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This paper presents the development, characterization, and testing of PP/PE-g-MA composites with 10 and 15 wt% surface-modified aramid fibers, and aluminum-based pigment, as covers for a small drone body for collision protection. The successful fiber surface modification with SiO2 by the sol-gel method using TEOS was confirmed by FTIR, SEM, and EDS analyses. The composites were characterized by FTIR and SEM analyses and surface energy and water contact angle measurements and tested in terms of tensile, flexural, impact, and thermal properties. The materials exhibited hydrophobic character and compact and uniform morphostructures, with increased surface energy with fiber content owed to improved adhesion between modified fibers and the matrix. Compared to the control sample, composites with modified fibers showed an increase by 20% in tensile strength, and 36-52% in the modulus, and an increase by 26-33% in flexural strength and 30-47% in the modulus, with higher values at room temperature. Impact resistance of modified fiber composites showed an increase by 20-40% compared to the control sample, due to improved interaction between SiO2-modified fibers and maleic anhydride, which inhibits crack formation, allowing higher energies' absorption. The composites were vacuum-thermoformed on 3D-printed molds as a two-part cover for the body of a drone, successfully withstanding the flight test.
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(1) Background: There has been a growing interest in understanding the causes of obesity and developing effective prevention strategies. Lifestyle change programs are often considered the gold standard for weight reduction, and they can help individuals with obesity achieve an annual weight loss of around 8-10%. The aim of this review was to evaluate the effect of food during the winter holidays. This knowledge will serve as a valuable foundation for the development of targeted interventions and prevention programs. (2) Methods: We conducted a systematic search of the literature via one database (PubMed). The search was limited to studies published in English in the last 10 years, with adult participants, but without specifying limits regarding the study design. We excluded articles that addressed intermittent fasting diets or weight loss intervention methods during the holidays through various diets. (3) In separate sections, we analyzed the psychological causes of gaining weight during the winter holidays, behavioral patterns, prevention strategies and the nutritional composition of the different types of food served during the festive period. Results: Using the combination of the terms "holiday and obesity", "holiday and weight gain", "festive season and obesity", and "festive season and weight gain" we obtained 216 results involving the addressed topic. Thus, only ten articles remained after screening, with a total of 4627 participants. Most participants experienced weight fluctuations during the study period, particularly during holidays. One concerning observation was that most of the weight gained during these periods was maintained even after the end of the studies, especially in those with obesity. A supervised exercise program and a controlled diet at work over the Christmas period are effective strategies for avoiding weight gain and its deleterious effects in people with metabolic syndrome or weight problems. (4) In addition, attention must be focused on the psycho-social factors during the holidays because for some people it is a stressful period and can cause a much higher caloric consumption. The simplest method to approach during the holidays is to implement small tips and tricks during this period that will prevent individuals from gaining extra pounds. Conclusions: It is essential to acknowledge that obesity is a multifaceted condition that requires a comprehensive and multidisciplinary approach to address its underlying factors and provide ongoing assistance to individuals in their weight-management endeavors. Even the most effective short-term interventions are likely to produce continued positive outcomes with persistent intervention and support.
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Vacaciones y Feriados , Obesidad , Adulto , Humanos , Estaciones del Año , Obesidad/prevención & control , Aumento de Peso , Conducta Alimentaria , Pérdida de PesoRESUMEN
Composite materials are materials with anisotropic properties that are created by combining several different components in a way that allows the best qualities of each component to be used. In this paper, raw materials were used to obtain composite materials of the type TPU/PP/BaTiO3 powder. The thermogravimetric analysis, dynamic differential calorimetry, and scanning electron microscopy were carried out. The preliminary tests for making specific filaments for 3D printing with a diameter of 1.75 mm were carried out on a laboratory extruder. The purpose of the experiment was to develop the optimal extrusion temperatures and the speed of drawing the filament to make filaments with rigorously constant dimensions, and the variation in diameter had a maximum of 10%.
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BACKGROUND: Water scarcity is a worldwide problem that leads to environmental and economic issues. Agriculture is one of the main consumers of water for irrigation and fertilization and almond is the major tree nut crop in the Mediterranean area. Furthermore, there is a continuous growing demand for healthy, vegan and sustainable products. Consequently, the present study aimed to chemically characterize almond milk powder enriched with probiotics manufactured from hydroSOStainable almonds (i.e. generated under water stress conditions). Almond milk powder enriched with probiotic bacteria was produced with almonds grown under optimal irrigation conditions (100% of the crop evapotranspiration) and was chemically compared to the samples made from hydroSOStainable almonds. Antioxidant activity, total phenolic content (TPC), minerals, organic acids and sugars, fatty acids, and descriptive sensory analysis were evaluated. RESULTS: The results showed that almond milk powder produced from hydroSOStainable almonds had a higher content of TPC, polyunsaturated fatty acids (PUFAs), PUFAs/saturated fatty acids (SFAs) ratio and PUFAs/monounsaturated fatty acids ratio, as well as almond and nutty flavors. Moderate and sustained deficit irrigation leads to powders with a higher content of PUFAs and PUFAs/SFAs ratio, which are parameters of utmost importance for health. CONCLUSION: Using these strategies, between 66% and 76% of the irrigation water can be saved, producing hydroSOStainable almond milk powder higher in TPC and PUFAs, as well as positive sensory attributes, compared to that from fully irrigated almonds. These findings may have a positive impact in both agriculture and food industry, allowing water savings and high quality and sustainable food products to be obtained. © 2020 Society of Chemical Industry.
