A research approach to designing chemistry education using authentic practices as contexts

We discuss how to reduce the incongruence between outcomes (both cognitive and affective) of conventional secondary chemistry curriculum and what is to be attained: the meaningful connection of students' learning to daily life and societal issues. This problem is addressed by a design study with one curriculum unit about 'Water Quality'. With several research cycles using developmental research, we developed an emergent understanding about an instructional framework for curriculum units that embodies a coherent 'need-to-know' principle and is based on authentic practices. Using this framework we show with some other examples how a context-based chemistry curriculum can be constructed on basis of the developed ‘need-to-know’ principle

Correcting for Selection Bias and Missing Response in Regression using Privileged Information

When estimating a regression model, we might have data where some labels are missing, or our data might be biased by a selection mechanism. When the response or selection mechanism is ignorable (i.e., independent of the response variable given the features) one can use off-the-shelf regression methods; in the nonignorable case one typically has to adjust for bias. We observe that privileged data (i.e. data that is only available during training) might render a nonignorable selection mechanism ignorable, and we refer to this scenario as Privilegedly Missing at Random (PMAR). We propose a novel imputation-based regression method, named repeated regression, that is suitable for PMAR. We also consider an importance weighted regression method, and a doubly robust combination of the two. The proposed methods are easy to implement with most popular out-of-the-box regression algorithms. We empirically assess the performance of the proposed methods with extensive simulated experiments and on a synthetically augmented real-world dataset. We conclude that repeated regression can appropriately correct for bias, and can have considerable advantage over weighted regression, especially when extrapolating to regions of the feature space where response is never observed

Euro-Collins Solution Versus Uw-Solution for Long-Term Liver Preservation in the Isolated Rat-Liver Perfusion Model

To compare UW-solution (UW) and Euro-Collins (EC) for long-term liver preservation we investigated the morphology and metabolic capacity of rat liver after 18 and 42-hours cold-storage in either UW or EC

Борис Алексеевич Нелепо (к 80-летию со дня рождения)

15 августа 2012 г. исполнилось бы 80 лет со дня рождения известного ученого-океанолога, доктора физико-математических наук, профессора, лауреата Государственной премии УССР (1979 г.) и СССР (1989 г.) в области науки и техники, директора Морского гидрофизического института АН УССР в 1974 – 1985 гг., первого главного редактора «Морского гидрофизического журнала», академика НАН Украины Бориса Алексеевича Нелепо (1932 – 2007)

Development of a new therapeutic technique to direct stem cells to the infarcted heart using targeted microbubbles: StemBells

Successful stem cell therapy after acute myocardial infarction (AMI) is hindered by lack of engraftment of sufficient stem cells at the site of injury. We designed a novel technique to overcome this problem by assembling stem cell-microbubble complexes, named 'StemBells'.StemBells were assembled through binding of dual-targeted microbubbles (~ 3 μm) to adipose-derived stem cells (ASCs) via a CD90 antibody. StemBells were targeted to the infarct area

Expectations and needs of patients with a chronic disease toward self-management and eHealth for self-management purposes

Background: Self-management is considered as an essential component of chronic care by primary care professionals. eHealth is expected to play an important role in supporting patients in their self-management. For effective implementation of eHealth it is important to investigate patients’ expectations and needs regarding self-management and eHealth. The objectives of this study are to investigate expectations and needs of people with a chronic condition regarding self-management and eHealth for self-management purposes, their willingness to use eHealth, and possible differences between patient groups regarding these topics. Methods: Five focus groups with people with diabetes (n = 14), COPD (n = 9), and a cardiovascular condition (n = 7) were conducted in this qualitative research. Separate focus groups were organized based on patients’ chronic condition. The following themes were discussed: 1) the impact of the chronic disease on patients’ daily life; 2) their opinions and needs regarding self-management; and 3) their expectations and needs regarding, and willingness to use, eHealth for self-management purposes. A conventional content analysis approach was used for coding. Results: Patient groups seem to differ in expectations and needs regarding self-management and eHealth for self-management purposes. People with diabetes reported most needs and benefits regarding self-management and were most willing to use eHealth, followed by the COPD group. People with a cardiovascular condition mentioned having fewer needs for self-management support, because their disease had little impact on their life. In all patient groups it was reported that the patient, not the care professional, should choose whether or not to use eHealth. Moreover, participants reported that eHealth should not replace, but complement personal care. Many participants reported expecting feelings of anxiety by doing measurement themselves and uncertainty about follow-up of deviant data of measurements. In addition, many participants worried about the implementation of eHealth being a consequence of budget cuts in care. Conclusion: This study suggests that aspects of eHealth, and the way in which it should be implemented, should be tailored to the patient. Patients’ expected benefits of using eHealth to support self-management and their perceived controllability over their disease seem to play an important role in patients’ willingness to use eHealth for self-management purposes

