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The environmental and economic impact of an oil spill can be significant. Biotechnologies applied during a marine oil spill involve bioaugmentation with immobilised or encapsulated indigenous hydrocarbonoclastic species selected under laboratory conditions to improve degradation rates. The environmental factors that act as stressors and impact the effectiveness of hydrocarbon removal are one of the challenges associated with these applications. Understanding how native microbes react to environmental stresses is necessary for effective bioaugmentation. Herein, Micrococcus luteus and M. yunnanensis isolated from a marine oil spill mooring system showed hydrocarbonoclastic activity on Maya crude oil in a short time by means of total petroleum hydrocarbons (TPH) at 144 h: M. luteus up to 98.79 % and M. yunnanensis 97.77 % removal. The assessment of Micrococcus biofilms at different temperature (30 °C and 50 °C), pH (5, 6, 7, 8, 9), salinity (30, 50, 60, 70, 80 g/L), and crude oil concentration (1, 5, 15, 25, 35 %) showed different response to the stressors depending on the strain. According to response surface analysis, the main effect was temperature > salinity > hydrocarbon concentration. The hydrocarbonoclastic biofilm architecture was characterised using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Subtle but significant differences were observed: pili in M. luteus by SEM and the topographical differences measured by AFM Power Spectral Density (PSD) analysis, roughness was higher in M. luteus than in M. yunnanensis. In all three domains of life, the Universal Stress Protein (Usp) is crucial for stress adaptation. Herein, the uspA gene expression was analysed in Micrococcus biofilm under environmental stressors. The uspA expression increased up to 2.5-fold in M. luteus biofilms at 30 °C, and 1.3-fold at 50 °C. The highest uspA expression was recorded in M. yunnanensis biofilms at 50 °C with 2.5 and 3-fold with salinities of 50, 60, and 80 g/L at hydrocarbon concentrations of 15, 25, and 35 %. M. yunnanensis biofilms showed greater resilience than M. luteus biofilms when exposed to harsh environmental stressors. M. yunnanensis biofilms were thicker than M. luteus biofilms. Both biofilm responses to environmental stressors through uspA gene expression were consistent with the behaviours observed in the response surface analyses. The uspA gene is a suitable biomarker for assessing environmental stressors of potential microorganisms for bioremediation of marine oil spills and for biosensing the ecophysiological status of native microbiota in a marine petroleum environment.

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Breastfeeding is recognized worldwide as the best option for infant feeding. Expressing breast milk is an alternative for mothers to provide their infants all the benefits of maternal milk. During breast milk expression, mothers receive a distinct kind of sensory stimulation, because there is no direct bodily or affective interaction with their infants, many women report feeling isolated, generating a love-hate relation with pumping, and even low levels of satisfaction while expressing breast milk. While it is well known that the prefrontal, parietal, and temporal cortices play important roles in the emotional and cognitive processing of maternal stimuli, knowledge about how these cortical areas function during breastfeeding is lacking. This study was designed to characterize EEG activity in the prefrontal and parietal cortices and the affective scores of primiparous breastfeeding mothers during two conditions of milk expression: breast milk expression and direct breastfeeding. Participants reported higher valence and arousal and a pleasant state during direct breastfeeding. In the direct breastfeeding condition, both prefrontal areas showed a higher absolute power (AP) of the slow bands, with a lower AP of the alpha band in the parietal cortex. A lower correlation between frontopolar and dorsolateral areas with a higher correlation between prefrontal and parietal cortices was obtained mainly in the right hemisphere. This EEG activity could be linked to an internal state of focused attention and, simultaneously, open monitoring of the environment that suggests an integration of the motive-emotional and cognitive processes necessary for adequate mother-baby interaction during direct breastfeeding.

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Strawberries are highly consumed around the world; however, the post-harvest shelf life is a market challenge to mitigate. It is necessary to guarantee the taste, color, and nutritional value of the fruit for a prolonged period of time. In this work, a nanocoating based on chitosan and ZnO nanoparticles for the preservation of strawberries was developed and examined. The chitosan was obtained from residual shrimp skeletons using the chemical method, and the ZnO nanoparticles were synthesized by the close-spaced sublimation method. X-ray diffraction, scanning electron microscopy, electron dispersion analysis, transmission electron microscopy, and infrared spectroscopy were used to characterize the hybrid coating. The spaghetti-like ZnO nanoparticles presented the typical wurtzite structure, which was uniformly distributed into the chitosan matrix, as observed by the elemental mapping. Measurements of color, texture, pH, titratable acidity, humidity content, and microbiological tests were performed for the strawberries coated with the Chitosan/ZnO hybrid coating, which was uniformly impregnated on the strawberries' surface. After eight days of storage, the fruit maintained a fresh appearance. The microbial load was reduced because of the synergistic effect between chitosan and ZnO nanoparticles. Global results confirm that coated strawberries are suitable for human consumption.

