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Reservoirs often play an important role in mitigating water supply problems. However, the implications of climate change are not always considered in reservoir planning and management. This study aimed to address this challenge in the Alto Sabor watershed, northeast Portugal. The study analysed whether or not the shortage of water supply can be effectively addressed through the construction of a new reservoir (two-reservoir system) by considering future climate projections. The hydrological model Soil and Water Assessment Tool (SWAT) was calibrated and validated against daily-observed discharge and reservoir volume, with a good agreement between model predictions and observations. Outputs from four General Circulation Models (GCM) for two scenarios (RCP 4.5 and 8.5) were statistically downscaled and bias-corrected with ground observations. A general increase in temperature is expected in the future while the change in precipitation is more uncertain as per the differences among climatic models. In general, annual precipitation would slightly decrease while seasonal changes would be more significant, with more precipitation in winter and much less in spring and summer. SWAT simulations suggest that the existence of two-reservoir will better solve the water supply problems under current climate conditions compared to a single-reservoir system. However in the future, the reliability of this solution will decrease, especially due to the variability of projections from the different climatic models. The solution to water supply problems in this region, adopted taking only present-day climate into account, will likely be inefficient for water supply management under future climate conditions.

This work focuses on the dynamic monitoring behaviour of concrete dams, with a specific emphasis on the Baixo Sabor dam as a case study. The main objective of the dynamic monitoring is to continuously observe the dam’s behaviour, ensuring it remains within expected patterns and issuing alerts if deviations occur. The monitoring process relies on on-site instruments and behaviour models that use pattern recognition, thereby avoiding explicit dependence on mechanical principles. The undertaken work aimed to develop, calibrate, and compare statistical and machine learning models to aid in interpreting the observed dynamic behaviour of a concrete dam. The methodology included several key steps: operational modal analysis of acceleration time series, characterisation of the temporal evolution of observed magnitudes and influential environmental and operational variables, construction and calibration of predictive models using both statistical and machine learning methods, and the comparison of their effectiveness. Both Multiple Linear Regression (MLR) and Multilayer Perceptron Neural Network (MLP-NN) models were developed and tested. This work emphasised the development of several MLP-NN architectures. MLP-NN models with one and two hidden layers, and with one or more outputs in the output layer, were performed. The aim of this work is to assess the performance of MLP-NN models with different numbers of units in the output layer, in order to understand the advantages and disadvantages of having multiple models that characterise the observed behaviour of a single quantity or a single MLP-NN model that simultaneously learns and characterises the observed behaviour for multiple quantities. The results showed that while both MLR and MLP-NN models effectively captured and predicted the dam’s behaviour, the neural network slightly outperformed the regression model in prediction accuracy. However, the linear regression model is easier to interpret. In conclusion, both methods of linear regression and neural network models are suitable for the analysis and interpretation of monitored dynamic behaviour, but there are advantages in adopting a single model that considers all quantities simultaneously. For large-scale projects like the Baixo Sabor dam, Multilayer Perceptron Neural Networks offer significant advantages in handling intricate data relationships, thus providing better insights into the dam’s dynamic behaviour.

