947 resultados para empty sella
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Mangas 'Tommy Atkins' produzidas na região de Ibirá, São Paulo, foram pulverizadas na pré-colheita com cloreto de cálcio, nas concentrações de 0,0%, 2,5% e 5,0%, em três épocas de seu desenvolvimento (40; 60 e 90 dias após a floração) a fim de verificar a influência do cálcio na estrutura da parede celular destes frutos através de microscopia eletrônica de transmissão, imediatamente após a colheita e depois de 35 dias de armazenamento. Para fixar o material da polpa, utilizou-se metodologia descrita por Jacob e Gowanlock (1995). Nas condições experimentais, verificou-se que os frutos do tratamento-controle (sem cloreto de cálcio), no dia da colheita, já apresentavam desestruturação da parede celular e dissolução da lamela média (LM). A degradação da parede celular ocorre inicialmente na LM, levando à formação de espaços vazios bastante distintos, apresentando uma dissolução ainda maior, com o armazenamento prolongado (35 dias). Os frutos tratados com cloreto de cálcio a 5,0% apresentaram uma LM bem definida e ausência de espaços vazios, mesmo após o armazenamento, mostrando ser uma concentração efetiva na preservação da lamela média.
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The search for sustainable technologies that can contribute to reduce energy consumption is a great challenge in the field of insulation materials. In this context, composites manufactured from vegetal sources are an alternative technology. The principal objectives of this work are the development and characterization of a composite composed by the rigid polyurethane foam derived from castor oil (commercially available as RESPAN D40) and sisal fibers. The manufacture of the composite was done with expansion controlled inside a closed mold. The sisal fibers where used in the form of needlepunched nonwoven with a mean density of 1150 g/m2 and 1350 g/m2. The composite characterization was performed through the following tests: thermal conductivity, thermal behavior, thermo gravimetric analysis (TG/DTG), mechanical strength in compression and flexural, apparent density, water absorption in percentile, and the samples morphology was analyzed in a MEV. The density and humidity percentage of the sisal fiber were also determined. The thermal conductivity of the composites was higher than the pure polyurethane foam, the addition of nonwoven sisal fibers will become in a higher level of compact foam, reducing empty spaces (cells) of polyurethane, inducing an increase in k value. The apparent density of the composites was higher than pure polyurethane foam. In the results of water absorption tests, was seen a higher absorption percent of the composites, what is related to the presence of sisal fibers which are hygroscopic. From TG/DTG results, with the addition of sisal fibers reduced the strength to thermal degradation of the composites, a higher loss of mass was observed in the temperature band between 200 and 340 °C, related to urethane bonds decomposition and cellulose degradation and its derivatives. About mechanical behavior in compression and flexural, composites presented a better mechanical behavior than the rigid polyurethane foam. An increase in the amount of sisal fibers induces a higher rigidity of the composites. At the thermal behavior tests, the composites were more mechanically and thermally resistant than some materials commonly used for thermal insulation, they present the same or better results. The density of nonwoven sisal fiber had influence over the insulation grade; this means that, an increaser in sisal fiber density helped to retain the heat
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O trabalho teve como objetivo avaliar o efeito de doses de fósforo aplicadas via solo, sobre os componentes de produção, produtividade e qualidade fisiológica de sementes de feijão, cv. IAC Carioca. Foram avaliadas seis doses de fósforo (0, 30, 60, 90, 120 e 150kg.ha-1 de P2O5) sob o delineamento experimental em blocos casualizados, com quatro repetições, em Latossolo Vermelho com baixo teor de fósforo (6mg.dm-3), em condições de campo. No momento da colheita, avaliaram-se estande final de plantas, altura da inserção da primeira vagem, comprimento das vagens, número de vagens/planta, número de sementes/vagem, número de lóculos/vagem, número lóculos vazios/vagem, número de lóculos com sementes/vagem e massa de 100 sementes. A produtividade de sementes foi determinada com base na produção das duas linhas centrais de cada parcela, com teor de água corrigido para 13%. A qualidade fisiológica das sementes foi avaliada pelos testes de germinação, primeira contagem de germinação, envelhecimento acelerado, condutividade elétrica, emergência de plântulas no campo e massa de matéria seca de plântulas. A adubação fosfatada com 150kg.ha-1 de P2O5 aumentou o número de vagens/planta e o número de sementes/planta. Os demais componentes de produção e a produtividade de sementes não foram alterados pela aplicação de fósforo. As doses de fósforo não alteraram a qualidade fisiológica das sementes de feijão, cv. IAC Carioca.
