QUALIDADE DAS ÁGUAS SUBTERRÂNEAS DE ÁREA IRRIGADA DA COMUNIDADE DE PAU BRANCO EM MOSSORÓ (RN)

A irrigação de culturas agrícolas sem o controle de alguns parâmetros de qualidade, associada ao uso indiscriminado de fertilizantes artificiais, tende a aumentar a poluição das águas superficiais e subterrâneas. Desse modo, o presente trabalho objetivou avaliar os níveis de qualidade da água subterrânea de uma propriedade agrícola de produção de melão irrigado, situada na comunidade de Pau Branco, em Mossoró-RN. Para a efetivação deste estudo, foram coletadas amostras de água de 13 poços tubulares, perfurados em uma área localizada no domínio de calcário Jandaíra, realizadas durante o ano de 2012. As amostras de água coletadas foram submetidas a algumas análises físico-químicas de parâmetros de qualidade da água, de acordo com o método APHA (2005), destacando-se a condutividade elétrica; concentração de nitrato e potencial hidrogeniônico. Os dados foram analisados por meio de estatística descritiva, utilizando-se, da média (M), do desvio padrão (DP), e dos valores mínimos e máximos desses dados. Para avaliar a precisão experimental dos dados, foi utilizado o coeficiente de variação (CV), conforme a classificação proposta por Pimentel-Gomes (1985). Foram empregados testes não paramétricos, visando ajustar os dados a uma distribuição normal com 5% de significância. Os parâmetros estudados, também, foram avaliados através dos gráficos de controle de qualidade de Shewhart. A partir da avaliação estatística, e de acordo com a classificação proposta por Ayers e Westcot (1999), constatou-se que os resultados, no período avaliado, dos valores de salinidade e de concentração de nitrato das águas desses poços foram classificados, quanto ao grau de restrição para uso, como de ligeiro a moderado. Os resultados dos valores médios de pH apresentaram limites aceitáveis, dentro de uma faixa normal, para utilização da água na irrigação, na cultura do melão

Macronutrient contents in rose crops under salinity levels and nitrogen:potassium ratios

Rose crops under fertigation in a protected environment is an alternative for production increase. However, the high dosages of fertilizers can lead to the salinization of soils in this environment. The aim of this study was to evaluate the effect of salinity caused by the excess of fertilizer application through fertigation associated with different nitrogen: potassium (N: K) ratios on macronutrient contents in rose crops. The study was performed in a randomized block design, arranged in a factorial scheme (5 x 3 + 1), with four repetitions, totaling 64 plots. The treatments were formed by combination of five initial levels of electrical conductivity (EC: 1.2; 2.3; 3.3; 4.3 e 5.5 dS m-1), three nitrogen: potassium (N: K) ratios (2:1; 1:2 and 1:3) and a control with N: K ratio (1: 1). Contents of N, K, Ca, Mg and S were evaluated in the stem, leaves and flowers. The levels of N, K, P, Ca and Mg in plant tissues are affected by the treatments at 245 days after transplanting. Leaves presented the highest levels of macronutrients, mainly nitrogen. TDR probe is a satisfactory tool in the management of fertigation.Rose crops under fertigation in a protected environment is an alternative for production increase. However, the high dosages of fertilizers can lead to the salinization of soils in this environment. The aim of this study was to evaluate the effect of salinity caused by the excess of fertilizer application through fertigation associated with different nitrogen: potassium (N: K) ratios on macronutrient contents in rose crops. The study was performed in a randomized block design, arranged in a factorial scheme (5 x 3 + 1), with four repetitions, totaling 64 plots. The treatments were formed by combination of five initial levels of electrical conductivity (EC: 1.2; 2.3; 3.3; 4.3 e 5.5 dS m-1), three nitrogen: potassium (N: K) ratios (2:1; 1:2 and 1:3) and a control with N: K ratio (1: 1). Contents of N, K, Ca, Mg and S were evaluated in the stem, leaves and flowers. The levels of N, K, P, Ca and Mg in plant tissues are affected by the treatments at 245 days after transplanting. Leaves presented the highest levels of macronutrients, mainly nitrogen. TDR probe is a satisfactory tool in the management of fertigation

Differencial rumen protozoa counting from steers fed Napier elephant grass (Pennisetum purpureum Schum) at different maturity stages

