the reactor 234.6 cm. The detection and quantification limits were, respectively, 2.647 and 8.824 μ mol L-1 acid galic / mL wine. The proposed method had an analytical frequency of 41 samples per hour and a 58% saving in the consumption of reagent DPPH and 62.6% in the consumption of carrier agent methanol compared to the conventional method. The DPPH assay adapted to the FIA system under the optimization conditions was utilized to determine the antioxidant activity of wine samples. Os antioxidantes são substâncias que reagem com os radicais livres estabilizando e impedindo suas ações maléficas ao organismo e estão presentes em uma grande variedade de alimentos e bebidas. Devido à importância da atividade antioxidante em alimentos, vários métodos analíticos têm sido propostos, dentre os quais incluem o método FRAP, ORAC, Fenólicos Totais e o DPPH. O objetivo principal do trabalho foi propor uma metodologia analítica utilizando um sistema de análise por injeção em fluxo (FIA), com configuração de zonas coalescentes, para determinação da atividade antioxidante total por captura do radical DPPH. As condições do sistema FIA foram otimizadas através da metodologia de superfície de resposta usando um planejamento fatorial composto central rodável (PFCCR). Os parâmetros de otimização estudados foram: fluxo do transportador, comprimento das alças de amostragem e do reagente e comprimento do reator. De acordo com os resultados, os níveis dos parâmetros selecionados foram: fluxo de 1,12 mL min-1, comprimento das alças de 18,5 cm e comprimento do reator de 234,6 cm. Os limites de detecção e quantificação foram 2,647.10-6 e 8,824.10-6 mol L-1 ácido gálico / mL de vinho. O método proposto apresentou freqüência analítica de 41 análises por hora e uma economia de 58% no consumo do reagente DPPH e 62,60% no consumo do agente transportador metanol em comparação com o método convencional. O ensaio DPPH adaptado ao sistema FIA de zonas coalescentes, nas condições otimizadas foi utilizado para determinar a atividade antioxidante total de amostras de vinho. [7] viii, 57 f
- Published
- 2012
335. Prevalence of Cryptococcal Antigenemia and Lateral Flow Assay Accuracy in Severely Immunosuppressed AIDS Patients.
- Author
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Negri ACG, Nunes MO, Lima GME, Venturini J, de Oliveira SMDVL, Lazera MDS, Carvalho LR, Chang MR, Tsujisaki RAS, França AO, Mendes RP, and Paniago AMM
- Abstract
This study aimed to estimate the prevalence of cryptococcal antigenemia detected by lateral flow assay (LFA) in AIDS patients and its accuracy in the diagnosis of cryptococcosis. Conducted at a university hospital in Brazil from March 2015 to July 2017, it included AIDS patients over 18 years old with a CD4+ count ≤ 200 cells/mm
3 . Cryptococcal antigen (CrAg) detection using LFA and latex agglutination (LA), along with blood and urine cultures, were performed. The reference standard was the identification of Cryptococcus spp. in clinical specimens through microbiological or histopathological examination. Among 230 patients, the prevalence of CrAg detected by LFA (CrAg LFA) was 13.0%. Factors associated with cryptococcal antigenemia included fever, vomiting, seizures, and a lack of antiretroviral therapy. The sensitivity and specificity of CrAg LFA were 83.9% and 98.0%, respectively. The positive predictive value (PPV) was 86.7%, the negative predictive value (NPV) was 97.5%, and overall accuracy was 96.1%. Cross-reactions were observed in patients with histoplasmosis and paracoccidioidmycosis, but not with aspergillosis or positive rheumatoid factor. The study concludes that the LFA is a useful tool for detecting cryptococcal antigenemia in severely immunocompromised AIDS patients due to its high NPV, specificity, and PPV.- Published
- 2024
- Full Text
- View/download PDF
336. Treatment of mixed depression with theta-burst stimulation (TBS): results from a double-blind, randomized, sham-controlled clinical trial.
