Information sheets for patients with acute chest pain: randomised controlled trial

Objectives: To determine whether providing an information sheet to patients with acute chest pain reduces anxiety, improves health related quality of life, improves satisfaction with care, or alters subsequent symptoms or actions. Design: Single centre, non-blinded, randomised controlled trial. Setting: Chest pain unit of an emergency department. Participants: 700 consecutive patients with acute chest pain and no clear diagnosis at initial presentation. Interventions: After a diagnostic assessment patients were randomised to receive either standard verbal advice or verbal advice followed by an information sheet. Main outcome measures: The primary outcome was anxiety (hospital anxiety and depression scale). Secondary outcomes were depression (hospital anxiety and depression scale), health related quality of life (SF-36), patient satisfaction, presentation with further chest pain within one month, lifestyle change (smoking cessation, diet, exercise), further information sought from other sources, and planned healthcare seeeking behaviour in response to further pain. Results 494 of 700 (70.6%) patients responded. Compared with those receiving standard verbal advice those receiving advice and an information sheet had lower mean hospital anxiety and depression scale scores for anxiety (7.61v8.63, difference 1.02, 95% confidence interval 0.20 to 1.84) and depression (4.14 v 5.28, difference 1.14, 0.41 to 1.86) and higher scores for mental health and perception of general health on the SF-36. The information sheet had no significant effect on satisfaction with care, subsequent symptoms, lifestyle change, information seeking, or planned actions in the event of further pain. Conclusions: Provision of an information sheet to patients with acute chest pain can reduce anxiety and depression and improve mental health and perception of general health but does not alter satisfaction with care or other outcomes. Trial registration Current Controlled Trials ISRCTN85248020

Evidence for a molecular cloud origin of gamma-ray bursts: Implications for the nature of star formation in the universe

It appears that the majority of rapidly and well-localized gamma-ray bursts with undetected or dark optical afterglows ("dark bursts") occur in clouds of size R ≳ 10L491/2 pc and mass M ≳ 3 × 105L49 M⊙ where L is the isotropic-equivalent peak luminosity of the optical flash. We show that clouds of this size and mass cannot be modeled as a gas that is bound by pressure equilibrium with a warm or hot phase of the interstellar medium (i.e., a diffuse cloud): such a cloud would be unstable to gravitational collapse, resulting in the collapse and fragmentation of the cloud until a burst of star formation reestablishes pressure equilibrium within the fragments and the fragments are bound by self-gravity (i.e., a molecular cloud). Consequently, dark bursts probably occur in molecular clouds, in which case dark bursts are probably a by-product of this burst of star formation, if the molecular cloud formed recently, and/or the result of lingering or latter generation star formation if the molecular cloud formed some time ago. We then show that if bursts occur in Galactic-like molecular clouds, the column densities of which might be universal, the number of dark bursts can be comparable to the number of bursts with detected optical afterglows: this is what is observed, which suggests that the bursts with detected optical afterglows might also occur in molecular clouds. We confirm this by modeling and constraining the distribution of column densities, measured from absorption of the X-ray afterglow, of the bursts with detected optical afterglows: we find that this distribution is consistent with the expectation for bursts that occur in molecular clouds and is not consistent with the expectation for bursts that occur in diffuse clouds. Consequently, we find that all but perhaps a few bursts, dark or otherwise, probably occur in molecular clouds. Finally, we show that the limited information that is available on the column densities of the dark bursts is not consistent with the idea that the dark bursts occur in the nuclear regions of ultraluminous infrared/submillimeter-bright galaxies, from which we draw conclusions about the nature of star formation in the universe

Optical Bumps in Cosmological GRBs as Supernovae

From both photometric and broadband spectral monitoring of gamma-ray burst (GRB) lightcurve ``bumps,'' particularly in GRB 011121, a strong case grew for a supernova (SN) origin. The GRB-SN connection was finally solidified beyond a reasonable doubt with the discovery that the bump in GRB 030329 was spectroscopically similar to a bright Type Ic SN. In light of this result, I redress the previous SN bump claims and conclude that 1) the distribution of GRB-SN bump peak magnitudes is consistent with the local Type Ibc SNe peak distribution and suggest that 2) the late-time bumps in all long-duration GRBs are likely supernovae.Comment: 5 pages, 2 figures. To be published in Proc. IAU Colloquium #192 ``Supernovae (10 years of SN1993J),'' held 22-26 April 2003, Valencia, Spain. Editors: J.M. Marcaide and K.W. Weiler. Uses svmult.cl

