The fraction of early-type galaxies in low redshift groups and clusters of galaxies

We examine the fraction of early-type (and spiral) galaxies found in groups and clusters of galaxies as a function of dark matter halo mass. We use morphological classifications from the Galaxy Zoo project matched to halo masses from both the C4 cluster catalogue and the Yang et al (2007) group catalogue. We find that the fraction of early-type (or spiral) galaxies remains constant (changing by less than 10%) over three orders of magnitude in halo mass (13<log MH/Msol/h<15.8). This result is insensitive to our choice of halo mass measure, from velocity dispersions or summed optical luminosity. Furthermore, we consider the morphology-halo mass relations in bins of galaxy stellar mass M*, and find that while the trend of constant fraction remains unchanged, the early-type fraction amongst the most massive galaxies (11<log M*/Msol/h <12) is a factor of three greater than lower mass galaxies (10<logM*/Msol/h<10.7). We compare our observational results with those of simulations presented in De Lucia et al (2011), as well as previous observational analyses, and semi-analytic bulge (or disc) dominated galaxies from the Millennium Simulation. We find the simulations recover similar trends as observed, but may over-predict the abundances of the most massive bulge dominated (early-type) galaxies. Our results suggest that most morphological transformation is happening on the group scale before groups merge into massive clusters. However, we show that within each halo a morphology-density relation remains: it is summing the total fraction to a self-similar scaled radius which results in a flat morphology-halo mass relationship.Comment: 9 page, 5 figures, modified to match accepted version (MNRAS

Electrochemical formation of N–substituted polypyrrole nanowires, microwires and open microtubes and their decoration with copper structures

The substituted pyrrole monomer, N–(2–cyanoethyl)pyrrole, was electropolymerised in a 70% water and 30% ethanol solution with ClO4– and H2PO4– as the dopant species to give nanowires at short electropolymerisation times and microwires at longer deposition periods. On adding toluene to the electropolymerisation solution, hollow microtubes were formed. This was attributed to the adsorption of toluene droplets at the electrode surface which served to separate the dopants from the monomer, with the monomer being highly soluble in the toluene droplet and the inorganic dopants soluble in the water/ethanol mixture. As a result electropolymerisation was confined to the toluene-water/ethanol interface. These polymer systems exhibit redox activity with the oxidation wave centred at about 0.40 V vs SCE, and the broader reduction wave positioned between 0.75 V and 0.25 V vs SCE. Although N-substitution reduces the conductivity of the polymer, various copper deposits, including cubes, leaves and hierarchical structures were deposited at the microwires and microtubes using high overpotentials. The hierarchical structures were wrapped around the microtubes at considerable distances, typically 3–4 µm, from the substrate

The views of general practitioners and practice nurses towards the barriers and facilitators of proactive, internet-based chlamydia screening for reaching young heterosexual men

Background: Chlamydia trachomatis is a common bacterial sexually transmitted infection (STI), which disproportionately affects young people under 25 years. Commonly, more women are offered screening than men. This study obtained the views of general practitioners and practice nurses towards Internet-based screening and assessed levels of support for the development of proactive screening targeting young heterosexual men via the Internet. Methods: Semi-structured telephone interviews with 10 general practitioners and 8 practice nurses, across Central Scotland. Topics covered: experience of screening heterosexual men for chlamydia, views on the use of the Internet as a way to reach young men for chlamydia screening, beliefs about the potential barriers and facilitators to Internet-based screening. Transcripts from audio recordings were analysed with Framework Analysis, using QSR NVivo10. Results: Experiences of chlamydia screening were almost exclusively with women, driven by the nature of consultations and ease of raising sexual health issues with female patients; few practice nurses reported seeing men during consultations. All participants spoke in favour of Internet-based screening for young men. Participants reported ease of access and convenience as potential facilitators of an Internet-based approach but anonymity and confidentiality could be potential barriers and facilitators to the success of an Internet approach to screening. Concerns over practical issues as well as those pertaining to gender and socio-cultural issues were raised. Conclusions: Awareness of key barriers and facilitators, such as confidentiality, practicality and socio-cultural influences, will inform the development of an Internet-based approach to screening. However, this approach may have its limits in terms of being able to tackle wider social and cultural barriers, along with shifts in young people's and health professionals' attitudes towards screening. Nevertheless, employing innovative efforts as part of a multi-faceted approach is required to ensure effective interventions reach the policy agenda

Longitudinal Bioluminescence Imaging of Primary Versus Abdominal Metastatic Tumor Growth in Orthotopic Pancreatic Tumor Models in NSG Mice

