612 research outputs found
Integrating the Constructionist Learning Theory with Computational Thinking Classroom Activities
In computer science education at school, computational thinking has been an emerging topic over the last decade. Even though, computational thinking is interpreted and integrated in classrooms in different ways, an identification process about what computational thinking is about has been in progress among computer science school-teachers and computer science education researchers since Wing’s initial paper on the characteristics of computational thinking. On the other hand, the constructionist learning theory by Papert, based on constructivism and Piaget, has a long tradition in computer science education for describing the students’ learning process by hands-on activities. Our contribution, in this paper, is to present a new mapping tool which can be used to review classroom activities in terms of both computational thinking and constructionist learning. For the tool, we have reused existing definitions of computer science concepts and computational thinking concepts and combined these with our new constructionism matrix. The matrix’s most notable feature is its scale of learners’ autonomy. This scale represents the degree of choices learners have at each stage of development of their artefact. To develop the scale definitions, we trialed the mapping tool, coding twenty-one popular international computing activities for pupils aged 5 to 11 (K-5). From our trial, we have shown that we can use the mapping tool, with a moderate to high degree of reliability across coders, to analyse classroom activities with regard to computational thinking and constructionism, however, further validation is needed to establish its usefulness. Despite a small number of activities (n = 21) being analysed with our mapping tool, our preliminary results showed several interesting findings. Firstly, that learner autonomy was low for defining the problem and developing their own design. Secondly that the activity type (such as lesson plan rather than online activity) or artefact created (such as physical artefact rather than onscreen activity or unplugged activity), rather than the computational thinking or computer science concept being taught was related to learner autonomy. This provides some tentative evidence, which may seem obvious, that the learning context rather than the earning content is related to degree of constructionism of an activity and that computational thinking per se may not be related to constructionism. However, further work is needed on a larger number of activities to verify andvalidate this suggestion
A twenty-first century perspective on concepts of modern epidemiology in Ignaz Philipp Semmelweis’ work on puerperal sepsis
We aimed to review Semmelweis’s complete work on puerperal sepsis mortality in maternity wards in relation to exposure to cadavers and chlorine handwashing and other factors from the perspective of modern epidemiological methods. We reviewed Semmelweis' complete work and data as published by von Györy 1905 according to current standards. We paid particular attention to Semmelweis's definition of mortality in and of itself, to concepts of modern epidemiology that were already recognizable in Semmelweis's work, and to bias sources. We did several quantitative bias analyses to address selection bias and information bias from outcome measurement error. Semmelweis addressed biases that have become known to modern epidemiology, such as confounding, selection bias and bias from outcome misclassification. Our bias analysis shows that differential loss to follow-up is an unlikely explanation for his results. Bias due to outcome misclassification would only be relevant if misclassification differed between time periods. Confounding by health status was likely but could not be quantitatively addressed. Semmelweis was aware that cause-specific mortality is a function of incidence and prognosis. He reasoned in potential outcome terms to estimate the reduced number of deaths from an intervention. He advanced a hypothesis of clinic overcrowding as a risk factor for puerperal sepsis mortality that turns out to be wrong. Semmelweis’ data provide a great pool for illustrating the logic of scientific discovery by use of the numerical method. The explanatory power of his work was strong and Semmelweis was able to refute several previous causal explanations
Lifetime prevalence and determinants of hand eczema in an adolescent population in Germany: 15-year follow-up of the LISA cohort study