Abstract The goal of this study was to analyze cytotoxicity, genotoxicity and mutagenicity to bone marrow cells of mice of nature identical synthetic flavorings, passion fruit and strawberry, and artificial synthetic flavorings, vanilla, chocolate, tutti-frutti and cookie, at doses 0.5; 1.0; 2.0; 5.0 and 10.0 mL/kg. The additives were given to the animals by gavage in a single daily application for seven days. Data were subjected to analysis of variance (ANOVA) followed by post Tukey’s post hoc test, p <0.05. Animals treated with 2.0; 5.0 and 10.0 mL/Kg of flavorings chocolate, strawberry and cookie, and 5.0 and 10.0 mL/Kg of flavorings vanilla and passion fruit died on the fifth and sixth day of the experiment, respectively. The doses 0.5 and 1.0 mL/Kg of the six additives significantly reduced erythropoiesis in the examined tissue. Also, treatments 0.5 and 1.0 mL/Kg of chocolate, and 1.0 mL/Kg of strawberry and biscuit induced the formation of micronuclei in the bone marrow erythrocytes, at a significant frequency. Therefore, under the study conditions, the six microingredients analyzed were cytotoxic and genotoxic, and additives strawberry, chocolate and cookie were also mutagenic in at least one of the evaluated doses. Resumo Os aromatizantes são essenciais para a indústria na confecção de alimentos industrializados. Porém, pouco se sabe sobre o potencial tóxico desses microingredientes alimentares. Dessa forma, objetivou-se neste trabalho analisar, em células de medula óssea de camundongos, a citotoxicidade, genotoxicidade e mutagenicidade de aromatizantes alimentares sintéticos idênticos ao natural, de maracujá e morango, e artificiais, de baunilha, chocolate, tutti-frutti e biscoito, nas doses 0,5; 1,0; 2,0; 5,0 e 10,0 mL/Kg. Os aditivos foram administrados aos animais via gavagem em aplicação diária única durante sete dias. Os dados obtidos foram submetidos ao procedimento estatístico ANOVA com pós teste de Tukey, com p < 0.05. Os animais tratados com 2,0; 5,0 e 10,0 mL/Kg dos aromatizantes de chocolate, morango e biscoito, e 5,0 e 10,0 mL/Kg dos aromatizantes de baunilha e maracujá vieram a óbito no quinto e sexto dia de experimento, respectivamente. As doses 0,5 e 1,0 mL/Kg dos seis aditivos reduziram significativamente a eritropoiese do tecido analisado. Ainda, os tratamentos 0,5 e 1,0 mL/kg de chocolate, e 1,0 mL/Kg de morango e biscoito induziram a formação de micronúcleos aos eritrócitos de medula em frequência significante. Portanto, nas condições de estudo estabelecidas, os seis microingredientes analisados foram citotóxico e genotóxicos, e os aditivos de morango, chocolate e biscoito também foram mutagênicos em pelo menos uma das doses avaliadas.

This study aimed to evaluate the taste profile of traditional Chinese Fuliji Red-cooked Chicken (FRCC) in five processing steps, consisting of raw, frying, stewing, vacuum-packaging and sterilization by measuring sodium chloride (NaCl), sugar, free amino acids (FAAs) and nucleotides, and by subjecting all the samples to an electronic tongue. Results showed that NaCl, 5ʹ-Inosine monophosphate (5ʹ-IMP), lysine (Lys), methionine (Met) and cysteine (Cys), which had relatively high contents, might be main taste compounds in FRCC. The NaCl content increased gradually from the frying to the sterilization step (P < 0.05) and had the highest value (2.52%) during the sterilization step. Total sugar content and flavor nucleotides were the highest during the frying step and decreased during all the other steps. Compared to raw chicken, 5ʹ-IMP increased significantly in frying and stewing steps (P < 0.05), followed by decreases during the vacuum-packing and the sterilization steps. It was indicated that frying and stewing were the most important processing steps for the taste development of FRCC. Vacuum-packaging and sterilization had no negative effects on the sensory quality of chicken meat. In addition, the electronic tongue was able to satisfactorily distinguish the taste formation of chicken meat, among the five processing steps.

Both the magnetic field treatment and the microwave treatment can affect the concentration of aroma compounds in liquor, but there are few researches on the composite treatment that combining the two. In this study, the effects of separate pulsed magnetic field (PMF), microwave field, and PMF-microwave composite treatment on Chinese soy-sauce flavor liquor were investigated. The concentration changes of various aroma compounds in liquor were analyzed by gas chromatograph, and the change of water-ethanol association structure in liquor was analyzed by proton nuclear magnetic resonance spectroscopy. Sensory evaluation of liquor subjected to different processes was carried out. The results showed that the sensory characteristic of liquor after composite treatment was improved, and the change of aroma compounds is close to that in traditional aging. The PMF treatment can significantly improve the taste of liquor. The results prove that the PMF-microwave composite treatment is a potential artificial aging method.

