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Introducción: Las organizaciones laborales desde una perspectiva positiva, ponderan el bienestar de sus trabajadores para alcanzar el éxito. Contar con colaboradores y grupos de trabajo con capacidades de resiliencia y comprometidos con su organización, debe ser la brújula que guíe a las organizaciones que no solo busquen sobrevivir, sino hacer de ese espacio un lugar de crecimiento personal, grupal y organizacional. Compromiso y resiliencia son dos temas que han ido ganando interés en el ámbito laboral, en particular, desde la Psicología positiva. Objetivo: Caracterizar las variables resiliencia organizacional y compromiso organizacional en una instalación hotelera. Métodos: Metodología cuantitativa, diseño no experimental de tipo transversal con un alcance exploratorio y descriptivo. Se aplicó el cuestionario de compromiso organizacional de Schaufeli (2003) y el cuestionario de resiliencia organizacional Salanova y otros (2012). Resultados: Las puntuaciones más altas en cuanto al compromiso organizacional se obtuvieron en las dimensiones vigor y dedicación (4,75 y 4,70, respectivamente); la más baja también se obtuvo en la dimensión absorción (4,52). En cuanto a la resiliencia organizacional, los resultados obtenidos permiten considerarla como una organización resiliente (medias entre 4 y 5). Conclusiones: En cuanto al compromiso organizacional, este se caracteriza por el vigor y la dedicación. Se obtuvo un nivel alto de resiliencia organizacional; sin embargo, algunos indicadores como la ausencia de solvencia económica suficiente para enfrentar dificultades en la organización y la participación de los trabajadores en la toma de decisiones organizacionales, pudieran menoscabar la resiliencia organizacional en el hotel Introduction: Labor organizations, from a positive perspective, weigh the well-being of their workers to achieve success. Having collaborators and work groups, with resilience capabilities and committed to their organization, should be the compass that guides organizations that not only seek to survive, but make that space a place of personal, group and organizational growth. Commitment and resilience are two topics that have been gaining interest in the workplace, in particular, from positive psychology. Objective: To characterize the variables organizational resilience and organizational commitment in a hotel facility. Methods: A quantitative methodology and a non-experimental cross-sectional design were applied, with an exploratory and descriptive scope. The organizational commitment questionnaire of Schaufeli (2003) and the organizational resilience questionnaire of Salanova et al. (2012) were applied. Results: The highest scores regarding organizational commitment were obtained in the energy and dedication dimensions (4.75 and 4.70, respectively); the lowest was also obtained in the absorption dimension (4.52). Regarding organizational resilience, the results obtained allow it to be considered as a resilient organization (averages between 4 and 5). Conclusions: Regarding organizational commitment, it is characterized by energy and dedication. A high level of organizational resilience was obtained. However, some indicators such as the lack of sufficient economic solvency to face difficulties in the organization and the participation of workers in organizational decision-making, could undermine organizational resilience in the hotel

Safety training promotes safety at work, in particular through the use of engaging methods. This study introduces a newly developed measure of individual engagement in safety training, and aims to analyze the psychometric proprieties of the scale. The safety training engagement scale (STE) consists of five items pertaining to the trainee’s dedication and absorption in a safety training session. Two studies are carried out to analyze the validity of the scale. The first study focuses on the construct (internal) validity, to examine the scale’s internal consistency and dimensional structure. The second study seeks to provide further evidence for construct validity by testing the external validity of the scale. The sample consists of 913 (study 1) and 133 (study 2) participants in safety training programs in the field of the chemical industry who were invited to fill the STE scale after attending a safety training course. The results provide support to affirm the validity and reliability of the scale. The discussion describes the implication and the limitations of using the STE scale in practical safety training programs, and outlines recommendations for research to improve the scale’s robustness.

Abstract Cowpea is grown mainly in regions with a hot semi-arid climate, where other pulses do not develop satisfactorily. It is the 4th most produced pulse in the world, thus supplying the domestic and export markets. Following the trends of the food products market, a study was carried out to identify the best condition of the extrusion process, to transform these nutritious grains into quality expanded products and ready for consumption. The grains were decorticated and transformed into cotyledon flour. This flour was conditioned and the Evolum HT25 twin screw extruder feeder was adjusted to a rate of 7 kg h-1. A Box-Behnken 23 design was used, considering the following variables and levels: extrusion temperature from 100 °C to 140 °C (in the 7th to 10th zone), screw speed (300 to 700 rpm) and conditioning moisture from 12% to 16%. The temperature affected linearly and negatively (p ≤ 0.05) the sectional expansion index (2.65 to 7.64). The screw speed interfered linearly and positively (p ≤ 0.05) in the longitudinal (1.12 to 9.32) and volumetric (4.91 to 24.15) expansion index, and negatively with the water absorption index (3.05 to 3.86 g g-1). The screw speed (positive linear and negative quadratic), the moisture content (negative quadratic) and the interaction (positive) between the two interfered (p ≤ 0.05) in the water solubility index (25.89% to 33.85%). The hardness value (1.24 to 2.83 N) was affected (p ≤ 0.05) by screw speed (negative linear and positive quadratic), temperature (negative quadratic), moisture (positive quadratic), and interactions of moisture with temperature and screw speed. To obtain a hardness value close to that of commercial extrudates and high-water solubility, the maximum global desirability obtained was 0.81 for extrusion at 135.6 °C, 700 rpm and 12% moisture.

Introducción: La labor docente tiene un reconocido carácter estresante y un potencial impacto negativo en la salud psicológica de quienes la desempeñan. El compromiso académico es un constructo que tomado del ámbito laboral expresa la relación del estudiante con su tarea, puede constituir un predictor del desempeño estudiantil, pero esencialmente su presencia es indicador de la obtención, durante esta etapa de prácticas frente a un aula, de la adquisición de recursos personales para el afrontamiento de las demandas emocionales de la tarea y proteger el bienestar del futuro docente. Objetivo: Describir los niveles de vigor, dedicación, absorción y compromiso académico en una muestra preprofesional que simultanea el rol de estudiante y de docente frente a aula. Métodos: Se realiza un estudio descriptivo con un diseño transversal en los tres grupos docentes del 6to semestre de la Licenciatura en Educación, de la Universidad de Guanajuato, México. La muestra fue de 64 sujetos de los tres grupos, grupo A: 19, grupo B: 16 y grupo C: 29. Se utilizó la versión abreviada en 9 ítems de la Escala de Engagement Académico (UWESS-9). Resultados: Predominan valores altos de dedicación, absorción, engagement total y medios de vigor. Existen diferencias significativas entre los grupos siendo el grupo B, significativamente, el de mayor absorción y el A el de menor. Conclusiones: Los resultados apuntan a un posible desbalance entre las demandas y los recursos disminuyendo la dimensión energética pero no la actitudinal. Introduction: The teaching job has a recognized stressful character and a potential negative impact on the psychological health of those who perform it. Academic commitment is a construct that, taken from the work environment, expresses the student's relationship with his or her task. It can be a predictor of student performance, but essentially its presence is an indicator of the acquisition, during this stage of classroom practice, of personal resources to cope with the emotional demands of the task and to protect the well-being of the future teacher. Objective: To describe the levels of vigor, dedication, absorption, and academic commitment in a pre-professional sample that simultaneously plays the role of student and classroom teacher. Methods: A descriptive study with a cross-sectional design was carried out in three groups of teachers in the 6th semester of the Bachelor's Degree in Education at the University of Guanajuato, Mexico. The sample consisted of 64 subjects from the three groups, group A: 19, group B: 16, and group C: 29. The abbreviated 9-item version of the Academic Engagement Scale (UWESS-9) was used. Results: High values of dedication, absorption, total engagement, and average vigor predominated. There are significant differences between groups with group B having significantly the highest absorption and group A the lowest. Conclusions: The results point to a possible imbalance between demands and resources decreasing the energetic dimension but not the attitudinal one. ; ; vigor, dedicación; absorción; ; docentes ; student engagement; vigor, ; ; ; teachers

