Evolution of field spiral galaxies up to redshifts z=1

We have gained VLT/FORS spectra and HST/ACS images of a sample of 220 distant field spiral galaxies. Spatially resolved rotation curves were extracted and fitted with synthetic velocity fields that take into account all geometric and observational effects, like blurring due to the slit width and seeing influence. The maximum rotation velocity Vmax could be determined for 124 galaxies that cover the redshift range 0.1<z<1.0. The luminosity-rotation velocity distribution of this sample is offset from the Tully-Fisher relation (TFR) of local low-mass spirals, whereas the distant high-mass spirals are compatible with the local TFR. We show that the slope of the local and the intermediate-z TFR would be in compliance if its scatter decreased by more than a factor of 3 between z~0.5 and z~0. On the other hand, the distant low-luminosity disks have much lower stellar M/L ratios than their local counterparts, while high-luminosity disks barely evolved in M/L over the covered redshift range. This could be the manifestation of the "downsizing" effect, i.e. the succesive shift of the peak of star formation from high-mass to low-mass galaxies towards lower redshifts. This trend might be canceled out in the TF diagram due to the simultaneous evolution of multiple parameters. We also estimate the ratios between stellar and total masses, finding that these remained constant since z=1, as would be expected in the context of hierarchically growing structure. (Abridged)Comment: 20 pages, 5 figures, ApJ, accepte

MegaMorph: classifying galaxy morphology using multi-wavelength S\'ersic profile fits

Aims. This work investigates the potential of using the wavelength-dependence of galaxy structural parameters (S\'ersic index, n, and effective radius, Re) to separate galaxies into distinct types. Methods. A sample of nearby galaxies with reliable visual morphologies is considered, for which we measure structural parameters by fitting multi-wavelength single-S\'ersic models. Additionally, we use a set of artificially redshifted galaxies to test how these classifiers behave when the signal-to-noise decreases. Results. We show that the wavelength-dependence of n may be employed to separate visually-classified early- and late-type galaxies, in a manner similar to the use of colour and n. Furthermore, we find that the wavelength variation of n can recover galaxies that are misclassified by these other morphological proxies. Roughly half of the spiral galaxies that contaminate an early-type sample selected using (u-r) versus n can be correctly identified as late-types by N, the ratio of n measured in two different bands. Using a set of artificially-redshifted images, we show that this technique remains effective up to z ~ 0.1. N can therefore be used to achieve purer samples of early-types and more complete samples of late-types than using a colour-n cut alone. We also study the suitability of R, the ratio of Re in two different bands, as a morphological classifier, but find that the average sizes of both early- and late-type galaxies do not change substantially over optical wavelengths.Comment: 6 pages, 2 figures, 2 tables, Accepted for publication in A&

Effectiveness of pneumococcal conjugate vaccine and rotavirus vaccine introduction into the South African public immunisation programme

KMImmunisation has contributed greatly to the control of vaccine-preventable diseases and therefore to improvements in health and survival, especially among young children, and remains one of the most successful and cost-effective public health interventions. This remains true for many of the newer, more expensive vaccines. Vaccines against invasive pneumococcal disease and rotavirus infection were introduced into the South African Expanded Programme on Immunization in April 2009. This article describes the rationale for and process of the introduction of these two vaccines, pneumococcal conjugate vaccine and rotavirus vaccine. It also aims to evaluate the success of and challenges related to their introduction, in terms of both achieving universal coverage and improving survival and health in South African children

How well does Anorexia Nervosa fit with personal values? An exploratory study.

