Características limnológicas e estrutura trófica das comunidades de peixes de alguns lagos naturais e artificiais do Rio Grande do Norte

Artificial lakes must differ from natural lakes in important structural and functional aspects that need to be understood so that these ecosystems can be properly managed. The aim of this work was to test the hypothesis that the artificial lakes (impoundments) in the semi-arid region of the Rio Grande do Norte State are more eutrophic and turbid and have different trophic structure when compared to the natural coastal lakes that occur in the humid eastern coast of the State. To test this hypothesis, 10 natural lakes and 8 artificial lakes with about 100 ha were sampled between September and November 2005 for the determination of some limnological variables and the abundance of the main fish species, which were grouped in three trophic guilds: facultative piscivores, facultative planktivores and omnivores. The results show that the artificial lakes had significantly higher concentrations of total nitrogen, total phosphorus, chlorophyll a , total and volatile suspended solids than the natural lakes. Results also show that the values of pH, total alkalinity, electric conductivity, turbidity as well as the coefficient of vertical attenuation of light were significantly higher in the artificial lakes than in the natural lakes. In the artificial lakes, the abundance of facultative planktivores was significantly higher, while the abundance of facultative piscivores significantly lower than in the natural lakes. There was no significant difference in the abundance of omnivorous fish between the two types of lakes. These results suggest that the increase in turbidity together with the other changes in the water quality of the artificial lakes, modifies the trophic structure of the fish communities reducing the importance of piscivores and the length of the food chains

Memórias de rios e de lagos na construção romanesca: leitura de narrativas da Amazônia paraense

This study focalizes the memoirs of rivers and of lakes in the romantic construction starting from the romances Chove nos campos de Cachoeira (1941), Marajó (1947) and Três casas e um rio (1958), of writer Dalcídio Jurandir; of the book of memoirs Marajó, minha vida (1998), of writer Dita Acatauassu; of the story "A Feiticeira", published in the book Contos Amazônicos, written by Inglês de Sousa (1883); of the short story "O Peixe", published in O carro dos milagres, (1990), of writer Benedicto Monteiro; of the oral narratives Honorato: Cobra Grande , O encanto de Honorato and A Lenda da Cobra Norato , picked up by the project named The Imaginary in the Shape of Oral Narratives of Paraense Amazon (IFNOPAP) of the Federal University of Pará. In those speeches, the voices of the memory detach the multiple functions of rivers and lakes represented as space, atmosphere, scenery, route and route, thread and fabric, re-elaborated in the narrators' memoirs, characters and narrators/character of the fiction and in popular narratives

Veredas infinitas, Recepção italiana de Grandes sertões: veredas

L'obiettivo principale di questo lavoro è valutare le difficoltà di comprensione e di identificazione nella ricezione da parte della cultura italiana dell'opera Grande sertão: veredas, da quelle trovate, in modo pionieristico, dal traduttore italiano, a quelle che sono state percepite e indicate al momento della lettura dai critici, dagli accademici, dall'autore di questo lavoro e, soprattutto, dai lettori comuni, mostrando, allo stesso tempo, che i problemi avuti dagli italiani nella traduzione esistono, sotto certi aspetti, anche per i brasiliani urbani, poiché la dimensione linguistico-geografica presente nel romanzo è così peculiare, che perfino molti lettori di lingua portoghese ignorano il mondo plasmato dal linguaggio di Guimarães Rosa rivelando una esacerbazione della questione universale espressa nella formula "traduttori, traditori". Partendo da tutto ciò, abbiamo cercato di dimostrare che, sebbene la traduzione di Edoardo Bizzarri abbia raggiunto un eccellente risultato, l'opera rosiana, così come nella poesia e di più di qualsiasi altra narrativa, comporta, nel passaggio da un idioma all'altro, perdite irrimediabili, tanto relative all'armonia musicale e ritmica, quanto alla richezza semantica che si occulta nel testo originale

