Elucidating how the chemical-nutritional composition of tomato is affected by the environment, season, and growing system

Tomatoes play an important nutritional role due to the chemical-nutritional composition of this fruit, and its common use in dishes and food products. Its fruits provide pronounced antioxidant properties to the human diet, because of the presence of vitamin C, carotenogenic compounds such as lycopene and β-carotene, and phytochemicals such as flavonoids. Despite this, the antioxidant function and carotenoid levels in tomato may present significant differences depending on the system of cultivation, growing season, and environment in which this vegetable is cultivated. In light of this, this study aimed to assess the effects of the cultivation system known as “Viçosa”, in relation to traditional tomato cultivation systems, over two seasons. This assessment was done both under field conditions and in a controlled environment. The nutritional aspects of the fruits, such as the levels of phenolic compounds, lycopene, beta-carotene, and antioxidant activity, were analyzed. The controlled environment in the autumn-winter season, associated with the Viçosa cultivation system, facilitated increases in the lycopene content. Furthermore, field cultivation provided an increase of 68% and 38% in the total phenolic concentration in tomato fruits, in the spring-summer and autumn-winter seasons, respectively. Field cultivation also provided an increase of 31% in the antioxidant activity of the fruits, compared with that of the controlled cultivation, in the autumn-winter season. The increase in the levels of total phenolics and antioxidant activity of fruits due to cultivation in the field represents an advantage as cultivation in this environment has a lower cost than cultivation in a controlled environment. The cultivation systems did not influence the chemical-nutritional aspects of fruits; moreover, the Viçosa system brings together aspects such as high productivity and profitability, without compromising the chemical-nutritional aspects of the fruits, thereby configuring a promising system for tomato production

Design-controlled synthesis of IrO2 sub-monolayers on Au nanoflowers: Marrying plasmonic and electrocatalytic properties

We develop herein plasmonic–catalytic Au–IrO2 nanostructures with a morphology optimized for efficient light harvesting and catalytic surface area; the nanoparticles have a nanoflower morphology, with closely spaced Au branches all partially covered by an ultrathin (1 nm) IrO2 shell. This nanoparticle architecture optimizes optical features due to the interactions of closely spaced plasmonic branches forming electromagnetic hot spots, and the ultra-thin IrO2 layer maximizes efficient use of this expensive catalyst. This concept was evaluated towards the enhancement of the electrocatalytic performances towards the oxygen evolution reaction (OER) as a model transformation. The OER can play a central role in meeting future energy demands but the performance of conventional electrocatalysts in this reaction is limited by the sluggish OER kinetics. We demonstrate an improvement of the OER performance for one of the most active OER catalysts, IrO2, by harvesting plasmonic effects from visible light illumination in multimetallic nanoparticles. We find that the OER activity for the Au–IrO2 nanoflowers can be improved under LSPR excitation, matching best properties reported in the literature. Our simulations and electrocatalytic data demonstrate that the enhancement in OER activities can be attributed to an electronic interaction between Au and IrO2 and to the activation of Ir–O bonds by LSPR excited hot holes, leading to a change in the reaction mechanism (rate-determinant step) under visible light illumination

Soil cover plants on water erosion control in the South of Minas Gerais

Water erosion is responsible for soil, water, carbon and nutrient losses, turning into the most important type of degradation of Brazilian soils. This study aimed to evaluate the influence of three cover plants under two tillage systems on water erosion control in an Argisol at south of Minas Gerais state, Brazil. The cover plants utilized in the study were pigeon pea, jack bean and millet, under contour seeding and downslope tillage. Experimental plots of 4 x 12 m, with 9% slope, under natural rainfall were used for the quantification of losses of soil, water, nutrients, and organic matter. One experimental plot was kept without plant cover (reference). Higher erosivity was observed in December and January, although a great quantity of erosive rainfall was detected during the whole raining period. Contour seeding provided a greater reduction of water erosion than downslope tillage, as expected. The jack bean under contour seeding revealed the lowest values of soil, water, nutrients and organic matter losses

Eletroestimulação na cicatrização de feridas cutâneas experimentais em coelhos

Feridas cutâneas crônicas e complicadas são frequentemente encontradas na rotina da medicina veterinária e, muitas vezes, transformam os tratamentos em verdadeiro desafio. A eletroterapia tem sido indicada como alternativa aos tratamentos convencionais, devido à sua capacidade de promover cicatrização. O objetivo deste trabalho é relatar um ensaio experimental utilizando a eletroestimulação (ES) na cicatrização de feridas cutâneas em coelhos. Para tanto, foram utilizados 10 coelhos Nova Zelândia, machos, hígidos, submetidos à anestesia geral para a indução experimental de duas feridas cutâneas de 1cm² localizadas no dorso, caudal à borda das escápulas. As lesões foram higienizadas com solução salina 0,9%, sendo a do lado direito tratada por ES e a do lado esquerdo, como controle. Para ES utilizou-se a frequência de 60Hz, por 10 minutos a cada dois dias, sendo aplicadas quatro agulhas de acupuntura em pontos equidistantes ao redor da lesão, a 0,5cm da borda. Os animais foram divididos em dois grupos, de oito e de 15 dias, conforme o período de tratamento e avaliação macroscópica e histopatológica. Não houve diferença significativa no tempo de cicatrização das lesões tratadas com ES. Porém, apresentaram qualidade tecidual, tanto na avaliação macro quanto microscópica, superior às do grupo controle. Com isso, é possível indicar a ES como tratamento de feridas cutâneas, por ser uma técnica eficiente, de fácil aplicação e de relativo baixo custo