906 resultados para neutral segregation of mtDNA
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Introdução. Danos no DNA mitocondrial (DNAmt) têm sido descritos em pacientes com doença renal crônica (DRC). Estes danos podem ser avaliados através da deleção 4977pb do DNAmt em diversos tecidos. Métodos. Identificamos a prevalência da deleção 4977pb do DNAmt através da técnica da reação em cadeia da polimerase (PCR) no sangue de pacientes com DRC em tratamento conservador (creatinina >2mg/dl) ou submetidos a hemodiálise. Resultados. A freqüência da ocorrência da deleção do DNAmt foi de 73.1% (38/52) nos pacientes com DRC submetidos a hemodiálise, 57.1% (27/42) nos pacientes com DRC em tratamento conservador e 27.8% (15/54) nos controles (P< 0.001). Não encontramos aumento da freqüência desta deleção em relação a idade dos pacientes com DRC (P= 0.54) ou ao tempo de diálise (P= 0.70). Conclusão. Danos no DNAmt podem ser induzidos pela DRC em especial nos pacientes submetidos a hemodiálise. Desta forma, a deleção 4977pb do DNAmt pode servir como um marcador de danos moleculares em pacientes com DRC.
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Bali, Cakici e Chabi-Yo (2011) introduziram uma nova medida de risco, englobando as medidas de risco de Aumann e Serrano (2008) e Foster e Hart (2009). Trata-se de um modelo de medida de risco implícito de opções baseado na distribuição neutra ao risco dos retornos de ativos financeiros. Este trabalho se propõe a calcular a medida de risco de Bali, Cakici e Chabi-Yo (2011) com base nas opções de petróleo, a commodity mais importante da economia mundial. Como os preços das opções incorporam a expectativa do mercado, a medida de risco calculada é considerada forward-looking. Desta forma, esse trabalho também analisa a significância dessa medida em prever a atividade econômica futura. Os resultados indicaram poder preditivo em relação ao índice VIX, o qual representa a incerteza do mercado financeiro, e ao índice CFNAI, indicador da atividade econômica norte-americana.
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The general objective of this academic work is to analyze the relationship between the territorial division and the urban expansion process of Mossoró city, understood here as the production and occupation of space. The urban expansion in Mossoró, since its formation as settlement in 1772 until current days, identifies with the Brazilian urbanization process whose growth is determined by the capitalist development. Thus, the expansion was determined by several economical specializations imposed by the territorial division of work which occurs at an interregional level, and, sometimes at an international level. Then, each specialization determined a moment of the urban expansion of the city, as follows: a) The cattle farmer specialization, between 1772 and 1857, when the urban expansion was shy, is summarized to a commercial square that received goods from Aracati aiming to cover a wide rural area; b) The commercial emporium specialization, between 1857 and 1930, when the urban expansion took an important impulse with the concentration of public and private capitals; c) The salt industry and the agricultural-industrial exporter specialization inside a state of development policy, between 1930 and 1970, when the urban expansion, joined to the settlement of the working class in the urban soil, developed along an important axis -the railway; d) The render of services specialization inside a state of intervention policy, between 1970 and 1990, when the urban expansion was characterized by the accelerated growth rhythm, by the reuse of some spaces, and by space segregation of demanding people; e) The render of services policy inside a neoliberal state policy, since 1990 until current days, when the urban expansion reduced its rhythm abruptly, when only small alterations occurred in the existing spaces. It focused on social policies and on several slums eradication programs. Finally, the territorial structure is deeply articulated with others, no territorial, but economical, social and political, which happens at a national, regional and local rate. Only within a historical and conceptual panorama, it was possible to explain the urban expansion in Mossoró from its formation in 1772 until current days. Therefore, this work is a several discipline analysis of the urbanization process existing in Mossoró
