Efecto de extracto de orégano sobre características fisicoquímicas y estructurales de un gel cárnico a base de calamar gigante durante su vida útil

Tesis de Maestría en Ciencias QuímicasEl calamar gigante (Dosidicus gigas) es un molusco de importancia económica en México, el 80% de esta especie se considera comestible, a pesar de que es una especie con alto contenido proteico (~18%) y bajo contenido de colesterol, la alta actividad enzimática que posee (enzimas endógenas y microbianas) genera una degradación proteica y por consecuencia, un descenso en las propiedades funcionales desde el punto de vista estructural. El objetivo del presente trabajo fue el desarrollo de un gel cárnico a base de esta especie y evaluar el efecto de la aplicación de un extracto acuoso de orégano durante el almacenamiento en refrigeración. Se evaluaron 4 métodos de extracción proteica; el proceso denominado B presentó las características apropiadas para el desarrollo del gel. Se adicionó el extracto de orégano (obtenido empleando una relación orégano-agua 1:15 y un tiempo de agitación de 15 min a 20°C) en un 5% v/v respecto a la disolución proteica a gelificar. La adición del extracto disminuyó la producción de bases volátiles y trimetilamina durante el almacenamiento. En cuanto al desarrollo microbiológico, existe una diferencia de 0.4 unidades logarítmicas en cuanto al conteo de mesófilos aerobios y de 2.7 unidades logarítmicas en el conteo de coliformes totales, ambas a favor de la muestra con extracto. Respecto a las características estructurales, no existe diferencia significativa entre las muestras, con y sin extracto, en el parámetro de dureza al final del almacenamiento. La adición de extracto acuoso de orégano permitió mantener las características fisicoquímicas y microbiológicas del gel durante el periodo de almacenamiento.Conacy

Analytical and numerical simulations of an Oscillating Water Column with humidity in the air chamber

This paper examines an Oscillating Water Column (OWC) model, where the air chamber is represented as a dry air–water vapour mixture, based on the thermodynamics of a real gas. The novelty of this study consists of the inclusion of humidity effects on the general performance of the OWC and its coupling with the radiation–diffraction problem of the device. Using FLUENT®, a numerical 2D flume is built to simulate wave–induced flow in the OWC. Air phase properties are adjusted to represent the presence of moisture. Turbine linear performance, according to a standard Wells turbine power take–off system, is simulated by means of an Actuator Disk Model (ADM). Numerical outputs are compared with analytical solutions of the classic OWC radiation–diffraction problem, in which the theoretical real gas model is embedded. Results show that the use of real gas thermodynamic theory reduces considerably the predicted power output of OWC devices, with theoretical losses reaching 50% in certain cases. The effect of humidity mitigates resonant conditions. Techno–economic considerations justify the inclusion of real gas theory to achieve competitive devices

Thermodynamics of an OWC containing real gas

Oscillating Water Column (OWC) devices are usually modelled as simple systems containing ideal, dry air. However, high humidity levels are likely to occur in a prototype device open to the sea, particularly in warm climates such as prevail in the lower latitudes. In this paper, a real gas model is implemented to take into account humidity variations inside an OWC chamber. Using a modified adiabatic index, theoretical expressions are derived for the thermodynamic state variables including enthalpy, entropy and specific heat. The model is validated against experimental data, and shown to provide better agreement than obtained using the ideal gas assumption. By calculating real air flow in an OWC it is shown that the mechanical efficiency reduces and the flow phase alters with respect to the ideal gas case. Accurate prediction of efficiency is essential for the optimal design and management of OWC wave energy converters

An analysis of the direct and mediated effects of employee commitment and supply chain integration on organisational performance

