University of Groningen

About: University of Groningen is a education organization based out in Groningen, Groningen, Netherlands. It is known for research contribution in the topics: Population & Poison control. The organization has 36346 authors who have published 69116 publications receiving 2940370 citations. The organization is also known as: Rijksuniversiteit Groningen & RUG.

Local-density functional and on-site correlations: The electronic structure of La2CuO4 and LaCuO3

Abstract: State-of-the-art electronic-structure calculations based on the local-density approximation (LDA) to the density functional fail to reproduce the insulating antiferromagnetic ground state in the parent compounds of the high-temperature oxide superconductors. Similar problems have been observed earlier in classical transition-metal oxides such as FeO, CoO, and NiO. In this work we present the method which delivers the correct insulating antiferromagnetic ground state in the correlated oxides preserving other properties as well as the efficiency of the standard LDA. The method embeds the relevant (for a given system of electrons) part of the Hubbard Hamiltonian into the Kohn-Sham LDA equation. The resulting Hamiltonian attempts to fix two intrinsic problems of the LDA: the deficiency in forming localized (atomiclike) moments and the lack of discontinuity of the effective one-particle potential when going from occupied to unoccupied states. We present the detailed study of La2CuO4 and LaCuO3. In the case of La2CuO4 the energy gap and the value of the localized magnetic moment in the stable insulating antiferromagnetic solution are in good agreement with experiment. We compare our results with the standard local spin density approximation calculation and multiband Hubbard model calculations, as well as with results of spectroscopy: inverse photoemission, valence photoemission, and x-ray absorption at the K edge of oxygen. In the case of LaCuO3 such an extensive comparison is limited due to the limited data available for this compound. We discuss, however, the electric and magnetic properties and the insulator-metal-insulator transitions upon increase of oxygen deficiency.

Disability and quality of life impact of mental disorders in Europe: results from the European Study of the Epidemiology of Mental Disorders (ESEMeD) project.

Abstract: Objective: This manuscript examines the impact of mental health state and specific mental and physical disorders on work role disability and quality of life in six European countries. Method: The ESEMeD study was conducted in: Belgium, France, Germany, Italy, the Netherlands and Spain. Individuals aged 18 years and over who were not institutionalized were eligible for an in-home computer-assisted interview. Common mental disorders, work loss days (WLD) in the past month and quality of life (QoL) were assessed, using the WMH-2000 version of the CIDI, the WHODAS-II, and the mental and physical component scores (MCS, PCS) of the 12-item short form, respectively. The presence of five chronic physical disorders: arthritis, heart disease, lung disease, diabetes and neurological disease was also assessed. Multivariate regression techniques were used to identify the independent association of mental and physical disorders while controlling for gender, age and Country. Results: In each country, WLD and loss of QoL increased with the number of disorders. Most mental disorders had approximately 1.0 SD-unit lower mean MCS and lost three to four times more work days, compared with people without any 12-month mental disorder. The 10 disorders with the highest independent impact on WLD were: neurological disease, panic disorder, PTSD, major depressive episode, dysthymia, specific phobia, social phobia, arthritis, agoraphobia and heart disease. The impact of mental vs. physical disorders on QoL was specific, with mental disorders impacting more on MCS and physical disorders more on PCS. Compared to physical disorders, mental disorders had generally stronger 'cross-domain' effects. Conclusion: The results suggest that mental disorders are important determinants of work role disability and quality of life, often outnumbering the impact of common chronic physical disorders.

Mendelian randomization of blood lipids for coronary heart disease

Abstract: AIMS: To investigate the causal role of high-density lipoprotein cholesterol (HDL-C) and triglycerides in coronary heart disease (CHD) using multiple instrumental variables for Mendelian randomization. METHODS AND RESULTS: We developed weighted allele scores based on single nucleotide polymorphisms (SNPs) with established associations with HDL-C, triglycerides, and low-density lipoprotein cholesterol (LDL-C). For each trait, we constructed two scores. The first was unrestricted, including all independent SNPs associated with the lipid trait identified from a prior meta-analysis (threshold P < 2 × 10(-6)); and the second a restricted score, filtered to remove any SNPs also associated with either of the other two lipid traits at P ≤ 0.01. Mendelian randomization meta-analyses were conducted in 17 studies including 62,199 participants and 12,099 CHD events. Both the unrestricted and restricted allele scores for LDL-C (42 and 19 SNPs, respectively) associated with CHD. For HDL-C, the unrestricted allele score (48 SNPs) was associated with CHD (OR: 0.53; 95% CI: 0.40, 0.70), per 1 mmol/L higher HDL-C, but neither the restricted allele score (19 SNPs; OR: 0.91; 95% CI: 0.42, 1.98) nor the unrestricted HDL-C allele score adjusted for triglycerides, LDL-C, or statin use (OR: 0.81; 95% CI: 0.44, 1.46) showed a robust association. For triglycerides, the unrestricted allele score (67 SNPs) and the restricted allele score (27 SNPs) were both associated with CHD (OR: 1.62; 95% CI: 1.24, 2.11 and 1.61; 95% CI: 1.00, 2.59, respectively) per 1-log unit increment. However, the unrestricted triglyceride score adjusted for HDL-C, LDL-C, and statin use gave an OR for CHD of 1.01 (95% CI: 0.59, 1.75). CONCLUSION: The genetic findings support a causal effect of triglycerides on CHD risk, but a causal role for HDL-C, though possible, remains less certain.

Age and work‐related motives: Results of a meta‐analysis

Abstract: Summary An updated literature review was conducted and a meta-analysis was performed to investigate the relationship between age and work-related motives. Building on theorizing in life span psychology, we hypothesized the existence of age-related differences in work-related motives. Specifically,we proposedan age-related increase in thestrengthof securityandsocial motives, and an age-related decrease in the strength of growth motives. To investigate life span developmental theory predictions about age-related differences in control strategies, we also examinedthe relationship between age and intrinsic and extrinsic motives.Consistent with our predictions, meta-analytic results showed a significant positive relationship between age and intrinsic motives, and a significant negative relationship between age and strength of growth and extrinsic motives. The predicted positive relation between age and strength of social and security motives was only found among certain subgroups. Implications of these findings for work motivation and life span theories and future research are discussed. Copyright # 2010 John Wiley & Sons, Ltd.