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Copyright of Archivos Latinoamericanos de Nutrición is the property of Sociedad Latinoamericana de Nutricion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

La tecnología de mezcla asfáltica tibia (WMA) ha sido un incentivo en la industria asfáltica ya que contribuye a minimizar las emisiones de gases de efecto invernadero al medio ambiente, ayudando a reducir el calentamiento global y la huella de carbono. En esta investigación se evaluó experimentalmente el impacto de dos aditivos WMA sobre las características del ligante asfáltico y la mezcla asfáltica. Entre los resultados, se destacó el impacto de los aditivos en la propiedad de viscosidad del ligante asfáltico. Ambos aditivos redujeron la viscosidad a medida que aumentaba la temperatura en la mezcla. Con respecto a las mezclas asfálticas, la adición de aditivos wma tendió a aumentar la densidad aparente, los vacíos llenos de asfalto, la estabilidad Marshall y a reducir el contenido de vacíos de aire. La incorporación de estos aditivos puede reducir entre un 0.2 y un 0.4% el contenido óptimo de betún.

Copyright of Revista ION is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciencia e Ingenieria Neogranadina is the property of Ciencia e Ingenieria Neogranadina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the most important minimally invasive treatments today in temporomandibular joint osteoarthritis (TMJOA) is the intra-articular exogenous hyaluronic acid (HA) injection, which has yielded good results in pain relief and improves mandibular function with few side effects. However, the effectiveness of HA continues to be controversial, partly due to the heterogeneity in the injection protocols in their molecular weight, viscosity and frequency of infiltration, among other properties. The aim of this review is to identify the differences in the histological and clinical effects of the different types of HA and the frequency of infiltration on TMJ-OA treatment. Materials and methods: A bibliographic search was performed in the PubMed, Web of Science and Scopus databases. The search was limited up to September 2022. Search terms included "osteoarthritis", "hyaluronic acid, "molecular weight", "concentration", "viscosity", "dose" and "temporomandibular", using AND/OR as Boolean terms. Results: Exogenous HA in its different molecular weights offers an improvement in histological and clinical characteristics. Apparently, low and medium molecular weight HA presents better results. No clinical studies related to the degree of HA viscosity were found. Respect to the frequency of infiltration, single injection, weekly injections for 3 weeks, weekly injections for 5 weeks and other protocols are used. However, their comparison is complex. There seems to be differences in the effects of the different HA preparations for the treatment of TMJ-OA, mainly in their molecular weight. However, the evidence remains scant. [ABSTRACT FROM AUTHOR]

La sangre es una mezcla de componentes que tiene su propia identidad. Una de las propiedades físicas que adquiere es su viscosidad, la cual es la resistencia que ofrece para desplazarse. A diferencia de sus componentes (como glucosa, hemoglobina, colesterol, etc.), la sangre no posee un nivel único de viscosidad, sino que esta es variable debido a diversos factores. Exponemos algunos principios físicos que nos permitirán entender mejor esta dinámica de la viscosidad sanguínea, y su posible aplicación en algunos fenómenos hemodinámicos, así como la complejidad de su medición en la práctica clínica habitual.

The purpose of this study was to investigate whether antioxidant-enriched microcrystalline cellulose from almond residue (AE-MCC-AS) affects the physicochemical and textural characteristics of mayonnaise during 56 days of storage at 25 °C. The L* value of the mayonnaise decreased by increasing the AE-MCC-AS ratio; whereas the redness and yellowness values increased. The emulsion stability and viscosity increased by increasing the AE-MCC-AS ratio from 0.2% to 0.4%; however, they decreased with an increase in the AE-MCC-AS ratio from 0.4% to 0.6%. The largest oil droplets were observed in the micrographs of the control, 0.2% AE-MCC-AS-M and 0.6% AE-MCC-AS-M; while the smallest ones were observed in the micrographs of a-tocopherol-M, BHT-M and 0.4% AE-MCCAS-M. During the storage period, the total MUFA and PUFA showed a declining trend in all treatments with a higher decrease in the control; while total SFA showed an upward trend with a higher increase in the control. In terms of textural characteristics, a significant declining trend (P < 0.01) was observed in firmness and consistency; whereas an upward trend was observed in cohesiveness during the storage in all treatments. [ABSTRACT FROM AUTHOR]

