RESUMO Objetivo: Criar e validar um modelo de predição de choque séptico ou hipovolêmico a partir de variáveis de fácil obtenção coletadas na admissão de pacientes internados em uma unidade de terapia intensiva. Métodos: Estudo de modelagem preditiva com dados de coorte concorrente realizada em um hospital do interior do nordeste brasileiro. Foram incluídos pacientes com 18 anos ou mais sem uso de droga vasoativa no dia da admissão e que foram internados entre novembro de 2020 e julho de 2021. Foram testados os algoritmos de classificação do tipo Decision Tree, Random Forest, AdaBoost, Gradient Boosting e XGBoost para a construção do modelo. O método de validação utilizado foi o k-fold cross validation. As métricas de avaliação utilizadas foram recall, precisão e área sob a curva Receiver Operating Characteristic. Resultados: Foram utilizados 720 pacientes para criação e validação do modelo. Os modelos apresentaram alta capacidade preditiva com área sob a curva Receiver Operating Characteristic de 0,979; 0,999; 0,980; 0,998 e 1,00 para os algoritmos de Decision Tree, Random Forest, AdaBoost, Gradient Boosting e XGBoost, respectivamente. Conclusão: O modelo preditivo criado e validado apresentou elevada capacidade de predição do choque séptico e hipovolêmico desde o momento da admissão de pacientes na unidade de terapia intensiva. Objetivo intensiva Métodos brasileiro 1 202 2021 Tree Forest AdaBoost kfold k fold validation recall Resultados 72 0,979 0979 0 979 0,999 0999 999 0,980 0980 980 0998 998 0,99 100 00 1,0 respectivamente Conclusão 20 7 0,97 097 97 099 99 0,98 098 98 0,9 10 1, 2 09 9 0,

ABSTRACT Objective: To create and validate a model for predicting septic or hypovolemic shock from easily obtainable variables collected from patients at admission to an intensive care unit. Methods: A predictive modeling study with concurrent cohort data was conducted in a hospital in the interior of northeastern Brazil. Patients aged 18 years or older who were not using vasoactive drugs on the day of admission and were hospitalized from November 2020 to July 2021 were included. The Decision Tree, Random Forest, AdaBoost, Gradient Boosting and XGBoost classification algorithms were tested for use in building the model. The validation method used was k-fold cross validation. The evaluation metrics used were recall, precision and area under the Receiver Operating Characteristic curve. Results: A total of 720 patients were used to create and validate the model. The models showed high predictive capacity with areas under the Receiver Operating Characteristic curve of 0.979; 0.999; 0.980; 0.998 and 1.00 for the Decision Tree, Random Forest, AdaBoost, Gradient Boosting and XGBoost algorithms, respectively. Conclusion: The predictive model created and validated showed a high ability to predict septic and hypovolemic shock from the time of admission of patients to the intensive care unit. Objective unit Methods Brazil 1 202 included Tree Forest AdaBoost kfold k fold recall Results 72 0.979 0979 0 979 0.999 0999 999 0.980 0980 980 0998 998 0.99 100 00 1.0 respectively Conclusion 20 7 0.97 097 97 099 99 0.98 098 98 0.9 10 1. 2 09 9 0.

Adulterants in biodiesel/diesel blends modifies its physical and chemical properties. In this work, Fourier Transform Mid-Infrared spectrometry (FT-MIR) and multivariate control charts based on Net Analyte Signal (NAS) were used to monitor the quality of Crambe methyl biodiesel in relation to the biodiesel content and the presence of adulterants. The calibration model was constructed from the decomposition of the instrumental signals of the calibration samples into three vectors: NAS, interference and residual. From these vectors, three control charts were built: (i) NAS chart to monitor the analyte of interest (Crambe methyl biodiesel); (ii) Interference chart to monitor the data matrix (all components in diesel without the analyte of interest); and (iii) Residual chart to monitor any non-systematic variations. To validate the calibration model, other groups of B10, BX and B10 samples adulterated by direct addition of soybean oil and used fry oil in the range of 4.85-30.13% (v/v) were used. All samples prepared in-quality specifics were correctly classified as “in-quality control” samples, and other samples were correctly classified as “out-of-quality control” samples. Therefore, the methodology developed proved to be efficient in monitoring the quality of this fuel and it can be used by supervisory and quality control agencies.

