Uso do pó da palha de carnaúba em compósitos de quitosana

In this work a biodegradable composite using the carnauba straw s powder as reinforcement on chitosan matrix polymeric were manufactured. Firstly, were carried out the chemistry characterization of the carnauba straw s powder before and after treatments with NaOH and hexane. Goering and Van Soest method (1970), flotation test, moisture absorption, FTIR, TG/DTG, DSC and SEM have also being carried out. Composites were developed with variations in granulometry and in powder concentrations. They were characterized by TG/DTG, SEM and mechanicals properties. The results of chemical composition showed that the carnauba straw s powder is composed of 41% of cellulose; 28,9% of hemicellulose and 14% of lignin.The flotation test have indicated that the chemical treatment with NaOH decreased the powder s hidrophilicity.The thermal analysis showed increased of thermal stability of material after treatments. The results of FTIR and SEM revealed the removal of soluble materials from the powder (hemicelluloses and lignin), the material became rougher and clean. The composites obtained showed that the mechanicals properties of the composites were decreased in respect at chitosan films, and the composites with the powder at 150 Mesh showed less variation in the modulus values. The speed test of 10 mm/min showed the better reproducibility of the results and is in agreement to the standard ASTM D638. The SEM analysis of fracture showed the low adhesion between the fiber/matrix. The increase of volume of powder in the composite caused a decrease in values of stress and strain for the samples with untreated powder and treated with hexane. The composite with 50% of the powder s treated in NaOH didn t have significant variation in the values of stress and strain as compared with the composites with 10% of the powder, showing that the increase in the volume of fiber didn t affect the stress and strain of the composite. Thereby, it is concluded that the manufacture of polymeric composites of chitosan using carnauba straw s powder can be done, without need for pre-treatment of reinforcement, become the couple of carnauba straw s powder-chitosan a good alternative for biodegradable composites

Estudo da potencialidade da espectroscopia de infravermelho próximo na análise de cabelo utilizando ferramentas quimiométricas para diferenciar fumantes de não fumantes

This paper investigates the potential of near infrared spectroscopy (NIR) for forensic analysis of human hair samples in order to differentiate smokers from nonsmokers, using chemometric modeling as an analytical tool. We obtained a total of 19 hair samples, 9 smokers and 10 nonsmokers varying gender, hair color, age and duration of smoking, all collected directly from the head of the same great Natal-RN. From the NIR spectra obtained without any pretreatment of the samples was performed an exploratory multivariate chemical data by applying spectral pretreatments followed by principal component analysis (PCA). After chemometric modeling of the data was achieved without any experimental data beyond the NIR spectra, differentiate smokers from nonsmokers, by demonstrating the significant influence of tabacco on the chemical composition of hair as well as the potential of the methodology in forensic identification

Vinculando a etnoictiologia às evidências biológicas para explicar o declínio da riqueza da ictiofauna neotropical

The diversity of fish species from South America has been affected by various anthropogenic practices. Some studies have reported the influence that illegal transferring or introduction of exotic species have on the trophic webs of continental lakes. The loss of diversity on fish populations and consequent impacts on fishery are commonly evidenced in these cases. The Brazilian Northeast has ponds for which exotic Amazonian species were transferred as Extremoz Lake. These environments serve as study models for comparison and investigation about the possible impacts of these introductions. We tested the hypothesis that loss of species that this trend can be related with the insertion of the genus Cichla, commonly documented as top predator in its endemic environment. Possible structural causes that interfere in other processes such as migration were also investigated. Thus, the local ecological knowledge of fishermen and a current ecotrophic model were used. We took samples of phytoplankton, zooplankton and fishes during two annual cycles. Concurrently, we made interviews with the fishing community. In fact, there are relations between the loss of fish and the insertion of peacock bass in Extremoz Lake. However, Cichla kelberi was not indicated as primary factor to explain fish species decline. The construction of bridges located in the Rio Doce was main factor for respondents and what explains loss of species. The migration of saltwater fish and / or from the river to Extremoz Lake is hindered by the unsuitability of the crossing-streams that are under these structures. According to the ecotrophic model Hoplias malabaricus was considered key-species and Cichla kelberi top predator. This last trend was similarly noticed in the stomach and local ecological knowledge of fishermen analysis. Overfishing simulations to Cichla kelberi resulted that only raising its captures in 200%, other native species would increase their biomass values only 15 to 30% (in 6 years).The negative effects of the alien species introduction without prior studies and lack of investments in appropriating these constructions to the needs of the fish fauna structures seem to act simultaneously. Both are causing the decline of fish species richness and consequent local artisanal fishery collapse

Análise da estrutura genética populacional da piraúna (cephalopholis fulva: serranidae) ao longo da costa e ilhas oceânicas brasileiras