Copyright of Acta Médica Peruana is the property of Colegio Medico del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Técnica Industrial: Revista Cuatrimestral de Ingeniería, Industria e Innovación is the property of Fundacion Tecnica Industrial and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Annatto seed oil (ASO) and cupuassu seed fat (CSF) were combined at the ratios: 30:70, 50:50, and 70:30 (% w/w). Their fatty acid profile, nutritional quality, FTIR (Fourier Transform Infrared) spectra, and rheological behavior were evaluated. ASO increased the content of polyunsaturated fatty acids in the blends; whereas CSF conferred higher contents of monounsaturated fatty acids. The blends exhibited low atherogenicity and thrombogenicity indices, suggesting nutritional advantages. The Newtonian fluid behavior and FTIR results suggested that mixing ASO and CSF at different proportions did not affect the functional groups. ASO showed an activation energy value which indicated that this fat viscosity was more sensitive to temperature changes. The Newtonian model proved to be suitable to describe the behavior of samples, according to statistical fit parameters R², χ², and RSS. The resulting blends presented improved physicochemical properties and nutritional attributes, indicating their feasibility for the development of new products. [ABSTRACT FROM AUTHOR]

Copyright of Agronomía Colombiana is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El objetivo de esta investigación fue la caracterización reológica y química del hidrocoloide Senna birostris del distrito de Acobamba, Huancavelica. El hidrocoloide se extrajo por el método de tostado (90 °C y 15 min) y molienda. La composición química proximal exhibió un contenido de 10,37 g de humedad, 1,96 g de ceniza, 6,61 g de grasa, 9,31 g de proteína, 2,15 g de fibra, 69,60 g de carbohidratos y 357,75 kcal, por 100 g de hidrocoloide. La caracterización reológica del hidrocoloide se realizó con tres concentraciones (1, 2 y 3%). Se utilizó un reómetro Haake modelo Viscotester iQ, Thermo Scientific, con geometría Mooney – Ewart. Se estableció un tipo de flujo de dilatación (n > 1) y un coeficiente de consistencia (KOW) de 2,9778 x 10-4 y 1,4491 x 10-3 Pa.sn, para 2% y 3%, respectivamente, a 25 °C. El modelo de Arrhenius se ajustó a los datos experimentales de 25 a 65 °C, con un esfuerzo cortante constante de 70 s-1. La energía de activación fue 42353,92, 2429,74 y 4372,66 J.mol-1, para 1%, 2% y 3%, respectivamente. Estos resultados son prometedores para la aplicación de este hidrocoloide en la industria farmacéutica y la agroindustria.

The alcoholic beverage industry has grown exponentially in terms of the production of alcohol-containing products in an artisanal manner. Thus, it is proposed to implement an agroindustrial production alternative by making fruit wine from curuba (Passiflora mollissima) using a Saccharomyces Cerevisiae (Var. Bayanus) yeast strain. Three phases were developed; the first consisted of obtaining and fermenting the curuba pulp; the second phase included physicochemical and microbiological characterization, evaluating parameters such as pH, acid-base titration, soluble solids, color, viscosity, yeast count by deep seeding on YGC agar and LAB count on MRS agar to verify malolactic fermentation; finally, sensory analysis was performed through a quantitative descriptive analysis (QDA) in solitary and paired. The result obtained was a beverage with a pH of 3,14±0,02, a viscosity of 2,31±0,02 cP, soluble solids content of 7,65±0,07 °Brix and an alcohol content of 12,91±0,19 v/v. Thus, the study demonstrates that curuba has a high biotechnological potential in the elaboration of fermented beverages, offering an additional alterna- tive for the elaboration and commercialization of new products in the department of Huila (Colombia). [ABSTRACT FROM AUTHOR]

