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El presente estudio experimental aborda el impacto del tipo de emisor de información en la percepción de credibilidad de las noticias tecnológicas. La investigación involucró a 150 estudiantes universitarios, quienes, mediante un diseño entre sujetos 3 x 1, observaron un video sobre un innovador invento médico. La variable principal fue el emisor de la noticia: un presentador humano, un avatar con alto grado de realismo humano y un avatar de apariencia ficticia. La evaluación se centró en la credibilidad de la información. A través de análisis de la varianza (Anovas) y pruebas post-hoc se descubrió una jerarquía clara en la percepción de credibilidad. Los datos revelaron que existen diferencias estadísticamente significativas en la credibilidad otorgada a la condición humana y a la del avatar realista, a favor del humano. Sin embargo, no se hallaron diferencias significativas entre el humano y el avatar ficticio. Esto sugiere que la apariencia no humana de un avatar no necesariamente disminuye la credibilidad frente a una persona real, aunque los avatares muy realistas pueden generar cierto rechazo que se puede traducir en una menor credibilidad percibida.

En la actualidad persiste la necesidad de implementar estrategias que permitan combinar la teoría con la práctica, trascender de la clase magistral y lograr que el estudiante comprenda la utilidad del conocimiento adquirido. Una alternativa son los proyectos de aula que permiten la inclusión de la formación investigativa, la generación de espacios de dialogo y el trabajo en equipo. En este documento se socializa la experiencia de haber implementado proyectos de aula que consistían en el desarrollo de experimentos en condiciones de módulos didácticos aplicando la temática de la asignatura de Diseño Experimental del programa Ingeniería Pecuaria e Ingeniería Agronómica de la Universidad Francisco de Paula Santander Cúcuta. Se resaltan algunos de los proyectos exitosos y no viables, el análisis de los datos registrados a partir del experimento más representativo (módulo de un cultivo de arroz en bloques al azar balanceado) y finalmente el análisis de la percepción de algunos de los estudiantes que participaron en los proyectos. Los resultados son prometedores para continuar implementando esta estrategia didáctica en los procesos de enseñanza.

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica 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.)

Los resultados arqueométricos (espectroscopía Raman y difracción de rayos X) obtenidos a partir del desarrollo de un trabajo interdisciplinario entre arqueólogas, físicas y químicas indican que se empleó el mismo compuesto de base (hematita: α-Fe2O3) para lograr las pinturas rojas y generar la amplia paleta de tonalidades presentes en los baños y diseños de piezas cerámicas que circularon entre los siglos I y XVI de la era en las regiones de Fiambalá y Chaschuil. Estos resultados generaron una serie de interrogantes que derivaron en la preparación de un diseño experimental para evaluar si la temperatura máxima de cocción generaba cambios en la composición química de las pinturas y en la tonalidad obtenida. La experimentación se desarrolló bajo condiciones controladas de observación, registro y análisis en dos etapas que difirieron fundamentalmente en la forma de cocción: (i) mufla eléctrica y (ii) horno de barro de tiro directo. En función de los primeros resultados obtenidos, introdujimos una serie de variantes dentro de cada una de estas etapas a fin de evaluar el rol del tiempo de cocción sostenido a cada temperatura y la incorporación de ligantes orgánicos en las recetas. Los resultados indican la presencia de hematita como causa de los tonos rojos. No se detectaron modificaciones químicas de importancia entre los pigmentos cocidos a 750 o a 900 ºC ni entre los que permanecieron a dichas temperaturas durante lapsos entre 0 y 20 minutos. Los ligantes no tuvieron impacto en la composición ni en las tonalidades obtenidas.

