91 resultados para Neuropogon aurantiaco ater


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This work reports the separation of phenolic compounds present in the metabolic extract of the lichen Neuropogon aurantiaco-ater (Usniaceae). The crude extract was fractionated by droplet counter-current chromatography using a solvent mixture of high polarity (chloroform:methanol:water at 43:37:20, in ascending mode). The separation resulted in the isolation of usnic and protocetratic acid, which were identified by TLC, HPLC, and NMR tests.

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Usnea species of the Neuropogon group are amongst the most widespread and abundant macrolichens in Antarctic regions. Four principal species, U. antarctica, U. aurantiaco-atra, U. sphacelata and U. subantarctica, have been described on morphological grounds. However, identification to species level is often difficult and atypical morphologies frequently arise. Over 400 specimens were collected on the Antarctic Peninsula and Falkland Islands. Both morphological and molecular characters (ITS and RPB1) were used to compare samples to clarify taxonomic relationships. Morphological characteristics used included presence of apothecia, apothecial rays, soredia, papillae, fibrils, pigmentation and the diameter of the central axis as a proportion of branch diameter. Results revealed a very close relationship between U. antarctica and U. aurantiaco-atra, suggesting that they might constitute a species pair or be conspecific. Usnea sphacelata was comprised of at least two genetically distinct groups with no clear differences in morphology. One group included the first reported fertile specimen of this species. Usnea subantarctica was phylogenetically distinct from the other main Antarctic Usnea species, but clustered with U. trachycarpa. Genetic variation was evident within all species although there was no clear correlation between geographic origin and genetic relatedness. Phylogenetic analyses indicated that species circumscription in the Neuropogon group needs revision, with the principal species being non-monophyletic. None of the morphological characters, or groups of characters, used in this study proved to be completely unambiguous markers for a single species. However, axis thickness was supported as being informative for the identification of monophyletic lineages within the group.

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Arion ater barea, ingurumeneko kutsaduraren organismo behale moduan erabiltzen da, horregatik, baldintza normaletan liseriketan zehar liseri-guruina nola aldatzen den aztertzea interesgarria izan daiteke; izan ere, liseriketa dela eta ematen diren aldaketak eragina izan dezakete animaliotan neurtzen den hainbat parametrotan. Liseri-guruina, azino deituriko unitate funtzionalez osatua dago eta liseriketaz eta liseriketarako beharrezkoak diren sustantzien jariapenaz arduratzen da. Liseri-epitelioan, hiru zelula mota bereizi dira: liseri-, eskrezio- eta kaltzio-zelulak. Hauen kopuruak, zein epitelioaren lodiera eta argiaren tamaina, liseriketa fasearen arabera aldatzen dira; aldaketa hauek, zelula mota bakoitzaren funtzioarekin erlazionatuak egonik. Honetaz gain, liseriketa aurrera doan heinean, mukopolisakaridoen garraioa dagoela ikusi da; ondorioz, liseri-traktuko, odol hodietako eta liseri-guruineko mukopolisakaridoen kopuruan desberdintasunak agertu dira.

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Due to the appreciation of family farming by the Brazilian Federal Government, the Technical Assistance and Rural Extension was induced to restructure and act in a more participative way, culminating in the National Policy of Technical Assistance and Rural Extension (PNATER), changing the profile of technology transfer and knowledge (diffusionism) for an action that uses participatory methodologies focused on exchange of knowledge between farmers and technicians. The process of discussion of the trends of ATER brought the New ATER , with the recognition of agroecology as the main guidance. This research aimed to analyze methods of public ATER developed by institutions of Rio Grande do Norte, under the guidance of New ATER. The research is qualitative. Secondary data were collected through documental research and literature. Primary data were collected through a set of interviews applied to representatives of public institutions ATER, namely EMATER-RN, Diaconia and AACC and representatives of organizations that receive public ATER. The research showed the difficulties of EMATER-RN in implementing of New ATER due to lack of infrastructure and low adherence of the new form of technical assistance and rural extension. It was shown also that the AACC and Diaconia act with ATER through projects with implementation deadlines set, often interrupting ATER while communities are still in need of assistance

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It is believed that habitat heterogeneity can change the extent of predator-prey interactions. Therefore, in this study we examined the effect of habitat heterogeneity (characterized here as an addition of refuge) on D. ater predation on M. domestica. Predation of D. ater on M. domestica larvae was carried out in experimental habitats with and without refuge, and examined at different prey densities. The number of prey eaten by beetles over 24 h of predator-prey interaction was recorded, and we investigated the strength of interaction between prey and predator in both experimental habitats by determining predator functional response. The mean number of prey eaten by beetles in the presence of refuge was significantly higher than in the absence of refuge. Females had greater weight gains than males. Logistic regression analyses revealed the type II functional response for both experimental habitats, even though data did not fit well into the random predator model. Results suggest that the addition of refuge in fact enhanced predation, as prey consumption increased in the presence of refuge. Predators kept in the presence of refuge also consumed more prey at high prey densities. Thus, we concluded that the addition of refuge was an important component mediating D. ater-M. domestica population interactions. Refuge actually acted as a refuge for predators from prey, since prey behaviors detrimental to predators were reduced in this case.

