The relative impact of baryons and cluster shape on weak lensing mass estimates of galaxy clusters

Weak gravitational lensing depends on the integrated mass along the line of sight. Baryons contribute to the mass distribution of galaxy clusters and the resulting mass estimates from lensing analysis. We use the cosmo-OWLS suite of hydrodynamic simulations to investigate the impact of baryonic processes on the bias and scatter of weak lensing mass estimates of clusters. These estimates are obtained by fitting NFW profiles to mock data using MCMC techniques. In particular, we examine the difference in estimates between dark matter-only runs and those including various prescriptions for baryonic physics. We find no significant difference in the mass bias when baryonic physics is included, though the overall mass estimates are suppressed when feedback from AGN is included. For lowest-mass systems for which a reliable mass can be obtained ($M_{200} \approx 2 \times 10^{14}$ $M_{\odot}$), we find a bias of $\approx -10$ per cent. The magnitude of the bias tends to decrease for higher mass clusters, consistent with no bias for the most massive clusters which have masses comparable to those found in the CLASH and HFF samples. For the lowest mass clusters, the mass bias is particularly sensitive to the fit radii and the limits placed on the concentration prior, rendering reliable mass estimates difficult. The scatter in mass estimates between the dark matter-only and the various baryonic runs is less than between different projections of individual clusters, highlighting the importance of triaxiality

Interaction of SET domains with histones and nucleic acid structures in active chromatin

Changes in the normal program of gene expression are the basis for a number of human diseases. Epigenetic control of gene expression is programmed by chromatin modifications—the inheritable “histone code”—the major component of which is histone methylation. This chromatin methylation code of gene activity is created upon cell differentiation and is further controlled by the “SET” (methyltransferase) domain proteins which maintain this histone methylation pattern and preserve it through rounds of cell division. The molecular principles of epigenetic gene maintenance are essential for proper treatment and prevention of disorders and their complications. However, the principles of epigenetic gene programming are not resolved. Here we discuss some evidence of how the SET proteins determine the required states of target genes and maintain the required levels of their activity. We suggest that, along with other recognition pathways, SET domains can directly recognize the nucleosome and nucleic acids intermediates that are specific for active chromatin regions

Patients' perceptions of safety and quality of maternity clinical handover

<p>Abstract</p> <p>Background</p> <p>Maternity clinical handover serves to address the gaps in knowledge existing when transitions between individuals or groups of clinicians occur throughout the antenatal, intra-partum and postnatal period. There are limited published studies on maternity handover and a paucity of information about patients' perceptions of the same. This paper reports postnatal patients' perceptions of how maternity handover contributes to the quality and safety of maternity care.</p> <p>Methods</p> <p>This paper reports on a mixed-methods study consisting of qualitative interviews and quantitative medical record analysis. Thirty English-speaking postnatal patients who gave birth at an Australian tertiary maternity hospital participated in a semi-structured interview prior to discharge from hospital. Interview data were coded thematically using the constant comparative method and managed via NVivo software; this data set was supplemented by medical record data analysed using STATA.</p> <p>Results</p> <p>Almost half of the women were aware of a handover process. Clinician awareness of patient information was seen as evidence that handover had taken place and was seen as representing positive aspects of teamwork, care and communication by participants, all important factors in the perception of quality health care. Collaborative cross-checking, including the use of cognitive artefacts such as hand held antenatal records and patient-authored birth plans, and the involvement of patients and their support people in handover were behaviours described by participants to be protective mechanisms that enhanced quality and safety of care. These human factors also facilitated team situational awareness (TSA), shared decision making and patient motivation in labour.</p> <p>Conclusions</p> <p>This study illustrates that many patients are aware of handover processes. For some patients, evidence of handover, through clinician awareness of information, represented positive aspects of teamwork, care and communication.</p> <p>Cross-checking and cognitive artefacts were observed to support handover. Patient-authored birth plans were described by some to enhance the quality and safety of the handover by providing a 'voice' to the patient in this process. This was a novel and potentially important perspective.</p> <p>Future research involving patients and their support people in supporting and evaluating handover should be considered.</p