2,361 research outputs found

    Decision making processes in people with symptoms of acute myocardial infarction: qualitative study

    Get PDF
    Objective To identify, the themes that influence decision making processes used by patients with symptoms of acute myocardial infarction. Design Qualitative study using semistructured interviews. Setting Two district hospitals in North Yorkshire. Participants 22 patients admitted to hospital with confirmed second, third, or fourth acute myocardial infarction. Main outcome measure Patients' perceptions of their experience between the onset of symptoms and the decision to seek medical help. Results Six main themes that influence the decision making process were identified: appraisal of In symptoms, perceived risk, previous experience, psychological and emotional factors, use of the NHS, and context of the event. Conclusions Knowledge of symptoms may not be enough to promote prompt action in the event of an acute myocardial infarction. Cognitive and emotional processes, individual beliefs and values, and the influence of the context of the event should also be considered in individual interventions designed to reduce delay in the event of symptoms of acute myocardial infarction

    One- and three-dimensional pathways for proteins to reach specific DNA sites

    Full text link

    The Spitzer South Pole Telescope Deep Field Survey: Linking galaxies and halos at z=1.5

    Full text link
    We present an analysis of the clustering of high-redshift galaxies in the recently completed 94 deg2^2 Spitzer-SPT Deep Field survey. Applying flux and color cuts to the mid-infrared photometry efficiently selects galaxies at z1.5z\sim1.5 in the stellar mass range 10101011M10^{10}-10^{11}M_\odot, making this sample the largest used so far to study such a distant population. We measure the angular correlation function in different flux-limited samples at scales >6>6^{\prime \prime} (corresponding to physical distances >0.05>0.05 Mpc) and thereby map the one- and two-halo contributions to the clustering. We fit halo occupation distributions and determine how the central galaxy's stellar mass and satellite occupation depend on the halo mass. We measure a prominent peak in the stellar-to-halo mass ratio at a halo mass of log(Mhalo/M)=12.44±0.08\log(M_{\rm halo} / M_\odot) = 12.44\pm0.08, 4.5 times higher than the z=0z=0 value. This supports the idea of an evolving mass threshold above which star formation is quenched. We estimate the large-scale bias in the range bg=24b_g=2-4 and the satellite fraction to be fsat0.2f_\mathrm{sat}\sim0.2, showing a clear evolution compared to z=0z=0. We also find that, above a given stellar mass limit, the fraction of galaxies that are in similar mass pairs is higher at z=1.5z=1.5 than at z=0z=0. In addition, we measure that this fraction mildly increases with the stellar mass limit at z=1.5z=1.5, which is the opposite of the behavior seen at low-redshift.Comment: 32 pages, 22 figures. Published in MNRA

    Age-specific incidence of A/H1N1 2009 influenza infection in England from sequential antibody prevalence data using likelihood-based estimation.

    Get PDF
    Estimating the age-specific incidence of an emerging pathogen is essential for understanding its severity and transmission dynamics. This paper describes a statistical method that uses likelihoods to estimate incidence from sequential serological data. The method requires information on seroconversion intervals and allows integration of information on the temporal distribution of cases from clinical surveillance. Among a family of candidate incidences, a likelihood function is derived by reconstructing the change in seroprevalence from seroconversion following infection and comparing it with the observed sequence of positivity among the samples. This method is applied to derive the cumulative and weekly incidence of A/H1N1 pandemic influenza in England during the second wave using sera taken between September 2009 and February 2010 in four age groups (1-4, 5-14, 15-24, 25-44 years). The highest cumulative incidence was in 5-14 year olds (59%, 95% credible interval (CI): 52%, 68%) followed by 1-4 year olds (49%, 95% CI: 38%, 61%), rates 20 and 40 times higher respectively than estimated from clinical surveillance. The method provides a more accurate and continuous measure of incidence than achieved by comparing prevalence in samples grouped by time period

    Chandra and XMM-Newton Observations of RDCS1252.9-2927, A Massive Cluster at z=1.24

