23 research outputs found
Density waves and star formation in grand design spirals
HII regions in the arms of spiral galaxies are indicators of recent
star-forming processes. They may have been caused by the passage of the density
wave or simply created by other means near the arms. The study of these regions
may give us clues to clarifying the controversy over the existence of a
triggering scenario, as proposed in the density wave theory. Using H
direct imaging, we characterize the HII regions from a sample of three grand
design galaxies: NGC5457, NGC628 and NGC6946. Broad band images in R and I were
used to determine the position of the arms. The HII regions found to be
associated with arms were selected for the study. The age and the star
formation rate of these HII regions was obtained using measures on the
H line. The distance between the current position of the selected HII
regions and the position they would have if they had been created in the centre
of the arm is calculated. A parameter, T, which measures whether a region was
created in the arm or in the disc, is defined. With the help of the T parameter
we determine that the majority of regions were formed some time after the
passage of the density wave, with the regions located `behind the arm' (in the
direction of the rotation of the galaxy) the zone they should have occupied had
they been formed in the centre of the arm. The presence of the large number of
regions created after the passage of the arm may be explained by the effect of
the density wave, which helps to create the star-forming regions after its
passage. There is clear evidence of triggering for NGC5457 and a co-rotation
radius is proposed. A more modest triggering seems to exist for NGC628 and non
significant evidence of triggering are found for NGC6946.Comment: 10 pages, 20 figures, accepted for publication in A&
Participatory budgeting, community engagement and impact on public services in Scotland
The institutional engagement and analysis needed to effectively integrate the requirements of equality legislation into participatory budgeting (PB) processes requires a transformational approach. Equality processes appear to exist in parallel with PB activity, rather than being operationalized as integral to the objectives and character of PB activity at local level. This paper proposes that PB and the Public Sector Equality Duty (PSED) in the Equality Act 2010 share a transformative intent and potential, but that this is undermined by siloed thinking on equalities and enduring discriminatory behaviour and practices. The paper concludes with propositions for aligning the conceptual links between equality and community empowerment and, thereby, participation in local financial decision-making in practice
Evaluation of iron status in European adolescents through biochemical iron indicators: the HELENA Study
BACKGROUND/OBJECTIVES: To assess the iron status among European adolescents through selected biochemical parameters in a cross-sectional study performed in 10 European cities. SUBJECTS/METHODS: Iron status was defined utilising biochemical indicators. Iron depletion was defined as low serum ferritin (SF8.5 mg/l) plus iron depletion. Iron deficiency anaemia (IDA) was defined as ID with haemoglobin (Hb) below the WHO cutoff for age and sex: 12.0 g/dl for girls and for boys aged 12.5-14.99 years and 13.0 g/dl for boys aged â„15 years. Enzyme linked immunosorbent assay was used as analytical method for SF, sTfR and C-reactive protein (CRP). Subjects with indication of inflammation (CRP >5 mg/l) were excluded from the analyses. A total of 940 adolescents aged 12.5-17.49 years (438 boys and 502 girls) were involved. RESULTS: The percentage of iron depletion was 17.6%, significantly higher in girls (21.0%) compared with boys (13.8%). The overall percentage of ID and IDA was 4.7 and 1.3%, respectively, with no significant differences between boys and girls. A correlation was observed between log (SF) and Hb (r = 0.36, P < 0.01), and between log (sTfR) and mean corpuscular haemoglobin (r = -0.30, P < 0.01). Iron body stores were estimated on the basis of log (sTfR/SF). A higher percentage of negative values of body iron was recorded in girls (16.5%) with respect to boys (8.3%), and body iron values tended to increase with age in boys, whereas the values remained stable in girls. CONCLUSIONS: To ensure adequate iron stores, specific attention should be given to girls at European level to ensure that their dietary intake of iron is adequate.status: publishe