916 resultados para Atrativos naturais


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Most of ontogenetic studies on circadian timing system have been developed on infants, adults and elderly. The puberty has not been a stage of life few studied, except for researches in human adolescents, that presents phase delay in sleep-wake cycle. However, few studies have focused on the basis of this circadian change due to methodological difficulties. Thus, an animal model to study the sleep-wake cycle at puberty is essential. In the common marmoset, a social primate, the circadian activity periodicity stabilizes around 4 months (juvenile stage) and the 8h period component has a seasonal variation. Puberty stage of this species begins near the 8th month of age in males and near the 7th month in females with 7 months of duration. With the aim to characterize the circadian motor activity rhythm during puberty in marmosets (Callithrix jacchus) the motor activity was continuous registered by actiwatches in 6 animals between 5-12 months. Since the social factor influence the behavior of this specie, behavioral observations were realized in 30 minutes windows twice/week to a general evaluation of the influence social interactions dynamic across experiment. Determination of puberty onset was done by fecal progesterone and estrogens in females, and androgens in males. From the analysis of the multiple regression test was selected a model that evaluate age and seasonal variables effect on the activity rhythm according to the higher explanation coefficient. The total activity was the only parameter influenced by age. Moreover, the activity onset was the parameter more explained by the model, and the sunrise was the factor that most influenced it. After the puberty onset, 2 dyads advanced the activity onset. The activity total decreased in 1 dyad and increased in 2 dyads. This increase may be related to the birth of infants in these families. The motor activity circadian component stabilized later in 1 dyad, coinciding with the puberty onset of these animals, while bimodality, caused by the 8 h component, was modulated by seasonality. The agonistic behavior was not evaluated due to reduced number of events. There were changes across ages in affiliative behavior of contact in 1 dyad, grooming done in 1 animal and grooming received in 2 animals. Although there is evidence of puberty effect on the activity motor rhythm, the photoperiodic fluctuations influenced the rhythm. Therefore is not possible to affirm if the puberty modulate the activity rhythm in marmosets

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This study aimed at exploring and describing children s perceptions in threatened natural settings, specifically, the Rain Forest in Brazil. Several studies point to the significance of perceptions for people s pro-environmental attitudes and actions. We try to understand the person-environment interaction from an ecological perspective, and we present theoretical references for the understanding of how crucial nature is for psychological development and well-being. The children s drawings, individual interviews, discussion groups, photographies and informal and indirect sources, as teachers, brought material for the analysis. Participated in our study, carried on through a multi-method strategy, 209 children from six to eleven years old, living in the neighborhood of the Biological Reserve of Una, State of Bahia, created to protect Rain Forest fragments. The Rain Forest landscape is well portrayed in children s drawings, the vegetal elements prevailing over artificial and human elements. The figured plants and trees, however, are pointed with no precision as to their species. Most of the defined species are eatable. The children seem to be aware of the environment degradation, and of the importance of its conservation, but they describe episodes of hunting and feeding wild threatened animals. Our results indicate a utilitarian trend in the perception of living beings, in terms of their immediate usefulness for people. The multimethod approach seems to be appropriate to the complexity of the theme; the methodological strategies were well accepted by the children, offering them opportunities to express themselves. We observed how children, in different life phases, organize natural elements and processes in their drawings, and how these images relate to the local landscape. We discuss the results in the light of theoretical references of personenvironment studies and from previous investigations about children s perceptions of natural environment

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Sweeteners provide a pleasant sensation of sweetness that helps the sensory quality of the human diet, can be divided into natural sweeteners such as fructose, galactose, glucose, lactose and sucrose, and articial sweeteners such as aspartame, cyclamate and saccharin. This work aimed to study the thermal stability of natural and artificial sweeteners in atmospheres of nitrogen and syntetic air using thermogravimetry (TG), derivative thermogravimetry (DTG), Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC). Among the natural sweeteners analyzed showed higher thermal stability for the lactose and sucrose, which showed initial decomposition temperatures near 220 ° C, taking advantage of the lactose has a higher melting point (213 ° C) compared to sucrose (191 ° C). The lower thermal stability was observed for fructose, it has the lowest melting point (122 °C) and the lower initial decomposition temperature (170 °C). Of the artificial sweeteners studied showed higher thermal stability for sodium saccharin, which had the highest melting point (364 ° C) as well as the largest initial decomposition temperature (466 ° C under nitrogen and 435 ° C in air). The lower thermal stability was observed for aspartame, which showed lower initial decomposition temperature (158 ° C under nitrogen and 170 ° C under air). For commercial sweeteners showed higher thermal stability for the sweeteners L and C, which showed initial temperature of thermal decomposition near 220 ° C and melting points near 215 ° C. The lower thermal stability was observed for the sweetener P, which showed initial decomposition temperature at 160 ° C and melting point of 130 °C. Sweeteners B, D, E, I, J, N and O had low thermal stability, with the initial temperature of decomposition starts near 160 °C, probably due to the presence of aspartame, even if they have as the main constituent of the lactose, wich is the most stable of natural sweeteners. According to the results we could also realize that all commercial sweeteners are in its composition by at least a natural sweeteners and are always found in large proportions, and lactose is the main constituent of 60% of the total recorded