Napier grass (Pennisetum purpureum Schum) in-3 growing stages: a) 1,30 m tall and 17.54% dry matter; b) 2.35 m tall and 25.84% dry matter: and c) 3,25 m tall and 26.31% dry matter, was fed "ad libitum" to eight rumen fistulated steers all crossbred (5/8 european-zebu) weighting 220 kg, being fed 1,5 kg of a concentrate meal with 24.16% of crude protein. Treatments were compared in a completely randonmized design using the 4th week of each experimental period for rumen liquor sampling for differencial counts of the following protozoa: Entodinium, Diplodinium, Eudipiodinium and Polyplastron. Results showed Entodinium as 96.73% of total protozoa and its concentration per mililiter of rumen fluid decreased linearly as the plant matured (a = 18.2 x 104/ml; b = 12.1 x 104/ml; and c = 9.8 x 104/ml).Capim elefante Napier (Pennisetum purpureum Schum) colhido em quatro estádios de desenvolvimento: a) 1,30 m de altura e 17,54% de matéria seca; b) 2,35 m de altura e 25,84% de matéria seca; e c) 3,25 m de altura e 26,31% de matéria seca, foi fornecido “ad libitum" a 8 bovinos com 5/8 de sangue europeu-zebu, com 220 kg de peso vivo médio, providos de fístulas ruminais. Todos receberam 1,5 kg de uma mistura concentrada com 24,10% de proteína bruta. Os tratamentos foram comparados em um delineamento inteiramente casualizado, sendo que na quarta semana de cada período experimental colheram-se amostras de líquido de rúmen antes da oferta dos alimentos, para contagens diferenciais dos seguintes gêneros de protozoários ciliados e auferir suas concentrações por mililitro: Entodinium spp; Diplodinium spp; Eudiplodinium spp e Polyptastron spp. Os resultados mostraram que os protozoários ciliados do gênero Entodinium predominaram com 96,73% do total da população desses microorganismos. O número de Entodinium spp decresceu com a maturação da planta: a) 18,2 x 104/ml; b) 12,1 x 104/ml; e c) 9,8 x 104/ml

Uso de Rizobactérias na Fixação Biológica de Nitrogênio na Cultura do Amendoim

O amendoim é a quarta oleaginosa mais cultivada no mundo. Essa cultura necessita de alguns cuidados no seu cultivo, como a resistência a estresses bióticos e a fixação biológica de nitrogênio, necessitando de inoculantes específicos para seu cultivo. As rizobactérias promotoras de crescimento têm se mostrado eficiente em culturas leguminosas, onde as mesmas induzem resistência a patógenos e fornecem nutrientes capazes de proporcionar o crescimento ágil das plantas. Foram avaliados promoção de crescimento (comprimento e biomassa) e fixação biológica de nitrogênio (análise nutricional de N e número de nódulos). O uso de rizobactérias promotoras de crescimento torna-se uma prática viável na cultura do amendoim, onde a mesma juntamente com a FBN favorece no crescimento das plantas e na sustentabilidade da cultura no campo.Peanut is the fourth most cultivated oilseed in the world. This crop needs some care in its cultivation, such as resistance to biotic stresses and biological nitrogen fixation, requiring specific inoculants for its cultivation. Growth-promoting rhizobacteria have been shown to be efficient in leguminous crops, where they induce resistance to pathogens and provide nutrients capable of providing agile plant growth. Growth promotion (length and biomass) and biological nitrogen fixation (nutritional analysis of N and number of nodules) were evaluated. The use of growth-promoting rhizobacteria becomes a viable practice in the cultivation of peanuts, where it, together with FBN, favors the growth of plants and the sustainability of culture in the field

Cultivo da rúcula em substrato de fibra de coco sob solução nutritiva salina

Em função da baixa disponibilidade de água doce para a agricultura, o uso de água salina na produção de alimentos e a adoção do sistema hidropônico são alternativas para o semiárido. É necessário buscar alternativas para o uso condizente dessas águas com seu maior aproveitamento na produção vegetal e reduzir os impactos ambientais. Assim, o presente trabalho teve como objetivo avaliar o efeito da salinidade da solução nutritiva para rúcula (Eruca sativa L. cv. Cultivada) cultivada em substrato de fibra de coco sob condições protegidas. Foi utilizado o delineamento em blocos casualizados, arranjados em esquema fatorial 4x4, com quatro tipos de solução nutritiva de composição salina, adicionadas de NaCl (ST = 2,0; S1 = 3,5; S2 = 4,5 e S3 = 5,5 dS m-1), aplicadas em quatro épocas de desenvolvimento (primeira, segunda, terceira e quarta semana após o transplantio), com quatro repetições. Os resultados indicam que o aumento da salinidade da solução nutritiva não proporcionou redução para altura das plantas e número de folhas, sendo os teores de Na e Cl nas folhas classificado como aceitável para alimentação humana

