The objective of the present work was to apply self-organizing feature maps (SOFM) and multilayer perceptron (MLP) to evaluate the protective capacity of tert-butylhydroquinone (TBHQ), butylhydroxyanisole (BHA), and butylhydroxytoluene (BHT) antioxidants against the biodiesel oxidation reaction. For this, the antioxidant concentration and the biodiesel compliance parameters were used as continuous input variables and the type of antioxidant as a categorical. The SOFM proved to be an adequate tool for the classification of biodiesel samples containing antioxidants. The performance of the 5 most active networks of the model ranged from 89 to 99% for training, testing, and validation with an error below 1.42 × 10-4. Statistical tests applied to validate the model showed no significant difference between predicted and experimental values. The global sensitivity analysis showed that the relative protection factor (RPF) contributed with 34.89%, the antioxidant with 31.49%, the induction period with 10.69%, the water content with 6.00%, and the others all together with 16.93% in the construction of the regression models by MLP.

The simultaneous diffusion of inorganic components in the olive pulp in wet brine was modeled based on Fick’s generalized 2nd Law and simulated using the finite element method. The main and crossed diffusion coefficients, the film coefficient and the Biot number were determined, with the application of the simplex optimization method, through the minimization of the percentage errors. The errors between the simulated and experimental data were 5.35% for NaCl and 4.77% for KCl and the adjusted main diffusion coefficients were 0.4358 × 10-12 m2 s-1 for NaCl and 0.5408 × 10-12 m2 s-1 for KCl. The system developed to simulate diffusion allows the control and modulation of the salts content that diffuses through the olive pulp.

This work compares the anticorrosive properties of DC electrodeposited CuCoNi, CuCo, and CuNi alloy coatings in a NaCl 0.5 mol L-1 solution. The results showed that j and the bath composition influenced the chemical, morphological, and electrochemical characteristics of the alloy coatings. Among all the studied coatings, the CuCo, CuNi, and CuCoNi ones produced at j = 10 A m-2, j = 60 A m-2, and j = 25 A m-2, respectively, showed the best anticorrosive performances in the saline medium, exhibiting charge transfer resistances (Rtc) higher than 2000 Ω cm2 and an electrical double layer capacitances (Cdl) lower than 8 X10-4 F cm-2. These results agree with the compact morphologies and smaller grain sizes presented by these coatings. Therefore, the anticorrosive properties of the coatings cannot be related only to the less noble metal(s) contents in the alloy but also to their morphologies.

Olive samples were subjected to the salting process in brine containing 1196 mol m−3 of NaCl and 402 mol m−3 of KCl. Samples were collected during 60 h and salt concentration values were determined. With the finite element method (FEM) and the minimization of the errors percentage between the simulated and experimental values, the mass transfer coefficients in the film (hm) were obtained, being 1.0072 × 10−8 and 1.2499 × 10−8 for NaCl and KCl, respectively. The salts concentration at the olive/brine interface was simulated by FEM and analyzed via SOFM. A network with 4 × 4 topology and 10000 training epochs was used. It was observed that the influence of the stationary film formed on the surface of the olives during the salting process depends on the position, the salt involved in the diffusion and that the concentration of the salts, at each point, varies according to the immersion time.

RESUMEN Introducción: Es de práctica habitual la internación durante 24 h en los pacientes (P) intervenidos con una angioplastia coronaria (ATC) programada. Experiencias previas proponen el alta post ATC en el mismo día en P seleccionados. Material y métodos: Estudio prospectivo, aleatorizado, controlado, simple ciego. Se incluyeron P de 18 a 75 años candidatos a una ATC programada por acceso radial, con posibilidad de acceder al sistema de emergencias en menos de 40 minutos. Se excluyeron los P con fracción de eyección ventricular izquierda < 30%, Creatinina > 1,5 mg/dL, insuficiencia cardíaca, enfermedad pulmonar obstructiva crónica, diabetes descompensada, o anatomía coronaria muy compleja. Se dividió a la población en dos grupos (G). G 1: alta en 6 horas. G2: alta al día siguiente. Punto final primario: muerte o necesidad de rehospitalización dentro de las 24 h de realizado el procedimiento. Se realizó seguimiento telefónico la noche del procedimiento y a la mañana siguiente, presencial a las 48 h, y telefónico al mes, seis meses y un año. Resultados: Se adjudicaron aleatoriamente 80 P. Seis P (7,5%) presentaron criterios de exclusión durante el procedimiento. No se produjo ninguna muerte ni evento cardiovascular mayor en ninguno de ambos grupos. Al año de seguimiento se detectó 3,75% de reestenosis intra stent. Se detectó elevación de troponina en 20 P (25%) de los cuales 4 habían sido excluidos por complicaciones durante la ATC. En los restantes 16, la elevación de la troponina no tuvo repercusión clínica. Conclusión: En una población de pacientes entre 55 y 75 años, en su mayoría de género masculino, con alta prevalencia de infarto de miocardio previo, y depresión de la función ventricular, pudo realizarse una angioplastia programada por acceso radial con alta en 6 horas, con un adecuado margen de seguridad.

