Optimization of a charge-state analyzer for ECRIS beams

A detailed experimental and simulation study of the extraction of a 24 keV He-ion beam from an ECR ion source and the subsequent beam transport through an analyzing magnet is presented. We find that such a slow ion beam is very sensitive to space-charge forces, but also that the neutralization of the beam's space charge by secondary electrons is virtually complete for beam currents up to at least 0.5 mA. The beam emittance directly behind the extraction system is 65 pi mm mrad and is determined by the fact that the ion beam is extracted in the strong magnetic fringe field of the ion source. The relatively large emittance of the beam and its non-paraxiality lead, in combination with a relatively small magnet gap, to significant beam losses and a five-fold increase of the effective beam emittance during its transport through the analyzing magnet. The calculated beam profile and phase-space distributions in the image plane of the analyzing magnet agree well with measurements. The kinematic and magnet aberrations have been studied using the calculated second-order transfer map of the analyzing magnet, with which we can reproduce the phase-space distributions of the ion beam behind the analyzing magnet. Using the transfer map and trajectory calculations we have worked out an aberration compensation scheme based on the addition of compensating hexapole components to the main dipole field by modifying the shape of the poles. The simulations predict that by compensating the kinematic and geometric aberrations in this way and enlarging the pole gap the overall beam transport efficiency can be increased from 16 to 45%

No evidence for association between late pregnancy maternal cortisol and gray matter volume in a healthy community sample of young adolescents

A compelling amount of animal and human research has shown that perceived maternal stress during pregnancy can affect the neurodevelopment of the offspring. Prenatal maternal cortisol is frequently proposed as the biological key mechanism underlying this link; however, literature that investigates the effects of prenatal cortisol on subsequent neurodevelopment in humans is scarce. By using longitudinal data from a relatively large community sample of mother-child dyads (N = 73), this pre-registered study prospectively examined the role of maternal prenatal cortisol concentrations on subsequent individual differences in gray matter volume (GMV) and hippocampal subfield volumes at the onset of puberty of the offspring (12 years of age). Two markers of cortisol, that is, evening cortisol and circadian decline over the day, were used as indicators of maternal physiological stress during the last trimester of pregnancy. The results indicate that prenatal maternal cortisol levels were not associated with GMV or hippocampal subfield volumes of the children. These findings suggest that late pregnancy maternal cortisol may not be related to the structural development of the offspring’s brain, at least not in healthy community samples and at the onset of puberty. When examining the influence of prenatal stress on offspring neurodevelopment, future investigations should delineate gestational timing effects of the cortisol exposure, cortisol assessment method, and impact of additional biomarkers, as these were not investigated in this study

Identity experiences of black people in the Netherlands

Abstract: In this study, we used the tri-dimensional model of identity and acculturation strategies to explore how black people living in the Netherlands define themselves We used a qualitative survey design in which 14 participants (females = 8; age range 21 to 58) completed open-ended questions about their experiences of being black in the Netherlands Data was analysed using hermeneutic phenomenology in three steps: naive understanding, structural analysis, and comprehensive understanding We derived several main themes: Acceptance; Inclusion; Stereotypes; Social membership; Personspecific characteristics; Separation (Contributors); and Social Status We associated the themes Acceptance, Inclusion, and Separation (Contributors) with acculturation and acculturative strategies The other themes can be connected to the tri-dimensional identity model Social membership and Social status are related to the social and relational aspects of identity, while Person-specific characteristics can be linked to personal identity Lastly, the theme Stereotypes can be related to both acculturation and racism, but also personal identity as it shows how the participants perceive their self-concept to contradict the beliefs that mainstream Dutch society holds about them We conclude that identity construction among the black respondents was reliant on both their ethnic community membership and their membership of the mainstream Dutch community

Gender Differences in Developing Biomarker-Based Major Depressive Disorder Diagnostics

The identification of biomarkers associated with major depressive disorder (MDD) holds great promise to develop an objective laboratory test. However, current biomarkers lack discriminative power due to the complex biological background, and not much is known about the influence of potential modifiers such as gender. We first performed a cross-sectional study on the discriminative power of biomarkers for MDD by investigating gender differences in biomarker levels. Out of 28 biomarkers, 21 biomarkers were significantly different between genders. Second, a novel statistical approach was applied to investigate the effect of gender on MDD disease classification using a panel of biomarkers. Eleven biomarkers were identified in men and eight in women, three of which were active in both genders. Gender stratification caused a (non-significant) increase of Area Under Curve (AUC) for men (AUC=0.806) and women (AUC=0.807) compared to non-stratification (AUC=0.739). In conclusion, we have shown that there are differences in biomarker levels between men and women which may impact accurate disease classification of MDD when gender is not taken into account

Resveratrol and metabolic health in COPD:A proof-of-concept randomized controlled trial

Background: Patients with COPD are often characterized by disturbed metabolic health which is reflected in altered body composition. Current studies in healthy subjects suggest that resveratrol improves metabolic health by enhancing muscle mitochondrial function and adipose tissue morphology. The primary objective was to investigate the effect of four weeks resveratrol supplementation on muscle mitochondrial function in patients with COPD. Secondary objectives were to investigate the effect of resveratrol on adipose tissue inflammatory and metabolic gene expression, systemic inflammation and body composition in patients with COPD. Methods: In a double-blind randomized placebo-controlled proof-of-concept study, 21 COPD patients (FEVi: 53 +/- 15% predicted; age: 67 +/- 9 years and BMI: 24.5 +/- 3.3 kg/m(2)) received resveratrol (150 mg/day) or placebo for four weeks. Before and after intervention, blood samples, quadriceps muscle and subcutaneous abdominal fat biopsies were obtained for metabolic and inflammatory profiling. Body composition was assessed by dual energy X-ray absorptiometry. Results: Muscle mitochondrial biogenesis regulators AMPK, SIRT1 and PGC-1 alpha as well as mitochondrial respiration, Oxphos complexes, oxidative enzyme activities and kynurenine aminotransferases were not improved by resveratrol. Plasma high-sensitive C-reactive protein and kynurenine did not change after resveratrol supplementation. Adipose tissue inflammatory markers were unaffected by resveratrol, while markers of glycolysis and lipolysis were significantly increased compared to placebo supplementation. Body weight decreased after resveratrol supplementation (resveratrol -0.95 +/- 1.01 kg vs placebo -0.16 +/- 0.66 kg, p = 0.049) due to a reduction in lean mass (resveratrol -1.79 +/- 1.67 kg vs 0.37 +/- 0.86 kg, p = 0.026). Conclusion: We do not confirm previously reported positive effects of resveratrol on skeletal muscle mitochondrial function in patients with COPD, but show an unexpected decline in lean mass. (C) 2020 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved