414 resultados para seletividade


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Some microorganisms from virgin ecosystems are able to use petroleum it as source of carbon and energy. The knowledge of microbial biodiversity can help to reveal new metabolic systems for utilization alkanes with biotechnological importance. The aim of this study is: i) Accomplish an in silico study of the AlkB protein aimed to understand the probable mechanism involved on selectivity of alkanes in Gram positive and Gram negative bactéria. ii) prospect and analyze the response of the microbial alkanotrophics communities in soil and mangrove sediments of BPP RN and soil of Atlantic forest in the Horto Dois Irmãos Reserve area/PE using the molecular biomarker, gene alkB; with the PCR and PCR-DGGE approach

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The ability to predict future rewards or threats is crucial for survival. Recent studies have addressed future event prediction by the hippocampus. Hippocampal neurons exhibit robust selectivity for spatial location. Thus, the activity of hippocampal neurons represents a cognitive map of space during navigation as well as during planning and recall. Spatial selectivity allows the hippocampus to be involved in the formation of spatial and episodic memories, including the sequential ordering of events. On the other hand, the discovery of reverberatory activity in multiple forebrain areas during slow wave and REM sleep underscored the role of sleep on the consolidation of recently acquired memory traces. To this date, there are no studies addressing whether neuronal activity in the hippocampus during sleep can predict regular environmental shifts. The aim of the present study was to investigate the activity of neuronal populations in the hippocampus during sleep sessions intercalated by spatial exploration periods, in which the location of reward changed in a predictable way. To this end, we performed the chronic implantation of 32-channel multielectrode arrays in the CA1 regions of the hippocampus in three male rats of the Wistar strain. In order to activate different neuronal subgroups at each cycle of the task, we exposed the animals to four spatial exploration sessions in a 4-arm elevated maze in which reward was delivered in a single arm per session. Reward location changed regularly at every session in a clockwise manner, traversing all the arms at the end of the daily recordings. Animals were recorded from 2-12 consecutive days. During spatial exploration of the 4-arm elevated maze, 67,5% of the recorded neurons showed firing rate differences across the maze arms. Furthermore, an average of 42% of the neurons showed increased correlation (R>0.3) between neuronal pairs in each arm. This allowed us to sort representative neuronal subgroups for each maze arm, and to analyze the activity of these subgroups across sleep sessions. We found that neuronal subgroups sorted by firing rate differences during spatial exploration sustained these differences across sleep sessions. This was not the case with neuronal subgroups sorted according to synchrony (correlation). In addition, the correlation levels between sleep sessions and waking patterns sampled in each arm were larger for the entire population of neurons than for the rate or synchrony subgroups. Neuronal activity during sleep of the entire neuronal population or subgroups did not show different correlations among the four arm mazes. On the other hand, we verified that neuronal activity during pre-exploration sleep sessions was significantly more similar to the activity patterns of the target arm than neuronal activity during pre-exploration sleep sessions. In other words, neuronal activity during sleep that precedes the task reflects more strongly the location of reward than neuronal activity during sleep that follows the task. Our results suggest that neuronal activity during sleep can predict regular environmental changes

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Due to environmental restrictions around the world, clean catalytic technology are of fundamental importance in the petrochemical industry and refineries. Creating the face of this a great interest in replacing the liquid acids for solid acids, so as molecular sieves have been extensively studied in reactions involving the acid catalysis to produce chemical substances with a high potential of quality. Being the activity of the catalysts involved in the reaction attributed to the acid character of them involved for the Lewis and Brönsted acid sites. Based on this context, this study aimed to prepare catalysts acids using a molecular sieve silicoalumino-phosphate (SAPO-11) synthesized in hidrotermical conditions and sulphated with sulphuric acid at different concentrations, using to it the method of controlled impregnating. The samples resulting from this process were characterized by x-ray difratometry (DRX), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), thermal analysis (TG-DTG) and determination of total acidity (by n-butilamin adsorption). The results show that the synthesis method used was efficient in the formation of AEL structure of SAPO-11 and when being incorporated the sulfate groups in this structure the acidity of the material was increased, pointing out that to very high concentrations of acid there is a trend of decrease the main peaks that form the structure. Finally they were tested catalytictly by the reaction model of conversion of m-xylene which showed favorable results of conversion for this catalyst, showing to be more selective of cracking products than isomerization, as expected, in order that for the o-xylene selectivity there was no positive change when to sulfate a sample of SAPO-11, while for light gases of C1-C4 this selectivity was remarkably observed

