Biofunctionalization of titanium surfaces for dental implants: osteogenic, anti-microbial and tribocorrosion resistant surfaces

PhD thesis in Biomedical Engineering

Changes in population and land use over time in the Ecuadorian Amazon

This paper draws upon a detailed longitudinal survey of households living on agricultural plots in the northern three provinces of the Ecuadorian Amazon, the principal region of colonization by migrants in Ecuador since the 1970s. Following the discovery of petroleum in 1967 near what has subsequently come to be the provincial capital and largest Amazonian city of Lago Agrio, oil companies built roads to lay pipelines to extract and pump oil across the Andes for export. As a result, for the past 30 years over half of both Ecuador's export earnings and government revenues have come from petroleum extracted from this region. But the roads also facilitated massive spontaneous in-migration of families from origin areas in the Ecuadorian Sierra, characterized by minifundia and rural poverty. This paper is about those migrants and their effects on the Amazonian landscape. We discuss the data collection methodology and summarize key results on settler characteristics and changes in population, land use, land ownership, technology, labor allocation, and living conditions, as well as the relationships between changes in population and changes in land use over time. The population in the study region has been growing rapidly due to both natural population growth (high fertility) and in-migration. This has led to a dramatic process of subdivision and fragmentation of plots in the 1990's, which contrasts with the consolidation of plots that has occurred in most of the mature frontier areas of the Brazilian Amazon. This fragmentation has led to important changes in land tenure and land use, deforestation, cattle raising, labor allocation, and settler welfare.

Da 'portugalidade' à lusofonia

Tese de Doutoramento em Ciências da Comunicação (Especialidade em Teoria da Cultura)

'Como seiva viva em tronco forte'. A agência noticiosa Lusitânia e o projeto imperial do Estado Novo

O presente estudo pretende descrever as condições políticas e sociais em que foi criada e se desenvolveu a Lusitânia, uma agência noticiosa portuguesa, destinada a contribuir para o fortalecimento do Império português através da difusão do noticiário colonial na metrópole e deste nas colónias. Apesar da escassez de estudos existentes e de não ser conhecido o paradeiro dos arquivos da agência, é possível ainda, através de fontes indiretas, avaliar da importância e do papel ideológico desta agência na construção de um Portugal uno do Minho a Timor, como pretendiam o regime e o fundador da agência, Luís Lupi.

Structural and successional variability of periphytic algal community in a Amazonian lake during the dry and rainy season (Rio Branco, Acre)

The colonization process and successional patterns of a periphytic algal community were evaluated in a Amazonian Viveiro Lake (Rio Branco, Acre, Brazil). Sampling was performed over a period of 35 days; at four-day intervals for 20 days, and then at five-day intervals. Water sampling for physical, chemical and biological analyses was done during the dry and rainy season. Glass slides were used as artificial substrates for periphyton colonization. The structural community was evaluated through population density, algae class, diversity indices and descriptive species. Species richness, diversity and evenness increased as succession progressed. While density of Bacillariophyceae, Euglenophyceae and Zygnemaphyceae increased with succession, Cyanobacteria remained dominant. Synechocystis aquatilis, Synechocystis diplococcus and Navicula pseudolanceolata were the main descriptive species in both the dry and rainy season. Cymbela tumida, Frustulia rhomboides, Trachelomonas lacustris and Closterium acicularis was correlated with an increase in hydrologic level during the rainy season. Conversely, the density of Chlamydomonas sp., Chroomonas nordstedtii, Trachelomonas volvocinopsis, Trachelomonas volvocina and Synechococcus linearis was correlated with an increase in water transparency during the dry season. In general, the periphytic algal community showed high diversity and species richness independent of season. Season also had little influence on representation of algae class and main descriptive species. However, successional patterns varied by season, and changes in hydrologic levels acted directly on the succession path of periphytic algae. More research on periphyton dynamics is needed to improve our understanding of tropical lake ecosystems, especially in Amazonian.

