All-optical processing systems based on semiconductor optical amplifiers

Doutoramento em Engenharia ElectrotécnicaNesta tese investigam-se e desenvolvem-se dispositivos para processamento integralmente óptico em redes com multiplexagem densa por divisão no comprimento de onda (DWDM). O principal objectivo das redes DWDM é transportar e distribuir um espectro óptico densamente multiplexado com sinais de débito binário ultra elevado, ao longo de centenas ou milhares de quilómetros de fibra óptica. Estes sinais devem ser transportados e encaminhados no domínio óptico de forma transparente, sem conversões óptico-eléctrico-ópticas (OEO), evitando as suas limitações e custos. A tecnologia baseada em amplificadores ópticos de semicondutor (SOA) é promissora graças aos seus efeitos não-lineares ultra-rápidos e eficientes, ao potencial para integração, reduzido consumo de potência e custos. Conversores de comprimento de onda são o elemento óptico básico para aumentar a capacidade da rede e evitar o bloqueio de comprimentos de onda. Neste trabalho, são estudados e analisados experimentalmente métodos para aumentar a largura de banda operacional de conversores de modulação cruzada de ganho (XGM), a fim de permitir a operação do SOA para além das suas limitações físicas. Conversão de um comprimento de onda, e conversão simultânea de múltiplos comprimentos de onda são testadas, usando interferómetros de Mach-Zehnder com SOA. As redes DWDM de alto débito binário requerem formatos de modulação optimizados, com elevada tolerância aos efeitos nefastos da fibra, e reduzida ocupação espectral. Para esse efeito, é vital desenvolver conversores integramente ópticos de formatos de modulação, a fim de permitir a interligação entre as redes já instaladas, que operam com modulação de intensidade, e as redes modernas, que utilizam formatos de modulação avançados. No âmbito deste trabalho é proposto um conversor integralmente óptico de formato entre modulação óptica de banda lateral dupla e modulação óptica de banda lateral residual; este é caracterizado através de simulação e experimentalmente. Adicionalmente, é proposto um conversor para formato de portadora suprimida, através de XGM e modulação cruzada de fase. A interligação entre as redes de transporte com débito binário ultra-elevado e as redes de acesso com débito binário reduzido requer conversão óptica de formato de impulso entre retorno-a-zero (RZ) e não-RZ. São aqui propostas e investigadas duas estruturas distintas: uma baseada em filtragem desalinhada do sinal convertido por XGM; uma segunda utiliza as dinâmicas do laser interno de um SOA com ganho limitado (GC-SOA). Regeneração integralmente óptica é essencial para reduzir os custos das redes. Dois esquemas distintos são utilizados para regeneração: uma estrutura baseada em MZI-SOA, e um método no qual o laser interno de um GC-SOA é modulado com o sinal distorcido a regenerar. A maioria dos esquemas referidos é testada experimentalmente a 40 Gb/s, com potencial para aplicação a débitos binários superiores, demonstrado que os SOA são uma tecnologia basilar para as redes ópticas do futuro.This thesis investigates and develops all-optical processing devices for wavelength division multiplexing networks (DWM) of the future. The ultimate goal of optical networks is to transport and deliver a densely multiplexed spectrum, populated by ultra-high bit rate signals over hundreds or thousands of kilometers of optical fiber. Such signals should be transported and routed transparently in the optical domain, without recurring to optic-electro-optic (OEO) conversions, avoiding its limitations and costs. Semiconductor optical amplifier (SOA) based technology is a promising building block due to its inherent ultra-fast and efficient non-linear effects, potential for integration, low power consumption and cost. Wavelength converters are the basic optical functionality to increase the network throughput and avoid wavelength blocking. Methods to increase the operation bandwidth of cross-gain modulation (XGM) converters are studied and experimentally assessed to enable operation beyond the physical constraints of SOA. Single and multi-wavelength conversion exploiting crossphase modulation (XPM) in Mach-Zehnder interferometer with semiconductor optical amplifiers (MZI-SOA) is tested. High bit rate DWDM networks require optimized modulation formats with enhanced tolerance to fiber impairments and reduced spectral tolerance. As a consequence, it is crucial to develop all-optical modulation formats between legacy on-off-keying networks and networks employing advanced modulation formats. An all-optical format converter between optical double sideband (ODSB) and optical vestigial sideband (OVSB) based on SOA self-phase modulation is proposed and thoroughly characterized by simulations and experimental tests. A converter, which uses a mix of XGM and XPM to allow simultaneous pulse and modulation format conversion to the carrier suppressed format, is proposed. The interface between ultra-high bit rate transport networks and lower bit rate access networks requires optical pulse format conversions between return-tozero (RZ) and non-return-to-zero (NRZ). Two different structures are proposed and investigated. The first is based on detuned filtering of XPM converted signal; while the second uses the dynamics of the internal laser of a gainclamped SOA. All-optical regeneration is one of the most sought functionalities to reduce network costs. Regeneration is achieved in this work through two simple setups: a MZI-SOA based structure, and a method in which the internal laser from a GC-SOA is modulated with the input distorted signal. Most applications are experimentally validated at 40 Gb/s, with potential for even higher bit rates, demonstrating that SOA can be one of the key elements for the next generation of optical networks

Synthesis, Characterization and Stabilization Analysis of Ferrofluid Based on Amazon Vegetable Copaifera O. L. Oil

The Nanoscience and Nanobiotechnology develops several researches using nanostructures with magnetic properties. These nanostructures can have different physical properties depending on their composition and therefore can be used in various applications such as: drug markers and carriers, microelectronics, magnetic separations and environmental applications. Furthermore, the use of natural components in the synthesis of these nanostructures may come to complement these nanomaterials due to their underexplored properties and their renewable origin. This research will aim to carry out a pre-study to analyze the stability of magnetic fluids based on Fe3O4 nanoparticles functionalized with vegetable oil from the Copaifera SPP plant, known as Copaiba. Therefore, the Fe3O4 nanoparticles will be synthesized by the coprecipitation method by hydrolysis in an alkaline solution. Ferrofluid will be prepared by dispersing magnetic nanoparticles, at different concentrations, in the “in natura” oil. For the samples characterization measurements were taken of: UV-vis, FTIR, NIR spectrophotometry, XRD and Magnetic Susceptibility, the temporal analysis was recorded periodically, observing the possible stability of the samples. This work reports that the ferrofluid showed good stability and the magnetic properties associated with the nanoparticles the properties of the Amazon oil used

Potencial fisiológico de sementes de leguminosas submetidas à permanência em mistura mineral

Se objetivó con estudio evaluar el potencial fisiológico de semillas de cuatro leguminosas forrajeras tropicales sometidas a la permanencia en mezcla mineral para bovinos, por el test de germinación, por el test de envejecimiento acelerado y por la prueba de conductividad eléctrica, con el propósito de dispersarlas Pastoreo por las heces bovinas. El delineamiento experimental fue completamente casualizado en esquema factorial 4x7 (cuatro especies, siete tratamientos), con cuatro repeticiones. Las semillas permanecieron en la mezcla mineral por: 0, 12, 24, 36, 48, 72 y 96 horas. El estrés salino, hasta 24 horas, no representó riesgo para la germinación de las semillas. Así, la introducción de semillas en mezcla mineral para bovinos para la dispersión de leguminosas en el pastoreo puede ser utilizada.Objective of this study was to evaluate the potential physiologic potential of seeds of four tropical forage legumes submitted to the permanence in mineral mixture for bovine, for the germination test, for the accelerated aging test and for the electric conductivity test, with the intention of dispersing them in the pasture by the bovine feces. A completely randomized design at factorial scheme 4x7 (four species, seven treatments) with four repetitions was used. The seeds stayed in the mineral mixture for: 0, 12, 24, 36, 48, 72 and 96 hours. The saline stress, up to 24 hours, did not represent risk for the germination of the seeds. Like this, the introduction of seeds in mineral mixture for bovines for dispersion of legumes in the pasture can used.Objetivou-se com estudo avaliar o potencial fisiológico de sementes de quatro leguminosas forrageiras tropicais submetidas à permanência em mistura mineral para bovinos, pelo teste de germinação, pelo teste de envelhecimento acelerado e pelo teste de condutividade elétrica, com o intuito de dispersá-las na pastagem pelas fezes bovinas. O delineamento experimental foi inteiramente casualizado em esquema fatorial 4x7 (quatro espécies, sete tratamentos), com quatro repetições. As sementes permaneceram na mistura mineral por: 0, 12, 24, 36, 48, 72 e 96 horas. O estresse salino, até 24 horas, não representou risco para a germinação das sementes. Assim, a introdução de sementes em mistura mineral para bovinos para a dispersão de leguminosas na pastagem pode ser utilizada

Economical Feasibility of Strawberry Production in a Semi-Hydroponic System and Agroindustry of Jelly on a Small Property

Growing strawberries is a great alternative for family farms, it is possible to obtain a good financial return on a small property. Consumption growth Strawberry "in natura" in recent years, along with a high price increase, further assists in the marketing of the fruit. This study aimed to establish a greenhouse to grow plants behave 18,000 Camarosa, with approximate production of 200 kg of strawberries daily in peak harvest in semi-hydroponic system in a family owned, located in the municipality of Canguçu-RS. The strawberry produced should be packaged for sale "in natura" and received in the form of jelly. Strawberries are classified by their diameter (25mm and 15mm) and defects in three classes: Class A, includes all healthy and greater than 25 mm diameter strawberries; class B, includes all the healthy strawberries and with a diameter between 25 mm and 15 mm and the class C, includes all strawberries with less than 15mm diameter. The strawberries in Classes A and B will be sold as "in natura" and Class C will be used for the production of jam. To perform the economic analysis, initially used the SWOT matrix, which is a tool used to perform environmental analysis, as the basis of management and strategic planning. The financial analysis of the project was carried out through the following indications: NPV (Net Present Value), IRR (Internal Rate of Return) and payback. Through the completion of the procedures for determining the cash flow and economic indicators, it was found through studies of scenarios, keeping the price constant and equal to jam £ 5.50, the minimum price of the strawberry "in natura" is worth $ 6.83. The production of jelly is an alternative to adding value to the product and also provides more time for marketing

