Los proyectos telemáticos en los centros educativos.

El artículo forma parte de una sección de la revista dedicada a innovación educativa, en este número, al aprendizaje colaborativo a través de la Red.

El uso de las prácticas de laboratorio de física y química en dos contextos educativos diferentes: Alemania y España.

El trabajo forma parte del proyecto: Hacia la Convergencia Europea: una oportunidad para mejorar la docencia en el Área de Ciencias, un estudio comparativo de la enseñanza de la Física y la Química en la educación secundaria en Alemania y España. Se ha investigado la opinión de cuatro colectivos: equipos directivos, profesorado, alumnado y familias. Los resultados obtenidos ponen en evidencia importantes diferencias en la enseñanza formal y no formal de la física y la química en ambos contextos. Algunas de las diferencias puestas de manifiesto se derivan de elementos organizativos o de dotación de recursos pero otras son consecuencia de concepciones y creencias sobre la enseñanza y la educación, sobre formación del profesorado, reconocimiento social de la función docente y profesional..

Parental permissiveness, control, and affect and drug use among adolescents

Resumen tomado de la publicación

La ciudad colonial andina en los ojos de Guamán Poma de Ayala (Estudios)

En su célebre Nueva Corónica y Buen Gobierno, Felipe Guaman Poma de Ayala dejó estampada una visión propia del urbanismo colonial. El autor de este estudio realiza un análisis tanto del texto escrito como de los dibujos que el cronista indígena compuso, con el fin de mostrar que ellos traducen una compleja y rica combinación de descripción de la red urbana realmente existente a inicios del siglo XVII, con una serie de ideales de ordenamiento espacial, urbanístico y geográfico, propio de los imaginarios andinos. Así, el orden de las calles y plazas en damero, con la iglesia en el centro, se combina con la afirmación de jerarquías de la red de lugares centrales del mundo prehispánico.

Vigencia de La novela ecuatoriana, de Ángel F. Rojas (Dossier: Cuatro narradores del 30, relecturas en su centenario)

Luego de ubicar a Ángel F. Rojas entre los ensayistas de temas literarios de su generación, la autora sustenta la vigencia del crítico lojano. Más allá de que no exista, en el siglo XX, ningún otro estudio de similar alcance sobre la novela ecuatoriana, plantea que los méritos de esta obra radican en los criterios de periodización empleados, en que los juicios emitidos se sustentan en criterios estéticos, y en que jerarquiza las obras de acuerdo a su valor literario, no se trata de crítica impresionista o biografista, ni sesgada negativamente por consideraciones ideológicas. Rojas incluye, entonces, tres rasgos propios de la moderna crítica literaria: el deslinde, el establecimiento de jerarquías y la emisión de juicios sustentados en la literaturidad de las obras. Un buen número de las conclusiones del autor mantiene actualidad, igual ocurre con la significación de muchas de ellas en el canon del país. El texto de Rojas inicia la moderna crítica literaria ecuatoriana, y mantiene su lugar referencial entre los estudios de la novela en este país.

Lidiando con la diferencia. Respuestas desde la justicia constitucional ecuatoriana y colombiana (Tema Central)

Este artículo asume que uno de los problemas contemporáneos más acuciantes es la enorme dificultad de relacionarnos con la diferencia, cualquiera que esta sea, y de construir formas de convivencia que superen las visiones dominantes basadas en las jerarquizaciones. el derecho no es ajeno a esta interpelación. En cada sentencia encontramos una disputa para dar sentido y significado a los derechos que están en juego en el caso concreto, tal disputa está ligada a las creencias, ideologías, formas de entender el mundo de quienes juzgan. es así que en este estudio analizo sentencias emitidas por las cortes constitucionales de ecuador y Colombia, para ensayar contestaciones a la interrogante: ¿Cómo responde la justicia constitucional ecuatoriana y colombiana en los casos que afronta la diferencia?

Modeling Habitat Associations for the Common Loon (Gavia immer) at Multiple Scales in Northeastern North America

Common Loon (Gavia immer) is considered an emblematic and ecologically important example of aquatic-dependent wildlife in North America. The northern breeding range of Common Loon has contracted over the last century as a result of habitat degradation from human disturbance and lakeshore development. We focused on the state of New Hampshire, USA, where a long-term monitoring program conducted by the Loon Preservation Committee has been collecting biological data on Common Loon since 1976. The Common Loon population in New Hampshire is distributed throughout the state across a wide range of lake-specific habitats, water quality conditions, and levels of human disturbance. We used a multiscale approach to evaluate the association of Common Loon and breeding habitat within three natural physiographic ecoregions of New Hampshire. These multiple scales reflect Common Loon-specific extents such as territories, home ranges, and lake-landscape influences. We developed ecoregional multiscale models and compared them to single-scale models to evaluate model performance in distinguishing Common Loon breeding habitat. Based on information-theoretic criteria, there is empirical support for both multiscale and single-scale models across all three ecoregions, warranting a model-averaging approach. Our results suggest that the Common Loon responds to both ecological and anthropogenic factors at multiple scales when selecting breeding sites. These multiscale models can be used to identify and prioritize the conservation of preferred nesting habitat for Common Loon populations.

