Résumé L’objectif du travail est de documenter l’existence d’un modèle de punition-récompense dans les pratiques éducatives envers les mineurs, à Querétaro, région centre-bas du pays, au cours des années 1950; considéré comme une étape de transition vers la Modernité, dans un environnement socioculturel dominé par les institutions conservatrices. Les recherches précédentes ont montré l’existence de châtiments physiques et psychologiques dans les salles de classe, acceptés par la société, où les mineurs ne le considéraient pas comme de la violence, mais comme une activité d’enseignement. Les travaux universitaires se sont concentrés sur la cruauté des châtiments corporels et le rôle de l’enseignement dans l’exercice du pouvoir et de la domination, mais sans prêter attention aux enfances et aux dynamiques dans lesquelles, le correctif fait partie d’un quotidien où abondent aussi les stimuli basés sur la récompense. Pour montrer cela, une recherche a été menée dans le cadre de l’Histoire Sociale et Culturelle, en utilisant des sources officielles et des références telles que: photographies, publicités, bandes dessinées ou romans, à travers lesquelles sont mis en évidence certains des stimuli et des satisfactions que les familles, souvent par un lourd sacrifice économique, donnaient à leurs enfants pour pouvoir aller à l’école. Il ressort des conclusions que ce que l’on considérait auparavant comme des pratiques communes ne le sont plus au fil du temps, et ce qui était impensable, avec le progressisme, c’est maintenant la norme. Le rejet actuel de la violence physique et psychologique entre et vers la population scolaire ne fait pas exception.

Abstract This paper aims to document the existence of a punishment-reward model in educational practices towards minors in Querétaro, a central-bajío region in Mexico, during the 1950s. This decade was considered a transitional stage to Modernity, in a sociocultural environment dominated by conservative institutions. Previous research shows the existence of physical and psychological punishment in classrooms, accepted by society, where minors did not perceive them as violence, but as a regular part of teaching. Academic research focused on exposing the cruelty of physical punishment and on the role of teaching in exercising relations of power and domination, but without focusing on the children or the dynamics in which correction was part of everyday life where reward-based stimuli were also abundant. To demonstrate this, research was conducted under the approach of Social and Cultural History, using official sources and references such as photographs, advertisements, comic books, or novels, through which are evidenced some of the stimuli and satisfiers that families, often through a strong economic sacrifice, provided to their children so that they were able to go to school. Among the conclusions, it is noteworthy that what was once considered common practices, over time, is no longer so, and that what was unthinkable, with progressivism, is now the norm. The current rejection of physical and psychological violence among and towards the school population is no exception.

Resumen El objetivo del trabajo es documentar la existencia de un modelo de castigo-recompensa en las prácticas educativas hacia menores, en Querétaro, región centro-bajío del país, durante la década de 1950; considerada una etapa de transición a la Modernidad, en un entorno sociocultural dominado por las instituciones conservadoras. Las investigaciones previas muestran la existencia de castigos físicos y psicológicos en las aulas, aceptados por la sociedad, donde las y los menores no lo consideraban como violencia, sino quehacer docente. Los trabajos académicos se centraron en exhibir la crueldad de los castigos físicos y el papel de la docencia al ejercer relaciones de poder y dominación, pero sin prestar atención a las infancias ni a las dinámicas en las que, el correctivo es parte de una cotidianeidad en la que también abundan estímulos basados en la recompensa. Para dar muestra de ello, se desarrolló una investigación bajo el enfoque de la Historia Social y Cultural, usando fuentes oficiales y referencias como: fotografías, anuncios publicitarios, historietas o novelas, a través de las cuales se evidencian algunos de los estímulos y satisfactores que las familias, muchas veces mediante un fuerte sacrificio económico, daban a sus hijas e hijos para poder ir a la escuela. Entre las conclusiones destaca que, lo que antes se consideraban prácticas comunes, al paso del tiempo ya no lo son; y lo que era impensable, con el progresismo, ahora es la norma. El rechazo actual de la violencia física y psicológica entre y hacia la población escolar, no es la excepción.