Research has examined the psychological benefits of fiction, particularly for socio-cognitive and interpersonal processes, but has yet to examine whether it can have an impact on individuals’ personal well-being in a natural setting over time. A longitudinal randomized control trial (RCT) using audiobooks was conducted to compare the effects of fiction (novels, short stories) and non-fiction on the well-being (subjective, eudaimonic, social) of 94 older adults from diverse urbancommunities over a six-week period. Participants chose one of four books in the condition to which they were allocated. The participants in the fiction, compared to non-fiction, conditions did not show greater improvements in any aspect ofwell-being over the study period. However, regression analysis controlling for initial levels of well-being showed that individuals who reported greater absorption in, and appreciation of, their audiobook showed greater subsequent wellbeing, particularly meaning in life, that extended beyond book completion. The findings indicate that an audiobook can have a positive enduring impact on various aspects of older adults’ well-being, but it depends on them having a personalengagement with its content, and not on its designation as fiction or non-fiction.

ABSTRACT: Improper management of weeds is one of the causes of low bean yield, as it is very susceptible to interference due to their slow initial growth. This study aimed to evaluate the influence of dayflower on grain yield and nutrient accumulation of bean cultivars. The experiment was carried out in a screened house, in 5 L pots, in a 2 x 4 factorial scheme. Factor 1 corresponded to the presence or absence of weeds, and factor 2 bean cultivars: BRS Pontal, BRS Agreste, BRS Ametista and BRS Estilo. The experiment was arranged in a completely randomized design with five replications. The coexistence of bean and weed was maintained throughout the crop cycle. Chlorophyll content, number of pods per plant, number of grains per plant, nutrients contents (N - nitrogen, P - phosphorus, K - potassium, Ca - calcium, Mg - magnesium, Mn - manganese, Fe - iron and Zn - zinc) in grains were evaluated. Competition with weeds negatively influenced chlorophyll content, number of pods, yield and N content in grains. The interaction was significant to P, Mg and Fe contents in grains, demonstrating that competition with weeds may impair allocation of these nutrients, resulting in grains of inferior nutritional quality. The cultivar BRS Agreste was more efficient to accumulate P and Mg in grains in competition with dayflower.

El objetivo de la presente investigación fue el de conocer la vida útil de frutas tropicales deshidratadas basado en un secador solar que fue diseñado y desarrollado bajo las condiciones de Calceta, cantón Bolívar de la provincia Manabí, Ecuador. Debido a las características físicas y químicas del banano, exhibidas durante el proceso de deshidratación por radiación, se contó con resultados satisfactorios, superiores a los obtenidos en frutos de mamey y piña. Por ejemplo, la humedad en banano con 80.22% bajó a 10.35%; en lo referente a la relación de proteína aumentó desde 1.27% en su estado fresco a 2.18% y en contenidos de fibras desde 0.88% en su estado fresco a un 2.41%. Los análisis microbiológicos determinaron la vida útil de los productos estimándose en 106, 109 y 174 días respectivamente para mamey, banano y piña. En cuanto a los atributos medidos según escala de la evaluación sensorial, la media de los tratamientos y sus propiedades, como dulce, aspecto, color y sabor, se puede demostrar que el banano contempla mejores atributos como color con 4.38; dulce 4.58; aspecto 4.68; y sabor 4.75. En banano, el estadístico R2 indica un 56.339% de la variabilidad en DM PL. El coeficiente de correlación es igual a 0.750593, indicando una relación moderadamente fuerte entre las variables.

Background: Plant extracts can be obtained to carry bioactive compounds, useful for prevention and treatment of different illnesses. This also supports the intake of teas as functional beverages. Nonetheless, it is incompletely known whether these extracts can act as effective sources and vehicles de phenolic compounds (phenolics/polyphenols) to reach their targets. Objective: To establish whether phytoextract ingestion modified in a sex-dependent manner the phenolic bioavailability and redox response in liver and kidney. Method: BALB/C mice ingested for a month 100 mg/Kg/d of extracts (tea-like) from Aspidosperma quebracho-blanco (AQB), Lantana grisebachii (LG) or Ilex paraguariensis (IP). Then, phenolics, peroxides and nitrites were analyzed by spectrophotometry. Also, phenolic permeation from digested and undigested extracts was evaluated in vitro with a rat jejunum-based assay. Results: Phenolic permeation depended on extract digestion. In males, IP showed a special time course of hepatic phenolics, whereas all extracts decreased renal phenolics at 15 days. Extracts induced hepatic lipoperoxides at 15 days. LG reduced renal hydroperoxides at 15 days and hepatic nitrites at 30 days, whereas AQB and IP reduced renal lipoperoxides and nitrites at 30 days. In females, extracts reduced hydroperoxides, with LG and AQB also reducing lipoperoxides. IP increased renal lipoperoxides at 30 days. Conclusion: IP was a relevant phenolic source. Sex-dependent responses were found in all variables, which should be considered to prevent misleading generalizations in phytodrug bioprospecting.

The aim of this research was to evaluate two traditional N sources (urea and ammonium sulfate) and an alternative one (sulfamoo) with increasing rates (0, 40, 80, 120 and 160 kg N ha-1, respectively) affecting aspects of upland rice crop cv. IAPAR 117. The experiment was carried out in greenhouse conditions, using a completely randomized design in 3x4 factorial scheme, with four replicates. It was evaluated the number of tillers (NT), plant mean height (PMH), dry matter of shoots (DMS), crop yield/mass of filled grains (MFG), content of N-DMS, agronomic efficiency of nitrogen (AE), mass of 100 filled grains (M100FG) and grain harvest index (GHI). The nitrogen rates application as ammonium sulfate resulted in a greater increasing of NT, DMS, MFG and N-DMS, respectively. In fact, higher agronomic efficiency obtained with urea and sulfamoo at 40 kg N. ha-1, although AE decreased within the higher rates of N, independently from the source. The M100FG and GHI were higher when sulfamoo and urea were used, although the high N supply negatively affected these two variables for all N evaluated sources.

Gold phytoextraction is a technology used to obtain this metal (Au) throughout plants. Some of the benefits of this technology are the mitigation of the environmental impact, the fact that it does not imply the constant use of pollutants, and has the ability to promote soil reclamation. The aim of this research was to determine if Brachiaria decumbens has the potential to improve soil physical properties while had achieved a gold extraction. For this purpose, Helianthus annuus and Brachiaria decumbens, were used in a completely randomized design with four replicates. To induce gold uptake, ammonium thiocyanate was applied to plants. The statistical analysis was performed using the R-Studio software. Finally, it became evident that B. decumbens is a gold extractor plant, which also improves the soil physical qualities and compared to H. annuus and present higher concentrations of gold than the latter (P

Resumen Actualmente las leyes ambientales son cada vez más rigurosas con los diagnósticos ambientales. Por lo anterior, es importante garantizar la confiabilidad de los resultados en los métodos de determinación de contaminantes. En el caso de los hidrocarburos, se usan métodos espectrofotométricos y cromatográficos, para los de fracción más pesada son empleadas técnicas gravimétricas Sin embargo, muchos trabajos discuten las diferencias en los resultados debido a las interacciones a matriz-contaminante. Con el fin de establecer herramientas básicas que permitan la adecuada determinación de los hidrocarburos presentes en suelo o agua, se llevó a cabo la determinación de hidrocarburos totales en distintos tipos de petróleo y destilados empleando un equipo Infracal TOG/TPH. Los diagramas de dispersión mostraron una tendencia logarítmica y se propuso un modelo de regresión lineal. Al analizar dicho modelo mediante el análisis Anova, resultó un p-valor menor a 2,2x10-16 y un coeficiente de determinación R=0,969, lo cual indica un ajuste satisfactorio del modelo potencia. Abstract Currently environmental laws are increasingly stringent with environmental diagnostics. Therefore, it is important ensure the reliability of results in the methods of determining contaminants. In the case of hydrocarbons, spectrophotometric and chromatographic methods are used, for heavier fraction are employed gravimetric techniques However, many papers discuss the differences in the results due to interactions matrix-pollutant. In order to establish basic tools that allow the proper determination of the hydrocarbons present in soil or water, was carried out the determination of total hydrocarbons in different types of oil and distillates using a computer Infracal TOG / TPH. Scatter plots and trend showed a logarithmic model linear regression was proposed. By analyzing the model by Anova analysis, it was a p-value less than 2,2x10-16 and a determination coefficient R = 0,969, indicating a satisfactory fit of the model output.