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In order to obtain a biofuel similar to mineral diesel, lanthanum-incorporated SBA- 15 nanostructured materials, LaSBA-15(pH), with different Si/La molar ratios (75, 50, 25), were synthesized in a two-steps hydrothermal procedure, with pH-adjusting of the synthesis gel at 6, and were used like catalytic solids in the buriti oil thermal catalytic cracking. These solids were characterized by X-ray fluorescence (XRF), powder X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG), infrared spectroscopy (FTIR), nitrogen porosimetry and ethanol dehydration, aiming to active sites identify. Taken together, the analyses indicated that the synthesis method has employed to obtain materials highly ordered mesostructures with large average pore sizes and high surface area, besides suggested that the lanthanum was incorporated in the SBA-15 both into the framework as well as within the mesopores. Catalytic dehydration of ethanol over the LaSBA-15(pH) products has shown that they have weak Lewis acid and basic functionalities, indicative of the presence of lanthanum oxide in these samples, especially on the La75SBA-15(pH) sample, which has presented the highest selectivity to ethylene. The buriti oil thermal and thermal catalytic cracking, realized from the room temperature to 450 ºC in a simple distillation system, has allowed obtaining two liquid fractions, each consisting of two phases, one aqueous and another organic, organic liquid (OL). The OL obtained from first fractions has shown high acid index, even in the thermal catalytic process. One the other hand, OL coming from second ones, called green diesel (GD), have presented low acid index, particularly that one obtained from the thermal catalytic process realized over LaSBA-15(pH) samples. The acid sites presence in these samples, associated to their large average pore sizes and high surface areas, have allowed them, especially the La75SBA-15(pH), to present deoxygenating activity in the buriti oil thermal catalytic cracking, providing an oxygenates content reduction, particularly carboxylic acids, in the GD. Furthermore, the GD comes from the second liquid fraction obtained in the buriti oil thermal catalytic cracking over this latest solid sample has shown hydrocarbons composition and physic-chemical properties similar to that mineral diesel, beyond sulfur content low

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Catalytic processes are widely present in everyday life. This results in large number of studies seeking materials that may combine the low cost catalytic efficiency. Based on this assumption, the clays have long been used as catalysts, with its huge availability, diversity and possibility of improving their properties from structural changes, primarily responsible for this great use. Among the natural clays, vermiculite due to their characteristic properties (high cation exchange capacity and expansion), is suitable for various applications including as catalysts and catalyst supports. In this work, the acid leaching of clay vermiculite was performed, coming from Santa Luzia-PB, with nitric acid (2, 3 and 4 mol / L) and subsequent calcination of the materials obtained. The materials were named as Vx/400, where x is the acid concentration employed and 400 used in calcination temperature. The effectiveness of changes made was determined by XRD techniques, FT-IR, EDS, TG/DTG, nitrogen physisorption and DTP of n-butylamine. Acid leaching has improved some properties of the clay - specific area and acidity - but the control of the acid concentration used is of vital importance, since the highest concentration caused the partial destruction of vermiculite entailing a decline in their properties. For analysis of the catalytic activity of the modified clay was made a comparative study with the SBA -15 mesoporous materials, synthesized via hydrothermal method, using the pyrolysis of low density polyethylene (LDPE). The results showed that the acid plays a fundamental role in the conversion of the polymer into smaller molecules, the material V3/400 was more selective for the source monomer (ethylene) due to their increased acidity, which promotes more breaks bonds in the polymeric chain, while materials and V0/400 V2/400, lower acidity, showed higher selectivity to light hydrocarbons, the range of fuel (41.96 and 41.23%, respectively), due to less breakage and secondary condensation reactions chains; already V4/400 SBA-15/550 and resulted in lower percentages of light hydrocarbons and the partial destruction of the structure and low acidity, respectively, responsible for the inefficiency of materials

