137 resultados para 293
Resumo:
Welfare-to-work policy in the UK sees ‘choice’ regarding lone parents’ employment decisions increasingly defined in terms of powers of selection between options within active labour market programmes, with constraints on the option of non-market activity progressively tightened. In this paper, we examine the wider choice agenda in public services in relation to lone-parent employment, focusing on the period of welfare reform following the 2007 Freud review of welfare provision. Survey data is used to estimate the extent to which recent policies promoting compulsory job search by youngest dependent child age map onto lone parents' own stated decision-making regarding if and when to enter the labour market. The findings indicate a substantial proportion of lone parents targeted by policy reform currently do not want a job and that their main reported reason is that they are looking after their children. Economically inactive lone mothers also remain more likely to have other chronic employment barriers, which traverse dependent child age categories. Some problems, such as poor health, sickness or disability, are particularly acute among those with older dependent children who are the target of recent activation policy.
Resumo:
Madagascar is home to numerous endemic species and lineages, but the processes that have contributed to its endangered diversity are still poorly understood. Evidence is accumulating to demonstrate the importance of Tertiary dispersal across varying distances of oceanic barriers, supplementing vicariance relationships dating back to the Cretaceous, but these hypotheses remain tentative in the absence of well-supported phylogenies. In the Papilio demoleus group of swallowtail butterflies, three of the five recognized species are restricted to Madagascar, whereas the remaining two species range across the Afrotropical zone and southern Asia plus Australia. We reconstructed phylogenetic relationships for all species in the P. demoleus group, as well as 11 outgroup Papilio species, using 60 morphological characters and about 4 kb of nucleotide sequences from two mitochondrial (cytochrome oxidase I and II) and two nuclear (wg and EF-1a) genes. Of the three endemic Malagasy species, the two that are formally listed as endangered or at risk represented the most basal divergences in the group, while the more common third endemic was clearly related to African P. demodocus. The fifth species, P. demoleus, showed little differentiation across southern Asia, but showed divergence from its subspecies sthenelus in Australia. Dispersal-vicariance analysis using cladograms derived from morphology and three independent genes indicated a Malagasy diversification of lime swallowtails in the middle Miocene. Thus, diversification processes on the island of Madagascar may have contributed to the origin of common butterflies that now occur throughout much of the Old World tropical and subtemperate regions. An alternative hypothesis, that Madagascar is a refuge for ancient lineages resulting from successive colonizations from Africa, is less parsimonious and does not explain the relatively low continental diversity of the group.
Resumo:
1. The risk of parasitism and infectious disease is expected to increase with population density as a consequence of positive density-dependent transmission rates. Therefore, species that encounter large fluctuations in population density are predicted to exhibit plasticity in their immune system, such that investment in costly immune defences is adjusted to match the probability of exposure to parasites and pathogens (i.e. density-dependent prophylaxis).
Resumo:
RNA polymerase I (Pol I) produces large ribosomal RNAs (rRNAs). In this study, we show that the Rpa49 and Rpa34 Pol I subunits, which do not have counterparts in Pol II and Pol III complexes, are functionally conserved using heterospecific complementation of the human and Schizosaccharomyces pombe orthologues in Saccharomyces cerevisiae. Deletion of RPA49 leads to the disappearance of nucleolar structure, but nucleolar assembly can be restored by decreasing ribosomal gene copy number from 190 to 25. Statistical analysis of Miller spreads in the absence of Rpa49 demonstrates a fourfold decrease in Pol I loading rate per gene and decreased contact between adjacent Pol I complexes. Therefore, the Rpa34 and Rpa49 Pol I–specific subunits are essential for nucleolar assembly and for the high polymerase loading rate associated with frequent contact between adjacent enzymes. Together our data suggest that localized rRNA production results in spatially constrained rRNA production, which is instrumental for nucleolar assembly.
Resumo:
Self-help (or mutual aid) processes play a substantial role in the reintegration of stigmatized individuals, in particular, a substantial self-help movement has developed around addiction recovery. Prisoners and ex-prisoners have also established self-help groups around the world. This paper focuses in particular on the role of self-help principles and practices among “politically motivated” former prisoners from all sides of the Northern Irish conflict. The concept of self-help and its application to former prisoners are analysed theoretically, then applied to the Northern Irish case study through a series of interviews with ex-prisoners whose incarceration has been related to the conflict in Northern Ireland. We draw on the implications of this case study for wider issues of reintegration for politically motivated and ordinary prisoners.
Resumo:
center dot Inappropriate antimicrobial use has been associated with increased morbidity and hospital costs.