ABSTRACT Background: 24-hour hospitalization is common practice in patients (P) who underwent scheduled coronary angioplasty (PCI). Previous experiences propose same-day discharge in selected P. Methods: Prospective, comparative, randomized, single-blind study. P aged 18 to 75 years were included as candidates for a scheduled radial-access PCI with the possibility of accessing the emergency system in less than 40 minutes. P with left ventricular ejection fraction <30%, creatinine >1.5 mg/dL, heart failure, chronic obstructive pulmonary disease, decompensated diabetes or very complex coronary anatomy were excluded. The population was divided in two groups (G). G 1: same-day discharge in 6 hours. G2: discharge the next day. Primary endpoint: death or need for rehospitalization within 24 hours of the procedure. Follow-up was carried out by phone the night of the procedure and the next morning, in person at 48 hours, and by telephone after a month, six months and a year. Continuous variables were expressed as median and their respective interquartile range, and qualitative variables as percentages. Results: 80 P were randomized. Six P (7.5%) presented exclusion criteria during the procedure. There were no deaths or major cardiovascular events in either groups. At one year of follow-up, 3.75% of in-stent restenosis was detected. Troponin elevation was detected in 20 P (25%); 4 were P excluded due to complications during PCI, in the remaining 16 it had no clinical repercussion. Conclusion: In a population of patients between 55 and 75 years old, mostly male, with a high prevalence of previous myocardial infarction, and ventricular function depression, a scheduled radial-access PCI could be performed with same day discharge in 6 hours, with an adequate safety margin.

Biodiesel is capable of replacing diesel because it has similar physicochemical properties, but this biofuel is susceptible to oxidation, which makes the application of antioxidant substances necessary. For this study, alcoholic extracts of senna leaves, hibiscus flowers, and blackberry were used. Biodiesel samples were submitted to physicochemical analysis to evaluate interference in the volume of these alcoholic extracts with antioxidant properties. The data obtained were processed using the neural network of the multilayer perceptron type (MLP). For the network’s training, 200 epochs were used. The samples were randomly divided into three groups, with 70% used for training, 15% for testing, and 15% for validation. The type of extract was considered as a categorical variable, the extract volume as a target variable, and the other ones as input variables. Among the 200 networks trained, with 5 to 20 hidden layers, the 5 with the best performance were highlighted. The Tukey test applied to the means showed no significant difference at the 5% level, between the value of the added volume and the means value predicted by the networks. The sensitive analysis showed that the most important input variable for the construction of the model was the type of extract.

Sodium chloride is used in the cheese salting process as it promotes sensory changes and food preservation. However, in excess can cause hypertension problems, and for this reason, it has been partially replaced by potassium chloride. In the present work, Prato cheese was subjected to joint diffusion of NaCl and KCl by immersion in static and stirred brine. The salt concentration values on the cheese surface were determined as a function of time. They were tabulated and presented to the self-organizing map (SOM)-type neural networks and the multilayer perceptron (MLP) for analysis and modeling of the film formed on the surface of the cheese during static and dynamic salting. The SOM network showed that the behavior of the diffusive process, on the surface of the cheese, depends on the analyzed position and that the points in which occupy similar positions, concerning the distance from the edge, have similar behavior. Regression models for NaCl and KCl were significant at the 5% level and can be used for predictive purposes.

The influence of the film formed during the salting of champignon mushrooms with brine containing NaCl and KCl was modeled using the finite elements method (FEM). It was verified that the film formed on the mushroom surface had a greater influence in the static salting since the diffusion of the ions was 7.5-fold smaller in this system than in the stirred salting. The application of self-organizing maps showed that the ions diffusion along the surface of the solid presented a heterogeneous occurrence and depended on the region for both static and stirred salting. A direct relation was observed among the mushroom surface morphology, the salts diffusion behavior, and the film formation. In addition, the film was not completely extinguished in the stirred system, although it has a minimal influence as the film formation is also dependent on the biosolid surface.