Copyright of Revista Fuentes, El Reventón Energético is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of @limentech: Ciencia y Tecnología Alimentaria is the property of Journal @limentech, University of Pamplona and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, the dynamic viscosity of Newtonian fluids is modeled using Eyring's theory and the residual Helmholtz free energy. In order to estimate this energy, a modified Peng-Robinson cubic equation of state is applied. The pseudo-experimental data have been obtained from two databases (DIPPR and NIST databses) most commonly used in the development of thermodynamic models, where DIPPR data are used to obtain the parameters and generalization of the model and the NIST data are used to evaluate the predictive capabilities of the generalization procedure. The adjustable parameters of the model have been determined from data in the liquid and vapor coexistence for n-alkanes and n-alcohols. Later these parameters have been generalized using simple mathematical expressions that depend on the molecular weight of each substance. The predictive capabilities of the model are evaluated in the liquid and vapor single-phases. The absolute deviations during the correlation process are below 3.27%, while in the prediction process they are below 5.60%. The generalized model is extended to binary mixtures using a simple mixture rule with one interaction parameter. The experimental data of the mixtures are obtained from different literature works and the absolute deviations are around 8.19% (without binary interaction coefficients) and 3.45% (with binary interaction coefficients). Finally, the model is compared with others in the literature using an analysis of variance in order to establish if there is a statistically significant difference between the deviations of the models used in the comparison. The statistical results show that the model developed in this work provides acceptable results. [ABSTRACT FROM AUTHOR]

Introducción: En la simulación del proceso de pasteurización de la cerveza envasada, se requiere del uso de los balances de continuidad, energía y cantidad de movimiento, y estos modelos matemáticos en estado no estacionario, necesitan los valores de la densidad, la viscosidad, la capacidad calorífica y la conductividad térmica. Se ha encontrado que algunos investigadores utilizan modelos de las propiedades termofísicas del agua, para estimar las de la cerveza, sin realizar ningún análisis que demuestre que esto sea confiable. Objetivo: Validar el uso de modelos matemáticos para la estimación de las propiedades termofísicas del agua, aplicando técnicas estadísticas, que permitan compararlos con modelos, datos y valores reportados por diferentes autores, para emplearlos posteriormente en la simulación del proceso de pasteurización de la cerveza embotellada. Materiales y Métodos: Para la validación de los modelos de las propiedades del agua se emplearon el análisis de regresión y las pruebas de hipótesis, a partir de las que se realizaron comparaciones entre los modelos y valores reportados. Resultados y Discusión: Al comparar las medias entre las propiedades obtenidas por los modelos para el agua con las obtenidas por otros autores, se obtienen valores de la probabilidad mayores que 0,05, por lo que no se rechaza la hipótesis nula, Ho. Mostrándose que no existen diferencias estadísticamente significativas entre los valores analizados. Conclusiones: Se propone utilizar los modelos correspondientes al agua en la estimación de las propiedades termofísicas de la cerveza, en el rango de temperatura del proceso de pasteurización, en estudios futuros de simulación.

Copyright of Fides et Ratio is the property of Universidad La Salle de Bolivia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The vegetable mucilages traditionally used to clarify sugarcane juices come from balsa wood, guácimo and cadillo, although cocoa shells can also be used. The objective was to establish the state of maturity, chopping condition and time of immersion in water of the national cocoa shell to obtain a natural flocculant. The procedure was established by the heuristic method, prior to establishing the experimental design with 3 factors a*b*c of a complete 2n design, being a factor shell of national cocoa (pintón and mature), b factor condition of cutting (thick pieces from 3.5 to 4.5 cm, and fine pieces from 0.3 to 0.6 cm) and, c factor immersion time in water (60 and 80 minutes), and, from the combination of factors, eight treatments with three repetitions were established, giving 24 experimental units. Ethyl alcohol of 60 °GL in 1.4% was used to accelerate the mucilage extraction process, and 100 ppm of sodium metabisulfite as an antioxidant combined with a thermal shock. The dependent variable was viscosity with a threshold of 30 centipoise. The a1b1c1 treatment (mature national cocoa shell, fine pieces of 0.3 to 0.6 cm, 80 minutes of immersion in water) reached the threshold viscosity established as a goal. It's concluded that the extraction of mucilage from national cocoa shells is feasible for use as an aid in the clarification of sugarcane juices. [ABSTRACT FROM AUTHOR]