    Get PDF
    We present deep Chandra and XMM obervations of the galaxy cluster RDCS1252.9-2927, which was selected from the ROSAT Deep Cluster Survey (RDCS) and confirmed by extensive spectroscopy with the VLT at redshift z=1.237. With the Chandra data, the X-ray emission from the intra-cluster medium is well resolved and traced out to 500 kpc, thus allowing a measurement of the physical properties of the gas with unprecedented accuracy at this redshift. We detect a clear 6.7 keV Iron K line in the Chandra spectrum providing a redshift within 1% of the spectroscopic one. By augmenting our spectroscopic analysis with the XMM data (MOS detectors only), we significantly narrow down the 1 sigma error bar to 10% for the temperature and 30% for the metallicity, with best fit values kT = 6.0(+0.7,-0.5) keV, Z = 0.36(+0.12,-0.10) Z_sun. In the likely hypothesis of hydrostatic equilibrium, we measure a total mass of M_{500} = (1.9+-0.3)10^14 h_70^{-1}M_sun within R_{Delta=500} = 536 kpc. Overall, these observations imply that RDCS1252.9-2927 is the most X-ray luminous and likely the most massive bona-fide cluster discovered to date at z>1. When combined with current samples of distant clusters, these data lend further support to a mild evolution of the cluster scaling relations, as well the metallicity of the intra-cluster gas. Inspection of the cluster mass function in the current cosmological concordance model (h,Omega_m,Omega_Lambda)=(0.7,0.3,0.7) and sigma_8=0.7-0.8 shows that RDCS1252.9-2927 is an M* cluster at z=1.24, in keeping with number density expectations in the RDCS survey volume.Comment: 9 pages, 1 color figure (fig6.jpg). The Astronomical Journal in press (Jan 2004). Full resolution preprint available at http://www.eso.org/~prosati/RDCS1252

    The Galaxy Population of Cluster RXJ0848+4453 at z=1.27

    Get PDF
    We present a study of the galaxy population in the cluster RXJ0848+4453 at z=1.27, using deep HST NICMOS and WFPC2 images. We morphologically classify all galaxies to K_s=20.6 that are covered by the HST imaging, and determine photometric redshifts using deep ground based BRIzJK_s photometry. Of 22 likely cluster members with morphological classifications, eleven (50%) are classified as early-type galaxies, nine (41%) as spiral galaxies, and two (9%) as ``merger/peculiar''. At HST resolution the second brightest cluster galaxy is resolved into a spectacular merger between three red galaxies of similar luminosity, separated from each other by ~6 kpc, with an integrated magnitude K=17.6 (~3 L* at z=1.27). The two most luminous early-type galaxies also show evidence for recent or ongoing interactions. Mergers and interactions between galaxies are possible because RXJ0848+4453 is not yet relaxed. The fraction of early-type galaxies in our sample is similar to that in clusters at 0.5<z<1, and consistent with a gradual decrease of the number of early-type galaxies in clusters from z=0 to z=1.3. We find evidence that the color-magnitude relation of the early-type galaxies is less steep than in the nearby Coma cluster. This may indicate that the brightest early-type galaxies have young stellar populations at z=1.27, but is also consistent with predictions of single age ``monolithic'' models with a galactic wind. The scatter in the color-magnitude relation is ~0.04 in rest frame U-V, similar to that in clusters at 0<z<1. Taken together, these results show that luminous early-type galaxies exist in clusters at z~1.3, but that their number density may be smaller than in the local Universe. Additional observations are needed to determine whether the brightest early-type galaxies harbor young stellar populations.Comment: Accepted for publication in The Astrophysical Journal Letter

    Monte Carlo Comparisons to a Cryogenic Dark Matter Search Detector with low Transition-Edge-Sensor Transition Temperature

    Full text link
    We present results on phonon quasidiffusion and Transition Edge Sensor (TES) studies in a large, 3 inch diameter, 1 inch thick [100] high purity germanium crystal, cooled to 50 mK in the vacuum of a dilution refrigerator, and exposed with 59.5 keV gamma-rays from an Am-241 calibration source. We compare calibration data with results from a Monte Carlo which includes phonon quasidiffusion and the generation of phonons created by charge carriers as they are drifted across the detector by ionization readout channels. The phonon energy is then parsed into TES based phonon readout channels and input into a TES simulator

    Clustering of red galaxies around the z=1.53 quasar 3C270.1

    Full text link
    In the paradigm of hierarchical galaxy formation, luminous radio galaxies mark mass assembly peaks that should contain clusters of galaxies. Observations of the z=1.53 quasar 3C270.1 with the Spitzer Space Telescope at 3.6-24 micron and with the 6.5-m MMT in the z'- and Y-bands allow detection of potential cluster members via photometric redshifts. Compared with nearby control fields, there is an excess of 11 extremely red objects (EROs) at 1.33 < z_phot < 1.73, consistent with a proto-cluster around the quasar. The spectral energy distributions (SEDs) of 3/4 of the EROs are better fitted with passive elliptical galaxies than withdust-reddened starbursts, and of four sources well-detected on an archival HST snapshot image, all have undisturbed morphologies. However, one ERO, not covered by the HST image, is a double source with 0.8" separation on the z' image and a marginal (2sigma) 24 micron detection indicating a dust-enshrouded starburst. The EROs are more luminous than L* (H = -23.6 AB mag at z=1.5).Comment: 12 pages, 7 figures, accepted by Ap