Points de vue de professeurs et de futurs professeurs de chimie concernant l'enseignement de la combustion

Prospective and experienced chemistry teachers’ views on teaching combustion : a comparative study An important task of science teachers should be to take students preconceptions and difficulties into account and to negotiate the meanings of specific science concepts. In this context, teachers’ pedagogical content knowledge plays an important role. This paper presents a study of prospective and in-service chemistiy teachers’ conceptions of how to teach the concept of combustion. Seven prospective teachers and seven experienced teachers were invited to prepare a first lesson about combustion for students aged 14-15. Research data were obtained from audiotaped semi-structured interviews with the teachers. Besides, their written lesson plans as well as their answers on an accompanying questionnaire were collected and analysed. The results reveal a number of important characteristics of teachers’ views on teaching combustion. Interesting differences between views of prospective and experienced teachers have also been found. Implications of the study for science teacher education are presented.Une des tâches importantes des professeurs de sciences devrait être de prendre en compte les (pré) conceptions et les difficultés des élèves ainsi que de négocier les significations de concepts scientifiques bien spécifiques. Dans ce contexte, la connaissance du contenu pédagogique chez les enseignants joue un rôle important. Cet article présente une étude des points de vue qu’ont les futurs enseignants de chimie sur la manière d’enseigner le concept de la combustion. Sept futurs enseignants et sept professeurs confirmés ont été invités à préparer un premier cours sur la combustion (pour des élèves de 14-15 ans). Les entretiens enregistrés de façon semi-informelle avec les enseignants, la rédaction de leurs projets de séance ainsi que leurs réponses à un questionnaire joint constituent les données recueillies. Les résultats révèlent nombre de caractéristiques importantes des points de vue de ces professeurs sur l’enseignement de la combustion. On a également trouvé des différences intéressantes entre les points de vue des futurs enseignants et ceux des professeurs confirmés. On présentera ici les implications de cette étude concernant la formation des professeurs de sciences.Puntos de vista de profesores y futuros profesores de química relacionados con la enseñanza de la combustión Una de las tareas importantes de los profesores de ciencias debería ser la toma en cuenta de las (pre) concepciones y las dificultades de los alumnos, así como las significaciones de los conceptos científicos bien específicos. En este contexto, el conocimiento del contenido pedagógico de los enseñantes juega un papel importante. Este artículo presenta un estudio de los puntos de vista que tienen los futuros docentes de química sobre la manera de enseñar el concepto de combustión. Siete futuros profesores y siete profesores confirmados han sido invitados a preparar un primer curso sobre la combustión (para los alumnos de 14-15 años). Las entrevistas enregistradas de manera poco formal con los docentes, la redacción de sus proyectos de la secuencia así que las respuestas a un cuestionario conjunto, constituyen los datos recogidos. Los resultados muestran un número importante de puntos de vista de esos profesores sobre la enseñanza de la combustión. Encontramos también, diferencias interesantes entre los puntos de vista de los futuros profesores y aquellos de los profesores confirmados. Presentamos aquí las implicaciones de este estudio referente la formación de los profesores de ciencias.Jong Onno de. Points de vue de professeurs et de futurs professeurs de chimie concernant l'enseignement de la combustion. In: Aster, recherches en didactique des sciences expérimentales, n°26, 1998. L'enseignement scientifique vu par les enseignants. pp. 183-205

Enseñanza de las ciencias : revista de investigación y experiencias didácticas

Resumen basado en el de la publicaciónResumen en inglésLa importancia de los experimentos en el aula en los currículos escolares de ciencias está generalmente aceptada. Sin embargo, hay una amplia variedad de dificultades en la enseñanza de laboratorio, así como dificultades para aprender de las experiencias prácticas. Se considera el trabajo de laboratorio en la ciencia de la escuela secundaria desde una perspectiva «constructivista». Desde esta perspectiva, se describe un tipo particular de experimento de ciencias escolares, el denominado experimento de presentación de problemas. Se informa también de las experiencias de los profesores de química en estos experimentos. Finalmente se discuten varios dilemas (y resoluciones) en el uso de experimentos de presentación de problemas.ES