ABSTRACT: The knowledge on the mechanism that gives a weed resistance to a particular herbicide is essential regarding scientific, academic, and practical aspects because it determines the recommendations for prevention and management of resistance in the field. Studies on the sourgrass (Digitaria insularis) glyphosate resistance mechanism in the literature have not been conclusive. Thus, the aim of this research was to study and evaluate the putative resistance mechanisms whichgives sourgrass biotypes, the ability to survive after glyphosate application. For this, 14C-glyphosate leaf absorption and translocation were compared in the biotypes Matão (R), Campo Florido (MG), Diamantino (MT), and Iracemápolis (S) as a function of the time after its application. In addition, the possibility that the mechanism of resistance results from a mutation in the EPSPs-encoding gene was also studied. The biotypes S, R, MG, and MT absorbed similar amounts of 14C-glyphosate. The biotypes R, MG, and MT did not present differences in 14C-glyphosate translocation when compared to the biotype S. The sequencing of the EPSPs-encoding gene showed no mutation in the regions 106 and 182, which normally give resistance to glyphosate in the case of other species. No mutation in the EPSPs-encoding gene was observed. Therefore, they are not glyphosate resistance mechanisms for the evaluated biotypes.

This research confronts the following concrete properties: water absorptions (by immersion and capillarity), electrical resistivity and compressive strength. Concrete mixtures with two types of cement were tested. Results showed that concretes with higher content of pozzolan had higher resistivity and greater absorption by capillarity, for water/cement ratios lower than 0,60. This behavior is attributed to reduced pore diameters and microstructure densification. However, for water/cement ratio of 0,60, concrete with lower content of pozzolan presented higher absorption by capillarity. It was observed that the compressive strength and the electrical resistivity behaved inversely proportional to the water/cement ratio, and the absorption by immersion and capillarity are directly proportional to the water/cement ratio. Correlations with high determination coefficients were found between tests.

Physic nut is a plant widely cultivated in various regions of tropical America, Asia and Africa that adapts well to arid and degraded soils. This essay aimed to evaluate the effect of arbuscular mycorrhizal fungi (AMF) on solarized substrate for production of seedlings with seeds from states of Pernambuco, Minas Gerais and Mato Grosso do Sul, Brazil. AMF used included a mixture of Clarum glomus, Gigaspora margarita, Scutellospora hterogama and Gigaspora calospora. Treatments consisted of inoculation in that mixture with solarized substrate, non-solarized and control (without inoculation). The results showed that seedlings produced with seeds from Pernambuco had the lowest values for leaf number and the ratio between height and diameter, while those formed with seeds from Mato Grosso do Sul revealed the largest height and diameter. Inoculation with AMF in solarized oxisol red (LV) substrate did not alter morphology of physic nut seedlings produced from seeds of the three provenances tested.

ABSTRACT This study aimed to identify wavelengths based on leaf reflectance (400-1050 nm) to estimate white mold severity in common beans at different seasons. Two experiments were carried out, one during fall and another in winter. Partial Least Squares (PLS) regression was used to establish a set of wavelengths that better estimates the disease severity at a specific date. Therefore, observations were previously divided in two sub-groups. The first one (calibration) was used for model building and the second subgroup for model testing. Error measurements and correlation between measured and predicted values of disease severity index were employed to provide the best wavelengths in both seasons. The average indexes of each experiment were of 5.8% and 7.4%, which is considered low. Spectral bands ranged between blue and green, green and red, and red and infrared, being most sensitive for disease estimation. Beyond the transition ranges, other spectral regions also presented wavelengths with potential to determine the disease severity, such as red, green, and near infrared.

The paper presents the results of an analysis of a two-stage pilot plant for the removal of toluene and benzene from the exhaust air of an industrial wastewater treatment plant (WWTP). The two-stage air process combines a water scrubber and a biotrickling filter (BTF) in sequence, and treats air stripped from the liquid phase compartments of the WWTP. During the experimental period, the pilot plant treated an airflow of 600 Nm3h-1. Average concentrations of the waste air stream entering the water scrubber were 10.61 mg Nm-3 benzene and 9.26 mg Nm-3 toluene. The water scrubber obtained medium-high removal efficiencies (averages 51% and 60%, for benzene and toluene, respectively). Subsequent passage through the BTF allowed a further reduction of average concentrations, which decreased to 2.10 mg Nm-3 benzene and to 0.84 mg Nm-3 toluene, thereby allowing overall average removal efficiencies (REs) of 80% and 91% for benzene and toluene, respectively. Results prove the benefits obtained from a combination of different removal technologies: water scrubbers to remove peak concentrations and soluble compounds, and BTFs to remove compounds with lower solubility, due to the biodegradation performed by microorganisms.

Nicolas Théodore de Saussure (1767-1845) is well recognized for his pioneering work about plant physiology and the interaction between plants, soil, and atmosphere. Here we describe some of his findings in chemistry and physical chemistry, in particular the possible combination of alumina with carbon dioxide to generate aluminum carbonate and its different degrees of desiccation in its various states. He demonstrated that starch mixed with water alone was able to generate crystallizable sugar in larger amount than when acted on by sulfuric acid; his procedure yielded also amidine, a substance with properties intermediate between starch and gum. Saussure used a eudiometric procedure to determine the correct composition of ethanol, diethyl ether, and ethylene. He carried an extensive study of the absorption of pure gases and their mixtures by many solids and liquids and proved that all porous bodies were capable of absorbing gases and that this property depended on factors such as the number of pores and their dimension, the affinity between the gas and the solid body, and the compressibility of the gas. In the case of mixtures, two gases absorbed in charcoal often experienced a greater condensation than each would in a separate state. The absorption of a gas by a liquid was little affected by its viscosity, although it affected the time required for achieving saturation. His electrical experiments showed that hydrogen appeared to combine with part of the oxygen of carbon dioxide to form water, while the dioxide was reduced to he monoxide.

Se estudia un problema de difusión no local con término de absorción y condiciones de frontera de Neumann. Se analiza la existencia y unicidad de las soluciones, y se da un principio de comparación para ellas. Se analiza la extinción de la solución para algunos términos de absorción. Abstract. We study a nonlocal diffusion problem with absorption term and Neumann boundary conditions. We prove the existence and uniqueness of solutions, and give a comparison principle for them. The quenching phenomena of solutions is analyzed for some absorption term.