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INTRODUCTION: Drug-resistant epilepsy presents high worldwide prevalence and is difficult to control despite the wide variety of available antiepileptic drugs (AED). The modified Atkins diet (MAD) is an additional treatment alternative. Several studies have addressed the use of the ketogenic diet and MAD in children with drug-resistant epilepsy, but insufficient research has been conducted into adults with the same condition. OBJECTIVE: To evaluate the effectiveness and tolerability of, and adherence to, the MAD in adults with drug-resistant epilepsy. MATERIAL AND METHODS: We conducted a 6-month pre-post prospective study at a reference hospital. Patients were prescribed the MAD with limited carbohydrate intake and unlimited fat intake. We conducted clinical and electroencephalographic follow-up according to the relevant guidelines, and assessed adverse effects changes in laboratory findings, and adherence. RESULTS: Thirty-two patients with drug-resistant epilepsy were included in the study. Patients' mean age was 30 years, mean disease progression time was 22 years, and all patients had focal or multifocal epilepsy. Thirty-four percent of patients presented > 50% decreases in overall seizure frequency (P =  .001); seizure control was greater in the first month and subsequently declined. These patients presented weight loss (RR: 7.2; 95% CI, 1.3-39.5; P = .02), good to fair adherence only in the first and third months (RR: 9.4; 95% CI, 0.9-93.6; P = .04 and RR: 0.4; 95% CI, 0.30-0.69; P = .02, respectively). Tolerability data showed that the MAD is safe: adverse effects were minor and short-lived in most cases, with the exception of mild to moderate hyperlipidaemia in one-third of patients. The adherence rate was 50% at the end of the study. CONCLUSIONS: In adults with drug-resistant focal epilepsy, the MAD showed adequate tolerability and moderate but decreasing effectiveness and adherence, probably due to a preference for a carbohydrate-based diet.

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Quorum sensing (QS) is a process of cell-cell communication for bacteria such as E. coli and Salmonella that cause foodborne diseases, with the production, release, and detection of autoinducer (AI) molecules that participate in the regulation of virulence genes. All of these proteins are useful in coordinating collective behavior, the expression of virulence factors, and the pathogenicity of Gram-negative bacteria. In this work, we review the natural or synthetic inhibitor molecules of QS that inactivate the autoinducer and block QS regulatory proteins in E. coli and Salmonella. Furthermore, we describe mechanisms of QS inhibitors (QSIs) that act as competitive inhibitors, being a useful tool for preventing virulence gene expression through the downregulation of AI-2 production pathways and the disruption of signal uptake. In addition, we showed that QSIs have negative regulatory activity of genes related to bacterial biofilm formation on clinical artifacts, which confirms the therapeutic potential of QSIs in the control of infectious pathogens. Finally, we discuss resistance to QSIs, the design of next-generation QSIs, and how these molecules can be leveraged to provide a new antivirulence therapy to combat diseases caused by E. coli or Salmonella.

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Renealmia alpinia (Rottb.) Maas pulp was processed by spray drying using Maltodextrin (MDX), and Gum Arabic (GA), and the mixture of both encapsulating agents (MDX-GA). Yield, moisture, water activity (a w ), apparent and bulk densities, size and morphology of capsules, color, and antioxidant potential (antioxidant activity, total carotenoids, and phenolic compounds) were analyzed. The encapsulates were incorporated as pigments in yogurt and the stability of antioxidant compounds (1, 7, 14, 21, and 28 days of storage) and the sensory properties were evaluated. The yields of all formulations (MDX, GA, MDX-GA) were around 17.86% with low moisture and a w range values (2.62-3.29% and 0.276-0.309, respectively). The microcapsules presented multiples particle sizes (0.67-27.13 µm) with irregular and smooth surfaces. Furthermore, these capsulates preserved yellow color and the retention of carotenoids was significantly higher with MDX (34.12 mg/100 g of powder), while the phenolic compounds and antioxidant activity increased with GA (474.17 mg GAE/100 g and 552.63 mg TE/100 g of powder, respectively). The main compounds ß-carotene and gallic acid were identified and quantified in positive and negative mode respectively using LC-MS/MS. Finally, the addition of the encapsulated pigments to yogurt allowed to obtain a yellow coloration and the yogurt added with MDX-GA presented the best formulation with not significant changes in antioxidant activity and acceptable sensory attributes up 28 days of storage.

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La investigación constituye una aproximación cualitativa al fenómeno de la sexualidad adolescente, centrada en describir la mentalidad de los jóvenes respecto a su propia sexualidad. Es decir; los conocimientos relacionados a las prácticas sexuales y la salud reproductiva asociada a dichos conocimientos, manifestados por los estudiantes participantes en el estudio. La finalidad fue descubrir la calidad y procedencia del tipo de conocimiento que poseen los jóvenes y su coherencia con las ideas sobre las prácticas sexuales y la salud reproductiva, a fin de identificar qué porcentaje de la población posee un conocimiento confiable, atendiendo a la calidad. Condición que los exponen a adquirir infecciones de transmisión sexual que pueden poner en riesgo su salud reproductiva. El objetivo perseguido fue: describir el tipo de conocimiento y las prácticas sobre salud sexual y reproductiva en los 306 estudiantes del primer año de la Universidad Salvadoreña Alberto Masferrer que participaron en el estudio. Los resultados señalan que un 30 % de la población estudiada, no poseen un conocimiento confiable, sino basado en creencias y mitos, que no existe una fuente científica confiable que les permita desarrollarse plenamente en esta área fundamental en sus vidas. El otro descubrimiento fue la presencia de un carácter constante es sus conocimientos: y que los conocimientos que poseen no son coherentes entre sí. Por lo que carecen consistencia y revelan la falta de correspondencia a un sistema teórico confiable para orientar correctamente su sexualidad y su salud sexual y reproductiva.