Copyright of Revista del Museo de Antropología is the property of Museo de Antropologia - IDACOR 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 article presents the experience of implementing classroom projects based on the design of agricultural experiments in the teaching and learning process. Successful and unviable projects are highlighted, as well as data analysis and student perception. The results are promising for continuing to implement this teaching strategy. The importance of proper planning, communication between teachers and students, student commitment, and resource availability are also discussed. [Extracted from the article]

Copyright of Cuadernos.info is the property of Pontificia Universidad Catolica de Chile, Facultad de Comunicaciones 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 Dilemas Contemporáneos: Educación, Política y Valores is the property of Dilemas Contemporaneos: Educacion, Politica y Valores 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 Revista Cientifica de la Facultade de Veterinaria is the property of Universidad del Zulia, Facultad de Ciencias Veterinarias 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 evaluar el efecto del empleo de nuez pecana, fibra de trigo y carne bovina obtenida de toretes engordados bajo un sistema silvopastoril intensivo (SSPi), sobre las propiedades fisicoquímicas, microbiológicas y sensoriales de hamburguesas. Mediante un diseño de mezclas se obtuvo la mejor formulación de la hamburguesa empleando como variables independientes los porcentajes de carne de toretes engordados bajo un sistema tradicional (ST), nuez pecana, fibra de trigo, aditivos y mezcla de vegetales, considerando como variables de respuesta el color, sabor, olor, textura y contenido de grasa. La mejor formulación obtenida del diseño fue replicada empleando carne de vacuno SSPi y se elaboró además una tercera formulación control con carne ST y sustituyendo la nuez y la fibra por grasa bovina. A las formulaciones resultantes se les realizó controles físico–químicos, perfil de ácidos grasos, análisis microbiológicos y evaluación sensorial mediante análisis cuantitativo descriptivo. La mejor formulación sugerida por el diseño estuvo compuesta por 65,7 % de carne ST: 11,1 % de nuez pecana; 1,1 % de fibra de trigo; 6,1 % de aditivos y 16 % de mezcla de vegetales. Las formulaciones elaboradas con adición de nuez y fibras (HST y HSSPi) resultaron significativamente superiores desde el punto de vista físico–químico y sensorial a la hamburguesa control (HC), con menores porcentajes de grasa, mejores propiedades de cocción y mayores contenidos en ácidos grasos poliinsaturados, así como una mejor aceptación sensorial, destacándose significativamente en estos parámetros la formulación elaborada con carne SSPi. Desde el punto de vista microbiológico no se encontraron diferencias significativas y todos los productos resultaron microbiológicamente aceptables cumpliendo con los parámetros establecidos en las normas.

Introducción. El lactosuero es el residuo líquido obtenido de la fabricación de quesos con valor nutricional aprovechable. Contiene el 95 % de la lactosa, 25 % de las proteínas y 8 % de la materia grasa del total de componentes de la leche. Objetivo. Elaborar una bebida refrescante de suero lácteo con la adición de harina de arroz y concentrado de naranja. Materiales y métodos. El trabajo experimental se desarrolló en los laboratorios del Departamento de Alimentos del Instituto de Farmacia y Alimentos de la Universidad de La Habana-Cuba, entre enero y mayo de 2021. Se caracterizaron las materias primas: lactosuero, harina de arroz y jugo concentrado de naranja. Se aplicó un diseño de mezcla con base en el programa Design–expert versión 8.0, para seleccionar la mejor formulación (combinación de ingredientes). Las variables independientes en porcentaje fueron: suero (79, 95 a 84,15), jugo concentrado de naranja (7 a 11) y estabilizante goma guar (de 0,1 a 0,3) y como variables de respuesta aceptabilidad y estabilidad de la bebida obtenida. La mejor combinación de ingredientes fue evaluada por un panel de jueces con base en la intensidad de los atributos olor, sabor a naranja y consistencia, mediante los atributos “ligero”, “moderado” y “marcado”. Resultados. La mejor formulación estuvo compuesta por suero (84,15 %), concentrado de naranja (7 %), azúcar refino (5 %), harina de arroz (3,75 %) y estabilizante goma guar (0,1 %). Los catadores otorgaron a la bebida la evaluación integral de “me gusta”, según sus criteros la intensidad del olor a naranja fue ligero y moderado, el sabor a naranja moderado y la consistencia ligera. Conclusión. Todas las formulaciones ensayadas mostraron buena estabilidad y aceptabilidad sensorial adecuada. La mejor combinación no presentó separación de fases a las 24 horas de elaborada y fue caracterizada por veinte catadores.