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Bifunctional catalysts based on zircon oxide modified by tungsten (W = 10, 15 and 20 %) and by molybdenum oxide (Mo= 10, 15 e 20 %) containg platinum (Pt = 1%) were prepared by the polymeric precursor method. For comparison, catalysts the tungsten base was also prepared by the impregnation method. After calcinations at 600, 700 and 800 ºC, the catalysts were characterized by X-ray diffraction, fourier-transform infrared spectroscopy, thermogravimetric and differential thermal analysis, nitrogen adsorption and scanning electron microscopy. The profile of metals reduction was determined by temperature programmed reduction. The synthesized catalysts were tested in n-heptane isomerization. X-ray diffractogram of the Pt/WOx-ZrO2 and Pt/MoOx-ZrO2 catalysts revealed the presence of tetragonal ZrO2 and platinum metallic phases in all calcined samples. Diffraction peaks due WO3 and ZrO2 monoclinic also were observed in some samples of the Pt/WOx-ZrO2 catalysts. In the Pt/MoOx-ZrO2 catalysts also were observed diffraction peaks due ZrO2 monoclinic and Zr(MoO4)2 oxide. These phases contained on Pt/WOx-ZrO2 and Pt/MoOx-ZrO2 catalysts varied in accordance with the W or Mo loading and in accordance with the calcination temperature. The infrared spectra showed absorption bands due O-W-O and W=O bonds in the Pt/WOx-ZrO2 catalysts and due O-Mo-O, Mo=O and Mo-O bonds in the Pt/MoOx-ZrO2 catalysts. Specific surface area for Pt/WOx-ZrO2 catalysts varied from 30-160 m2 g-1 and for the Pt/MoOx-ZrO2 catalysts varied from 10-120 m2 g-1. The metals loading (W or Mo) and the calcination temperature influence directly in the specific surface area of the samples. The reduction profile of Pt/WOx-ZrO2 catalysts showed two peaks at lower temperatures, which are attributed to platinum reduction. The reduction of WOx species was evidenced by two reduction peak at high temperatures. In the case of Pt/MoOx-ZrO2 catalysts, the reduction profile showed three reduction events, which are attributed to reduction of MoOx species deposited on the support and in some samples one of the peak is related to the reduction of Zr(MoO4)2 oxide. Pt/WOx-ZrO2 catalysts were active in the n-heptane isomerization with high selectivity to 3-methyl-hexane, 2,3- dimethyl-pentane, 2-methyl-hexane among other branched hydrocarbons. The Pt/MoOx-ZrO2 catalysts practically didn't present activity for the n-heptane isomerization, generating mainly products originating from the catalytic cracking

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This work was developed in the extent of the Post Graduation Program in Social Service of the Federal University of Rio Grande do Norte. It talks about the process of inclusion of the disabled people in the Job market in Mossoró-RN, bringing for the academic debate relevant thematic for the Brazilian society, for the profession of Social Service and similar areas and for the people with deficiency. It has the objective to apprehend the determiners that make possible the process of the disabled people's inclusion in the Job market in Mossoró, having as parameter the National Politics for the Integration of People Bearers of Deficiency. The critical theoretical perspective is backed in Marx's ideas for the understanding concerning the work, as well as in Pochamann, concerning the job market, regarding the exclusion/inclusion category is based in Martins, Yasbek and Sposati and on deficiency in the National Politics for the Integration of the Disabled People. The research is of qualitative nature and it took as subjects 26 (twenty-six) people, being 09 (nine) people with deficiency, inserted in the formal job and regulated market, and 17 (seventeen) managers of private companies and public institutions of the city of Mossoró-RN. For the collection of data we used techniques of nonsystemic observation, semi-structured interview and documental analysis. The results of the research mark that any modality of the human workforce used in the current context, they are functional to the capitalism and they move forward towards exploration, alienation and subordination of the work to the capital; the National Politics for the Integration of the People with Deficiency expresses and reproduces the contradictory dynamics of the class society, it reflects the neo liberal shades through the selectivity and of the articulation among the federated beings and organizations of the civil society for its operational system; there is a misproportion between the percentages of the quotas and the amount of people with deficiency inserted in the job market, just corresponding to a tiny numeric magnitude; the developed activities are of low social status and it is expressive the amount of workers that receives between one and two minimum wages. These data drive us to infer that the mentioned politics make possible, partly, the inclusion of the disabled people in the job market, though, such inclusion is executed in the selective or focused dimensions, marginal, precarious and unstable