Resumo A vigilância da concentração de flúor na água de abastecimento público visa garantir o equilíbrio entre o benefício (prevenção de cárie) e risco (fluorose dental) dos programas da fluoretação de água. O objetivo deste estudo foi verificar a precisão de dois métodos analíticos no monitoramento da concentração de flúor na água de abastecimento público de uma cidade brasileira. O checklist STROBE foi utilizado para auxiliar na condução desta pesquisa e relatar os resultados. Tratou-se de um estudo observacional analítico, de caráter prospectivo utilizando a água de abastecimento de Uberlândia, MG. Foram coletadas 126 amostras de água, em 21 pontos, durante seis meses seguidos e analisadas por meio do método com eletrodo íon seletivo (F-SIE) e por colorimetria com o SPADNS. A análise estatística foi realizada de maneira descritiva, em seguida, empregou-se o teste ANOVA e o teste t de Student para amostras pareadas. Os resultados mostraram que o método eletrométrico mostrou menor coeficiente de variação (12,3%) quando comparado o método colorimétrico (57,4%). Não foi observada variação significativa da concentração de fluoreto na água avaliada pelo F-ISE e SPADNS. Conclui-se que o método eletrométrico deve ser de primeira escolha para ser utilizado por laboratórios que monitoram a concentração de flúor nas águas de abastecimento público.

Abstract The surveillance of the concentration of fluoride in the public water supply aims to ensure the balance between the benefits (carie prevention) and risk (dental fluorosis) of water fluoridation programs. The aim of this study was to check the accuracy of two analytical methods for monitoring the concentration of fluoride in the public water supply of a Brazilian city. The STROBE checklist was used to aid the conduction of this study and report the results. It was an analytical, observational, and prospective study using the water supply of Uberlândia, MG, Brazil. We collected 126 water samples at 21 sites for six consecutive months and analyzed them using the fluoride ion selective electrode (F-ISE) method and colorimetry with SPADNS. The statistical analysis was performed descriptively and then the ANOVA and Student t-test for paired samples were applied. The results showed that the F-ISE method had a lower coefficient of variation (12.3%) than the SPADNS method (57.4%). There was no significant variation of the fluoride concentration in the water through the supply network evaluated either by F-ISE as SPADNS. We concluded that the electrometric method should be the first choice for use by laboratories that monitor fluoride concentration in the public supply water.

The production of methyl esters via transesterification reaction of triacylglycerides of macaúba and palm kernel oils, with subsequent atmospheric distillation and separation of six fractions of the produced biodiesel, corresponding to 60% of its initial volume, is reported. The composition in esters of the produced biodiesel, its fractions and remaining residue of the distillation was determined by gas chromatography. This analytical procedure has allowed to monitor the content in esters for each distilled fraction. The fractions richer in C8:0, C10:0, C12:0, C14:0 is intended to be used as an aviation fuel, in blends with the Jet-A1 biokerosene. The residues from the distillation with higher molecular weights than those corresponding to esters C16:0, C18:0 and C18:1 are destined to other combustion engines as any conventional biodiesel. For the biodiesel obtained from the macaúba kernel, this distillation led to an enrichment from 45.86% to up to 74.35% in the C12:0 ester. For the palm kernel biodiesel, the corresponding enrichment was from 66.76% up to 82.96%. Through this simple distillation, it was thus possible to effectively enrich, in C8:0 to C14:0 esters, the initial crude biofuel, with an efficiency of 30% for the macaúba and 11.5% for the palmiste biodiesel.

This paper presents methodologies for monitoring the quality of methyl cotton biodiesel in biodiesel/diesel blends using mid-infrared spectroscopy (MIR) and chemometrics tools. The first method relates to the construction of multivariate control charts with the aim of qualitatively monitoring the samples according to the Brazilian specification for biodiesel in the biodiesel/diesel blends (7.00 ± 0.5% v/v of biodiesel). The second concerns the construction of partial least squares (PLS) to determine the content of the biodiesel in the biodiesel/diesel blend. The PLS model was validated from multivariate figures of merit according to the guidelines of ASTM E1655-05 and IUPAC. The results from both methods were satisfactory for both qualitative and quantitative monitoring. Therefore, the proposed methodologies for monitoring the quality of biodiesel in biodiesel/diesel blends are fast, practical, economical and efficient and can be used by industries and service stations.