Cornerstones of Sampling of Operator Theory

This paper reviews some results on the identifiability of classes of operators whose Kohn-Nirenberg symbols are band-limited (called band-limited operators), which we refer to as sampling of operators. We trace the motivation and history of the subject back to the original work of the third-named author in the late 1950s and early 1960s, and to the innovations in spread-spectrum communications that preceded that work. We give a brief overview of the NOMAC (Noise Modulation and Correlation) and Rake receivers, which were early implementations of spread-spectrum multi-path wireless communication systems. We examine in detail the original proof of the third-named author characterizing identifiability of channels in terms of the maximum time and Doppler spread of the channel, and do the same for the subsequent generalization of that work by Bello. The mathematical limitations inherent in the proofs of Bello and the third author are removed by using mathematical tools unavailable at the time. We survey more recent advances in sampling of operators and discuss the implications of the use of periodically-weighted delta-trains as identifiers for operator classes that satisfy Bello's criterion for identifiability, leading to new insights into the theory of finite-dimensional Gabor systems. We present novel results on operator sampling in higher dimensions, and review implications and generalizations of the results to stochastic operators, MIMO systems, and operators with unknown spreading domains

Displaying the Heterogeneity of the SN 2002cx-like Subclass of Type Ia Supernovae with Observations of the Pan-STARRS-1 Discovered SN2009ku

SN2009ku, discovered by Pan-STARRS-1, is a Type Ia supernova (SNIa), and a member of the distinct SN2002cx-like class of SNeIa. Its light curves are similar to the prototypical SN2002cx, but are slightly broader and have a later rise to maximum in g. SN2009ku is brighter (~0.6 mag) than other SN2002cx-like objects, peaking at M_V = -18.4 mag - which is still significantly fainter than typical SNeIa. SN2009ku, which had an ejecta velocity of ~2000 kms^-1 at 18 days after maximum brightness is spectroscopically most similar to SN2008ha, which also had extremely low-velocity ejecta. However, SN2008ha had an exceedingly low luminosity, peaking at M_V = -14.2 mag, ~4 mag fainter than SN2009ku. The contrast of high luminosity and low ejecta velocity for SN2009ku is contrary to an emerging trend seen for the SN2002cx class. SN2009ku is a counter-example of a previously held belief that the class was more homogeneous than typical SNeIa, indicating that the class has a diverse progenitor population and/or complicated explosion physics. As the first example of a member of this class of objects from the new generation of transient surveys, SN2009ku is an indication of the potential for these surveys to find rare and interesting objects.Comment: 7 pages, 3 figure

Unique intrahepatic transcriptomics profiles discriminate the clinical phases of a chronic HBV infection

Chronic hepatitis B is a highly heterogeneous liver disease characterized by phases with fluctuations in viral replication and progressive liver damage in some, but not all infected individuals. Despite four decades of research, insight into host determinants underlying these distinct clinical phases-immunotolerant, immune active, inactive carrier, and HBeAg-negative hepatitis±remains elusive. We performed an in-depth transcriptome analysis of archived FFPE liver biopsies of each clinical phase to address host determinants associated with the natural history. Therefore, we determined, for the first time, intrahepatic global expression profiles of well-characterized chronic HBV patients at different clinical phases. Our data, obtained by microarray, demonstrate that B cells and NK/cytotoxicrelated genes in the liver, including CD19, TNFRSF13C, GZMH, and KIR2DS3, were differentially expressed across the clinical HBV phases, which was confirmed by modular analysis and also Nanostring arrays in an independent cohort. Compared to the immunotolerant phase, 92 genes were differentially expressed in the liver during the immune active phase, 46 in the inactive carrier phase, and 71 in the HBeAg-negative phase. Furthermore, our study also revealed distinctive transcription of genes associated with cell cycle activity, NF-κB signaling, cytotoxic function and mitochondrial respiration between clinical phases. Our data define for the first time using microarray unique transcriptomes in the HBV-infected liver during consecutive clinical phases. We demonstrate that fluctuations of viral loads and liver damage coincide with fluctuations in the liver transcriptome and point to functionalimmune and non-immune-components contributing to the clinical phenotype in patients

