Síntese enzimática de ésteres de açúcar: surfactantes e polímeros como novos materiais ambientalmente seguros

Sugar esters are substances which possess surfactant, antifungical and bactericidal actions and can be obtained through two renewable sources of raw materials: sugars and vegetable oils. Their excellent biodegradability, allied to lhe fact that they are non toxic, insipid, inodorous, biocompatible, no-ionic, digestible and because they can resist to adverse conditions of temperature, pH and salinity, explain lhe crescent use of these substances in several sections of lhe industry. The objective of this thesis was to synthesize and characterize surfactants and polymers containing sugar branched in their structures, through enzymatic transesterification of vinyl esters and sugars, using alkaline protease from Bacillus subtilis as catalyst, in organic medium (DMF).Three types of sugars were used: L-arabinose, D-glucose and sucrose and two types of vinyl esters: vinyl laurate and vinyl adipate. Aiming to reach high conversions from substrates to products for a possible future large scale industrial production, a serie of variables was optimized, through Design of Experiments (DOE), using Response Surface Methodology (RSM).The investigated variables were: (1) enzyme concentration; (2) molar reason of substrates; (3) water/solvent rale; (4) temperature and (5) time. We obtained six distinct sugar esters: 5-0-lauroyl L-arabinose, 6-0-lauroyl D-glucose, 1'-O-lauroyl sucrose, 5-0-vinyladipoyl L-arabinose, 6-0-vinyladipoyl D-glucose and 1 '-O-vinyladipoyl sucrose, being lhe last three polymerizable. The progress of lhe reaction was monitored by HPLC analysis, through lhe decrease of sugar concentration in comparison to lhe blank. Qualitative analysis by TLC confirmed lhe formation of lhe products. In lhe purification step, two methodologies were adopted: (1) chromatographic column and (2) extraction with hot acetone. The acylation position and lhe chemical structure were determined by 13C-RMN. The polymerization of lhe three vinyl sugar esters was possible, through chemical catalysis, using H2O2 and K2S2O8 as initiators, at 60°C, for 24 hours. IR spectra of lhe monomers and respective polymers were compared revealing lhe disappearance of lhe vinyl group in lhe polymer spectra. The molar weights of lhe polymers were determined by GPC and presented lhe following results: poly (5-0-vinyladipoyl L-arabinose): Mw = 7.2 X 104; PD = 2.48; poly (6-0-vinyladipoyl D-glucose): Mw = 2.7 X 103; PD = 1.75 and poly (1'-O-vinyladipoyl sucrose): Mw = 4.2 X 104; PD = 6.57. The six sugar esters were submitted to superficial tension tests for determination of the critical micelle concentrations (CMC), which varied from 122 to 167 ppm. Finally, a study of applicability of these sugar esters, as lubricants for completion fluids of petroleum wells was' accomplished through comparative analysis of lhe efficiency of these sugar esters, in relation to three commercial lubricants. The products synthesized in this thesis presented equivalent or superior action to lhe tested commercial products

Sinterização de matrizes cerâmicas à base de alumina reforçadas por carbetos a partir de precursores poliméricos

Ceramic composites produced with polymerics precursors have been studied for many years, due to the facility of obtaining a complex shape, at low temperature and reduces cost. The main objective of this work is to study the process of sintering of composites of ceramic base consisting of Al2O3 and silicates, reinforced for NbC, through the technique of processing AFCOP, as well as the influence of the addition of LZSA, ICZ and Al as materials infiltration in the physical and mechanical properties of the ceramic composite. Were produced ceramic matrix composites based SiCxOy e Al2O3 reinforced with NbC, by hidrosilylation reaction between D4Vi and D1107 mixtured with Al2O3 as inert filler, Nb and Al as reactive filler. The specimens produced were pyrolised at 1200, 1250 and 1400°C and infiltred with Al, ICZ and LZSA, respectively. Density, porosity, flexural mechanical strength and fracture surface by scanning electron microscopy were evaluated. The microstructure of the composites was investigated by X-ray diffraction to identify the presence of crystalline phases. The composites presented apparent porosity varying of 31 up to 49% and mechanical flexural strength of 14 up to 34 MPa. The infiltration process improviment of the densification and reduction of the porosity, as well as increased the values of mechanical flexural strength. The obtained phases had been identified as being Al3Nb, NbSi2, Nb5S3, Nb3Si and NbC. The samples that were submitted the infiltration process presented a layer next surface with reduced pores number in relation to the total volume

Frecuencia de interopatógenos infecciosos en diarreas agudas de menores de cinco años. Centros de salud del cantón Cuenca. 2002-2003

