Is the Sun Embedded in a Typical Interstellar Cloud?

The physical properties and kinematics of the partially ionized interstellar material near the Sun are typical of warm diffuse clouds in the solar vicinity. The interstellar magnetic field at the heliosphere and the kinematics of nearby clouds are naturally explained in terms of the S1 superbubble shell. The interstellar radiation field at the Sun appears to be harder than the field ionizing ambient diffuse gas, which may be a consequence of the low opacity of the tiny cloud surrounding the heliosphere. The spatial context of the Local Bubble is consistent with our location in the Orion spur.Comment: "From the Outer Heliosphere to the Local Bubble", held at International Space Sciences Institute, October 200

Toward a Multifaceted Heuristic of Digital Reading to Inform Assessment, Research, Practice, and Policy

In this commentary, the author explores the tension between almost 30 years of work that has embraced increasingly complex conceptions of digital reading and recent studies that risk oversimplifying digital reading as a singular entity analogous with reading text on a screen. The author begins by tracing a line of theoretical and empirical work that both informs and complicates our understanding of digital literacy and, more specifically, digital reading. Then, a heuristic is proposed to systematically organize, label, and define a multifaceted set of increasingly complex terms, concepts, and practices that characterize the spectrum of digital reading experiences. Research that informs this heuristic is used to illustrate how more precision in defining digital reading can promote greater clarity across research methods and advance a more systematic study of promising digital reading practices. Finally, the author discusses implications for assessment, research, practice, and policy

Risk Factors for End-Stage Kidney Disease After Pediatric Liver Transplantation

Adult liver transplant (LT) recipients commonly develop advanced kidney disease. However, burden of end-stage kidney disease (ESKD) after pediatric LT has not been well-described. We performed a retrospective cohort study of pediatric LTs in the US from 1990–2010. Multivariable Cox regression models were fit to determine risk factors for ESKD and death. 8976 children received LTs. During median follow-up of 7.8 years, 2005 (22%) subjects died (mortality rate 26.1 cases/1000 person-years); 167 (2%) developed ESKD (incidence rate 2.2 cases/1000 person-years). Risk factors for ESKD included older age at LT (highest risk age>15 vs <5 years, HR=4.94, p<0.001), hepatitis C (HR 2.79, p=0.004), liver re-transplant (HR 2.67, p<0.001), eGFR pre-LT <60 vs ≥60 (HR 2.37, p<0.001), hepatitis B (HR 2.25, p=0.027), black race (HR 1.46, p=0.046), and male sex (HR 1.44, p=0.022). LT recipients with ESKD had increased risk of mortality (HR 2.37, p<0.001). Among pediatric LT recipients, rate of ESKD was lower than among adults and far exceeded by rate of death, however follow-up time in this study may underestimate lifetime burden of ESKD. Although uncommon, ESKD was highly associated with mortality. Pediatric LT recipients should be routinely monitored for kidney disease, particularly those at highest risk of ESKD

Abstract 5093: The molecular genetics of radiogenic breast cancer

Abstract The aim of this study is to identify the underlying molecular genetic mechanisms of radiation induced breast carcinogenesis. Studies have shown that women exposed to ionising radiation at a young age are more at risk of developing breast cancer than older women exposed to the same level of radiation. Higher levels of estrogen are present in young women and estrogen has a known transforming effect on breast epithelial cells. One hypothesis suggests that radiation and estrogen synergise to drive breast epithelial cell transformation. We have developed an in vitro model of radiation-induced breast epithelial cell transformation in order to investigate genetic alterations associated with breast cell transformation. The immortalised, non-transformed breast epithelial cell line MCF-10A was exposed to fractionated doses of X-rays in the presence or absence of exogenous estrogen. We have shown that radiation treated cells display evidence of transformation, including loss of contact inhibition, increased cell invasion, disrupted acini formation and tumor formation in immunocompromised Rag2−/− γ−/− mice. Analysis of radiation treated cells by SNP array karyotyping identified focal gene deletion (EP300 and OCT-1) and amplification (c-MYC) which may be linked to radiation-induced breast cell transformation. Gene deletion and amplification was confirmed by Fluorescent In Situ Hybridization analysis and alterations in expression have been confirmed by western analysis. EP300 is a transcriptional co-activator and a putative tumor suppressor. Somatic mutations in EP300 have been found in solid tumours and the gene is located in a region of chromosome 22 affected by loss of heterozygosity in numerous cancers. Oct-1 encodes an octamer binding transcription factor that has been associated with regulating DNA damage response through interactions with BRCA1 and GADD45. c-MYC is a known proto-oncogene that encodes a transcription factor involved in cell proliferation, cell cycle regulation and apoptosis. Analysis of our in vitro model of radiation-induced breast epithelial cell transformation has identified genetic alterations that have established roles in mediating cellular response to DNA damage and which might be key events in the development of radiogenic breast cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5093. doi:10.1158/1538-7445.AM2011-5093</jats:p