Physiology and morphology of rice plants with silicon supplementation and Dietholate seed treatment under water deficit

Silicon is an enzyme stimulator that promotes signaling for the production of antioxidant, osmoprotective compounds and attenuates interference in photosynthesis in rice plants subjected to water deficit. The aim of this study was to evaluate the possible effects of silicon as a stress reliever in rice plants grown from seeds treated with dietholate under of water deficit conditions. The experimental design was fully randomized with three replicates, 144 experimental units consisting of pots containing 4.4 pounds soil, and a 3x2x2x4 factorial arrangement: three soil water conditions (50% and 100% of soil water retention capacity and water blade of 5.0 cm); two cultivars (IRGA 424 RI and Guri INTA CL); two sources of Si (sodium and potassium metasilicate); and four Si rates (0; 4.0; 8.0 and 16 g L-1). Silicon boosted stomatal density; induced an increase in the maximum photochemical efficiency of photosystem II (PSII) under both water deficit and optimal conditions, boosting photosynthesis; and increased effective quantum yield of PSII and levels of total dry mass. Thus, silicon attenuated the effects of water deficit in plants grown from seeds treated with dietholate

Construção de colméia Langstroth com cimento-vermiculita

Exfoliated vermiculite is a light-weight and cheap product that, because of its thermal resistance, has become a valuable insulating material. With regard to its use in beekeeping, this research tested whether the box for honey bees constructed with cement-vermiculite mortar (CVM) presents physical characteristics similar to those of wood. The experiment was carried out at Seropédica, RJ, Brazil, for eight months. The cement-vermiculite mortar was compared with a control material (pinewood), in the construction of Langstroth boxes and boards, in a completely randomized design, with respect to thermal control, thermal conductivity and its capacity to absorb and lose water. The production cost for a CVM box was estimated. There were no internal temperature differences between CVM and wooden boxes. Thermal conductivity values for CVM and pinewood were similar. CVM absorbed more water and lost water faster than pinewood. Since CVM boxes can be easily constructed, at a low cost and with similar characteristics as traditional boxes, made of wood, the material can be recommended for use in non-migratory beekeeping.A vermiculita expandida é um material leve, barato e sua resistência térmica permite sua utilização como material isolante. Referente ao seu uso na Apicultura, esta pesquisa testou se a caixa para abelhas melíferas construída com argamassa cimento-vermiculita (ACV) apresenta características similares às da madeira. O estudo foi realizado em Seropédica (ERJ), Brasil, durante oito meses. Comparou-se a argamassa com o material controle, que foi a madeira pinho, em caixas de abelhas e em placas, em um delineamento inteiramente casualizado, quanto ao: controle térmico, a condutividade térmica, a capacidade de absorver e perder água. O custo de produção da caixa ACV para abelhas foi estimado. Não se observaram diferenças da temperatura interna entre as caixas de ACV e de madeira. A condutividade térmica foi similar nas placas de ACV e de madeira. As placas de ACV absorveram mais água, mas perderam mais rapidamente do que as de madeira. Considerando que a caixa de abelhas ACV é de fácil construção, de custo baixo e apresenta características similares a do material tradicional (madeira), este material pode ser recomendado para a apicultura, desde que não migratória

Chemoprotective Effect of Leaf Extracts of Cecropia distachya Huber (Urticaceae) in Mice Submitted to Oxidative Stress Induced by Cyclophosphamide

The objective of this work was to evaluate the chemoprotective effects of the embaúba Cecropia distachya Huber (two methanolic fractions: F1 and F2) on oxidative stress induced by cyclophosphamide (75 mg kg-1) in mice, as well as phytochemical analyzes by LC-MS/MS. In the experimental model, the fractions increased the hepatic and cardiac catalase (CAT), reduced glutathione (GSH) of the kidney and the heart. F1 increased platelet levels (PLT), hemogram (RBC), hematocrit (HCT) and hemoglobin (Hb) and F1 reduced hepatic lipid peroxidation (TBARS) and aspartate aminotransferase (AST) activity increased. F1 was attributed to possible hypoglycemic activity and possible immunosuppressive effects and F2 presented antimutagenic activity. In some cases, the fractions were also hepatotoxic. These results demonstrated that the fractions stimulate the antioxidant defenses, being hypoglycemic (F1) and antimutagenic (F2), and, the harmful effects attributed to the fractions may be the association of compounds that were not elucidated in this work. &nbsp

Development and Evaluation of the Internal Cladding Process of API 5L X70 Risers with Nickel-based superalloy 625 via PTA Welding

The Oil and gas exploration is one of the most strategic industrial sectors in the Brazilian economy. The discovery of deep water reserves adds more difficulty to the already problematic use of materials in equipment in extremely corrosive environments. With the objective of increasing the service life of the equipment, and consequently reducing the cost of maintenance and preventing against environmental catastrophes, it is common to use CRA claddings via welding processes, in which the nickel superalloy coatings stand out via the PTA welding process. In this context, the operation of internal cladding of risers becomes extremely complex due to the operational and metallurgical requirements imposed by the application. The present work aims at the development and empirical evaluation of the internal cladding procedure of risers with Nickelbased superalloy 625 via PTA welding process. From tests of cladding on plate, satisfactory preliminary parameters were reached for the performance of internal cladding tests on risers. From the adaptation of the welding parameters, comparative analyzes of three different procedures were carried out, with different weaving amplitude. Visual analysis and inspections were carried out via penetrating liquid and radiography, confirming the welding quality of all procedures performed. Still, proving the metallurgical quality of the developed procedures, analysis of chemical composition was carried out via EDX, presenting satisfactory results. Finally, a financial comparison of the process was elaborated, showing comparatively the consumption of powder and gas, and the time needed for internal cladding.Keywords: Coating; CRA; Nickel Alloy; Pipeline; Plasma Transferred Arc.

Anatomical changes in Urochloa Plantaginea and Urochloa Platyphylla under different soil moisture conditions

Urochloa plantaginea and Urochloa platyphylla are common weeds in the highland area. However, in recent years, they have been found in wetlands and poorly drained soils, but the biology and behavior of the species in these conditions are not known. Thus, the objective was to assess anatomical changes in plants of Urochloa plantaginea and Urochloa platyphylla grown under different soil moisture conditions, as well as the adaptive structures generated as a result of each environment. A completely randomized experimental design in the form of a 2x2 factorial design was used, with factor A being two species of Urochloa (U. plantaginea and U. platyphylla), and species B being three soil moisture conditions (50 and 100% FC and 5 cm water depth), with four repetitions. The assessments were performed by means of anatomical cuts, observing the number and diameter (micrometers - μm) of aerenchymas in stems, roots and leaves; total diameter and the central root cylinder (μm); diameter of the fistula medulla and cortex (μm) in stems; mesophyll thickness and leaf midrib (μm). It was found that, for the two species of Urochloa, the water depth condition induced an increase in the number and diameter of aerenchymas in roots and leaves and provided a larger diameter of the fistulous pith in stems. The diameter of the central cylinder and the thickness of the leaf mesophyll midrib were more compact at 50% FC, also, for both species. Therefore, the adaptive structures generated vary as a result of the field capacity of the soil

Silicon In the Growth of Rice Seedlings Pretreated with Dietholate and Subjected to Cold Stress

Silicon (Si) is an enzyme stimulator that can promote signaling for the production of antioxidant compounds, important in cellular detoxification of excess ROS accumulated during stress. The aim of the study was to evaluate the effects of Si on post-germination rice seeds in the mitigation of cold stress combined with stress induced by seed treatment with the dietholate protector. The experimental design was fully randomized with three replicates and a 3x2x2x4x2 factorial arrangement: three temperatures (5, 10 and 20 °C), two cultivars (IRGA 424 RI and Guri INTA CL), two seed pretreatments (with and without dietholate), four rates of Si (0; 4.0; 8.0 and 16 mg.L-1) and two sources of Si (sodium and potassium metasilicate). Seed pretreatment with dietholate reduced shoot and radicle length, especially at the lower temperatures of 5 and 10 °C. Sodium metasilicate as the source of Si was more efficient in boosting shoot and radicle length, both with and without pretreatment, regardless of temperature. Si was found to attenuate low-temperature stress and the impairment of shoot and radicle growth in rice seedlings grown from seeds pretreated with dietholate

Chloritic alteration in the east flank of the Caçapava Granite, State of Rio Grande do Sul: metasomatic evolution and associated Cu-Fe sulfides

This work investigated the origin and evolution of chloritites and chlorite bearing rocks and Cu-Fe sulfides, associated with sill and apophysis of the Caçapava Granite, which intrude in the dolomitic marbles of the Passo Feio formation, Terrane São Gabriel of the Sul-Riograndense Shield. The interaction of the granite fluids with the marbles generates high- and low-temperature mineral associations. The low-temperature alteration halos on the granitoid are mainly constituted of chlorite followed by albite titanite, sulfide and rare rutile. Chlorite, calcite and, eventually, serpentine, talc and sulfides constitute the low-temperature alteration in the country-rock marbles. The alteration halos are distributed in domains along the granitoid matrix as well as in stock-works or in hydrothermals breccias and its related fractures with chalcopyrite and pyrite. Important hydrothermal metassomatic alteration processes have been identified, notably, chloritization and albitization in the granitoid protholite. The alteration is progressive in the granitoid apophyses, with modifications since incipient to the rocks mainly constituted of chlorites, culminating in the generation of chloritites. The nucleation and growth of chlorite develops from the substitution of biotite and of plagioclase, or deposits it in empty spaces of carbonatic country-rocks. The mass balance by the isocon method indicates that the chloritization process developed through the enrichment of MgO and FeO and depletion in SiO2, K2O and Na2O in the protholite granitoids. The abundance pattern and distribution of rare-earth element (REE) belonging to Complex Granitic Caçapava do Sul. Geothermometry of chlorite composition indicates an average temperature between 280 and 300ºC for the chlorite formation.Este trabalho investigou a origem e a evolução de clorititos — rochas portadoras de clorita e/ou sulfetos de Cu-Fe —, associados a sills e apófises do Granito Caçapava que intrudem nos mármores dolomíticos da Formação Passo Feio, Terreno São Gabriel do Escudo Sul-Riograndense (ESRG). A interação dos fluidos graníticos com os mármores gera associações minerais de alta e baixa temperatura. Os halos de alteração de baixa temperatura nos granitoides são constituídos dominantemente por clorita seguida de albita, titanita, sulfetos e raro rutilo. Clorita, calcita e, eventualmente, serpentina, talco e sulfetos constituem a alteração de baixa temperatura nos mármores encaixantes. Os halos de alteração distribuem-se em domínios ao longo da matriz dos granitoides, bem como em stockworks ou em brechas hidrotermais e fraturas contendo calcopirita e pirita. Identificam-se processos importantes de alteração hidrotermal-metassomática, notadamente cloritização e albitização no protólito granitoide. A alteração é progressiva nas apófises granitoides com modificações desde incipiente até rochas compostas majoritariamente por cloritas, culminando com a geração de clorititos. A nucleação e o crescimento da clorita ocorre a partir da substituição da biotita e do plagioclásio ou deposita em espaços vazios na rocha carbonática encaixante. O balanço de massa pelo método da isócona indica que o processo de cloritização evoluiu por meio do enriquecimento de MgO e FeO e do empobrecimento em SiO2, K2O e Na2O dos protólitos granitoides. Os padrões de abundância e distribuição de elementos terras raras (ETR) indicam correlação direta das rochas portadoras de clorita e dos clorititos com fácies pertencentes ao Complexo Granítico de Caçapava do Sul. Geotermometria a partir da composição da clorita indica temperatura média entre 280 e 300ºC para formação das cloritas

Oficinas do Aprender: a Formação de Professores na Produção de Objetos de Aprendizagem Potencialmente Significativos

The excerpt we present is the result of workshops being carried out by members of the project entitled “Production and Sharing of Potentially Significant Digital Teaching and Learning Objects with Basic Education and Higher Education”, which aims to investigate the perceptions of teachers and students regarding teaching and learning processes, based on the production and sharing of didactic-pedagogical materials as Potentially Significant Digital Teaching and Learning Objects. In this sense, the project is based on an action research methodology and is being developed with teachers in initial training, from the Federal University of Santa Maria and Basic Education teachers from the municipal network of São Gabriel-RS. In view of this, the results regarding the reports of undergraduate students highlight the importance of working on playfulness in their training, empowering them to learn their teaching knowledge.  O recorte que apresentamos é resultante de oficinas que estão sendo realizadas por integrantes do projeto intitulado “Produção e Compartilhamento de Objetos Digitais de Ensino e de Aprendizagem Potencialmente Significativos com a Educação Básica e Ensino Superior”, que tem como objetivo investigar as percepções de professores e estudantes quanto aos processos de ensino e de aprendizagem, a partir da produção e compartilhamento de materiais didático-pedagógicos como Objetos Digitais de Ensino e Aprendizagem Potencialmente Significativos. Nesse sentido, o projeto está pautado em uma metodologia de pesquisa-ação e está sendo desenvolvido com docentes em formação inicial, da Universidade Federal de Santa Maria e professores/as da Educação Básica da rede municipal de São Gabriel-RS. Diante disso, os resultados referentes aos relatos dos licenciandos/as ressaltam a importância de trabalhar a ludicidade na sua formação, potencializando-os/as na aprendizagem de seus saberes docentes