943 resultados para Radiação fotossinteticamente ativa


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Esta pesquisa apresenta os resultados do estudo sobre a prática pedagógica em uma classe multisseriada do programa escola ativa. A mesma tem como objetivo identificar a existência de práticas pedagógicas inovadoras na sala de aula do referido programa. Trata-se de um estudo de caso etnográfico, de abordagem qualitativa, o qual nos possibilitou a análise da realidade concreta, por meio da análise da documentação, observação do cotidiano da sala de aula e entrevistas. As relações que ocorreram no âmbito da escola, a análise dos fatos ocorridos e do discurso dos sujeitos se constituiu de grande importância para esta pesquisa. O campo de observação da pesquisa e coleta dos dados aconteceu na Escola Municipal Ernesto Geisel na Agrovila da Barragem no município de Lagoa do Carro, em Pernambuco. Participaram deste estudo, uma classe multisseriada do programa escola ativa composta por dezessete estudantes e uma professora. As aulas aconteciam à tarde. Os alunos cursavam o 4º e 5º ano do ensino fundamental da educação básica. Utilizaram-se, como procedimentos para coleta dos dados para o registro da prática pedagógica, relatórios e anotações em diários. Por se constituir uma pesquisa de natureza qualitativa, no decorrer do trabalho de campo, foi possível e necessária à flexibilização, alterações e ajustes (no decorrer do processo), haja vista a necessidade de alcançar os objetivos pretendidos. O estudo sinalizou para a necessidade de novas reflexões sobre a inovação nas práticas pedagógicas do programa escola ativa e educação do campo, pois se concluiu que, diferentemente daquilo que é descrito nos documentos oficiais, ela não está ocorrendo na prática, sendo necessária a ruptura com o sistema arcaico e tradicional de ensino e aprendizagem.

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Fucan is a term used to denominate L-fucose rich sulfated polysaccharides. The fucans have been studied due their pharmacological activities like antithrombotic, antiproliferative and antioxidant. We have extracted three fucan fractions from the brown seaweed Spatoglossum schröederi. These fucans were denominated Fuc B 1, Fuc B 1.5 and Fuc B 2. The chemical analyzes show that the fucans have very similar composition as demonstrated by agarose electrophoresis gel, sugar and sulfate content. The antiproliferative effect was determined by MTT and BrdU methodologies in CHO cells. The inhibition of proliferation effect of the three fractions was about 40%. Therefore this we proceed just with the Fuc B 2 due the higher yield. There is no apoptosis indication using the anexin V/propidium iodide test. We found a cell cycle phase G1 arrest. The western blotting show that the PKC; pFAK; pERK 1/2 are activated when the cells were treated with fucans. The treatement with inhibitor of MAPK PD98059 extinguished the fucan effect. These results indicates that fucan act by the ERK pathway inducing the cell death.

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This work main objective is to study the use of bricks in barium X-rays rooms in order to contribute to the optimization of shielding rooms diagnosis. The work was based on experimental measurements of X-ray attenuation (40 to 150 kV), using ceramic seal bearing the incorporation of barium sulfat (BaSO4). Different formulations were studied in three different firing temperatures and evaluated for incorporation in the ceramic body. The composition of 20% of barite processed at a temperature of 950 ° C showed better physical and mechanical properties, is considered the most suitable for the purpose of this work. Were produced bricks sealing composition formulated based on that presented the best technological features. These blocks were tested physically as a building material and wall protective barrier. Properties such as visual, deviation from the square, face flatness, water absorption and compressive strength were evaluated for all the blocks produced. The behavior of this material as attenuator for X-rays was investigated by experimental results which take into account mortar manufacturers barium through the different strains and compared with the reference material (Pb). The simulation results indicated that the ceramic block barium shows excellent properties of attenuation equivalence lead taking into account the energy used in diagnostic X-ray

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The addition of active silica potentially improves the quality of concrete due to its high reactivity and pore refinement effect. The reactivity of silica is likely related to its charge density. Variations in surface charge alter the reactivity of the material consequently affecting the properties of concrete. The present study aimed at investigating variations in the charge density of silica as a function of acid treatments using nitric or phosphoric acid and different pH values (2.0, 4.0 and 6.0). Effects on concrete properties including slump, mechanical strength, permeability and chloride corrosion were evaluated. To that end, a statistical analysis was carried out and empirical models that correlate studied parameters (pH, acid and cement) with concrete properties were established. The quality of the models was tested by variance analysis. The results revealed that the addition of silica was efficiency in improving the properties of concrete, especially the electrochemical parameters. The addition of silica treated using nitric acid at pH = 4.0 displayed the best cement performance including highest strength, reduced permeability and lowest corrosion current