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Among the new drugs launched into the market since 1980, up to 30% of them belong to the class of natural products or they have semisynthetic origin. Between 40-70% of the new chemical entities (or lead compounds) possess poor water solubility, which may impair their commercial use. An alternative for administration of poorly water-soluble drugs is their vehiculation into drug delivery systems like micelles, microemulsions, nanoparticles, liposomes, and cyclodextrin systems. In this work, microemulsion-based drug delivery systems were obtained using pharmaceutically acceptable components: a mixture Tween 80 and Span 20 in ratio 3:1 as surfactant, isopropyl mirystate or oleic acid as oil, bidistilled water, and ethanol, in some formulations, as cosurfactants. Self-Microemulsifying Drug Delivery Systems (SMEDDS) were also obtained using propylene glycol or sorbitol as cosurfactant. All formulations were characterized for rheological behavior, droplet size and electrical conductivity. The bioactive natural product trans-dehydrocrotonin, as well some extracts and fractions from Croton cajucara Benth (Euphorbiaceae), Anacardium occidentale L. (Anacardiaceae) e Phyllanthus amarus Schum. & Thonn. (Euphorbiaceae) specimens, were satisfactorily solubilized into microemulsions formulations. Meanwhile, two other natural products from Croton cajucara, trans-crotonin and acetyl aleuritolic acid, showed poor solubility in these formulations. The evaluation of the antioxidant capacity, by DPPH method, of plant extracts loaded into microemulsions evidenced the antioxidant activity of Phyllanthus amarus and Anacardium occidentale extracts. For Phyllanthus amarus extract, the use of microemulsions duplicated its antioxidant efficiency. A hydroalcoholic extract from Croton cajucara incorporated into a SMEDDS formulation showed bacteriostatic activity against colonies of Bacillus cereus and Escherichia coli bacteria. Additionally, Molecular Dynamics simulations were performed using micellar systems, for drug delivery systems, containing sugar-based surfactants, N-dodecylamino-1-deoxylactitol and N-dodecyl-D-lactosylamine. The computational simulations indicated that micellization process for N-dodecylamino-1- deoxylactitol is more favorable than N-dodecyl-D-lactosylamine system.

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This study aimed to analyze the phytoremediation potential of Eichhornia crassipes in natural environments, optimize the extraction process of crude protein from plant tissue and, obtain and characterize this process in order to determine its viability of use instead of the protein sources of animal and/or human feed. For this, it has been determined in Apodi/Mossoró river water the concentration of ammonium ions, nitrite, nitrate, calcium, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, aluminum, cádmium, lead, and total chromium; It was determined in plant tissue of aquatic macrophytes of Eichhornia crassipes species present in Apodi/Mossoró River the moisture content, ash, calcium, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, aluminum, cadmium, lead, total chromium, total nitrogen and crude protein. It was also determined the translocation factor and bioaccumulation of all the quantified elements; It was developed and optimized the extraction procedure of crude protein based on the isoelectric method and a factorial design 24 with repetition; It was extracted and characterized the extract obtained by determining the moisture content, ash, magnesium, potassium, iron, copper, manganese, zinc, nickel, cobalt, sodium, cadmium, total nitrogen and crude protein. And finally, it was also characterized the protein extract using Thermogravimetric Analysis (TG), Derived Thermogravimetric (DTG), Differential Scanning Calorimetry (DSC), Infrared Spectroscopy (FT-IR) and jelly-like electrophoresis of polyacrylamide (SDS -PAGE) to assess the their molecular weights/mass. Thus, from the results obtained for the translocation and bioaccumulation factors was found that the same can be used as phytoremediation agent in natural environments of all quantified elements. It was also found that the developed method of extraction and protein precipitation was satisfactory for the purpose of the work, which gave the best conditions of extraction and precipitation of proteins as: pH extraction equal to 13.0, extraction temperature equals 60 ° C, reaction time equals to 30 minutes, and pH precipitation equals to 4.0. As for the extract obtained, the total nitrogen and crude protein were quantified higher than those found in the plant, increasing the crude protein content approximately 116.88% in relation to the quantified contente in the vegetal tissue of macrophyte. The levels of nickel and cadmium were the unique that were found below the detection limit of used the equipment. The electrophoretic analysis allowed us to observe that the protein extract obtained is composed of low polypeptide chains by the molecular and phytochelatins, with 6 and 15 kDa bands. Analysis of TG, DTG, DSC and FT-IR showed similarities in protein content of the obtained extracts based on different collection points and 9 parts of the plant under study, as well as commercial soy protein and casein. Finally, based on all these findings, it was concluded that the obtained extract in this work can be used instead of the protein sources of animal feed should, before that, test its digestibility. As human supplementation, it is necessary to conduct more tests associated with the optimization process in the sense of removing undesirable components and constant monitoring of the water body and the raw material used

