12 resultados para natural control

em Universidade Federal do Rio Grande do Norte(UFRN)


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Soil contamination by pesticides is an environmental problem that needs to be monitored and avoided. However, the lack of fast, accurate and low cost analytical methods for discovering residual pesticide in complex matrices, such as soil, is a problem still unresolved. This problem needs to be solved before we are able to assess the quality of environmental samples. The intensive use of pesticides has increased since the 60s, because the dependence of their use, causing biological imbalances and promoting resistance and recurrence of high populations of pests and pathogens (upwelling). This has contributed to the appearance of new pests that were previously under natural control. To develop analytical methods that are able to quantify residues pesticide in complex environment. It is still a challenge for many laboratories. The integration of two analytical methods one ecotoxicological and another chemical demonstrates the potential for environmental analysis of methamidophos. The aim of this study was to evaluate an ecotoxicological method as "screening" analytical methamidophos in the soil and perform analytical confirmation in the samples of the concentration of the analyte by chemical method LC-MS/MS In this work we tested two soils: a clayey and sandy, both in contact with the kinetic methamidophos model followed pseudo-second order. The clay soil showed higher absorption of methamidophos and followed the Freundlich model, while the sandy, the Langmuir model. The chemical method was validated LC-MS/MS satisfactory, showing all parameters of linearity, range, precision, accuracy, and sensitivity adequate. In chronic ecotoxicological tests with C. dubia, the NOEC was 4.93 and 3.24 for ng L-1 of methamidophos to elutriate assays of sandy and clay soils, respectively. The method for ecotoxicological levels was more sensitive than LC-MS/MS detection of methamidophos, loamy and sandy soils. However, decreasing the concentration of the standard for analytical methamidophos and adjusting for the validation conditions chemical acquires a limit of quantification (LOQ) in ng L-1, consistent with the provisions of ecotoxicological test. The methods described should be used as an analytical tool for methamidophos in soil, and the ecotoxicological analysis can be used as a "screening" and LC-MS/MS as confirmatory analysis of the analyte molecule, confirming the objectives of this work

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SANTANA, André M.; SOUZA, Anderson A. S.; BRITTO, Ricardo S.; ALSINA, Pablo J.; MEDEIROS, Adelardo A. D. Localization of a mobile robot based on odometry and natural landmarks using extended Kalman Filter. In: INTERNATIONAL CONFERENCE ON INFORMATICS IN CONTROL, AUTOMATION AND ROBOTICS, 5., 2008, Funchal, Portugal. Proceedings... Funchal, Portugal: ICINCO, 2008.

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The so-called "residential tourism" came to intensify the previous occupation of the coastal zones, characterized by traditional beach houses, and brought significant consequences for their spatial configuration, and especially for its scenic value of the landscape. Although there is the intention to regulate the activities of enterprising groups by some legal instruments to control the use and occupation of land, and to contain some negative effects, the actions of government are still inefficient in trying to follow the implications on the landscape from the accelerated growth of the real estate and touristic sectors. Supported in the speech of economic development and income generation, public managers prioritize areas to attract tourists to the detriment of preserving important physical attributes of the natural environment that contribute significantly to the quality of life. The result can be noticed in the use of natural elements as one of the major components in the land valorization, and in the immediate attraction of investors and enterprising. Therefore, the objective of this work is to contribute to the debate on the landscape preservation a little detailed thematic in view of their relevance in the current context - by indicating subsidies to the creation of a methodology for the evaluation and protection of coastal zones that may assist the government in creating new instruments, and better prepare it in control of the occupation of these areas. For such, was followed two ways to analysis: the indirect method and the direct method. The first is grounded in the evaluation of landscape attributes, which is based on the work of Raquel Tardin (2008) and Eduardo Cuesta, Encarnación Algarra and Isabel Pastor (2001). The second, based on the research of Leticia and Carlos Hardt (2010) and on the concepts of phenomenology - expressed by Antonio Christofoletti (1985) and Yi-Fu Tuan (1983) - considers the population perspective on the quality of the natural scenery. Developed through cartographic materials, photographic collections and quantitative tables, this dissertation utilized as a case study the beaches of Barra de Tabatinga and Camurupim, located in the city of Nísia Floresta/RN. Despite already being sighted spaces of advanced stage of landscape degradation in these locations, areas of remarkable scenic value can still be found, what reinforce the urgency in adopting preservationists actions. The absence of laws focused on the management and protection of the landscape singularities associated with the inefficiency of the government to invigilate the land occupation in coastal zones, encourage the excessive action of the real estate-tourism, and consequently make the government the main responsible for the environmental and landscape impacts in these areas - by its omission or by their connivance. Therefore, the legislation permeates this entire process and constitutes itself as the most effective way to guarantee the right to the landscape to present and future generations. Are also pointed some important considerations to build a methodology, especially concerning possibilities of improvements and adaptations of its applicability in each case

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The species psaroniocompsa incrustata (Lutz, 1910) was studied in relation to its abundance in different and seasonal periods, the physico-chemical of the breending ground and the fauna predation added to the immature of the species. The study was developed during eight months, from April to July, 2005 (rainy season) and from October, 2005 to January, 2006 (drought season), in one natural breending ground situated in the Pium river, that is part of the hydrographical basin of the Pirangi river in Rio Grande do Norte. The immature of Simuliidae were collected manually in vegetal substrate. At the same place, it was made one sampling of the associated fauna using Suber collectors and the measurement of the environment variants. It was also made one analysis of the stomach content of possible enemies of the simulídeos, to observe the predation of the associated fauna. It was collected 7.713 samples, all from de species P. Incrustata, it was observed a bigger abundance in the drought season, and the entomologic fauna associated totalizing 20.1314 species, distributed in the kinds: Diptera, Ephemeroptera, Odonata, Trichoptera, e Hemiptera, with a bigger representativity of Dipteros. The analysis of the stomach content of the species from the families Libellulidae and Hydropsychidae showed the presence of the simulídeos in only 4% of the material analysed, therefore it was not confirmed the presence of one efficient biological control of the simulídeos in this breending ground

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The Vitamin E consists of eight chemically homologous forms, designated alpha, beta, gamma and delta tocopherols and tocotrienols. Biologically, the alpha-tocopherol (α-TOH) is the most important. Commercially, are found two types of α-TOH a natural (RRR-alpha-tocopherol) and another synthetic (all-rac-alpha-tocopherol). Both forms are absorbed in the intestine, the liver is a preference in favor of forms 2R, due to transfer protein α-TOH. It has higher affinity to these stereoisomers. Newborns are considered high risk for vitamin E deficiency, mainly premature, these have breast milk as a food source for maintenance of serum α-TOH. Clinical signs such as thrombocytosis, hemolytic anemia, retrolental fibroplasia, intraventricular hemorrhage, bronchopulmonary dysplasia and spinocerebellar degeneration can be found in case of a low intake of α-TOH. Thus, maternal supplementation on postpartum with α-TOH can be an efficient way to increase levels of vitamin E in breast milk and thus the consequently increase the supply of micronutrient for the newborn. However, most studies with vitamin E supplementation have been conducted in animals and little is known about the effect of maternal supplementation in humans, as well as on its efficiency to increase levels of α-TOH in human milk, depending on the shape natural or synthetic. The study included 109 women, divided into three groups: control without supplementation (GC) (n=36), supplemented with natural capsule (GNAT) (n=40) and the synthetic capsule (GSINT) (n=33). Blood samples were collected for determination of maternal nutritional status, and colostrums at initial contact and after 24 hours post-supplementation. Analyses were performed by High Performance Liquid Chromatography. Values of α-TOH in serum below 499.6mg/dL were considered deficient. We used the Kruskal-Wallis test and Tukey test to confirm the increase of alpha-tocopherol in milk and efficiency of administered capsules. Daily consumption of α-TOH was based on daily intake of 500 mL of colostrum by the newborn and compared with the nutritional requirement for children from 0 to 6 months of age, 4 mg / day. The mothers had mean concentration of serum α-TOH in 1016 ± 52, 1236 ± 51 and 1083 ± 61 mg / dL, in CG, GNAT and GSINT respectively. There were no women with deficiiency. The GC did not change the concentrations of α-TOH in colostrum. While women supplemented with natural and synthetic forms increased concentrations of α-TOH colostrum in 57.6% and 39%, respectively. By comparing supplemented groups, it was observed a significant difference (p=0.04), the natural capsule more efficient than the synthetic, approximately 49.6%. Individually, 21.1% of the women provided below 4mg/day of α-TOH, after supplementation for this index declined4.1%. Thus, maternal supplementation postpartum raised the levels of alpha-tocopherol in colostrum, and increased efficiency was observed with the natural form

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In a country of continental dimensions as Brazil, one of the top challenges to its economic growth is the logistic related to energetical demand supply. We live now in the era of environmental protection and, in this new context of priorizations, it passes trough the search for alternative energies for the energetic matrix, due the petroleum elevated costs in the global market (and its finitude), but also due its pollution over the environment. This attempt of substitution needs solutions related to the national reality, into a national long term developing plan and based at a juridical-economic analysis of its realization. This study will look for, also based in an economical analysis, the juridical legitimity of choosing natural gas as the new protagonist of national economic growth (as a substitute of petroleum) and the necessary boost that must be done by law, based on an economic policy focused strictly for that fact, as a modifying agent of this reality. This study, therefore, will always be turned to a constitutional aspect, respecting the principles of economic order and the goal of reducing regional inequalities, which must influence the making off of a developing plan. At the end, it will try to demonstrate the juridical viability of such undertaking, tuned in jus-economical criteria. Another goal is related to the analysis of the natural gas industry, due the regulation of its transport has a major importance for national energetic integration, not only because this activity be characterized as a net industry, still under control of a natural monopoly, but also because the competitive or cooperative profile that should be priorized at the beginning of the economic planning for this activity (such as investment policies and its own rules that will submit private agents)

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Nowadays, where the market competition requires products with better quality and a constant search for cost savings and a better use of raw materials, the research for more efficient control strategies becomes vital. In Natural Gas Processin Units (NGPUs), as in the most chemical processes, the quality control is accomplished through their products composition. However, the chemical composition analysis has a long measurement time, even when performed by instruments such as gas chromatographs. This fact hinders the development of control strategies to provide a better process yield. The natural gas processing is one of the most important activities in the petroleum industry. The main economic product of a NGPU is the liquefied petroleum gas (LPG). The LPG is ideally composed by propane and butane, however, in practice, its composition has some contaminants, such as ethane and pentane. In this work is proposed an inferential system using neural networks to estimate the ethane and pentane mole fractions in LPG and the propane mole fraction in residual gas. The goal is to provide the values of these estimated variables in every minute using a single multilayer neural network, making it possibly to apply inferential control techniques in order to monitor the LPG quality and to reduce the propane loss in the process. To develop this work a NGPU was simulated in HYSYS R software, composed by two distillation collumns: deethanizer and debutanizer. The inference is performed through the process variables of the PID controllers present in the instrumentation of these columns. To reduce the complexity of the inferential neural network is used the statistical technique of principal component analysis to decrease the number of network inputs, thus forming a hybrid inferential system. It is also proposed in this work a simple strategy to correct the inferential system in real-time, based on measurements of the chromatographs which may exist in process under study

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In energy systems, the balance of entrances, exits and losses are fundamental to rationalize the energy consumption, independently of the source (sun, natural gas, wind, water, firewood or oil). This estimate is important so much in the phase of project of the facilities, as in the exploration or operation. In the project phase it indicates the energy needs of the process and the contribution of the energy in the cost of the product and the capacity of storage of the fuel and in the operation phase it allows to evaluate the use of the energy in the process of it burns, showing the weak points that should suffer intervention to improve the efficiency. With this tool, it can be implemented routines of calculation of thermal balances in ovens of it burns of structural ceramic, in way to generate an optimized mathematical model for application in the current and promising structural ceramic brazilian industry. The ceramic oven in study is located in the metropolitan area of Natal (Rio Grande do Norte) and it is a continuous oven of the type wagons tunnel, converted of firewood for natural gas and it produces blocks of red ceramic. The energy balance was applied in the oven tunnel before and after the conversion and made the comparisons of the energy efficiencies (it burns to the firewood and it burns to natural gas), what showed that the gaseous fuel is more efficient when we burn structural ceramic in ovens tunnels. When we burn natural gas, the requested energy is smaller and better used. Tests were accomplished in the burned product that showed the best quality of the burned brick with natural gas. That quality improvement makes possible to accomplish new interventions for the most rational use of the energy in the oven tunnel of the Ceramic in study and in the industries of structural ceramic of the whole Brazil, that need control tools of burning and of quality

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SANTANA, André M.; SOUZA, Anderson A. S.; BRITTO, Ricardo S.; ALSINA, Pablo J.; MEDEIROS, Adelardo A. D. Localization of a mobile robot based on odometry and natural landmarks using extended Kalman Filter. In: INTERNATIONAL CONFERENCE ON INFORMATICS IN CONTROL, AUTOMATION AND ROBOTICS, 5., 2008, Funchal, Portugal. Proceedings... Funchal, Portugal: ICINCO, 2008.

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The so-called "residential tourism" came to intensify the previous occupation of the coastal zones, characterized by traditional beach houses, and brought significant consequences for their spatial configuration, and especially for its scenic value of the landscape. Although there is the intention to regulate the activities of enterprising groups by some legal instruments to control the use and occupation of land, and to contain some negative effects, the actions of government are still inefficient in trying to follow the implications on the landscape from the accelerated growth of the real estate and touristic sectors. Supported in the speech of economic development and income generation, public managers prioritize areas to attract tourists to the detriment of preserving important physical attributes of the natural environment that contribute significantly to the quality of life. The result can be noticed in the use of natural elements as one of the major components in the land valorization, and in the immediate attraction of investors and enterprising. Therefore, the objective of this work is to contribute to the debate on the landscape preservation a little detailed thematic in view of their relevance in the current context - by indicating subsidies to the creation of a methodology for the evaluation and protection of coastal zones that may assist the government in creating new instruments, and better prepare it in control of the occupation of these areas. For such, was followed two ways to analysis: the indirect method and the direct method. The first is grounded in the evaluation of landscape attributes, which is based on the work of Raquel Tardin (2008) and Eduardo Cuesta, Encarnación Algarra and Isabel Pastor (2001). The second, based on the research of Leticia and Carlos Hardt (2010) and on the concepts of phenomenology - expressed by Antonio Christofoletti (1985) and Yi-Fu Tuan (1983) - considers the population perspective on the quality of the natural scenery. Developed through cartographic materials, photographic collections and quantitative tables, this dissertation utilized as a case study the beaches of Barra de Tabatinga and Camurupim, located in the city of Nísia Floresta/RN. Despite already being sighted spaces of advanced stage of landscape degradation in these locations, areas of remarkable scenic value can still be found, what reinforce the urgency in adopting preservationists actions. The absence of laws focused on the management and protection of the landscape singularities associated with the inefficiency of the government to invigilate the land occupation in coastal zones, encourage the excessive action of the real estate-tourism, and consequently make the government the main responsible for the environmental and landscape impacts in these areas - by its omission or by their connivance. Therefore, the legislation permeates this entire process and constitutes itself as the most effective way to guarantee the right to the landscape to present and future generations. Are also pointed some important considerations to build a methodology, especially concerning possibilities of improvements and adaptations of its applicability in each case

