Abstract A study of macro and microfacies, palynoflora and palynofacies of the non-marine Cerro Negro Formation at President Head Peninsula, Snow Island, northwest of the Antarctic Peninsula, was developed. Two assemblages were recognized: Palynofacies assemblage 1 (P1) at the base of the section with a dominance of fern spores and conifer pollen grains, and facies association consisting of a clastic layer, with the predominance of mudstones; and Palynofacies assemblage 2 (P2) at the top of the section, with remarkable abundance of AOM/Pseudoamorphous particles, associated with facies that includes tuffs. The complete section shows in some levels the presence of freshwater algae and translucent phytoclasts. The integrated data characterizes a fluvial-lacustrine environment, what is reinforced by the occurrence of freshwater algae (Botryococcus) in some levels of P1 and P2. We could verify an increase in volcanic activity towards the top of the section that apparently has played an important role in the collapse of the palynoflora. The occurrence of the spore species Muricingulisporis annulatus, Sotasporites elegans, S. triangularis, Foraminisporis wonthaggiensis, and F. asymmetricus in the Cerro Negro Formation allows the correlation with sections in South America and Australia, suggesting an Aptian age for these deposits.

Introducción: Los accidentes de tránsito ocasionados por conductores que se encuentran bajo el efecto del alcohol constituyen una de las principales causas de accidentalidad y mortalidad vial. Ante este problema, surge la necesidad de definir límites en cuanto al nivel de alcoholemia a partir del cual se pone en riesgo el estado de vigilia necesaria para la conducción. Objetivos: Determinar las concentraciones mínimas de alcohol en sangre con las que se altera el estado de vigilia o se genera algún grado de somnolencia que pone en riesgo la habilidad y la destreza al conducir. Métodos: Metanálisis de la literatura sobre los artículos publicados entre 1999 y 2009 que evaluaron la conducción en simuladores después de la ingesta de diferentes grados de alcohol y en los que se midió la somnolencia que estos grados producen en los conductores. Resultados: Se produce mayor somnolencia en los conductores que están bajo efecto de alcohol. Las diferencias medias estandarizadas (SMD) fueron de 0,81 (IC 95%: 0,54-1,09) para personas con niveles de concentraciones de alcohol en sangre (BAC) menores a 0,05 y de SMD = 1,16 (IC 95 %: 0,93-1,4) para las personas con niveles de BAC mayores a 0,05. En todas las escalas utilizadas para medir somnolencia se corroboró el efecto del alcohol. Conclusiones: En todos los desenlaces se evidenció que, independientemente de la cantidad de alcohol en la sangre (niveles mayores y menores de BAC = 0,05), la ingesta de alcohol está asociada con mayor somnolencia.

Introduction: Traffic accidents caused by drivers under the influence of alcohol are a major cause of road accidents and mortality. Faced with this problem, defining the limit of alcohol levels from which wakefulness for the purpose of driving is jeopardized is critical. Objectives: To determine the minimum concentration of alcohol in blood that alters wakefulness or generates some degree of drowsiness that compromises driving ability and skill. Method: Meta-analysis. Systematic review of eight databases, limited to publications between 1999 and 2009 in which the assessment was made through simulators and blood alcohol concentrations were measured. Results: In all the subgroups studied it was clear that people with some intake of alcohol tend to have some degree of drowsiness compared with those with a blood alcohol level of 0. Standardized mean differences in sleepiness were high. This means there was a great difference between those with blood alcohol concentrations and those without. Conclusions: In all outcomes it was evident that regardless of the amount of alcohol in blood, alcohol intake provoked in the drivers a tendency towards sleepiness. We observed that most simulator studies tend to favor zero alcohol intake while driving because of the high degree of drowsiness that occurs.

Introducción: Existen algunos factores que aumentan el riesgo de aparición del síndrome de agotamiento profesional (SAP), como ejercer el trabajo en condiciones de violencia. Objetivo: Conocer la influencia de la violencia y de las pandillas en el quehacer docente y la apreciación de los profesores sobre la calidad de la educación. Método: Un estudio cualitativo y cuantitativo en 3 sedes de un colegio sometido a actos violentos por parte de pandillas. Se presentan los datos cualitativos que se derivan de 5 entrevistas en profundidad con informantes clave y 9 grupos focales (GF) con 114 docentes de 137 (83,2%). Resultados: Se describe la situación de violencia por pandillas. Se evidencian en los docentes situaciones de miedo, angustia o temor; desconcierto e incertidumbre; inseguridad y desconfianza; frustración, impotencia y desesperanza; tristeza y otras emociones derivadas de la situación. Se encontró disminución rendimiento docente-estudiante; poca autoridad y ruptura de límite; libertades limitadas; influencia en la salud mental y en lo emocional del docente, entre otras. Los docentes sugieren dar mayor apoyo para actividades lúdicas, deportivas y espirituales; implementar nuevos métodos o estrategias pedagógicos; leyes en defensa de profesores e incentivos para éstos, entre otros. Conclusiones: La situación de violencia por pandillas afecta a la comunidad entera y por este motivo, también ejerce efectos sobre la relación profesor-estudiante y sobre la calidad de la educación. Por tanto, se requieren medidas orientadas a mejorar la comunicación entre los diferentes actores, y a proteger la labor educativa que estos profesionales llevan a cabo.

Introduction: There are related factors that increase the risk of presenting burnout syndrome, such as working in violent conditions. Objectives: To study the influence that violence in the community and gangs has on teaching on a daily basis, as well as the teachers' opinion on the quality of education. Methods: We conducted a qualitative study in three locations of a school subject to violent acts by gangs. The qualitative data came from five deep interviews with key informants and nine focal groups with 114 of the 137 teachers (83.2%). Results: The deep interviews describe the violent situation that gangs generate in the sector. We found that teachers experience: Fear and anguish, uncertainty, lack of security and distrust, frustration and impotence, sadness, and other emotions derived from the situation. In the second question the i ndings where: Lower student-teacher performance, no boundaries and little authority, limited freedom, consequences on the mental and emotional health of the teacher, among others. The teachers suggest more support for spiritual activities, sports, arts and ieldtrips; implementation of new methods and strategies for teaching; laws to protect the teacher and incentives for them, among others. Conclusions: The violence generated by the gangs affects the entire community, indirectly affecting the teacher-student relationship, and therefore the quality of education. This problem requires immediate actions to improve communication among the different parties implicated in the problem, and measures to protect the educational tasks undertaken by the teachers.