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This paper proposes discusses the theme of the youth and of the violation of rights in the context of the Young Agent Program developed in the local authority of Arez/RN, sugar cane region of the Brazilian northeast. We take like empirical reference, the young people in the age group from 15 to 17 years old that were participating of the activities of the Program, in the period of April to July of 2008. Objectives of this study were constituted, economical-partner apprehended the conditions and cultural of the young participants of the Young Agent Program, in the context of violations of rights; as well as the analysis of the limits and means, of the bases theoretician-politician, methodological and of the activities developed in the Program. In the persecution of the objectives we use like methodological instrumental the observation, activities in group with the focal group technique and the application of semi-structured interviews. As result, we notice that the violation of rights of the young persons inserted in the Young Agent Program of Arez sets itself up as reflex of the multiple determinations of the social question, inherent in the capitalist society, specified in the context of the poverty and of the social unequality that they acquire visibility in the hunger, in the unemployment / menial job, in the precarious dwelling, in the low schooling, for lack of leisure, in the violence between others. The approximations systematized in this healthy work relevant for the Unveiling of the reality of the Brazilian youth, specifically of Arez young people, in such a way that they come to subsidize future inquiries, are eaten by me also it promotes the discussion around the way like the Social Politics Programs they are implemented and driven in the capitalist society, in its neoliberal format, where the focusing and the selectivity is put on top to the detriment of the universal access of the democratic rights. So, the great challenge that is put for the XXI century is to cause to the voices from these which they do and this which build this country, in the continuous and tireless search of the rights realization in the struggle against the barbarism installed in the capitalist societycapitalista

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The study is about the non-insertion of the Social Assistant in the work market of Natal/RN, emphasizing the perception those Social Assistants have about this problem. We try to analyze the relation that those workers figure out about their non-insertion in the work market and their professional formation. The problem is related to the present unemployment rates in our society, which results of the changes that have affected the world of work as a whole in the wake of the Productive Restructuring and State Reformation supported by the neo-liberalism ideological system. We realize that these factors have deeply affected the configurations of the work market in general; especially those related to professions whose challenges multiply obstacles not only to the insertion of new workers, but to their staying in their job. We note that the reality of the work market has been built up on the decrease of the work force opportunities and the increase of the selectivity criteria to insertion of new workers. In consequence, unemployment rates increase everywhere, regardless of place, profession or education level of the workers. Work and management changes have brought about new challenges to professional formation. The presence of neo-liberalism productive and market logic demands a more adequate professional formation to work market from their candidates to a job. Due to the numberless difficulties workers face nowadays to enter the world of work, society itself and workers in general begin to question the profession of their choice, the kind of formation they have got, and frequently they lay the blame of their professional difficulties on it. This result has come out from the research we did with some social assistants not inserted in the professional work market in Natal/RN. The research reveals too that those unemployed professionals see their difficulties connected to their professional formation and they happen to say that the main challenge they face today is to get acknowledgment to the significance and importance of their profession