The NaCl and KCl diffusion in the film formed on the cheese surface during salting was simulated by the finite element method. The time and salts concentration values on the cheese surface were determined, tabulated, and presented to the multilayer perceptron neural network (MLP) for the regression modeling. The samples were divided into 70, 15 and 15% for training, testing, and validation, respectively. The networks with the best performance showed 5 to 12 hidden layers. The Tukey’s test showed that there was no significant difference, at the 5% level, between the time value used and the mean value modeled for training, testing, and validation for the NaCl. For the KCl, a significant difference was observed only for 2 training samples and 1 test sample. Sensitivity analysis showed that the discrete variable Z, which represents the static and dynamic systems, was the most important in the models’ construction.

Abstract Background Agriculture in South America (SA) had a great expansion in the last decades and weed control changed accordingly with region and crop practices. Objective The objective of this review is to present the history of herbicide use and discuss the main changes in weed management in SA. Methods Herbicide use quantities were obtained from official institutions and commercial organizations in Argentina, Brazil, Chile, Paraguay and Uruguay. Data were summarized per active ingredient, herbicide mode of action or crop. The evolution of the cultivated area of the main crops in each country, and the crop and weed management associated to it were considered to discuss the importance and the consequences of the main herbicides used. Results In 2019 the most used herbicides in Brazil were glyphosate, 2,4-D, atrazine, paraquat and diuron representing 62, 15, 7, 5 and 2% of the total amount used. In Argentina, the increasing selection of herbicide resistant populations (4 cases/year), resulted in utilization of older chemistries. Weed control in Uruguay is traditionally benefited from crop/pasture rotations but recently is also facing problems of continuous cropping systems. Agriculture in Chile is more diverse, but similar patterns and problems of herbicide use are present. Conclusions Intensification of agriculture, no-tillage, glyphosate resistant crops, and herbicide resistant weeds were the most important drivers of herbicide use changes in SA. Integrated weed management is unpostponable to provide sustainable increasing food production in SA.

Resumo Fundamento: O tabagismo geralmente está associado à hipertensão e pode modificar a resposta vasoconstritora. Objetivo: O presente estudo teve como objetivo analisar e comparar a interação do tabagismo passivo e hipertensão sobre os efeitos da epinefrina e felipressina na pressão arterial após injeção intravascular. Métodos: Ratos Wistar machos de 45 dias tiveram a artéria renal principal esquerda parcialmente obstruída e o rim direito removido (modelo 1K1C). Os ratos foram colocados na câmara para exposição ao tabagismo passivo (10 cigarros) durante 10 minutos (6 dias por semana). Ratos hipertensos receberam atenolol (90 mg/kg/dia) por gavagem durante duas semanas. A resposta hipotensora e hipertensiva, a duração da resposta e a frequência cardíaca foram registradas a partir da medida dos valores diretos da pressão arterial. O nível de significância foi de 5%. Resultados: O tabagismo passivo aumentou a resposta hipertensiva máxima à epinefrina em ratos normotensos e ratos 1K1C tratados com atenolol e à felipressina apenas em ratos 1K1C tratados com atenolol; também reduziu a resposta hipotensiva à epinefrina. A epinefrina aumentou a frequência cardíaca em ratos fumantes passivos ou não-fumantes, normotensos e hipertensos. Comparando os dois vasoconstritores, a epinefrina apresentou maior resposta hipertensiva em fumantes normotensos, ratos 1K1C fumantes e não fumantes tratados com atenolol. No entanto, em ratos normotensos e não fumantes, a felipressina apresentou um efeito hipertensivo maior e mais prolongado. Conclusões: Nossos resultados sugerem que o tabagismo passivo pode reduzir a vasodilatação da epinefrina e aumentar a resposta hipertensiva quando comparado à felipressina. Portanto, a felipressina pode ser segura para pacientes hipertensos, com o objetivo de evitar a interação entre taquicardia e atenolol, mas para pacientes normotensos e não-fumantes, a epinefrina pode ser mais segura que a felipressina.

