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Biocomposite development, as a sustainable alternative to fossil-derived materials with diverse industrial applications, requires expediting the design process and reducing production costs. Simulation methods offer a solution to these challenges. The main aspects to consider in simulating composite materials successfully include accurately representing microstructure geometry, carefully selecting mesh elements, establishing appropriate boundary conditions representing system forces, utilizing an efficient numerical method to accelerate simulations, and incorporating statistical tools like experimental designs and re-regression models. This study proposes a comprehensive methodology encompassing these aspects. We present the simulation using a numerical homogenization technique based on FEM to analyze the mechanical behavior of a composite material of a polyhydroxybutyrate (PHB) biodegradable matrix reinforced with cylindrical inclusions of flax and kenab. Here, the representative volume element (RVE) considered the geometry, and the numerical homogenization method (NHM) calculated the macro-mechanical behavior of composites. The results were validated using the asymptotic homogenization method (AHM) and experimental data, with error estimations of 0.0019% and 7%, respectively. This model is valuable for predicting longitudinal and transverse elastic moduli, shear modulus, and Poisson's coefficient, emphasizing its significance in composite materials research.

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The addition of probiotic bacteria to a meat batter allows the development of functional fermented sausages. The aim of this work was to study the effect of microencapsulated Lactiplantibacillus plantarum BFL (EP) and as free cells (FP) on microbiological, physicochemical, and sensory parameters of fermented sausages during the drying stage and on the product ready for consumption. The microencapsulation of L. plantarum BFL did not improve its viability during the drying stage. In addition, sausages inoculated with L. plantarum BFL (FP and EP) caused lower residual nitrites values, pH values and Escherichia coli counts than the Control (C). However, only the presence of free cells of L. plantarum BFL (FP) caused a decrease in the Enterobacteriaceae and mannitol salt-positive Staphylococcus counts. In the sensory analysis, no significant differences were found in the acceptability of the different sausages. However, the acidity in probiotic sausages (FP and EP) was an attribute that consumers highlighted. The probiotic L. plantarum BFL could adapt and survive at high doses in the matrix of an industrial fermented sausage. Therefore, its use could represent a strategy both for biocontrol of pathogens and for the development of functional meat products.

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Mutations in the transcription factor Phox2b cause congenital central hypoventilation syndrome (CCHS). The syndrome is characterized by hypoventilation and inability to regulate breathing to maintain adequate O2 and CO2 levels. The mechanism by which CCHS impact respiratory control is incompletely understood, and even less is known about the impact of the non-polyalanine repeat expansion mutations (NPARM) form. Our goal was to investigate the extent by which NPARM Phox2b mutation affect (a) respiratory rhythm; (b) ventilatory responses to hypercapnia (HCVR) and hypoxia (HVR); and (c) number of chemosensitive neurons in mice. We used a transgenic mouse line carrying a conditional Phox2bΔ8 mutation (same found in humans with NPARM CCHS). We crossed them with Atoh1cre mice to introduce mutation in regions involved with respiratory function and central chemoreflex control. Ventilation was measured by plethysmograph during neonatal and adult life. In room air, mutation in neonates and adult did not greatly impact basal ventilation. However, Phox2bΔ8, Atoh1cre increased breath irregularity in adults. The HVR and HCVR were impaired in neonates. The HVR, but not HCVR, was still partially compromised in adults. The mutation reduced the number of Phox2b+/TH--expressing neurons as well as the number of fos-activated cells within the ventral parafacial region (also named retrotrapezoid nucleus [RTN] region) induced by hypercapnia. Our data indicates that Phox2bΔ8 mutation in Atoh1-expressing cells impaired RTN neurons, as well as chemoreflex under hypoxia and hypercapnia specially early in life. This study provided new evidence for mechanisms related to NPARM form of CCHS neuropathology.

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Parkinson's disease (PD) patients often experience impairment of autonomic and respiratory functions. These include conditions such as orthostatic hypotension and sleep apnea, which are highly correlated with dysfunctional central chemoreception. Blood flow is a fundamental determinant of tissue CO2/H+, yet the extent to which blood flow regulation within chemoreceptor regions contributes to respiratory behavior during neurological disease remains unknown. Here, we tested the hypothesis that 6-hydroxydopamine injection to inducing a known model of PD results in dysfunctional vascular homeostasis, biochemical dysregulation, and glial morphology of the ventral medullary surface (VMS). We show that hypercapnia (FiCO2 = 10%) induced elevated VMS pial vessel constriction in PD animals through a P2-receptor dependent mechanism. Similarly, we found a greater CO2-induced vascular constriction after ARL67156 (an ectonucleotidase inhibitor) in control and PD-induced animals. In addition, we also report that weighted gene correlational network analysis of the proteomic data showed a protein expression module differentially represented between both groups. This module showed that gene ontology enrichment for components of the ATP machinery were reduced in our PD-model compared to control animals. Altogether, our data indicate that dysfunction in purinergic signaling, potentially through altered ATP bioavailability in the VMS region, may compromise the RTN neuroglial vascular unit in a PD animal model.