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Nueces/química , Preparaciones de Plantas/química , Preparaciones de Plantas/metabolismo , Prunus dulcis/metabolismo , Deshidratación , Ácidos Grasos/análisis , Ácidos Grasos/metabolismo , Manipulación de Alimentos , Humanos , Nueces/crecimiento & desarrollo , Nueces/metabolismo , Fenoles/análisis , Fenoles/metabolismo , Prunus dulcis/química , Prunus dulcis/crecimiento & desarrollo , Gusto , Agua/metabolismoRESUMEN
Gluten free products available on the market have a low textural quality associated with high crumbly structure, low-flavor, aroma, poor mouthfeel, less appearance, in comparison with the conventional final baked products. The aim of this study was to assess the influence of rice sourdough fermented with Lactobacillus spicheri DSM 15429 strain on textural, volatile profile, and sensorial properties of gluten free muffins in order to obtain baked goods with improved quality characteristics. Lactobacillus spicheri is a novel strain isolated from industrial rice sourdough but unexploited for bakery products manufacturing. The results showed that Lactobacillus spicheri DSM 15429 was able to growth in the rice flour influencing the texture and the volatile profile of gluten free muffins as well as their sensory characteristics. Both, textural parameters and volatiles recorded significant differences comparing to muffins obtained with a spontaneously fermented rice sourdough. Hardness and cohesiveness decreased while springiness and resilience of gluten free muffins improved their values. The volatile profile of gluten free muffins was significantly improved by utilization of the rice sourdough fermented with Lactobacilus spicheri DSM 15429. 3-methylbutanal, 2-methylbutanal, acetophenone and limonene were the main volatile derivatives responsible for aroma and odor scores of sensory analysis.
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BACKGROUND: The combination of the nutritional profile of almond milk with the benefits of probiotic bacteria is an interesting development to meet the demand for sustainable and health-promoting food. Almond milk inoculated with probiotic Lactobacillus plantarum (ATCC8014) was spray dried and the almond, its milk, and powders were characterized physicochemically. Samples were characterized in terms of bacterial survival before and after atomization. Bacterial viability and total fatty acid changes were studied during 8 months' storage at 4 and 22 °C. RESULTS: Results showed adequate physicochemical properties and an optimal bacterial survival rate, maintaining almost the same values before and after the spray-drying operation. A decrease was observed in the cell viability for samples stored at 4 °C. However, the cell count was maintained above the minimum level suggested (107 living cells) to allow potential probiotic functionality for 8 months. On the other hand, the count cell of powders stored at 22 °C was below the minimum level required after 6 months. The fatty acids profile was not significantly (P > 0.05) affected by storage time and temperature. CONCLUSION: A new almond-based-product with probiotics was developed to meet consumer demands. Almond nutrients were recovered from almond milk powder and were found to be a good source of K and high in Mg and in monounsaturated fat. The viability of bacteria was assured during 8 months of storage at 4 °C and up to 6 months for samples stored at 22 °C. © 2020 Society of Chemical Industry.
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Microbiología de Alimentos/métodos , Lactobacillus plantarum/crecimiento & desarrollo , Preparaciones de Plantas/química , Probióticos/química , Prunus dulcis/química , Recuento de Colonia Microbiana , Manipulación de Alimentos , Almacenamiento de Alimentos , Viabilidad Microbiana , Valor Nutritivo , Polvos/química , Prunus dulcis/microbiología , Semillas/química , Semillas/microbiología , Secado por PulverizaciónRESUMEN
The goal of this research is the investigation of a way to maximize the production of docosahexaenoic acid (DHA) and ß-carotene by optimizing the culture conditions of their sources, microalgae Schizochytrium limacinum and fungus Blakeslea trispora respectively, in a fermentation medium. The influencing factors in the fermentation process for producing DHA and ß-carotene have proven to be: the concentration of carbon source (different glycerol crude and pure concentrations) for both of them, and in particular temperature for DHA and pH for ß-carotene. Testing the effect of these parameters was determined: biomass, DHA and ß-carotene concentration. The highest production by S. limacinum was obtained at 25 °C, while using a quantity of 90 g/L of glycerol (crude or pure) as a carbon source. Temperature was the main factor that influenced the biosynthesis of DHA. The quantification of DHA was made by GC-MS chromatography, followed by a purification process, with the end result of DHA in pure phase. The maximum quantities for ß-carotene production were obtained with pH 7 and 60 g/L of crude glycerol. The results highlight the possibility of using crude glycerol as a low-cost substrates for growth of microalgae S. limacinum and of fungus B. trispora in order to obtain the crucial molecules: docosahexaenoic acid and ß-carotene.
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Ácidos Docosahexaenoicos/metabolismo , Glicerol/química , Microalgas/crecimiento & desarrollo , Fermentación , Microalgas/metabolismo , beta CarotenoRESUMEN
The adsorption potential of alkaline treated straw (wheat and corn) in mixture with soil, has been investigated for the removal of sulfonylurea molecules from an aqueous solutions. The surface characteristics were investigated by scanning electron microscopy and Fourier Transform Infrared - FTIR, while the adsorbent capacity was evaluated using batch sorption tests and liquid chromatography coupled with mass spectrometry. Surface analysis of alkaline treated straw samples by scanning electron microscopy - SEM showed the increasing of the surface roughness improving their functional surface activity. An increase (337.22 mg g-1) of adsorption capacity of sulfonylurea molecules was obtained for all studied straw. The Langmuir isotherm model was the best model for the mathematical description of the adsorption process indicating the forming of a surface sorption monolayer with a finite number of identical sites. The kinetics of sulfonylurea herbicide followed the pseudo-second order mechanism corresponding to strong chemical interactions. The results sustained that the alkaline treated straw have biosorption characteristics, being suitable adsorbent materials.