The sawing of Hymenaea courbaril is complex due to its high density and abrasiveness. These factors accelerate the wear on saw blade teeth, and as a consequence, increase the cutting variability and process costs. The effect of cutting parameters on standard deviation of sawn-wood thickness was evaluated to propose optimal sawing conditions. A log carriage bandsaw with two saw blade geometries, three log diameter classes, and two feed rates were used to carry out the sawing tests. The results showed that the sawing variation expressed by the total standard deviation of board thickness was lower than 1 mm, when log diameter was lower than 0.79 m, and the log carriage feed rate was lower than or equal to 10 m min-1 for both saw geometries. The sawing thickness was affected by log diameter and log carriage feed rate, while saw geometry was not statistically significant. However, the goal of this initiative was not an estimation of the changes on sawmill productivity. Before this study, all log classes were processed with a log carriage feed rate of no higher than 10 m min-1. Consequently, given the estimated total standard deviations, it can be suggested that the logs of class 2 could be sawn at a 50 % higher rate without altering the cutting precision, improving sawmill productivity. [ABSTRACT FROM AUTHOR]

Copyright of Revista CIENCIA UNEMI is the property of Universidad Estatal de Milagro (UNEMI) 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.)

Research is the basis for the development of ecological restoration strategies and, therefore, bears the responsibility for the frequent failure of this practice. Experimental research is considered one of the most powerful tools to establish the causality of an ecological phenomenon and to provide relevant information in terms of ecosystem management. In this work, a review of the specific scientific knowledge on ecological restoration of Andean and high Andean forests was carried out in order to perform an analysis based on bibliometric indicators of importance (Price index, Isolation index and Collaboration index) and scientific impact (Immediacy index and Impact index of publications) to identify information gaps regarding experimental research. A total of 186 documents were analyzed, including scientific articles, technical papers, books, book sections and graduate theses. In general, experimental research in terms of ecological restoration in Andean and high Andean forests is only used in 17% of the research, with a special emphasis on the study of flora. The largest information gaps, derived from experimental research, are found in the fields of agroecology, socioeconomics and multi-thematic or multidisciplinary studies. Most of the experimental research corresponds to technical documents or degree theses with partial or unpublished results, so the potential for generating knowledge in ecological restoration is high if the investigations are completed and carried out with sufficient scientific rigor. [ABSTRACT FROM AUTHOR]

Copyright of Perspectiva Educacional is the property of Perspectiva Educacional 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 main disadvantage of using biodiesel is its price, which is due to high costs of raw material and oil conditioning to obtain biodiesel by conventional transesterification, which prevents it from competing with fossil fuels. An alternative method was investigated to obtain biodiesel by in-situ transesterification or reactive extraction (RE) from Jatropha Curcas L. seeds. This alternative process seeks to reduce stages in the production process, and thus, reduce operational costs with respect to the conventional method. The influence of temperature, catalyst mass concentration (g NaOH/g oil), and methanol to oil molar ratio, in order to maximize yield and FAME concentration of biodiesel obtained, was determined through a central composite design (DCC) with response surface methodology. The most appropriate conditions to obtain biodiesel by in-situ transesterification occur at 44°C, with a mass concentration of catalyst 1,2 g NaOH/100 g oil, and with a methanol to molar ratio of 135:1 with the presence of hexane, keeping constant stirring speed (635 rpm) and reaction time (3h). In these conditions, a yield of 71,99% w/w (g biodiesel/g oil) and a FAME content of 90,36% w/w (g FAME/g biodiesel) were reached. The results of this study provide an alternative process for obtaining biodiesel without the need of extraction and pretreatment stages employed in the traditional method, in addition to reducing excess washes in the conventional process, which increase process costs and environmental impact. [ABSTRACT FROM AUTHOR]