Abstract Background: Cigarette smoking is usually associated with hypertension and may modify vasoconstrictor response. Objective: The present study aimed to analyze and compare the interaction of passive cigarette smoking and hypertension on epinephrine and felypressin blood pressure effects after intravascular injection. Method: 45-day male Wistar rats had the main left renal artery partially constricted and the right kidney removed (1K1C model). Rats were placed in the chamber for exposition to passive cigarette smoking (10 cigarettes) during 10 min (6 days a week). Hypertensive rats received atenolol (90 mg/kg/day) by gavage for two weeks. Hypotensive and hypertensive response, response duration and heart rate were recorded from direct blood pressure values. The significance level was 5%. Results: Passive cigarette smoking increased maximal hypertensive response to epinephrine in normotensive and 1K1C-atenolol treated rats and to felypressin only in 1K1C-atenolol treated rats; it also reduced epinephrine hypotensive response. Epinephrine increased heart rate in normotensive and hypertensive passive smokers or non-smoker rats. Comparing the two vasoconstrictors, epinephrine showed greater hypertensive response in normotensive smokers, 1K1C-atenolol treated smokers and non-smokers. However, in normotensive-nonsmoker rats, felypressin showed a greater and longer hypertensive effect. Conclusions: Our results suggest that passive cigarette smoking may reduce epinephrine vasodilation and increase hypertensive response when compared to felypressin. Therefore, felypressin may be safe for hypertensive patients to avoid tachycardia and atenolol interaction, but for normotensive and non-smoker patients, epinephrine may be safer than felypressin.

The purpose of this research was to evaluate the influence of metallic alloys and copper in the degradation of biodiesel in mixture with blackberry extract. Biodiesel is formed by unsaturated esters highly susceptible to the oxidation reaction. The initial induction period (IP) of the control sample was 9.53 h and, after 208 days, the IP reduced to 5.74 h. However, with the addition of the antioxidant, the final IP was 6.27 h. The assays involving carbon steel, stainless steel, silver steel and copper showed final IP of 3.78, 4.43, 1.59 and 0.09 h, respectively. This behavior indicates that the reaction was catalyzed in the presence of metal. The addition of the blackberries extract favored the increase of the induction period and the decrease of the reaction rate constant values, aside from the carbon steel that presented a final IP of 1.22 h. The highest rate constant was 7.41 h obtained for biodiesel in contact with copper, as well as the highest IP. The acid number ranged from 0.34 to 0.60 mgKOH g-1. It was possible to observe in the oxidation reactions the presence of the linearity deviation proposed by Arrhenius.

Abstract Time between seed germination and an autotrophic plant is a critical stage. During this period the seedling is susceptible to competition with weeds and adverse soil and climate change conditions due to its reduced root system and scarce leaf area, as in the case of maize (Zea mays L.). The use of biochemical agents as coating on seeds that promote a greater root development in early stages favors a good initial development of the seedling. This study aimed to evaluate the effect of coatings with chitosan (30 g L-1), sodium alginate (50 g L-1), salicylic acid (1x10-3 M) and fertilizers equivalent to a dose of N-P2O5-K2O: 26.7-7.5-13.3 kg ha-1 in the emergence, root development, and absorption of water and nutrients in two maize genetic lines with contrasting root development. The hypothesis was that the coating of maizeseeds with one or more of these materials favors the water and nutritional status of the seedling, which stimulates an efficient emergence, increases the root biomass and the absorption of water and nutrients. The experimental design was completely randomized with a 2x6 factorial arrangement (2 maize lines, 6 coatings) with two controls (uncoated seed). The experimental units were pots and the comparison of means was performed with the LSD test (p≤0.05). Seeds were covered by the ionic gelation technique sowed in tezontle and irrigated with the Steiner nutrient solution without macronutrients in the greenhouse. The biomass and nutritional concentration of the seedlings were evaluated 30 and 50 d after sowing (DAS). The emergence of plants decreased as a result of the coatings: chitosan (40 %) and sodium alginate (14 %). Fertilizers and salicylic acid reduced biomass and root length (30 DAS). There was no consistent effect of coatings on nutrient concentration in maize plants.