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Steam injection is the most used method of additional recovery for the extraction of heavy oil. In this type procedure is common to happen gravitational segregation and this phenomenon can affect the production of oil and therefore, it shoulds be considered in the projects of continuous steam injection. For many years, the gravitational segregation was not adequately considered in the calculation procedures in Reservoir Engineering. The effect of the gravity causes the segregation of fluids inside the porous media according to their densities. The results of simulation arising from reservoirs could provide the ability to deal with the gravity, and it became apparent that the effects of the gravity could significantly affect the performance of the reservoir. It know that the gravitational segregation can happen in almost every case where there is injection of light fluid, specially the steam, and occurs with greater intensity for viscous oil reservoirs. This work discusses the influence of some parameters of the rock-reservoir in segregation as viscosity, permeability, thickness, cover gas, porosity. From a model that shows the phenomenon with greater intensity, optimized some operational parameters as the rate flow rate steam, distance between the wells injector-producer, and interval of completion which contributed to the reduction in gravity override, thus increasing the oil recovery. It was shown a greater technical-economic viability for the model of distance between the wells 100 m. The analysis was performed using the simulator of CMG (Computer Modeling Group-Stars 2007.11, in which was observed by iterating between studied variables in heavy oil reservoirs with similar characteristics to Brazilian Northeast
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The gas injection has become the most important IOR process in the United States. Furthermore, the year 2006 marks the first time the gas injection IOR production has surpassed that of steam injection. In Brazil, the installation of a petrochemical complex in the Northeast of Brazil (Bahia State) offers opportunities for the injection of gases in the fields located in the Recôncavo Basin. Field-scale gas injection applications have almost always been associated with design and operational difficulties. The mobility ratio, which controls the volumetric sweep, between the injected gas and displaced oil bank in gas processes, is typically unfavorable due to the relatively low viscosity of the injected gas. Furthermore, the difference between their densities results in severe gravity segregation of fluids in the reservoirs, consequently leading to poor control in the volumetric sweep. Nowadays, from the above applications of gas injection, the WAG process is most popular. However, in attempting to solve the mobility problems, the WAG process gives rise to other problems associated with increased water saturation in the reservoir including diminished gas injectivity and increased competition to the flow of oil. The low field performance of WAG floods with oil recoveries in the range of 5-10% is a clear indication of these problems. In order to find na effective alternative to WAG, the Gas Assisted Gravity Drainage (GAGD) was developed. This process is designed to take advantage of gravity force to allow vertical segregation between the injected CO2 and reservoir crude oil due to their density difference. This process consists of placing horizontal producers near the bottom of the pay zone and injecting gás through existing vertical wells in field. Homogeneous models were used in this work which can be extrapolated to commercial application for fields located in the Northeast of Brazil. The simulations were performed in a CMG simulator, the STARS 2007.11, where some parameters and their interactions were analyzed. The results have shown that the CO2 injection in GAGD process increased significantly the rate and the final recovery of oil
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In Brazil and around the world, oil companies are looking for, and expected development of new technologies and processes that can increase the oil recovery factor in mature reservoirs, in a simple and inexpensive way. So, the latest research has developed a new process called Gas Assisted Gravity Drainage (GAGD) which was classified as a gas injection IOR. The process, which is undergoing pilot testing in the field, is being extensively studied through physical scale models and core-floods laboratory, due to high oil recoveries in relation to other gas injection IOR. This process consists of injecting gas at the top of a reservoir through horizontal or vertical injector wells and displacing the oil, taking advantage of natural gravity segregation of fluids, to a horizontal producer well placed at the bottom of the reservoir. To study this process it was modeled a homogeneous reservoir and a model of multi-component fluid with characteristics similar to light oil Brazilian fields through a compositional simulator, to optimize the operational parameters. The model of the process was simulated in GEM (CMG, 2009.10). The operational parameters studied were