Aim: To represent mathematically the reported physico-chemical properties (PCPs) of binary mixtures of 3-bromoanisol + methanol at various temperatures by using a single model with seven curve-fit parameters. Results: Besides the correlation models, the applicability of training the proposed model using a minimum number of experimental data and prediction of the rest of data points with acceptable prediction error is also shown. [ABSTRACT FROM AUTHOR]

Oils are commonly used in cooking as a frying medium which has been constantly subjected to different levels of heating. In this work, we have considered the most commonly used oils namely peanut oil and corn oil. Quality analyses of corn and peanut oils were made by relating macroscopic properties (ultrasonic velocity, viscosity, and density) to microscopic parameters (intermolecular free length, adiabatic compressibility etc.,) by subjecting them to six cycles of heating (190 ËšC). Variation in the mentioned property indexes, the degree of degradation and reusability for the next heating cycle that could be used in the food industry and processing were monitored. Using Newton-Laplace and Wood's equation, the adiabatic compressibility, acoustic impedance, and intermolecular free length of the oil were estimated from the experimental data. Ultrasonic velocity was observed linearly as related to viscosity with the dependency factor (R² = 0.932). With the aid of experiential data, the physical thermodynamic parameters, particularly particle size, packing factor, chemical potential, and L-J potential were computed. A high correlation factor was observed by fitting ultrasonic velocity, viscosity, and density to Parthasarathy and Bakshi, and Rodenbush equations. In the study, ultrasonic velocity, a macroscopic parameter, could be decoded to determine the microscopic variations in oil subjected to different temperatures in an industrial application. [ABSTRACT FROM AUTHOR]

The present study aims to develop a model for dynamic viscosity estimation applied to Newtonian fluids in the liquid and vapor coexistence curve of non-polar and polar substances by applying residual entropy theory. A modified Peng-Robinson equation of state is used to calculate residual entropy. One-hundred and sixteen pure substances and water (67 substances for correlation and 49 substances for prediction) are studied. The model is generalized in terms of normal boiling temperature for 12 organic families using a linear function. The temperature range varies between 104.81 K and 565.48 K and the pressure ranges between 0.01 kPa and 3618.69 kPa. The average absolute deviations for correlation and prediction are below 6.38% and 11.36%, respectively. The generalized model is validated against others developed in the literature. Based on the results obtained, it is concluded that the proposed model is simple and provides acceptable results. [ABSTRACT FROM AUTHOR]

Las reservas de crudo liviano son cada vez más escasas, a diferencia de los descubrimientos de crudo pesado, razón por lo cual se ha enfocado la atención en este tipo de hidrocarburos. Colombia tiene un gran potencial de crudo pesado, sobre todo en las zonas de la Cuenca de los Llanos Orientales (Campos: Rubiales, Castilla, Chichimene, Apiay, Suria), cuyo desarrollo en los últimos años, ha logrado que el 60% de la producción nacional este asociada a este tipo de recurso. La producción de crudo pesado no es fácil, una de las principales dificultades es la alta viscosidad del hidrocarburo, lo cual origina una baja movilidad del mismo y una temprana producción de agua en yacimientos con acuíferos activos. Una de las técnicas más utilizadas para incrementar la productividad en los yacimientos de crudos pesados es la estimulación matricial de pozos, a partir de la cual se pueden modificar las curvas de permeabilidad relativa (alteración de la humectabilidad) y así mejorar la movilidad de estos crudos. Sin embargo es crucial la comprensión de la mojabilidad de la formación para optimizar la recuperación de petróleo. Suponer que una formación es mojable por agua, cuando en realidad no lo es, puede ocasionar daños irreversibles en el yacimiento. Por lo anterior, el presente estudio se centró en desarrollar e implementar un protocolo a nivel de laboratorio, para evaluar tratamientos de estimulación matricial base agua, que tuvieran la capacidad de invertir la mojabilidad natural (generalmente al crudo, debido a la alta afinidad entre el crudo y minerales de roca del yacimiento), hacia una mojabilidad al agua, que conduce a un mejoramiento de la permeabilidad relativa al crudo. El protocolo experimental fue implementado a nivel de laboratorio en el campo Castilla (cuenca de los llanos orientales en Colombia) y se enfocó en tres grandes etapas. 1. Etapa 1: Caracterización básica de fluidos de formación 2. Etapa 2: Evaluación fluido-fluido y comportamiento reológico de fluidos de formación Vs Tratamientos químicos. 3. Etapa 3: Evaluación del efecto sobre la humectabilidad (modificación de ángulos de contacto y permeabilidad relativa). Las principales conclusiones y recomendaciones obtenidas en este estudio son las siguientes: 1. Se desarrolló un protocolo experimental adecuado para la evaluación de microemulsiones y/o aditivos mejoradores de movilidad. 2. La implementación del protocolo permitió seleccionar el mejor tratamiento de alteración de la humectabilidad para el campo Castilla. 3. En la preferencia de la mojabilidad del yacimiento, tienen incidencia: los componentes del petróleo, la química de la salmuera, la superficie mineral, la temperatura, la presión, la tensión interfacial de los fluidos, la presión capilar y la historia de saturación del yacimiento.