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The increase in ultraviolet radiation (UV) at surface, the high incidence of non-melanoma skin cancer (NMSC) in coast of Northeast of Brazil (NEB) and reduction of total ozone were the motivation for the present study. The overall objective was to identify and understand the variability of UV or Index Ultraviolet Radiation (UV Index) in the capitals of the east coast of the NEB and adjust stochastic models to time series of UV index aiming make predictions (interpolations) and forecasts / projections (extrapolations) followed by trend analysis. The methodology consisted of applying multivariate analysis (principal component analysis and cluster analysis), Predictive Mean Matching method for filling gaps in the data, autoregressive distributed lag (ADL) and Mann-Kendal. The modeling via the ADL consisted of parameter estimation, diagnostics, residuals analysis and evaluation of the quality of the predictions and forecasts via mean squared error and Pearson correlation coefficient. The research results indicated that the annual variability of UV in the capital of Rio Grande do Norte (Natal) has a feature in the months of September and October that consisting of a stabilization / reduction of UV index because of the greater annual concentration total ozone. The increased amount of aerosol during this period contributes in lesser intensity for this event. The increased amount of aerosol during this period contributes in lesser intensity for this event. The application of cluster analysis on the east coast of the NEB showed that this event also occurs in the capitals of Paraiba (João Pessoa) and Pernambuco (Recife). Extreme events of UV in NEB were analyzed from the city of Natal and were associated with absence of cloud cover and levels below the annual average of total ozone and did not occurring in the entire region because of the uneven spatial distribution of these variables. The ADL (4, 1) model, adjusted with data of the UV index and total ozone to period 2001-2012 made a the projection / extrapolation for the next 30 years (2013-2043) indicating in end of that period an increase to the UV index of one unit (approximately), case total ozone maintain the downward trend observed in study period

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This study was aim to evaluate the effectiveness of strategies non pharmacological for the relief of the intensity of the parturient pain in the phase activates of the dilation period in the labor. Is a clinic rehearse of the type therapeutic intervention before and after" with a quantitative approach, accomplished in the Humanized Unit of Childbirth of the Maternity Januário Cicco School of the Federal University of Rio Grande do Norte, in Natal/RN, whit 130 parturient, being 30 in the pre-test of the strategies and 100 in the application of the strategies non pharmacological combined (breathing exercises, muscular relaxation and lombossacral massage) and isolated (shower bath in a normal temperature). We used the visual analogical scale to evaluate the intensity of the pain of the study parturient before and after" to the application of the strategies in the phases of acceleration, maximum inclination and desaceleration in the phase activates of dilation period in the labor. The principal results showed that the majority of the study parturient was between 20 to 30 years old (60%); with incomplete fundamental teaching (85%); family income until 2 minimum wages (74%); 78% had a companion and these, 44% were the own husband. The oxytocin was administered in the parturient during the phase activates of the labor in 81% of the cases and only 15% these women didn´t reciev anything medication. We verified significant relief (ρ=0.000) of intensity of the pain of the study parturient after application of the strategies non pharmacological combined and isolated. We concluded that the strategies non pharmacological combined and isolated were effective in the relief of the pain of the study parturient in the phase activates de labor

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The active modified atmosphere effect was evaluated in the quality of squash fresh-cut (MP).. The squash pieces were conditioned in plastic packings and submitted the gases application in the following concentrations: 0.03% CO2 and 21% O-2 (controls T1); 5% CO2 and 4% O-2 (T2); 6% CO2 and 4% O-2 (T3); 7% CO2 and 4% O-2 (T4); 8% CO2 and 4% O-2 (T5). In T6 it was made vacuum application in the packing. The packings containing the squash were stored in to the temperature of 10 degrees C and relative humidity of 75% for 12 days. The evaluated analyses were weigth loss, total acidity (AT), pH, soluble solids (SS), ratio, firmness, color, antioxidant activity for DPPH and carotenoids content. The weigth loss was gradual and low until the ninth day of storage. The values of AT increased along the experimental period being superior for T1 and T2. The increase of SS during the storage of the fresh-cut squash went smaller for T3 and T4. The brightness stayed during the storage being superior for T5, already the color components red and yellow decreased along the experimental period.

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A transmissão de radiação ultravioleta de comprimentos de onda entre 250 e 360 nm através do pelame e da epiderme de bovinos foi determinada em laboratório, usando-se amostras de couro de animais recém-abatidos. A quantidade de radiação transmitida através do pelame depende da coloração e também das características estruturais do pelame (espessura da capa; comprimento, diâmetro, número e inclinação dos pêlos), pelas quais é definido o trajeto médio de um fóton pela massa de pêlos (L). A maior transmissão é proporcionada por pelames brancos com altos valores de L, ao passo que pelames negros em geral apresentam transmissão nula ou muito baixa. Quanto menos pigmentada a epiderme, maior a transmissão de radiação através da sua superfície. A melhor proteção é proporcionada por pelames negros com baixo valor de L sobre epiderme igualmente negra, mas em vista do aquecimento causado pela absorção de radiação térmica (em vacas Holandesas a temperatura das malhas negras atinge 44,1ºC ao mesmo tempo em que a das malhas brancas é 37,7ºC), a combinação ideal para ambientes tropicais é um pelame branco com baixo valor de L sobre epiderme negra, uma combinação dificilmente encontrada em animais de raças européias. Uma alternativa seria um pelame negro com um baixo valor de L. Animais vermelhos apresentam alta transmissão de radiação UV através da epiderme e do pelame, sendo desaconselhados para ambientes tropicais. Entretanto, foi observada uma vaca Holandesa com áreas isoladas de epiderme negra coberta com pelame branco, o que pode trazer perspectivas para uma seleção para combinações mais adequadas de epiderme e pelame em bovinos de raças européias.

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This work aims at developing an evaluation of the implementation of the Program Escola Ativa as a public policy for rural schools with combined grade classrooms in Jardim do Seridó RN (1998 2009) focusing on the following dimensions: school s physical environment, training, follow up, and didactic usage of the methodology. In order to develop this research we refer to the literature that analyzes the cycle of policies (FREY, 2000). In this approach, evaluation represents an important step in the process of analyzing the implementation of public policies, as a way of measuring up their performance, as well as a guide for realignments and redefinitions (PRESSMAN; WILDAVSKY, 1998). In order to accomplish this function, the evaluator of policies must be acquainted with scientific concepts and methods that consist of describing, interpreting and analyzing the policies in the governmental sphere (MENY; THOENIG, 1992; LIMA JÚNIOR, 1978). In this perspective, we intend to investigate whether in its proposition of minimizing the blanks in the Brazilian educational system, the implementation of the Program would be contributing to the improvement of the political-pedagogical practices in the rural schools with combined grade classrooms in Jardim do Seridó RN. In order to do this research, we have developed a theoretical-methodological matrix made of analysis dimensions, variables, indicators and instruments, such as literary revision, documental analysis, semi-structured interviews with four teachers and three supervisors that work and/or have worked in Escola Ativa in that town in the period comprised among 1998 2009, besides notes taken from field observation and photographs from four rural schools with combined grade classrooms. With this research we have identified that the Program, at a national level, has gone through different phases in its implementation process, for the town was not ready to fully take the responsibilities of the autonomous expansion, in 2002. From that period on, the execution of Escola Ativa has suffered several discontinuities, such as the lack of professional training and supervising. It is also noted that the methodology contributes to the dynamization of the didactic-pedagogical activities and promotes the cooperation and autonomy of the students in the organization and the applicability of the components of the curriculum, especially of Governo Estudantil and Cantinhos de Aprendizagem. Although the directions of the Program (BRASIL, 2005) point out that Escola Ativa has among its principles social transformation, we identified that, isolated, the initiative is not capable of promoting the changes that the rural schools need, namely investments in the physical, material, pedagogical and technological infra-structure, besides the estimation and a career plan for the teachers. In a general draft of the results of this research, we realized that some aspects presented about the peculiarities of Escola Ativa in Jardim do Seridó as a governmental Program, reinforce the need for the public policies to be evaluated, in order to confront critic and operationally the planning with the practice, revising action, whenever necessary