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Tavares DF, Suen P, Rodrigues Dos Santos CG, Moreno DH, Lane Valiengo LDC, Klein I, Borrione L, Marques Forte P, Brunoni AR, and Alberto Moreno R
- Subjects
- Adult, Canada, Depression, Humans, Treatment Outcome, Depressive Disorder, Major therapy, Transcranial Magnetic Stimulation
- Abstract
Mixed depression is probably different in terms of clinical course and response to treatment. Repetitive transcranial magnetic stimulation (rTMS) is well established in non-mixed depression, and theta-burst stimulation (TBS) protocol is replacing conventional protocols because of noninferiority and reduced delivery time. However, TBS has not been adequately studied in mixed states. This study was a double-blind, six-week, sham-controlled, and randomized clinical trial of bilateral TBS targeting the right and left dorsolateral prefrontal cortex, respectively. Adults with bipolar and major depressive disorder experiencing an acute mixed depression were eligible if they had not benefited from a first- or second-line treatment for acute unipolar or bipolar depression recommended by the Canadian Network for Mood and Anxiety Treatments. Out of 100 patients included, 90 composed modified intention-to-treat sample, which was patients that completed at least one week of the intervention. There were no significant differences in Montgomery-Asberg depression rating scale score changes (least squares mean difference between groups at week 3, -0.06 [95% CI, - 3.39 to 3.51; P = 0.97] in favor of sham TBS). Response and remission rates per MADRS were also not statistically different among active and sham groups (35.7% vs. 43.7%, and 28.5% vs. 37.5% respectively at week 6, ps > 0.51). No other analyses from baseline to weeks 3 or 6 revealed significant time x group interaction or mean differences among groups in the mITT sample. Bilateral TBS targeting the DLPFC is not efficacious as an add-on treatment of acute bipolar and unipolar mixed depression. ClinicalTrials.govIdentifier: NCT04123301., (© 2021. The Author(s), under exclusive licence to American College of Neuropsychopharmacology.)
- Published
- 2021
- Full Text
- View/download PDF
337. COVID-19: repercussions of nursing, structuring and resolutivity of national health systems.
- Author
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Ramos AR, Bottega CG, Petersen LL, Rollo RM, Marchioro MK, and Rocha CMF
- Subjects
- Health Systems Plans, Humans, Pandemics, SARS-CoV-2, COVID-19, Delivery of Health Care, Nursing Care
- Abstract
Aim: To analyze the repercussions of Nursing, the structuring and resolution of National Health Systems in facing the new coronavirus (SARS-CoV-2) in selected countries., Method: Reflection article on the confrontation of COVID-19 by the National Health Systems of China, United States of America, Italy, United Kingdom, Portugal, Cuba and Brazil, from information disseminated in different media and in the literature., Results: The response of health systems depended more on political decisions than on their structuring and organization. Nursing, being the front line, was the profession most affected in number of cases and deaths., Final Considerations: The reflection shows that the countries' economic and political issues interfered in the response to COVID-19 and what the role played by Nursing is essential in the front line to face the pandemic.
- Published
- 2021
- Full Text
- View/download PDF
338. Efficacy, Safety, and Tolerability of Theta-Burst Stimulation in Mixed Depression: Design, Rationale, and Objectives of a Randomized, Double-Blinded, Sham-Controlled Trial.