A traves de la presente investigación se determinó la frecuencia de los enteropatógenos en diarreas agudas en niños menores de cinco años del cantón Cuenca-Ecuador y su relación con la edad, sexo y residencia; la muestra fue de 1.000 niños que asistieron a seis Centros de Salud desde mayo hasta noviembre de 2002. Se utilizó el método descriptivo; esta investigación constituye una primera fase de otro que esta en curso y que trata de determinar los factores de riesgo a la infección. Este trabajo fue aprobado por el Comité de Etica de la Facultad de Ciencias Médicas de la Universidad de Cuenca y el consentimiento informado se recibió de manera verbal. Los exámenes se realizaron en el laboratorio de Microbiología de esta Facultad se utilizó microscopía directa simple y por concentración para protozoarios y helmintos; coloración de Ziehl Neelsen modificado para Criptosporidium; Coprocultivo y pruebas bioquímicas para el diagnóstico de Salmonellas y Shigellas, a más de la prueba de aglutinación en látex para E.C.E.P y Rotavirus. Los enteropatógenos estan presentes en el 46 por ciento de las diarreas agudas; existe mono infección en le 7.9 por ciento; poli infección en el 38.1 por ciento; los agentes asociados a diarrea aguda son: Giardia lamblia 16 por ciento Rotavirus, 13.9 por ciento ECEP, 8.3 por ciento Criptosporídium 3.3 por ciento Salmonellas, 1.9 por ciento y Shigellas, 1.9 por ciento. La mayor frecuencia de enteropatógenos se produce entre los 49-60 meses 56.7 por ciento]; en el sexo femenino 246/524 [46.9 por ciento] en el área rural 186/326 [56.9 por ciento]

Prevalencia de parasitismo en los niños del Centro de Apoyo Nutricional y Pedagógico Santo Hermano Mguel. Cuenca septiembre 2015 - enero 2016

Antecedentes. Las enfermedades provocadas por parásitos, constituyen problemas serios de salud en la población, presentan una alta incidencia de infección por parásitos intestinales, Objetivo: Determinar la prevalencia de parasitismo en los niños del Centro de Apoyo Nutricional y Pedagógico Santo Hermano Miguel. Cuenca Septiembre 2015 - Enero 2016. Método y materiales: Se realizó un estudio de tipo descriptivo de corte transversal. Se trabajó con una población infantil de 100 niños que va entre 5 a 11 años. Los resultados obtenidos tuvieron un uso confidencial exclusivamente para fines de investigación y fueron analizados mediante software SPSS 15 y Excel. Resultados: El 25% de la población infantil es del género masculino, y el 75 % femenino, de los cuales el 80% presenta parasitismo, el 65% mono parasitismo y el 35% poli parasitismo. Las especies patógenas observadas son: Entamoeba histolytica 85%, Giardia lamblia 3,8%, Trichomona intestinalis 1,3% y Taenia saginata 2,5%.Según las características socioeconómicas, el 100% de la población consume agua potable. El 83% se lavan las manos antes de comer, el 71% lava las frutas antes de consumirlas, el 100% utiliza el servicio sanitario, a su vez el 42% presentan dolor abdominal, el 12% presentan diarrea, el 14% tiene prurito anal y el 46% tiene falta de apetito. Conclusiones: Los hábitos de higiene personal y de alimentación no se están llevando de la forma correcta por ello existe un porcentaje alto de parasitismo, por más que se cuente con los servicios básicos, esto no garantiza un parasitismo negativo

Papel del inmunogen isg15 de lubina (Dicentrarchus labrax) en las infecciones por betanodavirus