En el trabajo se presenta la evaluación económica de la implementación de la climatización con empleo de la energía solar para las condiciones de radiación y temperatura ambiente en La Habana, Cuba. La evaluación se realizó para máquinas de pequeña capacidad (7-35 kW) las cuales se encuentran en el mercado internacional. El estudio se realizó empleando el tiempo de recuperación de la inversión y el ahorro en el ciclo de vida como criterios de medida. Además se analizó la influencia que tiene la relación volumen de almacenamiento/área de captación (V/A) sobre la fracción solar, la energía auxiliar, el costo de la energía ahorrada, ahorro de la energía primaria y ahorro en la cantidad de CO2 emitido. Se empleó el método P1-P2 para los cálculos económicos así como el método Φ-fchart para la obtención de la fracción solar. El precio del petróleo se varió entre los 100 y 200 $/barril. This work presents an economical evaluation of implementing a solar air-conditioning system using solar energy in Havana, Cuba. It was studied the feasibility of systems of small and medium capacities (7-35 kW) of absorption refrigeration machines which be in the world market. The parameters that were taken for the feasibility were the payback time and life cycle savings. Also it was analyzed the influence of the ratio storage volume/solar collector area (V/A) on solar fraction, auxiliary energy, saved energy cost, saved primary energy and emitted CO2. Besides, it was used the P1-P2 method for the economical aspects and the Φ-fchart method in order to determine de solar fraction. The price of petroleum was varied from 100 to 200$/barrel.

I analyze the concepts of theatre and film in Michael Fried's "Art and Objecthood" (1967), in order to argue for a cinematic theatricality immune to the anti-theatrical prejudice often found in works about the intersection of these two art forms. Given the tangential place of movies in Fried's article, other texts are used (mostly from the same period and mainly from the Cahiers du Cinéma tradition) to deconstruct Fried's idea of film so that a new concept can emerge. Two scenes, one from Godard and the other from Tsai Ming-liang, are used to illustrate the proposed theatricality.

O objetivo desse estudo foi investigar o emprego dos componentes da eficiência no uso de nitrogênio e das atividades das enzimas nitrato redutase e glutamina sintetase na seleção de genótipos de milho eficientes no uso de nitrogênio (N). Foram avaliados 10 genótipos de milho em estádio de V4 em condições de alto e baixo N. O experimento foi composto por um fatorial 2 x 10 (dois níveis de N e 10 genótipos de milho) em delineamento inteiramente casualizados com três repetições. Os seguintes caracteres foram avaliados: as eficiências na absorção (EAbN), na utilização (EUtN) e no uso de N (EUsN) e as atividades das enzimas glutamina sintetase (GS) e nitrato redutase (NR). Para os caracteres que o efeito de genótipos foi significativo (pThe aim of this study was to investigate the employment of components of the nitrogen efficiency use (NUE), and of the activities of the nitrate reductase and glutamine synthetase enzymes in the selection of nitrogen use efficient maize genotypes of maize. Ten maize genotypes at V4 stage were evaluated under high and low N. The experiment consisted of a 2 x 10 factorial (two levels of N and ten maize genotypes), in a randomized complete block design with three replicates. The following traits were evaluated: N uptake efficiency (NUpE), N utilization efficiency (NUtE) and N use efficiency (NUE), and activities of the glutamine synthetase (GS) and nitrate reductase (NR) enzymes. For traits which the effect of genotype was significant (p

Objective. Evaluate the effect of increasing P intake on nutrient digestibility, and compare the true and apparent absorption coefficients of P and Ca in lambs. Materials and methods. Twenty-four Santa Ines sheep, with an average weight of 33.6 ± 1.6 kg, were distributed into four treatments (0, 2, 4 and 6 g/day of supplementary P) with forage: concentrate ratio of 70:30. The study of apparent nutrient digestibility was conducted during the first week, using the total feces collection method. During the second week, after injection of 7.4 MBq of 32P and 7.7 MBq of 45Ca, apparent (AAC) and true (TAC) absorption coefficients of P and Ca were determined. The lambs were kept in metabolic cages. Results. The increase in P intake did not affect (p>0.05) dry matter, crude protein, NDF or ADF digestibility, but the TAC of P and Ca and mineral matter digestibility decreased. The AAC was not affected (p=0.10). A cubic relationship was observed between P intake and TAC (TAC=2.16–1.95X+0.55X2-0.04X3; R2=0.38) and linear relationship with the TAC of Ca (TAC=0.559–0.03X; R2=0.26). TAC and AAC values were different (p

The basic function of the gallbladder in humans is one of protection. The accumulation of the primary bile acids (cholic acid and chenodeoxycholic acid) in the gallbladder reduces the formation of the secondary bile acids (deoxycholic acid and lithocholic acid), thus diminishing their concentration in the so-called gallbladder-independent enterohepatic circulation and protecting the liver, the stomach mucosa, the gallbladder, and the colon from their toxic hydrophobic effects. The presence or absence of the gallbladder in mammals is a determining factor in the synthesis of hydrophobic or hydrophilic bile acids. Because the gallbladder contracts 5-20 min after food is in the stomach and the “gastric chyme” moves from the stomach to the duodenum 1-3 h later, the function of the gallbladder bile in digestion may be insignificant. The aim of this article was to provide a detailed review of the role of the gallbladder and the mechanisms related to bile formation in humans.

Light multi-layered facade systems in general have been acoustically little studied. The data available suggests they do not usually fulfil the sound insulation values required in the Technical Building Code (CTE) in particularly in noisy environments. Therefore the main objectives of this study, is to obtain light multi-layered façade systems with a high degree of acoustic insulation that can be used in noisy environments. While in turn showing excellent thermal characteristics, without neglecting important aspects such as the sustainability of materials, industrialization, costs, among others. This article will explain the process that has been followed to carry out an investigation on the acoustic behaviour of light multi-layered facades. For this purpose acoustic behaviour and sound intensimetry measurement methods have been used. After obtaining these results, a comparison between light multi-layered and traditional facades was made.

El presente trabajo estudia el comportamiento electromagnético de un dispositivo absorbedor con estructura metamaterial quiral. El dispositivo propuesto consiste en una estructura de planos paralelos, con rosetas metálicas implantadas, físicamente separadas por capas dieléctricas. Para demostrar el efecto absorbedor de tal estructura, se ejecuta una simulación básica, en la cual se hace incidir un haz gaussiano sobre el metamaterial quiral. Los resultados muestran que, para efectos prácticos, ocurre absorción total. Este comportamiento hace que la estructura propuesta se comporte como un "agujero negro espacial".The electromagnetic behavior of an absorber device with chiral metamaterial structure is studied. The proposed device is a structure formed by parallel planes with implanted metallic rosettes, physically separated by dielectric layers. In order to show the absorbing properties of such structure, a basic simulation is run, in which a gaussian beam is fed incident to the chiral metamaterial. Results show that there is, for practical purposes, full absorption. This behavior makes the proposed structure behave as a "spatial black hole".

Inúmeros fatores podem influenciar a absorção da levotiroxina nos pacientes hipotireoideos, especialmente medicações e administração concomitante com alimentos. Nos pacientes internados em unidade de terapia intensiva, estes fatores são mais evidentes, principalmente em função da dieta enteral contínua além de diversas medicações que podem interferir na sua absorção. Alterações adaptativas no eixo hipotálamo-hipófise-tireóide e alterações clínicas comumente presentes em pacientes críticos que podem ter contribuição de um hipotiroidismo não tratado se associam tornando ainda mais difícil o manuseio da reposição de levotiroxina. Relatamos dois casos de pacientes com hipotiroidismo internados em unidade de terapia intensiva, com suas respectivas abordagens para reposição de levotiroxina, levantando questões controversas como: qual a dose ideal de reposição, velocidade no incremento das doses, necessidade de associação com triiodotironina, interferência da dieta enteral na absorção, e finalmente as possíveis conseqüências de um hipotiroidismo não tratado e as formas clínicas e laboratoriais para monitorizar as doses hormonais administradas.Levothyroxine absorption in hypothyroid patients can be influenced by several factors, particularly medications and concomitant food administration. This is especially evident in intensive care unit patients, where a continual enteral diet and the administration of multiple medications changes its absorption. Changes or adaptations in the hypothalamic-pituitary-thyroid axis, in conjunction with clinical abnormalities possibly related to under-treatment of hypothyroidism, render levothyroxine replacement therapy very challenging. Here, we report two intensive care hypothyroidism patients and their respective levothyroxine replacement management issues, focusing on a number of controversial issues, such as the optimal replacement dose, how fast the levothyroxine doses should be increased, triiodothyronine requirements, the interference of an enteral diet with absorption, and finally, the possible consequences of undertreated hypothyroidism and levothyroxine replacement monitoring useful clinical/laboratory parameters.