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Research on host response to infectious disease often involves pharmacological induction of immunosuppression, frequently through administration of dexamethasone. Reports on the effect of dexamethasone in birds are largely restricted to poultry and pigeons. This study describes changes in white blood cell (WBC) differentials, hemoparasite counts, splenic histology, and splenic CD3 immunoreactivity in House Finches (Haemorhous mexicanus). Experimental group birds (n=9) were treated with a daily intramuscular injection of 25 µg of dexamethasone for 8 d; a control group (n=9) received daily saline solution. Smears were made with blood collected immediately before the first dose (day 0) and on d 4, 8, and 9, and stained with modified Wright. The WBC differential counts were performed by three blinded observers, parasite counts by two blinded observers, and histology by one blinded observer. Dexamethasone-treated birds experienced relative heterophilia and lymphopenia on d 4 (P=0.008); heterophilia was also present at d 8 (P=0.018). Hemosporidian counts were significantly increased in dexamethasone-treated birds on d 4 and 8 (P=0.048 and P=0.031, respectively). In contrast with control birds, all dexamethasone-treated birds lacked histologically apparent splenic lymphoid follicles (P<0.001). No significant difference was observed in splenic CD3 immunoreactivity between groups. Our results indicate that dexamethasone has an effect on the hematologic profile of House Finches and suggest that it may be a useful method to induce immunosuppression in this species.

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The Stefan problem regarding the formation of several liquid-solid interfaces produced by the oscillations of the ambient temperature around the melting point of a phase change material has been addressed by several authors. Numerical and semi-analytical methods have been used to find the thermal response of a phase change material under these type of boundary conditions. However, volume changes produced by the moving fronts and their effects on the thermal performance of phase change materials have not been addressed. In this work, volume changes are incorporated through an additional equation of motion for the thickness of the system. The thickness of the phase change material becomes a dynamic variable of motion by imposing total mass conservation. The modified equation of motion for each interface is obtained by coupling mass conservation with a local energy-mass balance at each front. The dynamics of liquid-solid interface configurations is analyzed in the transient and steady periodic regimes. Finite element and heat balance integral methods are used to verify the consistency of the solutions to the proposed model. The heat balance integral method is modified and adapted to find approximate solutions when two fronts collide, and the temperature profiles are not smooth. Volumetric corrections to the sensible and latent heat released (absorbed) are introduced during front formation, annihilation, and in the presence of two fronts. Finally, the thermal energy released by the interior surface is estimated through the proposed model and compared with the solutions obtained through models proposed by other authors.

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Two mass-accommodation methods are proposed to describe the melting of paraffin wax used as a phase-change material in a centrally heated annular region. The two methods are presented as models where volume changes produced during the phase transition are incorporated through total mass conservation. The mass of the phase-change material is imposed as a constant, which brings an additional equation of motion. Volume changes in a cylindrical unit are pictured in two different ways. On the one hand, volume changes in the radial direction are proposed through an equation of motion where the outer radius of the cylindrical unit is promoted as a dynamical variable of motion. On the other hand, volume changes along the axial symmetry axis of the cylindrical unit are proposed through an equation of motion, where the excess volume of liquid constitutes the dynamical variable. The energy-mass balance at the liquid-solid interface is obtained according to each method of conceiving volume changes. The resulting energy-mass balance at the interface constitutes an equation of motion for the radius of the region delimited by the liquid-solid interface. Subtle differences are found between the equations of motion for the interface. The differences are consistent with mass conservation and local mass balance at the interface. Stationary states for volume changes and the radius of the region delimited by the liquid-solid interface are obtained for each mass-accommodation method. We show that the relationship between these steady states is proportional to the relationship between liquid and solid densities when the system is close to the high melting regime. Experimental tests are performed in a vertical annular region occupied by a paraffin wax. The boundary conditions used in the experimental tests produce a thin liquid layer during a melting process. The experimental results are used to characterize the phase-change material through the proposed models in this work. Finally, the thermodynamic properties of the paraffin wax are estimated by minimizing the quadratic error between the temperature readings within the phase-change material and the temperature field predicted by the proposed model.