Streszczenie Streszczenie Celem pracy jest udokumentowanie istnienia modelu kary i nagrody w praktykach edukacyjnych wobec nieletnich w Querétaro, regionie środkowo-zachodnim kraju, w latach 1950-1960; okres ten uważany jest za etap przejścia do nowoczesności, w społeczno-kulturowym środowisku zdominowanym przez konserwatywne instytucje. Badania wcześniejsze pokazują istnienie kar fizycznych i psychicznych w salach lekcyjnych, akceptowanych przez społeczeństwo, gdzie nieletni nie traktowali tego jako przemocy, a jako działalność pedagogiczną. Prace akademickie skupiały się na ujawnianiu okrucieństwa kar fizycznych i roli nauczycieli w wywieraniu relacji władzy i dominacji, ale bez zwracania uwagi na dzieciństwo ani dynamikę, w której kara jest częścią codzienności, obok obfitujących w bodźce opartych na nagrodzie. Aby to udowodnić, przeprowadzono badania z wykorzystaniem podejścia historii społecznej i kulturowej, korzystając z oficjalnych źródeł i odniesień, takich jak: fotografie, reklamy, komiksy lub powieści, poprzez które ukazano niektóre bodźce i zaspokajacze, które rodziny, często kosztem dużego poświęcenia ekonomicznego, dawały swoim córkom i synom, aby mogły chodzić do szkoły. Wnioski wskazują, że to, co kiedyś uważano za powszechne praktyki, z czasem przestaje nimi być; a to, co było nie do pomyślenia, stało się teraz normą dzięki postępowi. Obecny sprzeciw wobec przemocy fizycznej i psychicznej wśród i wobec populacji szkolnej nie jest wyjątkiem.

ABSTRACT Tamarind (Tamarindus indica L.) is a species with promising potential for commercial production; therefore, studies involving practices of conducting culture in the initial stage are essential. The present study aimed to evaluate different shading levels and substrate compositions in the seedling production of tamarind. The experimental design was completely randomized in a 4×4 factorial scheme, four levels of shading (0%, 18%, 30%, and 50%) and four substrates (pine bark-based substrate pure and mixed with 50% vermiculite, and sphagnum peat-based substrate pure and mixed with 50% vermiculite), with four replicates of four seedlings. Growth and biometric relationships were evaluated at 40 and 98 d after transplantation (DAT). The results reported that seedlings formed on the sphagnum peat-based substrate on pure or associated with vermiculite at 98 DAT had a height greater than 35 cm and a total 8.5 g DM. In contrast, seedlings produced in pine bark-based substrate did not reach 20 cm in height and had less than 3 g total DM. The condition of 30% and 50% shading promoted greater growth in height, reaching an average height greater than 40 cm, while in the full sun environment, seedlings showed an average of less than 35 cm; however, for the other variables, full sun environment did not differ from 30% shading, producing good quality seedlings. Thus, the cultivation of seedlings in an environment with 0% or 30% shading, associated with the sphagnum peat-based substrate pure or mixed with 50% vermiculite promoted the production of tamarind seedlings with vigorous growth. In the best environments, the best substrates increased, on average, 41.3% number of leaves, 80.5% shoot dry mass, 56.8% root dry mass, and 71.0% total dry mass. In the best substrates, the best environments increased, on average, 18.0% number of leaves, 20.7% shoot dry mass, 8.7% root dry mass, and 14.3% total dry mass.