Com o objetivo de avaliar marcha de absorção de macro e micronutrientes na couve-flor cultivada em substrato, um experimento foi conduzido em casa de vegetação da UNESP, Campus de Jaboticabal, SP. O delineamento experimental foi de blocos ao acaso, com seis tratamentos e cinco repetições. Os tratamentos foram constituídos pelas épocas de amostragem (20; 30; 40; 50; 60 e 70 dias após o transplante). Avaliaram-se os teores e acúmulo dos macro e micronutrientes da parte aérea e raiz. A maior demanda de nutriente aconteceu no período de 60 a 70 (DAT) para macro e micronutrientes. A ordem decrescente dos macronutrientes acumulados pela couve-flor foi: K, N, S, P, Mg e Ca e os micro foi: Fe, Zn, B, Mn e Cu.With the objective of evaluating the progress of absorption of macro and micronutrients in cauliflower cultivated in substrate, an experiment was conducted in a greenhouse at the Universidade do Estado de São Paulo, in Jaboticabal, Brazil. The experimental desing used was randomized blocks, with six treatments and five replicates. The treatments comprised times of sampling (20; 30; 40; 50; 60 and 70 days after the transplant). The composition and accumulation of the macro and micronutrients of the shoot and root were evaluated. The biggest demand of nutrient happened in the period of 60 to 70 (DAT) for macro and micronutrients. The decreasing order of the macronutrients accumulated by the cauliflower was K, N, S, P, Mg and Ca and for micronutrients Fe, Zn, B, Mn and Cu.

Para los casos eventuales de falta de información experimental, se presenta una alternativa para poder disponer de datos confiables y validables de los coeficientes de absorción por ozono y de dispersión por aire puro de la radiación solar ultravioleta B (radiación UV-B); dichos coeficientes son requeridos para la estimación de la columna total de ozono al aplicar la espectrofotometría Dobson. La alternativa propuesta tiene que ver con el uso cuidadoso de interpolación, aplicada a series de datos, debidamente validados. Se plantea un ensayo de validación indirecta aplicando la metodología Dobson a la información obtenida de esta manera y así determinar el ozono total.For eventual cases of lack of experimental data, an alternative in order to have reliable and verifiable results for both ozone absorption and pure air dispersion coefficients of solar ultraviolet B radiation (UV-B) is shown; these coefficients are required to estimate ozone total column in Dobson spectrophotometry. The proposed alternative has to do with the careful use of interpolation applied to sets of properly validated data. We present an indirect validation test using Dobson methodology to the information obtained in this manner and thus determine the total ozone.

Work engagement is described by dedication, vigor, and absorption. The most widely used measure of engagement is the Utrecht Work Engagement Scale (UWES), intended to measure engagement for any occupational group. This research aims to study psychometric properties of the UWES for its use in the Dominican Republic and other Caribbean Spanish-speaking countries. The Composite Reliability Index (CRI) as well as alphas were calculated, indicating good internal consistency. Confirmatory factor analyses were carried out to test its dimensionality. Both tested models showed extremely good fit to the data, which called for model comparison. The three-factor solution was retained as the one showing the best relative fit. However, the three dimensions of the scale were largely correlated, providing evidence for some overlapping. Regarding criterion-related validity, the three factors were correlated as expected with the three dimensions of burnout, working climate, and working conditions.

Los acondicionadores de aire por absorción se han comercializado en Venezuela en pequeña escala por más de treinta años. Existe un renovado interés por su uso como alternativa para la reducción en el consumo de electricidad residencial y desde el punto de vista ecológico por su bajo impacto ambiental. A pesar de que estos sistemas han sido estudiados ampliamente, aún los datos experimentales son escasos. El presente trabajo busca sentar las bases para un estudio a largo plazo que permita fundamentar el uso masivo de esta tecnología a nivel nacional. El artículo describe los equipos e instrumentos necesarios para el ensamblaje de un banco de pruebas y se emplea una metodología para evaluar las máquinas comerciales sin desarmarlas. Se realizaron comparaciones entre las mediciones efectuadas, datos suministrados por el fabricante y la literatura con el propósito de verificar un nivel de funcionamiento apropiado pudiéndose establecer una serie de conclusiones en cuanto a parámetros operativos basados en tal comparación. Entre otras cosas, se estableció el impacto de la fluctuación del gas combustible en la operación de la máquina y la factibilidad de su operación intermitente.Absorption air conditioners have been trade in Venezuela in small scale for over 30 years. Currently it became an attractive alternative for the reduction in electricity consumption in residential areas and from an ecological point of view for its low environmental impact. Although these systems have been widely studied, there is few experimental data. The present work is aimed to base a long term study that propose massive use of this technology in the country. The article describes equipment and instruments required for the assembly of a benchtest and a methodology is followed to evaluate commercial air conditioners without dismantling them. Comparison were undertaken between the measurements performed, data supplied by the manufacturer and the literature with the purpose of verifying an appropriate operation. A series of conclusions have been withdrawn about operative parameters, among others, it has been established the effect of combustible gas fluctuation in the machine perfomance and feasibility of non-continuous operation.

Este trabalho foi desenvolvido com o objetivo de avaliar a eficácia e o pH de caldas de glifosato após a adição de fertilizantes nitrogenados e utilização de pulverizador pressurizado por CO2. Em campo, foram aplicadas duas doses de glifosato (360 e 720 g ha-1), isoladas ou combinadas a duas concentrações de ureia (2,5 e 5,0 g L-1) ou sulfato de amônio (7,5 e 15,0 g L-1). Em laboratório, mensurou-se o pH de caldas de glifosato após o uso de diferentes concentrações do produto e dos fertilizantes nitrogenados e após a utilização do pulverizador pressurizado por CO2. Em todas as avaliações do experimento em campo, a menor dose de glifosato teve maior eficácia biológica após a adição de sulfato de amônio (15 g L-1) à calda. A ureia (5 g L-1) proporcionou efeitos benéficos somente na avaliação aos 28 dias após a aplicação. Em laboratório, o aumento da concentração de glifosato promoveu gradativa acidificação da calda de pulverização, com estabilização do pH da solução em 4,5. O sulfato de amônio causou pequena acidificação da calda herbicida, enquanto a ureia não alterou o pH. O uso do pulverizador pressurizado por CO2 pouco alterou o pH da calda de glifosato. A maior eficácia do glifosato após a adição de fertilizantes nitrogenados à calda está pouco relacionada com alterações no pH da solução.This work was developed with the objective of evaluating the efficacy and the pH of glyphosate spray solutions after the addition of nitrogen fertilizers and the use of CO2-pressurized sprayer. In field conditions, two rates of glyphosate (360 and 720 g ha-1) were applied either alone or combined with two concentrations of urea (2.5 and 5.0 g L-1) or ammonium sulfate (7.5 and 15.0 g L-1). In laboratory, the pH of the glyphosate solutions was measured after using different concentrations of the product and nitrogen fertilizers and after using a CO2-pressurized sprayer. For all field condition evaluations, the lowest glyphosate rate had higher biological efficacy after the addition of ammonium sulfate (15 g L-1) to the spray solution. Urea (5 g L-1) promoted benefits only at the 28th-day evaluation. In laboratory, the increase of glyphosate concentration promoted gradual acidification of the spray solution, which stabilized at pH 4.5. Ammonium sulfate caused minor acidification of the herbicide solution, whereas urea did not change the pH. The use of CO2-pressurized sprayer had small effect on the solution's pH. Highest glyphosate efficacy identified after the addition of nitrogen fertilizers has little relation with changes on the solution's pH.