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The species psaroniocompsa incrustata (Lutz, 1910) was studied in relation to its abundance in different and seasonal periods, the physico-chemical of the breending ground and the fauna predation added to the immature of the species. The study was developed during eight months, from April to July, 2005 (rainy season) and from October, 2005 to January, 2006 (drought season), in one natural breending ground situated in the Pium river, that is part of the hydrographical basin of the Pirangi river in Rio Grande do Norte. The immature of Simuliidae were collected manually in vegetal substrate. At the same place, it was made one sampling of the associated fauna using Suber collectors and the measurement of the environment variants. It was also made one analysis of the stomach content of possible enemies of the simulídeos, to observe the predation of the associated fauna. It was collected 7.713 samples, all from de species P. Incrustata, it was observed a bigger abundance in the drought season, and the entomologic fauna associated totalizing 20.1314 species, distributed in the kinds: Diptera, Ephemeroptera, Odonata, Trichoptera, e Hemiptera, with a bigger representativity of Dipteros. The analysis of the stomach content of the species from the families Libellulidae and Hydropsychidae showed the presence of the simulídeos in only 4% of the material analysed, therefore it was not confirmed the presence of one efficient biological control of the simulídeos in this breending ground

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The Vitamin E consists of eight chemically homologous forms, designated alpha, beta, gamma and delta tocopherols and tocotrienols. Biologically, the alpha-tocopherol (α-TOH) is the most important. Commercially, are found two types of α-TOH a natural (RRR-alpha-tocopherol) and another synthetic (all-rac-alpha-tocopherol). Both forms are absorbed in the intestine, the liver is a preference in favor of forms 2R, due to transfer protein α-TOH. It has higher affinity to these stereoisomers. Newborns are considered high risk for vitamin E deficiency, mainly premature, these have breast milk as a food source for maintenance of serum α-TOH. Clinical signs such as thrombocytosis, hemolytic anemia, retrolental fibroplasia, intraventricular hemorrhage, bronchopulmonary dysplasia and spinocerebellar degeneration can be found in case of a low intake of α-TOH. Thus, maternal supplementation on postpartum with α-TOH can be an efficient way to increase levels of vitamin E in breast milk and thus the consequently increase the supply of micronutrient for the newborn. However, most studies with vitamin E supplementation have been conducted in animals and little is known about the effect of maternal supplementation in humans, as well as on its efficiency to increase levels of α-TOH in human milk, depending on the shape natural or synthetic. The study included 109 women, divided into three groups: control without supplementation (GC) (n=36), supplemented with natural capsule (GNAT) (n=40) and the synthetic capsule (GSINT) (n=33). Blood samples were collected for determination of maternal nutritional status, and colostrums at initial contact and after 24 hours post-supplementation. Analyses were performed by High Performance Liquid Chromatography. Values of α-TOH in serum below 499.6mg/dL were considered deficient. We used the Kruskal-Wallis test and Tukey test to confirm the increase of alpha-tocopherol in milk and efficiency of administered capsules. Daily consumption of α-TOH was based on daily intake of 500 mL of colostrum by the newborn and compared with the nutritional requirement for children from 0 to 6 months of age, 4 mg / day. The mothers had mean concentration of serum α-TOH in 1016 ± 52, 1236 ± 51 and 1083 ± 61 mg / dL, in CG, GNAT and GSINT respectively. There were no women with deficiiency. The GC did not change the concentrations of α-TOH in colostrum. While women supplemented with natural and synthetic forms increased concentrations of α-TOH colostrum in 57.6% and 39%, respectively. By comparing supplemented groups, it was observed a significant difference (p=0.04), the natural capsule more efficient than the synthetic, approximately 49.6%. Individually, 21.1% of the women provided below 4mg/day of α-TOH, after supplementation for this index declined4.1%. Thus, maternal supplementation postpartum raised the levels of alpha-tocopherol in colostrum, and increased efficiency was observed with the natural form