| 1. |
- Locke, Adam E, et al.
(författare)
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Genetic studies of body mass index yield new insights for obesity biology.
- 2015
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 518:7538, s. 197-401
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Tidskriftsartikel (refereegranskat)abstract
- Obesity is heritable and predisposes to many diseases. To understand the genetic basis of obesity better, here we conduct a genome-wide association study and Metabochip meta-analysis of body mass index (BMI), a measure commonly used to define obesity and assess adiposity, in up to 339,224 individuals. This analysis identifies 97 BMI-associated loci (P < 5 × 10(-8)), 56 of which are novel. Five loci demonstrate clear evidence of several independent association signals, and many loci have significant effects on other metabolic phenotypes. The 97 loci account for ∼2.7% of BMI variation, and genome-wide estimates suggest that common variation accounts for >20% of BMI variation. Pathway analyses provide strong support for a role of the central nervous system in obesity susceptibility and implicate new genes and pathways, including those related to synaptic function, glutamate signalling, insulin secretion/action, energy metabolism, lipid biology and adipogenesis.
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| 2. |
- Shungin, Dmitry, et al.
(författare)
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New genetic loci link adipose and insulin biology to body fat distribution.
- 2015
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 518:7538, s. 187-378
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Tidskriftsartikel (refereegranskat)abstract
- Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms.
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| 3. |
- Alatalo, Tarja, 1961-, et al.
(författare)
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Characteristics of Teacher Competence : Trends over Time and Between Student Groups in the Swedish Compulsory School
- 2018
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Konferensbidrag (refereegranskat)abstract
- BackgroundAchievement differences across schools have increased in Sweden during the past two decades, at the same time as average achievement levels have declined, for example in mathematics (Holmlund et al., 2014; SOU 2014:05) and reading (Skolverket, 2013). These negative trends may be related to schools’ demographic, organizational and resource prerequisites. The organizational basis for the Swedish compulsory school has undergone significant changes since the late 1980s, with free school choice, an increasing number of private schools and a larger autonomy for school leaders. The increased school segregation with respect to migration background since the implementation of these reforms (Yang Hansen & Gustafsson, 2016), could possibly be caused by the continuing decline in inclusion of migrant students and a related educational inequality in instructional quality and teacher competence. Inclusion is defined as a structure of organizing integration according to particular rules and regulations.The results of research on effects of teacher competence are, however, somewhat fragmented and unclear, at least with respect to effects on different student groups. This can partly be explained by uncertainties in the determination of crucial teacher characteristics. Making comparisons between for example authorized and unauthorized teachers has been shown to be problematic. There is vast research in this field which is characterized by severe methodological problems, e.g. with respect to drawing causal conclusions from cross-sectional observational data. For example, no correlation between student achievement and various resource factors has been found in some studies (e.g. Hanushek, 1997), whereas others found a positive correlation (e.g. Greenwald, Hedges & Laine, 1996).A teacher effect on student achievement is, however, well manifested (e.g., Gustafsson, 2003; Gustafsson & Myrberg, 2002; Johansson, Myrberg, & Rosén, 2015; Nye, Konstantopoulus, & Hedges, 2004; Rockoff, 2004), and the results also suggest that lower achieving students, as for example immigrants, are the more likely to benefit from increases in teacher effectiveness (e.g., Sanders, 1998). Teacher quality is, furthermore, one of the resource factors that explains most of the increase in performance differences between schools in Sweden (Björklund, Fredriksson, Gustafsson, & Öckert, 2010, Ch 7; Gustafsson & Myrberg, 2002). The general reduction in teacher quality in Sweden the last decades (SOU 2014:05), and the decreased equality of allocation of teacher competence between schools (Hansson & Gustafsson, 2016; OECD, 2013), supports these results. However, the variation between student outcomes that different teachers are achieving (Hanushek, 2003) needs to be further problematized and discussed. Teacher knowledge and skills, teacher training and teaching experience are examples of characteristics highlighted in different meta-studies (e.g., Greenwald, Hedges & Laine, 1996), that should be subject of such an investigation.This study intends to develop a precise and differentiated description of teacher quality for use in future analyses of relations between teacher competence and educational results, with focus on interactions with student composition of schools due to students’ socio-economic and migration backgrounds. The description is among other factors focusing on teacher’s basic knowledge, subject-related and pedagogical training, and type of teacher training program. One aim is to investigate the variation over time in access to qualified teachers and the variation in teacher qualifications between schools. In further analyses, the significance of the teacher characteristics for literacy and mathematics in grades 1 to 6 will be focused.Overall, the project, which this study is a part of, is expected to generate insights about essential conditions for effective and equitable teaching in Swedish and mathematics in primary school, and about distributions of teacher competence across schools with different student composition.
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