Spatial and temporal evolution of family-farming land use in the Tapajós region of the Brazilian Amazon

Pressures on the Brazilian Amazon forest have been accentuated by agricultural activities practiced by families encouraged to settle in this region in the 1970s by the colonization program of the government. The aims of this study were to analyze the temporal and spatial evolution of land cover and land use (LCLU) in the lower Tapajós region, in the state of Pará. We contrast 11 watersheds that are generally representative of the colonization dynamics in the region. For this purpose, Landsat satellite images from three different years, 1986, 2001, and 2009, were analyzed with Geographic Information Systems. Individual images were subject to an unsupervised classification using the Maximum Likelihood Classification algorithm available on GRASS. The classes retained for the representation of LCLU in this study were: (1) slightly altered old-growth forest, (2) succession forest, (3) crop land and pasture, and (4) bare soil. The analysis and observation of general trends in eleven watersheds shows that LCLU is changing very rapidly. The average deforestation of old-growth forest in all the watersheds was estimated at more than 30% for the period of 1986 to 2009. The local-scale analysis of watersheds reveals the complexity of LCLU, notably in relation to large changes in the temporal and spatial evolution of watersheds. Proximity to the sprawling city of Itaituba is related to the highest rate of deforestation in two watersheds. The opening of roads such as the Transamazonian highway is associated to the second highest rate of deforestation in three watersheds.

Effect of pH on Candida tropicalis virulence factors

Dissertação de mestrado em Bioengenharia

Influence of oxygen conditions on bacterial interactions within biofilms related with cystic fibrosis

Dissertação de mestrado em Bioengineering

Insights into bacterial colony morphology evolution and diversification during infection development in cystic fibrosis

Tese de Doutoramento em Engenharia Biomédica.

Inducción sistémica de la biosintesis de metabolitos secundarios en plantas aromáticas mediada por rizobacterias. Systemic induction of secondary metablolites biosynthesis in aromatic plants by rhizobacteria.

El uso de microorganismos como inoculantes para incrementar la disponibilidad y toma de nutrientes por parte de los cultivos, es una nueva tecnología que ha dado buenos resultados, observándose un incremento en la emergencia, vigor, mayor desarrollo en la parte aérea y de raíces, registrándose aumentos considerables de los rendimientos en cultivos de interés comercial. Esto es debido a que los microorganismos PGPR (Plant Growth promoting rhizobacteria) sintetizan ciertas sustancias reguladoras del crecimiento como giberelinas, citoquininas y auxinas; las cuales estimulan la densidad y longitud de los pelos radicales, aumentando así la cantidad y longitud de las raíces de los vegetales. Así, se incrementa la capacidad de absorción de agua y nutrientes, haciendo que las plantas sean más vigorosas, productivas y tolerantes a condiciones climáticas adversas, como sequías o heladas. Otro factor benéfico es que ciertos microorganismos solubilizan nutrientes poco móviles en el suelo como el caso del fósforo, segundo nutriente, después del nitrógeno en importancia para el crecimiento de los cultivos. Estos microorganismos también tienen una función muy importante en el control natural de agentes patógenos, a través de la inducción del sistema de defensa en las plantas, aumentando su resistencia a enfermedades, a través de la producción de compuestos bacterianos como antibióticos y sideróforos. Los variados mecanismos mediante los cuales la acción PGPR se lleva a cabo no son plenamente conocidos y, por lo tanto, es necesario determinar con precisión su efecto particular en la biología de la planta beneficiada. Las plantas aromáticas y medicinales inoculadas con microorganismos (rizobacterias) registran un incremento en varios parámetros de crecimiento vegetal (peso fresco parte aérea, peso seco de raíz, número de hojas, etc) y en el rendimiento de aceite esencial (AE). El aumento de la síntesis, y la variación de los porcentajes relativos de los componentes principales de AE en plantas aromáticas, como efecto de la inoculación, podría considerarse como una respuesta defensiva de la planta frente a la colonización de microorganismos dado que varios AE poseen propiedades antimicrobianas. El incremento de estos metabolitos también se ha registrado como respuesta frente a la herbivoría. En el presente proyecto se propone dilucidar la existencia de una relación entre las defensas inducidas por rizobacterias con la producción de metabolitos secundarios en plantas aromaticas y medicinales. The use of microorganisms as inoculants to increase the availability and nutrient uptake by crops, is a new technology that has been successfully applied, with an increase in the emergence, vigor, greater development in the shoot and roots, recording significant increases in yields of crop with commercial interest. This is because microorganisms PGPR (Plant Growth Promoting rhizobacteria) synthesize certain growth regulating substances such as gibberellins, cytokinins and auxins, which stimulate the density and length of root hairs, increasing the number and length of roots. Thus, increase the capacity of absorbing water and nutrients, make the plants more vigorous, productive and tolerant to adverse climatic conditions such as drought or frost.Another beneficial factor is that some microorganisms solubilize nutrients mobile in the soil as the case of phosphorus, second nutrient after nitrogen important for plant growth. These organisms also have an important role in the natural control of pathogens through the induction of the plants defense system, increasing their resistance to disease through the production of compounds such as antibiotics and bacterial siderophores. The various mechanisms by which PGPR action takes place are not fully known and therefore it is necessary to accurately determine its particular effect on the biology of the specific plant benefit. Aromatic and medicinal plants inoculated with microorganisms (rhizobacteria) recorded an increase in several parameters of plant growth (shoot fresh weight, root dry weight, leaf number, etc) and essential oil yield (AE). The increase in the biosynthesis, and changes in the relative percentages of the main components of AE in aromatic plants inoculated with rizobacterias, could be regarded as a plant defense response against microbial colonization, since several AE have antimicrobial properties. The increase of these metabolites have also been recorded as a response to herbivory.

