Periods Of Weed Interference In Maize Crops Cultivated In The First And Second Cycles

The interference of weeds in maize production may be reflected in grain yield losses that vary as a function of the density, stage and degree of aggressiveness of the species present. In the agricultural ecosystem, crops and weeds demand light, water, nutrients and space, which are frequently not available in sufficient quantities, leading to competition. The aim of this work was to determine the period of interference of weed plants, in particular of naked crabgrass (Digitaria nuda) on maize crop in the first and second harvest. The treatments were defined as increasing periods of coexistence and increasing control of weed community (7, 14, 21, 28, 35, 42, 49, and 56 days), two more controls, a control including one with weed control until the end of the culture cycle and another with coexistence until the harvest. For each period, were evaluated the stand of maize plants, length of ear, number of grains per row, number of rows per ear, cob, 100-grain weight, and grain productivity. The data obtained were subjected to analysis of variance using the F test, with average treatments compared using Tukey's test at 5% probability. Crop productivity was evaluated by means of regressions, the critical periods of interference were estimated. The critical timing of weed removal was 25 days for both harvests. The critical weed free period was 54 and 27 days for the first and second harvest respectively. For the conditions of the first and second harvest, the critical period of weed control was of 29 and 2 days respectively.3752867287

Uma análise da aplicação empírica da produção mais limpa na manufatura no Journal of Cleaner Production

This article shows the results of a literature analysis of publications in the Journal of Cleaner Production, specifically papers that deal with the implementation of Cleaner Production (CP) in manufacturing. This work employs a systematic literature review considering a descriptive as well as a content analysis. Based on the results, it was found that the CP applied in manufacturing stands out in four main areas: 33% concerns the application of CP concepts, 12% of the areas refer to the application on-site recovery/reuse, 10% are geared technology changes, and 9% were used for better process control. It was also found that China and Australia are the countries with most applications of the concepts and practices of CP, based on the publications. Regarding barriers to implement CP, a wide range of factors that influence the application of CP in manufacturing was observed, which are economic, organizational, behavioral, technical and government.Keywords: Cleaner Production, manufacturing, literature review.O presente trabalho apresenta os resultados de uma análise de publicações no Journal of Cleaner Production especificamente que tratam da aplicação da Cleaner Production (CP) na manufatura. Para tanto, a pesquisa empregou uma revisão sistemática da literatura considerando uma análise descritiva e uma análise do conteúdo. Com base nas publicações analisadas, identificou-se que a CP aplicada na manufatura destaca-se em quatro áreas principais: 33% referente à aplicação dos conceitos de CP, 12% à aplicação on-site de recuperação/reutilização, 10% voltadas às mudanças de tecnologia e 9% para melhor controle do processo. Foi constatado também que a China e a Austrália são os países com maior aplicação dos conceitos e práticas da CP com base nas publicações analisadas. Em relação às barreiras para implementação da CP na manufatura, observou-se uma ampla gama de fatores de ordem econômica, organizacional, comportamental, técnica e governamental.Palavras-chave: produção mais limpa, manufatura, revisão da literatura

Uma análise da aplicação empírica da produção mais limpa na manufatura no Journal of Cleaner Production

This article shows the results of a literature analysis of publications in the Journal of Cleaner Production, specifically papers that deal with the implementation of Cleaner Production (CP) in manufacturing. This work employs a systematic literature review considering a descriptive as well as a content analysis. Based on the results, it was found that the CP applied in manufacturing stands out in four main areas: 33% concerns the application of CP concepts, 12% of the areas refer to the application on-site recovery/reuse, 10% are geared technology changes, and 9% were used for better process control. It was also found that China and Australia are the countries with most applications of the concepts and practices of CP, based on the publications. Regarding barriers to implement CP, a wide range of factors that influence the application of CP in manufacturing was observed, which are economic, organizational, behavioral, technical and government.Keywords: Cleaner Production, manufacturing, literature review.O presente trabalho apresenta os resultados de uma análise de publicações no Journal of Cleaner Production especificamente que tratam da aplicação da Cleaner Production (CP) na manufatura. Para tanto, a pesquisa empregou uma revisão sistemática da literatura considerando uma análise descritiva e uma análise do conteúdo. Com base nas publicações analisadas, identificou-se que a CP aplicada na manufatura destaca-se em quatro áreas principais: 33% referente à aplicação dos conceitos de CP, 12% à aplicação on-site de recuperação/reutilização, 10% voltadas às mudanças de tecnologia e 9% para melhor controle do processo. Foi constatado também que a China e a Austrália são os países com maior aplicação dos conceitos e práticas da CP com base nas publicações analisadas. Em relação às barreiras para implementação da CP na manufatura, observou-se uma ampla gama de fatores de ordem econômica, organizacional, comportamental, técnica e governamental.Palavras-chave: produção mais limpa, manufatura, revisão da literatura

Could more efficient utilization of ecosystem services improve soil quality indicators to allow sustainable intensification of Amazonian family farming?

