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Ladolescentes de nuestro contexto, dando cuenta de una situación problemática que ha conducido a cuestionar las dinámicas que permean la formación de carácter e identidad de aquellos quienes la practican. En este sentido, como referencian Kirchner, Ferrer, Forns, & Zanini (2011), adolescentes de todo el mundo muestran prevalencia de comportamientos autolesivos en un 13% y según lo expuesto en el informe de la OMS de 2001 se referencia que las lesiones autoinfligidas, incluido el suicidio, causaron aproximadamente 814.000 muertes en el año 2000 en todo el mundo, situación que resulta preocupante en la medida en que evidentemente con el transcurrir de los años las cifras van en aumento y a diario se evidencian casos cada vez más complejos; ubicándose específicamente en nuestro contexto colombiano, donde temas de familias disfuncionales, identidad sexual, bullying, desordenes alimenticios, depresión, libertad de expresión, déficit en las estrategias de afrontamiento y la baja autopercepción de capacidades para manejar situaciones estresantes.

Using caged-Ca photorelease or paired depolarising pulses in voltage-clamped chromaffin cells (CCs), various pools of secretory vesicles with different readiness to undergo exocytosis have been identified. Whether these pools are present in unclamped CCs challenged with ACh, the physiological neurotransmitter at the splanchnic nerve-CC synapse, is unknown. We have explored here whether an ACh-sensitive ready-release vesicle pool (ASP) is present in C57BL6J mouse chromaffin cells (MCCs). Single cells were fast perfused with a Tyrode solution at 37°C, and challenged with 12 sequential ACh pulses (100 μm, 2 s, every 30 s) plus a K pulse given at the end (75 mm K). After the first 2–3 ACh pulses the amperometrically monitored secretory responses promptly decayed to a steady-state level of around 25% of the initial response. The last K pulse, however, overcame such decay. Repeated ACh pulses to voltage-clamped cells elicited non-desensitising nicotinic currents. Also, the [Ca] transients elicited by repeated ACh pulses that were superimposed on a stable baseline elevation did not undergo decay. The novel blocker of the mitochondrial Na/Ca exchanger (mNCX) ITH12662 prevented the decay of secretion elicited by ACh pulses and delayed the rate of [Ca] clearance. The experiments are compatible with the idea that C57BL6J MCCs have an ASP vesicle pool that is selectively recruited by the physiological neurotransmitter ACh and is regulated by the rate of Ca delivery from mitochondria to the cytosol, through the mNCX., This study was supported by grants from Ministerio de Economıa y Competitividad, Spain (MINECO SAF2013-44108-P to A.G.G. and L.G., BFU2014-55731-R, to M.M., and FPI-BES-2014-069005 to I.M.). We thank the continued supportof Fundacion Teofilo Hernando.

Upon repeated application of short ACh pulses to C57BL6J mouse chromaffin cells, the amperometrically monitored secretory responses promptly decayed to a steady-state level of around 25% of the initial response. A subsequent K+ pulse, however, overcame such decay. These data suggest that mouse chromaffin cells have a ready release-vesicle pool that is selectively recruited by the physiological neurotransmitter ACh. The ACh-sensitive vesicle pool is refilled and maintained by the rate of Ca2+ delivery from mitochondria to the cytosol, through the mitochondrial Na+ /Ca2+ exchanger (mNCX). ITH12662, a novel blocker of the mNCX, prevented the decay of secretion elicited by ACh pulses and delayed the rate of [Ca2+ ]c clearance. This regulatory pathway may be physiologically relevant in situations of prolonged stressful conflicts where a sustained catecholamine release is regulated by mitochondrial Ca2+ circulation through the mNCX, which couples respiration and ATP synthesis to long-term stimulation of chromaffin cells by endogenously released ACh.