Brazil has about 8,500 km of coastline and on this scale, fishing is a historically important source of animal protein for human consumption. The national fishing background shows a growth of marine fishery production until 1985 and within this period it was recorded a steady decline. From the year 2003 fishing statistics aim to some "recovery" of the total fisheries production, which probably is related to a change in industry practice. The target of commercial fishing became smaller species with low commercial value, but very abundants. The coney, Cephalopholis fulva (Serranidae), is one of these species that have been suffering a greater fishing pressure in recent years. In order to provide data about the current situation of the genetic diversity of these populations, several molecular markers have been being used for this purpose. The prior knowledge of genetic variability is crucial for management and biodiversity conservation. To this end, the control region sequences (dloop) of mtDNA from Cephalopholis fulva (Serranidae) from five geographical points of the coast of Brazil (Ceará, Rio Grande do Norte, Bahia and Espírito Santo) and the Archipelago of Fernando de Noronha (FN) were sequenced and their genetic diversity analyzed. The FST values were very low (0.0246 to 0.000), indicating high gene flow between the sampled spots. The indices h and indicate a secondary contact between previously allopatric lineages differentiated or large and stable populations with long evolutionary history. Tests of Tajima and Fu showed expansion for all populations. In contrast, the mismatch distribution and SSD indicated expansion just for coastal populations. Unlike other species of the Atlantic which have been deeply affected by events on later Pleistocene, the population-genetic patterns of C. fulva may be related to recent events occurred approximately 130,000 years ago. Moreover, the data presented by geographical samples of the specie C. fulva showed high genetic diversity, also indicating the absence of deleterious effects of over-exploitation on this specie, as well as evidence of complete panmixia between all sampled populations

Pobreza e desigualdades socioterritorias: uma problematização acerca da perspectiva territorial nas politicas públicas sociais no município de Pau dos Ferros/RN

El presente trabajo se constituye en un estudio sobre la pobreza y las desigualdades socio territoriales en el Brasil, problematizando la perspectiva territorial de las políticas públicas sociales observando la distribución espacial del Índice de Desarrollo de las familias (IDF) en el municipio de Pau dos Ferros/RN, así como las principales políticas sociales, a ejemplo del Programa Bolsa Familia. En este sentido, el objetivo principal de esa disertación se dió en la tentativa de comprender la importancia de la lectura previa del territorio para la reflexión sobre la pobreza en su aspecto multidimensional y para la territorialización de las políticas Públicas sociales construidas en el intento de minimizar la problemática de la desigualdad social, observando la distribución espacial do IDF en el municipio de Pau dos Ferros/RN. A partir del objetivo general trazado, hicimos una revisión teórica sobre los temas, pobreza, desigualdades sociales y políticas públicas, en el primero caso atentando para el aspecto multidimensional de esta, abogando la importancia de analizarnos la pobreza no apenas por el nivel de rienda, pero considerando otras dimensiones que corroboran para la constitución del ser pobre, como habitaciones precarias, falta de saneamiento básico e infraestructura, el no acceso a la salud, la educación y los otros servicios que posibilitan el individuo vivir con el mejor dignidad. Comprendiendo la importancia del conocimiento previo del territorio para que ocurra las debidas reflexiones e intervenciones en la realidad territorial buscamos reflexionar acerca de ese concepto en sus nexos con la construcción e implementación de las políticas públicas sociales teniendo la Política Nacional de Asistencia Social (PNAS) como política esencial y también el el Programa Bolsa Familia (PBF), una vez que buscamos compreender su importancia a partir de la visión del sujeto, o sea las beneficiadas del PBF en el Municipio de Pau dos Ferros. Para tanto, hicimos entrevistas orales con las beneficiadas del PBF que fueron elegidas aislada a partir de los equipos del CRAS, además de la aplicación de cuestionarios semiesctructurados y abiertos con gestores y asistentes sociales del muninicipio.Buscamos además trabajar con algunos datos del CadÚnico para el município en estudio proponiendo analisar las condiciones sociales y económicas de las famílias cadastradas. Algunos resultados fueron posibles, a saber, es necesario interpretarse la pobreza a partir de varias dimensiones para no tener el riesgo de quedarnos solamente en la perspectiva financiera, o sea de la rienda, que mismo sirva para lo emergencial no es suficiente para transformar las condiciones de vida de las famílias; PNAS puede ser considerada como un avanzo de la política social en el Brasil una vez que posuye importancia fundamental en la familia. Sin embargo, es preciso avanzar en la interpretación del territorio que en la política y en el habla de los agentes sociales , es interpretación apenas como un recorte donde deberán ocurrir las acciones para minimizar la pobreza ; al fin, o PBF es un programa de urgencia moral una vez que combate lo mas emergencial que es el directo de sobrevivir , pero aun no conseguió transformar de una manera significativa la pobreza en el país