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The study presents an approach on planning, sociospatial transformations and public touristic policies implemented between 2000 and 2010 in Caicó, encompassing people from the government, private sector and the population of the municipality and informal traders who use the leisure facilities and services arranged in place. As the main goal, the research intends to analyze the performance of public and private sectors correlated to the touristic activity in Caicó city and their reflections in the process changes sociospatial. The dissertation is structured in order to carry out an investigation into the role of public policies to the development of a location with touristic potential, in this case, the municipality of Caicó; to investigate public policies implemented in the touristic industry of Rio Grande do Norte, particularly the actions of PRODETUR-Nordeste focused on the development of the tourism in the countryside, affecting particularly the region of Seridó region and the municipality of Caicó, and, finally, to check the main changes sociospatial verified in Caicó between 2000 and 2010. Cultural issues and certain natural beauties can be seen as attractions that can attract tourist demand, taking into consideration the awakening increasingly more evident quest by the tourist for knowledge of the peculiarities of the region. Several authors have worked in this view, pointing to the cultural aspects of the region as elements that are able to boost the touristic activity. The questions raised in this study was based on a literature, based mainly on authors like Beni, Dias, Cruz, Azevedo and Morais. To obtain the necessary data in the analysis, the methodological procedures used in intensive direct observation, using interviews, applied together with the public representatives who are acting as leaders of the political actions related to tourism in the municipality and members of the private sector related to tourism services such as lodging establishments, food and travel agency and, finally, the local people and informal traders benefited directly or indirectly, with the touristic resources and structure. These research agents were investigated by means of structured forms such as support for analysis. Was detected in the survey that the leisure facilities and services installed in the last decade in the city of Caico has a priority the population of the municipality, is necessary to emphasize that the residents interviewed perceive the importance of these tools for tourist activity. It was also found that the public sector is the main responsible for the observed changes. Therefore, proved to be relevant to study the role public private sector partnerships and population influences, considering that this analysis may contribute to the work of researchers, public administrators and businessmen, may serve as a norteador for planning and development of tourism in the city of Caico

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Amenities value provided by green areas, sea, river and natural landscapes are hardly perceived and incorporated on urban planning and development. In this work, distance and view to protected and non-protected green areas, sea and river were evaluated as to how they increase the housing prices in Natal. Hedonic pricing methods were used with linear models to estimate the marginal implicit value of environmental, residential and neighborhood features. Results on Chapter 1 demonstrate the view to the sea and protected natural areas were largely capitalized on housing prices, while non-protected natural areas didn t display such effect. Housing prices also increase when close to the sea or to parks entrance. However, housing prices fall when houses are near non-protected natural areas. When estates with sea view were excluded, the protected natural areas view and a longer distance to non-protected natural areas increased dwelling prices. Results on Chapter 2 point the sea view as an hedonic variable the contributes strongly to the property selling prices, even though not always as the greatest contributor; furthermore, the property proximity to Dunas Park or City of the Park entrance increases its price, as does closeness to Dunas Park, view to City of the Park or Dunas Park. On the other hand, selling prices diminish if properties are close to City of the Park or Morro do Careca. Results on this study confirm the hedonic pricing methods is an important intrument, capable of revealing to popullation the importance of enviromental amenities and can be used by public managers for creating public policies for conservation and restoration projects

