Modelo de avaliação de risco : São o crescimento e a estequiometria dos girinos afetados pelo efeito interativo entre a presença do predador e da densidade de coespecíficos?

Many prey organisms change their phenotype to reduce the predation risk. However, such changes are associated with trade-offs, and can have negative effects on prey growth or reproduction. Understand how preys assess the predation risk is essential to evaluate the adaptive value of predator-induced phenotypic and its ecological consequences. In this study, we performed a mesocosm experiment to test: i) if growth and stoichiometry of Lithobates catesbeianus tadpoles is altered in response to giant water bug presence (Belostoma spp.); ii) if these responses depend on tadpoles density in environment. Here, we show that tadpoles growth and stoichiometry are not changed by predator presence, neither in low nor in high densities. Our results suggest that tadpoles exposed to predation risk regulate their physiology to preserve the elemental stoichiometric homeostase of their body and excretion. Further, point out to need for future studies that elucidate under what conditions growth and stoichiometry are changed in response to predation risk

Nas asas de Ícaro: uma análise da Pedagogia Freinet do 2º ao 5º ano do Ensino Fundamental na perspectiva da ação docente continuada

Célestin Freinet was one of the most memorable educators of the twentieth century. He presented some educational alternatives that had the objective of stimulating the construction of pedagogic actions to promote the social development of the student based upon a work centered on the free expression as the way to self-structure the knowledge. With a permanent proposal of research based on the enquiry-based learning, Freinet set human capacity (cognitive, social-affective, psychometrical) taking cooperation in consideration on the processes of knowledge construction. Based on this referential, this present work has the objective to show Freinet s pedagogy in a continuous teaching action from 2nd to 5th grade focusing the teacher s discourse and also the educative practice of the students of a city public school in Natal. The observed work revealed the teacher s discourse and educative experience and delineated the students development while immersed into Freinet s educational practice. By virtue of the nature and specificity of the theme that guided our research, we chose a qualitative approach to it, as a way of conducting ourselves during our investigative process. We observed and analyzed the method that was used to conduct the activities in the classroom, as well as the ways of expression that the children used through drawings, words (oral text), or through writing. We highlight, among the written texts, the individual and collective texts, and also letters and notes, which during some moments served as a base to express a diversity of languages. The results, after a analyzing the research data, point towards a teaching practice that favors the construction of a significant learning process through the grasping of the school environment, on which all these factors are based: society, knowledge acquisition, abilities, attitudes and values. This learning process also strengthens human solidarity bonds and mutual tolerance, on which the student s social life is seated.

A encruzilhada da vida política em assentamentos de reforma agrária no Rio Grande do Norte

The rural settlements represent a mark in the expensive historical process of fight by the land in Brazil. At first offer basic terms of survival, through the access the land and of the fundamental supports for exploration. At the same time, have stimulated organization forms politicizes of the families who manage to work with the new challenges of the everyday. The moment that follows the land conquest, and therefore, the settlements construction while life and work project, it is crossed for objective and subjective demands, with highlight for options of agricultural production and strategies of collective action. Originally formed as representation instance legitimates of the families - front to the government and social actors - the settlers associations are private spaces for political sociability, that guided by principles participative, can lead the settlers the new conquests through indeed democratic experiences. The goal of this work is to comprehend the participation forms in the scope of these associations and the way as that translates in life best terms for the group, from the settlements experiences located in the Territories of the Citizenship Mato Grande and Açu-Mossoró, in Rio Grande do Norte's State. The theoretical conceptions that guide this analysis are concentrate on discussions about democracy and participation (Patermam, Putnam, Bodernave) and in the reflections about the rural world (Medeiros, Martins, Woodman e Woodman and Bergamansco). About methodological, different point of view strategies were developed: The direct observation, the application in locate of questionnaires to the families settlers and interviews semi-structured with the internal leaderships. With that could verify that the participation forms in the associations operate in two heartfelt: Of a side, they promote assimilation opportunities of democratic abilities accompanied of notions of social rights and redefinition of political standards; Of another, it offers indeed the possibility of the settlers lead, with relative autonomy, the political organization and her changes in direction to a way of life that wish to have in the settling