The coffee mucilage elimination requires the pectin degradation, often performed by natural fermentation, which is indeed an important stage to obtain washed coffees. Fermentation represents a large part of the wet coffee processing time, which causes a delay to obtaining the product, especially in the peak production seasons. Therefore, the use of pectinases is important to accelerate mucilage degradation and improve the efficiency in this stage. However, the effects by application in concentrations lower than those recommended and the recycling of the fluids obtained to new batches of coffee, are unknown in the coffee fermentation process and the quality of the beverage. To determine this effect, a Random Block experimental Design was conducted in a 2x3 + 1 factorial arrangement, with two levels of enzyme concentrations and three application cycles, original enzyme and recirculation. The control treatment was the traditional fermentation. Anova and Tukey tests were performed when significant effect was found. Temperature in the coffee masses of the treatments, ranged between 22 and 27 °C and the pH between 5,6 and 3,5. The results indicated differences in the degradation time, which was reduced, between 79 and 85% in the first use, and between 22 and 23 % in the first re-use, compared to the control. The coffee cup quality did not show significant differences, with SCA scores varying between 81,18 and 81,80. Characteristics such as pH, viscosity and volume of the drained fluids varied according to the concentration and number of recirculations of the enzyme, obtaining a higher volume as well as lower viscosity and acidity for those resulting from the first application. The use of this pectinase is an alternative to accelerate degradation of coffee mucilage, since its use does not affect the quality. [ABSTRACT FROM AUTHOR]

Introduction: In bottled beer pasteurization process simulation, continuity, energy and momentum balances use is required, and these mathematical models in non-steady state require of density, viscosity, heat capacity and thermal conductivity values. Some researchers have used thermo physical water properties to estimate those of beer, without performing any analysis that shows that this is reliable. Objective: To validate mathematical models use to estimate the thermo physical water properties, applying statistical techniques that allow them to be compared with models, data and values reported by different authors, to be used later in bottled beer pasteurization process simulation. Materials and methods: For water properties models validation, regression analysis and hypothesis tests were used, from which comparisons between models and reported values were made. Results and Discussion: When comparing means between obtained by models water properties with those obtained by other authors, probability values greater than 0.05 are obtained, so null hypothesis, Ho, is not rejected. So there are no statistically significant differences between analyzed values. Conclusions: It is proposed to use corresponding to water models in beer thermo physical properties estimation, in pasteurization process temperature range, in future simulation studies. [ABSTRACT FROM AUTHOR]

El objetivo de este estudio fue evaluar diferentes mezclas del biodiésel extraído de Jatropha curcas (L.) en bancos de motores diésel, para su posterior uso en el transporte agrícola en Cuba. Para ello, se prepararon mezclas del combustible diésel con 5, 10, 15 y 20 % de este biocombustible. Se evaluaron las prestaciones en motores, las emisiones de gases contaminantes y los parámetros de la combustión; asimismo, se definió hasta qué contenido de biodiésel se puede llegar en la mezcla combustible. Entre los resultados más importantes, se evidenció un incremento en el consumo específico de combustible a medida que se aumentó el porcentaje de biodiésel en la mezcla y la presión en la cámara de combustión; así como una disminución del tiempo de retardo de la ignición, debido al mayor número de cetano del biodiésel comparado con el diésel. En el caso del sistema de inyección de combustible, se registró un aumento de la presión de inyección al emplear biodiésel. Se evidenció una reducción de las emisiones de CO, NOx y CO2 cuando se mezcló hasta el 20 %, por lo que se considera que este es un porcentaje adecuado, aunque es necesario realizar las pruebas de durabilidad del motor.