Objectives: The purpose of the present study was to develop and validate noninvasive bioluminescence imaging methods for differentially monitoring primary and abdominal metastatic tumor growth in mouse orthotopic models of pancreatic cancer. Methods: A semiautomated maximum entropy segmentation method was implemented for the primary tumor region of interest, and a rule-based method for manually drawing a region of interest for the abdominal metastatic region was developed for monitoring tumor growth in orthotopic models of pancreatic cancer. The 2 region-of-interest methods were validated by having 2 observers independently segment Panc-1 tumors, and the results were compared with the number of mesenteric lymph node nodules and histopathologic assessment of liver metastases. The findings were extended to orthotopic tumors of the more metastatic MIA PaCa-2 and AsPC-1 cells where separate groups of animals were implanted with different numbers of cells. Results: The results demonstrated that the segmentation methods were highly reliable, reproducible, and robust and allowed statistically significant discrimination in the growth rates of primary and abdominal metastatic tumors of different cell lines implanted with different numbers of cells. Conclusions: The present results demonstrate that primary tumors and abdominal metastatic foci in orthotopic pancreatic cancer models can be reliably quantified separately and noninvasively over time with bioluminescence imaging

Total anomalous pulmonary venous connection: Outcome of postoperative pulmonary venous obstruction

ObjectivePulmonary venous obstruction (PVO) is an important cause of late mortality in total anomalous pulmonary venous connection (TAPVC). We aimed to describe current practices for the management of postoperative PVO and the efficacy of the different interventional procedures.MethodsWe conducted a retrospective international collaborative population-based study involving 19 pediatric cardiac centers in the United Kingdom, Ireland, and Sweden. Patients with TAPVC born between January 1, 1998, and December 31, 2004, were identified. Patients with functionally univentricular circulation or atrial isomerism were excluded. All available data and images were reviewed.ResultsOf 406 patients undergoing repair of TAPVC, 71 (17.5%) had postoperative PVO. The diagnosis was made within 6 months of surgery in 59 (83%) of the 71 patients. In 12, serial imaging documented change in appearance of the pulmonary veins. Good-sized pulmonary veins can progress to diffusely small veins and rarely atresia. Patients presenting after 6 months had less severe disease; all are alive at most recent follow-up. Fifty-six (13.8%) of 406 patients underwent intervention for postoperative PVO: 44 had surgical treatment and 12 had an initial catheter intervention. One half underwent 1 or more reinterventions. Three-year survival for patients with postoperative PVO was 58.7% (95% confidence intervals, 46.2%-69.2%) with a trend that those having a surgical strategy did better (P = .083). Risk factors for death included earlier presentation after TAPVC repair, diffusely small pulmonary veins at presentation of postoperative PVO, and an increased number of lung segments affected by obstruction.ConclusionsPostoperative PVO tends to appear in the first 6 months after TAPVC repair and can be progressive. Early intervention for PVO may be indicated before irreversible secondary changes occur

The association between preeclampsia and childhood development and behavioural outcomes

Objectives: To examine the associations between preeclampsia and longitudinal child developmental and behavioural outcomes using data from a nationally representative study of children living in Ireland. Methods: We used maternal-reported data from the Growing Up in Ireland longitudinal study of children. Data on preeclampsia and preeclampsia + small for gestational age (SGA) were collected when children were 9-months old. Data on child development and behavioural outcomes were collected at 9-months using the Ages and Stages Questionnaire (ASQ), and at 3 years, 5 years and 7–8 years using the Strengths and Difficulties Questionnaire (SDQ). Multivariate logistic regression analysis was used to examine the association between preeclampsia exposure and failure of ASQ domains, and abnormal SDQ domains. Linear spline multilevel models were used to examine the association between preeclampsia and preeclampsia + SGA and repeated measures of SDQ. All models controlled for several perinatal and sociodemographic factors. Results: A total of 10,692 children were included in the study at baseline, representing a weighted total of 70,791. Multivariate logistic regression suggested that preeclampsia was not associated with failing any ASQ domain. Preeclampsia was associated with abnormal SDQ cut-off of emotional (≥ 5) and hyperactivity (≥ 7) domains at age 5 years only. In the linear spline model, mean SDQ score was higher at each time point in exposed groups. Conclusions for Practice: While we did not find strong evidence of associations between preeclampsia and child developmental and behavioural outcomes overall, some associations between preeclampsia-exposure and subtle behavioural issues did persist. Further research is needed to replicate these findings, and determine the clinical significance of changes in SDQ scores