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Front tracking and enthalpy methods used to study phase change processes are based on a local thermal energy balance at the liquid-solid interface where mass accommodation methods are also used to account for the density change during the phase transition. Recently, it has been shown that a local thermal balance at the interface does not reproduce the thermodynamic equilibrium in adiabatic systems. Total thermal balance through the entire liquid-solid system can predict the correct thermodynamic equilibrium values of melted (solidified) mass, system size, and interface position. In this work, total thermal balance is applied to systems with isothermal-adiabatic boundary conditions to estimate the sensible and latent heat stored (released) by KNO3 and KNO3/NaNO3 salts which are used as high-temperature phase change materials. Relative percent differences between the solutions obtained with a local thermal balance at the interface and a total thermal balance for the thermal energy absorbed or released by high-temperature phase change materials are obtained. According to the total thermal balance proposed, a correction to the liquid-solid interface dynamics is introduced, which accounts for an extra amount of energy absorbed or released during the phase transition. It is shown that melting or solidification rates are modified by using a total thermal balance through the entire system. Finally, the numerical and semi-analytical methods illustrate that volume changes and the fraction of melted (solidified) solid (liquid) estimated through a local thermal balance at the interface are not invariant in adiabatic systems. The invariance of numerical and semi-analytical solutions in adiabatic systems is significantly improved through the proposed model.

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RESUMEN Introducción: los estilos de vida modernos y la modificación de los hábitos alimentarios han convertido al síndrome metabólico en un problema de salud pública. La incidencia de los trastornos metabólicos en la infancia y la adolescencia han experimentado un importante despunte que amerita mayor estudio y evaluación, y permite establecer estrategias de prevención y pesquisa, para así evitar o limitar el daño en la vida adulta. Objetivo: realizar la caracterización químico sanguíneo del síndrome metabólico en estudiantes del preuniversitario Micaela Riera Oquendo del municipio Manzanillo, provincia Granma en el año 2018. Métodos: se estudiaron 50 estudiantes del preuniversitario Micaela Riera Oquendo del municipio Manzanillo, provincia Granma en el año 2018, a partir de un estudio descriptivo prospectivo en el que evaluaron variables como: edad, sexo, exámenes complementarios, toma de la presión arterial, determinación del índice de masa corporal y los tipos de obesidad. Resultados: la mayor parte de las muestras de sangre tomadas dieron positivas a la hiperglicemia, existió un predominio de estudiantes con sobre peso, prevaleció el tipo de obesidad severa. Existieron 14 estudiantes obesos, 20 con hipertensión arterial y 30 con hiperglicemia, factor determinante del síndrome metabólico. Conclusión: existió un predominio de la hiperglicemia como factor determinante del síndrome metabólico.

ABSTRACT Introduction: the styles of modern life and the modification of the habits food, they have converted the syndrome metabolic in a problem of public health. The incident of the disorders metabolic in the childhood and the adolescence has experienced an important it blunt needing a bigger study and evaluation, allowing to establish strategies of prevention and investigation, for so avoid or limit the damage in the grown life. Objective: to make the characterization sanguine chemical of the syndrome metabolic in students of the Micaela Riera Oquendo preuniversity of the Manzanillo municipality, Granma county in the year 2018. Methods: 50 students were studied in the Micaela Riera Oquendo preuniversity of the Manzanillo municipality, Granma county in the year 2018, starting from a descriptive prospective study in the that they evaluated variables like: age, sex, complementary text, taking of the arterial pressure, determination of the IMC and the types of obesity. Results: most they of the patterns of taken blood gave positive to the hyperglycemia, students' prevalence existed with on peso, prevailed the type of severe obesity. They existed 14 obese students, 20 with HTA and 30 with hyper glycaemia, being this the factor decisive of the SM. Conclusion: a prevalence of the hyper glycaemia, like factor existed decisive of the SM.