The degradation of vinasses in aqueous solution from ethanol industry has been investigated by electrochemical oxidation using a boron doped diamond electrode (BDD). Samples of vinasses were electrolyzed in medium of (0.1 mol L-1) Na2SO4 solutions at controlled potentials of +2.4, +3.0 and +4.0 V (vs. Ag/AgCl) and exhibited considerable reduction of total organic carbon. The cyclic voltammetry studies indicate that the vinasses are oxidized irreversibly over the BDD at 2.0 V (vs. Ag/AgCl) in diffusion controlled process. From the experimental results it is clear that the BDD electrode can be a valuable tool to the electrochemical degradation of vinasses in practical applications

Objetivou-se, com este trabalho, avaliar o efeito de diferentes sistemas de manejo do solo sobre os componentes de produção da soja cultivada solteira e em consórcio com B. decumbens, nos Tabuleiros Costeiros do Estado de Alagoas. Os tratamentos consistiram no cultivo da variedade de soja Monsoy 9350, nos sistemas preparo convencional do solo, cultivo mínimo e plantio direto. O delineamento experimental utilizado foi o em blocos casualizados, com parcelas subdivididas (com e sem B. decumbens), e quatro repetições. As variáveis analisadas foram: 1) cultura da soja: determinação dos estágios fenológicos, composição química das plantas, estande de plantas, diâmetro do colmo, altura de plantas, altura de inserção da primeira vagem, número de vagens por planta, número de grãos por vagem, número de grãos por planta, massa de 1.000 grãos e produtividade; e 2) B. decumbens: composição química das plantas, além do acúmulo de matéria seca, em cinco épocas de amostragens. Os sistemas de manejo do solo influenciaram o estande de plantas e a concentração de P, Cu, Fe e Zn, na soja, além do S, na Brachiaria decumbens. O sistema plantio direto apresentou maior produtividade de grãos e produção de fitomassa de B. decumbens, nas condições edafoclimáticas de Rio Largo (AL).

The aim of this study was to evaluate the effects of different soil management systems on the soybean yield components intercropped or not with Brachiaria decumbens, in the coastal plateau of the Alagoas State, Brazil. For that, the 9350 Monsoy soybean was cultivated under conventional tillage, minimum tillage, and no-tillage. The experiment was carried out by using a split-plot randomized blocks design (with and without B. decumbens) and four replications. The variables analyzed were: 1) soybean: determination of phenological stages, chemical composition of plants, stand of plants, stem diameter, plant height, first pod insertion height, number of grains per pod, number of pods, number of grains per plant, mass of 1,000 grains, and yield; and 2) B. decumbens: chemical composition of plants and accumulation of dry matter, in five different sampling times. The soil management systems influenced the stand of plants and the concentration of P, Cu, Fe, and Zn, in soybean, besides S, in B. decumbens. The no-tillage system showed higher grain and biomass yield for B. decumbens, under the edaphoclimatic conditions of Rio Largo, Alagoas State, Brazil.

O objetivo deste trabalho foi determinar o coeficiente de expansão térmica do biodiesel a partir de dados experimentais de densidade em função da temperatura. Para tanto, foram utilizados alguns fundamentos da termodinâmica. O valor obtido para o coeficiente de expansão térmica após regressão linear para o biodiesel foi de 8,49 × 10-4 ºC-1, com um coeficiente de correlação igual a 0,9978.

The purpose of this study was to determine the coefficient of thermal expansion of the biodiesel from the experimental data of density as a function of temperature. For this, we used some fundamentals of thermodynamics. The value obtained for the coefficient of thermal expansion after the linear regression for biodiesel was 8.49 × 10-4 ° C-1, with a correlation coefficient equal to 0.9978.