O cálcio é um nutriente essencial necessário em diversas funções biológicas. Estudos têm demonstrado a associação entre o baixo consumo de cálcio e doenças crônicas, entre elas osteoporose, câncer de colón, hipertensão arterial e obesidade. Entretanto, grande parte da população brasileira apresenta consumo de cálcio abaixo do recomendado. Este artigo objetiva revisar os fatores endógenos (idade e estado hormonal) e exógenos (fitatos, oxalatos, sódio, compostos bioativos e vitamina D) que influenciam a absorção do cálcio, bem como as principais metodologias utilizadas para avaliar a absorção e biodisponibilidade desse nutriente. Discorre-se sobre os possíveis fatores para o baixo consumo de cálcio: 1) Hábito alimentar - substituição de leite por bebidas com baixo teor de cálcio como o refrigerante, refeições realizadas fora de casa e a não realização de refeições como o café da manhã; 2) Alto custo dos alimentos fontes de cálcio. Além disso, este artigo discute as estratégias para otimizar o consumo do cálcio, que incluem: 1) Aumentar o conhecimento sobre a importância do consumo de cálcio para a saúde e as principais fontes alimentares desse nutriente; 2) Aumentar a disponibilidade de alimentos fortificados com cálcio; 3) Uso de suplementos em grupos específicos - quando e como administrar os sais de cálcio.Calcium is an essential nutrient required for numerous biological functions. Studies have demonstrated an association between low calcium intake and chronic diseases, such as osteoporosis, colon cancer, hypertension, and obesity. However, most Brazilians do not meet the adequate intake for calcium. This review focuses on the endogenous (age, hormonal state) and exogenous (phytate, oxalate, sodium, bioactive compounds and vitamin D) factors that can influence calcium absorption. The main methods used for evaluating calcium absorption and bioavailability. The potential factors for the low calcium intake: 1) Food habits - substitution of milk for soft drinks, eating away from home and skipping meals specially breakfast; 2) High cost of dairy food. Besides, this article discuss strategies to optimize calcium intake: 1) Increase knowledge of the relationship between calcium and health and the main food sources; 2) Increase availability of calcium-fortified foods; 3) Supplement use for target groups - when and how administrate calcium salts.

The article discusses the effect of the assumptions about moisture content on the design of ventilated façades with porous natural stone cladding. Moisture is shown to impact cladding strength and condition its dimensions. For this reason the performance of such façades when exposed to water should be analyzed more fully than specified in EN standards. An example is given of how to conduct such an analysis, along with guidelines for choosing a moisture content value that correctly reflects the absorption levels attainable in such façades. This value is then used to determine panel mechanical strength. Application of the method to three sandstones from Northeastern Spain showed the utility of the type of analysis proposed.

Avaliou-se a biodisponibilidade de ferro de diferentes compostos visando sua utilização em dietas para leitões desmamados. Utilizaram-se 44 leitões (7 não-anêmicos e 37 anêmicos) desmamados aos 21 dias de idade (7,3 ± 1,8 kg) e distribuídos em dois grupos: grupo não-anêmico e grupo anêmico. Durante sete dias, os animais do grupo não-anêmico receberam dieta com FeSO4.7H2O (sulfato ferroso hepta-hidratado) na dose de 100 mg/kg e os do grupo anêmico, dieta sem ferro (Iron bioavailability from different compounds was evaluated to be used in diets for weaned piglets. Forty four piglets (7 non-anemic and 37 anemic) weaned at 21 days old (7.3 ± 1.8 kg) were distributed into two groups: non-anemic group and anemic group. During seven days, the animals from non-anemic group were fed diet with ferrous sulfate hepthydrate (FeSO4.7H2O) in the dose of 100 mg/kg and of the anemic group, diet without iron (

Individuos que dicen ver el aura/energía en forma espontánea también tienden a tener un nivel más elevado de actividad imaginativa/fantaseosa o de propensidad a la fantasía. Hay indicadores que muestran que quienes experimentan alta capacidad de absorción, usualmente experimentan también diversas formas parasomáticas, alucinaciones táctiles, y sensaciones de energías sutiles, asi como también ideación esquizotípica, error perceptual, y mayor sinestesia. El objetivo es correlacionar puntajes de absorción psicológica, disociación, propensidad a la fantasía, intensidad de la imaginería, y tendencia a la esquizotipia en individuos que dicen ver el aura (N=83) en comparación con un grupo sin experiencias (N=503). La muestra incluyó 678 estudiantes de psicología de ambos sexos, 449 (76,5%) mujeres y 139 (23,5%) varones, cuya rango etario es de 17 y 57 años (Media=25,54; SD=7,22) residentes en la Ciudad de Buenos Aires y alrededores. Ningun estudiante recibió compensación económica. Respecto a la experiencia de ver el aura, se formuló la pregunta de la siguiente manera: "¿Ha tenido alguna experiencia usted es capaz de ver campos de energia o luces alrededor del cuerpo de una persona? (si duda, por favor, responda no)". Si la respuesta es afirmativa, la pregunta también mapea tres dimensiones de la experiencia: frecuencia de la experiencia, explicación subjetiva (racional, desconocida y paranormal) de la experiencia, y positivo o negativo impacto (emocional) en una escala Likert, siendo 1 positivo y 7 negativo. Los resultados muestran mayor nivel de esquizotipia cognitivo perceptual en comparación con quienes no tienen la experiencia. Posiblemente, estas personas tienen mucha más intensa vida imaginativa. Esta experiencia no necesariamente posee un significado psicopatológico para el individuo; quienes ven el aura simplemente podrían ser sensibles a las experiencias perceptuales anómalas.Individuals who claim being able to spontaneously see the "aura" or energy field of a person, also tend to exhibit elevated levels of imaginative processing or fantasy proneness. There are some indications that those who have a high capacity for absorption usually also experience different parasomatic shapes, tactile hallucinations and sensations of subtle energies, as well as schizotypical ideation, perceptual error and increased synesthesia. The objective is to calculate the correlations of psychological absorption scores, dissociation, fantasy proneness, intensity of imagination and the schizotypical tendency of people who claim to see auras (N=83), in comparison to a group of people lacking these experiences (N=503). The results indicate a higher level of cognitive perceptual schizotypy than for those who do not have this experience. Possibly, these people have a much more intense imaginative life. This does not necessarily have any psychopathological implications for the individual; people who see auras might simply be sensitive to anomalous perceptual experiences.

The absorption and bioavailability of the minerals Ca, Fe and Zn in balanced and mineral restricted diets with the addition of the food supplement multi-mixture (MM), was evaluated. A biological assay was carried out for 28 days with recently weaned Wistar rats, using 3 treatments and 8 animals in each group. The diets offered to each group were distributed as follows: CD – Control Diet (AIN-93G); CcD/MM – Control Diet + Supplement 5% MM; DRMIXc/MM – Control Diet with Mineral Restricted + Supplement 5% MM). The animals were monitored for weight; amount of diet consumed and amount of faeces excreted. They were sacrifi ced at the end of the experimental period and the pair of femurs, pancreas and liver removed for the determination of Ca, Fe and Zn. The CcD/MM diet presented absorption of Ca and Fe and bioavailability of Ca, Fe and Zn equal to that of CD, showing no statistical difference between the treatments. However the DRMIXcD/MM diet presented an increase in Ca absorption, equal absorption of Fe and an increase in the bioavailability of Ca, Fe and Zn when compared to CD. It was concluded that when fed on a balanced diet supplemented with 5% MM, there was no increase in the bioavailability of Ca, Fe or Zn, whereas when fed on a mineral defi cient diet, the group of animals that received supplementation with 5% MM, presented greater absorption and bioavailability of these minerals.