Resumen El tiempo entre la germinación de la semilla y una planta autótrofa es una etapa crítica. Durante este periodo la plántula es susceptible a la competencia con malezas y condiciones edafoclimáticas adversas debido a su reducido sistema radicular y escasa área foliar, como el caso del maíz (Zea mays L.). El uso de agentes bioquímicos como recubrimiento en semillas que promuevan un mayor desarrollo radical en etapas tempranas favorece un buen desarrollo inicial de plántula. Este estudio tuvo como objetivo evaluar el efecto de recubrimientos con quitosano (30 g L-1), alginato de sodio (50 g L-1), ácido salicílico (1x10-3 M) y fertilizantes equivalente a una dosis de N-P2O5-K2O: 26.7-7.5-13.3 kg ha-1, en la emergencia, desarrollo radical, y absorción de agua y nutrimentos, en dos líneas genéticas de maíz con desarrollo radical contrastante. La hipótesis fue que el recubrimiento de semillas con uno o más de estos materiales favorece el estatus hídrico y nutrimental de la plántula, que estimula una eficiente emergencia e incrementa la biomasa radical, la absorción de agua y nutrimentos en maíz. El diseño experimental fue completamente al azar con un arreglo factorial 2x6 (2 líneas genéticas de maíz, 6 recubrimientos) con dos testigos (semilla sin recubrimiento). Las unidades experimentales fueron macetas y la comparación de medias se realizó con la prueba LSD (p≤0.05). Las semillas fueron recubiertas mediante la técnica de gelificación iónica, sembradas en tezontle y regadas con solución nutritiva Steiner sin macronutrimentos en invernadero. La biomasa y concentración nutrimental de las plántulas se evaluaron 30 y 50 d después de la siembra (DDS). La emergencia de las plantas disminuyó por los recubrimientos: quitosano (40 %) y alginato de sodio (14 %). Los fertilizantes y ácido salicílico redujeron la biomasa y longitud radical (30 DDS). No hubo un efecto consistente de los recubrimientos sobre la concentración nutrimental en las plantas de maíz.

This paper aims the morphological and structural characterization of ceramic membranes of mullite and their application in the removal of Escherichia coli. A complex irregular structure presented by the pores of the membrane was verified by scanning electron microscopy (SEM). The average pore size and distribution were determined by mercury intrusion porosimetry. The average pore size of the material presented was 0,39 µm. Microfiltration tests resulted in a protein retention of 46, 76 and 89% for trypsin (TR), egg albumin (EA) and bovine serum albumin (BSA), proving the efficiency of the membrane microfiltration tests for molecular weight of 69 kDa. The application of the membranes on the retention of gram-negative bacterium E. coliresulted in a 66% efficiency at a pressure of 200 kPa and a 98% efficiency when applied a pressure of 50 kPa. Therefore, the use of mullite membranes show limited efficiency towards bacteria retention. Nevertheless, they present fluxes similar to other materials proposed in the literature.

Eletrocatalisadores Pd/C, Au/C e PdAu/C com diferentes razões atômicas foram preparados utilizando-se irradiação por feixe de elétrons e testados na oxidação eletroquímica de glicerol em uma célula alcalina a glicerol direto (ADGFC). Os difratogramas de raios X (XRD) evidenciaram a presença de fases ricas em Pd (fcc) e Au (fcc). As análises de voltametria cíclica (CV) e cronoamperometria indicaram que o eletrocatalisador com razão atômica 50:50 demonstrou atividade superior para a oxidação eletroquímica do glicerol a temperatura ambiente. As análises de infravermelho com transformada de Fourier no modo de refletância total atenuada (ATR-FTIR) in situ identificaram como principais produtos da oxidação eletroquímica do glicerol: 1,3-diidroxi-2-propanona, gliceraldeído e glicolato. Os experimentos em célula unitária foram realizados entre 50 e 90 ºC e foi constatado que o melhor desempenho aconteceu a 80 ºC.

Pd/C, Au/C and PdAu/C electrocatalysts with different atomic ratios prepared using electron beam irradiation were tested for glycerol electrooxidation in single alkaline direct glycerol fuel cell (ADGFC). X-ray diffractograms (XRD) of PdAu/C electrocatalysts showed the presence of Pd (fcc) and Au (fcc) phases. Cyclic voltammetry (CV) and chronoamperometry showed that PdAu/C electrocatalyst with Pd:Au atomic ratio of 50:50 demonstrated superior activity for glycerol electrooxidation, at room temperature. In situ Fourier transform infrared spectroscopy by attenuated total reflectance (ATR-FTIR) experiments were performed for the electrocatalysts, identifying oxalate, glycerate ion, 1,3-dihydroxy-2-propanone, glyceraldehyde and glycolate as products of glycerol electrooxidation. Experiments with single ADGFC were carried out from 50 to 90 ºC, using Pd/C electrocatalyst; the best performance was obtained at 80 ºC.