the gas injection rate, the type of gas injection, the location of the injector and production well. We also studied the presence of water drive in the process. The results showed that the maximum vertical spacing between the two wells, caused the maximum recovery of oil in GAGD. Also, it was found that the largest flow injection, it obtained the largest recovery factors. This parameter controls the speed of the front of the gas injected and determined if the gravitational force dominates or not the process in the recovery of oil. Natural gas had better performance than CO2 and that the presence of aquifer in the reservoir was less influential in the process. In economic analysis found that by injecting natural gas is obtained more economically beneficial than CO2
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Os objetivos deste trabalho foram confirmar a herança da resistência da PI 459025 (Rpp4) à ferrugem-asiática-da-soja e identificar marcadores moleculares do tipo RAPD, ligados a este gene de resistência, em populações de soja. Pelo cruzamento dos genitores contrastantes PI 459025 x Coodetec 208 obteve-se uma população, cujas populações das gerações F2 e F2:3 foram artificialmente infectadas e avaliadas quanto à reação ao fungo Phakopsora pachyrhizi, pelo tipo de lesão (RB - resistente e TAN - suscetível). Com os resultados da avaliação fenotípica, dois bulks foram obtidos com DNA de plantas homozigóticas resistentes e suscetíveis, respectivamente, pela análise de bulks segregantes. de 600 iniciadores RAPD aleatórios, foram identificados três com fragmentos polimórficos entre os bulks e parentais contrastantes quanto à resistência. Pela análise do qui-quadrado, confirmaram-se: a herança monogênica, com dominância completa quanto à resistência ao patógeno, e a segregação 3:1 para a presença de banda dos três marcadores. Os três marcadores são ligados respectivamente a 5,1, 6,3 e 14,7 cM de distância do loco de resistência, em fase de repulsão no grupo de ligação G, o que foi confirmado pela utilização do marcador microssatélite Satt288. Estes marcadores são promissores na seleção assistida para resistência à ferrugem-asiática-da-soja.
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The fauna of Brazilian reef fishes comprises approximately 320 species distributed along the coast of the mainland and islands ocean. Little is known about the levels of connectivity between their populations, but has been given the interest in the relations between the offshore and the islands of the Brazil, in a biogeographical perspective. The oceanic islands Brazilian hosting a considerable number of endemic species, which are locally abundant, and divide a substantial portion of its reef fish fauna with the Western Atlantic. Among the richest families of reef fish in species are Pomacentridae. This study analyzed through analysis of sequences of the mitochondrial DNA control region (D-loop), the standards-breeding population of C. Multilineata in different areas of the NE coast of Brazil, involving both oceanic islands (Fernando de Noronha Archipelago and of St. Peter and St. Paul) and continental shelf (RN and BA). To this aim, partial sequences were used in the region HVR1 of mtDNA (312pb). The population structure and parameters for the estimates of genetic variability, molecular variance (AMOVA), estimation of the index for fixing (FST) and number of migrants were determined. The phylogenetic relationships between the populations were estimated using neighbor-joining (NJ) method. A group of Bayesian analysis was used to verify population structure, according to haplotype frequency of each individual. The genetic variability of populations was extremely high. The populations sampled show moderate genetic structure, with a higher degree of genetic divergence being observed for the sample of the Archipelago of St. Peter and St. Paul. At smaller geographical scale, the sample of Rio Grande do Norte and the Archipelago of Fernando de Noronha do not have genetic differentiation. Three moderately differentiated population groups were identified: a population group (I), formed by the Rio Grande do Norte (I') and the archipelago of Fernando de Noronha (I''), and two other different groups formed by the island population of the archipelago of Saint Peter and St. Paul (II) and Bahia (III). The genetic patterns found suggest that the species has suffered a relatively recent radiation favoring the absence of shared haplotypes. C. multilineata seems to constitute a relatively homogenous population along the West Atlantic coast, with evidence of a moderate population genetic structure in relation to the Archipelago of St. Peter and St. Paul. These data supports the importance of the dispersal larvae by marine current and the interpopulation similarity this species.