Los ácidos grasos de cadena media (AGCM) contienen entre 6 y 12 átomos de carbono y son digeridos, absorbidos y metabolizados de manera distinta que los ácidos grasos de cadena larga (AGCL). En este trabajo se revisan algunas de las utilidades potenciales y reales de los AGCM y su papel en la salud. Por ello, se utilizan en nutrición enteral y parenteral debido a la buena absorción que presentan; y en fórmulas lácteas en niños prematuros para mejorar la absorción de calcio. AGMC han cobrado un gran interés especialmente por su posible papel en el tratamiento y prevención de la obesidad. Al ser más hidrosolubles, no se incorporan a los quilomicrones y se acepta que no participan directamente en la lipogénesis. Son capaces de incrementar el efecto termogénico de los alimentos y en su metabolización elevan la formación de cuerpos cetónicos con el consiguiente efecto anorexígeno. No obstante, se requiere ingerir cantidades elevadas de AGCM para obtener efectos significativos en la reducción de peso. Los efectos sobre el metabolismo lipoproteico son controvertidos. Así, aunque parecen disminuir la respuesta trigliceridémica postprandial, los resultados no son uniformes respecto a sus efectos sobre la trigliceridemia y colesterolemia. A pesar de ello, se diseñan cada vez más productos en los que se incorporan grasas con AGCM para el tratamiento de la obesidad y sobrepeso, habiendo sido considerados por la ADA como componentes "GRAS" (Generally Recommended As Safe). Son necesarios estudios a más largo plazo para garantizar la utilidad del consumo de estos compuestos, particularmente en el tratamiento y prevención de obesidad.Middle-chain fatty acids (MCFA) contain 6-12 carbon atoms and are digested, absorbed and metabolized differently than long-chain fatty acids (LCFA). This work reviews some of the potential and real utilities of MCFA and their role on health. For this reason, they are used in enteral and parenteral nutrition because of their good absorption, and in premature-feeding milk-based formulas in order to improve calcium absorption. MCFA have become particularly important because of their possible role in treating and preventing obesity. Since they are more water soluble, they are taken-up by chylomicrons, and it is believed that they do not directly participate in lipogenesis. They are able to increase the thermogenic effect of foods, and its metabolism increases the production of ketonic agents with the subsequent anorexigenic effect. However, high doses of MCFA are required to obtain significant effects on weight reduction. The effects on lipid-protein metabolism are controversial. So, although they seem to reduce the post-prandial triglyceridemic response, the results their effects are not uniform regarding triglyceridemia and cholesterolemia. In spite of this, more and more products are being designed incorporating MCFA to treat obesity and overweight, having been considered as "GRAS" (Generally Recommended as Safe") components by the ADA. Further long-term studies are needed to warrant the usefulness of consumption of these compounds, particularly in the treatment and prevention of obesity.

Introducción: Dentro de los apósitos destinados a la cura en ambiente húmedo, las espumas constituyen un tipo de apósito especialmente indicado para el tratamiento de heridas altamente exudativas debido a su gran capacidad de absorción. Son apósitos atraumáticos que protegen la zona perilesional y mantienen el lecho húmedo favoreciendo la epitelización y aliviando el dolor, por lo que ocupan un espacio muy específico en el cuidado de las úlceras vasculares y por presión. Material y método: Estudio experimental in vitro para evaluar las características de 6 tipos de apósitos de espuma polimérica: SKINFOAM no adhesivo (SF1) y adhesivo (SF2), ALLEVYN no adhesivo (A1) y adhesivo (A2) y BIATAIN no adhesivo (B1) y adhesivo (B2). Las características valoradas fueron: capacidad de absorción y control de exudados, caracterización de la superficie en contacto, capacidad de transpiración, conformabilidad y protección antimicrobiana. Resultados: Las pruebas de absorción y control de exudados muestran cómo los apósitos SF1 y SF2 obtienen la mayor absorción por unidad de peso mientras que los modelos B1 y B2 se deforman de manera evidente; incluso en el caso del apósito adhesivo B2 la almohadilla de foam se despegó del film adhesivo. El experimento por goteo no pudo realizarse con los apósitos A1 y A2 por no retener las gotas de solución, ya que la capa adherente de contacto interna evita la retención. Las medidas de rugosidad mostraron la excelente suavidad de los apósitos SF1 y SF2, comportamiento que influirá directamente sobre el síntoma del dolor. Las tasas de transpiración de vapor de agua, más altas, particularmente para los modelos adhesivos, fueron para los apósitos SF2 y B1. El apósito más fácilmente extensible fue el SF1 y la protección bacteriana fue similar en todos los apósitos. Conclusiones: Los resultados muestran que los apósitos SF1 entre los no adhesivos y SF2 entre los adhesivos (modelos SKINFOAM) son los que mejor comportamiento global tienen de las propiedades estudiadas. Respecto a los otros modelos, cabe destacar la capacidad de absorción por unidad de superficie de los modelos A1 y B2, la retención de exudados bajo presión y la mínima cantidad de agua libre del modelo B1 y los resultados en la prueba de transpiración del modelo A2.Introduction: Of the dressings used for healing in wet environments, foam is a type of dressing that is particularly indicated for the treatment of highly exudative wounds due to its great absorption capacity. They are atraumatic dressings that protect the perilesional area and keep the bed moist promoting epithelialization and providing pain relief, thus occupying a very specific space in the care of vascular and pressure ulcers. Material and method: In vitro experimental study to evaluate the characteristics of 6 types of polymeric foam dressings: Non-adhesive (SF1) and adhesive (SF2) SKINFOAM, non-adhesive (A1) and adhesive (A2) ALLEVYN and non-adhesive (B1) and adhesive (B2) BIATAIN. The characteristics assessed were: exudate absorption and control capacity, characterisation of the contact surface, transpiration, conformability and antimicrobial protection capacity. Results: The exudate absorption and control tests show how dressings SF1 and SF2 obtain greater absorption per unit of weight while models B1 and B2 are evidently deformed, and even in the case of the adhesive B2 dressing, the foam padding detached from the adhesive film. The drip experiment could not be carried out with dressings A1 and A2 as the drops of solution could not be retained since the internal contact adherence layer prevents retention. The roughness measurements demonstrated the excellent softness of the SF1 and SF2 dressings, a behaviour that will have a direct impact on pain symptoms. The highest water vapour transpiration rates, particularly for adhesive models, were for dressings SF2 and B1. The easiest-to-extend dressing was the SF1, and bacterial protection was similar in all the dressings. The dressings with the greatest absorption capacity were model B1 by unit of surface and model A1 by unit of weight. The maximum exudate retention under pressure was that of dressing C1 among the non-adhesives (96.79%) and A2 among the adhesives (97.13%). Dressings C1 and C2 presented the lowest amount of free water. The highest rates of water vapour transpiration corresponded to dressings C1 and A2, respectively. Dressing A1 presented the best surface characteristics. All the models had a similar behaviour in all the microbiological tests. Conclusions: The results show that the SF1 dressings from among the non-adhesives and the SF2 from among the adhesives (Skinfoam models) present the best overall behaviour in terms of the properties studied. Regarding the other models, mention must be made of the absorption capacity per unit of surface of models A1 and B2, the retention of exudates under pressure and the minimum amount of free water of model B1 and the results of model A2 in the transpiration test.