ABSTRACT Chrysanthemum (Dendranthema grandiflora) is the second most produced and commercialized ornamental plant in the world. Measuring leaf area through non-destructive methods is fundamental for studies on its growth and production. The estimation of leaf area by linear dimensions of the leaves can be a strategy for this purpose. The objective of this study was to find allometric equations to estimate the leaf area of chrysanthemum. The linear, linear without intercept, quadratic, cubic, power, and exponential regression models were used for the analysis. The choice of equations was based on the highest coefficients of determination. The non-destructive method using allometric models has accuracy for estimating the leaf area (LA) of chrysanthemum from the product between leaf length (L) and leaf width (W). The LA of chrysanthemum can be estimated using the equation ŷ = 0.6611*LW0.9490 (L - leaf length; W - leaf width). This equation will allow researchers and producers to determine leaf area non-destructively.

RESUMO O crisântemo (Dendranthema grandiflora) é a segunda planta ornamental mais produzida e comercializada no mundo. A medição da área foliar por métodos não destrutivos é fundamental para estudos sobre seu crescimento e produção. A estimativa da área foliar por dimensões lineares das folhas pode ser uma estratégia para este fim. O objetivo deste estudo foi encontrar equações alométricas para estimar a área foliar do crisântemo. Os modelos de regressão linear, linear sem intercepto, quadrático, cúbico, potência e exponencial foram utilizados para a análise. A escolha das equações foi baseada nos maiores coeficientes de determinação. O método não destrutivo por meio de modelos alométricos tem acurácia para estimar a área foliar (AF) do crisântemo a partir do produto entre o comprimento da folha (C) e a largura da folha (L). A AF do crisântemo pode ser estimada pela equação ŷ = 0,6611*CL0,9490 (C - comprimento da folha; L - largura da folha). Essa equação permitirá que pesquisadores e produtores determinem a área foliar de forma não destrutiva.

ABSTRACT The efficiency of recurrent selection depends, among other factors, on the estimation of parameters that guide the breeder to obtain genetic gains for multiple traits. The aim of this research was to estimate genetic and phenotypic parameters of maize populations during the third cycle of recurrent selection for traits of interest. The populations CRE-01 and CRE-02, potential for resistance to corn stunt, were described using genetic and phenotypic parameters of variance components, heritability, variation indices and correlation between 16 agronomic traits. Direct and indirect selection gains were estimated for each trait and considering the Smith and Hazel, Mulamba and Mock and Z index. Both populations have genetic variability for the traits. High heritability estimates were obtained for most of the traits, which associated with the genetic variability, indicate that these populations may show continuous gains with recurrent selection. All selection indexes provided satisfactory genetic gains, but the Z index was the most promising considering the results of both populations.

RESUMO: A descompactação do solo é uma alternativa para o cultivo da soja em áreas de arroz, mas pode afetar o desenvolvimento do arroz irrigado em rotação. O objetivo do estudo foi avaliar o efeito remanescente da escarificação do solo realizada antes do cultivo da soja, sobre o uso da água de irrigação, o rendimento de grãos e parâmetros operacionais da semeadura do arroz, realizada na safra seguinte. A escarificação do solo foi feita no mês de setembro de 2017, anteriormente à soja na safra 2017/18 e o experimento de arroz foi conduzido na safra 2018/19. Os tratamentos foram:escarificação e não escarificação do solo. A escarificação aumentou a macroporosidade, a microporosidade e a porosidade total e diminuiu a densidade do solo. O cultivo do arroz reduziu a macroporosidade e aumentou a microporosidade. Não se observou influência do manejo de escarificação do solo sobre os parâmetros operacionais na semeadura do arroz. O solo escarificado necessitou 5,3 % a mais de água para irrigação do arroz, em relação ao solo não escarificado. Conclui-se que a escarificação do solo antes do cultivo da cultura da soja tem efeito remanescente em arroz na safra seguinte, mantendo maior porosidade do solo em relação à área não escarificada e elevando a quantidade de água necessária para irrigação do arroz cultivado na sequência. Não se verificou interferência da escarificação em parâmetros operacionais da semeadura e sobre o rendimento de grãos do arroz.