Caracterización, procesamiento e industrialización del grano de quinoa, cultivado en la provincia de Córdoba - Argentina. Characterization, processing and industrialization of quinoa seed harvested in the province of Córdoba - Argentina

La quinoa (Chenopodium quinoa Willd), es un pseudocereal originario de la región Andina. Fue utilizada como alimento básico por los pueblos nativos. La quinoa, la papa y el maíz constituyeron el trinomio base de la alimentación indígena de este continente. La colonización española fue desplazando su cultivo a favor del trigo europeo y otros cereales, quedando reducida a las zonas altas de la región andina. La Quínoa ha adquirido una considerable atención en los últimos tiempos, principalmente por la calidad de sus proteínas y la ausencia de gluten en ella. Su empleo está ampliamente difundido en los países andinos, especialmente Bolivia y Perú, con un notable crecimiento de la superficie sembrada. En nuestro país la explotación de este cultivo se ubica principalmente en las provincias norteñas de Salta y Jujuy. En estos últimos años se ha reivindicado su cultivo y los granos privados de saponinas son considerados como un excelente alimento, reconocido por la OMS, la FAO y la NASA. Además de la calidad de sus lípidos y vitaminas, y al elevado contenido en almidón, la quinoa posee una proteína de excelente calidad nutricional y libre de gluten, lo que hace a este grano especialmente indicado para la alimentación de personas que sufren de la enfermedad celíaca o del síndrome de intestino irritado. El presente proyecto está orientado al aprovechamiento integral del grano de quinoa. Es nuestra intensión aquí, demostrar que dicho grano, cultivado en la provincia de Córdoba, permitirá elaborar productos alimenticios asi como también derivados de su industrialización. Para este objetivo se cuenta con las instalaciones de la Planta Piloto del Instituto de Ciencia y Tecnología de los Alimentos (ICTA), de la UNC, así como de intrumental moderno y acorde, como HPLC, GC, Espectrofotómetro UV-Vis, rotavapores de laboratorio e industrial, cámara fría, balanzas analíticas y de precisión, muflas, estufas, molinos y tamices, así como también, contamos con profesionales, algunos de ellos realizando su tesis doctoral en este tema. En cuanto a los objetivos que se persiguen, se espera obtener productos tales como sopas, papillas, productos para panadería y galletería y salsas. En el plano industrial, se pretende elaborar concentrados proteicos, almidón y saponinas. Como se dijo más arriba, a nivel internacional la quinoa ha comenzado a extender sus fronteras, y es así que hoy el principal productor mundial de este grano, Bolivia, destina un porcentaje importante de su producción a la exportación. La creciente demanda mundial de quinoa a hecho que se constituya en un cultivo estratégico y de alto valor, con precios internacionales que rondan los U$S 1200 la tonelada. Si a esto unimos que la planta presenta una gran resistencia a la sequía, que se adapta bien a terrenos salitrosos, arenosos y pobres, podemos comprender la importancia que adquiere para nuestra provincia, toda vez que en la misma existen zonas geográficas potencialmente aptas para su cultivo. Quinoa (Chenopodium quinoa Willd) is a pseudocereal originating in the Andean region. It was used as a staple food by native peoples. Quinoa, potatoes and corn were the tree most important indigenous staple food to this part of South America. Spanish colonization was marginalized cultivation in favor of European wheat and other grains, displacing it to the highlands of the Andean region. Quinoa has recently gained considerable attention, mainly by its protein quality and lack of gluten. Its use is widespread in the Andean countries, especially Bolivia and Peru, with a notable increase in plantings. In our country, the exploitation of this crop is located mainly in the northern provinces of Salta and Jujuy. In recent years its cultivation has been promoted, and the grains once free of saponins are considered an excellent food, recognized by WHO, FAO and NASA. In addition to its lipid and vitamins, and high starch contain, quinoa protein has an excellent nutritional value and it is free of gluten, making it particularly suitable for this grain to feed people with celiac disease or irritable bowel syndrome. This project aims at an integral development of quinoa grain. It is our intention here to demonstrate that this grain grown in the province of Córdoba, can produce food products resulting from local industrialization. This team has access to the facilities of the Pilot Plant of the Institute of Science and Food Technology (ICTA) of the UNC, and the modern equipments in it, as HPLC, GC, UV-Vis spectrophotometer, laboratory and industrial rotary evaporators, cold storage, analytical and precision balances, flasks, ovens, grinders and screens. Also, we have an important professional staff, some of them doing their thesis on this subject. With regard to the objectives pursued, we expect to obtain products such as soups, baby food, bakery products and biscuits and sauces. At the industrial level, it aims at producing protein concentrates, starch and saponins.