Introduction: Typically, research on dung beetles in the Tropical Dry Forests (TDF) of Colombian Caribbean region, have applied methodologies designed for wet or Andean areas of the country, which could be influencing the performance and efficiency of sampling. Objective: In order to contribute to this discussion, we analyzed how the bait amount and pitfall trap operating time influence the collection effectiveness of dung beetles in a TDF fragment at Reserva Campesina La Flecha, San Jacinto, Colombia. Methods: For the collection of beetles, we utilized pitfall traps baited with three different amounts of attractants: small (34.6 g), medium (53.8 g), and large (114.9 g), which remained active in the field for 48 h., 4 samplings between March and September 2015 were carried out, covering both, dry and rainy seasons. Results: A total of 4 563 individuals were recorded, grouped into 10 genera and 27 species of dung beetles. The highest values of richness, abundance and biomass were registered in the large bait, at 48 h, during the rainy season. However, the trap operating time had no effect on the estimation of beetles’ richness, abundance, and biomass, regardless of bait sizes. The three diversity orders (0D, ¹D y ²D) showed similar values between the bait amounts during rainy season, but in the dry season, the largest baits displayed the highest diversity values. On the other hand, with the largest bait, significantly more richness, abundance, and biomass of small and large body beetles were registered, especially during the dry season. Conclusions: The results of this research show that, for the study of beetles’ assemblages in the BST, the use of a larger bait contributes to a better estimate of richness, abundance, diversity and biomass, especially during the dry season, when environmental conditions promote a more rapidly loss of baits attractiveness. [ABSTRACT FROM AUTHOR]

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 Estudios Gerenciales is the property of Universidad ICESI 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.)

Due to its fast and economical execution, the geotechnical solution known as soil nailing walls is widely used for the stabilization of slopes and ground excavations. At the design stage, verification of the external stability of the soil nailing wall is one of the most important acceptability criteria. The main objective of this work is to evaluate the external stability of soil nailing walls, considering the variability influence of their height and the geomechanical parameters of the soil in-situ. The probabilistic 2k factorial design methodology has been applied to generate 32 experiments. A vertical soil nailing wall, with variable height, under pseudo-static load conditions, and executed in residual soil from granitic rock has been used as a prototype model. Based on the analysis of the observations of the 32 experiments, three regression models have been developed, which can be used to predict the value of the factors of safety with arbitrary realizations. Furthermore, the observations show that the factors that most influence the external stability of soil nailing walls are the height of the wall, the cohesion and the friction angle of the soil in-situ. [ABSTRACT FROM AUTHOR]

The objective was to estimate the optimal plot size for field experiments with the common bean (Phaseolus vulgaris L.) using the modified maximum curvature method. A uniformity trial was carried out with the cultivar BRSFC-402 sown at a spacing of 0.5 m between plant rows and 10 plants per meter within the row. Final bean stand, mean number of pods per plant, mean number of grain per pod, mean 100-grain weight, and grain yield were evaluated. Measurement were taken from 20 central rows measuring 20 m in length, totaling 4,000 plants on an area of 200 m2. A basic unit (0.5 m2) was a row containing 10 plants. Four hundred basic units were combined to form 14 plot shapes. The methods relative information and modified maximum curvature were used to define the optimal shape and size of plots, respectively, for experimental evaluation with the common bean. As the plot should be suitable for efficient evaluation of all evaluated characteristics, the optimal plot size consisted of five basic units (25 plants) and was shaped as five rows x one basic unit per row. [ABSTRACT FROM AUTHOR]

The purpose of this study was to identify the ideal sample size to represent the potential of a sugarcane family for identification of superior families, and, at the same time, determine which spatial arrangement may provide better phenotypic expression of the progeny of the sugarcane families tested. Thus, five full-sib families, each with 360 individuals, were evaluated in a randomized block design with three replications. The plants were placed in three different spatial arrangements in the row: 50 cm, 75 cm, and 100 cm between plants; with 150 cm between the rows. The bootstrap method was adopted to determine the ideal sample size, as well as the best spacing for evaluation. The 100-cm spacing provided the best mean values for number of stalks, mean stalk diameter, and estimated weight of stalks in the stool. The 75-cm spacing between plants within the row allowed better discrimination among the families for all the traits evaluated. At the 75-cm plant spacing, it was also possible to identify superior families with a sample of 30 plants from each plot and 3 reps in the trial. [ABSTRACT FROM AUTHOR]