Eça de Queiroz e a cozinha burguesa: literatura e alimentação

Using literature to discuss the topic of food, proper bourgeois cuisine, was the purpose of this work. As a corpus, we use one of the works of Eça de Queiroz, The City and the Mountains. Served as theoretical references the Claude Levi-Strauss s concept of universal culinary and the Jean Claude Fischler s concept of specific culinary who understands food as a cultural system which includes representations, beliefs and practices of a specific group. After the initial reading of the novel and construction of a file containing general information of the work, categories designed for elaboration of a material for analysis were these: work, characters, food, intellectuals and geographies. We realized the culinary as an epicenter for understanding the culture of a specific group: in this case, the bourgeois. We proposed a quaternary model for systematizing it: this bourgeois cuisine highlights the technique, has affection for what is rare and/or expensive but still consume it with temperance, establishing a new relationship with the use of time and, finally, it is the one that opens the ritual that involves frequent restaurants and cafes. The exercise of thinking the bourgeois cuisine through the literature suggests that the art may work on increase the comprehensive capabilities of nutritionists, professionals who deal with a complex object in your practice: the food

Ciência como montagem, montagem como ciência

The thesis describes parallel possibilities between the knowledge built in theatre and in Science. The narrative is constructed through a reflexive observation of the process of making a threatical play, specifically O Tempo da Chuva by Grupo Beira de Teatro , in analogy to the process of making a scientific theory, specifically the one described by Werner Heisenberg in his book Physics and Beyond: encounters and conversations . It sets a dialog with authors/actors from various areas of knowledge, such as Edgar Morin, Werner Heisenberg, René Descartes, Paul Feyerabend, Paul Caro, Juremir Machado da Silva, Maria da Conceição de Almeida, Renato Ferracini, among others. It discusses the hypothesis that Science is the process of building and the theatrical process of building a play can also be systematized, likewise science. The thesis defends, as the complexities science may suggest, a method as a strategy. Developed throughout the process, such method could only be verified at the end, when the elements of the setting of atomic physics theories and theatre were correlated. Questions such as: the place of theatre and science in our contemporary society and the political and ethical role of artists and scientists are at the episthemological basis of this narrative which we have started, but it is not even close to a conclusion

Respostas funcionais de diferentes tamanhos de Tilápia do Nilo; Oreochromis niloticus; predando zooplâncton

The Nile tilapia, Oreochromis niloticus, is an important omnivorous fish in the reservoirs of the semi-arid region of Brazil. Throughout its growth tilapia s feeding behavior changes from a visual predator of zooplankton to a filter-feeder, collecting suspended particulate matter, including planktonic organisms, through pumping. This feature results in different impacts of tilapia on plankton community as the fish grows. Aiming to quantify the functional response of different sizes of Nile tilapia on zooplankton experiments in microcosms scale in the laboratory and in mesocosm scale in the field were carried out. The data were fitted to four different models of functional response. The best fits were obtained for nonlinear models in laboratory experiments. While the experiments in mesocosms were the best settings for responses of type I (juvenile and adult tilapia) and type III (fry). The Manly's alpha index was used to evaluate the feeding selectivity of tilapia on the three main groups of the zooplankton in the experiments in mesocosms. The results show that: (i) rotifers were the preferred prey of fingerlings,(ii) copepods were rejected by fry and juvenile tilapia and (iii) adult fish fed non-selectively on copepods, cladocerans and rotifers. The functional response models obtained in this research can be applied to population models and help in modeling the dynamics of interactions between Nile tilapia and the planktonic communities in the reservoirs of the semi-arid

Relações ecologicas entre caranguejos e composição arbórea em bosques de mangue naturais e restaurados no nordeste brasileiro