Produção de matéria seca, composição química e radicular de leguminosas forrageiras tropicais semeadas por fezes bovinas

Objetivou-se avaliar a produção de matéria seca da parte aérea e radicular e composição bromatológica de três leguminosas forrageiras tropicais (Clitorea ternatea, Macrotyloma axillare e Neonotonia wightii) que após terem suas sementes passadas pelo trato digestório de bovinos, germinaram e se desenvolveram em placas fecais bovinas. O delineamento experimental adotado foi inteiramente casualizado, em um esquema fatorial 3 (espécies) x 3 (intervalos de dispersão: entre 12 e 18; entre 18 e 24, entre 24 e 30 h), com quatro repetições. Foram oferecidos 50 g de sementes misturadas a 150 g de suplemento mineral para bovinos (5 animais) por repetição. As fezes bovinas foram coletadas e alocadas em vasos, onde permaneceram por 120 dias. Ao fim deste período, as plantas presentes nas fezes foram contadas e cortadas e foram realizadas analises para determinação da produção de matéria seca da parte aérea e radicular, teor de proteína bruta (PB), fibra em detergente neutro (FDN) e fibra em detergente ácido (FDA). As plantas desenvolvidas nas fezes foram capazes de produzir 2,54 g de MS por planta. A espécie soja perene apresentou a maior produção de matéria seca da parte aérea (2,81 g/planta) e radicular (2,05 g/planta). Os teores de PB, FDN e FDA não sofreram alterações dentro dos períodos de dispersão em que as sementes foram cultivadas

Occurrence of Intestinal Parasites in Alouatta caraya of the Zoobotanical Park of Teresina, Piauí, Brazil

Background: The animals of the genus Alouatta are popularly known as Bugios, barbados, roncadores and guaribas, being the neotropical primates better studied in the world. They originate in South America, with records in Argentina, Bolivia, Paraguay and Uruguay. Because of their migrations, many are found debilitated and taken to captivity until their rehabilitation and most cannot be reinserted in nature. They tend to live in extensive areas, having a low resistance against parasitic infections because of low exposure and when kept in captivity, the risks of these infections increase. Some diagnostic techniques can aid in the detection of parasites of zoo animals and can identify the parasitic fauna of these animals. The objective of this work was to investigate and report the presence of intestinal parasites in a female Bugio-preta (Alouatta caraya) captive of the Zoobotanical Park of the municipality of Teresina, Piauí, Brazil.Case: The animal presented a constipation signs before clinical signs of apathy, anorexia, diarrhea and weight loss, suggestive signs of parasitosis, Sterile papers were placed on the floor of the animal enclosure and collected fresh stools shortly after defecation, the feces were removed using gloves, stored in a capped containers, identified and taken to the Laboratory of Parasitology of the Department of Parasitology and Microbiology of the Federal University of Piauí, for further evaluation. The fecal samples were submitted to the techniques of spontaneous sedimentation (HPJ), centrifugation-flotation (Faust) and flotation method in hyper saturated sucrose solution (Willis-Mollay), obtaining slides that were analyzed under an optical microscope in the 10x and 40x objective, confirming the presence of ascarids and hookworms.Discussion: The results showed the presence of eggs of Ascaris sp. and Ancylostoma sp. in all of the analyzed techniques, thus maintaining an alert, since they are considered helminths of zoonotic character. The general state of the animal may have influenced considerably the result of mixed infection by helminths, since it had episodes of diarrhea and was skinny at the time of diagnosis. Diarrheal feces and slimming favor the encounter of mixed infection, since the parasites in large quantity can cause to their hosts a decrease in the absorption of nutrients and an intestinal peristalsis increase. Other works with primates also revealed the presence of parasites in animals, including protozoans. The collection moment and evaluation of the fecal samples of the Bugio coincided with the rainy period in the region. This fact can favor the increase of eggs and larvae of parasites in the environment and, consequently, can contaminate the animals. Regarding to sanitary management of zoos, areas full of plants and trees make it difficult to hygienize the enclosures and in these places is common the presence of other animals that can serve as carriers of pathogens. The available diagnostic great relevance to assess the degree of animal infection, the possibility of transmission and the sanitary conditions of the environment. It was concluded that the female Bugio of the Teresina Zoobotanical Park was parasitized by ascarids and hookworms and the techniques of parasitological exams performed represented great relevance for the early diagnosis and an appropriate treatment, being able to be used for the control of diseases parasites, mainly zoonoses

Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli

Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts.  Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins.  Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets