61 resultados para 412


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Background and purpose: The addition of gold nanoparticles (GNPs) to tumours leads to an increase in dose due to their high density and energy absorption coefficient, making it a potential radiosensitiser. However, experiments have observed radiosensitisations significantly larger than the increase in dose alone, including at megavoltage energies where gold's relative energy absorption is lowest. This work investigates whether GNPs create dose inhomogeneities on a sub-cellular scale which combine with non-linear dose dependence of cell survival to be the source of radiosensitisation at megavoltage energies.

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Rural point sources of phosphorus (P), including septic tank systems, provide a small part of the overall phosphorus budget to surface waters in agricultural catchments but can have a disproportionate impact on the low flow P concentration of receiving rivers. This has particular importance as the discharges are approximately constant into receiving waters and these have restricted dilution capacity during ecologically sensitive summer periods. In this study, a number of identified high impact septic systems were replaced with modern sequential batch reactors in three rural catchments during a monitoring period of 4 years. Sub-hourly P monitoring was conducted using bankside-analysers. Results show that strategic replacement of defective septic tank systems with modern systems and polishing filters decreased the low flow P concentration of one catchment stream by 0.032 mg TP L- 1 (0.018 mg TRP L- 1) over the 4 years. However two of the catchment mitigation efforts were offset by continued new-builds that increased the density of septic systems from 3.4 km- 2 to 4.6 km- 2 and 13.8 km- 2 to 17.2 km- 2 and subsequently increased low flow P concentrations. Future considerations for septic system mitigation should include catchment carrying capacity as well as technology changes.

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The texts adapted for, printed for and marketed to children and youths in the 16th and 17th centuries, the books read by boys and girls in this period, and writings by Renaissance children constitute the literature of early modern childhoods. Yet traditional histories of children’s literature, posing narrow definitions of this genre, have largely overlooked this period. In the past decade, fresh work by early modern scholars attending to the diverse elements of the literature of early modern childhoods has flourished. This essay evaluates the absence of early modern children’s literature from early studies and considers the ways in which this recent work in Renaissance studies has vitally transformed the field through its exploration of alternative definitions of childhood and children’s literature. This work is at an early stage but it has placed the interconnections between early modern childhoods and children’s literature at the centre of both Renaissance studies and childhood studies and has established key topics for future research.

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Coeliac disease is often under-diagnosed, particularly in cases which are atypical or asymptomatic.

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Coronary heart disease is the commonest cause of death in Northern Ireland, but few data exist on the incidence of risk factors in young adult students and non-students.

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Alzheimer's disease (AD) is characterised by the extensive deposition of amyloid beta (Aß) within the parenchyma and vasculature of the brain. It is hypothesised that a dysfunction in Aß degradation and/or its removal from the brain may result in accumulation as plaques. Low density lipoprotein receptor-related protein-1 (LRP-1) is a multifunctional receptor shown to be involved in cholesterol metabolism but also the removal of Aß from the brain. Its ability to transport Aß from the brain to the periphery has made it an attractive candidate for involvement in Alzheimer's disease (AD). We have assessed the frequencies of 9 tag- SNPs and the commonly studied synonymous SNP within exon 3 (rs1799986) in a multi-centre AD/control cohort and performed haplotype analysis. We found no evidence from a combined total of 412 controls and 1057 AD patients to support the involvement of LRP-1 variation, including the most commonly studied variant in rs1799986 in conferring genetic susceptibility to increased risk of AD.

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The protective role of strength of group identity was examined for youth in a context of protracted political conflict. Participants included 814 adolescents (Mage = 13.61, SD = 1.99 at Time 1) participating in a longitudinal study in Belfast, Northern Ireland. Utilizing hierarchical linear modeling, the results show that the effect of exposure to sectarian antisocial behaviors has a stronger effect on youth emotion problems for older adolescents. The results also show that youth with higher strength of group identity reported fewer emotion problems in the face of sectarian antisocial behavior but that this buffering effect is stronger for Protestants compared to Catholics. Implications are discussed for understanding the role of social identity in postaccord societies.