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Nesticodes rufipes is widely distributed in tropical and subtropical regions, being strongly associated with humans. However, few behavioral and ecological studies have investigated interspecific interactions between these spiders and insects of medical and veterinary importance. Here, we have investigated prey choice by N. rufipes when two different prey species, Musca domestica and Dermestes ater, were offered simultaneously. We also quantified the capture of these prey types by this predator in a poultry house and analyzed the association between prey-choice with physical characteristics of the prey. Finally, we discuss whether there is an antagonistic intraguild interaction in such a system composed of N. rufipes (top predator), D. ater (predator of larvae of M. domestica and prey of N. rufipes) and M. domestica (N. rufipes' prey). We found that Musca domestica were more abundant than D. ater in N. rufipes webs in the poultry house. Spiders given a choice of adults of M. domestica plus adults of D. ater, and also on adults plus larvae of M. domestica, preyed more on adult flies than on the other prey types. This preference was probably associated with the lesser mass and shorter lengths of adult flies. Our experiments demonstrated that the predation impact of N. rufipes on D. ater is low when compared to M. domestica. This result provides evidence that an antagonistic interaction between these predators does not occur, suggesting that they are in fact acting either synergistically or additively on M. domestica prey.

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Descreve-se o isolamento e a identificação do vírus rábico em morcegos insetívoros Molossus ater, no Estado de São Paulo, nos municípios de Araçatuba, Penápolis e São José do Rio Preto. A maioria dos exemplares foi capturada ainda com vida, não havendo, porém, contato com pessoas ou animais. O diagnóstico foi realizado pelas provas de imunofluorescência direta e inoculação intracerebral em camundongos.

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It is well known that a predator has the potential to regulate a prey population only if the predator responds to increases in prey density and inflicts greater mortality rates. Predators may cause such density-dependent mortality depending on the nature of the functional and numerical responses. Yet, few studies have examined the relationship between the addition of refuges and the characteristic of functional response fits. We investigated whether addition of a refuge changed the type of functional response exhibited by Dermestes ater on Musca domestica, comparing the inherent ability of D. ater to kill houseflies in the absence and in the presence of refuge. An additional laboratory experiment was also carried out to assess handling and searching times exhibited by D. ater. Logistic regression analyses revealed a type III functional response for predator-prey interaction without refuge, and results were described by the random predator equation. The mean number of prey killed did not differ between experimental habitats, indicating that the addition of refuge did not inhibit predation. However, predators that interacted with prey without refuge spent less time searching for prey at higher densities, increasing predatory interaction. We concluded that this interaction may be weak, because data from experiments with refuge fitted poorly to models. However, the high variability and the nonsignificance of the data from the experiment with refuge show the importance of refuge for promoting spatial heterogeneity, which may prevent prey extinction.

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A assistência técnica e extensão rural no Brasil historicamente tem sido tratada como instrumento de modernização do meio rural brasileiro, ou seja, da transformação do agricultor “atrasado” em agricultor “moderno”. Da mesma forma o técnico que nela atua finda por ser também visto como instrumento, objeto, nunca como ator neste processo. Este trabalho tem o objetivo de colocar o técnico no centro da questão, verificando as possibilidades e modos de construção da sua identidade profissional no contexto da ATER surgido na mesorregião sudeste do Pará a partir de 1997. Este contexto apresenta demandas por competências para as quais o técnico não foi formado nem socializado, como a exigência de uma postura participativa com relação ao agricultor e capacidade de pesquisa, o que finda por provocar conflitos entre o novo perfil requerido e a forma de socialização e formação do técnico. A conclusão é que o ambiente regional é extremamente favorável à atuação do técnico na construção e reconstrução de sua identidade profissional, o que não ocorria nos modelos anteriores de ATER, porém a formação tecnicista acaba por impor barreiras à construção do comportamento participativo no que se re fere às inovações técnicas especificamente.

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Il progetto di tesi elaborato tratta uno dei temi più attuali nell’ambito architettonico, l’efficienza energetica degli edifici. La tesi, sviluppata all’interno del Laboratorio di Laurea in Architettura Sostenibile, tratta un caso peculiare, in quanto riguarda il recupero di un’opera incompiuta, un comparto di 24 alloggi di Social Housing situato nella città di Rovigo. Il proprietario dell’impianto, l’ente pubblico per l’edilizia sociale ATER, ha posto delle direttive qualitative e quantitative per portare a compimento l’opera. Preso atto di queste disposizioni, e a seguito di accurate analisi di tipo tecnico, morfologico e demografico, sono state definite accurate strategie progettuali, riguardanti la definizione di alloggi idonei alla richiesta dell’ente e alla conformazione demografica della città, il recupero della preesistenza e lo sviluppo di una architettura energicamente efficiente.

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This article aims to identify how the Foodstuff Acquisition Program has influenced market creation for family farmers in two Brazilian states - Minas Gerais e Bahia and also the limitations and benefits of the program from the point of view of the extension agents. A bibliographic research and a quantitative exploratory study were conducted, questionnaires were sent to extension agents who work for public rural extension agencies, municipalities, NGOs, cooperatives and producers' associations, during the year 2010-2011.