This paper focuses on the interrelationships among the different dimensions of supply chain integration. Specifically, it examines the relationship between employee commitment and supply chain integration dimensions to explain several performance measures, such as flexibility, delivery, quality, inventory and customer satisfaction. Very little research has been conducted onto this topic, since employee commitment is rarely included as an antecedent of the effect of supply chain integration on performance. Seven research models have been analysed with Structural Equation Models using a multiple-informant international sample of 266 mid-to-large-size manufacturing plants. The findings suggest that the relationship between employee commitment and operational performance is fully mediated by supply chain integration. Employee commitment contributes to improving internal integration, and internal integration affects performance both directly and indirectly. Moreover, obtaining internal integration helps to achieve supplier and customer integration. As a result, companies should strive to achieve both employee commitment and internal integration, as they mutually reinforce each other. Similarly, managers should achieve internal integration before external integration and include external integration at the strategic level in order to reap the greatest advantages from supply chain integration. Meanwhile, managers should promote employee commitment not only for better supply chain success, but also to mitigate the barriers of supply chain management implementation.This paper has been made possible thanks to Grants DPI2009-11148 and DPI2010-18243 awarded by the Spanish Ministry of Science and Innovation and the Project of Excelence P08 SEJ 3841 awarded by the Junta de Andalucia.Alfalla-Luque, R.; Marín García, JA.; Medina-Lopez, C. (2014). An analysis of the direct and mediated effects of employee commitment and supply chain integration on organisational performance. International Journal of Production Economics. (162):242-257. https://doi.org/10.1016/j.ijpe.2014.07.004S24225716

IN VITRO EQUIVALENCE STUDY OF DIFFERENT DOSES OF CARBAMAZEPINE REFERENCE TABLETS USING USP APPARATUSES 2 AND 4

Objective: To perform an in vitro equivalence study of two doses of carbamazepine reference tablets sold in the local market under hydrodynamic conditions of USP Apparatus 4, a dissolution apparatus that better simulates the human gastrointestinal tract. Results were compared with dissolution official conditions using USP Apparatus 2. Methods: Dissolution profiles of both formulations were carried out with an automated USP Apparatus 2 at 75 rpm and 900 ml of dissolution medium. USP Apparatus 4 with laminar flow at 16 ml/min and 22.6 mm cells were used. 1% lauryl sulfate aqueous solution at 37.0±0.5 °C was used as dissolution medium. Spectrophotometric determination of drug at 285 nm was carried out during 60 min. Dissolution profiles were compared with model-independent and-dependent approaches. Results: When comparing dissolution profiles of low vs. high dose similar profiles were found (f2>50) in each dissolution apparatus, however, when the same dose was compared, USP 2 vs. USP 4, opposite results were obtained. Comparison of mean dissolution time and dissolution efficiency data corroborates these results. Weibull function was the best mathematical model that described the in vitro dissolution performance of carbamazepine. No significant differences were found in Td values (low vs. high dose) but opposite results were also found with USP 2 vs. USP 4. Conclusion: Equivalent dissolution performance of two doses of carbamazepine reference tablets were found in each USP dissolution apparatus. The main problem identified in this comparative study is the low dissolution rate and extent found with USP Apparatus 4. More research on this field is necessary for all available doses of reference drug products since the quality of generic formulations depends on the quality of references

INFLUENCE OF DOSE AND USP DISSOLUTION APPARATUS IN THE RELEASE PERFORMANCE OF REFERENCE TABLETS: PROPRANOLOL-HCl AND RANITIDINE-HCl CASES