Estudo sistemático de estrelas variáveis na era dos grandes surveys

The interest in the systematic analysis of astronomical time series data, as well as development in astronomical instrumentation and automation over the past two decades has given rise to several questions of how to analyze and synthesize the growing amount of data. These data have led to many discoveries in the areas of modern astronomy asteroseismology, exoplanets and stellar evolution. However, treatment methods and data analysis have failed to follow the development of the instruments themselves, although much effort has been done. In present thesis, we propose new methods of data analysis and two catalogs of the variable stars that allowed the study of rotational modulation and stellar variability. Were analyzed the photometric databases fromtwo distinctmissions: CoRoT (Convection Rotation and planetary Transits) and WFCAM (Wide Field Camera). Furthermore the present work describes several methods for the analysis of photometric data besides propose and refine selection techniques of data using indices of variability. Preliminary results show that variability indices have an efficiency greater than the indices most often used in the literature. An efficient selection of variable stars is essential to improve the efficiency of all subsequent steps. Fromthese analyses were obtained two catalogs; first, fromtheWFCAMdatabase we achieve a catalog with 319 variable stars observed in the photometric bands Y ZJHK. These stars show periods ranging between ∼ 0, 2 to ∼ 560 days whose the variability signatures present RR-Lyrae, Cepheids , LPVs, cataclysmic variables, among many others. Second, from the CoRoT database we selected 4, 206 stars with typical signatures of rotationalmodulation, using a supervised process. These stars show periods ranging between ∼ 0, 33 to ∼ 92 days, amplitude variability between ∼ 0, 001 to ∼ 0, 5 mag, color index (J - H) between ∼ 0, 0 to ∼ 1, 4 mag and spectral type CoRoT FGKM. The WFCAM variable stars catalog is being used to compose a database of light curves to be used as template in an automatic classifier for variable stars observed by the project VVV (Visible and Infrared Survey Telescope for Astronomy) moreover it are a fundamental start point to study different scientific cases. For example, a set of 12 young stars who are in a star formation region and the study of RR Lyrae-whose properties are not well established in the infrared. Based on CoRoT results we were able to show, for the first time, the rotational modulation evolution for an wide homogeneous sample of field stars. The results are inagreement with those expected by the stellar evolution theory. Furthermore, we identified 4 solar-type stars ( with color indices, spectral type, luminosity class and rotation period close to the Sun) besides 400 M-giant stars that we have a special interest to forthcoming studies. From the solar-type stars we can describe the future and past of the Sun while properties of M-stars are not well known. Our results allow concluded that there is a high dependence of the color-period diagram with the reddening in which increase the uncertainties of the age-period realized by previous works using CoRoT data. This thesis provides a large data-set for different scientific works, such as; magnetic activity, cataclysmic variables, brown dwarfs, RR-Lyrae, solar analogous, giant stars, among others. For instance, these data will allow us to study the relationship of magnetic activitywith stellar evolution. Besides these aspects, this thesis presents an improved classification for a significant number of stars in the CoRoT database and introduces a new set of tools that can be used to improve the entire process of the photometric databases analysis

Cidades pequenas, grandes problemas :perfil urbano do Agreste Potiguar

In view of the diversity and the heterogeneity of the existing cities in Brazil, our approach refers to the urban and non-metropolitan areas. Aiming to foment the studies on small cities e to apprehend the sociospatial configuration of the urban environment in such cities, this piece of work elaborates and analyzes the urban profile of the small cities of the Agreste Potiguar region, using as a theoretical reference landmark the production of the urban and regional space, from the decade of 1970 to 2000. Starting from this reference, this piece of work presents an urban sociospatial characterization of the small cities of the Agreste Potiguar region, with emphasis on the economic framework, on the population dynamics, on the main social data, culminating in the main characteristics of the local daily life. The study of the small cities of the Agreste Potiguar region makes it possible the comprehension of the problems that involve the cities of this size, above all, those inserted in economically fragile regions. In the analyzed period, the changes occurred in the productive structure of the State of Rio Grande do Norte triggered a great crisis in the economy of the Agreste Potiguar region. This aspect, allied to the insufficient performance of the public power, contributed to the sprouting of some sociospatial problems, amongst which may be distinguished: the economic fragility, the generalized unemployment, the lack of security and the urban infrastructure absence sufficient to take care of the social demand. Even facing the existing problems, the small cities must be seen as potential spaces, capable to promote the regional development. To do so, it is necessary a process of democratization of the public administration, an ample popular participation and the establishment of a new urban policy, that aims at the social promotion of the individuals, the guarantee of basic necessities and the access to the necessary services to a dignified life

Para compreender a fluidez: os grandes sistemas de movimento viário em Natal/RN

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