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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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The damselfish, Stegastes fuscus Cuvier, 1830 (Osteichthyes: Perciformes: Pomacentridae), is abundant in the coastal reefs of Búzios Beach, Rio Grande do Norte, Brazil and they play an important role in the reef community ecology. The present study investigated the feeding strategy of this species considering the food habits and morfo-histology of the digestive tract. Influence of the environmental correlates such as temperature, rainfall and luminosity in the tidal rock pools were studied. The fish were captured on a monthly basis from September 2004 to August 2005, during which period 842 individuals of S. fuscus were captured, 125 males, 437 females and 280 individuals without sex identification. The sex ratio observed was 1 M : 3,5 F. The total body length of males varied from 3.6 to 11.3 cm, with a mean of 7.77 cm; that of females varied from 2.9 to 11.4 cm, with a mean of 7.85 cm, and that of sex grouped individuals varied from 2.9 to 11.4 cm, with a mean of 7.83. However, there was no difference between males and females in total body length. This species presented a positive alometric growth and the equations obtained for the relation between body mass and total body length were: Wt =0,0174Lt 3,1123 for males; Wt =0,0137Lt 3,2294 for females and Wt = 0,0148Lt 3.1928 for sex grouped individuals. The relation between total body length and standard length was L t = 1 ,3223Ls + 0,1527 for sex grouped individual s. February to August was associated to a long period of gonadal resting. The fish spawned during January and in September -October. The frequency of fish with empty stomachs occurred during August to December, whereas frequency of fish with food contents i n stomachs occurred during January to July. This species is considered as a preferential herbivore based on the volume of macroalgae in its diet composition. The morfo -histological aspects of S. fuscus confirm herbivory. Among the environmental factors con sidered only rainfall showed a correlation with the feeding habits of this species
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Parental care in mammals is influenced by somatosensory stimuli from infants, such as vocalization and sight and by changes in the hormone levels of caretakers. The aim of this study was to evaluate the behavioral and hormonal responses of twelve non reproductive adult male common marmosets (Callithrix jacchus) to infant cues, vocalization recordings, sight and physical contact with newborn. Six out of twelve males had previous experience in caretaking. In article 1, adult males were exposed to newborn vocalizations for 10 minutes. On control condition no sound was presented. In article 2, males were tested on two conditions: a) Control: an empty acrylic transparent box (test box) was placed in male s cage for 15 minutes, and b) Experimental: males were exposed to newborns into a closed text box for 15 minutes. The cage was kept closed to prevented from tactile, smell and acoustic stimulation by the infant on common marmoset males. In article 3, males were exposed to an open or closed text box, which allowed or not their access to and social interaction with the infants. After each observation sessions, blood samples were collected to evaluate the cortisol levels of males. In all studies, behavioral response of adult males was significantly modified by newborns sight, vocalization and physical contact. Males approached and spent more time near the sound source and showed an increase in locomotion during sound exposure. Furthermore, males approached, smelled and spent more time near the test box when the newborn was inside it. There was no difference in behavioral pattern between experienced and non-experienced males in articles 1 and 2. In article 3, behavioral pattern of males was influence by previous caretaking experience. Experienced males recovered quicker and carried the infants more than the inexperienced ones. However, inexperienced males showed a decrease in recovery latency and an increase in carrying time after successive exposure to infants. Cortisol levels changed after exposure to infant s vocalization, especially for experienced adult males. Male hormonal profile was not affected by the sight of infants neither by their previous experienced in caretaking. The occurrence of social interaction between the caretaker and infant did not modify the hormonal profile of common marmoset males; however, as much as experienced males carried the infants their cortisol levels decreased. Thus, members of a social group or potential caretakers common marmosets exposed to sensory cues from dependent infant such as vocalization, sight, smell and physical contact, changed their behavioral and hormonal responses that are physiological modulators of parental behavior in common marmoset