RESUMO Introdução: estilos de vida modernos e mudanças nos hábitos alimentares tornaram a síndrome metabólica um problema de saúde pública. A incidência de distúrbios metabólicos na infância e na adolescência tem experimentado um aumento significativo que merece um estudo e avaliação mais aprofundados, e permite estabelecer estratégias de prevenção e pesquisa, a fim de evitar ou limitar os danos na vida adulta. Objetivo: realizar a caracterização química sanguínea da síndrome metabólica em alunos da pré-universidade Micaela Riera Oquendo do município de Manzanillo, província de Granma em 2018. Métodos: 50 alunos da pré-universidade Micaela Riera Oquendo, do município de Manzanillo, província de Granma, em 2018, foram estudados a partir de um estudo descritivo prospectivo no qual avaliaram variáveis como: idade, sexo, exames complementares, ingestão de pressão arterial, determinação do índice de massa corporal e tipos de obesidade. Resultados: a maioria das amostras de sangue colhidas deram positivo para hiperglicemia, houve predominância de estudantes com sobrepeso, prevaleceu o tipo de obesidade grave. Havia 14 estudantes obesos, 20 com pressão alta e 30 com hiperglicemia, determinante da síndrome metabólica. Conclusão: houve predomínio da hiperglicemia como fator determinante na síndrome metabólica.

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RESUMEN Introducción: los grandes asesinos de la historia son las bacterias y los virus, a mediados de diciembre la humanidad comenzó a ser azotada por un nuevo virus SARS-CoV-2, originando una enfermedad llamada COVID 19. Objetivo: evaluar el nivel de conocimientos y el cumplimiento de las medidas preventivas sobre la COVID-19 en los pacientes antes y después de tener la presencia en el área de salud de un caso positivo a la Covid-19. Método: se realizó un estudio descriptivo con fase de intervención a los pacientes de tres Manzanas del consultorio # 12 del policlínico Ángel Ortiz Vázquez del municipio Manzanillo, de la provincia Granma. Resultados: los resultados obtenidos fueron de 583 pacientes un 55,5 por ciento presentan factores de riesgo, antes de la intervención un 34,8% desconocen vías de trasmisión, además un 44.0 % usan el nasobuco de forma inadecuado, lo cual aumento después de la pesquisa fortalecida aumento a un 97.7%, al igual que el nivel de conocimientos que aumento a un 91.0% y satisfacción de la comunidad con las acciones educativas a un 100%. Conclusiones: se observó después de las acciones educativas un aumento en el conocimiento de la enfermedad empoderando a la población de conocimientos y prácticas necesarias, los pacientes cumplieron adecuadamente las medidas preventivas y la satisfacción de la comunidad con el trabajo de los tríos participantes fue favorable.

ABSTRACT Introduction: the greatest killers in history are bacteria and viruses, in mid-December humanity began to be hit by a new SARS-CoV-2 virus, causing a disease called COVID 19. Objective: to assess the level of knowledge and compliance with preventive measures on COVID-19 in patients before and after having the presence in the health area of ​​a positive case for Covid-19. Method: a descriptive study with intervention phase was carried out on the patients of three apples from office # 12 of the Ángel Ortiz Vázquez polyclinic in the Manzanillo municipality, Granma province. Results: the results obtained were from 583 patients, 55.5 percent presented risk factors, before the intervention 34.8% were unaware of transmission routes, and 44.0% used the nasobuco improperly, which increased after the strengthened research increased to 97.7%, as did the level of knowledge that increased to 91.0% and satisfaction of the community with the educational actions to 100%. Conclusions: after the educational actions, an increase in the knowledge of the disease was observed, empowering the population with the necessary knowledge and practices, the patients adequately complied with the preventive measures and the satisfaction of the community with the work of the participating trios was favorable.

RESUMO Introdução: os maiores assassinos da história são bactérias e vírus. Em meados de dezembro, a humanidade começou a ser atingida por um novo vírus SARS-CoV-2, causando uma doença chamada COVID 19. Objetivo: avaliar o nível de conhecimento e a adesão às medidas preventivas do COVID-19 em pacientes antes e depois da presença na área da saúde de um caso positivo para o Covid-19. Método: foi realizado um estudo descritivo com uma fase de intervenção em pacientes de três maçãs do consultório nº 12 da policlínica Ángel Ortiz Vázquez no município de Manzanillo, província de Granma. Resultados: os resultados obtidos foram de 583 pacientes, 55,5 por cento apresentavam fatores de risco, antes da intervenção 34,8% desconheciam as vias de transmissão e 44,0% usavam indevidamente o nasobuco, que aumentava após a pesquisa reforçada aumentou para 97,7%, assim como o nível de conhecimento que aumentou para 91,0% e a satisfação da comunidade com as ações educativas para 100%. Conclusões: após as ações educativas, observou-se um aumento no conhecimento da doença, capacitando a população com os conhecimentos e práticas necessários, os pacientes cumpriram adequadamente as medidas preventivas e a satisfação da comunidade com o trabalho dos trios participantes foi favorável.