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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
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This paper aims at analyzing the dynamics of informal housing in Mãe Luiza, in the context of real estate valuation of the city of Natal/RN, which, like any other urban center, has problems related to access to urban land, which increasingly more is appreciated due to their scarcity and, consequently, has led to the segregation of urban spaces. Recently, the informal housing market has received special attention by scholars who wish to discuss the production of space and ways of access to urban land and housing, especially for those disadvantaged by the housing policies of the government where these exist. When talking about the housing market, we are automatically referring to concepts or categories intrinsic to the existing mode of production in our society - the capitalism. Thus, the categories: income, value (use and exchange), commodity, capital, profits and capital gains, along with other important concepts as well as land use (urban) and real estate agents are of great relevance to discussion we intend to do within the context of production space
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The speed and fluidity are basic requirements for reproduction of big capitalism. Thus, the objects and their actions seek to meet these aspirations of hegemony. And among these objects, there is emphasis on the road systems of movement, made up of bridges, viaducts and tunnels, engineering works that cater to this nee increasingly evident in the current period technical-scientific-informational. So on this premise, it becomes apparent that these objects reflect the technical So on this premise, it becomes apparent that these objects reflect the technical space constitution of Natal, capital of Rio Grande do Norte, where the road systems of movement help to understand the process of fragmentation and and spatial segregation of Natal, accelerated in the late twentieth century. Using the analysis as a tool for urban legislation developed in the capital of RN by the municipal administration, this paper seeks to understand, through a matrix of periodization, as these systems move natalense shaped space and which exists for the hegemonic logic limit the formation and location of each of these systems move road, particularly as it concerns the relationship between these and the expansion of opportunities for certain fluidity between the road systems of movement (fixed), their flow
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Comparing introduced to ancestral populations within a phylogeographical context is crucial in any study aiming to understand the ecological genetics of an invasive species. Zaprionus indianus is a cosmopolitan drosophilid that has recently succeeded to expand its geographical range upon three continents (Africa, Asia and the Americas). We studied the distribution of mitochondrial DNA (mtDNA) haplotypes for two genes (CO-I and CO-II) among 23 geographical populations. mtDNA revealed the presence of two well-supported phylogenetic lineages (phylads), with bootstrap value of 100%. Phylad I included three African populations, reinforcing the African-origin hypothesis of the species. Within phylad II, a distinct phylogeographical pattern was discovered: Atlantic populations (from the Americas and Madeira) were closer to the ancestral African populations than to Eastern ones (from Madagascar, Middle East and India). This means that during its passage from endemism to cosmopolitanism, Z. indianus exhibited two independent radiations, the older (the Eastern) to the East, and the younger (the Atlantic) to the West. Discriminant function analysis using 13 morphometrical characters was also able to discriminate between the two molecular phylads (93.34 +/- 1.67%), although detailed morphological analysis of male genitalia using scanning electron microscopy showed no significant differences. Finally, crossing experiments revealed the presence of reproductive barrier between populations from the two phylads, and further between populations within phylad I. Hence, a bona species status was assigned to two new, cryptic species: Zaprionus africanus and Zaprionus gabonicus, and both were encompassed along with Z. indianus and Zaprionus megalorchis into the indianus complex. The ecology of these two species reveals that they are forest dwellers, which explains their restricted endemic distribution, in contrast to their relative cosmopolitan Z. indianus, known to be a human-commensal. Our results reconfirm the great utility of mtDNA at both inter- and intraspecific analyses within the frame of an integrated taxonomical project.
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Pós de titanato zirconato de chumbo (PZT) puros e dopados com bário foram obtidos pelo método de precursores poliméricos, conformados uniaxialmente, na forma de cilindros, utilizando 15 MPa, e prensados isostaticamente à 210MPa. Com o objetivo de estudar o comportamento de sinterização os compactos foram divididos em dois lotes. Sendo um sinterizado em um forno acoplado a um dilatômetro até a temperatura de 1300 °C e o outro sinterizado em forno tipo mufla, em sistema fechado, na temperatura de 1100 °C por 4 horas. Verificou-se que a adição do íon bário influencia na cinética de sinterização, na densificação final, na microestrutura e nas propriedades elétricas da cerâmica. A adição de bário aumenta a concentração da fase tetragonal no PZT, em função da substituição do chumbo por bário na rede perovskita. As amostras dopadas com concentrações maiores que 5,0 mol % em bário apresentaram segregação de PbO no contorno de grão, inibindo seu crescimento.