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The issue of multi-classes in schools from the field and methodology for these classes is controversial and contentious, both in terms of teaching, monitoring and organizational, is the perspective of values, training and systematization of public policy. Why the strategy Methodological Active School facing those classes appeared as a significant and exciting topic of research. Thus, it was aimed to apprehend the social representations of active school by teachers (s) to understand the extent to which these representations influence the acceptance and use of the program strategies. Perceiving and analyzing also the various factors related to the management, monitoring and training needs of (the) teachers as alternatives to make this meaningful action. The study focused 112 teachers (s), which for over a year, worked in the program in six municipalities in the micro-region of Rio Grande do Norte / RN - Areia Branca, Baraúna, Grossos, Mossoró, Serra do Mel and Tibau. From this perspective relied on Social Representation Theory and the Theory of the Central Core, attending to the subjectivity of the object searched, inserted in the psychosocial field of knowledge, we opted for multi-methodological approach, using quantitative and qualitative techniques. However, the highlight was a projective technique Free Association of Words from the term Active School is .... The words were systematized by EVOC program, and also applied semi-structured interviews, focusing specific issues that led to trace the socio-demographic profile of (the) participants and wider issues about the object of study. The evocations, justifications and interviews provided the basis for the analysis of the content that followed the steps: formation of the corpus, the composition of the analysis and categorization. The results show the representations an attitude of acceptance and positive appraisal of the participants to the Active School Program. At the core, these representations are objectified around the words "action", "learning", "autonomy" and "interaction". Based on the premise that the representations have a duty to guide the practices and behavior, one can see that the positive attitude of the group favors a systematic methodology and acceptance of the program, but we must look at the changes in management, training, monitoring of (the) teachers (s) and support to schools.

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É apresentado um método para a estimativa do balanço térmico por radiação em vacas da raça Holandesa expostas ao sol e sob a sombra em uma pastagem, com o objetivo de estabelecer um padrão morfológico mais adequado para esses animais em região tropical. O método envolve a determinação das características do pelame (área de superfície de malhas negras, espessura da capa, comprimento e diâmetro dos pêlos, número de pêlos por unidade de área), temperatura da superfície da capa e da epiderme e variáveis ambientais (irradiância solar, temperatura do ar e de globo, vento). Foi determinada a quantidade de radiação de ondas curtas efetivamente transmitida através do pelame e que atinge as camadas profundas da epiderme. Demonstrou-se, por intermédio de um exemplo prático, que as áreas de pelame negro apresentaram balanço radiante mais elevado que as áreas brancas, mas estas últimas possuiam maior transmissividade para a radiação de ondas curtas. Animais predominantemente negros foram melhor protegidos contra a radiação de ondas curtas que os predominantemente brancos, especialmente quando a capa de pelame é pouco espessa (até 4 a 7 mm), mais adequada para ambientes tropicais.

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O objetivo deste trabalho foi avaliar o efeito da irradiação gama associada à atmosfera modificada passiva na qualidade pós-colheita de goiabas 'Pedro Sato', verificando suas características físico-químicas. Foram utilizadas goiabas provenientes da região de Vista Alegre do Alto-SP,Brasil. Após a colheita, as goiabas foram imediatamente transportadas ao Laboratório de Frutas e Hortaliças, pertencente ao Departamento de Gestão e Tecnologia Agroindustrial, da Faculdade de Ciências Agronômicas - UNESP - Câmpus de Botucatu-SP, onde foram armazenadas a 10ºC e 90-95%UR, em câmara frigorífica, por 28 dias. Os tratamentos foram: controle 1 (sem embalagem e sem irradiação); controle 2 (embalagem de poliestireno (PS) + polietileno de baixa densidade (PEBD) e sem irradiação); tratamento 1 (PS+PEBD e 0,2kGy); tratamento 2 (PS+PEBD e 0,6kGy), e tratamento 3 (PS+PEBD e 1,0kGy). As análises realizadas foram: firmeza, sólidos solúveis (SS), acidez titulável (AT) e índice de maturação. Foi utilizado o delineamento inteiramente casualizado, com esquema fatorial 5 x 5 (tratamento x tempo). Concluiu-se que as altas doses de irradiação promoveram efeito negativo nas características físico-químicas da goiaba 'Pedro Sato', e que apenas a menor dose utilizada (0,2kGy) associada à atmosfera modificada conservou frutos com maior qualidade e aceitabilidade, indicado por maiores índice de maturação e teor de sólidos solúveis obtidos.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This work presents the development of a prototype of an intelligent active orthosis for lower limbs whit an electronic embedded system. The proposed orthosis is an orthopedical device with the main objective of providing walking capacity to people with partial or total loss of lower limbs movements. In order to design the kinematics, dynamics and the mechanical characteristics of the prototype, the biomechanics of the human body was analized. The orthosis was projected to reproduce some of the movements of the human gait as walking in straight forward, sit down, get up, arise and go down steps. The joints of the orthosis are controlled by DC motors equipped with mechanical reductions, whose purpose is to reduce rotational speed and increase the torque, thus generating smooth movements. The electronic embedded system is composed of two motor controller boards with two channels that communicate with a embedded PC, position sensors and limit switches. The gait movements of the orthosis will be controlled by high level commands from a human-machine interface. The embedded electronic system interprets the high level commands, generates the angular references for the joints of the orthosis, controls and drives the actuators in order to execute the desired movements of the user