Objetivo: analizar la incidencia de una estrategia de escritura colaborativa en línea de un texto multimodal en el aprendizaje de la escritura, el aprendizaje colaborativo y el aprendizaje de contenidos disciplinares de estudiantes universitarios en un curso virtual. -- Metodología: se realizó un estudio de caso en una asignatura de lengua de un programa universitario en modalidad virtual. Participaron 2 tutoras y 214 alumnos organizados en 43 grupos colaborativos, de los que se tomaron como muestra 12 grupos (60 estudiantes). Las técnicas de recolección de la información utilizadas fueron el registro audiovisual, el análisis documental de los foros y las wikis y los textos producidos por los estudiantes, así como las entrevistas a las docentes. -- Resultados: se encontró que la estrategia de escritura colaborativa en línea incidió positivamente en los procesos de aprendizaje de los participantes en lo relacionado con el trabajo colaborativo, la lengua, la temática planteada para el producto y las herramientas de las TIC utilizadas en su ejecución. Asimismo, se encontraron dificultades en las características multimodales de los productos elaborados. Se resalta el potencial encontrado en la escritura colaborativa en línea, condicionado a los procesos de diseño y a la mediación de las actividades. Objective: This paper examines the impact of online collaborative writing of multimodal texts, completed during a virtual course for university students, on the participants’ writing skills, their experience of collaborative learning and their disciplinary literacy. -- Methodology: The paper reports on a case study of university students who participated in an online language learning course. The course was led by two tutors and completed by 214 students organized in 43 collaborative groups, of which 12 (60 students) were sampled. The authors collected their data from audiovisual recordings, documental analyses of the forums, wikis and student-generated texts, and interviews with the tutors. -- Results: The study found that the collaborative writing activities had a positive effect on the students’ learning process, specifically on their ability to engage in collaborative work, their language learning (the subject of the course), the quality of attention given to the topics that emerged in the writing activities and the students’ use of ITC tools. On the other hand, the study also observed that there were certain shortcomings in the texts produced during the course and that these were directly related to the multimodal character of the texts. The authors conclude that online collaborative writing can positively contribute to student learning when and where this is favoured by the design of the writing tasks and the choice of activities.

Objectiu: analitzar la incidència d'una estratègia d'escriptura col·laborativa en línia d'un text multimodal en l'aprenentatge de l'escriptura, l'aprenentatge col·laboratiu i l'aprenentatge de continguts disciplinaris d'estudiants universitaris en un curs virtual. Metodologia: es va dur a terme un estudi de cas en una assignatura de llengua d'un programa universitari en modalitat virtual. Van participar-hi dues tutores i dos-cents catorze alumnes organitzats en quaranta-tres grups col·laboratius, dotze dels quals (seixanta estudiants) es van prendre com a mostra. Les tècniques de recol·lecció de la informació utilitzades van ser el registre audiovisual, l'anàlisi documental dels fòrums i els wikis, i els textos produïts pels estudiants, així com també les entrevistes a les docents. Resultats: es va trobar que l'estratègia d'escriptura col·laborativa en línia va incidir positivament en els processos d'aprenentatge dels participants pel que fa al treball col·laboratiu, la llengua, la temàtica plantejada per al producte i les eines de les TIC utilitzades en l'execució. Així mateix, es van trobar dificultats en les característiques multimodals dels productes elaborats. Es ressalta el potencial trobat en l'escriptura col·laborativa en línia, condicionat als processos de disseny i a la mediació de les activitats., Objective: This paper examines the impact of online collaborative writing of multimodal texts, completed during a virtual course for university students, on the participants’ writing skills, their experience of collaborative learning and their disciplinary literacy. Methodology: The paper reports on a case study of university students who participated in an online language learning course. The course was led by two tutors and completed by 214 students organized in 43 collaborative groups, of which 12 (60 students) were sampled. The authors collected their data from audiovisual recordings, documental analyses of the forums, wikis and student-generated texts, and interviews with the tutors. Results: The study found that the collaborative writing activities had a positive effect on the students’ learning process, specifically on their ability to engage in collaborative work, their language learning (the subject of the course), the quality of attention given to the topics that emerged in the writing activities and the students’ use of ITC tools. On the other hand, the study also observed that there were certain shortcomings in the texts produced during the course and that these were directly related to the multimodal character of the texts. The authors conclude that online collaborative writing can positively contribute to student learning when and where this is favoured by the design of the writing tasks and the choice of activities., Objetivo: analizar la incidencia de una estrategia de escritura colaborativa en línea de un texto multimodal en el aprendizaje de la escritura, el aprendizaje colaborativo y el aprendizaje de contenidos disciplinares de estudiantes universitarios en un curso virtual. Metodología: se realizó un estudio de caso en una asignatura de lengua de un programa universitario en modalidad virtual. Participaron 2 tutoras y 214 alumnos organizados en 43 grupos colaborativos, de los que se tomaron como muestra 12 grupos (60 estudiantes). Las técnicas de recolección de la información utilizadas fueron el registro audiovisual, el análisis documental de los foros y las wikis y los textos producidos por los estudiantes, así como las entrevistas a las docentes. Resultados: se encontró que la estrategia de escritura colaborativa en línea incidió positivamente en los procesos de aprendizaje de los participantes en lo relacionado con el trabajo colaborativo, la lengua, la temática planteada para el producto y las herramientas de las TIC utilizadas en su ejecución. Asimismo, se encontraron dificultades en las características multimodales de los productos elaborados. Se resalta el potencial encontrado en la escritura colaborativa en línea, condicionado a los procesos de diseño y a la mediación de las actividades.