The aim of this work was to determine the most suitable conditions for osmotic dehydration as a pre-treatment to drying, to obtain dehydrated pineapple, for incorporation into fermented milk. For the research, an experiment design 32 was carried out using three temperatures (30, 40 and 50 °C) and three concentrations of sucrose syrup (55, 60 and 65 °Brix) taking as response variables: gain in solids, loss of water and weight loss. The best variant was selected considering the greatest water loss, resulting in the most appropriate treatment when the sucrose syrup has 65 °Brix and the temperature is 50 °C, under these conditions the water loss was 62.5%. [ABSTRACT FROM AUTHOR]

Increasing global energy demand is fostering the development of renewable energy as an alternative to fossil fuels. However, renewable energy facilities may adversely affect wildlife. Facility siting guidelines recommend or require project developers complete pre‐ and postconstruction wildlife surveys to predict risk and estimate effects of proposed projects. Despite this, there are no published studies that have quantified the types of surveys used or how survey types are standardized within and across facilities. We evaluated 628 peer‐reviewed publications, unpublished reports, and citations, and we analyzed data from 525 of these sources (203 facilities: 193 wind and 10 solar) in the United States and Canada to determine the frequency of pre‐ and postconstruction surveys and whether that frequency changed over time; frequency of studies explicitly designed to allow before‐after or impact‐control analyses; and what types of survey data were collected during pre‐ and postconstruction periods and how those data types were standardized across periods and among facilities. Within our data set, postconstruction monitoring for wildlife fatalities and habitat use was a standard practice (n = 446 reports), but preconstruction estimation of baseline wildlife habitat use and mortality was less frequently reported (n = 84). Only 22% (n = 45) of the 203 facilities provided data from both pre‐ and postconstruction, and 29% (n = 59) had experimental study designs. Of 108 facilities at which habitat‐use surveys were conducted, only 3% estimated of detection probability. Thus, the available data generally preclude comparison of biological data across construction periods and among facilities. Use of experimental study designs and following similar field protocols would improve the knowledge of how renewable energy affects wildlife. Article Impact Statement Many surveys at wind and solar facilities provide limited information on wildlife use and fatality rates. [ABSTRACT FROM AUTHOR]

This study focused on obtaining an optimal spaghetti-type paste from quinoa flour (60–75%), cassava starch (1.5–5.0%) and water (25–40%) as variable factors and as a fixed egg-white factor (9%). In order to obtain a paste with the highest percentage of protein, the response surface methodology (MSR) with Box–Behnken was used. In addition, the effect of the composition on textural, rheological, and sensory properties was evaluated. Among the most outstanding results, the R2 value indicates that the predictive model explains the 76.33% protein variability. The optimal conditions for quinoa flour, cassava flour, and water were 60%, 1.5%, and 35.28%, respectively. It was shown that the quinoa flour content affects the rheological properties, storage modulus, G', is greater than the loss modulus, G", in agreement with the maximum breaking force obtained in pasta, indicating behavior more elastic than viscous with good bonding characteristics and dense internal structure. Finally, the application of the experimental design permitted finding the pasta's optimal composition and analyzing the sensory profile by verifying all its attributes; the results obtained indicated that it is possible to prepare a gluten-free pasta with acceptable texture, flavor, and color for the consumer. [ABSTRACT FROM AUTHOR]

