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Growth inhibitory activities and feeding deterrence of solanaceae-based derivatives on fall armyworm
No full textSpodoptera frugiperda is a pest of worldwide importance, responsible for significant economic losses, mainly in maize crops. The use of botanical derivatives emerges as a promising alternative to control this insect pest. In this work, we evaluated the effect of ethanolic extracts (EE) and semi-purified fractions of Acnistus arborescens and Datura stramonium (Solanaceae) on the biological development of S. frugiperda and the effects of the semi-purified fractions on feeding behavior of 4th instar caterpillars. Crude extracts and fractions caused lethal and sublethal effects, namely increasing both duration of larval and pupal stages as well as deformities in adults, and decreasing weight of pupae. In turn, the effects on feeding deterrence were more pronounced in treatments with A. arborescens fractions. Our results highlight the potential of EE from solanaceous species as a source of allelochemicals that can be used in the integrated management of S. frugiperda
Water desorption monitoring of cellulose pulps by nir spectroscopy
No full textNear infrared (NIR) spectroscopy can be implemented in the evaluation of cellulose. The potential of NIR spectroscopy combined with multivariate analysis to evaluate moisture variation in pulp was studied. Samples of four pulp types were conditioned to different moisture levels. The samples were air dried in a controlled environment, at each 10 % moisture reduction the material was weighed and analyzed with the NIR spectrometer. Principal Component Analysis (PCA) and Partial Least Squares Regression (PLS-R) were applied to the spectral signatures and moisture values obtained during drying. Combining NIR spectroscopy with PLS-R, the moisture of the pulps under different conditions was estimated with R²p ranging from 0.89 to 0.98 for independent validation and root mean square error (RMSEP) ranging from 5.1 % to 18.3 %. The PLS-R models were applied to NIR spectra taken from other pulps and the estimates were consistent. The models showed robustness for monitoring pulps subjected to moisture variations
Spatial distribution of bedding attributes in an open compost-bedded pack barn system with positive pressure ventilation in brazilian winter conditions
No full textThe objective of this study was to characterize the dependence and spatial distribution of bedding attributes in an open compost-bedded pack barn (CBP) system with positive pressure ventilation during the winter period in Brazil. The study was conducted in July 2021, in the Zona da Mata region, Minas Gerais, Brazil. The bedding area (shavings and wood sawdust) was divided into a mesh with 44 equidistant points. At each point, the bedding temperature at the surface (tB-sur) and at a depth of 0.2 m (tB-20) and the air velocity at bedding level (vair,B) were measured, and bedding samples were collected. The bedding samples were used to determine the moisture level and pH at the surface (MB-sur e pHB-sur) and at a depth of 0.2 m (MB-20 and pHB-20). The spatial behavior of the variables was evaluated using geostatistics techniques. For all variables, the occurrence of strong spatial dependence was verified. Through the maps, it was observed that tB-sur, tB-20, MB-sur, MB-20, and vair,B showed high spatial variability, whereas pHB-sur and pHB-20 demonstrated low variation. On the surface, values of tB-sur 60% were observed. At the subsurface, there was a predominance of tB-20 60%, and pH > 9, which are indications of low bedding composting activity
The constitution of the pedagogical reasoning by future teachers in the context of the Pedagogical Residence Program
No full textArquivo retido, a pedido da autora, até julho de 2024.This master's thesis, developed within the framework of the Postgraduate Program in Education at the Federal University of Lavras (UFLA), linked to the Research Line of Professional Teaching Development, pedagogical practices and innovations and to the CNPq research group entitled: Grupo de Research on Teacher Training and Pedagogical Practices (FORPEDI), presents the final results of the research that aimed to investigate how the processes of Pedagogical Reasoning took place, in the context of the Pedagogical Residency Program, considering the pandemic context - Covid-19 in which the activities were developed, seeking to understand from the experiences reported by the residents in their reflective records, the constitution of the pedagogical reasoning existing in their activities and actions during the teaching and learning process in the Pedagogical Residency program. Based on this, we seek to answer questions such as: How did the activities developed in the context of the Pedagogical Residency program provide opportunities for the development of Pedagogical Reasoning? What knowledge emerged from the proposed pedagogical activities? What is the evidence of construction and acquisition of Pedagogical Reasoning in the exercise of teaching by residents? We used qualitative research as a methodology, and as an instrument for data collection the analysis of Reflective Records produced by residents throughout the program. 