The present study aimed: to characterize the physical, chemical and mechanical properties of recycled aggregate from construction and concrete structure demolition waste, processed before and after crushing; to characterize fresh and hardened concrete made with such recycled aggregate; and to design different doses varying the water/cement ratio, the amount of cement and the use of superplasticizing admixtures to offset the effects of absorption. The ultimate objective was to provide a broader perspective of the use of recycled aggregate in the manufacture of new concrete.

Concrete instability may lead to the non-uniform distribution of its properties. The homogeneity of self-consolidating concrete in vertically cast members was therefore explored in this study, analyzing both resistance to segregation and pore structure uniformity. To this end, two series of concretes were prepared, self-consolidating and traditional vibrated materials, with different w/c ratios and types of cement. The results showed that selfconsolidating concretes exhibit high resistance to segregation, albeit slightly lower than found in the traditional mixtures. The pore structure in the former, however, tended to be slightly more uniform, probably as a result of less intense bleeding. Such concretes are also characterized by greater bulk density, lower porosity and smaller mean pore size, which translates into a higher resistance to pressurized water. For pore diameters of over about 0.5 μm, however, the pore size distribution was found to be similar to the distribution in traditional concretes, with similar absorption rates.

Resumen Se sintetizaron hidrogeles de acrilamida (AAm)/ácido maleico (AM), ácido acrílico (AAc)/ácido maleico (AM) y ácido acrílico (AAc)/octiléster del ácido 2-metilenbutanodioico (MI-8) en presencia de persulfato de amonio como iniciador y N,N’-metilenbisacrilamida como agente entrecruzante. El grado de hinchamiento de los hidrogeles fue caracterizado en ensayos de absorción a dos temperaturas: 25 y 37°C. Se estudió también su hinchamiento en soluciones de sales de cationes divalentes, como el cobre mediante la técnica de espectroscopia de emisión de plasma. Durante el estudio de hinchamiento, se encontró que los hidrogeles sintetizados presentaron isotermas que se extienden asintóticamente hacia el equilibrio. Se comprobó que un aumento en el contenido de ácido maleico influye directamente en las propiedades de hinchamiento (un incremento del 30% en AM aumenta el contenido de agua del hidrogel en el equilibrio en un 12%). Respecto a la captación de cationes cobre, se encontró que la concentración disminuyó en la solución inicial, después de haber estado en contacto con los hidrogeles. Además, se midieron variaciones de pH en las soluciones que permitieron clarificar el mecanismo de reacción entre los hidrogeles y los iones metálicosAbstract Acrylamide (AAm)/maleic acid (AM), acrylic acid (AAc)/maleic acid (AM) and acrylic acid (AAc)/2 - methylenebutanedioic acid octylesther (MI-8) hydrogels were sinthetysed in presence of amonium persulfate as initiator and N,N’-methylenebisacrylamide as crosslinking agent. The grade of hydrogels swelling was determined by two test at diferent temperatures: 25 and 37°C. The hydrogels swelling also was studied in divalents cations salts solutions, like copper by way of plasma spectroscopy emition. The swelling of synthesised hydrogels test shows isothermal that extends asinthotically to the equilibrium. It was demonstrated that the maleic acid content had a direct influence in the swelling properties (an increment of 30% in AM rise the content of water in the hydrogel in 12%). Respect to the copper cations adsorption, we found that the concentration decrease in the initial solution after to be in contact with the hydrogels. Moreover, pH variation was measured allowing understand the reaction mechanism between the hydrogels and metallic ions

En el trabajo se presenta la evaluación económica de la implementación de la climatización con empleo de la energía solar para las condiciones de radiación y temperatura ambiente en La Habana, Cuba. La evaluación se realizó para máquinas de pequeña capacidad (7-35 kW) las cuales se encuentran en el mercado internacional. El estudio se realizó empleando el tiempo de recuperación de la inversión y el ahorro en el ciclo de vida como criterios de medida. Además se analizó la influencia que tiene la relación volumen de almacenamiento/área de captación (V/A) sobre la fracción solar, la energía auxiliar, el costo de la energía ahorrada, ahorro de la energía primaria y ahorro en la cantidad de CO2 emitido. Se empleó el método P1-P2 para los cálculos económicos así como el método Φ-fchart para la obtención de la fracción solar. El precio del petróleo se varió entre los 100 y 200 $/barril. This work presents an economical evaluation of implementing a solar air-conditioning system using solar energy in Havana, Cuba. It was studied the feasibility of systems of small and medium capacities (7-35 kW) of absorption refrigeration machines which be in the world market. The parameters that were taken for the feasibility were the payback time and life cycle savings. Also it was analyzed the influence of the ratio storage volume/solar collector area (V/A) on solar fraction, auxiliary energy, saved energy cost, saved primary energy and emitted CO2. Besides, it was used the P1-P2 method for the economical aspects and the Φ-fchart method in order to determine de solar fraction. The price of petroleum was varied from 100 to 200$/barrel.

Foram avaliadas neste trabalho a absorção foliar e a translocação do glyphosate por biótipos de azevém (Lolium multiflorum) sensíveis e resistentes a esse herbicida. Para isso, aplicou-se 14C-glyphosate utilizando-se uma microsseringa de precisão, adicionando-se 10 µL da calda sobre a face adaxial da primeira folha com lígula totalmente visível, quando as plantas de azevém se apresentavam com três perfilhos. A quantidade de glyphosate absorvido e translocado foi avaliada em intervalos de tempo (2, 4, 8, 16, 32 e 64 horas ap��s a aplicação), por meio da medição da radiação emitida pelo 14C-glyphosate, em espectrômetro de cintilação líquida. Foram analisadas a parte aérea e as raízes, bem como a folha onde foi feita a aplicação e a solução de lavagem desta folha. A velocidade de absorção do glyphosate foi semelhante em ambos os biótipos de azevém, observando-se mais de 50% de absorção desse herbicida nas primeiras oito horas após a aplicação. Maior retenção de glyphosate foi observada na folha tratada do biótipo resistente: 81,64% do total de glyphosate absorvido até as 64 horas. No biótipo sensível esse valor foi de 55% no mesmo período. No restante da parte aérea e nas raízes, a maior quantidade do glyphosate absorvido foi encontrada no biótipo sensível, mostrando sua maior capacidade de translocação. Após 64 horas da aplicação do glyphosate, apenas 6%, em média, do glyphosate se encontrava nas plantas, indicando que a maior parte do produto pode ter sido exsudada. Conclui-se que a sensibilidade do azevém ao glyphosate pode ser atribuída à maior capacidade de translocação desse herbicida pelo biótipo sensível.This work evaluated foliar absorption and glyphosate translocation in Italian ryegrass (Lolium multiflorum) susceptible and resistant biotypes, 14C-glyphosate was applied by using a precision micro syringe, and adding 10 µL of solution on the adaxial side of the first leaf with ligule totally visible, when Italian ryegrass plants showed 3 tillers. The quantity of glyphosate absorbed and translocated was evaluated through a liquid scintilation spectrometer by measuring radiation emitted by 14C-glyphosate at 2, 4, 8, 16, 32 and 64 hours after application. The roots and aerial part were analyzed as well as the leaf where application was performed and the solution used to wash the leaf. Glyphosate absorption speed was similar in both Italian ryegrass biotypes, with over 50% of herbicide absorption in the first 8 hours after application. Up to 64 hours, higher retention (81.64%)of glyphosate was observed in the resistant biotype, while only 55% was retained in the susceptible biotype. In the remaining aerial part and roots, a higher amount of glyphosate was absorbed by the susceptible biotype, indicating higher capacity of its translocation. After 64 hours of application, only 6%, of glyphosate was found in the plants, on average indicating that most of the product could be exuded. It could be concluded that Italian ryegrass sensitivity to glyphosate can be attributed to higher translocation capacity of this herbicide by susceptible biotypes.