En el marco de la iniciativa Ingeniería para las Américas (EFTA, Engineering for the Americas), programa que establece las necesidades de mejoramiento y modernización de la enseñanza de la ingeniería en los países miembros de la Organización de Estados Americanos (OEA), se llevó a cabo el estudio prospectivo de la Ingeniería Química al 2025. El estudio tiene como objetivo el identificar y priorizar nuevas tendencias, temas, tecnologías, criterios de calidad para la Ingeniería Química para el año 2025. El estudio prospectivo fue realizado consultando a expertos nacionales e internacionales a través de tres rondas Delphi, por medio de un documento digital enviado por correo electrónico. El estudio se centró en el análisis de siete áreas medulares de la ingeniería química: tecnologías, líneas de formación, ingeniería de sistemas de procesos, fenómenos de transporte y operaciones unitarias, fisicoquímica y termodinámica, química e ingeniería de las reacciones y criterios de calidad para la educación en ingeniería química. El estudio arrojó en total 85 temas prioritarios. In the framework of the Engineering for the Americas program (EFTA), that establishes the need for the quality improvement and modernization of engineering education in member countries of the Organization of American States (OAS), a prospective study of chemical engineering by 2025 was performed. The objective of the study is identifying and prioritizing new tendencies, topics, technologies and quality criteria for the chemical engineering profession. The prospective study was done consulting national and international experts through three Delphi rounds by submitting a document via email. The study focused on analysing seven core areas of chemical engineering: technologies, formation lines, systems process engineering, transportation phenomena and unit operations, physical chemistry and thermodynamics, chemistry and reaction engineering, quality criteria for education in chemical engineering. The study covered 85 priority issues.

The wide variety of excipients available calls for evaluation of their functionality, in this case of the pharmaceutical performance of microcrystalline celluloses and sodium cross-linked carboxymethylcelluloses from different sources. This evaluation includes parameters such as powder flow, compactibility, ejection pressure and dissolution from fast-release tablets as well as from floating granules and controlled-release tablets. In a previous study, the excipient Carmacel® presented better disintegration properties compared to Croscarmellose®. However, the evaluation showed better compactibility performance for Croscarmellose®. These characteristics were observed using pure excipients. Nevertheless, these advantages have not been confirmed in tests employing immediate-release or modified-release formulations containing metronidazole. Regarding microcrystalline celluloses, the present comparative evaluation between pure Alfacel ® types 101 and 102 and pure Avicel® types 101 and 102 showed better compactibility performance for the latter. However, for metronidazole formulations, this advantage was not evident in the innovative excipient. Notwithstanding, this study revealed better compactibility performance of microcrystalline cellulose type 101. In terms of powder flow properties, Avicel® and Alfacel® showed similar performance. However, the results revealed better powder flow employing microcrystalline cellulose type 102 for both excipients. Based on the results obtained, it can be concluded that the employment of innovative and generic excipients have both advantages and disadvantages. The observed differences however, tend to disappear as the excipients are diluted in a formulation, thereby equalizing their influence on product performance.A variedade de excipientes disponível no mercado requer adequada seleção desses no que se refere à sua funcionalidade, como no caso de celuloses microcristalinas (Avicel® 101 e 102 e Alfacel® 101 e 102) e de carboximetilceluloses de sódio reticuladas (Croscarmellose® e Carmacel®), provenientes de diferentes fontes. Assim sendo, o desempenho farmacotécnico desses excipientes deve ser avaliado quanto ao fluxo e característica de compactação do pó, à pressão de expulsão do núcleo, ao perfil de dissolução de comprimidos de liberação imediata e modificada assim como de grânulos flutuantes. Em um trabalho anterior, o excipiente Carmacel® apresentou melhores propriedades de desintegração quando comparado ao Croscarmellose®, porém, no que se refere à característica de compactação a avaliação revelou melhor desempenho para o Croscarmellose®. Tais características foram observadas empregando apenas os excipientes. Porém, tais vantagens não foram confirmadas nos ensaios empregando as formulações de liberação imediata ou de liberação modificada contendo metronidazol. No que se refere às celuloses microcristalinas, a avaliação comparativa entre Alfacel® puro dos tipos 101 e 102 e Avicel® puro dos tipos 101 e 102 revelou melhor desempenho desse último quanto à característica de compactação, no entanto, para as formulações contendo metronidazol não foi possível demonstrar tal vantagem para o excipiente inovador. Porém, o estudo revelou melhor desempenho quanto à característica de compactação da celulose microcristalina do tipo 101. Quanto às propriedades relativas ao fluxo de pó, o Avicel® e o Alfacel® apresentaram desempenho semelhante. Porém, o estudo revelou melhor fluxo de pó no emprego da celulose microcristalina do tipo 102, para ambos os excipientes. Considerando os resultados obtidos, pode-se concluir que o emprego dos excipientes inovador e genérico apresentam vantagens e desvantagens. No entanto, as diferenças observadas tendem a desaparecer em função da diluição desses na formulação, equalizando, dessa forma, sua influência no desempenho do produto.