Most gravity-filtration coffee preparation methods constitute good alternatives for obtaining coffee with varying acidity, bitterness, and bodies. The present study identifies the composition of compounds with antioxidant capacities and cup profiles for coffee beverages prepared using eight gravity-filtration methods. UV-visible spectrophotometry and high-performance liquid chromatography  quantified antioxidants, hydroxycinnamic acids, and antioxidant activity. A qualitative descriptive analysis was performed using an expert panel to establish the sensory quality. The methods that yielded the highest total phenol and flavonoid concentrations were Chemex, Siphon, and Silvertone. The Silvertone, Siphon, and Neapolitan methods had the most condensed tannin content. The maximum hydroxycinnamic acid content was found with the Siphon and Neapolitan methods. Antioxidant capacity was evaluated by the ABTS (antioxidant capacity of the cationic radical 2,2-Azino-bis-3-ethylbenzthiazoline-6-sulfonic acid), ORAC (Oxygen Radical Absorption Capacity), and FRAP (Ferric Reducing Antioxidant Power) methods and found to be the highest with the Silvertone, Siphon, and Neapolitan methods. The preparation methods with the highest sensorial scores were Silvertone and Chemex, while the lowest sensorial acceptance level was found with the Cloth filter method. Beverages made with the Kalita and Drip methods showed the lowest antioxidant compound expressions. The most predominant hydroxycinnamic acid was chlorogenic acid in the eight preparations studied. We thus recommend that coffee be consumed following preparation with the Silvertone, Siphon, or Neapolitan methods to increase antioxidant consumption in the diet. Should the consumer prefer bitter notes, these may be found with the Silvertone preparation method; otherwise, one may enjoy acidic notes in coffee beverages with the Siphon and Neapolitan methods.

Fruit flavor is a result of a complex mixture of numerous compounds. The formation of these compounds is closely correlated with the metabolic changes occurring during fruit maturation. Here, we describe the use of DNA microarrays and appropriate statistical analyses to dissect a complex developmental process. In doing so, we have identified a novel strawberry alcohol acyltransferase (SAAT) gene that plays a crucial role in flavor biogenesis in ripening fruit. Volatile esters are quantitatively and qualitatively the most important compounds providing fruity odors. Biochemical evidence for involvement of the SAAT gene in formation of fruity esters is provided by characterizing the recombinant protein expressed in Escherichia coli. The SAAT enzyme showed maximum activity with aliphatic medium-chain alcohols, whose corresponding esters are major components of strawberry volatiles. The enzyme was capable of utilizing short- and medium-chain, branched, and aromatic acyl-CoA molecules as cosubstrates. The results suggest that the formation of volatile esters in fruit is subject to the availability of acyl-CoA molecules and alcohol substrates and is dictated by the temporal expression pattern of the SAAT gene(s) and substrate specificity of the SAAT enzyme(s).

The sensory characteristics of Maillard reaction products from chicken protein hydrolysates (MRP-CPHs) at different degrees of hydrolysis (DH) were evaluated using descriptive sensory analysis. Five characteristics (boiled chicken flavor, umami, mouthfulness, continuity and overall acceptance) of the MRP-CPHs were evaluated. In addition, the changes in free amino acid contents and molecular weight distribution of chicken protein hydrolysates (CPHs) were also determined. The results showed that the sensory attributes were affected by DH of the CPHs, there was a distinct difference among the MRP-CPHs of almost all sensory attributes. The Maillard reaction product with a hydrolysis time of 3 h showed the strongest in the mouthfulness, boiled chicken flavor, and overall acceptance. These results indicated that the CPHs with a DH range from 15.80% to 18.64% (hydrolysis time range from 3 to 6 h) might be a desirable precursor for the production of chicken flavor in the food industry.

El dramático aumento de la prevalencia e incidencia de la obesidad sugiere que factores ambientales y cambios en el estilo de vida contribuyen de forma importante a su tendencia epidémica. En humanos, se han reportado diferencias interindividuales en los umbrales de detección y preferencia del sabor dulce, lo que podría afectar la ingesta habitual de azúcares, y por ende al estado nutricional. Objetivo: El presente estudio busca determinar la relación entre el estado nutricional y la preferencia al sabor dulce en la comunidad de un establecimiento de educación superior. Método: Muestra fue constituida por estudiantes, funcionarios y docentes, entre 18 y 60 años, pertenecientes a la Universidad Mayor, Sede Temuco. Para determinar preferencia al sabor dulce se empleó prueba organoléptica que mide grado de satisfacción frente a solución dulce, junto a ello se realizaron mediciones de peso y talla para determinar el Índice de Masa Corporal. Resultados: Muestra final comprendió de 319 personas, de las cuales un 30,1% fueron hombres y 69,9% mujeres. No se observaron diferencias significativas en la preferencia hacia las soluciones con mayor concentración de sacarosa según el estado nutricional. Sin embargo, el modelo predictivo desarrollado arrojó que hombres prefieren las soluciones con mayor concentración de azúcar independiente de la edad y estado nutricional. Conclusiones: Es necesario desarrollar nuevos estudios que permitan aclarar si la preferencia al sabor dulce favorece el desarrollo de obesidad y sobrepeso, o si es la composición nutricional de los alimentos procesados o ultraprocesados, lo que está teniendo un mayor impacto negativo en el estado nutricional de la población. The dramatic increase in the prevalence and incidence of obesity seems to suggest that environmental factors and lifestyle changes are contributing significantly to the epidemic trend of this pathology. In humans, inter-individual differences in the thresholds of preference of sweet taste have been reported, which could affect habitual sugar intake, and therefore the nutritional status. Objective: The present study seeks to determine the relationship between nutritional status and the preference of sweet taste in the population of a higher education establishment. Method: Sample was constituted by students, officials and teachers between 18 and 60 years, belonging to the Universidad Mayor, Temuco. To determine the perception of the sweet taste, an organoleptic test was used that measures the degree of satisfaction with the sweet solution, along with this, weight and height measurements were made to determine the Body Mass Index. Results: Final sample comprised 319 people, of which 30.1% were men and 69.9% women. No significant differences were observed in the preference for solutions with a higher concentration of sucrose according to nutritional status. However, a predictive model developed showed that men prefer the solutions with the highest concentration of sugar regardless of age and nutritional status. Conclusions: It is necessary to develop new studies to clarify whether the preference for sweet taste favors the development of obesity and overweight, or if it is the nutritional composition of processed or ultraprocessed foods, which is having a greater negative impact on the nutritional status of the population.

Introducción: La salud metabólica en universitarios ha cobrado relevancia ante el aumento de factores de riesgo no visibles por métodos tradicionales.. Objetivo: Determinar la influencia de la masa muscular relativa y la grasa visceral sobre el riesgo metabólico en estudiantes universitarios.Metodología: Se realizó un estudio transversal con 325 estudiantes entre 18 y 35 años. Se aplicaron técnicas de bioimpedancia para estimar composición corporal y se utilizó regresión logística binaria ajustada por edad, sexo, porcentaje de grasa corporal y grasa visceral.. Resultados: El 68.31% de los participantes presentó alto riesgo metabólico. El nivel de grasa visceral fue el principal predictor del riesgo (OR = 3.18; p < 0.001). El sexo masculino mostró un efecto protector (OR = 0.25; p = 0.031), mientras que la masa muscular relativa no fue significativa.Discusión: Los hallazgos concuerdan con literatura reciente que posiciona la grasa visceral como marcador metabólico superior al IMC y la grasa subcutánea. La no significancia de la masa muscular podría explicarse por el efecto predominante de la adiposidad visceral.. Conclusiones: La grasa visceral es un factor determinante del riesgo metabólico en jóvenes universitarios. Se recomienda implementar programas de detección temprana y estrategias centradas en la reducción de adiposidad visceral y el fortalecimiento muscular.