Relationship of Race/Ethnicity and Survival after Single Umbilical Cord Blood Transplantation for Adults and Children with Leukemia and Myelodysplastic Syndromes

The relationship of race/ethnicity with outcomes of umbilical cord blood transplantation (UCBT) is not well known. We analyzed the association between race/ethnicity and outcomes of unrelated single UCBT for leukemia and myelodysplastic syndromes. Our retrospective cohort study consisted of 885 adults and children (612 whites, 145 blacks, and 128 Hispanics) who received unrelated single UCBT for leukemia and myelodysplastic syndromes between 1995 and 2006 and were reported to the Center for International Blood and Marrow Transplant Research. A 5-6/6 HLA-matched unit with a total nucleated cell count infused of ≥2.5 × 107/kg was given to 40% white and 42% Hispanic, but only 21% black patients. Overall survival at 2 years was 44% for whites, 34% for blacks, and 46% for Hispanics (P = .008). In multivariate analysis adjusting for patient, disease, and treatment factors (including HLA match and cell dose), blacks had inferior overall survival (relative risk of death, 1.31; P = .02), whereas overall survival of Hispanics was similar (relative risk, 1.03; P = .81) to that of whites. For all patients, younger age, early-stage disease, use of units with higher cell dose, and performance status ≥80 were independent predictors of improved survival. Black patients and white patients infused with well-matched cords had comparable survival; similarly, black and white patients receiving units with adequate cell dose had similar survival. These results suggest that blacks have inferior survival to whites after single UCBT, but outcomes are improved when units with a higher cell dose are used

Galaxy Zoo: Passive Red Spirals

We study the spectroscopic properties and environments of red spiral galaxies found by the Galaxy Zoo project. By carefully selecting face-on, disk dominated spirals we construct a sample of truly passive disks (not dust reddened, nor dominated by old stellar populations in a bulge). As such, our red spirals represent an interesting set of possible transition objects between normal blue spirals and red early types. We use SDSS data to investigate the physical processes which could have turned these objects red without disturbing their morphology. Red spirals prefer intermediate density regimes, however there are no obvious correlations between red spiral properties and environment - environment alone is not sufficient to determine if a spiral will become red. Red spirals are a small fraction of spirals at low masses, but are a significant fraction at large stellar masses - massive galaxies are red independent of morphology. We confirm that red spirals have older stellar popns and less recent star formation than the main spiral population. While the presence of spiral arms suggests that major star formation cannot have ceased long ago, we show that these are not recent post-starbursts, so star formation must have ceased gradually. Intriguingly, red spirals are ~4 times more likely than normal spirals to host optically identified Seyfert or LINER, with most of the difference coming from LINERs. We find a curiously large bar fraction in the red spirals suggesting that the cessation of star formation and bar instabilities are strongly correlated. We conclude by discussing the possible origins. We suggest they may represent the very oldest spiral galaxies which have already used up their reserves of gas - probably aided by strangulation, and perhaps bar instabilities moving material around in the disk.Comment: MNRAS in press, 20 pages, 15 figures (v3

Theoretical Uncertainties due to AGN Subgrid Models in Predictions of Galaxy Cluster Observable Properties

Cosmological constraints derived from galaxy clusters rely on accurate predictions of cluster observable properties, in which feedback from active galactic nuclei (AGN) is a critical component. In order to model the physical effects due to supermassive black holes (SMBH) on cosmological scales, subgrid modeling is required, and a variety of implementations have been developed in the literature. However, theoretical uncertainties due to model and parameter variations are not yet well understood, limiting the predictive power of simulations including AGN feedback. By performing a detailed parameter sensitivity study in a single cluster using several commonly-adopted AGN accretion and feedback models with FLASH, we quantify the model uncertainties in predictions of cluster integrated properties. We find that quantities that are more sensitive to gas density have larger uncertainties (~20% for Mgas and a factor of ~2 for Lx at R500), whereas Tx, Ysz, and Yx are more robust (~10-20% at R500). To make predictions beyond this level of accuracy would require more constraints on the most relevant parameters: the accretion model, mechanical heating efficiency, and size of feedback region. By studying the impact of AGN feedback on the scaling relations, we find that an anti-correlation exists between Mgas and Tx, which is another reason why Ysz and Yx are excellent mass proxies. This anti-correlation also implies that AGN feedback is likely to be an important source of intrinsic scatter in the Mgas-Tx and Lx-Tx relations.Comment: Accepted for publication in MNRA