- Author
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Tavares DF, Dos Santos CGR, Valiengo LDCL, Klein I, Borrione L, Forte PM, Brunoni AR, and Moreno RA
- Abstract
Introduction: Mixed-specifier mood disorders are probably a different subgroup in terms of response to treatment, socio-demographic parameters, course, and family history. Here we describe the rationale and design of a clinical trial aimed to test the efficacy, safety, and tolerability of a non-pharmacological treatment known as theta-burst stimulation (TBS) for treating the mixed depressive episodes of both bipolar (I or II), and unipolar depression., Methods: The study is designed as a randomized, sham-controlled, double-blinded clinical trial evaluating TBS for the treatment of moderate or severe major depressive episodes with mixed features of patients receiving at least one first or second-line pharmacological treatment for depressive episodes without adequate response. Ninety adult (18 to 65 years old) patients will be enrolled and submitted to 6-week (comprising 5 consecutive days a week sessions for the first 3 weeks and then 2 days a week for a further 3 week) of inhibitory followed by excitatory TBS in dorsolateral prefrontal cortex. Participants will be assessed using clinical and neuropsychological tests before and after the intervention. The primary outcome is change in Montgomery-Åsberg Depression Scale (MADRS) score over time and across groups. Cognitive parameters will also be assessed with neuropsychological tests., Results: The clinical results will provide evidence about TBS as an adjunctive treatment for mixed depression treatment and neuropsychological parameters will contribute toward an improved understanding the effects of TBS in cognition., Conclusion: Our results could introduce a novel therapeutic technique for mixed depressive episodes of both bipolar and unipolar disorders., Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT04123301; date of registration: 10/10/2019; URL: https://clinicaltrials.gov/ct2/show/NCT04123301?term=NCT04123301&rank=1., (Copyright © 2020 Tavares, dos Santos, Valiengo, Klein, Borrione, Forte, Brunoni and Moreno.)
- Published
- 2020
- Full Text
- View/download PDF
339. Monitoring practices in municipal healthcare management and their interface with nursing.
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Reuter CLO, Santos VCFD, Bottega CG, and Roese A
- Subjects
- Brazil, Decision Support Systems, Management, Health Personnel, Health Plan Implementation, Health Planning, Humans, Interviews as Topic, Program Evaluation, Qualitative Research, Quality Assurance, Health Care methods, Quality Improvement organization & administration, Community Health Services organization & administration, Health Facility Administrators psychology, Nursing organization & administration, Quality Assurance, Health Care organization & administration, Urban Health
- Abstract
Objective: To analyse the healthcare monitoring practices of the local government and its interfaces with nursing., Methods: This is a descriptive, exploratory, and qualitative study conducted in six municipalities in the 10th health region of the state of Rio Grande do Sul. Data were collected through semi-structured interviews with six healthcare managers and one adviser, and subjected to content analysis., Results: The results led to the final categories, "Monitoring practices in municipal healthcare management" and "Difficulties of managers in implementing monitoring"., Conclusion: The managers pointed out potentialities and weaknesses in the monitoring practices of municipal healthcare. This process is critical for the practice of healthcare workers, especially nurses, since it encourages the use of new tools and innovations that support decision making.
- Published
- 2017
- Full Text
- View/download PDF
340. Pertussis in the central-west region of Brazil: one decade study.
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Druzian AF, Brustoloni YM, Oliveira SM, Matos VT, Negri AC, Pinto CS, Asato S, Urias Cdos S, and Paniago AM
- Subjects
- Adolescent, Age Distribution, Brazil epidemiology, Child, Child, Preschool, Female, Humans, Infant, Male, Vaccination statistics & numerical data, Whooping Cough prevention & control, Disease Outbreaks, Whooping Cough epidemiology
- Abstract
In many parts of the world, numerous outbreaks of pertussis have been described despite high vaccination coverage. In this article we report the epidemiological characteristics of pertussis in Brazil using a Surveillance Worksheet. Secondary data of pertussis case investigations reported from January 1999 to December 2008 recorded in the Information System for Notifiable Diseases (SINAN) and the Central Laboratory for Public Health (LACEN-MS) were utilized. The total of 561 suspected cases were reported and 238 (42.4%) of these were confirmed, mainly in children under six months (61.8%) and with incomplete immunization (56.3%). Two outbreaks were detected. Mortality rate ranged from 2.56% to 11.11%. The occurrence of outbreaks and the poor performance of cultures for confirming diagnosis are problems which need to be addressed. High vaccination coverage is certainly a good strategy to reduce the number of cases and to reduce the impact of the disease in children younger than six months., (Copyright © 2013 Elsevier Editora Ltda. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
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