This research constitutes a qualitative approximation to the phenomenon of adolescent sexuality focused on describing the mentality of young people regarding their own sexuality. That is, the knowledge as it relates to the sexual practices and reproductive health associated with said knowledge, manifested (expressed) by the students participating in the study. The purpose was to describe the quality and provenance of the type of knowledge that young people possess; its coherence with ideas about sexual practices and reproductive health, lastly to identify the type of knowledge the population have and how reliable is such knowledge. Conditions that exposes them to acquire sexually transmitted diseases potentially putting their reproductive health at risk. The objective was to describe the type of knowledge and practices on sexual and reproductive health in 306 first year Salvadorian University Alberto Masferrer students, who participated in the study. The results indicates that 30% of the studied population do not possess reliable knowledge, but based on beliefs, and myths, there is no reliable scientific source that allows them to fully develop in this fundamental area in their life. The other discovery was the presence of constant character in their knowledge: and that the knowledge possessed is not coherent within each other. They lack consistency and reveal a lack of correspondence and reliable theoretical system to correctly guide their sexuality and sexual and reproductive health.

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Recently, chitin and chitosan are widely investigated for food preservation and active packaging applications. Chemical, as well as biological methods, are usually adopted for the production of these biopolymers. In this study, modification to a chemical method of chitin synthesis from shrimp shells has been proposed through the application of high-frequency ultrasound. The impact of sonication time on the deproteinization step of chitin and chitosan preparation was examined. The chemical identities of chitin and chitosan were verified using infrared spectroscopy. The influence of ultrasound on the deacetylation degree, molecular weight and particle size of the biopolymer products was analysed. The microscopic characteristics, crystallinity and the colour characteristics of the as-obtained biopolymers were investigated. Application of ultrasound for the production of biopolymers reduced the protein content as well as the particle size of chitin. Chitosan of high deacetylation degree and medium molecular weight was produced through ultrasound assistance. Finally, the as-derived chitosan was applied for beef preservation. High values of luminosity, chromatid and chrome were noted for the beef samples preserved using chitosan films, which were obtained by employing biopolymer subjected to sonication for 15, 25 and 40 min. Notably; these characteristics were maintained even after ten days of packaging. The molecular weight of these samples are 73.61 KDa, 86.82 KDa and 55.66 KDa, while the deacetylation degree are 80.60%, 92.86% and 94.03%, respectively; in the same order, the particle size of chitosan are 35.70 µm, 25.51 µm and 20.10 µm.

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Aging can be associated with decreasing muscle strength, and related factors are comorbidities, sex, physical activity, and possibly genetic factors. Among genetic factors the renin-angiotensin system is of interest, but data on the Peruvian population is lacking. The objective of our study was to evaluate the association of grip strength and angiotensin convertase enzyme (ACE) polymorphism in Peruvian older people. A cross-sectional study in a convenience sample of 104 participants over 60 years in Lima, Perú, with analysis of the ACE polymorphism, was performed. We studied 104 participants, 46 men (44,2%) and 58 women (55,8%), with a mean age and standard deviation (SD) of 73,7 (7,4) years, range between 60-90 years. The frequency of D/D, I/D and I/I genotypes was 12,7; 43,7 and 43,7% respectively. The genotype distribution of ACE polymorphism agreed with the Hardy-Weinberg equilibrium (p=0,746). The mean (SD) of grip strength in the D/D, I/D and I/I polymorphisms were 24,8 (7,2); 22,8 (7,2) and 23,4 (7,6) kg respectively; no significant difference was observed (p=0,41) between genetic groups. In this small convenience sample of older Peruvians, no association was found between grip strength and ACE genotype.

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Many raw vegetables, such as tomato, chili, onion, lettuce, arugula, spinach, and cilantro, are incorporated into fresh dishes including ready-to-eat salads and sauces. The consumption of these foods confers a high nutritional value to the human diet. However, the number of foodborne outbreaks associated with fresh produce has been increasing, with Escherichia coli being the most common pathogen associated with them. In humans, pathogenic E. coli strains cause diarrhea, hemorrhagic colitis, hemolytic uremic syndrome, and other indications. Vegetables can be contaminated with E. coli at any point from pre- to postharvest. This bacterium is able to survive in many environmental conditions due to a variety of mechanisms, such as adhesion to surfaces and internalization in fresh products, thereby limiting the usefulness of conventional processing and chemical sanitizing methods used by the food industry. The aim of this review is to provide a general description of the behavior and importance of pathogenic E. coli in ready-to-eat vegetable dishes. This information can contribute to the development of effective control measures for enhancing food safety.