Background Hand eczema is a common inflammatory skin disorder in both adolescence and adulthood. Objectives We sought to assess the lifetime prevalence of hand eczema and associated exogenous and endogenous risk factors among adolescents in Germany. Methods This was a cross-sectional study embedded into a prospective population-based birth cohort in four regions of Germany, which recruited healthy neonates born between November 1997 and January 1999. We included 1736 participants who had completed the 15-year follow-up from birth cohort and 84.6% (1468/1736) had clearly reported whether they have ever had hand eczema. All the data were based on questionnaires and blood tests (immunoglobulin E). Multivariable logistic regression analysis was used to examine endogenous and exogenous factors in relation to the lifetime prevalence of hand eczema among adolescents. Results One thousand four hundred and sixty-eight adolescents (715 girls, 48.7%) were included in the final analysis. The lifetime prevalence of hand eczema among adolescents at the age of 15 was 10.4% (95% confidence interval [CI]: 8.9%-12.1%), with a significantly higher lifetime prevalence among girls than boys (12.7% vs. 8.2%, P = 0.005). Multivariable logistic regression analysis indicated statistically significant associations between the lifetime prevalence of hand eczema and having ever been diagnosed with atopic dermatitis (aOR = 1.8, 95% CI: 1.1-2.8) or having ever had dry skin (aOR = 1.9, 95% CI: 1.1-3.1), respectively. No statistically significant independent associations were found between asthma, hay fever, allergy-related clinical symptoms, immunoglobulin E positivity and other exogenous factors in relation to hand eczema. Conclusion Our study fills a research gap on the epidemiological burden of hand eczema among adolescents. One out of ten ever suffered from hand eczema until age 15 years indicating that hand eczema constitutes a significant burden in paediatric populations. The role of atopic dermatitis in hand eczema reinforces previous findings. Exogenous risk factors warrant further investigation
Neighbourhood greenness and income of occupants in four German areas: GINIplus and LISAplus
Objective We investigated whether families with lower individual-level socioeconomic status (SES) reside in less green neighbourhoods in four areas in Germany. Methods Data were collected within two German birth cohorts – GINIplus and LISAplus. Net equivalent household income was categorized into study area-specific tertiles and used as a proxy for individual-level SES. Neighbourhood greenness was calculated in 500-m buffers around home addresses as: 1) the mean normalized difference vegetation index (NDVI); 2) percent tree cover. Associations between income and neighbourhood greenness were assessed per study area using adjusted linear regression models. Results In the Munich and Leipzig areas, families in the low and medium income tertiles resided in neighbourhoods with lower NDVI compared to those in the high income tertile (mean percent change in NDVI: −4.0 (95% confidence interval = −6.7 to −1.3) and −5.5 (−10.9 to −0.2), respectively). In contrast, in the Wesel area, families in the low income tertile resided in neighbourhoods with higher NDVI (2.9 (0.5–5.3)). Only the association in the Munich area was replicated when using tree cover instead of the NDVI. Conclusions This study provides suggestive evidence that the presence and direction of associations between greenness and SES is region-specific in Germany. The degree of urbanization did not clarify this heterogeneity completely
Contact frequency determines outcome of basal insulin initiation trials in type 2 diabetes
Aims/hypothesis The aim of the present study was to investigate whether predetermined contact frequency with the study teamand endpoint insulin dose are associated with study outcomes in basal insulin initiation trials in type 2 diabetes. Methods A systematic Medline search was performed. Using data from the selected studies, contact frequency was plotted against HbA(1c) reduction and endpoint insulin dose. The importance of face-to-face vs telephone contact was also analysed. Insulin dose was plotted against HbA(1c) reduction, hypoglycaemia rate and weight gain. To investigate non-specific study effects, the relationship between contact frequency and HbA(1c) was also assessed in dipeptidyl peptidase-4 (DPP-4) inhibitor trials. Results The reduction in HbA(1c) was highly correlated with contact frequency and endpoint insulin dose (r(2)=0.751, p<0.001 and r(2)=0.433, p=0.008, respectively). However, after adjusting for contact frequency, the relationship between insulin dose and HbA(1c) reduction was no longer significant (p=0.270). The frequency of both clinical and telephone contacts were independent predictors of HbA(1c) improvement (p=0.010 and p<0.001, respectively). We found no dose response relationship between end-of-study insulin dose and hypoglycaemia or weight gain. In DPP-4 inhibitor studies, contact frequency was not positively associated with HbA(1c). Conclusions/interpretation The frequency of contact with the study team is highly correlated with the improvement in HbA(1c) achieved in basal insulin initiation trials in type 2 diabetic patients. This has important implications for trial design and interpretation, as well as for clinical car