Production of Hydrogen and their Use in Proton Exchange Membrane Fuel Cells

This work will show an overview of the hydrogen production from ethanol by steam reforming method, using distinct catalysts, resulting in low carbon monoxide content in H2 produced; a thermodynamic analysis of reforming employing entropy maximization, the ideal condition for ethanol, and other steam reforming reactions, the state of the art of steam reforming catalysts for H2 production with low CO content. Moreover, in the second part, there will be an overview of the use of hydrogen in a proton exchange membrane fuel cell (PEMFC), the fuel cell operational conditions, a thermodynamic analysis of PEMFC, the catalysts used in the electrodes of the fuel cell, consequences of the CO presence in the hydrogen fuel feed in PEMFC, and the operation conditions for maximum output power density

Electroconvulsive therapy use in adolescents: a systematic review

Abstract\ud \ud \ud \ud Background\ud \ud Considered as a moment of psychological vulnerability, adolescence is remarkably a risky period for the development of psychopathologies, when the choice of the correct therapeutic approach is crucial for achieving remission. One of the researched therapies in this case is electroconvulsive therapy (ECT). The present study reviews the recent and classical aspects regarding ECT use in adolescents.\ud \ud \ud \ud Methods\ud \ud Systematic review, performed in November 2012, conformed to the PRISMA statement.\ud \ud \ud \ud Results\ud \ud From the 212 retrieved articles, only 39 were included in the final sample. The reviewed studies bring indications of ECT use in adolescents, evaluate the efficiency of this therapy regarding remission, and explore the potential risks and complications of the procedure.\ud \ud \ud \ud Conclusions\ud \ud ECT use in adolescents is considered a highly efficient option for treating several psychiatric disorders, achieving high remission rates, and presenting few and relatively benign adverse effects. Risks can be mitigated by the correct use of the technique and are considered minimal when compared to the efficiency of ECT in treating psychopathologies

Dynamics and determinants of SARS-CoV-2 RT-PCR testing on symptomatic individuals attending healthcare centers during 2020 in Bahia, Brazil

RT-PCR testing data provides opportunities to explore regional and individual determinants of test positivity and surveillance infrastructure. Using Generalized Additive Models, we explored 222,515 tests of a random sample of individuals with COVID-19 compatible symptoms in the Brazilian state of Bahia during 2020. We found that age and male gender were the most significant determinants of test positivity. There was evidence of an unequal impact among socio-demographic strata, with higher positivity among those living in areas with low education levels during the first epidemic wave, followed by those living in areas with higher education levels in the second wave. Our estimated probability of testing positive after symptom onset corroborates previous reports that the probability decreases with time, more than halving by about two weeks and converging to zero by three weeks. Test positivity rates generally followed state-level reported cases, and while a single laboratory performed ~90% of tests covering ~99% of the state's area, test turn-around time generally remained below four days. This testing effort is a testimony to the Bahian surveillance capacity during public health emergencies, as previously witnessed during the recent Zika and Yellow Fever outbreaks

Genomic characterization of SARS-CoV-2 from an indigenous reserve in Mato Grosso do Sul, Brazil

BackgroundThe COVID-19 pandemic had a major impact on indigenous populations. Understanding the viral dynamics within this population is essential to create targeted protection measures.MethodsA total of 204 SARS-CoV-2 positive samples collected between May 2020 and November 2021 from an indigenous area in Mato Grosso do Sul (MS), Midwestern Brazil, were screened. Samples were submitted to whole genome sequencing using the Nanopore sequencing platform. Clinical, demographic, and phylogenetic data were analyzed.ResultsWe found the co-circulation of six main SARS-CoV-2 lineages in the indigenous population, with the Zeta lineage being the most prevalent (27.66%), followed by B.1.1 (an ancestral strain) (20.21%), Gamma (14.36%) and Delta (13.83%). Other lineages represent 45.74% of the total. Our phylogenetic reconstruction indicates that multiple introduction events of different SARS-CoV-2 lineages occurred in the indigenous villages in MS. The estimated indigenous population mortality rate was 1.47%. Regarding the ethnicity of our cohort, 64.82% belong to the Guarani ethnicity, while 33.16% belong to the Terena ethnicity, with a slightly higher prevalence of males (53.43%) among females. Other ethnicities represent 2.01%. We also observed that almost all patients (89.55%) presented signs and symptoms related to COVID-19, being the most prevalent cough, fever, sore throat, and headache.DiscussionOur results revealed that multiple independent SARS-CoV-2 introduction events had occurred through time, probably due to indigenous mobility, since the villages studied here are close to urban areas in MS. The mortality rate was slightly below of the estimation for the state in the period studied, which we believe could be related to the small number of samples evaluated, the underreporting of cases and deaths among this population, and the inconsistency of secondary data available for this study.ConclusionIn this study, we showed the circulation of multiple SARS-CoV-2 variants in this population, which should be isolated and protected as they belong to the most fragile group due to their socioeconomic and cultural disparities. We reinforce the need for constant genomic surveillance to monitor and prevent the spread of new emerging viruses and to better understand the viral dynamics in these populations, making it possible to direct specific actions