Objective: Due to quality of generic formulations depends on available information of reference drug products the aim of this work was to perform an in vitro dissolution study of two doses of propranolol-HCl and ranitidine-HCl reference tablets using USP basket or paddle apparatus and flow-through cell method. Methods: Two doses of propranolol-HCl (10-mg and 80-mg) and ranitidine-HCl (150-mg and 300-mg) of Mexican reference products were used. Dissolution profiles of propranolol-HCl were obtained with USP basket apparatus at 100 rpm and 1000 ml of 1% hydrochloric acid. Profiles of ranitidine-HCl were determined with USP paddle apparatus at 50 rpm and 900 ml of distilled water. All formulations were also studied with the flow-through cell method using laminar flow at 16 ml/min. Dissolution profiles were compared by model-independent (f2 similarity factor, mean dissolution time and dissolution efficiency) and model-dependent methods (dissolution data adjusted to some mathematical equations). Time data, derived from these adjustments, as t50%, t63.25%, and t85% were used to compare dissolution profiles. Results: With all approaches used and being high solubility drugs significant differences were found between low and high doses and between USP dissolution apparatuses (*P<0.05). Conclusion: In vitro dissolution performance of two doses of propranolol-HCl and ranitidine-HCl was not expected. Considering the same USP dissolution apparatus, the reference tablets did not allow the simultaneous release of the used doses. The results could be of interest for pharmaceutical laboratories or health authorities that classify some drug products as a reference to be used in dissolution and bioequivalence studies

Significado psicológico de respeto entre adolescentes

El objetivo de este trabajo fue conocer el significado psicológico de "respeto" entre adolescentes, y a quién se le debe tener respeto y por qué. Se trabajó con 100 estudiantes de Preparatoria, distribuidos equitativamente por género, mediante la utilización de la técnica de redes semánticas naturales. Los resultados muestran que ambos géneros definieron respeto como un valor, honestidad, igualdad, confianza, educación, lealtad, tolerancia y humildad. Las diferencias muestran que para el género masculino, el respeto es amabilidad, moral, solidaridad, personalidad, trabajo, personas y libertad, en comparación con el género femenino, que lo define como amor, valorar, sinceridad, amistad, facultad, apreciar y virtud. Respecto de a quién se le debe tener respeto, ambos géneros coincidieron al decir que se debe respetar a los padres, a uno mismo, a la religión, a los viejos, los amigos, la familia, los semejantes, los maestros, la pareja, la naturaleza y la sociedad. En el caso del género masculino, éste tiende a respetar también a los niños, los animales y las opiniones, en contraste con el femenino, que respeta la vida, los hijos y las cosas. Tales resultados dejan ver que, en México, entre los hombres prevalece la instrumentalidad, al considerar, entre otras cosas, que el respeto está ligado a la libertad y al trabajo, en comparación con las mujeres, que tienden a ser más expresivas, ya que relacionan el respeto con el amor y la amistad

¿Es necesario el compromiso de los trabajadores para alcanzar ventajas competitivas y satisfacción del cliente cuando las compañías emplean prácticas de HRM y TQM?

[EN] There is mounting interest in both theory and practice regarding the relationship between Human Resource Management (HRM) and Total Quality Management (TQM), as well as the relationship between HRM and TQM and organisational performance. This paper focuses on the empirical explanation of the role of commitment as a form of mediation between the HRM or TQM practices and company competitiveness (competitive advantage and customer satisfaction). Light is also shed on the interrelationship between HRM and TQM practices testing the scope of influence of each HRM practice on TQM implementation, including the effect of HRM on individual TQM practices.[ES] Hay un creciente interés, tanto en los aspectos teóricos como en los prácticos, sobre la relación entre la gestión de los recursos humanos (HRM) y la gestión de la calidad total (TQM), así como sobre la relación entre HRM y TQM y los resultados empresariales. Este artículo realiza un estudio empírico que analiza el papel del compromiso de los trabajadores como variable mediadora entre las prácticas de HRM y TQM y la competitividad de la empresa (ventaja competitiva y satisfacción del cliente). También se analiza la relación entre las prácticas de HRM y TQM, determinando el efecto que cada práctica individual de HRM tiene sobre la implementación de TQM, así como el efecto en HRM de cada práctica de TQM.This paper has been made possible thanks to grant DPI2006-05531 (HPM Project-Spain: Project for high performance manufacturing) awarded by the Spanish Ministry of Education and Science and the project “CORSARI MAGIC DPI2010-18243” by the Spanish Ministry of Science and Innovation within the Program “Proyectos de Investigación Fundamental No Orientada”.Alfalla Luque, R.; Marín García, JA.; Medina Lopez, C. (2012). Is worker commitment necessary for achieving competitive advantage and customer satisfaction when companies use HRM and TQM practices?. Universia Business Review. (36):64-89. http://hdl.handle.net/10251/45837S64893