BACKGROUND: Despite an increasing clinical interest in the use of personal values as a motivational tool in psychological therapies for Anorexia Nervosa (AN), research is limited. This study explored personal values among individuals with AN, with a particular focus on the 'fit' between participants' values and their AN. METHODS: A qualitative research design was employed in this study. In-depth, semi-structured interviews were carried out among eight female outpatients and inpatients with a diagnosis of AN or Eating Disorder Not Otherwise Specified - AN type (EDNOS-AN type). Data was analysed using Interpretative Phenomenological Analysis (IPA; Smith, Jarman & Osborne, 1999). RESULTS: Three super-ordinate themes emerged from analysis: 'Balancing Values' (difficulty finding balance in relating to and acting on values), 'Congruence and Clashes between AN and Values' (experiences of AN representing a mixed-fit with values) and 'From Ambivalence to Motivation' (ambivalence toward both AN and recovery - in the context of its mixed-fit with values - and experiences of values as a motivational tool in recovery). CONCLUSIONS: Study findings support a role for psychological therapies in working with personal values as a means of promoting recovery in AN, through supporting individuals to explore AN's workability in the context of their values. Further research investigating the optimal stage of treatment to work with values as a motivational tool is warranted

Galaxy bimodality versus stellar mass and environment

We analyse a z<0.1 galaxy sample from the Sloan Digital Sky Survey focusing on the variation of the galaxy colour bimodality with stellar mass and projected neighbour density Sigma, and on measurements of the galaxy stellar mass functions. The characteristic mass increases with environmental density from about 10^10.6 Msun to 10^10.9 Msun (Kroupa IMF, H_0=70) for Sigma in the range 0.1--10 per Mpc^2. The galaxy population naturally divides into a red and blue sequence with the locus of the sequences in colour-mass and colour-concentration index not varying strongly with environment. The fraction of galaxies on the red sequence is determined in bins of 0.2 in log Sigma and log mass (12 x 13 bins). The red fraction f_r generally increases continuously in both Sigma and mass such that there is a unified relation: f_r = F(Sigma,mass). Two simple functions are proposed which provide good fits to the data. These data are compared with analogous quantities in semi-analytical models based on the Millennium N-body simulation: the Bower et al. (2006) and Croton et al. (2006) models that incorporate AGN feedback. Both models predict a strong dependence of the red fraction on stellar mass and environment that is qualitatively similar to the observations. However, a quantitative comparison shows that the Bower et al. model is a significantly better match; this appears to be due to the different treatment of feedback in central galaxies.Comment: 19 pages, 17 figures; accepted by MNRAS, minor change

Inpatient case fatality rates improvements in children under 5: Diarrhoeal disease, pneumonia and severe acute malnutrition

Data on the number of admissions and deaths in children aged under 5 years from diarrhoea, pneumonia and severe acute malnutrition are routinely collected through the District Health Information System. These data, and the associated case fatality rates, are available for all public sector hospitals in South Africa (SA), and can be compared over time, as well as across different settings. This article presents these data for the period 2011/12 - 2016/17. It reflects on the remarkable improvements in these case fatality rates, and the likely reasons for their declines across all provinces. The article concludes by identifying the actions that need to be taken to ensure that SA achieves the Sustainable Development Goal aim of ending preventable child deaths by 2030

Computer program performs stiffness matrix structural analysis

Computer program generates the stiffness matrix for a particular type of structure from geometrical data, and performs static and normal mode analyses. It requires the structure to be modeled as a stable framework of uniform, weightless members, and joints at which loads are applied and weights are lumped

Sep acceleration in CME driven shocks using a hybrid code

WOS:000341172100009 (Nº de Acesso Web of Science)We perform hybrid simulations of a super-Alfvénic quasi-parallel shock, driven by a coronal mass ejection (CME), propagating in the outer coronal/solar wind at distances of between 3 to 6 solar radii. The hybrid treatment of the problem enables the study of the shock propagation on the ion timescale, preserving ion kinetics and allowing for a self-consistent treatment of the shock propagation and particle acceleration. The CME plasma drags the embedded magnetic field lines stretching from the sun, and propagates out into interplanetary space at a greater velocity than the in situ solar wind, driving the shock, and producing very energetic particles. Our results show that electromagnetic Alfvén waves are generated at the shock front. The waves propagate upstream of the shock and are produced by the counter-streaming ions of the solar wind plasma being reflected at the shock. A significant fraction of the particles are accelerated in two distinct phases: first, particles drift from the shock and are accelerated in the upstream region, and second, particles arriving at the shock get trapped and are accelerated at the shock front. A fraction of the particles diffused back to the shock, which is consistent with the Fermi acceleration mechanism