Ecoacoustic approaches have the potential to provide rapid biodiversity assessments and avoid costly fieldwork. Their use in biodiversity studies for improving management and conservation of natural landscapes has grown considerably in recent years. Standardised methods for sampling acoustic information that deliver reliable and consistent results within and between ecosystems are still lacking. Sampling frequency and duration are particularly important considerations because shorter, intermittent recordings mean recorder batteries last longer and data processing is less computationally intensive, but a smaller proportion of the available soundscape is sampled. Here, we compare acoustic indices and processing time for subsamples of increasing duration clipped from 94 one-hour recordings, to test how different acoustic indices behave, in order to identify the minimum sample length required. Our results suggest that short recordings distributed across the survey period accurately represent acoustic patterns, while optimizing data collection and processing. ACI and H are the most stable indices, showing an ideal sampling schedule of ten 1-minute samples in an hour. Although ADI, AEI and NDSI well represent acoustic patterns under the same sampling schedule, these are more robust under continuous recording formats. Such targeted subsampling could greatly reduce data storage and computational power requirements in large-scale and long-term projects. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Estudios Políticos is the property of Centro de Estudios Politicos y Constitucionales 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.)

BACKGROUND: Weight excess (WE) relates to health disorders in children and adolescents and can deteriorate their health-related quality of life (HRQoL). OBJECTIVE: Longitudinally assess health-related quality of life in subjects from 7 to 17 years of age with excess weight, treated with two different schedules of medical care: comprehensive and traditional. MATERIALS AND METHODS: Quasi-experimental design with 42 subjects and their parents or care takers, stratified by the type of intervention; group I received a comprehensive intervention, while group II, an intervention based on traditional nutritional care. The subjects were compared using the BMI-Z score for age and sex, and the validated Peds- QL® questionnaire was used to examine their HRQoL before and after an intervention for weight control. The association between BMI and HRQOL was estimated using a multiple linear regression model. RESULTS: At baseline, there were no differences in body condition and HRQoL of both groups. After the intervention, the subjects in group II had 12 points less (p = 0.012) in the PedsQL® score than those in group I. CONCLUSIONS: The HRQoL of subjects with the traditional intervention was perceived as deteriorated, while the comprehensive program for weight control had a positive effect on their HRQoL. [ABSTRACT FROM AUTHOR]

Impulsivity and risk taking are positively associated with alcohol consumption. Likewise, impulsivity and risk taking increase after acute alcohol intake. Objective. Examine the effect of a dose of alcohol (0.6/0.7 g/kg women and men) on performance in inhibitory control tests, sensitivity to rewards and risk taking in students with high (IMP+) and low (IMP-) trait impulsivity. Method. Participants (n= 85, 43 women, between 21-27 years) completed the BART, GoStop and SKIP tasks before and after the ingestion of an alcoholic beverage or a placebo beverage. Results. The results show an increase, induced by alcohol, in risk taking in women and greater failures in the inhibitory control after alcohol intake, especially in men. The hypothesis about greater behavioral impulsivity among those exhibiting greater trait impulsivity was partially corroborated. Conclusions. The main finding of this work lies in the increase, induced by alcohol, of impulsivity and risk taking, and the modulating effect of sex on this effect. [ABSTRACT FROM AUTHOR]

Background: The determination of polyphenols in cocoa beans allows the establishing of antioxidant properties of great benefit to this product. Objectives: Optimization of the ultrasound-assisted extraction method to determine the content of polyphenols in cocoa beans. Methods: Two experiments design stages were carried out to optimize the ultrasound-assisted extraction process of polyphenols from the cocoa bean. In the first experiment design stage, the adequate extraction solvent was determined; for this purpose, five types of solvents were evaluated through a completely random design unrestricted (CRD). In the second experiment stage, a central composite design 22 + star point (with two central points) was used, which was evaluated using the response surface methodology to determine the influence of the temperature, time, and solute / solvent ratio. Results: The experiment found that acetone: water: acetic acid (70: 29.5: 0.5) mixturee, leads to a greater amount of total extracted phenols measured for the Folin- Ciocalteu method. Analysis of variance (ANOVA) found that six significant effects that influence the response variable (total phenols extracted). The main effects were of the three factors and three of their interactions. Conclusions: After the optimizing said factors, an optimal point was found: 39.3 ° C of temperature, 74.5 minutes, and 22.8 mL of solvent per gram of cocoa sample. [ABSTRACT FROM AUTHOR]