This study aimed to compare the development of crab and tree communities of two restored mangrove areas, one planted with Rhizophora mangle and the other naturally recovered, and also to compare the predation of Grapsid crab Goniopsis cruentata and the Ocypodid Ucides cordatus over the propagules of three mangrove trees: Rhizophora mangle, Avicennia schaueriana e Laguncularia racemosa. Specifically, we tested the hypothesis that Goniopsis predation is more important that Ucides predation, and that these consumers have antagonist effects over propagule consumption. In each area, 10 quadrates were selected at random to analyze tree richness, diameter, height, tree biomass and crab richness and density five years after restoration experiment start. Results show that tree height, biomass and crab density were significantly higher in artificially restored area. No significant differences were observed in crab species richness between areas, but higher tree richness was observed in self-recovered area. Results suggest that planting propagules of Rhizophora can significantly increase tree recovering if the aim was increase tree biomass and crab density, which can accelerate return of ecological functionality. Goniopsis is a more important propagule predator than Ucides both in natural and restored areas. The effects of Goniopis were higher in absence of Ucides, due to negative interactions among these two predator species. The preference of Goniopsis by Avicennia and Laguncularia can favor the dominance of Rhizophora observed in Neotropical mangroves. This study suggests that propagule predation by Goniopsis should be controlled in restoration programs, if dominance of Rhizophora is undesirable respect to more rich tree communities

Heurísticas usando construção de vocabuilário aplicadas ao problema da atribuição de localidades a anéis em redes SONET/SDH

The SONET/SDH Ring Assignment Problem (PALAS) treats to group localities in form of some rings, being respected the traffic's limitations of the equipment. Each ring uses a DXC (Digital Cross Connect) to make the communication with the others, being the DXC the equipment most expensive of the net, minimizing the number total of rings, will minimize the total net cost, problem's objective . This topology in rings provides a bigger capacity of regeneration. The PALAS is a problem in Combinatorial Optimization of NP-hard Class. It can be solved through Heuristics and Metaheuristics. In this text, we use Taboo Search while we keep a set of elite solutions to be used in the formation of a part of the collection of vocabulary's parts that in turn will be used in the Vocabulary Building. The Vocabulary Building will be started case Taboo Search does not reach the best solution for the instance. Three approaches had been implemented: one that only uses vocabulary's parts deriving of Taboo Search, one that it only uses vocabulary's parts randomly generated and a last one that it uses half come of the elite and half randomly generated

Recuperação e purificação de ramnolipídeos produzidos por pseudomonas aeruginosa P029-GVIIA utilizando melaço de cana como substrato

Biosurfactants are molecules produced by microorganisms mainly bacteria as Pseudomonas and Bacillus. Among the biosurfactants, rhamnolipids play an important role due to their tensoactive as well as emulsifying properties. Besides can be produced in a well consolidated way the production costs of biosurfactants are quite expansive mainly if downstream processing is goning to be considered. Actually, attention has been given to identification of biosurfactants as well as optimization of its fermentative processes including downstream ones. This work deals with the development of strategies to recovery and purification of rhamnolipids produced by Pseudomonas aeruginosa P029-GVIIA using sugar-cane molasses as substrate. Broth free of cells was used in order to investigate the best strategies to recovery and purification produced by this system. Between the studied acids (HCl and H2SO4) for the acid precipitation step, HCl was the best one as has been showed by the experimental design 24. Extraction has been carried out using petroleum ether and quantification has been done using the thioglycolic acid method. Adsorption studies were carried out with activated carbon in a batch mode using a 24 experimental design as well as combined with an hydrophobic resin Streamline Phenyl aiming to separate the produced biosurfactant. Biosurfactant partial identification was carried out using High Performance Liquid Chromatography (HPLC). Experiments in batch mode showed that adsorption has been controlled mainly by pH and temperature. It was observed a reduction of 41.4% for the liquid phase and the solid phase it was possible to adsorb up to 15 mg of rhamnolipd/g of activated carbon. The kinetics of adsorption has been well fitted to a pseudo-first order reaction with velocity constant (k1) of 1.93 x 10-2 min-1. Experiments in packed bed ranging concentration on eluent (acetone) has been shown the highest recovery factor of 98% when pure acetone has been used. The combined effect if using activated carbon with an hydrophobic resin Streamline Phenyl has been shown successful for the rhamnolipids purification. It has been possible to purify a fraction of the crude broth with 98% of purity when the eluted of activated carbon packed bed was used with pure acetone

Das relações entre imaginário e poesia na obra de Orides Fontela: o regime diurno da imagem

The present work seeks essentially to demonstrate how some anthropological structures of the imaginary, theorized by the French thinker Gilbert DURAND, projected themselves in a noticeable manner in the poetic work of the Brazilian poet Orides FONTELA. Chiefly we will demonstrate with great care in what way this projection and vivification occur through an imagination that not only materializes some fundamental archetypes of the human imagination, but also seeks to organize them through original poems in its form of presenting the poetic discourse, giving here a different contribution of the mythical or religious discourse, privileged places, since always, where the symbolic functions also manifest themselves