    Leprosy Associated with Atypical Cutaneous Leishmaniasis in Nicaragua and Honduras

    Get PDF
    In Central America, few cases of leprosy have been reported, but the disease may be unrecognized. Diagnosis is based on clinical criteria and histology. Preliminary field work in Nicaragua and Honduras found patients, including many children, with skin lesions clinically suggestive of atypical cutaneous leishmaniasis or indeterminate leprosy. Histology could not distinguish these diseases although acid-fast organisms were visible in a few biopsies. Lesions healed after standard antimicrobial therapy for leprosy. In the present study, patients, family members, and other community members were skin-tested and provided nasal swabs and blood samples. Biopsies were taken from a subgroup of patients with clinical signs of infection. Two laboratories analyzed samples, using local in-house techniques. Mycobacterium leprae, Leishmania spp. and Leishmania infantum were detected using polymerase chain reactions. Mycobacterium leprae DNA was detected in blood samples and nasal swabs, including some cases where leprosy was not clinically suspected. Leishmania spp. were also detected in blood and nasal swabs. Most biopsies contained Leishmania DNA and coinfection of Leishmania spp. with M. leprae occurred in 33% of cases. Mycobacterium leprae DNA was also detected and sequenced from Nicaraguan and Honduran environmental samples. In conclusion, leprosy and leishmaniasis are present in both regions, and leprosy appears to be widespread. The nature of any relationship between these two pathogens and the epidemiology of these infections need to be elucidated

    A VLT spectroscopic survey of RX J0152.7-1357, a forming cluster of galaxies at z=0.837

    Full text link
    We present the results of an extensive spectroscopic survey of RX J0152.7-1357, one of the most massive distant clusters of galaxies known. Multi-object spectroscopy, carried out with FORS1 and FORS2 on the ESO Very Large Telescope (VLT), has allowed us to measure more than 200 redshifts in the cluster field and to confirm 102 galaxies as cluster members. The mean redshift of the cluster is z=0.837±0.001z=0.837 \pm 0.001 and we estimate the velocity dispersion of the overall cluster galaxy distribution to be $\sim 1600 \mathrm{km \ s^{-1}}.Thedistributionofclustermembersisclearlyirregular,withtwomainclumpsthatfollowtheXrayclusteremissionmappedbyChandra.Athirdclumpofgalaxiestotheeastofthecentralstructureandattheclusterredshifthasalsobeenidentified.Thetwomainclumpshavevelocitydispersionsof. The distribution of cluster members is clearly irregular, with two main clumps that follow the X-ray cluster emission mapped by Chandra. A third clump of galaxies to the east of the central structure and at the cluster redshift has also been identified. The two main clumps have velocity dispersions of \sim919and and \sim737 \mathrm{km s^{-1}}respectively,andthepeculiarvelocityofthetwoclumpssuggeststhattheywillmergeintoasinglemoremassivecluster.Asegregationinthestarformationactivityofthemembergalaxiesisobserved.Allstarforminggalaxiesarelocatedoutsidethehighdensitypeaks,whicharepopulatedonlybypassivegalaxies.Apopulationofredgalaxies(belongingtotheclusterredsequence)withclearpoststarburstspectralfeaturesand[OII]( respectively, and the peculiar velocity of the two clumps suggests that they will merge into a single more massive cluster. A segregation in the star formation activity of the member galaxies is observed. All star forming galaxies are located outside the high-density peaks, which are populated only by passive galaxies. A population of red galaxies (belonging to the cluster red sequence) with clear post-starburst spectral features and [OII] (\lambda$3727) emission lines is observed in the outskirts of the cluster. Two AGNs, which were previously confused with the diffuse X-ray emission from the intracluster medium in ROSAT and BeppoSAX observations, are found to be cluster members.Comment: 16 pages. 13 figures. Accepted for publication in Astronomy & Astrophysics. Tables 4 and 5 available in printed version. Corrected typos and missing reference
    corecore