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This research comprises a study about the social assessment performed by the Social Worker in the review process of the Benefit of Continued Installment. The Benefit of Continued Installment was implemented in 1996 and guarantees a minimum salary to the deficiency person and to an elder with sixty five years or more and that proves not to have ways to support neither himself/herself nor his/her own family. It is a demand to include in the BPC that the maximum income of a family does not exceed ¼ of minimum salary and that every two years this benefit to be revised to evaluate its continuity based in its original conditions. This study was carried out in the municipality of Natal/RN, with thirteen social workers, being the collection of data performed through interviews and social assessments of the users that count with the benefit. The results show that the users selected by the criterion of the income, present a profile of poverty and deprivations demonstrated through several situations survived in its daily life, indicative of vulnerability. It was demonstrated that the Social workers has relative autonomy in the evaluations along with the users and that it denotes the necessity of inclusion. However, by following the imposed criteria, it corroborates with the logic of exclusion. So, it is identified in the Municipality of Natal/RN, following the orientation given the politics of social work at national level, the implementation of revision of the BPC, for the social workers, from rigorous processes of selection and exclusions

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JUSTIFICATIVA E OBJETIVOS: Os fármacos alfa2-agonistas são a cada dia mais utilizados em Anestesiologia, seja como adjuvantes ou como agentes anestésicos únicos. Atualmente, o emprego da dexmedetomidina vem se popularizando devido à sua maior seletividade aos receptores alfa2 e, também, ao seu perfil farmacocinético. O objetivo desta revisão foi fazer uma análise do emprego da dexmedetomidina em neurocirurgia. CONTEÚDO: Além das considerações e revisão da literatura quanto ao emprego da dexmedetomidina especificamente em procedimentos neurocirúrgicos, foi realizada descrição dos efeitos do fármaco nos diversos sistemas do organismo. CONCLUSÕES: A dexmedetomidina tem perfil farmacocinético e farmacodinâmico que favorece seu emprego em diversos procedimentos neurocirúrgicos. A utilização clínica em procedimentos cirúrgicos com craniotomia para pinçamento de aneurisma e remoção de tumores é crescente. Além disso, seu uso em intervenções cirúrgicas funcionais é promissor.

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Nowadays we can observe in Natal city, the development of the structure and the health s private service. However, the spatial distribution of these services will be marked by an uneven distribution on the places, what will be in according with the conditions offered by the same in each historical period. Accordingly, the objective of this job is analyze the use of the territory by the health s private service and the dynamics that promotes in Natal city in the technical scientific information period. Thus, seeking to search this goal, realized literature, documentary, empirical, considering the process of development and the spatial distribution of the health s private service in the city. From a topology we can observe that prevails in the city a service s concentration at all levels of complexity in only a few neighborhoods, being Tirol and Petrópolis, which are neighborhoods that have high densities of engineer system, bigger fluidity, and the best level salaries of the city, which present a greater number of these establishments. However, equal this concentration has occurred a dispersion of these services to other neighborhoods, as for example Lagoa Nova which is presenting the same attractiveness in the view of attributes territorial, begins to protect services presenting the same profile like the firsts. However, the city has a significant demand to this kind of service found in these neighborhoods, some events provided the emergency of another type of market of health s private service, that are those created to attend guests with a lower purchasing power, which will have their establishments in the same way selectively distributed in some areas of the city, which will not be the same pursued by the other, showing how selective is the installation of an enterprise guide by the logic of capitalism reproduction. So, the imperative of spatial selectivity presented by the health s private sector exposes an use of the differential territory for these services

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Este artigo aborda a compreensão da avaliação no interior da implantação do Regime de Progressão Continuada no Estado de São Paulo. Ao penetrar nos intrincados caminhos da realidade escolar, por meio da pesquisa qualitativa, acompanharam-se sistematicamente durante um ano escolar 4 turmas de alunos (uma de cada ano do ciclo I, ainda do Ensino Fundamental de 8 anos), nos momentos coletivos da escola: horário de trabalho pedagógico coletivo, reuniões de pais e mestres, conselhos de classe/série, eventos; e, ainda, realizaram-se entrevistas com 7 profissionais envolvidos com as turmas (5 professores, coordenadora pedagógica e diretora escolar) e com 124 alunos. Observou-se que a avaliação informal ganha forte expressão nessa nova forma de organização escolar, revelando, também, novas formas de manutenção da seletividade e da exclusão escolar. Por meio da análise das práticas avaliativas e das contribuições dos diversos atores da escola, evidencia-se a presença da seletividade escolar, mas com configuração diferenciada: a exclusão branda e/ou a eliminação adiada.