Organizational analysis of building projects

The principles of organization theory are applied to the organization of construction projects. This is done by proposing a framework for modelling the whole process of building procurement. This consists of a framework for describing the environments within which construction projects take place. This is followed by the development of a series of hypotheses about the organizational structure of construction projects. Four case studies are undertaken, and the extent to which their organizational structure matches the model is compared to the level of success achieved by each project. To this end there is a systematic method for evaluating the success of building project organizations, because any conclusions about the adequacy of a particular organization must be related to the degree of success achieved by that organization. In order to test these hypotheses, a mapping technique is developed. The technique offered is a development of a technique known as Linear Responsibility Analysis, and is called "3R analysis" as it deals with roles, responsibilities and relationships. The analysis of the case studies shows that they tended to suffer due to inappropriate organizational structure. One of the prevailing problems of public sector organization is that organizational structures are inadequately defined, and too cumbersome to respond to environmental demands on the project. The projects tended to be organized as rigid hierarchies, particularly at decision points, when what was required was a more flexible, dynamic and responsive organization. The study concludes with a series of recommendations; including suggestions for increasing the responsiveness of construction project organizations, and reducing the lead-in times for the inception periods.

Flavour characterization of fresh and processed pennywort (Centella asiatica L.) juices

The flavour characteristics of fresh and processed pennywort juices treated by pasteurization, sterilization and high pressure processing (HPP) were investigated by using solid-phase micro-extraction combined with gas chromatography-mass spectrometry. Sesquiterpene hydrocarbons comprised the major class of volatile components present and the juices had a characteristic smell due to the presence of volatile compounds including β-caryophyllene, humulene, E-β-farnesene, α-copaene, alloaromadendrene and β-elemene. All processing operations caused a reduction in the total volatile concentration, but HPP caused more volatile acyclic alcohols, aldehydes and oxygenated monoterpenoids to be retained than pasteurization and sterilization. Ketones were not present in fresh pennywort juice, but 2-butanone and 3-nonen-2-one were generated in all processed juices, and 2-nonanone and 2-hexanone were present in pasteurized and sterilized juices. Other chemical changes including isomerization were also reduced by HPP compared to pasteurization, and sterilization.

Phenolic contents of lettuce, strawberry, raspberry, and blueberry crops cultivated under plastic films varying in ultraviolet transparency

The levels of health-related phytochemicals were determined in lettuce leaf and in strawberry, raspberry and blueberry fruits grown in near-commercial conditions under plastic films of three different UV transparencies. In the red lettuce Lollo Rosso, total phenolics, anthocyanin, luteolin and quercetin levels were all raised by changing from a UV blocking film to a film of low UV transparency, and to a film of high UV transparency. The related green lettuce, Lollo Biondo, cultivated under the same conditions, showed virtually no phytochemical responses to the same variation in UV levels. Overall, the phenolic levels of strawberries, raspberries, and blueberries were unresponsive to the UV transparency of the plastic film under which the crops were grown. The significance of these findings is discussed in relation to the nutritional quality of soft fruit and salad crops which are increasingly being grown commercially under plastic tunnels.

Effects of chlorogenic acid and bovine serum albumin on the oxidative stability of low density lipoproteins in vitro

The ability of chlorogenic acid to inhibit oxidation of human low-density lipoprotein (LDL) was studied by in vitro copper-induced LDL oxidation. The effect of chlorogenic acid on the lag time before LDL oxidation increased in a dose dependent manner by up to 176% of the control value when added at concentrations of 0.25 -1.0 μM. Dose dependent increases in lag time of LDL oxidation were also observed, but at much higher concentrations, when chlorogenic acid was incubated with LDL (up to 29.7% increase in lag phase for 10 μM chlorogenic acid) or plasma (up to 16.6% increase in lag phase for 200 μM chlorogenic acid) prior to isolation of LDL, and this indicated that chlorogenic acid was able to bind, at least weakly, to LDL. Bovine serum albumin (BSA) increased the oxidative stability of LDL in the presence of chlorogenic acid. Fluorescence spectroscopy showed that chlorogenic acid binds to BSA with a binding constant of 3.88 x 104 M-1. BSA increased the antioxidant effect of chlorogenic acid, and this was attributed to copper ions binding to BSA, thereby reducing the amount of copper available for inducing lipid peroxidation.

Development of a capillary electrophoresis method for the simultaneous analysis of artificial sweeteners, preservatives and colours in soft drinks

A rapid capillary electrophoresis method was developed simultaneously to determine artificial sweeteners, preservatives and colours used as additives in carbonated soft drinks. Resolution between all additives occurring together in soft drinks was successfully achieved within a 15-min run-time by employing the micellar electrokinetic chromatography mode with a 20 mM carbonate buffer at pH 9.5 as the aqueous phase and 62 mM sodium dodecyl sulfate as the micellar phase. By using a diode-array detector to monitor the UV-visible range (190-600 nm), the identity of sample components, suggested by migration time, could be confirmed by spectral matching relative to standards.