Teachers’ Beliefs About Knowledge of Teaching and Their Impact on Teaching Practices: The Role of Beliefs in the Classroom

This study investigated secondary school mathematics teachers’ beliefs about knowledge of teaching and its impact on their teaching practices. Two teachers participated in the study. Data were collected through an interview and classroom observations. The results indicated that the teachers’ beliefs about the goal of mathematics education and about the importance of teachers’ understanding the way students think about certain mathematics subjects had impact on their teaching practices. However, the teachers’ teaching practices were also affected by the students

Burden of non-communicable diseases among adolescents aged 10–24 years in the EU, 1990–2019: a systematic analysis of the Global Burden of Diseases Study 2019

Background Disability and mortality burden of non-communicable diseases (NCDs) have risen worldwide; however, the NCD burden among adolescents remains poorly described in the EU. Methods Estimates were retrieved from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. Causes of NCDs were analysed at three different levels of the GBD 2019 hierarchy, for which mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) were extracted. Estimates, with the 95% uncertainty intervals (UI), were retrieved for EU Member States from 1990 to 2019, three age subgroups (10–14 years, 15–19 years, and 20–24 years), and by sex. Spearman's correlation was conducted between DALY rates for NCDs and the Socio-demographic Index (SDI) of each EU Member State. Findings In 2019, NCDs accounted for 86·4% (95% uncertainty interval 83·5–88·8) of all YLDs and 38·8% (37·4–39·8) of total deaths in adolescents aged 10–24 years. For NCDs in this age group, neoplasms were the leading causes of both mortality (4·01 [95% uncertainty interval 3·62–4·25] per 100 000 population) and YLLs (281·78 [254·25–298·92] per 100 000 population), whereas mental disorders were the leading cause for YLDs (2039·36 [1432·56–2773·47] per 100 000 population) and DALYs (2040·59 [1433·96–2774·62] per 100 000 population) in all EU Member States, and in all studied age groups. In 2019, among adolescents aged 10–24 years, males had a higher mortality rate per 100 000 population due to NCDs than females (11·66 [11·04–12·28] vs 7·89 [7·53–8·23]), whereas females presented a higher DALY rate per 100 000 population due to NCDs (8003·25 [5812·78–10 701·59] vs 6083·91 [4576·63–7857·92]). From 1990 to 2019, mortality rate due to NCDs in adolescents aged 10–24 years substantially decreased (–40·41% [–43·00 to –37·61), and also the YLL rate considerably decreased (–40·56% [–43·16 to –37·74]), except for mental disorders (which increased by 32·18% [1·67 to 66·49]), whereas the YLD rate increased slightly (1·44% [0·09 to 2·79]). Positive correlations were observed between DALY rates and SDIs for substance use disorders (rs=0·58, p=0·0012) and skin and subcutaneous diseases (rs=0·45, p=0·017), whereas negative correlations were found between DALY rates and SDIs for cardiovascular diseases (rs=–0·46, p=0·015), neoplasms (rs=–0·57, p=0·0015), and sense organ diseases (rs=–0·61, p=0·0005). Interpretation NCD-related mortality has substantially declined among adolescents in the EU between 1990 and 2019, but the rising trend of YLL attributed to mental disorders and their YLD burden are concerning. Differences by sex, age group, and across EU Member States highlight the importance of preventive interventions and scaling up adolescent-responsive health-care systems, which should prioritise specific needs by sex, age, and location. Funding Bill & Melinda Gates Foundation

Epistemic dimensions of students’ mathematics-related belief systems

Over the years, research on students’ epistemological beliefs has resulted in a growing common understanding but there are still some major points of discussion. Especially, the lack of consensus on the context-general and/or context-specific nature of epistemological beliefs deserves our attention. We argue that research in the field today is mainly characterized by a top-down approach that investigates students’ domain-specific beliefs from a general epistemological perspective. Alternatively, we report on one of our studies as well as some other research that takes a bottom-up approach starting from students’ domain-specific belief systems and analyzing their epistemic dimensions. Results of these studies point to the highly domain-specific nature of students’ beliefs about knowledge and knowing. Therefore, a conceptual distinction between students’ general epistemological beliefs and the epistemic dimensions of domain-related belief systems is recommended as a more appropriate way to address the context-general–context-specific discussion on epistemological beliefs.01status: publishe

Students’ emotions: A key component of self-regulated learning?

Originally, self-regulation was almost exclusively perceived as the regulation of cognitive processes resulting in an emphasis on higher order information processing and metacognition. Motivational and affective factors were considered minor components in explaining students' learning behavior and results. Although the conception of (self-regulated) learning and competence has broadened over the years to include conative and affective components next to cognitive ones, the research field is still struggling to come to a balanced understanding of the nature and role of these different components. Traditionally, the role of specific affective variables (emotions, feelings, moods) in school learning has been hardly studied, with the exception of anxiety. In the last 15 years, however, several scholars from all over the world have reported research that analyzes the role of emotions and feelings in school and academic contexts. This chapter presents a research program to investigate the role of emotions in students' (self-regulated) learning in the mathematics classroom. The chapter discusses how the integration of a socio-constructivist perspective on (mathematics) learning and a component systems approach of emotions provides a comprehensive theoretical framework for the study of the role of emotions in the mathematics classroom. © 2007 Copyright © 2007 Elsevier Inc. All rights reserved.05status: publishe

Creencias de los estudiante de matematicas. La influencia del contexto de clase [Belief systems of students of mathematics: Classroom context influences]

03status: publishe

Primary blast wave protection in combat helmet design: A historical comparison between present day and World War I.

Since World War I, helmets have been used to protect the head in warfare, designed primarily for protection against artillery shrapnel. More recently, helmet requirements have included ballistic and blunt trauma protection, but neurotrauma from primary blast has never been a key concern in helmet design. Only in recent years has the threat of direct blast wave impingement on the head-separate from penetrating trauma-been appreciated. This study compares the blast protective effect of historical (World War I) and current combat helmets, against each other and 'no helmet' or bare head, for realistic shock wave impingement on the helmet crown. Helmets included World War I variants from the United Kingdom/United States (Brodie), France (Adrian), Germany (Stahlhelm), and a current United States combat variant (Advanced Combat Helmet). Helmets were mounted on a dummy head and neck and aligned along the crown of the head with a cylindrical shock tube to simulate an overhead blast. Primary blast waves of different magnitudes were generated based on estimated blast conditions from historical shells. Peak reflected overpressure at the open end of the blast tube was compared to peak overpressure measured at several head locations. All helmets provided significant pressure attenuation compared to the no helmet case. The modern variant did not provide more pressure attenuation than the historical helmets, and some historical helmets performed better at certain measurement locations. The study demonstrates that both historical and current helmets have some primary blast protective capabilities, and that simple design features may improve these capabilities for future helmet systems