The Structure and Stellar Content of the Outer Disks of Galaxies: A New View from the Pan-STARRS1 Medium Deep Survey

We present the results of an analysis of Pan-STARRS1 Medium Deep Survey multi-band (grizy) images of a sample of 698 low-redshift disk galaxies that span broad ranges in stellar mass, star-formation rate, and bulge/disk ratio. We use population synthesis spectral energy distribution fitting techniques to explore the radial distribution of the light, color, surface mass density, mass/light ratio, and age of the stellar populations. We characterize the structure and stellar content of the galaxy disks out to radii of about twice Petrosian r 90, beyond which the halo light becomes significant. We measure normalized radial profiles for sub-samples of galaxies in three bins each of stellar mass and concentration. We also fit radial profiles to each galaxy. The majority of galaxies have down-bending radial surface brightness profiles in the bluer bands with a break radius at roughly r 90. However, they typically show single unbroken exponentials in the reddest bands and in the stellar surface mass density. We find that the mass/light ratio and stellar age radial profiles have a characteristic "U" shape. There is a good correlation between the amplitude of the down-bend in the surface brightness profile and the rate of the increase in the M/L ratio in the outer disk. As we move from late- to early-type galaxies, the amplitude of the down-bend and the radial gradient in M/L both decrease. Our results imply a combination of stellar radial migration and suppression of recent star formation can account for the stellar populations of the outer disk

Colorectal Cancer in Australian Young Adults

Purpose of Review: Although the overall incidence and mortality rates of colorectal cancer (CRC) have been decreasing in Australia over the last 20 years, there has been a significant increase in the incidence of early-onset CRC (EOCRC) without a clear explanation. In this review, we have outlined the epidemiology, suggested risk factors, clinicopathological and molecular features, survival and prognosis, and treatment approach for Australian young adults with CRC. Recent findings: There has been a shift in the epidemiology of bowel cancer incidence and mortality across different age groups, and there are clinicopathological and molecular feature differences between EOCRC and late onset CRC (LOCRC). EOCRC is more common in the distal colon and rectum. Young patients are diagnosed at more advanced stages of the disease with increased prevalence of aggressive pathologic features and tend to receive more aggressive chemotherapies. EOCRC patients present with a predominance of symptoms in the left side of the colon, and importantly, cases do not have clinically known risk factors. The microbiota may play a significant role in the CRC pathogenesis through an impact on host metabolism and through the transmission of metabolic and even CRC risk in non-Mendelian familial aggregation. Summary: The increase in the incidence and mortality rates of young adults with CRC has been significant. Thus, more collaborative research is needed to explain the reasons behind the increase in CRC incidence, and to identify young adults in the population at an increased risk of developing CRC at an early age.Reger R. Mikaeel, Timothy J. Price, Eric Smith, Paul A. Drew, Wendy Uylaki, Mehgan Horsnell, Joanne P. Youn

A Large Catalog of Accurate Distances to Molecular Clouds from PS1 Photometry

Distance measurements to molecular clouds are important but are often made separately for each cloud of interest, employing very different data and techniques. We present a large, homogeneous catalog of distances to molecular clouds, most of which are of unprecedented accuracy. We determine distances using optical photometry of stars along lines of sight toward these clouds, obtained from PanSTARRS-1. We simultaneously infer the reddenings and distances to these stars, tracking the full probability distribution function using a technique presented in Green et al. We fit these star-by-star measurements using a simple dust screen model to find the distance to each cloud. We thus estimate the distances to almost all of the clouds in the Magnani et al. catalog, as well as many other well-studied clouds, including Orion, Perseus, Taurus, Cepheus, Polaris, California, and Monoceros R2, avoiding only the inner Galaxy. Typical statistical uncertainties in the distances are 5%, though the systematic uncertainty stemming from the quality of our stellar models is about 10%. The resulting catalog is the largest catalog of accurate, directly measured distances to molecular clouds. Our distance estimates are generally consistent with available distance estimates from the literature, though in some cases the literature estimates are off by a factor of more than two