Residential greenness is differentially associated with childhood allergic rhinitis and aeroallergen sensitization in seven birth cohorts
Background The prevalence of allergic rhinitis is high, but the role of environmental factors remains unclear. We examined cohort‐specific and combined associations of residential greenness with allergic rhinitis and aeroallergen sensitization based on individual data from Swedish (BAMSE), Australian (MACS), Dutch (PIAMA), Canadian (CAPPS and SAGE), and German (GINIplus and LISAplus) birth cohorts (n = 13 016). Methods Allergic rhinitis (doctor diagnosis/symptoms) and aeroallergen sensitization were assessed in children aged 6–8 years in six cohorts and 10–12 years in five cohorts. Residential greenness was defined as the mean Normalized Difference Vegetation Index (NDVI) in a 500‐m buffer around the home address at the time of health assessment. Cohort‐specific associations per 0.2 unit increase in NDVI were assessed using logistic regression models and combined in a random‐effects meta‐analysis. Results Greenness in a 500‐m buffer was positively associated with allergic rhinitis at 6–8 years in BAMSE (odds ratio = 1.42, 95% confidence interval [1.13, 1.79]) and GINI/LISA South (1.69 [1.19, 2.41]) but inversely associated in GINI/LISA North (0.61 [0.36, 1.01]) and PIAMA (0.67 [0.47, 0.95]). Effect estimates in CAPPS and SAGE were also conflicting but not significant (0.63 [0.32, 1.24] and 1.31 [0.81, 2.12], respectively). All meta‐analyses were nonsignificant. Results were similar for aeroallergen sensitization at 6–8 years and both outcomes at 10–12 years. Stratification by NO2 concentrations, population density, an urban vs rural marker, and moving did not reveal consistent trends within subgroups. Conclusion Although residential greenness appears to be associated with childhood allergic rhinitis and aeroallergen sensitization, the effect direction varies by location
Differential effects of lung inflammation on insulin resistance in humans and mice
BACKGROUND: The rates of obesity, its associated diseases, and allergies are raising at alarming rates in most countries. House dust mites (HDM) are highly allergenic and exposure often associates with an urban sedentary indoor lifestyle, also resulting in obesity. The aim of this study was to investigate the epidemiological association and physiological impact of lung inflammation on obesity and glucose homeostasis. METHODS: Epidemiological data from 2207 adults of the population-based KORA FF4 cohort were used to test associations between asthma and rhinitis with metrics of body weight and insulin sensitivity. To obtain functional insights, C57BL/6J mice were intranasally sensitized and challenged with HDM and simultaneously fed with either low-fat or high-fat diet for 12 weeks followed by a detailed metabolic and biochemical phenotyping of the lung, liver, and adipose tissues. RESULTS: We found a direct association of asthma with insulin resistance but not body weight in humans. In mice, co-development of obesity and HDM-induced lung inflammation attenuated inflammation in lung and perigonadal fat, with little impact on body weight, but small shifts in the composition of gut microbiota. Exposure to HDM improved glucose tolerance, reduced hepatosteatosis, and increased energy expenditure and basal metabolic rate. These effects associate with increased activity of thermogenic adipose tissues independent of uncoupling protein 1. CONCLUSIONS: Asthma associates with insulin resistance in humans, but HDM challenge results in opposing effects on glucose homeostasis in mice due to increased energy expenditure, reduced adipose inflammation, and hepatosteatosis
Genome-wide association and HLA fine-mapping studies identify risk loci and genetic pathways underlying allergic rhinitis
Allergic rhinitis is the most common clinical presentation of allergy, affecting 400 million people worldwide, with increasing incidence in westernized countries1,2. To elucidate the genetic architecture and understand the underlying disease mechanisms, we carried out a meta-analysis of allergic rhinitis in 59,762 cases and 152,358 controls of European ancestry and identified a total of 41 risk loci for allergic rhinitis, including 20 loci not previously associated with allergic rhinitis, which were confirmed in a replication phase of 60,720 cases and 618,527 controls. Functional annotation implicated genes involved in various immune pathways, and fine mapping of the HLA region suggested amino acid variants important for antigen binding. We further performed genome-wide association study (GWAS) analyses of allergic sensitization against inhalant allergens and nonallergic rhinitis, which suggested shared genetic mechanisms across rhinitis-related traits. Future studies of the identified loci and genes might identify novel targets for treatment and prevention of allergic rhinitis
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