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A major difficulty to achieve maximum weight savings in the manufacture of composite structural components, is the tendency of these materials have the formation of voids and cracks in the interior and surface components. In aeronautical applications, controlling the volume fraction of fibers, resins and empty the components of composite is very hard. In this work, composites of epoxy matrix RTM6 reinforced with NCF (non crimp fabric carbon) processed by resin transfer molding (RTM) were characterized for porosity (P-ap) and density (rho(ad)). We used a method based on Archimedes' principle (ASTM C830) and the technique of helium pycnometer. The porosity values were compared with those determined by acid digestion (ASTM D3171). The mechanical properties of processed composites was evaluated by testing on the performing flexural and the results were correlated with the porosity value. All techniques tested to determine void content are satisfactory. The differents results can be justified for heterogeneous void distribution on laminate and differences among techniques characteristics. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of ICM11
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Low-density polyethylene (LDPE) was characterised for its dielectric and electrical properties before and after chemical treatment. A reduction in the permittivity and dielectric loss was observed in the polymer after treatment with hexane. The intensity in the Raman Spectrum in the disordered longitudinal acoustic mode region (DLAM) also was reduced due to a hexane treatment. Using thermally stimulated discharge current (TSDC) and laser-intensity-modulated method (LIMM) techniques it was observed that charge injection can be enhanced in the polymer matrix in the empty sites, created by the removal of the low molecular weight impurities with chemical treatment. (C) 2002 Kluwer Academic Publishers.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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One of the main applications of methane is in the production of syngas, a mixture of hydrogen and carbon monoxide. Procedures used in this process are steam reforming, CO2 reforming, partial oxidation and autothermal reforming. The present study evaluated and compared the behavior of nickel catalysts supported on mixed oxides of cerium and manganese in the partial oxidation of methane with that of nickel catalysts supported on mixed oxides of cerium and zirconium. Mixed oxides of cerium and zirconium or cerium and manganese were synthesized using two different preparation methods, the polymeric precursor based on Pechini method and combustion reaction using a microwave. This was followed by impregnation with nickel content of 15 %. Samples were calcined at 300, 800 and 900 °C and characterized by specific surface area (SSA), X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), temperature programmed reduction (TPR) and the reaction of partial oxidation of methane. The specific areas of samples decrease with the rise in calcination temperature and after nickel impregnation. Metal-cerium solid solution was formed and the presence of other manganese species outside the solid solution structure was confirmed in the compound with the highest amounts of manganese oxides showed. With regard to scanning electron microscopy, supports based on cerium and zirconium prepared by Pechini method exhibited agglomerated particles without uniform geometry or visible pores on the surface. However, compounds containing manganese presented empty spaces in its structure. Through synthesis by combustion reaction, morphology acquired independently of the proposed composition demonstrated greater porosity in relation to Pechini synthesis. Although catalysts were prepared using different synthesis methods, the insertion of nickel showed very similar reduction profiles (TPR). In relation to nickel catalysts supported on mixed oxide of cerium and zirconium, there is an initial reduction of NiO species that present certain interaction with the support. This is followed by the reduction of Ce4+ in Ce3+ surface, with subsequent bulk reduction. For catalysts containing manganese, a reduction of nickel oxide species occurs, followed by two stages of reduction for species Mn2O3 in Mn3O4 and Mn3O4 in MnO, with subsequent reduction of bulk. With respect to partial oxidation reactions, the nickel catalyst supported on mixed oxide of cerium and zirconium, prepared using the Pechini method, exhibited CH4 conversion of approximately 80 %, with conversion of 81 % when prepared by combustion. This behavior continued for 10 hours of reaction. Manganese content was also found to directly influence catalytic activity of materials; the greater the manganese oxide content, the faster deactivation and destabilization occurred in the catalyst. In both synthesis methods, the nickel catalyst supported on mixed oxide of cerium and zirconium maintained an H2/CO ratio very close to 2 during the 10 hours of partial oxidation reaction. Samples containing manganese displayed smaller H2/CO ratios and lower performance in partial oxidation.