Copyright of Comunicaciones en Estadística is the property of Universidad Santo Tomas 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 estimar los beneficios económicos potenciales por una mejora integral en la provisión de servicios de saneamiento básico (agua, alcantarillado y tratamiento) mediante el experimento de elección (EE) con modelos logit multinomial y logit mixto. Se realizaron 392 encuestas a usuarios de los servicios de saneamiento básico en la ciudad de Puno. Mediante el modelo logit mixto-dummy codes se estimó una disposición a pagar marginal (DAPM) agregada de S/9.95/mes/vivienda. Con base en el modelo logit multinomial-effect codes, se logró estimar la variación compensatoria (VC) en S/9.11/mes/vivienda. Al comparar ambos resultados, se concluye que no existen diferencias significativas, por lo tanto, cualquiera de estas medidas monetarias de bienestar, al ser agregado en función a la población potencialmente beneficiaria por el cambio, se podría utilizar como medida de beneficio económico en la evaluación costo/beneficio de las mejoras planteadas. Así mismo se ha evidenciado que el atributo “tratamiento” en más valorada que los atributos “agua” y “alcantarillado”, por lo tanto, cualquier política orientada a mejorar los servicios de saneamiento básico en la ciudad de Puno debe estar prioritariamente focalizada a solucionar el tratamiento de aguas residuales. La elección de alternativas de mejora en los servicios de saneamiento básico está condicionada por el nivel educativo y el ingreso monetario mensual de los usuarios.

La aplicación de conceptos matemáticos y la generación de soluciones matemáticas a problemas de ingeniería son esenciales para la enseñanza de todos los estudiantes de grado de ingeniería. Como la ingeniería es una profesión de carácter eminentemente práctico, los enfoques multidisciplinares para experimentación de laboratorio pueden conducir a un mejor aprendizaje para los alumnos. En este trabajo se descríbela aplicación de metodologías de superficie de respuesta (RSM) para un curso de Ingeniería Química. En particular, el documento considera la aplicación de un diseño experimental empleando software científico como Statgraphics para simular la gestión de efluentes contaminados procedentes de las industrias, para que los estudiantes relacionen el “mundo real” con los conceptos más teóricos impartidos en el aula. Las principales competencias de laboratorio desarrolladas en este curso serán el trabajo por proyectos y la propuesta de soluciones, la comunicación y el trabajo en equipo.

Esta investigación evalúa el nivel de aceptación de un nuevo tipo de canastitas de relleno confeccionadas a base de maíz. Se utiliza un diseño de bloques completos al azar en donde los tratamientos están representados por distintos tipos de mezclas de maíz y los bloques están representados por los individuos. Se encontró que no hay diferencia significativa en el nivel de aceptación con respecto al sabor de cada mezcla, al 5% de significancia. Igualmente se encontró, en el análisis de bloque, que los individuos no causan un efecto significante en el diseño experimental por lo que, para futuros experimentos se recomienda utilizar un diseño completo al azar.

El rendimiento de aceite por unidad de superficie es el principal criterio de selección de la mayoría de los programas de mejoramiento de girasol. Los ensayos comparativos de rendimiento instalados en red en la región girasolera de la República Argentina contribuyen tanto a la toma de decisión de los productores y asesores como a la selección de genotipos superiores por parte de los tomejoradores. El objetivo de este trabajo es cuantificar las diferencias en capacidad predictiva de diferentes diseños experim entales y métodos de análisis estadístico en la estimación de los efectos genotípicos para rendimiento de aceite (kg ha -1 ) y su impacto en la selección de híbridos superiores. Se evaluaron 43 ensayos multiambientales de girasol (261 ensayos locales) en cinco campañas. Se comparó la eficiencia relativa del diseño más frecuente en programas de mejoramiento (Bloques Completos Aleatorizados) con otros dos modelos de diseño y análisis de ensayos: Láttice y Espacial. Se obtuvo un ranking de híbridos para cada modelo y con una presión de selección del 20% se evaluó el grado de superposición en la selección entre pares de modelos mediante un coeficiente de coincidencia. El modelo espacial fue el que mejor ajustó los rendimientos de aceite obtenidos a los esperados y también presentó un aumento en la eficiencia de selección de genotipos superiores en relación con el diseño en bloques a través de un mayor coeficiente de coincidencia con el modelo de mayor eficiencia relativa para cada combinación año-subregión (modelo “ideal”). Según estos resultados se podría mejorar fuertemente la precisión de las estimaciones provenientes de las redes oficiales de ensayos comparativos de rendimiento de cultivos sin aumentar la inversión de recursos en términos de número de parcelas y utilizando programas estadísticos ya disponibles.

