This study aimed to assess the prevalence of natural resistance-associated substitutions (RASs) to NS3, NS5A and NS5B inhibitors in 86 genotype 1 Hepatitis C Virus (HCV)-infected patients from Buenos Aires, Argentina, and to determine their effect on therapy outcome. Additionally, virological, clinical and host genetic factors were explored as predictors of the presence of baseline RASs. NS3 RASs (39.2%) were more prevalent than NS5A RASs (25%) and NS5B RASs (8.9%). In the three regions, the frequencies of RASs were significantly higher in HCV-1b than in HCV-1a. The prevalence of Y93H, L159F and Q80K were 1.3%, 6.3% and 2.5%, respectively. IFNL3 CC genotype was identified as an independent predictor of the presence of baseline RASs in NS5A and NS3 genes (p = 0.0005 and p = 0.01, respectively). Sustained virologic response was achieved by 93.3% of the patients after receiving direct-acting antivirals (DAAs), although 48.7% of them showed baseline RASs related to the DAA-regimen. Notably, the prevalence of clinically relevant RASs in the three genes was lower than that observed around the world. The baseline presence of RASs in both subtypes did not appear to affect therapy outcome. These results support the need to evaluate resistance patterns in each particular country since RASs´ prevalence significantly vary worldwide.

. Secondary students' thinking about familiar phenomena: learners' explanations from a curriculum context where 'particles' is a key idea for organising teaching and learning. International Journal of Science Education, Taylor & Francis (Routledge), 2009, 31 (14), pp.1917-1952 Secondary students' thinking about familiar phenomena: learners' explanations from a curriculum context where 'particles' is a key idea for organising teaching and learning. Abstract:Particle models of matter are widely recognised as being of fundamental importance in many branches of modern science, and particle ideas are commonly introduced and developed in the secondary school curriculum. However, research undertaken in a range of national contexts has identified significant learning difficulties in this topic, and suggests that notions of particles that match scientific models are generally only attained over periods of some years. A National Curriculum in Science was imposed in England over the period 1989-1993, and was later supplemented by increasingly prescriptive guidance to teachers. This culminated in a framework for teaching lower secondary science, which identified 'particles' as one of five key ideas for organising teaching and learning. In this curriculum context, a basic particle model is introduced at the start of secondary education, and consolidated by being revisited in various contexts over three years. The present paper reports an interview-about-events based study that explored the way English secondary students explained phenomena commonly met in school science. It was found that most students used the notion of particles in their responses, although most of their particle-based explanations reflected alternative conceptions that have been reported in previous research. It is concluded that a curriculum strategy of early introduction and regular application during the early secondary years is not sufficient to support the desired level of progression in thinking with particle concepts, and more sophisticated pedagogy is needed.

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<p>Este trabajo se suma a los múltiples esfuerzos que se han realizado en México y en el mundo para documentar las experiencias de los profesores universitarios en el abrupto cambio de educación presencial a educación remota ocasionado por la pandemia. Se presentan los resultados de una encuesta que respondieron 647 profesores de la Facultad de Química de la Universidad Nacional Autónoma de México. El cuestionario tiene 17 preguntas cerradas y 6 preguntas abiertas que fueron analizadas con estadística descriptiva y análisis de contenido. Los resultados muestran que la mayoría de los profesores vivió la situación más como un reto que como un problema. Si bien la mayoría no tenía experiencia con la docencia en línea, la enfrentaron utilizando distintos recursos. La experiencia de los docentes es muy diversa y muestra la necesidad de compartir formas de plantear las clases y recursos para transformar las prácticas de enseñanza en la universidad.</p>