Hydrogeochemical characteristics of a volcanic-sedimentary aquifer with special emphasis on Fe and Mn content: A case study in Mexico

Previous studies performed on the volcanic-sedimentary aquifer of the Tenancingo Valley (Mexico) reports high concentrations of Fe, Mn, and NO3 −, and water from several wells receives purification treatments due to presence of Fe and Mn. These studies have not achieved conclusive results regarding the origin of Fe and Mn, nor have hydrogeochemical evaluations of the aquifer been performed. The present study aimed to evaluate the physicochemical characteristics of the water and identify the geochemical processes that determine presence of Fe and Mn in groundwater. This characterization was based on physicochemical data from well and spring samples (16 samples) during dry and rainy seasons (June and November 2012, respectively). The EC, temperature and pH ranged from 125 to 793 μS cm−1 , 14.5 to 24.9 °C and 6.5 to 8.5 pH units, respectively. The Eh values ranged from −219 to 327 mV, indicating the existence of both reducing and oxidizing zones. Presence of Fe and Mn was detected in both springs and wells; concentrations were higher in well, exceeding 4 mg Fe L−1 and 0.5 mg Mn L−1 . Content of Si ranged from 12 to 47 mg L−1 . A model of the hydrogeochemical behavior of the aquifer was created to highlight the following: i) processes involved in water-rock interactions, including fluctuations in silicate levels that determine anionic and cationic content of water, and ii) redox reactions as the major control processes of Fe and Mn. Water quality for human use is restricted by Fe and Mn content and pH. For irrigation use, significant limitations were not presente

Criterios de implementación ISO 14001:2015 Caso Estudio Sector de construcción.

Criterios de implementación ISO 14001:2015 Caso Estudio Sector de construcción.El presente estudio de caso tiene como finalidad identificar y mostrar la importancia de implementar un Sistema de Gestión Ambiental, como herramienta para identificar impactos ambientales potenciales, que se pueden generar durante el desarrollo de los procesos que se ejecutan en el sector de la construcción. Cada día, esta metodología se convierte en una herramienta importante también para que el proceso de creación de un producto este basado en oportunidades de mejora en el desempeño ambiental de productos (ICONTEC, 2007) y posteriormente enfocarlo hacia la producción más limpia factor de importancia no solo para evidenciar el cumplimiento ambiental de una empresa sino además que influye como valor agregado a los productos o actividades que se desarrollan en la misma, lo que conlleva a mejorar el mercadeo del mismo. Teniendo en cuenta que hoy en día resulta importante la reflexión que se hace acerca del uso de los recursos naturales se busca que los productos y procesos sean amigables con el ambiente y esto quiere decir, no solo que se evidencie el control de los impactos que se generen sino también, que durante todo el procesos se haga control a estos factores que pueden generar entre otras, el agotamiento de los recursos naturales.The purpose of this case study is to identify and show the importance of implementing an Environmental Management System, as a tool to identify potential environmental impacts, which can be generated during the development of the processes that are carried out in the construction sector. Each day, this methodology becomes an important tool also for the process of creating a product is based on opportunities to improve the environmental performance of products (ICONTEC, 2007) and then focus on cleaner production factor of importance not only to show the environmental compliance of a company but also that it has an added value to the products or activities that are developed in it, which leads to improve the marketing of the same. Taking into account that nowadays it is important the reflection that is made about the use of natural resources, we look for the products and processes to be friendly with the environment and this means, not only that the control of the impacts is evident. generate but also, that throughout the process control is made to these factors that can generate, among others, the depletion of natural resources