10 reflective records were selected, based on the selection criteria: presence of elements for the constitution of a Pedagogical Reasoning; Teaching learning; Teacher training in the context of the program and the approach to the research topic. Therefore, analyzing these data, our categories emerged: Teaching learning; The possibilities for the development of pedagogical reasoning; Dilemmas of teaching in the context of the pandemic: demand for pedagogical reasoning and the construction of new knowledge about teaching. We support theoretically in authors who discuss the themes of teaching learning (BOLZAN et. al 2014; MIZUKAMI 2010; SHULMAN 2014; NÓVOA 1995; BOLZAN 2009); on the Pedagogical Residency Program (CAPES 2018; BRASIL 2018; IMBERNÓN 2006); and on pedagogical reasoning processes (SHULMAN, 2014, 1986; MIZUKAMI, 2004; BARBOSA 2018). From this research, it was possible to understand that the professional learning processes of teaching residents happen through contact with dilemmas and/or difficult and conflicting situations of pedagogical practice. The analyzes showed that the involvement of these students with the regencies in the PRP, contributed to their formation as teachers, allowing: to relate the theory studied in the course with the pedagogical practice developed in the space of the schools; enhance processes of knowledge elaboration from the pedagogical practice and the challenges posed by it from its planning to its development; evidenced the reflective attitude towards the developed regencies and those who wanted to develop; fostering pedagogical reasoning processes. We conclude that the participation of students in the Pedagogical Residency Program allowed the development of pedagogical reasoning by future pedagogues, favoring the acquisition of a contextualized and meaningful professional attitude. It also allowed the redefinition of professional knowledge, favoring the formation of teaching learning and its professional identity.A presente dissertação de mestrado, desenvolvida no âmbito do Programa de Pós-graduação em Educação da Universidade Federal de Lavras (UFLA), vinculada a Linha de Pesquisa Desenvolvimento Profissional Docente, práticas pedagógicas e inovações e ao grupo de pesquisa do CNPq intitulado: Grupo de Pesquisa sobre Formação Docente e Práticas Pedagógicas (FORPEDI), apresenta os resultados finais da pesquisa que teve como objetivo investigar como se deu os processos do Raciocínio Pedagógico, no contexto do Programa Residência Pedagógica, considerando o contexto pandêmico – Covid-19 em que as atividades se desenvolveram, buscando compreender a partir das experiências relatadas pelos residentes nos seus registros reflexivos, a constituição do raciocínio pedagógico existente em suas atividades e ações durante o processo de ensino e aprendizagem no programa Residência Pedagógica. Baseado nisso, buscamos responder perguntas como: Como as atividades desenvolvidas no contexto do programa Residência Pedagógica oportunizaram o desenvolvimento do Raciocínio Pedagógico? Quais conhecimentos emergiram das atividades pedagógicas propostas? Quais as evidências de construção e aquisição do Raciocínio Pedagógico no exercício da docência pelos residentes? Utilizamos como metodologia a pesquisa qualitativa, e como instrumento para a coleta de dados a análise dos Registros Reflexivos produzidos pelos residentes ao longo do programa. Foram selecionados 10 registros reflexivos, a partir dos critérios de seleção: presença de elementos para a constituição de um Raciocínio Pedagógico; Aprendizagem da docência; A formação docente no contexto do programa e a aproximação com o tema de pesquisa. Logo, analisando esses dados, emergiram as nossas categorias: Aprendizagem da docência; Das possibilidades do desenvolvimento do raciocínio pedagógico; Dilemas do ensinar no contexto da pandemia: exigência do raciocínio pedagógico e da construção de novos saberes sobre a docência. Apoiamos teoricamente em autores que discutem sobre as temáticas da aprendizagem da docência (BOLZAN et. al 2014; MIZUKAMI 2010; SHULMAN 2014; NÓVOA 1995; BOLZAN 2009); sobre o Programa Residência Pedagógica (CAPES 2018; BRASIL 2018; IMBERNÓN 2006); e sobre os processos de raciocínio pedagógico (SHULMAN, 2014, 1986; MIZUKAMI, 2004; BARBOSA 2018). A partir dessa pesquisa, foi possível compreender que os processos de aprendizagem profissional da docência dos residentes, acontecem mediante o contato com dilemas e/ou situações difíceis e conflituosas da prática pedagógica. As análises mostraram que o envolvimento desses estudantes com as regências no PRP, contribuiu para a sua formação como professores, permitindo: relacionar a teoria estudada no curso com a prática pedagógica desenvolvida no espaço das escolas; potencializar processos de elaboração do conhecimento a partir da prática pedagógica e os desafios postos por ela desde o seu planejamento até o seu desenvolvimento; evidenciou a atitude reflexiva frente às regências desenvolvidas e àquelas que desejavam desenvolver; fomentando os processos de raciocínio pedagógico. Concluímos que a participação dos estudantes, no Programa Residência Pedagógica permitiu o desenvolvimento do raciocínio pedagógico pelas futuras pedagogas, favorecendo a aquisição de uma postura profissional contextualizada e significativa. Permitiu ainda a ressignificação de conhecimentos profissionais, favorecendo a constituição da aprendizagem da docência e sua identidade profissional
Dominant tree selection for height estimation and its impact on site classification for African mahogany stands
No full textAfrican mahogany plantations are increasing in Brazil, especially those planted with the species Khaya grandifoliola C. DC. Despite the interest in establishing plantations, there is a lack of studies in management practices for the genus. This makes it difficult to improve methodologies that optimise forest inventory activities, which are essential to support forest management decisions. Therefore, this study aimed to evaluate the effect of the number of trees selected to determine the mean dominant height, and to verify its impact on site classification of African mahogany stands. This will then optimise height sampling and ensure correct site index estimation. To determine the dominant height, 11 treatments were tested, with the selection of 1st to 11th thickest trees per plot, representing between 9 and 102 dominant trees per hectare. The effect of the treatments was evaluated using the values of the mean dominant height and metrics regarding site index classification (stability, stratification capacity and relationship with stand growth). Treatments with inclusion of more dominant trees resulted in a more stable site classification at the expense of a lower correlation with stand growth. Treatments using fewer dominant trees resulted in a greater allocation of plots in the upper site classes, showing that the number of trees used to calculate the dominant height influences the distribution of plots in different site classes. We concluded that Treatments 3 (27 trees ha−1) to 6 (55 trees ha−1) had the best performance, guaranteeing adequate site index estimation. The selection of at least 27 and a maximum of 55 dominant trees per hectare is recommended for African mahogany plantations with low planting densities
UAV-Toolkit
Full text linkBR 51 2020 002159 0CO02-Ciência (ciências humanas e sociais, naturais, biológicas, geociência, política
científica, desenvolvimento científico, história da ciência, filosofia da
ciência, metodologia científica, metodologia, pesquisa ou investigação,
pesquisa aplicada - indicar a área específica com outro código, instituição
de pesquisa); IN03-Engenharia (desenho técnico, engenharia metalúrgica, engenharia qu ímica, mec ânica,
automotiva, aeronáutica, naval, de produçã o, de teste); TP04-Eng Transp (de tráfego, aeronáutica, ferrovi ária, rodoviária, naval, automotiva)
Viabilidade técnica de anodos de sacrifício para evitar corrosão em aço galvanizado durante a fertirrigação
No full textArquivo retido, a pedido da autora, até março de 2024.Corrosion, a recurrent problem in irrigation, can lead to leaks, interruptions in activities, reduced system efficiency, among others, and its magnitude is directly related to the chemical composition of the solution that is drained, and may be even greater with the use of fertigation, as fertilizers become corrosive when in contact with water, and its degree of corrosivity varies with the type of source and its concentration. Cathodic protection is a technique used to reduce or control corrosion, in which a less noble metal is inserted into the structure, which is consumed by corrosion. The use of this technique associated with the metallic piping coating can be used to achieve a significantly greater protection, which would ensure the integrity of the piping for a longer time, however, it is not a technique commonly used in irrigation networks, which makes studies are needed to verify your benefits. For this reason, we sought to evaluate the effectiveness of using cathodic protection using the sacrificial anode method to control corrosion caused by fertigation solutions. For this, immersion tests were carried out with solutions of Urea and Potassium Chloride (KCl), at 10 g L-1, in contact with galvanized steel specimens, with cathodic protection of zinc, aluminum and magnesium anodes, in addition to a treatment without protection, simulating 350 hours of operation, in order to obtain the mass loss per area of the galvanized steel specimens and anodes. The influence of the cathode/anode area ratio on the protection of galvanized steel and on the consumption of aluminum anode in KCl solution was also verified. The results showed that with the use of cathodic protection it is possible to reduce the mass loss of galvanized steel exposed to KCl fertirrigation solutions, and that the aluminum anode is the most effective, since, with its use, one can have up to a 78% decrease in weight loss compared to unprotected treatment; however, for solutions containing Urea, the use of this method was not effective. With the increase in the aluminum cathode/anode area ratio, there was no significant difference in the weight loss of the galvanized steel and in the aluminum anode weight loss, thus making it more feasible to use the higher ratio (44:1).Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)A corrosão, problema recorrente na irrigação, pode levar a ocorrência de vazamentos, interrupções nas atividades, diminuição da eficiência do sistema, entre outros, e sua magnitude está diretamente relacionada à composição química da solução que é escoada, podendo ser ainda maior com o uso da fertirrigação, pois fertilizantes se tornam corrosivos quando em contato com a água, e seu grau de corrosividade varia com o tipo da fonte e sua concentração. A proteção catódica é uma técnica utilizada para reduzir ou controlar a corrosão, em que é inserido um metal menos nobre na estrutura, sendo este consumido pela corrosão. O uso desta técnica associada ao revestimento da tubulação metálica pode ser utilizada para alcançar uma proteção significativamente maior, o que asseguraria a integridade da tubulação por mais tempo, porém, não é uma técnica comumente utilizada em redes de irrigação, o que faz com que estudos sejam necessários para verificar seus benefícios. Por este motivo, buscou-se avaliar a eficácia do uso da proteção catódica pelo método de anodos de sacrifício, para controle da corrosão causada por soluções de fertirrigação. Para isso foram realizados ensaios de imersão com soluções de Ureia e Cloreto de potássio (KCl), a 10 g L-1, em contato com corpos de prova de aço galvanizado, com proteção catódica de anodos de zinco, alumínio e magnésio, além de um tratamento sem proteção, simulando 350 h de operação, a fim de obter a perda de massa por área dos corpos de prova de aço galvanizado e anodos. Também foi verificada a influência da razão de área catodo/anodo na proteção do aço galvanizado e no consumo do anodo alumínio, em solução de KCl. Os resultados mostraram que com o uso da proteção catódica é possível reduzir a perda de massa do aço galvanizado exposto a soluções de fertirrigação com KCl, e que o anodo de alumínio é o mais eficaz, já que, com seu uso, pode-se ter uma diminuição de até 78% na perda de massa em relação ao tratamento sem proteção; porém, para soluções contendo Ureia o uso deste método não foi eficaz. Com o aumento da razão de área catodo/anodo de alumínio não houve diferença expressiva na perda de massa do aço galvanizado e na perda de massa do anodo de alumínio, assim sendo mais viável o uso da maior razão (44:1)
Seed priming of Handroanthus heptaphyllus for the restoration of the mining fields
No full textSeed priming is a low-cost pre-sowing treatment used to improve germination and seedling establishment performance under adverse environmental conditions. The priming using signaling molecules, such as nitric oxide and hydrogen peroxide, act on plant growth and development alleviating the negative influence of abiotic stress by heavy metals. Thus, this work aimed to investigate the influence of priming with NO, H2O2, or their combination of Handroanthus heptaphyllus (Vell.) Mattos seeds on the germination and establishment of seedlings cultivated in iron mining tailings. The priming treatments were as follows: H2O, SNP (NO donor), H2O2 as well as SNP + H2O2. These primed seeds were cultivated in iron ore tailings or in a reference red oxisoil. The molecules used for the priming technique promoted distinct responses during seedlings’ establishment. Seedlings from NO-primed seeds exhibited higher Fe and Mn absorption in the tailing, with increased activities of the antioxidant system. The priming with H2O2 led to an avoidance strategy, with lower absorption of these elements by the seedlings. It can be concluded that NO and H2O2 induced different resistance mechanisms to Fe and Mn in H. heptaphyllus seedlings
MOLPROJ - Molecular orbital analysis by projection operators
Full text linkFísica e Química FQ13-Fís Molecl Física Molecular (ou física atômica, reação nuclear, estrutura molecular,
radiatividade, radiometria);
FQ14-Química (composto químico, subst ância combustível, substância química,
propriedade química, legação química, radical químico, reação qu ímica, composiçã o química, polímero inorgânico); FQ16-Fís-Quím (análise f ísico-química, processos físicos-químicos)
Sistema e dispositivo para monitoramento remoto de parâmetros diversos na avicultura
No full textTrata-se de um sistema e dispositivo para monitoramento remoto, pertencente ao setor industrial dos meios e equipamentos eletroeletrônicos utilizando hardwares e softwares destinados a coleta e avaliação de parâmetros variados, visando o controle, acompanhamento e adoção das providências e soluções necessárias de conformidade com as informações obtidas e registradas, para aplicação na criação de aves e de seus produtos derivados, permitindo o monitoramento da temperatura, umidade relativa, teor de amônia no ar, luminosidade e demais coordenadas relevantes, executadas por meio da aplicação do sensoriamento remoto usando a Internet como rede de comunicação de dados que podem ser armazenados e analisados posteriormente