ABSTRACT: Soil decompaction is an alternative for soybean cultivation in rice areas, but it can affect the growth of irrigated rice in rotation. The objective of the study was to evaluate the effects of soil deep tillage performed before soybean cultivation on rice irrigation water, grain yield, and operational parameters of rice sowing carried out in the following crop season. Soil scarification was implemented in September 2017, prior to soybean crop season in the 2017/18 crop, and the rice experiment was conducted in the 2018/19 season. Treatments were: soil with scarification and soil without scarification. Deep tillage decreased soil density and increased macroporosity, microporosity, and total porosity. Rice cultivation decreased macroporosity and increased microporosity. Soil scarification management had no influence on operational parameters in rice sowing. Soil with scarification required 5.3% more water for rice irrigation than soil without deep tillage. In conclusion, soildeep tillage before the cultivation of soybean crop has effects on rice in thefollowing crop season, maintaining greater soil porosity in relation to the non-deep tillage area and increasing the amount of water needed for irrigation of rice cultivated in the sequence. Deep tillage did not affect sowing operational parameters and rice grain yield.

ABSTRACT: The knowledge of water consumption and the efficiency of water use by crops is extremely important in the elaboration of agronomic and hydraulic projects of hydroponic systems. Thus, the present study determined the water consumption and water use efficiency of ‘Biquinho’ pepper cultivated in the hydroponic system using seven levels of electrical conductivity of the nutrient solution (ECsol) of 2.70, 3.64, 4.58, 5.28, 6.09, 6.90, and 7.77 dS m-1 and six replicates in randomized blocks. The hydroponic system used was the Nutrient Film Technique (NFT). The water consumption per plant was determined at an interval of ten days in the crop cycle (120 days after transplanting). The maximum mean daily water consumption was equal to 5.88 L plant-1 during the period 111-120 DAT, for ECsol of 4.58 dS m-1. The maximum water consumption for the crop cycle (120 DAT) was 275.66 L per plant for an estimated ECsol = 4.11 dS m-1. The highest water use efficiency (WUE), based on the total production of fruit fresh mass (ripe and unripe fruits) of ‘Biquinho’ pepper was 10.84 kg m-3 up to an estimated ECsol of 5.18 dS m-1, with an exponential reduction thereafter. The salinity of the nutrient solution, biomass production, and evapotranspiration are factors that influence the most water consumption of ‘Biquinho’ pepper.

RESUMO: O conhecimento do consumo hídrico e eficiência do uso da água pelas culturas são extremamente importantes para o dimensionamento de sistemas agronômicos e projeto hidráulico dos sistemas hidropônicos. Neste contexto, o presente estudo determinou o consumo de água e a eficiência do uso da água da pimenta ‘Biquinho’ cultivada no sistema hidropônico utilizando sete níveis de condutividade elétrica da solução nutritiva (CEsol) de 2,70, 3,64, 4,58, 5,28, 6,09, 6,90 e 7,77 dS m-1 e seis repetições em blocos casualizados. O sistema hidropônico utilizado foi a técnica do fluxo laminar de nutrientes. O consumo hídrico por planta foi determinado em um intervalo de dez dias no ciclo da cultura (120 dias após o transplantio). O consumo hídrico médio diário máximo foi igual a 5,88 L planta-1 no período de 111-120 DAT, para a CEsol de 4,58 dS m-1. O consumo máximo de água para o ciclo da cultura (120 DAT) foi de 275,66 L por planta para uma estimada CEsol = 4,11 dS m-1. A maior eficiência do uso da água (EUA) observada foi de 10,84 kg m-3 (frutos maduros e não maduros) até ao CEsol estimada de 5,18 dS m-1, com posterior redução exponencial. A salinidade da solução nutritiva, a produção de biomassa e a evapotranspiração são fatores que mais influenciam o consumo de água da pimenta ‘Biquinho’.

ABSTRACT The aim of this study was to analyse patterns of spatial dispersal in Ceratitis capitata using two types of attractive traps and propose a predictive model of pest dispersal with the aim of determining management zones for decision-making. The experiment was conducted in an orchard of the ‘Palmer’ mango in the district of Belo Campo, Bahia. Sampling was carried out using McPhail and Jackson traps. The pattern of spatial dispersal in C. capitata was determined using the Perry and Mead Index of Dispersion, the Morisita Index, and the Local Moran index (LISA). The spatial variability of the abundance of C. capitata was obtained by geostatistical analysis, with the indicator kriging method used to prepare the location and spatial distribution maps. The Perry and Mead Index of Dispersion and the Morisita Index showed an aggregated pattern of spatial dispersal, whereas the Moran Local index showed a random pattern from 7 DFSH (days from the start of the harvest) to 35 DFSH, and an aggregated pattern at 42 DFSH. The SDI was strong at 7 and 35 DFSH and moderate at 14, 28 and 42 DFSH. The dispersal patterns of C. capitata allow an exponential predictive model to be produced, outlining strategies for exponential management zones of C. capitata, and detecting which places have the highest risk of the pest occurring.

Abstract The objective of this research was to select orange-fleshed sweet potato clones with high stability, yield, and β-carotene content in different planting seasons, using a selection index. Joint analysis of experiments and analysis of responsiveness and stability by the GGE biplot method were performed for the variables yield, dry matter percentage, and root flesh color. The variables yield, dry matter, color and stability were used to estimate a selection index. The GGE biplot analysis indicated that there are differences among clones in stability for Yield. However, the percentage of dry matter and color of the roots show low interaction in the different environments. Because of that, stability for yield was included in the selection index, together with yield, dry matter, and root orange color intensity. Finally, the selection index based on stability, yield, dry matter percentage and root color was efficient in the selection of a new biofortified sweet potato cultivar. orangefleshed fleshed βcarotene β carotene seasons Yield However environments intensity Finally cultivar

Abstract BRS A705 is an early-maturing cultivar developed by Embrapa, recommended for irrigated cultivation. The plants have high tillering and moderate resistance to the main diseases. This cultivar has short stature, which confers a greater tolerance to lodging. It presents high yield and long and fine grains of excellent quality. A A70 earlymaturing early maturing Embrapa cultivation diseases stature lodging quality A7

ABSTRACT Straw management associated with furrow opener mechanisms under a no-tillage system can enable better yields in the corn crop. Thus, this study aimed to evaluate corn productivity under a no-tillage system as a function of furrowing mechanisms and oat straw management. This research was conducted in the 2019/2020 growing season in Pato Branco, Paraná, Brazil, in a factorial scheme consisting of furrow opener mechanisms (shank and double disk) and oat straw management (rolled, desiccated, and crushed), with four replications. Oat dry matter, furrow depth, furrow width, tilled soil area, emergence rate index, initial and final plant stand, initial and final plant height, initial and final stem diameter, ear insertion height, number of rows per ear, number of grains per row, ear length, ear diameter, thousand-grain weight, and productivity were evaluated. The results were subjected to analysis of variance by the F-test at a significance 5% probability and the means were compared by Tukey’s test. Corn development, yield, and productivity were more influenced by the furrow opener mechanisms, standing out the use of a shank compared to the double disk.

RESUMO Congea tomentosa é uma trepadeira indicada para cobertura de mandris, grades e cercas. A determinação da área foliar é útil para entender a relação planta-ambiente e facilitar estudos agronômicos sobre transpiração, necessidade de água, interceptação de luz e atividade fotossintética. O objetivo deste estudo foi obter uma equação alométrica para estimar a área foliar de C. tomentosa através da medição das dimensões foliares. As análises foram realizadas em 200 folhas de diferentes formas e tamanhos de 10 plantas adultas escolhidas aleatoriamente cultivadas em condições de campo. O comprimento da folha, a largura da folha, o produto do comprimento pela largura e a área foliar foram determinados. Modelos de regressão linear, linear sem intercepto, quadrático, cúbico, potência e exponencial foram utilizados para estimar a área foliar. O coeficiente de determinação, índice de concordância de Willmott, critério de informação de Akaike, raiz do quadrado médio do erro e índice BIAS foram usados para determinar o melhor modelo. A área foliar de C. tomentosa pode ser satisfatoriamente estimada por meio de um método não destrutivo que utiliza medidas de dimensões foliares. A equação ŷ = 0,63 × LW (Folha: L = comprimento, W = largura) estima a área foliar de C. tomentosa de forma prática e rápida, com 99,15% de precisão. A estimativa da área foliar de C. tomentosa utilizando modelos estatísticos é menos dispendiosa e de fácil acesso aos pesquisadores e produtores desta planta.

ABSTRACT Congea tomentosa is a climbing plant suitable for covering arbors, railings, and fences. Leaf area determination is useful in understanding the plant-environment relationship and facilitating agronomic studies on transpiration, water requirement, light interception, and photosynthetic activity. The objective of this study was to obtain an allometric equation to estimate the leaf area of C. tomentosa by measuring the leaf dimensions. Analyses were performed on 200 leaves of different shapes and sizes from 10 randomly chosen adult plants grown under field conditions. The leaf length, leaf width, product length and width, and leaf area were determined. Linear, linear without intercept, quadratic, cubic, power, and exponential regression models were used to estimate the leaf area. The coefficient of determination, Willmott’s concordance index, Akaike information criterion, root mean square error and BIAS index were used to determine the best model. The leaf area of C. tomentosa can be satisfactorily estimated using a non-destructive method that uses measurements of leaf dimensions. The equation ŷ = 0.63 × LW (Leaf: L = length, W = width) estimates the leaf area of C. tomentosa in a practical and fast way, with 99.15% of precision. Estimation of the leaf area of C. tomentosa using statistical models is less expensive and easily accessible to researchers and producers of this plant.

RESUMO O objetivo desse trabalho foi avaliar o efeito da aplicação via solo de doses de boro (B), com ou sem adubação com zinco (Zn), sobre o crescimento, componentes de produção e produtividade do Milho em Neossolo Litólico distrófico, com baixos teores de B e Zn. O delineamento experimental utilizado foi blocos casualizados, em esquema fatorial 6 x 2, correspondente a seis doses de (B) aplicadas no solo (0, 1, 2, 3, 4 e 5 kg ha-1) e, sem e com adubação de Zn (2,0 kg ha-1 de Zn), ambas realizadas na semeadura, com quatro repetições. No estádio fenológico R1, foram avaliadas as variáveis de crescimento: diâmetro de colmo e altura de plantas, juntamente com o índice SPAD de clorofila. No estádio fenológico R6 foram analisados comprimento da espiga; massa de mil grãos, produtividade e dose de máxima eficiência (DME). A adubação com boro e zinco aumenta a produtividade do milho em solo com textura franco-argilo arenosa e baixos teores desses elementos, existindo sinergismo na absorção e metabolismo da planta quando se aplica 1,0 kg ha-1 de B juntamente com 2,0 kg de Zn ha-1 via solo no sulco de plantio. Neste estudo, as doses de máxima eficiência técnica para produtividade de grãos foi de 3,29 e 4,31 kg de B ha-1 para os tratamentos sem e com adubação com Zn.

ABSTRACT The objective of this work was to evaluate the effect of soil application of different boron (B) rates to the soil, with and without application of zinc (Zn), on growth, production components, and grain yield of maize crops grown in a Lithic Quartzipsamment with low B and Zn contents. A randomized block experimental design was used, in a 6×2 factorial arrangement corresponding to six B rates (0, 1, 2, 3, 4, and 5 kg ha-1), with and without application of Zn (2.0 kg ha-1), applied to the soil at sowing, with four replications. Growth variables (stem diameter and plant height), and chlorophyll SPAD index were evaluated at the R1 phenological stage. Maize ear length, one-thousand grain weight, and grain yield, and the B maximum efficiency rate were evaluated at the R6 phenological stage. Application of B and Zn to the soil increases maize grain yield in soils with sandy clay loam texture and low B and Zn contents; the plant absorption and metabolism indicated synergism between these elements when using soil applications of 1.0 kg ha-1 of B combined with 2.0 kg ha-1 of Zn to the planting furrows. The rates with maximum technical efficiency for grain yield were 3.29 and 4.31 kg of B ha-1 in treatments without and with application of Zn, respectively.

RESUMO A palma forrageira (Opuntia fícus-indica Mill) apresenta-se como forrageira importante para o Nordeste Brasileiro, devido a sua adaptação às condições edafoclimáticas da região, especialmente nos períodos de estiagens. O presente estudo teve objetivo de investigar os efeitos de dietas baseadas em palma forrageira associada a diferentes fontes de fibras no consumo (matéria seca e água), digestibilidade, produção de proteína microbiana, balanço de compostos nitrogenados e desempenho de vacas leiteiras sindi criadas em regiões semiáridas. As silagens utilizadas foram: atriplex (Atriplex nummularia Lindi.), sorgo (Sorghum bicolor (L.) Moench), gliricídia (Gliricidia sepium (Jacq.) Walp. ) e maniçoba (Manihot pseudoglaziovii Pax & K. Hoffm.), que foram incluídas nas dietas à base de palma forrageira (relação 58:42 volumoso: concentrado). As vacas foram distribuídas em delineamento Quadrado Latino duplo 4x4 com duração de 12 dias cada período. Para consumo de água houve diferenças (P<0,05) para dieta contendo silagem de atriplex (19,42 L/d). A dieta com silagem de sorgo apresentou menor coeficiente (P<0,05) digestibilidade da matéria seca (48,71 %) em relação ao tratamento de silagem de atriplex (68,46 %). A síntese microbiana foi maior (P<0,05) para a dieta com silagem de atriplex em relação ao tratamento que continha silagem de gliricídia (115,01 e 80,07 g de PBmic/kg de NDT), respectivamente. As silagens avaliadas associadas a palma forrageira podem ser utilizadas em dietas para vacas da raça Sindi em lactação sem influenciar o consumo diário de matéria seca, sem alterar a produção e gordura do leite, a síntese de proteína microbiana e o balanço de compostos nitrogenados.

ABSTRACT Forage cactus (Opuntia ficus-indica Mill) is an important forage resource in the Northeast region of Brazil due to its adaptation to the edaphoclimatic conditions of the region, mainly to the drought periods. The objective of this work was to assess the effects of diets with forage cactus combined with different sources of fibers on dry matter and water intakes, digestibility, microbial protein production, balance of nitrogen compounds, and performance of Red Sindhi cows in the Semiarid region of Brazil. The silages used were prepared from plants of Atriplex nummularia Lindi., Sorghum bicolor (L.) Moench, Gliricidia sepium (Jacq.) Walp., and Manihot pseudoglaziovii Pax & K. Hoffm. They were included in forage cactus-based diets at a roughage to concentrate ratio of 58:42. The cows were distributed in a 4×4 double Latin square design with 12 days for each period. Water intake presented differences (p<0.05) when using the diet with A. nummularia silage (19.42 L d-1). The diet with S. bicolor silage resulted in lower (p<0.05) coefficient of digestibility of dry matter (48.71%) than the diet with A. nummularia silage (68.46%). The diet with A. nummularia silage resulted in higher (p<0.05) microbial synthesis than that with G. sepium silage, 115.01 and 80.07 g CPmic kg-1 TDN, respectively. The silages evaluated, combined with forage cactus, can be used as diets for lactating Red Sindhi cows without affecting the daily dry matter intake, milk production, fat content, microbial protein synthesis, and balance of nitrogen compounds.

Resumo Fundamento: A (-)-carvona é um monoterpeno encontrado em óleos essenciais com atividade antioxidante e anti-inflamátoria. Objetivos: O objetivo deste estudo foi analisar a propriedade antiarrítmica da (-)-carvona no coração de rato e seus efeitos sobre a sinalização de Ca+2 intracelular. Métodos: Os efeitos da (-)-carvona foram avaliados sobre a contratilidade atrial (0,01 – 4 mM) e ventricular (0,5 mM), e no eletrocardiograma (0,5mM). A fração de encurtamento, a corrente de cálcio do tipo L (ICa,L) e a sinalização de Ca+2 foram medidas no cardiomiócito isolado (0,5 mM). O efeito antiarrítmico foi avaliado no modelo de arritmia induzida por sobrecarga de cálcio (0,5 mM) (n = 5). Um p < 0,05 foi adotado como nível de significância estatística. Resultados: No átrio, a (-)-carvona causou inotropismo negativo de maneira concentração-dependente (EC50 0,44 ± 0,11 mM) e diminuiu o inotropismo positivo induzido pelo CaCl2 (0,1 – 8,0 mM) e BAY K8644 (5 - 500 nM), um agonista de canal de cálcio do tipo L. Em coração isolado, a (-)-carvona (0,5mM) reduziu a contratilidade ventricular em 73% e a frequência cardíaca (em 46%), aumentou o Pri (30,7%, tempo desde o início da onda P até a onda R) e o QTc (9,2%, uma medida de despolarização e repolarização dos ventrículos), sem mudar a duração do complexo QRS. A (-)-carvona diminuiu a fração de encurtamento (61%), a (ICa,L) (79%) e o transiente intracelular de Ca+2 (38%). Além disso, a (-)-carvona apresentou ação antiarrítmica, identificada pela redução do escore de arritmia (85%) e ocorrência de fibrilação ventricular. Conclusão: A (-)-carvona reduz a entrada de Ca+2 através de canais de Ca+2 do tipo L e, assim, diminui a contratilidade cardíaca e o Ca+2 intracelular e apresenta promissora atividade antiarrítmica no coração de ratos.

Abstract Background: (-)-Carvone is a monoterpene found in essential oils with antioxidant and anti-inflammatory activity. Objective: The aim of this paper was to analyze the antiarrhythmic property of (-)-carvone in the rat heart and its effects on the intracellular Ca2+ signaling. Methods: The effects of (-)-carvone were evaluated on the ventricular (0.5 mM) and atrial contractility (0.01 – 4 mM) and on electrocardiogram (0.5 mM). Fractional shortening, L-type calcium current (ICa,L) and Ca2+ signaling were measured in the isolated cardiomyocyte (0.5 mM). Antiarrhythmic effect was evaluated in arrhythmia model induced by calcium overload (0.5 mM) (n = 5). P < 0.05 was used as the significance level. Results: In the atrium, (-)-carvone evoked negative inotropism that was concentration-dependent (EC50 0.44 ± 0.11 mM) and decreased the positive inotropism evoked by CaCl2 (0.1 to 8.0 mM) or BAY K8644 (5 to 500 nM), an agonist of L-type Ca2+ channel. In isolated heart, (-)-carvone (0.5 mM) promoted reduction of ventricular contractility (73%) and heart rate (46%), increased PRi (30.7%, time from the onset of the P wave until the R wave) and QTc (9.2%, a measure of the depolarization and repolarization of the ventricles) without changing the QRS complex duration. (-)-Carvone decreased the fractional shortening (61%), ICa,L (79%) and Ca2+ intracellular transient (38%). Furthermore, (-)-carvone showed antiarrhythmic action, verified by decrease of the arrhythmia score (85%) and occurrence of ventricular fibrillation. Conclusion: (-)-Carvone decreases Ca2+ entry through L-type Ca2+ channels, reducing the cardiac contractility and intracellular Ca2+, and, therefore, presenting promising antiarrhythmic activity in the rat hearts.