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Photography is a resourse of the most used and effective marketing, besides being an polysemic art, boundless sense; this allows for different readings. Nevertheless, there are those who, through the control and supervision, try to organize its meaning, such as the marketing companies. Others, such as artists, are the responsibility of the observers to give their work some understanding. Resorting a photographic iconography of the tourist attractions of the city of João Pessoa in Brazil from 2005 to 2010. This survey selected images published in catalogs supported by the Fundo de Incentivo a Cultura (FIC) and the Empresa Paraibana de Turismo (PBTUR). The central idea of this qualitative research is the assumption that, in general, tourists crave, even unconsciously, a reality of a tourist attraction motivated by photographic image conveyed the travel market, meanwhile, emphasizes that the art market, the same attraction is exposed and uncovered. Thus it is argued, by photos, such as environmental and sociocultural characteristics are commodified by these organs that have different purposes is not exclusive, given that the FIC supports art and PBTUR sponsors the tourism. Beyond the iconography used for cataloging and photographic analysis, interviews were conducted by the method of visual narratives in ordes to approximate the data with the view of tourists and photographers. In that resulted in a refletion on the current imagistic process involving the release of the tourist destinations in order to be allowed on a critical reading of photographic production and market resources to marketing and promoting the art of the city. It was observed that both the art and photography marketing acquire different symbolic values with respect to their markets promoted by the catalogs analyzed.

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The human being has a fundamental role in issues concerning scarcity of energy resources as well as in the success of technologies which favor the use of renewable sources, such as wind energy. But what does wind energy mean for people? What are the psychological meanings concerning this term? Aiming to answer these questions, the general objective of this dissertation was to identify and to analyze the knowledge about wind energy taking into account a network of psychological meanings. One hundred and ninety one (191) university students from Natal-RN participated in the study, being male the majority (53%); aged between 17 and 51 years old (M=23.3 years; SD=5.7). Participants responded to self reports using the Natural Semantic Networks (NSW) technique, as well as to several sociodemographic questions. The results showed a consistent, positive and useful general semantic network. In this semantic network, knowledge about wind energy was represented by words that correspond to the appeal of (pro) environmental stance (e.g., clean and nature), that evinced both the technological aspect (e.g., force) and the economic aspect (e.g., economy). Results from different groups were also analyzed. The first set of groups (non-environemental and environmental) was divided considering the course (e.g., ecology and economy). The second set of groups(non-caretaker and caretaker) was divided based on the practice of environmental care expressed. Subtle differences were observed in the semantic networks of caretakers, who emphasized environment, an attribute not mentioned by non-caretakes. This indicates a construction of knowledge that is influenced by the presence or absence of the environmental commitment. Such findings may be useful in the construction of instruments for surveys and in the development of public and educational policies. Additionally, they may assist the media towards a more objective performance concerning wind energy

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O objetivo deste trabalho foi avaliar os efeitos do ácido oxálico e de óleos essenciais de plantas no controle da infestação pelo ácaro Varroa destructor em colônias de Apis mellifera africanizadas. O experimento foi realizado em delineamento inteiramente casualizado, em 30 colônias, com seis tratamentos e cinco repetições. As colmeias foram tratadas com óleos essenciais de arruda (Ruta graveolens), eucalipto (Eucalyptus spp.) e hortelã (Mentha piperita), além de timol, ácido oxálico e do tratamento controle sem aplicação de produtos. Foram avaliadas a mortalidade de varroas e as taxas de mortalidade de crias e de infestação de varroas em crias e em abelhas adultas, antes e depois da aplicação de cada produto. O ácido oxálico e os óleos de arruda, timol, eucalipto e de hortelã reduziram a mortalidade de crias parasitadas pelo ácaro em 92,1, 83,3, 81,7, 86,4 e 81,3%, respectivamente. O tratamento com ácido oxálico reduziu em 87,4% a infestação de varroas em abelhas adultas. O uso desses produtos é eficiente na redução da mortalidade de crias de A. mellifera parasitadas por V. destructor.

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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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Os valores têm sido considerados importante conteúdo de ensino, sobretudo ao tratarmos de certas temáticas, como a ambiental. Procurando analisar o tratamento dado à dimensão valorativa da temática ambiental em três coleções de Ciências Naturais voltadas às séries finais do Ensino Fundamental verificamos a predominância da visão antropocêntrica, sendo a natureza valorizada em função de sua utilidade para o ser humano. O predomínio da valorização do conhecimento científico em detrimento de outras formas de conhecimento, da ação humana individual em detrimento da coletiva e a simples apresentação de leis ambientais foram outros aspectos problemáticos encontrados. Uma das coleções, entretanto, além de valorizar o trabalho coletivo dos alunos, também se destacou pela maior ênfase dada à dimensão estética, implicando uma visão de mundo menos utilitarista e um tratamento mais adequado do conteúdo valorativo da temática ambiental.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)