Objetivos. Evaluar el efecto del endospermo de semilla de tara (EST) y polvo de hojas del Agave americana (HAA) sobre el peso corporal y velocidad de tránsito intestinal en ratas Holtzman. Materiales y métodos. Veinticinco ratas machos Holtzman distribuidas en cinco grupos y alojadas en jaulas individuales, fueron alimentadas durante 21 días con uno de los siguientes tratamientos: T1, dieta con 6% de alfa celulosa (control); T2, dieta con 6% de EST; T3, dieta con 6% de HAA; T4, dieta con 10% de EST y T5, dieta con 10% de HAA. Se registraron el consumo de alimento, ganancia de peso corporal, digestibilidad aparente de la grasa, características de las heces (contenido de grasa, peso, humedad, volumen y pH) y tiempo de tránsito intestinal. Se realizaron análisis de varianza (ANOVA) de una vía y a través de la comparación múltiple de medias de Tukey. Resultados. Dietas con 6% y 10% del EST exhibieron una reducción en el consumo de alimento, digestibilidad aparente de la grasa y pH fecal, cuyos resultados tuvieron efectos en la reducción de la ganancia del peso corporal de 37,0% (p=0,008) y 50,9% (p=0,001) comparados con la dieta control. Dieta con 10% del polvo de HAA redujo el tiempo de tránsito intestinal de 642 min (control) a 532 min (p=0,242). Conclusiones. Dietas que contienen EST regulan la ganancia del peso corporal; en cambio, dieta con polvo de HAA, no tuvo efectos sobre la velocidad de tránsito intestinal en ratas.

El objetivo de la investigación fue evaluar la incidencia de porcentajes de goma guar y zumo de maracuyá (Passiflora edulis) en la calidad fisicoquímica y organoléptica del néctar para establecer la formulación idónea; se utilizó un diseño completamente al azar (DCA) en arreglo bifactorial A*B (3*2) con tres replicas por tratamiento, como factores se utilizaron factor A porcentajes de goma con 3 niveles (0,2%; 0,3%; 0,4%), para el B porcentajes de zumo de maracuyá se utilizaron 2 niveles (15%; 20%), se evaluaron los parámetros viscosidad, densidad, pH, sensorial, proteína, lípidos, carbohidratos y microbiológicos. Los resultados demostraron que el factor A fue estadísticamente significativo para las variables pH y viscosidad más no en densidad, el factor B no fue estadísticamente significativo. El mejor tratamiento fue T4 (0,3% de goma guar y 20% de zumo) con valores de pH 3,4; viscosidad 42 Cps y densidad 1,07 g/cm3, microbiológicamente cumplió lo establecido en la Norma INEN 2337-2008, sensorialmente fue el de mayor aceptación por los panelistas; el atributo sabor no se ve influenciado por la goma utilizada ya que el análisis con el estadístico no paramétrico de Kruskal Wallis al 5% no presenta diferencia significativa.

Adhesivos para madera como la urea-formaldehído y el fenol-formaldehído son apreciados por su eficacia y el segundo ofrece buena resistencia para usos en ambientes húmedos. Su inconveniente son las emisiones de formaldehído, que en estudios recientes se ha comprobado son nocivos para la salud. El objetivo general del presente trabajo fue desarrollar un adhesivo para madera a partir de proteína de soya y adición de furfural para incrementar su capacidad y hacerlo amigable con el ambiente. Se prepararon diversas formulaciones de proteína de soya-furfural en agua a concentraciones de adhesivo de 10 %,15 % y 20 % y adiciones de furfural base seca de 0 %, 15 %, 25 % y 35 %. La capacidad adhesiva de cada formulación se determinó en ensayo de tensión acorde a la norma ASTM-D 2339-98, mediante probetas de chapas encoladas de pino, a las que se les aplicó una capa uniforme del adhesivo soya-furfural y prensado a 1 MPa, a 150 °C, durante 5 minutos para su curado. Asimismo, se elaboraron y probaron especímenes encolados con urea-formaldehído. Los resultados de resistencia a la tensión fueron de 1.6 a 1.8 MPa sin furfural de 2.5 MPa, con adición de 25 % de furfural a una concentración de 10 %, y a 1.7 MPa con la resina urea-formaldehído. Se concluye que la adición de furfural a la proteína de soya incrementó su resistencia adhesiva, además tuvo mejor desempeño que la resina urea-formaldehído, lo cual permite visualizar su aplicación en la manufactura de tableros.