Detecção de predadores por dicromatas e tricromatas humanos e a sua implicação na evolução da visão de cores em primatas

Among placental mammals, primates are the only ones to present trichromatic color vision. However, the distribution of trichromacy among primates is not homogeneous: Old World primates shows an uniform trichromacy (with all individuals being trichromats) and New World primates exhibit a color vision polymorphism (with dichromatic males and dichromatic or trichromatic females). Visual ecology studies have investigated which selective pressures may have been responsible for the evolution of trichromacy in primates, diverging from the dichromat standard found in other mammals. Cues associated with foraging and the socio-reproductive status were analyzed, indicating a trichromatic advantage for the rapid detection of visually conspicuous objects against a green background. However, dichromats are characterized by an efficient capture of cryptic and camouflaged stimuli. These advantages regarding phenotype may be responsible for the maintenance of the visual polymorphism in New World primates and for the high incidence of color blindness in humans (standing around 8% in Caucasian men). An important factor that has not yet been experimentally taken into account is the predation risk and its effect on the evolution of trichromacy in primates. To answer this question, we prepared and edited pictures of animals with different coats: oncillas (Leopardus spp.), puma (Puma concolor) and ferret (Galictis cuja). The specimens were taxidermized and the photographs were taken in three different vegetation scenarios (dense forest, cerrado and grassland). The images of the predators were manipulated so that they fit into two categories of stimulus size (small or large). After color calibration and photo editing, these were presented to 40 humans (20 dichromats and 20 trichromats) by a computer program, which presented a set of four photos at a time (one picture containing the taxidermized animal amid the background vegetation and three depicting only the background vegetation) and recorded the response latency and success rate of the subjects. The results show a trichromatic advantage in detecting potential predators. The predator detection was influenced by the background, the predator species, the dimension of the stimulus and the observer s visual phenotype. As humans have a high rate of dyschromatopsias, when compared to wild Catarrhini or human tribal populations, it is possible that the increased rate of dichromats is a result of reduced pressure for rapid predator detection. Since our species came to live in more cohesive groups and resistant to attack by predators, with the advent of agriculture and the formation of villages, it is possible that the lower risk of predation has reduced the selection in favor of trichromats

Vinculando a etnoictiologia às evidências biológicas para explicar o declínio da riqueza da ictiofauna neotropical

The diversity of fish species from South America has been affected by various anthropogenic practices. Some studies have reported the influence that illegal transferring or introduction of exotic species have on the trophic webs of continental lakes. The loss of diversity on fish populations and consequent impacts on fishery are commonly evidenced in these cases. The Brazilian Northeast has ponds for which exotic Amazonian species were transferred as Extremoz Lake. These environments serve as study models for comparison and investigation about the possible impacts of these introductions. We tested the hypothesis that loss of species that this trend can be related with the insertion of the genus Cichla, commonly documented as top predator in its endemic environment. Possible structural causes that interfere in other processes such as migration were also investigated. Thus, the local ecological knowledge of fishermen and a current ecotrophic model were used. We took samples of phytoplankton, zooplankton and fishes during two annual cycles. Concurrently, we made interviews with the fishing community. In fact, there are relations between the loss of fish and the insertion of peacock bass in Extremoz Lake. However, Cichla kelberi was not indicated as primary factor to explain fish species decline. The construction of bridges located in the Rio Doce was main factor for respondents and what explains loss of species. The migration of saltwater fish and / or from the river to Extremoz Lake is hindered by the unsuitability of the crossing-streams that are under these structures. According to the ecotrophic model Hoplias malabaricus was considered key-species and Cichla kelberi top predator. This last trend was similarly noticed in the stomach and local ecological knowledge of fishermen analysis. Overfishing simulations to Cichla kelberi resulted that only raising its captures in 200%, other native species would increase their biomass values only 15 to 30% (in 6 years).The negative effects of the alien species introduction without prior studies and lack of investments in appropriating these constructions to the needs of the fish fauna structures seem to act simultaneously. Both are causing the decline of fish species richness and consequent local artisanal fishery collapse