En peces, al igual que en vertebrados superiores, la respuesta antiviral innata está mediada por el sistema interferón tipo I (IFN I), que actúa mediante la activación de genes denominados isg (interferon-stimulated genes), entre los que se incluye el gen isg15. La proteína codificada por este gen, denominada ISG15, presenta actividad antiviral actuando como citoquina, o mediante un mecanismo denominado ISGilación, que consiste en su unión covalente a proteínas víricas o celulares. Entre las enfermedades de etiología viral que afectan a la lubina (Dicentrarchus labrax), destaca la necrosis nerviosa viral, causada por el virus de la necrosis nerviosa (NNV, género Betanodavirus), que presenta dos segmentos de ARN monocatenario de polaridad positiva: ARN1 (polimerasa viral) y ARN2 (proteína de la cápside). Las diferencias en la secuencia de la región variable T4 del segmento ARN2 permiten su clasificación en 4 genotipos, siendo el genotipo RGNNV el único asociado a episodios de elevada mortalidad en lubina. El presente estudio contribuye a ampliar el conocimiento del papel del sistema IFN I en lubina frente a infecciones por betanodavirus, describiéndose la estructura del gen isg15, analizando su transcripción en respuesta a poli I:C y RGNNV; y evaluando su actividad in vitro. La lubina presenta un gen isg15, compuesto por dos exones y un intrón localizado en la región 5’-UTR. El ORF, de 474 pb, codifica una proteína de 157 aminoácidos constituida por dos dominios tipo ubiquitina y un motivo RLRGG en el extremo carboxilo terminal. La clonación del ORF en el plásmido pcDNA His/Max, y su posterior transfección en la línea celular E-11, ha permitido obtener una línea celular estable (DLISG15-E11), en la que se ha demostrado, mediante inmunofluorescencia indirecta, la localización citoplasmática de esta proteína. El análisis de transcripción muestra una respuesta más temprana e intensa tras la inducción por poli I:C que por RGNNV. Poli I:C estimula la expresión génica desde las 4 hasta las 24 h post-inyección (p.i.) en ambos órganos, y con una cinética similar. Sin embargo, ambos órganos difieren en el nivel de transcripción del gen tras la infección por RGNNV, produciéndose una estimulación temprana, desde las 12 h p.i., y de mayor nivel en el cerebro que en el riñón cefálico, órgano en el que la expresión comienza a las 72 h p.i. La actividad antiviral se ha evaluado mediante el análisis comparativo de la replicación de RGNNV, determinada mediante PCR cuantitativa, en células DLISG15-E11 y células control no transfectadas, no observándose diferencias significativas. Sin embargo, ISG15 podría actuar a otro nivel del ciclo de multiplicación viral, por lo que se están realizando ensayos de rendimiento vírico extracelular mediante titulación, y de ISGilación mediante Western-blot. El hecho de que el cerebro sea el principal órgano diana para la multiplicación de betanodavirus, y el papel antiviral atribuido a la ISG15, junto con los resultados obtenidos, contribuyen a dilucidar la importancia de este gen frente a las infecciones por RGNNV en lubina, incrementándose el conocimiento del papel del sistema del IFN I en la defensa frente a las infecciones vírcas y la relación patógeno-hospedador.

Turismo de Favela y Seguridad “La puesta en valor del Turismo Justo como herramienta para el desarrollo turístico sostenible del Museo a cielo abierto de la Favela da Providência en Rio de Janeiro

Esta investigación realiza una observación etnográfica profunda a uno de los programas más exitosos de Turismo de Favela en Rio de Janeiro, los esfuerzos para el controle de la violencia y para la sostenibilidad del Turismo Justo como forma de incluir los habitantes de la comunidad entre los actores de esto destino peculiar denominado Favela da Providência. A partir del análisis de esta experiencia, se buscan extraer líneas de acción que permitan generar nuevas políticas para el controle de la violencia en áreas marginales y acciones que incluyen los habitantes de las Favelas en la actividad turística. Este trabajo presupone, por ende, una exhaustiva descripción de las dinámicas sociales al interior de esta comunidad, de su configuración histórica, de sus espacios y actores, y de las condiciones socio-culturales que permitieron el éxito y manutención de este proceso de desarrollo turístico Sostenible.

Análise proteômica de células não fagocíticas na fase inicial da infecção por trypanosoma cruzi

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Medicina, Programa de Pós-Graduação em Patologia Molecular, 2015.

Síntese e caracterização de nanocompósitos magnéticos empregando polimerização radicalar em meios homogêneo (blk) e heterogêneo (miniemulsão)

Tese (doutorado)—Universidade de Brasília, Instituto de Química, Curso de Pós-Graduação em Química, 2016.

Otia sive ephemerides felsineae recentiores /

Mezzavacca (d. 1704), professor of jurisprudence at Bologna and later governor of a town near Venice, was a self-taught astronomer. This series of celestial ephemerides continues the ones begun by Montebruni.

Crescimento e estruturas do sistema digestório de larvas de pacu alimentadas com dieta microencapsulada produzida experimentalmente

Foram comparados os efeitos de diferentes dietas e da transição alimentar sobre o desempenho zootécnico e a morfologia do trato digestório de larvas de pacu alimentadas com duas dietas comerciais e uma dieta experimental microencapsulada produzida por gelificação interna. Larvas com quatro dias de vida receberam os seguintes protocolos alimentares: somente náuplios de artêmia em quantidades crescentes (controle positivo); larvas mantidas em jejum (controle negativo); três tipos de alimento formulado durante todo o experimento (dieta experimental microencapsulada, dieta comercial NRD1.2/2.0, Inve, USA, e dieta Poli-Peixe 450F, PoliNutri, Brasil); e três protocolos de transição alimentar com náuplios de artêmia durante os seis primeiros dias, seis dias de coalimentação, e somente as respectivas dietas formuladas após esse período. O experimento foi conduzido por 23 dias em delineamento inteiramente casualizado, com avaliações periódicas do crescimento e do sistema digestório. A taxa de sobrevivência foi determinada ao final do experimento. Os melhores desempenhos de crescimento e sobrevivência, assim como mais acelerada organogênese do sistema digestório, foram verificados entre os animais que receberam alimento vivo. As larvas que passaram pela transição alimentar apresentaram médias intermediárias de crescimento e sobrevivência e não diferiram entre si. Entre os grupos que receberam apenas dieta inerte, somente naquele alimentado com a dieta nacional houve sobrevivência até o final do experimento. Nenhuma das dietas formuladas é adequada para uso como alimento exclusivo para larvas de pacu. Na fase de transição alimentar, a dieta experimental microencapsulada proporciona resultados de sobrevivência e crescimento semelhantes aos obtidos com dietas comerciais.