In the Amazonian periphery, there are sources of numerous disservices, including deforestation, loss of wildlife habitat and biodiversity erosion. However, there are great opportunities to adopt appropriate agricultural management practices to take advantage of the benefits of ecosystem services for sustainable agricultural intensification. Thus, the aim of this work was to evaluate the effects of certain ecosystem services provided by combined use of legumes with residue of low- and high-quality on soil quality indicators, nitrogen use efficiency and sustainability of maize grain yield in infertile tropical soil. The overarching objective is to determine how ecosystem services can contribute to the improvement of land-use policy to ensure the sustainability of cultivated lands, in such a way that forest can be preserved by avoiding deforestation of other new areas through shifting cultivation systems. Four leguminous tree species were used, two with high-quality residues Leucaena leucocephala (leucaena) and Gliricidia sepium (gliricidia) and two with low-quality residues Clitoria fairchildiana (clitoria) and Acacia mangium (acacia). Maize grain yield was evaluated between 2011 and 2017 in these treatments. In 2018, to assess how ecosystem services affect crop performance, the treatments were divided into ten treatments with and without urea. We conclude that increased uptake of inorganic and organic N by maize resulting from improvement of the soil quality indicators may allow agricultural intensification. This improvement can help meet the challenges of sustainability and feasibility of agroecosystems of the Amazonian periphery by making the agroecosystem more productive year by year. Therefore, our results confirm that the utilization of an ecosystem services style approach can help meet the challenges of sustainability and feasibility in agrosystems of the Amazonian periphery. In addition, these results can contribute to the development of land-use policy in the Amazonian periphery, aiming for the intensification of agriculture in cropped areas to avoid deforestation of new areas from shifting cultivation systems

Neutrino properties and the decay of the lightest supersymmetric particle

Supersymmetry with broken R-parity can explain the neutrino mass squared differences and mixing angles observed in neutrino oscillation experiments. In the minimal model, where R-parity is broken only by bilinear terms, certain decay properties of the lightest supersymmetric particle (LSP) are correlated with neutrino mixing angles. Here we consider charginos, squarks, gluinos and sneutrinos being the LSP and calculate their decay properties in bilinear R-parity breaking supersymmetry. Together with the decays of charged scalars and neutralinos calculated previously this completes the proof that bilinear R-parity breaking as the source of neutrino masses will be testable at future colliders. Moreover, we argue that in case of GMSB, the decays of the NLSP can be used to test the model.Comment: 15 pages, 8 figure

Balanço do nitrogênio e fósforo em solo com cultivo orgânico de hortaliças após a incorporação de biomassa de guandu.

Os objetivos deste trabalho foram avaliar os efeitos de faixas de guandu (Cajanus cajan) e da incorporação da biomassa proveniente de sua poda na fertilidade do solo e na produtividade de três hortaliças sob cultivo orgânico. O delineamento usado foi de blocos casualizados completos em esquema de parcelas subsubdivididas com três repetições. As produtividades de beterraba, cenoura e feijão-de-vagem não foram afetadas pelos tratamentos. Nas parcelas onde não houve incorporação da biomassa de guandu, o balanço de nitrogênio no sistema foi negativo, ao passo que com a incorporação, esse balanço foi positivo. Embora tenha ocorrido balanço positivo para o fósforo nas parcelas sem a incorporação de biomassa de guandu, houve um aumento significativo na absorção desse elemento pelas hortaliças quando o material foi incorporado. O sistema de cultivo em aléias de guandu pode representar uma prática vantajosa para os produtores orgânicos, por contribuir na manutenção da fertilidade do solo

Effects of cholinergic stimulation with pyridostigmine bromide on chronic chagasic cardiomyopathic mice

The aim of the present study was to assess the effects of an anticholinesterase agent, pyridostigmine bromide (Pyrido), on experimental chronic Chagas heart disease in mice. To this end, male C57BL/6J mice noninfected (control:Con) or chronically infected (5 months) with Trypanosoma cruzi (chagasic:Chg) were treated or not (NT) with Pyrido for one month. At the end of this period, electrocardiogram (ECG); cardiac autonomic function; heart histopathology; serum cytokines; and the presence of blood and tissue parasites by means of immunohistochemistry and PCR were assessed. In NT-Chg mice, significant changes in the electrocardiographic, autonomic, and cardiac histopathological profiles were observed confirming a chronic inflammatory response. Treatment with Pyrido in Chagasic mice caused a significant reduction of myocardial inflammatory infiltration, fibrosis, and hypertrophy, which was accompanied by a decrease in serum levels of IFN\u3b3 with no change in IL-10 levels, suggesting a shift of immune response toward an anti-inflammatory profile. Lower nondifferent numbers of parasite DNA copies were observed in both treated and nontreated chagasic mice. In conclusion, our findings confirm the marked neuroimmunomodulatory role played by the parasympathetic autonomic nervous system in the evolution of the inflammatory-immune response to T. cruzi during experimental chronic Chagas heart disease in mice

Active Brownian Particles. From Individual to Collective Stochastic Dynamics

We review theoretical models of individual motility as well as collective dynamics and pattern formation of active particles. We focus on simple models of active dynamics with a particular emphasis on nonlinear and stochastic dynamics of such self-propelled entities in the framework of statistical mechanics. Examples of such active units in complex physico-chemical and biological systems are chemically powered nano-rods, localized patterns in reaction-diffusion system, motile cells or macroscopic animals. Based on the description of individual motion of point-like active particles by stochastic differential equations, we discuss different velocity-dependent friction functions, the impact of various types of fluctuations and calculate characteristic observables such as stationary velocity distributions or diffusion coefficients. Finally, we consider not only the free and confined individual active dynamics but also different types of interaction between active particles. The resulting collective dynamical behavior of large assemblies and aggregates of active units is discussed and an overview over some recent results on spatiotemporal pattern formation in such systems is given.Comment: 161 pages, Review, Eur Phys J Special-Topics, accepte