Lang anhaltende Prozesse der retinalen Spreading Depression : Untersuchung des intrinsischen optischen Signals

Excitability, wave, reaction-diffusion, chicken, neuron, glia, potassium, nitric oxide, glycolysis

Substituição do farelo de trigo pelo farelo de sabugo de milho

Two 50 R. I. R. chicken groups were contrasted, both receiving the same basic-ration differing only in the content of wheat bran or corn cobs meal. One ration had 10% of wheat bran and in the other one the 10% of wheat bran has been substituted by 10% of corn cobs meal. It was found on the final weight a significant advantage of 12,8% with wheat bran. However, the development of chikens receiving corn cobs meal was quite normal.

Estudos sôbre a coloração da gema de ôvo de galinhas - IV. Efeito da raça e da quantidade de milho amarelo na ração

This paper deals with experiments on the yolk color of chicken eggs. The results obtained can be summarized as follows: a) no differences were observed when different breeds (S. C. W. Leghorn and Rhode Island Red) were fed whith the same ration: yellow corn grains or green feed. b) 30% of yellow corn grain (orange or yellow) in the ration are sufficient to give satisfactory color to the yolk eggs.

O farelinho de trigo fermentado com Bacta-Mon e excremento de vaca na alimentação de pintos

Bacta-mon, produced by Bacta-mon S. A., São Paulo, Brazil, is recommended as a microbiological, and suggested as a supplement for animal rations. This experiment deals with this product in chicken feeding. Four lots of baby chicken received, during 6 weeks the following treatments: a control ration Rl; a ration R2 containing 10 per cent of wheat standard middlings fermented by Bacta-mon, substituting equal weight of wheat standard middlings of the control ration Rl; two rations R3 and R4, both without meat meal and containing 10 per cent of wheat standard middlings fermented respectively by Bactamon and fresh cow manure, substituting equal weight of wheat standard middlings of the control. The results may be so summarized: (1) On the basis of the weights of the chicks at 6 weeks age, we concluded that there was not any advantage in the addition of the wheat standard middlings fermented by Bacta-mon. (2) The rations R3 and R4 were considered statistically equivalents and lower the control ration Rl. (3) It seems that the main difference observed in these results may be atributed to lack of animal protein. (4) The highest mortality and the lowest consumption of feed by the lots receiving ration R3 and R4, seem to indicate, in addition, that this prejudice was due the lack of animal protein and the unpalatability of these rations.