Xanthan gum is used in the oil industry for the tertiary extraction of petroleum. In its use in the basin of the Gulf of San Jorge, there were problems with the loss of gum structure. Strain identified by Bacillus pumilus was isolated from oil water industry and was grown in the medium with xanthan as carbon source. This change modifies the viscosity of the gum and thus changing its properties.

The mixing of products in the manufacture of food in general and feed in particular for animals, constitutes a key phase for the dosage of the food and the nutrition, having a significant effect on the uniformity of the mixture, the functional properties and the sensory characteristics of the food. The objective of the work was to develop a review of current technologies, as well as the most important research aimed at mixing products, for the manufacture of feed and conglomerates. During the analysis, it is exposed that the components of a mixing operation can be: dry foods and / or low, medium and high viscosity liquid foods, processed with horizontal and vertical axis mixers respectively. The uniformity of the final product depends on the type of mixer used, the mixing conditions such as speed, temperature, and time, as well as the composition of the food. In the case of dry food, it is highlighted that each ingredient has physical properties that affect its ability to be mixed with other ingredients, such as: grain size, density, shape and surface characteristics, hygroscopicity, adhesiveness and susceptibility to electrostatic charges. In researches carried out it was shown that the granulometry constitutes the most influential factor on the homogeneous mixing of dry food and as it increases its size, more time is required to obtain said mixing. [ABSTRACT FROM AUTHOR]

In this paper, a two-dimensional sliding block model --discretized in slices- is presented, in which the geometrical, mechanical and rheological variables of the landslide are considered in order to analyse the soil landslide kinematic behaviour. The movement of the sliding mass is presented as a system of adjacent blocks; the movement strength is given by the Coulombviscous rheological model, where the friction and viscous components are considered, represented by a parallel system of a slider and a damper, respectively. The movement equation of the model corresponds to a second order differential equation, which was solved by the finite difference method, obtaining an explicit equation to know the displacement, velocity and acceleration of each block. An algorithm was developed in MATLAB® software, where movement equations were programmed to obtain results of the sliding kinematics. With the algorithm developed it was possible to make a sensitivity analysis to the parameters of the model. This was implemented in the problem of the sliding block at infinity slope, where it was possible to know the influence of each of the parameters of the model. The model has also been applied to the Hiegaesi landslide occurred in Japan in 1998, where the kinematic behaviour has been analysed in the model, regarding the records reported. However, further research is needed in order to apply the published model for prediction of the kinematic behaviour of landslides due to different limitations discussed in this paper. [ABSTRACT FROM AUTHOR]

La melaza se comporta como un fluido no newtoniano, es decir: no existe una relación constante entre el esfuerzo y la velocidad de rotación debido a características propias de su composición (contenido de gomas, polisacáridos, etc.); por ello, la determinación directa de viscosidad aparente no arroja un valor confiable. El cálculo de la viscosidad de un fluido no newtoniano involucra los parámetros de índice de flujo (n) e índice de consistencia (K). El objetivo de este trabajo fue realizar mediciones de viscosidad aparente y el cálculo de la viscosidad real como fluido no newtoniano. Se evaluaron ocho muestras de melaza de distintos ingenios de la provincia de Tucumán recolectadas durante la zafra 2015. Los resultados de viscosidad real se encontraron en un rango de 22,26 a 213,34 [Pa.s] y se comparo esta con la viscosidad aparente, con un error relativo que varía entre 6,09% a 51,02%. Se puede concluir que la metodología propuesta resulta útil para el cálculo de viscosidad real en melazas de ingenios de Tucumán, corroborando el comportamiento no newtoniano de este tipo de fluido.