927 resultados para Porter, Michael
Resumo:
En el mundo cada cinco minutos se produce un suicidio en adolescentes por problemas inherentes a su sexualidad. Frente a este escenario la genealogía de los discursos médico, jurídico y literario se entreteje apretando los hilos, convirtiéndose en cábala del suicidio; un reflejo difuso de una realidad menos ficcional y más dolorosa. A pesar de las cifras alarmantes, no se ha trabajado el tema; menos aún con la perspectiva de encontrar relación entre los discursos históricos que en su búsqueda de poder y control han dibujado sobre los cuerpos, representaciones de una disciplina heterosexual. Es indispensable una perspectiva cualitativa, reflexiones que aporten a una práctica ética diferente, que incluya los nuevos cuerpos filosóficos, legales, concibiendo al adolescente como sujeto, con la agencia que deben tener sus cuerpos. En contraste en la literatura (¿mundo ficticio?) se describe y resignifica de manera exhaustiva esta realidad, rescatando la capacidad creativa y re-creativa del lenguaje. Esto por un lado permite analizar los contextos y coyunturas sociales, culturales; y, por otro interpretar los imaginarios sociales y las metáforas que refuerzan este contexto. Como mencionara Stuart Hall, a través de la representación conectamos el lenguaje al sentido y la cultura. Y esto nos licencia a referirnos al mundo real pero también a un mundo ficticio. Esta exploración pretende aportar a esta problemática mediante la descripción de esa compleja interseccionalidad y la identificación de posibles intersticios en el lenguaje que pudieran dar sentido y descodificar ciertas incertidumbres, contribuir a cambios micro sociales y, quizás, conducir a lo que pudiera ser el comienzo de un diálogo más amplio que empuje posicionamientos y cambios estructurales, frente a discursos vetustos que siempre encuentran mecanismos para reinventarse. ¿Cómo se representan y entretejen los discursos de homoerotismo1 adolescente y suicidio representados en las novelas Conquering Venus de Collin Kelley, Suicide Notes de Michael Thomas Ford? Lo podremos averiguar examinando las matrices discursivas del homoerotismo y su castigo, la homosexualidad; analizando el suicidio como un acto humano complejo, incomprensible, un tabú en nuestra sociedad, e identificando en las novelas escogidas, las intersecciones entre homoerotismo y tendencias suicidas en el cuerpo adolescente.
Resumo:
Different systems, different purposes – but how do they compare as learning environments? We undertook a survey of students at the University, asking whether they learned from their use of the systems, whether they made contact with other students through them, and how often they used them. Although it was a small scale survey, the results are quite enlightening and quite surprising. Blackboard is populated with learning material, has all the students on a module signed up to it, a safe environment (in terms of Acceptable Use and some degree of staff monitoring) and provides privacy within the learning group (plus lecturer and relevant support staff). Facebook, on the other hand, has no learning material, only some of the students using the system, and on the face of it, it has the opportunity for slips in privacy and potential bullying because the Acceptable Use policy is more lax than an institutional one, and breaches must be dealt with on an exception basis, when reported. So why do more students find people on their courses through Facebook than Blackboard? And why are up to 50% of students reporting that they have learned from using Facebook? Interviews indicate that students in subjects which use seminars are using Facebook to facilitate working groups – they can set up private groups which give them privacy to discuss ideas in an environment which perceived as safer than Blackboard can provide. No staff interference, unless they choose to invite them in, and the opportunity to select who in the class can engage. The other striking finding is the difference in use between the genders. Males are using blackboard more frequently than females, whilst the reverse is true for Facebook. Interviews suggest that this may have something to do with needing to access lecture notes… Overall, though, it appears that there is little relationship between the time spent engaging with Blackboard and reports that students have learned from it. Because Blackboard is our central repository for notes, any contact is likely to result in some learning. Facebook, however, shows a clear relationship between frequency of use and perception of learning – and our students post frequently to Facebook. Whilst much of this is probably trivia and social chit chat, the educational elements of it are, de facto, contructivist in nature. Further questions need to be answered - Is the reason the students learn from Facebook because they are creating content which others will see and comment on? Is it because they can engage in a dialogue, without the risk of interruption by others?
Resumo:
A highly stereoselective synthesis of conformationally constrained cyclic γ-amino acids has been devised. The key step involves an intramolecular cyclization of a nitronate onto a conjugated ester, promoted by a bifunctional thiourea catalyst. This methodology has been successfully applied to generate a variety of γ-amino acids, including some containing three contiguous stereocenters, with very high diastereoselectivity and excellent enantioselectivity. It is postulated that an interaction that is key to the success of the process is the simultaneous coordination of the thiourea functionality to both the conjugated ester and the nitronate. Finally, the synthetic utility of these compounds is demonstrated in the synthesis of two dipeptides derived from the C- and N-termini.
Resumo:
Acrylamide and pyrazine formation, as influenced by the incorporation of different amino acids, was investigated in sealed low-moisture asparagine-glucose model systems. Added amino acids, with the exception of glycine and cysteine and at an equimolar concentration to asparagine, increased the rate of acrylamide formation. The strong correlation between the unsubstituted pyrazine and acrylamide suggests the promotion of the formation of Maillard reaction intermediates, and in particular glyoxal, as the determining mode of-action. At increased amino acid concentrations, diverse effects were observed. The initial rates of acrylamide formation remained high for valine, alanine, phenylalanine, tryptophan, glutamine, and Ieucine, while a significant mitigating effect, as evident from the acrylamide yields after 60 min of heating at 160 degrees C, was observed for proline, tryptophan, glycine, and cysteine. The secondary amine containing amino acids, proline and tryptophan, had the most profound mitigating effect on acrylamide after 60 min of heating. The relative importance of the competing effect of added amino acids for alpha-dicarbonyls and acrylamide-amino, acid alkylation reactions is discussed and accompanied by data on the relative formation rates of selected amino acid-AA adducts.
Resumo:
A new homo-proline tetrazole derivative 7 has been prepared and shown to have improved properties for achieving asymmetric Michael addition of carbonyl compounds to nitro-olefins.
Resumo:
Tetrazole and acylsulfonamide organocatalysts derived from proline have been synthesised and applied to the asymmetric Mannich, nitro-Michael and aldol reactions to give results that are superior to the proline-catalysed counterpart.