Filmes formados pelo copolímero SEBS e nanopartículas de óxidos de ferro : preparação e caracterização

Dissertação (mestrado)—Universidade de Brasília, Instituto de Física, Programa de Pós-Graduação em Física, 2016.

Petrografia, geoquímica e geocronologia das rochas metavulcânicas e metaplutônicas dos Greenstone Belts faina e Serra de Santa Rita : implicações para o ambiente tectônico

Dissertação (mestrado)—Universidade de Brasília, Instituto de Geociências, Pós-Graduação em Geologia, 2016.

The prevalence and characteristics associated with excessive daytime sleepiness among Australian workers

OBJECTIVE: To estimate the prevalence of excessive daytime sleepiness (EDS) and its associated factors in a mixed population of employed Australian workers. METHODS: Study participants (n = 707) were volunteers from various Melbourne workplaces, participating in a workplace physical activity program in 2008. Daytime sleepiness was assessed using the Epworth Sleepiness Scale (ESS), with EDS defined as ESS scores >10. RESULTS: In this population of adult employees (40.0% male; mean age 40.2 ± 10.4 years), prevalence of EDS was 16.0%. Characteristics associated with EDS and higher ESS scores were age, higher body mass index, markers of poorer diet, and markers of poorer mental health. CONCLUSIONS: Excessive daytime sleepiness is potentially an important contributor to lower productivity and poorer mental health in the workplace. Our finding suggests that workplace health programs aimed at improving diet and body weight may also help alleviate EDS.

Change in well-being amongst participants in a four-month pedometer-based workplace health program

BACKGROUND: There is increasing uptake of workplace physical activity programs to prevent chronic disease. While they are frequently evaluated for improvement in biomedical risk factors there has been little evaluation of additional benefits for psychosocial health. We aimed to evaluate whether participation in a four-month, team-based, pedometer-based workplace health program known to improve biomedical risk factors is associated with an improvement in well-being, immediately after the program and eight-months after program completion.

METHODS: At baseline (2008), 762 adults (aged 40 ± 10 SD years, 42% male) employed in primarily sedentary occupations and voluntarily enrolled in a physical activity program were recruited from ten Australian worksites. Data was collected at baseline, at the completion of the four-month program and eight-months after program completion. The outcome was the WHO-Five Well-being Index (WHO-5), a self-administered five-item scale that can be dichotomised as 'poor' (less than 52%) or 'positive' (more than or equal to 52%) well-being.

RESULTS: At baseline, 75% of participants had positive well-being (mean: 60 ± 19 SD WHO-5 units). On average, well-being improved immediately after the health program (+3.5 units, p < 0.001) and was sustained eight-months later (+3.4 units from baseline, p < 0.001). In the 25% with poor well-being at baseline, 49.5% moved into the positive well-being category immediately after program completion, sustained eight-months later (p < 0.001).

CONCLUSIONS: Clinically relevant immediate and sustained improvements in well-being were observed after participation in the health program. These results suggest that participation in workplace programs, such as the one evaluated here, also has the potential to improve well-being.

Eight month post program completion: change in risk factors for chronic disease amongst participants in a four-month pedometer workplace health program

Objective: To evaluate whether participation in a 4-month, pedometer-based, physical activity, workplace health program is associated with long-term sustained improvements in risk factors for type 2 diabetesand cardiovascular disease, 8 months after the completion of the program.Design and Methods: A sample size of 720 was required. 762 Australian adults employed in primarily sedentary occupations and voluntarily enrolled in a workplace program were recruited. Demographic, behavioral, anthropometric and biomedical measurements were completed at baseline, 4 and 12 months.Results: About 76% of participants returned at 12 months. Sustained improvements at 12 months were observed for self-reported vegetable intake, self-reported sitting time and independently measured bloodpressure. Modest improvements from baseline in self-reported physical activity and independently measured waist circumference at 12 months indicated that the significant improvements observed immediately after the health program could not be sustained. Approximately half of those not meetingguidelines for physical activity, waist circumference and blood pressure at baseline, were meeting guidelines at 12 months.Conclusions: Participation in this 4-month, pedometer-based, physical activity, workplace health program was associated with sustained improvements in chronic disease risk factors at 12 months. These results indicate that such programs can have a long-term benefit and thus a potential role to play in population prevention of chronic disease.