El nitrógeno es uno de los elementos más importantes para el crecimiento de los cultivos. Su aplicación actual, usualmente como urea, implica rendimientos bajos, con más del 50% del fertilizante desaprovechado por el cultivo de interés. Varias estrategias se han desarrollado para mejorar esta eficiencia de uso, siendo los fertilizantes de liberación controlada una alternativa prometedora. En este sentido, el presente trabajo propuso el desarrollo de películas compuestas de almidón de yuca/alcohol polivinílico (PVA) incorporadas con urea como un medio para lograr su liberación controlada. De esta forma, se planteó inicialmente un diseño factorial de filtrado para determinar los factores más significativos que afectan en la capacidad de absorción de agua de las películas compuestas (variable de respuesta); los cuales fueron analizados mediante un diseño factorial 23 con tres puntos centrales. Las películas preparadas con mayores proporciones de ácido cítrico (plastificante) resultaron en una menor capacidad de absorción de agua independientemente de la cantidad de urea utilizada. La cantidad de glicerol, alcohol polivinílico y almidón no ejercieron un efecto significativo en las condiciones empleadas. Se buscaron las condiciones que dieron lugar a la menor capacidad de absorción de agua dado que se relaciona con una liberación más lenta de la urea incorporada. Una liberación más lenta de la urea podría estar en mejor sincronía con la demanda de nitrógeno del cultivo, mejorando el uso de eficiencia del mismo.

En este paper se pretende diseñar un modelo de optimización multirespuesta para un proceso de producción químico no optimizado en una entidad del clúster petroquímico colombiano. Se realiza la estimación y diagnosis de un diseño experimental tipo central compuesto. Las variables respuestas corresponden al costo global de operación y rendimiento del proceso, mientras que los factores controlables son: Temperatura (°C), Concentración del polímero (%) y Concentración de oxígeno (%). Se determinan las interacciones entre factores y la deseabilidad compuesta, cuyo valor indica que en la quinta ejecución se localiza el óptimo global de la operación.

News websites are a digital extension of newspapers whose purpose is to meet the needs of their visitors in terms of news and information. In these sites, the time a reader remains consuming content is important because a large part of its income is obtained from advertising guidelines. In the present study, it was evaluated how the type of reading device, the presence of multimedia content and the length of the articles, affect the permanence of the readers in the site. Using a sample of paid subscribers from a business news web portal, three experiments were conducted under different approaches: online, where all users went through different news articles, online, where the news article was the same for all the subjects and an offline made in a reading laboratory. From the analysis of variance, it was determined that the reading device and the presence of multimedia content can influence the time a user stays on the website. In addition, in the local experiment, it was observed that readers feel more comfortable consuming content on devices with larger screens. [ABSTRACT FROM AUTHOR]

Innovation in health care services generates the development of new initiatives. Research should focus on the development of methodologies that allow the evaluation of interventions and determine the true impact they have. The purpose of this study was to determine the social return of investment (SROI) of a health treatment. An analysis of a psychological intervention program was carried out with a design that included pre/post-treatment measures and control group. As results, a positive social impact was obtained. Each monetary unit spent offered a net social return of 2.98. In conclusion, SROI can offer information about the social impact caused by health care interventions, determining the tangible return obtained with the investment. [ABSTRACT FROM AUTHOR]