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This paper has as its main focus the relation between the infringement act and the adolescents families social economical problematic, who obey the social educational deprivation of freedom at CEDUC in the district of Pitimbu RN, establishing in the theme Children and Adolescents, with the objective of showing how these families breed in the social economical and cultural political aspect. It also seizes who those adolescents are and their family members in their social aspect and as those families face their daily activities. The focus on the social matter, family, adolescent, infringement act, exclusion, inclusion formed the analysis categories which made myths and reality possible, taking into consideration the infringement act in our society. The data collection showed that those families conditions of life are of poverty. Families originated from low social classes, 62.5 % coming from the countryside and living with a daily income ranging from R$ 0,31 to R$ 8,31. Their level of education is low; there is lack of human and citizenship rights and no professional qualification whatsoever. It questions the degrading social exclusion suffered by millions of Brazilian people due to social, political and infringement economical problems. Has this favored the infringement practice? How to confirm the families lack of competence having the social vulnerability? Are the Public Political Institutions really performing the way they should? Are they really carrying out their role as they should? We have noticed that from then on, the necessity of understanding the exclusion/inclusion suffered not only in an imprecise and empty way, but understood as processes of integrative exclusion or ways of delinquency, where the excluding is not only the only one who has lack of material care but the one who is seen or recognized as a person, is not being treated as one. The effort of this paper provided an approach to our object, and the seizing of a close relation between the infringement act and the exclusion process or inclusion suffered, which are submitted to families of those adolescents who deprive of freedom
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For many decades the problematic raised about the indiscriminate use of pesticides in modern agriculture has incited the interest of many researchers to discover the effects caused by such products in the environment and consequently in the life of the ones which use that products (farmers) and those people who live in places next to the agricultural areas. Facing these facts, this research had the intention of comprehend the environmental perception of habitants of the Distrito Irrigado do Baixo-Açu (DIBA), located in the semiarid of Rio Grande do Norte, by using agro toxics and its possible environmental effects, as well as evaluate the levels of toxicity of waters from agricultural runoff in this region by using eco-toxicological exams with Ceriodaphnia silvestii. Were done 86 interviews with dwellers and farmers from DIBA. With the results reached in the evaluation of the interviews it was possible to identify that one of major problems is the inappropriate discard of empty packs of the pesticides used at that place. The samples collected for eco-toxicological evaluation showed a variation in its toxicity, once that the point of collect which receives waters from different cultures presented in four out of five samples toxicity for the tested species. Therefore, it concludes that the indiscriminate use of pesticides agricultural practice presented a potential to pollute to the irrigation waters, and the absence of elucidation by the farmers about the manipulation of these products contribute to the risk of environmental contamination and the possible decrease of the quality of life of the dwellers of the region
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Os condromas intracranianos são raros, sendo mais comumente encontrados na base do crânio e na região esfenoetmoidal. Nesta localização podem ser confundidos com meningiomas, neurinomas e craniofaringiomas. Os autores apresentam a evolução clínica e as características pela imagem de um paciente portador de condroma da sela turca submetido a excisão tumoral.